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linux/fs/debugfs/file.c

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Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/*
* file.c - part of debugfs, a tiny little debug file system
*
* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2004 IBM Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* debugfs is for people to use instead of /proc or /sys.
fs: update location of filesystems documentation The filesystem documentation was moved from DocBook to Documentation/filesystems/. Update it at the sources. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-14 15:04:55 +00:00
* See Documentation/filesystems/ for more details.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*
*/
#include <linux/module.h>
#include <linux/fs.h>
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
#include <linux/seq_file.h>
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#include <linux/pagemap.h>
#include <linux/debugfs.h>
debugfs: bugfix: include <linux/io.h> in file.c The regs32 machinery uses readl. I forgot the mandatory include and the code was not compiling on all archs. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-21 09:01:40 +00:00
#include <linux/io.h>
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
#include <linux/slab.h>
debugfs: add get/set for atomic types debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 20:33:02 +00:00
#include <linux/atomic.h>
debugfs: add helper function to create device related seq_file This patch adds a helper function that simplifies adding a so-called single_open sequence file for device drivers. The calling device driver needs to provide a read function and a device pointer. The field struct seq_file::private will reference the device pointer upon call to the read function so the driver can obtain his data from it and do its task of providing the file content using seq_printf() calls and alike. Using this helper function also gets rid of the need to specify file operations per debugfs file. Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-09 10:31:58 +00:00
#include <linux/device.h>
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
#include <linux/srcu.h>
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
#include <asm/poll.h>
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
#include "internal.h"
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
struct poll_table_struct;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
static ssize_t default_read_file(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return 0;
}
static ssize_t default_write_file(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return count;
}
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
const struct file_operations debugfs_noop_file_operations = {
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
.read = default_read_file,
.write = default_write_file,
simple_open: automatically convert to simple_open() Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: <smpl> @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; </smpl> [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-05 21:25:11 +00:00
.open = simple_open,
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-15 16:52:59 +00:00
.llseek = noop_llseek,
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
};
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
/**
* debugfs_use_file_start - mark the beginning of file data access
* @dentry: the dentry object whose data is being accessed.
* @srcu_idx: a pointer to some memory to store a SRCU index in.
*
* Up to a matching call to debugfs_use_file_finish(), any
* successive call into the file removing functions debugfs_remove()
* and debugfs_remove_recursive() will block. Since associated private
* file data may only get freed after a successful return of any of
* the removal functions, you may safely access it after a successful
* call to debugfs_use_file_start() without worrying about
* lifetime issues.
*
* If -%EIO is returned, the file has already been removed and thus,
* it is not safe to access any of its data. If, on the other hand,
* it is allowed to access the file data, zero is returned.
*
* Regardless of the return code, any call to
* debugfs_use_file_start() must be followed by a matching call
* to debugfs_use_file_finish().
*/
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx)
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
__acquires(&debugfs_srcu)
{
*srcu_idx = srcu_read_lock(&debugfs_srcu);
barrier();
if (d_unlinked(dentry))
return -EIO;
return 0;
}
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
EXPORT_SYMBOL_GPL(debugfs_use_file_start);
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
/**
* debugfs_use_file_finish - mark the end of file data access
* @srcu_idx: the SRCU index "created" by a former call to
* debugfs_use_file_start().
*
* Allow any ongoing concurrent call into debugfs_remove() or
* debugfs_remove_recursive() blocked by a former call to
* debugfs_use_file_start() to proceed and return to its caller.
*/
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu)
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
{
srcu_read_unlock(&debugfs_srcu, srcu_idx);
}
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
EXPORT_SYMBOL_GPL(debugfs_use_file_finish);
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
#define F_DENTRY(filp) ((filp)->f_path.dentry)
static int open_proxy_open(struct inode *inode, struct file *filp)
{
const struct dentry *dentry = F_DENTRY(filp);
const struct file_operations *real_fops = NULL;
int srcu_idx, r;
r = debugfs_use_file_start(dentry, &srcu_idx);
if (r) {
r = -ENOENT;
goto out;
}
debugfs: introduce a public file_operations accessor This patch introduces an accessor which can be used by the users of debugfs (drivers, fs, ...) to get the original file_operations struct. It also removes the REAL_FOPS_DEREF macro in file.c and converts the code to use the public version. Previously, REAL_FOPS_DEREF was only available within the file.c of debugfs. But having a public getter available for debugfs users is important as some drivers (carl9170 and b43) use the pointer of the original file_operations in conjunction with container_of() within their debugfs implementations. Reviewed-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Cc: stable <stable@vger.kernel.org> # 4.7+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-17 19:43:01 +00:00
real_fops = debugfs_real_fops(filp);
debugfs: prevent access to possibly dead file_operations at file open Nothing prevents a dentry found by path lookup before a return of __debugfs_remove() to actually get opened after that return. Now, after the return of __debugfs_remove(), there are no guarantees whatsoever regarding the memory the corresponding inode's file_operations object had been kept in. Since __debugfs_remove() is seldomly invoked, usually from module exit handlers only, the race is hard to trigger and the impact is very low. A discussion of the problem outlined above as well as a suggested solution can be found in the (sub-)thread rooted at http://lkml.kernel.org/g/20130401203445.GA20862@ZenIV.linux.org.uk ("Yet another pipe related oops.") Basically, Greg KH suggests to introduce an intermediate fops and Al Viro points out that a pointer to the original ones may be stored in ->d_fsdata. Follow this line of reasoning: - Add SRCU as a reverse dependency of DEBUG_FS. - Introduce a srcu_struct object for the debugfs subsystem. - In debugfs_create_file(), store a pointer to the original file_operations object in ->d_fsdata. - Make debugfs_remove() and debugfs_remove_recursive() wait for a SRCU grace period after the dentry has been delete()'d and before they return to their callers. - Introduce an intermediate file_operations object named "debugfs_open_proxy_file_operations". It's ->open() functions checks, under the protection of a SRCU read lock, whether the dentry is still alive, i.e. has not been d_delete()'d and if so, tries to acquire a reference on the owning module. On success, it sets the file object's ->f_op to the original file_operations and forwards the ongoing open() call to the original ->open(). - For clarity, rename the former debugfs_file_operations to debugfs_noop_file_operations -- they are in no way canonical. The choice of SRCU over "normal" RCU is justified by the fact, that the former may also be used to protect ->i_private data from going away during the execution of a file's readers and writers which may (and do) sleep. Finally, introduce the fs/debugfs/internal.h header containing some declarations internal to the debugfs implementation. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:13 +00:00
real_fops = fops_get(real_fops);
if (!real_fops) {
/* Huh? Module did not clean up after itself at exit? */
WARN(1, "debugfs file owner did not clean up at exit: %pd",
dentry);
r = -ENXIO;
goto out;
}
replace_fops(filp, real_fops);
if (real_fops->open)
r = real_fops->open(inode, filp);
out:
debugfs_use_file_finish(srcu_idx);
return r;
}
const struct file_operations debugfs_open_proxy_file_operations = {
.open = open_proxy_open,
};
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
#define PROTO(args...) args
#define ARGS(args...) args
#define FULL_PROXY_FUNC(name, ret_type, filp, proto, args) \
static ret_type full_proxy_ ## name(proto) \
{ \
const struct dentry *dentry = F_DENTRY(filp); \
const struct file_operations *real_fops = \
debugfs: introduce a public file_operations accessor This patch introduces an accessor which can be used by the users of debugfs (drivers, fs, ...) to get the original file_operations struct. It also removes the REAL_FOPS_DEREF macro in file.c and converts the code to use the public version. Previously, REAL_FOPS_DEREF was only available within the file.c of debugfs. But having a public getter available for debugfs users is important as some drivers (carl9170 and b43) use the pointer of the original file_operations in conjunction with container_of() within their debugfs implementations. Reviewed-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Cc: stable <stable@vger.kernel.org> # 4.7+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-17 19:43:01 +00:00
debugfs_real_fops(filp); \
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
int srcu_idx; \
ret_type r; \
\
r = debugfs_use_file_start(dentry, &srcu_idx); \
if (likely(!r)) \
r = real_fops->name(args); \
debugfs_use_file_finish(srcu_idx); \
return r; \
}
FULL_PROXY_FUNC(llseek, loff_t, filp,
PROTO(struct file *filp, loff_t offset, int whence),
ARGS(filp, offset, whence));
FULL_PROXY_FUNC(read, ssize_t, filp,
PROTO(struct file *filp, char __user *buf, size_t size,
loff_t *ppos),
ARGS(filp, buf, size, ppos));
FULL_PROXY_FUNC(write, ssize_t, filp,
PROTO(struct file *filp, const char __user *buf, size_t size,
loff_t *ppos),
ARGS(filp, buf, size, ppos));
FULL_PROXY_FUNC(unlocked_ioctl, long, filp,
PROTO(struct file *filp, unsigned int cmd, unsigned long arg),
ARGS(filp, cmd, arg));
static unsigned int full_proxy_poll(struct file *filp,
struct poll_table_struct *wait)
{
const struct dentry *dentry = F_DENTRY(filp);
debugfs: introduce a public file_operations accessor This patch introduces an accessor which can be used by the users of debugfs (drivers, fs, ...) to get the original file_operations struct. It also removes the REAL_FOPS_DEREF macro in file.c and converts the code to use the public version. Previously, REAL_FOPS_DEREF was only available within the file.c of debugfs. But having a public getter available for debugfs users is important as some drivers (carl9170 and b43) use the pointer of the original file_operations in conjunction with container_of() within their debugfs implementations. Reviewed-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Cc: stable <stable@vger.kernel.org> # 4.7+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-17 19:43:01 +00:00
const struct file_operations *real_fops = debugfs_real_fops(filp);
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
int srcu_idx;
unsigned int r = 0;
if (debugfs_use_file_start(dentry, &srcu_idx)) {
debugfs_use_file_finish(srcu_idx);
return POLLHUP;
}
r = real_fops->poll(filp, wait);
debugfs_use_file_finish(srcu_idx);
return r;
}
static int full_proxy_release(struct inode *inode, struct file *filp)
{
const struct dentry *dentry = F_DENTRY(filp);
debugfs: introduce a public file_operations accessor This patch introduces an accessor which can be used by the users of debugfs (drivers, fs, ...) to get the original file_operations struct. It also removes the REAL_FOPS_DEREF macro in file.c and converts the code to use the public version. Previously, REAL_FOPS_DEREF was only available within the file.c of debugfs. But having a public getter available for debugfs users is important as some drivers (carl9170 and b43) use the pointer of the original file_operations in conjunction with container_of() within their debugfs implementations. Reviewed-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Cc: stable <stable@vger.kernel.org> # 4.7+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-17 19:43:01 +00:00
const struct file_operations *real_fops = debugfs_real_fops(filp);
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
const struct file_operations *proxy_fops = filp->f_op;
int r = 0;
/*
* We must not protect this against removal races here: the
* original releaser should be called unconditionally in order
* not to leak any resources. Releasers must not assume that
* ->i_private is still being meaningful here.
*/
if (real_fops->release)
r = real_fops->release(inode, filp);
replace_fops(filp, d_inode(dentry)->i_fop);
kfree((void *)proxy_fops);
fops_put(real_fops);
debugfs: propagate release() call result The result was being ignored and 0 was always returned. Return the actual result instead. Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-21 09:27:36 +00:00
return r;
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
}
static void __full_proxy_fops_init(struct file_operations *proxy_fops,
const struct file_operations *real_fops)
{
proxy_fops->release = full_proxy_release;
if (real_fops->llseek)
proxy_fops->llseek = full_proxy_llseek;
if (real_fops->read)
proxy_fops->read = full_proxy_read;
if (real_fops->write)
proxy_fops->write = full_proxy_write;
if (real_fops->poll)
proxy_fops->poll = full_proxy_poll;
if (real_fops->unlocked_ioctl)
proxy_fops->unlocked_ioctl = full_proxy_unlocked_ioctl;
}
static int full_proxy_open(struct inode *inode, struct file *filp)
{
const struct dentry *dentry = F_DENTRY(filp);
const struct file_operations *real_fops = NULL;
struct file_operations *proxy_fops = NULL;
int srcu_idx, r;
r = debugfs_use_file_start(dentry, &srcu_idx);
if (r) {
r = -ENOENT;
goto out;
}
debugfs: introduce a public file_operations accessor This patch introduces an accessor which can be used by the users of debugfs (drivers, fs, ...) to get the original file_operations struct. It also removes the REAL_FOPS_DEREF macro in file.c and converts the code to use the public version. Previously, REAL_FOPS_DEREF was only available within the file.c of debugfs. But having a public getter available for debugfs users is important as some drivers (carl9170 and b43) use the pointer of the original file_operations in conjunction with container_of() within their debugfs implementations. Reviewed-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Cc: stable <stable@vger.kernel.org> # 4.7+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-17 19:43:01 +00:00
real_fops = debugfs_real_fops(filp);
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
real_fops = fops_get(real_fops);
if (!real_fops) {
/* Huh? Module did not cleanup after itself at exit? */
WARN(1, "debugfs file owner did not clean up at exit: %pd",
dentry);
r = -ENXIO;
goto out;
}
proxy_fops = kzalloc(sizeof(*proxy_fops), GFP_KERNEL);
if (!proxy_fops) {
r = -ENOMEM;
goto free_proxy;
}
__full_proxy_fops_init(proxy_fops, real_fops);
replace_fops(filp, proxy_fops);
if (real_fops->open) {
r = real_fops->open(inode, filp);
debugfs: full_proxy_open(): free proxy on ->open() failure Debugfs' full_proxy_open(), the ->open() installed at all inodes created through debugfs_create_file(), - grabs a reference to the original struct file_operations instance passed to debugfs_create_file(), - dynamically allocates a proxy struct file_operations instance wrapping the original - and installs this at the file's ->f_op. Afterwards, it calls the original ->open() and passes its return value back to the VFS layer. Now, if that return value indicates failure, the VFS layer won't ever call ->release() and thus, neither the reference to the original file_operations nor the memory for the proxy file_operations will get released, i.e. both are leaked. Upon failure of the original fops' ->open(), undo the proxy installation. That is: - Set the struct file ->f_op to what it had been when full_proxy_open() was entered. - Drop the reference to the original file_operations. - Free the memory holding the proxy file_operations. Fixes: 49d200deaa68 ("debugfs: prevent access to removed files' private data") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-24 11:08:53 +00:00
if (r) {
replace_fops(filp, d_inode(dentry)->i_fop);
goto free_proxy;
} else if (filp->f_op != proxy_fops) {
debugfs: prevent access to removed files' private data Upon return of debugfs_remove()/debugfs_remove_recursive(), it might still be attempted to access associated private file data through previously opened struct file objects. If that data has been freed by the caller of debugfs_remove*() in the meanwhile, the reading/writing process would either encounter a fault or, if the memory address in question has been reassigned again, unrelated data structures could get overwritten. However, since debugfs files are seldomly removed, usually from module exit handlers only, the impact is very low. Currently, there are ~1000 call sites of debugfs_create_file() spread throughout the whole tree and touching all of those struct file_operations in order to make them file removal aware by means of checking the result of debugfs_use_file_start() from within their methods is unfeasible. Instead, wrap the struct file_operations by a lifetime managing proxy at file open: - In debugfs_create_file(), the original fops handed in has got stashed away in ->d_fsdata already. - In debugfs_create_file(), install a proxy file_operations factory, debugfs_full_proxy_file_operations, at ->i_fop. This proxy factory has got an ->open() method only. It carries out some lifetime checks and if successful, dynamically allocates and sets up a new struct file_operations proxy at ->f_op. Afterwards, it forwards to the ->open() of the original struct file_operations in ->d_fsdata, if any. The dynamically set up proxy at ->f_op has got a lifetime managing wrapper set for each of the methods defined in the original struct file_operations in ->d_fsdata. Its ->release()er frees the proxy again and forwards to the original ->release(), if any. In order not to mislead the VFS layer, it is strictly necessary to leave those fields blank in the proxy that have been NULL in the original struct file_operations also, i.e. aren't supported. This is why there is a need for dynamically allocated proxies. The choice made not to allocate a proxy instance for every dentry at file creation, but for every struct file object instantiated thereof is justified by the expected usage pattern of debugfs, namely that in general very few files get opened more than once at a time. The wrapper methods set in the struct file_operations implement lifetime managing by means of the SRCU protection facilities already in place for debugfs: They set up a SRCU read side critical section and check whether the dentry is still alive by means of debugfs_use_file_start(). If so, they forward the call to the original struct file_operation stored in ->d_fsdata, still under the protection of the SRCU read side critical section. This SRCU read side critical section prevents any pending debugfs_remove() and friends to return to their callers. Since a file's private data must only be freed after the return of debugfs_remove(), the ongoing proxied call is guarded against any file removal race. If, on the other hand, the initial call to debugfs_use_file_start() detects that the dentry is dead, the wrapper simply returns -EIO and does not forward the call. Note that the ->poll() wrapper is special in that its signature does not allow for the return of arbitrary -EXXX values and thus, POLLHUP is returned here. In order not to pollute debugfs with wrapper definitions that aren't ever needed, I chose not to define a wrapper for every struct file_operations method possible. Instead, a wrapper is defined only for the subset of methods which are actually set by any debugfs users. Currently, these are: ->llseek() ->read() ->write() ->unlocked_ioctl() ->poll() The ->release() wrapper is special in that it does not protect the original ->release() in any way from dead files in order not to leak resources. Thus, any ->release() handed to debugfs must implement file lifetime management manually, if needed. For only 33 out of a total of 434 releasers handed in to debugfs, it could not be verified immediately whether they access data structures that might have been freed upon a debugfs_remove() return in the meanwhile. Export debugfs_use_file_start() and debugfs_use_file_finish() in order to allow any ->release() to manually implement file lifetime management. For a set of common cases of struct file_operations implemented by the debugfs_core itself, future patches will incorporate file lifetime management directly within those in order to allow for their unproxied operation. Rename the original, non-proxying "debugfs_create_file()" to "debugfs_create_file_unsafe()" and keep it for future internal use by debugfs itself. Factor out code common to both into the new __debugfs_create_file(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:14 +00:00
/* No protection against file removal anymore. */
WARN(1, "debugfs file owner replaced proxy fops: %pd",
dentry);
goto free_proxy;
}
}
goto out;
free_proxy:
kfree(proxy_fops);
fops_put(real_fops);
out:
debugfs_use_file_finish(srcu_idx);
return r;
}
const struct file_operations debugfs_full_proxy_file_operations = {
.open = full_proxy_open,
};
debugfs: add support for self-protecting attribute file fops In order to protect them against file removal issues, debugfs_create_file() creates a lifetime managing proxy around each struct file_operations handed in. In cases where this struct file_operations is able to manage file lifetime by itself already, the proxy created by debugfs is a waste of resources. The most common class of struct file_operations given to debugfs are those defined by means of the DEFINE_SIMPLE_ATTRIBUTE() macro. Introduce a DEFINE_DEBUGFS_ATTRIBUTE() macro to allow any struct file_operations of this class to be easily made file lifetime aware and thus, to be operated unproxied. Specifically, introduce debugfs_attr_read() and debugfs_attr_write() which wrap simple_attr_read() and simple_attr_write() under the protection of a debugfs_use_file_start()/debugfs_use_file_finish() pair. Make DEFINE_DEBUGFS_ATTRIBUTE() set the defined struct file_operations' ->read() and ->write() members to these wrappers. Export debugfs_create_file_unsafe() in order to allow debugfs users to create their files in non-proxying operation mode. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:15 +00:00
ssize_t debugfs_attr_read(struct file *file, char __user *buf,
size_t len, loff_t *ppos)
{
ssize_t ret;
int srcu_idx;
ret = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
if (likely(!ret))
ret = simple_attr_read(file, buf, len, ppos);
debugfs_use_file_finish(srcu_idx);
return ret;
}
EXPORT_SYMBOL_GPL(debugfs_attr_read);
ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
size_t len, loff_t *ppos)
{
ssize_t ret;
int srcu_idx;
ret = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
if (likely(!ret))
ret = simple_attr_write(file, buf, len, ppos);
debugfs_use_file_finish(srcu_idx);
return ret;
}
EXPORT_SYMBOL_GPL(debugfs_attr_write);
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
static struct dentry *debugfs_create_mode_unsafe(const char *name, umode_t mode,
struct dentry *parent, void *value,
const struct file_operations *fops,
const struct file_operations *fops_ro,
const struct file_operations *fops_wo)
{
/* if there are no write bits set, make read only */
if (!(mode & S_IWUGO))
return debugfs_create_file_unsafe(name, mode, parent, value,
fops_ro);
/* if there are no read bits set, make write only */
if (!(mode & S_IRUGO))
return debugfs_create_file_unsafe(name, mode, parent, value,
fops_wo);
return debugfs_create_file_unsafe(name, mode, parent, value, fops);
}
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u8_set(void *data, u64 val)
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
{
*(u8 *)data = val;
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
return 0;
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
}
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u8_get(void *data, u64 *val)
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
{
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
*val = *(u8 *)data;
return 0;
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/**
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* directory dentry if set. If this parameter is %NULL, then the
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*
* This function creates a file in debugfs with the given name that
* contains the value of the variable @value. If the @mode variable is so
* set, it can be read from, and written to.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* you are responsible here.) If an error occurs, %NULL will be returned.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* returned. It is not wise to check for this value, but rather, check for
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* code.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_u8(const char *name, umode_t mode,
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
struct dentry *parent, u8 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u8,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_u8_ro, &fops_u8_wo);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_u8);
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u16_set(void *data, u64 val)
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
{
*(u16 *)data = val;
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
return 0;
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
}
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u16_get(void *data, u64 *val)
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
{
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
*val = *(u16 *)data;
return 0;
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n");
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/**
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* directory dentry if set. If this parameter is %NULL, then the
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*
* This function creates a file in debugfs with the given name that
* contains the value of the variable @value. If the @mode variable is so
* set, it can be read from, and written to.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* you are responsible here.) If an error occurs, %NULL will be returned.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* returned. It is not wise to check for this value, but rather, check for
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* code.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_u16(const char *name, umode_t mode,
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
struct dentry *parent, u16 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u16,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_u16_ro, &fops_u16_wo);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_u16);
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u32_set(void *data, u64 val)
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
{
*(u32 *)data = val;
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
return 0;
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
}
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u32_get(void *data, u64 *val)
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
{
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
*val = *(u32 *)data;
return 0;
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
[PATCH] libfs: add simple attribute files Based on the discussion about spufs attributes, this is my suggestion for a more generic attribute file support that can be used by both debugfs and spufs. Simple attribute files behave similarly to sequential files from a kernel programmers perspective in that a standard set of file operations is provided and only an open operation needs to be written that registers file specific get() and set() functions. These operations are defined as void foo_set(void *data, u64 val); and u64 foo_get(void *data); where data is the inode->u.generic_ip pointer of the file and the operations just need to make send of that pointer. The infrastructure makes sure this works correctly with concurrent access and partial read calls. A macro named DEFINE_SIMPLE_ATTRIBUTE is provided to further simplify using the attributes. This patch already contains the changes for debugfs to use attributes for its internal file operations. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-18 12:40:59 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/**
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* directory dentry if set. If this parameter is %NULL, then the
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*
* This function creates a file in debugfs with the given name that
* contains the value of the variable @value. If the @mode variable is so
* set, it can be read from, and written to.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* you are responsible here.) If an error occurs, %NULL will be returned.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* returned. It is not wise to check for this value, but rather, check for
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* code.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_u32(const char *name, umode_t mode,
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
struct dentry *parent, u32 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u32,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_u32_ro, &fops_u32_wo);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_u32);
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u64_set(void *data, u64 val)
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
{
*(u64 *)data = val;
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
return 0;
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
}
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
static int debugfs_u64_get(void *data, u64 *val)
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
{
libfs: allow error return from simple attributes Sometimes simple attributes might need to return an error, e.g. for acquiring a mutex interruptibly. In fact we have that situation in spufs already which is the original user of the simple attributes. This patch merged the temporarily forked attributes in spufs back into the main ones and allows to return errors. [akpm@linux-foundation.org: build fix] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <stefano.brivio@polimi.it> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:20:26 +00:00
*val = *(u64 *)data;
return 0;
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
/**
* debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*
* This function creates a file in debugfs with the given name that
* contains the value of the variable @value. If the @mode variable is so
* set, it can be read from, and written to.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
* you are responsible here.) If an error occurs, %NULL will be returned.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
* returned. It is not wise to check for this value, but rather, check for
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_u64(const char *name, umode_t mode,
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
struct dentry *parent, u64 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u64,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_u64_ro, &fops_u64_wo);
debugfs: Add debugfs_create_u64() I went to use this the other day, only to find it didn't exist. It's a straight copy of the debugfs u32 code, then s/u32/u64/. A quick test shows it seems to be working. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-04-17 05:59:36 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_u64);
debugfs: Add debugfs_create_ulong() Add debugfs_create_ulong() for the users of type 'unsigned long'. These will be 32 bits long on a 32 bit machine and 64 bits long on a 64 bit machine. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18 17:13:19 +00:00
static int debugfs_ulong_set(void *data, u64 val)
{
*(unsigned long *)data = val;
return 0;
}
static int debugfs_ulong_get(void *data, u64 *val)
{
*val = *(unsigned long *)data;
return 0;
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong, debugfs_ulong_get, debugfs_ulong_set,
"%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_ro, debugfs_ulong_get, NULL, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_wo, NULL, debugfs_ulong_set, "%llu\n");
debugfs: Add debugfs_create_ulong() Add debugfs_create_ulong() for the users of type 'unsigned long'. These will be 32 bits long on a 32 bit machine and 64 bits long on a 64 bit machine. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18 17:13:19 +00:00
/**
* debugfs_create_ulong - create a debugfs file that is used to read and write
* an unsigned long value.
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*
* This function creates a file in debugfs with the given name that
* contains the value of the variable @value. If the @mode variable is so
* set, it can be read from, and written to.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
* you are responsible here.) If an error occurs, %NULL will be returned.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
* returned. It is not wise to check for this value, but rather, check for
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
struct dentry *parent, unsigned long *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value,
&fops_ulong, &fops_ulong_ro,
&fops_ulong_wo);
debugfs: Add debugfs_create_ulong() Add debugfs_create_ulong() for the users of type 'unsigned long'. These will be 32 bits long on a 32 bit machine and 64 bits long on a 64 bit machine. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-18 17:13:19 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_ulong);
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n");
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set,
"0x%04llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_wo, NULL, debugfs_u16_set, "0x%04llx\n");
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set,
"0x%08llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n");
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set,
"0x%016llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_ro, debugfs_u64_get, NULL, "0x%016llx\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_wo, NULL, debugfs_u64_set, "0x%016llx\n");
Add x64 support to debugfs Add debugfs_create_x64. This is needed by ACPI APEI EINJ parameters support. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-18 06:35:23 +00:00
docbook: fix filesystems content Fix filesystems docbook warnings. Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'name' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'mode' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'parent' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'value' Warning(linux-2.6.23-git8//include/linux/jbd.h:404): No description found for parameter 'h_lockdep_map' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 00:30:19 +00:00
/*
Add x64 support to debugfs Add debugfs_create_x64. This is needed by ACPI APEI EINJ parameters support. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-18 06:35:23 +00:00
* debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
*
docbook: fix filesystems content Fix filesystems docbook warnings. Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'name' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'mode' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'parent' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'value' Warning(linux-2.6.23-git8//include/linux/jbd.h:404): No description found for parameter 'h_lockdep_map' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 00:30:19 +00:00
* These functions are exactly the same as the above functions (but use a hex
* output for the decimal challenged). For details look at the above unsigned
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
* decimal functions.
*/
docbook: fix filesystems content Fix filesystems docbook warnings. Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'name' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'mode' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'parent' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'value' Warning(linux-2.6.23-git8//include/linux/jbd.h:404): No description found for parameter 'h_lockdep_map' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 00:30:19 +00:00
/**
* debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_x8(const char *name, umode_t mode,
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
struct dentry *parent, u8 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x8,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_x8_ro, &fops_x8_wo);
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_x8);
docbook: fix filesystems content Fix filesystems docbook warnings. Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'name' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'mode' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'parent' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'value' Warning(linux-2.6.23-git8//include/linux/jbd.h:404): No description found for parameter 'h_lockdep_map' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 00:30:19 +00:00
/**
* debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_x16(const char *name, umode_t mode,
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
struct dentry *parent, u16 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x16,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_x16_ro, &fops_x16_wo);
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_x16);
docbook: fix filesystems content Fix filesystems docbook warnings. Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'name' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'mode' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'parent' Warning(linux-2.6.23-git8//fs/debugfs/file.c:241): No description found for parameter 'value' Warning(linux-2.6.23-git8//include/linux/jbd.h:404): No description found for parameter 'h_lockdep_map' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 00:30:19 +00:00
/**
* debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_x32(const char *name, umode_t mode,
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
struct dentry *parent, u32 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x32,
debugfs: Consolidate file mode checks in debugfs_create_*() The code that creates debugfs file with different file ops based on the file mode is duplicated in each debugfs_create_*() API. Consolidate that code into debugfs_create_mode(), that takes three file ops structures so that we don't have to keep copy/pasting that logic. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:09 +00:00
&fops_x32_ro, &fops_x32_wo);
debugfs: helper for decimal challenged Allows debugfs helper functions to have a hex output, rather than just decimal Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-08-02 22:23:50 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_x32);
Add x64 support to debugfs Add debugfs_create_x64. This is needed by ACPI APEI EINJ parameters support. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-18 06:35:23 +00:00
/**
* debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_x64(const char *name, umode_t mode,
Add x64 support to debugfs Add debugfs_create_x64. This is needed by ACPI APEI EINJ parameters support. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-18 06:35:23 +00:00
struct dentry *parent, u64 *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x64,
debugfs: Add read-only/write-only x64 file ops There aren't any read-only or write-only x64 file ops, but there is a caller of debugfs_create_x64() that calls it with mode equal to S_IRUGO. This leads to the possibility of userspace modifying the file, so let's use the newly created debugfs_create_mode() helper here to fix this. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:10 +00:00
&fops_x64_ro, &fops_x64_wo);
Add x64 support to debugfs Add debugfs_create_x64. This is needed by ACPI APEI EINJ parameters support. Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-18 06:35:23 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_x64);
debugfs: add helpers for exporting a size_t simple value In the same spirit as debugfs_create_*(), introduce helpers for exporting size_t values over debugfs. The only trick done is that the format verifier is kept at %llu instead of %zu; otherwise type warnings would pop up: format ‘%zu’ expects type ‘size_t’, but argument 2 has type ‘long long unsigned int’ There is no real way to fix this one--however, we can consider %llu and %zu to be compatible if we consider that we are using the same for validating in debugfs_create_{x,u}{8,16,32}(). Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-12-21 00:57:39 +00:00
static int debugfs_size_t_set(void *data, u64 val)
{
*(size_t *)data = val;
return 0;
}
static int debugfs_size_t_get(void *data, u64 *val)
{
*val = *(size_t *)data;
return 0;
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
"%llu\n"); /* %llu and %zu are more or less the same */
DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_ro, debugfs_size_t_get, NULL, "%llu\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_wo, NULL, debugfs_size_t_set, "%llu\n");
debugfs: add helpers for exporting a size_t simple value In the same spirit as debugfs_create_*(), introduce helpers for exporting size_t values over debugfs. The only trick done is that the format verifier is kept at %llu instead of %zu; otherwise type warnings would pop up: format ‘%zu’ expects type ‘size_t’, but argument 2 has type ‘long long unsigned int’ There is no real way to fix this one--however, we can consider %llu and %zu to be compatible if we consider that we are using the same for validating in debugfs_create_{x,u}{8,16,32}(). Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-12-21 00:57:39 +00:00
/**
* debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
debugfs: add helpers for exporting a size_t simple value In the same spirit as debugfs_create_*(), introduce helpers for exporting size_t values over debugfs. The only trick done is that the format verifier is kept at %llu instead of %zu; otherwise type warnings would pop up: format ‘%zu’ expects type ‘size_t’, but argument 2 has type ‘long long unsigned int’ There is no real way to fix this one--however, we can consider %llu and %zu to be compatible if we consider that we are using the same for validating in debugfs_create_{x,u}{8,16,32}(). Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-12-21 00:57:39 +00:00
struct dentry *parent, size_t *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value,
&fops_size_t, &fops_size_t_ro,
&fops_size_t_wo);
debugfs: add helpers for exporting a size_t simple value In the same spirit as debugfs_create_*(), introduce helpers for exporting size_t values over debugfs. The only trick done is that the format verifier is kept at %llu instead of %zu; otherwise type warnings would pop up: format ‘%zu’ expects type ‘size_t’, but argument 2 has type ‘long long unsigned int’ There is no real way to fix this one--however, we can consider %llu and %zu to be compatible if we consider that we are using the same for validating in debugfs_create_{x,u}{8,16,32}(). Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-12-21 00:57:39 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_size_t);
debugfs: add get/set for atomic types debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 20:33:02 +00:00
static int debugfs_atomic_t_set(void *data, u64 val)
{
atomic_set((atomic_t *)data, val);
return 0;
}
static int debugfs_atomic_t_get(void *data, u64 *val)
{
*val = atomic_read((atomic_t *)data);
return 0;
}
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
debugfs: add get/set for atomic types debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 20:33:02 +00:00
debugfs_atomic_t_set, "%lld\n");
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t_ro, debugfs_atomic_t_get, NULL,
"%lld\n");
DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set,
"%lld\n");
debugfs: add get/set for atomic types debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 20:33:02 +00:00
/**
* debugfs_create_atomic_t - create a debugfs file that is used to read and
* write an atomic_t value
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*/
struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
struct dentry *parent, atomic_t *value)
{
debugfs: unproxify integer attribute files Currently, the struct file_operations associated with the integer attribute style files created through the debugfs_create_*() helpers are not file lifetime aware as they are defined by means of DEFINE_SIMPLE_ATTRIBUTE(). Thus, a lifetime managing proxy is created around the original fops each time such a file is opened which is an unnecessary waste of resources. Migrate all usages of DEFINE_SIMPLE_ATTRIBUTE() within debugfs itself to DEFINE_DEBUGFS_ATTRIBUTE() in order to implement file lifetime managing within the struct file_operations thus defined. Introduce the debugfs_create_mode_unsafe() helper, analogous to debugfs_create_mode(), but distinct in that it creates the files in non-proxying operation mode through debugfs_create_file_unsafe(). Feed all struct file_operations migrated to DEFINE_DEBUGFS_ATTRIBUTE() into debugfs_create_mode_unsafe() instead of former debugfs_create_mode(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:17 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value,
&fops_atomic_t, &fops_atomic_t_ro,
&fops_atomic_t_wo);
debugfs: add get/set for atomic types debugfs currently lack the ability to create attributes that set/get atomic_t values. This patch adds support for this through a new debugfs_create_atomic_t() function. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 20:33:02 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_atomic_t);
debugfs: add helpers for exporting a size_t simple value In the same spirit as debugfs_create_*(), introduce helpers for exporting size_t values over debugfs. The only trick done is that the format verifier is kept at %llu instead of %zu; otherwise type warnings would pop up: format ‘%zu’ expects type ‘size_t’, but argument 2 has type ‘long long unsigned int’ There is no real way to fix this one--however, we can consider %llu and %zu to be compatible if we consider that we are using the same for validating in debugfs_create_{x,u}{8,16,32}(). Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-12-21 00:57:39 +00:00
debugfs: Export bool read/write functions The file read/write functions for bools have no special dependencies on debugfs internals and are sufficiently non-trivial to be worth exporting so clients can re-use the implementation. Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-23 13:32:54 +00:00
ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
{
char buf[3];
debugfs: unproxify files created through debugfs_create_bool() Currently, the struct file_operations fops_bool associated with files created through the debugfs_create_bool() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_bool each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make debugfs_read_file_bool() and debugfs_write_file_bool() safe against file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_bool() create its files in non-proxying operation mode through debugfs_create_mode_unsafe(). Finally, purge debugfs_create_mode() as debugfs_create_bool() had been its last user. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:18 +00:00
bool val;
int r, srcu_idx;
r = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
if (likely(!r))
val = *(bool *)file->private_data;
debugfs_use_file_finish(srcu_idx);
if (r)
return r;
fs: debugfs: remove trailing whitespace fixes checkpatch.pl trailing whitespace errors Signed-off-by: Rahul Bedarkar <rahulbedarkar89@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-06 17:42:04 +00:00
debugfs: unproxify files created through debugfs_create_bool() Currently, the struct file_operations fops_bool associated with files created through the debugfs_create_bool() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_bool each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make debugfs_read_file_bool() and debugfs_write_file_bool() safe against file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_bool() create its files in non-proxying operation mode through debugfs_create_mode_unsafe(). Finally, purge debugfs_create_mode() as debugfs_create_bool() had been its last user. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:18 +00:00
if (val)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
buf[0] = 'Y';
else
buf[0] = 'N';
buf[1] = '\n';
buf[2] = 0x00;
return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
}
debugfs: Export bool read/write functions The file read/write functions for bools have no special dependencies on debugfs internals and are sufficiently non-trivial to be worth exporting so clients can re-use the implementation. Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-23 13:32:54 +00:00
EXPORT_SYMBOL_GPL(debugfs_read_file_bool);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
debugfs: Export bool read/write functions The file read/write functions for bools have no special dependencies on debugfs internals and are sufficiently non-trivial to be worth exporting so clients can re-use the implementation. Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-23 13:32:54 +00:00
ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
{
char buf[32];
debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning Enabling DEBUG_STRICT_USER_COPY_CHECKS causes the following warning: In file included from arch/x86/include/asm/uaccess.h:573, from include/linux/uaccess.h:5, from include/linux/highmem.h:7, from include/linux/pagemap.h:10, from fs/debugfs/file.c:18: In function 'copy_from_user', inlined from 'write_file_bool' at fs/debugfs/file.c:435: arch/x86/include/asm/uaccess_64.h:65: warning: call to 'copy_from_user_overflow' declared with attribute warning: copy_from_user() buffer size is not provably correct presumably due to buf_size being signed causing GCC to fail to see that buf_size can't become negative. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-12 23:50:07 +00:00
size_t buf_size;
debugfs: move to new strtobool No functional changes requires that we eat errors from strtobool. If people want to not do this, then it should be fixed at a later date. V2: Simplification suggested by Rusty Russell removes the need for additional variable ret. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-19 11:43:46 +00:00
bool bv;
debugfs: unproxify files created through debugfs_create_bool() Currently, the struct file_operations fops_bool associated with files created through the debugfs_create_bool() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_bool each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make debugfs_read_file_bool() and debugfs_write_file_bool() safe against file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_bool() create its files in non-proxying operation mode through debugfs_create_mode_unsafe(). Finally, purge debugfs_create_mode() as debugfs_create_bool() had been its last user. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:18 +00:00
int r, srcu_idx;
debugfs: Pass bool pointer to debugfs_create_bool() Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument, when all it needs is a boolean pointer. It would be better to update this API to make it accept 'bool *' instead, as that will make it more consistent and often more convenient. Over that bool takes just a byte. That required updates to all user sites as well, in the same commit updating the API. regmap core was also using debugfs_{read|write}_file_bool(), directly and variable types were updated for that to be bool as well. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-26 22:04:07 +00:00
bool *val = file->private_data;
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
buf_size = min(count, (sizeof(buf)-1));
if (copy_from_user(buf, user_buf, buf_size))
return -EFAULT;
debugfs: write_file_bool() - ensure strtobool() operates on valid data In case, userland writes an empty string to a bool debugfs file, buf[] will still be uninitialized when being passed to strtobool() making the outcome of that function purely random. Fix this by always zero-terminating the buffer. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-31 21:24:29 +00:00
buf[buf_size] = '\0';
debugfs: unproxify files created through debugfs_create_bool() Currently, the struct file_operations fops_bool associated with files created through the debugfs_create_bool() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_bool each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make debugfs_read_file_bool() and debugfs_write_file_bool() safe against file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_bool() create its files in non-proxying operation mode through debugfs_create_mode_unsafe(). Finally, purge debugfs_create_mode() as debugfs_create_bool() had been its last user. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:18 +00:00
if (strtobool(buf, &bv) == 0) {
r = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
if (likely(!r))
*val = bv;
debugfs_use_file_finish(srcu_idx);
if (r)
return r;
}
debugfs: move to new strtobool No functional changes requires that we eat errors from strtobool. If people want to not do this, then it should be fixed at a later date. V2: Simplification suggested by Rusty Russell removes the need for additional variable ret. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-19 11:43:46 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
return count;
}
debugfs: Export bool read/write functions The file read/write functions for bools have no special dependencies on debugfs internals and are sufficiently non-trivial to be worth exporting so clients can re-use the implementation. Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-23 13:32:54 +00:00
EXPORT_SYMBOL_GPL(debugfs_write_file_bool);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
[PATCH] Make most file operations structs in fs/ const This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:56:42 +00:00
static const struct file_operations fops_bool = {
debugfs: Export bool read/write functions The file read/write functions for bools have no special dependencies on debugfs internals and are sufficiently non-trivial to be worth exporting so clients can re-use the implementation. Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-23 13:32:54 +00:00
.read = debugfs_read_file_bool,
.write = debugfs_write_file_bool,
simple_open: automatically convert to simple_open() Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: <smpl> @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; </smpl> [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-05 21:25:11 +00:00
.open = simple_open,
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-15 16:52:59 +00:00
.llseek = default_llseek,
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
};
debugfs: Add read-only/write-only bool file ops There aren't any read-only or write-only bool file ops, but there is a caller of debugfs_create_bool() that calls it with mode equal to 0400. This leads to the possibility of userspace modifying the file, so let's use the newly created debugfs_create_mode() helper here to fix this. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:12 +00:00
static const struct file_operations fops_bool_ro = {
.read = debugfs_read_file_bool,
.open = simple_open,
.llseek = default_llseek,
};
static const struct file_operations fops_bool_wo = {
.write = debugfs_write_file_bool,
.open = simple_open,
.llseek = default_llseek,
};
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/**
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* directory dentry if set. If this parameter is %NULL, then the
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* file will be created in the root of the debugfs filesystem.
* @value: a pointer to the variable that the file should read to and write
* from.
*
* This function creates a file in debugfs with the given name that
* contains the value of the variable @value. If the @mode variable is so
* set, it can be read from, and written to.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* you are responsible here.) If an error occurs, %NULL will be returned.
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* returned. It is not wise to check for this value, but rather, check for
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
* code.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_bool(const char *name, umode_t mode,
debugfs: Pass bool pointer to debugfs_create_bool() Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument, when all it needs is a boolean pointer. It would be better to update this API to make it accept 'bool *' instead, as that will make it more consistent and often more convenient. Over that bool takes just a byte. That required updates to all user sites as well, in the same commit updating the API. regmap core was also using debugfs_{read|write}_file_bool(), directly and variable types were updated for that to be bool as well. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-26 22:04:07 +00:00
struct dentry *parent, bool *value)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
{
debugfs: unproxify files created through debugfs_create_bool() Currently, the struct file_operations fops_bool associated with files created through the debugfs_create_bool() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_bool each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make debugfs_read_file_bool() and debugfs_write_file_bool() safe against file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_bool() create its files in non-proxying operation mode through debugfs_create_mode_unsafe(). Finally, purge debugfs_create_mode() as debugfs_create_bool() had been its last user. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:18 +00:00
return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_bool,
debugfs: Add read-only/write-only bool file ops There aren't any read-only or write-only bool file ops, but there is a caller of debugfs_create_bool() that calls it with mode equal to 0400. This leads to the possibility of userspace modifying the file, so let's use the newly created debugfs_create_mode() helper here to fix this. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-13 01:09:12 +00:00
&fops_bool_ro, &fops_bool_wo);
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_bool);
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
static ssize_t read_file_blob(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct debugfs_blob_wrapper *blob = file->private_data;
debugfs: unproxify files created through debugfs_create_blob() Currently, the struct file_operations fops_blob associated with files created through the debugfs_create_blob() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_blob each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make read_file_blob() safe gainst file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_blob() create its files in non-proxying operation mode by means of debugfs_create_file_unsafe(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:19 +00:00
ssize_t r;
int srcu_idx;
r = debugfs_use_file_start(F_DENTRY(file), &srcu_idx);
if (likely(!r))
r = simple_read_from_buffer(user_buf, count, ppos, blob->data,
blob->size);
debugfs_use_file_finish(srcu_idx);
return r;
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
}
[PATCH] mark struct file_operations const 6 Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 08:55:34 +00:00
static const struct file_operations fops_blob = {
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
.read = read_file_blob,
simple_open: automatically convert to simple_open() Many users of debugfs copy the implementation of default_open() when they want to support a custom read/write function op. This leads to a proliferation of the default_open() implementation across the entire tree. Now that the common implementation has been consolidated into libfs we can replace all the users of this function with simple_open(). This replacement was done with the following semantic patch: <smpl> @ open @ identifier open_f != simple_open; identifier i, f; @@ -int open_f(struct inode *i, struct file *f) -{ ( -if (i->i_private) -f->private_data = i->i_private; | -f->private_data = i->i_private; ) -return 0; -} @ has_open depends on open @ identifier fops; identifier open.open_f; @@ struct file_operations fops = { ... -.open = open_f, +.open = simple_open, ... }; </smpl> [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-05 21:25:11 +00:00
.open = simple_open,
llseek: automatically add .llseek fop All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-08-15 16:52:59 +00:00
.llseek = default_llseek,
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
};
/**
debugfs: fix docbook error Fix an error in debugfs_create_blob's docbook description It cannot actually be used to write a binary blob. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2009-05-25 16:15:27 +00:00
* debugfs_create_blob - create a debugfs file that is used to read a binary blob
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* directory dentry if set. If this parameter is %NULL, then the
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
* file will be created in the root of the debugfs filesystem.
* @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
* to the blob data and the size of the data.
*
* This function creates a file in debugfs with the given name that exports
* @blob->data as a binary blob. If the @mode variable is so set it can be
* read from. Writing is not supported.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* you are responsible here.) If an error occurs, %NULL will be returned.
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
*
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
* returned. It is not wise to check for this value, but rather, check for
Debugfs: kernel-doc fixes for debugfs Fix kernel-doc and typos/spellos in fs/debugfs/. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-20 15:16:42 +00:00
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
* code.
*/
switch debugfs to umode_t Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-24 08:33:43 +00:00
struct dentry *debugfs_create_blob(const char *name, umode_t mode,
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
struct dentry *parent,
struct debugfs_blob_wrapper *blob)
{
debugfs: unproxify files created through debugfs_create_blob() Currently, the struct file_operations fops_blob associated with files created through the debugfs_create_blob() helpers are not file lifetime aware. Thus, a lifetime managing proxy is created around fops_blob each time such a file is opened which is an unnecessary waste of resources. Implement file lifetime management for the fops_bool file_operations. Namely, make read_file_blob() safe gainst file removals by means of debugfs_use_file_start() and debugfs_use_file_finish(). Make debugfs_create_blob() create its files in non-proxying operation mode by means of debugfs_create_file_unsafe(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:19 +00:00
return debugfs_create_file_unsafe(name, mode, parent, blob, &fops_blob);
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data I wanted to export a binary blob via debugfs, and although it was pretty easy it seems like it'd be easier if there was a helper for it. It's a pity we need the wrapper struct but I can't see a cleaner way to do it. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-07 10:41:59 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_blob);
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
struct array_data {
void *array;
u32 elements;
};
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
static size_t u32_format_array(char *buf, size_t bufsize,
u32 *array, int array_size)
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
{
size_t ret = 0;
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
while (--array_size >= 0) {
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
size_t len;
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
char term = array_size ? ' ' : '\n';
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
len = snprintf(buf, bufsize, "%u%c", *array++, term);
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
ret += len;
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
buf += len;
bufsize -= len;
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
}
return ret;
}
debugfs: fix race in u32_array_read and allocate array at open u32_array_open() is racy when multiple threads read from a file with a seek position of zero, i.e. when two or more simultaneous reads are occurring after the non-seekable files are created. It is possible that file->private_data is double-freed because the threads races between kfree(file->private-data); and file->private_data = NULL; The fix is to only do format_array_alloc() when the file is opened and free it when it is closed. Note that because the file has always been non-seekable, you can't open it and read it multiple times anyway, so the data has always been generated just once. The difference is that now it is generated at open time rather than at the time of the first read, and that avoids the race. Reported-by: Dave Jones <davej@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Raghavendra <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 09:16:29 +00:00
static int u32_array_open(struct inode *inode, struct file *file)
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
{
struct array_data *data = inode->i_private;
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
int size, elements = data->elements;
char *buf;
/*
* Max size:
* - 10 digits + ' '/'\n' = 11 bytes per number
* - terminating NUL character
*/
size = elements*11;
buf = kmalloc(size+1, GFP_KERNEL);
if (!buf)
debugfs: fix race in u32_array_read and allocate array at open u32_array_open() is racy when multiple threads read from a file with a seek position of zero, i.e. when two or more simultaneous reads are occurring after the non-seekable files are created. It is possible that file->private_data is double-freed because the threads races between kfree(file->private-data); and file->private_data = NULL; The fix is to only do format_array_alloc() when the file is opened and free it when it is closed. Note that because the file has always been non-seekable, you can't open it and read it multiple times anyway, so the data has always been generated just once. The difference is that now it is generated at open time rather than at the time of the first read, and that avoids the race. Reported-by: Dave Jones <davej@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Raghavendra <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 09:16:29 +00:00
return -ENOMEM;
debugfs: fix u32_array race in format_array_alloc The format_array_alloc() function is fundamentally racy, in that it prints the array twice: once to figure out how much space to allocate for the buffer, and the second time to actually print out the data. If any of the array contents changes in between, the allocation size may be wrong, and the end result may be truncated in odd ways. Just don't do it. Allocate a maximum-sized array up-front, and just format the array contents once. The only user of the u32_array interfaces is the Xen spinlock statistics code, and it has 31 entries in the arrays, so the maximum size really isn't that big, and the end result is much simpler code without the bug. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 18:48:05 +00:00
buf[size] = 0;
file->private_data = buf;
u32_format_array(buf, size, data->array, data->elements);
debugfs: fix race in u32_array_read and allocate array at open u32_array_open() is racy when multiple threads read from a file with a seek position of zero, i.e. when two or more simultaneous reads are occurring after the non-seekable files are created. It is possible that file->private_data is double-freed because the threads races between kfree(file->private-data); and file->private_data = NULL; The fix is to only do format_array_alloc() when the file is opened and free it when it is closed. Note that because the file has always been non-seekable, you can't open it and read it multiple times anyway, so the data has always been generated just once. The difference is that now it is generated at open time rather than at the time of the first read, and that avoids the race. Reported-by: Dave Jones <davej@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Raghavendra <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 09:16:29 +00:00
return nonseekable_open(inode, file);
}
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
debugfs: fix race in u32_array_read and allocate array at open u32_array_open() is racy when multiple threads read from a file with a seek position of zero, i.e. when two or more simultaneous reads are occurring after the non-seekable files are created. It is possible that file->private_data is double-freed because the threads races between kfree(file->private-data); and file->private_data = NULL; The fix is to only do format_array_alloc() when the file is opened and free it when it is closed. Note that because the file has always been non-seekable, you can't open it and read it multiple times anyway, so the data has always been generated just once. The difference is that now it is generated at open time rather than at the time of the first read, and that avoids the race. Reported-by: Dave Jones <davej@redhat.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Raghavendra <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-21 09:16:29 +00:00
static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
size_t size = strlen(file->private_data);
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
return simple_read_from_buffer(buf, len, ppos,
file->private_data, size);
}
static int u32_array_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
return 0;
}
static const struct file_operations u32_array_fops = {
.owner = THIS_MODULE,
.open = u32_array_open,
.release = u32_array_release,
.read = u32_array_read,
.llseek = no_llseek,
};
/**
* debugfs_create_u32_array - create a debugfs file that is used to read u32
* array.
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have.
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @array: u32 array that provides data.
* @elements: total number of elements in the array.
*
* This function creates a file in debugfs with the given name that exports
* @array as data. If the @mode variable is so set it can be read from.
* Writing is not supported. Seek within the file is also not supported.
* Once array is created its size can not be changed.
*
* The function returns a pointer to dentry on success. If debugfs is not
* enabled in the kernel, the value -%ENODEV will be returned.
*/
struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, u32 elements)
{
struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
if (data == NULL)
return NULL;
data->array = array;
data->elements = elements;
debugfs: unproxify files created through debugfs_create_u32_array() The struct file_operations u32_array_fops associated with files created through debugfs_create_u32_array() has been lifetime aware already: everything needed for subsequent operation is copied to a ->f_private buffer at file opening time in u32_array_open(). Now, ->open() is always protected against file removal issues by the debugfs core. There is no need for the debugfs core to wrap the u32_array_fops with a file lifetime managing proxy. Make debugfs_create_u32_array() create its files in non-proxying operation mode by means of debugfs_create_file_unsafe(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-22 13:11:20 +00:00
return debugfs_create_file_unsafe(name, mode, parent, data,
&u32_array_fops);
debugfs: Add support to print u32 array in debugfs Move the code from Xen to debugfs to make the code common for other users as well. Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [v1: Fixed rebase issues] [v2: Fixed PPC compile issues] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-23 08:06:28 +00:00
}
EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
debugfs: add missing #ifdef HAS_IOMEM "debugfs: add tools to printk 32-bit registers" adds new functions which rely on IOMEM functionality which is not present on all architectures and therefore result in compile errors: fs/debugfs/file.c: In function 'debugfs_print_regs32': fs/debugfs/file.c:561:7: error: implicit declaration of function 'readl' [-Werror=implicit-function-declaration] Add an #ifdef CONFIG_HAS_IOMEM to fix this Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Alessandro Rubini <rubini@gnudd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-27 14:08:28 +00:00
#ifdef CONFIG_HAS_IOMEM
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
/*
* The regset32 stuff is used to print 32-bit registers using the
* seq_file utilities. We offer printing a register set in an already-opened
* sequential file or create a debugfs file that only prints a regset32.
*/
/**
* debugfs_print_regs32 - use seq_print to describe a set of registers
* @s: the seq_file structure being used to generate output
* @regs: an array if struct debugfs_reg32 structures
kernel-doc: fix new warnings in debugfs Fix new kernel-doc warnings: Warning(fs/debugfs/file.c:556): No description found for parameter 'nregs' Warning(fs/debugfs/file.c:556): Excess function parameter 'mregs' description in 'debugfs_print_regs32' Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-21 19:02:42 +00:00
* @nregs: the length of the above array
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
* @base: the base address to be used in reading the registers
* @prefix: a string to be prefixed to every output line
*
* This function outputs a text block describing the current values of
* some 32-bit hardware registers. It is meant to be used within debugfs
* files based on seq_file that need to show registers, intermixed with other
* information. The prefix argument may be used to specify a leading string,
* because some peripherals have several blocks of identical registers,
* for example configuration of dma channels
*/
debugfs: Have debugfs_print_regs32() return void The seq_printf() will soon just return void, and seq_has_overflowed() should be used instead to see if the seq can no longer accept input. As the return value of debugfs_print_regs32() has no users and the seq_file descriptor should be checked with seq_has_overflowed() instead of return values of functions, it is better to just have debugfs_print_regs32() also return void. Link: http://lkml.kernel.org/p/2634b19eb1c04a9d31148c1fe6f1f3819be95349.1412031505.git.joe@perches.com Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Joe Perches <joe@perches.com> [ original change only updated seq_printf() return, added return of void to debugfs_print_regs32() as well ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-09-29 23:08:26 +00:00
void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
int nregs, void __iomem *base, char *prefix)
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
{
debugfs: Have debugfs_print_regs32() return void The seq_printf() will soon just return void, and seq_has_overflowed() should be used instead to see if the seq can no longer accept input. As the return value of debugfs_print_regs32() has no users and the seq_file descriptor should be checked with seq_has_overflowed() instead of return values of functions, it is better to just have debugfs_print_regs32() also return void. Link: http://lkml.kernel.org/p/2634b19eb1c04a9d31148c1fe6f1f3819be95349.1412031505.git.joe@perches.com Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Joe Perches <joe@perches.com> [ original change only updated seq_printf() return, added return of void to debugfs_print_regs32() as well ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-09-29 23:08:26 +00:00
int i;
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
for (i = 0; i < nregs; i++, regs++) {
if (prefix)
debugfs: Have debugfs_print_regs32() return void The seq_printf() will soon just return void, and seq_has_overflowed() should be used instead to see if the seq can no longer accept input. As the return value of debugfs_print_regs32() has no users and the seq_file descriptor should be checked with seq_has_overflowed() instead of return values of functions, it is better to just have debugfs_print_regs32() also return void. Link: http://lkml.kernel.org/p/2634b19eb1c04a9d31148c1fe6f1f3819be95349.1412031505.git.joe@perches.com Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Joe Perches <joe@perches.com> [ original change only updated seq_printf() return, added return of void to debugfs_print_regs32() as well ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-09-29 23:08:26 +00:00
seq_printf(s, "%s", prefix);
seq_printf(s, "%s = 0x%08x\n", regs->name,
readl(base + regs->offset));
if (seq_has_overflowed(s))
break;
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
}
}
EXPORT_SYMBOL_GPL(debugfs_print_regs32);
static int debugfs_show_regset32(struct seq_file *s, void *data)
{
struct debugfs_regset32 *regset = s->private;
debugfs_print_regs32(s, regset->regs, regset->nregs, regset->base, "");
return 0;
}
static int debugfs_open_regset32(struct inode *inode, struct file *file)
{
return single_open(file, debugfs_show_regset32, inode->i_private);
}
static const struct file_operations fops_regset32 = {
.open = debugfs_open_regset32,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
/**
* debugfs_create_regset32 - create a debugfs file that returns register values
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @regset: a pointer to a struct debugfs_regset32, which contains a pointer
* to an array of register definitions, the array size and the base
* address where the register bank is to be found.
*
* This function creates a file in debugfs with the given name that reports
* the names and values of a set of 32-bit registers. If the @mode variable
* is so set it can be read from. Writing is not supported.
*
* This function will return a pointer to a dentry if it succeeds. This
* pointer must be passed to the debugfs_remove() function when the file is
* to be removed (no automatic cleanup happens if your module is unloaded,
* you are responsible here.) If an error occurs, %NULL will be returned.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
* returned. It is not wise to check for this value, but rather, check for
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
debugfs-related mode_t whack-a-mole all of those should be umode_t... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20 10:00:24 +00:00
struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
debugfs: add tools to printk 32-bit registers Some debugfs file I deal with are mostly blocks of registers, i.e. lines of the form "<name> = 0x<value>". Some files are only registers, some include registers blocks among other material. This patch introduces data structures and functions to deal with both cases. I expect more users of this over time. Signed-off-by: Alessandro Rubini <rubini@gnudd.com> Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com> Cc: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-18 13:50:21 +00:00
struct dentry *parent,
struct debugfs_regset32 *regset)
{
return debugfs_create_file(name, mode, parent, regset, &fops_regset32);
}
EXPORT_SYMBOL_GPL(debugfs_create_regset32);
debugfs: add missing #ifdef HAS_IOMEM "debugfs: add tools to printk 32-bit registers" adds new functions which rely on IOMEM functionality which is not present on all architectures and therefore result in compile errors: fs/debugfs/file.c: In function 'debugfs_print_regs32': fs/debugfs/file.c:561:7: error: implicit declaration of function 'readl' [-Werror=implicit-function-declaration] Add an #ifdef CONFIG_HAS_IOMEM to fix this Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Alessandro Rubini <rubini@gnudd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-12-27 14:08:28 +00:00
#endif /* CONFIG_HAS_IOMEM */
debugfs: add helper function to create device related seq_file This patch adds a helper function that simplifies adding a so-called single_open sequence file for device drivers. The calling device driver needs to provide a read function and a device pointer. The field struct seq_file::private will reference the device pointer upon call to the read function so the driver can obtain his data from it and do its task of providing the file content using seq_printf() calls and alike. Using this helper function also gets rid of the need to specify file operations per debugfs file. Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-09 10:31:58 +00:00
struct debugfs_devm_entry {
int (*read)(struct seq_file *seq, void *data);
struct device *dev;
};
static int debugfs_devm_entry_open(struct inode *inode, struct file *f)
{
struct debugfs_devm_entry *entry = inode->i_private;
return single_open(f, entry->read, entry->dev);
}
static const struct file_operations debugfs_devm_entry_ops = {
.owner = THIS_MODULE,
.open = debugfs_devm_entry_open,
.release = single_release,
.read = seq_read,
.llseek = seq_lseek
};
/**
* debugfs_create_devm_seqfile - create a debugfs file that is bound to device.
*
* @dev: device related to this debugfs file.
* @name: name of the debugfs file.
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @read_fn: function pointer called to print the seq_file content.
*/
struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
struct dentry *parent,
int (*read_fn)(struct seq_file *s,
void *data))
{
struct debugfs_devm_entry *entry;
if (IS_ERR(parent))
return ERR_PTR(-ENOENT);
entry = devm_kzalloc(dev, sizeof(*entry), GFP_KERNEL);
if (!entry)
return ERR_PTR(-ENOMEM);
entry->read = read_fn;
entry->dev = dev;
return debugfs_create_file(name, S_IRUGO, parent, entry,
&debugfs_devm_entry_ops);
}
EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile);
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