9P/RDMA: Improve error handling in rdma_request

Most importantly:
- do not free the recv context (rpl_context) after a successful post_recv()
- but do free the send context (c) after a failed send.

Signed-off-by: Simon Derr <simon.derr@bull.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>

1 files changed, 28 insertions, 16 deletions

diff --git a/net/9p/trans_rdma.c b/net/9p/trans_rdma.c
index 1bd4c7150114..926e72d00e57 100644
--- a/net/9p/trans_rdma.c
+++ b/net/9p/trans_rdma.c
@@ -430,7 +430,7 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req)
         rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS);
         if (!rpl_context) {
                 err = -ENOMEM;
-                goto err_close;
+                goto recv_error;
         }
         rpl_context->rc = req->rc;
 
@@ -441,13 +441,15 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req)
          * outstanding request, so we must keep a count to avoid
          * overflowing the RQ.
          */
-        if (down_interruptible(&rdma->rq_sem))
-                goto error; /* FIXME : -EINTR instead */
+        if (down_interruptible(&rdma->rq_sem)) {
+                err = -EINTR;
+                goto recv_error;
+        }
 
         err = post_recv(client, rpl_context);
         if (err) {
                 p9_debug(P9_DEBUG_FCALL, "POST RECV failed\n");
-                goto err_free;
+                goto recv_error;
         }
 
         /* remove posted receive buffer from request structure */
@@ -457,15 +459,17 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req)
         c = kmalloc(sizeof *c, GFP_NOFS);
         if (!c) {
                 err = -ENOMEM;
-                goto err_free;
+                goto send_error;
         }
         c->req = req;
 
         c->busa = ib_dma_map_single(rdma->cm_id->device,
                                     c->req->tc->sdata, c->req->tc->size,
                                     DMA_TO_DEVICE);
-        if (ib_dma_mapping_error(rdma->cm_id->device, c->busa))
-                goto error;
+        if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) {
+                err = -EIO;
+                goto send_error;
+        }
 
         sge.addr = c->busa;
         sge.length = c->req->tc->size;
@@ -479,19 +483,27 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req)
         wr.sg_list = &sge;
         wr.num_sge = 1;
 
-        if (down_interruptible(&rdma->sq_sem))
-                goto error;
+        if (down_interruptible(&rdma->sq_sem)) {
+                err = -EINTR;
+                goto send_error;
+        }
 
-        return ib_post_send(rdma->qp, &wr, &bad_wr);
+        err = ib_post_send(rdma->qp, &wr, &bad_wr);
+        if (err)
+                goto send_error;
 
- error:
+        /* Success */
+        return 0;
+
+ /* Handle errors that happened during or while preparing the send: */
+ send_error:
         kfree(c);
+        p9_debug(P9_DEBUG_ERROR, "Error %d in rdma_request()\n", err);
+        return err;
+
+ /* Handle errors that happened during or while preparing post_recv(): */
+ recv_error:
         kfree(rpl_context);
-        p9_debug(P9_DEBUG_ERROR, "EIO\n");
-        return -EIO;
- err_free:
-        kfree(rpl_context);
- err_close:
         spin_lock_irqsave(&rdma->req_lock, flags);
         if (rdma->state < P9_RDMA_CLOSING) {
                 rdma->state = P9_RDMA_CLOSING;