4.15-stable review patch. If anyone has any objections, please let me know.
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From: Liu Bo bo.li.liu@oracle.com
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@oracle.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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); }
/*