diff options
Diffstat (limited to 'net/iucv/af_iucv.c')
| -rw-r--r-- | net/iucv/af_iucv.c | 144 |
1 files changed, 103 insertions, 41 deletions
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c index 42b7198a6883..abadb4a846cf 100644 --- a/net/iucv/af_iucv.c +++ b/net/iucv/af_iucv.c @@ -53,6 +53,38 @@ static const u8 iprm_shutdown[8] = #define CB_TRGCLS(skb) ((skb)->cb + CB_TAG_LEN) /* iucv msg target class */ #define CB_TRGCLS_LEN (TRGCLS_SIZE) +#define __iucv_sock_wait(sk, condition, timeo, ret) \ +do { \ + DEFINE_WAIT(__wait); \ + long __timeo = timeo; \ + ret = 0; \ + while (!(condition)) { \ + prepare_to_wait(sk->sk_sleep, &__wait, TASK_INTERRUPTIBLE); \ + if (!__timeo) { \ + ret = -EAGAIN; \ + break; \ + } \ + if (signal_pending(current)) { \ + ret = sock_intr_errno(__timeo); \ + break; \ + } \ + release_sock(sk); \ + __timeo = schedule_timeout(__timeo); \ + lock_sock(sk); \ + ret = sock_error(sk); \ + if (ret) \ + break; \ + } \ + finish_wait(sk->sk_sleep, &__wait); \ +} while (0) + +#define iucv_sock_wait(sk, condition, timeo) \ +({ \ + int __ret = 0; \ + if (!(condition)) \ + __iucv_sock_wait(sk, condition, timeo, __ret); \ + __ret; \ +}) static void iucv_sock_kill(struct sock *sk); static void iucv_sock_close(struct sock *sk); @@ -121,6 +153,48 @@ static inline size_t iucv_msg_length(struct iucv_message *msg) return msg->length; } +/** + * iucv_sock_in_state() - check for specific states + * @sk: sock structure + * @state: first iucv sk state + * @state: second iucv sk state + * + * Returns true if the socket in either in the first or second state. + */ +static int iucv_sock_in_state(struct sock *sk, int state, int state2) +{ + return (sk->sk_state == state || sk->sk_state == state2); +} + +/** + * iucv_below_msglim() - function to check if messages can be sent + * @sk: sock structure + * + * Returns true if the send queue length is lower than the message limit. + * Always returns true if the socket is not connected (no iucv path for + * checking the message limit). + */ +static inline int iucv_below_msglim(struct sock *sk) +{ + struct iucv_sock *iucv = iucv_sk(sk); + + if (sk->sk_state != IUCV_CONNECTED) + return 1; + return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim); +} + +/** + * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit + */ +static void iucv_sock_wake_msglim(struct sock *sk) +{ + read_lock(&sk->sk_callback_lock); + if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) + wake_up_interruptible_all(sk->sk_sleep); + sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); + read_unlock(&sk->sk_callback_lock); +} + /* Timers */ static void iucv_sock_timeout(unsigned long arg) { @@ -212,7 +286,9 @@ static void iucv_sock_close(struct sock *sk) timeo = sk->sk_lingertime; else timeo = IUCV_DISCONN_TIMEOUT; - err = iucv_sock_wait_state(sk, IUCV_CLOSED, 0, timeo); + err = iucv_sock_wait(sk, + iucv_sock_in_state(sk, IUCV_CLOSED, 0), + timeo); } case IUCV_CLOSING: /* fall through */ @@ -393,39 +469,6 @@ struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock) return NULL; } -int iucv_sock_wait_state(struct sock *sk, int state, int state2, - unsigned long timeo) -{ - DECLARE_WAITQUEUE(wait, current); - int err = 0; - - add_wait_queue(sk->sk_sleep, &wait); - while (sk->sk_state != state && sk->sk_state != state2) { - set_current_state(TASK_INTERRUPTIBLE); - - if (!timeo) { - err = -EAGAIN; - break; - } - - if (signal_pending(current)) { - err = sock_intr_errno(timeo); - break; - } - - release_sock(sk); - timeo = schedule_timeout(timeo); - lock_sock(sk); - - err = sock_error(sk); - if (err) - break; - } - set_current_state(TASK_RUNNING); - remove_wait_queue(sk->sk_sleep, &wait); - return err; -} - /* Bind an unbound socket */ static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len) @@ -570,8 +613,9 @@ static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr, } if (sk->sk_state != IUCV_CONNECTED) { - err = iucv_sock_wait_state(sk, IUCV_CONNECTED, IUCV_DISCONN, - sock_sndtimeo(sk, flags & O_NONBLOCK)); + err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED, + IUCV_DISCONN), + sock_sndtimeo(sk, flags & O_NONBLOCK)); } if (sk->sk_state == IUCV_DISCONN) { @@ -725,9 +769,11 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct iucv_message txmsg; struct cmsghdr *cmsg; int cmsg_done; + long timeo; char user_id[9]; char appl_id[9]; int err; + int noblock = msg->msg_flags & MSG_DONTWAIT; err = sock_error(sk); if (err) @@ -799,8 +845,7 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, * this is fine for SOCK_SEQPACKET (unless we want to support * segmented records using the MSG_EOR flag), but * for SOCK_STREAM we might want to improve it in future */ - skb = sock_alloc_send_skb(sk, len, msg->msg_flags & MSG_DONTWAIT, - &err); + skb = sock_alloc_send_skb(sk, len, noblock, &err); if (!skb) goto out; if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { @@ -808,6 +853,18 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, goto fail; } + /* wait if outstanding messages for iucv path has reached */ + timeo = sock_sndtimeo(sk, noblock); + err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo); + if (err) + goto fail; + + /* return -ECONNRESET if the socket is no longer connected */ + if (sk->sk_state != IUCV_CONNECTED) { + err = -ECONNRESET; + goto fail; + } + /* increment and save iucv message tag for msg_completion cbk */ txmsg.tag = iucv->send_tag++; memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN); @@ -844,9 +901,10 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock, pr_err("Application %s on z/VM guest %s" " exceeds message limit\n", appl_id, user_id); - } + err = -EAGAIN; + } else + err = -EPIPE; skb_unlink(skb, &iucv->send_skb_q); - err = -EPIPE; goto fail; } @@ -1463,7 +1521,11 @@ static void iucv_callback_txdone(struct iucv_path *path, spin_unlock_irqrestore(&list->lock, flags); - kfree_skb(this); + if (this) { + kfree_skb(this); + /* wake up any process waiting for sending */ + iucv_sock_wake_msglim(sk); + } } BUG_ON(!this); |