linux/fs/orangefs/file.c
Martin Brandenburg a5135eeab2 orangefs: implement vm_ops->fault
Must retrieve size before running filemap_fault so the kernel has
an up-to-date size.

This should have been caught by xfstests generic/246, but it was masked
by orangefs_new_inode, which set i_size to PAGE_SIZE.  When nothing
caused a getattr prior to a pagefault, i_size was still PAGE_SIZE.
Since xfstests only read 10 bytes, it did not catch this bug.

When orangefs_new_inode was modified to perform a getattr instead,
i_size was set to zero, as it was a newly created file.  Then
orangefs_file_write_iter did NOT set i_size.  Instead it invalidated the
attribute cache, which should have caused the next caller to retrieve
i_size.  But the fault handler did not know it was supposed to retrieve
i_size.  So during xfstests, i_size was still zero, and filemap_fault
returned VM_FAULT_SIGBUS.

Fixes xfstests generic/452.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2018-04-03 21:55:27 -04:00

718 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* (C) 2001 Clemson University and The University of Chicago
*
* See COPYING in top-level directory.
*/
/*
* Linux VFS file operations.
*/
#include "protocol.h"
#include "orangefs-kernel.h"
#include "orangefs-bufmap.h"
#include <linux/fs.h>
#include <linux/pagemap.h>
static int flush_racache(struct inode *inode)
{
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
struct orangefs_kernel_op_s *new_op;
int ret;
gossip_debug(GOSSIP_UTILS_DEBUG,
"%s: %pU: Handle is %pU | fs_id %d\n", __func__,
get_khandle_from_ino(inode), &orangefs_inode->refn.khandle,
orangefs_inode->refn.fs_id);
new_op = op_alloc(ORANGEFS_VFS_OP_RA_FLUSH);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.ra_cache_flush.refn = orangefs_inode->refn;
ret = service_operation(new_op, "orangefs_flush_racache",
get_interruptible_flag(inode));
gossip_debug(GOSSIP_UTILS_DEBUG, "%s: got return value of %d\n",
__func__, ret);
op_release(new_op);
return ret;
}
/*
* Post and wait for the I/O upcall to finish
*/
static ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode,
loff_t *offset, struct iov_iter *iter,
size_t total_size, loff_t readahead_size)
{
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
struct orangefs_kernel_op_s *new_op = NULL;
int buffer_index = -1;
ssize_t ret;
new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO);
if (!new_op)
return -ENOMEM;
/* synchronous I/O */
new_op->upcall.req.io.readahead_size = readahead_size;
new_op->upcall.req.io.io_type = type;
new_op->upcall.req.io.refn = orangefs_inode->refn;
populate_shared_memory:
/* get a shared buffer index */
buffer_index = orangefs_bufmap_get();
if (buffer_index < 0) {
ret = buffer_index;
gossip_debug(GOSSIP_FILE_DEBUG,
"%s: orangefs_bufmap_get failure (%zd)\n",
__func__, ret);
goto out;
}
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): GET op %p -> buffer_index %d\n",
__func__,
handle,
new_op,
buffer_index);
new_op->uses_shared_memory = 1;
new_op->upcall.req.io.buf_index = buffer_index;
new_op->upcall.req.io.count = total_size;
new_op->upcall.req.io.offset = *offset;
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): offset: %llu total_size: %zd\n",
__func__,
handle,
llu(*offset),
total_size);
/*
* Stage 1: copy the buffers into client-core's address space
*/
if (type == ORANGEFS_IO_WRITE && total_size) {
ret = orangefs_bufmap_copy_from_iovec(iter, buffer_index,
total_size);
if (ret < 0) {
gossip_err("%s: Failed to copy-in buffers. Please make sure that the pvfs2-client is running. %ld\n",
__func__, (long)ret);
goto out;
}
}
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): Calling post_io_request with tag (%llu)\n",
__func__,
handle,
llu(new_op->tag));
/* Stage 2: Service the I/O operation */
ret = service_operation(new_op,
type == ORANGEFS_IO_WRITE ?
"file_write" :
"file_read",
get_interruptible_flag(inode));
/*
* If service_operation() returns -EAGAIN #and# the operation was
* purged from orangefs_request_list or htable_ops_in_progress, then
* we know that the client was restarted, causing the shared memory
* area to be wiped clean. To restart a write operation in this
* case, we must re-copy the data from the user's iovec to a NEW
* shared memory location. To restart a read operation, we must get
* a new shared memory location.
*/
if (ret == -EAGAIN && op_state_purged(new_op)) {
orangefs_bufmap_put(buffer_index);
buffer_index = -1;
if (type == ORANGEFS_IO_WRITE)
iov_iter_revert(iter, total_size);
gossip_debug(GOSSIP_FILE_DEBUG,
"%s:going to repopulate_shared_memory.\n",
__func__);
goto populate_shared_memory;
}
if (ret < 0) {
if (ret == -EINTR) {
/*
* We can't return EINTR if any data was written,
* it's not POSIX. It is minimally acceptable
* to give a partial write, the way NFS does.
*
* It would be optimal to return all or nothing,
* but if a userspace write is bigger than
* an IO buffer, and the interrupt occurs
* between buffer writes, that would not be
* possible.
*/
switch (new_op->op_state - OP_VFS_STATE_GIVEN_UP) {
/*
* If the op was waiting when the interrupt
* occurred, then the client-core did not
* trigger the write.
*/
case OP_VFS_STATE_WAITING:
if (*offset == 0)
ret = -EINTR;
else
ret = 0;
break;
/*
* If the op was in progress when the interrupt
* occurred, then the client-core was able to
* trigger the write.
*/
case OP_VFS_STATE_INPROGR:
ret = total_size;
break;
default:
gossip_err("%s: unexpected op state :%d:.\n",
__func__,
new_op->op_state);
ret = 0;
break;
}
gossip_debug(GOSSIP_FILE_DEBUG,
"%s: got EINTR, state:%d: %p\n",
__func__,
new_op->op_state,
new_op);
} else {
gossip_err("%s: error in %s handle %pU, returning %zd\n",
__func__,
type == ORANGEFS_IO_READ ?
"read from" : "write to",
handle, ret);
}
if (orangefs_cancel_op_in_progress(new_op))
return ret;
goto out;
}
/*
* Stage 3: Post copy buffers from client-core's address space
*/
if (type == ORANGEFS_IO_READ && new_op->downcall.resp.io.amt_complete) {
/*
* NOTE: the iovector can either contain addresses which
* can futher be kernel-space or user-space addresses.
* or it can pointers to struct page's
*/
ret = orangefs_bufmap_copy_to_iovec(iter, buffer_index,
new_op->downcall.resp.io.amt_complete);
if (ret < 0) {
gossip_err("%s: Failed to copy-out buffers. Please make sure that the pvfs2-client is running (%ld)\n",
__func__, (long)ret);
goto out;
}
}
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): Amount %s, returned by the sys-io call:%d\n",
__func__,
handle,
type == ORANGEFS_IO_READ ? "read" : "written",
(int)new_op->downcall.resp.io.amt_complete);
ret = new_op->downcall.resp.io.amt_complete;
out:
if (buffer_index >= 0) {
orangefs_bufmap_put(buffer_index);
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): PUT buffer_index %d\n",
__func__, handle, buffer_index);
buffer_index = -1;
}
op_release(new_op);
return ret;
}
/*
* Common entry point for read/write/readv/writev
* This function will dispatch it to either the direct I/O
* or buffered I/O path depending on the mount options and/or
* augmented/extended metadata attached to the file.
* Note: File extended attributes override any mount options.
*/
static ssize_t do_readv_writev(enum ORANGEFS_io_type type, struct file *file,
loff_t *offset, struct iov_iter *iter)
{
struct inode *inode = file->f_mapping->host;
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
struct orangefs_khandle *handle = &orangefs_inode->refn.khandle;
size_t count = iov_iter_count(iter);
ssize_t total_count = 0;
ssize_t ret = -EINVAL;
gossip_debug(GOSSIP_FILE_DEBUG,
"%s-BEGIN(%pU): count(%d) after estimate_max_iovecs.\n",
__func__,
handle,
(int)count);
if (type == ORANGEFS_IO_WRITE) {
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): proceeding with offset : %llu, "
"size %d\n",
__func__,
handle,
llu(*offset),
(int)count);
}
if (count == 0) {
ret = 0;
goto out;
}
while (iov_iter_count(iter)) {
size_t each_count = iov_iter_count(iter);
size_t amt_complete;
/* how much to transfer in this loop iteration */
if (each_count > orangefs_bufmap_size_query())
each_count = orangefs_bufmap_size_query();
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): size of each_count(%d)\n",
__func__,
handle,
(int)each_count);
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): BEFORE wait_for_io: offset is %d\n",
__func__,
handle,
(int)*offset);
ret = wait_for_direct_io(type, inode, offset, iter,
each_count, 0);
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): return from wait_for_io:%d\n",
__func__,
handle,
(int)ret);
if (ret < 0)
goto out;
*offset += ret;
total_count += ret;
amt_complete = ret;
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): AFTER wait_for_io: offset is %d\n",
__func__,
handle,
(int)*offset);
/*
* if we got a short I/O operations,
* fall out and return what we got so far
*/
if (amt_complete < each_count)
break;
} /*end while */
out:
if (total_count > 0)
ret = total_count;
if (ret > 0) {
if (type == ORANGEFS_IO_READ) {
file_accessed(file);
} else {
file_update_time(file);
/*
* Must invalidate to ensure write loop doesn't
* prevent kernel from reading updated
* attribute. Size probably changed because of
* the write, and other clients could update
* any other attribute.
*/
orangefs_inode->getattr_time = jiffies - 1;
}
}
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): Value(%d) returned.\n",
__func__,
handle,
(int)ret);
return ret;
}
/*
* Read data from a specified offset in a file (referenced by inode).
* Data may be placed either in a user or kernel buffer.
*/
ssize_t orangefs_inode_read(struct inode *inode,
struct iov_iter *iter,
loff_t *offset,
loff_t readahead_size)
{
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode);
size_t count = iov_iter_count(iter);
size_t bufmap_size;
ssize_t ret = -EINVAL;
orangefs_stats.reads++;
bufmap_size = orangefs_bufmap_size_query();
if (count > bufmap_size) {
gossip_debug(GOSSIP_FILE_DEBUG,
"%s: count is too large (%zd/%zd)!\n",
__func__, count, bufmap_size);
return -EINVAL;
}
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU) %zd@%llu\n",
__func__,
&orangefs_inode->refn.khandle,
count,
llu(*offset));
ret = wait_for_direct_io(ORANGEFS_IO_READ, inode, offset, iter,
count, readahead_size);
if (ret > 0)
*offset += ret;
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): Value(%zd) returned.\n",
__func__,
&orangefs_inode->refn.khandle,
ret);
return ret;
}
static ssize_t orangefs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
{
struct file *file = iocb->ki_filp;
loff_t pos = iocb->ki_pos;
ssize_t rc = 0;
BUG_ON(iocb->private);
gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_file_read_iter\n");
orangefs_stats.reads++;
rc = do_readv_writev(ORANGEFS_IO_READ, file, &pos, iter);
iocb->ki_pos = pos;
return rc;
}
static ssize_t orangefs_file_write_iter(struct kiocb *iocb, struct iov_iter *iter)
{
struct file *file = iocb->ki_filp;
loff_t pos;
ssize_t rc;
BUG_ON(iocb->private);
gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_file_write_iter\n");
inode_lock(file->f_mapping->host);
/* Make sure generic_write_checks sees an up to date inode size. */
if (file->f_flags & O_APPEND) {
rc = orangefs_inode_getattr(file->f_mapping->host, 0, 1,
STATX_SIZE);
if (rc == -ESTALE)
rc = -EIO;
if (rc) {
gossip_err("%s: orangefs_inode_getattr failed, "
"rc:%zd:.\n", __func__, rc);
goto out;
}
}
rc = generic_write_checks(iocb, iter);
if (rc <= 0) {
gossip_err("%s: generic_write_checks failed, rc:%zd:.\n",
__func__, rc);
goto out;
}
/*
* if we are appending, generic_write_checks would have updated
* pos to the end of the file, so we will wait till now to set
* pos...
*/
pos = iocb->ki_pos;
rc = do_readv_writev(ORANGEFS_IO_WRITE,
file,
&pos,
iter);
if (rc < 0) {
gossip_err("%s: do_readv_writev failed, rc:%zd:.\n",
__func__, rc);
goto out;
}
iocb->ki_pos = pos;
orangefs_stats.writes++;
out:
inode_unlock(file->f_mapping->host);
return rc;
}
/*
* Perform a miscellaneous operation on a file.
*/
static long orangefs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
int ret = -ENOTTY;
__u64 val = 0;
unsigned long uval;
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_ioctl: called with cmd %d\n",
cmd);
/*
* we understand some general ioctls on files, such as the immutable
* and append flags
*/
if (cmd == FS_IOC_GETFLAGS) {
val = 0;
ret = orangefs_inode_getxattr(file_inode(file),
"user.pvfs2.meta_hint",
&val, sizeof(val));
if (ret < 0 && ret != -ENODATA)
return ret;
else if (ret == -ENODATA)
val = 0;
uval = val;
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_ioctl: FS_IOC_GETFLAGS: %llu\n",
(unsigned long long)uval);
return put_user(uval, (int __user *)arg);
} else if (cmd == FS_IOC_SETFLAGS) {
ret = 0;
if (get_user(uval, (int __user *)arg))
return -EFAULT;
/*
* ORANGEFS_MIRROR_FL is set internally when the mirroring mode
* is turned on for a file. The user is not allowed to turn
* on this bit, but the bit is present if the user first gets
* the flags and then updates the flags with some new
* settings. So, we ignore it in the following edit. bligon.
*/
if ((uval & ~ORANGEFS_MIRROR_FL) &
(~(FS_IMMUTABLE_FL | FS_APPEND_FL | FS_NOATIME_FL))) {
gossip_err("orangefs_ioctl: the FS_IOC_SETFLAGS only supports setting one of FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NOATIME_FL\n");
return -EINVAL;
}
val = uval;
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_ioctl: FS_IOC_SETFLAGS: %llu\n",
(unsigned long long)val);
ret = orangefs_inode_setxattr(file_inode(file),
"user.pvfs2.meta_hint",
&val, sizeof(val), 0);
}
return ret;
}
static int orangefs_fault(struct vm_fault *vmf)
{
struct file *file = vmf->vma->vm_file;
int rc;
rc = orangefs_inode_getattr(file->f_mapping->host, 0, 1,
STATX_SIZE);
if (rc == -ESTALE)
rc = -EIO;
if (rc) {
gossip_err("%s: orangefs_inode_getattr failed, "
"rc:%d:.\n", __func__, rc);
return rc;
}
return filemap_fault(vmf);
}
const struct vm_operations_struct orangefs_file_vm_ops = {
.fault = orangefs_fault,
.map_pages = filemap_map_pages,
.page_mkwrite = filemap_page_mkwrite,
};
/*
* Memory map a region of a file.
*/
static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_file_mmap: called on %s\n",
(file ?
(char *)file->f_path.dentry->d_name.name :
(char *)"Unknown"));
if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE))
return -EINVAL;
/* set the sequential readahead hint */
vma->vm_flags |= VM_SEQ_READ;
vma->vm_flags &= ~VM_RAND_READ;
file_accessed(file);
vma->vm_ops = &orangefs_file_vm_ops;
return 0;
}
#define mapping_nrpages(idata) ((idata)->nrpages)
/*
* Called to notify the module that there are no more references to
* this file (i.e. no processes have it open).
*
* \note Not called when each file is closed.
*/
static int orangefs_file_release(struct inode *inode, struct file *file)
{
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_file_release: called on %pD\n",
file);
/*
* remove all associated inode pages from the page cache and
* readahead cache (if any); this forces an expensive refresh of
* data for the next caller of mmap (or 'get_block' accesses)
*/
if (file_inode(file) &&
file_inode(file)->i_mapping &&
mapping_nrpages(&file_inode(file)->i_data)) {
if (orangefs_features & ORANGEFS_FEATURE_READAHEAD) {
gossip_debug(GOSSIP_INODE_DEBUG,
"calling flush_racache on %pU\n",
get_khandle_from_ino(inode));
flush_racache(inode);
gossip_debug(GOSSIP_INODE_DEBUG,
"flush_racache finished\n");
}
truncate_inode_pages(file_inode(file)->i_mapping,
0);
}
return 0;
}
/*
* Push all data for a specific file onto permanent storage.
*/
static int orangefs_fsync(struct file *file,
loff_t start,
loff_t end,
int datasync)
{
int ret;
struct orangefs_inode_s *orangefs_inode =
ORANGEFS_I(file_inode(file));
struct orangefs_kernel_op_s *new_op = NULL;
new_op = op_alloc(ORANGEFS_VFS_OP_FSYNC);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.fsync.refn = orangefs_inode->refn;
ret = service_operation(new_op,
"orangefs_fsync",
get_interruptible_flag(file_inode(file)));
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_fsync got return value of %d\n",
ret);
op_release(new_op);
return ret;
}
/*
* Change the file pointer position for an instance of an open file.
*
* \note If .llseek is overriden, we must acquire lock as described in
* Documentation/filesystems/Locking.
*
* Future upgrade could support SEEK_DATA and SEEK_HOLE but would
* require much changes to the FS
*/
static loff_t orangefs_file_llseek(struct file *file, loff_t offset, int origin)
{
int ret = -EINVAL;
struct inode *inode = file_inode(file);
if (origin == SEEK_END) {
/*
* revalidate the inode's file size.
* NOTE: We are only interested in file size here,
* so we set mask accordingly.
*/
ret = orangefs_inode_getattr(file->f_mapping->host, 0, 1,
STATX_SIZE);
if (ret == -ESTALE)
ret = -EIO;
if (ret) {
gossip_debug(GOSSIP_FILE_DEBUG,
"%s:%s:%d calling make bad inode\n",
__FILE__,
__func__,
__LINE__);
return ret;
}
}
gossip_debug(GOSSIP_FILE_DEBUG,
"orangefs_file_llseek: offset is %ld | origin is %d"
" | inode size is %lu\n",
(long)offset,
origin,
(unsigned long)i_size_read(inode));
return generic_file_llseek(file, offset, origin);
}
/*
* Support local locks (locks that only this kernel knows about)
* if Orangefs was mounted -o local_lock.
*/
static int orangefs_lock(struct file *filp, int cmd, struct file_lock *fl)
{
int rc = -EINVAL;
if (ORANGEFS_SB(file_inode(filp)->i_sb)->flags & ORANGEFS_OPT_LOCAL_LOCK) {
if (cmd == F_GETLK) {
rc = 0;
posix_test_lock(filp, fl);
} else {
rc = posix_lock_file(filp, fl, NULL);
}
}
return rc;
}
/** ORANGEFS implementation of VFS file operations */
const struct file_operations orangefs_file_operations = {
.llseek = orangefs_file_llseek,
.read_iter = orangefs_file_read_iter,
.write_iter = orangefs_file_write_iter,
.lock = orangefs_lock,
.unlocked_ioctl = orangefs_ioctl,
.mmap = orangefs_file_mmap,
.open = generic_file_open,
.release = orangefs_file_release,
.fsync = orangefs_fsync,
};