Commit 9447b6ce authored by Martin K. Petersen's avatar Martin K. Petersen
Browse files

scsi: scsi_debug: Implement support for write protect 



Teach scsi_debug to honor SWP in the Control Mode Page and report the
resulting WP state in the Device-Specific Parameter field.

In check_device_access_params() verify that commands that will write
the medium are permitted to do so.

Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: default avatarDouglas Gilbert <dgilbert@interlog.com>
parent 9fa505ad

drivers/scsi/scsi_debug.c

+31 −45
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ static const char *sdebug_version_date = "20180128"; 
#define LBA_OUT_OF_RANGE 0x21

#define INVALID_FIELD_IN_CDB 0x24

#define INVALID_FIELD_IN_PARAM_LIST 0x26

#define WRITE_PROTECTED 0x27

#define UA_RESET_ASC 0x29

#define UA_CHANGED_ASC 0x2a

#define TARGET_CHANGED_ASC 0x3f
@@ -668,6 +669,7 @@ static bool sdebug_verbose; 
static bool have_dif_prot;

static bool write_since_sync;

static bool sdebug_statistics = DEF_STATISTICS;

static bool sdebug_wp;



static unsigned int sdebug_store_sectors;

static sector_t sdebug_capacity;	/* in sectors */
@@ -2143,9 +2145,11 @@ static int resp_mode_sense(struct scsi_cmnd *scp, 
	target_dev_id = ((devip->sdbg_host->shost->host_no + 1) * 2000) +

			(devip->target * 1000) - 3;

	/* for disks set DPOFUA bit and clear write protect (WP) bit */

	if (is_disk)

	if (is_disk) {

		dev_spec = 0x10;	/* =0x90 if WP=1 implies read-only */

	else

		if (sdebug_wp)

			dev_spec |= 0x80;

	} else

		dev_spec = 0x0;

	if (msense_6) {

		arr[2] = dev_spec;
@@ -2328,6 +2332,10 @@ static int resp_mode_select(struct scsi_cmnd *scp, 
		if (ctrl_m_pg[1] == arr[off + 1]) {

			memcpy(ctrl_m_pg + 2, arr + off + 2,

			       sizeof(ctrl_m_pg) - 2);

			if (ctrl_m_pg[4] & 0x8)

				sdebug_wp = true;

			else

				sdebug_wp = false;

			sdebug_dsense = !!(ctrl_m_pg[2] & 0x4);

			goto set_mode_changed_ua;

		}
@@ -2452,8 +2460,8 @@ static int resp_log_sense(struct scsi_cmnd *scp, 
		    min(len, SDEBUG_MAX_INQ_ARR_SZ));

}



static int check_device_access_params(struct scsi_cmnd *scp,

				      unsigned long long lba, unsigned int num)

static inline int check_device_access_params(struct scsi_cmnd *scp,

	unsigned long long lba, unsigned int num, bool write)

{

	if (lba + num > sdebug_capacity) {

		mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
@@ -2465,6 +2473,10 @@ static int check_device_access_params(struct scsi_cmnd *scp, 
		mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);

		return check_condition_result;

	}

	if (write && unlikely(sdebug_wp)) {

		mk_sense_buffer(scp, DATA_PROTECT, WRITE_PROTECTED, 0x2);

		return check_condition_result;

	}

	return 0;

}
@@ -2723,18 +2735,9 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) 
	} else

		sqcp = NULL;



	/* inline check_device_access_params() */

	if (unlikely(lba + num > sdebug_capacity)) {

		mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);

		return check_condition_result;

	}

	/* transfer length excessive (tie in to block limits VPD page) */

	if (unlikely(num > sdebug_store_sectors)) {

		/* needs work to find which cdb byte 'num' comes from */

		mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);

		return check_condition_result;

	}



	ret = check_device_access_params(scp, lba, num, false);

	if (ret)

		return ret;

	if (unlikely((SDEBUG_OPT_MEDIUM_ERR & sdebug_opts) &&

		     (lba <= (sdebug_medium_error_start + sdebug_medium_error_count - 1)) &&

		     ((lba + num) > sdebug_medium_error_start))) {
@@ -3026,19 +3029,9 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) 
			sdev_printk(KERN_ERR, scp->device, "Unprotected WR "

				    "to DIF device\n");

	}



	/* inline check_device_access_params() */

	if (unlikely(lba + num > sdebug_capacity)) {

		mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);

		return check_condition_result;

	}

	/* transfer length excessive (tie in to block limits VPD page) */

	if (unlikely(num > sdebug_store_sectors)) {

		/* needs work to find which cdb byte 'num' comes from */

		mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);

		return check_condition_result;

	}



	ret = check_device_access_params(scp, lba, num, true);

	if (ret)

		return ret;

	write_lock_irqsave(&atomic_rw, iflags);



	/* DIX + T10 DIF */
@@ -3177,7 +3170,7 @@ static int resp_write_scat(struct scsi_cmnd *scp, 
				my_name, __func__, k, lba, num, sg_off);

		if (num == 0)

			continue;

		ret = check_device_access_params(scp, lba, num);

		ret = check_device_access_params(scp, lba, num, true);

		if (ret)

			goto err_out_unlock;

		num_by = num * lb_size;
@@ -3261,7 +3254,7 @@ static int resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num, 
	int ret;

	u64 lba_off;



	ret = check_device_access_params(scp, lba, num);

	ret = check_device_access_params(scp, lba, num, true);

	if (ret)

		return ret;
@@ -3434,18 +3427,9 @@ static int resp_comp_write(struct scsi_cmnd *scp, 
	    (cmd[1] & 0xe0) == 0)

		sdev_printk(KERN_ERR, scp->device, "Unprotected WR "

			    "to DIF device\n");



	/* inline check_device_access_params() */

	if (lba + num > sdebug_capacity) {

		mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);

		return check_condition_result;

	}

	/* transfer length excessive (tie in to block limits VPD page) */

	if (num > sdebug_store_sectors) {

		/* needs work to find which cdb byte 'num' comes from */

		mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);

		return check_condition_result;

	}

	ret = check_device_access_params(scp, lba, num, false);

	if (ret)

		return ret;

	dnum = 2 * num;

	arr = kcalloc(lb_size, dnum, GFP_ATOMIC);

	if (NULL == arr) {
@@ -3528,7 +3512,7 @@ static int resp_unmap(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) 
		unsigned long long lba = get_unaligned_be64(&desc[i].lba);

		unsigned int num = get_unaligned_be32(&desc[i].blocks);



		ret = check_device_access_params(scp, lba, num);

		ret = check_device_access_params(scp, lba, num, true);

		if (ret)

			goto out;
@@ -3561,7 +3545,7 @@ static int resp_get_lba_status(struct scsi_cmnd *scp, 
	if (alloc_len < 24)

		return 0;



	ret = check_device_access_params(scp, lba, 1);

	ret = check_device_access_params(scp, lba, 1, false);

	if (ret)

		return ret;
@@ -4485,6 +4469,7 @@ module_param_named(virtual_gb, sdebug_virtual_gb, int, S_IRUGO | S_IWUSR); 
module_param_named(uuid_ctl, sdebug_uuid_ctl, int, S_IRUGO);

module_param_named(vpd_use_hostno, sdebug_vpd_use_hostno, int,

		   S_IRUGO | S_IWUSR);

module_param_named(wp, sdebug_wp, bool, S_IRUGO | S_IWUSR);

module_param_named(write_same_length, sdebug_write_same_length, int,

		   S_IRUGO | S_IWUSR);
@@ -4544,6 +4529,7 @@ MODULE_PARM_DESC(uuid_ctl, 
		 "1->use uuid for lu name, 0->don't, 2->all use same (def=0)");

MODULE_PARM_DESC(virtual_gb, "virtual gigabyte (GiB) size (def=0 -> use dev_size_mb)");

MODULE_PARM_DESC(vpd_use_hostno, "0 -> dev ids ignore hostno (def=1 -> unique dev ids)");

MODULE_PARM_DESC(wp, "Write Protect (def=0)");

MODULE_PARM_DESC(write_same_length, "Maximum blocks per WRITE SAME cmd (def=0xffff)");



#define SDEBUG_INFO_LEN 256

CRA Git | Maintained and supported by SUSTech CRA and CCSE