Merge branch 'work.sock_recvmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull kern_recvmsg reduction from Al Viro:
 "kernel_recvmsg() is a set_fs()-using wrapper for sock_recvmsg(). In
  all but one case that is not needed - use of ITER_KVEC for ->msg_iter
  takes care of the data and does not care about set_fs(). The only
  exception is svc_udp_recvfrom() where we want cmsg to be store into
  kernel object; everything else can just use sock_recvmsg() and be done
  with that.

  A followup converting svc_udp_recvfrom() away from set_fs() (and
  killing kernel_recvmsg() off) is *NOT* in here - I'd like to hear what
  netdev folks think of the approach proposed in that followup)"

* 'work.sock_recvmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  tipc: switch to sock_recvmsg()
  smc: switch to sock_recvmsg()
  ipvs: switch to sock_recvmsg()
  mISDN: switch to sock_recvmsg()
  drbd: switch to sock_recvmsg()
  lustre lnet_sock_read(): switch to sock_recvmsg()
  cfs2: switch to sock_recvmsg()
  ncpfs: switch to sock_recvmsg()
  dlm: switch to sock_recvmsg()
  svc_recvfrom(): switch to sock_recvmsg()

11 files changed, 46 insertions, 56 deletions

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 4b4697a1f963..0a0394aa1b9c 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1847,7 +1847,7 @@ int drbd_send(struct drbd_connection *connection, struct socket *sock,
               void *buf, size_t size, unsigned msg_flags)
 {
         struct kvec iov = {.iov_base = buf, .iov_len = size};
-        struct msghdr msg;
+        struct msghdr msg = {.msg_flags = msg_flags | MSG_NOSIGNAL};
         int rv, sent = 0;
 
         if (!sock)
@@ -1855,12 +1855,6 @@ int drbd_send(struct drbd_connection *connection, struct socket *sock,
 
         /* THINK  if (signal_pending) return ... ? */
 
-        msg.msg_name       = NULL;
-        msg.msg_namelen    = 0;
-        msg.msg_control    = NULL;
-        msg.msg_controllen = 0;
-        msg.msg_flags      = msg_flags | MSG_NOSIGNAL;
-
         iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iov, 1, size);
 
         if (sock == connection->data.socket) {
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index cb2fa63f6bc0..c72dee0ef083 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -516,7 +516,8 @@ static int drbd_recv_short(struct socket *sock, void *buf, size_t size, int flag
         struct msghdr msg = {
                 .msg_flags = (flags ? flags : MSG_WAITALL | MSG_NOSIGNAL)
         };
-        return kernel_recvmsg(sock, &msg, &iov, 1, size, msg.msg_flags);
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, size);
+        return sock_recvmsg(sock, &msg, msg.msg_flags);
 }
 
 static int drbd_recv(struct drbd_connection *connection, void *buf, size_t size)
diff --git a/drivers/isdn/mISDN/l1oip_core.c b/drivers/isdn/mISDN/l1oip_core.c
index e3654782a3e2..21d50e4cc5e1 100644
--- a/drivers/isdn/mISDN/l1oip_core.c
+++ b/drivers/isdn/mISDN/l1oip_core.c
@@ -645,8 +645,10 @@ l1oip_socket_thread(void *data)
 {
         struct l1oip *hc = (struct l1oip *)data;
         int ret = 0;
-        struct msghdr msg;
         struct sockaddr_in sin_rx;
+        struct kvec iov;
+        struct msghdr msg = {.msg_name = &sin_rx,
+                             .msg_namelen = sizeof(sin_rx)};
         unsigned char *recvbuf;
         size_t recvbuf_size = 1500;
         int recvlen;
@@ -661,6 +663,9 @@ l1oip_socket_thread(void *data)
                 goto fail;
         }
 
+        iov.iov_base = recvbuf;
+        iov.iov_len = recvbuf_size;
+
         /* make daemon */
         allow_signal(SIGTERM);
 
@@ -697,12 +702,6 @@ l1oip_socket_thread(void *data)
                 goto fail;
         }
 
-        /* build receive message */
-        msg.msg_name = &sin_rx;
-        msg.msg_namelen = sizeof(sin_rx);
-        msg.msg_control = NULL;
-        msg.msg_controllen = 0;
-
         /* build send message */
         hc->sendmsg.msg_name = &hc->sin_remote;
         hc->sendmsg.msg_namelen = sizeof(hc->sin_remote);
@@ -719,12 +718,9 @@ l1oip_socket_thread(void *data)
                 printk(KERN_DEBUG "%s: socket created and open\n",
                        __func__);
         while (!signal_pending(current)) {
-                struct kvec iov = {
-                        .iov_base = recvbuf,
-                        .iov_len = recvbuf_size,
-                };
-                recvlen = kernel_recvmsg(socket, &msg, &iov, 1,
-                                         recvbuf_size, 0);
+                iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1,
+                                recvbuf_size);
+                recvlen = sock_recvmsg(socket, &msg, 0);
                 if (recvlen > 0) {
                         l1oip_socket_parse(hc, &sin_rx, recvbuf, recvlen);
                 } else {
diff --git a/drivers/staging/lustre/lnet/lnet/lib-socket.c b/drivers/staging/lustre/lnet/lnet/lib-socket.c
index 7d49d4865298..ed46aaca0ba3 100644
--- a/drivers/staging/lustre/lnet/lnet/lib-socket.c
+++ b/drivers/staging/lustre/lnet/lnet/lib-socket.c
@@ -314,19 +314,20 @@ lnet_sock_read(struct socket *sock, void *buffer, int nob, int timeout)
         long jiffies_left = timeout * msecs_to_jiffies(MSEC_PER_SEC);
         unsigned long then;
         struct timeval tv;
+        struct kvec  iov = {
+                .iov_base = buffer,
+                .iov_len  = nob
+        };
+        struct msghdr msg = {
+                .msg_flags = 0
+        };
 
         LASSERT(nob > 0);
         LASSERT(jiffies_left > 0);
 
-        for (;;) {
-                struct kvec  iov = {
-                        .iov_base = buffer,
-                        .iov_len  = nob
-                };
-                struct msghdr msg = {
-                        .msg_flags = 0
-                };
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, nob);
 
+        for (;;) {
                 /* Set receive timeout to remaining time */
                 jiffies_to_timeval(jiffies_left, &tv);
                 rc = kernel_setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
@@ -338,7 +339,7 @@ lnet_sock_read(struct socket *sock, void *buffer, int nob, int timeout)
                 }
 
                 then = jiffies;
-                rc = kernel_recvmsg(sock, &msg, &iov, 1, nob, 0);
+                rc = sock_recvmsg(sock, &msg, 0);
                 jiffies_left -= jiffies - then;
 
                 if (rc < 0)
@@ -347,10 +348,7 @@ lnet_sock_read(struct socket *sock, void *buffer, int nob, int timeout)
                 if (!rc)
                         return -ECONNRESET;
 
-                buffer = ((char *)buffer) + rc;
-                nob -= rc;
-
-                if (!nob)
+                if (!msg_data_left(&msg))
                         return 0;
 
                 if (jiffies_left <= 0)
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 05707850f93a..cff79ea0c01d 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -675,9 +675,9 @@ static int receive_from_sock(struct connection *con)
                 nvec = 2;
         }
         len = iov[0].iov_len + iov[1].iov_len;
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, iov, nvec, len);
 
-        r = ret = kernel_recvmsg(con->sock, &msg, iov, nvec, len,
-                               MSG_DONTWAIT | MSG_NOSIGNAL);
+        r = ret = sock_recvmsg(con->sock, &msg, MSG_DONTWAIT | MSG_NOSIGNAL);
         if (ret <= 0)
                 goto out_close;
         else if (ret == len)
diff --git a/fs/ncpfs/sock.c b/fs/ncpfs/sock.c
index efb176b1751a..4c13174d85b7 100644
--- a/fs/ncpfs/sock.c
+++ b/fs/ncpfs/sock.c
@@ -39,7 +39,8 @@ static int _recv(struct socket *sock, void *buf, int size, unsigned flags)
 {
         struct msghdr msg = {NULL, };
         struct kvec iov = {buf, size};
-        return kernel_recvmsg(sock, &msg, &iov, 1, size, flags);
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, size);
+        return sock_recvmsg(sock, &msg, flags);
 }
 
 static int _send(struct socket *sock, const void *buff, int len)
diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index bebe59feca58..eac5140aac47 100644
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c
@@ -918,7 +918,8 @@ static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len)
 {
         struct kvec vec = { .iov_len = len, .iov_base = data, };
         struct msghdr msg = { .msg_flags = MSG_DONTWAIT, };
-        return kernel_recvmsg(sock, &msg, &vec, 1, len, msg.msg_flags);
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1, len);
+        return sock_recvmsg(sock, &msg, MSG_DONTWAIT);
 }
 
 static int o2net_send_tcp_msg(struct socket *sock, struct kvec *vec,
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index 9ee71cb276d7..fbaf3bd05b2e 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -1636,17 +1636,14 @@ static int
 ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
 {
         struct msghdr           msg = {NULL,};
-        struct kvec             iov;
+        struct kvec             iov = {buffer, buflen};
         int                     len;
 
         EnterFunction(7);
 
         /* Receive a packet */
-        iov.iov_base     = buffer;
-        iov.iov_len      = (size_t)buflen;
-
-        len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, MSG_DONTWAIT);
-
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, buflen);
+        len = sock_recvmsg(sock, &msg, MSG_DONTWAIT);
         if (len < 0)
                 return len;
 
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 1800e16b2a02..511548085d16 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -35,7 +35,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
         struct smc_clc_msg_hdr *clcm = buf;
         struct msghdr msg = {NULL, 0};
         int reason_code = 0;
-        struct kvec vec;
+        struct kvec vec = {buf, buflen};
         int len, datlen;
         int krflags;
 
@@ -43,12 +43,15 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
          * so we don't consume any subsequent CLC message or payload data
          * in the TCP byte stream
          */
-        vec.iov_base = buf;
-        vec.iov_len = buflen;
+        /*
+         * Caller must make sure that buflen is no less than
+         * sizeof(struct smc_clc_msg_hdr)
+         */
         krflags = MSG_PEEK | MSG_WAITALL;
         smc->clcsock->sk->sk_rcvtimeo = CLC_WAIT_TIME;
-        len = kernel_recvmsg(smc->clcsock, &msg, &vec, 1,
-                             sizeof(struct smc_clc_msg_hdr), krflags);
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1,
+                        sizeof(struct smc_clc_msg_hdr));
+        len = sock_recvmsg(smc->clcsock, &msg, krflags);
         if (signal_pending(current)) {
                 reason_code = -EINTR;
                 clc_sk->sk_err = EINTR;
@@ -83,12 +86,11 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
         }
 
         /* receive the complete CLC message */
-        vec.iov_base = buf;
-        vec.iov_len = buflen;
         memset(&msg, 0, sizeof(struct msghdr));
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1, buflen);
         krflags = MSG_WAITALL;
         smc->clcsock->sk->sk_rcvtimeo = CLC_WAIT_TIME;
-        len = kernel_recvmsg(smc->clcsock, &msg, &vec, 1, datlen, krflags);
+        len = sock_recvmsg(smc->clcsock, &msg, krflags);
         if (len < datlen) {
                 smc->sk.sk_err = EPROTO;
                 reason_code = -EPROTO;
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index ff8e06cd067e..5570719e4787 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -338,8 +338,8 @@ static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr,
         rqstp->rq_xprt_hlen = 0;
 
         clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
-        len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen,
-                                msg.msg_flags);
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, iov, nr, buflen);
+        len = sock_recvmsg(svsk->sk_sock, &msg, msg.msg_flags);
         /* If we read a full record, then assume there may be more
          * data to read (stream based sockets only!)
          */
diff --git a/net/tipc/server.c b/net/tipc/server.c
index d60c30342327..78a292a84afc 100644
--- a/net/tipc/server.c
+++ b/net/tipc/server.c
@@ -264,8 +264,8 @@ static int tipc_receive_from_sock(struct tipc_conn *con)
         iov.iov_base = buf;
         iov.iov_len = s->max_rcvbuf_size;
         msg.msg_name = &addr;
-        ret = kernel_recvmsg(con->sock, &msg, &iov, 1, iov.iov_len,
-                             MSG_DONTWAIT);
+        iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, iov.iov_len);
+        ret = sock_recvmsg(con->sock, &msg, MSG_DONTWAIT);
         if (ret <= 0) {
                 kmem_cache_free(s->rcvbuf_cache, buf);
                 goto out_close;