[PATCH 5/13] scsi: arcmsr: add driver option host_can_queue to set host->can_queue value by user. It's value expands up to 1024

[Ching Huang]

From: Ching Huang <ching2...@areca.com.tw>

add driver option host_can_queue to set host->can_queue value by user. It's 
value expands up to 1024

Signed-off-by: Ching Huang <ching2...@areca.com.tw>
---

diff -uprN a/drivers/scsi/arcmsr/arcmsr.h b/drivers/scsi/arcmsr/arcmsr.h
--- a/drivers/scsi/arcmsr/arcmsr.h      2017-08-04 17:07:52.000000000 +0800
+++ b/drivers/scsi/arcmsr/arcmsr.h      2017-08-04 17:40:54.000000000 +0800
@@ -49,9 +49,11 @@ struct device_attribute;
        #define ARCMSR_MAX_FREECCB_NUM  160
 #define ARCMSR_MAX_OUTSTANDING_CMD     155
 #else
-       #define ARCMSR_MAX_FREECCB_NUM  320
-#define ARCMSR_MAX_OUTSTANDING_CMD     255
+       #define ARCMSR_MAX_FREECCB_NUM  1024
+#define ARCMSR_MAX_OUTSTANDING_CMD     1024
 #endif
+#define ARCMSR_DEFAULT_OUTSTANDING_CMD 128
+#define ARCMSR_MIN_OUTSTANDING_CMD     32
 #define ARCMSR_DRIVER_VERSION          "v1.30.00.22-20151126"
 #define ARCMSR_SCSI_INITIATOR_ID                                               
255
 #define ARCMSR_MAX_XFER_SECTORS                                                
        512
diff -uprN a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
--- a/drivers/scsi/arcmsr/arcmsr_hba.c  2017-11-08 18:50:28.000000000 +0800
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c  2017-11-08 18:51:20.000000000 +0800
@@ -75,6 +75,10 @@ MODULE_DESCRIPTION("Areca ARC11xx/12xx/1
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_VERSION(ARCMSR_DRIVER_VERSION);
 
+static int host_can_queue = ARCMSR_DEFAULT_OUTSTANDING_CMD;
+module_param(host_can_queue, int, S_IRUGO);
+MODULE_PARM_DESC(host_can_queue, " adapter queue depth(32 ~ 1024), default is 
128");
+
 #define        ARCMSR_SLEEPTIME        10
 #define        ARCMSR_RETRYCOUNT       12
 
@@ -133,7 +137,7 @@ static struct scsi_host_template arcmsr_
        .eh_bus_reset_handler   = arcmsr_bus_reset,
        .bios_param             = arcmsr_bios_param,
        .change_queue_depth     = arcmsr_adjust_disk_queue_depth,
-       .can_queue              = ARCMSR_MAX_OUTSTANDING_CMD,
+       .can_queue              = ARCMSR_DEFAULT_OUTSTANDING_CMD,
        .this_id                        = ARCMSR_SCSI_INITIATOR_ID,
        .sg_tablesize                   = ARCMSR_DEFAULT_SG_ENTRIES, 
        .max_sectors                    = ARCMSR_MAX_XFER_SECTORS_C, 
@@ -877,7 +881,9 @@ static int arcmsr_probe(struct pci_dev *
        host->max_lun = ARCMSR_MAX_TARGETLUN;
        host->max_id = ARCMSR_MAX_TARGETID;             /*16:8*/
        host->max_cmd_len = 16;                         /*this is issue of 
64bit LBA ,over 2T byte*/
-       host->can_queue = ARCMSR_MAX_OUTSTANDING_CMD;
+       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;          
        host->this_id = ARCMSR_SCSI_INITIATOR_ID;
        host->unique_id = (bus << 8) | dev_fun;
@@ -3238,11 +3244,11 @@ static bool arcmsr_get_firmware_spec(str
        default:
                break;
        }
-       if (acb->firm_numbers_queue > ARCMSR_MAX_OUTSTANDING_CMD)
-               acb->maxOutstanding = ARCMSR_MAX_OUTSTANDING_CMD;
+       acb->maxOutstanding = acb->firm_numbers_queue - 1;
+       if (acb->host->can_queue >= acb->firm_numbers_queue)
+               acb->host->can_queue = acb->maxOutstanding;
        else
-               acb->maxOutstanding = acb->firm_numbers_queue - 1;
-       acb->host->can_queue = acb->maxOutstanding;
+               acb->maxOutstanding = acb->host->can_queue;
        acb->maxFreeCCB = acb->host->can_queue;
        if (acb->maxFreeCCB < ARCMSR_MAX_FREECCB_NUM)
                acb->maxFreeCCB += 64;