Commit 64e14ece authored by Damien Le Moal's avatar Damien Le Moal Committed by Martin K. Petersen
Browse files

scsi: scsi_debug: Implement ZBC host-aware emulation 

Implement ZBC host-aware device model emulation. The main changes from the
host-managed emulation are the device type (TYPE_DISK is used), relaxation
of access checks for read and write operations and different handling of a
sequential write preferred zone write pointer as mandated by the ZBC r05
specifications.

To facilitate the implementation and avoid a lot of "if" statement, the
zmodel field is added to the device information and the z_type field to the
zone state data structure.

Link: https://lore.kernel.org/r/20200422104221.378203-8-damien.lemoal@wdc.com


Tested-by: default avatarDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: default avatarDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 98e0a689

drivers/scsi/scsi_debug.c

+103 −45
Original line number Diff line number Diff line
@@ -262,6 +262,13 @@ static const char *sdebug_version_date = "20200421"; 


#define SDEB_XA_NOT_IN_USE XA_MARK_1



/* Zone types (zbcr05 table 25) */

enum sdebug_z_type {

	ZBC_ZONE_TYPE_CNV	= 0x1,

	ZBC_ZONE_TYPE_SWR	= 0x2,

	ZBC_ZONE_TYPE_SWP	= 0x3,

};



/* enumeration names taken from table 26, zbcr05 */

enum sdebug_z_cond {

	ZBC_NOT_WRITE_POINTER	= 0x0,
@@ -275,7 +282,9 @@ enum sdebug_z_cond { 
};



struct sdeb_zone_state {	/* ZBC: per zone state */

	enum sdebug_z_type z_type;

	enum sdebug_z_cond z_cond;

	bool z_non_seq_resource;

	unsigned int z_size;

	sector_t z_start;

	sector_t z_wp;
@@ -294,6 +303,7 @@ struct sdebug_dev_info { 
	bool used;



	/* For ZBC devices */

	enum blk_zoned_model zmodel;

	unsigned int zsize;

	unsigned int zsize_shift;

	unsigned int nr_zones;
@@ -822,7 +832,7 @@ static int dix_reads; 
static int dif_errors;



/* ZBC global data */

static bool sdeb_zbc_in_use;		/* true when ptype=TYPE_ZBC [0x14] */

static bool sdeb_zbc_in_use;	/* true for host-aware and host-managed disks */

static int sdeb_zbc_zone_size_mb;

static int sdeb_zbc_max_open = DEF_ZBC_MAX_OPEN_ZONES;

static int sdeb_zbc_nr_conv = DEF_ZBC_NR_CONV_ZONES;
@@ -1500,13 +1510,15 @@ static int inquiry_vpd_b0(unsigned char *arr) 
}



/* Block device characteristics VPD page (SBC-3) */

static int inquiry_vpd_b1(unsigned char *arr)

static int inquiry_vpd_b1(struct sdebug_dev_info *devip, unsigned char *arr)

{

	memset(arr, 0, 0x3c);

	arr[0] = 0;

	arr[1] = 1;	/* non rotating medium (e.g. solid state) */

	arr[2] = 0;

	arr[3] = 5;	/* less than 1.8" */

	if (devip->zmodel == BLK_ZONED_HA)

		arr[4] = 1 << 4;	/* zoned field = 01b */



	return 0x3c;

}
@@ -1543,7 +1555,7 @@ static int inquiry_vpd_b6(struct sdebug_dev_info *devip, unsigned char *arr) 
	 */

	put_unaligned_be32(0xffffffff, &arr[4]);

	put_unaligned_be32(0xffffffff, &arr[8]);

	if (devip->max_open)

	if (sdeb_zbc_model == BLK_ZONED_HM && devip->max_open)

		put_unaligned_be32(devip->max_open, &arr[12]);

	else

		put_unaligned_be32(0xffffffff, &arr[12]);
@@ -1566,7 +1578,7 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) 
	if (! arr)

		return DID_REQUEUE << 16;

	is_disk = (sdebug_ptype == TYPE_DISK);

	is_zbc = (sdebug_ptype == TYPE_ZBC);

	is_zbc = (devip->zmodel != BLK_ZONED_NONE);

	is_disk_zbc = (is_disk || is_zbc);

	have_wlun = scsi_is_wlun(scp->device->lun);

	if (have_wlun)
@@ -1611,7 +1623,7 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) 
				arr[n++] = 0xb1;  /* Block characteristics */

				if (is_disk)

					arr[n++] = 0xb2;  /* LB Provisioning */

				else if (is_zbc)

				if (is_zbc)

					arr[n++] = 0xb6;  /* ZB dev. char. */

			}

			arr[3] = n - 4;	  /* number of supported VPD pages */
@@ -1660,7 +1672,7 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip) 
			arr[3] = inquiry_vpd_b0(&arr[4]);

		} else if (is_disk_zbc && 0xb1 == cmd[2]) { /* Block char. */

			arr[1] = cmd[2];        /*sanity */

			arr[3] = inquiry_vpd_b1(&arr[4]);

			arr[3] = inquiry_vpd_b1(devip, &arr[4]);

		} else if (is_disk && 0xb2 == cmd[2]) { /* LB Prov. */

			arr[1] = cmd[2];        /*sanity */

			arr[3] = inquiry_vpd_b2(&arr[4]);
@@ -2305,7 +2317,7 @@ static int resp_mode_sense(struct scsi_cmnd *scp, 
	msense_6 = (MODE_SENSE == cmd[0]);

	llbaa = msense_6 ? false : !!(cmd[1] & 0x10);

	is_disk = (sdebug_ptype == TYPE_DISK);

	is_zbc = (sdebug_ptype == TYPE_ZBC);

	is_zbc = (devip->zmodel != BLK_ZONED_NONE);

	if ((is_disk || is_zbc) && !dbd)

		bd_len = llbaa ? 16 : 8;

	else
@@ -2656,7 +2668,7 @@ static struct sdeb_zone_state *zbc_zone(struct sdebug_dev_info *devip, 


static inline bool zbc_zone_is_conv(struct sdeb_zone_state *zsp)

{

	return zsp->z_cond == ZBC_NOT_WRITE_POINTER;

	return zsp->z_type == ZBC_ZONE_TYPE_CNV;

}



static void zbc_close_zone(struct sdebug_dev_info *devip,
@@ -2732,13 +2744,42 @@ static void zbc_inc_wp(struct sdebug_dev_info *devip, 
		       unsigned long long lba, unsigned int num)

{

	struct sdeb_zone_state *zsp = zbc_zone(devip, lba);

	unsigned long long n, end, zend = zsp->z_start + zsp->z_size;



	if (zbc_zone_is_conv(zsp))

		return;



	if (zsp->z_type == ZBC_ZONE_TYPE_SWR) {

		zsp->z_wp += num;

	if (zsp->z_wp >= zsp->z_start + zsp->z_size)

		if (zsp->z_wp >= zend)

			zsp->z_cond = ZC5_FULL;

		return;

	}



	while (num) {

		if (lba != zsp->z_wp)

			zsp->z_non_seq_resource = true;



		end = lba + num;

		if (end >= zend) {

			n = zend - lba;

			zsp->z_wp = zend;

		} else if (end > zsp->z_wp) {

			n = num;

			zsp->z_wp = end;

		} else {

			n = num;

		}

		if (zsp->z_wp >= zend)

			zsp->z_cond = ZC5_FULL;



		num -= n;

		lba += n;

		if (num) {

			zsp++;

			zend = zsp->z_start + zsp->z_size;

		}

	}

}



static int check_zbc_access_params(struct scsi_cmnd *scp,
@@ -2750,7 +2791,9 @@ static int check_zbc_access_params(struct scsi_cmnd *scp, 
	struct sdeb_zone_state *zsp_end = zbc_zone(devip, lba + num - 1);



	if (!write) {

		/* Reads cannot cross zone types boundaries */

		if (devip->zmodel == BLK_ZONED_HA)

			return 0;

		/* For host-managed, reads cannot cross zone types boundaries */

		if (zsp_end != zsp &&

		    zbc_zone_is_conv(zsp) &&

		    !zbc_zone_is_conv(zsp_end)) {
@@ -2773,6 +2816,7 @@ static int check_zbc_access_params(struct scsi_cmnd *scp, 
		return 0;

	}



	if (zsp->z_type == ZBC_ZONE_TYPE_SWR) {

		/* Writes cannot cross sequential zone boundaries */

		if (zsp_end != zsp) {

			mk_sense_buffer(scp, ILLEGAL_REQUEST,
@@ -2793,6 +2837,7 @@ static int check_zbc_access_params(struct scsi_cmnd *scp, 
					UNALIGNED_WRITE_ASCQ);

			return check_condition_result;

		}

	}



	/* Handle implicit open of closed and empty zones */

	if (zsp->z_cond == ZC1_EMPTY || zsp->z_cond == ZC4_CLOSED) {
@@ -4312,13 +4357,16 @@ static int resp_report_zones(struct scsi_cmnd *scp, 
		case 0x06:

		case 0x07:

		case 0x10:

		case 0x11:

			/*

			 * Read-only, offline, reset WP recommended and

			 * non-seq-resource-used are not emulated: no zones

			 * to report;

			 * Read-only, offline, reset WP recommended are

			 * not emulated: no zones to report;

			 */

			continue;

		case 0x11:

			/* non-seq-resource set */

			if (!zsp->z_non_seq_resource)

				continue;

			break;

		case 0x3f:

			/* Not write pointer (conventional) zones */

			if (!zbc_zone_is_conv(zsp))
@@ -4333,11 +4381,10 @@ static int resp_report_zones(struct scsi_cmnd *scp, 


		if (nrz < rep_max_zones) {

			/* Fill zone descriptor */

			if (zbc_zone_is_conv(zsp))

				desc[0] = 0x1;

			else

				desc[0] = 0x2;

			desc[0] = zsp->z_type;

			desc[1] = zsp->z_cond << 4;

			if (zsp->z_non_seq_resource)

				desc[1] |= 1 << 1;

			put_unaligned_be64((u64)zsp->z_size, desc + 8);

			put_unaligned_be64((u64)zsp->z_start, desc + 16);

			put_unaligned_be64((u64)zsp->z_wp, desc + 24);
@@ -4591,6 +4638,7 @@ static void zbc_rwp_zone(struct sdebug_dev_info *devip, 
	if (zsp->z_cond == ZC4_CLOSED)

		devip->nr_closed--;



	zsp->z_non_seq_resource = false;

	zsp->z_wp = zsp->z_start;

	zsp->z_cond = ZC1_EMPTY;

}
@@ -4796,11 +4844,13 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip) 
	}

	devip->nr_conv_zones = sdeb_zbc_nr_conv;



	/* zbc_max_open_zones can be 0, meaning "not reported" (no limit) */

	if (devip->zmodel == BLK_ZONED_HM) {

		/* zbc_max_open_zones can be 0, meaning "not reported" */

		if (sdeb_zbc_max_open >= devip->nr_zones - 1)

			devip->max_open = (devip->nr_zones - 1) / 2;

		else

			devip->max_open = sdeb_zbc_max_open;

	}



	devip->zstate = kcalloc(devip->nr_zones,

				sizeof(struct sdeb_zone_state), GFP_KERNEL);
@@ -4813,9 +4863,14 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip) 
		zsp->z_start = zstart;



		if (i < devip->nr_conv_zones) {

			zsp->z_type = ZBC_ZONE_TYPE_CNV;

			zsp->z_cond = ZBC_NOT_WRITE_POINTER;

			zsp->z_wp = (sector_t)-1;

		} else {

			if (devip->zmodel == BLK_ZONED_HM)

				zsp->z_type = ZBC_ZONE_TYPE_SWR;

			else

				zsp->z_type = ZBC_ZONE_TYPE_SWP;

			zsp->z_cond = ZC1_EMPTY;

			zsp->z_wp = zsp->z_start;

		}
@@ -4851,10 +4906,13 @@ static struct sdebug_dev_info *sdebug_device_create( 
		}

		devip->sdbg_host = sdbg_host;

		if (sdeb_zbc_in_use) {

			devip->zmodel = sdeb_zbc_model;

			if (sdebug_device_create_zones(devip)) {

				kfree(devip);

				return NULL;

			}

		} else {

			devip->zmodel = BLK_ZONED_NONE;

		}

		devip->sdbg_host = sdbg_host;

		list_add_tail(&devip->dev_list, &sdbg_host->dev_info_list);
@@ -6564,12 +6622,12 @@ static int __init scsi_debug_init(void) 
		sdeb_zbc_model = k;

		switch (sdeb_zbc_model) {

		case BLK_ZONED_NONE:

		case BLK_ZONED_HA:

			sdebug_ptype = TYPE_DISK;

			break;

		case BLK_ZONED_HM:

			sdebug_ptype = TYPE_ZBC;

			break;

		case BLK_ZONED_HA:

		default:

			pr_err("Invalid ZBC model\n");

			return -EINVAL;

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