diff options
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/extent_io.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 2776112dbdf8..87f487b11657 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2773,13 +2773,19 @@ static int fiemap_next_leaf_item(struct btrfs_inode *inode, struct btrfs_path *p goto out; } - /* See the comment at fiemap_search_slot() about why we clone. */ - copy_extent_buffer_full(clone, path->nodes[0]); /* * Important to preserve the start field, for the optimizations when * checking if extents are shared (see extent_fiemap()). + * + * We must set ->start before calling copy_extent_buffer_full(). If we + * are on sub-pagesize blocksize, we use ->start to determine the offset + * into the folio where our eb exists, and if we update ->start after + * the fact then any subsequent reads of the eb may read from a + * different offset in the folio than where we originally copied into. */ clone->start = path->nodes[0]->start; + /* See the comment at fiemap_search_slot() about why we clone. */ + copy_extent_buffer_full(clone, path->nodes[0]); slot = path->slots[0]; btrfs_release_path(path); |