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authorLinus Torvalds <torvalds@linux-foundation.org>2021-08-30 19:24:50 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2021-08-30 19:24:50 +0200
commitaa99f3c2b9c797d8fee28c674a2cbb5adb2ce2ef (patch)
tree98ccf3a82c39f7097111a08cfc7531a41be3ef06 /mm/shmem.c
parentMerge tag 'fs_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git... (diff)
parentfilesystems/locking: fix Malformed table warning (diff)
downloadlinux-aa99f3c2b9c797d8fee28c674a2cbb5adb2ce2ef.tar.xz
linux-aa99f3c2b9c797d8fee28c674a2cbb5adb2ce2ef.zip
Merge tag 'hole_punch_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fs hole punching vs cache filling race fixes from Jan Kara: "Fix races leading to possible data corruption or stale data exposure in multiple filesystems when hole punching races with operations such as readahead. This is the series I was sending for the last merge window but with your objection fixed - now filemap_fault() has been modified to take invalidate_lock only when we need to create new page in the page cache and / or bring it uptodate" * tag 'hole_punch_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: filesystems/locking: fix Malformed table warning cifs: Fix race between hole punch and page fault ceph: Fix race between hole punch and page fault fuse: Convert to using invalidate_lock f2fs: Convert to using invalidate_lock zonefs: Convert to using invalidate_lock xfs: Convert double locking of MMAPLOCK to use VFS helpers xfs: Convert to use invalidate_lock xfs: Refactor xfs_isilocked() ext2: Convert to using invalidate_lock ext4: Convert to use mapping->invalidate_lock mm: Add functions to lock invalidate_lock for two mappings mm: Protect operations adding pages to page cache with invalidate_lock documentation: Sync file_operations members with reality mm: Fix comments mentioning i_mutex
Diffstat (limited to 'mm/shmem.c')
-rw-r--r--mm/shmem.c20
1 files changed, 10 insertions, 10 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index dacda7463d54..3107acee4f71 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -96,7 +96,7 @@ static struct vfsmount *shm_mnt;
/*
* shmem_fallocate communicates with shmem_fault or shmem_writepage via
- * inode->i_private (with i_mutex making sure that it has only one user at
+ * inode->i_private (with i_rwsem making sure that it has only one user at
* a time): we would prefer not to enlarge the shmem inode just for that.
*/
struct shmem_falloc {
@@ -774,7 +774,7 @@ static int shmem_free_swap(struct address_space *mapping,
* Determine (in bytes) how many of the shmem object's pages mapped by the
* given offsets are swapped out.
*
- * This is safe to call without i_mutex or the i_pages lock thanks to RCU,
+ * This is safe to call without i_rwsem or the i_pages lock thanks to RCU,
* as long as the inode doesn't go away and racy results are not a problem.
*/
unsigned long shmem_partial_swap_usage(struct address_space *mapping,
@@ -806,7 +806,7 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping,
* Determine (in bytes) how many of the shmem object's pages mapped by the
* given vma is swapped out.
*
- * This is safe to call without i_mutex or the i_pages lock thanks to RCU,
+ * This is safe to call without i_rwsem or the i_pages lock thanks to RCU,
* as long as the inode doesn't go away and racy results are not a problem.
*/
unsigned long shmem_swap_usage(struct vm_area_struct *vma)
@@ -1069,7 +1069,7 @@ static int shmem_setattr(struct user_namespace *mnt_userns,
loff_t oldsize = inode->i_size;
loff_t newsize = attr->ia_size;
- /* protected by i_mutex */
+ /* protected by i_rwsem */
if ((newsize < oldsize && (info->seals & F_SEAL_SHRINK)) ||
(newsize > oldsize && (info->seals & F_SEAL_GROW)))
return -EPERM;
@@ -2059,7 +2059,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf)
/*
* Trinity finds that probing a hole which tmpfs is punching can
* prevent the hole-punch from ever completing: which in turn
- * locks writers out with its hold on i_mutex. So refrain from
+ * locks writers out with its hold on i_rwsem. So refrain from
* faulting pages into the hole while it's being punched. Although
* shmem_undo_range() does remove the additions, it may be unable to
* keep up, as each new page needs its own unmap_mapping_range() call,
@@ -2070,7 +2070,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf)
* we just need to make racing faults a rare case.
*
* The implementation below would be much simpler if we just used a
- * standard mutex or completion: but we cannot take i_mutex in fault,
+ * standard mutex or completion: but we cannot take i_rwsem in fault,
* and bloating every shmem inode for this unlikely case would be sad.
*/
if (unlikely(inode->i_private)) {
@@ -2470,7 +2470,7 @@ shmem_write_begin(struct file *file, struct address_space *mapping,
struct shmem_inode_info *info = SHMEM_I(inode);
pgoff_t index = pos >> PAGE_SHIFT;
- /* i_mutex is held by caller */
+ /* i_rwsem is held by caller */
if (unlikely(info->seals & (F_SEAL_GROW |
F_SEAL_WRITE | F_SEAL_FUTURE_WRITE))) {
if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE))
@@ -2570,7 +2570,7 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
/*
* We must evaluate after, since reads (unlike writes)
- * are called without i_mutex protection against truncate
+ * are called without i_rwsem protection against truncate
*/
nr = PAGE_SIZE;
i_size = i_size_read(inode);
@@ -2640,7 +2640,7 @@ static loff_t shmem_file_llseek(struct file *file, loff_t offset, int whence)
return -ENXIO;
inode_lock(inode);
- /* We're holding i_mutex so we can access i_size directly */
+ /* We're holding i_rwsem so we can access i_size directly */
offset = mapping_seek_hole_data(mapping, offset, inode->i_size, whence);
if (offset >= 0)
offset = vfs_setpos(file, offset, MAX_LFS_FILESIZE);
@@ -2669,7 +2669,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset,
loff_t unmap_end = round_down(offset + len, PAGE_SIZE) - 1;
DECLARE_WAIT_QUEUE_HEAD_ONSTACK(shmem_falloc_waitq);
- /* protected by i_mutex */
+ /* protected by i_rwsem */
if (info->seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) {
error = -EPERM;
goto out;