diff options
Diffstat (limited to 'fs/btrfs/file.c')
| -rw-r--r-- | fs/btrfs/file.c | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index c5e36f58eb07..4fb521d91b06 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3485,7 +3485,7 @@ static bool find_desired_extent_in_hole(struct btrfs_inode *inode, int whence, static loff_t find_desired_extent(struct file *file, loff_t offset, int whence) { struct btrfs_inode *inode = BTRFS_I(file->f_mapping->host); - struct btrfs_file_private *private = file->private_data; + struct btrfs_file_private *private; struct btrfs_fs_info *fs_info = inode->root->fs_info; struct extent_state *cached_state = NULL; struct extent_state **delalloc_cached_state; @@ -3513,7 +3513,19 @@ static loff_t find_desired_extent(struct file *file, loff_t offset, int whence) inode_get_bytes(&inode->vfs_inode) == i_size) return i_size; - if (!private) { + spin_lock(&inode->lock); + private = file->private_data; + spin_unlock(&inode->lock); + + if (private && private->owner_task != current) { + /* + * Not allocated by us, don't use it as its cached state is used + * by the task that allocated it and we don't want neither to + * mess with it nor get incorrect results because it reflects an + * invalid state for the current task. + */ + private = NULL; + } else if (!private) { private = kzalloc(sizeof(*private), GFP_KERNEL); /* * No worries if memory allocation failed. @@ -3521,7 +3533,23 @@ static loff_t find_desired_extent(struct file *file, loff_t offset, int whence) * lseek SEEK_HOLE/DATA calls to a file when there's delalloc, * so everything will still be correct. */ - file->private_data = private; + if (private) { + bool free = false; + + private->owner_task = current; + + spin_lock(&inode->lock); + if (file->private_data) + free = true; + else + file->private_data = private; + spin_unlock(&inode->lock); + + if (free) { + kfree(private); + private = NULL; + } + } } if (private) |