[PATCH 2/4] scsi: megaraid_sas -- add module param fast_load

[PATCH 2/4] scsi: megaraid_sas -- add module param fast_load

[bo yang]

Driver will skip physical devices scan for the first time if the
fast_load is set.

Signed-off-by: Bo Yang <bo.yang@lsi.com>

---

drivers/scsi/megaraid/megaraid_sas.c |   64 +++++++++++++++++++------
 1 files changed, 50 insertions(+), 14 deletions(-)

diff -rupN linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.c
linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.c
--- linux-2.6.22_orig/drivers/scsi/megaraid/megaraid_sas.c 2007-06-30
03:36:39.000000000 -0400
+++ linux-2.6.22_new/drivers/scsi/megaraid/megaraid_sas.c 2007-06-30
03:59:27.000000000 -0400
@@ -46,6 +46,21 @@
 #include <scsi/scsi_host.h>
 #include "megaraid_sas.h"
 
+/*
+ * Modules parameters
+ */
+
+/*
+ * Fast driver load option, skip scanning for physical devices during
load.
+ * This would result in physical devices being skipped during driver
load
+ * time. These can be later added though, using /proc/scsi/scsi
+ */
+static unsigned int fast_load = 0;
+module_param_named(fast_load, fast_load, int, 0);
+MODULE_PARM_DESC(fast_load,
+ "megasas: Faster loading of the driver, skips physical devices! \
+  (default=0)");
+
 MODULE_LICENSE("GPL");
 MODULE_VERSION(MEGASAS_VERSION);
 MODULE_AUTHOR("megaraidlinux@lsi.com");
@@ -1094,6 +1109,40 @@ megasas_service_aen(struct megasas_insta
 	megasas_return_cmd(instance, cmd);
 }
 
+static struct megasas_instance *megasas_lookup_instance(u16 host_no)
+{
+	int i;
+
+	for (i = 0; i < megasas_mgmt_info.max_index; i++) {
+
+		if ((megasas_mgmt_info.instance[i]) &&
+		    (megasas_mgmt_info.instance[i]->host->host_no == host_no))
+			return megasas_mgmt_info.instance[i];
+	}
+
+	return NULL;
+}
+
+static int megasas_slave_alloc(struct scsi_device *sdev) {
+	struct megasas_instance *instance ;
+	int tmp_fastload = fast_load;
+	instance = megasas_lookup_instance(sdev->host->host_no);
+
+	if (tmp_fastload && sdev->channel < MEGASAS_MAX_PD_CHANNELS) {
+		if ((sdev->id == MEGASAS_MAX_DEV_PER_CHANNEL -1) &&
+			(sdev->channel == MEGASAS_MAX_PD_CHANNELS - 1)) {
+			/* If fast load option was set and scan for last device is
+			 * over, reset the fast_load flag so that during a possible
+			 * next scan, devices can be made available
+			 */
+			fast_load = 0;
+		}
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
 /*
  * Scsi host template for megaraid_sas driver
  */
@@ -1103,6 +1152,7 @@ static struct scsi_host_template megasas
 	.name = "LSI Logic SAS based MegaRAID driver",
 	.proc_name = "megaraid_sas",
 	.slave_configure = megasas_slave_configure,
+	.slave_alloc = megasas_slave_alloc,
 	.queuecommand = megasas_queue_command,
 	.eh_device_reset_handler = megasas_reset_device,
 	.eh_bus_reset_handler = megasas_reset_bus_host,
@@ -2969,20 +3019,6 @@ megasas_mgmt_fw_ioctl(struct megasas_ins
 	return error;
 }
 
-static struct megasas_instance *megasas_lookup_instance(u16 host_no)
-{
-	int i;
-
-	for (i = 0; i < megasas_mgmt_info.max_index; i++) {
-
-		if ((megasas_mgmt_info.instance[i]) &&
-      (megasas_mgmt_info.instance[i]->host->host_no == host_no))
-   return megasas_mgmt_info.instance[i];
- }
-
- return NULL;
-}
-
 static int megasas_mgmt_ioctl_fw(struct file *file, unsigned long arg)
 {
 	struct megasas_iocpacket __user *user_ioc =

Re: [PATCH 2/4] scsi: megaraid_sas -- add module param fast_load

[Andrew Morton]

On Sun, 01 Jul 2007 12:42:33 -0400
bo yang <bo.yang@lsi.com> wrote:

> Driver will skip physical devices scan for the first time if the
> fast_load is set.
> 

All your patches are wordwrapped and will need to be resent.

Also, there are multiple trivial errors in here, pretty much all of which
would have been detected had you run scripts/checkpatch.pl across the
diffs:

> + */
> +static unsigned int fast_load = 0;

Unneeded initialisation

> +static int megasas_slave_alloc(struct scsi_device *sdev) {

Missing newline

> +	struct megasas_instance *instance ;

unneeded space

> +	int tmp_fastload = fast_load;
> +	instance = megasas_lookup_instance(sdev->host->host_no);

Missing blank line.

> +	if (tmp_fastload && sdev->channel < MEGASAS_MAX_PD_CHANNELS) {
> +		if ((sdev->id == MEGASAS_MAX_DEV_PER_CHANNEL -1) &&
> +			(sdev->channel == MEGASAS_MAX_PD_CHANNELS - 1)) {
> +			/* If fast load option was set and scan for last device is
> +			 * over, reset the fast_load flag so that during a possible
> +			 * next scan, devices can be made available
> +			 */
> +			fast_load = 0;
> +		}
> +		return -ENXIO;
> +	}
> +
> +	return 0;
> +}
> +