block/scsi: Provide a limit on the number of integrity segments

Some controllers have a hardware limit on the number of protection
information scatter-gather list segments they can handle.

Introduce a max_integrity_segments limit in the block layer and provide
a new scsi_host_template setting that allows HBA drivers to provide a
value suitable for the hardware.

Add support for honoring the integrity segment limit when merging both
bios and requests.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
This commit is contained in:
Martin K. Petersen
2010-09-10 20:50:10 +02:00
committed by Jens Axboe
parent c8bf133682
commit 13f05c8d8e
12 changed files with 167 additions and 50 deletions

View File

@@ -496,6 +496,10 @@ static inline struct bio *bio_list_get(struct bio_list *bl)
#define bip_for_each_vec(bvl, bip, i) \
__bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
for_each_bio(_bio) \
bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
#define bio_integrity(bio) (bio->bi_integrity != NULL)
extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *);