diff options
| -rw-r--r-- | fs/btrfs/ioctl.c | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index fba7a004e7e5..362720a3fea2 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3410,15 +3410,41 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, goto out_unlock; } - /* truncate page cache pages from target inode range */ - truncate_inode_pages_range(&inode->i_data, destoff, - PAGE_CACHE_ALIGN(destoff + len) - 1); + /* + * Lock the target range too. Right after we replace the file extent + * items in the fs tree (which now point to the cloned data), we might + * have a worker replace them with extent items relative to a write + * operation that was issued before this clone operation (i.e. confront + * with inode.c:btrfs_finish_ordered_io). + */ + if (same_inode) { + u64 lock_start = min_t(u64, off, destoff); + u64 lock_len = max_t(u64, off, destoff) + len - lock_start; - lock_extent_range(src, off, len); + lock_extent_range(src, lock_start, lock_len); + } else { + lock_extent_range(src, off, len); + lock_extent_range(inode, destoff, len); + } ret = btrfs_clone(src, inode, off, olen, len, destoff); - unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); + if (same_inode) { + u64 lock_start = min_t(u64, off, destoff); + u64 lock_end = max_t(u64, off, destoff) + len - 1; + + unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end); + } else { + unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1); + unlock_extent(&BTRFS_I(inode)->io_tree, destoff, + destoff + len - 1); + } + /* + * Truncate page cache pages so that future reads will see the cloned + * data immediately and not the previous data. + */ + truncate_inode_pages_range(&inode->i_data, destoff, + PAGE_CACHE_ALIGN(destoff + len) - 1); out_unlock: if (!same_inode) { if (inode < src) { |
