Adding upstream version 6.1.76.upstream/6.1.76

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

1 files changed, 1034 insertions, 0 deletions

diff --git a/drivers/target/target_core_xcopy.c b/drivers/target/target_core_xcopy.c
new file mode 100644
index 000000000..d2900d375
--- /dev/null
+++ b/drivers/target/target_core_xcopy.c
@@ -0,0 +1,1034 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ * Filename: target_core_xcopy.c
+ *
+ * This file contains support for SPC-4 Extended-Copy offload with generic
+ * TCM backends.
+ *
+ * Copyright (c) 2011-2013 Datera, Inc. All rights reserved.
+ *
+ * Author:
+ * Nicholas A. Bellinger <nab@daterainc.com>
+ *
+ ******************************************************************************/
+
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/configfs.h>
+#include <linux/ratelimit.h>
+#include <scsi/scsi_proto.h>
+#include <asm/unaligned.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+#include <target/target_core_fabric.h>
+
+#include "target_core_internal.h"
+#include "target_core_pr.h"
+#include "target_core_ua.h"
+#include "target_core_xcopy.h"
+
+static struct workqueue_struct *xcopy_wq = NULL;
+
+static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop);
+
+/**
+ * target_xcopy_locate_se_dev_e4_iter - compare XCOPY NAA device identifiers
+ *
+ * @se_dev: device being considered for match
+ * @dev_wwn: XCOPY requested NAA dev_wwn
+ * @return: 1 on match, 0 on no-match
+ */
+static int target_xcopy_locate_se_dev_e4_iter(struct se_device *se_dev,
+					      const unsigned char *dev_wwn)
+{
+	unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN];
+	int rc;
+
+	if (!se_dev->dev_attrib.emulate_3pc) {
+		pr_debug("XCOPY: emulate_3pc disabled on se_dev %p\n", se_dev);
+		return 0;
+	}
+
+	memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
+	spc_gen_naa_6h_vendor_specific(se_dev, &tmp_dev_wwn[0]);
+
+	rc = memcmp(&tmp_dev_wwn[0], dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN);
+	if (rc != 0) {
+		pr_debug("XCOPY: skip non-matching: %*ph\n",
+			 XCOPY_NAA_IEEE_REGEX_LEN, tmp_dev_wwn);
+		return 0;
+	}
+	pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev);
+
+	return 1;
+}
+
+static int target_xcopy_locate_se_dev_e4(struct se_session *sess,
+					const unsigned char *dev_wwn,
+					struct se_device **_found_dev,
+					struct percpu_ref **_found_lun_ref)
+{
+	struct se_dev_entry *deve;
+	struct se_node_acl *nacl;
+	struct se_lun *this_lun = NULL;
+	struct se_device *found_dev = NULL;
+
+	/* cmd with NULL sess indicates no associated $FABRIC_MOD */
+	if (!sess)
+		goto err_out;
+
+	pr_debug("XCOPY 0xe4: searching for: %*ph\n",
+		 XCOPY_NAA_IEEE_REGEX_LEN, dev_wwn);
+
+	nacl = sess->se_node_acl;
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
+		struct se_device *this_dev;
+		int rc;
+
+		this_lun = deve->se_lun;
+		this_dev = rcu_dereference_raw(this_lun->lun_se_dev);
+
+		rc = target_xcopy_locate_se_dev_e4_iter(this_dev, dev_wwn);
+		if (rc) {
+			if (percpu_ref_tryget_live(&this_lun->lun_ref))
+				found_dev = this_dev;
+			break;
+		}
+	}
+	rcu_read_unlock();
+	if (found_dev == NULL)
+		goto err_out;
+
+	pr_debug("lun_ref held for se_dev: %p se_dev->se_dev_group: %p\n",
+		 found_dev, &found_dev->dev_group);
+	*_found_dev = found_dev;
+	*_found_lun_ref = &this_lun->lun_ref;
+	return 0;
+err_out:
+	pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n");
+	return -EINVAL;
+}
+
+static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
+				unsigned char *p, unsigned short cscd_index)
+{
+	unsigned char *desc = p;
+	unsigned short ript;
+	u8 desig_len;
+	/*
+	 * Extract RELATIVE INITIATOR PORT IDENTIFIER
+	 */
+	ript = get_unaligned_be16(&desc[2]);
+	pr_debug("XCOPY 0xe4: RELATIVE INITIATOR PORT IDENTIFIER: %hu\n", ript);
+	/*
+	 * Check for supported code set, association, and designator type
+	 */
+	if ((desc[4] & 0x0f) != 0x1) {
+		pr_err("XCOPY 0xe4: code set of non binary type not supported\n");
+		return -EINVAL;
+	}
+	if ((desc[5] & 0x30) != 0x00) {
+		pr_err("XCOPY 0xe4: association other than LUN not supported\n");
+		return -EINVAL;
+	}
+	if ((desc[5] & 0x0f) != 0x3) {
+		pr_err("XCOPY 0xe4: designator type unsupported: 0x%02x\n",
+				(desc[5] & 0x0f));
+		return -EINVAL;
+	}
+	/*
+	 * Check for matching 16 byte length for NAA IEEE Registered Extended
+	 * Assigned designator
+	 */
+	desig_len = desc[7];
+	if (desig_len != XCOPY_NAA_IEEE_REGEX_LEN) {
+		pr_err("XCOPY 0xe4: invalid desig_len: %d\n", (int)desig_len);
+		return -EINVAL;
+	}
+	pr_debug("XCOPY 0xe4: desig_len: %d\n", (int)desig_len);
+	/*
+	 * Check for NAA IEEE Registered Extended Assigned header..
+	 */
+	if ((desc[8] & 0xf0) != 0x60) {
+		pr_err("XCOPY 0xe4: Unsupported DESIGNATOR TYPE: 0x%02x\n",
+					(desc[8] & 0xf0));
+		return -EINVAL;
+	}
+
+	if (cscd_index != xop->stdi && cscd_index != xop->dtdi) {
+		pr_debug("XCOPY 0xe4: ignoring CSCD entry %d - neither src nor "
+			 "dest\n", cscd_index);
+		return 0;
+	}
+
+	if (cscd_index == xop->stdi) {
+		memcpy(&xop->src_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
+		/*
+		 * Determine if the source designator matches the local device
+		 */
+		if (!memcmp(&xop->local_dev_wwn[0], &xop->src_tid_wwn[0],
+				XCOPY_NAA_IEEE_REGEX_LEN)) {
+			xop->op_origin = XCOL_SOURCE_RECV_OP;
+			xop->src_dev = se_cmd->se_dev;
+			pr_debug("XCOPY 0xe4: Set xop->src_dev %p from source"
+					" received xop\n", xop->src_dev);
+		}
+	}
+
+	if (cscd_index == xop->dtdi) {
+		memcpy(&xop->dst_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
+		/*
+		 * Determine if the destination designator matches the local
+		 * device. If @cscd_index corresponds to both source (stdi) and
+		 * destination (dtdi), or dtdi comes after stdi, then
+		 * XCOL_DEST_RECV_OP wins.
+		 */
+		if (!memcmp(&xop->local_dev_wwn[0], &xop->dst_tid_wwn[0],
+				XCOPY_NAA_IEEE_REGEX_LEN)) {
+			xop->op_origin = XCOL_DEST_RECV_OP;
+			xop->dst_dev = se_cmd->se_dev;
+			pr_debug("XCOPY 0xe4: Set xop->dst_dev: %p from destination"
+				" received xop\n", xop->dst_dev);
+		}
+	}
+
+	return 0;
+}
+
+static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd,
+				struct xcopy_op *xop, unsigned char *p,
+				unsigned short tdll, sense_reason_t *sense_ret)
+{
+	struct se_device *local_dev = se_cmd->se_dev;
+	unsigned char *desc = p;
+	int offset = tdll % XCOPY_TARGET_DESC_LEN, rc;
+	unsigned short cscd_index = 0;
+	unsigned short start = 0;
+
+	*sense_ret = TCM_INVALID_PARAMETER_LIST;
+
+	if (offset != 0) {
+		pr_err("XCOPY target descriptor list length is not"
+			" multiple of %d\n", XCOPY_TARGET_DESC_LEN);
+		*sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
+		return -EINVAL;
+	}
+	if (tdll > RCR_OP_MAX_TARGET_DESC_COUNT * XCOPY_TARGET_DESC_LEN) {
+		pr_err("XCOPY target descriptor supports a maximum"
+			" two src/dest descriptors, tdll: %hu too large..\n", tdll);
+		/* spc4r37 6.4.3.4 CSCD DESCRIPTOR LIST LENGTH field */
+		*sense_ret = TCM_TOO_MANY_TARGET_DESCS;
+		return -EINVAL;
+	}
+	/*
+	 * Generate an IEEE Registered Extended designator based upon the
+	 * se_device the XCOPY was received upon..
+	 */
+	memset(&xop->local_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
+	spc_gen_naa_6h_vendor_specific(local_dev, &xop->local_dev_wwn[0]);
+
+	while (start < tdll) {
+		/*
+		 * Check target descriptor identification with 0xE4 type, and
+		 * compare the current index with the CSCD descriptor IDs in
+		 * the segment descriptor. Use VPD 0x83 WWPN matching ..
+		 */
+		switch (desc[0]) {
+		case 0xe4:
+			rc = target_xcopy_parse_tiddesc_e4(se_cmd, xop,
+							&desc[0], cscd_index);
+			if (rc != 0)
+				goto out;
+			start += XCOPY_TARGET_DESC_LEN;
+			desc += XCOPY_TARGET_DESC_LEN;
+			cscd_index++;
+			break;
+		default:
+			pr_err("XCOPY unsupported descriptor type code:"
+					" 0x%02x\n", desc[0]);
+			*sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
+			goto out;
+		}
+	}
+
+	switch (xop->op_origin) {
+	case XCOL_SOURCE_RECV_OP:
+		rc = target_xcopy_locate_se_dev_e4(se_cmd->se_sess,
+						xop->dst_tid_wwn,
+						&xop->dst_dev,
+						&xop->remote_lun_ref);
+		break;
+	case XCOL_DEST_RECV_OP:
+		rc = target_xcopy_locate_se_dev_e4(se_cmd->se_sess,
+						xop->src_tid_wwn,
+						&xop->src_dev,
+						&xop->remote_lun_ref);
+		break;
+	default:
+		pr_err("XCOPY CSCD descriptor IDs not found in CSCD list - "
+			"stdi: %hu dtdi: %hu\n", xop->stdi, xop->dtdi);
+		rc = -EINVAL;
+		break;
+	}
+	/*
+	 * If a matching IEEE NAA 0x83 descriptor for the requested device
+	 * is not located on this node, return COPY_ABORTED with ASQ/ASQC
+	 * 0x0d/0x02 - COPY_TARGET_DEVICE_NOT_REACHABLE to request the
+	 * initiator to fall back to normal copy method.
+	 */
+	if (rc < 0) {
+		*sense_ret = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
+		goto out;
+	}
+
+	pr_debug("XCOPY TGT desc: Source dev: %p NAA IEEE WWN: 0x%16phN\n",
+		 xop->src_dev, &xop->src_tid_wwn[0]);
+	pr_debug("XCOPY TGT desc: Dest dev: %p NAA IEEE WWN: 0x%16phN\n",
+		 xop->dst_dev, &xop->dst_tid_wwn[0]);
+
+	return cscd_index;
+
+out:
+	return -EINVAL;
+}
+
+static int target_xcopy_parse_segdesc_02(struct xcopy_op *xop, unsigned char *p)
+{
+	unsigned char *desc = p;
+	int dc = (desc[1] & 0x02);
+	unsigned short desc_len;
+
+	desc_len = get_unaligned_be16(&desc[2]);
+	if (desc_len != 0x18) {
+		pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
+				" %hu\n", desc_len);
+		return -EINVAL;
+	}
+
+	xop->stdi = get_unaligned_be16(&desc[4]);
+	xop->dtdi = get_unaligned_be16(&desc[6]);
+
+	if (xop->stdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX ||
+	    xop->dtdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX) {
+		pr_err("XCOPY segment desc 0x02: unsupported CSCD ID > 0x%x; stdi: %hu dtdi: %hu\n",
+			XCOPY_CSCD_DESC_ID_LIST_OFF_MAX, xop->stdi, xop->dtdi);
+		return -EINVAL;
+	}
+
+	pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
+		desc_len, xop->stdi, xop->dtdi, dc);
+
+	xop->nolb = get_unaligned_be16(&desc[10]);
+	xop->src_lba = get_unaligned_be64(&desc[12]);
+	xop->dst_lba = get_unaligned_be64(&desc[20]);
+	pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
+		xop->nolb, (unsigned long long)xop->src_lba,
+		(unsigned long long)xop->dst_lba);
+
+	return 0;
+}
+
+static int target_xcopy_parse_segment_descriptors(struct xcopy_op *xop,
+				unsigned char *p, unsigned int sdll,
+				sense_reason_t *sense_ret)
+{
+	unsigned char *desc = p;
+	unsigned int start = 0;
+	int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
+
+	*sense_ret = TCM_INVALID_PARAMETER_LIST;
+
+	if (offset != 0) {
+		pr_err("XCOPY segment descriptor list length is not"
+			" multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
+		*sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
+		return -EINVAL;
+	}
+	if (sdll > RCR_OP_MAX_SG_DESC_COUNT * XCOPY_SEGMENT_DESC_LEN) {
+		pr_err("XCOPY supports %u segment descriptor(s), sdll: %u too"
+			" large..\n", RCR_OP_MAX_SG_DESC_COUNT, sdll);
+		/* spc4r37 6.4.3.5 SEGMENT DESCRIPTOR LIST LENGTH field */
+		*sense_ret = TCM_TOO_MANY_SEGMENT_DESCS;
+		return -EINVAL;
+	}
+
+	while (start < sdll) {
+		/*
+		 * Check segment descriptor type code for block -> block
+		 */
+		switch (desc[0]) {
+		case 0x02:
+			rc = target_xcopy_parse_segdesc_02(xop, desc);
+			if (rc < 0)
+				goto out;
+
+			ret++;
+			start += XCOPY_SEGMENT_DESC_LEN;
+			desc += XCOPY_SEGMENT_DESC_LEN;
+			break;
+		default:
+			pr_err("XCOPY unsupported segment descriptor"
+				"type: 0x%02x\n", desc[0]);
+			*sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
+			goto out;
+		}
+	}
+
+	return ret;
+
+out:
+	return -EINVAL;
+}
+
+/*
+ * Start xcopy_pt ops
+ */
+
+struct xcopy_pt_cmd {
+	struct se_cmd se_cmd;
+	struct completion xpt_passthrough_sem;
+	unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
+};
+
+struct se_portal_group xcopy_pt_tpg;
+static struct se_session xcopy_pt_sess;
+static struct se_node_acl xcopy_pt_nacl;
+
+static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
+{
+        return 0;
+}
+
+static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
+{
+	if (xop->op_origin == XCOL_SOURCE_RECV_OP)
+		pr_debug("putting dst lun_ref for %p\n", xop->dst_dev);
+	else
+		pr_debug("putting src lun_ref for %p\n", xop->src_dev);
+
+	percpu_ref_put(xop->remote_lun_ref);
+}
+
+static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
+{
+	struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
+				struct xcopy_pt_cmd, se_cmd);
+
+	/* xpt_cmd is on the stack, nothing to free here */
+	pr_debug("xpt_cmd done: %p\n", xpt_cmd);
+}
+
+static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
+{
+	struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
+				struct xcopy_pt_cmd, se_cmd);
+
+	complete(&xpt_cmd->xpt_passthrough_sem);
+	return 0;
+}
+
+static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
+{
+	return 0;
+}
+
+static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
+{
+	return 0;
+}
+
+static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
+{
+	return 0;
+}
+
+static const struct target_core_fabric_ops xcopy_pt_tfo = {
+	.fabric_name		= "xcopy-pt",
+	.get_cmd_state		= xcopy_pt_get_cmd_state,
+	.release_cmd		= xcopy_pt_release_cmd,
+	.check_stop_free	= xcopy_pt_check_stop_free,
+	.write_pending		= xcopy_pt_write_pending,
+	.queue_data_in		= xcopy_pt_queue_data_in,
+	.queue_status		= xcopy_pt_queue_status,
+};
+
+/*
+ * End xcopy_pt_ops
+ */
+
+int target_xcopy_setup_pt(void)
+{
+	xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
+	if (!xcopy_wq) {
+		pr_err("Unable to allocate xcopy_wq\n");
+		return -ENOMEM;
+	}
+
+	memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
+	INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
+	INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
+
+	xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
+
+	memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
+	INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
+	INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
+	memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
+	transport_init_session(&xcopy_pt_sess);
+
+	xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
+	xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
+
+	xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
+	xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
+
+	return 0;
+}
+
+void target_xcopy_release_pt(void)
+{
+	if (xcopy_wq)
+		destroy_workqueue(xcopy_wq);
+}
+
+/*
+ * target_xcopy_setup_pt_cmd - set up a pass-through command
+ * @xpt_cmd:	 Data structure to initialize.
+ * @xop:	 Describes the XCOPY operation received from an initiator.
+ * @se_dev:	 Backend device to associate with @xpt_cmd if
+ *		 @remote_port == true.
+ * @cdb:	 SCSI CDB to be copied into @xpt_cmd.
+ * @remote_port: If false, use the LUN through which the XCOPY command has
+ *		 been received. If true, use @se_dev->xcopy_lun.
+ *
+ * Set up a SCSI command (READ or WRITE) that will be used to execute an
+ * XCOPY command.
+ */
+static int target_xcopy_setup_pt_cmd(
+	struct xcopy_pt_cmd *xpt_cmd,
+	struct xcopy_op *xop,
+	struct se_device *se_dev,
+	unsigned char *cdb,
+	bool remote_port)
+{
+	struct se_cmd *cmd = &xpt_cmd->se_cmd;
+
+	/*
+	 * Setup LUN+port to honor reservations based upon xop->op_origin for
+	 * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
+	 */
+	if (remote_port) {
+		cmd->se_lun = &se_dev->xcopy_lun;
+		cmd->se_dev = se_dev;
+	} else {
+		cmd->se_lun = xop->xop_se_cmd->se_lun;
+		cmd->se_dev = xop->xop_se_cmd->se_dev;
+	}
+	cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
+
+	if (target_cmd_init_cdb(cmd, cdb, GFP_KERNEL))
+		return -EINVAL;
+
+	cmd->tag = 0;
+	if (target_cmd_parse_cdb(cmd))
+		return -EINVAL;
+
+	if (transport_generic_map_mem_to_cmd(cmd, xop->xop_data_sg,
+					xop->xop_data_nents, NULL, 0))
+		return -EINVAL;
+
+	pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
+		 " %u\n", cmd->t_data_sg, cmd->t_data_nents);
+
+	return 0;
+}
+
+static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
+{
+	struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
+	sense_reason_t sense_rc;
+
+	sense_rc = transport_generic_new_cmd(se_cmd);
+	if (sense_rc)
+		return -EINVAL;
+
+	if (se_cmd->data_direction == DMA_TO_DEVICE)
+		target_execute_cmd(se_cmd);
+
+	wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
+
+	pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
+			se_cmd->scsi_status);
+
+	return (se_cmd->scsi_status) ? -EINVAL : 0;
+}
+
+static int target_xcopy_read_source(
+	struct se_cmd *ec_cmd,
+	struct xcopy_op *xop,
+	struct se_device *src_dev,
+	sector_t src_lba,
+	u32 src_bytes)
+{
+	struct xcopy_pt_cmd xpt_cmd;
+	struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
+	u32 transfer_length_block = src_bytes / src_dev->dev_attrib.block_size;
+	int rc;
+	unsigned char cdb[16];
+	bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
+
+	memset(&xpt_cmd, 0, sizeof(xpt_cmd));
+	init_completion(&xpt_cmd.xpt_passthrough_sem);
+
+	memset(&cdb[0], 0, 16);
+	cdb[0] = READ_16;
+	put_unaligned_be64(src_lba, &cdb[2]);
+	put_unaligned_be32(transfer_length_block, &cdb[10]);
+	pr_debug("XCOPY: Built READ_16: LBA: %llu Blocks: %u Length: %u\n",
+		(unsigned long long)src_lba, transfer_length_block, src_bytes);
+
+	__target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, src_bytes,
+			  DMA_FROM_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0,
+			  NULL);
+	rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, src_dev, &cdb[0],
+				remote_port);
+	if (rc < 0) {
+		ec_cmd->scsi_status = se_cmd->scsi_status;
+		goto out;
+	}
+
+	pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
+		" memory\n", xop->xop_data_sg, xop->xop_data_nents);
+
+	rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
+	if (rc < 0)
+		ec_cmd->scsi_status = se_cmd->scsi_status;
+out:
+	transport_generic_free_cmd(se_cmd, 0);
+	return rc;
+}
+
+static int target_xcopy_write_destination(
+	struct se_cmd *ec_cmd,
+	struct xcopy_op *xop,
+	struct se_device *dst_dev,
+	sector_t dst_lba,
+	u32 dst_bytes)
+{
+	struct xcopy_pt_cmd xpt_cmd;
+	struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
+	u32 transfer_length_block = dst_bytes / dst_dev->dev_attrib.block_size;
+	int rc;
+	unsigned char cdb[16];
+	bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
+
+	memset(&xpt_cmd, 0, sizeof(xpt_cmd));
+	init_completion(&xpt_cmd.xpt_passthrough_sem);
+
+	memset(&cdb[0], 0, 16);
+	cdb[0] = WRITE_16;
+	put_unaligned_be64(dst_lba, &cdb[2]);
+	put_unaligned_be32(transfer_length_block, &cdb[10]);
+	pr_debug("XCOPY: Built WRITE_16: LBA: %llu Blocks: %u Length: %u\n",
+		(unsigned long long)dst_lba, transfer_length_block, dst_bytes);
+
+	__target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, dst_bytes,
+			  DMA_TO_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0,
+			  NULL);
+	rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, dst_dev, &cdb[0],
+				remote_port);
+	if (rc < 0) {
+		ec_cmd->scsi_status = se_cmd->scsi_status;
+		goto out;
+	}
+
+	rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
+	if (rc < 0)
+		ec_cmd->scsi_status = se_cmd->scsi_status;
+out:
+	transport_generic_free_cmd(se_cmd, 0);
+	return rc;
+}
+
+static void target_xcopy_do_work(struct work_struct *work)
+{
+	struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
+	struct se_cmd *ec_cmd = xop->xop_se_cmd;
+	struct se_device *src_dev, *dst_dev;
+	sector_t src_lba, dst_lba, end_lba;
+	unsigned long long max_bytes, max_bytes_src, max_bytes_dst, max_blocks;
+	int rc = 0;
+	unsigned short nolb;
+	unsigned int copied_bytes = 0;
+	sense_reason_t sense_rc;
+
+	sense_rc = target_parse_xcopy_cmd(xop);
+	if (sense_rc != TCM_NO_SENSE)
+		goto err_free;
+
+	if (WARN_ON_ONCE(!xop->src_dev) || WARN_ON_ONCE(!xop->dst_dev)) {
+		sense_rc = TCM_INVALID_PARAMETER_LIST;
+		goto err_free;
+	}
+
+	src_dev = xop->src_dev;
+	dst_dev = xop->dst_dev;
+	src_lba = xop->src_lba;
+	dst_lba = xop->dst_lba;
+	nolb = xop->nolb;
+	end_lba = src_lba + nolb;
+	/*
+	 * Break up XCOPY I/O into hw_max_sectors * hw_block_size sized
+	 * I/O based on the smallest max_bytes between src_dev + dst_dev
+	 */
+	max_bytes_src = (unsigned long long) src_dev->dev_attrib.hw_max_sectors *
+			src_dev->dev_attrib.hw_block_size;
+	max_bytes_dst = (unsigned long long) dst_dev->dev_attrib.hw_max_sectors *
+			dst_dev->dev_attrib.hw_block_size;
+
+	max_bytes = min_t(u64, max_bytes_src, max_bytes_dst);
+	max_bytes = min_t(u64, max_bytes, XCOPY_MAX_BYTES);
+
+	/*
+	 * Using shift instead of the division because otherwise GCC
+	 * generates __udivdi3 that is missing on i386
+	 */
+	max_blocks = max_bytes >> ilog2(src_dev->dev_attrib.block_size);
+
+	pr_debug("%s: nolb: %u, max_blocks: %llu end_lba: %llu\n", __func__,
+			nolb, max_blocks, (unsigned long long)end_lba);
+	pr_debug("%s: Starting src_lba: %llu, dst_lba: %llu\n", __func__,
+			(unsigned long long)src_lba, (unsigned long long)dst_lba);
+
+	while (nolb) {
+		u32 cur_bytes = min_t(u64, max_bytes, nolb * src_dev->dev_attrib.block_size);
+		unsigned short cur_nolb = cur_bytes / src_dev->dev_attrib.block_size;
+
+		if (cur_bytes != xop->xop_data_bytes) {
+			/*
+			 * (Re)allocate a buffer large enough to hold the XCOPY
+			 * I/O size, which can be reused each read / write loop.
+			 */
+			target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
+			rc = target_alloc_sgl(&xop->xop_data_sg,
+					      &xop->xop_data_nents,
+					      cur_bytes,
+					      false, false);
+			if (rc < 0)
+				goto out;
+			xop->xop_data_bytes = cur_bytes;
+		}
+
+		pr_debug("%s: Calling read src_dev: %p src_lba: %llu, cur_nolb: %hu\n",
+				__func__, src_dev, (unsigned long long)src_lba, cur_nolb);
+
+		rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_bytes);
+		if (rc < 0)
+			goto out;
+
+		src_lba += cur_bytes / src_dev->dev_attrib.block_size;
+		pr_debug("%s: Incremented READ src_lba to %llu\n", __func__,
+				(unsigned long long)src_lba);
+
+		pr_debug("%s: Calling write dst_dev: %p dst_lba: %llu, cur_nolb: %u\n",
+				__func__, dst_dev, (unsigned long long)dst_lba, cur_nolb);
+
+		rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
+						dst_lba, cur_bytes);
+		if (rc < 0)
+			goto out;
+
+		dst_lba += cur_bytes / dst_dev->dev_attrib.block_size;
+		pr_debug("%s: Incremented WRITE dst_lba to %llu\n", __func__,
+				(unsigned long long)dst_lba);
+
+		copied_bytes += cur_bytes;
+		nolb -= cur_bytes / src_dev->dev_attrib.block_size;
+	}
+
+	xcopy_pt_undepend_remotedev(xop);
+	target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
+	kfree(xop);
+
+	pr_debug("%s: Final src_lba: %llu, dst_lba: %llu\n", __func__,
+		(unsigned long long)src_lba, (unsigned long long)dst_lba);
+	pr_debug("%s: Blocks copied: %u, Bytes Copied: %u\n", __func__,
+		copied_bytes / dst_dev->dev_attrib.block_size, copied_bytes);
+
+	pr_debug("%s: Setting X-COPY GOOD status -> sending response\n", __func__);
+	target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
+	return;
+
+out:
+	/*
+	 * The XCOPY command was aborted after some data was transferred.
+	 * Terminate command with CHECK CONDITION status, with the sense key
+	 * set to COPY ABORTED.
+	 */
+	sense_rc = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
+	xcopy_pt_undepend_remotedev(xop);
+	target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
+
+err_free:
+	kfree(xop);
+	pr_warn_ratelimited("%s: rc: %d, sense: %u, XCOPY operation failed\n",
+			   __func__, rc, sense_rc);
+	target_complete_cmd_with_sense(ec_cmd, SAM_STAT_CHECK_CONDITION, sense_rc);
+}
+
+/*
+ * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
+ * fails.
+ */
+static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
+{
+	struct se_cmd *se_cmd = xop->xop_se_cmd;
+	unsigned char *p = NULL, *seg_desc;
+	unsigned int list_id, list_id_usage, sdll, inline_dl;
+	sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
+	int rc;
+	unsigned short tdll;
+
+	p = transport_kmap_data_sg(se_cmd);
+	if (!p) {
+		pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
+		return TCM_OUT_OF_RESOURCES;
+	}
+
+	list_id = p[0];
+	list_id_usage = (p[1] & 0x18) >> 3;
+
+	/*
+	 * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
+	 */
+	tdll = get_unaligned_be16(&p[2]);
+	sdll = get_unaligned_be32(&p[8]);
+	if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
+		pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
+		       tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
+		ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
+		goto out;
+	}
+
+	inline_dl = get_unaligned_be32(&p[12]);
+	if (inline_dl != 0) {
+		pr_err("XCOPY with non zero inline data length\n");
+		goto out;
+	}
+
+	if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
+		pr_err("XCOPY parameter truncation: data length %u too small "
+			"for tdll: %hu sdll: %u inline_dl: %u\n",
+			se_cmd->data_length, tdll, sdll, inline_dl);
+		ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
+		goto out;
+	}
+
+	pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
+		" tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
+		tdll, sdll, inline_dl);
+
+	/*
+	 * skip over the target descriptors until segment descriptors
+	 * have been passed - CSCD ids are needed to determine src and dest.
+	 */
+	seg_desc = &p[16] + tdll;
+
+	rc = target_xcopy_parse_segment_descriptors(xop, seg_desc, sdll, &ret);
+	if (rc <= 0)
+		goto out;
+
+	pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
+				rc * XCOPY_SEGMENT_DESC_LEN);
+
+	rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
+	if (rc <= 0)
+		goto out;
+
+	if (xop->src_dev->dev_attrib.block_size !=
+	    xop->dst_dev->dev_attrib.block_size) {
+		pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
+		       " block_size: %u currently unsupported\n",
+			xop->src_dev->dev_attrib.block_size,
+			xop->dst_dev->dev_attrib.block_size);
+		xcopy_pt_undepend_remotedev(xop);
+		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		goto out;
+	}
+
+	pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
+				rc * XCOPY_TARGET_DESC_LEN);
+	transport_kunmap_data_sg(se_cmd);
+	return TCM_NO_SENSE;
+
+out:
+	if (p)
+		transport_kunmap_data_sg(se_cmd);
+	return ret;
+}
+
+sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
+{
+	struct se_device *dev = se_cmd->se_dev;
+	struct xcopy_op *xop;
+	unsigned int sa;
+
+	if (!dev->dev_attrib.emulate_3pc) {
+		pr_err("EXTENDED_COPY operation explicitly disabled\n");
+		return TCM_UNSUPPORTED_SCSI_OPCODE;
+	}
+
+	sa = se_cmd->t_task_cdb[1] & 0x1f;
+	if (sa != 0x00) {
+		pr_err("EXTENDED_COPY(LID4) not supported\n");
+		return TCM_UNSUPPORTED_SCSI_OPCODE;
+	}
+
+	if (se_cmd->data_length == 0) {
+		target_complete_cmd(se_cmd, SAM_STAT_GOOD);
+		return TCM_NO_SENSE;
+	}
+	if (se_cmd->data_length < XCOPY_HDR_LEN) {
+		pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
+				se_cmd->data_length, XCOPY_HDR_LEN);
+		return TCM_PARAMETER_LIST_LENGTH_ERROR;
+	}
+
+	xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
+	if (!xop)
+		goto err;
+	xop->xop_se_cmd = se_cmd;
+	INIT_WORK(&xop->xop_work, target_xcopy_do_work);
+	if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
+		goto free;
+	return TCM_NO_SENSE;
+
+free:
+	kfree(xop);
+
+err:
+	return TCM_OUT_OF_RESOURCES;
+}
+
+static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
+{
+	unsigned char *p;
+
+	p = transport_kmap_data_sg(se_cmd);
+	if (!p) {
+		pr_err("transport_kmap_data_sg failed in"
+		       " target_rcr_operating_parameters\n");
+		return TCM_OUT_OF_RESOURCES;
+	}
+
+	if (se_cmd->data_length < 54) {
+		pr_err("Receive Copy Results Op Parameters length"
+		       " too small: %u\n", se_cmd->data_length);
+		transport_kunmap_data_sg(se_cmd);
+		return TCM_INVALID_CDB_FIELD;
+	}
+	/*
+	 * Set SNLID=1 (Supports no List ID)
+	 */
+	p[4] = 0x1;
+	/*
+	 * MAXIMUM TARGET DESCRIPTOR COUNT
+	 */
+	put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
+	/*
+	 * MAXIMUM SEGMENT DESCRIPTOR COUNT
+	 */
+	put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
+	/*
+	 * MAXIMUM DESCRIPTOR LIST LENGTH
+	 */
+	put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
+	/*
+	 * MAXIMUM SEGMENT LENGTH
+	 */
+	put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
+	/*
+	 * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
+	 */
+	put_unaligned_be32(0x0, &p[20]);
+	/*
+	 * HELD DATA LIMIT
+	 */
+	put_unaligned_be32(0x0, &p[24]);
+	/*
+	 * MAXIMUM STREAM DEVICE TRANSFER SIZE
+	 */
+	put_unaligned_be32(0x0, &p[28]);
+	/*
+	 * TOTAL CONCURRENT COPIES
+	 */
+	put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
+	/*
+	 * MAXIMUM CONCURRENT COPIES
+	 */
+	p[36] = RCR_OP_MAX_CONCURR_COPIES;
+	/*
+	 * DATA SEGMENT GRANULARITY (log 2)
+	 */
+	p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
+	/*
+	 * INLINE DATA GRANULARITY log 2)
+	 */
+	p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
+	/*
+	 * HELD DATA GRANULARITY
+	 */
+	p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
+	/*
+	 * IMPLEMENTED DESCRIPTOR LIST LENGTH
+	 */
+	p[43] = 0x2;
+	/*
+	 * List of implemented descriptor type codes (ordered)
+	 */
+	p[44] = 0x02; /* Copy Block to Block device */
+	p[45] = 0xe4; /* Identification descriptor target descriptor */
+
+	/*
+	 * AVAILABLE DATA (n-3)
+	 */
+	put_unaligned_be32(42, &p[0]);
+
+	transport_kunmap_data_sg(se_cmd);
+	target_complete_cmd(se_cmd, SAM_STAT_GOOD);
+
+	return TCM_NO_SENSE;
+}
+
+sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
+{
+	unsigned char *cdb = &se_cmd->t_task_cdb[0];
+	int sa = (cdb[1] & 0x1f), list_id = cdb[2];
+	sense_reason_t rc = TCM_NO_SENSE;
+
+	pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
+		" 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
+
+	if (list_id != 0) {
+		pr_err("Receive Copy Results with non zero list identifier"
+		       " not supported\n");
+		return TCM_INVALID_CDB_FIELD;
+	}
+
+	switch (sa) {
+	case RCR_SA_OPERATING_PARAMETERS:
+		rc = target_rcr_operating_parameters(se_cmd);
+		break;
+	case RCR_SA_COPY_STATUS:
+	case RCR_SA_RECEIVE_DATA:
+	case RCR_SA_FAILED_SEGMENT_DETAILS:
+	default:
+		pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
+		return TCM_INVALID_CDB_FIELD;
+	}
+
+	return rc;
+}