1 files changed, 38 insertions, 24 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 396cdbe249d1..12487aafaab5 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -36,8 +36,6 @@
 #include <linux/sunrpc/metrics.h>
 
 
-#define RPC_SLACK_SPACE         (1024)  /* total overkill */
-
 #ifdef RPC_DEBUG
 # define RPCDBG_FACILITY        RPCDBG_CALL
 #endif
@@ -747,21 +745,37 @@ call_reserveresult(struct rpc_task *task)
 static void
 call_allocate(struct rpc_task *task)
 {
+        unsigned int slack = task->tk_auth->au_cslack;
         struct rpc_rqst *req = task->tk_rqstp;
         struct rpc_xprt *xprt = task->tk_xprt;
-        unsigned int    bufsiz;
+        struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
 
         dprint_status(task);
 
+        task->tk_status = 0;
         task->tk_action = call_bind;
+
         if (req->rq_buffer)
                 return;
 
-        /* FIXME: compute buffer requirements more exactly using
-         * auth->au_wslack */
-        bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE;
+        if (proc->p_proc != 0) {
+                BUG_ON(proc->p_arglen == 0);
+                if (proc->p_decode != NULL)
+                        BUG_ON(proc->p_replen == 0);
+        }
 
-        if (xprt->ops->buf_alloc(task, bufsiz << 1) != NULL)
+        /*
+         * Calculate the size (in quads) of the RPC call
+         * and reply headers, and convert both values
+         * to byte sizes.
+         */
+        req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
+        req->rq_callsize <<= 2;
+        req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
+        req->rq_rcvsize <<= 2;
+
+        xprt->ops->buf_alloc(task, req->rq_callsize + req->rq_rcvsize);
+        if (req->rq_buffer != NULL)
                 return;
 
         dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
@@ -788,6 +802,17 @@ rpc_task_force_reencode(struct rpc_task *task)
         task->tk_rqstp->rq_snd_buf.len = 0;
 }
 
+static inline void
+rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
+{
+        buf->head[0].iov_base = start;
+        buf->head[0].iov_len = len;
+        buf->tail[0].iov_len = 0;
+        buf->page_len = 0;
+        buf->len = 0;
+        buf->buflen = len;
+}
+
 /*
  * 3.   Encode arguments of an RPC call
  */
@@ -795,28 +820,17 @@ static void
 call_encode(struct rpc_task *task)
 {
         struct rpc_rqst *req = task->tk_rqstp;
-        struct xdr_buf *sndbuf = &req->rq_snd_buf;
-        struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
-        unsigned int    bufsiz;
         kxdrproc_t      encode;
         __be32          *p;
 
         dprint_status(task);
 
-        /* Default buffer setup */
-        bufsiz = req->rq_bufsize >> 1;
-        sndbuf->head[0].iov_base = (void *)req->rq_buffer;
-        sndbuf->head[0].iov_len  = bufsiz;
-        sndbuf->tail[0].iov_len  = 0;
-        sndbuf->page_len         = 0;
-        sndbuf->len              = 0;
-        sndbuf->buflen           = bufsiz;
-        rcvbuf->head[0].iov_base = (void *)((char *)req->rq_buffer + bufsiz);
-        rcvbuf->head[0].iov_len  = bufsiz;
-        rcvbuf->tail[0].iov_len  = 0;
-        rcvbuf->page_len         = 0;
-        rcvbuf->len              = 0;
-        rcvbuf->buflen           = bufsiz;
+        rpc_xdr_buf_init(&req->rq_snd_buf,
+                         req->rq_buffer,
+                         req->rq_callsize);
+        rpc_xdr_buf_init(&req->rq_rcv_buf,
+                         (char *)req->rq_buffer + req->rq_callsize,
+                         req->rq_rcvsize);
 
         /* Encode header and provided arguments */
         encode = task->tk_msg.rpc_proc->p_encode;