[LLC]: fix llc_ui_recvmsg, making it behave like tcp_recvmsg

In fact it is an exact copy of the parts that makes sense to LLC :-)

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2005-09-22 08:29:08 -03:00
parent d389424e00
commit 8420e1b541
5 changed files with 154 additions and 36 deletions

View file

@ -38,6 +38,7 @@ struct llc_sock {
struct llc_addr laddr; /* lsap/mac pair */
struct llc_addr daddr; /* dsap/mac pair */
struct net_device *dev; /* device to send to remote */
u32 copied_seq; /* head of yet unread data */
u8 retry_count; /* number of retries */
u8 ack_must_be_send;
u8 first_pdu_Ns;

View file

@ -648,53 +648,167 @@ static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags)
* llc_ui_recvmsg - copy received data to the socket user.
* @sock: Socket to copy data from.
* @msg: Various user space related information.
* @size: Size of user buffer.
* @len: Size of user buffer.
* @flags: User specified flags.
*
* Copy received data to the socket user.
* Returns non-negative upon success, negative otherwise.
*/
static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t size, int flags)
struct msghdr *msg, size_t len, int flags)
{
struct sock *sk = sock->sk;
struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name;
struct sk_buff *skb;
const int nonblock = flags & MSG_DONTWAIT;
struct sk_buff *skb = NULL;
struct sock *sk = sock->sk;
struct llc_sock *llc = llc_sk(sk);
size_t copied = 0;
int rc = -ENOMEM;
int noblock = flags & MSG_DONTWAIT;
u32 peek_seq = 0;
u32 *seq;
unsigned long used;
int target; /* Read at least this many bytes */
long timeo;
dprintk("%s: receiving in %02X from %02X\n", __FUNCTION__,
llc_sk(sk)->laddr.lsap, llc_sk(sk)->daddr.lsap);
lock_sock(sk);
if (skb_queue_empty(&sk->sk_receive_queue)) {
rc = llc_wait_data(sk, sock_rcvtimeo(sk, noblock));
if (rc)
goto out;
}
skb = skb_dequeue(&sk->sk_receive_queue);
if (!skb) /* shutdown */
copied = -ENOTCONN;
if (sk->sk_state == TCP_LISTEN)
goto out;
copied = skb->len;
if (copied > size)
copied = size;
rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
if (rc)
goto dgram_free;
if (skb->len > copied) {
skb_pull(skb, copied);
skb_queue_head(&sk->sk_receive_queue, skb);
}
if (uaddr)
memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
msg->msg_namelen = sizeof(*uaddr);
if (!skb->next) {
dgram_free:
kfree_skb(skb);
}
timeo = sock_rcvtimeo(sk, nonblock);
seq = &llc->copied_seq;
if (flags & MSG_PEEK) {
peek_seq = llc->copied_seq;
seq = &peek_seq;
}
target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
copied = 0;
do {
u32 offset;
/*
* We need to check signals first, to get correct SIGURG
* handling. FIXME: Need to check this doesn't impact 1003.1g
* and move it down to the bottom of the loop
*/
if (signal_pending(current)) {
if (copied)
break;
copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
break;
}
/* Next get a buffer. */
skb = skb_peek(&sk->sk_receive_queue);
if (skb) {
offset = *seq;
goto found_ok_skb;
}
/* Well, if we have backlog, try to process it now yet. */
if (copied >= target && !sk->sk_backlog.tail)
break;
if (copied) {
if (sk->sk_err ||
sk->sk_state == TCP_CLOSE ||
(sk->sk_shutdown & RCV_SHUTDOWN) ||
!timeo ||
(flags & MSG_PEEK))
break;
} else {
if (sock_flag(sk, SOCK_DONE))
break;
if (sk->sk_err) {
copied = sock_error(sk);
break;
}
if (sk->sk_shutdown & RCV_SHUTDOWN)
break;
if (sk->sk_state == TCP_CLOSE) {
if (!sock_flag(sk, SOCK_DONE)) {
/*
* This occurs when user tries to read
* from never connected socket.
*/
copied = -ENOTCONN;
break;
}
break;
}
if (!timeo) {
copied = -EAGAIN;
break;
}
}
if (copied >= target) { /* Do not sleep, just process backlog. */
release_sock(sk);
lock_sock(sk);
} else
sk_wait_data(sk, &timeo);
if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
if (net_ratelimit())
printk(KERN_DEBUG "LLC(%s:%d): Application "
"bug, race in MSG_PEEK.\n",
current->comm, current->pid);
peek_seq = llc->copied_seq;
}
continue;
found_ok_skb:
/* Ok so how much can we use? */
used = skb->len - offset;
if (len < used)
used = len;
if (!(flags & MSG_TRUNC)) {
int rc = skb_copy_datagram_iovec(skb, offset,
msg->msg_iov, used);
if (rc) {
/* Exception. Bailout! */
if (!copied)
copied = -EFAULT;
break;
}
}
*seq += used;
copied += used;
len -= used;
if (used + offset < skb->len)
continue;
if (!(flags & MSG_PEEK)) {
sk_eat_skb(sk, skb);
*seq = 0;
}
} while (len > 0);
/*
* According to UNIX98, msg_name/msg_namelen are ignored
* on connected socket. -ANK
* But... af_llc still doesn't have separate sets of methods for
* SOCK_DGRAM and SOCK_STREAM :-( So we have to do this test, will
* eventually fix this tho :-) -acme
*/
if (sk->sk_type == SOCK_DGRAM)
goto copy_uaddr;
out:
release_sock(sk);
return rc ? : copied;
return copied;
copy_uaddr:
if (uaddr != NULL && skb != NULL) {
memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
msg->msg_namelen = sizeof(*uaddr);
}
goto out;
}
/**

View file

@ -120,8 +120,8 @@ int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
if (!sock_flag(sk, SOCK_DEAD)) {
sk->sk_state_change(sk);
sock_set_flag(sk, SOCK_DEAD);
sk->sk_state_change(sk);
}
}
kfree_skb(skb);

View file

@ -134,7 +134,7 @@ static int llc_seq_socket_show(struct seq_file *seq, void *v)
llc_ui_format_mac(seq, llc->daddr.mac);
seq_printf(seq, "@%02X %8d %8d %2d %3d %4d\n", llc->daddr.lsap,
atomic_read(&sk->sk_wmem_alloc),
atomic_read(&sk->sk_rmem_alloc),
atomic_read(&sk->sk_rmem_alloc) - llc->copied_seq,
sk->sk_state,
sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : -1,
llc->link);

View file

@ -49,9 +49,12 @@ struct sk_buff *llc_alloc_frame(struct sock *sk, struct net_device *dev)
void llc_save_primitive(struct sock *sk, struct sk_buff* skb, u8 prim)
{
struct sockaddr_llc *addr = llc_ui_skb_cb(skb);
struct sockaddr_llc *addr;
if (skb->sk->sk_type == SOCK_STREAM) /* See UNIX98 */
return;
/* save primitive for use by the user. */
addr = llc_ui_skb_cb(skb);
addr->sllc_family = sk->sk_family;
addr->sllc_arphrd = skb->dev->type;
addr->sllc_test = prim == LLC_TEST_PRIM;