diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index ee99aca..2181427 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -71,10 +71,10 @@
 /* Additional Sense Code (ASC) */
 #define NO_ADDITIONAL_SENSE 0x0
 #define LOGICAL_UNIT_NOT_READY 0x4
+#define LOGICAL_UNIT_COMMUNICATION_FAILURE 0x8
 #define UNRECOVERED_READ_ERR 0x11
 #define PARAMETER_LIST_LENGTH_ERR 0x1a
 #define INVALID_OPCODE 0x20
-#define INVALID_COMMAND_OPCODE 0x20
 #define LBA_OUT_OF_RANGE 0x21
 #define INVALID_FIELD_IN_CDB 0x24
 #define INVALID_FIELD_IN_PARAM_LIST 0x26
@@ -136,6 +136,7 @@
 #define DEF_VIRTUAL_GB   0
 #define DEF_VPD_USE_HOSTNO 1
 #define DEF_WRITESAME_LENGTH 0xFFFF
+#define DEF_STRICT 0
 #define DELAY_OVERRIDDEN -9999
 
 /* bit mask values for scsi_debug_opts */
@@ -183,8 +184,8 @@
 #define SDEBUG_NUM_UAS 4
 
 /* for check_readiness() */
-#define UAS_ONLY 1
-#define UAS_TUR 0
+#define UAS_ONLY 1	/* check for UAs only */
+#define UAS_TUR 0	/* if no UAs then check if media access possible */
 
 /* when 1==SCSI_DEBUG_OPT_MEDIUM_ERR, a medium error is simulated at this
  * sector on read commands: */
@@ -210,6 +211,291 @@
 #warning "Expect DEF_CMD_PER_LUN <= SCSI_DEBUG_CANQUEUE"
 #endif
 
+/* SCSI opcodes (first byte of cdb) mapped onto these indexes */
+enum sdeb_opcode_index {
+	SDEB_I_INVALID_OPCODE =	0,
+	SDEB_I_INQUIRY = 1,
+	SDEB_I_REPORT_LUNS = 2,
+	SDEB_I_REQUEST_SENSE = 3,
+	SDEB_I_TEST_UNIT_READY = 4,
+	SDEB_I_MODE_SENSE = 5,		/* 6, 10 */
+	SDEB_I_MODE_SELECT = 6,		/* 6, 10 */
+	SDEB_I_LOG_SENSE = 7,
+	SDEB_I_READ_CAPACITY = 8,	/* 10; 16 is in SA_IN(16) */
+	SDEB_I_READ = 9,		/* 6, 10, 12, 16 */
+	SDEB_I_WRITE = 10,		/* 6, 10, 12, 16 */
+	SDEB_I_START_STOP = 11,
+	SDEB_I_SERV_ACT_IN = 12,	/* 12, 16 */
+	SDEB_I_SERV_ACT_OUT = 13,	/* 12, 16 */
+	SDEB_I_MAINT_IN = 14,
+	SDEB_I_MAINT_OUT = 15,
+	SDEB_I_VERIFY = 16,		/* 10 only */
+	SDEB_I_VARIABLE_LEN = 17,
+	SDEB_I_RESERVE = 18,		/* 6, 10 */
+	SDEB_I_RELEASE = 19,		/* 6, 10 */
+	SDEB_I_ALLOW_REMOVAL = 20,	/* PREVENT ALLOW MEDIUM REMOVAL */
+	SDEB_I_REZERO_UNIT = 21,	/* REWIND in SSC */
+	SDEB_I_ATA_PT = 22,		/* 12, 16 */
+	SDEB_I_SEND_DIAG = 23,
+	SDEB_I_UNMAP = 24,
+	SDEB_I_XDWRITEREAD = 25,	/* 10 only */
+	SDEB_I_WRITE_BUFFER = 26,
+	SDEB_I_WRITE_SAME = 27,		/* 10, 16 */
+	SDEB_I_SYNC_CACHE = 28,		/* 10 only */
+	SDEB_I_COMP_WRITE = 29,
+	SDEB_I_LAST_ELEMENT = 30,	/* keep this last */
+};
+
+static const unsigned char opcode_ind_arr[256] = {
+/* 0x0; 0x0->0x1f: 6 byte cdbs */
+	SDEB_I_TEST_UNIT_READY, SDEB_I_REZERO_UNIT, 0, SDEB_I_REQUEST_SENSE,
+	    0, 0, 0, 0,
+	SDEB_I_READ, 0, SDEB_I_WRITE, 0, 0, 0, 0, 0,
+	0, 0, SDEB_I_INQUIRY, 0, 0, SDEB_I_MODE_SELECT, SDEB_I_RESERVE,
+	    SDEB_I_RELEASE,
+	0, 0, SDEB_I_MODE_SENSE, SDEB_I_START_STOP, 0, SDEB_I_SEND_DIAG,
+	    SDEB_I_ALLOW_REMOVAL, 0,
+/* 0x20; 0x20->0x3f: 10 byte cdbs */
+	0, 0, 0, 0, 0, SDEB_I_READ_CAPACITY, 0, 0,
+	SDEB_I_READ, 0, SDEB_I_WRITE, 0, 0, 0, 0, SDEB_I_VERIFY,
+	0, 0, 0, 0, 0, SDEB_I_SYNC_CACHE, 0, 0,
+	0, 0, 0, SDEB_I_WRITE_BUFFER, 0, 0, 0, 0,
+/* 0x40; 0x40->0x5f: 10 byte cdbs */
+	0, SDEB_I_WRITE_SAME, SDEB_I_UNMAP, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, SDEB_I_LOG_SENSE, 0, 0,
+	0, 0, 0, SDEB_I_XDWRITEREAD, 0, SDEB_I_MODE_SELECT, SDEB_I_RESERVE,
+	    SDEB_I_RELEASE,
+	0, 0, SDEB_I_MODE_SENSE, 0, 0, 0, 0, 0,
+/* 0x60; 0x60->0x7d are reserved */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, SDEB_I_VARIABLE_LEN,
+/* 0x80; 0x80->0x9f: 16 byte cdbs */
+	0, 0, 0, 0, 0, SDEB_I_ATA_PT, 0, 0,
+	SDEB_I_READ, SDEB_I_COMP_WRITE, SDEB_I_WRITE, 0, 0, 0, 0, 0,
+	0, 0, 0, SDEB_I_WRITE_SAME, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, SDEB_I_SERV_ACT_IN, SDEB_I_SERV_ACT_OUT,
+/* 0xa0; 0xa0->0xbf: 12 byte cdbs */
+	SDEB_I_REPORT_LUNS, SDEB_I_ATA_PT, 0, SDEB_I_MAINT_IN,
+	     SDEB_I_MAINT_OUT, 0, 0, 0,
+	SDEB_I_READ, SDEB_I_SERV_ACT_OUT, SDEB_I_WRITE, SDEB_I_SERV_ACT_IN,
+	     0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0,
+/* 0xc0; 0xc0->0xff: vendor specific */
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+};
+
+#define F_D_IN			1
+#define F_D_OUT			2
+#define F_D_OUT_MAYBE		4	/* WRITE SAME, NDOB bit */
+#define F_D_UNKN		8
+#define F_RL_WLUN_OK		0x10
+#define F_SKIP_UA		0x20
+#define F_DELAY_OVERR		0x40
+#define F_SA_LOW		0x80	/* cdb byte 1, bits 4 to 0 */
+#define F_SA_HIGH		0x100	/* as used by variable length cdbs */
+#define F_INV_OP		0x200
+#define F_FAKE_RW		0x400
+#define F_M_ACCESS		0x800	/* media access */
+
+#define FF_RESPOND (F_RL_WLUN_OK | F_SKIP_UA | F_DELAY_OVERR)
+#define FF_DIRECT_IO (F_M_ACCESS | F_FAKE_RW)
+#define FF_SA (F_SA_HIGH | F_SA_LOW)
+
+struct sdebug_dev_info;
+static int scsi_debug_queuecommand(struct scsi_cmnd *scp);
+static int resp_inquiry(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_report_luns(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_requests(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_mode_sense(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_mode_select(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_log_sense(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_readcap(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_read_dt0(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_write_dt0(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_report_tgtpgs(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_unmap(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_write_same_10(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_write_same_16(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_xdwriteread_10(struct scsi_cmnd *, struct sdebug_dev_info *);
+
+struct opcode_info_t {
+	u8 num_attached;	/* 0 if this is it (i.e. a leaf); use 0xff
+				 * for terminating element */
+	u8 opcode;		/* if num_attached > 0, preferred */
+	u16 sa;			/* service action */
+	u32 flags;		/* OR-ed set of SDEB_F_* */
+	int (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *);
+	const struct opcode_info_t *arrp;  /* num_attached elements or NULL */
+	u8 len_mask[16];	/* len=len_mask[0], then mask for cdb[1]... */
+				/* ignore cdb bytes after position 15 */
+};
+
+static const struct opcode_info_t msense_iarr[1] = {
+	{0, 0x1a, 0, F_D_IN, NULL, NULL,
+	    {6,  0xe8, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+};
+
+static const struct opcode_info_t mselect_iarr[1] = {
+	{0, 0x15, 0, F_D_OUT, NULL, NULL,
+	    {6,  0xf1, 0, 0, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+};
+
+static const struct opcode_info_t read_iarr[3] = {
+	{0, 0x28, 0, F_D_IN | FF_DIRECT_IO, resp_read_dt0, NULL,/* READ(10) */
+	    {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x1f, 0xff, 0xff, 0xc7, 0, 0,
+	     0, 0, 0, 0} },
+	{0, 0x8, 0, F_D_IN | FF_DIRECT_IO, resp_read_dt0, NULL, /* READ(6) */
+	    {6,  0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0xa8, 0, F_D_IN | FF_DIRECT_IO, resp_read_dt0, NULL,/* READ(12) */
+	    {12,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x9f,
+	     0xc7, 0, 0, 0, 0} },
+};
+
+static const struct opcode_info_t write_iarr[3] = {
+	{0, 0x2a, 0, F_D_OUT | FF_DIRECT_IO, resp_write_dt0, NULL,   /* 10 */
+	    {10,  0xfb, 0xff, 0xff, 0xff, 0xff, 0x1f, 0xff, 0xff, 0xc7, 0, 0,
+	     0, 0, 0, 0} },
+	{0, 0xa, 0, F_D_OUT | FF_DIRECT_IO, resp_write_dt0, NULL,    /* 6 */
+	    {6,  0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0xaa, 0, F_D_OUT | FF_DIRECT_IO, resp_write_dt0, NULL,   /* 12 */
+	    {12,  0xfb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x9f,
+	     0xc7, 0, 0, 0, 0} },
+};
+
+static const struct opcode_info_t sa_in_iarr[1] = {
+	{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} },
+};
+
+static const struct opcode_info_t vl_iarr[1] = {	/* VARIABLE LENGTH */
+	{0, 0x7f, 0xb, F_SA_HIGH | F_D_OUT | FF_DIRECT_IO, resp_write_dt0,
+	    NULL, {32,  0xc7, 0, 0, 0, 0, 0x1f, 0x18, 0x0, 0xb, 0xfa,
+		   0, 0xff, 0xff, 0xff, 0xff} },	/* WRITE(32) */
+};
+
+static const struct opcode_info_t maint_in_iarr[2] = {
+	{0, 0xa3, 0xc, F_SA_LOW | F_D_IN, NULL, NULL,
+	    {12,  0xc, 0x87, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0,
+	     0xc7, 0, 0, 0, 0} },
+	{0, 0xa3, 0xd, F_SA_LOW | F_D_IN, NULL, NULL,
+	    {12,  0xd, 0x80, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0, 0xc7, 0, 0,
+	     0, 0} },
+};
+
+static const struct opcode_info_t write_same_iarr[1] = {
+	{0, 0x93, 0, F_D_OUT_MAYBE | FF_DIRECT_IO, resp_write_same_16, NULL,
+	    {16,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	     0xff, 0xff, 0xff, 0x1f, 0xc7} },
+};
+
+static const struct opcode_info_t reserve_iarr[1] = {
+	{0, 0x16, 0, F_D_OUT, NULL, NULL,	/* RESERVE(6) */
+	    {6,  0x1f, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+};
+
+static const struct opcode_info_t release_iarr[1] = {
+	{0, 0x17, 0, F_D_OUT, NULL, NULL,	/* RELEASE(6) */
+	    {6,  0x1f, 0xff, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+};
+
+
+/* This array is accessed via SDEB_I_* values. Make sure all are mapped,
+ * plus the terminating elements for logic that scans this table such as
+ * REPORT SUPPORTED OPERATION CODES. */
+static const struct opcode_info_t opcode_info_arr[SDEB_I_LAST_ELEMENT + 1] = {
+/* 0 */
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL,
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0x12, 0, FF_RESPOND | F_D_IN, resp_inquiry, NULL,
+	    {6,  0xe3, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0xa0, 0, FF_RESPOND | F_D_IN, resp_report_luns, NULL,
+	    {12,  0xe3, 0xff, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0, 0xc7, 0, 0,
+	     0, 0} },
+	{0, 0x3, 0, FF_RESPOND | F_D_IN, resp_requests, NULL,
+	    {6,  0xe1, 0, 0, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0x0, 0, F_M_ACCESS | F_RL_WLUN_OK, NULL, NULL,/* TEST UNIT READY */
+	    {6,  0, 0, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{1, 0x5a, 0, F_D_IN, resp_mode_sense, msense_iarr,
+	    {10,  0xf8, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
+	     0} },
+	{1, 0x55, 0, F_D_OUT, resp_mode_select, mselect_iarr,
+	    {10,  0xf1, 0, 0, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
+	{0, 0x4d, 0, F_D_IN, resp_log_sense, NULL,
+	    {10,  0xe3, 0xff, 0xff, 0, 0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0,
+	     0, 0, 0} },
+	{0, 0x25, 0, F_D_IN, resp_readcap, NULL,
+	    {10,  0xe1, 0xff, 0xff, 0xff, 0xff, 0, 0, 0x1, 0xc7, 0, 0, 0, 0,
+	     0, 0} },
+	{3, 0x88, 0, F_D_IN | FF_DIRECT_IO, resp_read_dt0, read_iarr,
+	    {16,  0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	     0xff, 0xff, 0xff, 0x9f, 0xc7} },		/* READ(16) */
+/* 10 */
+	{3, 0x8a, 0, F_D_OUT | FF_DIRECT_IO, resp_write_dt0, write_iarr,
+	    {16,  0xfa, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	     0xff, 0xff, 0xff, 0x9f, 0xc7} },		/* WRITE(16) */
+	{0, 0x1b, 0, 0, resp_start_stop, NULL,		/* START STOP UNIT */
+	    {6,  0x1, 0, 0xf, 0xf7, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{1, 0x9e, 0x10, F_SA_LOW | F_D_IN, resp_readcap16, sa_in_iarr,
+	    {16,  0x10, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	     0xff, 0xff, 0xff, 0x1, 0xc7} },	/* READ CAPACITY(16) */
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* SA OUT */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{2, 0xa3, 0xa, F_SA_LOW | F_D_IN, resp_report_tgtpgs, maint_in_iarr,
+	    {12,  0xea, 0, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0, 0xc7, 0, 0, 0,
+	     0} },
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* MAINT OUT */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* VERIFY */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{1, 0x7f, 0x9, F_SA_HIGH | F_D_IN | FF_DIRECT_IO, resp_read_dt0,
+	    vl_iarr, {32,  0xc7, 0, 0, 0, 0, 0x1f, 0x18, 0x0, 0x9, 0xfe, 0,
+		      0xff, 0xff, 0xff, 0xff} },/* VARIABLE LENGTH, READ(32) */
+	{1, 0x56, 0, F_D_OUT, NULL, reserve_iarr, /* RESERVE(10) */
+	    {10,  0xff, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
+	     0} },
+	{1, 0x57, 0, F_D_OUT, NULL, release_iarr, /* RELEASE(10) */
+	    {10,  0x13, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
+	     0} },
+/* 20 */
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* ALLOW REMOVAL */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0x1, 0, 0, resp_start_stop, NULL, /* REWIND ?? */
+	    {6,  0x1, 0, 0, 0, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* ATA_PT */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0x1d, F_D_OUT, 0, NULL, NULL,	/* SEND DIAGNOSTIC */
+	    {6,  0xf7, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{0, 0x42, 0, F_D_OUT | FF_DIRECT_IO, resp_unmap, NULL, /* UNMAP */
+	    {10,  0x1, 0, 0, 0, 0, 0x1f, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
+	{0, 0x53, 0, F_D_IN | F_D_OUT | FF_DIRECT_IO, resp_xdwriteread_10,
+	    NULL, {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x1f, 0xff, 0xff, 0xc7,
+		   0, 0, 0, 0, 0, 0} },
+	{0, 0, 0, F_INV_OP | FF_RESPOND, NULL, NULL, /* WRITE_BUFFER */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{1, 0x41, 0, F_D_OUT_MAYBE | FF_DIRECT_IO, resp_write_same_10,
+	    write_same_iarr, {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x1f, 0xff,
+			      0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
+	{0, 0x35, 0, F_DELAY_OVERR | FF_DIRECT_IO, NULL, NULL, /* SYNC_CACHE */
+	    {10,  0x7, 0xff, 0xff, 0xff, 0xff, 0x1f, 0xff, 0xff, 0xc7, 0, 0,
+	     0, 0, 0, 0} },
+	{0, 0x89, 0, F_D_OUT | FF_DIRECT_IO, NULL, NULL,
+	    {16,  0xf8, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0,
+	     0, 0xff, 0x1f, 0xc7} },		/* COMPARE AND WRITE */
+
+/* 30 */
+	{0xff, 0, 0, 0, NULL, NULL,		/* terminating element */
+	    {0,  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+};
+
 struct sdebug_scmd_extra_t {
 	bool inj_recovered;
 	bool inj_transport;
@@ -257,6 +543,7 @@
 static bool scsi_debug_removable = DEF_REMOVABLE;
 static bool scsi_debug_clustering;
 static bool scsi_debug_host_lock = DEF_HOST_LOCK;
+static bool scsi_debug_strict = DEF_STRICT;
 static bool sdebug_any_injecting_opt;
 
 static atomic_t sdebug_cmnd_count;
@@ -290,11 +577,10 @@
 	unsigned int target;
 	u64 lun;
 	struct sdebug_host_info *sdbg_host;
-	u64 wlun;
 	unsigned long uas_bm[1];
 	atomic_t num_in_q;
-	char stopped;
-	char used;
+	char stopped;		/* TODO: should be atomic */
+	bool used;
 };
 
 struct sdebug_host_info {
@@ -477,65 +763,6 @@
 	mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_OPCODE, 0);
 }
 
-static void get_data_transfer_info(unsigned char *cmd,
-				   unsigned long long *lba, unsigned int *num,
-				   u32 *ei_lba)
-{
-	*ei_lba = 0;
-
-	switch (*cmd) {
-	case VARIABLE_LENGTH_CMD:
-		*lba = (u64)cmd[19] | (u64)cmd[18] << 8 |
-			(u64)cmd[17] << 16 | (u64)cmd[16] << 24 |
-			(u64)cmd[15] << 32 | (u64)cmd[14] << 40 |
-			(u64)cmd[13] << 48 | (u64)cmd[12] << 56;
-
-		*ei_lba = (u32)cmd[23] | (u32)cmd[22] << 8 |
-			(u32)cmd[21] << 16 | (u32)cmd[20] << 24;
-
-		*num = (u32)cmd[31] | (u32)cmd[30] << 8 | (u32)cmd[29] << 16 |
-			(u32)cmd[28] << 24;
-		break;
-
-	case WRITE_SAME_16:
-	case WRITE_16:
-	case READ_16:
-		*lba = (u64)cmd[9] | (u64)cmd[8] << 8 |
-			(u64)cmd[7] << 16 | (u64)cmd[6] << 24 |
-			(u64)cmd[5] << 32 | (u64)cmd[4] << 40 |
-			(u64)cmd[3] << 48 | (u64)cmd[2] << 56;
-
-		*num = (u32)cmd[13] | (u32)cmd[12] << 8 | (u32)cmd[11] << 16 |
-			(u32)cmd[10] << 24;
-		break;
-	case WRITE_12:
-	case READ_12:
-		*lba = (u32)cmd[5] | (u32)cmd[4] << 8 | (u32)cmd[3] << 16 |
-			(u32)cmd[2] << 24;
-
-		*num = (u32)cmd[9] | (u32)cmd[8] << 8 | (u32)cmd[7] << 16 |
-			(u32)cmd[6] << 24;
-		break;
-	case WRITE_SAME:
-	case WRITE_10:
-	case READ_10:
-	case XDWRITEREAD_10:
-		*lba = (u32)cmd[5] | (u32)cmd[4] << 8 |	(u32)cmd[3] << 16 |
-			(u32)cmd[2] << 24;
-
-		*num = (u32)cmd[8] | (u32)cmd[7] << 8;
-		break;
-	case WRITE_6:
-	case READ_6:
-		*lba = (u32)cmd[3] | (u32)cmd[2] << 8 |
-			(u32)(cmd[1] & 0x1f) << 16;
-		*num = (0 == cmd[4]) ? 256 : cmd[4];
-		break;
-	default:
-		break;
-	}
-}
-
 static int scsi_debug_ioctl(struct scsi_device *dev, int cmd, void __user *arg)
 {
 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) {
@@ -992,19 +1219,20 @@
 #define SDEBUG_LONG_INQ_SZ 96
 #define SDEBUG_MAX_INQ_ARR_SZ 584
 
-static int resp_inquiry(struct scsi_cmnd *scp, int target,
-			struct sdebug_dev_info * devip)
+static int resp_inquiry(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
 	unsigned char pq_pdt;
 	unsigned char * arr;
 	unsigned char *cmd = scp->cmnd;
 	int alloc_len, n, ret;
+	bool have_wlun;
 
 	alloc_len = (cmd[3] << 8) + cmd[4];
 	arr = kzalloc(SDEBUG_MAX_INQ_ARR_SZ, GFP_ATOMIC);
 	if (! arr)
 		return DID_REQUEUE << 16;
-	if (devip->wlun)
+	have_wlun = (scp->device->lun == SAM2_WLUN_REPORT_LUNS);
+	if (have_wlun)
 		pq_pdt = 0x1e;	/* present, wlun */
 	else if (scsi_debug_no_lun_0 && (0 == devip->lun))
 		pq_pdt = 0x7f;	/* not present, no device type */
@@ -1024,7 +1252,7 @@
 		    (devip->channel & 0x7f);
 		if (0 == scsi_debug_vpd_use_hostno)
 			host_no = 0;
-		lu_id_num = devip->wlun ? -1 : (((host_no + 1) * 2000) +
+		lu_id_num = have_wlun ? -1 : (((host_no + 1) * 2000) +
 			    (devip->target * 1000) + devip->lun);
 		target_dev_id = ((host_no + 1) * 2000) +
 				 (devip->target * 1000) - 3;
@@ -1142,18 +1370,20 @@
 	unsigned char * sbuff;
 	unsigned char *cmd = scp->cmnd;
 	unsigned char arr[SCSI_SENSE_BUFFERSIZE];
-	int want_dsense;
+	bool dsense, want_dsense;
 	int len = 18;
 
 	memset(arr, 0, sizeof(arr));
-	want_dsense = !!(cmd[1] & 1) || scsi_debug_dsense;
+	dsense = !!(cmd[1] & 1);
+	want_dsense = dsense || scsi_debug_dsense;
 	sbuff = scp->sense_buffer;
 	if ((iec_m_pg[2] & 0x4) && (6 == (iec_m_pg[3] & 0xf))) {
-		if (want_dsense) {
+		if (dsense) {
 			arr[0] = 0x72;
 			arr[1] = 0x0;		/* NO_SENSE in sense_key */
 			arr[2] = THRESHOLD_EXCEEDED;
 			arr[3] = 0xff;		/* TEST set and MRIE==6 */
+			len = 8;
 		} else {
 			arr[0] = 0x70;
 			arr[2] = 0x0;		/* NO_SENSE in sense_key */
@@ -1163,15 +1393,34 @@
 		}
 	} else {
 		memcpy(arr, sbuff, SCSI_SENSE_BUFFERSIZE);
-		if ((cmd[1] & 1) && (! scsi_debug_dsense)) {
-			/* DESC bit set and sense_buff in fixed format */
-			memset(arr, 0, sizeof(arr));
+		if (arr[0] >= 0x70 && dsense == scsi_debug_dsense)
+			;	/* have sense and formats match */
+		else if (arr[0] <= 0x70) {
+			if (dsense) {
+				memset(arr, 0, 8);
+				arr[0] = 0x72;
+				len = 8;
+			} else {
+				memset(arr, 0, 18);
+				arr[0] = 0x70;
+				arr[7] = 0xa;
+			}
+		} else if (dsense) {
+			memset(arr, 0, 8);
 			arr[0] = 0x72;
 			arr[1] = sbuff[2];     /* sense key */
 			arr[2] = sbuff[12];    /* asc */
 			arr[3] = sbuff[13];    /* ascq */
 			len = 8;
+		} else {
+			memset(arr, 0, 18);
+			arr[0] = 0x70;
+			arr[2] = sbuff[1];
+			arr[7] = 0xa;
+			arr[12] = sbuff[1];
+			arr[13] = sbuff[3];
 		}
+
 	}
 	mk_sense_buffer(scp, 0, NO_ADDITIONAL_SENSE, 0);
 	return fill_from_dev_buffer(scp, arr, len);
@@ -1181,11 +1430,8 @@
 			   struct sdebug_dev_info * devip)
 {
 	unsigned char *cmd = scp->cmnd;
-	int power_cond, errsts, start;
+	int power_cond, start;
 
-	errsts = check_readiness(scp, UAS_ONLY, devip);
-	if (errsts)
-		return errsts;
 	power_cond = (cmd[4] & 0xf0) >> 4;
 	if (power_cond) {
 		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, 7);
@@ -1212,11 +1458,7 @@
 {
 	unsigned char arr[SDEBUG_READCAP_ARR_SZ];
 	unsigned int capac;
-	int errsts;
 
-	errsts = check_readiness(scp, UAS_ONLY, devip);
-	if (errsts)
-		return errsts;
 	/* following just in case virtual_gb changed */
 	sdebug_capacity = get_sdebug_capacity();
 	memset(arr, 0, SDEBUG_READCAP_ARR_SZ);
@@ -1244,11 +1486,8 @@
 	unsigned char *cmd = scp->cmnd;
 	unsigned char arr[SDEBUG_READCAP16_ARR_SZ];
 	unsigned long long capac;
-	int errsts, k, alloc_len;
+	int k, alloc_len;
 
-	errsts = check_readiness(scp, UAS_ONLY, devip);
-	if (errsts)
-		return errsts;
 	alloc_len = ((cmd[10] << 24) + (cmd[11] << 16) + (cmd[12] << 8)
 		     + cmd[13]);
 	/* following just in case virtual_gb changed */
@@ -1523,20 +1762,18 @@
 
 #define SDEBUG_MAX_MSENSE_SZ 256
 
-static int resp_mode_sense(struct scsi_cmnd * scp, int target,
-			   struct sdebug_dev_info * devip)
+static int
+resp_mode_sense(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
 	unsigned char dbd, llbaa;
 	int pcontrol, pcode, subpcode, bd_len;
 	unsigned char dev_spec;
-	int k, alloc_len, msense_6, offset, len, errsts, target_dev_id;
+	int k, alloc_len, msense_6, offset, len, target_dev_id;
+	int target = scp->device->id;
 	unsigned char * ap;
 	unsigned char arr[SDEBUG_MAX_MSENSE_SZ];
 	unsigned char *cmd = scp->cmnd;
 
-	errsts = check_readiness(scp, UAS_ONLY, devip);
-	if (errsts)
-		return errsts;
 	dbd = !!(cmd[1] & 0x8);
 	pcontrol = (cmd[2] & 0xc0) >> 6;
 	pcode = cmd[2] & 0x3f;
@@ -1684,17 +1921,15 @@
 
 #define SDEBUG_MAX_MSELECT_SZ 512
 
-static int resp_mode_select(struct scsi_cmnd * scp, int mselect6,
-			    struct sdebug_dev_info * devip)
+static int
+resp_mode_select(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
 	int pf, sp, ps, md_len, bd_len, off, spf, pg_len;
-	int param_len, res, errsts, mpage;
+	int param_len, res, mpage;
 	unsigned char arr[SDEBUG_MAX_MSELECT_SZ];
 	unsigned char *cmd = scp->cmnd;
+	int mselect6 = (MODE_SELECT == cmd[0]);
 
-	errsts = check_readiness(scp, UAS_ONLY, devip);
-	if (errsts)
-		return errsts;
 	memset(arr, 0, sizeof(arr));
 	pf = cmd[1] & 0x10;
 	sp = cmd[1] & 0x1;
@@ -1793,13 +2028,10 @@
 static int resp_log_sense(struct scsi_cmnd * scp,
                           struct sdebug_dev_info * devip)
 {
-	int ppc, sp, pcontrol, pcode, subpcode, alloc_len, errsts, len, n;
+	int ppc, sp, pcontrol, pcode, subpcode, alloc_len, len, n;
 	unsigned char arr[SDEBUG_MAX_LSENSE_SZ];
 	unsigned char *cmd = scp->cmnd;
 
-	errsts = check_readiness(scp, UAS_ONLY, devip);
-	if (errsts)
-		return errsts;
 	memset(arr, 0, sizeof(arr));
 	ppc = cmd[1] & 0x2;
 	sp = cmd[1] & 0x1;
@@ -1889,17 +2121,17 @@
 }
 
 /* Returns number of bytes copied or -1 if error. */
-static int do_device_access(struct scsi_cmnd *scmd,
-			    unsigned long long lba, unsigned int num, int write)
+static int
+do_device_access(struct scsi_cmnd *scmd, u64 lba, u32 num, bool do_write)
 {
 	int ret;
-	unsigned long long block, rest = 0;
+	u64 block, rest = 0;
 	struct scsi_data_buffer *sdb;
 	enum dma_data_direction dir;
 	size_t (*func)(struct scatterlist *, unsigned int, void *, size_t,
 		       off_t);
 
-	if (write) {
+	if (do_write) {
 		sdb = scsi_out(scmd);
 		dir = DMA_TO_DEVICE;
 		func = sg_pcopy_to_buffer;
@@ -2045,55 +2277,143 @@
 	return 0;
 }
 
-static int resp_read(struct scsi_cmnd *SCpnt, unsigned long long lba,
-		     unsigned int num, u32 ei_lba)
+static int
+resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
+	u8 *cmd = scp->cmnd;
+	u64 lba;
+	u32 num;
+	u32 ei_lba;
 	unsigned long iflags;
 	int ret;
+	bool check_prot;
 
-	ret = check_device_access_params(SCpnt, lba, num);
-	if (ret)
-		return ret;
+	switch (cmd[0]) {
+	case READ_16:
+		ei_lba = 0;
+		lba = get_unaligned_be64(cmd + 2);
+		num = get_unaligned_be32(cmd + 10);
+		check_prot = true;
+		break;
+	case READ_10:
+		ei_lba = 0;
+		lba = get_unaligned_be32(cmd + 2);
+		num = get_unaligned_be16(cmd + 7);
+		check_prot = true;
+		break;
+	case READ_6:
+		ei_lba = 0;
+		lba = (u32)cmd[3] | (u32)cmd[2] << 8 |
+		      (u32)(cmd[1] & 0x1f) << 16;
+		num = (0 == cmd[4]) ? 256 : cmd[4];
+		check_prot = true;
+		break;
+	case READ_12:
+		ei_lba = 0;
+		lba = get_unaligned_be32(cmd + 2);
+		num = get_unaligned_be32(cmd + 6);
+		check_prot = true;
+		break;
+	case XDWRITEREAD_10:
+		ei_lba = 0;
+		lba = get_unaligned_be32(cmd + 2);
+		num = get_unaligned_be16(cmd + 7);
+		check_prot = false;
+		break;
+	default:	/* assume READ(32) */
+		lba = get_unaligned_be64(cmd + 12);
+		ei_lba = get_unaligned_be32(cmd + 20);
+		num = get_unaligned_be32(cmd + 28);
+		check_prot = false;
+		break;
+	}
+	if (check_prot) {
+		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
+		    (cmd[1] & 0xe0)) {
+			mk_sense_invalid_opcode(scp);
+			return check_condition_result;
+		}
+		if ((scsi_debug_dif == SD_DIF_TYPE1_PROTECTION ||
+		     scsi_debug_dif == SD_DIF_TYPE3_PROTECTION) &&
+		    (cmd[1] & 0xe0) == 0)
+			sdev_printk(KERN_ERR, scp->device, "Unprotected RD "
+				    "to DIF device\n");
+	}
+	if (sdebug_any_injecting_opt) {
+		struct sdebug_scmd_extra_t *ep = scsi_cmd_priv(scp);
+
+		if (ep->inj_short)
+			num /= 2;
+	}
+
+	/* 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;
+	}
 
 	if ((SCSI_DEBUG_OPT_MEDIUM_ERR & scsi_debug_opts) &&
 	    (lba <= (OPT_MEDIUM_ERR_ADDR + OPT_MEDIUM_ERR_NUM - 1)) &&
 	    ((lba + num) > OPT_MEDIUM_ERR_ADDR)) {
 		/* claim unrecoverable read error */
-		mk_sense_buffer(SCpnt, MEDIUM_ERROR, UNRECOVERED_READ_ERR, 0);
+		mk_sense_buffer(scp, MEDIUM_ERROR, UNRECOVERED_READ_ERR, 0);
 		/* set info field and valid bit for fixed descriptor */
-		if (0x70 == (SCpnt->sense_buffer[0] & 0x7f)) {
-			SCpnt->sense_buffer[0] |= 0x80;	/* Valid bit */
+		if (0x70 == (scp->sense_buffer[0] & 0x7f)) {
+			scp->sense_buffer[0] |= 0x80;	/* Valid bit */
 			ret = (lba < OPT_MEDIUM_ERR_ADDR)
 			      ? OPT_MEDIUM_ERR_ADDR : (int)lba;
-			SCpnt->sense_buffer[3] = (ret >> 24) & 0xff;
-			SCpnt->sense_buffer[4] = (ret >> 16) & 0xff;
-			SCpnt->sense_buffer[5] = (ret >> 8) & 0xff;
-			SCpnt->sense_buffer[6] = ret & 0xff;
+			put_unaligned_be32(ret, scp->sense_buffer + 3);
 		}
-	        scsi_set_resid(SCpnt, scsi_bufflen(SCpnt));
+		scsi_set_resid(scp, scsi_bufflen(scp));
 		return check_condition_result;
 	}
 
 	read_lock_irqsave(&atomic_rw, iflags);
 
 	/* DIX + T10 DIF */
-	if (scsi_debug_dix && scsi_prot_sg_count(SCpnt)) {
-		int prot_ret = prot_verify_read(SCpnt, lba, num, ei_lba);
+	if (scsi_debug_dix && scsi_prot_sg_count(scp)) {
+		int prot_ret = prot_verify_read(scp, lba, num, ei_lba);
 
 		if (prot_ret) {
 			read_unlock_irqrestore(&atomic_rw, iflags);
-			mk_sense_buffer(SCpnt, ABORTED_COMMAND, 0x10, prot_ret);
+			mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, prot_ret);
 			return illegal_condition_result;
 		}
 	}
 
-	ret = do_device_access(SCpnt, lba, num, 0);
+	ret = do_device_access(scp, lba, num, false);
 	read_unlock_irqrestore(&atomic_rw, iflags);
 	if (ret == -1)
 		return DID_ERROR << 16;
 
-	scsi_in(SCpnt)->resid = scsi_bufflen(SCpnt) - ret;
+	scsi_in(scp)->resid = scsi_bufflen(scp) - ret;
 
+	if (sdebug_any_injecting_opt) {
+		struct sdebug_scmd_extra_t *ep = scsi_cmd_priv(scp);
+
+		if (ep->inj_recovered) {
+			mk_sense_buffer(scp, RECOVERED_ERROR,
+					THRESHOLD_EXCEEDED, 0);
+			return check_condition_result;
+		} else if (ep->inj_transport) {
+			mk_sense_buffer(scp, ABORTED_COMMAND,
+					TRANSPORT_PROBLEM, ACK_NAK_TO);
+			return check_condition_result;
+		} else if (ep->inj_dif) {
+			/* Logical block guard check failed */
+			mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
+			return illegal_condition_result;
+		} else if (ep->inj_dix) {
+			mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
+			return illegal_condition_result;
+		}
+	}
 	return 0;
 }
 
@@ -2276,31 +2596,95 @@
 	}
 }
 
-static int resp_write(struct scsi_cmnd *SCpnt, unsigned long long lba,
-		      unsigned int num, u32 ei_lba)
+static int
+resp_write_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
+	u8 *cmd = scp->cmnd;
+	u64 lba;
+	u32 num;
+	u32 ei_lba;
 	unsigned long iflags;
 	int ret;
+	bool check_prot;
 
-	ret = check_device_access_params(SCpnt, lba, num);
-	if (ret)
-		return ret;
+	switch (cmd[0]) {
+	case WRITE_16:
+		ei_lba = 0;
+		lba = get_unaligned_be64(cmd + 2);
+		num = get_unaligned_be32(cmd + 10);
+		check_prot = true;
+		break;
+	case WRITE_10:
+		ei_lba = 0;
+		lba = get_unaligned_be32(cmd + 2);
+		num = get_unaligned_be16(cmd + 7);
+		check_prot = true;
+		break;
+	case WRITE_6:
+		ei_lba = 0;
+		lba = (u32)cmd[3] | (u32)cmd[2] << 8 |
+		      (u32)(cmd[1] & 0x1f) << 16;
+		num = (0 == cmd[4]) ? 256 : cmd[4];
+		check_prot = true;
+		break;
+	case WRITE_12:
+		ei_lba = 0;
+		lba = get_unaligned_be32(cmd + 2);
+		num = get_unaligned_be32(cmd + 6);
+		check_prot = true;
+		break;
+	case 0x53:	/* XDWRITEREAD(10) */
+		ei_lba = 0;
+		lba = get_unaligned_be32(cmd + 2);
+		num = get_unaligned_be16(cmd + 7);
+		check_prot = false;
+		break;
+	default:	/* assume WRITE(32) */
+		lba = get_unaligned_be64(cmd + 12);
+		ei_lba = get_unaligned_be32(cmd + 20);
+		num = get_unaligned_be32(cmd + 28);
+		check_prot = false;
+		break;
+	}
+	if (check_prot) {
+		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
+		    (cmd[1] & 0xe0)) {
+			mk_sense_invalid_opcode(scp);
+			return check_condition_result;
+		}
+		if ((scsi_debug_dif == SD_DIF_TYPE1_PROTECTION ||
+		     scsi_debug_dif == SD_DIF_TYPE3_PROTECTION) &&
+		    (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;
+	}
 
 	write_lock_irqsave(&atomic_rw, iflags);
 
 	/* DIX + T10 DIF */
-	if (scsi_debug_dix && scsi_prot_sg_count(SCpnt)) {
-		int prot_ret = prot_verify_write(SCpnt, lba, num, ei_lba);
+	if (scsi_debug_dix && scsi_prot_sg_count(scp)) {
+		int prot_ret = prot_verify_write(scp, lba, num, ei_lba);
 
 		if (prot_ret) {
 			write_unlock_irqrestore(&atomic_rw, iflags);
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST, 0x10,
-					prot_ret);
+			mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, prot_ret);
 			return illegal_condition_result;
 		}
 	}
 
-	ret = do_device_access(SCpnt, lba, num, 1);
+	ret = do_device_access(scp, lba, num, true);
 	if (scsi_debug_lbp())
 		map_region(lba, num);
 	write_unlock_irqrestore(&atomic_rw, iflags);
@@ -2308,30 +2692,41 @@
 		return (DID_ERROR << 16);
 	else if ((ret < (num * scsi_debug_sector_size)) &&
 		 (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts))
-		sdev_printk(KERN_INFO, SCpnt->device,
+		sdev_printk(KERN_INFO, scp->device,
 			    "%s: write: cdb indicated=%u, IO sent=%d bytes\n",
 			    my_name, num * scsi_debug_sector_size, ret);
 
+	if (sdebug_any_injecting_opt) {
+		struct sdebug_scmd_extra_t *ep = scsi_cmd_priv(scp);
+
+		if (ep->inj_recovered) {
+			mk_sense_buffer(scp, RECOVERED_ERROR,
+					THRESHOLD_EXCEEDED, 0);
+			return check_condition_result;
+		} else if (ep->inj_dif) {
+			/* Logical block guard check failed */
+			mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
+			return illegal_condition_result;
+		} else if (ep->inj_dix) {
+			mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
+			return illegal_condition_result;
+		}
+	}
 	return 0;
 }
 
-static int resp_write_same(struct scsi_cmnd *scmd, unsigned long long lba,
-		      unsigned int num, u32 ei_lba, unsigned int unmap)
+static int
+resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num, u32 ei_lba,
+		bool unmap, bool ndob)
 {
 	unsigned long iflags;
 	unsigned long long i;
 	int ret;
 
-	ret = check_device_access_params(scmd, lba, num);
+	ret = check_device_access_params(scp, lba, num);
 	if (ret)
 		return ret;
 
-	if (num > scsi_debug_write_same_length) {
-		mk_sense_buffer(scmd, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
-				0);
-		return check_condition_result;
-	}
-
 	write_lock_irqsave(&atomic_rw, iflags);
 
 	if (unmap && scsi_debug_lbp()) {
@@ -2339,17 +2734,22 @@
 		goto out;
 	}
 
-	/* Else fetch one logical block */
-	ret = fetch_to_dev_buffer(scmd,
-				  fake_storep + (lba * scsi_debug_sector_size),
-				  scsi_debug_sector_size);
+	/* if ndob then zero 1 logical block, else fetch 1 logical block */
+	if (ndob) {
+		memset(fake_storep + (lba * scsi_debug_sector_size), 0,
+		       scsi_debug_sector_size);
+		ret = 0;
+	} else
+		ret = fetch_to_dev_buffer(scp, fake_storep +
+					       (lba * scsi_debug_sector_size),
+					  scsi_debug_sector_size);
 
 	if (-1 == ret) {
 		write_unlock_irqrestore(&atomic_rw, iflags);
 		return (DID_ERROR << 16);
 	} else if ((ret < (num * scsi_debug_sector_size)) &&
 		 (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts))
-		sdev_printk(KERN_INFO, scmd->device,
+		sdev_printk(KERN_INFO, scp->device,
 			    "%s: %s: cdb indicated=%u, IO sent=%d bytes\n",
 			    my_name, "write same",
 			    num * scsi_debug_sector_size, ret);
@@ -2368,13 +2768,67 @@
 	return 0;
 }
 
+static int
+resp_write_same_10(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	u32 lba;
+	u16 num;
+	u32 ei_lba = 0;
+	bool unmap = false;
+
+	if (cmd[1] & 0x8) {
+		if (scsi_debug_lbpws10 == 0) {
+			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 3);
+			return check_condition_result;
+		} else
+			unmap = true;
+	}
+	lba = get_unaligned_be32(cmd + 2);
+	num = get_unaligned_be16(cmd + 7);
+	if (num > scsi_debug_write_same_length) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 7, -1);
+		return check_condition_result;
+	}
+	return resp_write_same(scp, lba, num, ei_lba, unmap, false);
+}
+
+static int
+resp_write_same_16(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	u64 lba;
+	u32 num;
+	u32 ei_lba = 0;
+	bool unmap = false;
+	bool ndob = false;
+
+	if (cmd[1] & 0x8) {	/* UNMAP */
+		if (scsi_debug_lbpws == 0) {
+			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 3);
+			return check_condition_result;
+		} else
+			unmap = true;
+	}
+	if (cmd[1] & 0x1)  /* NDOB (no data-out buffer, assumes zeroes) */
+		ndob = true;
+	lba = get_unaligned_be64(cmd + 2);
+	num = get_unaligned_be32(cmd + 10);
+	if (num > scsi_debug_write_same_length) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 10, -1);
+		return check_condition_result;
+	}
+	return resp_write_same(scp, lba, num, ei_lba, unmap, ndob);
+}
+
 struct unmap_block_desc {
 	__be64	lba;
 	__be32	blocks;
 	__be32	__reserved;
 };
 
-static int resp_unmap(struct scsi_cmnd * scmd, struct sdebug_dev_info * devip)
+static int
+resp_unmap(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
 	unsigned char *buf;
 	struct unmap_block_desc *desc;
@@ -2382,20 +2836,26 @@
 	int ret;
 	unsigned long iflags;
 
-	ret = check_readiness(scmd, UAS_ONLY, devip);
-	if (ret)
-		return ret;
 
-	payload_len = get_unaligned_be16(&scmd->cmnd[7]);
-	BUG_ON(scsi_bufflen(scmd) != payload_len);
+	if (!scsi_debug_lbp())
+		return 0;	/* fib and say its done */
+	payload_len = get_unaligned_be16(scp->cmnd + 7);
+	BUG_ON(scsi_bufflen(scp) != payload_len);
 
 	descriptors = (payload_len - 8) / 16;
-
-	buf = kmalloc(scsi_bufflen(scmd), GFP_ATOMIC);
-	if (!buf)
+	if (descriptors > scsi_debug_unmap_max_desc) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 7, -1);
 		return check_condition_result;
+	}
 
-	scsi_sg_copy_to_buffer(scmd, buf, scsi_bufflen(scmd));
+	buf = kmalloc(scsi_bufflen(scp), GFP_ATOMIC);
+	if (!buf) {
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
+				INSUFF_RES_ASCQ);
+		return check_condition_result;
+	}
+
+	scsi_sg_copy_to_buffer(scp, buf, scsi_bufflen(scp));
 
 	BUG_ON(get_unaligned_be16(&buf[0]) != payload_len - 2);
 	BUG_ON(get_unaligned_be16(&buf[2]) != descriptors * 16);
@@ -2408,7 +2868,7 @@
 		unsigned long long lba = get_unaligned_be64(&desc[i].lba);
 		unsigned int num = get_unaligned_be32(&desc[i].blocks);
 
-		ret = check_device_access_params(scmd, lba, num);
+		ret = check_device_access_params(scp, lba, num);
 		if (ret)
 			goto out;
 
@@ -2426,37 +2886,44 @@
 
 #define SDEBUG_GET_LBA_STATUS_LEN 32
 
-static int resp_get_lba_status(struct scsi_cmnd * scmd,
-			       struct sdebug_dev_info * devip)
+static int
+resp_get_lba_status(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
 {
-	unsigned long long lba;
-	unsigned int alloc_len, mapped, num;
-	unsigned char arr[SDEBUG_GET_LBA_STATUS_LEN];
+	u8 *cmd = scp->cmnd;
+	u64 lba;
+	u32 alloc_len, mapped, num;
+	u8 arr[SDEBUG_GET_LBA_STATUS_LEN];
 	int ret;
 
-	ret = check_readiness(scmd, UAS_ONLY, devip);
-	if (ret)
-		return ret;
-
-	lba = get_unaligned_be64(&scmd->cmnd[2]);
-	alloc_len = get_unaligned_be32(&scmd->cmnd[10]);
+	lba = get_unaligned_be64(cmd + 2);
+	alloc_len = get_unaligned_be32(cmd + 10);
 
 	if (alloc_len < 24)
 		return 0;
 
-	ret = check_device_access_params(scmd, lba, 1);
+	ret = check_device_access_params(scp, lba, 1);
 	if (ret)
 		return ret;
 
-	mapped = map_state(lba, &num);
+	if (scsi_debug_lbp())
+		mapped = map_state(lba, &num);
+	else {
+		mapped = 1;
+		/* following just in case virtual_gb changed */
+		sdebug_capacity = get_sdebug_capacity();
+		if (sdebug_capacity - lba <= 0xffffffff)
+			num = sdebug_capacity - lba;
+		else
+			num = 0xffffffff;
+	}
 
 	memset(arr, 0, SDEBUG_GET_LBA_STATUS_LEN);
-	put_unaligned_be32(20, &arr[0]);	/* Parameter Data Length */
-	put_unaligned_be64(lba, &arr[8]);	/* LBA */
-	put_unaligned_be32(num, &arr[16]);	/* Number of blocks */
-	arr[20] = !mapped;			/* mapped = 0, unmapped = 1 */
+	put_unaligned_be32(20, arr);		/* Parameter Data Length */
+	put_unaligned_be64(lba, arr + 8);	/* LBA */
+	put_unaligned_be32(num, arr + 16);	/* Number of blocks */
+	arr[20] = !mapped;		/* prov_stat=0: mapped; 1: dealloc */
 
-	return fill_from_dev_buffer(scmd, arr, SDEBUG_GET_LBA_STATUS_LEN);
+	return fill_from_dev_buffer(scp, arr, SDEBUG_GET_LBA_STATUS_LEN);
 }
 
 #define SDEBUG_RLUN_ARR_SZ 256
@@ -2553,6 +3020,32 @@
 	return 0;
 }
 
+static int
+resp_xdwriteread_10(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	u64 lba;
+	u32 num;
+	int errsts;
+
+	if (!scsi_bidi_cmnd(scp)) {
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
+				INSUFF_RES_ASCQ);
+		return check_condition_result;
+	}
+	errsts = resp_read_dt0(scp, devip);
+	if (errsts)
+		return errsts;
+	if (!(cmd[1] & 0x4)) {		/* DISABLE_WRITE is not set */
+		errsts = resp_write_dt0(scp, devip);
+		if (errsts)
+			return errsts;
+	}
+	lba = get_unaligned_be32(cmd + 2);
+	num = get_unaligned_be16(cmd + 7);
+	return resp_xdwriteread(scp, lba, num, devip);
+}
+
 /* When timer or tasklet goes off this function is called. */
 static void sdebug_q_cmd_complete(unsigned long indx)
 {
@@ -2725,10 +3218,7 @@
 	open_devip->sdbg_host = sdbg_host;
 	atomic_set(&open_devip->num_in_q, 0);
 	set_bit(SDEBUG_UA_POR, open_devip->uas_bm);
-	open_devip->used = 1;
-	if (sdev->lun == SAM2_WLUN_REPORT_LUNS)
-		open_devip->wlun = SAM2_WLUN_REPORT_LUNS & 0xff;
-
+	open_devip->used = true;
 	return open_devip;
 }
 
@@ -2770,7 +3260,7 @@
 		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
 	if (devip) {
 		/* make this slot available for re-use */
-		devip->used = 0;
+		devip->used = false;
 		sdp->hostdata = NULL;
 	}
 }
@@ -3215,6 +3705,7 @@
 module_param_named(removable, scsi_debug_removable, bool, S_IRUGO | S_IWUSR);
 module_param_named(scsi_level, scsi_debug_scsi_level, int, S_IRUGO);
 module_param_named(sector_size, scsi_debug_sector_size, int, S_IRUGO);
+module_param_named(strict, scsi_debug_strict, bool, S_IRUGO | S_IWUSR);
 module_param_named(unmap_alignment, scsi_debug_unmap_alignment, int, S_IRUGO);
 module_param_named(unmap_granularity, scsi_debug_unmap_granularity, int, S_IRUGO);
 module_param_named(unmap_max_blocks, scsi_debug_unmap_max_blocks, int, S_IRUGO);
@@ -3234,7 +3725,7 @@
 MODULE_PARM_DESC(ato, "application tag ownership: 0=disk 1=host (def=1)");
 MODULE_PARM_DESC(clustering, "when set enables larger transfers (def=0)");
 MODULE_PARM_DESC(delay, "response delay (def=1 jiffy); 0:imm, -1,-2:tiny");
-MODULE_PARM_DESC(dev_size_mb, "size in MB of ram shared by devs(def=8)");
+MODULE_PARM_DESC(dev_size_mb, "size in MiB of ram shared by devs(def=8)");
 MODULE_PARM_DESC(dif, "data integrity field type: 0-3 (def=0)");
 MODULE_PARM_DESC(dix, "data integrity extensions mask (def=0)");
 MODULE_PARM_DESC(dsense, "use descriptor sense format(def=0 -> fixed)");
@@ -3261,11 +3752,12 @@
 MODULE_PARM_DESC(removable, "claim to have removable media (def=0)");
 MODULE_PARM_DESC(scsi_level, "SCSI level to simulate(def=6[SPC-4])");
 MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)");
+MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)");
 MODULE_PARM_DESC(unmap_alignment, "lowest aligned thin provisioning lba (def=0)");
 MODULE_PARM_DESC(unmap_granularity, "thin provisioning granularity in blocks (def=1)");
 MODULE_PARM_DESC(unmap_max_blocks, "max # of blocks can be unmapped in one cmd (def=0xffffffff)");
 MODULE_PARM_DESC(unmap_max_desc, "max # of ranges that can be unmapped in one cmd (def=256)");
-MODULE_PARM_DESC(virtual_gb, "virtual gigabyte size (def=0 -> use dev_size_mb)");
+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(write_same_length, "Maximum blocks per WRITE SAME cmd (def=0xffff)");
 
@@ -3644,11 +4136,10 @@
 {
         return scnprintf(buf, PAGE_SIZE, "%d\n", scsi_debug_virtual_gb);
 }
-
 static ssize_t virtual_gb_store(struct device_driver *ddp, const char *buf,
 				size_t count)
 {
-	int n;
+        int n;
 	bool changed;
 
 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
@@ -3813,6 +4304,23 @@
 }
 static DRIVER_ATTR_RW(host_lock);
 
+static ssize_t strict_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!scsi_debug_strict);
+}
+static ssize_t strict_store(struct device_driver *ddp, const char *buf,
+			    size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		scsi_debug_strict = (n > 0);
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(strict);
+
 
 /* Note: The following array creates attribute files in the
    /sys/bus/pseudo/drivers/scsi_debug directory. The advantage of these
@@ -3848,6 +4356,7 @@
 	&driver_attr_removable.attr,
 	&driver_attr_host_lock.attr,
 	&driver_attr_ndelay.attr,
+	&driver_attr_strict.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(sdebug_drv);
@@ -4160,377 +4669,6 @@
 }
 
 static int
-scsi_debug_queuecommand(struct scsi_cmnd *SCpnt)
-{
-	unsigned char *cmd = SCpnt->cmnd;
-	int len, k;
-	unsigned int num;
-	unsigned long long lba;
-	u32 ei_lba;
-	int errsts = 0;
-	int target = SCpnt->device->id;
-	struct sdebug_dev_info *devip = NULL;
-	int inj_recovered = 0;
-	int inj_transport = 0;
-	int inj_dif = 0;
-	int inj_dix = 0;
-	int inj_short = 0;
-	int delay_override = 0;
-	int unmap = 0;
-
-	scsi_set_resid(SCpnt, 0);
-	if ((SCSI_DEBUG_OPT_NOISE & scsi_debug_opts) &&
-	    !(SCSI_DEBUG_OPT_NO_CDB_NOISE & scsi_debug_opts)) {
-		char b[120];
-		int n;
-
-		len = SCpnt->cmd_len;
-		if (len > 32)
-			strcpy(b, "too long, over 32 bytes");
-		else {
-			for (k = 0, n = 0; k < len; ++k)
-				n += scnprintf(b + n, sizeof(b) - n, "%02x ",
-					       (unsigned int)cmd[k]);
-		}
-		sdev_printk(KERN_INFO, SCpnt->device, "%s: cmd %s\n", my_name,
-			    b);
-	}
-
-	if ((SCpnt->device->lun >= scsi_debug_max_luns) &&
-	    (SCpnt->device->lun != SAM2_WLUN_REPORT_LUNS))
-		return schedule_resp(SCpnt, NULL, DID_NO_CONNECT << 16, 0);
-	devip = devInfoReg(SCpnt->device);
-	if (NULL == devip)
-		return schedule_resp(SCpnt, NULL, DID_NO_CONNECT << 16, 0);
-
-	if ((scsi_debug_every_nth != 0) &&
-	    (atomic_inc_return(&sdebug_cmnd_count) >=
-	     abs(scsi_debug_every_nth))) {
-		atomic_set(&sdebug_cmnd_count, 0);
-		if (scsi_debug_every_nth < -1)
-			scsi_debug_every_nth = -1;
-		if (SCSI_DEBUG_OPT_TIMEOUT & scsi_debug_opts)
-			return 0; /* ignore command causing timeout */
-		else if (SCSI_DEBUG_OPT_MAC_TIMEOUT & scsi_debug_opts &&
-			 scsi_medium_access_command(SCpnt))
-			return 0; /* time out reads and writes */
-		else if (SCSI_DEBUG_OPT_RECOVERED_ERR & scsi_debug_opts)
-			inj_recovered = 1; /* to reads and writes below */
-		else if (SCSI_DEBUG_OPT_TRANSPORT_ERR & scsi_debug_opts)
-			inj_transport = 1; /* to reads and writes below */
-		else if (SCSI_DEBUG_OPT_DIF_ERR & scsi_debug_opts)
-			inj_dif = 1; /* to reads and writes below */
-		else if (SCSI_DEBUG_OPT_DIX_ERR & scsi_debug_opts)
-			inj_dix = 1; /* to reads and writes below */
-		else if (SCSI_DEBUG_OPT_SHORT_TRANSFER & scsi_debug_opts)
-			inj_short = 1;
-	}
-
-	if (devip->wlun) {
-		switch (*cmd) {
-		case INQUIRY:
-		case REQUEST_SENSE:
-		case TEST_UNIT_READY:
-		case REPORT_LUNS:
-			break;  /* only allowable wlun commands */
-		default:
-			if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-				printk(KERN_INFO "scsi_debug: Opcode: 0x%x "
-				       "not supported for wlun\n", *cmd);
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_OPCODE, 0);
-			errsts = check_condition_result;
-			return schedule_resp(SCpnt, devip, errsts, 0);
-		}
-	}
-
-	switch (*cmd) {
-	case INQUIRY:     /* mandatory, ignore unit attention */
-		delay_override = 1;
-		errsts = resp_inquiry(SCpnt, target, devip);
-		break;
-	case REQUEST_SENSE:	/* mandatory, ignore unit attention */
-		delay_override = 1;
-		errsts = resp_requests(SCpnt, devip);
-		break;
-	case REZERO_UNIT:	/* actually this is REWIND for SSC */
-	case START_STOP:
-		errsts = resp_start_stop(SCpnt, devip);
-		break;
-	case ALLOW_MEDIUM_REMOVAL:
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		if (errsts)
-			break;
-		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-			printk(KERN_INFO "scsi_debug: Medium removal %s\n",
-			       cmd[4] ? "inhibited" : "enabled");
-		break;
-	case SEND_DIAGNOSTIC:     /* mandatory */
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		break;
-	case TEST_UNIT_READY:     /* mandatory */
-		/* delay_override = 1; */
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		break;
-	case RESERVE:
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		break;
-	case RESERVE_10:
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		break;
-	case RELEASE:
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		break;
-	case RELEASE_10:
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		break;
-	case READ_CAPACITY:
-		errsts = resp_readcap(SCpnt, devip);
-		break;
-	case SERVICE_ACTION_IN:
-		if (cmd[1] == SAI_READ_CAPACITY_16)
-			errsts = resp_readcap16(SCpnt, devip);
-		else if (cmd[1] == SAI_GET_LBA_STATUS) {
-
-			if (scsi_debug_lbp() == 0) {
-				mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-						INVALID_COMMAND_OPCODE, 0);
-				errsts = check_condition_result;
-			} else
-				errsts = resp_get_lba_status(SCpnt, devip);
-		} else {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_OPCODE, 0);
-			errsts = check_condition_result;
-		}
-		break;
-	case MAINTENANCE_IN:
-		if (MI_REPORT_TARGET_PGS != cmd[1]) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_OPCODE, 0);
-			errsts = check_condition_result;
-			break;
-		}
-		errsts = resp_report_tgtpgs(SCpnt, devip);
-		break;
-	case READ_16:
-	case READ_12:
-	case READ_10:
-		/* READ{10,12,16} and DIF Type 2 are natural enemies */
-		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
-		    cmd[1] & 0xe0) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_COMMAND_OPCODE, 0);
-			errsts = check_condition_result;
-			break;
-		}
-
-		if ((scsi_debug_dif == SD_DIF_TYPE1_PROTECTION ||
-		     scsi_debug_dif == SD_DIF_TYPE3_PROTECTION) &&
-		    (cmd[1] & 0xe0) == 0)
-			printk(KERN_ERR "Unprotected RD/WR to DIF device\n");
-
-		/* fall through */
-	case READ_6:
-read:
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		if (errsts)
-			break;
-		if (scsi_debug_fake_rw)
-			break;
-		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
-
-		if (inj_short)
-			num /= 2;
-
-		errsts = resp_read(SCpnt, lba, num, ei_lba);
-		if (inj_recovered && (0 == errsts)) {
-			mk_sense_buffer(SCpnt, RECOVERED_ERROR,
-					THRESHOLD_EXCEEDED, 0);
-			errsts = check_condition_result;
-		} else if (inj_transport && (0 == errsts)) {
-			mk_sense_buffer(SCpnt, ABORTED_COMMAND,
-					TRANSPORT_PROBLEM, ACK_NAK_TO);
-			errsts = check_condition_result;
-		} else if (inj_dif && (0 == errsts)) {
-			/* Logical block guard check failed */
-			mk_sense_buffer(SCpnt, ABORTED_COMMAND, 0x10, 1);
-			errsts = illegal_condition_result;
-		} else if (inj_dix && (0 == errsts)) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST, 0x10, 1);
-			errsts = illegal_condition_result;
-		}
-		break;
-	case REPORT_LUNS:	/* mandatory, ignore unit attention */
-		delay_override = 1;
-		errsts = resp_report_luns(SCpnt, devip);
-		break;
-	case VERIFY:		/* 10 byte SBC-2 command */
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		break;
-	case WRITE_16:
-	case WRITE_12:
-	case WRITE_10:
-		/* WRITE{10,12,16} and DIF Type 2 are natural enemies */
-		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION &&
-		    cmd[1] & 0xe0) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_COMMAND_OPCODE, 0);
-			errsts = check_condition_result;
-			break;
-		}
-
-		if ((scsi_debug_dif == SD_DIF_TYPE1_PROTECTION ||
-		     scsi_debug_dif == SD_DIF_TYPE3_PROTECTION) &&
-		    (cmd[1] & 0xe0) == 0)
-			printk(KERN_ERR "Unprotected RD/WR to DIF device\n");
-
-		/* fall through */
-	case WRITE_6:
-write:
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		if (errsts)
-			break;
-		if (scsi_debug_fake_rw)
-			break;
-		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
-		errsts = resp_write(SCpnt, lba, num, ei_lba);
-		if (inj_recovered && (0 == errsts)) {
-			mk_sense_buffer(SCpnt, RECOVERED_ERROR,
-					THRESHOLD_EXCEEDED, 0);
-			errsts = check_condition_result;
-		} else if (inj_dif && (0 == errsts)) {
-			mk_sense_buffer(SCpnt, ABORTED_COMMAND, 0x10, 1);
-			errsts = illegal_condition_result;
-		} else if (inj_dix && (0 == errsts)) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST, 0x10, 1);
-			errsts = illegal_condition_result;
-		}
-		break;
-	case WRITE_SAME_16:
-	case WRITE_SAME:
-		if (cmd[1] & 0x8) {
-			if ((*cmd == WRITE_SAME_16 && scsi_debug_lbpws == 0) ||
-			    (*cmd == WRITE_SAME && scsi_debug_lbpws10 == 0)) {
-				mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-						INVALID_FIELD_IN_CDB, 0);
-				errsts = check_condition_result;
-			} else
-				unmap = 1;
-		}
-		if (errsts)
-			break;
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		if (errsts)
-			break;
-		if (scsi_debug_fake_rw)
-			break;
-		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
-		errsts = resp_write_same(SCpnt, lba, num, ei_lba, unmap);
-		break;
-	case UNMAP:
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		if (errsts)
-			break;
-		if (scsi_debug_fake_rw)
-			break;
-
-		if (scsi_debug_unmap_max_desc == 0 || scsi_debug_lbpu == 0) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_COMMAND_OPCODE, 0);
-			errsts = check_condition_result;
-		} else
-			errsts = resp_unmap(SCpnt, devip);
-		break;
-	case MODE_SENSE:
-	case MODE_SENSE_10:
-		errsts = resp_mode_sense(SCpnt, target, devip);
-		break;
-	case MODE_SELECT:
-		errsts = resp_mode_select(SCpnt, 1, devip);
-		break;
-	case MODE_SELECT_10:
-		errsts = resp_mode_select(SCpnt, 0, devip);
-		break;
-	case LOG_SENSE:
-		errsts = resp_log_sense(SCpnt, devip);
-		break;
-	case SYNCHRONIZE_CACHE:
-		delay_override = 1;
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		break;
-	case WRITE_BUFFER:
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		break;
-	case XDWRITEREAD_10:
-		if (!scsi_bidi_cmnd(SCpnt)) {
-			mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-					INVALID_FIELD_IN_CDB, 0);
-			errsts = check_condition_result;
-			break;
-		}
-
-		errsts = check_readiness(SCpnt, UAS_TUR, devip);
-		if (errsts)
-			break;
-		if (scsi_debug_fake_rw)
-			break;
-		get_data_transfer_info(cmd, &lba, &num, &ei_lba);
-		errsts = resp_read(SCpnt, lba, num, ei_lba);
-		if (errsts)
-			break;
-		errsts = resp_write(SCpnt, lba, num, ei_lba);
-		if (errsts)
-			break;
-		errsts = resp_xdwriteread(SCpnt, lba, num, devip);
-		break;
-	case VARIABLE_LENGTH_CMD:
-		if (scsi_debug_dif == SD_DIF_TYPE2_PROTECTION) {
-
-			if ((cmd[10] & 0xe0) == 0)
-				printk(KERN_ERR
-				       "Unprotected RD/WR to DIF device\n");
-
-			if (cmd[9] == READ_32) {
-				BUG_ON(SCpnt->cmd_len < 32);
-				goto read;
-			}
-
-			if (cmd[9] == WRITE_32) {
-				BUG_ON(SCpnt->cmd_len < 32);
-				goto write;
-			}
-		}
-
-		mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-				INVALID_FIELD_IN_CDB, 0);
-		errsts = check_condition_result;
-		break;
-	case 0x85:
-		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-			sdev_printk(KERN_INFO, SCpnt->device,
-			"%s: ATA PASS-THROUGH(16) not supported\n", my_name);
-		mk_sense_buffer(SCpnt, ILLEGAL_REQUEST,
-				INVALID_OPCODE, 0);
-		errsts = check_condition_result;
-		break;
-	default:
-		if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-			sdev_printk(KERN_INFO, SCpnt->device,
-				    "%s: Opcode: 0x%x not supported\n",
-				    my_name, *cmd);
-		errsts = check_readiness(SCpnt, UAS_ONLY, devip);
-		if (errsts)
-			break;	/* Unit attention takes precedence */
-		mk_sense_buffer(SCpnt, ILLEGAL_REQUEST, INVALID_OPCODE, 0);
-		errsts = check_condition_result;
-		break;
-	}
-	return schedule_resp(SCpnt, devip, errsts,
-			     (delay_override ? 0 : scsi_debug_delay));
-}
-
-static int
 sdebug_queuecommand_lock_or_not(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
 {
 	if (scsi_debug_host_lock) {
@@ -4637,6 +4775,143 @@
 	return 0;
 }
 
+static int
+scsi_debug_queuecommand(struct scsi_cmnd *scp)
+{
+	u8 sdeb_i;
+	struct scsi_device *sdp = scp->device;
+	const struct opcode_info_t *oip;
+	const struct opcode_info_t *r_oip;
+	struct sdebug_dev_info *devip;
+	u8 *cmd = scp->cmnd;
+	int (*r_pfp)(struct scsi_cmnd *, struct sdebug_dev_info *);
+	int k, na;
+	int errsts = 0;
+	int errsts_no_connect = DID_NO_CONNECT << 16;
+	u32 flags;
+	u16 sa;
+	u8 opcode = cmd[0];
+	bool has_wlun_rl;
+	bool debug = !!(SCSI_DEBUG_OPT_NOISE & scsi_debug_opts);
+
+	scsi_set_resid(scp, 0);
+	if (debug && !(SCSI_DEBUG_OPT_NO_CDB_NOISE & scsi_debug_opts)) {
+		char b[120];
+		int n, len, sb;
+
+		len = scp->cmd_len;
+		sb = (int)sizeof(b);
+		if (len > 32)
+			strcpy(b, "too long, over 32 bytes");
+		else {
+			for (k = 0, n = 0; k < len && n < sb; ++k)
+				n += scnprintf(b + n, sb - n, "%02x ",
+					       (u32)cmd[k]);
+		}
+		sdev_printk(KERN_INFO, sdp, "%s: cmd %s\n", my_name, b);
+	}
+	has_wlun_rl = (sdp->lun == SAM2_WLUN_REPORT_LUNS);
+	if ((sdp->lun >= scsi_debug_max_luns) && !has_wlun_rl)
+		return schedule_resp(scp, NULL, errsts_no_connect, 0);
+
+	sdeb_i = opcode_ind_arr[opcode];	/* fully mapped */
+	oip = &opcode_info_arr[sdeb_i];		/* safe if table consistent */
+	devip = (struct sdebug_dev_info *)sdp->hostdata;
+	if (!devip) {
+		devip = devInfoReg(sdp);
+		if (NULL == devip)
+			return schedule_resp(scp, NULL, errsts_no_connect, 0);
+	}
+	na = oip->num_attached;
+	r_pfp = oip->pfp;
+	if (na) {	/* multiple commands with this opcode */
+		r_oip = oip;
+		if (FF_SA & r_oip->flags) {
+			if (F_SA_LOW & oip->flags)
+				sa = 0x1f & cmd[1];
+			else
+				sa = get_unaligned_be16(cmd + 8);
+			for (k = 0; k <= na; oip = r_oip->arrp + k++) {
+				if (opcode == oip->opcode && sa == oip->sa)
+					break;
+			}
+		} else {   /* since no service action only check opcode */
+			for (k = 0; k <= na; oip = r_oip->arrp + k++) {
+				if (opcode == oip->opcode)
+					break;
+			}
+		}
+		if (k > na) {
+			if (F_SA_LOW & r_oip->flags)
+				mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 4);
+			else if (F_SA_HIGH & r_oip->flags)
+				mk_sense_invalid_fld(scp, SDEB_IN_CDB, 8, 7);
+			else
+				mk_sense_invalid_opcode(scp);
+			goto check_cond;
+		}
+	}	/* else (when na==0) we assume the oip is a match */
+	flags = oip->flags;
+	if (F_INV_OP & flags) {
+		mk_sense_invalid_opcode(scp);
+		goto check_cond;
+	}
+	if (has_wlun_rl && !(F_RL_WLUN_OK & flags)) {
+		if (debug)
+			sdev_printk(KERN_INFO, sdp, "scsi_debug: Opcode: "
+				    "0x%x not supported for wlun\n", opcode);
+		mk_sense_invalid_opcode(scp);
+		goto check_cond;
+	}
+	if (scsi_debug_strict) {	/* check cdb against mask */
+		u8 rem;
+		int j;
+
+		for (k = 1; k < oip->len_mask[0] && k < 16; ++k) {
+			rem = ~oip->len_mask[k] & cmd[k];
+			if (rem) {
+				for (j = 7; j >= 0; --j, rem <<= 1) {
+					if (0x80 & rem)
+						break;
+				}
+				mk_sense_invalid_fld(scp, SDEB_IN_CDB, k, j);
+				goto check_cond;
+			}
+		}
+	}
+	if (!(F_SKIP_UA & flags) &&
+	    SDEBUG_NUM_UAS != find_first_bit(devip->uas_bm, SDEBUG_NUM_UAS)) {
+		errsts = check_readiness(scp, UAS_ONLY, devip);
+		if (errsts)
+			goto check_cond;
+	}
+	if ((F_M_ACCESS & flags) && devip->stopped) {
+		mk_sense_buffer(scp, NOT_READY, LOGICAL_UNIT_NOT_READY, 0x2);
+		if (debug)
+			sdev_printk(KERN_INFO, sdp, "%s reports: Not ready: "
+				    "%s\n", my_name, "initializing command "
+				    "required");
+		errsts = check_condition_result;
+		goto fini;
+	}
+	if (scsi_debug_fake_rw && (F_FAKE_RW & flags))
+		goto fini;
+	if (scsi_debug_every_nth) {
+		if (check_inject(scp))
+			return 0;	/* ignore command: make trouble */
+	}
+	if (oip->pfp)	/* if this command has a resp_* function, call it */
+		errsts = oip->pfp(scp, devip);
+	else if (r_pfp)	/* if leaf function ptr NULL, try the root's */
+		errsts = r_pfp(scp, devip);
+
+fini:
+	return schedule_resp(scp, devip, errsts,
+			     ((F_DELAY_OVERR & flags) ? 0 : scsi_debug_delay));
+check_cond:
+	return schedule_resp(scp, devip, check_condition_result, 0);
+}
+
 static struct scsi_host_template sdebug_driver_template = {
 	.show_info =		scsi_debug_show_info,
 	.write_info =		scsi_debug_write_info,