Merge tag 'nfs-rdma-4.10-1' of git://git.linux-nfs.org/projects/anna/nfs-rdma

NFS: NFSoRDMA Client Side Changes

New Features:
- Support for SG_GAP devices

Bugfixes and cleanups:
- Cap size of callback buffer resources
- Improve send queue and RPC metric accounting
- Fix coverity warning
- Avoid calls to ro_unmap_safe()
- Refactor FRMR invalidation
- Error message improvements

7 files changed, 128 insertions, 118 deletions

diff --git a/net/sunrpc/stats.c b/net/sunrpc/stats.c
index 2ecb994..caeb01a 100644
--- a/net/sunrpc/stats.c
+++ b/net/sunrpc/stats.c
@@ -157,15 +157,17 @@ void rpc_count_iostats_metrics(const struct rpc_task *task,
 	spin_lock(&op_metrics->om_lock);
 
 	op_metrics->om_ops++;
-	op_metrics->om_ntrans += req->rq_ntrans;
+	/* kernel API: om_ops must never become larger than om_ntrans */
+	op_metrics->om_ntrans += max(req->rq_ntrans, 1);
 	op_metrics->om_timeouts += task->tk_timeouts;
 
 	op_metrics->om_bytes_sent += req->rq_xmit_bytes_sent;
 	op_metrics->om_bytes_recv += req->rq_reply_bytes_recvd;
 
-	delta = ktime_sub(req->rq_xtime, task->tk_start);
-	op_metrics->om_queue = ktime_add(op_metrics->om_queue, delta);
-
+	if (ktime_to_ns(req->rq_xtime)) {
+		delta = ktime_sub(req->rq_xtime, task->tk_start);
+		op_metrics->om_queue = ktime_add(op_metrics->om_queue, delta);
+	}
 	op_metrics->om_rtt = ktime_add(op_metrics->om_rtt, req->rq_rtt);
 
 	delta = ktime_sub(now, task->tk_start);
diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c
index 2c472e1..24fedd4 100644
--- a/net/sunrpc/xprtrdma/backchannel.c
+++ b/net/sunrpc/xprtrdma/backchannel.c
@@ -55,7 +55,8 @@ static int rpcrdma_bc_setup_rqst(struct rpcrdma_xprt *r_xprt,
 	if (IS_ERR(rb))
 		goto out_fail;
 	req->rl_sendbuf = rb;
-	xdr_buf_init(&rqst->rq_snd_buf, rb->rg_base, size);
+	xdr_buf_init(&rqst->rq_snd_buf, rb->rg_base,
+		     min_t(size_t, size, PAGE_SIZE));
 	rpcrdma_set_xprtdata(rqst, req);
 	return 0;
 
@@ -191,6 +192,7 @@ size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *xprt)
 	size_t maxmsg;
 
 	maxmsg = min_t(unsigned int, cdata->inline_rsize, cdata->inline_wsize);
+	maxmsg = min_t(unsigned int, maxmsg, PAGE_SIZE);
 	return maxmsg - RPCRDMA_HDRLEN_MIN;
 }
 
diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c
index 26b26be..47bed53 100644
--- a/net/sunrpc/xprtrdma/frwr_ops.c
+++ b/net/sunrpc/xprtrdma/frwr_ops.c
@@ -101,7 +101,7 @@ frwr_op_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mw *r)
 	struct rpcrdma_frmr *f = &r->frmr;
 	int rc;
 
-	f->fr_mr = ib_alloc_mr(ia->ri_pd, IB_MR_TYPE_MEM_REG, depth);
+	f->fr_mr = ib_alloc_mr(ia->ri_pd, ia->ri_mrtype, depth);
 	if (IS_ERR(f->fr_mr))
 		goto out_mr_err;
 
@@ -157,7 +157,7 @@ __frwr_reset_mr(struct rpcrdma_ia *ia, struct rpcrdma_mw *r)
 		return rc;
 	}
 
-	f->fr_mr = ib_alloc_mr(ia->ri_pd, IB_MR_TYPE_MEM_REG,
+	f->fr_mr = ib_alloc_mr(ia->ri_pd, ia->ri_mrtype,
 			       ia->ri_max_frmr_depth);
 	if (IS_ERR(f->fr_mr)) {
 		pr_warn("rpcrdma: ib_alloc_mr status %ld, frwr %p orphaned\n",
@@ -171,10 +171,6 @@ __frwr_reset_mr(struct rpcrdma_ia *ia, struct rpcrdma_mw *r)
 }
 
 /* Reset of a single FRMR. Generate a fresh rkey by replacing the MR.
- *
- * There's no recovery if this fails. The FRMR is abandoned, but
- * remains in rb_all. It will be cleaned up when the transport is
- * destroyed.
  */
 static void
 frwr_op_recover_mr(struct rpcrdma_mw *mw)
@@ -210,11 +206,16 @@ static int
 frwr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep,
 	     struct rpcrdma_create_data_internal *cdata)
 {
+	struct ib_device_attr *attrs = &ia->ri_device->attrs;
 	int depth, delta;
 
+	ia->ri_mrtype = IB_MR_TYPE_MEM_REG;
+	if (attrs->device_cap_flags & IB_DEVICE_SG_GAPS_REG)
+		ia->ri_mrtype = IB_MR_TYPE_SG_GAPS;
+
 	ia->ri_max_frmr_depth =
 			min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
-			      ia->ri_device->attrs.max_fast_reg_page_list_len);
+			      attrs->max_fast_reg_page_list_len);
 	dprintk("RPC:       %s: device's max FR page list len = %u\n",
 		__func__, ia->ri_max_frmr_depth);
 
@@ -241,8 +242,8 @@ frwr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep,
 	}
 
 	ep->rep_attr.cap.max_send_wr *= depth;
-	if (ep->rep_attr.cap.max_send_wr > ia->ri_device->attrs.max_qp_wr) {
-		cdata->max_requests = ia->ri_device->attrs.max_qp_wr / depth;
+	if (ep->rep_attr.cap.max_send_wr > attrs->max_qp_wr) {
+		cdata->max_requests = attrs->max_qp_wr / depth;
 		if (!cdata->max_requests)
 			return -EINVAL;
 		ep->rep_attr.cap.max_send_wr = cdata->max_requests *
@@ -348,6 +349,7 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 	    int nsegs, bool writing, struct rpcrdma_mw **out)
 {
 	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
+	bool holes_ok = ia->ri_mrtype == IB_MR_TYPE_SG_GAPS;
 	struct rpcrdma_mw *mw;
 	struct rpcrdma_frmr *frmr;
 	struct ib_mr *mr;
@@ -383,8 +385,8 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 
 		++seg;
 		++i;
-
-		/* Check for holes */
+		if (holes_ok)
+			continue;
 		if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
 		    offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
 			break;
@@ -421,7 +423,7 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 			 IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
 			 IB_ACCESS_REMOTE_READ;
 
-	DECR_CQCOUNT(&r_xprt->rx_ep);
+	rpcrdma_set_signaled(&r_xprt->rx_ep, &reg_wr->wr);
 	rc = ib_post_send(ia->ri_id->qp, &reg_wr->wr, &bad_wr);
 	if (rc)
 		goto out_senderr;
@@ -451,26 +453,6 @@ out_senderr:
 	return -ENOTCONN;
 }
 
-static struct ib_send_wr *
-__frwr_prepare_linv_wr(struct rpcrdma_mw *mw)
-{
-	struct rpcrdma_frmr *f = &mw->frmr;
-	struct ib_send_wr *invalidate_wr;
-
-	dprintk("RPC:       %s: invalidating frmr %p\n", __func__, f);
-
-	f->fr_state = FRMR_IS_INVALID;
-	invalidate_wr = &f->fr_invwr;
-
-	memset(invalidate_wr, 0, sizeof(*invalidate_wr));
-	f->fr_cqe.done = frwr_wc_localinv;
-	invalidate_wr->wr_cqe = &f->fr_cqe;
-	invalidate_wr->opcode = IB_WR_LOCAL_INV;
-	invalidate_wr->ex.invalidate_rkey = f->fr_mr->rkey;
-
-	return invalidate_wr;
-}
-
 /* Invalidate all memory regions that were registered for "req".
  *
  * Sleeps until it is safe for the host CPU to access the
@@ -481,12 +463,12 @@ __frwr_prepare_linv_wr(struct rpcrdma_mw *mw)
 static void
 frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
 {
-	struct ib_send_wr *invalidate_wrs, *pos, *prev, *bad_wr;
+	struct ib_send_wr *first, **prev, *last, *bad_wr;
 	struct rpcrdma_rep *rep = req->rl_reply;
 	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
 	struct rpcrdma_mw *mw, *tmp;
 	struct rpcrdma_frmr *f;
-	int rc;
+	int count, rc;
 
 	dprintk("RPC:       %s: req %p\n", __func__, req);
 
@@ -496,22 +478,29 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
 	 * a single ib_post_send() call.
 	 */
 	f = NULL;
-	invalidate_wrs = pos = prev = NULL;
+	count = 0;
+	prev = &first;
 	list_for_each_entry(mw, &req->rl_registered, mw_list) {
+		mw->frmr.fr_state = FRMR_IS_INVALID;
+
 		if ((rep->rr_wc_flags & IB_WC_WITH_INVALIDATE) &&
-		    (mw->mw_handle == rep->rr_inv_rkey)) {
-			mw->frmr.fr_state = FRMR_IS_INVALID;
+		    (mw->mw_handle == rep->rr_inv_rkey))
 			continue;
-		}
-
-		pos = __frwr_prepare_linv_wr(mw);
 
-		if (!invalidate_wrs)
-			invalidate_wrs = pos;
-		else
-			prev->next = pos;
-		prev = pos;
 		f = &mw->frmr;
+		dprintk("RPC:       %s: invalidating frmr %p\n",
+			__func__, f);
+
+		f->fr_cqe.done = frwr_wc_localinv;
+		last = &f->fr_invwr;
+		memset(last, 0, sizeof(*last));
+		last->wr_cqe = &f->fr_cqe;
+		last->opcode = IB_WR_LOCAL_INV;
+		last->ex.invalidate_rkey = mw->mw_handle;
+		count++;
+
+		*prev = last;
+		prev = &last->next;
 	}
 	if (!f)
 		goto unmap;
@@ -520,17 +509,22 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
 	 * last WR in the chain completes, all WRs in the chain
 	 * are complete.
 	 */
-	f->fr_invwr.send_flags = IB_SEND_SIGNALED;
+	last->send_flags = IB_SEND_SIGNALED;
 	f->fr_cqe.done = frwr_wc_localinv_wake;
 	reinit_completion(&f->fr_linv_done);
-	INIT_CQCOUNT(&r_xprt->rx_ep);
+
+	/* Initialize CQ count, since there is always a signaled
+	 * WR being posted here.  The new cqcount depends on how
+	 * many SQEs are about to be consumed.
+	 */
+	rpcrdma_init_cqcount(&r_xprt->rx_ep, count);
 
 	/* Transport disconnect drains the receive CQ before it
 	 * replaces the QP. The RPC reply handler won't call us
 	 * unless ri_id->qp is a valid pointer.
 	 */
 	r_xprt->rx_stats.local_inv_needed++;
-	rc = ib_post_send(ia->ri_id->qp, invalidate_wrs, &bad_wr);
+	rc = ib_post_send(ia->ri_id->qp, first, &bad_wr);
 	if (rc)
 		goto reset_mrs;
 
@@ -541,7 +535,7 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
 	 */
 unmap:
 	list_for_each_entry_safe(mw, tmp, &req->rl_registered, mw_list) {
-		dprintk("RPC:       %s: unmapping frmr %p\n",
+		dprintk("RPC:       %s: DMA unmapping frmr %p\n",
 			__func__, &mw->frmr);
 		list_del_init(&mw->mw_list);
 		ib_dma_unmap_sg(ia->ri_device,
@@ -559,7 +553,7 @@ reset_mrs:
 	 */
 	list_for_each_entry(mw, &req->rl_registered, mw_list) {
 		f = &mw->frmr;
-		if (mw->frmr.fr_mr->rkey == bad_wr->ex.invalidate_rkey) {
+		if (mw->mw_handle == bad_wr->ex.invalidate_rkey) {
 			__frwr_reset_mr(ia, mw);
 			bad_wr = bad_wr->next;
 		}
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index d987c2d..c52e0f2 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -786,7 +786,7 @@ rpcrdma_count_chunks(struct rpcrdma_rep *rep, int wrchunk, __be32 **iptrp)
 		ifdebug(FACILITY) {
 			u64 off;
 			xdr_decode_hyper((__be32 *)&seg->rs_offset, &off);
-			dprintk("RPC:       %s: chunk %d@0x%llx:0x%x\n",
+			dprintk("RPC:       %s: chunk %d@0x%016llx:0x%08x\n",
 				__func__,
 				be32_to_cpu(seg->rs_length),
 				(unsigned long long)off,
@@ -906,28 +906,6 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
 	return fixup_copy_count;
 }
 
-void
-rpcrdma_connect_worker(struct work_struct *work)
-{
-	struct rpcrdma_ep *ep =
-		container_of(work, struct rpcrdma_ep, rep_connect_worker.work);
-	struct rpcrdma_xprt *r_xprt =
-		container_of(ep, struct rpcrdma_xprt, rx_ep);
-	struct rpc_xprt *xprt = &r_xprt->rx_xprt;
-
-	spin_lock_bh(&xprt->transport_lock);
-	if (++xprt->connect_cookie == 0)	/* maintain a reserved value */
-		++xprt->connect_cookie;
-	if (ep->rep_connected > 0) {
-		if (!xprt_test_and_set_connected(xprt))
-			xprt_wake_pending_tasks(xprt, 0);
-	} else {
-		if (xprt_test_and_clear_connected(xprt))
-			xprt_wake_pending_tasks(xprt, -ENOTCONN);
-	}
-	spin_unlock_bh(&xprt->transport_lock);
-}
-
 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 /* By convention, backchannel calls arrive via rdma_msg type
  * messages, and never populate the chunk lists. This makes
@@ -959,18 +937,6 @@ rpcrdma_is_bcall(struct rpcrdma_msg *headerp)
 }
 #endif	/* CONFIG_SUNRPC_BACKCHANNEL */
 
-/*
- * This function is called when an async event is posted to
- * the connection which changes the connection state. All it
- * does at this point is mark the connection up/down, the rpc
- * timers do the rest.
- */
-void
-rpcrdma_conn_func(struct rpcrdma_ep *ep)
-{
-	schedule_delayed_work(&ep->rep_connect_worker, 0);
-}
-
 /* Process received RPC/RDMA messages.
  *
  * Errors must result in the RPC task either being awakened, or
diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c
index ed5e285..534c178 100644
--- a/net/sunrpc/xprtrdma/transport.c
+++ b/net/sunrpc/xprtrdma/transport.c
@@ -219,6 +219,34 @@ xprt_rdma_free_addresses(struct rpc_xprt *xprt)
 		}
 }
 
+void
+rpcrdma_conn_func(struct rpcrdma_ep *ep)
+{
+	schedule_delayed_work(&ep->rep_connect_worker, 0);
+}
+
+void
+rpcrdma_connect_worker(struct work_struct *work)
+{
+	struct rpcrdma_ep *ep =
+		container_of(work, struct rpcrdma_ep, rep_connect_worker.work);
+	struct rpcrdma_xprt *r_xprt =
+		container_of(ep, struct rpcrdma_xprt, rx_ep);
+	struct rpc_xprt *xprt = &r_xprt->rx_xprt;
+
+	spin_lock_bh(&xprt->transport_lock);
+	if (++xprt->connect_cookie == 0)	/* maintain a reserved value */
+		++xprt->connect_cookie;
+	if (ep->rep_connected > 0) {
+		if (!xprt_test_and_set_connected(xprt))
+			xprt_wake_pending_tasks(xprt, 0);
+	} else {
+		if (xprt_test_and_clear_connected(xprt))
+			xprt_wake_pending_tasks(xprt, -ENOTCONN);
+	}
+	spin_unlock_bh(&xprt->transport_lock);
+}
+
 static void
 xprt_rdma_connect_worker(struct work_struct *work)
 {
@@ -621,7 +649,8 @@ xprt_rdma_free(struct rpc_task *task)
 
 	dprintk("RPC:       %s: called on 0x%p\n", __func__, req->rl_reply);
 
-	ia->ri_ops->ro_unmap_safe(r_xprt, req, !RPC_IS_ASYNC(task));
+	if (unlikely(!list_empty(&req->rl_registered)))
+		ia->ri_ops->ro_unmap_safe(r_xprt, req, !RPC_IS_ASYNC(task));
 	rpcrdma_unmap_sges(ia, req);
 	rpcrdma_buffer_put(req);
 }
@@ -657,7 +686,8 @@ xprt_rdma_send_request(struct rpc_task *task)
 	int rc = 0;
 
 	/* On retransmit, remove any previously registered chunks */
-	r_xprt->rx_ia.ri_ops->ro_unmap_safe(r_xprt, req, false);
+	if (unlikely(!list_empty(&req->rl_registered)))
+		r_xprt->rx_ia.ri_ops->ro_unmap_safe(r_xprt, req, false);
 
 	rc = rpcrdma_marshal_req(rqst);
 	if (rc < 0)
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index ec74289..11d0774 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -103,9 +103,9 @@ rpcrdma_qp_async_error_upcall(struct ib_event *event, void *context)
 {
 	struct rpcrdma_ep *ep = context;
 
-	pr_err("RPC:       %s: %s on device %s ep %p\n",
-	       __func__, ib_event_msg(event->event),
-		event->device->name, context);
+	pr_err("rpcrdma: %s on device %s ep %p\n",
+	       ib_event_msg(event->event), event->device->name, context);
+
 	if (ep->rep_connected == 1) {
 		ep->rep_connected = -EIO;
 		rpcrdma_conn_func(ep);
@@ -223,8 +223,8 @@ rpcrdma_update_connect_private(struct rpcrdma_xprt *r_xprt,
 		cdata->inline_rsize = rsize;
 	if (wsize < cdata->inline_wsize)
 		cdata->inline_wsize = wsize;
-	pr_info("rpcrdma: max send %u, max recv %u\n",
-		cdata->inline_wsize, cdata->inline_rsize);
+	dprintk("RPC:       %s: max send %u, max recv %u\n",
+		__func__, cdata->inline_wsize, cdata->inline_rsize);
 	rpcrdma_set_max_header_sizes(r_xprt);
 }
 
@@ -331,6 +331,7 @@ static struct rdma_cm_id *
 rpcrdma_create_id(struct rpcrdma_xprt *xprt,
 			struct rpcrdma_ia *ia, struct sockaddr *addr)
 {
+	unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1;
 	struct rdma_cm_id *id;
 	int rc;
 
@@ -352,8 +353,12 @@ rpcrdma_create_id(struct rpcrdma_xprt *xprt,
 			__func__, rc);
 		goto out;
 	}
-	wait_for_completion_interruptible_timeout(&ia->ri_done,
-				msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1);
+	rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
+	if (rc < 0) {
+		dprintk("RPC:       %s: wait() exited: %i\n",
+			__func__, rc);
+		goto out;
+	}
 
 	/* FIXME:
 	 * Until xprtrdma supports DEVICE_REMOVAL, the provider must
@@ -376,8 +381,12 @@ rpcrdma_create_id(struct rpcrdma_xprt *xprt,
 			__func__, rc);
 		goto put;
 	}
-	wait_for_completion_interruptible_timeout(&ia->ri_done,
-				msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1);
+	rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
+	if (rc < 0) {
+		dprintk("RPC:       %s: wait() exited: %i\n",
+			__func__, rc);
+		goto put;
+	}
 	rc = ia->ri_async_rc;
 	if (rc)
 		goto put;
@@ -532,7 +541,7 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
 	ep->rep_cqinit = ep->rep_attr.cap.max_send_wr/2 - 1;
 	if (ep->rep_cqinit <= 2)
 		ep->rep_cqinit = 0;	/* always signal? */
-	INIT_CQCOUNT(ep);
+	rpcrdma_init_cqcount(ep, 0);
 	init_waitqueue_head(&ep->rep_connect_wait);
 	INIT_DELAYED_WORK(&ep->rep_connect_worker, rpcrdma_connect_worker);
 
@@ -1311,13 +1320,7 @@ rpcrdma_ep_post(struct rpcrdma_ia *ia,
 	dprintk("RPC:       %s: posting %d s/g entries\n",
 		__func__, send_wr->num_sge);
 
-	if (DECR_CQCOUNT(ep) > 0)
-		send_wr->send_flags = 0;
-	else { /* Provider must take a send completion every now and then */
-		INIT_CQCOUNT(ep);
-		send_wr->send_flags = IB_SEND_SIGNALED;
-	}
-
+	rpcrdma_set_signaled(ep, send_wr);
 	rc = ib_post_send(ia->ri_id->qp, send_wr, &send_wr_fail);
 	if (rc)
 		goto out_postsend_err;
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index 6e1bba3..e35efd4 100644
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -75,6 +75,7 @@ struct rpcrdma_ia {
 	unsigned int		ri_max_inline_write;
 	unsigned int		ri_max_inline_read;
 	bool			ri_reminv_expected;
+	enum ib_mr_type		ri_mrtype;
 	struct ib_qp_attr	ri_qp_attr;
 	struct ib_qp_init_attr	ri_qp_init_attr;
 };
@@ -95,8 +96,24 @@ struct rpcrdma_ep {
 	struct delayed_work	rep_connect_worker;
 };
 
-#define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit)
-#define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount)
+static inline void
+rpcrdma_init_cqcount(struct rpcrdma_ep *ep, int count)
+{
+	atomic_set(&ep->rep_cqcount, ep->rep_cqinit - count);
+}
+
+/* To update send queue accounting, provider must take a
+ * send completion every now and then.
+ */
+static inline void
+rpcrdma_set_signaled(struct rpcrdma_ep *ep, struct ib_send_wr *send_wr)
+{
+	send_wr->send_flags = 0;
+	if (unlikely(atomic_sub_return(1, &ep->rep_cqcount) <= 0)) {
+		rpcrdma_init_cqcount(ep, 0);
+		send_wr->send_flags = IB_SEND_SIGNALED;
+	}
+}
 
 /* Pre-allocate extra Work Requests for handling backward receives
  * and sends. This is a fixed value because the Work Queues are
@@ -473,6 +490,7 @@ int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *,
 				struct rpcrdma_create_data_internal *);
 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *);
 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *);
+void rpcrdma_conn_func(struct rpcrdma_ep *ep);
 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *);
 
 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *,
@@ -532,13 +550,6 @@ rpcrdma_data_dir(bool writing)
 }
 
 /*
- * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c
- */
-void rpcrdma_connect_worker(struct work_struct *);
-void rpcrdma_conn_func(struct rpcrdma_ep *);
-void rpcrdma_reply_handler(struct work_struct *);
-
-/*
  * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
  */
 
@@ -555,12 +566,14 @@ bool rpcrdma_prepare_send_sges(struct rpcrdma_ia *, struct rpcrdma_req *,
 void rpcrdma_unmap_sges(struct rpcrdma_ia *, struct rpcrdma_req *);
 int rpcrdma_marshal_req(struct rpc_rqst *);
 void rpcrdma_set_max_header_sizes(struct rpcrdma_xprt *);
+void rpcrdma_reply_handler(struct work_struct *work);
 
 /* RPC/RDMA module init - xprtrdma/transport.c
  */
 extern unsigned int xprt_rdma_max_inline_read;
 void xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap);
 void xprt_rdma_free_addresses(struct rpc_xprt *xprt);
+void rpcrdma_connect_worker(struct work_struct *work);
 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq);
 int xprt_rdma_init(void);
 void xprt_rdma_cleanup(void);