svcrdma: svc_rdma_put_context() is invoked twice in Send error path

Get a fresh op_ctxt in send_reply() instead of in svc_rdma_sendto().
This ensures that svc_rdma_put_context() is invoked only once if
send_reply() fails.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 13 insertions, 15 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index 4f1b1c4f45f9..54d533300620 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -463,25 +463,21 @@ static int send_reply(struct svcxprt_rdma *rdma,
                       struct svc_rqst *rqstp,
                       struct page *page,
                       struct rpcrdma_msg *rdma_resp,
-                      struct svc_rdma_op_ctxt *ctxt,
                       struct svc_rdma_req_map *vec,
                       int byte_count)
 {
+        struct svc_rdma_op_ctxt *ctxt;
         struct ib_send_wr send_wr;
         u32 xdr_off;
         int sge_no;
         int sge_bytes;
         int page_no;
         int pages;
-        int ret;
-
-        ret = svc_rdma_repost_recv(rdma, GFP_KERNEL);
-        if (ret) {
-                svc_rdma_put_context(ctxt, 0);
-                return -ENOTCONN;
-        }
+        int ret = -EIO;
 
         /* Prepare the context */
+        ctxt = svc_rdma_get_context(rdma);
+        ctxt->direction = DMA_TO_DEVICE;
         ctxt->pages[0] = page;
         ctxt->count = 1;
 
@@ -565,8 +561,7 @@ static int send_reply(struct svcxprt_rdma *rdma,
  err:
         svc_rdma_unmap_dma(ctxt);
         svc_rdma_put_context(ctxt, 1);
-        pr_err("svcrdma: failed to send reply, rc=%d\n", ret);
-        return -EIO;
+        return ret;
 }
 
 void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp)
@@ -585,7 +580,6 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
         int ret;
         int inline_bytes;
         struct page *res_page;
-        struct svc_rdma_op_ctxt *ctxt;
         struct svc_rdma_req_map *vec;
 
         dprintk("svcrdma: sending response for rqstp=%p\n", rqstp);
@@ -598,8 +592,6 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
         rp_ary = svc_rdma_get_reply_array(rdma_argp, wr_ary);
 
         /* Build an req vec for the XDR */
-        ctxt = svc_rdma_get_context(rdma);
-        ctxt->direction = DMA_TO_DEVICE;
         vec = svc_rdma_get_req_map(rdma);
         ret = svc_rdma_map_xdr(rdma, &rqstp->rq_res, vec, wr_ary != NULL);
         if (ret)
@@ -635,7 +627,12 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
                 inline_bytes -= ret;
         }
 
-        ret = send_reply(rdma, rqstp, res_page, rdma_resp, ctxt, vec,
+        /* Post a fresh Receive buffer _before_ sending the reply */
+        ret = svc_rdma_post_recv(rdma, GFP_KERNEL);
+        if (ret)
+                goto err1;
+
+        ret = send_reply(rdma, rqstp, res_page, rdma_resp, vec,
                          inline_bytes);
         if (ret < 0)
                 goto err1;
@@ -648,7 +645,8 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
         put_page(res_page);
  err0:
         svc_rdma_put_req_map(rdma, vec);
-        svc_rdma_put_context(ctxt, 0);
+        pr_err("svcrdma: Could not send reply, err=%d. Closing transport.\n",
+               ret);
         set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags);
         return -ENOTCONN;
 }