Commit 62275040 authored by Brian King's avatar Brian King Committed by James Bottomley
Browse files

[SCSI] ipr: Write caching state host attribute 



Adds a scsi_host sysfs attribute and module parm to enable/disable
the write cache on an ipr adapter.

Signed-off-by: default avatarBrian King <brking@us.ibm.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 692aebfc

drivers/scsi/ipr.c

+192 −9
Original line number Diff line number Diff line
@@ -91,6 +91,7 @@ static unsigned int ipr_max_speed = 1; 
static int ipr_testmode = 0;

static unsigned int ipr_fastfail = 0;

static unsigned int ipr_transop_timeout = IPR_OPERATIONAL_TIMEOUT;

static unsigned int ipr_enable_cache = 1;

static DEFINE_SPINLOCK(ipr_driver_lock);



/* This table describes the differences between DMA controller chips */
@@ -150,6 +151,8 @@ module_param_named(fastfail, ipr_fastfail, int, 0); 
MODULE_PARM_DESC(fastfail, "Reduce timeouts and retries");

module_param_named(transop_timeout, ipr_transop_timeout, int, 0);

MODULE_PARM_DESC(transop_timeout, "Time in seconds to wait for adapter to come operational (default: 300)");

module_param_named(enable_cache, ipr_enable_cache, int, 0);

MODULE_PARM_DESC(enable_cache, "Enable adapter's non-volatile write cache (default: 1)");

MODULE_LICENSE("GPL");

MODULE_VERSION(IPR_DRIVER_VERSION);
@@ -1937,6 +1940,103 @@ static struct bin_attribute ipr_trace_attr = { 
};

#endif



static const struct {

	enum ipr_cache_state state;

	char *name;

} cache_state [] = {

	{ CACHE_NONE, "none" },

	{ CACHE_DISABLED, "disabled" },

	{ CACHE_ENABLED, "enabled" }

};



/**

 * ipr_show_write_caching - Show the write caching attribute

 * @class_dev:	class device struct

 * @buf:		buffer

 *

 * Return value:

 *	number of bytes printed to buffer

 **/

static ssize_t ipr_show_write_caching(struct class_device *class_dev, char *buf)

{

	struct Scsi_Host *shost = class_to_shost(class_dev);

	struct ipr_ioa_cfg *ioa_cfg = (struct ipr_ioa_cfg *)shost->hostdata;

	unsigned long lock_flags = 0;

	int i, len = 0;



	spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);

	for (i = 0; i < ARRAY_SIZE(cache_state); i++) {

		if (cache_state[i].state == ioa_cfg->cache_state) {

			len = snprintf(buf, PAGE_SIZE, "%s\n", cache_state[i].name);

			break;

		}

	}

	spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);

	return len;

}





/**

 * ipr_store_write_caching - Enable/disable adapter write cache

 * @class_dev:	class_device struct

 * @buf:		buffer

 * @count:		buffer size

 *

 * This function will enable/disable adapter write cache.

 *

 * Return value:

 * 	count on success / other on failure

 **/

static ssize_t ipr_store_write_caching(struct class_device *class_dev,

					const char *buf, size_t count)

{

	struct Scsi_Host *shost = class_to_shost(class_dev);

	struct ipr_ioa_cfg *ioa_cfg = (struct ipr_ioa_cfg *)shost->hostdata;

	unsigned long lock_flags = 0;

	enum ipr_cache_state new_state = CACHE_INVALID;

	int i;



	if (!capable(CAP_SYS_ADMIN))

		return -EACCES;

	if (ioa_cfg->cache_state == CACHE_NONE)

		return -EINVAL;



	for (i = 0; i < ARRAY_SIZE(cache_state); i++) {

		if (!strncmp(cache_state[i].name, buf, strlen(cache_state[i].name))) {

			new_state = cache_state[i].state;

			break;

		}

	}



	if (new_state != CACHE_DISABLED && new_state != CACHE_ENABLED)

		return -EINVAL;



	spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);

	if (ioa_cfg->cache_state == new_state) {

		spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);

		return count;

	}



	ioa_cfg->cache_state = new_state;

	dev_info(&ioa_cfg->pdev->dev, "%s adapter write cache.\n",

		 new_state == CACHE_ENABLED ? "Enabling" : "Disabling");

	if (!ioa_cfg->in_reset_reload)

		ipr_initiate_ioa_reset(ioa_cfg, IPR_SHUTDOWN_NORMAL);

	spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);

	wait_event(ioa_cfg->reset_wait_q, !ioa_cfg->in_reset_reload);



	return count;

}



static struct class_device_attribute ipr_ioa_cache_attr = {

	.attr = {

		.name =		"write_cache",

		.mode =		S_IRUGO | S_IWUSR,

	},

	.show = ipr_show_write_caching,

	.store = ipr_store_write_caching

};



/**

 * ipr_show_fw_version - Show the firmware version

 * @class_dev:	class device struct
@@ -2406,6 +2506,7 @@ static struct class_device_attribute *ipr_ioa_attrs[] = { 
	&ipr_diagnostics_attr,

	&ipr_ioa_reset_attr,

	&ipr_update_fw_attr,

	&ipr_ioa_cache_attr,

	NULL,

};
@@ -4147,6 +4248,36 @@ static int ipr_set_supported_devs(struct ipr_cmnd *ipr_cmd) 
	return IPR_RC_JOB_CONTINUE;

}



/**

 * ipr_setup_write_cache - Disable write cache if needed

 * @ipr_cmd:	ipr command struct

 *

 * This function sets up adapters write cache to desired setting

 *

 * Return value:

 * 	IPR_RC_JOB_CONTINUE / IPR_RC_JOB_RETURN

 **/

static int ipr_setup_write_cache(struct ipr_cmnd *ipr_cmd)

{

	struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;



	ipr_cmd->job_step = ipr_set_supported_devs;

	ipr_cmd->u.res = list_entry(ioa_cfg->used_res_q.next,

				    struct ipr_resource_entry, queue);



	if (ioa_cfg->cache_state != CACHE_DISABLED)

		return IPR_RC_JOB_CONTINUE;



	ipr_cmd->ioarcb.res_handle = cpu_to_be32(IPR_IOA_RES_HANDLE);

	ipr_cmd->ioarcb.cmd_pkt.request_type = IPR_RQTYPE_IOACMD;

	ipr_cmd->ioarcb.cmd_pkt.cdb[0] = IPR_IOA_SHUTDOWN;

	ipr_cmd->ioarcb.cmd_pkt.cdb[1] = IPR_SHUTDOWN_PREPARE_FOR_NORMAL;



	ipr_do_req(ipr_cmd, ipr_reset_ioa_job, ipr_timeout, IPR_INTERNAL_TIMEOUT);



	return IPR_RC_JOB_RETURN;

}



/**

 * ipr_get_mode_page - Locate specified mode page

 * @mode_pages:	mode page buffer
@@ -4358,10 +4489,7 @@ static int ipr_ioafp_mode_select_page28(struct ipr_cmnd *ipr_cmd) 
			      ioa_cfg->vpd_cbs_dma + offsetof(struct ipr_misc_cbs, mode_pages),

			      length);



	ipr_cmd->job_step = ipr_set_supported_devs;

	ipr_cmd->u.res = list_entry(ioa_cfg->used_res_q.next,

				    struct ipr_resource_entry, queue);



	ipr_cmd->job_step = ipr_setup_write_cache;

	ipr_do_req(ipr_cmd, ipr_reset_ioa_job, ipr_timeout, IPR_INTERNAL_TIMEOUT);



	LEAVE;
@@ -4580,6 +4708,27 @@ static void ipr_ioafp_inquiry(struct ipr_cmnd *ipr_cmd, u8 flags, u8 page, 
	LEAVE;

}



/**

 * ipr_inquiry_page_supported - Is the given inquiry page supported

 * @page0:		inquiry page 0 buffer

 * @page:		page code.

 *

 * This function determines if the specified inquiry page is supported.

 *

 * Return value:

 *	1 if page is supported / 0 if not

 **/

static int ipr_inquiry_page_supported(struct ipr_inquiry_page0 *page0, u8 page)

{

	int i;



	for (i = 0; i < min_t(u8, page0->len, IPR_INQUIRY_PAGE0_ENTRIES); i++)

		if (page0->page[i] == page)

			return 1;



	return 0;

}



/**

 * ipr_ioafp_page3_inquiry - Send a Page 3 Inquiry to the adapter.

 * @ipr_cmd:	ipr command struct
@@ -4591,6 +4740,36 @@ static void ipr_ioafp_inquiry(struct ipr_cmnd *ipr_cmd, u8 flags, u8 page, 
 * 	IPR_RC_JOB_CONTINUE / IPR_RC_JOB_RETURN

 **/

static int ipr_ioafp_page3_inquiry(struct ipr_cmnd *ipr_cmd)

{

	struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;

	struct ipr_inquiry_page0 *page0 = &ioa_cfg->vpd_cbs->page0_data;



	ENTER;



	if (!ipr_inquiry_page_supported(page0, 1))

		ioa_cfg->cache_state = CACHE_NONE;



	ipr_cmd->job_step = ipr_ioafp_query_ioa_cfg;



	ipr_ioafp_inquiry(ipr_cmd, 1, 3,

			  ioa_cfg->vpd_cbs_dma + offsetof(struct ipr_misc_cbs, page3_data),

			  sizeof(struct ipr_inquiry_page3));



	LEAVE;

	return IPR_RC_JOB_RETURN;

}



/**

 * ipr_ioafp_page0_inquiry - Send a Page 0 Inquiry to the adapter.

 * @ipr_cmd:	ipr command struct

 *

 * This function sends a Page 0 inquiry to the adapter

 * to retrieve supported inquiry pages.

 *

 * Return value:

 * 	IPR_RC_JOB_CONTINUE / IPR_RC_JOB_RETURN

 **/

static int ipr_ioafp_page0_inquiry(struct ipr_cmnd *ipr_cmd)

{

	struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;

	char type[5];
@@ -4602,11 +4781,11 @@ static int ipr_ioafp_page3_inquiry(struct ipr_cmnd *ipr_cmd) 
	type[4] = '\0';

	ioa_cfg->type = simple_strtoul((char *)type, NULL, 16);



	ipr_cmd->job_step = ipr_ioafp_query_ioa_cfg;

	ipr_cmd->job_step = ipr_ioafp_page3_inquiry;



	ipr_ioafp_inquiry(ipr_cmd, 1, 3,

			  ioa_cfg->vpd_cbs_dma + offsetof(struct ipr_misc_cbs, page3_data),

			  sizeof(struct ipr_inquiry_page3));

	ipr_ioafp_inquiry(ipr_cmd, 1, 0,

			  ioa_cfg->vpd_cbs_dma + offsetof(struct ipr_misc_cbs, page0_data),

			  sizeof(struct ipr_inquiry_page0));



	LEAVE;

	return IPR_RC_JOB_RETURN;
@@ -4626,7 +4805,7 @@ static int ipr_ioafp_std_inquiry(struct ipr_cmnd *ipr_cmd) 
	struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;



	ENTER;

	ipr_cmd->job_step = ipr_ioafp_page3_inquiry;

	ipr_cmd->job_step = ipr_ioafp_page0_inquiry;



	ipr_ioafp_inquiry(ipr_cmd, 0, 0,

			  ioa_cfg->vpd_cbs_dma + offsetof(struct ipr_misc_cbs, ioa_vpd),
@@ -5629,6 +5808,10 @@ static void __devinit ipr_init_ioa_cfg(struct ipr_ioa_cfg *ioa_cfg, 
	INIT_WORK(&ioa_cfg->work_q, ipr_worker_thread, ioa_cfg);

	init_waitqueue_head(&ioa_cfg->reset_wait_q);

	ioa_cfg->sdt_state = INACTIVE;

	if (ipr_enable_cache)

		ioa_cfg->cache_state = CACHE_ENABLED;

	else

		ioa_cfg->cache_state = CACHE_DISABLED;



	ipr_initialize_bus_attr(ioa_cfg);

drivers/scsi/ipr.h

+18 −0
Original line number Diff line number Diff line
@@ -541,6 +541,15 @@ struct ipr_inquiry_page3 { 
	u8 patch_number[4];

}__attribute__((packed));



#define IPR_INQUIRY_PAGE0_ENTRIES 20

struct ipr_inquiry_page0 {

	u8 peri_qual_dev_type;

	u8 page_code;

	u8 reserved1;

	u8 len;

	u8 page[IPR_INQUIRY_PAGE0_ENTRIES];

}__attribute__((packed));



struct ipr_hostrcb_device_data_entry {

	struct ipr_vpd vpd;

	struct ipr_res_addr dev_res_addr;
@@ -731,6 +740,7 @@ struct ipr_resource_table { 


struct ipr_misc_cbs {

	struct ipr_ioa_vpd ioa_vpd;

	struct ipr_inquiry_page0 page0_data;

	struct ipr_inquiry_page3 page3_data;

	struct ipr_mode_pages mode_pages;

	struct ipr_supported_device supp_dev;
@@ -813,6 +823,13 @@ enum ipr_sdt_state { 
	DUMP_OBTAINED

};



enum ipr_cache_state {

	CACHE_NONE,

	CACHE_DISABLED,

	CACHE_ENABLED,

	CACHE_INVALID

};



/* Per-controller data */

struct ipr_ioa_cfg {

	char eye_catcher[8];
@@ -829,6 +846,7 @@ struct ipr_ioa_cfg { 
	u8 allow_cmds:1;

	u8 allow_ml_add_del:1;



	enum ipr_cache_state cache_state;

	u16 type; /* CCIN of the card */



	u8 log_level;