4.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Liu Bo <bo.li.liu@xxxxxxxxxx>
commit 0198e5b707cfeb5defbd1b71b1ec6e71580d7db9 upstream.
Bio iterated by set_bio_pages_uptodate() is raid56 internal one, so it
will never be a BIO_CLONED bio, and since this is called by end_io
functions, bio->bi_iter.bi_size is zero, we mustn't use
bio_for_each_segment() as that is a no-op if bi_size is zero.
Fixes: 6592e58c6b68e61f003a01ba29a3716e7e2e9484 ("Btrfs: fix write corruption due to bio cloning on raid5/6")
Signed-off-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/raid56.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1435,14 +1435,13 @@ static int fail_bio_stripe(struct btrfs_
*/
static void set_bio_pages_uptodate(struct bio *bio)
{
- struct bio_vec bvec;
- struct bvec_iter iter;
+ struct bio_vec *bvec;
+ int i;
- if (bio_flagged(bio, BIO_CLONED))
- bio->bi_iter = btrfs_io_bio(bio)->iter;
+ ASSERT(!bio_flagged(bio, BIO_CLONED));
- bio_for_each_segment(bvec, bio, iter)
- SetPageUptodate(bvec.bv_page);
+ bio_for_each_segment_all(bvec, bio, i)
+ SetPageUptodate(bvec->bv_page);
}
/*