diff options
Diffstat (limited to 'fs/btrfs/extent_io.c')
| -rw-r--r-- | fs/btrfs/extent_io.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 40d3bca6aaa4..4be117adda33 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -5853,6 +5853,13 @@ int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num) for (i = 0; i < num_pages; i++) { page = eb->pages[i]; if (wait == WAIT_NONE) { + /* + * WAIT_NONE is only utilized by readahead. If we can't + * acquire the lock atomically it means either the eb + * is being read out or under modification. + * Either way the eb will be or has been cached, + * readahead can exit safely. + */ if (!trylock_page(page)) goto unlock_exit; } else { |