SUNRPC: Update RPC server's TCP record marker decoder

Clean up: Update the RPC server's TCP record marker decoder to match the
constructs used by the RPC client's TCP socket transport.

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

include/linux/sunrpc/svcsock.h

@@ -26,8 +26,8 @@ struct svc_sock {
 	void			(*sk_owspace)(struct sock *);
 
 	/* private TCP part */
-	int			sk_reclen;	/* length of record */
-	int			sk_tcplen;	/* current read length */
+	u32			sk_reclen;	/* length of record */
+	u32			sk_tcplen;	/* current read length */
 };
 
 /*

net/sunrpc/svcsock.c

@@ -46,6 +46,7 @@
 #include <linux/sunrpc/types.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/xdr.h>
+#include <linux/sunrpc/msg_prot.h>
 #include <linux/sunrpc/svcsock.h>
 #include <linux/sunrpc/stats.h>
 
@@ -823,8 +824,8 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
 	 * the next four bytes. Otherwise try to gobble up as much as
 	 * possible up to the complete record length.
 	 */
-	if (svsk->sk_tcplen < 4) {
-		unsigned long	want = 4 - svsk->sk_tcplen;
+	if (svsk->sk_tcplen < sizeof(rpc_fraghdr)) {
+		int		want = sizeof(rpc_fraghdr) - svsk->sk_tcplen;
 		struct kvec	iov;
 
 		iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen;
@@ -834,32 +835,31 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
 		svsk->sk_tcplen += len;
 
 		if (len < want) {
-			dprintk("svc: short recvfrom while reading record length (%d of %lu)\n",
-				len, want);
+			dprintk("svc: short recvfrom while reading record "
+				"length (%d of %d)\n", len, want);
 			svc_xprt_received(&svsk->sk_xprt);
 			return -EAGAIN; /* record header not complete */
 		}
 
 		svsk->sk_reclen = ntohl(svsk->sk_reclen);
-		if (!(svsk->sk_reclen & 0x80000000)) {
+		if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
 			/* FIXME: technically, a record can be fragmented,
 			 *  and non-terminal fragments will not have the top
 			 *  bit set in the fragment length header.
 			 *  But apparently no known nfs clients send fragmented
 			 *  records. */
 			if (net_ratelimit())
-				printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx"
-				       " (non-terminal)\n",
-				       (unsigned long) svsk->sk_reclen);
+				printk(KERN_NOTICE "RPC: multiple fragments "
+					"per record not supported\n");
 			goto err_delete;
 		}
-		svsk->sk_reclen &= 0x7fffffff;
+		svsk->sk_reclen &= RPC_FRAGMENT_SIZE_MASK;
 		dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen);
 		if (svsk->sk_reclen > serv->sv_max_mesg) {
 			if (net_ratelimit())
-				printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx"
-				       " (large)\n",
-				       (unsigned long) svsk->sk_reclen);
+				printk(KERN_NOTICE "RPC: "
+					"fragment too large: 0x%08lx\n",
+					(unsigned long)svsk->sk_reclen);
 			goto err_delete;
 		}
 	}