Filipe David Borba Manana
2014-Apr-26 00:35 UTC
[PATCH] Btrfs: read inode size after acquiring the mutex when punching a hole
In a previous change, commit 12870f1c9b2de7d475d22e73fd7db1b418599725, I accidentally moved the roundup of inode->i_size to outside of the critical section delimited by the inode mutex, which is not atomic and not correct since the size can be changed by other task before we acquire the mutex. Therefore fix it. Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> --- fs/btrfs/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 23f6a9d..efaad37 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2192,13 +2192,14 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) bool same_page = ((offset >> PAGE_CACHE_SHIFT) = ((offset + len - 1) >> PAGE_CACHE_SHIFT)); bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES); - u64 ino_size = round_up(inode->i_size, PAGE_CACHE_SIZE); + u64 ino_size; ret = btrfs_wait_ordered_range(inode, offset, len); if (ret) return ret; mutex_lock(&inode->i_mutex); + ino_size = round_up(inode->i_size, PAGE_CACHE_SIZE); /* * We needn't truncate any page which is beyond the end of the file * because we are sure there is no data there. -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html