Initial import

1 files changed, 1366 insertions, 0 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
new file mode 100644
index 000000000..f609c1c2d
--- /dev/null
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -0,0 +1,1366 @@
+/*
+ * Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved.
+ * Copyright (c) 2005-2007 Network Appliance, 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 BSD-type
+ * 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.
+ *
+ *      Neither the name of the Network Appliance, Inc. nor the names of
+ *      its contributors may be used to endorse or promote products
+ *      derived from this software without specific prior written
+ *      permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Author: Tom Tucker <tom@opengridcomputing.com>
+ */
+
+#include <linux/sunrpc/svc_xprt.h>
+#include <linux/sunrpc/debug.h>
+#include <linux/sunrpc/rpc_rdma.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/rdma_cm.h>
+#include <linux/sunrpc/svc_rdma.h>
+#include <linux/export.h>
+#include "xprt_rdma.h"
+
+#define RPCDBG_FACILITY	RPCDBG_SVCXPRT
+
+static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
+					struct net *net,
+					struct sockaddr *sa, int salen,
+					int flags);
+static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt);
+static void svc_rdma_release_rqst(struct svc_rqst *);
+static void dto_tasklet_func(unsigned long data);
+static void svc_rdma_detach(struct svc_xprt *xprt);
+static void svc_rdma_free(struct svc_xprt *xprt);
+static int svc_rdma_has_wspace(struct svc_xprt *xprt);
+static int svc_rdma_secure_port(struct svc_rqst *);
+static void rq_cq_reap(struct svcxprt_rdma *xprt);
+static void sq_cq_reap(struct svcxprt_rdma *xprt);
+
+static DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL);
+static DEFINE_SPINLOCK(dto_lock);
+static LIST_HEAD(dto_xprt_q);
+
+static struct svc_xprt_ops svc_rdma_ops = {
+	.xpo_create = svc_rdma_create,
+	.xpo_recvfrom = svc_rdma_recvfrom,
+	.xpo_sendto = svc_rdma_sendto,
+	.xpo_release_rqst = svc_rdma_release_rqst,
+	.xpo_detach = svc_rdma_detach,
+	.xpo_free = svc_rdma_free,
+	.xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr,
+	.xpo_has_wspace = svc_rdma_has_wspace,
+	.xpo_accept = svc_rdma_accept,
+	.xpo_secure_port = svc_rdma_secure_port,
+};
+
+struct svc_xprt_class svc_rdma_class = {
+	.xcl_name = "rdma",
+	.xcl_owner = THIS_MODULE,
+	.xcl_ops = &svc_rdma_ops,
+	.xcl_max_payload = RPCSVC_MAXPAYLOAD_RDMA,
+	.xcl_ident = XPRT_TRANSPORT_RDMA,
+};
+
+struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt)
+{
+	struct svc_rdma_op_ctxt *ctxt;
+
+	while (1) {
+		ctxt = kmem_cache_alloc(svc_rdma_ctxt_cachep, GFP_KERNEL);
+		if (ctxt)
+			break;
+		schedule_timeout_uninterruptible(msecs_to_jiffies(500));
+	}
+	ctxt->xprt = xprt;
+	INIT_LIST_HEAD(&ctxt->dto_q);
+	ctxt->count = 0;
+	ctxt->frmr = NULL;
+	atomic_inc(&xprt->sc_ctxt_used);
+	return ctxt;
+}
+
+void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt)
+{
+	struct svcxprt_rdma *xprt = ctxt->xprt;
+	int i;
+	for (i = 0; i < ctxt->count && ctxt->sge[i].length; i++) {
+		/*
+		 * Unmap the DMA addr in the SGE if the lkey matches
+		 * the sc_dma_lkey, otherwise, ignore it since it is
+		 * an FRMR lkey and will be unmapped later when the
+		 * last WR that uses it completes.
+		 */
+		if (ctxt->sge[i].lkey == xprt->sc_dma_lkey) {
+			atomic_dec(&xprt->sc_dma_used);
+			ib_dma_unmap_page(xprt->sc_cm_id->device,
+					    ctxt->sge[i].addr,
+					    ctxt->sge[i].length,
+					    ctxt->direction);
+		}
+	}
+}
+
+void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages)
+{
+	struct svcxprt_rdma *xprt;
+	int i;
+
+	xprt = ctxt->xprt;
+	if (free_pages)
+		for (i = 0; i < ctxt->count; i++)
+			put_page(ctxt->pages[i]);
+
+	kmem_cache_free(svc_rdma_ctxt_cachep, ctxt);
+	atomic_dec(&xprt->sc_ctxt_used);
+}
+
+/*
+ * Temporary NFS req mappings are shared across all transport
+ * instances. These are short lived and should be bounded by the number
+ * of concurrent server threads * depth of the SQ.
+ */
+struct svc_rdma_req_map *svc_rdma_get_req_map(void)
+{
+	struct svc_rdma_req_map *map;
+	while (1) {
+		map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL);
+		if (map)
+			break;
+		schedule_timeout_uninterruptible(msecs_to_jiffies(500));
+	}
+	map->count = 0;
+	return map;
+}
+
+void svc_rdma_put_req_map(struct svc_rdma_req_map *map)
+{
+	kmem_cache_free(svc_rdma_map_cachep, map);
+}
+
+/* ib_cq event handler */
+static void cq_event_handler(struct ib_event *event, void *context)
+{
+	struct svc_xprt *xprt = context;
+	dprintk("svcrdma: received CQ event id=%d, context=%p\n",
+		event->event, context);
+	set_bit(XPT_CLOSE, &xprt->xpt_flags);
+}
+
+/* QP event handler */
+static void qp_event_handler(struct ib_event *event, void *context)
+{
+	struct svc_xprt *xprt = context;
+
+	switch (event->event) {
+	/* These are considered benign events */
+	case IB_EVENT_PATH_MIG:
+	case IB_EVENT_COMM_EST:
+	case IB_EVENT_SQ_DRAINED:
+	case IB_EVENT_QP_LAST_WQE_REACHED:
+		dprintk("svcrdma: QP event %d received for QP=%p\n",
+			event->event, event->element.qp);
+		break;
+	/* These are considered fatal events */
+	case IB_EVENT_PATH_MIG_ERR:
+	case IB_EVENT_QP_FATAL:
+	case IB_EVENT_QP_REQ_ERR:
+	case IB_EVENT_QP_ACCESS_ERR:
+	case IB_EVENT_DEVICE_FATAL:
+	default:
+		dprintk("svcrdma: QP ERROR event %d received for QP=%p, "
+			"closing transport\n",
+			event->event, event->element.qp);
+		set_bit(XPT_CLOSE, &xprt->xpt_flags);
+		break;
+	}
+}
+
+/*
+ * Data Transfer Operation Tasklet
+ *
+ * Walks a list of transports with I/O pending, removing entries as
+ * they are added to the server's I/O pending list. Two bits indicate
+ * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave
+ * spinlock that serializes access to the transport list with the RQ
+ * and SQ interrupt handlers.
+ */
+static void dto_tasklet_func(unsigned long data)
+{
+	struct svcxprt_rdma *xprt;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dto_lock, flags);
+	while (!list_empty(&dto_xprt_q)) {
+		xprt = list_entry(dto_xprt_q.next,
+				  struct svcxprt_rdma, sc_dto_q);
+		list_del_init(&xprt->sc_dto_q);
+		spin_unlock_irqrestore(&dto_lock, flags);
+
+		rq_cq_reap(xprt);
+		sq_cq_reap(xprt);
+
+		svc_xprt_put(&xprt->sc_xprt);
+		spin_lock_irqsave(&dto_lock, flags);
+	}
+	spin_unlock_irqrestore(&dto_lock, flags);
+}
+
+/*
+ * Receive Queue Completion Handler
+ *
+ * Since an RQ completion handler is called on interrupt context, we
+ * need to defer the handling of the I/O to a tasklet
+ */
+static void rq_comp_handler(struct ib_cq *cq, void *cq_context)
+{
+	struct svcxprt_rdma *xprt = cq_context;
+	unsigned long flags;
+
+	/* Guard against unconditional flush call for destroyed QP */
+	if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
+		return;
+
+	/*
+	 * Set the bit regardless of whether or not it's on the list
+	 * because it may be on the list already due to an SQ
+	 * completion.
+	 */
+	set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags);
+
+	/*
+	 * If this transport is not already on the DTO transport queue,
+	 * add it
+	 */
+	spin_lock_irqsave(&dto_lock, flags);
+	if (list_empty(&xprt->sc_dto_q)) {
+		svc_xprt_get(&xprt->sc_xprt);
+		list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
+	}
+	spin_unlock_irqrestore(&dto_lock, flags);
+
+	/* Tasklet does all the work to avoid irqsave locks. */
+	tasklet_schedule(&dto_tasklet);
+}
+
+/*
+ * rq_cq_reap - Process the RQ CQ.
+ *
+ * Take all completing WC off the CQE and enqueue the associated DTO
+ * context on the dto_q for the transport.
+ *
+ * Note that caller must hold a transport reference.
+ */
+static void rq_cq_reap(struct svcxprt_rdma *xprt)
+{
+	int ret;
+	struct ib_wc wc;
+	struct svc_rdma_op_ctxt *ctxt = NULL;
+
+	if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags))
+		return;
+
+	ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP);
+	atomic_inc(&rdma_stat_rq_poll);
+
+	while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) {
+		ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id;
+		ctxt->wc_status = wc.status;
+		ctxt->byte_len = wc.byte_len;
+		svc_rdma_unmap_dma(ctxt);
+		if (wc.status != IB_WC_SUCCESS) {
+			/* Close the transport */
+			dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt);
+			set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
+			svc_rdma_put_context(ctxt, 1);
+			svc_xprt_put(&xprt->sc_xprt);
+			continue;
+		}
+		spin_lock_bh(&xprt->sc_rq_dto_lock);
+		list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q);
+		spin_unlock_bh(&xprt->sc_rq_dto_lock);
+		svc_xprt_put(&xprt->sc_xprt);
+	}
+
+	if (ctxt)
+		atomic_inc(&rdma_stat_rq_prod);
+
+	set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
+	/*
+	 * If data arrived before established event,
+	 * don't enqueue. This defers RPC I/O until the
+	 * RDMA connection is complete.
+	 */
+	if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags))
+		svc_xprt_enqueue(&xprt->sc_xprt);
+}
+
+/*
+ * Process a completion context
+ */
+static void process_context(struct svcxprt_rdma *xprt,
+			    struct svc_rdma_op_ctxt *ctxt)
+{
+	svc_rdma_unmap_dma(ctxt);
+
+	switch (ctxt->wr_op) {
+	case IB_WR_SEND:
+		if (ctxt->frmr)
+			pr_err("svcrdma: SEND: ctxt->frmr != NULL\n");
+		svc_rdma_put_context(ctxt, 1);
+		break;
+
+	case IB_WR_RDMA_WRITE:
+		if (ctxt->frmr)
+			pr_err("svcrdma: WRITE: ctxt->frmr != NULL\n");
+		svc_rdma_put_context(ctxt, 0);
+		break;
+
+	case IB_WR_RDMA_READ:
+	case IB_WR_RDMA_READ_WITH_INV:
+		svc_rdma_put_frmr(xprt, ctxt->frmr);
+		if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) {
+			struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr;
+			if (read_hdr) {
+				spin_lock_bh(&xprt->sc_rq_dto_lock);
+				set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
+				list_add_tail(&read_hdr->dto_q,
+					      &xprt->sc_read_complete_q);
+				spin_unlock_bh(&xprt->sc_rq_dto_lock);
+			} else {
+				pr_err("svcrdma: ctxt->read_hdr == NULL\n");
+			}
+			svc_xprt_enqueue(&xprt->sc_xprt);
+		}
+		svc_rdma_put_context(ctxt, 0);
+		break;
+
+	default:
+		printk(KERN_ERR "svcrdma: unexpected completion type, "
+		       "opcode=%d\n",
+		       ctxt->wr_op);
+		break;
+	}
+}
+
+/*
+ * Send Queue Completion Handler - potentially called on interrupt context.
+ *
+ * Note that caller must hold a transport reference.
+ */
+static void sq_cq_reap(struct svcxprt_rdma *xprt)
+{
+	struct svc_rdma_op_ctxt *ctxt = NULL;
+	struct ib_wc wc_a[6];
+	struct ib_wc *wc;
+	struct ib_cq *cq = xprt->sc_sq_cq;
+	int ret;
+
+	memset(wc_a, 0, sizeof(wc_a));
+
+	if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags))
+		return;
+
+	ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP);
+	atomic_inc(&rdma_stat_sq_poll);
+	while ((ret = ib_poll_cq(cq, ARRAY_SIZE(wc_a), wc_a)) > 0) {
+		int i;
+
+		for (i = 0; i < ret; i++) {
+			wc = &wc_a[i];
+			if (wc->status != IB_WC_SUCCESS) {
+				dprintk("svcrdma: sq wc err status %d\n",
+					wc->status);
+
+				/* Close the transport */
+				set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
+			}
+
+			/* Decrement used SQ WR count */
+			atomic_dec(&xprt->sc_sq_count);
+			wake_up(&xprt->sc_send_wait);
+
+			ctxt = (struct svc_rdma_op_ctxt *)
+				(unsigned long)wc->wr_id;
+			if (ctxt)
+				process_context(xprt, ctxt);
+
+			svc_xprt_put(&xprt->sc_xprt);
+		}
+	}
+
+	if (ctxt)
+		atomic_inc(&rdma_stat_sq_prod);
+}
+
+static void sq_comp_handler(struct ib_cq *cq, void *cq_context)
+{
+	struct svcxprt_rdma *xprt = cq_context;
+	unsigned long flags;
+
+	/* Guard against unconditional flush call for destroyed QP */
+	if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0)
+		return;
+
+	/*
+	 * Set the bit regardless of whether or not it's on the list
+	 * because it may be on the list already due to an RQ
+	 * completion.
+	 */
+	set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags);
+
+	/*
+	 * If this transport is not already on the DTO transport queue,
+	 * add it
+	 */
+	spin_lock_irqsave(&dto_lock, flags);
+	if (list_empty(&xprt->sc_dto_q)) {
+		svc_xprt_get(&xprt->sc_xprt);
+		list_add_tail(&xprt->sc_dto_q, &dto_xprt_q);
+	}
+	spin_unlock_irqrestore(&dto_lock, flags);
+
+	/* Tasklet does all the work to avoid irqsave locks. */
+	tasklet_schedule(&dto_tasklet);
+}
+
+static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
+					     int listener)
+{
+	struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL);
+
+	if (!cma_xprt)
+		return NULL;
+	svc_xprt_init(&init_net, &svc_rdma_class, &cma_xprt->sc_xprt, serv);
+	INIT_LIST_HEAD(&cma_xprt->sc_accept_q);
+	INIT_LIST_HEAD(&cma_xprt->sc_dto_q);
+	INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q);
+	INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
+	INIT_LIST_HEAD(&cma_xprt->sc_frmr_q);
+	init_waitqueue_head(&cma_xprt->sc_send_wait);
+
+	spin_lock_init(&cma_xprt->sc_lock);
+	spin_lock_init(&cma_xprt->sc_rq_dto_lock);
+	spin_lock_init(&cma_xprt->sc_frmr_q_lock);
+
+	cma_xprt->sc_ord = svcrdma_ord;
+
+	cma_xprt->sc_max_req_size = svcrdma_max_req_size;
+	cma_xprt->sc_max_requests = svcrdma_max_requests;
+	cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT;
+	atomic_set(&cma_xprt->sc_sq_count, 0);
+	atomic_set(&cma_xprt->sc_ctxt_used, 0);
+
+	if (listener)
+		set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);
+
+	return cma_xprt;
+}
+
+struct page *svc_rdma_get_page(void)
+{
+	struct page *page;
+
+	while ((page = alloc_page(GFP_KERNEL)) == NULL) {
+		/* If we can't get memory, wait a bit and try again */
+		printk(KERN_INFO "svcrdma: out of memory...retrying in 1s\n");
+		schedule_timeout_uninterruptible(msecs_to_jiffies(1000));
+	}
+	return page;
+}
+
+int svc_rdma_post_recv(struct svcxprt_rdma *xprt)
+{
+	struct ib_recv_wr recv_wr, *bad_recv_wr;
+	struct svc_rdma_op_ctxt *ctxt;
+	struct page *page;
+	dma_addr_t pa;
+	int sge_no;
+	int buflen;
+	int ret;
+
+	ctxt = svc_rdma_get_context(xprt);
+	buflen = 0;
+	ctxt->direction = DMA_FROM_DEVICE;
+	for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) {
+		if (sge_no >= xprt->sc_max_sge) {
+			pr_err("svcrdma: Too many sges (%d)\n", sge_no);
+			goto err_put_ctxt;
+		}
+		page = svc_rdma_get_page();
+		ctxt->pages[sge_no] = page;
+		pa = ib_dma_map_page(xprt->sc_cm_id->device,
+				     page, 0, PAGE_SIZE,
+				     DMA_FROM_DEVICE);
+		if (ib_dma_mapping_error(xprt->sc_cm_id->device, pa))
+			goto err_put_ctxt;
+		atomic_inc(&xprt->sc_dma_used);
+		ctxt->sge[sge_no].addr = pa;
+		ctxt->sge[sge_no].length = PAGE_SIZE;
+		ctxt->sge[sge_no].lkey = xprt->sc_dma_lkey;
+		ctxt->count = sge_no + 1;
+		buflen += PAGE_SIZE;
+	}
+	recv_wr.next = NULL;
+	recv_wr.sg_list = &ctxt->sge[0];
+	recv_wr.num_sge = ctxt->count;
+	recv_wr.wr_id = (u64)(unsigned long)ctxt;
+
+	svc_xprt_get(&xprt->sc_xprt);
+	ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr);
+	if (ret) {
+		svc_rdma_unmap_dma(ctxt);
+		svc_rdma_put_context(ctxt, 1);
+		svc_xprt_put(&xprt->sc_xprt);
+	}
+	return ret;
+
+ err_put_ctxt:
+	svc_rdma_unmap_dma(ctxt);
+	svc_rdma_put_context(ctxt, 1);
+	return -ENOMEM;
+}
+
+/*
+ * This function handles the CONNECT_REQUEST event on a listening
+ * endpoint. It is passed the cma_id for the _new_ connection. The context in
+ * this cma_id is inherited from the listening cma_id and is the svc_xprt
+ * structure for the listening endpoint.
+ *
+ * This function creates a new xprt for the new connection and enqueues it on
+ * the accept queue for the listent xprt. When the listen thread is kicked, it
+ * will call the recvfrom method on the listen xprt which will accept the new
+ * connection.
+ */
+static void handle_connect_req(struct rdma_cm_id *new_cma_id, size_t client_ird)
+{
+	struct svcxprt_rdma *listen_xprt = new_cma_id->context;
+	struct svcxprt_rdma *newxprt;
+	struct sockaddr *sa;
+
+	/* Create a new transport */
+	newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0);
+	if (!newxprt) {
+		dprintk("svcrdma: failed to create new transport\n");
+		return;
+	}
+	newxprt->sc_cm_id = new_cma_id;
+	new_cma_id->context = newxprt;
+	dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n",
+		newxprt, newxprt->sc_cm_id, listen_xprt);
+
+	/* Save client advertised inbound read limit for use later in accept. */
+	newxprt->sc_ord = client_ird;
+
+	/* Set the local and remote addresses in the transport */
+	sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr;
+	svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa));
+	sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr;
+	svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa));
+
+	/*
+	 * Enqueue the new transport on the accept queue of the listening
+	 * transport
+	 */
+	spin_lock_bh(&listen_xprt->sc_lock);
+	list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q);
+	spin_unlock_bh(&listen_xprt->sc_lock);
+
+	set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags);
+	svc_xprt_enqueue(&listen_xprt->sc_xprt);
+}
+
+/*
+ * Handles events generated on the listening endpoint. These events will be
+ * either be incoming connect requests or adapter removal  events.
+ */
+static int rdma_listen_handler(struct rdma_cm_id *cma_id,
+			       struct rdma_cm_event *event)
+{
+	struct svcxprt_rdma *xprt = cma_id->context;
+	int ret = 0;
+
+	switch (event->event) {
+	case RDMA_CM_EVENT_CONNECT_REQUEST:
+		dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, "
+			"event=%d\n", cma_id, cma_id->context, event->event);
+		handle_connect_req(cma_id,
+				   event->param.conn.initiator_depth);
+		break;
+
+	case RDMA_CM_EVENT_ESTABLISHED:
+		/* Accept complete */
+		dprintk("svcrdma: Connection completed on LISTEN xprt=%p, "
+			"cm_id=%p\n", xprt, cma_id);
+		break;
+
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+		dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n",
+			xprt, cma_id);
+		if (xprt)
+			set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
+		break;
+
+	default:
+		dprintk("svcrdma: Unexpected event on listening endpoint %p, "
+			"event=%d\n", cma_id, event->event);
+		break;
+	}
+
+	return ret;
+}
+
+static int rdma_cma_handler(struct rdma_cm_id *cma_id,
+			    struct rdma_cm_event *event)
+{
+	struct svc_xprt *xprt = cma_id->context;
+	struct svcxprt_rdma *rdma =
+		container_of(xprt, struct svcxprt_rdma, sc_xprt);
+	switch (event->event) {
+	case RDMA_CM_EVENT_ESTABLISHED:
+		/* Accept complete */
+		svc_xprt_get(xprt);
+		dprintk("svcrdma: Connection completed on DTO xprt=%p, "
+			"cm_id=%p\n", xprt, cma_id);
+		clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags);
+		svc_xprt_enqueue(xprt);
+		break;
+	case RDMA_CM_EVENT_DISCONNECTED:
+		dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n",
+			xprt, cma_id);
+		if (xprt) {
+			set_bit(XPT_CLOSE, &xprt->xpt_flags);
+			svc_xprt_enqueue(xprt);
+			svc_xprt_put(xprt);
+		}
+		break;
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+		dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, "
+			"event=%d\n", cma_id, xprt, event->event);
+		if (xprt) {
+			set_bit(XPT_CLOSE, &xprt->xpt_flags);
+			svc_xprt_enqueue(xprt);
+		}
+		break;
+	default:
+		dprintk("svcrdma: Unexpected event on DTO endpoint %p, "
+			"event=%d\n", cma_id, event->event);
+		break;
+	}
+	return 0;
+}
+
+/*
+ * Create a listening RDMA service endpoint.
+ */
+static struct svc_xprt *svc_rdma_create(struct svc_serv *serv,
+					struct net *net,
+					struct sockaddr *sa, int salen,
+					int flags)
+{
+	struct rdma_cm_id *listen_id;
+	struct svcxprt_rdma *cma_xprt;
+	int ret;
+
+	dprintk("svcrdma: Creating RDMA socket\n");
+	if (sa->sa_family != AF_INET) {
+		dprintk("svcrdma: Address family %d is not supported.\n", sa->sa_family);
+		return ERR_PTR(-EAFNOSUPPORT);
+	}
+	cma_xprt = rdma_create_xprt(serv, 1);
+	if (!cma_xprt)
+		return ERR_PTR(-ENOMEM);
+
+	listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP,
+				   IB_QPT_RC);
+	if (IS_ERR(listen_id)) {
+		ret = PTR_ERR(listen_id);
+		dprintk("svcrdma: rdma_create_id failed = %d\n", ret);
+		goto err0;
+	}
+
+	ret = rdma_bind_addr(listen_id, sa);
+	if (ret) {
+		dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret);
+		goto err1;
+	}
+	cma_xprt->sc_cm_id = listen_id;
+
+	ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG);
+	if (ret) {
+		dprintk("svcrdma: rdma_listen failed = %d\n", ret);
+		goto err1;
+	}
+
+	/*
+	 * We need to use the address from the cm_id in case the
+	 * caller specified 0 for the port number.
+	 */
+	sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr;
+	svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen);
+
+	return &cma_xprt->sc_xprt;
+
+ err1:
+	rdma_destroy_id(listen_id);
+ err0:
+	kfree(cma_xprt);
+	return ERR_PTR(ret);
+}
+
+static struct svc_rdma_fastreg_mr *rdma_alloc_frmr(struct svcxprt_rdma *xprt)
+{
+	struct ib_mr *mr;
+	struct ib_fast_reg_page_list *pl;
+	struct svc_rdma_fastreg_mr *frmr;
+
+	frmr = kmalloc(sizeof(*frmr), GFP_KERNEL);
+	if (!frmr)
+		goto err;
+
+	mr = ib_alloc_fast_reg_mr(xprt->sc_pd, RPCSVC_MAXPAGES);
+	if (IS_ERR(mr))
+		goto err_free_frmr;
+
+	pl = ib_alloc_fast_reg_page_list(xprt->sc_cm_id->device,
+					 RPCSVC_MAXPAGES);
+	if (IS_ERR(pl))
+		goto err_free_mr;
+
+	frmr->mr = mr;
+	frmr->page_list = pl;
+	INIT_LIST_HEAD(&frmr->frmr_list);
+	return frmr;
+
+ err_free_mr:
+	ib_dereg_mr(mr);
+ err_free_frmr:
+	kfree(frmr);
+ err:
+	return ERR_PTR(-ENOMEM);
+}
+
+static void rdma_dealloc_frmr_q(struct svcxprt_rdma *xprt)
+{
+	struct svc_rdma_fastreg_mr *frmr;
+
+	while (!list_empty(&xprt->sc_frmr_q)) {
+		frmr = list_entry(xprt->sc_frmr_q.next,
+				  struct svc_rdma_fastreg_mr, frmr_list);
+		list_del_init(&frmr->frmr_list);
+		ib_dereg_mr(frmr->mr);
+		ib_free_fast_reg_page_list(frmr->page_list);
+		kfree(frmr);
+	}
+}
+
+struct svc_rdma_fastreg_mr *svc_rdma_get_frmr(struct svcxprt_rdma *rdma)
+{
+	struct svc_rdma_fastreg_mr *frmr = NULL;
+
+	spin_lock_bh(&rdma->sc_frmr_q_lock);
+	if (!list_empty(&rdma->sc_frmr_q)) {
+		frmr = list_entry(rdma->sc_frmr_q.next,
+				  struct svc_rdma_fastreg_mr, frmr_list);
+		list_del_init(&frmr->frmr_list);
+		frmr->map_len = 0;
+		frmr->page_list_len = 0;
+	}
+	spin_unlock_bh(&rdma->sc_frmr_q_lock);
+	if (frmr)
+		return frmr;
+
+	return rdma_alloc_frmr(rdma);
+}
+
+static void frmr_unmap_dma(struct svcxprt_rdma *xprt,
+			   struct svc_rdma_fastreg_mr *frmr)
+{
+	int page_no;
+	for (page_no = 0; page_no < frmr->page_list_len; page_no++) {
+		dma_addr_t addr = frmr->page_list->page_list[page_no];
+		if (ib_dma_mapping_error(frmr->mr->device, addr))
+			continue;
+		atomic_dec(&xprt->sc_dma_used);
+		ib_dma_unmap_page(frmr->mr->device, addr, PAGE_SIZE,
+				  frmr->direction);
+	}
+}
+
+void svc_rdma_put_frmr(struct svcxprt_rdma *rdma,
+		       struct svc_rdma_fastreg_mr *frmr)
+{
+	if (frmr) {
+		frmr_unmap_dma(rdma, frmr);
+		spin_lock_bh(&rdma->sc_frmr_q_lock);
+		WARN_ON_ONCE(!list_empty(&frmr->frmr_list));
+		list_add(&frmr->frmr_list, &rdma->sc_frmr_q);
+		spin_unlock_bh(&rdma->sc_frmr_q_lock);
+	}
+}
+
+/*
+ * This is the xpo_recvfrom function for listening endpoints. Its
+ * purpose is to accept incoming connections. The CMA callback handler
+ * has already created a new transport and attached it to the new CMA
+ * ID.
+ *
+ * There is a queue of pending connections hung on the listening
+ * transport. This queue contains the new svc_xprt structure. This
+ * function takes svc_xprt structures off the accept_q and completes
+ * the connection.
+ */
+static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
+{
+	struct svcxprt_rdma *listen_rdma;
+	struct svcxprt_rdma *newxprt = NULL;
+	struct rdma_conn_param conn_param;
+	struct ib_qp_init_attr qp_attr;
+	struct ib_device_attr devattr;
+	int uninitialized_var(dma_mr_acc);
+	int need_dma_mr;
+	int ret;
+	int i;
+
+	listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt);
+	clear_bit(XPT_CONN, &xprt->xpt_flags);
+	/* Get the next entry off the accept list */
+	spin_lock_bh(&listen_rdma->sc_lock);
+	if (!list_empty(&listen_rdma->sc_accept_q)) {
+		newxprt = list_entry(listen_rdma->sc_accept_q.next,
+				     struct svcxprt_rdma, sc_accept_q);
+		list_del_init(&newxprt->sc_accept_q);
+	}
+	if (!list_empty(&listen_rdma->sc_accept_q))
+		set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags);
+	spin_unlock_bh(&listen_rdma->sc_lock);
+	if (!newxprt)
+		return NULL;
+
+	dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n",
+		newxprt, newxprt->sc_cm_id);
+
+	ret = ib_query_device(newxprt->sc_cm_id->device, &devattr);
+	if (ret) {
+		dprintk("svcrdma: could not query device attributes on "
+			"device %p, rc=%d\n", newxprt->sc_cm_id->device, ret);
+		goto errout;
+	}
+
+	/* Qualify the transport resource defaults with the
+	 * capabilities of this particular device */
+	newxprt->sc_max_sge = min((size_t)devattr.max_sge,
+				  (size_t)RPCSVC_MAXPAGES);
+	newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr,
+				   (size_t)svcrdma_max_requests);
+	newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests;
+
+	/*
+	 * Limit ORD based on client limit, local device limit, and
+	 * configured svcrdma limit.
+	 */
+	newxprt->sc_ord = min_t(size_t, devattr.max_qp_rd_atom, newxprt->sc_ord);
+	newxprt->sc_ord = min_t(size_t,	svcrdma_ord, newxprt->sc_ord);
+
+	newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device);
+	if (IS_ERR(newxprt->sc_pd)) {
+		dprintk("svcrdma: error creating PD for connect request\n");
+		goto errout;
+	}
+	newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device,
+					 sq_comp_handler,
+					 cq_event_handler,
+					 newxprt,
+					 newxprt->sc_sq_depth,
+					 0);
+	if (IS_ERR(newxprt->sc_sq_cq)) {
+		dprintk("svcrdma: error creating SQ CQ for connect request\n");
+		goto errout;
+	}
+	newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device,
+					 rq_comp_handler,
+					 cq_event_handler,
+					 newxprt,
+					 newxprt->sc_max_requests,
+					 0);
+	if (IS_ERR(newxprt->sc_rq_cq)) {
+		dprintk("svcrdma: error creating RQ CQ for connect request\n");
+		goto errout;
+	}
+
+	memset(&qp_attr, 0, sizeof qp_attr);
+	qp_attr.event_handler = qp_event_handler;
+	qp_attr.qp_context = &newxprt->sc_xprt;
+	qp_attr.cap.max_send_wr = newxprt->sc_sq_depth;
+	qp_attr.cap.max_recv_wr = newxprt->sc_max_requests;
+	qp_attr.cap.max_send_sge = newxprt->sc_max_sge;
+	qp_attr.cap.max_recv_sge = newxprt->sc_max_sge;
+	qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
+	qp_attr.qp_type = IB_QPT_RC;
+	qp_attr.send_cq = newxprt->sc_sq_cq;
+	qp_attr.recv_cq = newxprt->sc_rq_cq;
+	dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n"
+		"    cm_id->device=%p, sc_pd->device=%p\n"
+		"    cap.max_send_wr = %d\n"
+		"    cap.max_recv_wr = %d\n"
+		"    cap.max_send_sge = %d\n"
+		"    cap.max_recv_sge = %d\n",
+		newxprt->sc_cm_id, newxprt->sc_pd,
+		newxprt->sc_cm_id->device, newxprt->sc_pd->device,
+		qp_attr.cap.max_send_wr,
+		qp_attr.cap.max_recv_wr,
+		qp_attr.cap.max_send_sge,
+		qp_attr.cap.max_recv_sge);
+
+	ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr);
+	if (ret) {
+		dprintk("svcrdma: failed to create QP, ret=%d\n", ret);
+		goto errout;
+	}
+	newxprt->sc_qp = newxprt->sc_cm_id->qp;
+
+	/*
+	 * Use the most secure set of MR resources based on the
+	 * transport type and available memory management features in
+	 * the device. Here's the table implemented below:
+	 *
+	 *		Fast	Global	DMA	Remote WR
+	 *		Reg	LKEY	MR	Access
+	 *		Sup'd	Sup'd	Needed	Needed
+	 *
+	 * IWARP	N	N	Y	Y
+	 *		N	Y	Y	Y
+	 *		Y	N	Y	N
+	 *		Y	Y	N	-
+	 *
+	 * IB		N	N	Y	N
+	 *		N	Y	N	-
+	 *		Y	N	Y	N
+	 *		Y	Y	N	-
+	 *
+	 * NB:	iWARP requires remote write access for the data sink
+	 *	of an RDMA_READ. IB does not.
+	 */
+	newxprt->sc_reader = rdma_read_chunk_lcl;
+	if (devattr.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) {
+		newxprt->sc_frmr_pg_list_len =
+			devattr.max_fast_reg_page_list_len;
+		newxprt->sc_dev_caps |= SVCRDMA_DEVCAP_FAST_REG;
+		newxprt->sc_reader = rdma_read_chunk_frmr;
+	}
+
+	/*
+	 * Determine if a DMA MR is required and if so, what privs are required
+	 */
+	switch (rdma_node_get_transport(newxprt->sc_cm_id->device->node_type)) {
+	case RDMA_TRANSPORT_IWARP:
+		newxprt->sc_dev_caps |= SVCRDMA_DEVCAP_READ_W_INV;
+		if (!(newxprt->sc_dev_caps & SVCRDMA_DEVCAP_FAST_REG)) {
+			need_dma_mr = 1;
+			dma_mr_acc =
+				(IB_ACCESS_LOCAL_WRITE |
+				 IB_ACCESS_REMOTE_WRITE);
+		} else if (!(devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)) {
+			need_dma_mr = 1;
+			dma_mr_acc = IB_ACCESS_LOCAL_WRITE;
+		} else
+			need_dma_mr = 0;
+		break;
+	case RDMA_TRANSPORT_IB:
+		if (!(newxprt->sc_dev_caps & SVCRDMA_DEVCAP_FAST_REG)) {
+			need_dma_mr = 1;
+			dma_mr_acc = IB_ACCESS_LOCAL_WRITE;
+		} else if (!(devattr.device_cap_flags &
+			     IB_DEVICE_LOCAL_DMA_LKEY)) {
+			need_dma_mr = 1;
+			dma_mr_acc = IB_ACCESS_LOCAL_WRITE;
+		} else
+			need_dma_mr = 0;
+		break;
+	default:
+		goto errout;
+	}
+
+	/* Create the DMA MR if needed, otherwise, use the DMA LKEY */
+	if (need_dma_mr) {
+		/* Register all of physical memory */
+		newxprt->sc_phys_mr =
+			ib_get_dma_mr(newxprt->sc_pd, dma_mr_acc);
+		if (IS_ERR(newxprt->sc_phys_mr)) {
+			dprintk("svcrdma: Failed to create DMA MR ret=%d\n",
+				ret);
+			goto errout;
+		}
+		newxprt->sc_dma_lkey = newxprt->sc_phys_mr->lkey;
+	} else
+		newxprt->sc_dma_lkey =
+			newxprt->sc_cm_id->device->local_dma_lkey;
+
+	/* Post receive buffers */
+	for (i = 0; i < newxprt->sc_max_requests; i++) {
+		ret = svc_rdma_post_recv(newxprt);
+		if (ret) {
+			dprintk("svcrdma: failure posting receive buffers\n");
+			goto errout;
+		}
+	}
+
+	/* Swap out the handler */
+	newxprt->sc_cm_id->event_handler = rdma_cma_handler;
+
+	/*
+	 * Arm the CQs for the SQ and RQ before accepting so we can't
+	 * miss the first message
+	 */
+	ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP);
+	ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP);
+
+	/* Accept Connection */
+	set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags);
+	memset(&conn_param, 0, sizeof conn_param);
+	conn_param.responder_resources = 0;
+	conn_param.initiator_depth = newxprt->sc_ord;
+	ret = rdma_accept(newxprt->sc_cm_id, &conn_param);
+	if (ret) {
+		dprintk("svcrdma: failed to accept new connection, ret=%d\n",
+		       ret);
+		goto errout;
+	}
+
+	dprintk("svcrdma: new connection %p accepted with the following "
+		"attributes:\n"
+		"    local_ip        : %pI4\n"
+		"    local_port	     : %d\n"
+		"    remote_ip       : %pI4\n"
+		"    remote_port     : %d\n"
+		"    max_sge         : %d\n"
+		"    sq_depth        : %d\n"
+		"    max_requests    : %d\n"
+		"    ord             : %d\n",
+		newxprt,
+		&((struct sockaddr_in *)&newxprt->sc_cm_id->
+			 route.addr.src_addr)->sin_addr.s_addr,
+		ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
+		       route.addr.src_addr)->sin_port),
+		&((struct sockaddr_in *)&newxprt->sc_cm_id->
+			 route.addr.dst_addr)->sin_addr.s_addr,
+		ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id->
+		       route.addr.dst_addr)->sin_port),
+		newxprt->sc_max_sge,
+		newxprt->sc_sq_depth,
+		newxprt->sc_max_requests,
+		newxprt->sc_ord);
+
+	return &newxprt->sc_xprt;
+
+ errout:
+	dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret);
+	/* Take a reference in case the DTO handler runs */
+	svc_xprt_get(&newxprt->sc_xprt);
+	if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp))
+		ib_destroy_qp(newxprt->sc_qp);
+	rdma_destroy_id(newxprt->sc_cm_id);
+	/* This call to put will destroy the transport */
+	svc_xprt_put(&newxprt->sc_xprt);
+	return NULL;
+}
+
+static void svc_rdma_release_rqst(struct svc_rqst *rqstp)
+{
+}
+
+/*
+ * When connected, an svc_xprt has at least two references:
+ *
+ * - A reference held by the cm_id between the ESTABLISHED and
+ *   DISCONNECTED events. If the remote peer disconnected first, this
+ *   reference could be gone.
+ *
+ * - A reference held by the svc_recv code that called this function
+ *   as part of close processing.
+ *
+ * At a minimum one references should still be held.
+ */
+static void svc_rdma_detach(struct svc_xprt *xprt)
+{
+	struct svcxprt_rdma *rdma =
+		container_of(xprt, struct svcxprt_rdma, sc_xprt);
+	dprintk("svc: svc_rdma_detach(%p)\n", xprt);
+
+	/* Disconnect and flush posted WQE */
+	rdma_disconnect(rdma->sc_cm_id);
+}
+
+static void __svc_rdma_free(struct work_struct *work)
+{
+	struct svcxprt_rdma *rdma =
+		container_of(work, struct svcxprt_rdma, sc_work);
+	dprintk("svcrdma: svc_rdma_free(%p)\n", rdma);
+
+	/* We should only be called from kref_put */
+	if (atomic_read(&rdma->sc_xprt.xpt_ref.refcount) != 0)
+		pr_err("svcrdma: sc_xprt still in use? (%d)\n",
+		       atomic_read(&rdma->sc_xprt.xpt_ref.refcount));
+
+	/*
+	 * Destroy queued, but not processed read completions. Note
+	 * that this cleanup has to be done before destroying the
+	 * cm_id because the device ptr is needed to unmap the dma in
+	 * svc_rdma_put_context.
+	 */
+	while (!list_empty(&rdma->sc_read_complete_q)) {
+		struct svc_rdma_op_ctxt *ctxt;
+		ctxt = list_entry(rdma->sc_read_complete_q.next,
+				  struct svc_rdma_op_ctxt,
+				  dto_q);
+		list_del_init(&ctxt->dto_q);
+		svc_rdma_put_context(ctxt, 1);
+	}
+
+	/* Destroy queued, but not processed recv completions */
+	while (!list_empty(&rdma->sc_rq_dto_q)) {
+		struct svc_rdma_op_ctxt *ctxt;
+		ctxt = list_entry(rdma->sc_rq_dto_q.next,
+				  struct svc_rdma_op_ctxt,
+				  dto_q);
+		list_del_init(&ctxt->dto_q);
+		svc_rdma_put_context(ctxt, 1);
+	}
+
+	/* Warn if we leaked a resource or under-referenced */
+	if (atomic_read(&rdma->sc_ctxt_used) != 0)
+		pr_err("svcrdma: ctxt still in use? (%d)\n",
+		       atomic_read(&rdma->sc_ctxt_used));
+	if (atomic_read(&rdma->sc_dma_used) != 0)
+		pr_err("svcrdma: dma still in use? (%d)\n",
+		       atomic_read(&rdma->sc_dma_used));
+
+	/* De-allocate fastreg mr */
+	rdma_dealloc_frmr_q(rdma);
+
+	/* Destroy the QP if present (not a listener) */
+	if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))
+		ib_destroy_qp(rdma->sc_qp);
+
+	if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq))
+		ib_destroy_cq(rdma->sc_sq_cq);
+
+	if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq))
+		ib_destroy_cq(rdma->sc_rq_cq);
+
+	if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr))
+		ib_dereg_mr(rdma->sc_phys_mr);
+
+	if (rdma->sc_pd && !IS_ERR(rdma->sc_pd))
+		ib_dealloc_pd(rdma->sc_pd);
+
+	/* Destroy the CM ID */
+	rdma_destroy_id(rdma->sc_cm_id);
+
+	kfree(rdma);
+}
+
+static void svc_rdma_free(struct svc_xprt *xprt)
+{
+	struct svcxprt_rdma *rdma =
+		container_of(xprt, struct svcxprt_rdma, sc_xprt);
+	INIT_WORK(&rdma->sc_work, __svc_rdma_free);
+	queue_work(svc_rdma_wq, &rdma->sc_work);
+}
+
+static int svc_rdma_has_wspace(struct svc_xprt *xprt)
+{
+	struct svcxprt_rdma *rdma =
+		container_of(xprt, struct svcxprt_rdma, sc_xprt);
+
+	/*
+	 * If there are already waiters on the SQ,
+	 * return false.
+	 */
+	if (waitqueue_active(&rdma->sc_send_wait))
+		return 0;
+
+	/* Otherwise return true. */
+	return 1;
+}
+
+static int svc_rdma_secure_port(struct svc_rqst *rqstp)
+{
+	return 1;
+}
+
+/*
+ * Attempt to register the kvec representing the RPC memory with the
+ * device.
+ *
+ * Returns:
+ *  NULL : The device does not support fastreg or there were no more
+ *         fastreg mr.
+ *  frmr : The kvec register request was successfully posted.
+ *    <0 : An error was encountered attempting to register the kvec.
+ */
+int svc_rdma_fastreg(struct svcxprt_rdma *xprt,
+		     struct svc_rdma_fastreg_mr *frmr)
+{
+	struct ib_send_wr fastreg_wr;
+	u8 key;
+
+	/* Bump the key */
+	key = (u8)(frmr->mr->lkey & 0x000000FF);
+	ib_update_fast_reg_key(frmr->mr, ++key);
+
+	/* Prepare FASTREG WR */
+	memset(&fastreg_wr, 0, sizeof fastreg_wr);
+	fastreg_wr.opcode = IB_WR_FAST_REG_MR;
+	fastreg_wr.send_flags = IB_SEND_SIGNALED;
+	fastreg_wr.wr.fast_reg.iova_start = (unsigned long)frmr->kva;
+	fastreg_wr.wr.fast_reg.page_list = frmr->page_list;
+	fastreg_wr.wr.fast_reg.page_list_len = frmr->page_list_len;
+	fastreg_wr.wr.fast_reg.page_shift = PAGE_SHIFT;
+	fastreg_wr.wr.fast_reg.length = frmr->map_len;
+	fastreg_wr.wr.fast_reg.access_flags = frmr->access_flags;
+	fastreg_wr.wr.fast_reg.rkey = frmr->mr->lkey;
+	return svc_rdma_send(xprt, &fastreg_wr);
+}
+
+int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr)
+{
+	struct ib_send_wr *bad_wr, *n_wr;
+	int wr_count;
+	int i;
+	int ret;
+
+	if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
+		return -ENOTCONN;
+
+	wr_count = 1;
+	for (n_wr = wr->next; n_wr; n_wr = n_wr->next)
+		wr_count++;
+
+	/* If the SQ is full, wait until an SQ entry is available */
+	while (1) {
+		spin_lock_bh(&xprt->sc_lock);
+		if (xprt->sc_sq_depth < atomic_read(&xprt->sc_sq_count) + wr_count) {
+			spin_unlock_bh(&xprt->sc_lock);
+			atomic_inc(&rdma_stat_sq_starve);
+
+			/* See if we can opportunistically reap SQ WR to make room */
+			sq_cq_reap(xprt);
+
+			/* Wait until SQ WR available if SQ still full */
+			wait_event(xprt->sc_send_wait,
+				   atomic_read(&xprt->sc_sq_count) <
+				   xprt->sc_sq_depth);
+			if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags))
+				return -ENOTCONN;
+			continue;
+		}
+		/* Take a transport ref for each WR posted */
+		for (i = 0; i < wr_count; i++)
+			svc_xprt_get(&xprt->sc_xprt);
+
+		/* Bump used SQ WR count and post */
+		atomic_add(wr_count, &xprt->sc_sq_count);
+		ret = ib_post_send(xprt->sc_qp, wr, &bad_wr);
+		if (ret) {
+			set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
+			atomic_sub(wr_count, &xprt->sc_sq_count);
+			for (i = 0; i < wr_count; i ++)
+				svc_xprt_put(&xprt->sc_xprt);
+			dprintk("svcrdma: failed to post SQ WR rc=%d, "
+			       "sc_sq_count=%d, sc_sq_depth=%d\n",
+			       ret, atomic_read(&xprt->sc_sq_count),
+			       xprt->sc_sq_depth);
+		}
+		spin_unlock_bh(&xprt->sc_lock);
+		if (ret)
+			wake_up(&xprt->sc_send_wait);
+		break;
+	}
+	return ret;
+}
+
+void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
+			 enum rpcrdma_errcode err)
+{
+	struct ib_send_wr err_wr;
+	struct page *p;
+	struct svc_rdma_op_ctxt *ctxt;
+	u32 *va;
+	int length;
+	int ret;
+
+	p = svc_rdma_get_page();
+	va = page_address(p);
+
+	/* XDR encode error */
+	length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
+
+	ctxt = svc_rdma_get_context(xprt);
+	ctxt->direction = DMA_FROM_DEVICE;
+	ctxt->count = 1;
+	ctxt->pages[0] = p;
+
+	/* Prepare SGE for local address */
+	ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device,
+					    p, 0, length, DMA_FROM_DEVICE);
+	if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) {
+		put_page(p);
+		svc_rdma_put_context(ctxt, 1);
+		return;
+	}
+	atomic_inc(&xprt->sc_dma_used);
+	ctxt->sge[0].lkey = xprt->sc_dma_lkey;
+	ctxt->sge[0].length = length;
+
+	/* Prepare SEND WR */
+	memset(&err_wr, 0, sizeof err_wr);
+	ctxt->wr_op = IB_WR_SEND;
+	err_wr.wr_id = (unsigned long)ctxt;
+	err_wr.sg_list = ctxt->sge;
+	err_wr.num_sge = 1;
+	err_wr.opcode = IB_WR_SEND;
+	err_wr.send_flags = IB_SEND_SIGNALED;
+
+	/* Post It */
+	ret = svc_rdma_send(xprt, &err_wr);
+	if (ret) {
+		dprintk("svcrdma: Error %d posting send for protocol error\n",
+			ret);
+		svc_rdma_unmap_dma(ctxt);
+		svc_rdma_put_context(ctxt, 1);
+	}
+}