svcrpc: don't byte-swap sk_reclen in place
authorJ. Bruce Fields <bfields@redhat.com>
Mon, 3 Dec 2012 21:11:13 +0000 (16:11 -0500)
committerJ. Bruce Fields <bfields@redhat.com>
Tue, 4 Dec 2012 12:47:23 +0000 (07:47 -0500)
Byte-swapping in place is always a little dubious.

Let's instead define this field to always be big-endian, and do the
swapping on demand where we need it.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
include/linux/sunrpc/svcsock.h
net/sunrpc/svcsock.c

index 92ad02f0dcc0ea9409a09c1b3637e1f5c1869bc1..613cf42227aa35237c27e2b956100545ab36631f 100644 (file)
@@ -26,11 +26,21 @@ struct svc_sock {
        void                    (*sk_owspace)(struct sock *);
 
        /* private TCP part */
-       u32                     sk_reclen;      /* length of record */
+       __be32                  sk_reclen;      /* length of record */
        u32                     sk_tcplen;      /* current read length */
        struct page *           sk_pages[RPCSVC_MAXPAGES];      /* received data */
 };
 
+static inline u32 svc_sock_reclen(struct svc_sock *svsk)
+{
+       return ntohl(svsk->sk_reclen) & RPC_FRAGMENT_SIZE_MASK;
+}
+
+static inline u32 svc_sock_final_rec(struct svc_sock *svsk)
+{
+       return ntohl(svsk->sk_reclen) & RPC_LAST_STREAM_FRAGMENT;
+}
+
 /*
  * Function prototypes.
  */
index 03827cef1fa783174409e23b2241bba903809e3a..d50de2b95036d0ff9238a64484fc5d16ac66d1a2 100644 (file)
@@ -950,8 +950,7 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
                        return -EAGAIN;
                }
 
-               svsk->sk_reclen = ntohl(svsk->sk_reclen);
-               if (!(svsk->sk_reclen & RPC_LAST_STREAM_FRAGMENT)) {
+               if (!(svc_sock_final_rec(svsk))) {
                        /* FIXME: technically, a record can be fragmented,
                         *  and non-terminal fragments will not have the top
                         *  bit set in the fragment length header.
@@ -961,21 +960,18 @@ static int svc_tcp_recv_record(struct svc_sock *svsk, struct svc_rqst *rqstp)
                        goto err_delete;
                }
 
-               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) {
+               dprintk("svc: TCP record, %d bytes\n", svc_sock_reclen(svsk));
+               if (svc_sock_reclen(svsk) > serv->sv_max_mesg) {
                        net_notice_ratelimited("RPC: fragment too large: 0x%08lx\n",
-                                              (unsigned long)svsk->sk_reclen);
+                                       (unsigned long)svc_sock_reclen(svsk));
                        goto err_delete;
                }
        }
 
-       if (svsk->sk_reclen < 8)
+       if (svc_sock_reclen(svsk) < 8)
                goto err_delete; /* client is nuts. */
 
-       len = svsk->sk_reclen;
-
-       return len;
+       return svc_sock_reclen(svsk);
 error:
        dprintk("RPC: TCP recv_record got %d\n", len);
        return len;
@@ -1019,7 +1015,7 @@ static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
        if (dst->iov_len < src->iov_len)
                return -EAGAIN; /* whatever; just giving up. */
        memcpy(dst->iov_base, src->iov_base, src->iov_len);
-       xprt_complete_rqst(req->rq_task, svsk->sk_reclen);
+       xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
        rqstp->rq_arg.len = 0;
        return 0;
 }
@@ -1064,12 +1060,12 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
                goto error;
 
        base = svc_tcp_restore_pages(svsk, rqstp);
-       want = svsk->sk_reclen - base;
+       want = svc_sock_reclen(svsk) - base;
 
        vec = rqstp->rq_vec;
 
        pnum = copy_pages_to_kvecs(&vec[0], &rqstp->rq_pages[0],
-                                               svsk->sk_reclen);
+                                               svc_sock_reclen(svsk));
 
        rqstp->rq_respages = &rqstp->rq_pages[pnum];
 
@@ -1082,11 +1078,11 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
                if (len < 0 && len != -EAGAIN)
                        goto err_other;
                dprintk("svc: incomplete TCP record (%d of %d)\n",
-                       svsk->sk_tcplen, svsk->sk_reclen);
+                       svsk->sk_tcplen, svc_sock_reclen(svsk));
                goto err_noclose;
        }
 
-       rqstp->rq_arg.len = svsk->sk_reclen;
+       rqstp->rq_arg.len = svc_sock_reclen(svsk);
        rqstp->rq_arg.page_base = 0;
        if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
                rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;