1 files changed, 563 insertions, 5 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 9c0af50501..6d8218a441 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -41,6 +41,8 @@
 #include <linux/random.h>
 #include <linux/xarray.h>
 #include <linux/prefetch.h>
+#include <linux/debugfs.h>
+#include <linux/async.h>
 
 #include <net/checksum.h>
 
@@ -285,6 +287,46 @@ struct sdeb_zone_state {	/* ZBC: per zone state */
 	sector_t z_wp;
 };
 
+enum sdebug_err_type {
+	ERR_TMOUT_CMD		= 0,	/* make specific scsi command timeout */
+	ERR_FAIL_QUEUE_CMD	= 1,	/* make specific scsi command's */
+					/* queuecmd return failed */
+	ERR_FAIL_CMD		= 2,	/* make specific scsi command's */
+					/* queuecmd return succeed but */
+					/* with errors set in scsi_cmnd */
+	ERR_ABORT_CMD_FAILED	= 3,	/* control return FAILED from */
+					/* scsi_debug_abort() */
+	ERR_LUN_RESET_FAILED	= 4,	/* control return FAILED from */
+					/* scsi_debug_device_reseLUN_RESET_FAILEDt() */
+};
+
+struct sdebug_err_inject {
+	int type;
+	struct list_head list;
+	int cnt;
+	unsigned char cmd;
+	struct rcu_head rcu;
+
+	union {
+		/*
+		 * For ERR_FAIL_QUEUE_CMD
+		 */
+		int queuecmd_ret;
+
+		/*
+		 * For ERR_FAIL_CMD
+		 */
+		struct {
+			unsigned char host_byte;
+			unsigned char driver_byte;
+			unsigned char status_byte;
+			unsigned char sense_key;
+			unsigned char asc;
+			unsigned char asq;
+		};
+	};
+};
+
 struct sdebug_dev_info {
 	struct list_head dev_list;
 	unsigned int channel;
@@ -310,6 +352,15 @@ struct sdebug_dev_info {
 	unsigned int max_open;
 	ktime_t create_ts;	/* time since bootup that this device was created */
 	struct sdeb_zone_state *zstate;
+
+	struct dentry *debugfs_entry;
+	struct spinlock list_lock;
+	struct list_head inject_err_list;
+};
+
+struct sdebug_target_info {
+	bool reset_fail;
+	struct dentry *debugfs_entry;
 };
 
 struct sdebug_host_info {
@@ -792,6 +843,7 @@ static bool have_dif_prot;
 static bool write_since_sync;
 static bool sdebug_statistics = DEF_STATISTICS;
 static bool sdebug_wp;
+static bool sdebug_allow_restart;
 /* Following enum: 0: no zbc, def; 1: host aware; 2: host managed */
 static enum blk_zoned_model sdeb_zbc_model = BLK_ZONED_NONE;
 static char *sdeb_zbc_model_s;
@@ -862,6 +914,258 @@ static const int device_qfull_result =
 
 static const int condition_met_result = SAM_STAT_CONDITION_MET;
 
+static struct dentry *sdebug_debugfs_root;
+
+static void sdebug_err_free(struct rcu_head *head)
+{
+	struct sdebug_err_inject *inject =
+		container_of(head, typeof(*inject), rcu);
+
+	kfree(inject);
+}
+
+static void sdebug_err_add(struct scsi_device *sdev, struct sdebug_err_inject *new)
+{
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdev->hostdata;
+	struct sdebug_err_inject *err;
+
+	spin_lock(&devip->list_lock);
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == new->type && err->cmd == new->cmd) {
+			list_del_rcu(&err->list);
+			call_rcu(&err->rcu, sdebug_err_free);
+		}
+	}
+
+	list_add_tail_rcu(&new->list, &devip->inject_err_list);
+	spin_unlock(&devip->list_lock);
+}
+
+static int sdebug_err_remove(struct scsi_device *sdev, const char *buf, size_t count)
+{
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdev->hostdata;
+	struct sdebug_err_inject *err;
+	int type;
+	unsigned char cmd;
+
+	if (sscanf(buf, "- %d %hhx", &type, &cmd) != 2) {
+		kfree(buf);
+		return -EINVAL;
+	}
+
+	spin_lock(&devip->list_lock);
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == type && err->cmd == cmd) {
+			list_del_rcu(&err->list);
+			call_rcu(&err->rcu, sdebug_err_free);
+			spin_unlock(&devip->list_lock);
+			kfree(buf);
+			return count;
+		}
+	}
+	spin_unlock(&devip->list_lock);
+
+	kfree(buf);
+	return -EINVAL;
+}
+
+static int sdebug_error_show(struct seq_file *m, void *p)
+{
+	struct scsi_device *sdev = (struct scsi_device *)m->private;
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdev->hostdata;
+	struct sdebug_err_inject *err;
+
+	seq_puts(m, "Type\tCount\tCommand\n");
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		switch (err->type) {
+		case ERR_TMOUT_CMD:
+		case ERR_ABORT_CMD_FAILED:
+		case ERR_LUN_RESET_FAILED:
+			seq_printf(m, "%d\t%d\t0x%x\n", err->type, err->cnt,
+				err->cmd);
+		break;
+
+		case ERR_FAIL_QUEUE_CMD:
+			seq_printf(m, "%d\t%d\t0x%x\t0x%x\n", err->type,
+				err->cnt, err->cmd, err->queuecmd_ret);
+		break;
+
+		case ERR_FAIL_CMD:
+			seq_printf(m, "%d\t%d\t0x%x\t0x%x 0x%x 0x%x 0x%x 0x%x 0x%x\n",
+				err->type, err->cnt, err->cmd,
+				err->host_byte, err->driver_byte,
+				err->status_byte, err->sense_key,
+				err->asc, err->asq);
+		break;
+		}
+	}
+	rcu_read_unlock();
+
+	return 0;
+}
+
+static int sdebug_error_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, sdebug_error_show, inode->i_private);
+}
+
+static ssize_t sdebug_error_write(struct file *file, const char __user *ubuf,
+		size_t count, loff_t *ppos)
+{
+	char *buf;
+	unsigned int inject_type;
+	struct sdebug_err_inject *inject;
+	struct scsi_device *sdev = (struct scsi_device *)file->f_inode->i_private;
+
+	buf = kzalloc(count + 1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (copy_from_user(buf, ubuf, count)) {
+		kfree(buf);
+		return -EFAULT;
+	}
+
+	if (buf[0] == '-')
+		return sdebug_err_remove(sdev, buf, count);
+
+	if (sscanf(buf, "%d", &inject_type) != 1) {
+		kfree(buf);
+		return -EINVAL;
+	}
+
+	inject = kzalloc(sizeof(struct sdebug_err_inject), GFP_KERNEL);
+	if (!inject) {
+		kfree(buf);
+		return -ENOMEM;
+	}
+
+	switch (inject_type) {
+	case ERR_TMOUT_CMD:
+	case ERR_ABORT_CMD_FAILED:
+	case ERR_LUN_RESET_FAILED:
+		if (sscanf(buf, "%d %d %hhx", &inject->type, &inject->cnt,
+			   &inject->cmd) != 3)
+			goto out_error;
+	break;
+
+	case ERR_FAIL_QUEUE_CMD:
+		if (sscanf(buf, "%d %d %hhx %x", &inject->type, &inject->cnt,
+			   &inject->cmd, &inject->queuecmd_ret) != 4)
+			goto out_error;
+	break;
+
+	case ERR_FAIL_CMD:
+		if (sscanf(buf, "%d %d %hhx %hhx %hhx %hhx %hhx %hhx %hhx",
+			   &inject->type, &inject->cnt, &inject->cmd,
+			   &inject->host_byte, &inject->driver_byte,
+			   &inject->status_byte, &inject->sense_key,
+			   &inject->asc, &inject->asq) != 9)
+			goto out_error;
+	break;
+
+	default:
+		goto out_error;
+	break;
+	}
+
+	kfree(buf);
+	sdebug_err_add(sdev, inject);
+
+	return count;
+
+out_error:
+	kfree(buf);
+	kfree(inject);
+	return -EINVAL;
+}
+
+static const struct file_operations sdebug_error_fops = {
+	.open	= sdebug_error_open,
+	.read	= seq_read,
+	.write	= sdebug_error_write,
+	.release = single_release,
+};
+
+static int sdebug_target_reset_fail_show(struct seq_file *m, void *p)
+{
+	struct scsi_target *starget = (struct scsi_target *)m->private;
+	struct sdebug_target_info *targetip =
+		(struct sdebug_target_info *)starget->hostdata;
+
+	if (targetip)
+		seq_printf(m, "%c\n", targetip->reset_fail ? 'Y' : 'N');
+
+	return 0;
+}
+
+static int sdebug_target_reset_fail_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, sdebug_target_reset_fail_show, inode->i_private);
+}
+
+static ssize_t sdebug_target_reset_fail_write(struct file *file,
+		const char __user *ubuf, size_t count, loff_t *ppos)
+{
+	int ret;
+	struct scsi_target *starget =
+		(struct scsi_target *)file->f_inode->i_private;
+	struct sdebug_target_info *targetip =
+		(struct sdebug_target_info *)starget->hostdata;
+
+	if (targetip) {
+		ret = kstrtobool_from_user(ubuf, count, &targetip->reset_fail);
+		return ret < 0 ? ret : count;
+	}
+	return -ENODEV;
+}
+
+static const struct file_operations sdebug_target_reset_fail_fops = {
+	.open	= sdebug_target_reset_fail_open,
+	.read	= seq_read,
+	.write	= sdebug_target_reset_fail_write,
+	.release = single_release,
+};
+
+static int sdebug_target_alloc(struct scsi_target *starget)
+{
+	struct sdebug_target_info *targetip;
+
+	targetip = kzalloc(sizeof(struct sdebug_target_info), GFP_KERNEL);
+	if (!targetip)
+		return -ENOMEM;
+
+	targetip->debugfs_entry = debugfs_create_dir(dev_name(&starget->dev),
+				sdebug_debugfs_root);
+
+	debugfs_create_file("fail_reset", 0600, targetip->debugfs_entry, starget,
+				&sdebug_target_reset_fail_fops);
+
+	starget->hostdata = targetip;
+
+	return 0;
+}
+
+static void sdebug_tartget_cleanup_async(void *data, async_cookie_t cookie)
+{
+	struct sdebug_target_info *targetip = data;
+
+	debugfs_remove(targetip->debugfs_entry);
+	kfree(targetip);
+}
+
+static void sdebug_target_destroy(struct scsi_target *starget)
+{
+	struct sdebug_target_info *targetip;
+
+	targetip = (struct sdebug_target_info *)starget->hostdata;
+	if (targetip) {
+		starget->hostdata = NULL;
+		async_schedule(sdebug_tartget_cleanup_async, targetip);
+	}
+}
 
 /* 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
@@ -5096,6 +5400,8 @@ static struct sdebug_dev_info *sdebug_device_create(
 		}
 		devip->create_ts = ktime_get_boottime();
 		atomic_set(&devip->stopped, (sdeb_tur_ms_to_ready > 0 ? 2 : 0));
+		spin_lock_init(&devip->list_lock);
+		INIT_LIST_HEAD(&devip->inject_err_list);
 		list_add_tail(&devip->dev_list, &sdbg_host->dev_info_list);
 	}
 	return devip;
@@ -5141,6 +5447,7 @@ 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);
+
 	return 0;
 }
 
@@ -5148,6 +5455,7 @@ static int scsi_debug_slave_configure(struct scsi_device *sdp)
 {
 	struct sdebug_dev_info *devip =
 			(struct sdebug_dev_info *)sdp->hostdata;
+	struct dentry *dentry;
 
 	if (sdebug_verbose)
 		pr_info("slave_configure <%u %u %u %llu>\n",
@@ -5163,6 +5471,22 @@ static int scsi_debug_slave_configure(struct scsi_device *sdp)
 	if (sdebug_no_uld)
 		sdp->no_uld_attach = 1;
 	config_cdb_len(sdp);
+
+	if (sdebug_allow_restart)
+		sdp->allow_restart = 1;
+
+	devip->debugfs_entry = debugfs_create_dir(dev_name(&sdp->sdev_dev),
+				sdebug_debugfs_root);
+	if (IS_ERR_OR_NULL(devip->debugfs_entry))
+		pr_info("%s: failed to create debugfs directory for device %s\n",
+			__func__, dev_name(&sdp->sdev_gendev));
+
+	dentry = debugfs_create_file("error", 0600, devip->debugfs_entry, sdp,
+				&sdebug_error_fops);
+	if (IS_ERR_OR_NULL(dentry))
+		pr_info("%s: failed to create error file for device %s\n",
+			__func__, dev_name(&sdp->sdev_gendev));
+
 	return 0;
 }
 
@@ -5170,15 +5494,27 @@ static void scsi_debug_slave_destroy(struct scsi_device *sdp)
 {
 	struct sdebug_dev_info *devip =
 		(struct sdebug_dev_info *)sdp->hostdata;
+	struct sdebug_err_inject *err;
 
 	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;
+
+	if (!devip)
+		return;
+
+	spin_lock(&devip->list_lock);
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		list_del_rcu(&err->list);
+		call_rcu(&err->rcu, sdebug_err_free);
 	}
+	spin_unlock(&devip->list_lock);
+
+	debugfs_remove(devip->debugfs_entry);
+
+	/* make this slot available for re-use */
+	devip->used = false;
+	sdp->hostdata = NULL;
 }
 
 /* Returns true if we require the queued memory to be freed by the caller. */
@@ -5272,9 +5608,39 @@ static void stop_all_queued(void)
 	mutex_unlock(&sdebug_host_list_mutex);
 }
 
+static int sdebug_fail_abort(struct scsi_cmnd *cmnd)
+{
+	struct scsi_device *sdp = cmnd->device;
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+	struct sdebug_err_inject *err;
+	unsigned char *cmd = cmnd->cmnd;
+	int ret = 0;
+
+	if (devip == NULL)
+		return 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == ERR_ABORT_CMD_FAILED &&
+		    (err->cmd == cmd[0] || err->cmd == 0xff)) {
+			ret = !!err->cnt;
+			if (err->cnt < 0)
+				err->cnt++;
+
+			rcu_read_unlock();
+			return ret;
+		}
+	}
+	rcu_read_unlock();
+
+	return 0;
+}
+
 static int scsi_debug_abort(struct scsi_cmnd *SCpnt)
 {
 	bool ok = scsi_debug_abort_cmnd(SCpnt);
+	u8 *cmd = SCpnt->cmnd;
+	u8 opcode = cmd[0];
 
 	++num_aborts;
 
@@ -5283,6 +5649,12 @@ static int scsi_debug_abort(struct scsi_cmnd *SCpnt)
 			    "%s: command%s found\n", __func__,
 			    ok ? "" : " not");
 
+	if (sdebug_fail_abort(SCpnt)) {
+		scmd_printk(KERN_INFO, SCpnt, "fail abort command 0x%x\n",
+			    opcode);
+		return FAILED;
+	}
+
 	return SUCCESS;
 }
 
@@ -5306,10 +5678,40 @@ static void scsi_debug_stop_all_queued(struct scsi_device *sdp)
 				scsi_debug_stop_all_queued_iter, sdp);
 }
 
+static int sdebug_fail_lun_reset(struct scsi_cmnd *cmnd)
+{
+	struct scsi_device *sdp = cmnd->device;
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+	struct sdebug_err_inject *err;
+	unsigned char *cmd = cmnd->cmnd;
+	int ret = 0;
+
+	if (devip == NULL)
+		return 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == ERR_LUN_RESET_FAILED &&
+		    (err->cmd == cmd[0] || err->cmd == 0xff)) {
+			ret = !!err->cnt;
+			if (err->cnt < 0)
+				err->cnt++;
+
+			rcu_read_unlock();
+			return ret;
+		}
+	}
+	rcu_read_unlock();
+
+	return 0;
+}
+
 static int scsi_debug_device_reset(struct scsi_cmnd *SCpnt)
 {
 	struct scsi_device *sdp = SCpnt->device;
 	struct sdebug_dev_info *devip = sdp->hostdata;
+	u8 *cmd = SCpnt->cmnd;
+	u8 opcode = cmd[0];
 
 	++num_dev_resets;
 
@@ -5320,14 +5722,33 @@ static int scsi_debug_device_reset(struct scsi_cmnd *SCpnt)
 	if (devip)
 		set_bit(SDEBUG_UA_POR, devip->uas_bm);
 
+	if (sdebug_fail_lun_reset(SCpnt)) {
+		scmd_printk(KERN_INFO, SCpnt, "fail lun reset 0x%x\n", opcode);
+		return FAILED;
+	}
+
 	return SUCCESS;
 }
 
+static int sdebug_fail_target_reset(struct scsi_cmnd *cmnd)
+{
+	struct scsi_target *starget = scsi_target(cmnd->device);
+	struct sdebug_target_info *targetip =
+		(struct sdebug_target_info *)starget->hostdata;
+
+	if (targetip)
+		return targetip->reset_fail;
+
+	return 0;
+}
+
 static int scsi_debug_target_reset(struct scsi_cmnd *SCpnt)
 {
 	struct scsi_device *sdp = SCpnt->device;
 	struct sdebug_host_info *sdbg_host = shost_to_sdebug_host(sdp->host);
 	struct sdebug_dev_info *devip;
+	u8 *cmd = SCpnt->cmnd;
+	u8 opcode = cmd[0];
 	int k = 0;
 
 	++num_target_resets;
@@ -5345,6 +5766,12 @@ static int scsi_debug_target_reset(struct scsi_cmnd *SCpnt)
 		sdev_printk(KERN_INFO, sdp,
 			    "%s: %d device(s) found in target\n", __func__, k);
 
+	if (sdebug_fail_target_reset(SCpnt)) {
+		scmd_printk(KERN_INFO, SCpnt, "fail target reset 0x%x\n",
+			    opcode);
+		return FAILED;
+	}
+
 	return SUCCESS;
 }
 
@@ -5772,6 +6199,7 @@ module_param_named(zone_cap_mb, sdeb_zbc_zone_cap_mb, int, S_IRUGO);
 module_param_named(zone_max_open, sdeb_zbc_max_open, int, S_IRUGO);
 module_param_named(zone_nr_conv, sdeb_zbc_nr_conv, int, S_IRUGO);
 module_param_named(zone_size_mb, sdeb_zbc_zone_size_mb, int, S_IRUGO);
+module_param_named(allow_restart, sdebug_allow_restart, bool, S_IRUGO | S_IWUSR);
 
 MODULE_AUTHOR("Eric Youngdale + Douglas Gilbert");
 MODULE_DESCRIPTION("SCSI debug adapter driver");
@@ -5844,6 +6272,7 @@ MODULE_PARM_DESC(zone_cap_mb, "Zone capacity in MiB (def=zone size)");
 MODULE_PARM_DESC(zone_max_open, "Maximum number of open zones; [0] for no limit (def=auto)");
 MODULE_PARM_DESC(zone_nr_conv, "Number of conventional zones (def=1)");
 MODULE_PARM_DESC(zone_size_mb, "Zone size in MiB (def=auto)");
+MODULE_PARM_DESC(allow_restart, "Set scsi_device's allow_restart flag(def=0)");
 
 #define SDEBUG_INFO_LEN 256
 static char sdebug_info[SDEBUG_INFO_LEN];
@@ -7011,6 +7440,10 @@ static int __init scsi_debug_init(void)
 		goto driver_unreg;
 	}
 
+	sdebug_debugfs_root = debugfs_create_dir("scsi_debug", NULL);
+	if (IS_ERR_OR_NULL(sdebug_debugfs_root))
+		pr_info("%s: failed to create initial debugfs directory\n", __func__);
+
 	for (k = 0; k < hosts_to_add; k++) {
 		if (want_store && k == 0) {
 			ret = sdebug_add_host_helper(idx);
@@ -7057,6 +7490,7 @@ static void __exit scsi_debug_exit(void)
 
 	sdebug_erase_all_stores(false);
 	xa_destroy(per_store_ap);
+	debugfs_remove(sdebug_debugfs_root);
 }
 
 device_initcall(scsi_debug_init);
@@ -7496,6 +7930,104 @@ static int sdebug_blk_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
 	return num_entries;
 }
 
+static int sdebug_timeout_cmd(struct scsi_cmnd *cmnd)
+{
+	struct scsi_device *sdp = cmnd->device;
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+	struct sdebug_err_inject *err;
+	unsigned char *cmd = cmnd->cmnd;
+	int ret = 0;
+
+	if (devip == NULL)
+		return 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == ERR_TMOUT_CMD &&
+		    (err->cmd == cmd[0] || err->cmd == 0xff)) {
+			ret = !!err->cnt;
+			if (err->cnt < 0)
+				err->cnt++;
+
+			rcu_read_unlock();
+			return ret;
+		}
+	}
+	rcu_read_unlock();
+
+	return 0;
+}
+
+static int sdebug_fail_queue_cmd(struct scsi_cmnd *cmnd)
+{
+	struct scsi_device *sdp = cmnd->device;
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+	struct sdebug_err_inject *err;
+	unsigned char *cmd = cmnd->cmnd;
+	int ret = 0;
+
+	if (devip == NULL)
+		return 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == ERR_FAIL_QUEUE_CMD &&
+		    (err->cmd == cmd[0] || err->cmd == 0xff)) {
+			ret = err->cnt ? err->queuecmd_ret : 0;
+			if (err->cnt < 0)
+				err->cnt++;
+
+			rcu_read_unlock();
+			return ret;
+		}
+	}
+	rcu_read_unlock();
+
+	return 0;
+}
+
+static int sdebug_fail_cmd(struct scsi_cmnd *cmnd, int *retval,
+			   struct sdebug_err_inject *info)
+{
+	struct scsi_device *sdp = cmnd->device;
+	struct sdebug_dev_info *devip = (struct sdebug_dev_info *)sdp->hostdata;
+	struct sdebug_err_inject *err;
+	unsigned char *cmd = cmnd->cmnd;
+	int ret = 0;
+	int result;
+
+	if (devip == NULL)
+		return 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(err, &devip->inject_err_list, list) {
+		if (err->type == ERR_FAIL_CMD &&
+		    (err->cmd == cmd[0] || err->cmd == 0xff)) {
+			if (!err->cnt) {
+				rcu_read_unlock();
+				return 0;
+			}
+
+			ret = !!err->cnt;
+			rcu_read_unlock();
+			goto out_handle;
+		}
+	}
+	rcu_read_unlock();
+
+	return 0;
+
+out_handle:
+	if (err->cnt < 0)
+		err->cnt++;
+	mk_sense_buffer(cmnd, err->sense_key, err->asc, err->asq);
+	result = err->status_byte | err->host_byte << 16 | err->driver_byte << 24;
+	*info = *err;
+	*retval = schedule_resp(cmnd, devip, result, NULL, 0, 0);
+
+	return ret;
+}
+
 static int scsi_debug_queuecommand(struct Scsi_Host *shost,
 				   struct scsi_cmnd *scp)
 {
@@ -7515,6 +8047,8 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
 	u8 opcode = cmd[0];
 	bool has_wlun_rl;
 	bool inject_now;
+	int ret = 0;
+	struct sdebug_err_inject err;
 
 	scsi_set_resid(scp, 0);
 	if (sdebug_statistics) {
@@ -7554,6 +8088,29 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
 		if (NULL == devip)
 			goto err_out;
 	}
+
+	if (sdebug_timeout_cmd(scp)) {
+		scmd_printk(KERN_INFO, scp, "timeout command 0x%x\n", opcode);
+		return 0;
+	}
+
+	ret = sdebug_fail_queue_cmd(scp);
+	if (ret) {
+		scmd_printk(KERN_INFO, scp, "fail queue command 0x%x with 0x%x\n",
+				opcode, ret);
+		return ret;
+	}
+
+	if (sdebug_fail_cmd(scp, &ret, &err)) {
+		scmd_printk(KERN_INFO, scp,
+			"fail command 0x%x with hostbyte=0x%x, "
+			"driverbyte=0x%x, statusbyte=0x%x, "
+			"sense_key=0x%x, asc=0x%x, asq=0x%x\n",
+			opcode, err.host_byte, err.driver_byte,
+			err.status_byte, err.sense_key, err.asc, err.asq);
+		return ret;
+	}
+
 	if (unlikely(inject_now && !atomic_read(&sdeb_inject_pending)))
 		atomic_set(&sdeb_inject_pending, 1);
 
@@ -7672,7 +8229,6 @@ static int sdebug_init_cmd_priv(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
 	return 0;
 }
 
-
 static struct scsi_host_template sdebug_driver_template = {
 	.show_info =		scsi_debug_show_info,
 	.write_info =		scsi_debug_write_info,
@@ -7702,6 +8258,8 @@ static struct scsi_host_template sdebug_driver_template = {
 	.track_queue_depth =	1,
 	.cmd_size = sizeof(struct sdebug_scsi_cmd),
 	.init_cmd_priv = sdebug_init_cmd_priv,
+	.target_alloc =		sdebug_target_alloc,
+	.target_destroy =	sdebug_target_destroy,
 };
 
 static int sdebug_driver_probe(struct device *dev)