RDMA/amso1100: Add driver for Ammasso 1100 RNIC

Add a driver for the Ammasso 1100 gigabit ethernet RNIC.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 975 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/amso1100/c2_qp.c b/drivers/infiniband/hw/amso1100/c2_qp.c
new file mode 100644
index 000000000000..12261132b077
--- /dev/null
+++ b/drivers/infiniband/hw/amso1100/c2_qp.c
@@ -0,0 +1,975 @@
+/*
+ * Copyright (c) 2004 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Cisco Systems. All rights reserved.
+ * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2004 Voltaire, Inc. All rights reserved.
+ * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include "c2.h"
+#include "c2_vq.h"
+#include "c2_status.h"
+
+#define C2_MAX_ORD_PER_QP 128
+#define C2_MAX_IRD_PER_QP 128
+
+#define C2_HINT_MAKE(q_index, hint_count) (((q_index) << 16) | hint_count)
+#define C2_HINT_GET_INDEX(hint) (((hint) & 0x7FFF0000) >> 16)
+#define C2_HINT_GET_COUNT(hint) ((hint) & 0x0000FFFF)
+
+#define NO_SUPPORT -1
+static const u8 c2_opcode[] = {
+	[IB_WR_SEND] = C2_WR_TYPE_SEND,
+	[IB_WR_SEND_WITH_IMM] = NO_SUPPORT,
+	[IB_WR_RDMA_WRITE] = C2_WR_TYPE_RDMA_WRITE,
+	[IB_WR_RDMA_WRITE_WITH_IMM] = NO_SUPPORT,
+	[IB_WR_RDMA_READ] = C2_WR_TYPE_RDMA_READ,
+	[IB_WR_ATOMIC_CMP_AND_SWP] = NO_SUPPORT,
+	[IB_WR_ATOMIC_FETCH_AND_ADD] = NO_SUPPORT,
+};
+
+static int to_c2_state(enum ib_qp_state ib_state)
+{
+	switch (ib_state) {
+	case IB_QPS_RESET:
+		return C2_QP_STATE_IDLE;
+	case IB_QPS_RTS:
+		return C2_QP_STATE_RTS;
+	case IB_QPS_SQD:
+		return C2_QP_STATE_CLOSING;
+	case IB_QPS_SQE:
+		return C2_QP_STATE_CLOSING;
+	case IB_QPS_ERR:
+		return C2_QP_STATE_ERROR;
+	default:
+		return -1;
+	}
+}
+
+static int to_ib_state(enum c2_qp_state c2_state)
+{
+	switch (c2_state) {
+	case C2_QP_STATE_IDLE:
+		return IB_QPS_RESET;
+	case C2_QP_STATE_CONNECTING:
+		return IB_QPS_RTR;
+	case C2_QP_STATE_RTS:
+		return IB_QPS_RTS;
+	case C2_QP_STATE_CLOSING:
+		return IB_QPS_SQD;
+	case C2_QP_STATE_ERROR:
+		return IB_QPS_ERR;
+	case C2_QP_STATE_TERMINATE:
+		return IB_QPS_SQE;
+	default:
+		return -1;
+	}
+}
+
+static const char *to_ib_state_str(int ib_state)
+{
+	static const char *state_str[] = {
+		"IB_QPS_RESET",
+		"IB_QPS_INIT",
+		"IB_QPS_RTR",
+		"IB_QPS_RTS",
+		"IB_QPS_SQD",
+		"IB_QPS_SQE",
+		"IB_QPS_ERR"
+	};
+	if (ib_state < IB_QPS_RESET ||
+	    ib_state > IB_QPS_ERR)
+		return "<invalid IB QP state>";
+
+	ib_state -= IB_QPS_RESET;
+	return state_str[ib_state];
+}
+
+void c2_set_qp_state(struct c2_qp *qp, int c2_state)
+{
+	int new_state = to_ib_state(c2_state);
+
+	pr_debug("%s: qp[%p] state modify %s --> %s\n",
+	       __FUNCTION__,
+		qp,
+		to_ib_state_str(qp->state),
+		to_ib_state_str(new_state));
+	qp->state = new_state;
+}
+
+#define C2_QP_NO_ATTR_CHANGE 0xFFFFFFFF
+
+int c2_qp_modify(struct c2_dev *c2dev, struct c2_qp *qp,
+		 struct ib_qp_attr *attr, int attr_mask)
+{
+	struct c2wr_qp_modify_req wr;
+	struct c2wr_qp_modify_rep *reply;
+	struct c2_vq_req *vq_req;
+	unsigned long flags;
+	u8 next_state;
+	int err;
+
+	pr_debug("%s:%d qp=%p, %s --> %s\n",
+		__FUNCTION__, __LINE__,
+		qp,
+		to_ib_state_str(qp->state),
+		to_ib_state_str(attr->qp_state));
+
+	vq_req = vq_req_alloc(c2dev);
+	if (!vq_req)
+		return -ENOMEM;
+
+	c2_wr_set_id(&wr, CCWR_QP_MODIFY);
+	wr.hdr.context = (unsigned long) vq_req;
+	wr.rnic_handle = c2dev->adapter_handle;
+	wr.qp_handle = qp->adapter_handle;
+	wr.ord = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+	wr.ird = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+	wr.sq_depth = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+	wr.rq_depth = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+
+	if (attr_mask & IB_QP_STATE) {
+		/* Ensure the state is valid */
+		if (attr->qp_state < 0 || attr->qp_state > IB_QPS_ERR)
+			return -EINVAL;
+
+		wr.next_qp_state = cpu_to_be32(to_c2_state(attr->qp_state));
+
+		if (attr->qp_state == IB_QPS_ERR) {
+			spin_lock_irqsave(&qp->lock, flags);
+			if (qp->cm_id && qp->state == IB_QPS_RTS) {
+				pr_debug("Generating CLOSE event for QP-->ERR, "
+					"qp=%p, cm_id=%p\n",qp,qp->cm_id);
+				/* Generate an CLOSE event */
+				vq_req->cm_id = qp->cm_id;
+				vq_req->event = IW_CM_EVENT_CLOSE;
+			}
+			spin_unlock_irqrestore(&qp->lock, flags);
+		}
+		next_state =  attr->qp_state;
+
+	} else if (attr_mask & IB_QP_CUR_STATE) {
+
+		if (attr->cur_qp_state != IB_QPS_RTR &&
+		    attr->cur_qp_state != IB_QPS_RTS &&
+		    attr->cur_qp_state != IB_QPS_SQD &&
+		    attr->cur_qp_state != IB_QPS_SQE)
+			return -EINVAL;
+		else
+			wr.next_qp_state =
+			    cpu_to_be32(to_c2_state(attr->cur_qp_state));
+
+		next_state = attr->cur_qp_state;
+
+	} else {
+		err = 0;
+		goto bail0;
+	}
+
+	/* reference the request struct */
+	vq_req_get(c2dev, vq_req);
+
+	err = vq_send_wr(c2dev, (union c2wr *) & wr);
+	if (err) {
+		vq_req_put(c2dev, vq_req);
+		goto bail0;
+	}
+
+	err = vq_wait_for_reply(c2dev, vq_req);
+	if (err)
+		goto bail0;
+
+	reply = (struct c2wr_qp_modify_rep *) (unsigned long) vq_req->reply_msg;
+	if (!reply) {
+		err = -ENOMEM;
+		goto bail0;
+	}
+
+	err = c2_errno(reply);
+	if (!err)
+		qp->state = next_state;
+#ifdef DEBUG
+	else
+		pr_debug("%s: c2_errno=%d\n", __FUNCTION__, err);
+#endif
+	/*
+	 * If we're going to error and generating the event here, then
+	 * we need to remove the reference because there will be no
+	 * close event generated by the adapter
+	*/
+	spin_lock_irqsave(&qp->lock, flags);
+	if (vq_req->event==IW_CM_EVENT_CLOSE && qp->cm_id) {
+		qp->cm_id->rem_ref(qp->cm_id);
+		qp->cm_id = NULL;
+	}
+	spin_unlock_irqrestore(&qp->lock, flags);
+
+	vq_repbuf_free(c2dev, reply);
+      bail0:
+	vq_req_free(c2dev, vq_req);
+
+	pr_debug("%s:%d qp=%p, cur_state=%s\n",
+		__FUNCTION__, __LINE__,
+		qp,
+		to_ib_state_str(qp->state));
+	return err;
+}
+
+int c2_qp_set_read_limits(struct c2_dev *c2dev, struct c2_qp *qp,
+			  int ord, int ird)
+{
+	struct c2wr_qp_modify_req wr;
+	struct c2wr_qp_modify_rep *reply;
+	struct c2_vq_req *vq_req;
+	int err;
+
+	vq_req = vq_req_alloc(c2dev);
+	if (!vq_req)
+		return -ENOMEM;
+
+	c2_wr_set_id(&wr, CCWR_QP_MODIFY);
+	wr.hdr.context = (unsigned long) vq_req;
+	wr.rnic_handle = c2dev->adapter_handle;
+	wr.qp_handle = qp->adapter_handle;
+	wr.ord = cpu_to_be32(ord);
+	wr.ird = cpu_to_be32(ird);
+	wr.sq_depth = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+	wr.rq_depth = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+	wr.next_qp_state = cpu_to_be32(C2_QP_NO_ATTR_CHANGE);
+
+	/* reference the request struct */
+	vq_req_get(c2dev, vq_req);
+
+	err = vq_send_wr(c2dev, (union c2wr *) & wr);
+	if (err) {
+		vq_req_put(c2dev, vq_req);
+		goto bail0;
+	}
+
+	err = vq_wait_for_reply(c2dev, vq_req);
+	if (err)
+		goto bail0;
+
+	reply = (struct c2wr_qp_modify_rep *) (unsigned long)
+		vq_req->reply_msg;
+	if (!reply) {
+		err = -ENOMEM;
+		goto bail0;
+	}
+
+	err = c2_errno(reply);
+	vq_repbuf_free(c2dev, reply);
+      bail0:
+	vq_req_free(c2dev, vq_req);
+	return err;
+}
+
+static int destroy_qp(struct c2_dev *c2dev, struct c2_qp *qp)
+{
+	struct c2_vq_req *vq_req;
+	struct c2wr_qp_destroy_req wr;
+	struct c2wr_qp_destroy_rep *reply;
+	unsigned long flags;
+	int err;
+
+	/*
+	 * Allocate a verb request message
+	 */
+	vq_req = vq_req_alloc(c2dev);
+	if (!vq_req) {
+		return -ENOMEM;
+	}
+
+	/*
+	 * Initialize the WR
+	 */
+	c2_wr_set_id(&wr, CCWR_QP_DESTROY);
+	wr.hdr.context = (unsigned long) vq_req;
+	wr.rnic_handle = c2dev->adapter_handle;
+	wr.qp_handle = qp->adapter_handle;
+
+	/*
+	 * reference the request struct.  dereferenced in the int handler.
+	 */
+	vq_req_get(c2dev, vq_req);
+
+	spin_lock_irqsave(&qp->lock, flags);
+	if (qp->cm_id && qp->state == IB_QPS_RTS) {
+		pr_debug("destroy_qp: generating CLOSE event for QP-->ERR, "
+			"qp=%p, cm_id=%p\n",qp,qp->cm_id);
+		/* Generate an CLOSE event */
+		vq_req->qp = qp;
+		vq_req->cm_id = qp->cm_id;
+		vq_req->event = IW_CM_EVENT_CLOSE;
+	}
+	spin_unlock_irqrestore(&qp->lock, flags);
+
+	/*
+	 * Send WR to adapter
+	 */
+	err = vq_send_wr(c2dev, (union c2wr *) & wr);
+	if (err) {
+		vq_req_put(c2dev, vq_req);
+		goto bail0;
+	}
+
+	/*
+	 * Wait for reply from adapter
+	 */
+	err = vq_wait_for_reply(c2dev, vq_req);
+	if (err) {
+		goto bail0;
+	}
+
+	/*
+	 * Process reply
+	 */
+	reply = (struct c2wr_qp_destroy_rep *) (unsigned long) (vq_req->reply_msg);
+	if (!reply) {
+		err = -ENOMEM;
+		goto bail0;
+	}
+
+	spin_lock_irqsave(&qp->lock, flags);
+	if (qp->cm_id) {
+		qp->cm_id->rem_ref(qp->cm_id);
+		qp->cm_id = NULL;
+	}
+	spin_unlock_irqrestore(&qp->lock, flags);
+
+	vq_repbuf_free(c2dev, reply);
+      bail0:
+	vq_req_free(c2dev, vq_req);
+	return err;
+}
+
+static int c2_alloc_qpn(struct c2_dev *c2dev, struct c2_qp *qp)
+{
+	int ret;
+
+        do {
+		spin_lock_irq(&c2dev->qp_table.lock);
+		ret = idr_get_new_above(&c2dev->qp_table.idr, qp,
+					c2dev->qp_table.last++, &qp->qpn);
+		spin_unlock_irq(&c2dev->qp_table.lock);
+        } while ((ret == -EAGAIN) &&
+	 	 idr_pre_get(&c2dev->qp_table.idr, GFP_KERNEL));
+	return ret;
+}
+
+static void c2_free_qpn(struct c2_dev *c2dev, int qpn)
+{
+	spin_lock_irq(&c2dev->qp_table.lock);
+	idr_remove(&c2dev->qp_table.idr, qpn);
+	spin_unlock_irq(&c2dev->qp_table.lock);
+}
+
+struct c2_qp *c2_find_qpn(struct c2_dev *c2dev, int qpn)
+{
+	unsigned long flags;
+	struct c2_qp *qp;
+
+	spin_lock_irqsave(&c2dev->qp_table.lock, flags);
+	qp = idr_find(&c2dev->qp_table.idr, qpn);
+	spin_unlock_irqrestore(&c2dev->qp_table.lock, flags);
+	return qp;
+}
+
+int c2_alloc_qp(struct c2_dev *c2dev,
+		struct c2_pd *pd,
+		struct ib_qp_init_attr *qp_attrs, struct c2_qp *qp)
+{
+	struct c2wr_qp_create_req wr;
+	struct c2wr_qp_create_rep *reply;
+	struct c2_vq_req *vq_req;
+	struct c2_cq *send_cq = to_c2cq(qp_attrs->send_cq);
+	struct c2_cq *recv_cq = to_c2cq(qp_attrs->recv_cq);
+	unsigned long peer_pa;
+	u32 q_size, msg_size, mmap_size;
+	void __iomem *mmap;
+	int err;
+
+	err = c2_alloc_qpn(c2dev, qp);
+	if (err)
+		return err;
+	qp->ibqp.qp_num = qp->qpn;
+	qp->ibqp.qp_type = IB_QPT_RC;
+
+	/* Allocate the SQ and RQ shared pointers */
+	qp->sq_mq.shared = c2_alloc_mqsp(c2dev, c2dev->kern_mqsp_pool,
+					 &qp->sq_mq.shared_dma, GFP_KERNEL);
+	if (!qp->sq_mq.shared) {
+		err = -ENOMEM;
+		goto bail0;
+	}
+
+	qp->rq_mq.shared = c2_alloc_mqsp(c2dev, c2dev->kern_mqsp_pool,
+					 &qp->rq_mq.shared_dma, GFP_KERNEL);
+	if (!qp->rq_mq.shared) {
+		err = -ENOMEM;
+		goto bail1;
+	}
+
+	/* Allocate the verbs request */
+	vq_req = vq_req_alloc(c2dev);
+	if (vq_req == NULL) {
+		err = -ENOMEM;
+		goto bail2;
+	}
+
+	/* Initialize the work request */
+	memset(&wr, 0, sizeof(wr));
+	c2_wr_set_id(&wr, CCWR_QP_CREATE);
+	wr.hdr.context = (unsigned long) vq_req;
+	wr.rnic_handle = c2dev->adapter_handle;
+	wr.sq_cq_handle = send_cq->adapter_handle;
+	wr.rq_cq_handle = recv_cq->adapter_handle;
+	wr.sq_depth = cpu_to_be32(qp_attrs->cap.max_send_wr + 1);
+	wr.rq_depth = cpu_to_be32(qp_attrs->cap.max_recv_wr + 1);
+	wr.srq_handle = 0;
+	wr.flags = cpu_to_be32(QP_RDMA_READ | QP_RDMA_WRITE | QP_MW_BIND |
+			       QP_ZERO_STAG | QP_RDMA_READ_RESPONSE);
+	wr.send_sgl_depth = cpu_to_be32(qp_attrs->cap.max_send_sge);
+	wr.recv_sgl_depth = cpu_to_be32(qp_attrs->cap.max_recv_sge);
+	wr.rdma_write_sgl_depth = cpu_to_be32(qp_attrs->cap.max_send_sge);
+	wr.shared_sq_ht = cpu_to_be64(qp->sq_mq.shared_dma);
+	wr.shared_rq_ht = cpu_to_be64(qp->rq_mq.shared_dma);
+	wr.ord = cpu_to_be32(C2_MAX_ORD_PER_QP);
+	wr.ird = cpu_to_be32(C2_MAX_IRD_PER_QP);
+	wr.pd_id = pd->pd_id;
+	wr.user_context = (unsigned long) qp;
+
+	vq_req_get(c2dev, vq_req);
+
+	/* Send the WR to the adapter */
+	err = vq_send_wr(c2dev, (union c2wr *) & wr);
+	if (err) {
+		vq_req_put(c2dev, vq_req);
+		goto bail3;
+	}
+
+	/* Wait for the verb reply  */
+	err = vq_wait_for_reply(c2dev, vq_req);
+	if (err) {
+		goto bail3;
+	}
+
+	/* Process the reply */
+	reply = (struct c2wr_qp_create_rep *) (unsigned long) (vq_req->reply_msg);
+	if (!reply) {
+		err = -ENOMEM;
+		goto bail3;
+	}
+
+	if ((err = c2_wr_get_result(reply)) != 0) {
+		goto bail4;
+	}
+
+	/* Fill in the kernel QP struct */
+	atomic_set(&qp->refcount, 1);
+	qp->adapter_handle = reply->qp_handle;
+	qp->state = IB_QPS_RESET;
+	qp->send_sgl_depth = qp_attrs->cap.max_send_sge;
+	qp->rdma_write_sgl_depth = qp_attrs->cap.max_send_sge;
+	qp->recv_sgl_depth = qp_attrs->cap.max_recv_sge;
+
+	/* Initialize the SQ MQ */
+	q_size = be32_to_cpu(reply->sq_depth);
+	msg_size = be32_to_cpu(reply->sq_msg_size);
+	peer_pa = c2dev->pa + be32_to_cpu(reply->sq_mq_start);
+	mmap_size = PAGE_ALIGN(sizeof(struct c2_mq_shared) + msg_size * q_size);
+	mmap = ioremap_nocache(peer_pa, mmap_size);
+	if (!mmap) {
+		err = -ENOMEM;
+		goto bail5;
+	}
+
+	c2_mq_req_init(&qp->sq_mq,
+		       be32_to_cpu(reply->sq_mq_index),
+		       q_size,
+		       msg_size,
+		       mmap + sizeof(struct c2_mq_shared),	/* pool start */
+		       mmap,				/* peer */
+		       C2_MQ_ADAPTER_TARGET);
+
+	/* Initialize the RQ mq */
+	q_size = be32_to_cpu(reply->rq_depth);
+	msg_size = be32_to_cpu(reply->rq_msg_size);
+	peer_pa = c2dev->pa + be32_to_cpu(reply->rq_mq_start);
+	mmap_size = PAGE_ALIGN(sizeof(struct c2_mq_shared) + msg_size * q_size);
+	mmap = ioremap_nocache(peer_pa, mmap_size);
+	if (!mmap) {
+		err = -ENOMEM;
+		goto bail6;
+	}
+
+	c2_mq_req_init(&qp->rq_mq,
+		       be32_to_cpu(reply->rq_mq_index),
+		       q_size,
+		       msg_size,
+		       mmap + sizeof(struct c2_mq_shared),	/* pool start */
+		       mmap,				/* peer */
+		       C2_MQ_ADAPTER_TARGET);
+
+	vq_repbuf_free(c2dev, reply);
+	vq_req_free(c2dev, vq_req);
+
+	return 0;
+
+      bail6:
+	iounmap(qp->sq_mq.peer);
+      bail5:
+	destroy_qp(c2dev, qp);
+      bail4:
+	vq_repbuf_free(c2dev, reply);
+      bail3:
+	vq_req_free(c2dev, vq_req);
+      bail2:
+	c2_free_mqsp(qp->rq_mq.shared);
+      bail1:
+	c2_free_mqsp(qp->sq_mq.shared);
+      bail0:
+	c2_free_qpn(c2dev, qp->qpn);
+	return err;
+}
+
+void c2_free_qp(struct c2_dev *c2dev, struct c2_qp *qp)
+{
+	struct c2_cq *send_cq;
+	struct c2_cq *recv_cq;
+
+	send_cq = to_c2cq(qp->ibqp.send_cq);
+	recv_cq = to_c2cq(qp->ibqp.recv_cq);
+
+	/*
+	 * Lock CQs here, so that CQ polling code can do QP lookup
+	 * without taking a lock.
+	 */
+	spin_lock_irq(&send_cq->lock);
+	if (send_cq != recv_cq)
+		spin_lock(&recv_cq->lock);
+
+	c2_free_qpn(c2dev, qp->qpn);
+
+	if (send_cq != recv_cq)
+		spin_unlock(&recv_cq->lock);
+	spin_unlock_irq(&send_cq->lock);
+
+	/*
+	 * Destory qp in the rnic...
+	 */
+	destroy_qp(c2dev, qp);
+
+	/*
+	 * Mark any unreaped CQEs as null and void.
+	 */
+	c2_cq_clean(c2dev, qp, send_cq->cqn);
+	if (send_cq != recv_cq)
+		c2_cq_clean(c2dev, qp, recv_cq->cqn);
+	/*
+	 * Unmap the MQs and return the shared pointers
+	 * to the message pool.
+	 */
+	iounmap(qp->sq_mq.peer);
+	iounmap(qp->rq_mq.peer);
+	c2_free_mqsp(qp->sq_mq.shared);
+	c2_free_mqsp(qp->rq_mq.shared);
+
+	atomic_dec(&qp->refcount);
+	wait_event(qp->wait, !atomic_read(&qp->refcount));
+}
+
+/*
+ * Function: move_sgl
+ *
+ * Description:
+ * Move an SGL from the user's work request struct into a CCIL Work Request
+ * message, swapping to WR byte order and ensure the total length doesn't
+ * overflow.
+ *
+ * IN:
+ * dst		- ptr to CCIL Work Request message SGL memory.
+ * src		- ptr to the consumers SGL memory.
+ *
+ * OUT: none
+ *
+ * Return:
+ * CCIL status codes.
+ */
+static int
+move_sgl(struct c2_data_addr * dst, struct ib_sge *src, int count, u32 * p_len,
+	 u8 * actual_count)
+{
+	u32 tot = 0;		/* running total */
+	u8 acount = 0;		/* running total non-0 len sge's */
+
+	while (count > 0) {
+		/*
+		 * If the addition of this SGE causes the
+		 * total SGL length to exceed 2^32-1, then
+		 * fail-n-bail.
+		 *
+		 * If the current total plus the next element length
+		 * wraps, then it will go negative and be less than the
+		 * current total...
+		 */
+		if ((tot + src->length) < tot) {
+			return -EINVAL;
+		}
+		/*
+		 * Bug: 1456 (as well as 1498 & 1643)
+		 * Skip over any sge's supplied with len=0
+		 */
+		if (src->length) {
+			tot += src->length;
+			dst->stag = cpu_to_be32(src->lkey);
+			dst->to = cpu_to_be64(src->addr);
+			dst->length = cpu_to_be32(src->length);
+			dst++;
+			acount++;
+		}
+		src++;
+		count--;
+	}
+
+	if (acount == 0) {
+		/*
+		 * Bug: 1476 (as well as 1498, 1456 and 1643)
+		 * Setup the SGL in the WR to make it easier for the RNIC.
+		 * This way, the FW doesn't have to deal with special cases.
+		 * Setting length=0 should be sufficient.
+		 */
+		dst->stag = 0;
+		dst->to = 0;
+		dst->length = 0;
+	}
+
+	*p_len = tot;
+	*actual_count = acount;
+	return 0;
+}
+
+/*
+ * Function: c2_activity (private function)
+ *
+ * Description:
+ * Post an mq index to the host->adapter activity fifo.
+ *
+ * IN:
+ * c2dev	- ptr to c2dev structure
+ * mq_index	- mq index to post
+ * shared	- value most recently written to shared
+ *
+ * OUT:
+ *
+ * Return:
+ * none
+ */
+static inline void c2_activity(struct c2_dev *c2dev, u32 mq_index, u16 shared)
+{
+	/*
+	 * First read the register to see if the FIFO is full, and if so,
+	 * spin until it's not.  This isn't perfect -- there is no
+	 * synchronization among the clients of the register, but in
+	 * practice it prevents multiple CPU from hammering the bus
+	 * with PCI RETRY. Note that when this does happen, the card
+	 * cannot get on the bus and the card and system hang in a
+	 * deadlock -- thus the need for this code. [TOT]
+	 */
+	while (readl(c2dev->regs + PCI_BAR0_ADAPTER_HINT) & 0x80000000) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(0);
+	}
+
+	__raw_writel(C2_HINT_MAKE(mq_index, shared),
+		     c2dev->regs + PCI_BAR0_ADAPTER_HINT);
+}
+
+/*
+ * Function: qp_wr_post
+ *
+ * Description:
+ * This in-line function allocates a MQ msg, then moves the host-copy of
+ * the completed WR into msg.  Then it posts the message.
+ *
+ * IN:
+ * q		- ptr to user MQ.
+ * wr		- ptr to host-copy of the WR.
+ * qp		- ptr to user qp
+ * size		- Number of bytes to post.  Assumed to be divisible by 4.
+ *
+ * OUT: none
+ *
+ * Return:
+ * CCIL status codes.
+ */
+static int qp_wr_post(struct c2_mq *q, union c2wr * wr, struct c2_qp *qp, u32 size)
+{
+	union c2wr *msg;
+
+	msg = c2_mq_alloc(q);
+	if (msg == NULL) {
+		return -EINVAL;
+	}
+#ifdef CCMSGMAGIC
+	((c2wr_hdr_t *) wr)->magic = cpu_to_be32(CCWR_MAGIC);
+#endif
+
+	/*
+	 * Since all header fields in the WR are the same as the
+	 * CQE, set the following so the adapter need not.
+	 */
+	c2_wr_set_result(wr, CCERR_PENDING);
+
+	/*
+	 * Copy the wr down to the adapter
+	 */
+	memcpy((void *) msg, (void *) wr, size);
+
+	c2_mq_produce(q);
+	return 0;
+}
+
+
+int c2_post_send(struct ib_qp *ibqp, struct ib_send_wr *ib_wr,
+		 struct ib_send_wr **bad_wr)
+{
+	struct c2_dev *c2dev = to_c2dev(ibqp->device);
+	struct c2_qp *qp = to_c2qp(ibqp);
+	union c2wr wr;
+	int err = 0;
+
+	u32 flags;
+	u32 tot_len;
+	u8 actual_sge_count;
+	u32 msg_size;
+
+	if (qp->state > IB_QPS_RTS)
+		return -EINVAL;
+
+	while (ib_wr) {
+
+		flags = 0;
+		wr.sqwr.sq_hdr.user_hdr.hdr.context = ib_wr->wr_id;
+		if (ib_wr->send_flags & IB_SEND_SIGNALED) {
+			flags |= SQ_SIGNALED;
+		}
+
+		switch (ib_wr->opcode) {
+		case IB_WR_SEND:
+			if (ib_wr->send_flags & IB_SEND_SOLICITED) {
+				c2_wr_set_id(&wr, C2_WR_TYPE_SEND_SE);
+				msg_size = sizeof(struct c2wr_send_req);
+			} else {
+				c2_wr_set_id(&wr, C2_WR_TYPE_SEND);
+				msg_size = sizeof(struct c2wr_send_req);
+			}
+
+			wr.sqwr.send.remote_stag = 0;
+			msg_size += sizeof(struct c2_data_addr) * ib_wr->num_sge;
+			if (ib_wr->num_sge > qp->send_sgl_depth) {
+				err = -EINVAL;
+				break;
+			}
+			if (ib_wr->send_flags & IB_SEND_FENCE) {
+				flags |= SQ_READ_FENCE;
+			}
+			err = move_sgl((struct c2_data_addr *) & (wr.sqwr.send.data),
+				       ib_wr->sg_list,
+				       ib_wr->num_sge,
+				       &tot_len, &actual_sge_count);
+			wr.sqwr.send.sge_len = cpu_to_be32(tot_len);
+			c2_wr_set_sge_count(&wr, actual_sge_count);
+			break;
+		case IB_WR_RDMA_WRITE:
+			c2_wr_set_id(&wr, C2_WR_TYPE_RDMA_WRITE);
+			msg_size = sizeof(struct c2wr_rdma_write_req) +
+			    (sizeof(struct c2_data_addr) * ib_wr->num_sge);
+			if (ib_wr->num_sge > qp->rdma_write_sgl_depth) {
+				err = -EINVAL;
+				break;
+			}
+			if (ib_wr->send_flags & IB_SEND_FENCE) {
+				flags |= SQ_READ_FENCE;
+			}
+			wr.sqwr.rdma_write.remote_stag =
+			    cpu_to_be32(ib_wr->wr.rdma.rkey);
+			wr.sqwr.rdma_write.remote_to =
+			    cpu_to_be64(ib_wr->wr.rdma.remote_addr);
+			err = move_sgl((struct c2_data_addr *)
+				       & (wr.sqwr.rdma_write.data),
+				       ib_wr->sg_list,
+				       ib_wr->num_sge,
+				       &tot_len, &actual_sge_count);
+			wr.sqwr.rdma_write.sge_len = cpu_to_be32(tot_len);
+			c2_wr_set_sge_count(&wr, actual_sge_count);
+			break;
+		case IB_WR_RDMA_READ:
+			c2_wr_set_id(&wr, C2_WR_TYPE_RDMA_READ);
+			msg_size = sizeof(struct c2wr_rdma_read_req);
+
+			/* IWarp only suppots 1 sge for RDMA reads */
+			if (ib_wr->num_sge > 1) {
+				err = -EINVAL;
+				break;
+			}
+
+			/*
+			 * Move the local and remote stag/to/len into the WR.
+			 */
+			wr.sqwr.rdma_read.local_stag =
+			    cpu_to_be32(ib_wr->sg_list->lkey);
+			wr.sqwr.rdma_read.local_to =
+			    cpu_to_be64(ib_wr->sg_list->addr);
+			wr.sqwr.rdma_read.remote_stag =
+			    cpu_to_be32(ib_wr->wr.rdma.rkey);
+			wr.sqwr.rdma_read.remote_to =
+			    cpu_to_be64(ib_wr->wr.rdma.remote_addr);
+			wr.sqwr.rdma_read.length =
+			    cpu_to_be32(ib_wr->sg_list->length);
+			break;
+		default:
+			/* error */
+			msg_size = 0;
+			err = -EINVAL;
+			break;
+		}
+
+		/*
+		 * If we had an error on the last wr build, then
+		 * break out.  Possible errors include bogus WR
+		 * type, and a bogus SGL length...
+		 */
+		if (err) {
+			break;
+		}
+
+		/*
+		 * Store flags
+		 */
+		c2_wr_set_flags(&wr, flags);
+
+		/*
+		 * Post the puppy!
+		 */
+		err = qp_wr_post(&qp->sq_mq, &wr, qp, msg_size);
+		if (err) {
+			break;
+		}
+
+		/*
+		 * Enqueue mq index to activity FIFO.
+		 */
+		c2_activity(c2dev, qp->sq_mq.index, qp->sq_mq.hint_count);
+
+		ib_wr = ib_wr->next;
+	}
+
+	if (err)
+		*bad_wr = ib_wr;
+	return err;
+}
+
+int c2_post_receive(struct ib_qp *ibqp, struct ib_recv_wr *ib_wr,
+		    struct ib_recv_wr **bad_wr)
+{
+	struct c2_dev *c2dev = to_c2dev(ibqp->device);
+	struct c2_qp *qp = to_c2qp(ibqp);
+	union c2wr wr;
+	int err = 0;
+
+	if (qp->state > IB_QPS_RTS)
+		return -EINVAL;
+
+	/*
+	 * Try and post each work request
+	 */
+	while (ib_wr) {
+		u32 tot_len;
+		u8 actual_sge_count;
+
+		if (ib_wr->num_sge > qp->recv_sgl_depth) {
+			err = -EINVAL;
+			break;
+		}
+
+		/*
+		 * Create local host-copy of the WR
+		 */
+		wr.rqwr.rq_hdr.user_hdr.hdr.context = ib_wr->wr_id;
+		c2_wr_set_id(&wr, CCWR_RECV);
+		c2_wr_set_flags(&wr, 0);
+
+		/* sge_count is limited to eight bits. */
+		BUG_ON(ib_wr->num_sge >= 256);
+		err = move_sgl((struct c2_data_addr *) & (wr.rqwr.data),
+			       ib_wr->sg_list,
+			       ib_wr->num_sge, &tot_len, &actual_sge_count);
+		c2_wr_set_sge_count(&wr, actual_sge_count);
+
+		/*
+		 * If we had an error on the last wr build, then
+		 * break out.  Possible errors include bogus WR
+		 * type, and a bogus SGL length...
+		 */
+		if (err) {
+			break;
+		}
+
+		err = qp_wr_post(&qp->rq_mq, &wr, qp, qp->rq_mq.msg_size);
+		if (err) {
+			break;
+		}
+
+		/*
+		 * Enqueue mq index to activity FIFO
+		 */
+		c2_activity(c2dev, qp->rq_mq.index, qp->rq_mq.hint_count);
+
+		ib_wr = ib_wr->next;
+	}
+
+	if (err)
+		*bad_wr = ib_wr;
+	return err;
+}
+
+void __devinit c2_init_qp_table(struct c2_dev *c2dev)
+{
+	spin_lock_init(&c2dev->qp_table.lock);
+	idr_init(&c2dev->qp_table.idr);
+}
+
+void __devexit c2_cleanup_qp_table(struct c2_dev *c2dev)
+{
+	idr_destroy(&c2dev->qp_table.idr);
+}