1 files changed, 69 insertions, 86 deletions

diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index a60b4c4d9886..c09f1b6c3f0a 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -926,44 +926,18 @@ rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
 {
 	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
 	struct rpcrdma_ia *ia = &r_xprt->rx_ia;
-	struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
-	char *p;
-	size_t len;
 	int i, rc;
 
-	buf->rb_max_requests = cdata->max_requests;
+	buf->rb_max_requests = r_xprt->rx_data.max_requests;
 	spin_lock_init(&buf->rb_lock);
 
-	/* Need to allocate:
-	 *   1.  arrays for send and recv pointers
-	 *   2.  arrays of struct rpcrdma_req to fill in pointers
-	 *   3.  array of struct rpcrdma_rep for replies
-	 * Send/recv buffers in req/rep need to be registered
-	 */
-	len = buf->rb_max_requests *
-		(sizeof(struct rpcrdma_req *) + sizeof(struct rpcrdma_rep *));
-
-	p = kzalloc(len, GFP_KERNEL);
-	if (p == NULL) {
-		dprintk("RPC:       %s: req_t/rep_t/pad kzalloc(%zd) failed\n",
-			__func__, len);
-		rc = -ENOMEM;
-		goto out;
-	}
-	buf->rb_pool = p;	/* for freeing it later */
-
-	buf->rb_send_bufs = (struct rpcrdma_req **) p;
-	p = (char *) &buf->rb_send_bufs[buf->rb_max_requests];
-	buf->rb_recv_bufs = (struct rpcrdma_rep **) p;
-	p = (char *) &buf->rb_recv_bufs[buf->rb_max_requests];
-
 	rc = ia->ri_ops->ro_init(r_xprt);
 	if (rc)
 		goto out;
 
+	INIT_LIST_HEAD(&buf->rb_send_bufs);
 	for (i = 0; i < buf->rb_max_requests; i++) {
 		struct rpcrdma_req *req;
-		struct rpcrdma_rep *rep;
 
 		req = rpcrdma_create_req(r_xprt);
 		if (IS_ERR(req)) {
@@ -972,7 +946,12 @@ rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
 			rc = PTR_ERR(req);
 			goto out;
 		}
-		buf->rb_send_bufs[i] = req;
+		list_add(&req->rl_free, &buf->rb_send_bufs);
+	}
+
+	INIT_LIST_HEAD(&buf->rb_recv_bufs);
+	for (i = 0; i < buf->rb_max_requests + 2; i++) {
+		struct rpcrdma_rep *rep;
 
 		rep = rpcrdma_create_rep(r_xprt);
 		if (IS_ERR(rep)) {
@@ -981,7 +960,7 @@ rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
 			rc = PTR_ERR(rep);
 			goto out;
 		}
-		buf->rb_recv_bufs[i] = rep;
+		list_add(&rep->rr_list, &buf->rb_recv_bufs);
 	}
 
 	return 0;
@@ -990,6 +969,28 @@ out:
 	return rc;
 }
 
+static struct rpcrdma_req *
+rpcrdma_buffer_get_req_locked(struct rpcrdma_buffer *buf)
+{
+	struct rpcrdma_req *req;
+
+	req = list_first_entry(&buf->rb_send_bufs,
+			       struct rpcrdma_req, rl_free);
+	list_del(&req->rl_free);
+	return req;
+}
+
+static struct rpcrdma_rep *
+rpcrdma_buffer_get_rep_locked(struct rpcrdma_buffer *buf)
+{
+	struct rpcrdma_rep *rep;
+
+	rep = list_first_entry(&buf->rb_recv_bufs,
+			       struct rpcrdma_rep, rr_list);
+	list_del(&rep->rr_list);
+	return rep;
+}
+
 static void
 rpcrdma_destroy_rep(struct rpcrdma_ia *ia, struct rpcrdma_rep *rep)
 {
@@ -1015,25 +1016,22 @@ void
 rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
 {
 	struct rpcrdma_ia *ia = rdmab_to_ia(buf);
-	int i;
 
-	/* clean up in reverse order from create
-	 *   1.  recv mr memory (mr free, then kfree)
-	 *   2.  send mr memory (mr free, then kfree)
-	 *   3.  MWs
-	 */
-	dprintk("RPC:       %s: entering\n", __func__);
+	while (!list_empty(&buf->rb_recv_bufs)) {
+		struct rpcrdma_rep *rep;
 
-	for (i = 0; i < buf->rb_max_requests; i++) {
-		if (buf->rb_recv_bufs)
-			rpcrdma_destroy_rep(ia, buf->rb_recv_bufs[i]);
-		if (buf->rb_send_bufs)
-			rpcrdma_destroy_req(ia, buf->rb_send_bufs[i]);
+		rep = rpcrdma_buffer_get_rep_locked(buf);
+		rpcrdma_destroy_rep(ia, rep);
 	}
 
-	ia->ri_ops->ro_destroy(buf);
+	while (!list_empty(&buf->rb_send_bufs)) {
+		struct rpcrdma_req *req;
 
-	kfree(buf->rb_pool);
+		req = rpcrdma_buffer_get_req_locked(buf);
+		rpcrdma_destroy_req(ia, req);
+	}
+
+	ia->ri_ops->ro_destroy(buf);
 }
 
 struct rpcrdma_mw *
@@ -1065,25 +1063,10 @@ rpcrdma_put_mw(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mw *mw)
 	spin_unlock(&buf->rb_mwlock);
 }
 
-static void
-rpcrdma_buffer_put_sendbuf(struct rpcrdma_req *req, struct rpcrdma_buffer *buf)
-{
-	buf->rb_send_bufs[--buf->rb_send_index] = req;
-	req->rl_niovs = 0;
-	if (req->rl_reply) {
-		buf->rb_recv_bufs[--buf->rb_recv_index] = req->rl_reply;
-		req->rl_reply = NULL;
-	}
-}
-
 /*
  * Get a set of request/reply buffers.
  *
- * Reply buffer (if needed) is attached to send buffer upon return.
- * Rule:
- *    rb_send_index and rb_recv_index MUST always be pointing to the
- *    *next* available buffer (non-NULL). They are incremented after
- *    removing buffers, and decremented *before* returning them.
+ * Reply buffer (if available) is attached to send buffer upon return.
  */
 struct rpcrdma_req *
 rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
@@ -1092,26 +1075,23 @@ rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
 	unsigned long flags;
 
 	spin_lock_irqsave(&buffers->rb_lock, flags);
+	if (list_empty(&buffers->rb_send_bufs))
+		goto out_reqbuf;
+	req = rpcrdma_buffer_get_req_locked(buffers);
+	if (list_empty(&buffers->rb_recv_bufs))
+		goto out_repbuf;
+	req->rl_reply = rpcrdma_buffer_get_rep_locked(buffers);
+	spin_unlock_irqrestore(&buffers->rb_lock, flags);
+	return req;
 
-	if (buffers->rb_send_index == buffers->rb_max_requests) {
-		spin_unlock_irqrestore(&buffers->rb_lock, flags);
-		dprintk("RPC:       %s: out of request buffers\n", __func__);
-		return ((struct rpcrdma_req *)NULL);
-	}
-
-	req = buffers->rb_send_bufs[buffers->rb_send_index];
-	if (buffers->rb_send_index < buffers->rb_recv_index) {
-		dprintk("RPC:       %s: %d extra receives outstanding (ok)\n",
-			__func__,
-			buffers->rb_recv_index - buffers->rb_send_index);
-		req->rl_reply = NULL;
-	} else {
-		req->rl_reply = buffers->rb_recv_bufs[buffers->rb_recv_index];
-		buffers->rb_recv_bufs[buffers->rb_recv_index++] = NULL;
-	}
-	buffers->rb_send_bufs[buffers->rb_send_index++] = NULL;
-
+out_reqbuf:
+	spin_unlock_irqrestore(&buffers->rb_lock, flags);
+	pr_warn("RPC:       %s: out of request buffers\n", __func__);
+	return NULL;
+out_repbuf:
 	spin_unlock_irqrestore(&buffers->rb_lock, flags);
+	pr_warn("RPC:       %s: out of reply buffers\n", __func__);
+	req->rl_reply = NULL;
 	return req;
 }
 
@@ -1123,17 +1103,22 @@ void
 rpcrdma_buffer_put(struct rpcrdma_req *req)
 {
 	struct rpcrdma_buffer *buffers = req->rl_buffer;
+	struct rpcrdma_rep *rep = req->rl_reply;
 	unsigned long flags;
 
+	req->rl_niovs = 0;
+	req->rl_reply = NULL;
+
 	spin_lock_irqsave(&buffers->rb_lock, flags);
-	rpcrdma_buffer_put_sendbuf(req, buffers);
+	list_add_tail(&req->rl_free, &buffers->rb_send_bufs);
+	if (rep)
+		list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
 	spin_unlock_irqrestore(&buffers->rb_lock, flags);
 }
 
 /*
  * Recover reply buffers from pool.
- * This happens when recovering from error conditions.
- * Post-increment counter/array index.
+ * This happens when recovering from disconnect.
  */
 void
 rpcrdma_recv_buffer_get(struct rpcrdma_req *req)
@@ -1142,10 +1127,8 @@ rpcrdma_recv_buffer_get(struct rpcrdma_req *req)
 	unsigned long flags;
 
 	spin_lock_irqsave(&buffers->rb_lock, flags);
-	if (buffers->rb_recv_index < buffers->rb_max_requests) {
-		req->rl_reply = buffers->rb_recv_bufs[buffers->rb_recv_index];
-		buffers->rb_recv_bufs[buffers->rb_recv_index++] = NULL;
-	}
+	if (!list_empty(&buffers->rb_recv_bufs))
+		req->rl_reply = rpcrdma_buffer_get_rep_locked(buffers);
 	spin_unlock_irqrestore(&buffers->rb_lock, flags);
 }
 
@@ -1160,7 +1143,7 @@ rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
 	unsigned long flags;
 
 	spin_lock_irqsave(&buffers->rb_lock, flags);
-	buffers->rb_recv_bufs[--buffers->rb_recv_index] = rep;
+	list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
 	spin_unlock_irqrestore(&buffers->rb_lock, flags);
 }