Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 6004 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
new file mode 100644
index 000000000..4d73a7f67
--- /dev/null
+++ b/drivers/scsi/scsi_debug.c
@@ -0,0 +1,6004 @@
+/*
+ * vvvvvvvvvvvvvvvvvvvvvvv Original vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
+ *  Copyright (C) 1992  Eric Youngdale
+ *  Simulate a host adapter with 2 disks attached.  Do a lot of checking
+ *  to make sure that we are not getting blocks mixed up, and PANIC if
+ *  anything out of the ordinary is seen.
+ * ^^^^^^^^^^^^^^^^^^^^^^^ Original ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+ *
+ * Copyright (C) 2001 - 2018 Douglas Gilbert
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ *  For documentation see http://sg.danny.cz/sg/sdebug26.html
+ *
+ */
+
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/jiffies.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/genhd.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/vmalloc.h>
+#include <linux/moduleparam.h>
+#include <linux/scatterlist.h>
+#include <linux/blkdev.h>
+#include <linux/crc-t10dif.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/atomic.h>
+#include <linux/hrtimer.h>
+#include <linux/uuid.h>
+#include <linux/t10-pi.h>
+
+#include <net/checksum.h>
+
+#include <asm/unaligned.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsicam.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_dbg.h>
+
+#include "sd.h"
+#include "scsi_logging.h"
+
+/* make sure inq_product_rev string corresponds to this version */
+#define SDEBUG_VERSION "0188"	/* format to fit INQUIRY revision field */
+static const char *sdebug_version_date = "20190125";
+
+#define MY_NAME "scsi_debug"
+
+/* 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 LBA_OUT_OF_RANGE 0x21
+#define INVALID_FIELD_IN_CDB 0x24
+#define INVALID_FIELD_IN_PARAM_LIST 0x26
+#define UA_RESET_ASC 0x29
+#define UA_CHANGED_ASC 0x2a
+#define TARGET_CHANGED_ASC 0x3f
+#define LUNS_CHANGED_ASCQ 0x0e
+#define INSUFF_RES_ASC 0x55
+#define INSUFF_RES_ASCQ 0x3
+#define POWER_ON_RESET_ASCQ 0x0
+#define BUS_RESET_ASCQ 0x2	/* scsi bus reset occurred */
+#define MODE_CHANGED_ASCQ 0x1	/* mode parameters changed */
+#define CAPACITY_CHANGED_ASCQ 0x9
+#define SAVING_PARAMS_UNSUP 0x39
+#define TRANSPORT_PROBLEM 0x4b
+#define THRESHOLD_EXCEEDED 0x5d
+#define LOW_POWER_COND_ON 0x5e
+#define MISCOMPARE_VERIFY_ASC 0x1d
+#define MICROCODE_CHANGED_ASCQ 0x1	/* with TARGET_CHANGED_ASC */
+#define MICROCODE_CHANGED_WO_RESET_ASCQ 0x16
+#define WRITE_ERROR_ASC 0xc
+
+/* Additional Sense Code Qualifier (ASCQ) */
+#define ACK_NAK_TO 0x3
+
+/* Default values for driver parameters */
+#define DEF_NUM_HOST   1
+#define DEF_NUM_TGTS   1
+#define DEF_MAX_LUNS   1
+/* With these defaults, this driver will make 1 host with 1 target
+ * (id 0) containing 1 logical unit (lun 0). That is 1 device.
+ */
+#define DEF_ATO 1
+#define DEF_CDB_LEN 10
+#define DEF_JDELAY   1		/* if > 0 unit is a jiffy */
+#define DEF_DEV_SIZE_MB   8
+#define DEF_DIF 0
+#define DEF_DIX 0
+#define DEF_D_SENSE   0
+#define DEF_EVERY_NTH   0
+#define DEF_FAKE_RW	0
+#define DEF_GUARD 0
+#define DEF_HOST_LOCK 0
+#define DEF_LBPU 0
+#define DEF_LBPWS 0
+#define DEF_LBPWS10 0
+#define DEF_LBPRZ 1
+#define DEF_LOWEST_ALIGNED 0
+#define DEF_NDELAY   0		/* if > 0 unit is a nanosecond */
+#define DEF_NO_LUN_0   0
+#define DEF_NUM_PARTS   0
+#define DEF_OPTS   0
+#define DEF_OPT_BLKS 1024
+#define DEF_PHYSBLK_EXP 0
+#define DEF_OPT_XFERLEN_EXP 0
+#define DEF_PTYPE   TYPE_DISK
+#define DEF_REMOVABLE false
+#define DEF_SCSI_LEVEL   7    /* INQUIRY, byte2 [6->SPC-4; 7->SPC-5] */
+#define DEF_SECTOR_SIZE 512
+#define DEF_UNMAP_ALIGNMENT 0
+#define DEF_UNMAP_GRANULARITY 1
+#define DEF_UNMAP_MAX_BLOCKS 0xFFFFFFFF
+#define DEF_UNMAP_MAX_DESC 256
+#define DEF_VIRTUAL_GB   0
+#define DEF_VPD_USE_HOSTNO 1
+#define DEF_WRITESAME_LENGTH 0xFFFF
+#define DEF_STRICT 0
+#define DEF_STATISTICS false
+#define DEF_SUBMIT_QUEUES 1
+#define DEF_UUID_CTL 0
+#define JDELAY_OVERRIDDEN -9999
+
+#define SDEBUG_LUN_0_VAL 0
+
+/* bit mask values for sdebug_opts */
+#define SDEBUG_OPT_NOISE		1
+#define SDEBUG_OPT_MEDIUM_ERR		2
+#define SDEBUG_OPT_TIMEOUT		4
+#define SDEBUG_OPT_RECOVERED_ERR	8
+#define SDEBUG_OPT_TRANSPORT_ERR	16
+#define SDEBUG_OPT_DIF_ERR		32
+#define SDEBUG_OPT_DIX_ERR		64
+#define SDEBUG_OPT_MAC_TIMEOUT		128
+#define SDEBUG_OPT_SHORT_TRANSFER	0x100
+#define SDEBUG_OPT_Q_NOISE		0x200
+#define SDEBUG_OPT_ALL_TSF		0x400
+#define SDEBUG_OPT_RARE_TSF		0x800
+#define SDEBUG_OPT_N_WCE		0x1000
+#define SDEBUG_OPT_RESET_NOISE		0x2000
+#define SDEBUG_OPT_NO_CDB_NOISE		0x4000
+#define SDEBUG_OPT_HOST_BUSY		0x8000
+#define SDEBUG_OPT_CMD_ABORT		0x10000
+#define SDEBUG_OPT_ALL_NOISE (SDEBUG_OPT_NOISE | SDEBUG_OPT_Q_NOISE | \
+			      SDEBUG_OPT_RESET_NOISE)
+#define SDEBUG_OPT_ALL_INJECTING (SDEBUG_OPT_RECOVERED_ERR | \
+				  SDEBUG_OPT_TRANSPORT_ERR | \
+				  SDEBUG_OPT_DIF_ERR | SDEBUG_OPT_DIX_ERR | \
+				  SDEBUG_OPT_SHORT_TRANSFER | \
+				  SDEBUG_OPT_HOST_BUSY | \
+				  SDEBUG_OPT_CMD_ABORT)
+/* When "every_nth" > 0 then modulo "every_nth" commands:
+ *   - a missing response is simulated if SDEBUG_OPT_TIMEOUT is set
+ *   - a RECOVERED_ERROR is simulated on successful read and write
+ *     commands if SDEBUG_OPT_RECOVERED_ERR is set.
+ *   - a TRANSPORT_ERROR is simulated on successful read and write
+ *     commands if SDEBUG_OPT_TRANSPORT_ERR is set.
+ *   - similarly for DIF_ERR, DIX_ERR, SHORT_TRANSFER, HOST_BUSY and
+ *     CMD_ABORT
+ *
+ * When "every_nth" < 0 then after "- every_nth" commands the selected
+ * error will be injected. The error will be injected on every subsequent
+ * command until some other action occurs; for example, the user writing
+ * a new value (other than -1 or 1) to every_nth:
+ *      echo 0 > /sys/bus/pseudo/drivers/scsi_debug/every_nth
+ */
+
+/* As indicated in SAM-5 and SPC-4 Unit Attentions (UAs) are returned in
+ * priority order. In the subset implemented here lower numbers have higher
+ * priority. The UA numbers should be a sequence starting from 0 with
+ * SDEBUG_NUM_UAS being 1 higher than the highest numbered UA. */
+#define SDEBUG_UA_POR 0		/* Power on, reset, or bus device reset */
+#define SDEBUG_UA_BUS_RESET 1
+#define SDEBUG_UA_MODE_CHANGED 2
+#define SDEBUG_UA_CAPACITY_CHANGED 3
+#define SDEBUG_UA_LUNS_CHANGED 4
+#define SDEBUG_UA_MICROCODE_CHANGED 5	/* simulate firmware change */
+#define SDEBUG_UA_MICROCODE_CHANGED_WO_RESET 6
+#define SDEBUG_NUM_UAS 7
+
+/* when 1==SDEBUG_OPT_MEDIUM_ERR, a medium error is simulated at this
+ * sector on read commands: */
+#define OPT_MEDIUM_ERR_ADDR   0x1234 /* that's sector 4660 in decimal */
+#define OPT_MEDIUM_ERR_NUM    10     /* number of consecutive medium errs */
+
+/* If REPORT LUNS has luns >= 256 it can choose "flat space" (value 1)
+ * or "peripheral device" addressing (value 0) */
+#define SAM2_LUN_ADDRESS_METHOD 0
+
+/* SDEBUG_CANQUEUE is the maximum number of commands that can be queued
+ * (for response) per submit queue at one time. Can be reduced by max_queue
+ * option. Command responses are not queued when jdelay=0 and ndelay=0. The
+ * per-device DEF_CMD_PER_LUN can be changed via sysfs:
+ * /sys/class/scsi_device/<h:c:t:l>/device/queue_depth
+ * but cannot exceed SDEBUG_CANQUEUE .
+ */
+#define SDEBUG_CANQUEUE_WORDS  3	/* a WORD is bits in a long */
+#define SDEBUG_CANQUEUE  (SDEBUG_CANQUEUE_WORDS * BITS_PER_LONG)
+#define DEF_CMD_PER_LUN  255
+
+#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 F_SSU_DELAY		0x1000
+#define F_SYNC_DELAY		0x2000
+
+#define FF_RESPOND (F_RL_WLUN_OK | F_SKIP_UA | F_DELAY_OVERR)
+#define FF_MEDIA_IO (F_M_ACCESS | F_FAKE_RW)
+#define FF_SA (F_SA_HIGH | F_SA_LOW)
+#define F_LONG_DELAY		(F_SSU_DELAY | F_SYNC_DELAY)
+
+#define SDEBUG_MAX_PARTS 4
+
+#define SDEBUG_MAX_CMD_LEN 32
+
+
+struct sdebug_dev_info {
+	struct list_head dev_list;
+	unsigned int channel;
+	unsigned int target;
+	u64 lun;
+	uuid_t lu_name;
+	struct sdebug_host_info *sdbg_host;
+	unsigned long uas_bm[1];
+	atomic_t num_in_q;
+	atomic_t stopped;
+	bool used;
+};
+
+struct sdebug_host_info {
+	struct list_head host_list;
+	struct Scsi_Host *shost;
+	struct device dev;
+	struct list_head dev_info_list;
+};
+
+#define to_sdebug_host(d)	\
+	container_of(d, struct sdebug_host_info, dev)
+
+enum sdeb_defer_type {SDEB_DEFER_NONE = 0, SDEB_DEFER_HRT = 1,
+		      SDEB_DEFER_WQ = 2};
+
+struct sdebug_defer {
+	struct hrtimer hrt;
+	struct execute_work ew;
+	int sqa_idx;	/* index of sdebug_queue array */
+	int qc_idx;	/* index of sdebug_queued_cmd array within sqa_idx */
+	int issuing_cpu;
+	bool init_hrt;
+	bool init_wq;
+	bool aborted;	/* true when blk_abort_request() already called */
+	enum sdeb_defer_type defer_t;
+};
+
+struct sdebug_queued_cmd {
+	/* corresponding bit set in in_use_bm[] in owning struct sdebug_queue
+	 * instance indicates this slot is in use.
+	 */
+	struct sdebug_defer *sd_dp;
+	struct scsi_cmnd *a_cmnd;
+	unsigned int inj_recovered:1;
+	unsigned int inj_transport:1;
+	unsigned int inj_dif:1;
+	unsigned int inj_dix:1;
+	unsigned int inj_short:1;
+	unsigned int inj_host_busy:1;
+	unsigned int inj_cmd_abort:1;
+};
+
+struct sdebug_queue {
+	struct sdebug_queued_cmd qc_arr[SDEBUG_CANQUEUE];
+	unsigned long in_use_bm[SDEBUG_CANQUEUE_WORDS];
+	spinlock_t qc_lock;
+	atomic_t blocked;	/* to temporarily stop more being queued */
+};
+
+static atomic_t sdebug_cmnd_count;   /* number of incoming commands */
+static atomic_t sdebug_completions;  /* count of deferred completions */
+static atomic_t sdebug_miss_cpus;    /* submission + completion cpus differ */
+static atomic_t sdebug_a_tsf;	     /* 'almost task set full' counter */
+
+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_mask[0]-->cdb_len, then mask for cdb */
+				/* 1 to min(cdb_len, 15); ignore cdb[15...] */
+};
+
+/* SCSI opcodes (first byte of cdb) of interest 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_16 = 12,	/* add ...SERV_ACT_IN_12 if needed */
+	SDEB_I_SERV_ACT_OUT_16 = 13,	/* add ...SERV_ACT_OUT_12 if needed */
+	SDEB_I_MAINT_IN = 14,
+	SDEB_I_MAINT_OUT = 15,
+	SDEB_I_VERIFY = 16,		/* 10 only */
+	SDEB_I_VARIABLE_LEN = 17,	/* READ(32), WRITE(32), WR_SCAT(32) */
+	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, 16 */
+	SDEB_I_COMP_WRITE = 29,
+	SDEB_I_LAST_ELEMENT = 30,	/* keep this last (previous + 1) */
+};
+
+
+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, 0x7e is "extended cdb" */
+	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, SDEB_I_SYNC_CACHE, 0, SDEB_I_WRITE_SAME, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, SDEB_I_SERV_ACT_IN_16, SDEB_I_SERV_ACT_OUT_16,
+/* 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, 0 /* SDEB_I_SERV_ACT_OUT_12 */, SDEB_I_WRITE,
+	     0 /* SDEB_I_SERV_ACT_IN_12 */, 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,
+};
+
+/*
+ * The following "response" functions return the SCSI mid-level's 4 byte
+ * tuple-in-an-int. To handle commands with an IMMED bit, for a faster
+ * command completion, they can mask their return value with
+ * SDEG_RES_IMMED_MASK .
+ */
+#define SDEG_RES_IMMED_MASK 0x40000000
+
+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_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_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 *);
+static int resp_rsup_tmfs(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 *);
+static int resp_comp_write(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_write_buffer(struct scsi_cmnd *, struct sdebug_dev_info *);
+static int resp_sync_cache(struct scsi_cmnd *, struct sdebug_dev_info *);
+
+/*
+ * The following are overflow arrays for cdbs that "hit" the same index in
+ * the opcode_info_arr array. The most time sensitive (or commonly used) cdb
+ * should be placed in opcode_info_arr[], the others should be placed here.
+ */
+static const struct opcode_info_t msense_iarr[] = {
+	{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[] = {
+	{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[] = {
+	{0, 0x28, 0, F_D_IN | FF_MEDIA_IO, resp_read_dt0, NULL,/* READ(10) */
+	    {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
+	     0, 0, 0, 0} },
+	{0, 0x8, 0, F_D_IN | FF_MEDIA_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_MEDIA_IO, resp_read_dt0, NULL,/* READ(12) */
+	    {12,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xbf,
+	     0xc7, 0, 0, 0, 0} },
+};
+
+static const struct opcode_info_t write_iarr[] = {
+	{0, 0x2a, 0, F_D_OUT | FF_MEDIA_IO, resp_write_dt0,  /* WRITE(10) */
+	    NULL, {10,  0xfb, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7,
+		   0, 0, 0, 0, 0, 0} },
+	{0, 0xa, 0, F_D_OUT | FF_MEDIA_IO, resp_write_dt0,   /* WRITE(6) */
+	    NULL, {6,  0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0, 0,
+		   0, 0, 0} },
+	{0, 0xaa, 0, F_D_OUT | FF_MEDIA_IO, resp_write_dt0,  /* WRITE(12) */
+	    NULL, {12,  0xfb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+		   0xbf, 0xc7, 0, 0, 0, 0} },
+};
+
+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) */
+};
+
+static const struct opcode_info_t vl_iarr[] = {	/* VARIABLE LENGTH */
+	{0, 0x7f, 0xb, F_SA_HIGH | F_D_OUT | FF_MEDIA_IO, resp_write_dt0,
+	    NULL, {32,  0xc7, 0, 0, 0, 0, 0x3f, 0x18, 0x0, 0xb, 0xfa,
+		   0, 0xff, 0xff, 0xff, 0xff} },	/* WRITE(32) */
+	{0, 0x7f, 0x11, F_SA_HIGH | F_D_OUT | FF_MEDIA_IO, resp_write_scat,
+	    NULL, {32,  0xc7, 0, 0, 0, 0, 0x3f, 0x18, 0x0, 0x11, 0xf8,
+		   0, 0xff, 0xff, 0x0, 0x0} },	/* WRITE SCATTERED(32) */
+};
+
+static const struct opcode_info_t maint_in_iarr[] = {	/* MAINT IN */
+	{0, 0xa3, 0xc, F_SA_LOW | F_D_IN, resp_rsup_opcodes, NULL,
+	    {12,  0xc, 0x87, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0,
+	     0xc7, 0, 0, 0, 0} }, /* REPORT SUPPORTED OPERATION CODES */
+	{0, 0xa3, 0xd, F_SA_LOW | F_D_IN, resp_rsup_tmfs, NULL,
+	    {12,  0xd, 0x80, 0, 0, 0, 0xff, 0xff, 0xff, 0xff, 0, 0xc7, 0, 0,
+	     0, 0} },	/* REPORTED SUPPORTED TASK MANAGEMENT FUNCTIONS */
+};
+
+static const struct opcode_info_t write_same_iarr[] = {
+	{0, 0x93, 0, F_D_OUT_MAYBE | FF_MEDIA_IO, resp_write_same_16, NULL,
+	    {16,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	     0xff, 0xff, 0xff, 0x3f, 0xc7} },		/* WRITE SAME(16) */
+};
+
+static const struct opcode_info_t reserve_iarr[] = {
+	{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[] = {
+	{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} },
+};
+
+static const struct opcode_info_t sync_cache_iarr[] = {
+	{0, 0x91, 0, F_SYNC_DELAY | F_M_ACCESS, resp_sync_cache, NULL,
+	    {16,  0x6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	     0xff, 0xff, 0xff, 0xff, 0x3f, 0xc7} },	/* SYNC_CACHE (16) */
+};
+
+
+/* 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,	/* unknown opcodes */
+	    {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, /* INQUIRY */
+	    {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} },					/* REPORT LUNS */
+	{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} },
+/* 5 */
+	{ARRAY_SIZE(msense_iarr), 0x5a, 0, F_D_IN,	/* MODE SENSE(10) */
+	    resp_mode_sense, msense_iarr, {10,  0xf8, 0xff, 0xff, 0, 0, 0,
+		0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
+	{ARRAY_SIZE(mselect_iarr), 0x55, 0, F_D_OUT,	/* MODE SELECT(10) */
+	    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,	/* LOG SENSE */
+	    {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,    /* READ CAPACITY(10) */
+	    {10,  0xe1, 0xff, 0xff, 0xff, 0xff, 0, 0, 0x1, 0xc7, 0, 0, 0, 0,
+	     0, 0} },
+	{ARRAY_SIZE(read_iarr), 0x88, 0, F_D_IN | FF_MEDIA_IO, /* READ(16) */
+	    resp_read_dt0, read_iarr, {16,  0xfe, 0xff, 0xff, 0xff, 0xff,
+	    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7} },
+/* 10 */
+	{ARRAY_SIZE(write_iarr), 0x8a, 0, F_D_OUT | FF_MEDIA_IO,
+	    resp_write_dt0, write_iarr,			/* WRITE(16) */
+		{16,  0xfa, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+		 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7} },
+	{0, 0x1b, 0, F_SSU_DELAY, resp_start_stop, NULL,/* START STOP UNIT */
+	    {6,  0x1, 0, 0xf, 0xf7, 0xc7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} },
+	{ARRAY_SIZE(sa_in_16_iarr), 0x9e, 0x10, F_SA_LOW | F_D_IN,
+	    resp_readcap16, sa_in_16_iarr, /* SA_IN(16), READ CAPACITY(16) */
+		{16,  0x10, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+		 0xff, 0xff, 0xff, 0xff, 0x1, 0xc7} },
+	{0, 0x9f, 0x12, F_SA_LOW | F_D_OUT | FF_MEDIA_IO, resp_write_scat,
+	    NULL, {16,  0x12, 0xf9, 0x0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0xff,
+	    0xff, 0xff, 0xff, 0xff, 0xc7} },  /* SA_OUT(16), WRITE SCAT(16) */
+	{ARRAY_SIZE(maint_in_iarr), 0xa3, 0xa, F_SA_LOW | F_D_IN,
+	    resp_report_tgtpgs,	/* MAINT IN, REPORT TARGET PORT GROUPS */
+		maint_in_iarr, {12,  0xea, 0, 0, 0, 0, 0xff, 0xff, 0xff,
+				0xff, 0, 0xc7, 0, 0, 0, 0} },
+/* 15 */
+	{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, 0x2f, 0, F_D_OUT_MAYBE | FF_MEDIA_IO, NULL, NULL, /* VERIFY(10) */
+	    {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7,
+	     0, 0, 0, 0, 0, 0} },
+	{ARRAY_SIZE(vl_iarr), 0x7f, 0x9, F_SA_HIGH | F_D_IN | FF_MEDIA_IO,
+	    resp_read_dt0, vl_iarr,	/* VARIABLE LENGTH, READ(32) */
+	    {32,  0xc7, 0, 0, 0, 0, 0x3f, 0x18, 0x0, 0x9, 0xfe, 0, 0xff, 0xff,
+	     0xff, 0xff} },
+	{ARRAY_SIZE(reserve_iarr), 0x56, 0, F_D_OUT,
+	    NULL, reserve_iarr,	/* RESERVE(10) <no response function> */
+	    {10,  0xff, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
+	     0} },
+	{ARRAY_SIZE(release_iarr), 0x57, 0, F_D_OUT,
+	    NULL, release_iarr, /* RELEASE(10) <no response function> */
+	    {10,  0x13, 0xff, 0xff, 0, 0, 0, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0,
+	     0} },
+/* 20 */
+	{0, 0x1e, 0, 0, NULL, NULL, /* ALLOW REMOVAL */
+	    {6,  0, 0, 0, 0x3, 0xc7, 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_MEDIA_IO, resp_unmap, NULL, /* UNMAP */
+	    {10,  0x1, 0, 0, 0, 0, 0x3f, 0xff, 0xff, 0xc7, 0, 0, 0, 0, 0, 0} },
+/* 25 */
+	{0, 0x53, 0, F_D_IN | F_D_OUT | FF_MEDIA_IO, resp_xdwriteread_10,
+	    NULL, {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7,
+		   0, 0, 0, 0, 0, 0} },		/* XDWRITEREAD(10) */
+	{0, 0x3b, 0, F_D_OUT_MAYBE, resp_write_buffer, NULL,
+	    {10,  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7, 0, 0,
+	     0, 0, 0, 0} },			/* WRITE_BUFFER */
+	{ARRAY_SIZE(write_same_iarr), 0x41, 0, F_D_OUT_MAYBE | FF_MEDIA_IO,
+	    resp_write_same_10, write_same_iarr,	/* WRITE SAME(10) */
+		{10,  0xff, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0,
+		 0, 0, 0, 0, 0} },
+	{ARRAY_SIZE(sync_cache_iarr), 0x35, 0, F_SYNC_DELAY | F_M_ACCESS,
+	    resp_sync_cache, sync_cache_iarr,
+	    {10,  0x7, 0xff, 0xff, 0xff, 0xff, 0x3f, 0xff, 0xff, 0xc7, 0, 0,
+	     0, 0, 0, 0} },			/* SYNC_CACHE (10) */
+	{0, 0x89, 0, F_D_OUT | FF_MEDIA_IO, resp_comp_write, NULL,
+	    {16,  0xf8, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0,
+	     0, 0xff, 0x3f, 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} },
+};
+
+static int sdebug_add_host = DEF_NUM_HOST;
+static int sdebug_ato = DEF_ATO;
+static int sdebug_cdb_len = DEF_CDB_LEN;
+static int sdebug_jdelay = DEF_JDELAY;	/* if > 0 then unit is jiffies */
+static int sdebug_dev_size_mb = DEF_DEV_SIZE_MB;
+static int sdebug_dif = DEF_DIF;
+static int sdebug_dix = DEF_DIX;
+static int sdebug_dsense = DEF_D_SENSE;
+static int sdebug_every_nth = DEF_EVERY_NTH;
+static int sdebug_fake_rw = DEF_FAKE_RW;
+static unsigned int sdebug_guard = DEF_GUARD;
+static int sdebug_lowest_aligned = DEF_LOWEST_ALIGNED;
+static int sdebug_max_luns = DEF_MAX_LUNS;
+static int sdebug_max_queue = SDEBUG_CANQUEUE;	/* per submit queue */
+static unsigned int sdebug_medium_error_start = OPT_MEDIUM_ERR_ADDR;
+static int sdebug_medium_error_count = OPT_MEDIUM_ERR_NUM;
+static atomic_t retired_max_queue;	/* if > 0 then was prior max_queue */
+static int sdebug_ndelay = DEF_NDELAY;	/* if > 0 then unit is nanoseconds */
+static int sdebug_no_lun_0 = DEF_NO_LUN_0;
+static int sdebug_no_uld;
+static int sdebug_num_parts = DEF_NUM_PARTS;
+static int sdebug_num_tgts = DEF_NUM_TGTS; /* targets per host */
+static int sdebug_opt_blks = DEF_OPT_BLKS;
+static int sdebug_opts = DEF_OPTS;
+static int sdebug_physblk_exp = DEF_PHYSBLK_EXP;
+static int sdebug_opt_xferlen_exp = DEF_OPT_XFERLEN_EXP;
+static int sdebug_ptype = DEF_PTYPE; /* SCSI peripheral device type */
+static int sdebug_scsi_level = DEF_SCSI_LEVEL;
+static int sdebug_sector_size = DEF_SECTOR_SIZE;
+static int sdebug_virtual_gb = DEF_VIRTUAL_GB;
+static int sdebug_vpd_use_hostno = DEF_VPD_USE_HOSTNO;
+static unsigned int sdebug_lbpu = DEF_LBPU;
+static unsigned int sdebug_lbpws = DEF_LBPWS;
+static unsigned int sdebug_lbpws10 = DEF_LBPWS10;
+static unsigned int sdebug_lbprz = DEF_LBPRZ;
+static unsigned int sdebug_unmap_alignment = DEF_UNMAP_ALIGNMENT;
+static unsigned int sdebug_unmap_granularity = DEF_UNMAP_GRANULARITY;
+static unsigned int sdebug_unmap_max_blocks = DEF_UNMAP_MAX_BLOCKS;
+static unsigned int sdebug_unmap_max_desc = DEF_UNMAP_MAX_DESC;
+static unsigned int sdebug_write_same_length = DEF_WRITESAME_LENGTH;
+static int sdebug_uuid_ctl = DEF_UUID_CTL;
+static bool sdebug_removable = DEF_REMOVABLE;
+static bool sdebug_clustering;
+static bool sdebug_host_lock = DEF_HOST_LOCK;
+static bool sdebug_strict = DEF_STRICT;
+static bool sdebug_any_injecting_opt;
+static bool sdebug_verbose;
+static bool have_dif_prot;
+static bool write_since_sync;
+static bool sdebug_statistics = DEF_STATISTICS;
+
+static unsigned int sdebug_store_sectors;
+static sector_t sdebug_capacity;	/* in sectors */
+
+/* old BIOS stuff, kernel may get rid of them but some mode sense pages
+   may still need them */
+static int sdebug_heads;		/* heads per disk */
+static int sdebug_cylinders_per;	/* cylinders per surface */
+static int sdebug_sectors_per;		/* sectors per cylinder */
+
+static LIST_HEAD(sdebug_host_list);
+static DEFINE_SPINLOCK(sdebug_host_list_lock);
+
+static unsigned char *fake_storep;	/* ramdisk storage */
+static struct t10_pi_tuple *dif_storep;	/* protection info */
+static void *map_storep;		/* provisioning map */
+
+static unsigned long map_size;
+static int num_aborts;
+static int num_dev_resets;
+static int num_target_resets;
+static int num_bus_resets;
+static int num_host_resets;
+static int dix_writes;
+static int dix_reads;
+static int dif_errors;
+
+static int submit_queues = DEF_SUBMIT_QUEUES;  /* > 1 for multi-queue (mq) */
+static struct sdebug_queue *sdebug_q_arr;  /* ptr to array of submit queues */
+
+static DEFINE_RWLOCK(atomic_rw);
+
+static char sdebug_proc_name[] = MY_NAME;
+static const char *my_name = MY_NAME;
+
+static struct bus_type pseudo_lld_bus;
+
+static struct device_driver sdebug_driverfs_driver = {
+	.name 		= sdebug_proc_name,
+	.bus		= &pseudo_lld_bus,
+};
+
+static const int check_condition_result =
+		(DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
+
+static const int illegal_condition_result =
+	(DRIVER_SENSE << 24) | (DID_ABORT << 16) | SAM_STAT_CHECK_CONDITION;
+
+static const int device_qfull_result =
+	(DID_OK << 16) | (COMMAND_COMPLETE << 8) | SAM_STAT_TASK_SET_FULL;
+
+
+/* Only do the extra work involved in logical block provisioning if one or
+ * more of the lbpu, lbpws or lbpws10 parameters are given and we are doing
+ * real reads and writes (i.e. not skipping them for speed).
+ */
+static inline bool scsi_debug_lbp(void)
+{
+	return 0 == sdebug_fake_rw &&
+		(sdebug_lbpu || sdebug_lbpws || sdebug_lbpws10);
+}
+
+static void *lba2fake_store(unsigned long long lba)
+{
+	lba = do_div(lba, sdebug_store_sectors);
+
+	return fake_storep + lba * sdebug_sector_size;
+}
+
+static struct t10_pi_tuple *dif_store(sector_t sector)
+{
+	sector = sector_div(sector, sdebug_store_sectors);
+
+	return dif_storep + sector;
+}
+
+static void sdebug_max_tgts_luns(void)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct Scsi_Host *hpnt;
+
+	spin_lock(&sdebug_host_list_lock);
+	list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
+		hpnt = sdbg_host->shost;
+		if ((hpnt->this_id >= 0) &&
+		    (sdebug_num_tgts > hpnt->this_id))
+			hpnt->max_id = sdebug_num_tgts + 1;
+		else
+			hpnt->max_id = sdebug_num_tgts;
+		/* sdebug_max_luns; */
+		hpnt->max_lun = SCSI_W_LUN_REPORT_LUNS + 1;
+	}
+	spin_unlock(&sdebug_host_list_lock);
+}
+
+enum sdeb_cmd_data {SDEB_IN_DATA = 0, SDEB_IN_CDB = 1};
+
+/* Set in_bit to -1 to indicate no bit position of invalid field */
+static void mk_sense_invalid_fld(struct scsi_cmnd *scp,
+				 enum sdeb_cmd_data c_d,
+				 int in_byte, int in_bit)
+{
+	unsigned char *sbuff;
+	u8 sks[4];
+	int sl, asc;
+
+	sbuff = scp->sense_buffer;
+	if (!sbuff) {
+		sdev_printk(KERN_ERR, scp->device,
+			    "%s: sense_buffer is NULL\n", __func__);
+		return;
+	}
+	asc = c_d ? INVALID_FIELD_IN_CDB : INVALID_FIELD_IN_PARAM_LIST;
+	memset(sbuff, 0, SCSI_SENSE_BUFFERSIZE);
+	scsi_build_sense_buffer(sdebug_dsense, sbuff, ILLEGAL_REQUEST, asc, 0);
+	memset(sks, 0, sizeof(sks));
+	sks[0] = 0x80;
+	if (c_d)
+		sks[0] |= 0x40;
+	if (in_bit >= 0) {
+		sks[0] |= 0x8;
+		sks[0] |= 0x7 & in_bit;
+	}
+	put_unaligned_be16(in_byte, sks + 1);
+	if (sdebug_dsense) {
+		sl = sbuff[7] + 8;
+		sbuff[7] = sl;
+		sbuff[sl] = 0x2;
+		sbuff[sl + 1] = 0x6;
+		memcpy(sbuff + sl + 4, sks, 3);
+	} else
+		memcpy(sbuff + 15, sks, 3);
+	if (sdebug_verbose)
+		sdev_printk(KERN_INFO, scp->device, "%s:  [sense_key,asc,ascq"
+			    "]: [0x5,0x%x,0x0] %c byte=%d, bit=%d\n",
+			    my_name, asc, c_d ? 'C' : 'D', in_byte, in_bit);
+}
+
+static void mk_sense_buffer(struct scsi_cmnd *scp, int key, int asc, int asq)
+{
+	unsigned char *sbuff;
+
+	sbuff = scp->sense_buffer;
+	if (!sbuff) {
+		sdev_printk(KERN_ERR, scp->device,
+			    "%s: sense_buffer is NULL\n", __func__);
+		return;
+	}
+	memset(sbuff, 0, SCSI_SENSE_BUFFERSIZE);
+
+	scsi_build_sense_buffer(sdebug_dsense, sbuff, key, asc, asq);
+
+	if (sdebug_verbose)
+		sdev_printk(KERN_INFO, scp->device,
+			    "%s:  [sense_key,asc,ascq]: [0x%x,0x%x,0x%x]\n",
+			    my_name, key, asc, asq);
+}
+
+static void mk_sense_invalid_opcode(struct scsi_cmnd *scp)
+{
+	mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_OPCODE, 0);
+}
+
+static int scsi_debug_ioctl(struct scsi_device *dev, int cmd, void __user *arg)
+{
+	if (sdebug_verbose) {
+		if (0x1261 == cmd)
+			sdev_printk(KERN_INFO, dev,
+				    "%s: BLKFLSBUF [0x1261]\n", __func__);
+		else if (0x5331 == cmd)
+			sdev_printk(KERN_INFO, dev,
+				    "%s: CDROM_GET_CAPABILITY [0x5331]\n",
+				    __func__);
+		else
+			sdev_printk(KERN_INFO, dev, "%s: cmd=0x%x\n",
+				    __func__, cmd);
+	}
+	return -EINVAL;
+	/* return -ENOTTY; // correct return but upsets fdisk */
+}
+
+static void config_cdb_len(struct scsi_device *sdev)
+{
+	switch (sdebug_cdb_len) {
+	case 6:	/* suggest 6 byte READ, WRITE and MODE SENSE/SELECT */
+		sdev->use_10_for_rw = false;
+		sdev->use_16_for_rw = false;
+		sdev->use_10_for_ms = false;
+		break;
+	case 10: /* suggest 10 byte RWs and 6 byte MODE SENSE/SELECT */
+		sdev->use_10_for_rw = true;
+		sdev->use_16_for_rw = false;
+		sdev->use_10_for_ms = false;
+		break;
+	case 12: /* suggest 10 byte RWs and 10 byte MODE SENSE/SELECT */
+		sdev->use_10_for_rw = true;
+		sdev->use_16_for_rw = false;
+		sdev->use_10_for_ms = true;
+		break;
+	case 16:
+		sdev->use_10_for_rw = false;
+		sdev->use_16_for_rw = true;
+		sdev->use_10_for_ms = true;
+		break;
+	case 32: /* No knobs to suggest this so same as 16 for now */
+		sdev->use_10_for_rw = false;
+		sdev->use_16_for_rw = true;
+		sdev->use_10_for_ms = true;
+		break;
+	default:
+		pr_warn("unexpected cdb_len=%d, force to 10\n",
+			sdebug_cdb_len);
+		sdev->use_10_for_rw = true;
+		sdev->use_16_for_rw = false;
+		sdev->use_10_for_ms = false;
+		sdebug_cdb_len = 10;
+		break;
+	}
+}
+
+static void all_config_cdb_len(void)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct Scsi_Host *shost;
+	struct scsi_device *sdev;
+
+	spin_lock(&sdebug_host_list_lock);
+	list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
+		shost = sdbg_host->shost;
+		shost_for_each_device(sdev, shost) {
+			config_cdb_len(sdev);
+		}
+	}
+	spin_unlock(&sdebug_host_list_lock);
+}
+
+static void clear_luns_changed_on_target(struct sdebug_dev_info *devip)
+{
+	struct sdebug_host_info *sdhp;
+	struct sdebug_dev_info *dp;
+
+	spin_lock(&sdebug_host_list_lock);
+	list_for_each_entry(sdhp, &sdebug_host_list, host_list) {
+		list_for_each_entry(dp, &sdhp->dev_info_list, dev_list) {
+			if ((devip->sdbg_host == dp->sdbg_host) &&
+			    (devip->target == dp->target))
+				clear_bit(SDEBUG_UA_LUNS_CHANGED, dp->uas_bm);
+		}
+	}
+	spin_unlock(&sdebug_host_list_lock);
+}
+
+static int make_ua(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
+{
+	int k;
+
+	k = find_first_bit(devip->uas_bm, SDEBUG_NUM_UAS);
+	if (k != SDEBUG_NUM_UAS) {
+		const char *cp = NULL;
+
+		switch (k) {
+		case SDEBUG_UA_POR:
+			mk_sense_buffer(scp, UNIT_ATTENTION, UA_RESET_ASC,
+					POWER_ON_RESET_ASCQ);
+			if (sdebug_verbose)
+				cp = "power on reset";
+			break;
+		case SDEBUG_UA_BUS_RESET:
+			mk_sense_buffer(scp, UNIT_ATTENTION, UA_RESET_ASC,
+					BUS_RESET_ASCQ);
+			if (sdebug_verbose)
+				cp = "bus reset";
+			break;
+		case SDEBUG_UA_MODE_CHANGED:
+			mk_sense_buffer(scp, UNIT_ATTENTION, UA_CHANGED_ASC,
+					MODE_CHANGED_ASCQ);
+			if (sdebug_verbose)
+				cp = "mode parameters changed";
+			break;
+		case SDEBUG_UA_CAPACITY_CHANGED:
+			mk_sense_buffer(scp, UNIT_ATTENTION, UA_CHANGED_ASC,
+					CAPACITY_CHANGED_ASCQ);
+			if (sdebug_verbose)
+				cp = "capacity data changed";
+			break;
+		case SDEBUG_UA_MICROCODE_CHANGED:
+			mk_sense_buffer(scp, UNIT_ATTENTION,
+					TARGET_CHANGED_ASC,
+					MICROCODE_CHANGED_ASCQ);
+			if (sdebug_verbose)
+				cp = "microcode has been changed";
+			break;
+		case SDEBUG_UA_MICROCODE_CHANGED_WO_RESET:
+			mk_sense_buffer(scp, UNIT_ATTENTION,
+					TARGET_CHANGED_ASC,
+					MICROCODE_CHANGED_WO_RESET_ASCQ);
+			if (sdebug_verbose)
+				cp = "microcode has been changed without reset";
+			break;
+		case SDEBUG_UA_LUNS_CHANGED:
+			/*
+			 * SPC-3 behavior is to report a UNIT ATTENTION with
+			 * ASC/ASCQ REPORTED LUNS DATA HAS CHANGED on every LUN
+			 * on the target, until a REPORT LUNS command is
+			 * received.  SPC-4 behavior is to report it only once.
+			 * NOTE:  sdebug_scsi_level does not use the same
+			 * values as struct scsi_device->scsi_level.
+			 */
+			if (sdebug_scsi_level >= 6)	/* SPC-4 and above */
+				clear_luns_changed_on_target(devip);
+			mk_sense_buffer(scp, UNIT_ATTENTION,
+					TARGET_CHANGED_ASC,
+					LUNS_CHANGED_ASCQ);
+			if (sdebug_verbose)
+				cp = "reported luns data has changed";
+			break;
+		default:
+			pr_warn("unexpected unit attention code=%d\n", k);
+			if (sdebug_verbose)
+				cp = "unknown";
+			break;
+		}
+		clear_bit(k, devip->uas_bm);
+		if (sdebug_verbose)
+			sdev_printk(KERN_INFO, scp->device,
+				   "%s reports: Unit attention: %s\n",
+				   my_name, cp);
+		return check_condition_result;
+	}
+	return 0;
+}
+
+/* Build SCSI "data-in" buffer. Returns 0 if ok else (DID_ERROR << 16). */
+static int fill_from_dev_buffer(struct scsi_cmnd *scp, unsigned char *arr,
+				int arr_len)
+{
+	int act_len;
+	struct scsi_data_buffer *sdb = scsi_in(scp);
+
+	if (!sdb->length)
+		return 0;
+	if (!(scsi_bidi_cmnd(scp) || scp->sc_data_direction == DMA_FROM_DEVICE))
+		return DID_ERROR << 16;
+
+	act_len = sg_copy_from_buffer(sdb->table.sgl, sdb->table.nents,
+				      arr, arr_len);
+	sdb->resid = scsi_bufflen(scp) - act_len;
+
+	return 0;
+}
+
+/* Partial build of SCSI "data-in" buffer. Returns 0 if ok else
+ * (DID_ERROR << 16). Can write to offset in data-in buffer. If multiple
+ * calls, not required to write in ascending offset order. Assumes resid
+ * set to scsi_bufflen() prior to any calls.
+ */
+static int p_fill_from_dev_buffer(struct scsi_cmnd *scp, const void *arr,
+				  int arr_len, unsigned int off_dst)
+{
+	int act_len, n;
+	struct scsi_data_buffer *sdb = scsi_in(scp);
+	off_t skip = off_dst;
+
+	if (sdb->length <= off_dst)
+		return 0;
+	if (!(scsi_bidi_cmnd(scp) || scp->sc_data_direction == DMA_FROM_DEVICE))
+		return DID_ERROR << 16;
+
+	act_len = sg_pcopy_from_buffer(sdb->table.sgl, sdb->table.nents,
+				       arr, arr_len, skip);
+	pr_debug("%s: off_dst=%u, scsi_bufflen=%u, act_len=%u, resid=%d\n",
+		 __func__, off_dst, scsi_bufflen(scp), act_len, sdb->resid);
+	n = (int)scsi_bufflen(scp) - ((int)off_dst + act_len);
+	sdb->resid = min(sdb->resid, n);
+	return 0;
+}
+
+/* Fetches from SCSI "data-out" buffer. Returns number of bytes fetched into
+ * 'arr' or -1 if error.
+ */
+static int fetch_to_dev_buffer(struct scsi_cmnd *scp, unsigned char *arr,
+			       int arr_len)
+{
+	if (!scsi_bufflen(scp))
+		return 0;
+	if (!(scsi_bidi_cmnd(scp) || scp->sc_data_direction == DMA_TO_DEVICE))
+		return -1;
+
+	return scsi_sg_copy_to_buffer(scp, arr, arr_len);
+}
+
+
+static char sdebug_inq_vendor_id[9] = "Linux   ";
+static char sdebug_inq_product_id[17] = "scsi_debug      ";
+static char sdebug_inq_product_rev[5] = SDEBUG_VERSION;
+/* Use some locally assigned NAAs for SAS addresses. */
+static const u64 naa3_comp_a = 0x3222222000000000ULL;
+static const u64 naa3_comp_b = 0x3333333000000000ULL;
+static const u64 naa3_comp_c = 0x3111111000000000ULL;
+
+/* Device identification VPD page. Returns number of bytes placed in arr */
+static int inquiry_vpd_83(unsigned char *arr, int port_group_id,
+			  int target_dev_id, int dev_id_num,
+			  const char *dev_id_str, int dev_id_str_len,
+			  const uuid_t *lu_name)
+{
+	int num, port_a;
+	char b[32];
+
+	port_a = target_dev_id + 1;
+	/* T10 vendor identifier field format (faked) */
+	arr[0] = 0x2;	/* ASCII */
+	arr[1] = 0x1;
+	arr[2] = 0x0;
+	memcpy(&arr[4], sdebug_inq_vendor_id, 8);
+	memcpy(&arr[12], sdebug_inq_product_id, 16);
+	memcpy(&arr[28], dev_id_str, dev_id_str_len);
+	num = 8 + 16 + dev_id_str_len;
+	arr[3] = num;
+	num += 4;
+	if (dev_id_num >= 0) {
+		if (sdebug_uuid_ctl) {
+			/* Locally assigned UUID */
+			arr[num++] = 0x1;  /* binary (not necessarily sas) */
+			arr[num++] = 0xa;  /* PIV=0, lu, naa */
+			arr[num++] = 0x0;
+			arr[num++] = 0x12;
+			arr[num++] = 0x10; /* uuid type=1, locally assigned */
+			arr[num++] = 0x0;
+			memcpy(arr + num, lu_name, 16);
+			num += 16;
+		} else {
+			/* NAA-3, Logical unit identifier (binary) */
+			arr[num++] = 0x1;  /* binary (not necessarily sas) */
+			arr[num++] = 0x3;  /* PIV=0, lu, naa */
+			arr[num++] = 0x0;
+			arr[num++] = 0x8;
+			put_unaligned_be64(naa3_comp_b + dev_id_num, arr + num);
+			num += 8;
+		}
+		/* Target relative port number */
+		arr[num++] = 0x61;	/* proto=sas, binary */
+		arr[num++] = 0x94;	/* PIV=1, target port, rel port */
+		arr[num++] = 0x0;	/* reserved */
+		arr[num++] = 0x4;	/* length */
+		arr[num++] = 0x0;	/* reserved */
+		arr[num++] = 0x0;	/* reserved */
+		arr[num++] = 0x0;
+		arr[num++] = 0x1;	/* relative port A */
+	}
+	/* NAA-3, Target port identifier */
+	arr[num++] = 0x61;	/* proto=sas, binary */
+	arr[num++] = 0x93;	/* piv=1, target port, naa */
+	arr[num++] = 0x0;
+	arr[num++] = 0x8;
+	put_unaligned_be64(naa3_comp_a + port_a, arr + num);
+	num += 8;
+	/* NAA-3, Target port group identifier */
+	arr[num++] = 0x61;	/* proto=sas, binary */
+	arr[num++] = 0x95;	/* piv=1, target port group id */
+	arr[num++] = 0x0;
+	arr[num++] = 0x4;
+	arr[num++] = 0;
+	arr[num++] = 0;
+	put_unaligned_be16(port_group_id, arr + num);
+	num += 2;
+	/* NAA-3, Target device identifier */
+	arr[num++] = 0x61;	/* proto=sas, binary */
+	arr[num++] = 0xa3;	/* piv=1, target device, naa */
+	arr[num++] = 0x0;
+	arr[num++] = 0x8;
+	put_unaligned_be64(naa3_comp_a + target_dev_id, arr + num);
+	num += 8;
+	/* SCSI name string: Target device identifier */
+	arr[num++] = 0x63;	/* proto=sas, UTF-8 */
+	arr[num++] = 0xa8;	/* piv=1, target device, SCSI name string */
+	arr[num++] = 0x0;
+	arr[num++] = 24;
+	memcpy(arr + num, "naa.32222220", 12);
+	num += 12;
+	snprintf(b, sizeof(b), "%08X", target_dev_id);
+	memcpy(arr + num, b, 8);
+	num += 8;
+	memset(arr + num, 0, 4);
+	num += 4;
+	return num;
+}
+
+static unsigned char vpd84_data[] = {
+/* from 4th byte */ 0x22,0x22,0x22,0x0,0xbb,0x0,
+    0x22,0x22,0x22,0x0,0xbb,0x1,
+    0x22,0x22,0x22,0x0,0xbb,0x2,
+};
+
+/*  Software interface identification VPD page */
+static int inquiry_vpd_84(unsigned char *arr)
+{
+	memcpy(arr, vpd84_data, sizeof(vpd84_data));
+	return sizeof(vpd84_data);
+}
+
+/* Management network addresses VPD page */
+static int inquiry_vpd_85(unsigned char *arr)
+{
+	int num = 0;
+	const char *na1 = "https://www.kernel.org/config";
+	const char *na2 = "http://www.kernel.org/log";
+	int plen, olen;
+
+	arr[num++] = 0x1;	/* lu, storage config */
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x0;
+	olen = strlen(na1);
+	plen = olen + 1;
+	if (plen % 4)
+		plen = ((plen / 4) + 1) * 4;
+	arr[num++] = plen;	/* length, null termianted, padded */
+	memcpy(arr + num, na1, olen);
+	memset(arr + num + olen, 0, plen - olen);
+	num += plen;
+
+	arr[num++] = 0x4;	/* lu, logging */
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x0;
+	olen = strlen(na2);
+	plen = olen + 1;
+	if (plen % 4)
+		plen = ((plen / 4) + 1) * 4;
+	arr[num++] = plen;	/* length, null terminated, padded */
+	memcpy(arr + num, na2, olen);
+	memset(arr + num + olen, 0, plen - olen);
+	num += plen;
+
+	return num;
+}
+
+/* SCSI ports VPD page */
+static int inquiry_vpd_88(unsigned char *arr, int target_dev_id)
+{
+	int num = 0;
+	int port_a, port_b;
+
+	port_a = target_dev_id + 1;
+	port_b = port_a + 1;
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x0;
+	arr[num++] = 0x1;	/* relative port 1 (primary) */
+	memset(arr + num, 0, 6);
+	num += 6;
+	arr[num++] = 0x0;
+	arr[num++] = 12;	/* length tp descriptor */
+	/* naa-5 target port identifier (A) */
+	arr[num++] = 0x61;	/* proto=sas, binary */
+	arr[num++] = 0x93;	/* PIV=1, target port, NAA */
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x8;	/* length */
+	put_unaligned_be64(naa3_comp_a + port_a, arr + num);
+	num += 8;
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x0;
+	arr[num++] = 0x2;	/* relative port 2 (secondary) */
+	memset(arr + num, 0, 6);
+	num += 6;
+	arr[num++] = 0x0;
+	arr[num++] = 12;	/* length tp descriptor */
+	/* naa-5 target port identifier (B) */
+	arr[num++] = 0x61;	/* proto=sas, binary */
+	arr[num++] = 0x93;	/* PIV=1, target port, NAA */
+	arr[num++] = 0x0;	/* reserved */
+	arr[num++] = 0x8;	/* length */
+	put_unaligned_be64(naa3_comp_a + port_b, arr + num);
+	num += 8;
+
+	return num;
+}
+
+
+static unsigned char vpd89_data[] = {
+/* from 4th byte */ 0,0,0,0,
+'l','i','n','u','x',' ',' ',' ',
+'S','A','T',' ','s','c','s','i','_','d','e','b','u','g',' ',' ',
+'1','2','3','4',
+0x34,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,
+0xec,0,0,0,
+0x5a,0xc,0xff,0x3f,0x37,0xc8,0x10,0,0,0,0,0,0x3f,0,0,0,
+0,0,0,0,0x58,0x58,0x58,0x58,0x58,0x58,0x58,0x58,0x20,0x20,0x20,0x20,
+0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0,0,0,0x40,0x4,0,0x2e,0x33,
+0x38,0x31,0x20,0x20,0x20,0x20,0x54,0x53,0x38,0x33,0x30,0x30,0x33,0x31,
+0x53,0x41,
+0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
+0x20,0x20,
+0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
+0x10,0x80,
+0,0,0,0x2f,0,0,0,0x2,0,0x2,0x7,0,0xff,0xff,0x1,0,
+0x3f,0,0xc1,0xff,0x3e,0,0x10,0x1,0xb0,0xf8,0x50,0x9,0,0,0x7,0,
+0x3,0,0x78,0,0x78,0,0xf0,0,0x78,0,0,0,0,0,0,0,
+0,0,0,0,0,0,0,0,0x2,0,0,0,0,0,0,0,
+0x7e,0,0x1b,0,0x6b,0x34,0x1,0x7d,0x3,0x40,0x69,0x34,0x1,0x3c,0x3,0x40,
+0x7f,0x40,0,0,0,0,0xfe,0xfe,0,0,0,0,0,0xfe,0,0,
+0,0,0,0,0,0,0,0,0xb0,0xf8,0x50,0x9,0,0,0,0,
+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,
+0x1,0,0xb0,0xf8,0x50,0x9,0xb0,0xf8,0x50,0x9,0x20,0x20,0x2,0,0xb6,0x42,
+0,0x80,0x8a,0,0x6,0x3c,0xa,0x3c,0xff,0xff,0xc6,0x7,0,0x1,0,0x8,
+0xf0,0xf,0,0x10,0x2,0,0x30,0,0,0,0,0,0,0,0x6,0xfe,
+0,0,0x2,0,0x50,0,0x8a,0,0x4f,0x95,0,0,0x21,0,0xb,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,
+0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+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,
+0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+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,
+0,0,0,0,0,0,0,0,0,0,0,0,0,0,0xa5,0x51,
+};
+
+/* ATA Information VPD page */
+static int inquiry_vpd_89(unsigned char *arr)
+{
+	memcpy(arr, vpd89_data, sizeof(vpd89_data));
+	return sizeof(vpd89_data);
+}
+
+
+static unsigned char vpdb0_data[] = {
+	/* from 4th byte */ 0,0,0,4, 0,0,0x4,0, 0,0,0,64,
+	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,
+};
+
+/* Block limits VPD page (SBC-3) */
+static int inquiry_vpd_b0(unsigned char *arr)
+{
+	unsigned int gran;
+
+	memcpy(arr, vpdb0_data, sizeof(vpdb0_data));
+
+	/* Optimal transfer length granularity */
+	if (sdebug_opt_xferlen_exp != 0 &&
+	    sdebug_physblk_exp < sdebug_opt_xferlen_exp)
+		gran = 1 << sdebug_opt_xferlen_exp;
+	else
+		gran = 1 << sdebug_physblk_exp;
+	put_unaligned_be16(gran, arr + 2);
+
+	/* Maximum Transfer Length */
+	if (sdebug_store_sectors > 0x400)
+		put_unaligned_be32(sdebug_store_sectors, arr + 4);
+
+	/* Optimal Transfer Length */
+	put_unaligned_be32(sdebug_opt_blks, &arr[8]);
+
+	if (sdebug_lbpu) {
+		/* Maximum Unmap LBA Count */
+		put_unaligned_be32(sdebug_unmap_max_blocks, &arr[16]);
+
+		/* Maximum Unmap Block Descriptor Count */
+		put_unaligned_be32(sdebug_unmap_max_desc, &arr[20]);
+	}
+
+	/* Unmap Granularity Alignment */
+	if (sdebug_unmap_alignment) {
+		put_unaligned_be32(sdebug_unmap_alignment, &arr[28]);
+		arr[28] |= 0x80; /* UGAVALID */
+	}
+
+	/* Optimal Unmap Granularity */
+	put_unaligned_be32(sdebug_unmap_granularity, &arr[24]);
+
+	/* Maximum WRITE SAME Length */
+	put_unaligned_be64(sdebug_write_same_length, &arr[32]);
+
+	return 0x3c; /* Mandatory page length for Logical Block Provisioning */
+
+	return sizeof(vpdb0_data);
+}
+
+/* Block device characteristics VPD page (SBC-3) */
+static int inquiry_vpd_b1(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" */
+
+	return 0x3c;
+}
+
+/* Logical block provisioning VPD page (SBC-4) */
+static int inquiry_vpd_b2(unsigned char *arr)
+{
+	memset(arr, 0, 0x4);
+	arr[0] = 0;			/* threshold exponent */
+	if (sdebug_lbpu)
+		arr[1] = 1 << 7;
+	if (sdebug_lbpws)
+		arr[1] |= 1 << 6;
+	if (sdebug_lbpws10)
+		arr[1] |= 1 << 5;
+	if (sdebug_lbprz && scsi_debug_lbp())
+		arr[1] |= (sdebug_lbprz & 0x7) << 2;  /* sbc4r07 and later */
+	/* anc_sup=0; dp=0 (no provisioning group descriptor) */
+	/* minimum_percentage=0; provisioning_type=0 (unknown) */
+	/* threshold_percentage=0 */
+	return 0x4;
+}
+
+#define SDEBUG_LONG_INQ_SZ 96
+#define SDEBUG_MAX_INQ_ARR_SZ 584
+
+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, is_disk;
+
+	alloc_len = get_unaligned_be16(cmd + 3);
+	arr = kzalloc(SDEBUG_MAX_INQ_ARR_SZ, GFP_ATOMIC);
+	if (! arr)
+		return DID_REQUEUE << 16;
+	is_disk = (sdebug_ptype == TYPE_DISK);
+	have_wlun = scsi_is_wlun(scp->device->lun);
+	if (have_wlun)
+		pq_pdt = TYPE_WLUN;	/* present, wlun */
+	else if (sdebug_no_lun_0 && (devip->lun == SDEBUG_LUN_0_VAL))
+		pq_pdt = 0x7f;	/* not present, PQ=3, PDT=0x1f */
+	else
+		pq_pdt = (sdebug_ptype & 0x1f);
+	arr[0] = pq_pdt;
+	if (0x2 & cmd[1]) {  /* CMDDT bit set */
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, 1);
+		kfree(arr);
+		return check_condition_result;
+	} else if (0x1 & cmd[1]) {  /* EVPD bit set */
+		int lu_id_num, port_group_id, target_dev_id, len;
+		char lu_id_str[6];
+		int host_no = devip->sdbg_host->shost->host_no;
+		
+		port_group_id = (((host_no + 1) & 0x7f) << 8) +
+		    (devip->channel & 0x7f);
+		if (sdebug_vpd_use_hostno == 0)
+			host_no = 0;
+		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;
+		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 */
+			arr[n++] = 0x83;  /* device identification */
+			arr[n++] = 0x84;  /* software interface ident. */
+			arr[n++] = 0x85;  /* management network addresses */
+			arr[n++] = 0x86;  /* extended inquiry */
+			arr[n++] = 0x87;  /* mode page policy */
+			arr[n++] = 0x88;  /* SCSI ports */
+			if (is_disk) {	  /* SBC only */
+				arr[n++] = 0x89;  /* ATA information */
+				arr[n++] = 0xb0;  /* Block limits */
+				arr[n++] = 0xb1;  /* Block characteristics */
+				arr[n++] = 0xb2;  /* Logical Block Prov */
+			}
+			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 */
+			else if (have_dif_prot)
+				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 */
+		} 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 && 0x89 == cmd[2]) { /* ATA information */
+			arr[1] = cmd[2];        /*sanity */
+			n = inquiry_vpd_89(&arr[4]);
+			put_unaligned_be16(n, arr + 2);
+		} else if (is_disk && 0xb0 == cmd[2]) { /* Block limits */
+			arr[1] = cmd[2];        /*sanity */
+			arr[3] = inquiry_vpd_b0(&arr[4]);
+		} else if (is_disk && 0xb1 == cmd[2]) { /* Block char. */
+			arr[1] = cmd[2];        /*sanity */
+			arr[3] = inquiry_vpd_b1(&arr[4]);
+		} else if (is_disk && 0xb2 == cmd[2]) { /* LB Prov. */
+			arr[1] = cmd[2];        /*sanity */
+			arr[3] = inquiry_vpd_b2(&arr[4]);
+		} else {
+			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, -1);
+			kfree(arr);
+			return check_condition_result;
+		}
+		len = min(get_unaligned_be16(arr + 2) + 4, alloc_len);
+		ret = fill_from_dev_buffer(scp, arr,
+			    min(len, SDEBUG_MAX_INQ_ARR_SZ));
+		kfree(arr);
+		return ret;
+	}
+	/* drops through here for a standard inquiry */
+	arr[1] = sdebug_removable ? 0x80 : 0;	/* Removable disk */
+	arr[2] = sdebug_scsi_level;
+	arr[3] = 2;    /* response_data_format==2 */
+	arr[4] = SDEBUG_LONG_INQ_SZ - 5;
+	arr[5] = (int)have_dif_prot;	/* PROTECT bit */
+	if (sdebug_vpd_use_hostno == 0)
+		arr[5] |= 0x10; /* claim: implicit TPGS */
+	arr[6] = 0x10; /* claim: MultiP */
+	/* arr[6] |= 0x40; ... claim: EncServ (enclosure services) */
+	arr[7] = 0xa; /* claim: LINKED + CMDQUE */
+	memcpy(&arr[8], sdebug_inq_vendor_id, 8);
+	memcpy(&arr[16], sdebug_inq_product_id, 16);
+	memcpy(&arr[32], sdebug_inq_product_rev, 4);
+	/* Use Vendor Specific area to place driver date in ASCII hex */
+	memcpy(&arr[36], sdebug_version_date, 8);
+	/* version descriptors (2 bytes each) follow */
+	put_unaligned_be16(0xc0, arr + 58);   /* SAM-6 no version claimed */
+	put_unaligned_be16(0x5c0, arr + 60);  /* SPC-5 no version claimed */
+	n = 62;
+	if (is_disk) {		/* SBC-4 no version claimed */
+		put_unaligned_be16(0x600, arr + n);
+		n += 2;
+	} else if (sdebug_ptype == TYPE_TAPE) {	/* SSC-4 rev 3 */
+		put_unaligned_be16(0x525, arr + n);
+		n += 2;
+	}
+	put_unaligned_be16(0x2100, arr + n);	/* SPL-4 no version claimed */
+	ret = fill_from_dev_buffer(scp, arr,
+			    min(alloc_len, SDEBUG_LONG_INQ_SZ));
+	kfree(arr);
+	return ret;
+}
+
+static unsigned char iec_m_pg[] = {0x1c, 0xa, 0x08, 0, 0, 0, 0, 0,
+				   0, 0, 0x0, 0x0};
+
+static int resp_requests(struct scsi_cmnd *scp,
+			 struct sdebug_dev_info *devip)
+{
+	unsigned char *sbuff;
+	unsigned char *cmd = scp->cmnd;
+	unsigned char arr[SCSI_SENSE_BUFFERSIZE];
+	bool dsense;
+	int len = 18;
+
+	memset(arr, 0, sizeof(arr));
+	dsense = !!(cmd[1] & 1);
+	sbuff = scp->sense_buffer;
+	if ((iec_m_pg[2] & 0x4) && (6 == (iec_m_pg[3] & 0xf))) {
+		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 */
+			arr[7] = 0xa;   	/* 18 byte sense buffer */
+			arr[12] = THRESHOLD_EXCEEDED;
+			arr[13] = 0xff;		/* TEST set and MRIE==6 */
+		}
+	} else {
+		memcpy(arr, sbuff, SCSI_SENSE_BUFFERSIZE);
+		if (arr[0] >= 0x70 && dsense == sdebug_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);
+}
+
+static int resp_start_stop(struct scsi_cmnd *scp,
+			   struct sdebug_dev_info *devip)
+{
+	unsigned char *cmd = scp->cmnd;
+	int power_cond, stop;
+	bool changing;
+
+	power_cond = (cmd[4] & 0xf0) >> 4;
+	if (power_cond) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, 7);
+		return check_condition_result;
+	}
+	stop = !(cmd[4] & 1);
+	changing = atomic_read(&devip->stopped) == !stop;
+	atomic_xchg(&devip->stopped, stop);
+	if (!changing || cmd[1] & 0x1)  /* state unchanged or IMMED set */
+		return SDEG_RES_IMMED_MASK;
+	else
+		return 0;
+}
+
+static sector_t get_sdebug_capacity(void)
+{
+	static const unsigned int gibibyte = 1073741824;
+
+	if (sdebug_virtual_gb > 0)
+		return (sector_t)sdebug_virtual_gb *
+			(gibibyte / sdebug_sector_size);
+	else
+		return sdebug_store_sectors;
+}
+
+#define SDEBUG_READCAP_ARR_SZ 8
+static int resp_readcap(struct scsi_cmnd *scp,
+			struct sdebug_dev_info *devip)
+{
+	unsigned char arr[SDEBUG_READCAP_ARR_SZ];
+	unsigned int capac;
+
+	/* following just in case virtual_gb changed */
+	sdebug_capacity = get_sdebug_capacity();
+	memset(arr, 0, SDEBUG_READCAP_ARR_SZ);
+	if (sdebug_capacity < 0xffffffff) {
+		capac = (unsigned int)sdebug_capacity - 1;
+		put_unaligned_be32(capac, arr + 0);
+	} else
+		put_unaligned_be32(0xffffffff, arr + 0);
+	put_unaligned_be16(sdebug_sector_size, arr + 6);
+	return fill_from_dev_buffer(scp, arr, SDEBUG_READCAP_ARR_SZ);
+}
+
+#define SDEBUG_READCAP16_ARR_SZ 32
+static int resp_readcap16(struct scsi_cmnd *scp,
+			  struct sdebug_dev_info *devip)
+{
+	unsigned char *cmd = scp->cmnd;
+	unsigned char arr[SDEBUG_READCAP16_ARR_SZ];
+	int alloc_len;
+
+	alloc_len = get_unaligned_be32(cmd + 10);
+	/* following just in case virtual_gb changed */
+	sdebug_capacity = get_sdebug_capacity();
+	memset(arr, 0, SDEBUG_READCAP16_ARR_SZ);
+	put_unaligned_be64((u64)(sdebug_capacity - 1), arr + 0);
+	put_unaligned_be32(sdebug_sector_size, arr + 8);
+	arr[13] = sdebug_physblk_exp & 0xf;
+	arr[14] = (sdebug_lowest_aligned >> 8) & 0x3f;
+
+	if (scsi_debug_lbp()) {
+		arr[14] |= 0x80; /* LBPME */
+		/* from sbc4r07, this LBPRZ field is 1 bit, but the LBPRZ in
+		 * the LB Provisioning VPD page is 3 bits. Note that lbprz=2
+		 * in the wider field maps to 0 in this field.
+		 */
+		if (sdebug_lbprz & 1)	/* precisely what the draft requires */
+			arr[14] |= 0x40;
+	}
+
+	arr[15] = sdebug_lowest_aligned & 0xff;
+
+	if (have_dif_prot) {
+		arr[12] = (sdebug_dif - 1) << 1; /* P_TYPE */
+		arr[12] |= 1; /* PROT_EN */
+	}
+
+	return fill_from_dev_buffer(scp, arr,
+				    min(alloc_len, SDEBUG_READCAP16_ARR_SZ));
+}
+
+#define SDEBUG_MAX_TGTPGS_ARR_SZ 1412
+
+static int resp_report_tgtpgs(struct scsi_cmnd *scp,
+			      struct sdebug_dev_info *devip)
+{
+	unsigned char *cmd = scp->cmnd;
+	unsigned char *arr;
+	int host_no = devip->sdbg_host->shost->host_no;
+	int n, ret, alen, rlen;
+	int port_group_a, port_group_b, port_a, port_b;
+
+	alen = get_unaligned_be32(cmd + 6);
+	arr = kzalloc(SDEBUG_MAX_TGTPGS_ARR_SZ, GFP_ATOMIC);
+	if (! arr)
+		return DID_REQUEUE << 16;
+	/*
+	 * EVPD page 0x88 states we have two ports, one
+	 * real and a fake port with no device connected.
+	 * So we create two port groups with one port each
+	 * and set the group with port B to unavailable.
+	 */
+	port_a = 0x1; /* relative port A */
+	port_b = 0x2; /* relative port B */
+	port_group_a = (((host_no + 1) & 0x7f) << 8) +
+			(devip->channel & 0x7f);
+	port_group_b = (((host_no + 1) & 0x7f) << 8) +
+			(devip->channel & 0x7f) + 0x80;
+
+	/*
+	 * The asymmetric access state is cycled according to the host_id.
+	 */
+	n = 4;
+	if (sdebug_vpd_use_hostno == 0) {
+		arr[n++] = host_no % 3; /* Asymm access state */
+		arr[n++] = 0x0F; /* claim: all states are supported */
+	} else {
+		arr[n++] = 0x0; /* Active/Optimized path */
+		arr[n++] = 0x01; /* only support active/optimized paths */
+	}
+	put_unaligned_be16(port_group_a, arr + n);
+	n += 2;
+	arr[n++] = 0;    /* Reserved */
+	arr[n++] = 0;    /* Status code */
+	arr[n++] = 0;    /* Vendor unique */
+	arr[n++] = 0x1;  /* One port per group */
+	arr[n++] = 0;    /* Reserved */
+	arr[n++] = 0;    /* Reserved */
+	put_unaligned_be16(port_a, arr + n);
+	n += 2;
+	arr[n++] = 3;    /* Port unavailable */
+	arr[n++] = 0x08; /* claim: only unavailalbe paths are supported */
+	put_unaligned_be16(port_group_b, arr + n);
+	n += 2;
+	arr[n++] = 0;    /* Reserved */
+	arr[n++] = 0;    /* Status code */
+	arr[n++] = 0;    /* Vendor unique */
+	arr[n++] = 0x1;  /* One port per group */
+	arr[n++] = 0;    /* Reserved */
+	arr[n++] = 0;    /* Reserved */
+	put_unaligned_be16(port_b, arr + n);
+	n += 2;
+
+	rlen = n - 4;
+	put_unaligned_be32(rlen, arr + 0);
+
+	/*
+	 * Return the smallest value of either
+	 * - The allocated length
+	 * - The constructed command length
+	 * - The maximum array size
+	 */
+	rlen = min(alen,n);
+	ret = fill_from_dev_buffer(scp, arr,
+				   min(rlen, SDEBUG_MAX_TGTPGS_ARR_SZ));
+	kfree(arr);
+	return ret;
+}
+
+static int resp_rsup_opcodes(struct scsi_cmnd *scp,
+			     struct sdebug_dev_info *devip)
+{
+	bool rctd;
+	u8 reporting_opts, req_opcode, sdeb_i, supp;
+	u16 req_sa, u;
+	u32 alloc_len, a_len;
+	int k, offset, len, errsts, count, bump, na;
+	const struct opcode_info_t *oip;
+	const struct opcode_info_t *r_oip;
+	u8 *arr;
+	u8 *cmd = scp->cmnd;
+
+	rctd = !!(cmd[2] & 0x80);
+	reporting_opts = cmd[2] & 0x7;
+	req_opcode = cmd[3];
+	req_sa = get_unaligned_be16(cmd + 4);
+	alloc_len = get_unaligned_be32(cmd + 6);
+	if (alloc_len < 4 || alloc_len > 0xffff) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 6, -1);
+		return check_condition_result;
+	}
+	if (alloc_len > 8192)
+		a_len = 8192;
+	else
+		a_len = alloc_len;
+	arr = kzalloc((a_len < 256) ? 320 : a_len + 64, GFP_ATOMIC);
+	if (NULL == arr) {
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
+				INSUFF_RES_ASCQ);
+		return check_condition_result;
+	}
+	switch (reporting_opts) {
+	case 0:	/* all commands */
+		/* count number of commands */
+		for (count = 0, oip = opcode_info_arr;
+		     oip->num_attached != 0xff; ++oip) {
+			if (F_INV_OP & oip->flags)
+				continue;
+			count += (oip->num_attached + 1);
+		}
+		bump = rctd ? 20 : 8;
+		put_unaligned_be32(count * bump, arr);
+		for (offset = 4, oip = opcode_info_arr;
+		     oip->num_attached != 0xff && offset < a_len; ++oip) {
+			if (F_INV_OP & oip->flags)
+				continue;
+			na = oip->num_attached;
+			arr[offset] = oip->opcode;
+			put_unaligned_be16(oip->sa, arr + offset + 2);
+			if (rctd)
+				arr[offset + 5] |= 0x2;
+			if (FF_SA & oip->flags)
+				arr[offset + 5] |= 0x1;
+			put_unaligned_be16(oip->len_mask[0], arr + offset + 6);
+			if (rctd)
+				put_unaligned_be16(0xa, arr + offset + 8);
+			r_oip = oip;
+			for (k = 0, oip = oip->arrp; k < na; ++k, ++oip) {
+				if (F_INV_OP & oip->flags)
+					continue;
+				offset += bump;
+				arr[offset] = oip->opcode;
+				put_unaligned_be16(oip->sa, arr + offset + 2);
+				if (rctd)
+					arr[offset + 5] |= 0x2;
+				if (FF_SA & oip->flags)
+					arr[offset + 5] |= 0x1;
+				put_unaligned_be16(oip->len_mask[0],
+						   arr + offset + 6);
+				if (rctd)
+					put_unaligned_be16(0xa,
+							   arr + offset + 8);
+			}
+			oip = r_oip;
+			offset += bump;
+		}
+		break;
+	case 1:	/* one command: opcode only */
+	case 2:	/* one command: opcode plus service action */
+	case 3:	/* one command: if sa==0 then opcode only else opcode+sa */
+		sdeb_i = opcode_ind_arr[req_opcode];
+		oip = &opcode_info_arr[sdeb_i];
+		if (F_INV_OP & oip->flags) {
+			supp = 1;
+			offset = 4;
+		} else {
+			if (1 == reporting_opts) {
+				if (FF_SA & oip->flags) {
+					mk_sense_invalid_fld(scp, SDEB_IN_CDB,
+							     2, 2);
+					kfree(arr);
+					return check_condition_result;
+				}
+				req_sa = 0;
+			} else if (2 == reporting_opts &&
+				   0 == (FF_SA & oip->flags)) {
+				mk_sense_invalid_fld(scp, SDEB_IN_CDB, 4, -1);
+				kfree(arr);	/* point at requested sa */
+				return check_condition_result;
+			}
+			if (0 == (FF_SA & oip->flags) &&
+			    req_opcode == oip->opcode)
+				supp = 3;
+			else if (0 == (FF_SA & oip->flags)) {
+				na = oip->num_attached;
+				for (k = 0, oip = oip->arrp; k < na;
+				     ++k, ++oip) {
+					if (req_opcode == oip->opcode)
+						break;
+				}
+				supp = (k >= na) ? 1 : 3;
+			} else if (req_sa != oip->sa) {
+				na = oip->num_attached;
+				for (k = 0, oip = oip->arrp; k < na;
+				     ++k, ++oip) {
+					if (req_sa == oip->sa)
+						break;
+				}
+				supp = (k >= na) ? 1 : 3;
+			} else
+				supp = 3;
+			if (3 == supp) {
+				u = oip->len_mask[0];
+				put_unaligned_be16(u, arr + 2);
+				arr[4] = oip->opcode;
+				for (k = 1; k < u; ++k)
+					arr[4 + k] = (k < 16) ?
+						 oip->len_mask[k] : 0xff;
+				offset = 4 + u;
+			} else
+				offset = 4;
+		}
+		arr[1] = (rctd ? 0x80 : 0) | supp;
+		if (rctd) {
+			put_unaligned_be16(0xa, arr + offset);
+			offset += 12;
+		}
+		break;
+	default:
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 2);
+		kfree(arr);
+		return check_condition_result;
+	}
+	offset = (offset < a_len) ? offset : a_len;
+	len = (offset < alloc_len) ? offset : alloc_len;
+	errsts = fill_from_dev_buffer(scp, arr, len);
+	kfree(arr);
+	return errsts;
+}
+
+static int resp_rsup_tmfs(struct scsi_cmnd *scp,
+			  struct sdebug_dev_info *devip)
+{
+	bool repd;
+	u32 alloc_len, len;
+	u8 arr[16];
+	u8 *cmd = scp->cmnd;
+
+	memset(arr, 0, sizeof(arr));
+	repd = !!(cmd[2] & 0x80);
+	alloc_len = get_unaligned_be32(cmd + 6);
+	if (alloc_len < 4) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 6, -1);
+		return check_condition_result;
+	}
+	arr[0] = 0xc8;		/* ATS | ATSS | LURS */
+	arr[1] = 0x1;		/* ITNRS */
+	if (repd) {
+		arr[3] = 0xc;
+		len = 16;
+	} else
+		len = 4;
+
+	len = (len < alloc_len) ? len : alloc_len;
+	return fill_from_dev_buffer(scp, arr, len);
+}
+
+/* <<Following mode page info copied from ST318451LW>> */
+
+static int resp_err_recov_pg(unsigned char *p, int pcontrol, int target)
+{	/* Read-Write Error Recovery page for mode_sense */
+	unsigned char err_recov_pg[] = {0x1, 0xa, 0xc0, 11, 240, 0, 0, 0,
+					5, 0, 0xff, 0xff};
+
+	memcpy(p, err_recov_pg, sizeof(err_recov_pg));
+	if (1 == pcontrol)
+		memset(p + 2, 0, sizeof(err_recov_pg) - 2);
+	return sizeof(err_recov_pg);
+}
+
+static int resp_disconnect_pg(unsigned char *p, int pcontrol, int target)
+{ 	/* Disconnect-Reconnect page for mode_sense */
+	unsigned char disconnect_pg[] = {0x2, 0xe, 128, 128, 0, 10, 0, 0,
+					 0, 0, 0, 0, 0, 0, 0, 0};
+
+	memcpy(p, disconnect_pg, sizeof(disconnect_pg));
+	if (1 == pcontrol)
+		memset(p + 2, 0, sizeof(disconnect_pg) - 2);
+	return sizeof(disconnect_pg);
+}
+
+static int resp_format_pg(unsigned char *p, int pcontrol, int target)
+{       /* Format device page for mode_sense */
+	unsigned char format_pg[] = {0x3, 0x16, 0, 0, 0, 0, 0, 0,
+				     0, 0, 0, 0, 0, 0, 0, 0,
+				     0, 0, 0, 0, 0x40, 0, 0, 0};
+
+	memcpy(p, format_pg, sizeof(format_pg));
+	put_unaligned_be16(sdebug_sectors_per, p + 10);
+	put_unaligned_be16(sdebug_sector_size, p + 12);
+	if (sdebug_removable)
+		p[20] |= 0x20; /* should agree with INQUIRY */
+	if (1 == pcontrol)
+		memset(p + 2, 0, sizeof(format_pg) - 2);
+	return sizeof(format_pg);
+}
+
+static unsigned char caching_pg[] = {0x8, 18, 0x14, 0, 0xff, 0xff, 0, 0,
+				     0xff, 0xff, 0xff, 0xff, 0x80, 0x14, 0, 0,
+				     0, 0, 0, 0};
+
+static int resp_caching_pg(unsigned char *p, int pcontrol, int target)
+{ 	/* Caching page for mode_sense */
+	unsigned char ch_caching_pg[] = {/* 0x8, 18, */ 0x4, 0, 0, 0, 0, 0,
+		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+	unsigned char d_caching_pg[] = {0x8, 18, 0x14, 0, 0xff, 0xff, 0, 0,
+		0xff, 0xff, 0xff, 0xff, 0x80, 0x14, 0, 0,     0, 0, 0, 0};
+
+	if (SDEBUG_OPT_N_WCE & sdebug_opts)
+		caching_pg[2] &= ~0x4;	/* set WCE=0 (default WCE=1) */
+	memcpy(p, caching_pg, sizeof(caching_pg));
+	if (1 == pcontrol)
+		memcpy(p + 2, ch_caching_pg, sizeof(ch_caching_pg));
+	else if (2 == pcontrol)
+		memcpy(p, d_caching_pg, sizeof(d_caching_pg));
+	return sizeof(caching_pg);
+}
+
+static unsigned char ctrl_m_pg[] = {0xa, 10, 2, 0, 0, 0, 0, 0,
+				    0, 0, 0x2, 0x4b};
+
+static int resp_ctrl_m_pg(unsigned char *p, int pcontrol, int target)
+{ 	/* Control mode page for mode_sense */
+	unsigned char ch_ctrl_m_pg[] = {/* 0xa, 10, */ 0x6, 0, 0, 0, 0, 0,
+					0, 0, 0, 0};
+	unsigned char d_ctrl_m_pg[] = {0xa, 10, 2, 0, 0, 0, 0, 0,
+				     0, 0, 0x2, 0x4b};
+
+	if (sdebug_dsense)
+		ctrl_m_pg[2] |= 0x4;
+	else
+		ctrl_m_pg[2] &= ~0x4;
+
+	if (sdebug_ato)
+		ctrl_m_pg[5] |= 0x80; /* ATO=1 */
+
+	memcpy(p, ctrl_m_pg, sizeof(ctrl_m_pg));
+	if (1 == pcontrol)
+		memcpy(p + 2, ch_ctrl_m_pg, sizeof(ch_ctrl_m_pg));
+	else if (2 == pcontrol)
+		memcpy(p, d_ctrl_m_pg, sizeof(d_ctrl_m_pg));
+	return sizeof(ctrl_m_pg);
+}
+
+
+static int resp_iec_m_pg(unsigned char *p, int pcontrol, int target)
+{	/* Informational Exceptions control mode page for mode_sense */
+	unsigned char ch_iec_m_pg[] = {/* 0x1c, 0xa, */ 0x4, 0xf, 0, 0, 0, 0,
+				       0, 0, 0x0, 0x0};
+	unsigned char d_iec_m_pg[] = {0x1c, 0xa, 0x08, 0, 0, 0, 0, 0,
+				      0, 0, 0x0, 0x0};
+
+	memcpy(p, iec_m_pg, sizeof(iec_m_pg));
+	if (1 == pcontrol)
+		memcpy(p + 2, ch_iec_m_pg, sizeof(ch_iec_m_pg));
+	else if (2 == pcontrol)
+		memcpy(p, d_iec_m_pg, sizeof(d_iec_m_pg));
+	return sizeof(iec_m_pg);
+}
+
+static int resp_sas_sf_m_pg(unsigned char *p, int pcontrol, int target)
+{	/* SAS SSP mode page - short format for mode_sense */
+	unsigned char sas_sf_m_pg[] = {0x19, 0x6,
+		0x6, 0x0, 0x7, 0xd0, 0x0, 0x0};
+
+	memcpy(p, sas_sf_m_pg, sizeof(sas_sf_m_pg));
+	if (1 == pcontrol)
+		memset(p + 2, 0, sizeof(sas_sf_m_pg) - 2);
+	return sizeof(sas_sf_m_pg);
+}
+
+
+static int resp_sas_pcd_m_spg(unsigned char *p, int pcontrol, int target,
+			      int target_dev_id)
+{	/* SAS phy control and discover mode page for mode_sense */
+	unsigned char sas_pcd_m_pg[] = {0x59, 0x1, 0, 0x64, 0, 0x6, 0, 2,
+		    0, 0, 0, 0, 0x10, 0x9, 0x8, 0x0,
+		    0, 0, 0, 0, 0, 0, 0, 0,	/* insert SAS addr */
+		    0, 0, 0, 0, 0, 0, 0, 0,	/* insert SAS addr */
+		    0x2, 0, 0, 0, 0, 0, 0, 0,
+		    0x88, 0x99, 0, 0, 0, 0, 0, 0,
+		    0, 0, 0, 0, 0, 0, 0, 0,
+		    0, 1, 0, 0, 0x10, 0x9, 0x8, 0x0,
+		    0, 0, 0, 0, 0, 0, 0, 0,	/* insert SAS addr */
+		    0, 0, 0, 0, 0, 0, 0, 0,	/* insert SAS addr */
+		    0x3, 0, 0, 0, 0, 0, 0, 0,
+		    0x88, 0x99, 0, 0, 0, 0, 0, 0,
+		    0, 0, 0, 0, 0, 0, 0, 0,
+		};
+	int port_a, port_b;
+
+	put_unaligned_be64(naa3_comp_a, sas_pcd_m_pg + 16);
+	put_unaligned_be64(naa3_comp_c + 1, sas_pcd_m_pg + 24);
+	put_unaligned_be64(naa3_comp_a, sas_pcd_m_pg + 64);
+	put_unaligned_be64(naa3_comp_c + 1, sas_pcd_m_pg + 72);
+	port_a = target_dev_id + 1;
+	port_b = port_a + 1;
+	memcpy(p, sas_pcd_m_pg, sizeof(sas_pcd_m_pg));
+	put_unaligned_be32(port_a, p + 20);
+	put_unaligned_be32(port_b, p + 48 + 20);
+	if (1 == pcontrol)
+		memset(p + 4, 0, sizeof(sas_pcd_m_pg) - 4);
+	return sizeof(sas_pcd_m_pg);
+}
+
+static int resp_sas_sha_m_spg(unsigned char *p, int pcontrol)
+{	/* SAS SSP shared protocol specific port mode subpage */
+	unsigned char sas_sha_m_pg[] = {0x59, 0x2, 0, 0xc, 0, 0x6, 0x10, 0,
+		    0, 0, 0, 0, 0, 0, 0, 0,
+		};
+
+	memcpy(p, sas_sha_m_pg, sizeof(sas_sha_m_pg));
+	if (1 == pcontrol)
+		memset(p + 4, 0, sizeof(sas_sha_m_pg) - 4);
+	return sizeof(sas_sha_m_pg);
+}
+
+#define SDEBUG_MAX_MSENSE_SZ 256
+
+static int resp_mode_sense(struct scsi_cmnd *scp,
+			   struct sdebug_dev_info *devip)
+{
+	int pcontrol, pcode, subpcode, bd_len;
+	unsigned char dev_spec;
+	int alloc_len, 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;
+	bool dbd, llbaa, msense_6, is_disk, bad_pcode;
+
+	dbd = !!(cmd[1] & 0x8);		/* disable block descriptors */
+	pcontrol = (cmd[2] & 0xc0) >> 6;
+	pcode = cmd[2] & 0x3f;
+	subpcode = cmd[3];
+	msense_6 = (MODE_SENSE == cmd[0]);
+	llbaa = msense_6 ? false : !!(cmd[1] & 0x10);
+	is_disk = (sdebug_ptype == TYPE_DISK);
+	if (is_disk && !dbd)
+		bd_len = llbaa ? 16 : 8;
+	else
+		bd_len = 0;
+	alloc_len = msense_6 ? cmd[4] : get_unaligned_be16(cmd + 7);
+	memset(arr, 0, SDEBUG_MAX_MSENSE_SZ);
+	if (0x3 == pcontrol) {  /* Saving values not supported */
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, SAVING_PARAMS_UNSUP, 0);
+		return check_condition_result;
+	}
+	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)
+		dev_spec = 0x10;	/* =0x90 if WP=1 implies read-only */
+	else
+		dev_spec = 0x0;
+	if (msense_6) {
+		arr[2] = dev_spec;
+		arr[3] = bd_len;
+		offset = 4;
+	} else {
+		arr[3] = dev_spec;
+		if (16 == bd_len)
+			arr[4] = 0x1;	/* set LONGLBA bit */
+		arr[7] = bd_len;	/* assume 255 or less */
+		offset = 8;
+	}
+	ap = arr + offset;
+	if ((bd_len > 0) && (!sdebug_capacity))
+		sdebug_capacity = get_sdebug_capacity();
+
+	if (8 == bd_len) {
+		if (sdebug_capacity > 0xfffffffe)
+			put_unaligned_be32(0xffffffff, ap + 0);
+		else
+			put_unaligned_be32(sdebug_capacity, ap + 0);
+		put_unaligned_be16(sdebug_sector_size, ap + 6);
+		offset += bd_len;
+		ap = arr + offset;
+	} else if (16 == bd_len) {
+		put_unaligned_be64((u64)sdebug_capacity, ap + 0);
+		put_unaligned_be32(sdebug_sector_size, ap + 12);
+		offset += bd_len;
+		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;
+
+	switch (pcode) {
+	case 0x1:	/* Read-Write error recovery page, direct access */
+		len = resp_err_recov_pg(ap, pcontrol, target);
+		offset += len;
+		break;
+	case 0x2:	/* Disconnect-Reconnect page, all devices */
+		len = resp_disconnect_pg(ap, pcontrol, target);
+		offset += len;
+		break;
+	case 0x3:       /* Format device page, direct access */
+		if (is_disk) {
+			len = resp_format_pg(ap, pcontrol, target);
+			offset += len;
+		} else
+			bad_pcode = true;
+		break;
+	case 0x8:	/* Caching page, direct access */
+		if (is_disk) {
+			len = resp_caching_pg(ap, pcontrol, target);
+			offset += len;
+		} else
+			bad_pcode = true;
+		break;
+	case 0xa:	/* Control Mode page, all devices */
+		len = resp_ctrl_m_pg(ap, pcontrol, target);
+		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;
+		}
+		len = 0;
+		if ((0x0 == subpcode) || (0xff == subpcode))
+			len += resp_sas_sf_m_pg(ap + len, pcontrol, target);
+		if ((0x1 == subpcode) || (0xff == subpcode))
+			len += resp_sas_pcd_m_spg(ap + len, pcontrol, target,
+						  target_dev_id);
+		if ((0x2 == subpcode) || (0xff == subpcode))
+			len += resp_sas_sha_m_spg(ap + len, pcontrol);
+		offset += len;
+		break;
+	case 0x1c:	/* Informational Exceptions Mode page, all devices */
+		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);
+			}
+			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;
+		}
+		break;
+	default:
+		bad_pcode = true;
+		break;
+	}
+	if (bad_pcode) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
+		return check_condition_result;
+	}
+	if (msense_6)
+		arr[0] = offset - 1;
+	else
+		put_unaligned_be16((offset - 2), arr + 0);
+	return fill_from_dev_buffer(scp, arr, min(alloc_len, offset));
+}
+
+#define SDEBUG_MAX_MSELECT_SZ 512
+
+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, mpage;
+	unsigned char arr[SDEBUG_MAX_MSELECT_SZ];
+	unsigned char *cmd = scp->cmnd;
+	int mselect6 = (MODE_SELECT == cmd[0]);
+
+	memset(arr, 0, sizeof(arr));
+	pf = cmd[1] & 0x10;
+	sp = cmd[1] & 0x1;
+	param_len = mselect6 ? cmd[4] : get_unaligned_be16(cmd + 7);
+	if ((0 == pf) || sp || (param_len > SDEBUG_MAX_MSELECT_SZ)) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, mselect6 ? 4 : 7, -1);
+		return check_condition_result;
+	}
+	res = fetch_to_dev_buffer(scp, arr, param_len);
+	if (-1 == res)
+		return DID_ERROR << 16;
+	else if (sdebug_verbose && (res < param_len))
+		sdev_printk(KERN_INFO, scp->device,
+			    "%s: cdb indicated=%d, IO sent=%d bytes\n",
+			    __func__, param_len, res);
+	md_len = mselect6 ? (arr[0] + 1) : (get_unaligned_be16(arr + 0) + 2);
+	bd_len = mselect6 ? arr[3] : get_unaligned_be16(arr + 6);
+	off = bd_len + (mselect6 ? 4 : 8);
+	if (md_len > 2 || off >= res) {
+		mk_sense_invalid_fld(scp, SDEB_IN_DATA, 0, -1);
+		return check_condition_result;
+	}
+	mpage = arr[off] & 0x3f;
+	ps = !!(arr[off] & 0x80);
+	if (ps) {
+		mk_sense_invalid_fld(scp, SDEB_IN_DATA, off, 7);
+		return check_condition_result;
+	}
+	spf = !!(arr[off] & 0x40);
+	pg_len = spf ? (get_unaligned_be16(arr + off + 2) + 4) :
+		       (arr[off + 1] + 2);
+	if ((pg_len + off) > param_len) {
+		mk_sense_buffer(scp, ILLEGAL_REQUEST,
+				PARAMETER_LIST_LENGTH_ERR, 0);
+		return check_condition_result;
+	}
+	switch (mpage) {
+	case 0x8:      /* Caching Mode page */
+		if (caching_pg[1] == arr[off + 1]) {
+			memcpy(caching_pg + 2, arr + off + 2,
+			       sizeof(caching_pg) - 2);
+			goto set_mode_changed_ua;
+		}
+		break;
+	case 0xa:      /* Control Mode page */
+		if (ctrl_m_pg[1] == arr[off + 1]) {
+			memcpy(ctrl_m_pg + 2, arr + off + 2,
+			       sizeof(ctrl_m_pg) - 2);
+			sdebug_dsense = !!(ctrl_m_pg[2] & 0x4);
+			goto set_mode_changed_ua;
+		}
+		break;
+	case 0x1c:      /* Informational Exceptions Mode page */
+		if (iec_m_pg[1] == arr[off + 1]) {
+			memcpy(iec_m_pg + 2, arr + off + 2,
+			       sizeof(iec_m_pg) - 2);
+			goto set_mode_changed_ua;
+		}
+		break;
+	default:
+		break;
+	}
+	mk_sense_invalid_fld(scp, SDEB_IN_DATA, off, 5);
+	return check_condition_result;
+set_mode_changed_ua:
+	set_bit(SDEBUG_UA_MODE_CHANGED, devip->uas_bm);
+	return 0;
+}
+
+static int resp_temp_l_pg(unsigned char *arr)
+{
+	unsigned char temp_l_pg[] = {0x0, 0x0, 0x3, 0x2, 0x0, 38,
+				     0x0, 0x1, 0x3, 0x2, 0x0, 65,
+		};
+
+	memcpy(arr, temp_l_pg, sizeof(temp_l_pg));
+	return sizeof(temp_l_pg);
+}
+
+static int resp_ie_l_pg(unsigned char *arr)
+{
+	unsigned char ie_l_pg[] = {0x0, 0x0, 0x3, 0x3, 0x0, 0x0, 38,
+		};
+
+	memcpy(arr, ie_l_pg, sizeof(ie_l_pg));
+	if (iec_m_pg[2] & 0x4) {	/* TEST bit set */
+		arr[4] = THRESHOLD_EXCEEDED;
+		arr[5] = 0xff;
+	}
+	return sizeof(ie_l_pg);
+}
+
+#define SDEBUG_MAX_LSENSE_SZ 512
+
+static int resp_log_sense(struct scsi_cmnd *scp,
+			  struct sdebug_dev_info *devip)
+{
+	int ppc, sp, pcode, subpcode, alloc_len, len, n;
+	unsigned char arr[SDEBUG_MAX_LSENSE_SZ];
+	unsigned char *cmd = scp->cmnd;
+
+	memset(arr, 0, sizeof(arr));
+	ppc = cmd[1] & 0x2;
+	sp = cmd[1] & 0x1;
+	if (ppc || sp) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 1, ppc ? 1 : 0);
+		return check_condition_result;
+	}
+	pcode = cmd[2] & 0x3f;
+	subpcode = cmd[3] & 0xff;
+	alloc_len = get_unaligned_be16(cmd + 7);
+	arr[0] = pcode;
+	if (0 == subpcode) {
+		switch (pcode) {
+		case 0x0:	/* Supported log pages log page */
+			n = 4;
+			arr[n++] = 0x0;		/* this page */
+			arr[n++] = 0xd;		/* Temperature */
+			arr[n++] = 0x2f;	/* Informational exceptions */
+			arr[3] = n - 4;
+			break;
+		case 0xd:	/* Temperature log page */
+			arr[3] = resp_temp_l_pg(arr + 4);
+			break;
+		case 0x2f:	/* Informational exceptions log page */
+			arr[3] = resp_ie_l_pg(arr + 4);
+			break;
+		default:
+			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
+			return check_condition_result;
+		}
+	} else if (0xff == subpcode) {
+		arr[0] |= 0x40;
+		arr[1] = subpcode;
+		switch (pcode) {
+		case 0x0:	/* Supported log pages and subpages log page */
+			n = 4;
+			arr[n++] = 0x0;
+			arr[n++] = 0x0;		/* 0,0 page */
+			arr[n++] = 0x0;
+			arr[n++] = 0xff;	/* this page */
+			arr[n++] = 0xd;
+			arr[n++] = 0x0;		/* Temperature */
+			arr[n++] = 0x2f;
+			arr[n++] = 0x0;	/* Informational exceptions */
+			arr[3] = n - 4;
+			break;
+		case 0xd:	/* Temperature subpages */
+			n = 4;
+			arr[n++] = 0xd;
+			arr[n++] = 0x0;		/* Temperature */
+			arr[3] = n - 4;
+			break;
+		case 0x2f:	/* Informational exceptions subpages */
+			n = 4;
+			arr[n++] = 0x2f;
+			arr[n++] = 0x0;		/* Informational exceptions */
+			arr[3] = n - 4;
+			break;
+		default:
+			mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, 5);
+			return check_condition_result;
+		}
+	} else {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 3, -1);
+		return check_condition_result;
+	}
+	len = min(get_unaligned_be16(arr + 2) + 4, alloc_len);
+	return fill_from_dev_buffer(scp, arr,
+		    min(len, SDEBUG_MAX_INQ_ARR_SZ));
+}
+
+static int check_device_access_params(struct scsi_cmnd *scp,
+				      unsigned long long lba, unsigned int num)
+{
+	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;
+	}
+	return 0;
+}
+
+/* Returns number of bytes copied or -1 if error. */
+static int do_device_access(struct scsi_cmnd *scmd, u32 sg_skip, u64 lba,
+			    u32 num, bool do_write)
+{
+	int ret;
+	u64 block, rest = 0;
+	struct scsi_data_buffer *sdb;
+	enum dma_data_direction dir;
+
+	if (do_write) {
+		sdb = scsi_out(scmd);
+		dir = DMA_TO_DEVICE;
+		write_since_sync = true;
+	} else {
+		sdb = scsi_in(scmd);
+		dir = DMA_FROM_DEVICE;
+	}
+
+	if (!sdb->length)
+		return 0;
+	if (!(scsi_bidi_cmnd(scmd) || scmd->sc_data_direction == dir))
+		return -1;
+
+	block = do_div(lba, sdebug_store_sectors);
+	if (block + num > sdebug_store_sectors)
+		rest = block + num - sdebug_store_sectors;
+
+	ret = sg_copy_buffer(sdb->table.sgl, sdb->table.nents,
+		   fake_storep + (block * sdebug_sector_size),
+		   (num - rest) * sdebug_sector_size, sg_skip, do_write);
+	if (ret != (num - rest) * sdebug_sector_size)
+		return ret;
+
+	if (rest) {
+		ret += sg_copy_buffer(sdb->table.sgl, sdb->table.nents,
+			    fake_storep, rest * sdebug_sector_size,
+			    sg_skip + ((num - rest) * sdebug_sector_size),
+			    do_write);
+	}
+
+	return ret;
+}
+
+/* If lba2fake_store(lba,num) compares equal to arr(num), then copy top half of
+ * arr into lba2fake_store(lba,num) and return true. If comparison fails then
+ * return false. */
+static bool comp_write_worker(u64 lba, u32 num, const u8 *arr)
+{
+	bool res;
+	u64 block, rest = 0;
+	u32 store_blks = sdebug_store_sectors;
+	u32 lb_size = sdebug_sector_size;
+
+	block = do_div(lba, store_blks);
+	if (block + num > store_blks)
+		rest = block + num - store_blks;
+
+	res = !memcmp(fake_storep + (block * lb_size), arr,
+		      (num - rest) * lb_size);
+	if (!res)
+		return res;
+	if (rest)
+		res = memcmp(fake_storep, arr + ((num - rest) * lb_size),
+			     rest * lb_size);
+	if (!res)
+		return res;
+	arr += num * lb_size;
+	memcpy(fake_storep + (block * lb_size), arr, (num - rest) * lb_size);
+	if (rest)
+		memcpy(fake_storep, arr + ((num - rest) * lb_size),
+		       rest * lb_size);
+	return res;
+}
+
+static __be16 dif_compute_csum(const void *buf, int len)
+{
+	__be16 csum;
+
+	if (sdebug_guard)
+		csum = (__force __be16)ip_compute_csum(buf, len);
+	else
+		csum = cpu_to_be16(crc_t10dif(buf, len));
+
+	return csum;
+}
+
+static int dif_verify(struct t10_pi_tuple *sdt, const void *data,
+		      sector_t sector, u32 ei_lba)
+{
+	__be16 csum = dif_compute_csum(data, sdebug_sector_size);
+
+	if (sdt->guard_tag != csum) {
+		pr_err("GUARD check failed on sector %lu rcvd 0x%04x, data 0x%04x\n",
+			(unsigned long)sector,
+			be16_to_cpu(sdt->guard_tag),
+			be16_to_cpu(csum));
+		return 0x01;
+	}
+	if (sdebug_dif == T10_PI_TYPE1_PROTECTION &&
+	    be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
+		pr_err("REF check failed on sector %lu\n",
+			(unsigned long)sector);
+		return 0x03;
+	}
+	if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
+	    be32_to_cpu(sdt->ref_tag) != ei_lba) {
+		pr_err("REF check failed on sector %lu\n",
+			(unsigned long)sector);
+		return 0x03;
+	}
+	return 0;
+}
+
+static void dif_copy_prot(struct scsi_cmnd *SCpnt, sector_t sector,
+			  unsigned int sectors, bool read)
+{
+	size_t resid;
+	void *paddr;
+	const void *dif_store_end = dif_storep + sdebug_store_sectors;
+	struct sg_mapping_iter miter;
+
+	/* Bytes of protection data to copy into sgl */
+	resid = sectors * sizeof(*dif_storep);
+
+	sg_miter_start(&miter, scsi_prot_sglist(SCpnt),
+			scsi_prot_sg_count(SCpnt), SG_MITER_ATOMIC |
+			(read ? SG_MITER_TO_SG : SG_MITER_FROM_SG));
+
+	while (sg_miter_next(&miter) && resid > 0) {
+		size_t len = min(miter.length, resid);
+		void *start = dif_store(sector);
+		size_t rest = 0;
+
+		if (dif_store_end < start + len)
+			rest = start + len - dif_store_end;
+
+		paddr = miter.addr;
+
+		if (read)
+			memcpy(paddr, start, len - rest);
+		else
+			memcpy(start, paddr, len - rest);
+
+		if (rest) {
+			if (read)
+				memcpy(paddr + len - rest, dif_storep, rest);
+			else
+				memcpy(dif_storep, paddr + len - rest, rest);
+		}
+
+		sector += len / sizeof(*dif_storep);
+		resid -= len;
+	}
+	sg_miter_stop(&miter);
+}
+
+static int prot_verify_read(struct scsi_cmnd *SCpnt, sector_t start_sec,
+			    unsigned int sectors, u32 ei_lba)
+{
+	unsigned int i;
+	struct t10_pi_tuple *sdt;
+	sector_t sector;
+
+	for (i = 0; i < sectors; i++, ei_lba++) {
+		int ret;
+
+		sector = start_sec + i;
+		sdt = dif_store(sector);
+
+		if (sdt->app_tag == cpu_to_be16(0xffff))
+			continue;
+
+		ret = dif_verify(sdt, lba2fake_store(sector), sector, ei_lba);
+		if (ret) {
+			dif_errors++;
+			return ret;
+		}
+	}
+
+	dif_copy_prot(SCpnt, start_sec, sectors, true);
+	dix_reads++;
+
+	return 0;
+}
+
+static int resp_read_dt0(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	struct sdebug_queued_cmd *sqcp;
+	u64 lba;
+	u32 num;
+	u32 ei_lba;
+	unsigned long iflags;
+	int ret;
+	bool check_prot;
+
+	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 (unlikely(have_dif_prot && check_prot)) {
+		if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
+		    (cmd[1] & 0xe0)) {
+			mk_sense_invalid_opcode(scp);
+			return check_condition_result;
+		}
+		if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
+		     sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
+		    (cmd[1] & 0xe0) == 0)
+			sdev_printk(KERN_ERR, scp->device, "Unprotected RD "
+				    "to DIF device\n");
+	}
+	if (unlikely(sdebug_any_injecting_opt)) {
+		sqcp = (struct sdebug_queued_cmd *)scp->host_scribble;
+
+		if (sqcp) {
+			if (sqcp->inj_short)
+				num /= 2;
+		}
+	} 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;
+	}
+
+	if (unlikely((SDEBUG_OPT_MEDIUM_ERR & sdebug_opts) &&
+		     (lba <= (sdebug_medium_error_start + sdebug_medium_error_count - 1)) &&
+		     ((lba + num) > sdebug_medium_error_start))) {
+		/* claim unrecoverable read error */
+		mk_sense_buffer(scp, MEDIUM_ERROR, UNRECOVERED_READ_ERR, 0);
+		/* set info field and valid bit for fixed descriptor */
+		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;
+			put_unaligned_be32(ret, scp->sense_buffer + 3);
+		}
+		scsi_set_resid(scp, scsi_bufflen(scp));
+		return check_condition_result;
+	}
+
+	read_lock_irqsave(&atomic_rw, iflags);
+
+	/* DIX + T10 DIF */
+	if (unlikely(sdebug_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(scp, ABORTED_COMMAND, 0x10, prot_ret);
+			return illegal_condition_result;
+		}
+	}
+
+	ret = do_device_access(scp, 0, lba, num, false);
+	read_unlock_irqrestore(&atomic_rw, iflags);
+	if (unlikely(ret == -1))
+		return DID_ERROR << 16;
+
+	scsi_in(scp)->resid = scsi_bufflen(scp) - ret;
+
+	if (unlikely(sqcp)) {
+		if (sqcp->inj_recovered) {
+			mk_sense_buffer(scp, RECOVERED_ERROR,
+					THRESHOLD_EXCEEDED, 0);
+			return check_condition_result;
+		} else if (sqcp->inj_transport) {
+			mk_sense_buffer(scp, ABORTED_COMMAND,
+					TRANSPORT_PROBLEM, ACK_NAK_TO);
+			return check_condition_result;
+		} else if (sqcp->inj_dif) {
+			/* Logical block guard check failed */
+			mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
+			return illegal_condition_result;
+		} else if (sqcp->inj_dix) {
+			mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
+			return illegal_condition_result;
+		}
+	}
+	return 0;
+}
+
+static void dump_sector(unsigned char *buf, int len)
+{
+	int i, j, n;
+
+	pr_err(">>> Sector Dump <<<\n");
+	for (i = 0 ; i < len ; i += 16) {
+		char b[128];
+
+		for (j = 0, n = 0; j < 16; j++) {
+			unsigned char c = buf[i+j];
+
+			if (c >= 0x20 && c < 0x7e)
+				n += scnprintf(b + n, sizeof(b) - n,
+					       " %c ", buf[i+j]);
+			else
+				n += scnprintf(b + n, sizeof(b) - n,
+					       "%02x ", buf[i+j]);
+		}
+		pr_err("%04d: %s\n", i, b);
+	}
+}
+
+static int prot_verify_write(struct scsi_cmnd *SCpnt, sector_t start_sec,
+			     unsigned int sectors, u32 ei_lba)
+{
+	int ret;
+	struct t10_pi_tuple *sdt;
+	void *daddr;
+	sector_t sector = start_sec;
+	int ppage_offset;
+	int dpage_offset;
+	struct sg_mapping_iter diter;
+	struct sg_mapping_iter piter;
+
+	BUG_ON(scsi_sg_count(SCpnt) == 0);
+	BUG_ON(scsi_prot_sg_count(SCpnt) == 0);
+
+	sg_miter_start(&piter, scsi_prot_sglist(SCpnt),
+			scsi_prot_sg_count(SCpnt),
+			SG_MITER_ATOMIC | SG_MITER_FROM_SG);
+	sg_miter_start(&diter, scsi_sglist(SCpnt), scsi_sg_count(SCpnt),
+			SG_MITER_ATOMIC | SG_MITER_FROM_SG);
+
+	/* For each protection page */
+	while (sg_miter_next(&piter)) {
+		dpage_offset = 0;
+		if (WARN_ON(!sg_miter_next(&diter))) {
+			ret = 0x01;
+			goto out;
+		}
+
+		for (ppage_offset = 0; ppage_offset < piter.length;
+		     ppage_offset += sizeof(struct t10_pi_tuple)) {
+			/* If we're at the end of the current
+			 * data page advance to the next one
+			 */
+			if (dpage_offset >= diter.length) {
+				if (WARN_ON(!sg_miter_next(&diter))) {
+					ret = 0x01;
+					goto out;
+				}
+				dpage_offset = 0;
+			}
+
+			sdt = piter.addr + ppage_offset;
+			daddr = diter.addr + dpage_offset;
+
+			ret = dif_verify(sdt, daddr, sector, ei_lba);
+			if (ret) {
+				dump_sector(daddr, sdebug_sector_size);
+				goto out;
+			}
+
+			sector++;
+			ei_lba++;
+			dpage_offset += sdebug_sector_size;
+		}
+		diter.consumed = dpage_offset;
+		sg_miter_stop(&diter);
+	}
+	sg_miter_stop(&piter);
+
+	dif_copy_prot(SCpnt, start_sec, sectors, false);
+	dix_writes++;
+
+	return 0;
+
+out:
+	dif_errors++;
+	sg_miter_stop(&diter);
+	sg_miter_stop(&piter);
+	return ret;
+}
+
+static unsigned long lba_to_map_index(sector_t lba)
+{
+	if (sdebug_unmap_alignment)
+		lba += sdebug_unmap_granularity - sdebug_unmap_alignment;
+	sector_div(lba, sdebug_unmap_granularity);
+	return lba;
+}
+
+static sector_t map_index_to_lba(unsigned long index)
+{
+	sector_t lba = index * sdebug_unmap_granularity;
+
+	if (sdebug_unmap_alignment)
+		lba -= sdebug_unmap_granularity - sdebug_unmap_alignment;
+	return lba;
+}
+
+static unsigned int map_state(sector_t lba, unsigned int *num)
+{
+	sector_t end;
+	unsigned int mapped;
+	unsigned long index;
+	unsigned long next;
+
+	index = lba_to_map_index(lba);
+	mapped = test_bit(index, map_storep);
+
+	if (mapped)
+		next = find_next_zero_bit(map_storep, map_size, index);
+	else
+		next = find_next_bit(map_storep, map_size, index);
+
+	end = min_t(sector_t, sdebug_store_sectors,  map_index_to_lba(next));
+	*num = end - lba;
+	return mapped;
+}
+
+static void map_region(sector_t lba, unsigned int len)
+{
+	sector_t end = lba + len;
+
+	while (lba < end) {
+		unsigned long index = lba_to_map_index(lba);
+
+		if (index < map_size)
+			set_bit(index, map_storep);
+
+		lba = map_index_to_lba(index + 1);
+	}
+}
+
+static void unmap_region(sector_t lba, unsigned int len)
+{
+	sector_t end = lba + len;
+
+	while (lba < end) {
+		unsigned long index = lba_to_map_index(lba);
+
+		if (lba == map_index_to_lba(index) &&
+		    lba + sdebug_unmap_granularity <= end &&
+		    index < map_size) {
+			clear_bit(index, map_storep);
+			if (sdebug_lbprz) {  /* for LBPRZ=2 return 0xff_s */
+				memset(fake_storep +
+				       lba * sdebug_sector_size,
+				       (sdebug_lbprz & 1) ? 0 : 0xff,
+				       sdebug_sector_size *
+				       sdebug_unmap_granularity);
+			}
+			if (dif_storep) {
+				memset(dif_storep + lba, 0xff,
+				       sizeof(*dif_storep) *
+				       sdebug_unmap_granularity);
+			}
+		}
+		lba = map_index_to_lba(index + 1);
+	}
+}
+
+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;
+
+	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 (unlikely(have_dif_prot && check_prot)) {
+		if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
+		    (cmd[1] & 0xe0)) {
+			mk_sense_invalid_opcode(scp);
+			return check_condition_result;
+		}
+		if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
+		     sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
+		    (cmd[1] & 0xe0) == 0)
+			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;
+	}
+
+	write_lock_irqsave(&atomic_rw, iflags);
+
+	/* DIX + T10 DIF */
+	if (unlikely(sdebug_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(scp, ILLEGAL_REQUEST, 0x10, prot_ret);
+			return illegal_condition_result;
+		}
+	}
+
+	ret = do_device_access(scp, 0, lba, num, true);
+	if (unlikely(scsi_debug_lbp()))
+		map_region(lba, num);
+	write_unlock_irqrestore(&atomic_rw, iflags);
+	if (unlikely(-1 == ret))
+		return DID_ERROR << 16;
+	else if (unlikely(sdebug_verbose &&
+			  (ret < (num * sdebug_sector_size))))
+		sdev_printk(KERN_INFO, scp->device,
+			    "%s: write: cdb indicated=%u, IO sent=%d bytes\n",
+			    my_name, num * sdebug_sector_size, ret);
+
+	if (unlikely(sdebug_any_injecting_opt)) {
+		struct sdebug_queued_cmd *sqcp =
+				(struct sdebug_queued_cmd *)scp->host_scribble;
+
+		if (sqcp) {
+			if (sqcp->inj_recovered) {
+				mk_sense_buffer(scp, RECOVERED_ERROR,
+						THRESHOLD_EXCEEDED, 0);
+				return check_condition_result;
+			} else if (sqcp->inj_dif) {
+				/* Logical block guard check failed */
+				mk_sense_buffer(scp, ABORTED_COMMAND, 0x10, 1);
+				return illegal_condition_result;
+			} else if (sqcp->inj_dix) {
+				mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10, 1);
+				return illegal_condition_result;
+			}
+		}
+	}
+	return 0;
+}
+
+/*
+ * T10 has only specified WRITE SCATTERED(16) and WRITE SCATTERED(32).
+ * No READ GATHERED yet (requires bidi or long cdb holding gather list).
+ */
+static int resp_write_scat(struct scsi_cmnd *scp,
+			   struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	u8 *lrdp = NULL;
+	u8 *up;
+	u8 wrprotect;
+	u16 lbdof, num_lrd, k;
+	u32 num, num_by, bt_len, lbdof_blen, sg_off, cum_lb;
+	u32 lb_size = sdebug_sector_size;
+	u32 ei_lba;
+	u64 lba;
+	unsigned long iflags;
+	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;
+		wrprotect = (cmd[10] >> 5) & 0x7;
+		lbdof = get_unaligned_be16(cmd + 12);
+		num_lrd = get_unaligned_be16(cmd + 16);
+		bt_len = get_unaligned_be32(cmd + 28);
+	} else {        /* that leaves WRITE SCATTERED(16) */
+		is_16 = true;
+		wrprotect = (cmd[2] >> 5) & 0x7;
+		lbdof = get_unaligned_be16(cmd + 4);
+		num_lrd = get_unaligned_be16(cmd + 8);
+		bt_len = get_unaligned_be32(cmd + 10);
+		if (unlikely(have_dif_prot)) {
+			if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
+			    wrprotect) {
+				mk_sense_invalid_opcode(scp);
+				return illegal_condition_result;
+			}
+			if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
+			     sdebug_dif == T10_PI_TYPE3_PROTECTION) &&
+			     wrprotect == 0)
+				sdev_printk(KERN_ERR, scp->device,
+					    "Unprotected WR to DIF device\n");
+		}
+	}
+	if ((num_lrd == 0) || (bt_len == 0))
+		return 0;       /* T10 says these do-nothings are not errors */
+	if (lbdof == 0) {
+		if (sdebug_verbose)
+			sdev_printk(KERN_INFO, scp->device,
+				"%s: %s: LB Data Offset field bad\n",
+				my_name, __func__);
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
+		return illegal_condition_result;
+	}
+	lbdof_blen = lbdof * lb_size;
+	if ((lrd_size + (num_lrd * lrd_size)) > lbdof_blen) {
+		if (sdebug_verbose)
+			sdev_printk(KERN_INFO, scp->device,
+				"%s: %s: LBA range descriptors don't fit\n",
+				my_name, __func__);
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
+		return illegal_condition_result;
+	}
+	lrdp = kzalloc(lbdof_blen, GFP_ATOMIC);
+	if (lrdp == NULL)
+		return SCSI_MLQUEUE_HOST_BUSY;
+	if (sdebug_verbose)
+		sdev_printk(KERN_INFO, scp->device,
+			"%s: %s: Fetch header+scatter_list, lbdof_blen=%u\n",
+			my_name, __func__, lbdof_blen);
+	res = fetch_to_dev_buffer(scp, lrdp, lbdof_blen);
+	if (res == -1) {
+		ret = DID_ERROR << 16;
+		goto err_out;
+	}
+
+	write_lock_irqsave(&atomic_rw, iflags);
+	sg_off = lbdof_blen;
+	/* Spec says Buffer xfer Length field in number of LBs in dout */
+	cum_lb = 0;
+	for (k = 0, up = lrdp + lrd_size; k < num_lrd; ++k, up += lrd_size) {
+		lba = get_unaligned_be64(up + 0);
+		num = get_unaligned_be32(up + 8);
+		if (sdebug_verbose)
+			sdev_printk(KERN_INFO, scp->device,
+				"%s: %s: k=%d  LBA=0x%llx num=%u  sg_off=%u\n",
+				my_name, __func__, k, lba, num, sg_off);
+		if (num == 0)
+			continue;
+		ret = check_device_access_params(scp, lba, num);
+		if (ret)
+			goto err_out_unlock;
+		num_by = num * lb_size;
+		ei_lba = is_16 ? 0 : get_unaligned_be32(up + 12);
+
+		if ((cum_lb + num) > bt_len) {
+			if (sdebug_verbose)
+				sdev_printk(KERN_INFO, scp->device,
+				    "%s: %s: sum of blocks > data provided\n",
+				    my_name, __func__);
+			mk_sense_buffer(scp, ILLEGAL_REQUEST, WRITE_ERROR_ASC,
+					0);
+			ret = illegal_condition_result;
+			goto err_out_unlock;
+		}
+
+		/* DIX + T10 DIF */
+		if (unlikely(sdebug_dix && scsi_prot_sg_count(scp))) {
+			int prot_ret = prot_verify_write(scp, lba, num,
+							 ei_lba);
+
+			if (prot_ret) {
+				mk_sense_buffer(scp, ILLEGAL_REQUEST, 0x10,
+						prot_ret);
+				ret = illegal_condition_result;
+				goto err_out_unlock;
+			}
+		}
+
+		ret = do_device_access(scp, sg_off, lba, num, true);
+		if (unlikely(scsi_debug_lbp()))
+			map_region(lba, num);
+		if (unlikely(-1 == ret)) {
+			ret = DID_ERROR << 16;
+			goto err_out_unlock;
+		} else if (unlikely(sdebug_verbose && (ret < num_by)))
+			sdev_printk(KERN_INFO, scp->device,
+			    "%s: write: cdb indicated=%u, IO sent=%d bytes\n",
+			    my_name, num_by, ret);
+
+		if (unlikely(sdebug_any_injecting_opt)) {
+			struct sdebug_queued_cmd *sqcp =
+				(struct sdebug_queued_cmd *)scp->host_scribble;
+
+			if (sqcp) {
+				if (sqcp->inj_recovered) {
+					mk_sense_buffer(scp, RECOVERED_ERROR,
+							THRESHOLD_EXCEEDED, 0);
+					ret = illegal_condition_result;
+					goto err_out_unlock;
+				} else if (sqcp->inj_dif) {
+					/* Logical block guard check failed */
+					mk_sense_buffer(scp, ABORTED_COMMAND,
+							0x10, 1);
+					ret = illegal_condition_result;
+					goto err_out_unlock;
+				} else if (sqcp->inj_dix) {
+					mk_sense_buffer(scp, ILLEGAL_REQUEST,
+							0x10, 1);
+					ret = illegal_condition_result;
+					goto err_out_unlock;
+				}
+			}
+		}
+		sg_off += num_by;
+		cum_lb += num;
+	}
+	ret = 0;
+err_out_unlock:
+	write_unlock_irqrestore(&atomic_rw, iflags);
+err_out:
+	kfree(lrdp);
+	return ret;
+}
+
+static int resp_write_same(struct scsi_cmnd *scp, u64 lba, u32 num,
+			   u32 ei_lba, bool unmap, bool ndob)
+{
+	int ret;
+	unsigned long iflags;
+	unsigned long long i;
+	u32 lb_size = sdebug_sector_size;
+	u64 block, lbaa;
+	u8 *fs1p;
+
+	ret = check_device_access_params(scp, lba, num);
+	if (ret)
+		return ret;
+
+	write_lock_irqsave(&atomic_rw, iflags);
+
+	if (unmap && scsi_debug_lbp()) {
+		unmap_region(lba, num);
+		goto out;
+	}
+	lbaa = lba;
+	block = do_div(lbaa, sdebug_store_sectors);
+	/* if ndob then zero 1 logical block, else fetch 1 logical block */
+	fs1p = fake_storep + (block * lb_size);
+	if (ndob) {
+		memset(fs1p, 0, lb_size);
+		ret = 0;
+	} else
+		ret = fetch_to_dev_buffer(scp, fs1p, lb_size);
+
+	if (-1 == ret) {
+		write_unlock_irqrestore(&atomic_rw, iflags);
+		return DID_ERROR << 16;
+	} else if (sdebug_verbose && !ndob && (ret < lb_size))
+		sdev_printk(KERN_INFO, scp->device,
+			    "%s: %s: lb size=%u, IO sent=%d bytes\n",
+			    my_name, "write same", lb_size, ret);
+
+	/* Copy first sector to remaining blocks */
+	for (i = 1 ; i < num ; i++) {
+		lbaa = lba + i;
+		block = do_div(lbaa, sdebug_store_sectors);
+		memmove(fake_storep + (block * lb_size), fs1p, lb_size);
+	}
+	if (scsi_debug_lbp())
+		map_region(lba, num);
+out:
+	write_unlock_irqrestore(&atomic_rw, iflags);
+
+	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 (sdebug_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 > sdebug_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 (sdebug_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 > sdebug_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);
+}
+
+/* Note the mode field is in the same position as the (lower) service action
+ * field. For the Report supported operation codes command, SPC-4 suggests
+ * each mode of this command should be reported separately; for future. */
+static int resp_write_buffer(struct scsi_cmnd *scp,
+			     struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	struct scsi_device *sdp = scp->device;
+	struct sdebug_dev_info *dp;
+	u8 mode;
+
+	mode = cmd[1] & 0x1f;
+	switch (mode) {
+	case 0x4:	/* download microcode (MC) and activate (ACT) */
+		/* set UAs on this device only */
+		set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
+		set_bit(SDEBUG_UA_MICROCODE_CHANGED, devip->uas_bm);
+		break;
+	case 0x5:	/* download MC, save and ACT */
+		set_bit(SDEBUG_UA_MICROCODE_CHANGED_WO_RESET, devip->uas_bm);
+		break;
+	case 0x6:	/* download MC with offsets and ACT */
+		/* set UAs on most devices (LUs) in this target */
+		list_for_each_entry(dp,
+				    &devip->sdbg_host->dev_info_list,
+				    dev_list)
+			if (dp->target == sdp->id) {
+				set_bit(SDEBUG_UA_BUS_RESET, dp->uas_bm);
+				if (devip != dp)
+					set_bit(SDEBUG_UA_MICROCODE_CHANGED,
+						dp->uas_bm);
+			}
+		break;
+	case 0x7:	/* download MC with offsets, save, and ACT */
+		/* set UA on all devices (LUs) in this target */
+		list_for_each_entry(dp,
+				    &devip->sdbg_host->dev_info_list,
+				    dev_list)
+			if (dp->target == sdp->id)
+				set_bit(SDEBUG_UA_MICROCODE_CHANGED_WO_RESET,
+					dp->uas_bm);
+		break;
+	default:
+		/* do nothing for this command for other mode values */
+		break;
+	}
+	return 0;
+}
+
+static int resp_comp_write(struct scsi_cmnd *scp,
+			   struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	u8 *arr;
+	u8 *fake_storep_hold;
+	u64 lba;
+	u32 dnum;
+	u32 lb_size = sdebug_sector_size;
+	u8 num;
+	unsigned long iflags;
+	int ret;
+	int retval = 0;
+
+	lba = get_unaligned_be64(cmd + 2);
+	num = cmd[13];		/* 1 to a maximum of 255 logical blocks */
+	if (0 == num)
+		return 0;	/* degenerate case, not an error */
+	if (sdebug_dif == T10_PI_TYPE2_PROTECTION &&
+	    (cmd[1] & 0xe0)) {
+		mk_sense_invalid_opcode(scp);
+		return check_condition_result;
+	}
+	if ((sdebug_dif == T10_PI_TYPE1_PROTECTION ||
+	     sdebug_dif == T10_PI_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;
+	}
+	dnum = 2 * num;
+	arr = kcalloc(lb_size, dnum, GFP_ATOMIC);
+	if (NULL == arr) {
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, INSUFF_RES_ASC,
+				INSUFF_RES_ASCQ);
+		return check_condition_result;
+	}
+
+	write_lock_irqsave(&atomic_rw, iflags);
+
+	/* trick do_device_access() to fetch both compare and write buffers
+	 * from data-in into arr. Safe (atomic) since write_lock held. */
+	fake_storep_hold = fake_storep;
+	fake_storep = arr;
+	ret = do_device_access(scp, 0, 0, dnum, true);
+	fake_storep = fake_storep_hold;
+	if (ret == -1) {
+		retval = DID_ERROR << 16;
+		goto cleanup;
+	} else if (sdebug_verbose && (ret < (dnum * lb_size)))
+		sdev_printk(KERN_INFO, scp->device, "%s: compare_write: cdb "
+			    "indicated=%u, IO sent=%d bytes\n", my_name,
+			    dnum * lb_size, ret);
+	if (!comp_write_worker(lba, num, arr)) {
+		mk_sense_buffer(scp, MISCOMPARE, MISCOMPARE_VERIFY_ASC, 0);
+		retval = check_condition_result;
+		goto cleanup;
+	}
+	if (scsi_debug_lbp())
+		map_region(lba, num);
+cleanup:
+	write_unlock_irqrestore(&atomic_rw, iflags);
+	kfree(arr);
+	return retval;
+}
+
+struct unmap_block_desc {
+	__be64	lba;
+	__be32	blocks;
+	__be32	__reserved;
+};
+
+static int resp_unmap(struct scsi_cmnd *scp, struct sdebug_dev_info *devip)
+{
+	unsigned char *buf;
+	struct unmap_block_desc *desc;
+	unsigned int i, payload_len, descriptors;
+	int ret;
+	unsigned long iflags;
+
+
+	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;
+	if (descriptors > sdebug_unmap_max_desc) {
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 7, -1);
+		return check_condition_result;
+	}
+
+	buf = kzalloc(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);
+
+	desc = (void *)&buf[8];
+
+	write_lock_irqsave(&atomic_rw, iflags);
+
+	for (i = 0 ; i < descriptors ; i++) {
+		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);
+		if (ret)
+			goto out;
+
+		unmap_region(lba, num);
+	}
+
+	ret = 0;
+
+out:
+	write_unlock_irqrestore(&atomic_rw, iflags);
+	kfree(buf);
+
+	return ret;
+}
+
+#define SDEBUG_GET_LBA_STATUS_LEN 32
+
+static int resp_get_lba_status(struct scsi_cmnd *scp,
+			       struct sdebug_dev_info *devip)
+{
+	u8 *cmd = scp->cmnd;
+	u64 lba;
+	u32 alloc_len, mapped, num;
+	u8 arr[SDEBUG_GET_LBA_STATUS_LEN];
+	int ret;
+
+	lba = get_unaligned_be64(cmd + 2);
+	alloc_len = get_unaligned_be32(cmd + 10);
+
+	if (alloc_len < 24)
+		return 0;
+
+	ret = check_device_access_params(scp, lba, 1);
+	if (ret)
+		return ret;
+
+	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);		/* 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(scp, arr, SDEBUG_GET_LBA_STATUS_LEN);
+}
+
+static int resp_sync_cache(struct scsi_cmnd *scp,
+			   struct sdebug_dev_info *devip)
+{
+	int res = 0;
+	u64 lba;
+	u32 num_blocks;
+	u8 *cmd = scp->cmnd;
+
+	if (cmd[0] == SYNCHRONIZE_CACHE) {	/* 10 byte cdb */
+		lba = get_unaligned_be32(cmd + 2);
+		num_blocks = get_unaligned_be16(cmd + 7);
+	} else {				/* SYNCHRONIZE_CACHE(16) */
+		lba = get_unaligned_be64(cmd + 2);
+		num_blocks = get_unaligned_be32(cmd + 10);
+	}
+	if (lba + num_blocks > sdebug_capacity) {
+		mk_sense_buffer(scp, ILLEGAL_REQUEST, LBA_OUT_OF_RANGE, 0);
+		return check_condition_result;
+	}
+	if (!write_since_sync || cmd[1] & 0x2)
+		res = SDEG_RES_IMMED_MASK;
+	else		/* delay if write_since_sync and IMMED clear */
+		write_since_sync = false;
+	return res;
+}
+
+#define RL_BUCKET_ELEMS 8
+
+/* Even though each pseudo target has a REPORT LUNS "well known logical unit"
+ * (W-LUN), the normal Linux scanning logic does not associate it with a
+ * device (e.g. /dev/sg7). The following magic will make that association:
+ *   "cd /sys/class/scsi_host/host<n> ; echo '- - 49409' > scan"
+ * where <n> is a host number. If there are multiple targets in a host then
+ * the above will associate a W-LUN to each target. To only get a W-LUN
+ * for target 2, then use "echo '- 2 49409' > scan" .
+ */
+static int resp_report_luns(struct scsi_cmnd *scp,
+			    struct sdebug_dev_info *devip)
+{
+	unsigned char *cmd = scp->cmnd;
+	unsigned int alloc_len;
+	unsigned char select_report;
+	u64 lun;
+	struct scsi_lun *lun_p;
+	u8 arr[RL_BUCKET_ELEMS * sizeof(struct scsi_lun)];
+	unsigned int lun_cnt;	/* normal LUN count (max: 256) */
+	unsigned int wlun_cnt;	/* report luns W-LUN count */
+	unsigned int tlun_cnt;	/* total LUN count */
+	unsigned int rlen;	/* response length (in bytes) */
+	int k, j, n, res;
+	unsigned int off_rsp = 0;
+	const int sz_lun = sizeof(struct scsi_lun);
+
+	clear_luns_changed_on_target(devip);
+
+	select_report = cmd[2];
+	alloc_len = get_unaligned_be32(cmd + 6);
+
+	if (alloc_len < 4) {
+		pr_err("alloc len too small %d\n", alloc_len);
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 6, -1);
+		return check_condition_result;
+	}
+
+	switch (select_report) {
+	case 0:		/* all LUNs apart from W-LUNs */
+		lun_cnt = sdebug_max_luns;
+		wlun_cnt = 0;
+		break;
+	case 1:		/* only W-LUNs */
+		lun_cnt = 0;
+		wlun_cnt = 1;
+		break;
+	case 2:		/* all LUNs */
+		lun_cnt = sdebug_max_luns;
+		wlun_cnt = 1;
+		break;
+	case 0x10:	/* only administrative LUs */
+	case 0x11:	/* see SPC-5 */
+	case 0x12:	/* only subsiduary LUs owned by referenced LU */
+	default:
+		pr_debug("select report invalid %d\n", select_report);
+		mk_sense_invalid_fld(scp, SDEB_IN_CDB, 2, -1);
+		return check_condition_result;
+	}
+
+	if (sdebug_no_lun_0 && (lun_cnt > 0))
+		--lun_cnt;
+
+	tlun_cnt = lun_cnt + wlun_cnt;
+	rlen = tlun_cnt * sz_lun;	/* excluding 8 byte header */
+	scsi_set_resid(scp, scsi_bufflen(scp));
+	pr_debug("select_report %d luns = %d wluns = %d no_lun0 %d\n",
+		 select_report, lun_cnt, wlun_cnt, sdebug_no_lun_0);
+
+	/* loops rely on sizeof response header same as sizeof lun (both 8) */
+	lun = sdebug_no_lun_0 ? 1 : 0;
+	for (k = 0, j = 0, res = 0; true; ++k, j = 0) {
+		memset(arr, 0, sizeof(arr));
+		lun_p = (struct scsi_lun *)&arr[0];
+		if (k == 0) {
+			put_unaligned_be32(rlen, &arr[0]);
+			++lun_p;
+			j = 1;
+		}
+		for ( ; j < RL_BUCKET_ELEMS; ++j, ++lun_p) {
+			if ((k * RL_BUCKET_ELEMS) + j > lun_cnt)
+				break;
+			int_to_scsilun(lun++, lun_p);
+		}
+		if (j < RL_BUCKET_ELEMS)
+			break;
+		n = j * sz_lun;
+		res = p_fill_from_dev_buffer(scp, arr, n, off_rsp);
+		if (res)
+			return res;
+		off_rsp += n;
+	}
+	if (wlun_cnt) {
+		int_to_scsilun(SCSI_W_LUN_REPORT_LUNS, lun_p);
+		++j;
+	}
+	if (j > 0)
+		res = p_fill_from_dev_buffer(scp, arr, j * sz_lun, off_rsp);
+	return res;
+}
+
+static int resp_xdwriteread(struct scsi_cmnd *scp, unsigned long long lba,
+			    unsigned int num, struct sdebug_dev_info *devip)
+{
+	int j;
+	unsigned char *kaddr, *buf;
+	unsigned int offset;
+	struct scsi_data_buffer *sdb = scsi_in(scp);
+	struct sg_mapping_iter miter;
+
+	/* better not to use temporary buffer. */
+	buf = kzalloc(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));
+
+	offset = 0;
+	sg_miter_start(&miter, sdb->table.sgl, sdb->table.nents,
+			SG_MITER_ATOMIC | SG_MITER_TO_SG);
+
+	while (sg_miter_next(&miter)) {
+		kaddr = miter.addr;
+		for (j = 0; j < miter.length; j++)
+			*(kaddr + j) ^= *(buf + offset + j);
+
+		offset += miter.length;
+	}
+	sg_miter_stop(&miter);
+	kfree(buf);
+
+	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);
+}
+
+static struct sdebug_queue *get_queue(struct scsi_cmnd *cmnd)
+{
+	u32 tag = blk_mq_unique_tag(cmnd->request);
+	u16 hwq = blk_mq_unique_tag_to_hwq(tag);
+
+	pr_debug("tag=%#x, hwq=%d\n", tag, hwq);
+	if (WARN_ON_ONCE(hwq >= submit_queues))
+		hwq = 0;
+	return sdebug_q_arr + hwq;
+}
+
+/* Queued (deferred) command completions converge here. */
+static void sdebug_q_cmd_complete(struct sdebug_defer *sd_dp)
+{
+	bool aborted = sd_dp->aborted;
+	int qc_idx;
+	int retiring = 0;
+	unsigned long iflags;
+	struct sdebug_queue *sqp;
+	struct sdebug_queued_cmd *sqcp;
+	struct scsi_cmnd *scp;
+	struct sdebug_dev_info *devip;
+
+	sd_dp->defer_t = SDEB_DEFER_NONE;
+	if (unlikely(aborted))
+		sd_dp->aborted = false;
+	qc_idx = sd_dp->qc_idx;
+	sqp = sdebug_q_arr + sd_dp->sqa_idx;
+	if (sdebug_statistics) {
+		atomic_inc(&sdebug_completions);
+		if (raw_smp_processor_id() != sd_dp->issuing_cpu)
+			atomic_inc(&sdebug_miss_cpus);
+	}
+	if (unlikely((qc_idx < 0) || (qc_idx >= SDEBUG_CANQUEUE))) {
+		pr_err("wild qc_idx=%d\n", qc_idx);
+		return;
+	}
+	spin_lock_irqsave(&sqp->qc_lock, iflags);
+	sqcp = &sqp->qc_arr[qc_idx];
+	scp = sqcp->a_cmnd;
+	if (unlikely(scp == NULL)) {
+		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+		pr_err("scp is NULL, sqa_idx=%d, qc_idx=%d\n",
+		       sd_dp->sqa_idx, qc_idx);
+		return;
+	}
+	devip = (struct sdebug_dev_info *)scp->device->hostdata;
+	if (likely(devip))
+		atomic_dec(&devip->num_in_q);
+	else
+		pr_err("devip=NULL\n");
+	if (unlikely(atomic_read(&retired_max_queue) > 0))
+		retiring = 1;
+
+	sqcp->a_cmnd = NULL;
+	if (unlikely(!test_and_clear_bit(qc_idx, sqp->in_use_bm))) {
+		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+		pr_err("Unexpected completion\n");
+		return;
+	}
+
+	if (unlikely(retiring)) {	/* user has reduced max_queue */
+		int k, retval;
+
+		retval = atomic_read(&retired_max_queue);
+		if (qc_idx >= retval) {
+			spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+			pr_err("index %d too large\n", retval);
+			return;
+		}
+		k = find_last_bit(sqp->in_use_bm, retval);
+		if ((k < sdebug_max_queue) || (k == retval))
+			atomic_set(&retired_max_queue, 0);
+		else
+			atomic_set(&retired_max_queue, k + 1);
+	}
+	spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+	if (unlikely(aborted)) {
+		if (sdebug_verbose)
+			pr_info("bypassing scsi_done() due to aborted cmd\n");
+		return;
+	}
+	scp->scsi_done(scp); /* callback to mid level */
+}
+
+/* When high resolution timer goes off this function is called. */
+static enum hrtimer_restart sdebug_q_cmd_hrt_complete(struct hrtimer *timer)
+{
+	struct sdebug_defer *sd_dp = container_of(timer, struct sdebug_defer,
+						  hrt);
+	sdebug_q_cmd_complete(sd_dp);
+	return HRTIMER_NORESTART;
+}
+
+/* When work queue schedules work, it calls this function. */
+static void sdebug_q_cmd_wq_complete(struct work_struct *work)
+{
+	struct sdebug_defer *sd_dp = container_of(work, struct sdebug_defer,
+						  ew.work);
+	sdebug_q_cmd_complete(sd_dp);
+}
+
+static bool got_shared_uuid;
+static uuid_t shared_uuid;
+
+static struct sdebug_dev_info *sdebug_device_create(
+			struct sdebug_host_info *sdbg_host, gfp_t flags)
+{
+	struct sdebug_dev_info *devip;
+
+	devip = kzalloc(sizeof(*devip), flags);
+	if (devip) {
+		if (sdebug_uuid_ctl == 1)
+			uuid_gen(&devip->lu_name);
+		else if (sdebug_uuid_ctl == 2) {
+			if (got_shared_uuid)
+				devip->lu_name = shared_uuid;
+			else {
+				uuid_gen(&shared_uuid);
+				got_shared_uuid = true;
+				devip->lu_name = shared_uuid;
+			}
+		}
+		devip->sdbg_host = sdbg_host;
+		list_add_tail(&devip->dev_list, &sdbg_host->dev_info_list);
+	}
+	return devip;
+}
+
+static struct sdebug_dev_info *find_build_dev_info(struct scsi_device *sdev)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct sdebug_dev_info *open_devip = NULL;
+	struct sdebug_dev_info *devip;
+
+	sdbg_host = *(struct sdebug_host_info **)shost_priv(sdev->host);
+	if (!sdbg_host) {
+		pr_err("Host info NULL\n");
+		return NULL;
+	}
+	list_for_each_entry(devip, &sdbg_host->dev_info_list, dev_list) {
+		if ((devip->used) && (devip->channel == sdev->channel) &&
+		    (devip->target == sdev->id) &&
+		    (devip->lun == sdev->lun))
+			return devip;
+		else {
+			if ((!devip->used) && (!open_devip))
+				open_devip = devip;
+		}
+	}
+	if (!open_devip) { /* try and make a new one */
+		open_devip = sdebug_device_create(sdbg_host, GFP_ATOMIC);
+		if (!open_devip) {
+			pr_err("out of memory at line %d\n", __LINE__);
+			return NULL;
+		}
+	}
+
+	open_devip->channel = sdev->channel;
+	open_devip->target = sdev->id;
+	open_devip->lun = sdev->lun;
+	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 = true;
+	return open_devip;
+}
+
+static int scsi_debug_slave_alloc(struct scsi_device *sdp)
+{
+	if (sdebug_verbose)
+		pr_info("slave_alloc <%u %u %u %llu>\n",
+		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
+	blk_queue_flag_set(QUEUE_FLAG_BIDI, sdp->request_queue);
+	return 0;
+}
+
+static int scsi_debug_slave_configure(struct scsi_device *sdp)
+{
+	struct sdebug_dev_info *devip =
+			(struct sdebug_dev_info *)sdp->hostdata;
+
+	if (sdebug_verbose)
+		pr_info("slave_configure <%u %u %u %llu>\n",
+		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
+	if (sdp->host->max_cmd_len != SDEBUG_MAX_CMD_LEN)
+		sdp->host->max_cmd_len = SDEBUG_MAX_CMD_LEN;
+	if (devip == NULL) {
+		devip = find_build_dev_info(sdp);
+		if (devip == NULL)
+			return 1;  /* no resources, will be marked offline */
+	}
+	sdp->hostdata = devip;
+	blk_queue_max_segment_size(sdp->request_queue, -1U);
+	if (sdebug_no_uld)
+		sdp->no_uld_attach = 1;
+	config_cdb_len(sdp);
+	return 0;
+}
+
+static void scsi_debug_slave_destroy(struct scsi_device *sdp)
+{
+	struct sdebug_dev_info *devip =
+		(struct sdebug_dev_info *)sdp->hostdata;
+
+	if (sdebug_verbose)
+		pr_info("slave_destroy <%u %u %u %llu>\n",
+		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
+	if (devip) {
+		/* make this slot available for re-use */
+		devip->used = false;
+		sdp->hostdata = NULL;
+	}
+}
+
+static void stop_qc_helper(struct sdebug_defer *sd_dp,
+			   enum sdeb_defer_type defer_t)
+{
+	if (!sd_dp)
+		return;
+	if (defer_t == SDEB_DEFER_HRT)
+		hrtimer_cancel(&sd_dp->hrt);
+	else if (defer_t == SDEB_DEFER_WQ)
+		cancel_work_sync(&sd_dp->ew.work);
+}
+
+/* If @cmnd found deletes its timer or work queue and returns true; else
+   returns false */
+static bool stop_queued_cmnd(struct scsi_cmnd *cmnd)
+{
+	unsigned long iflags;
+	int j, k, qmax, r_qmax;
+	enum sdeb_defer_type l_defer_t;
+	struct sdebug_queue *sqp;
+	struct sdebug_queued_cmd *sqcp;
+	struct sdebug_dev_info *devip;
+	struct sdebug_defer *sd_dp;
+
+	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
+		spin_lock_irqsave(&sqp->qc_lock, iflags);
+		qmax = sdebug_max_queue;
+		r_qmax = atomic_read(&retired_max_queue);
+		if (r_qmax > qmax)
+			qmax = r_qmax;
+		for (k = 0; k < qmax; ++k) {
+			if (test_bit(k, sqp->in_use_bm)) {
+				sqcp = &sqp->qc_arr[k];
+				if (cmnd != sqcp->a_cmnd)
+					continue;
+				/* found */
+				devip = (struct sdebug_dev_info *)
+						cmnd->device->hostdata;
+				if (devip)
+					atomic_dec(&devip->num_in_q);
+				sqcp->a_cmnd = NULL;
+				sd_dp = sqcp->sd_dp;
+				if (sd_dp) {
+					l_defer_t = sd_dp->defer_t;
+					sd_dp->defer_t = SDEB_DEFER_NONE;
+				} else
+					l_defer_t = SDEB_DEFER_NONE;
+				spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+				stop_qc_helper(sd_dp, l_defer_t);
+				clear_bit(k, sqp->in_use_bm);
+				return true;
+			}
+		}
+		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+	}
+	return false;
+}
+
+/* Deletes (stops) timers or work queues of all queued commands */
+static void stop_all_queued(void)
+{
+	unsigned long iflags;
+	int j, k;
+	enum sdeb_defer_type l_defer_t;
+	struct sdebug_queue *sqp;
+	struct sdebug_queued_cmd *sqcp;
+	struct sdebug_dev_info *devip;
+	struct sdebug_defer *sd_dp;
+
+	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
+		spin_lock_irqsave(&sqp->qc_lock, iflags);
+		for (k = 0; k < SDEBUG_CANQUEUE; ++k) {
+			if (test_bit(k, sqp->in_use_bm)) {
+				sqcp = &sqp->qc_arr[k];
+				if (sqcp->a_cmnd == NULL)
+					continue;
+				devip = (struct sdebug_dev_info *)
+					sqcp->a_cmnd->device->hostdata;
+				if (devip)
+					atomic_dec(&devip->num_in_q);
+				sqcp->a_cmnd = NULL;
+				sd_dp = sqcp->sd_dp;
+				if (sd_dp) {
+					l_defer_t = sd_dp->defer_t;
+					sd_dp->defer_t = SDEB_DEFER_NONE;
+				} else
+					l_defer_t = SDEB_DEFER_NONE;
+				spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+				stop_qc_helper(sd_dp, l_defer_t);
+				clear_bit(k, sqp->in_use_bm);
+				spin_lock_irqsave(&sqp->qc_lock, iflags);
+			}
+		}
+		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+	}
+}
+
+/* Free queued command memory on heap */
+static void free_all_queued(void)
+{
+	int j, k;
+	struct sdebug_queue *sqp;
+	struct sdebug_queued_cmd *sqcp;
+
+	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
+		for (k = 0; k < SDEBUG_CANQUEUE; ++k) {
+			sqcp = &sqp->qc_arr[k];
+			kfree(sqcp->sd_dp);
+			sqcp->sd_dp = NULL;
+		}
+	}
+}
+
+static int scsi_debug_abort(struct scsi_cmnd *SCpnt)
+{
+	bool ok;
+
+	++num_aborts;
+	if (SCpnt) {
+		ok = stop_queued_cmnd(SCpnt);
+		if (SCpnt->device && (SDEBUG_OPT_ALL_NOISE & sdebug_opts))
+			sdev_printk(KERN_INFO, SCpnt->device,
+				    "%s: command%s found\n", __func__,
+				    ok ? "" : " not");
+	}
+	return SUCCESS;
+}
+
+static int scsi_debug_device_reset(struct scsi_cmnd *SCpnt)
+{
+	++num_dev_resets;
+	if (SCpnt && SCpnt->device) {
+		struct scsi_device *sdp = SCpnt->device;
+		struct sdebug_dev_info *devip =
+				(struct sdebug_dev_info *)sdp->hostdata;
+
+		if (SDEBUG_OPT_ALL_NOISE & sdebug_opts)
+			sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
+		if (devip)
+			set_bit(SDEBUG_UA_POR, devip->uas_bm);
+	}
+	return SUCCESS;
+}
+
+static int scsi_debug_target_reset(struct scsi_cmnd *SCpnt)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct sdebug_dev_info *devip;
+	struct scsi_device *sdp;
+	struct Scsi_Host *hp;
+	int k = 0;
+
+	++num_target_resets;
+	if (!SCpnt)
+		goto lie;
+	sdp = SCpnt->device;
+	if (!sdp)
+		goto lie;
+	if (SDEBUG_OPT_ALL_NOISE & sdebug_opts)
+		sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
+	hp = sdp->host;
+	if (!hp)
+		goto lie;
+	sdbg_host = *(struct sdebug_host_info **)shost_priv(hp);
+	if (sdbg_host) {
+		list_for_each_entry(devip,
+				    &sdbg_host->dev_info_list,
+				    dev_list)
+			if (devip->target == sdp->id) {
+				set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
+				++k;
+			}
+	}
+	if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
+		sdev_printk(KERN_INFO, sdp,
+			    "%s: %d device(s) found in target\n", __func__, k);
+lie:
+	return SUCCESS;
+}
+
+static int scsi_debug_bus_reset(struct scsi_cmnd *SCpnt)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct sdebug_dev_info *devip;
+	struct scsi_device *sdp;
+	struct Scsi_Host *hp;
+	int k = 0;
+
+	++num_bus_resets;
+	if (!(SCpnt && SCpnt->device))
+		goto lie;
+	sdp = SCpnt->device;
+	if (SDEBUG_OPT_ALL_NOISE & sdebug_opts)
+		sdev_printk(KERN_INFO, sdp, "%s\n", __func__);
+	hp = sdp->host;
+	if (hp) {
+		sdbg_host = *(struct sdebug_host_info **)shost_priv(hp);
+		if (sdbg_host) {
+			list_for_each_entry(devip,
+					    &sdbg_host->dev_info_list,
+					    dev_list) {
+				set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
+				++k;
+			}
+		}
+	}
+	if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
+		sdev_printk(KERN_INFO, sdp,
+			    "%s: %d device(s) found in host\n", __func__, k);
+lie:
+	return SUCCESS;
+}
+
+static int scsi_debug_host_reset(struct scsi_cmnd *SCpnt)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct sdebug_dev_info *devip;
+	int k = 0;
+
+	++num_host_resets;
+	if ((SCpnt->device) && (SDEBUG_OPT_ALL_NOISE & sdebug_opts))
+		sdev_printk(KERN_INFO, SCpnt->device, "%s\n", __func__);
+	spin_lock(&sdebug_host_list_lock);
+	list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
+		list_for_each_entry(devip, &sdbg_host->dev_info_list,
+				    dev_list) {
+			set_bit(SDEBUG_UA_BUS_RESET, devip->uas_bm);
+			++k;
+		}
+	}
+	spin_unlock(&sdebug_host_list_lock);
+	stop_all_queued();
+	if (SDEBUG_OPT_RESET_NOISE & sdebug_opts)
+		sdev_printk(KERN_INFO, SCpnt->device,
+			    "%s: %d device(s) found\n", __func__, k);
+	return SUCCESS;
+}
+
+static void __init sdebug_build_parts(unsigned char *ramp,
+				      unsigned long store_size)
+{
+	struct partition *pp;
+	int starts[SDEBUG_MAX_PARTS + 2];
+	int sectors_per_part, num_sectors, k;
+	int heads_by_sects, start_sec, end_sec;
+
+	/* assume partition table already zeroed */
+	if ((sdebug_num_parts < 1) || (store_size < 1048576))
+		return;
+	if (sdebug_num_parts > SDEBUG_MAX_PARTS) {
+		sdebug_num_parts = SDEBUG_MAX_PARTS;
+		pr_warn("reducing partitions to %d\n", SDEBUG_MAX_PARTS);
+	}
+	num_sectors = (int)sdebug_store_sectors;
+	sectors_per_part = (num_sectors - sdebug_sectors_per)
+			   / sdebug_num_parts;
+	heads_by_sects = sdebug_heads * sdebug_sectors_per;
+	starts[0] = sdebug_sectors_per;
+	for (k = 1; k < sdebug_num_parts; ++k)
+		starts[k] = ((k * sectors_per_part) / heads_by_sects)
+			    * heads_by_sects;
+	starts[sdebug_num_parts] = num_sectors;
+	starts[sdebug_num_parts + 1] = 0;
+
+	ramp[510] = 0x55;	/* magic partition markings */
+	ramp[511] = 0xAA;
+	pp = (struct partition *)(ramp + 0x1be);
+	for (k = 0; starts[k + 1]; ++k, ++pp) {
+		start_sec = starts[k];
+		end_sec = starts[k + 1] - 1;
+		pp->boot_ind = 0;
+
+		pp->cyl = start_sec / heads_by_sects;
+		pp->head = (start_sec - (pp->cyl * heads_by_sects))
+			   / sdebug_sectors_per;
+		pp->sector = (start_sec % sdebug_sectors_per) + 1;
+
+		pp->end_cyl = end_sec / heads_by_sects;
+		pp->end_head = (end_sec - (pp->end_cyl * heads_by_sects))
+			       / sdebug_sectors_per;
+		pp->end_sector = (end_sec % sdebug_sectors_per) + 1;
+
+		pp->start_sect = cpu_to_le32(start_sec);
+		pp->nr_sects = cpu_to_le32(end_sec - start_sec + 1);
+		pp->sys_ind = 0x83;	/* plain Linux partition */
+	}
+}
+
+static void block_unblock_all_queues(bool block)
+{
+	int j;
+	struct sdebug_queue *sqp;
+
+	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp)
+		atomic_set(&sqp->blocked, (int)block);
+}
+
+/* Adjust (by rounding down) the sdebug_cmnd_count so abs(every_nth)-1
+ * commands will be processed normally before triggers occur.
+ */
+static void tweak_cmnd_count(void)
+{
+	int count, modulo;
+
+	modulo = abs(sdebug_every_nth);
+	if (modulo < 2)
+		return;
+	block_unblock_all_queues(true);
+	count = atomic_read(&sdebug_cmnd_count);
+	atomic_set(&sdebug_cmnd_count, (count / modulo) * modulo);
+	block_unblock_all_queues(false);
+}
+
+static void clear_queue_stats(void)
+{
+	atomic_set(&sdebug_cmnd_count, 0);
+	atomic_set(&sdebug_completions, 0);
+	atomic_set(&sdebug_miss_cpus, 0);
+	atomic_set(&sdebug_a_tsf, 0);
+}
+
+static void setup_inject(struct sdebug_queue *sqp,
+			 struct sdebug_queued_cmd *sqcp)
+{
+	if ((atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) > 0) {
+		if (sdebug_every_nth > 0)
+			sqcp->inj_recovered = sqcp->inj_transport
+				= sqcp->inj_dif
+				= sqcp->inj_dix = sqcp->inj_short
+				= sqcp->inj_host_busy = sqcp->inj_cmd_abort = 0;
+		return;
+	}
+	sqcp->inj_recovered = !!(SDEBUG_OPT_RECOVERED_ERR & sdebug_opts);
+	sqcp->inj_transport = !!(SDEBUG_OPT_TRANSPORT_ERR & sdebug_opts);
+	sqcp->inj_dif = !!(SDEBUG_OPT_DIF_ERR & sdebug_opts);
+	sqcp->inj_dix = !!(SDEBUG_OPT_DIX_ERR & sdebug_opts);
+	sqcp->inj_short = !!(SDEBUG_OPT_SHORT_TRANSFER & sdebug_opts);
+	sqcp->inj_host_busy = !!(SDEBUG_OPT_HOST_BUSY & sdebug_opts);
+	sqcp->inj_cmd_abort = !!(SDEBUG_OPT_CMD_ABORT & sdebug_opts);
+}
+
+/* Complete the processing of the thread that queued a SCSI command to this
+ * driver. It either completes the command by calling cmnd_done() or
+ * schedules a hr timer or work queue then returns 0. Returns
+ * SCSI_MLQUEUE_HOST_BUSY if temporarily out of resources.
+ */
+static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip,
+			 int scsi_result,
+			 int (*pfp)(struct scsi_cmnd *,
+				    struct sdebug_dev_info *),
+			 int delta_jiff, int ndelay)
+{
+	unsigned long iflags;
+	int k, num_in_q, qdepth, inject;
+	struct sdebug_queue *sqp;
+	struct sdebug_queued_cmd *sqcp;
+	struct scsi_device *sdp;
+	struct sdebug_defer *sd_dp;
+
+	if (unlikely(devip == NULL)) {
+		if (scsi_result == 0)
+			scsi_result = DID_NO_CONNECT << 16;
+		goto respond_in_thread;
+	}
+	sdp = cmnd->device;
+
+	if (delta_jiff == 0)
+		goto respond_in_thread;
+
+	/* schedule the response at a later time if resources permit */
+	sqp = get_queue(cmnd);
+	spin_lock_irqsave(&sqp->qc_lock, iflags);
+	if (unlikely(atomic_read(&sqp->blocked))) {
+		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+		return SCSI_MLQUEUE_HOST_BUSY;
+	}
+	num_in_q = atomic_read(&devip->num_in_q);
+	qdepth = cmnd->device->queue_depth;
+	inject = 0;
+	if (unlikely((qdepth > 0) && (num_in_q >= qdepth))) {
+		if (scsi_result) {
+			spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+			goto respond_in_thread;
+		} else
+			scsi_result = device_qfull_result;
+	} else if (unlikely(sdebug_every_nth &&
+			    (SDEBUG_OPT_RARE_TSF & sdebug_opts) &&
+			    (scsi_result == 0))) {
+		if ((num_in_q == (qdepth - 1)) &&
+		    (atomic_inc_return(&sdebug_a_tsf) >=
+		     abs(sdebug_every_nth))) {
+			atomic_set(&sdebug_a_tsf, 0);
+			inject = 1;
+			scsi_result = device_qfull_result;
+		}
+	}
+
+	k = find_first_zero_bit(sqp->in_use_bm, sdebug_max_queue);
+	if (unlikely(k >= sdebug_max_queue)) {
+		spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+		if (scsi_result)
+			goto respond_in_thread;
+		else if (SDEBUG_OPT_ALL_TSF & sdebug_opts)
+			scsi_result = device_qfull_result;
+		if (SDEBUG_OPT_Q_NOISE & sdebug_opts)
+			sdev_printk(KERN_INFO, sdp,
+				    "%s: max_queue=%d exceeded, %s\n",
+				    __func__, sdebug_max_queue,
+				    (scsi_result ?  "status: TASK SET FULL" :
+						    "report: host busy"));
+		if (scsi_result)
+			goto respond_in_thread;
+		else
+			return SCSI_MLQUEUE_HOST_BUSY;
+	}
+	__set_bit(k, sqp->in_use_bm);
+	atomic_inc(&devip->num_in_q);
+	sqcp = &sqp->qc_arr[k];
+	sqcp->a_cmnd = cmnd;
+	cmnd->host_scribble = (unsigned char *)sqcp;
+	sd_dp = sqcp->sd_dp;
+	spin_unlock_irqrestore(&sqp->qc_lock, iflags);
+	if (unlikely(sdebug_every_nth && sdebug_any_injecting_opt))
+		setup_inject(sqp, sqcp);
+	if (sd_dp == NULL) {
+		sd_dp = kzalloc(sizeof(*sd_dp), GFP_ATOMIC);
+		if (sd_dp == NULL)
+			return SCSI_MLQUEUE_HOST_BUSY;
+	}
+
+	cmnd->result = pfp != NULL ? pfp(cmnd, devip) : 0;
+	if (cmnd->result & SDEG_RES_IMMED_MASK) {
+		/*
+		 * This is the F_DELAY_OVERR case. No delay.
+		 */
+		cmnd->result &= ~SDEG_RES_IMMED_MASK;
+		delta_jiff = ndelay = 0;
+	}
+	if (cmnd->result == 0 && scsi_result != 0)
+		cmnd->result = scsi_result;
+
+	if (unlikely(sdebug_verbose && cmnd->result))
+		sdev_printk(KERN_INFO, sdp, "%s: non-zero result=0x%x\n",
+			    __func__, cmnd->result);
+
+	if (delta_jiff > 0 || ndelay > 0) {
+		ktime_t kt;
+
+		if (delta_jiff > 0) {
+			kt = ns_to_ktime((u64)delta_jiff * (NSEC_PER_SEC / HZ));
+		} else
+			kt = ndelay;
+		if (!sd_dp->init_hrt) {
+			sd_dp->init_hrt = true;
+			sqcp->sd_dp = sd_dp;
+			hrtimer_init(&sd_dp->hrt, CLOCK_MONOTONIC,
+				     HRTIMER_MODE_REL_PINNED);
+			sd_dp->hrt.function = sdebug_q_cmd_hrt_complete;
+			sd_dp->sqa_idx = sqp - sdebug_q_arr;
+			sd_dp->qc_idx = k;
+		}
+		if (sdebug_statistics)
+			sd_dp->issuing_cpu = raw_smp_processor_id();
+		sd_dp->defer_t = SDEB_DEFER_HRT;
+		hrtimer_start(&sd_dp->hrt, kt, HRTIMER_MODE_REL_PINNED);
+	} else {	/* jdelay < 0, use work queue */
+		if (!sd_dp->init_wq) {
+			sd_dp->init_wq = true;
+			sqcp->sd_dp = sd_dp;
+			sd_dp->sqa_idx = sqp - sdebug_q_arr;
+			sd_dp->qc_idx = k;
+			INIT_WORK(&sd_dp->ew.work, sdebug_q_cmd_wq_complete);
+		}
+		if (sdebug_statistics)
+			sd_dp->issuing_cpu = raw_smp_processor_id();
+		sd_dp->defer_t = SDEB_DEFER_WQ;
+		if (unlikely(sqcp->inj_cmd_abort))
+			sd_dp->aborted = true;
+		schedule_work(&sd_dp->ew.work);
+		if (unlikely(sqcp->inj_cmd_abort)) {
+			sdev_printk(KERN_INFO, sdp, "abort request tag %d\n",
+				    cmnd->request->tag);
+			blk_abort_request(cmnd->request);
+		}
+	}
+	if (unlikely((SDEBUG_OPT_Q_NOISE & sdebug_opts) &&
+		     (scsi_result == device_qfull_result)))
+		sdev_printk(KERN_INFO, sdp,
+			    "%s: num_in_q=%d +1, %s%s\n", __func__,
+			    num_in_q, (inject ? "<inject> " : ""),
+			    "status: TASK SET FULL");
+	return 0;
+
+respond_in_thread:	/* call back to mid-layer using invocation thread */
+	cmnd->result = pfp != NULL ? pfp(cmnd, devip) : 0;
+	cmnd->result &= ~SDEG_RES_IMMED_MASK;
+	if (cmnd->result == 0 && scsi_result != 0)
+		cmnd->result = scsi_result;
+	cmnd->scsi_done(cmnd);
+	return 0;
+}
+
+/* Note: The following macros create attribute files in the
+   /sys/module/scsi_debug/parameters directory. Unfortunately this
+   driver is unaware of a change and cannot trigger auxiliary actions
+   as it can when the corresponding attribute in the
+   /sys/bus/pseudo/drivers/scsi_debug directory is changed.
+ */
+module_param_named(add_host, sdebug_add_host, int, S_IRUGO | S_IWUSR);
+module_param_named(ato, sdebug_ato, int, S_IRUGO);
+module_param_named(cdb_len, sdebug_cdb_len, int, 0644);
+module_param_named(clustering, sdebug_clustering, bool, S_IRUGO | S_IWUSR);
+module_param_named(delay, sdebug_jdelay, int, S_IRUGO | S_IWUSR);
+module_param_named(dev_size_mb, sdebug_dev_size_mb, int, S_IRUGO);
+module_param_named(dif, sdebug_dif, int, S_IRUGO);
+module_param_named(dix, sdebug_dix, int, S_IRUGO);
+module_param_named(dsense, sdebug_dsense, int, S_IRUGO | S_IWUSR);
+module_param_named(every_nth, sdebug_every_nth, int, S_IRUGO | S_IWUSR);
+module_param_named(fake_rw, sdebug_fake_rw, int, S_IRUGO | S_IWUSR);
+module_param_named(guard, sdebug_guard, uint, S_IRUGO);
+module_param_named(host_lock, sdebug_host_lock, bool, S_IRUGO | S_IWUSR);
+module_param_string(inq_vendor, sdebug_inq_vendor_id,
+		    sizeof(sdebug_inq_vendor_id), S_IRUGO|S_IWUSR);
+module_param_string(inq_product, sdebug_inq_product_id,
+		    sizeof(sdebug_inq_product_id), S_IRUGO|S_IWUSR);
+module_param_string(inq_rev, sdebug_inq_product_rev,
+		    sizeof(sdebug_inq_product_rev), S_IRUGO|S_IWUSR);
+module_param_named(lbpu, sdebug_lbpu, int, S_IRUGO);
+module_param_named(lbpws, sdebug_lbpws, int, S_IRUGO);
+module_param_named(lbpws10, sdebug_lbpws10, int, S_IRUGO);
+module_param_named(lbprz, sdebug_lbprz, int, S_IRUGO);
+module_param_named(lowest_aligned, sdebug_lowest_aligned, int, S_IRUGO);
+module_param_named(max_luns, sdebug_max_luns, int, S_IRUGO | S_IWUSR);
+module_param_named(max_queue, sdebug_max_queue, int, S_IRUGO | S_IWUSR);
+module_param_named(medium_error_start, sdebug_medium_error_start, int, S_IRUGO | S_IWUSR);
+module_param_named(medium_error_count, sdebug_medium_error_count, int, S_IRUGO | S_IWUSR);
+module_param_named(ndelay, sdebug_ndelay, int, S_IRUGO | S_IWUSR);
+module_param_named(no_lun_0, sdebug_no_lun_0, int, S_IRUGO | S_IWUSR);
+module_param_named(no_uld, sdebug_no_uld, int, S_IRUGO);
+module_param_named(num_parts, sdebug_num_parts, int, S_IRUGO);
+module_param_named(num_tgts, sdebug_num_tgts, int, S_IRUGO | S_IWUSR);
+module_param_named(opt_blks, sdebug_opt_blks, int, S_IRUGO);
+module_param_named(opts, sdebug_opts, int, S_IRUGO | S_IWUSR);
+module_param_named(physblk_exp, sdebug_physblk_exp, int, S_IRUGO);
+module_param_named(opt_xferlen_exp, sdebug_opt_xferlen_exp, int, S_IRUGO);
+module_param_named(ptype, sdebug_ptype, int, S_IRUGO | S_IWUSR);
+module_param_named(removable, sdebug_removable, bool, S_IRUGO | S_IWUSR);
+module_param_named(scsi_level, sdebug_scsi_level, int, S_IRUGO);
+module_param_named(sector_size, sdebug_sector_size, int, S_IRUGO);
+module_param_named(statistics, sdebug_statistics, bool, S_IRUGO | S_IWUSR);
+module_param_named(strict, sdebug_strict, bool, S_IRUGO | S_IWUSR);
+module_param_named(submit_queues, submit_queues, int, S_IRUGO);
+module_param_named(unmap_alignment, sdebug_unmap_alignment, int, S_IRUGO);
+module_param_named(unmap_granularity, sdebug_unmap_granularity, int, S_IRUGO);
+module_param_named(unmap_max_blocks, sdebug_unmap_max_blocks, int, S_IRUGO);
+module_param_named(unmap_max_desc, sdebug_unmap_max_desc, int, S_IRUGO);
+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(write_same_length, sdebug_write_same_length, int,
+		   S_IRUGO | S_IWUSR);
+
+MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
+MODULE_DESCRIPTION("SCSI debug adapter driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(SDEBUG_VERSION);
+
+MODULE_PARM_DESC(add_host, "0..127 hosts allowed(def=1)");
+MODULE_PARM_DESC(ato, "application tag ownership: 0=disk 1=host (def=1)");
+MODULE_PARM_DESC(cdb_len, "suggest CDB lengths to drivers (def=10)");
+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 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)");
+MODULE_PARM_DESC(every_nth, "timeout every nth command(def=0)");
+MODULE_PARM_DESC(fake_rw, "fake reads/writes instead of copying (def=0)");
+MODULE_PARM_DESC(guard, "protection checksum: 0=crc, 1=ip (def=0)");
+MODULE_PARM_DESC(host_lock, "host_lock is ignored (def=0)");
+MODULE_PARM_DESC(inq_vendor, "SCSI INQUIRY vendor string (def=\"Linux\")");
+MODULE_PARM_DESC(inq_product, "SCSI INQUIRY product string (def=\"scsi_debug\")");
+MODULE_PARM_DESC(inq_rev, "SCSI INQUIRY revision string (def=\""
+		 SDEBUG_VERSION "\")");
+MODULE_PARM_DESC(lbpu, "enable LBP, support UNMAP command (def=0)");
+MODULE_PARM_DESC(lbpws, "enable LBP, support WRITE SAME(16) with UNMAP bit (def=0)");
+MODULE_PARM_DESC(lbpws10, "enable LBP, support WRITE SAME(10) with UNMAP bit (def=0)");
+MODULE_PARM_DESC(lbprz,
+	"on read unmapped LBs return 0 when 1 (def), return 0xff when 2");
+MODULE_PARM_DESC(lowest_aligned, "lowest aligned lba (def=0)");
+MODULE_PARM_DESC(max_luns, "number of LUNs per target to simulate(def=1)");
+MODULE_PARM_DESC(max_queue, "max number of queued commands (1 to max(def))");
+MODULE_PARM_DESC(medium_error_start, "starting sector number to return MEDIUM error");
+MODULE_PARM_DESC(medium_error_count, "count of sectors to return follow on MEDIUM error");
+MODULE_PARM_DESC(ndelay, "response delay in nanoseconds (def=0 -> ignore)");
+MODULE_PARM_DESC(no_lun_0, "no LU number 0 (def=0 -> have lun 0)");
+MODULE_PARM_DESC(no_uld, "stop ULD (e.g. sd driver) attaching (def=0))");
+MODULE_PARM_DESC(num_parts, "number of partitions(def=0)");
+MODULE_PARM_DESC(num_tgts, "number of targets per host to simulate(def=1)");
+MODULE_PARM_DESC(opt_blks, "optimal transfer length in blocks (def=1024)");
+MODULE_PARM_DESC(opts, "1->noise, 2->medium_err, 4->timeout, 8->recovered_err... (def=0)");
+MODULE_PARM_DESC(physblk_exp, "physical block exponent (def=0)");
+MODULE_PARM_DESC(opt_xferlen_exp, "optimal transfer length granularity exponent (def=physblk_exp)");
+MODULE_PARM_DESC(ptype, "SCSI peripheral type(def=0[disk])");
+MODULE_PARM_DESC(removable, "claim to have removable media (def=0)");
+MODULE_PARM_DESC(scsi_level, "SCSI level to simulate(def=7[SPC-5])");
+MODULE_PARM_DESC(sector_size, "logical block size in bytes (def=512)");
+MODULE_PARM_DESC(statistics, "collect statistics on commands, queues (def=0)");
+MODULE_PARM_DESC(strict, "stricter checks: reserved field in cdb (def=0)");
+MODULE_PARM_DESC(submit_queues, "support for block multi-queue (def=1)");
+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(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(write_same_length, "Maximum blocks per WRITE SAME cmd (def=0xffff)");
+
+#define SDEBUG_INFO_LEN 256
+static char sdebug_info[SDEBUG_INFO_LEN];
+
+static const char *scsi_debug_info(struct Scsi_Host *shp)
+{
+	int k;
+
+	k = scnprintf(sdebug_info, SDEBUG_INFO_LEN, "%s: version %s [%s]\n",
+		      my_name, SDEBUG_VERSION, sdebug_version_date);
+	if (k >= (SDEBUG_INFO_LEN - 1))
+		return sdebug_info;
+	scnprintf(sdebug_info + k, SDEBUG_INFO_LEN - k,
+		  "  dev_size_mb=%d, opts=0x%x, submit_queues=%d, %s=%d",
+		  sdebug_dev_size_mb, sdebug_opts, submit_queues,
+		  "statistics", (int)sdebug_statistics);
+	return sdebug_info;
+}
+
+/* 'echo <val> > /proc/scsi/scsi_debug/<host_id>' writes to opts */
+static int scsi_debug_write_info(struct Scsi_Host *host, char *buffer,
+				 int length)
+{
+	char arr[16];
+	int opts;
+	int minLen = length > 15 ? 15 : length;
+
+	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
+		return -EACCES;
+	memcpy(arr, buffer, minLen);
+	arr[minLen] = '\0';
+	if (1 != sscanf(arr, "%d", &opts))
+		return -EINVAL;
+	sdebug_opts = opts;
+	sdebug_verbose = !!(SDEBUG_OPT_NOISE & opts);
+	sdebug_any_injecting_opt = !!(SDEBUG_OPT_ALL_INJECTING & opts);
+	if (sdebug_every_nth != 0)
+		tweak_cmnd_count();
+	return length;
+}
+
+/* Output seen with 'cat /proc/scsi/scsi_debug/<host_id>'. It will be the
+ * same for each scsi_debug host (if more than one). Some of the counters
+ * output are not atomics so might be inaccurate in a busy system. */
+static int scsi_debug_show_info(struct seq_file *m, struct Scsi_Host *host)
+{
+	int f, j, l;
+	struct sdebug_queue *sqp;
+
+	seq_printf(m, "scsi_debug adapter driver, version %s [%s]\n",
+		   SDEBUG_VERSION, sdebug_version_date);
+	seq_printf(m, "num_tgts=%d, %ssize=%d MB, opts=0x%x, every_nth=%d\n",
+		   sdebug_num_tgts, "shared (ram) ", sdebug_dev_size_mb,
+		   sdebug_opts, sdebug_every_nth);
+	seq_printf(m, "delay=%d, ndelay=%d, max_luns=%d, sector_size=%d %s\n",
+		   sdebug_jdelay, sdebug_ndelay, sdebug_max_luns,
+		   sdebug_sector_size, "bytes");
+	seq_printf(m, "cylinders=%d, heads=%d, sectors=%d, command aborts=%d\n",
+		   sdebug_cylinders_per, sdebug_heads, sdebug_sectors_per,
+		   num_aborts);
+	seq_printf(m, "RESETs: device=%d, target=%d, bus=%d, host=%d\n",
+		   num_dev_resets, num_target_resets, num_bus_resets,
+		   num_host_resets);
+	seq_printf(m, "dix_reads=%d, dix_writes=%d, dif_errors=%d\n",
+		   dix_reads, dix_writes, dif_errors);
+	seq_printf(m, "usec_in_jiffy=%lu, statistics=%d\n", TICK_NSEC / 1000,
+		   sdebug_statistics);
+	seq_printf(m, "cmnd_count=%d, completions=%d, %s=%d, a_tsf=%d\n",
+		   atomic_read(&sdebug_cmnd_count),
+		   atomic_read(&sdebug_completions),
+		   "miss_cpus", atomic_read(&sdebug_miss_cpus),
+		   atomic_read(&sdebug_a_tsf));
+
+	seq_printf(m, "submit_queues=%d\n", submit_queues);
+	for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) {
+		seq_printf(m, "  queue %d:\n", j);
+		f = find_first_bit(sqp->in_use_bm, sdebug_max_queue);
+		if (f != sdebug_max_queue) {
+			l = find_last_bit(sqp->in_use_bm, sdebug_max_queue);
+			seq_printf(m, "    in_use_bm BUSY: %s: %d,%d\n",
+				   "first,last bits", f, l);
+		}
+	}
+	return 0;
+}
+
+static ssize_t delay_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_jdelay);
+}
+/* Returns -EBUSY if jdelay is being changed and commands are queued. The unit
+ * of delay is jiffies.
+ */
+static ssize_t delay_store(struct device_driver *ddp, const char *buf,
+			   size_t count)
+{
+	int jdelay, res;
+
+	if (count > 0 && sscanf(buf, "%d", &jdelay) == 1) {
+		res = count;
+		if (sdebug_jdelay != jdelay) {
+			int j, k;
+			struct sdebug_queue *sqp;
+
+			block_unblock_all_queues(true);
+			for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
+			     ++j, ++sqp) {
+				k = find_first_bit(sqp->in_use_bm,
+						   sdebug_max_queue);
+				if (k != sdebug_max_queue) {
+					res = -EBUSY;   /* queued commands */
+					break;
+				}
+			}
+			if (res > 0) {
+				sdebug_jdelay = jdelay;
+				sdebug_ndelay = 0;
+			}
+			block_unblock_all_queues(false);
+		}
+		return res;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(delay);
+
+static ssize_t ndelay_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_ndelay);
+}
+/* Returns -EBUSY if ndelay is being changed and commands are queued */
+/* If > 0 and accepted then sdebug_jdelay is set to JDELAY_OVERRIDDEN */
+static ssize_t ndelay_store(struct device_driver *ddp, const char *buf,
+			    size_t count)
+{
+	int ndelay, res;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &ndelay)) &&
+	    (ndelay >= 0) && (ndelay < (1000 * 1000 * 1000))) {
+		res = count;
+		if (sdebug_ndelay != ndelay) {
+			int j, k;
+			struct sdebug_queue *sqp;
+
+			block_unblock_all_queues(true);
+			for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
+			     ++j, ++sqp) {
+				k = find_first_bit(sqp->in_use_bm,
+						   sdebug_max_queue);
+				if (k != sdebug_max_queue) {
+					res = -EBUSY;   /* queued commands */
+					break;
+				}
+			}
+			if (res > 0) {
+				sdebug_ndelay = ndelay;
+				sdebug_jdelay = ndelay  ? JDELAY_OVERRIDDEN
+							: DEF_JDELAY;
+			}
+			block_unblock_all_queues(false);
+		}
+		return res;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(ndelay);
+
+static ssize_t opts_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "0x%x\n", sdebug_opts);
+}
+
+static ssize_t opts_store(struct device_driver *ddp, const char *buf,
+			  size_t count)
+{
+	int opts;
+	char work[20];
+
+	if (sscanf(buf, "%10s", work) == 1) {
+		if (strncasecmp(work, "0x", 2) == 0) {
+			if (kstrtoint(work + 2, 16, &opts) == 0)
+				goto opts_done;
+		} else {
+			if (kstrtoint(work, 10, &opts) == 0)
+				goto opts_done;
+		}
+	}
+	return -EINVAL;
+opts_done:
+	sdebug_opts = opts;
+	sdebug_verbose = !!(SDEBUG_OPT_NOISE & opts);
+	sdebug_any_injecting_opt = !!(SDEBUG_OPT_ALL_INJECTING & opts);
+	tweak_cmnd_count();
+	return count;
+}
+static DRIVER_ATTR_RW(opts);
+
+static ssize_t ptype_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_ptype);
+}
+static ssize_t ptype_store(struct device_driver *ddp, const char *buf,
+			   size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_ptype = n;
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(ptype);
+
+static ssize_t dsense_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dsense);
+}
+static ssize_t dsense_store(struct device_driver *ddp, const char *buf,
+			    size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_dsense = n;
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(dsense);
+
+static ssize_t fake_rw_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_fake_rw);
+}
+static ssize_t fake_rw_store(struct device_driver *ddp, const char *buf,
+			     size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		n = (n > 0);
+		sdebug_fake_rw = (sdebug_fake_rw > 0);
+		if (sdebug_fake_rw != n) {
+			if ((0 == n) && (NULL == fake_storep)) {
+				unsigned long sz =
+					(unsigned long)sdebug_dev_size_mb *
+					1048576;
+
+				fake_storep = vzalloc(sz);
+				if (NULL == fake_storep) {
+					pr_err("out of memory, 9\n");
+					return -ENOMEM;
+				}
+			}
+			sdebug_fake_rw = n;
+		}
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(fake_rw);
+
+static ssize_t no_lun_0_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_no_lun_0);
+}
+static ssize_t no_lun_0_store(struct device_driver *ddp, const char *buf,
+			      size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_no_lun_0 = n;
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(no_lun_0);
+
+static ssize_t num_tgts_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_tgts);
+}
+static ssize_t num_tgts_store(struct device_driver *ddp, const char *buf,
+			      size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_num_tgts = n;
+		sdebug_max_tgts_luns();
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(num_tgts);
+
+static ssize_t dev_size_mb_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dev_size_mb);
+}
+static DRIVER_ATTR_RO(dev_size_mb);
+
+static ssize_t num_parts_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_parts);
+}
+static DRIVER_ATTR_RO(num_parts);
+
+static ssize_t every_nth_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_every_nth);
+}
+static ssize_t every_nth_store(struct device_driver *ddp, const char *buf,
+			       size_t count)
+{
+	int nth;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &nth))) {
+		sdebug_every_nth = nth;
+		if (nth && !sdebug_statistics) {
+			pr_info("every_nth needs statistics=1, set it\n");
+			sdebug_statistics = true;
+		}
+		tweak_cmnd_count();
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(every_nth);
+
+static ssize_t max_luns_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_max_luns);
+}
+static ssize_t max_luns_store(struct device_driver *ddp, const char *buf,
+			      size_t count)
+{
+	int n;
+	bool changed;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		if (n > 256) {
+			pr_warn("max_luns can be no more than 256\n");
+			return -EINVAL;
+		}
+		changed = (sdebug_max_luns != n);
+		sdebug_max_luns = n;
+		sdebug_max_tgts_luns();
+		if (changed && (sdebug_scsi_level >= 5)) {	/* >= SPC-3 */
+			struct sdebug_host_info *sdhp;
+			struct sdebug_dev_info *dp;
+
+			spin_lock(&sdebug_host_list_lock);
+			list_for_each_entry(sdhp, &sdebug_host_list,
+					    host_list) {
+				list_for_each_entry(dp, &sdhp->dev_info_list,
+						    dev_list) {
+					set_bit(SDEBUG_UA_LUNS_CHANGED,
+						dp->uas_bm);
+				}
+			}
+			spin_unlock(&sdebug_host_list_lock);
+		}
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(max_luns);
+
+static ssize_t max_queue_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_max_queue);
+}
+/* N.B. max_queue can be changed while there are queued commands. In flight
+ * commands beyond the new max_queue will be completed. */
+static ssize_t max_queue_store(struct device_driver *ddp, const char *buf,
+			       size_t count)
+{
+	int j, n, k, a;
+	struct sdebug_queue *sqp;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n > 0) &&
+	    (n <= SDEBUG_CANQUEUE)) {
+		block_unblock_all_queues(true);
+		k = 0;
+		for (j = 0, sqp = sdebug_q_arr; j < submit_queues;
+		     ++j, ++sqp) {
+			a = find_last_bit(sqp->in_use_bm, SDEBUG_CANQUEUE);
+			if (a > k)
+				k = a;
+		}
+		sdebug_max_queue = n;
+		if (k == SDEBUG_CANQUEUE)
+			atomic_set(&retired_max_queue, 0);
+		else if (k >= n)
+			atomic_set(&retired_max_queue, k + 1);
+		else
+			atomic_set(&retired_max_queue, 0);
+		block_unblock_all_queues(false);
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(max_queue);
+
+static ssize_t no_uld_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_no_uld);
+}
+static DRIVER_ATTR_RO(no_uld);
+
+static ssize_t scsi_level_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_scsi_level);
+}
+static DRIVER_ATTR_RO(scsi_level);
+
+static ssize_t virtual_gb_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_virtual_gb);
+}
+static ssize_t virtual_gb_store(struct device_driver *ddp, const char *buf,
+				size_t count)
+{
+	int n;
+	bool changed;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		changed = (sdebug_virtual_gb != n);
+		sdebug_virtual_gb = n;
+		sdebug_capacity = get_sdebug_capacity();
+		if (changed) {
+			struct sdebug_host_info *sdhp;
+			struct sdebug_dev_info *dp;
+
+			spin_lock(&sdebug_host_list_lock);
+			list_for_each_entry(sdhp, &sdebug_host_list,
+					    host_list) {
+				list_for_each_entry(dp, &sdhp->dev_info_list,
+						    dev_list) {
+					set_bit(SDEBUG_UA_CAPACITY_CHANGED,
+						dp->uas_bm);
+				}
+			}
+			spin_unlock(&sdebug_host_list_lock);
+		}
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(virtual_gb);
+
+static ssize_t add_host_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_add_host);
+}
+
+static int sdebug_add_adapter(void);
+static void sdebug_remove_adapter(void);
+
+static ssize_t add_host_store(struct device_driver *ddp, const char *buf,
+			      size_t count)
+{
+	int delta_hosts;
+
+	if (sscanf(buf, "%d", &delta_hosts) != 1)
+		return -EINVAL;
+	if (delta_hosts > 0) {
+		do {
+			sdebug_add_adapter();
+		} while (--delta_hosts);
+	} else if (delta_hosts < 0) {
+		do {
+			sdebug_remove_adapter();
+		} while (++delta_hosts);
+	}
+	return count;
+}
+static DRIVER_ATTR_RW(add_host);
+
+static ssize_t vpd_use_hostno_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_vpd_use_hostno);
+}
+static ssize_t vpd_use_hostno_store(struct device_driver *ddp, const char *buf,
+				    size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_vpd_use_hostno = n;
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(vpd_use_hostno);
+
+static ssize_t statistics_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", (int)sdebug_statistics);
+}
+static ssize_t statistics_store(struct device_driver *ddp, const char *buf,
+				size_t count)
+{
+	int n;
+
+	if ((count > 0) && (sscanf(buf, "%d", &n) == 1) && (n >= 0)) {
+		if (n > 0)
+			sdebug_statistics = true;
+		else {
+			clear_queue_stats();
+			sdebug_statistics = false;
+		}
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(statistics);
+
+static ssize_t sector_size_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%u\n", sdebug_sector_size);
+}
+static DRIVER_ATTR_RO(sector_size);
+
+static ssize_t submit_queues_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", submit_queues);
+}
+static DRIVER_ATTR_RO(submit_queues);
+
+static ssize_t dix_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dix);
+}
+static DRIVER_ATTR_RO(dix);
+
+static ssize_t dif_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_dif);
+}
+static DRIVER_ATTR_RO(dif);
+
+static ssize_t guard_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%u\n", sdebug_guard);
+}
+static DRIVER_ATTR_RO(guard);
+
+static ssize_t ato_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_ato);
+}
+static DRIVER_ATTR_RO(ato);
+
+static ssize_t map_show(struct device_driver *ddp, char *buf)
+{
+	ssize_t count;
+
+	if (!scsi_debug_lbp())
+		return scnprintf(buf, PAGE_SIZE, "0-%u\n",
+				 sdebug_store_sectors);
+
+	count = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
+			  (int)map_size, map_storep);
+	buf[count++] = '\n';
+	buf[count] = '\0';
+
+	return count;
+}
+static DRIVER_ATTR_RO(map);
+
+static ssize_t removable_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_removable ? 1 : 0);
+}
+static ssize_t removable_store(struct device_driver *ddp, const char *buf,
+			       size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_removable = (n > 0);
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(removable);
+
+static ssize_t host_lock_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!sdebug_host_lock);
+}
+/* N.B. sdebug_host_lock does nothing, kept for backward compatibility */
+static ssize_t host_lock_store(struct device_driver *ddp, const char *buf,
+			       size_t count)
+{
+	int n;
+
+	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
+		sdebug_host_lock = (n > 0);
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(host_lock);
+
+static ssize_t strict_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!sdebug_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)) {
+		sdebug_strict = (n > 0);
+		return count;
+	}
+	return -EINVAL;
+}
+static DRIVER_ATTR_RW(strict);
+
+static ssize_t uuid_ctl_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", !!sdebug_uuid_ctl);
+}
+static DRIVER_ATTR_RO(uuid_ctl);
+
+static ssize_t cdb_len_show(struct device_driver *ddp, char *buf)
+{
+	return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_cdb_len);
+}
+static ssize_t cdb_len_store(struct device_driver *ddp, const char *buf,
+			     size_t count)
+{
+	int ret, n;
+
+	ret = kstrtoint(buf, 0, &n);
+	if (ret)
+		return ret;
+	sdebug_cdb_len = n;
+	all_config_cdb_len();
+	return count;
+}
+static DRIVER_ATTR_RW(cdb_len);
+
+
+/* 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
+   directory) is that auxiliary actions can be triggered when an attribute
+   is changed. For example see: sdebug_add_host_store() above.
+ */
+
+static struct attribute *sdebug_drv_attrs[] = {
+	&driver_attr_delay.attr,
+	&driver_attr_opts.attr,
+	&driver_attr_ptype.attr,
+	&driver_attr_dsense.attr,
+	&driver_attr_fake_rw.attr,
+	&driver_attr_no_lun_0.attr,
+	&driver_attr_num_tgts.attr,
+	&driver_attr_dev_size_mb.attr,
+	&driver_attr_num_parts.attr,
+	&driver_attr_every_nth.attr,
+	&driver_attr_max_luns.attr,
+	&driver_attr_max_queue.attr,
+	&driver_attr_no_uld.attr,
+	&driver_attr_scsi_level.attr,
+	&driver_attr_virtual_gb.attr,
+	&driver_attr_add_host.attr,
+	&driver_attr_vpd_use_hostno.attr,
+	&driver_attr_sector_size.attr,
+	&driver_attr_statistics.attr,
+	&driver_attr_submit_queues.attr,
+	&driver_attr_dix.attr,
+	&driver_attr_dif.attr,
+	&driver_attr_guard.attr,
+	&driver_attr_ato.attr,
+	&driver_attr_map.attr,
+	&driver_attr_removable.attr,
+	&driver_attr_host_lock.attr,
+	&driver_attr_ndelay.attr,
+	&driver_attr_strict.attr,
+	&driver_attr_uuid_ctl.attr,
+	&driver_attr_cdb_len.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(sdebug_drv);
+
+static struct device *pseudo_primary;
+
+static int __init scsi_debug_init(void)
+{
+	unsigned long sz;
+	int host_to_add;
+	int k;
+	int ret;
+
+	atomic_set(&retired_max_queue, 0);
+
+	if (sdebug_ndelay >= 1000 * 1000 * 1000) {
+		pr_warn("ndelay must be less than 1 second, ignored\n");
+		sdebug_ndelay = 0;
+	} else if (sdebug_ndelay > 0)
+		sdebug_jdelay = JDELAY_OVERRIDDEN;
+
+	switch (sdebug_sector_size) {
+	case  512:
+	case 1024:
+	case 2048:
+	case 4096:
+		break;
+	default:
+		pr_err("invalid sector_size %d\n", sdebug_sector_size);
+		return -EINVAL;
+	}
+
+	switch (sdebug_dif) {
+	case T10_PI_TYPE0_PROTECTION:
+		break;
+	case T10_PI_TYPE1_PROTECTION:
+	case T10_PI_TYPE2_PROTECTION:
+	case T10_PI_TYPE3_PROTECTION:
+		have_dif_prot = true;
+		break;
+
+	default:
+		pr_err("dif must be 0, 1, 2 or 3\n");
+		return -EINVAL;
+	}
+
+	if (sdebug_num_tgts < 0) {
+		pr_err("num_tgts must be >= 0\n");
+		return -EINVAL;
+	}
+
+	if (sdebug_guard > 1) {
+		pr_err("guard must be 0 or 1\n");
+		return -EINVAL;
+	}
+
+	if (sdebug_ato > 1) {
+		pr_err("ato must be 0 or 1\n");
+		return -EINVAL;
+	}
+
+	if (sdebug_physblk_exp > 15) {
+		pr_err("invalid physblk_exp %u\n", sdebug_physblk_exp);
+		return -EINVAL;
+	}
+	if (sdebug_max_luns > 256) {
+		pr_warn("max_luns can be no more than 256, use default\n");
+		sdebug_max_luns = DEF_MAX_LUNS;
+	}
+
+	if (sdebug_lowest_aligned > 0x3fff) {
+		pr_err("lowest_aligned too big: %u\n", sdebug_lowest_aligned);
+		return -EINVAL;
+	}
+
+	if (submit_queues < 1) {
+		pr_err("submit_queues must be 1 or more\n");
+		return -EINVAL;
+	}
+
+	if ((sdebug_max_queue > SDEBUG_CANQUEUE) || (sdebug_max_queue < 1)) {
+		pr_err("max_queue must be in range [1, %d]\n", SDEBUG_CANQUEUE);
+		return -EINVAL;
+	}
+
+	sdebug_q_arr = kcalloc(submit_queues, sizeof(struct sdebug_queue),
+			       GFP_KERNEL);
+	if (sdebug_q_arr == NULL)
+		return -ENOMEM;
+	for (k = 0; k < submit_queues; ++k)
+		spin_lock_init(&sdebug_q_arr[k].qc_lock);
+
+	if (sdebug_dev_size_mb < 1)
+		sdebug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
+	sz = (unsigned long)sdebug_dev_size_mb * 1048576;
+	sdebug_store_sectors = sz / sdebug_sector_size;
+	sdebug_capacity = get_sdebug_capacity();
+
+	/* play around with geometry, don't waste too much on track 0 */
+	sdebug_heads = 8;
+	sdebug_sectors_per = 32;
+	if (sdebug_dev_size_mb >= 256)
+		sdebug_heads = 64;
+	else if (sdebug_dev_size_mb >= 16)
+		sdebug_heads = 32;
+	sdebug_cylinders_per = (unsigned long)sdebug_capacity /
+			       (sdebug_sectors_per * sdebug_heads);
+	if (sdebug_cylinders_per >= 1024) {
+		/* other LLDs do this; implies >= 1GB ram disk ... */
+		sdebug_heads = 255;
+		sdebug_sectors_per = 63;
+		sdebug_cylinders_per = (unsigned long)sdebug_capacity /
+			       (sdebug_sectors_per * sdebug_heads);
+	}
+
+	if (sdebug_fake_rw == 0) {
+		fake_storep = vzalloc(sz);
+		if (NULL == fake_storep) {
+			pr_err("out of memory, 1\n");
+			ret = -ENOMEM;
+			goto free_q_arr;
+		}
+		if (sdebug_num_parts > 0)
+			sdebug_build_parts(fake_storep, sz);
+	}
+
+	if (sdebug_dix) {
+		int dif_size;
+
+		dif_size = sdebug_store_sectors * sizeof(struct t10_pi_tuple);
+		dif_storep = vmalloc(dif_size);
+
+		pr_err("dif_storep %u bytes @ %p\n", dif_size, dif_storep);
+
+		if (dif_storep == NULL) {
+			pr_err("out of mem. (DIX)\n");
+			ret = -ENOMEM;
+			goto free_vm;
+		}
+
+		memset(dif_storep, 0xff, dif_size);
+	}
+
+	/* Logical Block Provisioning */
+	if (scsi_debug_lbp()) {
+		sdebug_unmap_max_blocks =
+			clamp(sdebug_unmap_max_blocks, 0U, 0xffffffffU);
+
+		sdebug_unmap_max_desc =
+			clamp(sdebug_unmap_max_desc, 0U, 256U);
+
+		sdebug_unmap_granularity =
+			clamp(sdebug_unmap_granularity, 1U, 0xffffffffU);
+
+		if (sdebug_unmap_alignment &&
+		    sdebug_unmap_granularity <=
+		    sdebug_unmap_alignment) {
+			pr_err("ERR: unmap_granularity <= unmap_alignment\n");
+			ret = -EINVAL;
+			goto free_vm;
+		}
+
+		map_size = lba_to_map_index(sdebug_store_sectors - 1) + 1;
+		map_storep = vmalloc(array_size(sizeof(long),
+						BITS_TO_LONGS(map_size)));
+
+		pr_info("%lu provisioning blocks\n", map_size);
+
+		if (map_storep == NULL) {
+			pr_err("out of mem. (MAP)\n");
+			ret = -ENOMEM;
+			goto free_vm;
+		}
+
+		bitmap_zero(map_storep, map_size);
+
+		/* Map first 1KB for partition table */
+		if (sdebug_num_parts)
+			map_region(0, 2);
+	}
+
+	pseudo_primary = root_device_register("pseudo_0");
+	if (IS_ERR(pseudo_primary)) {
+		pr_warn("root_device_register() error\n");
+		ret = PTR_ERR(pseudo_primary);
+		goto free_vm;
+	}
+	ret = bus_register(&pseudo_lld_bus);
+	if (ret < 0) {
+		pr_warn("bus_register error: %d\n", ret);
+		goto dev_unreg;
+	}
+	ret = driver_register(&sdebug_driverfs_driver);
+	if (ret < 0) {
+		pr_warn("driver_register error: %d\n", ret);
+		goto bus_unreg;
+	}
+
+	host_to_add = sdebug_add_host;
+	sdebug_add_host = 0;
+
+	for (k = 0; k < host_to_add; k++) {
+		if (sdebug_add_adapter()) {
+			pr_err("sdebug_add_adapter failed k=%d\n", k);
+			break;
+		}
+	}
+
+	if (sdebug_verbose)
+		pr_info("built %d host(s)\n", sdebug_add_host);
+
+	return 0;
+
+bus_unreg:
+	bus_unregister(&pseudo_lld_bus);
+dev_unreg:
+	root_device_unregister(pseudo_primary);
+free_vm:
+	vfree(map_storep);
+	vfree(dif_storep);
+	vfree(fake_storep);
+free_q_arr:
+	kfree(sdebug_q_arr);
+	return ret;
+}
+
+static void __exit scsi_debug_exit(void)
+{
+	int k = sdebug_add_host;
+
+	stop_all_queued();
+	for (; k; k--)
+		sdebug_remove_adapter();
+	free_all_queued();
+	driver_unregister(&sdebug_driverfs_driver);
+	bus_unregister(&pseudo_lld_bus);
+	root_device_unregister(pseudo_primary);
+
+	vfree(map_storep);
+	vfree(dif_storep);
+	vfree(fake_storep);
+	kfree(sdebug_q_arr);
+}
+
+device_initcall(scsi_debug_init);
+module_exit(scsi_debug_exit);
+
+static void sdebug_release_adapter(struct device *dev)
+{
+	struct sdebug_host_info *sdbg_host;
+
+	sdbg_host = to_sdebug_host(dev);
+	kfree(sdbg_host);
+}
+
+static int sdebug_add_adapter(void)
+{
+	int k, devs_per_host;
+	int error = 0;
+	struct sdebug_host_info *sdbg_host;
+	struct sdebug_dev_info *sdbg_devinfo, *tmp;
+
+	sdbg_host = kzalloc(sizeof(*sdbg_host), GFP_KERNEL);
+	if (sdbg_host == NULL) {
+		pr_err("out of memory at line %d\n", __LINE__);
+		return -ENOMEM;
+	}
+
+	INIT_LIST_HEAD(&sdbg_host->dev_info_list);
+
+	devs_per_host = sdebug_num_tgts * sdebug_max_luns;
+	for (k = 0; k < devs_per_host; k++) {
+		sdbg_devinfo = sdebug_device_create(sdbg_host, GFP_KERNEL);
+		if (!sdbg_devinfo) {
+			pr_err("out of memory at line %d\n", __LINE__);
+			error = -ENOMEM;
+			goto clean;
+		}
+	}
+
+	spin_lock(&sdebug_host_list_lock);
+	list_add_tail(&sdbg_host->host_list, &sdebug_host_list);
+	spin_unlock(&sdebug_host_list_lock);
+
+	sdbg_host->dev.bus = &pseudo_lld_bus;
+	sdbg_host->dev.parent = pseudo_primary;
+	sdbg_host->dev.release = &sdebug_release_adapter;
+	dev_set_name(&sdbg_host->dev, "adapter%d", sdebug_add_host);
+
+	error = device_register(&sdbg_host->dev);
+
+	if (error)
+		goto clean;
+
+	++sdebug_add_host;
+	return error;
+
+clean:
+	list_for_each_entry_safe(sdbg_devinfo, tmp, &sdbg_host->dev_info_list,
+				 dev_list) {
+		list_del(&sdbg_devinfo->dev_list);
+		kfree(sdbg_devinfo);
+	}
+
+	kfree(sdbg_host);
+	return error;
+}
+
+static void sdebug_remove_adapter(void)
+{
+	struct sdebug_host_info *sdbg_host = NULL;
+
+	spin_lock(&sdebug_host_list_lock);
+	if (!list_empty(&sdebug_host_list)) {
+		sdbg_host = list_entry(sdebug_host_list.prev,
+				       struct sdebug_host_info, host_list);
+		list_del(&sdbg_host->host_list);
+	}
+	spin_unlock(&sdebug_host_list_lock);
+
+	if (!sdbg_host)
+		return;
+
+	device_unregister(&sdbg_host->dev);
+	--sdebug_add_host;
+}
+
+static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth)
+{
+	int num_in_q = 0;
+	struct sdebug_dev_info *devip;
+
+	block_unblock_all_queues(true);
+	devip = (struct sdebug_dev_info *)sdev->hostdata;
+	if (NULL == devip) {
+		block_unblock_all_queues(false);
+		return	-ENODEV;
+	}
+	num_in_q = atomic_read(&devip->num_in_q);
+
+	if (qdepth < 1)
+		qdepth = 1;
+	/* allow to exceed max host qc_arr elements for testing */
+	if (qdepth > SDEBUG_CANQUEUE + 10)
+		qdepth = SDEBUG_CANQUEUE + 10;
+	scsi_change_queue_depth(sdev, qdepth);
+
+	if (SDEBUG_OPT_Q_NOISE & sdebug_opts) {
+		sdev_printk(KERN_INFO, sdev, "%s: qdepth=%d, num_in_q=%d\n",
+			    __func__, qdepth, num_in_q);
+	}
+	block_unblock_all_queues(false);
+	return sdev->queue_depth;
+}
+
+static bool fake_timeout(struct scsi_cmnd *scp)
+{
+	if (0 == (atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth))) {
+		if (sdebug_every_nth < -1)
+			sdebug_every_nth = -1;
+		if (SDEBUG_OPT_TIMEOUT & sdebug_opts)
+			return true; /* ignore command causing timeout */
+		else if (SDEBUG_OPT_MAC_TIMEOUT & sdebug_opts &&
+			 scsi_medium_access_command(scp))
+			return true; /* time out reads and writes */
+	}
+	return false;
+}
+
+static bool fake_host_busy(struct scsi_cmnd *scp)
+{
+	return (sdebug_opts & SDEBUG_OPT_HOST_BUSY) &&
+		(atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) == 0;
+}
+
+static int scsi_debug_queuecommand(struct Scsi_Host *shost,
+				   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 (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *) = NULL;
+	int k, na;
+	int errsts = 0;
+	u32 flags;
+	u16 sa;
+	u8 opcode = cmd[0];
+	bool has_wlun_rl;
+
+	scsi_set_resid(scp, 0);
+	if (sdebug_statistics)
+		atomic_inc(&sdebug_cmnd_count);
+	if (unlikely(sdebug_verbose &&
+		     !(SDEBUG_OPT_NO_CDB_NOISE & sdebug_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: tag=%#x, cmd %s\n", my_name,
+			    blk_mq_unique_tag(scp->request), b);
+	}
+	if (fake_host_busy(scp))
+		return SCSI_MLQUEUE_HOST_BUSY;
+	has_wlun_rl = (sdp->lun == SCSI_W_LUN_REPORT_LUNS);
+	if (unlikely((sdp->lun >= sdebug_max_luns) && !has_wlun_rl))
+		goto err_out;
+
+	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 (unlikely(!devip)) {
+		devip = find_build_dev_info(sdp);
+		if (NULL == devip)
+			goto err_out;
+	}
+	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 (unlikely(F_INV_OP & flags)) {
+		mk_sense_invalid_opcode(scp);
+		goto check_cond;
+	}
+	if (unlikely(has_wlun_rl && !(F_RL_WLUN_OK & flags))) {
+		if (sdebug_verbose)
+			sdev_printk(KERN_INFO, sdp, "%s: Opcode 0x%x not%s\n",
+				    my_name, opcode, " supported for wlun");
+		mk_sense_invalid_opcode(scp);
+		goto check_cond;
+	}
+	if (unlikely(sdebug_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 (unlikely(!(F_SKIP_UA & flags) &&
+		     find_first_bit(devip->uas_bm,
+				    SDEBUG_NUM_UAS) != SDEBUG_NUM_UAS)) {
+		errsts = make_ua(scp, devip);
+		if (errsts)
+			goto check_cond;
+	}
+	if (unlikely((F_M_ACCESS & flags) && atomic_read(&devip->stopped))) {
+		mk_sense_buffer(scp, NOT_READY, LOGICAL_UNIT_NOT_READY, 0x2);
+		if (sdebug_verbose)
+			sdev_printk(KERN_INFO, sdp, "%s reports: Not ready: "
+				    "%s\n", my_name, "initializing command "
+				    "required");
+		errsts = check_condition_result;
+		goto fini;
+	}
+	if (sdebug_fake_rw && (F_FAKE_RW & flags))
+		goto fini;
+	if (unlikely(sdebug_every_nth)) {
+		if (fake_timeout(scp))
+			return 0;	/* ignore command: make trouble */
+	}
+	if (likely(oip->pfp))
+		pfp = oip->pfp;	/* calls a resp_* function */
+	else
+		pfp = r_pfp;    /* if leaf function ptr NULL, try the root's */
+
+fini:
+	if (F_DELAY_OVERR & flags)
+		return schedule_resp(scp, devip, errsts, pfp, 0, 0);
+	else if ((flags & F_LONG_DELAY) && (sdebug_jdelay > 0 ||
+					    sdebug_ndelay > 10000)) {
+		/*
+		 * Skip long delays if ndelay <= 10 microseconds. Otherwise
+		 * for Start Stop Unit (SSU) want at least 1 second delay and
+		 * if sdebug_jdelay>1 want a long delay of that many seconds.
+		 * For Synchronize Cache want 1/20 of SSU's delay.
+		 */
+		int jdelay = (sdebug_jdelay < 2) ? 1 : sdebug_jdelay;
+		int denom = (flags & F_SYNC_DELAY) ? 20 : 1;
+
+		jdelay = mult_frac(USER_HZ * jdelay, HZ, denom * USER_HZ);
+		return schedule_resp(scp, devip, errsts, pfp, jdelay, 0);
+	} else
+		return schedule_resp(scp, devip, errsts, pfp, sdebug_jdelay,
+				     sdebug_ndelay);
+check_cond:
+	return schedule_resp(scp, devip, check_condition_result, NULL, 0, 0);
+err_out:
+	return schedule_resp(scp, NULL, DID_NO_CONNECT << 16, NULL, 0, 0);
+}
+
+static struct scsi_host_template sdebug_driver_template = {
+	.show_info =		scsi_debug_show_info,
+	.write_info =		scsi_debug_write_info,
+	.proc_name =		sdebug_proc_name,
+	.name =			"SCSI DEBUG",
+	.info =			scsi_debug_info,
+	.slave_alloc =		scsi_debug_slave_alloc,
+	.slave_configure =	scsi_debug_slave_configure,
+	.slave_destroy =	scsi_debug_slave_destroy,
+	.ioctl =		scsi_debug_ioctl,
+	.queuecommand =		scsi_debug_queuecommand,
+	.change_queue_depth =	sdebug_change_qdepth,
+	.eh_abort_handler =	scsi_debug_abort,
+	.eh_device_reset_handler = scsi_debug_device_reset,
+	.eh_target_reset_handler = scsi_debug_target_reset,
+	.eh_bus_reset_handler = scsi_debug_bus_reset,
+	.eh_host_reset_handler = scsi_debug_host_reset,
+	.can_queue =		SDEBUG_CANQUEUE,
+	.this_id =		7,
+	.sg_tablesize =		SG_MAX_SEGMENTS,
+	.cmd_per_lun =		DEF_CMD_PER_LUN,
+	.max_sectors =		-1U,
+	.use_clustering = 	DISABLE_CLUSTERING,
+	.module =		THIS_MODULE,
+	.track_queue_depth =	1,
+};
+
+static int sdebug_driver_probe(struct device *dev)
+{
+	int error = 0;
+	struct sdebug_host_info *sdbg_host;
+	struct Scsi_Host *hpnt;
+	int hprot;
+
+	sdbg_host = to_sdebug_host(dev);
+
+	sdebug_driver_template.can_queue = sdebug_max_queue;
+	if (sdebug_clustering)
+		sdebug_driver_template.use_clustering = ENABLE_CLUSTERING;
+	hpnt = scsi_host_alloc(&sdebug_driver_template, sizeof(sdbg_host));
+	if (NULL == hpnt) {
+		pr_err("scsi_host_alloc failed\n");
+		error = -ENODEV;
+		return error;
+	}
+	if (submit_queues > nr_cpu_ids) {
+		pr_warn("%s: trim submit_queues (was %d) to nr_cpu_ids=%u\n",
+			my_name, submit_queues, nr_cpu_ids);
+		submit_queues = nr_cpu_ids;
+	}
+	/* Decide whether to tell scsi subsystem that we want mq */
+	/* Following should give the same answer for each host */
+	if (shost_use_blk_mq(hpnt))
+		hpnt->nr_hw_queues = submit_queues;
+
+	sdbg_host->shost = hpnt;
+	*((struct sdebug_host_info **)hpnt->hostdata) = sdbg_host;
+	if ((hpnt->this_id >= 0) && (sdebug_num_tgts > hpnt->this_id))
+		hpnt->max_id = sdebug_num_tgts + 1;
+	else
+		hpnt->max_id = sdebug_num_tgts;
+	/* = sdebug_max_luns; */
+	hpnt->max_lun = SCSI_W_LUN_REPORT_LUNS + 1;
+
+	hprot = 0;
+
+	switch (sdebug_dif) {
+
+	case T10_PI_TYPE1_PROTECTION:
+		hprot = SHOST_DIF_TYPE1_PROTECTION;
+		if (sdebug_dix)
+			hprot |= SHOST_DIX_TYPE1_PROTECTION;
+		break;
+
+	case T10_PI_TYPE2_PROTECTION:
+		hprot = SHOST_DIF_TYPE2_PROTECTION;
+		if (sdebug_dix)
+			hprot |= SHOST_DIX_TYPE2_PROTECTION;
+		break;
+
+	case T10_PI_TYPE3_PROTECTION:
+		hprot = SHOST_DIF_TYPE3_PROTECTION;
+		if (sdebug_dix)
+			hprot |= SHOST_DIX_TYPE3_PROTECTION;
+		break;
+
+	default:
+		if (sdebug_dix)
+			hprot |= SHOST_DIX_TYPE0_PROTECTION;
+		break;
+	}
+
+	scsi_host_set_prot(hpnt, hprot);
+
+	if (have_dif_prot || sdebug_dix)
+		pr_info("host protection%s%s%s%s%s%s%s\n",
+			(hprot & SHOST_DIF_TYPE1_PROTECTION) ? " DIF1" : "",
+			(hprot & SHOST_DIF_TYPE2_PROTECTION) ? " DIF2" : "",
+			(hprot & SHOST_DIF_TYPE3_PROTECTION) ? " DIF3" : "",
+			(hprot & SHOST_DIX_TYPE0_PROTECTION) ? " DIX0" : "",
+			(hprot & SHOST_DIX_TYPE1_PROTECTION) ? " DIX1" : "",
+			(hprot & SHOST_DIX_TYPE2_PROTECTION) ? " DIX2" : "",
+			(hprot & SHOST_DIX_TYPE3_PROTECTION) ? " DIX3" : "");
+
+	if (sdebug_guard == 1)
+		scsi_host_set_guard(hpnt, SHOST_DIX_GUARD_IP);
+	else
+		scsi_host_set_guard(hpnt, SHOST_DIX_GUARD_CRC);
+
+	sdebug_verbose = !!(SDEBUG_OPT_NOISE & sdebug_opts);
+	sdebug_any_injecting_opt = !!(SDEBUG_OPT_ALL_INJECTING & sdebug_opts);
+	if (sdebug_every_nth)	/* need stats counters for every_nth */
+		sdebug_statistics = true;
+	error = scsi_add_host(hpnt, &sdbg_host->dev);
+	if (error) {
+		pr_err("scsi_add_host failed\n");
+		error = -ENODEV;
+		scsi_host_put(hpnt);
+	} else
+		scsi_scan_host(hpnt);
+
+	return error;
+}
+
+static int sdebug_driver_remove(struct device *dev)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct sdebug_dev_info *sdbg_devinfo, *tmp;
+
+	sdbg_host = to_sdebug_host(dev);
+
+	if (!sdbg_host) {
+		pr_err("Unable to locate host info\n");
+		return -ENODEV;
+	}
+
+	scsi_remove_host(sdbg_host->shost);
+
+	list_for_each_entry_safe(sdbg_devinfo, tmp, &sdbg_host->dev_info_list,
+				 dev_list) {
+		list_del(&sdbg_devinfo->dev_list);
+		kfree(sdbg_devinfo);
+	}
+
+	scsi_host_put(sdbg_host->shost);
+	return 0;
+}
+
+static int pseudo_lld_bus_match(struct device *dev,
+				struct device_driver *dev_driver)
+{
+	return 1;
+}
+
+static struct bus_type pseudo_lld_bus = {
+	.name = "pseudo",
+	.match = pseudo_lld_bus_match,
+	.probe = sdebug_driver_probe,
+	.remove = sdebug_driver_remove,
+	.drv_groups = sdebug_drv_groups,
+};