1 files changed, 112 insertions, 32 deletions

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 40b502b11442..a4fafcbc6ea0 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -387,6 +387,33 @@ static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
         return len;
 }
 
+static int svc_partial_recvfrom(struct svc_rqst *rqstp,
+                                struct kvec *iov, int nr,
+                                int buflen, unsigned int base)
+{
+        size_t save_iovlen;
+        void __user *save_iovbase;
+        unsigned int i;
+        int ret;
+
+        if (base == 0)
+                return svc_recvfrom(rqstp, iov, nr, buflen);
+
+        for (i = 0; i < nr; i++) {
+                if (iov[i].iov_len > base)
+                        break;
+                base -= iov[i].iov_len;
+        }
+        save_iovlen = iov[i].iov_len;
+        save_iovbase = iov[i].iov_base;
+        iov[i].iov_len -= base;
+        iov[i].iov_base += base;
+        ret = svc_recvfrom(rqstp, &iov[i], nr - i, buflen);
+        iov[i].iov_len = save_iovlen;
+        iov[i].iov_base = save_iovbase;
+        return ret;
+}
+
 /*
  * Set socket snd and rcv buffer lengths
  */
@@ -884,6 +911,56 @@ failed:
         return NULL;
 }
 
+static unsigned int svc_tcp_restore_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
+{
+        unsigned int i, len, npages;
+
+        if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
+                return 0;
+        len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
+        npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+        for (i = 0; i < npages; i++) {
+                if (rqstp->rq_pages[i] != NULL)
+                        put_page(rqstp->rq_pages[i]);
+                BUG_ON(svsk->sk_pages[i] == NULL);
+                rqstp->rq_pages[i] = svsk->sk_pages[i];
+                svsk->sk_pages[i] = NULL;
+        }
+        rqstp->rq_arg.head[0].iov_base = page_address(rqstp->rq_pages[0]);
+        return len;
+}
+
+static void svc_tcp_save_pages(struct svc_sock *svsk, struct svc_rqst *rqstp)
+{
+        unsigned int i, len, npages;
+
+        if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
+                return;
+        len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
+        npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+        for (i = 0; i < npages; i++) {
+                svsk->sk_pages[i] = rqstp->rq_pages[i];
+                rqstp->rq_pages[i] = NULL;
+        }
+}
+
+static void svc_tcp_clear_pages(struct svc_sock *svsk)
+{
+        unsigned int i, len, npages;
+
+        if (svsk->sk_tcplen <= sizeof(rpc_fraghdr))
+                goto out;
+        len = svsk->sk_tcplen - sizeof(rpc_fraghdr);
+        npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+        for (i = 0; i < npages; i++) {
+                BUG_ON(svsk->sk_pages[i] == NULL);
+                put_page(svsk->sk_pages[i]);
+                svsk->sk_pages[i] = NULL;
+        }
+out:
+        svsk->sk_tcplen = 0;
+}
+
 /*
  * Receive data.
  * If we haven't gotten the record length yet, get the next four bytes.
@@ -928,7 +1005,7 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
                 if (len < want) {
                         dprintk("svc: short recvfrom while reading record "
                                 "length (%d of %d)\n", len, want);
-                        goto err_again; /* record header not complete */
+                        return -EAGAIN;
                 }
 
                 svsk->sk_reclen = ntohl(svsk->sk_reclen);
@@ -958,26 +1035,14 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
         if (svsk->sk_reclen < 8)
                 goto err_delete; /* client is nuts. */
 
-        /* Check whether enough data is available */
-        len = svc_recv_available(svsk);
-        if (len < 0)
-                goto error;
-
-        if (len < svsk->sk_reclen) {
-                dprintk("svc: incomplete TCP record (%d of %d)\n",
-                        len, svsk->sk_reclen);
-                goto err_again; /* record not complete */
-        }
         len = svsk->sk_reclen;
 
         return len;
- error:
-        if (len == -EAGAIN)
-                dprintk("RPC: TCP recv_record got EAGAIN\n");
+error:
+        dprintk("RPC: TCP recv_record got %d\n", len);
         return len;
- err_delete:
+err_delete:
         set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
- err_again:
         return -EAGAIN;
 }
 
@@ -1035,6 +1100,7 @@ static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)
         return i;
 }
 
+
 /*
  * Receive data from a TCP socket.
  */
@@ -1045,6 +1111,7 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
         struct svc_serv *serv = svsk->sk_xprt.xpt_server;
         int             len;
         struct kvec *vec;
+        unsigned int want, base;
         __be32 *p;
         __be32 calldir;
         int pnum;
@@ -1058,6 +1125,9 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
         if (len < 0)
                 goto error;
 
+        base = svc_tcp_restore_pages(svsk, rqstp);
+        want = svsk->sk_reclen - base;
+
         vec = rqstp->rq_vec;
 
         pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
@@ -1066,11 +1136,18 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
         rqstp->rq_respages = &rqstp->rq_pages[pnum];
 
         /* Now receive data */
-        len = svc_recvfrom(rqstp, vec, pnum, svsk->sk_reclen);
-        if (len < 0)
-                goto err_again;
+        len = svc_partial_recvfrom(rqstp, vec, pnum, want, base);
+        if (len >= 0)
+                svsk->sk_tcplen += len;
+        if (len != want) {
+                if (len < 0 && len != -EAGAIN)
+                        goto err_other;
+                svc_tcp_save_pages(svsk, rqstp);
+                dprintk("svc: incomplete TCP record (%d of %d)\n",
+                        svsk->sk_tcplen, svsk->sk_reclen);
+                goto err_noclose;
+        }
 
-        dprintk("svc: TCP complete record (%d bytes)\n", svsk->sk_reclen);
         rqstp->rq_arg.len = svsk->sk_reclen;
         rqstp->rq_arg.page_base = 0;
         if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
@@ -1087,7 +1164,7 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
         if (calldir) {
                 len = receive_cb_reply(svsk, rqstp);
                 if (len < 0)
-                        goto err_again;
+                        goto error;
         }
 
         /* Reset TCP read info */
@@ -1102,20 +1179,20 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
         if (serv->sv_stats)
                 serv->sv_stats->nettcpcnt++;
 
+        dprintk("svc: TCP complete record (%d bytes)\n", rqstp->rq_arg.len);
         return rqstp->rq_arg.len;
 
-err_again:
-        if (len == -EAGAIN) {
-                dprintk("RPC: TCP recvfrom got EAGAIN\n");
-                return len;
-        }
 error:
-        if (len != -EAGAIN) {
-                printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
-                       svsk->sk_xprt.xpt_server->sv_name, -len);
-                set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
-        }
+        if (len != -EAGAIN)
+                goto err_other;
+        dprintk("RPC: TCP recvfrom got EAGAIN\n");
         return -EAGAIN;
+err_other:
+        printk(KERN_NOTICE "%s: recvfrom returned errno %d\n",
+               svsk->sk_xprt.xpt_server->sv_name, -len);
+        set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
+err_noclose:
+        return -EAGAIN; /* record not complete */
 }
 
 /*
@@ -1286,6 +1363,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
 
                 svsk->sk_reclen = 0;
                 svsk->sk_tcplen = 0;
+                memset(&svsk->sk_pages[0], 0, sizeof(svsk->sk_pages));
 
                 tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
 
@@ -1544,8 +1622,10 @@ static void svc_tcp_sock_detach(struct svc_xprt *xprt)
 
         svc_sock_detach(xprt);
 
-        if (!test_bit(XPT_LISTENER, &xprt->xpt_flags))
+        if (!test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
+                svc_tcp_clear_pages(svsk);
                 kernel_sock_shutdown(svsk->sk_sock, SHUT_RDWR);
+        }
 }
 
 /*