On 2021/4/8 下午8:40, Goldwyn Rodrigues wrote:
try_lock_extent() returns 1 on success or 0 for failure and not an error
code. If try_lock_extent() fails, read_extent_buffer_subpage() returns
zero indicating subpage extent read success.
Return EAGAIN/EWOULDBLOCK if try_lock_extent() fails in locking the
extent.
Signed-off-by: Goldwyn Rodrigues <[email protected]>
Reviewed-by: Qu Wenruo <[email protected]>
Thankfully the only metadata reader who will pass wait == WAIT_NONE is
readahead, so no real damage.
But still a nice fix!
Thanks,
Qu
---
fs/btrfs/extent_io.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 7ad2169e7487..3536feedd6c5 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5914,10 +5914,8 @@ static int read_extent_buffer_subpage(struct
extent_buffer *eb, int wait,
io_tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
if (wait == WAIT_NONE) {
- ret = try_lock_extent(io_tree, eb->start,
- eb->start + eb->len - 1);
- if (ret <= 0)
- return ret;
+ if (!try_lock_extent(io_tree, eb->start, eb->start + eb->len -
1))
+ return -EAGAIN;
} else {
ret = lock_extent(io_tree, eb->start, eb->start + eb->len - 1);
if (ret < 0)
