summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorUday Shankar <ushankar@purestorage.com>2023-02-28 17:06:55 -0700
committerJens Axboe <axboe@kernel.dk>2023-03-02 21:00:20 -0700
commit49d24398327e32265eccdeec4baeb5a6a609c0bd (patch)
treeeac5516659021cb104b90d7b398f18843ff84d8a
parent326ac2c5133e5da7ccdd08d4f9c562f2323021aa (diff)
blk-mq: enforce op-specific segment limits in blk_insert_cloned_request
The block layer might merge together discard requests up until the max_discard_segments limit is hit, but blk_insert_cloned_request checks the segment count against max_segments regardless of the req op. This can result in errors like the following when discards are issued through a DM device and max_discard_segments exceeds max_segments for the queue of the chosen underlying device. blk_insert_cloned_request: over max segments limit. (256 > 129) Fix this by looking at the req_op and enforcing the appropriate segment limit - max_discard_segments for REQ_OP_DISCARDs and max_segments for everything else. Signed-off-by: Uday Shankar <ushankar@purestorage.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20230301000655.48112-1-ushankar@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r--block/blk-merge.c7
-rw-r--r--block/blk-mq.c7
-rw-r--r--block/blk.h7
3 files changed, 11 insertions, 10 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 808b58129d3e..ff72edd7ee03 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -586,13 +586,6 @@ int __blk_rq_map_sg(struct request_queue *q, struct request *rq,
}
EXPORT_SYMBOL(__blk_rq_map_sg);
-static inline unsigned int blk_rq_get_max_segments(struct request *rq)
-{
- if (req_op(rq) == REQ_OP_DISCARD)
- return queue_max_discard_segments(rq->q);
- return queue_max_segments(rq->q);
-}
-
static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
sector_t offset)
{
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 08093d4348dd..7c6f812323af 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3000,6 +3000,7 @@ blk_status_t blk_insert_cloned_request(struct request *rq)
{
struct request_queue *q = rq->q;
unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(rq));
+ unsigned int max_segments = blk_rq_get_max_segments(rq);
blk_status_t ret;
if (blk_rq_sectors(rq) > max_sectors) {
@@ -3026,9 +3027,9 @@ blk_status_t blk_insert_cloned_request(struct request *rq)
* original queue.
*/
rq->nr_phys_segments = blk_recalc_rq_segments(rq);
- if (rq->nr_phys_segments > queue_max_segments(q)) {
- printk(KERN_ERR "%s: over max segments limit. (%hu > %hu)\n",
- __func__, rq->nr_phys_segments, queue_max_segments(q));
+ if (rq->nr_phys_segments > max_segments) {
+ printk(KERN_ERR "%s: over max segments limit. (%u > %u)\n",
+ __func__, rq->nr_phys_segments, max_segments);
return BLK_STS_IOERR;
}
diff --git a/block/blk.h b/block/blk.h
index e835f21d48af..cc4e8873dfde 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -156,6 +156,13 @@ static inline bool blk_discard_mergable(struct request *req)
return false;
}
+static inline unsigned int blk_rq_get_max_segments(struct request *rq)
+{
+ if (req_op(rq) == REQ_OP_DISCARD)
+ return queue_max_discard_segments(rq->q);
+ return queue_max_segments(rq->q);
+}
+
static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
enum req_op op)
{