Adding upstream version 6.6.15.upstream/6.6.15

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

5 files changed, 4987 insertions, 0 deletions

diff --git a/drivers/scsi/ibmvscsi_tgt/Makefile b/drivers/scsi/ibmvscsi_tgt/Makefile
new file mode 100644
index 0000000000..cc7a8256dc
--- /dev/null
+++ b/drivers/scsi/ibmvscsi_tgt/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_SCSI_IBMVSCSIS)	+= ibmvscsis.o
+
+ibmvscsis-y := libsrp.o ibmvscsi_tgt.o
diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
new file mode 100644
index 0000000000..385f812b87
--- /dev/null
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
@@ -0,0 +1,4076 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ * IBM Virtual SCSI Target Driver
+ * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
+ *			   Santiago Leon (santil@us.ibm.com) IBM Corp.
+ *			   Linda Xie (lxie@us.ibm.com) IBM Corp.
+ *
+ * Copyright (C) 2005-2011 FUJITA Tomonori <tomof@acm.org>
+ * Copyright (C) 2010 Nicholas A. Bellinger <nab@kernel.org>
+ *
+ * Authors: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
+ * Authors: Michael Cyr <mikecyr@linux.vnet.ibm.com>
+ *
+ ****************************************************************************/
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_fabric.h>
+
+#include <asm/hvcall.h>
+#include <asm/vio.h>
+
+#include <scsi/viosrp.h>
+
+#include "ibmvscsi_tgt.h"
+
+#define IBMVSCSIS_VERSION	"v0.2"
+
+#define	INITIAL_SRP_LIMIT	1024
+#define	DEFAULT_MAX_SECTORS	256
+#define MAX_TXU			1024 * 1024
+
+static uint max_vdma_size = MAX_H_COPY_RDMA;
+
+static char system_id[SYS_ID_NAME_LEN] = "";
+static char partition_name[PARTITION_NAMELEN] = "UNKNOWN";
+static uint partition_number = -1;
+
+/* Adapter list and lock to control it */
+static DEFINE_SPINLOCK(ibmvscsis_dev_lock);
+static LIST_HEAD(ibmvscsis_dev_list);
+
+static long ibmvscsis_parse_command(struct scsi_info *vscsi,
+				    struct viosrp_crq *crq);
+
+static void ibmvscsis_adapter_idle(struct scsi_info *vscsi);
+
+static void ibmvscsis_determine_resid(struct se_cmd *se_cmd,
+				      struct srp_rsp *rsp)
+{
+	u32 residual_count = se_cmd->residual_count;
+
+	if (!residual_count)
+		return;
+
+	if (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
+		if (se_cmd->data_direction == DMA_TO_DEVICE) {
+			/* residual data from an underflow write */
+			rsp->flags = SRP_RSP_FLAG_DOUNDER;
+			rsp->data_out_res_cnt = cpu_to_be32(residual_count);
+		} else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
+			/* residual data from an underflow read */
+			rsp->flags = SRP_RSP_FLAG_DIUNDER;
+			rsp->data_in_res_cnt = cpu_to_be32(residual_count);
+		}
+	} else if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
+		if (se_cmd->data_direction == DMA_TO_DEVICE) {
+			/* residual data from an overflow write */
+			rsp->flags = SRP_RSP_FLAG_DOOVER;
+			rsp->data_out_res_cnt = cpu_to_be32(residual_count);
+		} else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
+			/* residual data from an overflow read */
+			rsp->flags = SRP_RSP_FLAG_DIOVER;
+			rsp->data_in_res_cnt = cpu_to_be32(residual_count);
+		}
+	}
+}
+
+/**
+ * connection_broken() - Determine if the connection to the client is good
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * This function attempts to send a ping MAD to the client. If the call to
+ * queue the request returns H_CLOSED then the connection has been broken
+ * and the function returns TRUE.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt or Process environment
+ */
+static bool connection_broken(struct scsi_info *vscsi)
+{
+	struct viosrp_crq *crq;
+	u64 buffer[2] = { 0, 0 };
+	long h_return_code;
+	bool rc = false;
+
+	/* create a PING crq */
+	crq = (struct viosrp_crq *)&buffer;
+	crq->valid = VALID_CMD_RESP_EL;
+	crq->format = MESSAGE_IN_CRQ;
+	crq->status = PING;
+
+	h_return_code = h_send_crq(vscsi->dds.unit_id,
+				   cpu_to_be64(buffer[MSG_HI]),
+				   cpu_to_be64(buffer[MSG_LOW]));
+
+	dev_dbg(&vscsi->dev, "Connection_broken: rc %ld\n", h_return_code);
+
+	if (h_return_code == H_CLOSED)
+		rc = true;
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_unregister_command_q() - Helper Function-Unregister Command Queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * This function calls h_free_q then frees the interrupt bit etc.
+ * It must release the lock before doing so because of the time it can take
+ * for h_free_crq in PHYP
+ * NOTE: * the caller must make sure that state and or flags will prevent
+ *	   interrupt handler from scheduling work.
+ *       * anyone calling this function may need to set the CRQ_CLOSED flag
+ *	   we can't do it here, because we don't have the lock
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process level
+ */
+static long ibmvscsis_unregister_command_q(struct scsi_info *vscsi)
+{
+	long qrc;
+	long rc = ADAPT_SUCCESS;
+	int ticks = 0;
+
+	do {
+		qrc = h_free_crq(vscsi->dds.unit_id);
+		switch (qrc) {
+		case H_SUCCESS:
+			spin_lock_bh(&vscsi->intr_lock);
+			vscsi->flags &= ~PREP_FOR_SUSPEND_FLAGS;
+			spin_unlock_bh(&vscsi->intr_lock);
+			break;
+
+		case H_HARDWARE:
+		case H_PARAMETER:
+			dev_err(&vscsi->dev, "unregister_command_q: error from h_free_crq %ld\n",
+				qrc);
+			rc = ERROR;
+			break;
+
+		case H_BUSY:
+		case H_LONG_BUSY_ORDER_1_MSEC:
+			/* msleep not good for small values */
+			usleep_range(1000, 2000);
+			ticks += 1;
+			break;
+		case H_LONG_BUSY_ORDER_10_MSEC:
+			usleep_range(10000, 20000);
+			ticks += 10;
+			break;
+		case H_LONG_BUSY_ORDER_100_MSEC:
+			msleep(100);
+			ticks += 100;
+			break;
+		case H_LONG_BUSY_ORDER_1_SEC:
+			ssleep(1);
+			ticks += 1000;
+			break;
+		case H_LONG_BUSY_ORDER_10_SEC:
+			ssleep(10);
+			ticks += 10000;
+			break;
+		case H_LONG_BUSY_ORDER_100_SEC:
+			ssleep(100);
+			ticks += 100000;
+			break;
+		default:
+			dev_err(&vscsi->dev, "unregister_command_q: unknown error %ld from h_free_crq\n",
+				qrc);
+			rc = ERROR;
+			break;
+		}
+
+		/*
+		 * dont wait more then 300 seconds
+		 * ticks are in milliseconds more or less
+		 */
+		if (ticks > 300000 && qrc != H_SUCCESS) {
+			rc = ERROR;
+			dev_err(&vscsi->dev, "Excessive wait for h_free_crq\n");
+		}
+	} while (qrc != H_SUCCESS && rc == ADAPT_SUCCESS);
+
+	dev_dbg(&vscsi->dev, "Freeing CRQ: phyp rc %ld, rc %ld\n", qrc, rc);
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_delete_client_info() - Helper function to Delete Client Info
+ * @vscsi:	Pointer to our adapter structure
+ * @client_closed:	True if client closed its queue
+ *
+ * Deletes information specific to the client when the client goes away
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt or Process
+ */
+static void ibmvscsis_delete_client_info(struct scsi_info *vscsi,
+					 bool client_closed)
+{
+	vscsi->client_cap = 0;
+
+	/*
+	 * Some things we don't want to clear if we're closing the queue,
+	 * because some clients don't resend the host handshake when they
+	 * get a transport event.
+	 */
+	if (client_closed)
+		vscsi->client_data.os_type = 0;
+}
+
+/**
+ * ibmvscsis_free_command_q() - Free Command Queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * This function calls unregister_command_q, then clears interrupts and
+ * any pending interrupt acknowledgments associated with the command q.
+ * It also clears memory if there is no error.
+ *
+ * PHYP did not meet the PAPR architecture so that we must give up the
+ * lock. This causes a timing hole regarding state change.  To close the
+ * hole this routine does accounting on any change that occurred during
+ * the time the lock is not held.
+ * NOTE: must give up and then acquire the interrupt lock, the caller must
+ *	 make sure that state and or flags will prevent interrupt handler from
+ *	 scheduling work.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process level, interrupt lock is held
+ */
+static long ibmvscsis_free_command_q(struct scsi_info *vscsi)
+{
+	int bytes;
+	u32 flags_under_lock;
+	u16 state_under_lock;
+	long rc = ADAPT_SUCCESS;
+
+	if (!(vscsi->flags & CRQ_CLOSED)) {
+		vio_disable_interrupts(vscsi->dma_dev);
+
+		state_under_lock = vscsi->new_state;
+		flags_under_lock = vscsi->flags;
+		vscsi->phyp_acr_state = 0;
+		vscsi->phyp_acr_flags = 0;
+
+		spin_unlock_bh(&vscsi->intr_lock);
+		rc = ibmvscsis_unregister_command_q(vscsi);
+		spin_lock_bh(&vscsi->intr_lock);
+
+		if (state_under_lock != vscsi->new_state)
+			vscsi->phyp_acr_state = vscsi->new_state;
+
+		vscsi->phyp_acr_flags = ((~flags_under_lock) & vscsi->flags);
+
+		if (rc == ADAPT_SUCCESS) {
+			bytes = vscsi->cmd_q.size * PAGE_SIZE;
+			memset(vscsi->cmd_q.base_addr, 0, bytes);
+			vscsi->cmd_q.index = 0;
+			vscsi->flags |= CRQ_CLOSED;
+
+			ibmvscsis_delete_client_info(vscsi, false);
+		}
+
+		dev_dbg(&vscsi->dev, "free_command_q: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
+			vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
+			vscsi->phyp_acr_state);
+	}
+	return rc;
+}
+
+/**
+ * ibmvscsis_cmd_q_dequeue() - Get valid Command element
+ * @mask:	Mask to use in case index wraps
+ * @current_index:	Current index into command queue
+ * @base_addr:	Pointer to start of command queue
+ *
+ * Returns a pointer to a valid command element or NULL, if the command
+ * queue is empty
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt environment, interrupt lock held
+ */
+static struct viosrp_crq *ibmvscsis_cmd_q_dequeue(uint mask,
+						  uint *current_index,
+						  struct viosrp_crq *base_addr)
+{
+	struct viosrp_crq *ptr;
+
+	ptr = base_addr + *current_index;
+
+	if (ptr->valid) {
+		*current_index = (*current_index + 1) & mask;
+		dma_rmb();
+	} else {
+		ptr = NULL;
+	}
+
+	return ptr;
+}
+
+/**
+ * ibmvscsis_send_init_message() - send initialize message to the client
+ * @vscsi:	Pointer to our adapter structure
+ * @format:	Which Init Message format to send
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt environment interrupt lock held
+ */
+static long ibmvscsis_send_init_message(struct scsi_info *vscsi, u8 format)
+{
+	struct viosrp_crq *crq;
+	u64 buffer[2] = { 0, 0 };
+	long rc;
+
+	crq = (struct viosrp_crq *)&buffer;
+	crq->valid = VALID_INIT_MSG;
+	crq->format = format;
+	rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
+			cpu_to_be64(buffer[MSG_LOW]));
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_check_init_msg() - Check init message valid
+ * @vscsi:	Pointer to our adapter structure
+ * @format:	Pointer to return format of Init Message, if any.
+ *		Set to UNUSED_FORMAT if no Init Message in queue.
+ *
+ * Checks if an initialize message was queued by the initiatior
+ * after the queue was created and before the interrupt was enabled.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process level only, interrupt lock held
+ */
+static long ibmvscsis_check_init_msg(struct scsi_info *vscsi, uint *format)
+{
+	struct viosrp_crq *crq;
+	long rc = ADAPT_SUCCESS;
+
+	crq = ibmvscsis_cmd_q_dequeue(vscsi->cmd_q.mask, &vscsi->cmd_q.index,
+				      vscsi->cmd_q.base_addr);
+	if (!crq) {
+		*format = (uint)UNUSED_FORMAT;
+	} else if (crq->valid == VALID_INIT_MSG && crq->format == INIT_MSG) {
+		*format = (uint)INIT_MSG;
+		crq->valid = INVALIDATE_CMD_RESP_EL;
+		dma_rmb();
+
+		/*
+		 * the caller has ensured no initialize message was
+		 * sent after the queue was
+		 * created so there should be no other message on the queue.
+		 */
+		crq = ibmvscsis_cmd_q_dequeue(vscsi->cmd_q.mask,
+					      &vscsi->cmd_q.index,
+					      vscsi->cmd_q.base_addr);
+		if (crq) {
+			*format = (uint)(crq->format);
+			rc = ERROR;
+			crq->valid = INVALIDATE_CMD_RESP_EL;
+			dma_rmb();
+		}
+	} else {
+		*format = (uint)(crq->format);
+		rc = ERROR;
+		crq->valid = INVALIDATE_CMD_RESP_EL;
+		dma_rmb();
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_disconnect() - Helper function to disconnect
+ * @work:	Pointer to work_struct, gives access to our adapter structure
+ *
+ * An error has occurred or the driver received a Transport event,
+ * and the driver is requesting that the command queue be de-registered
+ * in a safe manner. If there is no outstanding I/O then we can stop the
+ * queue. If we are restarting the queue it will be reflected in the
+ * the state of the adapter.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process environment
+ */
+static void ibmvscsis_disconnect(struct work_struct *work)
+{
+	struct scsi_info *vscsi = container_of(work, struct scsi_info,
+					       proc_work);
+	u16 new_state;
+	bool wait_idle = false;
+
+	spin_lock_bh(&vscsi->intr_lock);
+	new_state = vscsi->new_state;
+	vscsi->new_state = 0;
+
+	vscsi->flags |= DISCONNECT_SCHEDULED;
+	vscsi->flags &= ~SCHEDULE_DISCONNECT;
+
+	dev_dbg(&vscsi->dev, "disconnect: flags 0x%x, state 0x%hx\n",
+		vscsi->flags, vscsi->state);
+
+	/*
+	 * check which state we are in and see if we
+	 * should transitition to the new state
+	 */
+	switch (vscsi->state) {
+	/* Should never be called while in this state. */
+	case NO_QUEUE:
+	/*
+	 * Can never transition from this state;
+	 * igonore errors and logout.
+	 */
+	case UNCONFIGURING:
+		break;
+
+	/* can transition from this state to UNCONFIGURING */
+	case ERR_DISCONNECT:
+		if (new_state == UNCONFIGURING)
+			vscsi->state = new_state;
+		break;
+
+	/*
+	 * Can transition from this state to unconfiguring
+	 * or err disconnect.
+	 */
+	case ERR_DISCONNECT_RECONNECT:
+		switch (new_state) {
+		case UNCONFIGURING:
+		case ERR_DISCONNECT:
+			vscsi->state = new_state;
+			break;
+
+		case WAIT_IDLE:
+			break;
+		default:
+			break;
+		}
+		break;
+
+	/* can transition from this state to UNCONFIGURING */
+	case ERR_DISCONNECTED:
+		if (new_state == UNCONFIGURING)
+			vscsi->state = new_state;
+		break;
+
+	case WAIT_ENABLED:
+		switch (new_state) {
+		case UNCONFIGURING:
+			vscsi->state = new_state;
+			vscsi->flags |= RESPONSE_Q_DOWN;
+			vscsi->flags &= ~(SCHEDULE_DISCONNECT |
+					  DISCONNECT_SCHEDULED);
+			dma_rmb();
+			if (vscsi->flags & CFG_SLEEPING) {
+				vscsi->flags &= ~CFG_SLEEPING;
+				complete(&vscsi->unconfig);
+			}
+			break;
+
+		/* should never happen */
+		case ERR_DISCONNECT:
+		case ERR_DISCONNECT_RECONNECT:
+		case WAIT_IDLE:
+			dev_err(&vscsi->dev, "disconnect: invalid state %d for WAIT_IDLE\n",
+				vscsi->state);
+			break;
+		}
+		break;
+
+	case WAIT_IDLE:
+		switch (new_state) {
+		case UNCONFIGURING:
+			vscsi->flags |= RESPONSE_Q_DOWN;
+			vscsi->state = new_state;
+			vscsi->flags &= ~(SCHEDULE_DISCONNECT |
+					  DISCONNECT_SCHEDULED);
+			ibmvscsis_free_command_q(vscsi);
+			break;
+		case ERR_DISCONNECT:
+		case ERR_DISCONNECT_RECONNECT:
+			vscsi->state = new_state;
+			break;
+		}
+		break;
+
+	/*
+	 * Initiator has not done a successful srp login
+	 * or has done a successful srp logout ( adapter was not
+	 * busy). In the first case there can be responses queued
+	 * waiting for space on the initiators response queue (MAD)
+	 * The second case the adapter is idle. Assume the worse case,
+	 * i.e. the second case.
+	 */
+	case WAIT_CONNECTION:
+	case CONNECTED:
+	case SRP_PROCESSING:
+		wait_idle = true;
+		vscsi->state = new_state;
+		break;
+
+	/* can transition from this state to UNCONFIGURING */
+	case UNDEFINED:
+		if (new_state == UNCONFIGURING)
+			vscsi->state = new_state;
+		break;
+	default:
+		break;
+	}
+
+	if (wait_idle) {
+		dev_dbg(&vscsi->dev, "disconnect start wait, active %d, sched %d\n",
+			(int)list_empty(&vscsi->active_q),
+			(int)list_empty(&vscsi->schedule_q));
+		if (!list_empty(&vscsi->active_q) ||
+		    !list_empty(&vscsi->schedule_q)) {
+			vscsi->flags |= WAIT_FOR_IDLE;
+			dev_dbg(&vscsi->dev, "disconnect flags 0x%x\n",
+				vscsi->flags);
+			/*
+			 * This routine is can not be called with the interrupt
+			 * lock held.
+			 */
+			spin_unlock_bh(&vscsi->intr_lock);
+			wait_for_completion(&vscsi->wait_idle);
+			spin_lock_bh(&vscsi->intr_lock);
+		}
+		dev_dbg(&vscsi->dev, "disconnect stop wait\n");
+
+		ibmvscsis_adapter_idle(vscsi);
+	}
+
+	spin_unlock_bh(&vscsi->intr_lock);
+}
+
+/**
+ * ibmvscsis_post_disconnect() - Schedule the disconnect
+ * @vscsi:	Pointer to our adapter structure
+ * @new_state:	State to move to after disconnecting
+ * @flag_bits:	Flags to turn on in adapter structure
+ *
+ * If it's already been scheduled, then see if we need to "upgrade"
+ * the new state (if the one passed in is more "severe" than the
+ * previous one).
+ *
+ * PRECONDITION:
+ *	interrupt lock is held
+ */
+static void ibmvscsis_post_disconnect(struct scsi_info *vscsi, uint new_state,
+				      uint flag_bits)
+{
+	uint state;
+
+	/* check the validity of the new state */
+	switch (new_state) {
+	case UNCONFIGURING:
+	case ERR_DISCONNECT:
+	case ERR_DISCONNECT_RECONNECT:
+	case WAIT_IDLE:
+		break;
+
+	default:
+		dev_err(&vscsi->dev, "post_disconnect: Invalid new state %d\n",
+			new_state);
+		return;
+	}
+
+	vscsi->flags |= flag_bits;
+
+	dev_dbg(&vscsi->dev, "post_disconnect: new_state 0x%x, flag_bits 0x%x, vscsi->flags 0x%x, state %hx\n",
+		new_state, flag_bits, vscsi->flags, vscsi->state);
+
+	if (!(vscsi->flags & (DISCONNECT_SCHEDULED | SCHEDULE_DISCONNECT))) {
+		vscsi->flags |= SCHEDULE_DISCONNECT;
+		vscsi->new_state = new_state;
+
+		INIT_WORK(&vscsi->proc_work, ibmvscsis_disconnect);
+		(void)queue_work(vscsi->work_q, &vscsi->proc_work);
+	} else {
+		if (vscsi->new_state)
+			state = vscsi->new_state;
+		else
+			state = vscsi->state;
+
+		switch (state) {
+		case NO_QUEUE:
+		case UNCONFIGURING:
+			break;
+
+		case ERR_DISCONNECTED:
+		case ERR_DISCONNECT:
+		case UNDEFINED:
+			if (new_state == UNCONFIGURING)
+				vscsi->new_state = new_state;
+			break;
+
+		case ERR_DISCONNECT_RECONNECT:
+			switch (new_state) {
+			case UNCONFIGURING:
+			case ERR_DISCONNECT:
+				vscsi->new_state = new_state;
+				break;
+			default:
+				break;
+			}
+			break;
+
+		case WAIT_ENABLED:
+		case WAIT_IDLE:
+		case WAIT_CONNECTION:
+		case CONNECTED:
+		case SRP_PROCESSING:
+			vscsi->new_state = new_state;
+			break;
+
+		default:
+			break;
+		}
+	}
+
+	dev_dbg(&vscsi->dev, "Leaving post_disconnect: flags 0x%x, new_state 0x%x\n",
+		vscsi->flags, vscsi->new_state);
+}
+
+/**
+ * ibmvscsis_handle_init_compl_msg() - Respond to an Init Complete Message
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Must be called with interrupt lock held.
+ */
+static long ibmvscsis_handle_init_compl_msg(struct scsi_info *vscsi)
+{
+	long rc = ADAPT_SUCCESS;
+
+	switch (vscsi->state) {
+	case NO_QUEUE:
+	case ERR_DISCONNECT:
+	case ERR_DISCONNECT_RECONNECT:
+	case ERR_DISCONNECTED:
+	case UNCONFIGURING:
+	case UNDEFINED:
+		rc = ERROR;
+		break;
+
+	case WAIT_CONNECTION:
+		vscsi->state = CONNECTED;
+		break;
+
+	case WAIT_IDLE:
+	case SRP_PROCESSING:
+	case CONNECTED:
+	case WAIT_ENABLED:
+	default:
+		rc = ERROR;
+		dev_err(&vscsi->dev, "init_msg: invalid state %d to get init compl msg\n",
+			vscsi->state);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_handle_init_msg() - Respond to an Init Message
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Must be called with interrupt lock held.
+ */
+static long ibmvscsis_handle_init_msg(struct scsi_info *vscsi)
+{
+	long rc = ADAPT_SUCCESS;
+
+	switch (vscsi->state) {
+	case WAIT_CONNECTION:
+		rc = ibmvscsis_send_init_message(vscsi, INIT_COMPLETE_MSG);
+		switch (rc) {
+		case H_SUCCESS:
+			vscsi->state = CONNECTED;
+			break;
+
+		case H_PARAMETER:
+			dev_err(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
+				rc);
+			ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
+			break;
+
+		case H_DROPPED:
+			dev_err(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
+				rc);
+			rc = ERROR;
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT, 0);
+			break;
+
+		case H_CLOSED:
+			dev_warn(&vscsi->dev, "init_msg: failed to send, rc %ld\n",
+				 rc);
+			rc = 0;
+			break;
+		}
+		break;
+
+	case UNDEFINED:
+		rc = ERROR;
+		break;
+
+	case UNCONFIGURING:
+		break;
+
+	case WAIT_ENABLED:
+	case CONNECTED:
+	case SRP_PROCESSING:
+	case WAIT_IDLE:
+	case NO_QUEUE:
+	case ERR_DISCONNECT:
+	case ERR_DISCONNECT_RECONNECT:
+	case ERR_DISCONNECTED:
+	default:
+		rc = ERROR;
+		dev_err(&vscsi->dev, "init_msg: invalid state %d to get init msg\n",
+			vscsi->state);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_init_msg() - Respond to an init message
+ * @vscsi:	Pointer to our adapter structure
+ * @crq:	Pointer to CRQ element containing the Init Message
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_init_msg(struct scsi_info *vscsi, struct viosrp_crq *crq)
+{
+	long rc = ADAPT_SUCCESS;
+
+	dev_dbg(&vscsi->dev, "init_msg: state 0x%hx\n", vscsi->state);
+
+	rc = h_vioctl(vscsi->dds.unit_id, H_GET_PARTNER_INFO,
+		      (u64)vscsi->map_ioba | ((u64)PAGE_SIZE << 32), 0, 0, 0,
+		      0);
+	if (rc == H_SUCCESS) {
+		vscsi->client_data.partition_number =
+			be64_to_cpu(*(u64 *)vscsi->map_buf);
+		dev_dbg(&vscsi->dev, "init_msg, part num %d\n",
+			vscsi->client_data.partition_number);
+	} else {
+		dev_dbg(&vscsi->dev, "init_msg h_vioctl rc %ld\n", rc);
+		rc = ADAPT_SUCCESS;
+	}
+
+	if (crq->format == INIT_MSG) {
+		rc = ibmvscsis_handle_init_msg(vscsi);
+	} else if (crq->format == INIT_COMPLETE_MSG) {
+		rc = ibmvscsis_handle_init_compl_msg(vscsi);
+	} else {
+		rc = ERROR;
+		dev_err(&vscsi->dev, "init_msg: invalid format %d\n",
+			(uint)crq->format);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_establish_new_q() - Establish new CRQ queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Must be called with interrupt lock held.
+ */
+static long ibmvscsis_establish_new_q(struct scsi_info *vscsi)
+{
+	long rc = ADAPT_SUCCESS;
+	uint format;
+
+	rc = h_vioctl(vscsi->dds.unit_id, H_ENABLE_PREPARE_FOR_SUSPEND, 30000,
+		      0, 0, 0, 0);
+	if (rc == H_SUCCESS)
+		vscsi->flags |= PREP_FOR_SUSPEND_ENABLED;
+	else if (rc != H_NOT_FOUND)
+		dev_err(&vscsi->dev, "Error from Enable Prepare for Suspend: %ld\n",
+			rc);
+
+	vscsi->flags &= PRESERVE_FLAG_FIELDS;
+	vscsi->rsp_q_timer.timer_pops = 0;
+	vscsi->debit = 0;
+	vscsi->credit = 0;
+
+	rc = vio_enable_interrupts(vscsi->dma_dev);
+	if (rc) {
+		dev_warn(&vscsi->dev, "establish_new_q: failed to enable interrupts, rc %ld\n",
+			 rc);
+		return rc;
+	}
+
+	rc = ibmvscsis_check_init_msg(vscsi, &format);
+	if (rc) {
+		dev_err(&vscsi->dev, "establish_new_q: check_init_msg failed, rc %ld\n",
+			rc);
+		return rc;
+	}
+
+	if (format == UNUSED_FORMAT) {
+		rc = ibmvscsis_send_init_message(vscsi, INIT_MSG);
+		switch (rc) {
+		case H_SUCCESS:
+		case H_DROPPED:
+		case H_CLOSED:
+			rc = ADAPT_SUCCESS;
+			break;
+
+		case H_PARAMETER:
+		case H_HARDWARE:
+			break;
+
+		default:
+			vscsi->state = UNDEFINED;
+			rc = H_HARDWARE;
+			break;
+		}
+	} else if (format == INIT_MSG) {
+		rc = ibmvscsis_handle_init_msg(vscsi);
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_reset_queue() - Reset CRQ Queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * This function calls h_free_q and then calls h_reg_q and does all
+ * of the bookkeeping to get us back to where we can communicate.
+ *
+ * Actually, we don't always call h_free_crq.  A problem was discovered
+ * where one partition would close and reopen his queue, which would
+ * cause his partner to get a transport event, which would cause him to
+ * close and reopen his queue, which would cause the original partition
+ * to get a transport event, etc., etc.  To prevent this, we don't
+ * actually close our queue if the client initiated the reset, (i.e.
+ * either we got a transport event or we have detected that the client's
+ * queue is gone)
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process environment, called with interrupt lock held
+ */
+static void ibmvscsis_reset_queue(struct scsi_info *vscsi)
+{
+	int bytes;
+	long rc = ADAPT_SUCCESS;
+
+	dev_dbg(&vscsi->dev, "reset_queue: flags 0x%x\n", vscsi->flags);
+
+	/* don't reset, the client did it for us */
+	if (vscsi->flags & (CLIENT_FAILED | TRANS_EVENT)) {
+		vscsi->flags &= PRESERVE_FLAG_FIELDS;
+		vscsi->rsp_q_timer.timer_pops = 0;
+		vscsi->debit = 0;
+		vscsi->credit = 0;
+		vscsi->state = WAIT_CONNECTION;
+		vio_enable_interrupts(vscsi->dma_dev);
+	} else {
+		rc = ibmvscsis_free_command_q(vscsi);
+		if (rc == ADAPT_SUCCESS) {
+			vscsi->state = WAIT_CONNECTION;
+
+			bytes = vscsi->cmd_q.size * PAGE_SIZE;
+			rc = h_reg_crq(vscsi->dds.unit_id,
+				       vscsi->cmd_q.crq_token, bytes);
+			if (rc == H_CLOSED || rc == H_SUCCESS) {
+				rc = ibmvscsis_establish_new_q(vscsi);
+			}
+
+			if (rc != ADAPT_SUCCESS) {
+				dev_dbg(&vscsi->dev, "reset_queue: reg_crq rc %ld\n",
+					rc);
+
+				vscsi->state = ERR_DISCONNECTED;
+				vscsi->flags |= RESPONSE_Q_DOWN;
+				ibmvscsis_free_command_q(vscsi);
+			}
+		} else {
+			vscsi->state = ERR_DISCONNECTED;
+			vscsi->flags |= RESPONSE_Q_DOWN;
+		}
+	}
+}
+
+/**
+ * ibmvscsis_free_cmd_resources() - Free command resources
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Command which is not longer in use
+ *
+ * Must be called with interrupt lock held.
+ */
+static void ibmvscsis_free_cmd_resources(struct scsi_info *vscsi,
+					 struct ibmvscsis_cmd *cmd)
+{
+	struct iu_entry *iue = cmd->iue;
+
+	switch (cmd->type) {
+	case TASK_MANAGEMENT:
+	case SCSI_CDB:
+		/*
+		 * When the queue goes down this value is cleared, so it
+		 * cannot be cleared in this general purpose function.
+		 */
+		if (vscsi->debit)
+			vscsi->debit -= 1;
+		break;
+	case ADAPTER_MAD:
+		vscsi->flags &= ~PROCESSING_MAD;
+		break;
+	case UNSET_TYPE:
+		break;
+	default:
+		dev_err(&vscsi->dev, "free_cmd_resources unknown type %d\n",
+			cmd->type);
+		break;
+	}
+
+	cmd->iue = NULL;
+	list_add_tail(&cmd->list, &vscsi->free_cmd);
+	srp_iu_put(iue);
+
+	if (list_empty(&vscsi->active_q) && list_empty(&vscsi->schedule_q) &&
+	    list_empty(&vscsi->waiting_rsp) && (vscsi->flags & WAIT_FOR_IDLE)) {
+		vscsi->flags &= ~WAIT_FOR_IDLE;
+		complete(&vscsi->wait_idle);
+	}
+}
+
+/**
+ * ibmvscsis_ready_for_suspend() - Helper function to call VIOCTL
+ * @vscsi:	Pointer to our adapter structure
+ * @idle:	Indicates whether we were called from adapter_idle.  This
+ *		is important to know if we need to do a disconnect, since if
+ *		we're called from adapter_idle, we're still processing the
+ *		current disconnect, so we can't just call post_disconnect.
+ *
+ * This function is called when the adapter is idle when phyp has sent
+ * us a Prepare for Suspend Transport Event.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process or interrupt environment called with interrupt lock held
+ */
+static long ibmvscsis_ready_for_suspend(struct scsi_info *vscsi, bool idle)
+{
+	long rc = 0;
+	struct viosrp_crq *crq;
+
+	/* See if there is a Resume event in the queue */
+	crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
+
+	dev_dbg(&vscsi->dev, "ready_suspend: flags 0x%x, state 0x%hx crq_valid:%x\n",
+		vscsi->flags, vscsi->state, (int)crq->valid);
+
+	if (!(vscsi->flags & PREP_FOR_SUSPEND_ABORTED) && !(crq->valid)) {
+		rc = h_vioctl(vscsi->dds.unit_id, H_READY_FOR_SUSPEND, 0, 0, 0,
+			      0, 0);
+		if (rc) {
+			dev_err(&vscsi->dev, "Ready for Suspend Vioctl failed: %ld\n",
+				rc);
+			rc = 0;
+		}
+	} else if (((vscsi->flags & PREP_FOR_SUSPEND_OVERWRITE) &&
+		    (vscsi->flags & PREP_FOR_SUSPEND_ABORTED)) ||
+		   ((crq->valid) && ((crq->valid != VALID_TRANS_EVENT) ||
+				     (crq->format != RESUME_FROM_SUSP)))) {
+		if (idle) {
+			vscsi->state = ERR_DISCONNECT_RECONNECT;
+			ibmvscsis_reset_queue(vscsi);
+			rc = -1;
+		} else if (vscsi->state == CONNECTED) {
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT, 0);
+		}
+
+		vscsi->flags &= ~PREP_FOR_SUSPEND_OVERWRITE;
+
+		if ((crq->valid) && ((crq->valid != VALID_TRANS_EVENT) ||
+				     (crq->format != RESUME_FROM_SUSP)))
+			dev_err(&vscsi->dev, "Invalid element in CRQ after Prepare for Suspend");
+	}
+
+	vscsi->flags &= ~(PREP_FOR_SUSPEND_PENDING | PREP_FOR_SUSPEND_ABORTED);
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_trans_event() - Handle a Transport Event
+ * @vscsi:	Pointer to our adapter structure
+ * @crq:	Pointer to CRQ entry containing the Transport Event
+ *
+ * Do the logic to close the I_T nexus.  This function may not
+ * behave to specification.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_trans_event(struct scsi_info *vscsi,
+				  struct viosrp_crq *crq)
+{
+	long rc = ADAPT_SUCCESS;
+
+	dev_dbg(&vscsi->dev, "trans_event: format %d, flags 0x%x, state 0x%hx\n",
+		(int)crq->format, vscsi->flags, vscsi->state);
+
+	switch (crq->format) {
+	case MIGRATED:
+	case PARTNER_FAILED:
+	case PARTNER_DEREGISTER:
+		ibmvscsis_delete_client_info(vscsi, true);
+		if (crq->format == MIGRATED)
+			vscsi->flags &= ~PREP_FOR_SUSPEND_OVERWRITE;
+		switch (vscsi->state) {
+		case NO_QUEUE:
+		case ERR_DISCONNECTED:
+		case UNDEFINED:
+			break;
+
+		case UNCONFIGURING:
+			vscsi->flags |= (RESPONSE_Q_DOWN | TRANS_EVENT);
+			break;
+
+		case WAIT_ENABLED:
+			break;
+
+		case WAIT_CONNECTION:
+			break;
+
+		case CONNECTED:
+			ibmvscsis_post_disconnect(vscsi, WAIT_IDLE,
+						  (RESPONSE_Q_DOWN |
+						   TRANS_EVENT));
+			break;
+
+		case SRP_PROCESSING:
+			if ((vscsi->debit > 0) ||
+			    !list_empty(&vscsi->schedule_q) ||
+			    !list_empty(&vscsi->waiting_rsp) ||
+			    !list_empty(&vscsi->active_q)) {
+				dev_dbg(&vscsi->dev, "debit %d, sched %d, wait %d, active %d\n",
+					vscsi->debit,
+					(int)list_empty(&vscsi->schedule_q),
+					(int)list_empty(&vscsi->waiting_rsp),
+					(int)list_empty(&vscsi->active_q));
+				dev_warn(&vscsi->dev, "connection lost with outstanding work\n");
+			} else {
+				dev_dbg(&vscsi->dev, "trans_event: SRP Processing, but no outstanding work\n");
+			}
+
+			ibmvscsis_post_disconnect(vscsi, WAIT_IDLE,
+						  (RESPONSE_Q_DOWN |
+						   TRANS_EVENT));
+			break;
+
+		case ERR_DISCONNECT:
+		case ERR_DISCONNECT_RECONNECT:
+		case WAIT_IDLE:
+			vscsi->flags |= (RESPONSE_Q_DOWN | TRANS_EVENT);
+			break;
+		}
+		break;
+
+	case PREPARE_FOR_SUSPEND:
+		dev_dbg(&vscsi->dev, "Prep for Suspend, crq status = 0x%x\n",
+			(int)crq->status);
+		switch (vscsi->state) {
+		case ERR_DISCONNECTED:
+		case WAIT_CONNECTION:
+		case CONNECTED:
+			ibmvscsis_ready_for_suspend(vscsi, false);
+			break;
+		case SRP_PROCESSING:
+			vscsi->resume_state = vscsi->state;
+			vscsi->flags |= PREP_FOR_SUSPEND_PENDING;
+			if (crq->status == CRQ_ENTRY_OVERWRITTEN)
+				vscsi->flags |= PREP_FOR_SUSPEND_OVERWRITE;
+			ibmvscsis_post_disconnect(vscsi, WAIT_IDLE, 0);
+			break;
+		case NO_QUEUE:
+		case UNDEFINED:
+		case UNCONFIGURING:
+		case WAIT_ENABLED:
+		case ERR_DISCONNECT:
+		case ERR_DISCONNECT_RECONNECT:
+		case WAIT_IDLE:
+			dev_err(&vscsi->dev, "Invalid state for Prepare for Suspend Trans Event: 0x%x\n",
+				vscsi->state);
+			break;
+		}
+		break;
+
+	case RESUME_FROM_SUSP:
+		dev_dbg(&vscsi->dev, "Resume from Suspend, crq status = 0x%x\n",
+			(int)crq->status);
+		if (vscsi->flags & PREP_FOR_SUSPEND_PENDING) {
+			vscsi->flags |= PREP_FOR_SUSPEND_ABORTED;
+		} else {
+			if ((crq->status == CRQ_ENTRY_OVERWRITTEN) ||
+			    (vscsi->flags & PREP_FOR_SUSPEND_OVERWRITE)) {
+				ibmvscsis_post_disconnect(vscsi,
+							  ERR_DISCONNECT_RECONNECT,
+							  0);
+				vscsi->flags &= ~PREP_FOR_SUSPEND_OVERWRITE;
+			}
+		}
+		break;
+
+	default:
+		rc = ERROR;
+		dev_err(&vscsi->dev, "trans_event: invalid format %d\n",
+			(uint)crq->format);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT,
+					  RESPONSE_Q_DOWN);
+		break;
+	}
+
+	rc = vscsi->flags & SCHEDULE_DISCONNECT;
+
+	dev_dbg(&vscsi->dev, "Leaving trans_event: flags 0x%x, state 0x%hx, rc %ld\n",
+		vscsi->flags, vscsi->state, rc);
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_poll_cmd_q() - Poll Command Queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Called to handle command elements that may have arrived while
+ * interrupts were disabled.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	intr_lock must be held
+ */
+static void ibmvscsis_poll_cmd_q(struct scsi_info *vscsi)
+{
+	struct viosrp_crq *crq;
+	long rc;
+	bool ack = true;
+	volatile u8 valid;
+
+	dev_dbg(&vscsi->dev, "poll_cmd_q: flags 0x%x, state 0x%hx, q index %ud\n",
+		vscsi->flags, vscsi->state, vscsi->cmd_q.index);
+
+	rc = vscsi->flags & SCHEDULE_DISCONNECT;
+	crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
+	valid = crq->valid;
+	dma_rmb();
+
+	while (valid) {
+poll_work:
+		vscsi->cmd_q.index =
+			(vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
+
+		if (!rc) {
+			rc = ibmvscsis_parse_command(vscsi, crq);
+		} else {
+			if ((uint)crq->valid == VALID_TRANS_EVENT) {
+				/*
+				 * must service the transport layer events even
+				 * in an error state, dont break out until all
+				 * the consecutive transport events have been
+				 * processed
+				 */
+				rc = ibmvscsis_trans_event(vscsi, crq);
+			} else if (vscsi->flags & TRANS_EVENT) {
+				/*
+				 * if a tranport event has occurred leave
+				 * everything but transport events on the queue
+				 */
+				dev_dbg(&vscsi->dev, "poll_cmd_q, ignoring\n");
+
+				/*
+				 * need to decrement the queue index so we can
+				 * look at the elment again
+				 */
+				if (vscsi->cmd_q.index)
+					vscsi->cmd_q.index -= 1;
+				else
+					/*
+					 * index is at 0 it just wrapped.
+					 * have it index last element in q
+					 */
+					vscsi->cmd_q.index = vscsi->cmd_q.mask;
+				break;
+			}
+		}
+
+		crq->valid = INVALIDATE_CMD_RESP_EL;
+
+		crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
+		valid = crq->valid;
+		dma_rmb();
+	}
+
+	if (!rc) {
+		if (ack) {
+			vio_enable_interrupts(vscsi->dma_dev);
+			ack = false;
+			dev_dbg(&vscsi->dev, "poll_cmd_q, reenabling interrupts\n");
+		}
+		valid = crq->valid;
+		dma_rmb();
+		if (valid)
+			goto poll_work;
+	}
+
+	dev_dbg(&vscsi->dev, "Leaving poll_cmd_q: rc %ld\n", rc);
+}
+
+/**
+ * ibmvscsis_free_cmd_qs() - Free elements in queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Free all of the elements on all queues that are waiting for
+ * whatever reason.
+ *
+ * PRECONDITION:
+ *	Called with interrupt lock held
+ */
+static void ibmvscsis_free_cmd_qs(struct scsi_info *vscsi)
+{
+	struct ibmvscsis_cmd *cmd, *nxt;
+
+	dev_dbg(&vscsi->dev, "free_cmd_qs: waiting_rsp empty %d, timer starter %d\n",
+		(int)list_empty(&vscsi->waiting_rsp),
+		vscsi->rsp_q_timer.started);
+
+	list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp, list) {
+		list_del(&cmd->list);
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+	}
+}
+
+/**
+ * ibmvscsis_get_free_cmd() - Get free command from list
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Must be called with interrupt lock held.
+ */
+static struct ibmvscsis_cmd *ibmvscsis_get_free_cmd(struct scsi_info *vscsi)
+{
+	struct ibmvscsis_cmd *cmd = NULL;
+	struct iu_entry *iue;
+
+	iue = srp_iu_get(&vscsi->target);
+	if (iue) {
+		cmd = list_first_entry_or_null(&vscsi->free_cmd,
+					       struct ibmvscsis_cmd, list);
+		if (cmd) {
+			if (cmd->abort_cmd)
+				cmd->abort_cmd = NULL;
+			cmd->flags &= ~(DELAY_SEND);
+			list_del(&cmd->list);
+			cmd->iue = iue;
+			cmd->type = UNSET_TYPE;
+			memset(&cmd->se_cmd, 0, sizeof(cmd->se_cmd));
+		} else {
+			srp_iu_put(iue);
+		}
+	}
+
+	return cmd;
+}
+
+/**
+ * ibmvscsis_adapter_idle() - Helper function to handle idle adapter
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * This function is called when the adapter is idle when the driver
+ * is attempting to clear an error condition.
+ * The adapter is considered busy if any of its cmd queues
+ * are non-empty. This function can be invoked
+ * from the off level disconnect function.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process environment called with interrupt lock held
+ */
+static void ibmvscsis_adapter_idle(struct scsi_info *vscsi)
+{
+	int free_qs = false;
+	long rc = 0;
+
+	dev_dbg(&vscsi->dev, "adapter_idle: flags 0x%x, state 0x%hx\n",
+		vscsi->flags, vscsi->state);
+
+	/* Only need to free qs if we're disconnecting from client */
+	if (vscsi->state != WAIT_CONNECTION || vscsi->flags & TRANS_EVENT)
+		free_qs = true;
+
+	switch (vscsi->state) {
+	case UNCONFIGURING:
+		ibmvscsis_free_command_q(vscsi);
+		dma_rmb();
+		isync();
+		if (vscsi->flags & CFG_SLEEPING) {
+			vscsi->flags &= ~CFG_SLEEPING;
+			complete(&vscsi->unconfig);
+		}
+		break;
+	case ERR_DISCONNECT_RECONNECT:
+		ibmvscsis_reset_queue(vscsi);
+		dev_dbg(&vscsi->dev, "adapter_idle, disc_rec: flags 0x%x\n",
+			vscsi->flags);
+		break;
+
+	case ERR_DISCONNECT:
+		ibmvscsis_free_command_q(vscsi);
+		vscsi->flags &= ~(SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED);
+		vscsi->flags |= RESPONSE_Q_DOWN;
+		if (vscsi->tport.enabled)
+			vscsi->state = ERR_DISCONNECTED;
+		else
+			vscsi->state = WAIT_ENABLED;
+		dev_dbg(&vscsi->dev, "adapter_idle, disc: flags 0x%x, state 0x%hx\n",
+			vscsi->flags, vscsi->state);
+		break;
+
+	case WAIT_IDLE:
+		vscsi->rsp_q_timer.timer_pops = 0;
+		vscsi->debit = 0;
+		vscsi->credit = 0;
+		if (vscsi->flags & PREP_FOR_SUSPEND_PENDING) {
+			vscsi->state = vscsi->resume_state;
+			vscsi->resume_state = 0;
+			rc = ibmvscsis_ready_for_suspend(vscsi, true);
+			vscsi->flags &= ~DISCONNECT_SCHEDULED;
+			if (rc)
+				break;
+		} else if (vscsi->flags & TRANS_EVENT) {
+			vscsi->state = WAIT_CONNECTION;
+			vscsi->flags &= PRESERVE_FLAG_FIELDS;
+		} else {
+			vscsi->state = CONNECTED;
+			vscsi->flags &= ~DISCONNECT_SCHEDULED;
+		}
+
+		dev_dbg(&vscsi->dev, "adapter_idle, wait: flags 0x%x, state 0x%hx\n",
+			vscsi->flags, vscsi->state);
+		ibmvscsis_poll_cmd_q(vscsi);
+		break;
+
+	case ERR_DISCONNECTED:
+		vscsi->flags &= ~DISCONNECT_SCHEDULED;
+		dev_dbg(&vscsi->dev, "adapter_idle, disconnected: flags 0x%x, state 0x%hx\n",
+			vscsi->flags, vscsi->state);
+		break;
+
+	default:
+		dev_err(&vscsi->dev, "adapter_idle: in invalid state %d\n",
+			vscsi->state);
+		break;
+	}
+
+	if (free_qs)
+		ibmvscsis_free_cmd_qs(vscsi);
+
+	/*
+	 * There is a timing window where we could lose a disconnect request.
+	 * The known path to this window occurs during the DISCONNECT_RECONNECT
+	 * case above: reset_queue calls free_command_q, which will release the
+	 * interrupt lock.  During that time, a new post_disconnect call can be
+	 * made with a "more severe" state (DISCONNECT or UNCONFIGURING).
+	 * Because the DISCONNECT_SCHEDULED flag is already set, post_disconnect
+	 * will only set the new_state.  Now free_command_q reacquires the intr
+	 * lock and clears the DISCONNECT_SCHEDULED flag (using PRESERVE_FLAG_
+	 * FIELDS), and the disconnect is lost.  This is particularly bad when
+	 * the new disconnect was for UNCONFIGURING, since the unconfigure hangs
+	 * forever.
+	 * Fix is that free command queue sets acr state and acr flags if there
+	 * is a change under the lock
+	 * note free command queue writes to this state it clears it
+	 * before releasing the lock, different drivers call the free command
+	 * queue different times so dont initialize above
+	 */
+	if (vscsi->phyp_acr_state != 0)	{
+		/*
+		 * set any bits in flags that may have been cleared by
+		 * a call to free command queue in switch statement
+		 * or reset queue
+		 */
+		vscsi->flags |= vscsi->phyp_acr_flags;
+		ibmvscsis_post_disconnect(vscsi, vscsi->phyp_acr_state, 0);
+		vscsi->phyp_acr_state = 0;
+		vscsi->phyp_acr_flags = 0;
+
+		dev_dbg(&vscsi->dev, "adapter_idle: flags 0x%x, state 0x%hx, acr_flags 0x%x, acr_state 0x%hx\n",
+			vscsi->flags, vscsi->state, vscsi->phyp_acr_flags,
+			vscsi->phyp_acr_state);
+	}
+
+	dev_dbg(&vscsi->dev, "Leaving adapter_idle: flags 0x%x, state 0x%hx, new_state 0x%x\n",
+		vscsi->flags, vscsi->state, vscsi->new_state);
+}
+
+/**
+ * ibmvscsis_copy_crq_packet() - Copy CRQ Packet
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Pointer to command element to use to process the request
+ * @crq:	Pointer to CRQ entry containing the request
+ *
+ * Copy the srp information unit from the hosted
+ * partition using remote dma
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_copy_crq_packet(struct scsi_info *vscsi,
+				      struct ibmvscsis_cmd *cmd,
+				      struct viosrp_crq *crq)
+{
+	struct iu_entry *iue = cmd->iue;
+	long rc = 0;
+	u16 len;
+
+	len = be16_to_cpu(crq->IU_length);
+	if ((len > SRP_MAX_IU_LEN) || (len == 0)) {
+		dev_err(&vscsi->dev, "copy_crq: Invalid len %d passed", len);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		return SRP_VIOLATION;
+	}
+
+	rc = h_copy_rdma(len, vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(crq->IU_data_ptr),
+			 vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma);
+
+	switch (rc) {
+	case H_SUCCESS:
+		cmd->init_time = mftb();
+		iue->remote_token = crq->IU_data_ptr;
+		iue->iu_len = len;
+		dev_dbg(&vscsi->dev, "copy_crq: ioba 0x%llx, init_time 0x%llx\n",
+			be64_to_cpu(crq->IU_data_ptr), cmd->init_time);
+		break;
+	case H_PERMISSION:
+		if (connection_broken(vscsi))
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT,
+						  (RESPONSE_Q_DOWN |
+						   CLIENT_FAILED));
+		else
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT, 0);
+
+		dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
+			rc);
+		break;
+	case H_DEST_PARM:
+	case H_SOURCE_PARM:
+	default:
+		dev_err(&vscsi->dev, "copy_crq: h_copy_rdma failed, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_adapter_info - Service an Adapter Info MAnagement Data gram
+ * @vscsi:	Pointer to our adapter structure
+ * @iue:	Information Unit containing the Adapter Info MAD request
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt adapter lock is held
+ */
+static long ibmvscsis_adapter_info(struct scsi_info *vscsi,
+				   struct iu_entry *iue)
+{
+	struct viosrp_adapter_info *mad = &vio_iu(iue)->mad.adapter_info;
+	struct mad_adapter_info_data *info;
+	uint flag_bits = 0;
+	dma_addr_t token;
+	long rc;
+
+	mad->common.status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
+
+	if (be16_to_cpu(mad->common.length) > sizeof(*info)) {
+		mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
+		return 0;
+	}
+
+	info = dma_alloc_coherent(&vscsi->dma_dev->dev, sizeof(*info), &token,
+				  GFP_ATOMIC);
+	if (!info) {
+		dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
+			iue->target);
+		mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
+		return 0;
+	}
+
+	/* Get remote info */
+	rc = h_copy_rdma(be16_to_cpu(mad->common.length),
+			 vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(mad->buffer),
+			 vscsi->dds.window[LOCAL].liobn, token);
+
+	if (rc != H_SUCCESS) {
+		if (rc == H_PERMISSION) {
+			if (connection_broken(vscsi))
+				flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
+		}
+		dev_warn(&vscsi->dev, "adapter_info: h_copy_rdma from client failed, rc %ld\n",
+			 rc);
+		dev_dbg(&vscsi->dev, "adapter_info: ioba 0x%llx, flags 0x%x, flag_bits 0x%x\n",
+			be64_to_cpu(mad->buffer), vscsi->flags, flag_bits);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
+					  flag_bits);
+		goto free_dma;
+	}
+
+	/*
+	 * Copy client info, but ignore partition number, which we
+	 * already got from phyp - unless we failed to get it from
+	 * phyp (e.g. if we're running on a p5 system).
+	 */
+	if (vscsi->client_data.partition_number == 0)
+		vscsi->client_data.partition_number =
+			be32_to_cpu(info->partition_number);
+	strncpy(vscsi->client_data.srp_version, info->srp_version,
+		sizeof(vscsi->client_data.srp_version));
+	strncpy(vscsi->client_data.partition_name, info->partition_name,
+		sizeof(vscsi->client_data.partition_name));
+	vscsi->client_data.mad_version = be32_to_cpu(info->mad_version);
+	vscsi->client_data.os_type = be32_to_cpu(info->os_type);
+
+	/* Copy our info */
+	strncpy(info->srp_version, SRP_VERSION,
+		sizeof(info->srp_version));
+	strncpy(info->partition_name, vscsi->dds.partition_name,
+		sizeof(info->partition_name));
+	info->partition_number = cpu_to_be32(vscsi->dds.partition_num);
+	info->mad_version = cpu_to_be32(MAD_VERSION_1);
+	info->os_type = cpu_to_be32(LINUX);
+	memset(&info->port_max_txu[0], 0, sizeof(info->port_max_txu));
+	info->port_max_txu[0] = cpu_to_be32(MAX_TXU);
+
+	dma_wmb();
+	rc = h_copy_rdma(sizeof(*info), vscsi->dds.window[LOCAL].liobn,
+			 token, vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(mad->buffer));
+	switch (rc) {
+	case H_SUCCESS:
+		break;
+
+	case H_SOURCE_PARM:
+	case H_DEST_PARM:
+	case H_PERMISSION:
+		if (connection_broken(vscsi))
+			flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
+		fallthrough;
+	default:
+		dev_err(&vscsi->dev, "adapter_info: h_copy_rdma to client failed, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi,
+					  ERR_DISCONNECT_RECONNECT,
+					  flag_bits);
+		break;
+	}
+
+free_dma:
+	dma_free_coherent(&vscsi->dma_dev->dev, sizeof(*info), info, token);
+	dev_dbg(&vscsi->dev, "Leaving adapter_info, rc %ld\n", rc);
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_cap_mad() - Service a Capabilities MAnagement Data gram
+ * @vscsi:	Pointer to our adapter structure
+ * @iue:	Information Unit containing the Capabilities MAD request
+ *
+ * NOTE: if you return an error from this routine you must be
+ * disconnecting or you will cause a hang
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt called with adapter lock held
+ */
+static int ibmvscsis_cap_mad(struct scsi_info *vscsi, struct iu_entry *iue)
+{
+	struct viosrp_capabilities *mad = &vio_iu(iue)->mad.capabilities;
+	struct capabilities *cap;
+	struct mad_capability_common *common;
+	dma_addr_t token;
+	u16 olen, len, status, min_len, cap_len;
+	u32 flag;
+	uint flag_bits = 0;
+	long rc = 0;
+
+	olen = be16_to_cpu(mad->common.length);
+	/*
+	 * struct capabilities hardcodes a couple capabilities after the
+	 * header, but the capabilities can actually be in any order.
+	 */
+	min_len = offsetof(struct capabilities, migration);
+	if ((olen < min_len) || (olen > PAGE_SIZE)) {
+		dev_warn(&vscsi->dev, "cap_mad: invalid len %d\n", olen);
+		mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
+		return 0;
+	}
+
+	cap = dma_alloc_coherent(&vscsi->dma_dev->dev, olen, &token,
+				 GFP_ATOMIC);
+	if (!cap) {
+		dev_err(&vscsi->dev, "bad dma_alloc_coherent %p\n",
+			iue->target);
+		mad->common.status = cpu_to_be16(VIOSRP_MAD_FAILED);
+		return 0;
+	}
+	rc = h_copy_rdma(olen, vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(mad->buffer),
+			 vscsi->dds.window[LOCAL].liobn, token);
+	if (rc == H_SUCCESS) {
+		strncpy(cap->name, dev_name(&vscsi->dma_dev->dev),
+			SRP_MAX_LOC_LEN);
+
+		len = olen - min_len;
+		status = VIOSRP_MAD_SUCCESS;
+		common = (struct mad_capability_common *)&cap->migration;
+
+		while ((len > 0) && (status == VIOSRP_MAD_SUCCESS) && !rc) {
+			dev_dbg(&vscsi->dev, "cap_mad: len left %hd, cap type %d, cap len %hd\n",
+				len, be32_to_cpu(common->cap_type),
+				be16_to_cpu(common->length));
+
+			cap_len = be16_to_cpu(common->length);
+			if (cap_len > len) {
+				dev_err(&vscsi->dev, "cap_mad: cap len mismatch with total len\n");
+				status = VIOSRP_MAD_FAILED;
+				break;
+			}
+
+			if (cap_len == 0) {
+				dev_err(&vscsi->dev, "cap_mad: cap len is 0\n");
+				status = VIOSRP_MAD_FAILED;
+				break;
+			}
+
+			switch (common->cap_type) {
+			default:
+				dev_dbg(&vscsi->dev, "cap_mad: unsupported capability\n");
+				common->server_support = 0;
+				flag = cpu_to_be32((u32)CAP_LIST_SUPPORTED);
+				cap->flags &= ~flag;
+				break;
+			}
+
+			len = len - cap_len;
+			common = (struct mad_capability_common *)
+				((char *)common + cap_len);
+		}
+
+		mad->common.status = cpu_to_be16(status);
+
+		dma_wmb();
+		rc = h_copy_rdma(olen, vscsi->dds.window[LOCAL].liobn, token,
+				 vscsi->dds.window[REMOTE].liobn,
+				 be64_to_cpu(mad->buffer));
+
+		if (rc != H_SUCCESS) {
+			dev_dbg(&vscsi->dev, "cap_mad: failed to copy to client, rc %ld\n",
+				rc);
+
+			if (rc == H_PERMISSION) {
+				if (connection_broken(vscsi))
+					flag_bits = (RESPONSE_Q_DOWN |
+						     CLIENT_FAILED);
+			}
+
+			dev_warn(&vscsi->dev, "cap_mad: error copying data to client, rc %ld\n",
+				 rc);
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT,
+						  flag_bits);
+		}
+	}
+
+	dma_free_coherent(&vscsi->dma_dev->dev, olen, cap, token);
+
+	dev_dbg(&vscsi->dev, "Leaving cap_mad, rc %ld, client_cap 0x%x\n",
+		rc, vscsi->client_cap);
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_process_mad() - Service a MAnagement Data gram
+ * @vscsi:	Pointer to our adapter structure
+ * @iue:	Information Unit containing the MAD request
+ *
+ * Must be called with interrupt lock held.
+ */
+static long ibmvscsis_process_mad(struct scsi_info *vscsi, struct iu_entry *iue)
+{
+	struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
+	struct viosrp_empty_iu *empty;
+	long rc = ADAPT_SUCCESS;
+
+	switch (be32_to_cpu(mad->type)) {
+	case VIOSRP_EMPTY_IU_TYPE:
+		empty = &vio_iu(iue)->mad.empty_iu;
+		vscsi->empty_iu_id = be64_to_cpu(empty->buffer);
+		vscsi->empty_iu_tag = be64_to_cpu(empty->common.tag);
+		mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
+		break;
+	case VIOSRP_ADAPTER_INFO_TYPE:
+		rc = ibmvscsis_adapter_info(vscsi, iue);
+		break;
+	case VIOSRP_CAPABILITIES_TYPE:
+		rc = ibmvscsis_cap_mad(vscsi, iue);
+		break;
+	case VIOSRP_ENABLE_FAST_FAIL:
+		if (vscsi->state == CONNECTED) {
+			vscsi->fast_fail = true;
+			mad->status = cpu_to_be16(VIOSRP_MAD_SUCCESS);
+		} else {
+			dev_warn(&vscsi->dev, "fast fail mad sent after login\n");
+			mad->status = cpu_to_be16(VIOSRP_MAD_FAILED);
+		}
+		break;
+	default:
+		mad->status = cpu_to_be16(VIOSRP_MAD_NOT_SUPPORTED);
+		break;
+	}
+
+	return rc;
+}
+
+/**
+ * srp_snd_msg_failed() - Handle an error when sending a response
+ * @vscsi:	Pointer to our adapter structure
+ * @rc:		The return code from the h_send_crq command
+ *
+ * Must be called with interrupt lock held.
+ */
+static void srp_snd_msg_failed(struct scsi_info *vscsi, long rc)
+{
+	ktime_t kt;
+
+	if (rc != H_DROPPED) {
+		ibmvscsis_free_cmd_qs(vscsi);
+
+		if (rc == H_CLOSED)
+			vscsi->flags |= CLIENT_FAILED;
+
+		/* don't flag the same problem multiple times */
+		if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
+			vscsi->flags |= RESPONSE_Q_DOWN;
+			if (!(vscsi->state & (ERR_DISCONNECT |
+					      ERR_DISCONNECT_RECONNECT |
+					      ERR_DISCONNECTED | UNDEFINED))) {
+				dev_err(&vscsi->dev, "snd_msg_failed: setting RESPONSE_Q_DOWN, state 0x%hx, flags 0x%x, rc %ld\n",
+					vscsi->state, vscsi->flags, rc);
+			}
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT, 0);
+		}
+		return;
+	}
+
+	/*
+	 * The response queue is full.
+	 * If the server is processing SRP requests, i.e.
+	 * the client has successfully done an
+	 * SRP_LOGIN, then it will wait forever for room in
+	 * the queue.  However if the system admin
+	 * is attempting to unconfigure the server then one
+	 * or more children will be in a state where
+	 * they are being removed. So if there is even one
+	 * child being removed then the driver assumes
+	 * the system admin is attempting to break the
+	 * connection with the client and MAX_TIMER_POPS
+	 * is honored.
+	 */
+	if ((vscsi->rsp_q_timer.timer_pops < MAX_TIMER_POPS) ||
+	    (vscsi->state == SRP_PROCESSING)) {
+		dev_dbg(&vscsi->dev, "snd_msg_failed: response queue full, flags 0x%x, timer started %d, pops %d\n",
+			vscsi->flags, (int)vscsi->rsp_q_timer.started,
+			vscsi->rsp_q_timer.timer_pops);
+
+		/*
+		 * Check if the timer is running; if it
+		 * is not then start it up.
+		 */
+		if (!vscsi->rsp_q_timer.started) {
+			if (vscsi->rsp_q_timer.timer_pops <
+			    MAX_TIMER_POPS) {
+				kt = WAIT_NANO_SECONDS;
+			} else {
+				/*
+				 * slide the timeslice if the maximum
+				 * timer pops have already happened
+				 */
+				kt = ktime_set(WAIT_SECONDS, 0);
+			}
+
+			vscsi->rsp_q_timer.started = true;
+			hrtimer_start(&vscsi->rsp_q_timer.timer, kt,
+				      HRTIMER_MODE_REL);
+		}
+	} else {
+		/*
+		 * TBD: Do we need to worry about this? Need to get
+		 *      remove working.
+		 */
+		/*
+		 * waited a long time and it appears the system admin
+		 * is bring this driver down
+		 */
+		vscsi->flags |= RESPONSE_Q_DOWN;
+		ibmvscsis_free_cmd_qs(vscsi);
+		/*
+		 * if the driver is already attempting to disconnect
+		 * from the client and has already logged an error
+		 * trace this event but don't put it in the error log
+		 */
+		if (!(vscsi->state & (ERR_DISCONNECT |
+				      ERR_DISCONNECT_RECONNECT |
+				      ERR_DISCONNECTED | UNDEFINED))) {
+			dev_err(&vscsi->dev, "client crq full too long\n");
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT,
+						  0);
+		}
+	}
+}
+
+/**
+ * ibmvscsis_send_messages() - Send a Response
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Send a response, first checking the waiting queue. Responses are
+ * sent in order they are received. If the response cannot be sent,
+ * because the client queue is full, it stays on the waiting queue.
+ *
+ * PRECONDITION:
+ *	Called with interrupt lock held
+ */
+static void ibmvscsis_send_messages(struct scsi_info *vscsi)
+{
+	struct viosrp_crq empty_crq = { };
+	struct viosrp_crq *crq = &empty_crq;
+	struct ibmvscsis_cmd *cmd, *nxt;
+	long rc = ADAPT_SUCCESS;
+	bool retry = false;
+
+	if (!(vscsi->flags & RESPONSE_Q_DOWN)) {
+		do {
+			retry = false;
+			list_for_each_entry_safe(cmd, nxt, &vscsi->waiting_rsp,
+						 list) {
+				/*
+				 * Check to make sure abort cmd gets processed
+				 * prior to the abort tmr cmd
+				 */
+				if (cmd->flags & DELAY_SEND)
+					continue;
+
+				if (cmd->abort_cmd) {
+					retry = true;
+					cmd->abort_cmd->flags &= ~(DELAY_SEND);
+					cmd->abort_cmd = NULL;
+				}
+
+				/*
+				 * If CMD_T_ABORTED w/o CMD_T_TAS scenarios and
+				 * the case where LIO issued a
+				 * ABORT_TASK: Sending TMR_TASK_DOES_NOT_EXIST
+				 * case then we dont send a response, since it
+				 * was already done.
+				 */
+				if (cmd->se_cmd.transport_state & CMD_T_ABORTED &&
+				    !(cmd->se_cmd.transport_state & CMD_T_TAS)) {
+					list_del(&cmd->list);
+					ibmvscsis_free_cmd_resources(vscsi,
+								     cmd);
+					/*
+					 * With a successfully aborted op
+					 * through LIO we want to increment the
+					 * the vscsi credit so that when we dont
+					 * send a rsp to the original scsi abort
+					 * op (h_send_crq), but the tm rsp to
+					 * the abort is sent, the credit is
+					 * correctly sent with the abort tm rsp.
+					 * We would need 1 for the abort tm rsp
+					 * and 1 credit for the aborted scsi op.
+					 * Thus we need to increment here.
+					 * Also we want to increment the credit
+					 * here because we want to make sure
+					 * cmd is actually released first
+					 * otherwise the client will think it
+					 * it can send a new cmd, and we could
+					 * find ourselves short of cmd elements.
+					 */
+					vscsi->credit += 1;
+				} else {
+					crq->valid = VALID_CMD_RESP_EL;
+					crq->format = cmd->rsp.format;
+
+					if (cmd->flags & CMD_FAST_FAIL)
+						crq->status = VIOSRP_ADAPTER_FAIL;
+
+					crq->IU_length = cpu_to_be16(cmd->rsp.len);
+
+					rc = h_send_crq(vscsi->dma_dev->unit_address,
+							be64_to_cpu(crq->high),
+							be64_to_cpu(cmd->rsp.tag));
+
+					dev_dbg(&vscsi->dev, "send_messages: cmd %p, tag 0x%llx, rc %ld\n",
+						cmd, be64_to_cpu(cmd->rsp.tag),
+						rc);
+
+					/* if all ok free up the command
+					 * element resources
+					 */
+					if (rc == H_SUCCESS) {
+						/* some movement has occurred */
+						vscsi->rsp_q_timer.timer_pops = 0;
+						list_del(&cmd->list);
+
+						ibmvscsis_free_cmd_resources(vscsi,
+									     cmd);
+					} else {
+						srp_snd_msg_failed(vscsi, rc);
+						break;
+					}
+				}
+			}
+		} while (retry);
+
+		if (!rc) {
+			/*
+			 * The timer could pop with the queue empty.  If
+			 * this happens, rc will always indicate a
+			 * success; clear the pop count.
+			 */
+			vscsi->rsp_q_timer.timer_pops = 0;
+		}
+	} else {
+		ibmvscsis_free_cmd_qs(vscsi);
+	}
+}
+
+/* Called with intr lock held */
+static void ibmvscsis_send_mad_resp(struct scsi_info *vscsi,
+				    struct ibmvscsis_cmd *cmd,
+				    struct viosrp_crq *crq)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct mad_common *mad = (struct mad_common *)&vio_iu(iue)->mad;
+	uint flag_bits = 0;
+	long rc;
+
+	dma_wmb();
+	rc = h_copy_rdma(sizeof(struct mad_common),
+			 vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
+			 vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(crq->IU_data_ptr));
+	if (!rc) {
+		cmd->rsp.format = VIOSRP_MAD_FORMAT;
+		cmd->rsp.len = sizeof(struct mad_common);
+		cmd->rsp.tag = mad->tag;
+		list_add_tail(&cmd->list, &vscsi->waiting_rsp);
+		ibmvscsis_send_messages(vscsi);
+	} else {
+		dev_dbg(&vscsi->dev, "Error sending mad response, rc %ld\n",
+			rc);
+		if (rc == H_PERMISSION) {
+			if (connection_broken(vscsi))
+				flag_bits = (RESPONSE_Q_DOWN | CLIENT_FAILED);
+		}
+		dev_err(&vscsi->dev, "mad: failed to copy to client, rc %ld\n",
+			rc);
+
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
+					  flag_bits);
+	}
+}
+
+/**
+ * ibmvscsis_mad() - Service a MAnagement Data gram.
+ * @vscsi:	Pointer to our adapter structure
+ * @crq:	Pointer to the CRQ entry containing the MAD request
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, called with adapter lock held
+ */
+static long ibmvscsis_mad(struct scsi_info *vscsi, struct viosrp_crq *crq)
+{
+	struct iu_entry *iue;
+	struct ibmvscsis_cmd *cmd;
+	struct mad_common *mad;
+	long rc = ADAPT_SUCCESS;
+
+	switch (vscsi->state) {
+		/*
+		 * We have not exchanged Init Msgs yet, so this MAD was sent
+		 * before the last Transport Event; client will not be
+		 * expecting a response.
+		 */
+	case WAIT_CONNECTION:
+		dev_dbg(&vscsi->dev, "mad: in Wait Connection state, ignoring MAD, flags %d\n",
+			vscsi->flags);
+		return ADAPT_SUCCESS;
+
+	case SRP_PROCESSING:
+	case CONNECTED:
+		break;
+
+		/*
+		 * We should never get here while we're in these states.
+		 * Just log an error and get out.
+		 */
+	case UNCONFIGURING:
+	case WAIT_IDLE:
+	case ERR_DISCONNECT:
+	case ERR_DISCONNECT_RECONNECT:
+	default:
+		dev_err(&vscsi->dev, "mad: invalid adapter state %d for mad\n",
+			vscsi->state);
+		return ADAPT_SUCCESS;
+	}
+
+	cmd = ibmvscsis_get_free_cmd(vscsi);
+	if (!cmd) {
+		dev_err(&vscsi->dev, "mad: failed to get cmd, debit %d\n",
+			vscsi->debit);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		return ERROR;
+	}
+	iue = cmd->iue;
+	cmd->type = ADAPTER_MAD;
+
+	rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
+	if (!rc) {
+		mad = (struct mad_common *)&vio_iu(iue)->mad;
+
+		dev_dbg(&vscsi->dev, "mad: type %d\n", be32_to_cpu(mad->type));
+
+		rc = ibmvscsis_process_mad(vscsi, iue);
+
+		dev_dbg(&vscsi->dev, "mad: status %hd, rc %ld\n",
+			be16_to_cpu(mad->status), rc);
+
+		if (!rc)
+			ibmvscsis_send_mad_resp(vscsi, cmd, crq);
+	} else {
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+	}
+
+	dev_dbg(&vscsi->dev, "Leaving mad, rc %ld\n", rc);
+	return rc;
+}
+
+/**
+ * ibmvscsis_login_rsp() - Create/copy a login response notice to the client
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Pointer to the command for the SRP Login request
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_login_rsp(struct scsi_info *vscsi,
+				struct ibmvscsis_cmd *cmd)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_login_rsp *rsp = &vio_iu(iue)->srp.login_rsp;
+	struct format_code *fmt;
+	uint flag_bits = 0;
+	long rc = ADAPT_SUCCESS;
+
+	memset(rsp, 0, sizeof(struct srp_login_rsp));
+
+	rsp->opcode = SRP_LOGIN_RSP;
+	rsp->req_lim_delta = cpu_to_be32(vscsi->request_limit);
+	rsp->tag = cmd->rsp.tag;
+	rsp->max_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
+	rsp->max_ti_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
+	fmt = (struct format_code *)&rsp->buf_fmt;
+	fmt->buffers = SUPPORTED_FORMATS;
+	vscsi->credit = 0;
+
+	cmd->rsp.len = sizeof(struct srp_login_rsp);
+
+	dma_wmb();
+	rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
+			 iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(iue->remote_token));
+
+	switch (rc) {
+	case H_SUCCESS:
+		break;
+
+	case H_PERMISSION:
+		if (connection_broken(vscsi))
+			flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
+		dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
+					  flag_bits);
+		break;
+	case H_SOURCE_PARM:
+	case H_DEST_PARM:
+	default:
+		dev_err(&vscsi->dev, "login_rsp: error copying to client, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_srp_login_rej() - Create/copy a login rejection notice to client
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Pointer to the command for the SRP Login request
+ * @reason:	The reason the SRP Login is being rejected, per SRP protocol
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_srp_login_rej(struct scsi_info *vscsi,
+				    struct ibmvscsis_cmd *cmd, u32 reason)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_login_rej *rej = &vio_iu(iue)->srp.login_rej;
+	struct format_code *fmt;
+	uint flag_bits = 0;
+	long rc = ADAPT_SUCCESS;
+
+	memset(rej, 0, sizeof(*rej));
+
+	rej->opcode = SRP_LOGIN_REJ;
+	rej->reason = cpu_to_be32(reason);
+	rej->tag = cmd->rsp.tag;
+	fmt = (struct format_code *)&rej->buf_fmt;
+	fmt->buffers = SUPPORTED_FORMATS;
+
+	cmd->rsp.len = sizeof(*rej);
+
+	dma_wmb();
+	rc = h_copy_rdma(cmd->rsp.len, vscsi->dds.window[LOCAL].liobn,
+			 iue->sbuf->dma, vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(iue->remote_token));
+
+	switch (rc) {
+	case H_SUCCESS:
+		break;
+	case H_PERMISSION:
+		if (connection_broken(vscsi))
+			flag_bits = RESPONSE_Q_DOWN | CLIENT_FAILED;
+		dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT,
+					  flag_bits);
+		break;
+	case H_SOURCE_PARM:
+	case H_DEST_PARM:
+	default:
+		dev_err(&vscsi->dev, "login_rej: error copying to client, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	}
+
+	return rc;
+}
+
+static int ibmvscsis_make_nexus(struct ibmvscsis_tport *tport)
+{
+	char *name = tport->tport_name;
+	struct ibmvscsis_nexus *nexus;
+	struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
+	int rc;
+
+	if (tport->ibmv_nexus) {
+		dev_dbg(&vscsi->dev, "tport->ibmv_nexus already exists\n");
+		return 0;
+	}
+
+	nexus = kzalloc(sizeof(*nexus), GFP_KERNEL);
+	if (!nexus) {
+		dev_err(&vscsi->dev, "Unable to allocate struct ibmvscsis_nexus\n");
+		return -ENOMEM;
+	}
+
+	nexus->se_sess = target_setup_session(&tport->se_tpg, 0, 0,
+					      TARGET_PROT_NORMAL, name, nexus,
+					      NULL);
+	if (IS_ERR(nexus->se_sess)) {
+		rc = PTR_ERR(nexus->se_sess);
+		goto transport_init_fail;
+	}
+
+	tport->ibmv_nexus = nexus;
+
+	return 0;
+
+transport_init_fail:
+	kfree(nexus);
+	return rc;
+}
+
+static int ibmvscsis_drop_nexus(struct ibmvscsis_tport *tport)
+{
+	struct se_session *se_sess;
+	struct ibmvscsis_nexus *nexus;
+
+	nexus = tport->ibmv_nexus;
+	if (!nexus)
+		return -ENODEV;
+
+	se_sess = nexus->se_sess;
+	if (!se_sess)
+		return -ENODEV;
+
+	/*
+	 * Release the SCSI I_T Nexus to the emulated ibmvscsis Target Port
+	 */
+	target_remove_session(se_sess);
+	tport->ibmv_nexus = NULL;
+	kfree(nexus);
+
+	return 0;
+}
+
+/**
+ * ibmvscsis_srp_login() - Process an SRP Login Request
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Command element to use to process the SRP Login request
+ * @crq:	Pointer to CRQ entry containing the SRP Login request
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, called with interrupt lock held
+ */
+static long ibmvscsis_srp_login(struct scsi_info *vscsi,
+				struct ibmvscsis_cmd *cmd,
+				struct viosrp_crq *crq)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_login_req *req = &vio_iu(iue)->srp.login_req;
+	struct port_id {
+		__be64 id_extension;
+		__be64 io_guid;
+	} *iport, *tport;
+	struct format_code *fmt;
+	u32 reason = 0x0;
+	long rc = ADAPT_SUCCESS;
+
+	iport = (struct port_id *)req->initiator_port_id;
+	tport = (struct port_id *)req->target_port_id;
+	fmt = (struct format_code *)&req->req_buf_fmt;
+	if (be32_to_cpu(req->req_it_iu_len) > SRP_MAX_IU_LEN)
+		reason = SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE;
+	else if (be32_to_cpu(req->req_it_iu_len) < 64)
+		reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
+	else if ((be64_to_cpu(iport->id_extension) > (MAX_NUM_PORTS - 1)) ||
+		 (be64_to_cpu(tport->id_extension) > (MAX_NUM_PORTS - 1)))
+		reason = SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL;
+	else if (req->req_flags & SRP_MULTICHAN_MULTI)
+		reason = SRP_LOGIN_REJ_MULTI_CHANNEL_UNSUPPORTED;
+	else if (fmt->buffers & (~SUPPORTED_FORMATS))
+		reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
+	else if ((fmt->buffers & SUPPORTED_FORMATS) == 0)
+		reason = SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT;
+
+	if (vscsi->state == SRP_PROCESSING)
+		reason = SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED;
+
+	rc = ibmvscsis_make_nexus(&vscsi->tport);
+	if (rc)
+		reason = SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL;
+
+	cmd->rsp.format = VIOSRP_SRP_FORMAT;
+	cmd->rsp.tag = req->tag;
+
+	dev_dbg(&vscsi->dev, "srp_login: reason 0x%x\n", reason);
+
+	if (reason)
+		rc = ibmvscsis_srp_login_rej(vscsi, cmd, reason);
+	else
+		rc = ibmvscsis_login_rsp(vscsi, cmd);
+
+	if (!rc) {
+		if (!reason)
+			vscsi->state = SRP_PROCESSING;
+
+		list_add_tail(&cmd->list, &vscsi->waiting_rsp);
+		ibmvscsis_send_messages(vscsi);
+	} else {
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+	}
+
+	dev_dbg(&vscsi->dev, "Leaving srp_login, rc %ld\n", rc);
+	return rc;
+}
+
+/**
+ * ibmvscsis_srp_i_logout() - Helper Function to close I_T Nexus
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Command element to use to process the Implicit Logout request
+ * @crq:	Pointer to CRQ entry containing the Implicit Logout request
+ *
+ * Do the logic to close the I_T nexus.  This function may not
+ * behave to specification.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_srp_i_logout(struct scsi_info *vscsi,
+				   struct ibmvscsis_cmd *cmd,
+				   struct viosrp_crq *crq)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_i_logout *log_out = &vio_iu(iue)->srp.i_logout;
+
+	if ((vscsi->debit > 0) || !list_empty(&vscsi->schedule_q) ||
+	    !list_empty(&vscsi->waiting_rsp)) {
+		dev_err(&vscsi->dev, "i_logout: outstanding work\n");
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
+	} else {
+		cmd->rsp.format = SRP_FORMAT;
+		cmd->rsp.tag = log_out->tag;
+		cmd->rsp.len = sizeof(struct mad_common);
+		list_add_tail(&cmd->list, &vscsi->waiting_rsp);
+		ibmvscsis_send_messages(vscsi);
+
+		ibmvscsis_post_disconnect(vscsi, WAIT_IDLE, 0);
+	}
+
+	return ADAPT_SUCCESS;
+}
+
+/* Called with intr lock held */
+static void ibmvscsis_srp_cmd(struct scsi_info *vscsi, struct viosrp_crq *crq)
+{
+	struct ibmvscsis_cmd *cmd;
+	struct iu_entry *iue;
+	struct srp_cmd *srp;
+	struct srp_tsk_mgmt *tsk;
+	long rc;
+
+	if (vscsi->request_limit - vscsi->debit <= 0) {
+		/* Client has exceeded request limit */
+		dev_err(&vscsi->dev, "Client exceeded the request limit (%d), debit %d\n",
+			vscsi->request_limit, vscsi->debit);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		return;
+	}
+
+	cmd = ibmvscsis_get_free_cmd(vscsi);
+	if (!cmd) {
+		dev_err(&vscsi->dev, "srp_cmd failed to get cmd, debit %d\n",
+			vscsi->debit);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		return;
+	}
+	iue = cmd->iue;
+	srp = &vio_iu(iue)->srp.cmd;
+
+	rc = ibmvscsis_copy_crq_packet(vscsi, cmd, crq);
+	if (rc) {
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+		return;
+	}
+
+	if (vscsi->state == SRP_PROCESSING) {
+		switch (srp->opcode) {
+		case SRP_LOGIN_REQ:
+			rc = ibmvscsis_srp_login(vscsi, cmd, crq);
+			break;
+
+		case SRP_TSK_MGMT:
+			tsk = &vio_iu(iue)->srp.tsk_mgmt;
+			dev_dbg(&vscsi->dev, "tsk_mgmt tag: %llu (0x%llx)\n",
+				tsk->tag, tsk->tag);
+			cmd->rsp.tag = tsk->tag;
+			vscsi->debit += 1;
+			cmd->type = TASK_MANAGEMENT;
+			list_add_tail(&cmd->list, &vscsi->schedule_q);
+			queue_work(vscsi->work_q, &cmd->work);
+			break;
+
+		case SRP_CMD:
+			dev_dbg(&vscsi->dev, "srp_cmd tag: %llu (0x%llx)\n",
+				srp->tag, srp->tag);
+			cmd->rsp.tag = srp->tag;
+			vscsi->debit += 1;
+			cmd->type = SCSI_CDB;
+			/*
+			 * We want to keep track of work waiting for
+			 * the workqueue.
+			 */
+			list_add_tail(&cmd->list, &vscsi->schedule_q);
+			queue_work(vscsi->work_q, &cmd->work);
+			break;
+
+		case SRP_I_LOGOUT:
+			rc = ibmvscsis_srp_i_logout(vscsi, cmd, crq);
+			break;
+
+		case SRP_CRED_RSP:
+		case SRP_AER_RSP:
+		default:
+			ibmvscsis_free_cmd_resources(vscsi, cmd);
+			dev_err(&vscsi->dev, "invalid srp cmd, opcode %d\n",
+				(uint)srp->opcode);
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT, 0);
+			break;
+		}
+	} else if (srp->opcode == SRP_LOGIN_REQ && vscsi->state == CONNECTED) {
+		rc = ibmvscsis_srp_login(vscsi, cmd, crq);
+	} else {
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+		dev_err(&vscsi->dev, "Invalid state %d to handle srp cmd\n",
+			vscsi->state);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+	}
+}
+
+/**
+ * ibmvscsis_ping_response() - Respond to a ping request
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Let the client know that the server is alive and waiting on
+ * its native I/O stack.
+ * If any type of error occurs from the call to queue a ping
+ * response then the client is either not accepting or receiving
+ * interrupts.  Disconnect with an error.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, interrupt lock held
+ */
+static long ibmvscsis_ping_response(struct scsi_info *vscsi)
+{
+	struct viosrp_crq *crq;
+	u64 buffer[2] = { 0, 0 };
+	long rc;
+
+	crq = (struct viosrp_crq *)&buffer;
+	crq->valid = VALID_CMD_RESP_EL;
+	crq->format = (u8)MESSAGE_IN_CRQ;
+	crq->status = PING_RESPONSE;
+
+	rc = h_send_crq(vscsi->dds.unit_id, cpu_to_be64(buffer[MSG_HI]),
+			cpu_to_be64(buffer[MSG_LOW]));
+
+	switch (rc) {
+	case H_SUCCESS:
+		break;
+	case H_CLOSED:
+		vscsi->flags |= CLIENT_FAILED;
+		fallthrough;
+	case H_DROPPED:
+		vscsi->flags |= RESPONSE_Q_DOWN;
+		fallthrough;
+	case H_REMOTE_PARM:
+		dev_err(&vscsi->dev, "ping_response: h_send_crq failed, rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	default:
+		dev_err(&vscsi->dev, "ping_response: h_send_crq returned unknown rc %ld\n",
+			rc);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
+		break;
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_parse_command() - Parse an element taken from the cmd rsp queue.
+ * @vscsi:	Pointer to our adapter structure
+ * @crq:	Pointer to CRQ element containing the SRP request
+ *
+ * This function will return success if the command queue element is valid
+ * and the srp iu or MAD request it pointed to was also valid.  That does
+ * not mean that an error was not returned to the client.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Interrupt, intr lock held
+ */
+static long ibmvscsis_parse_command(struct scsi_info *vscsi,
+				    struct viosrp_crq *crq)
+{
+	long rc = ADAPT_SUCCESS;
+
+	switch (crq->valid) {
+	case VALID_CMD_RESP_EL:
+		switch (crq->format) {
+		case OS400_FORMAT:
+		case AIX_FORMAT:
+		case LINUX_FORMAT:
+		case MAD_FORMAT:
+			if (vscsi->flags & PROCESSING_MAD) {
+				rc = ERROR;
+				dev_err(&vscsi->dev, "parse_command: already processing mad\n");
+				ibmvscsis_post_disconnect(vscsi,
+						       ERR_DISCONNECT_RECONNECT,
+						       0);
+			} else {
+				vscsi->flags |= PROCESSING_MAD;
+				rc = ibmvscsis_mad(vscsi, crq);
+			}
+			break;
+
+		case SRP_FORMAT:
+			ibmvscsis_srp_cmd(vscsi, crq);
+			break;
+
+		case MESSAGE_IN_CRQ:
+			if (crq->status == PING)
+				ibmvscsis_ping_response(vscsi);
+			break;
+
+		default:
+			dev_err(&vscsi->dev, "parse_command: invalid format %d\n",
+				(uint)crq->format);
+			ibmvscsis_post_disconnect(vscsi,
+						  ERR_DISCONNECT_RECONNECT, 0);
+			break;
+		}
+		break;
+
+	case VALID_TRANS_EVENT:
+		rc = ibmvscsis_trans_event(vscsi, crq);
+		break;
+
+	case VALID_INIT_MSG:
+		rc = ibmvscsis_init_msg(vscsi, crq);
+		break;
+
+	default:
+		dev_err(&vscsi->dev, "parse_command: invalid valid field %d\n",
+			(uint)crq->valid);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		break;
+	}
+
+	/*
+	 * Return only what the interrupt handler cares
+	 * about. Most errors we keep right on trucking.
+	 */
+	rc = vscsi->flags & SCHEDULE_DISCONNECT;
+
+	return rc;
+}
+
+static int read_dma_window(struct scsi_info *vscsi)
+{
+	struct vio_dev *vdev = vscsi->dma_dev;
+	const __be32 *dma_window;
+	const __be32 *prop;
+
+	/* TODO Using of_parse_dma_window would be better, but it doesn't give
+	 * a way to read multiple windows without already knowing the size of
+	 * a window or the number of windows.
+	 */
+	dma_window = (const __be32 *)vio_get_attribute(vdev,
+						       "ibm,my-dma-window",
+						       NULL);
+	if (!dma_window) {
+		dev_err(&vscsi->dev, "Couldn't find ibm,my-dma-window property\n");
+		return -1;
+	}
+
+	vscsi->dds.window[LOCAL].liobn = be32_to_cpu(*dma_window);
+	dma_window++;
+
+	prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-address-cells",
+						 NULL);
+	if (!prop) {
+		dev_warn(&vscsi->dev, "Couldn't find ibm,#dma-address-cells property\n");
+		dma_window++;
+	} else {
+		dma_window += be32_to_cpu(*prop);
+	}
+
+	prop = (const __be32 *)vio_get_attribute(vdev, "ibm,#dma-size-cells",
+						 NULL);
+	if (!prop) {
+		dev_warn(&vscsi->dev, "Couldn't find ibm,#dma-size-cells property\n");
+		dma_window++;
+	} else {
+		dma_window += be32_to_cpu(*prop);
+	}
+
+	/* dma_window should point to the second window now */
+	vscsi->dds.window[REMOTE].liobn = be32_to_cpu(*dma_window);
+
+	return 0;
+}
+
+static struct ibmvscsis_tport *ibmvscsis_lookup_port(const char *name)
+{
+	struct ibmvscsis_tport *tport = NULL;
+	struct vio_dev *vdev;
+	struct scsi_info *vscsi;
+
+	spin_lock_bh(&ibmvscsis_dev_lock);
+	list_for_each_entry(vscsi, &ibmvscsis_dev_list, list) {
+		vdev = vscsi->dma_dev;
+		if (!strcmp(dev_name(&vdev->dev), name)) {
+			tport = &vscsi->tport;
+			break;
+		}
+	}
+	spin_unlock_bh(&ibmvscsis_dev_lock);
+
+	return tport;
+}
+
+/**
+ * ibmvscsis_parse_cmd() - Parse SRP Command
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Pointer to command element with SRP command
+ *
+ * Parse the srp command; if it is valid then submit it to tcm.
+ * Note: The return code does not reflect the status of the SCSI CDB.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process level
+ */
+static void ibmvscsis_parse_cmd(struct scsi_info *vscsi,
+				struct ibmvscsis_cmd *cmd)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
+	struct ibmvscsis_nexus *nexus;
+	u64 data_len = 0;
+	enum dma_data_direction dir;
+	int attr = 0;
+
+	nexus = vscsi->tport.ibmv_nexus;
+	/*
+	 * additional length in bytes.  Note that the SRP spec says that
+	 * additional length is in 4-byte words, but technically the
+	 * additional length field is only the upper 6 bits of the byte.
+	 * The lower 2 bits are reserved.  If the lower 2 bits are 0 (as
+	 * all reserved fields should be), then interpreting the byte as
+	 * an int will yield the length in bytes.
+	 */
+	if (srp->add_cdb_len & 0x03) {
+		dev_err(&vscsi->dev, "parse_cmd: reserved bits set in IU\n");
+		spin_lock_bh(&vscsi->intr_lock);
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+		spin_unlock_bh(&vscsi->intr_lock);
+		return;
+	}
+
+	if (srp_get_desc_table(srp, &dir, &data_len)) {
+		dev_err(&vscsi->dev, "0x%llx: parsing SRP descriptor table failed.\n",
+			srp->tag);
+		goto fail;
+	}
+
+	cmd->rsp.sol_not = srp->sol_not;
+
+	switch (srp->task_attr) {
+	case SRP_SIMPLE_TASK:
+		attr = TCM_SIMPLE_TAG;
+		break;
+	case SRP_ORDERED_TASK:
+		attr = TCM_ORDERED_TAG;
+		break;
+	case SRP_HEAD_TASK:
+		attr = TCM_HEAD_TAG;
+		break;
+	case SRP_ACA_TASK:
+		attr = TCM_ACA_TAG;
+		break;
+	default:
+		dev_err(&vscsi->dev, "Invalid task attribute %d\n",
+			srp->task_attr);
+		goto fail;
+	}
+
+	cmd->se_cmd.tag = be64_to_cpu(srp->tag);
+
+	spin_lock_bh(&vscsi->intr_lock);
+	list_add_tail(&cmd->list, &vscsi->active_q);
+	spin_unlock_bh(&vscsi->intr_lock);
+
+	srp->lun.scsi_lun[0] &= 0x3f;
+
+	target_submit_cmd(&cmd->se_cmd, nexus->se_sess, srp->cdb,
+			  cmd->sense_buf, scsilun_to_int(&srp->lun),
+			  data_len, attr, dir, 0);
+	return;
+
+fail:
+	spin_lock_bh(&vscsi->intr_lock);
+	ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);
+	spin_unlock_bh(&vscsi->intr_lock);
+}
+
+/**
+ * ibmvscsis_parse_task() - Parse SRP Task Management Request
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Pointer to command element with SRP task management request
+ *
+ * Parse the srp task management request; if it is valid then submit it to tcm.
+ * Note: The return code does not reflect the status of the task management
+ * request.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Processor level
+ */
+static void ibmvscsis_parse_task(struct scsi_info *vscsi,
+				 struct ibmvscsis_cmd *cmd)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
+	int tcm_type;
+	u64 tag_to_abort = 0;
+	int rc = 0;
+	struct ibmvscsis_nexus *nexus;
+
+	nexus = vscsi->tport.ibmv_nexus;
+
+	cmd->rsp.sol_not = srp_tsk->sol_not;
+
+	switch (srp_tsk->tsk_mgmt_func) {
+	case SRP_TSK_ABORT_TASK:
+		tcm_type = TMR_ABORT_TASK;
+		tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
+		break;
+	case SRP_TSK_ABORT_TASK_SET:
+		tcm_type = TMR_ABORT_TASK_SET;
+		break;
+	case SRP_TSK_CLEAR_TASK_SET:
+		tcm_type = TMR_CLEAR_TASK_SET;
+		break;
+	case SRP_TSK_LUN_RESET:
+		tcm_type = TMR_LUN_RESET;
+		break;
+	case SRP_TSK_CLEAR_ACA:
+		tcm_type = TMR_CLEAR_ACA;
+		break;
+	default:
+		dev_err(&vscsi->dev, "unknown task mgmt func %d\n",
+			srp_tsk->tsk_mgmt_func);
+		cmd->se_cmd.se_tmr_req->response =
+			TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
+		rc = -1;
+		break;
+	}
+
+	if (!rc) {
+		cmd->se_cmd.tag = be64_to_cpu(srp_tsk->tag);
+
+		spin_lock_bh(&vscsi->intr_lock);
+		list_add_tail(&cmd->list, &vscsi->active_q);
+		spin_unlock_bh(&vscsi->intr_lock);
+
+		srp_tsk->lun.scsi_lun[0] &= 0x3f;
+
+		dev_dbg(&vscsi->dev, "calling submit_tmr, func %d\n",
+			srp_tsk->tsk_mgmt_func);
+		rc = target_submit_tmr(&cmd->se_cmd, nexus->se_sess, NULL,
+				       scsilun_to_int(&srp_tsk->lun), srp_tsk,
+				       tcm_type, GFP_KERNEL, tag_to_abort, 0);
+		if (rc) {
+			dev_err(&vscsi->dev, "target_submit_tmr failed, rc %d\n",
+				rc);
+			spin_lock_bh(&vscsi->intr_lock);
+			list_del(&cmd->list);
+			spin_unlock_bh(&vscsi->intr_lock);
+			cmd->se_cmd.se_tmr_req->response =
+				TMR_FUNCTION_REJECTED;
+		}
+	}
+
+	if (rc)
+		transport_send_check_condition_and_sense(&cmd->se_cmd, 0, 0);
+}
+
+static void ibmvscsis_scheduler(struct work_struct *work)
+{
+	struct ibmvscsis_cmd *cmd = container_of(work, struct ibmvscsis_cmd,
+						 work);
+	struct scsi_info *vscsi = cmd->adapter;
+
+	spin_lock_bh(&vscsi->intr_lock);
+
+	/* Remove from schedule_q */
+	list_del(&cmd->list);
+
+	/* Don't submit cmd if we're disconnecting */
+	if (vscsi->flags & (SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED)) {
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+
+		/* ibmvscsis_disconnect might be waiting for us */
+		if (list_empty(&vscsi->active_q) &&
+		    list_empty(&vscsi->schedule_q) &&
+		    (vscsi->flags & WAIT_FOR_IDLE)) {
+			vscsi->flags &= ~WAIT_FOR_IDLE;
+			complete(&vscsi->wait_idle);
+		}
+
+		spin_unlock_bh(&vscsi->intr_lock);
+		return;
+	}
+
+	spin_unlock_bh(&vscsi->intr_lock);
+
+	switch (cmd->type) {
+	case SCSI_CDB:
+		ibmvscsis_parse_cmd(vscsi, cmd);
+		break;
+	case TASK_MANAGEMENT:
+		ibmvscsis_parse_task(vscsi, cmd);
+		break;
+	default:
+		dev_err(&vscsi->dev, "scheduler, invalid cmd type %d\n",
+			cmd->type);
+		spin_lock_bh(&vscsi->intr_lock);
+		ibmvscsis_free_cmd_resources(vscsi, cmd);
+		spin_unlock_bh(&vscsi->intr_lock);
+		break;
+	}
+}
+
+static int ibmvscsis_alloc_cmds(struct scsi_info *vscsi, int num)
+{
+	struct ibmvscsis_cmd *cmd;
+	int i;
+
+	INIT_LIST_HEAD(&vscsi->free_cmd);
+	vscsi->cmd_pool = kcalloc(num, sizeof(struct ibmvscsis_cmd),
+				  GFP_KERNEL);
+	if (!vscsi->cmd_pool)
+		return -ENOMEM;
+
+	for (i = 0, cmd = (struct ibmvscsis_cmd *)vscsi->cmd_pool; i < num;
+	     i++, cmd++) {
+		cmd->abort_cmd = NULL;
+		cmd->adapter = vscsi;
+		INIT_WORK(&cmd->work, ibmvscsis_scheduler);
+		list_add_tail(&cmd->list, &vscsi->free_cmd);
+	}
+
+	return 0;
+}
+
+static void ibmvscsis_free_cmds(struct scsi_info *vscsi)
+{
+	kfree(vscsi->cmd_pool);
+	vscsi->cmd_pool = NULL;
+	INIT_LIST_HEAD(&vscsi->free_cmd);
+}
+
+/**
+ * ibmvscsis_service_wait_q() - Service Waiting Queue
+ * @timer:	Pointer to timer which has expired
+ *
+ * This routine is called when the timer pops to service the waiting
+ * queue. Elements on the queue have completed, their responses have been
+ * copied to the client, but the client's response queue was full so
+ * the queue message could not be sent. The routine grabs the proper locks
+ * and calls send messages.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	called at interrupt level
+ */
+static enum hrtimer_restart ibmvscsis_service_wait_q(struct hrtimer *timer)
+{
+	struct timer_cb *p_timer = container_of(timer, struct timer_cb, timer);
+	struct scsi_info *vscsi = container_of(p_timer, struct scsi_info,
+					       rsp_q_timer);
+
+	spin_lock_bh(&vscsi->intr_lock);
+	p_timer->timer_pops += 1;
+	p_timer->started = false;
+	ibmvscsis_send_messages(vscsi);
+	spin_unlock_bh(&vscsi->intr_lock);
+
+	return HRTIMER_NORESTART;
+}
+
+static long ibmvscsis_alloctimer(struct scsi_info *vscsi)
+{
+	struct timer_cb *p_timer;
+
+	p_timer = &vscsi->rsp_q_timer;
+	hrtimer_init(&p_timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+
+	p_timer->timer.function = ibmvscsis_service_wait_q;
+	p_timer->started = false;
+	p_timer->timer_pops = 0;
+
+	return ADAPT_SUCCESS;
+}
+
+static void ibmvscsis_freetimer(struct scsi_info *vscsi)
+{
+	struct timer_cb *p_timer;
+
+	p_timer = &vscsi->rsp_q_timer;
+
+	(void)hrtimer_cancel(&p_timer->timer);
+
+	p_timer->started = false;
+	p_timer->timer_pops = 0;
+}
+
+static irqreturn_t ibmvscsis_interrupt(int dummy, void *data)
+{
+	struct scsi_info *vscsi = data;
+
+	vio_disable_interrupts(vscsi->dma_dev);
+	tasklet_schedule(&vscsi->work_task);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ibmvscsis_enable_change_state() - Set new state based on enabled status
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * This function determines our new state now that we are enabled.  This
+ * may involve sending an Init Complete message to the client.
+ *
+ * Must be called with interrupt lock held.
+ */
+static long ibmvscsis_enable_change_state(struct scsi_info *vscsi)
+{
+	int bytes;
+	long rc = ADAPT_SUCCESS;
+
+	bytes = vscsi->cmd_q.size * PAGE_SIZE;
+	rc = h_reg_crq(vscsi->dds.unit_id, vscsi->cmd_q.crq_token, bytes);
+	if (rc == H_CLOSED || rc == H_SUCCESS) {
+		vscsi->state = WAIT_CONNECTION;
+		rc = ibmvscsis_establish_new_q(vscsi);
+	}
+
+	if (rc != ADAPT_SUCCESS) {
+		vscsi->state = ERR_DISCONNECTED;
+		vscsi->flags |= RESPONSE_Q_DOWN;
+	}
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_create_command_q() - Create Command Queue
+ * @vscsi:	Pointer to our adapter structure
+ * @num_cmds:	Currently unused.  In the future, may be used to determine
+ *		the size of the CRQ.
+ *
+ * Allocates memory for command queue maps remote memory into an ioba
+ * initializes the command response queue
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process level only
+ */
+static long ibmvscsis_create_command_q(struct scsi_info *vscsi, int num_cmds)
+{
+	int pages;
+	struct vio_dev *vdev = vscsi->dma_dev;
+
+	/* We might support multiple pages in the future, but just 1 for now */
+	pages = 1;
+
+	vscsi->cmd_q.size = pages;
+
+	vscsi->cmd_q.base_addr =
+		(struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
+	if (!vscsi->cmd_q.base_addr)
+		return -ENOMEM;
+
+	vscsi->cmd_q.mask = ((uint)pages * CRQ_PER_PAGE) - 1;
+
+	vscsi->cmd_q.crq_token = dma_map_single(&vdev->dev,
+						vscsi->cmd_q.base_addr,
+						PAGE_SIZE, DMA_BIDIRECTIONAL);
+	if (dma_mapping_error(&vdev->dev, vscsi->cmd_q.crq_token)) {
+		free_page((unsigned long)vscsi->cmd_q.base_addr);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * ibmvscsis_destroy_command_q - Destroy Command Queue
+ * @vscsi:	Pointer to our adapter structure
+ *
+ * Releases memory for command queue and unmaps mapped remote memory.
+ *
+ * EXECUTION ENVIRONMENT:
+ *	Process level only
+ */
+static void ibmvscsis_destroy_command_q(struct scsi_info *vscsi)
+{
+	dma_unmap_single(&vscsi->dma_dev->dev, vscsi->cmd_q.crq_token,
+			 PAGE_SIZE, DMA_BIDIRECTIONAL);
+	free_page((unsigned long)vscsi->cmd_q.base_addr);
+	vscsi->cmd_q.base_addr = NULL;
+	vscsi->state = NO_QUEUE;
+}
+
+static u8 ibmvscsis_fast_fail(struct scsi_info *vscsi,
+			      struct ibmvscsis_cmd *cmd)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct se_cmd *se_cmd = &cmd->se_cmd;
+	struct srp_cmd *srp = (struct srp_cmd *)iue->sbuf->buf;
+	struct scsi_sense_hdr sshdr;
+	u8 rc = se_cmd->scsi_status;
+
+	if (vscsi->fast_fail && (READ_CMD(srp->cdb) || WRITE_CMD(srp->cdb)))
+		if (scsi_normalize_sense(se_cmd->sense_buffer,
+					 se_cmd->scsi_sense_length, &sshdr))
+			if (sshdr.sense_key == HARDWARE_ERROR &&
+			    (se_cmd->residual_count == 0 ||
+			     se_cmd->residual_count == se_cmd->data_length)) {
+				rc = NO_SENSE;
+				cmd->flags |= CMD_FAST_FAIL;
+			}
+
+	return rc;
+}
+
+/**
+ * srp_build_response() - Build an SRP response buffer
+ * @vscsi:	Pointer to our adapter structure
+ * @cmd:	Pointer to command for which to send the response
+ * @len_p:	Where to return the length of the IU response sent.  This
+ *		is needed to construct the CRQ response.
+ *
+ * Build the SRP response buffer and copy it to the client's memory space.
+ */
+static long srp_build_response(struct scsi_info *vscsi,
+			       struct ibmvscsis_cmd *cmd, uint *len_p)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct se_cmd *se_cmd = &cmd->se_cmd;
+	struct srp_rsp *rsp;
+	uint len;
+	u32 rsp_code;
+	char *data;
+	u32 *tsk_status;
+	long rc = ADAPT_SUCCESS;
+
+	spin_lock_bh(&vscsi->intr_lock);
+
+	rsp = &vio_iu(iue)->srp.rsp;
+	len = sizeof(*rsp);
+	memset(rsp, 0, len);
+	data = rsp->data;
+
+	rsp->opcode = SRP_RSP;
+
+	rsp->req_lim_delta = cpu_to_be32(1 + vscsi->credit);
+	rsp->tag = cmd->rsp.tag;
+	rsp->flags = 0;
+
+	if (cmd->type == SCSI_CDB) {
+		rsp->status = ibmvscsis_fast_fail(vscsi, cmd);
+		if (rsp->status) {
+			dev_dbg(&vscsi->dev, "build_resp: cmd %p, scsi status %d\n",
+				cmd, (int)rsp->status);
+			ibmvscsis_determine_resid(se_cmd, rsp);
+			if (se_cmd->scsi_sense_length && se_cmd->sense_buffer) {
+				rsp->sense_data_len =
+					cpu_to_be32(se_cmd->scsi_sense_length);
+				rsp->flags |= SRP_RSP_FLAG_SNSVALID;
+				len += se_cmd->scsi_sense_length;
+				memcpy(data, se_cmd->sense_buffer,
+				       se_cmd->scsi_sense_length);
+			}
+			rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
+				UCSOLNT_RESP_SHIFT;
+		} else if (cmd->flags & CMD_FAST_FAIL) {
+			dev_dbg(&vscsi->dev, "build_resp: cmd %p, fast fail\n",
+				cmd);
+			rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
+				UCSOLNT_RESP_SHIFT;
+		} else {
+			rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
+				SCSOLNT_RESP_SHIFT;
+		}
+	} else {
+		/* this is task management */
+		rsp->status = 0;
+		rsp->resp_data_len = cpu_to_be32(4);
+		rsp->flags |= SRP_RSP_FLAG_RSPVALID;
+
+		switch (se_cmd->se_tmr_req->response) {
+		case TMR_FUNCTION_COMPLETE:
+		case TMR_TASK_DOES_NOT_EXIST:
+			rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_COMPLETE;
+			rsp->sol_not = (cmd->rsp.sol_not & SCSOLNT) >>
+				SCSOLNT_RESP_SHIFT;
+			break;
+		case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
+		case TMR_LUN_DOES_NOT_EXIST:
+			rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_NOT_SUPPORTED;
+			rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
+				UCSOLNT_RESP_SHIFT;
+			break;
+		case TMR_FUNCTION_FAILED:
+		case TMR_FUNCTION_REJECTED:
+		default:
+			rsp_code = SRP_TASK_MANAGEMENT_FUNCTION_FAILED;
+			rsp->sol_not = (cmd->rsp.sol_not & UCSOLNT) >>
+				UCSOLNT_RESP_SHIFT;
+			break;
+		}
+
+		tsk_status = (u32 *)data;
+		*tsk_status = cpu_to_be32(rsp_code);
+		data = (char *)(tsk_status + 1);
+		len += 4;
+	}
+
+	dma_wmb();
+	rc = h_copy_rdma(len, vscsi->dds.window[LOCAL].liobn, iue->sbuf->dma,
+			 vscsi->dds.window[REMOTE].liobn,
+			 be64_to_cpu(iue->remote_token));
+
+	switch (rc) {
+	case H_SUCCESS:
+		vscsi->credit = 0;
+		*len_p = len;
+		break;
+	case H_PERMISSION:
+		if (connection_broken(vscsi))
+			vscsi->flags |= RESPONSE_Q_DOWN | CLIENT_FAILED;
+
+		dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld, flags 0x%x, state 0x%hx\n",
+			rc, vscsi->flags, vscsi->state);
+		break;
+	case H_SOURCE_PARM:
+	case H_DEST_PARM:
+	default:
+		dev_err(&vscsi->dev, "build_response: error copying to client, rc %ld\n",
+			rc);
+		break;
+	}
+
+	spin_unlock_bh(&vscsi->intr_lock);
+
+	return rc;
+}
+
+static int ibmvscsis_rdma(struct ibmvscsis_cmd *cmd, struct scatterlist *sg,
+			  int nsg, struct srp_direct_buf *md, int nmd,
+			  enum dma_data_direction dir, unsigned int bytes)
+{
+	struct iu_entry *iue = cmd->iue;
+	struct srp_target *target = iue->target;
+	struct scsi_info *vscsi = target->ldata;
+	struct scatterlist *sgp;
+	dma_addr_t client_ioba, server_ioba;
+	ulong buf_len;
+	ulong client_len, server_len;
+	int md_idx;
+	long tx_len;
+	long rc = 0;
+
+	if (bytes == 0)
+		return 0;
+
+	sgp = sg;
+	client_len = 0;
+	server_len = 0;
+	md_idx = 0;
+	tx_len = bytes;
+
+	do {
+		if (client_len == 0) {
+			if (md_idx >= nmd) {
+				dev_err(&vscsi->dev, "rdma: ran out of client memory descriptors\n");
+				rc = -EIO;
+				break;
+			}
+			client_ioba = be64_to_cpu(md[md_idx].va);
+			client_len = be32_to_cpu(md[md_idx].len);
+		}
+		if (server_len == 0) {
+			if (!sgp) {
+				dev_err(&vscsi->dev, "rdma: ran out of scatter/gather list\n");
+				rc = -EIO;
+				break;
+			}
+			server_ioba = sg_dma_address(sgp);
+			server_len = sg_dma_len(sgp);
+		}
+
+		buf_len = tx_len;
+
+		if (buf_len > client_len)
+			buf_len = client_len;
+
+		if (buf_len > server_len)
+			buf_len = server_len;
+
+		if (buf_len > max_vdma_size)
+			buf_len = max_vdma_size;
+
+		if (dir == DMA_TO_DEVICE) {
+			/* read from client */
+			rc = h_copy_rdma(buf_len,
+					 vscsi->dds.window[REMOTE].liobn,
+					 client_ioba,
+					 vscsi->dds.window[LOCAL].liobn,
+					 server_ioba);
+		} else {
+			/* The h_copy_rdma will cause phyp, running in another
+			 * partition, to read memory, so we need to make sure
+			 * the data has been written out, hence these syncs.
+			 */
+			/* ensure that everything is in memory */
+			isync();
+			/* ensure that memory has been made visible */
+			dma_wmb();
+			rc = h_copy_rdma(buf_len,
+					 vscsi->dds.window[LOCAL].liobn,
+					 server_ioba,
+					 vscsi->dds.window[REMOTE].liobn,
+					 client_ioba);
+		}
+		switch (rc) {
+		case H_SUCCESS:
+			break;
+		case H_PERMISSION:
+		case H_SOURCE_PARM:
+		case H_DEST_PARM:
+			if (connection_broken(vscsi)) {
+				spin_lock_bh(&vscsi->intr_lock);
+				vscsi->flags |=
+					(RESPONSE_Q_DOWN | CLIENT_FAILED);
+				spin_unlock_bh(&vscsi->intr_lock);
+			}
+			dev_err(&vscsi->dev, "rdma: h_copy_rdma failed, rc %ld\n",
+				rc);
+			break;
+
+		default:
+			dev_err(&vscsi->dev, "rdma: unknown error %ld from h_copy_rdma\n",
+				rc);
+			break;
+		}
+
+		if (!rc) {
+			tx_len -= buf_len;
+			if (tx_len) {
+				client_len -= buf_len;
+				if (client_len == 0)
+					md_idx++;
+				else
+					client_ioba += buf_len;
+
+				server_len -= buf_len;
+				if (server_len == 0)
+					sgp = sg_next(sgp);
+				else
+					server_ioba += buf_len;
+			} else {
+				break;
+			}
+		}
+	} while (!rc);
+
+	return rc;
+}
+
+/**
+ * ibmvscsis_handle_crq() - Handle CRQ
+ * @data:	Pointer to our adapter structure
+ *
+ * Read the command elements from the command queue and copy the payloads
+ * associated with the command elements to local memory and execute the
+ * SRP requests.
+ *
+ * Note: this is an edge triggered interrupt. It can not be shared.
+ */
+static void ibmvscsis_handle_crq(unsigned long data)
+{
+	struct scsi_info *vscsi = (struct scsi_info *)data;
+	struct viosrp_crq *crq;
+	long rc;
+	bool ack = true;
+	volatile u8 valid;
+
+	spin_lock_bh(&vscsi->intr_lock);
+
+	dev_dbg(&vscsi->dev, "got interrupt\n");
+
+	/*
+	 * if we are in a path where we are waiting for all pending commands
+	 * to complete because we received a transport event and anything in
+	 * the command queue is for a new connection, do nothing
+	 */
+	if (TARGET_STOP(vscsi)) {
+		vio_enable_interrupts(vscsi->dma_dev);
+
+		dev_dbg(&vscsi->dev, "handle_crq, don't process: flags 0x%x, state 0x%hx\n",
+			vscsi->flags, vscsi->state);
+		spin_unlock_bh(&vscsi->intr_lock);
+		return;
+	}
+
+	rc = vscsi->flags & SCHEDULE_DISCONNECT;
+	crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
+	valid = crq->valid;
+	dma_rmb();
+
+	while (valid) {
+		/*
+		 * These are edege triggered interrupts. After dropping out of
+		 * the while loop, the code must check for work since an
+		 * interrupt could be lost, and an elment be left on the queue,
+		 * hence the label.
+		 */
+cmd_work:
+		vscsi->cmd_q.index =
+			(vscsi->cmd_q.index + 1) & vscsi->cmd_q.mask;
+
+		if (!rc) {
+			rc = ibmvscsis_parse_command(vscsi, crq);
+		} else {
+			if ((uint)crq->valid == VALID_TRANS_EVENT) {
+				/*
+				 * must service the transport layer events even
+				 * in an error state, dont break out until all
+				 * the consecutive transport events have been
+				 * processed
+				 */
+				rc = ibmvscsis_trans_event(vscsi, crq);
+			} else if (vscsi->flags & TRANS_EVENT) {
+				/*
+				 * if a transport event has occurred leave
+				 * everything but transport events on the queue
+				 *
+				 * need to decrement the queue index so we can
+				 * look at the element again
+				 */
+				if (vscsi->cmd_q.index)
+					vscsi->cmd_q.index -= 1;
+				else
+					/*
+					 * index is at 0 it just wrapped.
+					 * have it index last element in q
+					 */
+					vscsi->cmd_q.index = vscsi->cmd_q.mask;
+				break;
+			}
+		}
+
+		crq->valid = INVALIDATE_CMD_RESP_EL;
+
+		crq = vscsi->cmd_q.base_addr + vscsi->cmd_q.index;
+		valid = crq->valid;
+		dma_rmb();
+	}
+
+	if (!rc) {
+		if (ack) {
+			vio_enable_interrupts(vscsi->dma_dev);
+			ack = false;
+			dev_dbg(&vscsi->dev, "handle_crq, reenabling interrupts\n");
+		}
+		valid = crq->valid;
+		dma_rmb();
+		if (valid)
+			goto cmd_work;
+	} else {
+		dev_dbg(&vscsi->dev, "handle_crq, error: flags 0x%x, state 0x%hx, crq index 0x%x\n",
+			vscsi->flags, vscsi->state, vscsi->cmd_q.index);
+	}
+
+	dev_dbg(&vscsi->dev, "Leaving handle_crq: schedule_q empty %d, flags 0x%x, state 0x%hx\n",
+		(int)list_empty(&vscsi->schedule_q), vscsi->flags,
+		vscsi->state);
+
+	spin_unlock_bh(&vscsi->intr_lock);
+}
+
+static int ibmvscsis_probe(struct vio_dev *vdev,
+			   const struct vio_device_id *id)
+{
+	struct scsi_info *vscsi;
+	int rc = 0;
+	long hrc = 0;
+	char wq_name[24];
+
+	vscsi = kzalloc(sizeof(*vscsi), GFP_KERNEL);
+	if (!vscsi) {
+		rc = -ENOMEM;
+		dev_err(&vdev->dev, "probe: allocation of adapter failed\n");
+		return rc;
+	}
+
+	vscsi->dma_dev = vdev;
+	vscsi->dev = vdev->dev;
+	INIT_LIST_HEAD(&vscsi->schedule_q);
+	INIT_LIST_HEAD(&vscsi->waiting_rsp);
+	INIT_LIST_HEAD(&vscsi->active_q);
+
+	snprintf(vscsi->tport.tport_name, IBMVSCSIS_NAMELEN, "%s",
+		 dev_name(&vdev->dev));
+
+	dev_dbg(&vscsi->dev, "probe tport_name: %s\n", vscsi->tport.tport_name);
+
+	rc = read_dma_window(vscsi);
+	if (rc)
+		goto free_adapter;
+	dev_dbg(&vscsi->dev, "Probe: liobn 0x%x, riobn 0x%x\n",
+		vscsi->dds.window[LOCAL].liobn,
+		vscsi->dds.window[REMOTE].liobn);
+
+	snprintf(vscsi->eye, sizeof(vscsi->eye), "VSCSI %s", vdev->name);
+
+	vscsi->dds.unit_id = vdev->unit_address;
+	strscpy(vscsi->dds.partition_name, partition_name,
+		sizeof(vscsi->dds.partition_name));
+	vscsi->dds.partition_num = partition_number;
+
+	spin_lock_bh(&ibmvscsis_dev_lock);
+	list_add_tail(&vscsi->list, &ibmvscsis_dev_list);
+	spin_unlock_bh(&ibmvscsis_dev_lock);
+
+	/*
+	 * TBD: How do we determine # of cmds to request?  Do we know how
+	 * many "children" we have?
+	 */
+	vscsi->request_limit = INITIAL_SRP_LIMIT;
+	rc = srp_target_alloc(&vscsi->target, &vdev->dev, vscsi->request_limit,
+			      SRP_MAX_IU_LEN);
+	if (rc)
+		goto rem_list;
+
+	vscsi->target.ldata = vscsi;
+
+	rc = ibmvscsis_alloc_cmds(vscsi, vscsi->request_limit);
+	if (rc) {
+		dev_err(&vscsi->dev, "alloc_cmds failed, rc %d, num %d\n",
+			rc, vscsi->request_limit);
+		goto free_target;
+	}
+
+	/*
+	 * Note: the lock is used in freeing timers, so must initialize
+	 * first so that ordering in case of error is correct.
+	 */
+	spin_lock_init(&vscsi->intr_lock);
+
+	rc = ibmvscsis_alloctimer(vscsi);
+	if (rc) {
+		dev_err(&vscsi->dev, "probe: alloctimer failed, rc %d\n", rc);
+		goto free_cmds;
+	}
+
+	rc = ibmvscsis_create_command_q(vscsi, 256);
+	if (rc) {
+		dev_err(&vscsi->dev, "probe: create_command_q failed, rc %d\n",
+			rc);
+		goto free_timer;
+	}
+
+	vscsi->map_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!vscsi->map_buf) {
+		rc = -ENOMEM;
+		dev_err(&vscsi->dev, "probe: allocating cmd buffer failed\n");
+		goto destroy_queue;
+	}
+
+	vscsi->map_ioba = dma_map_single(&vdev->dev, vscsi->map_buf, PAGE_SIZE,
+					 DMA_BIDIRECTIONAL);
+	if (dma_mapping_error(&vdev->dev, vscsi->map_ioba)) {
+		rc = -ENOMEM;
+		dev_err(&vscsi->dev, "probe: error mapping command buffer\n");
+		goto free_buf;
+	}
+
+	hrc = h_vioctl(vscsi->dds.unit_id, H_GET_PARTNER_INFO,
+		       (u64)vscsi->map_ioba | ((u64)PAGE_SIZE << 32), 0, 0, 0,
+		       0);
+	if (hrc == H_SUCCESS)
+		vscsi->client_data.partition_number =
+			be64_to_cpu(*(u64 *)vscsi->map_buf);
+	/*
+	 * We expect the VIOCTL to fail if we're configured as "any
+	 * client can connect" and the client isn't activated yet.
+	 * We'll make the call again when he sends an init msg.
+	 */
+	dev_dbg(&vscsi->dev, "probe hrc %ld, client partition num %d\n",
+		hrc, vscsi->client_data.partition_number);
+
+	tasklet_init(&vscsi->work_task, ibmvscsis_handle_crq,
+		     (unsigned long)vscsi);
+
+	init_completion(&vscsi->wait_idle);
+	init_completion(&vscsi->unconfig);
+
+	snprintf(wq_name, 24, "ibmvscsis%s", dev_name(&vdev->dev));
+	vscsi->work_q = create_workqueue(wq_name);
+	if (!vscsi->work_q) {
+		rc = -ENOMEM;
+		dev_err(&vscsi->dev, "create_workqueue failed\n");
+		goto unmap_buf;
+	}
+
+	rc = request_irq(vdev->irq, ibmvscsis_interrupt, 0, "ibmvscsis", vscsi);
+	if (rc) {
+		rc = -EPERM;
+		dev_err(&vscsi->dev, "probe: request_irq failed, rc %d\n", rc);
+		goto destroy_WQ;
+	}
+
+	vscsi->state = WAIT_ENABLED;
+
+	dev_set_drvdata(&vdev->dev, vscsi);
+
+	return 0;
+
+destroy_WQ:
+	destroy_workqueue(vscsi->work_q);
+unmap_buf:
+	dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
+			 DMA_BIDIRECTIONAL);
+free_buf:
+	kfree(vscsi->map_buf);
+destroy_queue:
+	tasklet_kill(&vscsi->work_task);
+	ibmvscsis_unregister_command_q(vscsi);
+	ibmvscsis_destroy_command_q(vscsi);
+free_timer:
+	ibmvscsis_freetimer(vscsi);
+free_cmds:
+	ibmvscsis_free_cmds(vscsi);
+free_target:
+	srp_target_free(&vscsi->target);
+rem_list:
+	spin_lock_bh(&ibmvscsis_dev_lock);
+	list_del(&vscsi->list);
+	spin_unlock_bh(&ibmvscsis_dev_lock);
+free_adapter:
+	kfree(vscsi);
+
+	return rc;
+}
+
+static void ibmvscsis_remove(struct vio_dev *vdev)
+{
+	struct scsi_info *vscsi = dev_get_drvdata(&vdev->dev);
+
+	dev_dbg(&vscsi->dev, "remove (%s)\n", dev_name(&vscsi->dma_dev->dev));
+
+	spin_lock_bh(&vscsi->intr_lock);
+	ibmvscsis_post_disconnect(vscsi, UNCONFIGURING, 0);
+	vscsi->flags |= CFG_SLEEPING;
+	spin_unlock_bh(&vscsi->intr_lock);
+	wait_for_completion(&vscsi->unconfig);
+
+	vio_disable_interrupts(vdev);
+	free_irq(vdev->irq, vscsi);
+	destroy_workqueue(vscsi->work_q);
+	dma_unmap_single(&vdev->dev, vscsi->map_ioba, PAGE_SIZE,
+			 DMA_BIDIRECTIONAL);
+	kfree(vscsi->map_buf);
+	tasklet_kill(&vscsi->work_task);
+	ibmvscsis_destroy_command_q(vscsi);
+	ibmvscsis_freetimer(vscsi);
+	ibmvscsis_free_cmds(vscsi);
+	srp_target_free(&vscsi->target);
+	spin_lock_bh(&ibmvscsis_dev_lock);
+	list_del(&vscsi->list);
+	spin_unlock_bh(&ibmvscsis_dev_lock);
+	kfree(vscsi);
+}
+
+static ssize_t system_id_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "%s\n", system_id);
+}
+
+static ssize_t partition_number_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "%x\n", partition_number);
+}
+
+static ssize_t unit_address_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct scsi_info *vscsi = container_of(dev, struct scsi_info, dev);
+
+	return snprintf(buf, PAGE_SIZE, "%x\n", vscsi->dma_dev->unit_address);
+}
+
+static int ibmvscsis_get_system_info(void)
+{
+	struct device_node *rootdn, *vdevdn;
+	const char *id, *model, *name;
+	const uint *num;
+
+	rootdn = of_find_node_by_path("/");
+	if (!rootdn)
+		return -ENOENT;
+
+	model = of_get_property(rootdn, "model", NULL);
+	id = of_get_property(rootdn, "system-id", NULL);
+	if (model && id)
+		snprintf(system_id, sizeof(system_id), "%s-%s", model, id);
+
+	name = of_get_property(rootdn, "ibm,partition-name", NULL);
+	if (name)
+		strncpy(partition_name, name, sizeof(partition_name));
+
+	num = of_get_property(rootdn, "ibm,partition-no", NULL);
+	if (num)
+		partition_number = of_read_number(num, 1);
+
+	of_node_put(rootdn);
+
+	vdevdn = of_find_node_by_path("/vdevice");
+	if (vdevdn) {
+		const uint *mvds;
+
+		mvds = of_get_property(vdevdn, "ibm,max-virtual-dma-size",
+				       NULL);
+		if (mvds)
+			max_vdma_size = *mvds;
+		of_node_put(vdevdn);
+	}
+
+	return 0;
+}
+
+static char *ibmvscsis_get_fabric_wwn(struct se_portal_group *se_tpg)
+{
+	struct ibmvscsis_tport *tport =
+		container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
+
+	return tport->tport_name;
+}
+
+static u16 ibmvscsis_get_tag(struct se_portal_group *se_tpg)
+{
+	struct ibmvscsis_tport *tport =
+		container_of(se_tpg, struct ibmvscsis_tport, se_tpg);
+
+	return tport->tport_tpgt;
+}
+
+static u32 ibmvscsis_get_default_depth(struct se_portal_group *se_tpg)
+{
+	return 1;
+}
+
+static int ibmvscsis_check_true(struct se_portal_group *se_tpg)
+{
+	return 1;
+}
+
+static int ibmvscsis_check_stop_free(struct se_cmd *se_cmd)
+{
+	return target_put_sess_cmd(se_cmd);
+}
+
+static void ibmvscsis_release_cmd(struct se_cmd *se_cmd)
+{
+	struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
+						 se_cmd);
+	struct scsi_info *vscsi = cmd->adapter;
+
+	spin_lock_bh(&vscsi->intr_lock);
+	/* Remove from active_q */
+	list_move_tail(&cmd->list, &vscsi->waiting_rsp);
+	ibmvscsis_send_messages(vscsi);
+	spin_unlock_bh(&vscsi->intr_lock);
+}
+
+static int ibmvscsis_write_pending(struct se_cmd *se_cmd)
+{
+	struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
+						 se_cmd);
+	struct scsi_info *vscsi = cmd->adapter;
+	struct iu_entry *iue = cmd->iue;
+	int rc;
+
+	/*
+	 * If CLIENT_FAILED OR RESPONSE_Q_DOWN, then just return success
+	 * since LIO can't do anything about it, and we dont want to
+	 * attempt an srp_transfer_data.
+	 */
+	if ((vscsi->flags & (CLIENT_FAILED | RESPONSE_Q_DOWN))) {
+		dev_err(&vscsi->dev, "write_pending failed since: %d\n",
+			vscsi->flags);
+		return -EIO;
+
+	}
+
+	rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma,
+			       1, 1);
+	if (rc) {
+		dev_err(&vscsi->dev, "srp_transfer_data() failed: %d\n", rc);
+		return -EIO;
+	}
+	/*
+	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
+	 * object execution queue.
+	 */
+	target_execute_cmd(se_cmd);
+	return 0;
+}
+
+static int ibmvscsis_queue_data_in(struct se_cmd *se_cmd)
+{
+	struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
+						 se_cmd);
+	struct iu_entry *iue = cmd->iue;
+	struct scsi_info *vscsi = cmd->adapter;
+	uint len = 0;
+	int rc;
+
+	rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma, 1,
+			       1);
+	if (rc) {
+		dev_err(&vscsi->dev, "srp_transfer_data failed: %d\n", rc);
+		se_cmd->scsi_sense_length = 18;
+		memset(se_cmd->sense_buffer, 0, se_cmd->scsi_sense_length);
+		/* Logical Unit Communication Time-out asc/ascq = 0x0801 */
+		scsi_build_sense_buffer(0, se_cmd->sense_buffer, MEDIUM_ERROR,
+					0x08, 0x01);
+	}
+
+	srp_build_response(vscsi, cmd, &len);
+	cmd->rsp.format = SRP_FORMAT;
+	cmd->rsp.len = len;
+
+	return 0;
+}
+
+static int ibmvscsis_queue_status(struct se_cmd *se_cmd)
+{
+	struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
+						 se_cmd);
+	struct scsi_info *vscsi = cmd->adapter;
+	uint len;
+
+	dev_dbg(&vscsi->dev, "queue_status %p\n", se_cmd);
+
+	srp_build_response(vscsi, cmd, &len);
+	cmd->rsp.format = SRP_FORMAT;
+	cmd->rsp.len = len;
+
+	return 0;
+}
+
+static void ibmvscsis_queue_tm_rsp(struct se_cmd *se_cmd)
+{
+	struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
+						 se_cmd);
+	struct scsi_info *vscsi = cmd->adapter;
+	struct ibmvscsis_cmd *cmd_itr;
+	struct iu_entry *iue = iue = cmd->iue;
+	struct srp_tsk_mgmt *srp_tsk = &vio_iu(iue)->srp.tsk_mgmt;
+	u64 tag_to_abort = be64_to_cpu(srp_tsk->task_tag);
+	uint len;
+
+	dev_dbg(&vscsi->dev, "queue_tm_rsp %p, status %d\n",
+		se_cmd, (int)se_cmd->se_tmr_req->response);
+
+	if (srp_tsk->tsk_mgmt_func == SRP_TSK_ABORT_TASK &&
+	    cmd->se_cmd.se_tmr_req->response == TMR_TASK_DOES_NOT_EXIST) {
+		spin_lock_bh(&vscsi->intr_lock);
+		list_for_each_entry(cmd_itr, &vscsi->active_q, list) {
+			if (tag_to_abort == cmd_itr->se_cmd.tag) {
+				cmd_itr->abort_cmd = cmd;
+				cmd->flags |= DELAY_SEND;
+				break;
+			}
+		}
+		spin_unlock_bh(&vscsi->intr_lock);
+	}
+
+	srp_build_response(vscsi, cmd, &len);
+	cmd->rsp.format = SRP_FORMAT;
+	cmd->rsp.len = len;
+}
+
+static void ibmvscsis_aborted_task(struct se_cmd *se_cmd)
+{
+	struct ibmvscsis_cmd *cmd = container_of(se_cmd, struct ibmvscsis_cmd,
+						 se_cmd);
+	struct scsi_info *vscsi = cmd->adapter;
+
+	dev_dbg(&vscsi->dev, "ibmvscsis_aborted_task %p task_tag: %llu\n",
+		se_cmd, se_cmd->tag);
+}
+
+static struct se_wwn *ibmvscsis_make_tport(struct target_fabric_configfs *tf,
+					   struct config_group *group,
+					   const char *name)
+{
+	struct ibmvscsis_tport *tport;
+	struct scsi_info *vscsi;
+
+	tport = ibmvscsis_lookup_port(name);
+	if (tport) {
+		vscsi = container_of(tport, struct scsi_info, tport);
+		tport->tport_proto_id = SCSI_PROTOCOL_SRP;
+		dev_dbg(&vscsi->dev, "make_tport(%s), pointer:%p, tport_id:%x\n",
+			name, tport, tport->tport_proto_id);
+		return &tport->tport_wwn;
+	}
+
+	return ERR_PTR(-EINVAL);
+}
+
+static void ibmvscsis_drop_tport(struct se_wwn *wwn)
+{
+	struct ibmvscsis_tport *tport = container_of(wwn,
+						     struct ibmvscsis_tport,
+						     tport_wwn);
+	struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
+
+	dev_dbg(&vscsi->dev, "drop_tport(%s)\n",
+		config_item_name(&tport->tport_wwn.wwn_group.cg_item));
+}
+
+static struct se_portal_group *ibmvscsis_make_tpg(struct se_wwn *wwn,
+						  const char *name)
+{
+	struct ibmvscsis_tport *tport =
+		container_of(wwn, struct ibmvscsis_tport, tport_wwn);
+	u16 tpgt;
+	int rc;
+
+	if (strstr(name, "tpgt_") != name)
+		return ERR_PTR(-EINVAL);
+	rc = kstrtou16(name + 5, 0, &tpgt);
+	if (rc)
+		return ERR_PTR(rc);
+	tport->tport_tpgt = tpgt;
+
+	tport->releasing = false;
+
+	rc = core_tpg_register(&tport->tport_wwn, &tport->se_tpg,
+			       tport->tport_proto_id);
+	if (rc)
+		return ERR_PTR(rc);
+
+	return &tport->se_tpg;
+}
+
+static void ibmvscsis_drop_tpg(struct se_portal_group *se_tpg)
+{
+	struct ibmvscsis_tport *tport = container_of(se_tpg,
+						     struct ibmvscsis_tport,
+						     se_tpg);
+
+	tport->releasing = true;
+	tport->enabled = false;
+
+	/*
+	 * Release the virtual I_T Nexus for this ibmvscsis TPG
+	 */
+	ibmvscsis_drop_nexus(tport);
+	/*
+	 * Deregister the se_tpg from TCM..
+	 */
+	core_tpg_deregister(se_tpg);
+}
+
+static ssize_t ibmvscsis_wwn_version_show(struct config_item *item,
+					  char *page)
+{
+	return scnprintf(page, PAGE_SIZE, "%s\n", IBMVSCSIS_VERSION);
+}
+CONFIGFS_ATTR_RO(ibmvscsis_wwn_, version);
+
+static struct configfs_attribute *ibmvscsis_wwn_attrs[] = {
+	&ibmvscsis_wwn_attr_version,
+	NULL,
+};
+
+
+static int ibmvscsis_enable_tpg(struct se_portal_group *se_tpg, bool enable)
+{
+	struct ibmvscsis_tport *tport = container_of(se_tpg,
+						     struct ibmvscsis_tport,
+						     se_tpg);
+	struct scsi_info *vscsi = container_of(tport, struct scsi_info, tport);
+	long lrc;
+
+	if (enable) {
+		spin_lock_bh(&vscsi->intr_lock);
+		tport->enabled = true;
+		lrc = ibmvscsis_enable_change_state(vscsi);
+		if (lrc)
+			dev_err(&vscsi->dev, "enable_change_state failed, rc %ld state %d\n",
+				lrc, vscsi->state);
+		spin_unlock_bh(&vscsi->intr_lock);
+	} else {
+		spin_lock_bh(&vscsi->intr_lock);
+		tport->enabled = false;
+		/* This simulates the server going down */
+		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);
+		spin_unlock_bh(&vscsi->intr_lock);
+	}
+
+	return 0;
+}
+
+static const struct target_core_fabric_ops ibmvscsis_ops = {
+	.module				= THIS_MODULE,
+	.fabric_name			= "ibmvscsis",
+	.max_data_sg_nents		= MAX_TXU / PAGE_SIZE,
+	.tpg_get_wwn			= ibmvscsis_get_fabric_wwn,
+	.tpg_get_tag			= ibmvscsis_get_tag,
+	.tpg_get_default_depth		= ibmvscsis_get_default_depth,
+	.tpg_check_demo_mode		= ibmvscsis_check_true,
+	.tpg_check_demo_mode_cache	= ibmvscsis_check_true,
+	.check_stop_free		= ibmvscsis_check_stop_free,
+	.release_cmd			= ibmvscsis_release_cmd,
+	.write_pending			= ibmvscsis_write_pending,
+	.queue_data_in			= ibmvscsis_queue_data_in,
+	.queue_status			= ibmvscsis_queue_status,
+	.queue_tm_rsp			= ibmvscsis_queue_tm_rsp,
+	.aborted_task			= ibmvscsis_aborted_task,
+	/*
+	 * Setup function pointers for logic in target_core_fabric_configfs.c
+	 */
+	.fabric_make_wwn		= ibmvscsis_make_tport,
+	.fabric_drop_wwn		= ibmvscsis_drop_tport,
+	.fabric_make_tpg		= ibmvscsis_make_tpg,
+	.fabric_enable_tpg		= ibmvscsis_enable_tpg,
+	.fabric_drop_tpg		= ibmvscsis_drop_tpg,
+
+	.tfc_wwn_attrs			= ibmvscsis_wwn_attrs,
+};
+
+static void ibmvscsis_dev_release(struct device *dev) {};
+
+static struct device_attribute dev_attr_system_id =
+	__ATTR(system_id, S_IRUGO, system_id_show, NULL);
+
+static struct device_attribute dev_attr_partition_number =
+	__ATTR(partition_number, S_IRUGO, partition_number_show, NULL);
+
+static struct device_attribute dev_attr_unit_address =
+	__ATTR(unit_address, S_IRUGO, unit_address_show, NULL);
+
+static struct attribute *ibmvscsis_dev_attrs[] = {
+	&dev_attr_system_id.attr,
+	&dev_attr_partition_number.attr,
+	&dev_attr_unit_address.attr,
+};
+ATTRIBUTE_GROUPS(ibmvscsis_dev);
+
+static struct class ibmvscsis_class = {
+	.name		= "ibmvscsis",
+	.dev_release	= ibmvscsis_dev_release,
+	.dev_groups	= ibmvscsis_dev_groups,
+};
+
+static const struct vio_device_id ibmvscsis_device_table[] = {
+	{ "v-scsi-host", "IBM,v-scsi-host" },
+	{ "", "" }
+};
+MODULE_DEVICE_TABLE(vio, ibmvscsis_device_table);
+
+static struct vio_driver ibmvscsis_driver = {
+	.name = "ibmvscsis",
+	.id_table = ibmvscsis_device_table,
+	.probe = ibmvscsis_probe,
+	.remove = ibmvscsis_remove,
+};
+
+/*
+ * ibmvscsis_init() - Kernel Module initialization
+ *
+ * Note: vio_register_driver() registers callback functions, and at least one
+ * of those callback functions calls TCM - Linux IO Target Subsystem, thus
+ * the SCSI Target template must be registered before vio_register_driver()
+ * is called.
+ */
+static int __init ibmvscsis_init(void)
+{
+	int rc = 0;
+
+	rc = ibmvscsis_get_system_info();
+	if (rc) {
+		pr_err("rc %d from get_system_info\n", rc);
+		goto out;
+	}
+
+	rc = class_register(&ibmvscsis_class);
+	if (rc) {
+		pr_err("failed class register\n");
+		goto out;
+	}
+
+	rc = target_register_template(&ibmvscsis_ops);
+	if (rc) {
+		pr_err("rc %d from target_register_template\n", rc);
+		goto unregister_class;
+	}
+
+	rc = vio_register_driver(&ibmvscsis_driver);
+	if (rc) {
+		pr_err("rc %d from vio_register_driver\n", rc);
+		goto unregister_target;
+	}
+
+	return 0;
+
+unregister_target:
+	target_unregister_template(&ibmvscsis_ops);
+unregister_class:
+	class_unregister(&ibmvscsis_class);
+out:
+	return rc;
+}
+
+static void __exit ibmvscsis_exit(void)
+{
+	pr_info("Unregister IBM virtual SCSI host driver\n");
+	vio_unregister_driver(&ibmvscsis_driver);
+	target_unregister_template(&ibmvscsis_ops);
+	class_unregister(&ibmvscsis_class);
+}
+
+MODULE_DESCRIPTION("IBMVSCSIS fabric driver");
+MODULE_AUTHOR("Bryant G. Ly and Michael Cyr");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(IBMVSCSIS_VERSION);
+module_init(ibmvscsis_init);
+module_exit(ibmvscsis_exit);
diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h
new file mode 100644
index 0000000000..7ae074e5d7
--- /dev/null
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h
@@ -0,0 +1,362 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*******************************************************************************
+ * IBM Virtual SCSI Target Driver
+ * Copyright (C) 2003-2005 Dave Boutcher (boutcher@us.ibm.com) IBM Corp.
+ *			   Santiago Leon (santil@us.ibm.com) IBM Corp.
+ *			   Linda Xie (lxie@us.ibm.com) IBM Corp.
+ *
+ * Copyright (C) 2005-2011 FUJITA Tomonori <tomof@acm.org>
+ * Copyright (C) 2010 Nicholas A. Bellinger <nab@kernel.org>
+ * Copyright (C) 2016 Bryant G. Ly <bryantly@linux.vnet.ibm.com> IBM Corp.
+ *
+ * Authors: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
+ * Authors: Michael Cyr <mikecyr@linux.vnet.ibm.com>
+ *
+ ****************************************************************************/
+
+#ifndef __H_IBMVSCSI_TGT
+#define __H_IBMVSCSI_TGT
+
+#include <linux/interrupt.h>
+#include "libsrp.h"
+
+#define SYS_ID_NAME_LEN		64
+#define PARTITION_NAMELEN	96
+#define IBMVSCSIS_NAMELEN       32
+
+#define MSG_HI  0
+#define MSG_LOW 1
+
+#define MAX_CMD_Q_PAGES       4
+#define CRQ_PER_PAGE          (PAGE_SIZE / sizeof(struct viosrp_crq))
+/* in terms of number of elements */
+#define DEFAULT_CMD_Q_SIZE    CRQ_PER_PAGE
+#define MAX_CMD_Q_SIZE        (DEFAULT_CMD_Q_SIZE * MAX_CMD_Q_PAGES)
+
+#define SRP_VIOLATION           0x102  /* general error code */
+
+/*
+ * SRP buffer formats defined as of 16.a supported by this driver.
+ */
+#define SUPPORTED_FORMATS  ((SRP_DATA_DESC_DIRECT << 1) | \
+			    (SRP_DATA_DESC_INDIRECT << 1))
+
+#define SCSI_LUN_ADDR_METHOD_FLAT	1
+
+struct dma_window {
+	u32 liobn;	/* Unique per vdevice */
+	u64 tce_base;	/* Physical location of the TCE table */
+	u64 tce_size;	/* Size of the TCE table in bytes */
+};
+
+struct target_dds {
+	u64 unit_id;                /* 64 bit will force alignment */
+#define NUM_DMA_WINDOWS 2
+#define LOCAL  0
+#define REMOTE 1
+	struct dma_window  window[NUM_DMA_WINDOWS];
+
+	/* root node property "ibm,partition-no" */
+	uint partition_num;
+	char partition_name[PARTITION_NAMELEN];
+};
+
+#define MAX_NUM_PORTS        1
+#define MAX_H_COPY_RDMA      (128 * 1024)
+
+#define MAX_EYE   64
+
+/* Return codes */
+#define ADAPT_SUCCESS            0L
+/* choose error codes that do not conflict with PHYP */
+#define ERROR                   -40L
+
+struct format_code {
+	u8 reserved;
+	u8 buffers;
+};
+
+struct client_info {
+#define SRP_VERSION "16.a"
+	char srp_version[8];
+	/* root node property ibm,partition-name */
+	char partition_name[PARTITION_NAMELEN];
+	/* root node property ibm,partition-no */
+	u32 partition_number;
+	/* initially 1 */
+	u32 mad_version;
+	u32 os_type;
+};
+
+/*
+ * Changing this constant changes the number of seconds to wait before
+ * considering the client will never service its queue again.
+ */
+#define SECONDS_TO_CONSIDER_FAILED 30
+/*
+ * These constants set the polling period used to determine if the client
+ * has freed at least one element in the response queue.
+ */
+#define WAIT_SECONDS 1
+#define WAIT_NANO_SECONDS 5000
+#define MAX_TIMER_POPS ((1000000 / WAIT_NANO_SECONDS) * \
+			SECONDS_TO_CONSIDER_FAILED)
+/*
+ * general purpose timer control block
+ * which can be used for multiple functions
+ */
+struct timer_cb {
+	struct hrtimer timer;
+	/*
+	 * how long has it been since the client
+	 * serviced the queue. The variable is incrmented
+	 * in the service_wait_q routine and cleared
+	 * in send messages
+	 */
+	int timer_pops;
+	/* the timer is started */
+	bool started;
+};
+
+struct cmd_queue {
+	/* kva */
+	struct viosrp_crq *base_addr;
+	dma_addr_t crq_token;
+	/* used to maintain index */
+	uint mask;
+	/* current element */
+	uint index;
+	int size;
+};
+
+#define SCSOLNT_RESP_SHIFT	1
+#define UCSOLNT_RESP_SHIFT	2
+
+#define SCSOLNT         BIT(SCSOLNT_RESP_SHIFT)
+#define UCSOLNT         BIT(UCSOLNT_RESP_SHIFT)
+
+enum cmd_type {
+	SCSI_CDB	= 0x01,
+	TASK_MANAGEMENT	= 0x02,
+	/* MAD or addressed to port 0 */
+	ADAPTER_MAD	= 0x04,
+	UNSET_TYPE	= 0x08,
+};
+
+struct iu_rsp {
+	u8 format;
+	u8 sol_not;
+	u16 len;
+	/* tag is just to help client identify cmd, so don't translate be/le */
+	u64 tag;
+};
+
+struct ibmvscsis_cmd {
+	struct list_head list;
+	/* Used for TCM Core operations */
+	struct se_cmd se_cmd;
+	struct iu_entry *iue;
+	struct iu_rsp rsp;
+	struct work_struct work;
+	struct scsi_info *adapter;
+	struct ibmvscsis_cmd *abort_cmd;
+	/* Sense buffer that will be mapped into outgoing status */
+	unsigned char sense_buf[TRANSPORT_SENSE_BUFFER];
+	u64 init_time;
+#define CMD_FAST_FAIL	BIT(0)
+#define DELAY_SEND	BIT(1)
+	u32 flags;
+	char type;
+};
+
+struct ibmvscsis_nexus {
+	struct se_session *se_sess;
+};
+
+struct ibmvscsis_tport {
+	/* SCSI protocol the tport is providing */
+	u8 tport_proto_id;
+	/* ASCII formatted WWPN for SRP Target port */
+	char tport_name[IBMVSCSIS_NAMELEN];
+	/* Returned by ibmvscsis_make_tport() */
+	struct se_wwn tport_wwn;
+	/* Returned by ibmvscsis_make_tpg() */
+	struct se_portal_group se_tpg;
+	/* ibmvscsis port target portal group tag for TCM */
+	u16 tport_tpgt;
+	/* Pointer to TCM session for I_T Nexus */
+	struct ibmvscsis_nexus *ibmv_nexus;
+	bool enabled;
+	bool releasing;
+};
+
+struct scsi_info {
+	struct list_head list;
+	char eye[MAX_EYE];
+
+	/* commands waiting for space on repsonse queue */
+	struct list_head waiting_rsp;
+#define NO_QUEUE                    0x00
+#define WAIT_ENABLED                0X01
+#define WAIT_CONNECTION             0x04
+	/* have established a connection */
+#define CONNECTED                   0x08
+	/* at least one port is processing SRP IU */
+#define SRP_PROCESSING              0x10
+	/* remove request received */
+#define UNCONFIGURING               0x20
+	/* disconnect by letting adapter go idle, no error */
+#define WAIT_IDLE                   0x40
+	/* disconnecting to clear an error */
+#define ERR_DISCONNECT              0x80
+	/* disconnect to clear error state, then come back up */
+#define ERR_DISCONNECT_RECONNECT    0x100
+	/* disconnected after clearing an error */
+#define ERR_DISCONNECTED            0x200
+	/* A series of errors caused unexpected errors */
+#define UNDEFINED                   0x400
+	u16  state;
+	int fast_fail;
+	struct target_dds dds;
+	char *cmd_pool;
+	/* list of free commands */
+	struct list_head free_cmd;
+	/* command elements ready for scheduler */
+	struct list_head schedule_q;
+	/* commands sent to TCM */
+	struct list_head active_q;
+	caddr_t *map_buf;
+	/* ioba of map buffer */
+	dma_addr_t map_ioba;
+	/* allowable number of outstanding SRP requests */
+	int request_limit;
+	/* extra credit */
+	int credit;
+	/* outstanding transactions against credit limit */
+	int debit;
+
+	/* allow only one outstanding mad request */
+#define PROCESSING_MAD                0x00002
+	/* Waiting to go idle */
+#define WAIT_FOR_IDLE		      0x00004
+	/* H_REG_CRQ called */
+#define CRQ_CLOSED                    0x00010
+	/* detected that client has failed */
+#define CLIENT_FAILED                 0x00040
+	/* detected that transport event occurred */
+#define TRANS_EVENT                   0x00080
+	/* don't attempt to send anything to the client */
+#define RESPONSE_Q_DOWN               0x00100
+	/* request made to schedule disconnect handler */
+#define SCHEDULE_DISCONNECT           0x00400
+	/* disconnect handler is scheduled */
+#define DISCONNECT_SCHEDULED          0x00800
+	/* remove function is sleeping */
+#define CFG_SLEEPING                  0x01000
+	/* Register for Prepare for Suspend Transport Events */
+#define PREP_FOR_SUSPEND_ENABLED      0x02000
+	/* Prepare for Suspend event sent */
+#define PREP_FOR_SUSPEND_PENDING      0x04000
+	/* Resume from Suspend event sent */
+#define PREP_FOR_SUSPEND_ABORTED      0x08000
+	/* Prepare for Suspend event overwrote another CRQ entry */
+#define PREP_FOR_SUSPEND_OVERWRITE    0x10000
+	u32 flags;
+	/* adapter lock */
+	spinlock_t intr_lock;
+	/* information needed to manage command queue */
+	struct cmd_queue cmd_q;
+	/* used in hcall to copy response back into srp buffer */
+	u64  empty_iu_id;
+	/* used in crq, to tag what iu the response is for */
+	u64  empty_iu_tag;
+	uint new_state;
+	uint resume_state;
+	/* control block for the response queue timer */
+	struct timer_cb rsp_q_timer;
+	/* keep last client to enable proper accounting */
+	struct client_info client_data;
+	/* what can this client do */
+	u32 client_cap;
+	/*
+	 * The following two fields capture state and flag changes that
+	 * can occur when the lock is given up.  In the orginal design,
+	 * the lock was held during calls into phyp;
+	 * however, phyp did not meet PAPR architecture.  This is
+	 * a work around.
+	 */
+	u16  phyp_acr_state;
+	u32 phyp_acr_flags;
+
+	struct workqueue_struct *work_q;
+	struct completion wait_idle;
+	struct completion unconfig;
+	struct device dev;
+	struct vio_dev *dma_dev;
+	struct srp_target target;
+	struct ibmvscsis_tport tport;
+	struct tasklet_struct work_task;
+	struct work_struct proc_work;
+};
+
+/*
+ * Provide a constant that allows software to detect the adapter is
+ * disconnecting from the client from one of several states.
+ */
+#define IS_DISCONNECTING (UNCONFIGURING | ERR_DISCONNECT_RECONNECT | \
+			  ERR_DISCONNECT)
+
+/*
+ * Provide a constant that can be used with interrupt handling that
+ * essentially lets the interrupt handler know that all requests should
+ * be thrown out,
+ */
+#define DONT_PROCESS_STATE (IS_DISCONNECTING | UNDEFINED | \
+			    ERR_DISCONNECTED  | WAIT_IDLE)
+
+/*
+ * If any of these flag bits are set then do not allow the interrupt
+ * handler to schedule the off level handler.
+ */
+#define BLOCK (DISCONNECT_SCHEDULED)
+
+/* State and transition events that stop the interrupt handler */
+#define TARGET_STOP(VSCSI) (long)(((VSCSI)->state & DONT_PROCESS_STATE) | \
+				  ((VSCSI)->flags & BLOCK))
+
+#define PREP_FOR_SUSPEND_FLAGS  (PREP_FOR_SUSPEND_ENABLED | \
+				 PREP_FOR_SUSPEND_PENDING | \
+				 PREP_FOR_SUSPEND_ABORTED | \
+				 PREP_FOR_SUSPEND_OVERWRITE)
+
+/* flag bit that are not reset during disconnect */
+#define PRESERVE_FLAG_FIELDS (PREP_FOR_SUSPEND_FLAGS)
+
+#define vio_iu(IUE) ((union viosrp_iu *)((IUE)->sbuf->buf))
+
+#define READ_CMD(cdb)	(((cdb)[0] & 0x1F) == 8)
+#define WRITE_CMD(cdb)	(((cdb)[0] & 0x1F) == 0xA)
+
+#ifndef H_GET_PARTNER_INFO
+#define H_GET_PARTNER_INFO              0x0000000000000008LL
+#endif
+#ifndef H_ENABLE_PREPARE_FOR_SUSPEND
+#define H_ENABLE_PREPARE_FOR_SUSPEND    0x000000000000001DLL
+#endif
+#ifndef H_READY_FOR_SUSPEND
+#define H_READY_FOR_SUSPEND             0x000000000000001ELL
+#endif
+
+
+#define h_copy_rdma(l, sa, sb, da, db) \
+		plpar_hcall_norets(H_COPY_RDMA, l, sa, sb, da, db)
+#define h_vioctl(u, o, a, u1, u2, u3, u4) \
+		plpar_hcall_norets(H_VIOCTL, u, o, a, u1, u2)
+#define h_reg_crq(ua, tok, sz) \
+		plpar_hcall_norets(H_REG_CRQ, ua, tok, sz)
+#define h_free_crq(ua) \
+		plpar_hcall_norets(H_FREE_CRQ, ua)
+#define h_send_crq(ua, d1, d2) \
+		plpar_hcall_norets(H_SEND_CRQ, ua, d1, d2)
+
+#endif
diff --git a/drivers/scsi/ibmvscsi_tgt/libsrp.c b/drivers/scsi/ibmvscsi_tgt/libsrp.c
new file mode 100644
index 0000000000..8a0e28aec9
--- /dev/null
+++ b/drivers/scsi/ibmvscsi_tgt/libsrp.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*******************************************************************************
+ * SCSI RDMA Protocol lib functions
+ *
+ * Copyright (C) 2006 FUJITA Tomonori <tomof@acm.org>
+ * Copyright (C) 2016 Bryant G. Ly <bryantly@linux.vnet.ibm.com> IBM Corp.
+ *
+ ***********************************************************************/
+
+#define pr_fmt(fmt)	"libsrp: " fmt
+
+#include <linux/printk.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/kfifo.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <scsi/srp.h>
+#include <target/target_core_base.h>
+#include "libsrp.h"
+#include "ibmvscsi_tgt.h"
+
+static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
+			     struct srp_buf **ring)
+{
+	struct iu_entry *iue;
+	int i;
+
+	q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
+	if (!q->pool)
+		return -ENOMEM;
+	q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
+	if (!q->items)
+		goto free_pool;
+
+	spin_lock_init(&q->lock);
+	kfifo_init(&q->queue, (void *)q->pool, max * sizeof(void *));
+
+	for (i = 0, iue = q->items; i < max; i++) {
+		kfifo_in(&q->queue, (void *)&iue, sizeof(void *));
+		iue->sbuf = ring[i];
+		iue++;
+	}
+	return 0;
+
+free_pool:
+	kfree(q->pool);
+	return -ENOMEM;
+}
+
+static void srp_iu_pool_free(struct srp_queue *q)
+{
+	kfree(q->items);
+	kfree(q->pool);
+}
+
+static struct srp_buf **srp_ring_alloc(struct device *dev,
+				       size_t max, size_t size)
+{
+	struct srp_buf **ring;
+	int i;
+
+	ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL);
+	if (!ring)
+		return NULL;
+
+	for (i = 0; i < max; i++) {
+		ring[i] = kzalloc(sizeof(*ring[i]), GFP_KERNEL);
+		if (!ring[i])
+			goto out;
+		ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma,
+						  GFP_KERNEL);
+		if (!ring[i]->buf)
+			goto out;
+	}
+	return ring;
+
+out:
+	for (i = 0; i < max && ring[i]; i++) {
+		if (ring[i]->buf) {
+			dma_free_coherent(dev, size, ring[i]->buf,
+					  ring[i]->dma);
+		}
+		kfree(ring[i]);
+	}
+	kfree(ring);
+
+	return NULL;
+}
+
+static void srp_ring_free(struct device *dev, struct srp_buf **ring,
+			  size_t max, size_t size)
+{
+	int i;
+
+	for (i = 0; i < max; i++) {
+		dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
+		kfree(ring[i]);
+	}
+	kfree(ring);
+}
+
+int srp_target_alloc(struct srp_target *target, struct device *dev,
+		     size_t nr, size_t iu_size)
+{
+	int err;
+
+	spin_lock_init(&target->lock);
+
+	target->dev = dev;
+
+	target->srp_iu_size = iu_size;
+	target->rx_ring_size = nr;
+	target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size);
+	if (!target->rx_ring)
+		return -ENOMEM;
+	err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring);
+	if (err)
+		goto free_ring;
+
+	dev_set_drvdata(target->dev, target);
+	return 0;
+
+free_ring:
+	srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
+	return -ENOMEM;
+}
+
+void srp_target_free(struct srp_target *target)
+{
+	dev_set_drvdata(target->dev, NULL);
+	srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size,
+		      target->srp_iu_size);
+	srp_iu_pool_free(&target->iu_queue);
+}
+
+struct iu_entry *srp_iu_get(struct srp_target *target)
+{
+	struct iu_entry *iue = NULL;
+
+	if (kfifo_out_locked(&target->iu_queue.queue, (void *)&iue,
+			     sizeof(void *),
+			     &target->iu_queue.lock) != sizeof(void *)) {
+		WARN_ONCE(1, "unexpected fifo state");
+		return NULL;
+	}
+	if (!iue)
+		return iue;
+	iue->target = target;
+	iue->flags = 0;
+	return iue;
+}
+
+void srp_iu_put(struct iu_entry *iue)
+{
+	kfifo_in_locked(&iue->target->iu_queue.queue, (void *)&iue,
+			sizeof(void *), &iue->target->iu_queue.lock);
+}
+
+static int srp_direct_data(struct ibmvscsis_cmd *cmd, struct srp_direct_buf *md,
+			   enum dma_data_direction dir, srp_rdma_t rdma_io,
+			   int dma_map, int ext_desc)
+{
+	struct iu_entry *iue = NULL;
+	struct scatterlist *sg = NULL;
+	int err, nsg = 0, len;
+
+	if (dma_map) {
+		iue = cmd->iue;
+		sg = cmd->se_cmd.t_data_sg;
+		nsg = dma_map_sg(iue->target->dev, sg, cmd->se_cmd.t_data_nents,
+				 DMA_BIDIRECTIONAL);
+		if (!nsg) {
+			pr_err("fail to map %p %d\n", iue,
+			       cmd->se_cmd.t_data_nents);
+			return 0;
+		}
+		len = min(cmd->se_cmd.data_length, be32_to_cpu(md->len));
+	} else {
+		len = be32_to_cpu(md->len);
+	}
+
+	err = rdma_io(cmd, sg, nsg, md, 1, dir, len);
+
+	if (dma_map)
+		dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
+
+	return err;
+}
+
+static int srp_indirect_data(struct ibmvscsis_cmd *cmd, struct srp_cmd *srp_cmd,
+			     struct srp_indirect_buf *id,
+			     enum dma_data_direction dir, srp_rdma_t rdma_io,
+			     int dma_map, int ext_desc)
+{
+	struct iu_entry *iue = NULL;
+	struct srp_direct_buf *md = NULL;
+	struct scatterlist dummy, *sg = NULL;
+	dma_addr_t token = 0;
+	int err = 0;
+	int nmd, nsg = 0, len;
+
+	if (dma_map || ext_desc) {
+		iue = cmd->iue;
+		sg = cmd->se_cmd.t_data_sg;
+	}
+
+	nmd = be32_to_cpu(id->table_desc.len) / sizeof(struct srp_direct_buf);
+
+	if ((dir == DMA_FROM_DEVICE && nmd == srp_cmd->data_in_desc_cnt) ||
+	    (dir == DMA_TO_DEVICE && nmd == srp_cmd->data_out_desc_cnt)) {
+		md = &id->desc_list[0];
+		goto rdma;
+	}
+
+	if (ext_desc && dma_map) {
+		md = dma_alloc_coherent(iue->target->dev,
+					be32_to_cpu(id->table_desc.len),
+					&token, GFP_KERNEL);
+		if (!md) {
+			pr_err("Can't get dma memory %u\n",
+			       be32_to_cpu(id->table_desc.len));
+			return -ENOMEM;
+		}
+
+		sg_init_one(&dummy, md, be32_to_cpu(id->table_desc.len));
+		sg_dma_address(&dummy) = token;
+		sg_dma_len(&dummy) = be32_to_cpu(id->table_desc.len);
+		err = rdma_io(cmd, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
+			      be32_to_cpu(id->table_desc.len));
+		if (err) {
+			pr_err("Error copying indirect table %d\n", err);
+			goto free_mem;
+		}
+	} else {
+		pr_err("This command uses external indirect buffer\n");
+		return -EINVAL;
+	}
+
+rdma:
+	if (dma_map) {
+		nsg = dma_map_sg(iue->target->dev, sg, cmd->se_cmd.t_data_nents,
+				 DMA_BIDIRECTIONAL);
+		if (!nsg) {
+			pr_err("fail to map %p %d\n", iue,
+			       cmd->se_cmd.t_data_nents);
+			err = -EIO;
+			goto free_mem;
+		}
+		len = min(cmd->se_cmd.data_length, be32_to_cpu(id->len));
+	} else {
+		len = be32_to_cpu(id->len);
+	}
+
+	err = rdma_io(cmd, sg, nsg, md, nmd, dir, len);
+
+	if (dma_map)
+		dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
+
+free_mem:
+	if (token && dma_map) {
+		dma_free_coherent(iue->target->dev,
+				  be32_to_cpu(id->table_desc.len), md, token);
+	}
+	return err;
+}
+
+static int data_out_desc_size(struct srp_cmd *cmd)
+{
+	int size = 0;
+	u8 fmt = cmd->buf_fmt >> 4;
+
+	switch (fmt) {
+	case SRP_NO_DATA_DESC:
+		break;
+	case SRP_DATA_DESC_DIRECT:
+		size = sizeof(struct srp_direct_buf);
+		break;
+	case SRP_DATA_DESC_INDIRECT:
+		size = sizeof(struct srp_indirect_buf) +
+			sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
+		break;
+	default:
+		pr_err("client error. Invalid data_out_format %x\n", fmt);
+		break;
+	}
+	return size;
+}
+
+/*
+ * TODO: this can be called multiple times for a single command if it
+ * has very long data.
+ */
+int srp_transfer_data(struct ibmvscsis_cmd *cmd, struct srp_cmd *srp_cmd,
+		      srp_rdma_t rdma_io, int dma_map, int ext_desc)
+{
+	struct srp_direct_buf *md;
+	struct srp_indirect_buf *id;
+	enum dma_data_direction dir;
+	int offset, err = 0;
+	u8 format;
+
+	if (!cmd->se_cmd.t_data_nents)
+		return 0;
+
+	offset = srp_cmd->add_cdb_len & ~3;
+
+	dir = srp_cmd_direction(srp_cmd);
+	if (dir == DMA_FROM_DEVICE)
+		offset += data_out_desc_size(srp_cmd);
+
+	if (dir == DMA_TO_DEVICE)
+		format = srp_cmd->buf_fmt >> 4;
+	else
+		format = srp_cmd->buf_fmt & ((1U << 4) - 1);
+
+	switch (format) {
+	case SRP_NO_DATA_DESC:
+		break;
+	case SRP_DATA_DESC_DIRECT:
+		md = (struct srp_direct_buf *)(srp_cmd->add_data + offset);
+		err = srp_direct_data(cmd, md, dir, rdma_io, dma_map, ext_desc);
+		break;
+	case SRP_DATA_DESC_INDIRECT:
+		id = (struct srp_indirect_buf *)(srp_cmd->add_data + offset);
+		err = srp_indirect_data(cmd, srp_cmd, id, dir, rdma_io, dma_map,
+					ext_desc);
+		break;
+	default:
+		pr_err("Unknown format %d %x\n", dir, format);
+		err = -EINVAL;
+	}
+
+	return err;
+}
+
+u64 srp_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
+{
+	struct srp_direct_buf *md;
+	struct srp_indirect_buf *id;
+	u64 len = 0;
+	uint offset = cmd->add_cdb_len & ~3;
+	u8 fmt;
+
+	if (dir == DMA_TO_DEVICE) {
+		fmt = cmd->buf_fmt >> 4;
+	} else {
+		fmt = cmd->buf_fmt & ((1U << 4) - 1);
+		offset += data_out_desc_size(cmd);
+	}
+
+	switch (fmt) {
+	case SRP_NO_DATA_DESC:
+		break;
+	case SRP_DATA_DESC_DIRECT:
+		md = (struct srp_direct_buf *)(cmd->add_data + offset);
+		len = be32_to_cpu(md->len);
+		break;
+	case SRP_DATA_DESC_INDIRECT:
+		id = (struct srp_indirect_buf *)(cmd->add_data + offset);
+		len = be32_to_cpu(id->len);
+		break;
+	default:
+		pr_err("invalid data format %x\n", fmt);
+		break;
+	}
+	return len;
+}
+
+int srp_get_desc_table(struct srp_cmd *srp_cmd, enum dma_data_direction *dir,
+		       u64 *data_len)
+{
+	struct srp_indirect_buf *idb;
+	struct srp_direct_buf *db;
+	uint add_cdb_offset;
+	int rc;
+
+	/*
+	 * The pointer computations below will only be compiled correctly
+	 * if srp_cmd::add_data is declared as s8*, u8*, s8[] or u8[], so check
+	 * whether srp_cmd::add_data has been declared as a byte pointer.
+	 */
+	BUILD_BUG_ON(!__same_type(srp_cmd->add_data[0], (s8)0)
+		     && !__same_type(srp_cmd->add_data[0], (u8)0));
+
+	BUG_ON(!dir);
+	BUG_ON(!data_len);
+
+	rc = 0;
+	*data_len = 0;
+
+	*dir = DMA_NONE;
+
+	if (srp_cmd->buf_fmt & 0xf)
+		*dir = DMA_FROM_DEVICE;
+	else if (srp_cmd->buf_fmt >> 4)
+		*dir = DMA_TO_DEVICE;
+
+	add_cdb_offset = srp_cmd->add_cdb_len & ~3;
+	if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_DIRECT) ||
+	    ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_DIRECT)) {
+		db = (struct srp_direct_buf *)(srp_cmd->add_data
+					       + add_cdb_offset);
+		*data_len = be32_to_cpu(db->len);
+	} else if (((srp_cmd->buf_fmt & 0xf) == SRP_DATA_DESC_INDIRECT) ||
+		   ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_INDIRECT)) {
+		idb = (struct srp_indirect_buf *)(srp_cmd->add_data
+						  + add_cdb_offset);
+
+		*data_len = be32_to_cpu(idb->len);
+	}
+	return rc;
+}
+
+MODULE_DESCRIPTION("SCSI RDMA Protocol lib functions");
+MODULE_AUTHOR("FUJITA Tomonori");
+MODULE_LICENSE("GPL");
diff --git a/drivers/scsi/ibmvscsi_tgt/libsrp.h b/drivers/scsi/ibmvscsi_tgt/libsrp.h
new file mode 100644
index 0000000000..832606ae29
--- /dev/null
+++ b/drivers/scsi/ibmvscsi_tgt/libsrp.h
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LIBSRP_H__
+#define __LIBSRP_H__
+
+#include <linux/list.h>
+#include <linux/kfifo.h>
+#include <scsi/srp.h>
+
+enum srp_valid {
+	INVALIDATE_CMD_RESP_EL = 0,
+	VALID_CMD_RESP_EL = 0x80,
+	VALID_INIT_MSG = 0xC0,
+	VALID_TRANS_EVENT = 0xFF
+};
+
+enum srp_format {
+	SRP_FORMAT = 1,
+	MAD_FORMAT = 2,
+	OS400_FORMAT = 3,
+	AIX_FORMAT = 4,
+	LINUX_FORMAT = 5,
+	MESSAGE_IN_CRQ = 6
+};
+
+enum srp_init_msg {
+	INIT_MSG = 1,
+	INIT_COMPLETE_MSG = 2
+};
+
+enum srp_trans_event {
+	UNUSED_FORMAT = 0,
+	PARTNER_FAILED = 1,
+	PARTNER_DEREGISTER = 2,
+	MIGRATED = 6,
+	PREPARE_FOR_SUSPEND = 9,
+	RESUME_FROM_SUSP = 0xA
+};
+
+enum srp_status {
+	CRQ_ENTRY_OVERWRITTEN = 0x20,
+	HEADER_DESCRIPTOR = 0xF1,
+	PING = 0xF5,
+	PING_RESPONSE = 0xF6
+};
+
+enum srp_mad_version {
+	MAD_VERSION_1 = 1
+};
+
+enum srp_os_type {
+	OS400 = 1,
+	LINUX = 2,
+	AIX = 3,
+	OFW = 4
+};
+
+enum srp_task_attributes {
+	SRP_SIMPLE_TASK = 0,
+	SRP_HEAD_TASK = 1,
+	SRP_ORDERED_TASK = 2,
+	SRP_ACA_TASK = 4
+};
+
+enum {
+	SRP_TASK_MANAGEMENT_FUNCTION_COMPLETE           = 0,
+	SRP_REQUEST_FIELDS_INVALID                      = 2,
+	SRP_TASK_MANAGEMENT_FUNCTION_NOT_SUPPORTED      = 4,
+	SRP_TASK_MANAGEMENT_FUNCTION_FAILED             = 5
+};
+
+struct srp_buf {
+	dma_addr_t dma;
+	void *buf;
+};
+
+struct srp_queue {
+	void *pool;
+	void *items;
+	struct kfifo queue;
+	spinlock_t lock;
+};
+
+struct srp_target {
+	struct device *dev;
+
+	spinlock_t lock;
+	struct list_head cmd_queue;
+
+	size_t srp_iu_size;
+	struct srp_queue iu_queue;
+	size_t rx_ring_size;
+	struct srp_buf **rx_ring;
+
+	void *ldata;
+};
+
+struct iu_entry {
+	struct srp_target *target;
+
+	struct list_head ilist;
+	dma_addr_t remote_token;
+	unsigned long flags;
+
+	struct srp_buf *sbuf;
+	u16 iu_len;
+};
+
+struct ibmvscsis_cmd;
+
+typedef int (srp_rdma_t)(struct ibmvscsis_cmd *, struct scatterlist *, int,
+			 struct srp_direct_buf *, int,
+			 enum dma_data_direction, unsigned int);
+int srp_target_alloc(struct srp_target *, struct device *, size_t, size_t);
+void srp_target_free(struct srp_target *);
+struct iu_entry *srp_iu_get(struct srp_target *);
+void srp_iu_put(struct iu_entry *);
+int srp_transfer_data(struct ibmvscsis_cmd *, struct srp_cmd *,
+		      srp_rdma_t, int, int);
+u64 srp_data_length(struct srp_cmd *cmd, enum dma_data_direction dir);
+int srp_get_desc_table(struct srp_cmd *srp_cmd, enum dma_data_direction *dir,
+		       u64 *data_len);
+static inline int srp_cmd_direction(struct srp_cmd *cmd)
+{
+	return (cmd->buf_fmt >> 4) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+}
+
+#endif