[PATCH 8/17] scsi: arcmsr: add driver option cmd_per_lun to set host->cmd_per_lun value by user

From: Ching Huang
Date: Tue Dec 05 2017 - 04:55:41 EST


From: Ching Huang <ching2048@xxxxxxxxxxxx>

add driver option cmd_per_lun to set host->cmd_per_lun value by user

Signed-off-by: Ching Huang <ching2048@xxxxxxxxxxxx>
---

diff -uprN a/drivers/scsi/arcmsr/arcmsr.h b/drivers/scsi/arcmsr/arcmsr.h
--- a/drivers/scsi/arcmsr/arcmsr.h 2017-12-05 15:26:06.000000000 +0800
+++ b/drivers/scsi/arcmsr/arcmsr.h 2017-12-05 15:26:32.000000000 +0800
@@ -56,7 +56,9 @@ struct device_attribute;
#define ARCMSR_MAX_XFER_SECTORS_C 304
#define ARCMSR_MAX_TARGETID 17
#define ARCMSR_MAX_TARGETLUN 8
-#define ARCMSR_MAX_CMD_PERLUN ARCMSR_MAX_OUTSTANDING_CMD
+#define ARCMSR_MAX_CMD_PERLUN 128
+#define ARCMSR_DEFAULT_CMD_PERLUN 32
+#define ARCMSR_MIN_CMD_PERLUN 1
#define ARCMSR_MAX_QBUFFER 4096
#define ARCMSR_DEFAULT_SG_ENTRIES 38
#define ARCMSR_MAX_HBB_POSTQUEUE 264
diff -uprN a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
--- a/drivers/scsi/arcmsr/arcmsr_hba.c 2017-12-05 11:46:30.000000000 +0800
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c 2017-12-05 11:46:18.000000000 +0800
@@ -79,6 +79,10 @@ static int host_can_queue = ARCMSR_DEFAU
module_param(host_can_queue, int, S_IRUGO);
MODULE_PARM_DESC(host_can_queue, " adapter queue depth(32 ~ 1024), default is 128");

+static int cmd_per_lun = ARCMSR_DEFAULT_CMD_PERLUN;
+module_param(cmd_per_lun, int, S_IRUGO);
+MODULE_PARM_DESC(cmd_per_lun, " device queue depth(1 ~ 128), default is 32");
+
#define ARCMSR_SLEEPTIME 10
#define ARCMSR_RETRYCOUNT 12

@@ -141,7 +145,7 @@ static struct scsi_host_template arcmsr_
.this_id = ARCMSR_SCSI_INITIATOR_ID,
.sg_tablesize = ARCMSR_DEFAULT_SG_ENTRIES,
.max_sectors = ARCMSR_MAX_XFER_SECTORS_C,
- .cmd_per_lun = ARCMSR_MAX_CMD_PERLUN,
+ .cmd_per_lun = ARCMSR_DEFAULT_CMD_PERLUN,
.use_clustering = ENABLE_CLUSTERING,
.shost_attrs = arcmsr_host_attrs,
.no_write_same = 1,
@@ -884,7 +888,9 @@ static int arcmsr_probe(struct pci_dev *
if ((host_can_queue < ARCMSR_MIN_OUTSTANDING_CMD) || (host_can_queue > ARCMSR_MAX_OUTSTANDING_CMD))
host_can_queue = ARCMSR_DEFAULT_OUTSTANDING_CMD;
host->can_queue = host_can_queue; /* max simultaneous cmds */
- host->cmd_per_lun = ARCMSR_MAX_CMD_PERLUN;
+ if ((cmd_per_lun < ARCMSR_MIN_CMD_PERLUN) || (cmd_per_lun > ARCMSR_MAX_CMD_PERLUN))
+ cmd_per_lun = ARCMSR_DEFAULT_CMD_PERLUN;
+ host->cmd_per_lun = cmd_per_lun;
host->this_id = ARCMSR_SCSI_INITIATOR_ID;
host->unique_id = (bus << 8) | dev_fun;
pci_set_drvdata(pdev, host);