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>
}
EXPORT_SYMBOL(__blk_rq_map_sg);
}
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)
{
static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
sector_t offset)
{
{
struct request_queue *q = rq->q;
unsigned int max_sectors = blk_queue_get_max_sectors(q, req_op(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) {
blk_status_t ret;
if (blk_rq_sectors(rq) > max_sectors) {
* original queue.
*/
rq->nr_phys_segments = blk_recalc_rq_segments(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);
+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)
{
static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
enum req_op op)
{