diff options
| author | Casey Chen <cachen@purestorage.com> | 2026-05-11 15:22:30 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-05-12 09:23:43 -0600 |
| commit | 2c6e6a18a37b905cb584eb0dda3ae482162a81ca (patch) | |
| tree | 1552c939248b0d00fe17dc4448b727fca40fa186 /block | |
| parent | 637ad3a56a3b889527d1dacea6fea2a8bd648140 (diff) | |
| download | ath-2c6e6a18a37b905cb584eb0dda3ae482162a81ca.tar.gz | |
block: recompute nr_integrity_segments in blk_insert_cloned_request
blk_insert_cloned_request() already recomputes nr_phys_segments
against the bottom queue, because "the queue settings related to
segment counting may differ from the original queue." The exact same
reasoning applies to integrity segments: a stacked driver's underlying
queue can have tighter virt_boundary_mask, seg_boundary_mask, or
max_segment_size than the top queue, in which case
blk_rq_count_integrity_sg() against the bottom queue produces a
different count than the cached rq->nr_integrity_segments inherited
from the source request by blk_rq_prep_clone().
When the cached count is lower than the bottom queue's actual count,
blk_rq_map_integrity_sg() trips
BUG_ON(segments > rq->nr_integrity_segments);
on dispatch. The same families of stacked setups that motivated the
existing nr_phys_segments recompute -- dm-multipath fanning out to
nvme-rdma in particular -- can produce this.
Mirror the nr_phys_segments handling: when the request carries
integrity, recompute nr_integrity_segments against the bottom queue
and reject the request if it exceeds the bottom queue's
max_integrity_segments. blk_rq_count_integrity_sg() and
queue_max_integrity_segments() are both already available via
<linux/blk-integrity.h>, which blk-mq.c includes.
This closes a latent gap in the stacking contract and brings the
integrity-segment accounting in line with the existing
phys-segment accounting.
Fixes: 76c313f658d2 ("blk-integrity: improved sg segment mapping")
Signed-off-by: Casey Chen <cachen@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260511212230.27511-1-cachen@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-mq.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 4c5c16cce4f8f..d0c37daf568f2 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3307,6 +3307,25 @@ blk_status_t blk_insert_cloned_request(struct request *rq) return BLK_STS_IOERR; } + /* + * Integrity segment counting depends on the same queue limits + * (virt_boundary_mask, seg_boundary_mask, max_segment_size) that + * vary across stacked queues, so recompute against the bottom + * queue just like nr_phys_segments above. + */ + if (blk_integrity_rq(rq) && rq->bio) { + unsigned short max_int_segs = queue_max_integrity_segments(q); + + rq->nr_integrity_segments = + blk_rq_count_integrity_sg(rq->q, rq->bio); + if (rq->nr_integrity_segments > max_int_segs) { + printk(KERN_ERR "%s: over max integrity segments limit. (%u > %u)\n", + __func__, rq->nr_integrity_segments, + max_int_segs); + return BLK_STS_IOERR; + } + } + if (q->disk && should_fail_request(q->disk->part0, blk_rq_bytes(rq))) return BLK_STS_IOERR; |