scsi: Introduce scsi_mq_sgl_size()

This patch does not change any functionality but makes the next patch
easier to read.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Bart Van Assche 2017-06-02 14:21:59 -07:00 committed by Martin K. Petersen
parent 2dd6fb5957
commit be4c186c80

View file

@ -1859,6 +1859,13 @@ static inline int prep_to_mq(int ret)
}
}
/* Size in bytes of the sg-list stored in the scsi-mq command-private data. */
static unsigned int scsi_mq_sgl_size(struct Scsi_Host *shost)
{
return min_t(unsigned int, shost->sg_tablesize, SG_CHUNK_SIZE) *
sizeof(struct scatterlist);
}
static int scsi_mq_prep_fn(struct request *req)
{
struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
@ -1893,10 +1900,7 @@ static int scsi_mq_prep_fn(struct request *req)
cmd->sdb.table.sgl = sg;
if (scsi_host_get_prot(shost)) {
cmd->prot_sdb = (void *)sg +
min_t(unsigned int,
shost->sg_tablesize, SG_CHUNK_SIZE) *
sizeof(struct scatterlist);
cmd->prot_sdb = (void *)sg + scsi_mq_sgl_size(shost);
memset(cmd->prot_sdb, 0, sizeof(struct scsi_data_buffer));
cmd->prot_sdb->table.sgl =
@ -2202,12 +2206,9 @@ struct request_queue *scsi_mq_alloc_queue(struct scsi_device *sdev)
int scsi_mq_setup_tags(struct Scsi_Host *shost)
{
unsigned int cmd_size, sgl_size, tbl_size;
unsigned int cmd_size, sgl_size;
tbl_size = shost->sg_tablesize;
if (tbl_size > SG_CHUNK_SIZE)
tbl_size = SG_CHUNK_SIZE;
sgl_size = tbl_size * sizeof(struct scatterlist);
sgl_size = scsi_mq_sgl_size(shost);
cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size + sgl_size;
if (scsi_host_get_prot(shost))
cmd_size += sizeof(struct scsi_data_buffer) + sgl_size;