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linux/fs/sysfs/sysfs.h

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sysfs: move struct sysfs_dirent to private header struct sysfs_dirent is private to the fs/sysfs/ subtree. It is not even referenced as an opaque structure outside of that subtree. The following patch moves the declaration from include/linux/sysfs.h to fs/sysfs/sysfs.h, making it clearer that nothing else in the kernel dereferences it. I have been running this patch for years. Please integrate and forward upstream if there are no objections. From: "Adam J. Richter" <adam@yggdrasil.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 13:35:25 +00:00
struct sysfs_dirent {
atomic_t s_count;
struct list_head s_sibling;
struct list_head s_children;
void * s_element;
int s_type;
umode_t s_mode;
sysfs: store sysfs inode nrs in s_ino to avoid readdir oopses Backport of ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22-rc1/2.6.22-rc1-mm1/broken-out/gregkh-driver-sysfs-allocate-inode-number-using-ida.patch For regular files in sysfs, sysfs_readdir wants to traverse sysfs_dirent->s_dentry->d_inode->i_ino to get to the inode number. But, the dentry can be reclaimed under memory pressure, and there is no synchronization with readdir. This patch follows Tejun's scheme of allocating and storing an inode number in the new s_ino member of a sysfs_dirent, when dirents are created, and retrieving it from there for readdir, so that the pointer chain doesn't have to be traversed. Tejun's upstream patch uses a new-ish "ida" allocator which brings along some extra complexity; this -stable patch has a brain-dead incrementing counter which does not guarantee uniqueness, but because sysfs doesn't hash inodes as iunique expects, uniqueness wasn't guaranteed today anyway. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-11 05:02:45 +00:00
ino_t s_ino;
sysfs: move struct sysfs_dirent to private header struct sysfs_dirent is private to the fs/sysfs/ subtree. It is not even referenced as an opaque structure outside of that subtree. The following patch moves the declaration from include/linux/sysfs.h to fs/sysfs/sysfs.h, making it clearer that nothing else in the kernel dereferences it. I have been running this patch for years. Please integrate and forward upstream if there are no objections. From: "Adam J. Richter" <adam@yggdrasil.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 13:35:25 +00:00
struct dentry * s_dentry;
struct iattr * s_iattr;
atomic_t s_event;
};
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
extern struct vfsmount * sysfs_mount;
[PATCH] slab: remove kmem_cache_t Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 04:33:20 +00:00
extern struct kmem_cache *sysfs_dir_cachep;
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
sysfs: Shadow directory support The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*. What I want is a separate /sys/class/net directory in sysfs for each network namespace, and I want to name each of them /sys/class/net. I looked and the VFS actually allows that. All that is needed is for /sys/class/net to implement a follow link method to redirect lookups to the real directory you want. Implementing a follow link method that is sensitive to the current network namespace turns out to be 3 lines of code so it looks like a clean approach. Modifying sysfs so it doesn't get in my was is a bit trickier. I am calling the concept of multiple directories all at the same path in the filesystem shadow directories. With the directory entry really at that location the shadow master. The following patch modifies sysfs so it can handle a directory structure slightly different from the kobject tree so I can implement the shadow directories for handling /sys/class/net/. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-01-24 19:35:52 +00:00
extern void sysfs_delete_inode(struct inode *inode);
[PATCH] sysfs-iattr: set inode attributes o Following patch sets the attributes for newly allocated inodes for sysfs objects. If the object has non-default attributes, inode attributes are set as saved in sysfs_dirent->s_iattr, pointer to struct iattr. Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-31 05:09:52 +00:00
extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
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
extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
sysfs: move release_sysfs_dirent() to dir.c There is no reason this function should be inlined and soon to follow sysfs object reference simplification will make it heavier. Move it to dir.c. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-13 18:45:13 +00:00
extern void release_sysfs_dirent(struct sysfs_dirent * sd);
[PATCH] sysfs: fix problem with duplicate sysfs directories and files The following patch checks for existing sysfs_dirent before preparing new one while creating sysfs directories and files. Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-09 14:10:14 +00:00
extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
sysfs: consolidate sysfs_dirent creation functions Currently there are four functions to create sysfs_dirent - __sysfs_new_dirent(), sysfs_new_dirent(), __sysfs_make_dirent() and sysfs_make_dirent(). Other than sysfs_make_dirent(), no function has two users if calls to implement other functions are excluded. This patch consolidates sysfs_dirent creation functions into the following two. * sysfs_new_dirent() : allocate and initialize * sysfs_attach_dirent() : attach to sysfs_dirent hierarchy and/or associate with dentry This simplifies interface and gives callers more flexibility. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-13 18:45:14 +00:00
extern struct sysfs_dirent *sysfs_new_dirent(void *element, umode_t mode,
int type);
extern void sysfs_attach_dirent(struct sysfs_dirent *sd,
struct sysfs_dirent *parent_sd,
struct dentry *dentry);
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
extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
sysfs_remove_bin_file: no return value, dump_stack on error Make sysfs_remove_bin_file() void. If it detects an error, printk the file name and call dump_stack(). sysfs_hash_and_remove() now returns an error code indicating its success or failure so that sysfs_remove_bin_file() can know success/failure. Convert the only driver that checked the return value of sysfs_remove_bin_file(). Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-07-11 06:05:25 +00:00
extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
[PATCH] sysfs: Allow sysfs attribute files to be pollable It works like this: Open the file Read all the contents. Call poll requesting POLLERR or POLLPRI (so select/exceptfds works) When poll returns, close the file and go to top of loop. or lseek to start of file and go back to the 'read'. Events are signaled by an object manager calling sysfs_notify(kobj, dir, attr); If the dir is non-NULL, it is used to find a subdirectory which contains the attribute (presumably created by sysfs_create_group). This has a cost of one int per attribute, one wait_queuehead per kobject, one int per open file. The name "sysfs_notify" may be confused with the inotify functionality. Maybe it would be nice to support inotify for sysfs attributes as well? This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action to be pollable Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 06:53:53 +00:00
extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
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
extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
extern void sysfs_remove_subdir(struct dentry *);
extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
[PATCH] sysfs-iattr: add sysfs_setattr o This adds ->i_op->setattr VFS method for sysfs inodes. The changed attribues are saved in the persistent sysfs_dirent structure as a pointer to struct iattr. The struct iattr is allocated only for those sysfs_dirent's for which default attributes are getting changed. Thanks to Jon Smirl for this suggestion. Signed-off-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-31 05:09:14 +00:00
extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
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
sysfs: fix race condition around sd->s_dentry, take#2 Allowing attribute and symlink dentries to be reclaimed means sd->s_dentry can change dynamically. However, updates to the field are unsynchronized leading to race conditions. This patch adds sysfs_lock and use it to synchronize updates to sd->s_dentry. Due to the locking around ->d_iput, the check in sysfs_drop_dentry() is complex. sysfs_lock only protect sd->s_dentry pointer itself. The validity of the dentry is protected by dcache_lock, so whether dentry is alive or not can only be tested while holding both locks. This is minimal backport of sysfs_drop_dentry() rewrite in devel branch. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-11 05:04:01 +00:00
extern spinlock_t sysfs_lock;
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
extern struct rw_semaphore sysfs_rename_sem;
extern struct super_block * sysfs_sb;
[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
extern const struct file_operations sysfs_dir_operations;
extern const struct file_operations sysfs_file_operations;
extern const struct file_operations bin_fops;
[PATCH] mark struct inode_operations const 3 Many struct inode_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 08:55:40 +00:00
extern const struct inode_operations sysfs_dir_inode_operations;
extern const struct inode_operations sysfs_symlink_inode_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
struct sysfs_symlink {
char * link_name;
struct kobject * target_kobj;
};
Driver core: fix race in sysfs between sysfs_remove_file() and read()/write() This patch prevents a race between IO and removing a file from sysfs. It introduces a list of sysfs_buffers associated with a file at the inode. Upon removal of a file the list is walked and the buffers marked orphaned. IO to orphaned buffers fails with -ENODEV. The driver can safely free associated data structures or be unloaded. Signed-off-by: Oliver Neukum <oliver@neukum.name> Acked-by: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 09:52:44 +00:00
struct sysfs_buffer {
struct list_head associates;
size_t count;
loff_t pos;
char * page;
struct sysfs_ops * ops;
struct semaphore sem;
int orphaned;
int needs_read_fill;
int event;
};
struct sysfs_buffer_collection {
struct list_head associates;
};
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 inline struct kobject * to_kobj(struct dentry * dentry)
{
struct sysfs_dirent * sd = dentry->d_fsdata;
return ((struct kobject *) sd->s_element);
}
static inline struct attribute * to_attr(struct dentry * dentry)
{
struct sysfs_dirent * sd = dentry->d_fsdata;
return ((struct attribute *) sd->s_element);
}
static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
{
struct sysfs_dirent * sd = dentry->d_fsdata;
return ((struct bin_attribute *) sd->s_element);
}
static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
{
struct kobject * kobj = NULL;
spin_lock(&dcache_lock);
if (!d_unhashed(dentry)) {
struct sysfs_dirent * sd = dentry->d_fsdata;
if (sd->s_type & SYSFS_KOBJ_LINK) {
struct sysfs_symlink * sl = sd->s_element;
kobj = kobject_get(sl->target_kobj);
} else
kobj = kobject_get(sd->s_element);
}
spin_unlock(&dcache_lock);
return kobj;
}
static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
{
if (sd) {
WARN_ON(!atomic_read(&sd->s_count));
atomic_inc(&sd->s_count);
}
return sd;
}
static inline void sysfs_put(struct sysfs_dirent * sd)
{
sysfs: make sysfs_put() ignore NULL sd Make sysfs_put() ignore NULL sd instead of oopsing. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-06-13 18:45:13 +00:00
if (sd && atomic_dec_and_test(&sd->s_count))
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
release_sysfs_dirent(sd);
}
sysfs: Shadow directory support The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*. What I want is a separate /sys/class/net directory in sysfs for each network namespace, and I want to name each of them /sys/class/net. I looked and the VFS actually allows that. All that is needed is for /sys/class/net to implement a follow link method to redirect lookups to the real directory you want. Implementing a follow link method that is sensitive to the current network namespace turns out to be 3 lines of code so it looks like a clean approach. Modifying sysfs so it doesn't get in my was is a bit trickier. I am calling the concept of multiple directories all at the same path in the filesystem shadow directories. With the directory entry really at that location the shadow master. The following patch modifies sysfs so it can handle a directory structure slightly different from the kobject tree so I can implement the shadow directories for handling /sys/class/net/. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Maneesh Soni <maneesh@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-01-24 19:35:52 +00:00
static inline int sysfs_is_shadowed_inode(struct inode *inode)
{
return S_ISDIR(inode->i_mode) && inode->i_op->follow_link;
}
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