1 files changed, 31 insertions, 71 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index c22d6b6f2db4..06ab4841537b 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -260,11 +260,16 @@ static int rdma_read_max_sge(struct svcxprt_rdma *xprt, int sge_count)
  * On our side, we need to read into a pagelist. The first page immediately
  * follows the RPC header.
  *
- * This function returns 1 to indicate success. The data is not yet in
+ * This function returns:
+ * 0 - No error and no read-list found.
+ *
+ * 1 - Successful read-list processing. The data is not yet in
  * the pagelist and therefore the RPC request must be deferred. The
  * I/O completion will enqueue the transport again and
  * svc_rdma_recvfrom will complete the request.
  *
+ * <0 - Error processing/posting read-list.
+ *
  * NOTE: The ctxt must not be touched after the last WR has been posted
  * because the I/O completion processing may occur on another
  * processor and free / modify the context. Ne touche pas!
@@ -284,7 +289,6 @@ static int rdma_read_xdr(struct svcxprt_rdma *xprt,
         u64 sgl_offset;
         struct rpcrdma_read_chunk *ch;
         struct svc_rdma_op_ctxt *ctxt = NULL;
-        struct svc_rdma_op_ctxt *head;
         struct svc_rdma_op_ctxt *tmp_sge_ctxt;
         struct svc_rdma_op_ctxt *tmp_ch_ctxt;
         struct chunk_sge *ch_sge_ary;
@@ -302,25 +306,19 @@ static int rdma_read_xdr(struct svcxprt_rdma *xprt,
         ch_sge_ary = (struct chunk_sge *)tmp_ch_ctxt->sge;
 
         svc_rdma_rcl_chunk_counts(ch, &ch_count, &byte_count);
+        if (ch_count > RPCSVC_MAXPAGES)
+                return -EINVAL;
         sge_count = rdma_rcl_to_sge(xprt, rqstp, hdr_ctxt, rmsgp,
                                     sge, ch_sge_ary,
                                     ch_count, byte_count);
-        head = svc_rdma_get_context(xprt);
         sgl_offset = 0;
         ch_no = 0;
 
         for (ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0];
              ch->rc_discrim != 0; ch++, ch_no++) {
 next_sge:
-                if (!ctxt)
-                        ctxt = head;
-                else {
-                        ctxt->next = svc_rdma_get_context(xprt);
-                        ctxt = ctxt->next;
-                }
-                ctxt->next = NULL;
+                ctxt = svc_rdma_get_context(xprt);
                 ctxt->direction = DMA_FROM_DEVICE;
-                clear_bit(RDMACTXT_F_READ_DONE, &ctxt->flags);
                 clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
 
                 /* Prepare READ WR */
@@ -347,20 +345,15 @@ next_sge:
                          * the client and the RPC needs to be enqueued.
                          */
                         set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags);
-                        ctxt->next = hdr_ctxt;
-                        hdr_ctxt->next = head;
+                        ctxt->read_hdr = hdr_ctxt;
                 }
                 /* Post the read */
                 err = svc_rdma_send(xprt, &read_wr);
                 if (err) {
-                        printk(KERN_ERR "svcrdma: Error posting send = %d\n",
+                        printk(KERN_ERR "svcrdma: Error %d posting RDMA_READ\n",
                                err);
-                        /*
-                         * Break the circular list so free knows when
-                         * to stop if the error happened to occur on
-                         * the last read
-                         */
-                        ctxt->next = NULL;
+                        set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
+                        svc_rdma_put_context(ctxt, 0);
                         goto out;
                 }
                 atomic_inc(&rdma_stat_read);
@@ -371,7 +364,7 @@ next_sge:
                         goto next_sge;
                 }
                 sgl_offset = 0;
-                err = 0;
+                err = 1;
         }
 
  out:
@@ -389,25 +382,12 @@ next_sge:
         while (rqstp->rq_resused)
                 rqstp->rq_respages[--rqstp->rq_resused] = NULL;
 
-        if (err) {
-                printk(KERN_ERR "svcrdma : RDMA_READ error = %d\n", err);
-                set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags);
-                /* Free the linked list of read contexts */
-                while (head != NULL) {
-                        ctxt = head->next;
-                        svc_rdma_put_context(head, 1);
-                        head = ctxt;
-                }
-                return 0;
-        }
-
-        return 1;
+        return err;
 }
 
 static int rdma_read_complete(struct svc_rqst *rqstp,
-                              struct svc_rdma_op_ctxt *data)
+                              struct svc_rdma_op_ctxt *head)
 {
-        struct svc_rdma_op_ctxt *head = data->next;
         int page_no;
         int ret;
 
@@ -433,21 +413,12 @@ static int rdma_read_complete(struct svc_rqst *rqstp,
         rqstp->rq_arg.len = head->arg.len;
         rqstp->rq_arg.buflen = head->arg.buflen;
 
+        /* Free the context */
+        svc_rdma_put_context(head, 0);
+
         /* XXX: What should this be? */
         rqstp->rq_prot = IPPROTO_MAX;
-
-        /*
-         * Free the contexts we used to build the RDMA_READ. We have
-         * to be careful here because the context list uses the same
-         * next pointer used to chain the contexts associated with the
-         * RDMA_READ
-         */
-        data->next = NULL;      /* terminate circular list */
-        do {
-                data = head->next;
-                svc_rdma_put_context(head, 0);
-                head = data;
-        } while (head != NULL);
+        svc_xprt_copy_addrs(rqstp, rqstp->rq_xprt);
 
         ret = rqstp->rq_arg.head[0].iov_len
                 + rqstp->rq_arg.page_len
@@ -457,8 +428,6 @@ static int rdma_read_complete(struct svc_rqst *rqstp,
                 ret, rqstp->rq_arg.len, rqstp->rq_arg.head[0].iov_base,
                 rqstp->rq_arg.head[0].iov_len);
 
-        /* Indicate that we've consumed an RQ credit */
-        rqstp->rq_xprt_ctxt = rqstp->rq_xprt;
         svc_xprt_received(rqstp->rq_xprt);
         return ret;
 }
@@ -480,13 +449,6 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
 
         dprintk("svcrdma: rqstp=%p\n", rqstp);
 
-        /*
-         * The rq_xprt_ctxt indicates if we've consumed an RQ credit
-         * or not. It is used in the rdma xpo_release_rqst function to
-         * determine whether or not to return an RQ WQE to the RQ.
-         */
-        rqstp->rq_xprt_ctxt = NULL;
-
         spin_lock_bh(&rdma_xprt->sc_read_complete_lock);
         if (!list_empty(&rdma_xprt->sc_read_complete_q)) {
                 ctxt = list_entry(rdma_xprt->sc_read_complete_q.next,
@@ -537,21 +499,22 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
         /* If the request is invalid, reply with an error */
         if (len < 0) {
                 if (len == -ENOSYS)
-                        (void)svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS);
+                        svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS);
                 goto close_out;
         }
 
-        /* Read read-list data. If we would need to wait, defer
-         * it. Not that in this case, we don't return the RQ credit
-         * until after the read completes.
-         */
-        if (rdma_read_xdr(rdma_xprt, rmsgp, rqstp, ctxt)) {
+        /* Read read-list data. */
+        ret = rdma_read_xdr(rdma_xprt, rmsgp, rqstp, ctxt);
+        if (ret > 0) {
+                /* read-list posted, defer until data received from client. */
                 svc_xprt_received(xprt);
                 return 0;
         }
-
-        /* Indicate we've consumed an RQ credit */
-        rqstp->rq_xprt_ctxt = rqstp->rq_xprt;
+        if (ret < 0) {
+                /* Post of read-list failed, free context. */
+                svc_rdma_put_context(ctxt, 1);
+                return 0;
+        }
 
         ret = rqstp->rq_arg.head[0].iov_len
                 + rqstp->rq_arg.page_len
@@ -569,11 +532,8 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
         return ret;
 
  close_out:
-        if (ctxt) {
+        if (ctxt)
                 svc_rdma_put_context(ctxt, 1);
-                /* Indicate we've consumed an RQ credit */
-                rqstp->rq_xprt_ctxt = rqstp->rq_xprt;
-        }
         dprintk("svcrdma: transport %p is closing\n", xprt);
         /*
          * Set the close bit and enqueue it. svc_recv will see the