1 files changed, 227 insertions, 70 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index d03d66f114..acf0592d63 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -43,6 +43,7 @@
 #include <linux/prefetch.h>
 #include <linux/debugfs.h>
 #include <linux/async.h>
+#include <linux/cleanup.h>
 
 #include <net/checksum.h>
 
@@ -532,6 +533,8 @@ static int resp_write_scat(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_start_stop(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_readcap16(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_get_lba_status(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_get_stream_status(struct scsi_cmnd *scp,
+				  struct sdebug_dev_info *devip);
 static int resp_report_tgtpgs(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_unmap(struct scsi_cmnd *, struct sdebug_dev_info *);
 static int resp_rsup_opcodes(struct scsi_cmnd *, struct sdebug_dev_info *);
@@ -606,6 +609,9 @@ static const struct opcode_info_t sa_in_16_iarr[] = {
 	{0, 0x9e, 0x12, F_SA_LOW | F_D_IN, resp_get_lba_status, NULL,
 	    {16,  0x12, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
 	     0xff, 0xff, 0xff, 0, 0xc7} },	/* GET LBA STATUS(16) */
+	{0, 0x9e, 0x16, F_SA_LOW | F_D_IN, resp_get_stream_status, NULL,
+	    {16, 0x16, 0, 0, 0xff, 0xff, 0, 0, 0, 0, 0xff, 0xff, 0xff, 0xff,
+	     0, 0} },	/* GET STREAM STATUS */
 };
 
 static const struct opcode_info_t vl_iarr[] = {	/* VARIABLE LENGTH */
@@ -896,10 +902,12 @@ static int sdeb_zbc_nr_conv = DEF_ZBC_NR_CONV_ZONES;
 static int submit_queues = DEF_SUBMIT_QUEUES;  /* > 1 for multi-queue (mq) */
 static int poll_queues; /* iouring iopoll interface.*/
 
+static atomic_long_t writes_by_group_number[64];
+
 static char sdebug_proc_name[] = MY_NAME;
 static const char *my_name = MY_NAME;
 
-static struct bus_type pseudo_lld_bus;
+static const struct bus_type pseudo_lld_bus;
 
 static struct device_driver sdebug_driverfs_driver = {
 	.name 		= sdebug_proc_name,
@@ -1867,6 +1875,19 @@ static int inquiry_vpd_b6(struct sdebug_dev_info *devip, unsigned char *arr)
 	return 0x3c;
 }
 
+#define SDEBUG_BLE_LEN_AFTER_B4 28	/* thus vpage 32 bytes long */
+
+enum { MAXIMUM_NUMBER_OF_STREAMS = 6, PERMANENT_STREAM_COUNT = 5 };
+
+/* Block limits extension VPD page (SBC-4) */
+static int inquiry_vpd_b7(unsigned char *arrb4)
+{
+	memset(arrb4, 0, SDEBUG_BLE_LEN_AFTER_B4);
+	arrb4[1] = 1; /* Reduced stream control support (RSCS) */
+	put_unaligned_be16(MAXIMUM_NUMBER_OF_STREAMS, &arrb4[2]);
+	return SDEBUG_BLE_LEN_AFTER_B4;
+}
+
 #define SDEBUG_LONG_INQ_SZ 96
 #define SDEBUG_MAX_INQ_ARR_SZ 584
 
@@ -1903,7 +1924,8 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 		u32 len;
 		char lu_id_str[6];
 		int host_no = devip->sdbg_host->shost->host_no;
-		
+
+		arr[1] = cmd[2];
 		port_group_id = (((host_no + 1) & 0x7f) << 8) +
 		    (devip->channel & 0x7f);
 		if (sdebug_vpd_use_hostno == 0)
@@ -1914,7 +1936,6 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 				 (devip->target * 1000) - 3;
 		len = scnprintf(lu_id_str, 6, "%d", lu_id_num);
 		if (0 == cmd[2]) { /* supported vital product data pages */
-			arr[1] = cmd[2];	/*sanity */
 			n = 4;
 			arr[n++] = 0x0;   /* this page */
 			arr[n++] = 0x80;  /* unit serial number */
@@ -1932,26 +1953,22 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 					arr[n++] = 0xb2;  /* LB Provisioning */
 				if (is_zbc)
 					arr[n++] = 0xb6;  /* ZB dev. char. */
+				arr[n++] = 0xb7;  /* Block limits extension */
 			}
 			arr[3] = n - 4;	  /* number of supported VPD pages */
 		} else if (0x80 == cmd[2]) { /* unit serial number */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = len;
 			memcpy(&arr[4], lu_id_str, len);
 		} else if (0x83 == cmd[2]) { /* device identification */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = inquiry_vpd_83(&arr[4], port_group_id,
 						target_dev_id, lu_id_num,
 						lu_id_str, len,
 						&devip->lu_name);
 		} else if (0x84 == cmd[2]) { /* Software interface ident. */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = inquiry_vpd_84(&arr[4]);
 		} else if (0x85 == cmd[2]) { /* Management network addresses */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = inquiry_vpd_85(&arr[4]);
 		} else if (0x86 == cmd[2]) { /* extended inquiry */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = 0x3c;	/* number of following entries */
 			if (sdebug_dif == T10_PI_TYPE3_PROTECTION)
 				arr[4] = 0x4;	/* SPT: GRD_CHK:1 */
@@ -1959,33 +1976,32 @@ static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 				arr[4] = 0x5;   /* SPT: GRD_CHK:1, REF_CHK:1 */
 			else
 				arr[4] = 0x0;   /* no protection stuff */
-			arr[5] = 0x7;   /* head of q, ordered + simple q's */
+			/*
+			 * GROUP_SUP=1; HEADSUP=1 (HEAD OF QUEUE); ORDSUP=1
+			 * (ORDERED queuing); SIMPSUP=1 (SIMPLE queuing).
+			 */
+			arr[5] = 0x17;
 		} else if (0x87 == cmd[2]) { /* mode page policy */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = 0x8;	/* number of following entries */
 			arr[4] = 0x2;	/* disconnect-reconnect mp */
 			arr[6] = 0x80;	/* mlus, shared */
 			arr[8] = 0x18;	 /* protocol specific lu */
 			arr[10] = 0x82;	 /* mlus, per initiator port */
 		} else if (0x88 == cmd[2]) { /* SCSI Ports */
-			arr[1] = cmd[2];	/*sanity */
 			arr[3] = inquiry_vpd_88(&arr[4], target_dev_id);
 		} else if (is_disk_zbc && 0x89 == cmd[2]) { /* ATA info */
-			arr[1] = cmd[2];        /*sanity */
 			n = inquiry_vpd_89(&arr[4]);
 			put_unaligned_be16(n, arr + 2);
 		} else if (is_disk_zbc && 0xb0 == cmd[2]) { /* Block limits */
-			arr[1] = cmd[2];        /*sanity */
 			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(devip, &arr[4]);
 		} else if (is_disk && 0xb2 == cmd[2]) { /* LB Prov. */
-			arr[1] = cmd[2];        /*sanity */
 			arr[3] = inquiry_vpd_b2(&arr[4]);
 		} else if (is_zbc && cmd[2] == 0xb6) { /* ZB dev. charact. */
-			arr[1] = cmd[2];        /*sanity */
 			arr[3] = inquiry_vpd_b6(devip, &arr[4]);
+		} else if (cmd[2] == 0xb7) { /* block limits extension page */
+			arr[3] = inquiry_vpd_b7(&arr[4]);
 		} else {
 			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, -1);
 			kfree(arr);
@@ -2554,6 +2570,40 @@ static int resp_ctrl_m_pg(unsigned char *p, int pcontrol, int target)
 	return sizeof(ctrl_m_pg);
 }
 
+/* IO Advice Hints Grouping mode page */
+static int resp_grouping_m_pg(unsigned char *p, int pcontrol, int target)
+{
+	/* IO Advice Hints Grouping mode page */
+	struct grouping_m_pg {
+		u8 page_code;	/* OR 0x40 when subpage_code > 0 */
+		u8 subpage_code;
+		__be16 page_length;
+		u8 reserved[12];
+		struct scsi_io_group_descriptor descr[MAXIMUM_NUMBER_OF_STREAMS];
+	};
+	static const struct grouping_m_pg gr_m_pg = {
+		.page_code = 0xa | 0x40,
+		.subpage_code = 5,
+		.page_length = cpu_to_be16(sizeof(gr_m_pg) - 4),
+		.descr = {
+			{ .st_enble = 1 },
+			{ .st_enble = 1 },
+			{ .st_enble = 1 },
+			{ .st_enble = 1 },
+			{ .st_enble = 1 },
+			{ .st_enble = 0 },
+		}
+	};
+
+	BUILD_BUG_ON(sizeof(struct grouping_m_pg) !=
+		     16 + MAXIMUM_NUMBER_OF_STREAMS * 16);
+	memcpy(p, &gr_m_pg, sizeof(gr_m_pg));
+	if (1 == pcontrol) {
+		/* There are no changeable values so clear from byte 4 on. */
+		memset(p + 4, 0, sizeof(gr_m_pg) - 4);
+	}
+	return sizeof(gr_m_pg);
+}
 
 static int resp_iec_m_pg(unsigned char *p, int pcontrol, int target)
 {	/* Informational Exceptions control mode page for mode_sense */
@@ -2627,7 +2677,8 @@ static int resp_sas_sha_m_spg(unsigned char *p, int pcontrol)
 	return sizeof(sas_sha_m_pg);
 }
 
-#define SDEBUG_MAX_MSENSE_SZ 256
+/* PAGE_SIZE is more than necessary but provides room for future expansion. */
+#define SDEBUG_MAX_MSENSE_SZ PAGE_SIZE
 
 static int resp_mode_sense(struct scsi_cmnd *scp,
 			   struct sdebug_dev_info *devip)
@@ -2638,10 +2689,13 @@ static int resp_mode_sense(struct scsi_cmnd *scp,
 	int target_dev_id;
 	int target = scp->device->id;
 	unsigned char *ap;
-	unsigned char arr[SDEBUG_MAX_MSENSE_SZ];
+	unsigned char *arr __free(kfree);
 	unsigned char *cmd = scp->cmnd;
-	bool dbd, llbaa, msense_6, is_disk, is_zbc, bad_pcode;
+	bool dbd, llbaa, msense_6, is_disk, is_zbc;
 
+	arr = kzalloc(SDEBUG_MAX_MSENSE_SZ, GFP_ATOMIC);
+	if (!arr)
+		return -ENOMEM;
 	dbd = !!(cmd[1] & 0x8);		/* disable block descriptors */
 	pcontrol = (cmd[2] & 0xc0) >> 6;
 	pcode = cmd[2] & 0x3f;
@@ -2699,45 +2753,63 @@ static int resp_mode_sense(struct scsi_cmnd *scp,
 		ap = arr + offset;
 	}
 
-	if ((subpcode > 0x0) && (subpcode < 0xff) && (0x19 != pcode)) {
-		/* TODO: Control Extension page */
-		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
-		return check_condition_result;
-	}
-	bad_pcode = false;
-
+	/*
+	 * N.B. If len>0 before resp_*_pg() call, then form of that call should be:
+	 *        len += resp_*_pg(ap + len, pcontrol, target);
+	 */
 	switch (pcode) {
 	case 0x1:	/* Read-Write error recovery page, direct access */
+		if (subpcode > 0x0 && subpcode < 0xff)
+			goto bad_subpcode;
 		len = resp_err_recov_pg(ap, pcontrol, target);
 		offset += len;
 		break;
 	case 0x2:	/* Disconnect-Reconnect page, all devices */
+		if (subpcode > 0x0 && subpcode < 0xff)
+			goto bad_subpcode;
 		len = resp_disconnect_pg(ap, pcontrol, target);
 		offset += len;
 		break;
 	case 0x3:       /* Format device page, direct access */
+		if (subpcode > 0x0 && subpcode < 0xff)
+			goto bad_subpcode;
 		if (is_disk) {
 			len = resp_format_pg(ap, pcontrol, target);
 			offset += len;
-		} else
-			bad_pcode = true;
+		} else {
+			goto bad_pcode;
+		}
 		break;
 	case 0x8:	/* Caching page, direct access */
+		if (subpcode > 0x0 && subpcode < 0xff)
+			goto bad_subpcode;
 		if (is_disk || is_zbc) {
 			len = resp_caching_pg(ap, pcontrol, target);
 			offset += len;
-		} else
-			bad_pcode = true;
+		} else {
+			goto bad_pcode;
+		}
 		break;
 	case 0xa:	/* Control Mode page, all devices */
-		len = resp_ctrl_m_pg(ap, pcontrol, target);
+		switch (subpcode) {
+		case 0:
+			len = resp_ctrl_m_pg(ap, pcontrol, target);
+			break;
+		case 0x05:
+			len = resp_grouping_m_pg(ap, pcontrol, target);
+			break;
+		case 0xff:
+			len = resp_ctrl_m_pg(ap, pcontrol, target);
+			len += resp_grouping_m_pg(ap + len, pcontrol, target);
+			break;
+		default:
+			goto bad_subpcode;
+		}
 		offset += len;
 		break;
 	case 0x19:	/* if spc==1 then sas phy, control+discover */
-		if ((subpcode > 0x2) && (subpcode < 0xff)) {
-			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
-			return check_condition_result;
-		}
+		if (subpcode > 0x2 && subpcode < 0xff)
+			goto bad_subpcode;
 		len = 0;
 		if ((0x0 == subpcode) || (0xff == subpcode))
 			len += resp_sas_sf_m_pg(ap + len, pcontrol, target);
@@ -2749,49 +2821,50 @@ static int resp_mode_sense(struct scsi_cmnd *scp,
 		offset += len;
 		break;
 	case 0x1c:	/* Informational Exceptions Mode page, all devices */
+		if (subpcode > 0x0 && subpcode < 0xff)
+			goto bad_subpcode;
 		len = resp_iec_m_pg(ap, pcontrol, target);
 		offset += len;
 		break;
 	case 0x3f:	/* Read all Mode pages */
-		if ((0 == subpcode) || (0xff == subpcode)) {
-			len = resp_err_recov_pg(ap, pcontrol, target);
-			len += resp_disconnect_pg(ap + len, pcontrol, target);
-			if (is_disk) {
-				len += resp_format_pg(ap + len, pcontrol,
-						      target);
-				len += resp_caching_pg(ap + len, pcontrol,
-						       target);
-			} else if (is_zbc) {
-				len += resp_caching_pg(ap + len, pcontrol,
-						       target);
-			}
-			len += resp_ctrl_m_pg(ap + len, pcontrol, target);
-			len += resp_sas_sf_m_pg(ap + len, pcontrol, target);
-			if (0xff == subpcode) {
-				len += resp_sas_pcd_m_spg(ap + len, pcontrol,
-						  target, target_dev_id);
-				len += resp_sas_sha_m_spg(ap + len, pcontrol);
-			}
-			len += resp_iec_m_pg(ap + len, pcontrol, target);
-			offset += len;
-		} else {
-			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
-			return check_condition_result;
+		if (subpcode > 0x0 && subpcode < 0xff)
+			goto bad_subpcode;
+		len = resp_err_recov_pg(ap, pcontrol, target);
+		len += resp_disconnect_pg(ap + len, pcontrol, target);
+		if (is_disk) {
+			len += resp_format_pg(ap + len, pcontrol, target);
+			len += resp_caching_pg(ap + len, pcontrol, target);
+		} else if (is_zbc) {
+			len += resp_caching_pg(ap + len, pcontrol, target);
 		}
+		len += resp_ctrl_m_pg(ap + len, pcontrol, target);
+		if (0xff == subpcode)
+			len += resp_grouping_m_pg(ap + len, pcontrol, target);
+		len += resp_sas_sf_m_pg(ap + len, pcontrol, target);
+		if (0xff == subpcode) {
+			len += resp_sas_pcd_m_spg(ap + len, pcontrol, target,
+						  target_dev_id);
+			len += resp_sas_sha_m_spg(ap + len, pcontrol);
+		}
+		len += resp_iec_m_pg(ap + len, pcontrol, target);
+		offset += len;
 		break;
 	default:
-		bad_pcode = true;
-		break;
-	}
-	if (bad_pcode) {
-		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
-		return check_condition_result;
+		goto bad_pcode;
 	}
 	if (msense_6)
 		arr[0] = offset - 1;
 	else
 		put_unaligned_be16((offset - 2), arr + 0);
 	return fill_from_dev_buffer(scp, arr, min_t(u32, alloc_len, offset));
+
+bad_pcode:
+	mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
+	return check_condition_result;
+
+bad_subpcode:
+	mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
+	return check_condition_result;
 }
 
 #define SDEBUG_MAX_MSELECT_SZ 512
@@ -3306,7 +3379,8 @@ static inline struct sdeb_store_info *devip2sip(struct sdebug_dev_info *devip,
 
 /* Returns number of bytes copied or -1 if error. */
 static int do_device_access(struct sdeb_store_info *sip, struct scsi_cmnd *scp,
-			    u32 sg_skip, u64 lba, u32 num, bool do_write)
+			    u32 sg_skip, u64 lba, u32 num, bool do_write,
+			    u8 group_number)
 {
 	int ret;
 	u64 block, rest = 0;
@@ -3325,6 +3399,10 @@ static int do_device_access(struct sdeb_store_info *sip, struct scsi_cmnd *scp,
 		return 0;
 	if (scp->sc_data_direction != dir)
 		return -1;
+
+	if (do_write && group_number < ARRAY_SIZE(writes_by_group_number))
+		atomic_long_inc(&writes_by_group_number[group_number]);
+
 	fsp = sip->storep;
 
 	block = do_div(lba, sdebug_store_sectors);
@@ -3698,7 +3776,7 @@ static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 		}
 	}
 
-	ret = do_device_access(sip, scp, 0, lba, num, false);
+	ret = do_device_access(sip, scp, 0, lba, num, false, 0);
 	sdeb_read_unlock(sip);
 	if (unlikely(ret == -1))
 		return DID_ERROR << 16;
@@ -3883,6 +3961,7 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
 	bool check_prot;
 	u32 num;
+	u8 group = 0;
 	u32 ei_lba;
 	int ret;
 	u64 lba;
@@ -3894,11 +3973,13 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 		ei_lba = 0;
 		lba = get_unaligned_be64(cmd + 2);
 		num = get_unaligned_be32(cmd + 10);
+		group = cmd[14] & 0x3f;
 		check_prot = true;
 		break;
 	case WRITE_10:
 		ei_lba = 0;
 		lba = get_unaligned_be32(cmd + 2);
+		group = cmd[6] & 0x3f;
 		num = get_unaligned_be16(cmd + 7);
 		check_prot = true;
 		break;
@@ -3913,15 +3994,18 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 		ei_lba = 0;
 		lba = get_unaligned_be32(cmd + 2);
 		num = get_unaligned_be32(cmd + 6);
+		group = cmd[6] & 0x3f;
 		check_prot = true;
 		break;
 	case 0x53:	/* XDWRITEREAD(10) */
 		ei_lba = 0;
 		lba = get_unaligned_be32(cmd + 2);
+		group = cmd[6] & 0x1f;
 		num = get_unaligned_be16(cmd + 7);
 		check_prot = false;
 		break;
 	default:	/* assume WRITE(32) */
+		group = cmd[6] & 0x3f;
 		lba = get_unaligned_be64(cmd + 12);
 		ei_lba = get_unaligned_be32(cmd + 20);
 		num = get_unaligned_be32(cmd + 28);
@@ -3976,7 +4060,7 @@ static int resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 		}
 	}
 
-	ret = do_device_access(sip, scp, 0, lba, num, true);
+	ret = do_device_access(sip, scp, 0, lba, num, true, group);
 	if (unlikely(scsi_debug_lbp()))
 		map_region(sip, lba, num);
 	/* If ZBC zone then bump its write pointer */
@@ -4028,12 +4112,14 @@ static int resp_write_scat(struct scsi_cmnd *scp,
 	u32 lb_size = sdebug_sector_size;
 	u32 ei_lba;
 	u64 lba;
+	u8 group;
 	int ret, res;
 	bool is_16;
 	static const u32 lrd_size = 32; /* + parameter list header size */
 
 	if (cmd[0] == VARIABLE_LENGTH_CMD) {
 		is_16 = false;
+		group = cmd[6] & 0x3f;
 		wrprotect = (cmd[10] >> 5) & 0x7;
 		lbdof = get_unaligned_be16(cmd + 12);
 		num_lrd = get_unaligned_be16(cmd + 16);
@@ -4044,6 +4130,7 @@ static int resp_write_scat(struct scsi_cmnd *scp,
 		lbdof = get_unaligned_be16(cmd + 4);
 		num_lrd = get_unaligned_be16(cmd + 8);
 		bt_len = get_unaligned_be32(cmd + 10);
+		group = cmd[14] & 0x3f;
 		if (unlikely(have_dif_prot)) {
 			if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
 			    wrprotect) {
@@ -4132,7 +4219,7 @@ static int resp_write_scat(struct scsi_cmnd *scp,
 			}
 		}
 
-		ret = do_device_access(sip, scp, sg_off, lba, num, true);
+		ret = do_device_access(sip, scp, sg_off, lba, num, true, group);
 		/* If ZBC zone then bump its write pointer */
 		if (sdebug_dev_is_zoned(devip))
 			zbc_inc_wp(devip, lba, num);
@@ -4507,6 +4594,51 @@ static int resp_get_lba_status(struct scsi_cmnd *scp,
 	return fill_from_dev_buffer(scp, arr, SDEBUG_GET_LBA_STATUS_LEN);
 }
 
+static int resp_get_stream_status(struct scsi_cmnd *scp,
+				  struct sdebug_dev_info *devip)
+{
+	u16 starting_stream_id, stream_id;
+	const u8 *cmd = scp->cmnd;
+	u32 alloc_len, offset;
+	u8 arr[256] = {};
+	struct scsi_stream_status_header *h = (void *)arr;
+
+	starting_stream_id = get_unaligned_be16(cmd + 4);
+	alloc_len = get_unaligned_be32(cmd + 10);
+
+	if (alloc_len < 8) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 10, -1);
+		return check_condition_result;
+	}
+
+	if (starting_stream_id >= MAXIMUM_NUMBER_OF_STREAMS) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, -1);
+		return check_condition_result;
+	}
+
+	/*
+	 * The GET STREAM STATUS command only reports status information
+	 * about open streams. Treat the non-permanent stream as open.
+	 */
+	put_unaligned_be16(MAXIMUM_NUMBER_OF_STREAMS,
+			   &h->number_of_open_streams);
+
+	for (offset = 8, stream_id = starting_stream_id;
+	     offset + 8 <= min_t(u32, alloc_len, sizeof(arr)) &&
+		     stream_id < MAXIMUM_NUMBER_OF_STREAMS;
+	     offset += 8, stream_id++) {
+		struct scsi_stream_status *stream_status = (void *)arr + offset;
+
+		stream_status->perm = stream_id < PERMANENT_STREAM_COUNT;
+		put_unaligned_be16(stream_id,
+				   &stream_status->stream_identifier);
+		stream_status->rel_lifetime = stream_id + 1;
+	}
+	put_unaligned_be32(offset - 8, &h->len); /* PARAMETER DATA LENGTH */
+
+	return fill_from_dev_buffer(scp, arr, min(offset, alloc_len));
+}
+
 static int resp_sync_cache(struct scsi_cmnd *scp,
 			   struct sdebug_dev_info *devip)
 {
@@ -7182,6 +7314,30 @@ static ssize_t tur_ms_to_ready_show(struct device_driver *ddp, char *buf)
 }
 static DRIVER_ATTR_RO(tur_ms_to_ready);
 
+static ssize_t group_number_stats_show(struct device_driver *ddp, char *buf)
+{
+	char *p = buf, *end = buf + PAGE_SIZE;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(writes_by_group_number); i++)
+		p += scnprintf(p, end - p, "%d %ld\n", i,
+			       atomic_long_read(&writes_by_group_number[i]));
+
+	return p - buf;
+}
+
+static ssize_t group_number_stats_store(struct device_driver *ddp,
+					const char *buf, size_t count)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(writes_by_group_number); i++)
+		atomic_long_set(&writes_by_group_number[i], 0);
+
+	return count;
+}
+static DRIVER_ATTR_RW(group_number_stats);
+
 /* Note: The following array creates attribute files in the
    /sys/bus/pseudo/drivers/scsi_debug directory. The advantage of these
    files (over those found in the /sys/module/scsi_debug/parameters
@@ -7228,6 +7384,7 @@ static struct attribute *sdebug_drv_attrs[] = {
 	&driver_attr_cdb_len.attr,
 	&driver_attr_tur_ms_to_ready.attr,
 	&driver_attr_zbc.attr,
+	&driver_attr_group_number_stats.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(sdebug_drv);
@@ -8405,7 +8562,7 @@ static void sdebug_driver_remove(struct device *dev)
 	scsi_host_put(sdbg_host->shost);
 }
 
-static struct bus_type pseudo_lld_bus = {
+static const struct bus_type pseudo_lld_bus = {
 	.name = "pseudo",
 	.probe = sdebug_driver_probe,
 	.remove = sdebug_driver_remove,