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>
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index b7bdecb..d0a6a84 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -388,6 +388,7 @@
* of scatter-gather.
*/
unsigned short sg_tablesize;
+ unsigned short sg_prot_tablesize;
/*
* Set this if the host adapter has limitations beside segment count.
@@ -599,6 +600,7 @@
int can_queue;
short cmd_per_lun;
short unsigned int sg_tablesize;
+ short unsigned int sg_prot_tablesize;
short unsigned int max_sectors;
unsigned long dma_boundary;
/*
@@ -823,6 +825,11 @@
return shost->prot_capabilities;
}
+static inline int scsi_host_prot_dma(struct Scsi_Host *shost)
+{
+ return shost->prot_capabilities >= SHOST_DIX_TYPE0_PROTECTION;
+}
+
static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsigned int target_type)
{
static unsigned char cap[] = { 0,