scsi: introduce a max_segment_size host_template parameters

This allows the host driver to indicate the maximum supported
segment size in a nice an easy way, so that the driver doesn't
have to worry about DMA-layer imposed limitations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Christoph Hellwig 2018-12-13 16:17:03 +01:00 committed by Martin K. Petersen
parent 2a3d4eb8e2
commit 50c2e9107f
5 changed files with 15 additions and 9 deletions

View File

@ -214,12 +214,6 @@ static char const *cqe_desc[] = {
"CXN_KILLED_IMM_DATA_RCVD" "CXN_KILLED_IMM_DATA_RCVD"
}; };
static int beiscsi_slave_configure(struct scsi_device *sdev)
{
blk_queue_max_segment_size(sdev->request_queue, 65536);
return 0;
}
static int beiscsi_eh_abort(struct scsi_cmnd *sc) static int beiscsi_eh_abort(struct scsi_cmnd *sc)
{ {
struct iscsi_task *abrt_task = (struct iscsi_task *)sc->SCp.ptr; struct iscsi_task *abrt_task = (struct iscsi_task *)sc->SCp.ptr;
@ -393,7 +387,6 @@ static struct scsi_host_template beiscsi_sht = {
.proc_name = DRV_NAME, .proc_name = DRV_NAME,
.queuecommand = iscsi_queuecommand, .queuecommand = iscsi_queuecommand,
.change_queue_depth = scsi_change_queue_depth, .change_queue_depth = scsi_change_queue_depth,
.slave_configure = beiscsi_slave_configure,
.target_alloc = iscsi_target_alloc, .target_alloc = iscsi_target_alloc,
.eh_timed_out = iscsi_eh_cmd_timed_out, .eh_timed_out = iscsi_eh_cmd_timed_out,
.eh_abort_handler = beiscsi_eh_abort, .eh_abort_handler = beiscsi_eh_abort,
@ -404,6 +397,7 @@ static struct scsi_host_template beiscsi_sht = {
.can_queue = BE2_IO_DEPTH, .can_queue = BE2_IO_DEPTH,
.this_id = -1, .this_id = -1,
.max_sectors = BEISCSI_MAX_SECTORS, .max_sectors = BEISCSI_MAX_SECTORS,
.max_segment_size = 65536,
.cmd_per_lun = BEISCSI_CMD_PER_LUN, .cmd_per_lun = BEISCSI_CMD_PER_LUN,
.vendor_id = SCSI_NL_VID_TYPE_PCI | BE_VENDOR_ID, .vendor_id = SCSI_NL_VID_TYPE_PCI | BE_VENDOR_ID,
.track_queue_depth = 1, .track_queue_depth = 1,

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@ -464,6 +464,11 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
else else
shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS; shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS;
if (sht->max_segment_size)
shost->max_segment_size = sht->max_segment_size;
else
shost->max_segment_size = BLK_MAX_SEGMENT_SIZE;
/* /*
* assume a 4GB boundary, if not set * assume a 4GB boundary, if not set
*/ */

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@ -3973,7 +3973,6 @@ static int scsi_debug_slave_configure(struct scsi_device *sdp)
return 1; /* no resources, will be marked offline */ return 1; /* no resources, will be marked offline */
} }
sdp->hostdata = devip; sdp->hostdata = devip;
blk_queue_max_segment_size(sdp->request_queue, -1U);
if (sdebug_no_uld) if (sdebug_no_uld)
sdp->no_uld_attach = 1; sdp->no_uld_attach = 1;
config_cdb_len(sdp); config_cdb_len(sdp);
@ -5851,6 +5850,7 @@ static struct scsi_host_template sdebug_driver_template = {
.sg_tablesize = SG_MAX_SEGMENTS, .sg_tablesize = SG_MAX_SEGMENTS,
.cmd_per_lun = DEF_CMD_PER_LUN, .cmd_per_lun = DEF_CMD_PER_LUN,
.max_sectors = -1U, .max_sectors = -1U,
.max_segment_size = -1U,
.module = THIS_MODULE, .module = THIS_MODULE,
.track_queue_depth = 1, .track_queue_depth = 1,
}; };

View File

@ -2227,7 +2227,8 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q)
blk_queue_segment_boundary(q, shost->dma_boundary); blk_queue_segment_boundary(q, shost->dma_boundary);
dma_set_seg_boundary(dev, shost->dma_boundary); dma_set_seg_boundary(dev, shost->dma_boundary);
blk_queue_max_segment_size(q, dma_get_max_seg_size(dev)); blk_queue_max_segment_size(q,
min(shost->max_segment_size, dma_get_max_seg_size(dev)));
if (shost->use_clustering == DISABLE_CLUSTERING) if (shost->use_clustering == DISABLE_CLUSTERING)
q->limits.cluster = 0; q->limits.cluster = 0;

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@ -364,6 +364,11 @@ struct scsi_host_template {
*/ */
unsigned int max_sectors; unsigned int max_sectors;
/*
* Maximum size in bytes of a single segment.
*/
unsigned int max_segment_size;
/* /*
* DMA scatter gather segment boundary limit. A segment crossing this * DMA scatter gather segment boundary limit. A segment crossing this
* boundary will be split in two. * boundary will be split in two.
@ -603,6 +608,7 @@ struct Scsi_Host {
short unsigned int sg_tablesize; short unsigned int sg_tablesize;
short unsigned int sg_prot_tablesize; short unsigned int sg_prot_tablesize;
unsigned int max_sectors; unsigned int max_sectors;
unsigned int max_segment_size;
unsigned long dma_boundary; unsigned long dma_boundary;
/* /*
* In scsi-mq mode, the number of hardware queues supported by the LLD. * In scsi-mq mode, the number of hardware queues supported by the LLD.