summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorShaohua Li <shli@kernel.org>2012-09-28 10:38:48 +0200
committerJens Axboe <axboe@kernel.dk>2012-09-28 10:38:48 +0200
commit02f3939e1a9357b7c370a4a69717cf9c02452737 (patch)
treee7cc574ca11f44ccdf6a685dc45a9a1eede1f2cd
parent232f1b51062553b7cf49f99719fbd1b8a8d80f29 (diff)
downloadlinux-bcache-02f3939e1a9357b7c370a4a69717cf9c02452737.tar.zst
block: makes bio_split support bio without datafor-3.7/core
discard bio hasn't data attached. We hit a BUG_ON with such bio. This makes bio_split works for such bio. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r--fs/bio.c26
1 files changed, 14 insertions, 12 deletions
diff --git a/fs/bio.c b/fs/bio.c
index f855e0e1869c..9298c65ad9c7 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -1475,7 +1475,7 @@ struct bio_pair *bio_split(struct bio *bi, int first_sectors)
trace_block_split(bdev_get_queue(bi->bi_bdev), bi,
bi->bi_sector + first_sectors);
- BUG_ON(bi->bi_vcnt != 1);
+ BUG_ON(bi->bi_vcnt != 1 && bi->bi_vcnt != 0);
BUG_ON(bi->bi_idx != 0);
atomic_set(&bp->cnt, 3);
bp->error = 0;
@@ -1485,20 +1485,22 @@ struct bio_pair *bio_split(struct bio *bi, int first_sectors)
bp->bio2.bi_size -= first_sectors << 9;
bp->bio1.bi_size = first_sectors << 9;
- bp->bv1 = bi->bi_io_vec[0];
- bp->bv2 = bi->bi_io_vec[0];
+ if (bi->bi_vcnt != 0) {
+ bp->bv1 = bi->bi_io_vec[0];
+ bp->bv2 = bi->bi_io_vec[0];
- if (bio_is_rw(bi)) {
- bp->bv2.bv_offset += first_sectors << 9;
- bp->bv2.bv_len -= first_sectors << 9;
- bp->bv1.bv_len = first_sectors << 9;
- }
+ if (bio_is_rw(bi)) {
+ bp->bv2.bv_offset += first_sectors << 9;
+ bp->bv2.bv_len -= first_sectors << 9;
+ bp->bv1.bv_len = first_sectors << 9;
+ }
- bp->bio1.bi_io_vec = &bp->bv1;
- bp->bio2.bi_io_vec = &bp->bv2;
+ bp->bio1.bi_io_vec = &bp->bv1;
+ bp->bio2.bi_io_vec = &bp->bv2;
- bp->bio1.bi_max_vecs = 1;
- bp->bio2.bi_max_vecs = 1;
+ bp->bio1.bi_max_vecs = 1;
+ bp->bio2.bi_max_vecs = 1;
+ }
bp->bio1.bi_end_io = bio_pair_end_1;
bp->bio2.bi_end_io = bio_pair_end_2;