Phonet: receive pipe control requests as out-of-band data
Rémi Denis-Courmont [Sun, 5 Oct 2008 18:15:43 +0000 (11:15 -0700)]
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/phonet/pep.h
net/phonet/pep.c
net/phonet/socket.c

index fb024e1..4d79564 100644 (file)
@@ -33,6 +33,8 @@ struct pep_sock {
 
        /* Connected socket stuff: */
        struct sock             *listener;
+       struct sk_buff_head     ctrlreq_queue;
+#define PNPIPE_CTRLREQ_MAX     10
        u16                     peer_type;      /* peer type/subtype */
        u8                      pipe_handle;
 
index c5dfecb..d564d07 100644 (file)
@@ -137,14 +137,15 @@ static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code)
 
 /* Control requests are not sent by the pipe service and have a specific
  * message format. */
-static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code)
+static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code,
+                               gfp_t priority)
 {
        const struct pnpipehdr *oph = pnp_hdr(oskb);
        struct sk_buff *skb;
        struct pnpipehdr *ph;
        struct sockaddr_pn dst;
 
-       skb = alloc_skb(MAX_PNPIPE_HEADER + 4, GFP_ATOMIC);
+       skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority);
        if (!skb)
                return -ENOMEM;
        skb_set_owner_w(skb, sk);
@@ -305,6 +306,7 @@ static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
 {
        struct pep_sock *pn = pep_sk(sk);
        struct pnpipehdr *hdr = pnp_hdr(skb);
+       struct sk_buff_head *queue;
        int err = 0;
 
        BUG_ON(sk->sk_state == TCP_CLOSE_WAIT);
@@ -345,9 +347,11 @@ static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
                break;
 
        case PNS_PEP_CTRL_REQ:
-               /* TODO */
-               pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR);
-               break;
+               if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX)
+                       break;
+               __skb_pull(skb, 4);
+               queue = &pn->ctrlreq_queue;
+               goto queue;
 
        case PNS_PIPE_DATA:
                __skb_pull(skb, 3); /* Pipe data header */
@@ -363,13 +367,8 @@ static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
                        break;
                }
                pn->rx_credits--;
-               skb->dev = NULL;
-               skb_set_owner_r(skb, sk);
-               err = skb->len;
-               skb_queue_tail(&sk->sk_receive_queue, skb);
-               if (!sock_flag(sk, SOCK_DEAD))
-                       sk->sk_data_ready(sk, err);
-               return 0;
+               queue = &sk->sk_receive_queue;
+               goto queue;
 
        case PNS_PEP_STATUS_IND:
                pipe_rcv_status(sk, skb);
@@ -412,12 +411,24 @@ static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb)
 out:
        kfree_skb(skb);
        return err;
+
+queue:
+       skb->dev = NULL;
+       skb_set_owner_r(skb, sk);
+       err = skb->len;
+       skb_queue_tail(queue, skb);
+       if (!sock_flag(sk, SOCK_DEAD))
+               sk->sk_data_ready(sk, err);
+       return 0;
 }
 
 /* Destroy connected sock. */
 static void pipe_destruct(struct sock *sk)
 {
+       struct pep_sock *pn = pep_sk(sk);
+
        skb_queue_purge(&sk->sk_receive_queue);
+       skb_queue_purge(&pn->ctrlreq_queue);
 }
 
 static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb)
@@ -490,6 +501,7 @@ static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb)
        pn_skb_get_dst_sockaddr(skb, &dst);
        newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst);
        newpn->pn_sk.resource = pn->pn_sk.resource;
+       skb_queue_head_init(&newpn->ctrlreq_queue);
        newpn->pipe_handle = pipe_handle;
        newpn->peer_type = peer_type;
        newpn->rx_credits = newpn->tx_credits = 0;
@@ -581,7 +593,7 @@ static int pep_do_rcv(struct sock *sk, struct sk_buff *skb)
                break;
 
        case PNS_PEP_CTRL_REQ:
-               pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE);
+               pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE, GFP_ATOMIC);
                break;
 
        case PNS_PEP_RESET_REQ:
@@ -684,6 +696,7 @@ out:
 
 static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
 {
+       struct pep_sock *pn = pep_sk(sk);
        int answ;
 
        switch (cmd) {
@@ -692,7 +705,10 @@ static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg)
                        return -EINVAL;
 
                lock_sock(sk);
-               if (!skb_queue_empty(&sk->sk_receive_queue))
+               if (sock_flag(sk, SOCK_URGINLINE)
+                && !skb_queue_empty(&pn->ctrlreq_queue))
+                       answ = skb_peek(&pn->ctrlreq_queue)->len;
+               else if (!skb_queue_empty(&sk->sk_receive_queue))
                        answ = skb_peek(&sk->sk_receive_queue)->len;
                else
                        answ = 0;
@@ -709,6 +725,7 @@ static int pep_init(struct sock *sk)
 
        INIT_HLIST_HEAD(&pn->ackq);
        INIT_HLIST_HEAD(&pn->hlist);
+       skb_queue_head_init(&pn->ctrlreq_queue);
        pn->pipe_handle = PN_PIPE_INVALID_HANDLE;
        return 0;
 }
@@ -810,11 +827,24 @@ static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
        struct sk_buff *skb;
        int err;
 
-       if (unlikely(flags & MSG_OOB))
-               return -EOPNOTSUPP;
        if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
                return -ENOTCONN;
 
+       if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
+               /* Dequeue and acknowledge control request */
+               struct pep_sock *pn = pep_sk(sk);
+
+               skb = skb_dequeue(&pn->ctrlreq_queue);
+               if (skb) {
+                       pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
+                                               GFP_KERNEL);
+                       msg->msg_flags |= MSG_OOB;
+                       goto copy;
+               }
+               if (flags & MSG_OOB)
+                       return -EINVAL;
+       }
+
        skb = skb_recv_datagram(sk, flags, noblock, &err);
        lock_sock(sk);
        if (skb == NULL) {
@@ -827,9 +857,8 @@ static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
        if (sk->sk_state == TCP_ESTABLISHED)
                pipe_grant_credits(sk);
        release_sock(sk);
-
+copy:
        msg->msg_flags |= MSG_EOR;
-
        if (skb->len > len)
                msg->msg_flags |= MSG_TRUNC;
        else
index cea1136..a9c3d1f 100644 (file)
@@ -220,7 +220,9 @@ static unsigned int pn_socket_poll(struct file *file, struct socket *sock,
 
        if (!skb_queue_empty(&sk->sk_receive_queue))
                mask |= POLLIN | POLLRDNORM;
-       else if (sk->sk_state == TCP_CLOSE_WAIT)
+       if (!skb_queue_empty(&pn->ctrlreq_queue))
+               mask |= POLLPRI;
+       if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
                return POLLHUP;
 
        if (sk->sk_state == TCP_ESTABLISHED && pn->tx_credits)