[IB] simplify mad_rmpp.c:alloc_response_msg()

Change alloc_response_msg() in mad_rmpp.c to return the struct
it allocates directly (or an error code a la ERR_PTR), rather than
returning a status and passing the struct back in a pointer param.
This simplifies the code and gets rid of warnings like

    drivers/infiniband/core/mad_rmpp.c: In function nack_recv:
    drivers/infiniband/core/mad_rmpp.c:192: warning: msg may be used uninitialized in this function

with newer versions of gcc.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 15 insertions, 16 deletions

diff --git a/drivers/infiniband/core/mad_rmpp.c b/drivers/infiniband/core/mad_rmpp.c
index ba112cd5f93c..3249e1d8c07b 100644
--- a/drivers/infiniband/core/mad_rmpp.c
+++ b/drivers/infiniband/core/mad_rmpp.c
@@ -151,28 +151,27 @@ static void ack_recv(struct mad_rmpp_recv *rmpp_recv,
                 ib_free_send_mad(msg);
 }
 
-static int alloc_response_msg(struct ib_mad_agent *agent,
-                              struct ib_mad_recv_wc *recv_wc,
-                              struct ib_mad_send_buf **msg)
+static struct ib_mad_send_buf *alloc_response_msg(struct ib_mad_agent *agent,
+                                                  struct ib_mad_recv_wc *recv_wc)
 {
-        struct ib_mad_send_buf *m;
+        struct ib_mad_send_buf *msg;
         struct ib_ah *ah;
 
         ah = ib_create_ah_from_wc(agent->qp->pd, recv_wc->wc,
                                   recv_wc->recv_buf.grh, agent->port_num);
         if (IS_ERR(ah))
-                return PTR_ERR(ah);
+                return (void *) ah;
 
-        m = ib_create_send_mad(agent, recv_wc->wc->src_qp,
-                               recv_wc->wc->pkey_index, 1,
-                               IB_MGMT_RMPP_HDR, IB_MGMT_RMPP_DATA, GFP_KERNEL);
-        if (IS_ERR(m)) {
+        msg = ib_create_send_mad(agent, recv_wc->wc->src_qp,
+                                 recv_wc->wc->pkey_index, 1,
+                                 IB_MGMT_RMPP_HDR, IB_MGMT_RMPP_DATA,
+                                 GFP_KERNEL);
+        if (IS_ERR(msg))
                 ib_destroy_ah(ah);
-                return PTR_ERR(m);
-        }
-        m->ah = ah;
-        *msg = m;
-        return 0;
+        else
+                msg->ah = ah;
+
+        return msg;
 }
 
 void ib_rmpp_send_handler(struct ib_mad_send_wc *mad_send_wc)
@@ -191,8 +190,8 @@ static void nack_recv(struct ib_mad_agent_private *agent,
         struct ib_rmpp_mad *rmpp_mad;
         int ret;
 
-        ret = alloc_response_msg(&agent->agent, recv_wc, &msg);
-        if (ret)
+        msg = alloc_response_msg(&agent->agent, recv_wc);
+        if (IS_ERR(msg))
                 return;
 
         rmpp_mad = msg->mad;