initial Olimex linux tree from Daniel, originally Feb 3, 2016

1 files changed, 1179 insertions, 0 deletions

diff --git a/linux/drivers/target/target_core_pscsi.c b/linux/drivers/target/target_core_pscsi.c
new file mode 100644
index 00000000..ecc5eaef
--- /dev/null
+++ b/linux/drivers/target/target_core_pscsi.c
@@ -0,0 +1,1179 @@
+/*******************************************************************************
+ * Filename:  target_core_pscsi.c
+ *
+ * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
+ *
+ * (c) Copyright 2003-2013 Datera, Inc.
+ *
+ * Nicholas A. Bellinger <nab@kernel.org>
+ *
+ * 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ ******************************************************************************/
+
+#include <linux/string.h>
+#include <linux/parser.h>
+#include <linux/timer.h>
+#include <linux/blkdev.h>
+#include <linux/blk_types.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/genhd.h>
+#include <linux/cdrom.h>
+#include <linux/ratelimit.h>
+#include <linux/module.h>
+#include <asm/unaligned.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_tcq.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+#include <target/target_core_backend_configfs.h>
+
+#include "target_core_alua.h"
+#include "target_core_pscsi.h"
+
+#define ISPRINT(a)  ((a >= ' ') && (a <= '~'))
+
+static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
+{
+	return container_of(dev, struct pscsi_dev_virt, dev);
+}
+
+static struct se_subsystem_api pscsi_template;
+
+static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
+static void pscsi_req_done(struct request *, int);
+
+/*	pscsi_attach_hba():
+ *
+ * 	pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
+ *	from the passed SCSI Host ID.
+ */
+static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
+{
+	struct pscsi_hba_virt *phv;
+
+	phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
+	if (!phv) {
+		pr_err("Unable to allocate struct pscsi_hba_virt\n");
+		return -ENOMEM;
+	}
+	phv->phv_host_id = host_id;
+	phv->phv_mode = PHV_VIRTUAL_HOST_ID;
+
+	hba->hba_ptr = phv;
+
+	pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
+		" Generic Target Core Stack %s\n", hba->hba_id,
+		PSCSI_VERSION, TARGET_CORE_MOD_VERSION);
+	pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
+	       hba->hba_id);
+
+	return 0;
+}
+
+static void pscsi_detach_hba(struct se_hba *hba)
+{
+	struct pscsi_hba_virt *phv = hba->hba_ptr;
+	struct Scsi_Host *scsi_host = phv->phv_lld_host;
+
+	if (scsi_host) {
+		scsi_host_put(scsi_host);
+
+		pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
+			" Generic Target Core\n", hba->hba_id,
+			(scsi_host->hostt->name) ? (scsi_host->hostt->name) :
+			"Unknown");
+	} else
+		pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
+			" from Generic Target Core\n", hba->hba_id);
+
+	kfree(phv);
+	hba->hba_ptr = NULL;
+}
+
+static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
+{
+	struct pscsi_hba_virt *phv = hba->hba_ptr;
+	struct Scsi_Host *sh = phv->phv_lld_host;
+	/*
+	 * Release the struct Scsi_Host
+	 */
+	if (!mode_flag) {
+		if (!sh)
+			return 0;
+
+		phv->phv_lld_host = NULL;
+		phv->phv_mode = PHV_VIRTUAL_HOST_ID;
+
+		pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
+			" %s\n", hba->hba_id, (sh->hostt->name) ?
+			(sh->hostt->name) : "Unknown");
+
+		scsi_host_put(sh);
+		return 0;
+	}
+	/*
+	 * Otherwise, locate struct Scsi_Host from the original passed
+	 * pSCSI Host ID and enable for phba mode
+	 */
+	sh = scsi_host_lookup(phv->phv_host_id);
+	if (!sh) {
+		pr_err("pSCSI: Unable to locate SCSI Host for"
+			" phv_host_id: %d\n", phv->phv_host_id);
+		return -EINVAL;
+	}
+
+	phv->phv_lld_host = sh;
+	phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
+
+	pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
+		hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
+
+	return 1;
+}
+
+static void pscsi_tape_read_blocksize(struct se_device *dev,
+		struct scsi_device *sdev)
+{
+	unsigned char cdb[MAX_COMMAND_SIZE], *buf;
+	int ret;
+
+	buf = kzalloc(12, GFP_KERNEL);
+	if (!buf)
+		return;
+
+	memset(cdb, 0, MAX_COMMAND_SIZE);
+	cdb[0] = MODE_SENSE;
+	cdb[4] = 0x0c; /* 12 bytes */
+
+	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
+			HZ, 1, NULL);
+	if (ret)
+		goto out_free;
+
+	/*
+	 * If MODE_SENSE still returns zero, set the default value to 1024.
+	 */
+	sdev->sector_size = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
+	if (!sdev->sector_size)
+		sdev->sector_size = 1024;
+out_free:
+	kfree(buf);
+}
+
+static void
+pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
+{
+	unsigned char *buf;
+
+	if (sdev->inquiry_len < INQUIRY_LEN)
+		return;
+
+	buf = sdev->inquiry;
+	if (!buf)
+		return;
+	/*
+	 * Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
+	 */
+	memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
+	memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
+	memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
+}
+
+static int
+pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
+{
+	unsigned char cdb[MAX_COMMAND_SIZE], *buf;
+	int ret;
+
+	buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	memset(cdb, 0, MAX_COMMAND_SIZE);
+	cdb[0] = INQUIRY;
+	cdb[1] = 0x01; /* Query VPD */
+	cdb[2] = 0x80; /* Unit Serial Number */
+	cdb[3] = (INQUIRY_VPD_SERIAL_LEN >> 8) & 0xff;
+	cdb[4] = (INQUIRY_VPD_SERIAL_LEN & 0xff);
+
+	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
+			      INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
+	if (ret)
+		goto out_free;
+
+	snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
+
+	wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
+
+	kfree(buf);
+	return 0;
+
+out_free:
+	kfree(buf);
+	return -EPERM;
+}
+
+static void
+pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
+		struct t10_wwn *wwn)
+{
+	unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
+	int ident_len, page_len, off = 4, ret;
+	struct t10_vpd *vpd;
+
+	buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
+	if (!buf)
+		return;
+
+	memset(cdb, 0, MAX_COMMAND_SIZE);
+	cdb[0] = INQUIRY;
+	cdb[1] = 0x01; /* Query VPD */
+	cdb[2] = 0x83; /* Device Identifier */
+	cdb[3] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN >> 8) & 0xff;
+	cdb[4] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN & 0xff);
+
+	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
+			      INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
+			      NULL, HZ, 1, NULL);
+	if (ret)
+		goto out;
+
+	page_len = (buf[2] << 8) | buf[3];
+	while (page_len > 0) {
+		/* Grab a pointer to the Identification descriptor */
+		page_83 = &buf[off];
+		ident_len = page_83[3];
+		if (!ident_len) {
+			pr_err("page_83[3]: identifier"
+					" length zero!\n");
+			break;
+		}
+		pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
+
+		vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
+		if (!vpd) {
+			pr_err("Unable to allocate memory for"
+					" struct t10_vpd\n");
+			goto out;
+		}
+		INIT_LIST_HEAD(&vpd->vpd_list);
+
+		transport_set_vpd_proto_id(vpd, page_83);
+		transport_set_vpd_assoc(vpd, page_83);
+
+		if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
+			off += (ident_len + 4);
+			page_len -= (ident_len + 4);
+			kfree(vpd);
+			continue;
+		}
+		if (transport_set_vpd_ident(vpd, page_83) < 0) {
+			off += (ident_len + 4);
+			page_len -= (ident_len + 4);
+			kfree(vpd);
+			continue;
+		}
+
+		list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
+		off += (ident_len + 4);
+		page_len -= (ident_len + 4);
+	}
+
+out:
+	kfree(buf);
+}
+
+static int pscsi_add_device_to_list(struct se_device *dev,
+		struct scsi_device *sd)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct request_queue *q = sd->request_queue;
+
+	pdv->pdv_sd = sd;
+
+	if (!sd->queue_depth) {
+		sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
+
+		pr_err("Set broken SCSI Device %d:%d:%llu"
+			" queue_depth to %d\n", sd->channel, sd->id,
+				sd->lun, sd->queue_depth);
+	}
+
+	dev->dev_attrib.hw_block_size = sd->sector_size;
+	dev->dev_attrib.hw_max_sectors =
+		min_t(int, sd->host->max_sectors, queue_max_hw_sectors(q));
+	dev->dev_attrib.hw_queue_depth = sd->queue_depth;
+
+	/*
+	 * Setup our standard INQUIRY info into se_dev->t10_wwn
+	 */
+	pscsi_set_inquiry_info(sd, &dev->t10_wwn);
+
+	/*
+	 * Locate VPD WWN Information used for various purposes within
+	 * the Storage Engine.
+	 */
+	if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
+		/*
+		 * If VPD Unit Serial returned GOOD status, try
+		 * VPD Device Identification page (0x83).
+		 */
+		pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
+	}
+
+	/*
+	 * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
+	 */
+	if (sd->type == TYPE_TAPE)
+		pscsi_tape_read_blocksize(dev, sd);
+	return 0;
+}
+
+static struct se_device *pscsi_alloc_device(struct se_hba *hba,
+		const char *name)
+{
+	struct pscsi_dev_virt *pdv;
+
+	pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
+	if (!pdv) {
+		pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
+		return NULL;
+	}
+
+	pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
+	return &pdv->dev;
+}
+
+/*
+ * Called with struct Scsi_Host->host_lock called.
+ */
+static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
+	__releases(sh->host_lock)
+{
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct Scsi_Host *sh = sd->host;
+	struct block_device *bd;
+	int ret;
+
+	if (scsi_device_get(sd)) {
+		pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
+			sh->host_no, sd->channel, sd->id, sd->lun);
+		spin_unlock_irq(sh->host_lock);
+		return -EIO;
+	}
+	spin_unlock_irq(sh->host_lock);
+	/*
+	 * Claim exclusive struct block_device access to struct scsi_device
+	 * for TYPE_DISK using supplied udev_path
+	 */
+	bd = blkdev_get_by_path(dev->udev_path,
+				FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
+	if (IS_ERR(bd)) {
+		pr_err("pSCSI: blkdev_get_by_path() failed\n");
+		scsi_device_put(sd);
+		return PTR_ERR(bd);
+	}
+	pdv->pdv_bd = bd;
+
+	ret = pscsi_add_device_to_list(dev, sd);
+	if (ret) {
+		blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
+		scsi_device_put(sd);
+		return ret;
+	}
+
+	pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%llu\n",
+		phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
+	return 0;
+}
+
+/*
+ * Called with struct Scsi_Host->host_lock called.
+ */
+static int pscsi_create_type_rom(struct se_device *dev, struct scsi_device *sd)
+	__releases(sh->host_lock)
+{
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	struct Scsi_Host *sh = sd->host;
+	int ret;
+
+	if (scsi_device_get(sd)) {
+		pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
+			sh->host_no, sd->channel, sd->id, sd->lun);
+		spin_unlock_irq(sh->host_lock);
+		return -EIO;
+	}
+	spin_unlock_irq(sh->host_lock);
+
+	ret = pscsi_add_device_to_list(dev, sd);
+	if (ret) {
+		scsi_device_put(sd);
+		return ret;
+	}
+	pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
+		phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
+		sd->channel, sd->id, sd->lun);
+
+	return 0;
+}
+
+/*
+ * Called with struct Scsi_Host->host_lock called.
+ */
+static int pscsi_create_type_other(struct se_device *dev,
+		struct scsi_device *sd)
+	__releases(sh->host_lock)
+{
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	struct Scsi_Host *sh = sd->host;
+	int ret;
+
+	spin_unlock_irq(sh->host_lock);
+	ret = pscsi_add_device_to_list(dev, sd);
+	if (ret)
+		return ret;
+
+	pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
+		phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
+		sd->channel, sd->id, sd->lun);
+	return 0;
+}
+
+static int pscsi_configure_device(struct se_device *dev)
+{
+	struct se_hba *hba = dev->se_hba;
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct scsi_device *sd;
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	struct Scsi_Host *sh = phv->phv_lld_host;
+	int legacy_mode_enable = 0;
+	int ret;
+
+	if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
+	    !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
+	    !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
+		pr_err("Missing scsi_channel_id=, scsi_target_id= and"
+			" scsi_lun_id= parameters\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
+	 * struct Scsi_Host we will need to bring the TCM/pSCSI object online
+	 */
+	if (!sh) {
+		if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
+			pr_err("pSCSI: Unable to locate struct"
+				" Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
+			return -ENODEV;
+		}
+		/*
+		 * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
+		 * reference, we enforce that udev_path has been set
+		 */
+		if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
+			pr_err("pSCSI: udev_path attribute has not"
+				" been set before ENABLE=1\n");
+			return -EINVAL;
+		}
+		/*
+		 * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
+		 * use the original TCM hba ID to reference Linux/SCSI Host No
+		 * and enable for PHV_LLD_SCSI_HOST_NO mode.
+		 */
+		if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
+			if (hba->dev_count) {
+				pr_err("pSCSI: Unable to set hba_mode"
+					" with active devices\n");
+				return -EEXIST;
+			}
+
+			if (pscsi_pmode_enable_hba(hba, 1) != 1)
+				return -ENODEV;
+
+			legacy_mode_enable = 1;
+			hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
+			sh = phv->phv_lld_host;
+		} else {
+			sh = scsi_host_lookup(pdv->pdv_host_id);
+			if (!sh) {
+				pr_err("pSCSI: Unable to locate"
+					" pdv_host_id: %d\n", pdv->pdv_host_id);
+				return -EINVAL;
+			}
+			pdv->pdv_lld_host = sh;
+		}
+	} else {
+		if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
+			pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
+				" struct Scsi_Host exists\n");
+			return -EEXIST;
+		}
+	}
+
+	spin_lock_irq(sh->host_lock);
+	list_for_each_entry(sd, &sh->__devices, siblings) {
+		if ((pdv->pdv_channel_id != sd->channel) ||
+		    (pdv->pdv_target_id != sd->id) ||
+		    (pdv->pdv_lun_id != sd->lun))
+			continue;
+		/*
+		 * Functions will release the held struct scsi_host->host_lock
+		 * before calling calling pscsi_add_device_to_list() to register
+		 * struct scsi_device with target_core_mod.
+		 */
+		switch (sd->type) {
+		case TYPE_DISK:
+			ret = pscsi_create_type_disk(dev, sd);
+			break;
+		case TYPE_ROM:
+			ret = pscsi_create_type_rom(dev, sd);
+			break;
+		default:
+			ret = pscsi_create_type_other(dev, sd);
+			break;
+		}
+
+		if (ret) {
+			if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
+				scsi_host_put(sh);
+			else if (legacy_mode_enable) {
+				pscsi_pmode_enable_hba(hba, 0);
+				hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
+			}
+			pdv->pdv_sd = NULL;
+			return ret;
+		}
+		return 0;
+	}
+	spin_unlock_irq(sh->host_lock);
+
+	pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
+		pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
+
+	if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
+		scsi_host_put(sh);
+	else if (legacy_mode_enable) {
+		pscsi_pmode_enable_hba(hba, 0);
+		hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
+	}
+
+	return -ENODEV;
+}
+
+static void pscsi_free_device(struct se_device *dev)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	struct scsi_device *sd = pdv->pdv_sd;
+
+	if (sd) {
+		/*
+		 * Release exclusive pSCSI internal struct block_device claim for
+		 * struct scsi_device with TYPE_DISK from pscsi_create_type_disk()
+		 */
+		if ((sd->type == TYPE_DISK) && pdv->pdv_bd) {
+			blkdev_put(pdv->pdv_bd,
+				   FMODE_WRITE|FMODE_READ|FMODE_EXCL);
+			pdv->pdv_bd = NULL;
+		}
+		/*
+		 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
+		 * to struct Scsi_Host now.
+		 */
+		if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
+		    (phv->phv_lld_host != NULL))
+			scsi_host_put(phv->phv_lld_host);
+		else if (pdv->pdv_lld_host)
+			scsi_host_put(pdv->pdv_lld_host);
+
+		if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
+			scsi_device_put(sd);
+
+		pdv->pdv_sd = NULL;
+	}
+
+	kfree(pdv);
+}
+
+static void pscsi_transport_complete(struct se_cmd *cmd, struct scatterlist *sg,
+				     unsigned char *sense_buffer)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
+	struct scsi_device *sd = pdv->pdv_sd;
+	int result;
+	struct pscsi_plugin_task *pt = cmd->priv;
+	unsigned char *cdb;
+	/*
+	 * Special case for REPORT_LUNs handling where pscsi_plugin_task has
+	 * not been allocated because TCM is handling the emulation directly.
+	 */
+	if (!pt)
+		return;
+
+	cdb = &pt->pscsi_cdb[0];
+	result = pt->pscsi_result;
+	/*
+	 * Hack to make sure that Write-Protect modepage is set if R/O mode is
+	 * forced.
+	 */
+	if (!cmd->se_deve || !cmd->data_length)
+		goto after_mode_sense;
+
+	if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
+	     (status_byte(result) << 1) == SAM_STAT_GOOD) {
+		if (cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY) {
+			unsigned char *buf;
+
+			buf = transport_kmap_data_sg(cmd);
+			if (!buf)
+				; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
+
+			if (cdb[0] == MODE_SENSE_10) {
+				if (!(buf[3] & 0x80))
+					buf[3] |= 0x80;
+			} else {
+				if (!(buf[2] & 0x80))
+					buf[2] |= 0x80;
+			}
+
+			transport_kunmap_data_sg(cmd);
+		}
+	}
+after_mode_sense:
+
+	if (sd->type != TYPE_TAPE || !cmd->data_length)
+		goto after_mode_select;
+
+	/*
+	 * Hack to correctly obtain the initiator requested blocksize for
+	 * TYPE_TAPE.  Since this value is dependent upon each tape media,
+	 * struct scsi_device->sector_size will not contain the correct value
+	 * by default, so we go ahead and set it so
+	 * TRANSPORT(dev)->get_blockdev() returns the correct value to the
+	 * storage engine.
+	 */
+	if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
+	      (status_byte(result) << 1) == SAM_STAT_GOOD) {
+		unsigned char *buf;
+		u16 bdl;
+		u32 blocksize;
+
+		buf = sg_virt(&sg[0]);
+		if (!buf) {
+			pr_err("Unable to get buf for scatterlist\n");
+			goto after_mode_select;
+		}
+
+		if (cdb[0] == MODE_SELECT)
+			bdl = (buf[3]);
+		else
+			bdl = (buf[6] << 8) | (buf[7]);
+
+		if (!bdl)
+			goto after_mode_select;
+
+		if (cdb[0] == MODE_SELECT)
+			blocksize = (buf[9] << 16) | (buf[10] << 8) |
+					(buf[11]);
+		else
+			blocksize = (buf[13] << 16) | (buf[14] << 8) |
+					(buf[15]);
+
+		sd->sector_size = blocksize;
+	}
+after_mode_select:
+
+	if (sense_buffer && (status_byte(result) & CHECK_CONDITION)) {
+		memcpy(sense_buffer, pt->pscsi_sense, TRANSPORT_SENSE_BUFFER);
+		cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
+	}
+}
+
+enum {
+	Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
+	Opt_scsi_lun_id, Opt_err
+};
+
+static match_table_t tokens = {
+	{Opt_scsi_host_id, "scsi_host_id=%d"},
+	{Opt_scsi_channel_id, "scsi_channel_id=%d"},
+	{Opt_scsi_target_id, "scsi_target_id=%d"},
+	{Opt_scsi_lun_id, "scsi_lun_id=%d"},
+	{Opt_err, NULL}
+};
+
+static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
+		const char *page, ssize_t count)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	char *orig, *ptr, *opts;
+	substring_t args[MAX_OPT_ARGS];
+	int ret = 0, arg, token;
+
+	opts = kstrdup(page, GFP_KERNEL);
+	if (!opts)
+		return -ENOMEM;
+
+	orig = opts;
+
+	while ((ptr = strsep(&opts, ",\n")) != NULL) {
+		if (!*ptr)
+			continue;
+
+		token = match_token(ptr, tokens, args);
+		switch (token) {
+		case Opt_scsi_host_id:
+			if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
+				pr_err("PSCSI[%d]: Unable to accept"
+					" scsi_host_id while phv_mode =="
+					" PHV_LLD_SCSI_HOST_NO\n",
+					phv->phv_host_id);
+				ret = -EINVAL;
+				goto out;
+			}
+			ret = match_int(args, &arg);
+			if (ret)
+				goto out;
+			pdv->pdv_host_id = arg;
+			pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
+				" %d\n", phv->phv_host_id, pdv->pdv_host_id);
+			pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
+			break;
+		case Opt_scsi_channel_id:
+			ret = match_int(args, &arg);
+			if (ret)
+				goto out;
+			pdv->pdv_channel_id = arg;
+			pr_debug("PSCSI[%d]: Referencing SCSI Channel"
+				" ID: %d\n",  phv->phv_host_id,
+				pdv->pdv_channel_id);
+			pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
+			break;
+		case Opt_scsi_target_id:
+			ret = match_int(args, &arg);
+			if (ret)
+				goto out;
+			pdv->pdv_target_id = arg;
+			pr_debug("PSCSI[%d]: Referencing SCSI Target"
+				" ID: %d\n", phv->phv_host_id,
+				pdv->pdv_target_id);
+			pdv->pdv_flags |= PDF_HAS_TARGET_ID;
+			break;
+		case Opt_scsi_lun_id:
+			ret = match_int(args, &arg);
+			if (ret)
+				goto out;
+			pdv->pdv_lun_id = arg;
+			pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
+				" %d\n", phv->phv_host_id, pdv->pdv_lun_id);
+			pdv->pdv_flags |= PDF_HAS_LUN_ID;
+			break;
+		default:
+			break;
+		}
+	}
+
+out:
+	kfree(orig);
+	return (!ret) ? count : ret;
+}
+
+static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
+{
+	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct scsi_device *sd = pdv->pdv_sd;
+	unsigned char host_id[16];
+	ssize_t bl;
+	int i;
+
+	if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
+		snprintf(host_id, 16, "%d", pdv->pdv_host_id);
+	else
+		snprintf(host_id, 16, "PHBA Mode");
+
+	bl = sprintf(b, "SCSI Device Bus Location:"
+		" Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
+		pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
+		host_id);
+
+	if (sd) {
+		bl += sprintf(b + bl, "        ");
+		bl += sprintf(b + bl, "Vendor: ");
+		for (i = 0; i < 8; i++) {
+			if (ISPRINT(sd->vendor[i]))   /* printable character? */
+				bl += sprintf(b + bl, "%c", sd->vendor[i]);
+			else
+				bl += sprintf(b + bl, " ");
+		}
+		bl += sprintf(b + bl, " Model: ");
+		for (i = 0; i < 16; i++) {
+			if (ISPRINT(sd->model[i]))   /* printable character ? */
+				bl += sprintf(b + bl, "%c", sd->model[i]);
+			else
+				bl += sprintf(b + bl, " ");
+		}
+		bl += sprintf(b + bl, " Rev: ");
+		for (i = 0; i < 4; i++) {
+			if (ISPRINT(sd->rev[i]))   /* printable character ? */
+				bl += sprintf(b + bl, "%c", sd->rev[i]);
+			else
+				bl += sprintf(b + bl, " ");
+		}
+		bl += sprintf(b + bl, "\n");
+	}
+	return bl;
+}
+
+static void pscsi_bi_endio(struct bio *bio, int error)
+{
+	bio_put(bio);
+}
+
+static inline struct bio *pscsi_get_bio(int nr_vecs)
+{
+	struct bio *bio;
+	/*
+	 * Use bio_malloc() following the comment in for bio -> struct request
+	 * in block/blk-core.c:blk_make_request()
+	 */
+	bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
+	if (!bio) {
+		pr_err("PSCSI: bio_kmalloc() failed\n");
+		return NULL;
+	}
+	bio->bi_end_io = pscsi_bi_endio;
+
+	return bio;
+}
+
+static sense_reason_t
+pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
+		enum dma_data_direction data_direction, struct bio **hbio)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
+	struct bio *bio = NULL, *tbio = NULL;
+	struct page *page;
+	struct scatterlist *sg;
+	u32 data_len = cmd->data_length, i, len, bytes, off;
+	int nr_pages = (cmd->data_length + sgl[0].offset +
+			PAGE_SIZE - 1) >> PAGE_SHIFT;
+	int nr_vecs = 0, rc;
+	int rw = (data_direction == DMA_TO_DEVICE);
+
+	*hbio = NULL;
+
+	pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
+
+	for_each_sg(sgl, sg, sgl_nents, i) {
+		page = sg_page(sg);
+		off = sg->offset;
+		len = sg->length;
+
+		pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
+			page, len, off);
+
+		/*
+		 * We only have one page of data in each sg element,
+		 * we can not cross a page boundary.
+		 */
+		if (off + len > PAGE_SIZE)
+			goto fail;
+
+		if (len > 0 && data_len > 0) {
+			bytes = min_t(unsigned int, len, PAGE_SIZE - off);
+			bytes = min(bytes, data_len);
+
+			if (!bio) {
+				nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
+				nr_pages -= nr_vecs;
+				/*
+				 * Calls bio_kmalloc() and sets bio->bi_end_io()
+				 */
+				bio = pscsi_get_bio(nr_vecs);
+				if (!bio)
+					goto fail;
+
+				if (rw)
+					bio->bi_rw |= REQ_WRITE;
+
+				pr_debug("PSCSI: Allocated bio: %p,"
+					" dir: %s nr_vecs: %d\n", bio,
+					(rw) ? "rw" : "r", nr_vecs);
+				/*
+				 * Set *hbio pointer to handle the case:
+				 * nr_pages > BIO_MAX_PAGES, where additional
+				 * bios need to be added to complete a given
+				 * command.
+				 */
+				if (!*hbio)
+					*hbio = tbio = bio;
+				else
+					tbio = tbio->bi_next = bio;
+			}
+
+			pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
+				" bio: %p page: %p len: %d off: %d\n", i, bio,
+				page, len, off);
+
+			rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
+					bio, page, bytes, off);
+			if (rc != bytes)
+				goto fail;
+
+			pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
+				bio->bi_vcnt, nr_vecs);
+
+			if (bio->bi_vcnt > nr_vecs) {
+				pr_debug("PSCSI: Reached bio->bi_vcnt max:"
+					" %d i: %d bio: %p, allocating another"
+					" bio\n", bio->bi_vcnt, i, bio);
+				/*
+				 * Clear the pointer so that another bio will
+				 * be allocated with pscsi_get_bio() above, the
+				 * current bio has already been set *tbio and
+				 * bio->bi_next.
+				 */
+				bio = NULL;
+			}
+
+			data_len -= bytes;
+		}
+	}
+
+	return 0;
+fail:
+	while (*hbio) {
+		bio = *hbio;
+		*hbio = (*hbio)->bi_next;
+		bio_endio(bio, 0);	/* XXX: should be error */
+	}
+	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+}
+
+static sense_reason_t
+pscsi_parse_cdb(struct se_cmd *cmd)
+{
+	if (cmd->se_cmd_flags & SCF_BIDI)
+		return TCM_UNSUPPORTED_SCSI_OPCODE;
+
+	return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
+}
+
+static sense_reason_t
+pscsi_execute_cmd(struct se_cmd *cmd)
+{
+	struct scatterlist *sgl = cmd->t_data_sg;
+	u32 sgl_nents = cmd->t_data_nents;
+	enum dma_data_direction data_direction = cmd->data_direction;
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
+	struct pscsi_plugin_task *pt;
+	struct request *req;
+	struct bio *hbio;
+	sense_reason_t ret;
+
+	/*
+	 * Dynamically alloc cdb space, since it may be larger than
+	 * TCM_MAX_COMMAND_SIZE
+	 */
+	pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
+	if (!pt) {
+		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+	}
+	cmd->priv = pt;
+
+	memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
+		scsi_command_size(cmd->t_task_cdb));
+
+	if (!sgl) {
+		req = blk_get_request(pdv->pdv_sd->request_queue,
+				(data_direction == DMA_TO_DEVICE),
+				GFP_KERNEL);
+		if (IS_ERR(req)) {
+			pr_err("PSCSI: blk_get_request() failed\n");
+			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+			goto fail;
+		}
+
+		blk_rq_set_block_pc(req);
+	} else {
+		BUG_ON(!cmd->data_length);
+
+		ret = pscsi_map_sg(cmd, sgl, sgl_nents, data_direction, &hbio);
+		if (ret)
+			goto fail;
+
+		req = blk_make_request(pdv->pdv_sd->request_queue, hbio,
+				       GFP_KERNEL);
+		if (IS_ERR(req)) {
+			pr_err("pSCSI: blk_make_request() failed\n");
+			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+			goto fail_free_bio;
+		}
+	}
+
+	req->end_io = pscsi_req_done;
+	req->end_io_data = cmd;
+	req->cmd_len = scsi_command_size(pt->pscsi_cdb);
+	req->cmd = &pt->pscsi_cdb[0];
+	req->sense = &pt->pscsi_sense[0];
+	req->sense_len = 0;
+	if (pdv->pdv_sd->type == TYPE_DISK)
+		req->timeout = PS_TIMEOUT_DISK;
+	else
+		req->timeout = PS_TIMEOUT_OTHER;
+	req->retries = PS_RETRY;
+
+	blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
+			(cmd->sam_task_attr == TCM_HEAD_TAG),
+			pscsi_req_done);
+
+	return 0;
+
+fail_free_bio:
+	while (hbio) {
+		struct bio *bio = hbio;
+		hbio = hbio->bi_next;
+		bio_endio(bio, 0);	/* XXX: should be error */
+	}
+	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+fail:
+	kfree(pt);
+	return ret;
+}
+
+/*	pscsi_get_device_type():
+ *
+ *
+ */
+static u32 pscsi_get_device_type(struct se_device *dev)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+	struct scsi_device *sd = pdv->pdv_sd;
+
+	return (sd) ? sd->type : TYPE_NO_LUN;
+}
+
+static sector_t pscsi_get_blocks(struct se_device *dev)
+{
+	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
+
+	if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
+		return pdv->pdv_bd->bd_part->nr_sects;
+
+	dump_stack();
+	return 0;
+}
+
+static void pscsi_req_done(struct request *req, int uptodate)
+{
+	struct se_cmd *cmd = req->end_io_data;
+	struct pscsi_plugin_task *pt = cmd->priv;
+
+	pt->pscsi_result = req->errors;
+	pt->pscsi_resid = req->resid_len;
+
+	cmd->scsi_status = status_byte(pt->pscsi_result) << 1;
+	if (cmd->scsi_status) {
+		pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
+			" 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
+			pt->pscsi_result);
+	}
+
+	switch (host_byte(pt->pscsi_result)) {
+	case DID_OK:
+		target_complete_cmd(cmd, cmd->scsi_status);
+		break;
+	default:
+		pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
+			" 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
+			pt->pscsi_result);
+		target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
+		break;
+	}
+
+	__blk_put_request(req->q, req);
+	kfree(pt);
+}
+
+DEF_TB_DEV_ATTRIB_RO(pscsi, hw_pi_prot_type);
+TB_DEV_ATTR_RO(pscsi, hw_pi_prot_type);
+
+DEF_TB_DEV_ATTRIB_RO(pscsi, hw_block_size);
+TB_DEV_ATTR_RO(pscsi, hw_block_size);
+
+DEF_TB_DEV_ATTRIB_RO(pscsi, hw_max_sectors);
+TB_DEV_ATTR_RO(pscsi, hw_max_sectors);
+
+DEF_TB_DEV_ATTRIB_RO(pscsi, hw_queue_depth);
+TB_DEV_ATTR_RO(pscsi, hw_queue_depth);
+
+static struct configfs_attribute *pscsi_backend_dev_attrs[] = {
+	&pscsi_dev_attrib_hw_pi_prot_type.attr,
+	&pscsi_dev_attrib_hw_block_size.attr,
+	&pscsi_dev_attrib_hw_max_sectors.attr,
+	&pscsi_dev_attrib_hw_queue_depth.attr,
+	NULL,
+};
+
+static struct se_subsystem_api pscsi_template = {
+	.name			= "pscsi",
+	.owner			= THIS_MODULE,
+	.transport_flags	= TRANSPORT_FLAG_PASSTHROUGH,
+	.attach_hba		= pscsi_attach_hba,
+	.detach_hba		= pscsi_detach_hba,
+	.pmode_enable_hba	= pscsi_pmode_enable_hba,
+	.alloc_device		= pscsi_alloc_device,
+	.configure_device	= pscsi_configure_device,
+	.free_device		= pscsi_free_device,
+	.transport_complete	= pscsi_transport_complete,
+	.parse_cdb		= pscsi_parse_cdb,
+	.set_configfs_dev_params = pscsi_set_configfs_dev_params,
+	.show_configfs_dev_params = pscsi_show_configfs_dev_params,
+	.get_device_type	= pscsi_get_device_type,
+	.get_blocks		= pscsi_get_blocks,
+};
+
+static int __init pscsi_module_init(void)
+{
+	struct target_backend_cits *tbc = &pscsi_template.tb_cits;
+
+	target_core_setup_sub_cits(&pscsi_template);
+	tbc->tb_dev_attrib_cit.ct_attrs = pscsi_backend_dev_attrs;
+
+	return transport_subsystem_register(&pscsi_template);
+}
+
+static void __exit pscsi_module_exit(void)
+{
+	transport_subsystem_release(&pscsi_template);
+}
+
+MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
+MODULE_AUTHOR("nab@Linux-iSCSI.org");
+MODULE_LICENSE("GPL");
+
+module_init(pscsi_module_init);
+module_exit(pscsi_module_exit);