C++ sock_owned_by_user函数代码示例

static void svc_reclassify_socket(struct socket *sock)
{
	struct sock *sk = sock->sk;

	WARN_ON_ONCE(sock_owned_by_user(sk));
	if (sock_owned_by_user(sk))
		return;

	switch (sk->sk_family) {
	case AF_INET:
		sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD",
					      &svc_slock_key[0],
					      "sk_xprt.xpt_lock-AF_INET-NFSD",
					      &svc_key[0]);
		break;

	case AF_INET6:
		sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD",
					      &svc_slock_key[1],
					      "sk_xprt.xpt_lock-AF_INET6-NFSD",
					      &svc_key[1]);
		break;

	default:
		BUG();
	}
}

static void dn_slow_timer(unsigned long arg)
{
	struct sock *sk = (struct sock *)arg;
	struct dn_scp *scp = DN_SK(sk);

	bh_lock_sock(sk);

	if (sock_owned_by_user(sk)) {
		sk_reset_timer(sk, &sk->sk_timer, jiffies + HZ / 10);
		goto out;
	}

	if (scp->persist && scp->persist_fxn) {
		if (scp->persist <= SLOW_INTERVAL) {
			scp->persist = 0;

			if (scp->persist_fxn(sk))
				goto out;
		} else {
			scp->persist -= SLOW_INTERVAL;
		}
	}

	if (scp->keepalive && scp->keepalive_fxn && (scp->state == DN_RUN)) {
		if ((jiffies - scp->stamp) >= scp->keepalive)
			scp->keepalive_fxn(sk);
	}

	sk_reset_timer(sk, &sk->sk_timer, jiffies + SLOW_INTERVAL);
out:
	bh_unlock_sock(sk);
	sock_put(sk);
}

static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf)
{
	struct sock *sk = (struct sock *)tport->usr_handle;
	u32 res;

	/*
	 * Process message if socket is unlocked; otherwise add to backlog queue
	 *
	 * This code is based on sk_receive_skb(), but must be distinct from it
	 * since a TIPC-specific filter/reject mechanism is utilized
	 */

	bh_lock_sock(sk);
	if (!sock_owned_by_user(sk)) {
		res = filter_rcv(sk, buf);
	} else {
		if (sk_add_backlog(sk, buf))
			res = TIPC_ERR_OVERLOAD;
		else
			res = TIPC_OK;
	}
	bh_unlock_sock(sk);

	return res;
}

struct sk_filter *
pfq_alloc_sk_filter(struct sock_fprog *fprog)
{
	struct sock sk;
	int rv;

	sock_init_data(NULL, &sk);
	sk.sk_filter = NULL;
	atomic_set(&sk.sk_omem_alloc, 0);
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,9,0))
	sock_reset_flag(&sk, SOCK_FILTER_LOCKED);
#endif
        pr_devel("[PFQ] BPF: new fprog (len %d)\n", fprog->len);

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,4,8) && LINUX_VERSION_CODE < KERNEL_VERSION(4,7,0))
	if ((rv = __sk_attach_filter(fprog, &sk, sock_owned_by_user(&sk))))
#else
	if ((rv = sk_attach_filter(fprog, &sk)))
#endif
	{
		pr_devel("[PFQ] BPF: sk_attach_filter error: (%d)!\n", rv);
		return NULL;
	}

	return sk.sk_filter;
}

/**
 *	sk_attach_filter - attach a socket filter
 *	@fprog: the filter program
 *	@sk: the socket to use
 *
 * Attach the user's filter code. We first run some sanity checks on
 * it to make sure it does not explode on us later. If an error
 * occurs or there is insufficient memory for the filter a negative
 * errno code is returned. On success the return is zero.
 */
int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
	struct sk_filter *fp, *old_fp;
	unsigned int fsize = sizeof(struct sock_filter) * fprog->len;
	int err;

	/* Make sure new filter is there and in the right amounts. */
	if (fprog->filter == NULL)
		return -EINVAL;

	fp = sock_kmalloc(sk, fsize+sizeof(*fp), GFP_KERNEL);
	if (!fp)
		return -ENOMEM;
	if (copy_from_user(fp->insns, fprog->filter, fsize)) {
		sock_kfree_s(sk, fp, fsize+sizeof(*fp));
		return -EFAULT;
	}

	atomic_set(&fp->refcnt, 1);
	fp->len = fprog->len;

	err = sk_chk_filter(fp->insns, fp->len);
	if (err) {
		sk_filter_uncharge(sk, fp);
		return err;
	}

	old_fp = rcu_dereference_protected(sk->sk_filter,
					   sock_owned_by_user(sk));
	rcu_assign_pointer(sk->sk_filter, fp);

	if (old_fp)
		sk_filter_uncharge(sk, old_fp);
	return 0;
}

static void dn_slow_timer(unsigned long arg)
{
	struct sock *sk = (struct sock *)arg;
	struct dn_scp *scp = DN_SK(sk);

	sock_hold(sk);
	bh_lock_sock(sk);

	if (sock_owned_by_user(sk)) {
		sk->sk_timer.expires = jiffies + HZ / 10;
		add_timer(&sk->sk_timer);
		goto out;
	}

	/*
	 * The persist timer is the standard slow timer used for retransmits
	 * in both connection establishment and disconnection as well as
	 * in the RUN state. The different states are catered for by changing
	 * the function pointer in the socket. Setting the timer to a value
	 * of zero turns it off. We allow the persist_fxn to turn the
	 * timer off in a permant way by returning non-zero, so that
	 * timer based routines may remove sockets. This is why we have a
	 * sock_hold()/sock_put() around the timer to prevent the socket
	 * going away in the middle.
	 */
	if (scp->persist && scp->persist_fxn) {
		if (scp->persist <= SLOW_INTERVAL) {
			scp->persist = 0;

			if (scp->persist_fxn(sk))
				goto out;
		} else {
			scp->persist -= SLOW_INTERVAL;
		}
	}

	/*
	 * Check for keepalive timeout. After the other timer 'cos if
	 * the previous timer caused a retransmit, we don't need to
	 * do this. scp->stamp is the last time that we sent a packet.
	 * The keepalive function sends a link service packet to the
	 * other end. If it remains unacknowledged, the standard
	 * socket timers will eventually shut the socket down. Each
	 * time we do this, scp->stamp will be updated, thus
	 * we won't try and send another until scp->keepalive has passed
	 * since the last successful transmission.
	 */
	if (scp->keepalive && scp->keepalive_fxn && (scp->state == DN_RUN)) {
		if ((jiffies - scp->stamp) >= scp->keepalive)
			scp->keepalive_fxn(sk);
	}

	sk->sk_timer.expires = jiffies + SLOW_INTERVAL;

	add_timer(&sk->sk_timer);
out:
	bh_unlock_sock(sk);
	sock_put(sk);
}

void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb)
{
	struct llc_addr saddr, daddr;
	struct sock *sk;

	llc_pdu_decode_sa(skb, saddr.mac);
	llc_pdu_decode_ssap(skb, &saddr.lsap);
	llc_pdu_decode_da(skb, daddr.mac);
	llc_pdu_decode_dsap(skb, &daddr.lsap);

	sk = __llc_lookup(sap, &saddr, &daddr);
	if (!sk)
		goto drop;

	bh_lock_sock(sk);
	/*
	 * This has to be done here and not at the upper layer ->accept
	 * method because of the way the PROCOM state machine works:
	 * it needs to set several state variables (see, for instance,
	 * llc_adm_actions_2 in net/llc/llc_c_st.c) and send a packet to
	 * the originator of the new connection, and this state has to be
	 * in the newly created struct sock private area. -acme
	 */
	if (unlikely(sk->sk_state == TCP_LISTEN)) {
		struct sock *newsk = llc_create_incoming_sock(sk, skb->dev,
							      &saddr, &daddr);
		if (!newsk)
			goto drop_unlock;
		skb_set_owner_r(skb, newsk);
	} else {
		/*
		 * Can't be skb_set_owner_r, this will be done at the
		 * llc_conn_state_process function, later on, when we will use
		 * skb_queue_rcv_skb to send it to upper layers, this is
		 * another trick required to cope with how the PROCOM state
		 * machine works. -acme
		 */
		skb->sk = sk;
	}
	if (!sock_owned_by_user(sk))
		llc_conn_rcv(sk, skb);
	else {
;
		llc_set_backlog_type(skb, LLC_PACKET);
		if (sk_add_backlog(sk, skb))
			goto drop_unlock;
	}
out:
	bh_unlock_sock(sk);
	sock_put(sk);
	return;
drop:
	kfree_skb(skb);
	return;
drop_unlock:
	kfree_skb(skb);
	goto out;
}

static void sdp_poll_tx_timeout(unsigned long data)
{
	struct sdp_sock *ssk = (struct sdp_sock *)data;
	struct sock *sk = sk_ssk(ssk);
	u32 inflight, wc_processed;

	sdp_prf1(sk_ssk(ssk), NULL, "TX timeout: inflight=%d, head=%d tail=%d",
		(u32) tx_ring_posted(ssk),
		ring_head(ssk->tx_ring), ring_tail(ssk->tx_ring));

	/* Only process if the socket is not in use */
	bh_lock_sock(sk);
	if (sock_owned_by_user(sk)) {
		sdp_prf(sk_ssk(ssk), NULL, "TX comp: socket is busy");

		if (sdp_tx_handler_select(ssk) && sk->sk_state != TCP_CLOSE &&
				likely(ssk->qp_active)) {
			sdp_prf1(sk, NULL, "schedule a timer");
			mod_timer(&ssk->tx_ring.timer, jiffies + SDP_TX_POLL_TIMEOUT);
		}

		SDPSTATS_COUNTER_INC(tx_poll_busy);
		goto out;
	}

	if (unlikely(!ssk->qp || sk->sk_state == TCP_CLOSE)) {
		SDPSTATS_COUNTER_INC(tx_poll_no_op);
		goto out;
	}

	wc_processed = sdp_process_tx_cq(ssk);
	if (!wc_processed)
		SDPSTATS_COUNTER_INC(tx_poll_miss);
	else {
		sdp_post_sends(ssk, GFP_ATOMIC);
		SDPSTATS_COUNTER_INC(tx_poll_hit);
	}

	inflight = (u32) tx_ring_posted(ssk);
	sdp_prf1(sk_ssk(ssk), NULL, "finished tx proccessing. inflight = %d",
			tx_ring_posted(ssk));

	/* If there are still packets in flight and the timer has not already
	 * been scheduled by the Tx routine then schedule it here to guarantee
	 * completion processing of these packets */
	if (inflight && likely(ssk->qp_active))
		mod_timer(&ssk->tx_ring.timer, jiffies + SDP_TX_POLL_TIMEOUT);

out:
	if (ssk->tx_ring.rdma_inflight && ssk->tx_ring.rdma_inflight->busy) {
		sdp_prf1(sk, NULL, "RDMA is inflight - arming irq");
		sdp_arm_tx_cq(sk);
	}

	bh_unlock_sock(sk);
}

/*
 * Set sock sync properties.
 */
int set_tcp_sock_sync_prop(struct bst_set_sock_sync_prop *set_prop)
{
	int err = 0;
	struct sock *sk;
	struct bastet_sock *bsk;
	struct bst_sock_comm_prop *guide = &set_prop->guide;

	sk = get_sock_by_comm_prop(guide);
	if (NULL == sk) {
		BASTET_LOGE("can not find sock by lport: %d, lIp: %pI4, rport: %d, rIp: %pI4",
					guide->local_port, &guide->local_ip,
					guide->remote_port, &guide->remote_ip);
		return -ENOENT;
	}

	if (sk->sk_state == TCP_TIME_WAIT) {
		BASTET_LOGE("sk: %p not expected time wait sock", sk);
		inet_twsk_put(inet_twsk(sk));
		return -EPERM;
	}

	bsk = sk->bastet;
	if (NULL == bsk) {
		BASTET_LOGE("sk: %p not expected bastet null", sk);
		err = -EPERM;
		goto out_put;
	}

	BASTET_LOGI("sk: %p", sk);

	spin_lock_bh(&sk->sk_lock.slock);

	if (NULL != bsk->sync_p) {
		BASTET_LOGE("sk: %p has a pending sock set", sk);
		err = -EPERM;
		goto out_unlock;
	}

	cancel_sock_bastet_timer(sk);

	if (sock_owned_by_user(sk)) {
		err = setup_sock_sync_set_timer(sk, &set_prop->sync_prop);
		goto out_unlock;
	}

	sock_set_internal(sk, &set_prop->sync_prop);

out_unlock:
	spin_unlock_bh(&sk->sk_lock.slock);

	adjust_traffic_flow_by_sock(sk, set_prop->sync_prop.tx, set_prop->sync_prop.rx);

out_put:
	sock_put(sk);
	return err;
}

/*
 * Close sock, when modem bastet fails this sock.
 */
int set_tcp_sock_closed(struct bst_sock_comm_prop *guide)
{
	int err = 0;
	struct sock *sk;
	struct bastet_sock *bsk;

	sk = get_sock_by_comm_prop(guide);
	if (NULL == sk) {
		BASTET_LOGE("can not find sock by lport: %d, lIp: %pI4, rport: %d, rIp: %pI4",
					guide->local_port, &guide->local_ip,
					guide->remote_port, &guide->remote_ip);
		return -ENOENT;
	}

	if (sk->sk_state == TCP_TIME_WAIT) {
		BASTET_LOGE("sk: %p not expected time wait sock", sk);
		inet_twsk_put(inet_twsk(sk));
		return -EPERM;
	}

	bsk = sk->bastet;
	if (NULL == bsk) {
		BASTET_LOGE("sk: %p not expected bastet null", sk);
		err = -EPERM;
		goto out_put;
	}

	BASTET_LOGI("sk: %p", sk);

	spin_lock_bh(&sk->sk_lock.slock);

	if (BST_SOCK_INVALID != bsk->bastet_sock_state
		&& BST_SOCK_UPDATING != bsk->bastet_sock_state) {
		BASTET_LOGE("sk: %p sync_current_state: %d not expected", sk, bsk->bastet_sock_state);
		goto out_unlock;
	}

	cancel_sock_bastet_timer(sk);

	bsk->bastet_sock_state = BST_SOCK_NOT_USED;

	if (sock_owned_by_user(sk)) {
		setup_sock_sync_close_timer(sk);
		goto out_unlock;
	}

	set_sock_close_internal(sk);

out_unlock:
	spin_unlock_bh(&sk->sk_lock.slock);

out_put:
	sock_put(sk);
	return err;
}

static int x25_receive_data(struct sk_buff *skb, struct x25_neigh *nb)
{
	struct sock *sk;
	unsigned short frametype;
	unsigned int lci;

	frametype = skb->data[2];
        lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);

	/*
	 *	LCI of zero is always for us, and its always a link control
	 *	frame.
	 */
	if (lci == 0) {
		x25_link_control(skb, nb, frametype);
		return 0;
	}

	/*
	 *	Find an existing socket.
	 */
	if ((sk = x25_find_socket(lci, nb)) != NULL) {
		int queued = 1;

		skb->h.raw = skb->data;
		bh_lock_sock(sk);
		if (!sock_owned_by_user(sk)) {
			queued = x25_process_rx_frame(sk, skb);
		} else {
			sk_add_backlog(sk, skb);
		}
		bh_unlock_sock(sk);
		return queued;
	}

	/*
	 *	Is is a Call Request ? if so process it.
	 */
	if (frametype == X25_CALL_REQUEST)
		return x25_rx_call_request(skb, nb, lci);

	/*
	 *	Its not a Call Request, nor is it a control frame.
	 *      Let caller throw it away.
	 */
/*
	x25_transmit_clear_request(nb, lci, 0x0D);
*/

	if (frametype != X25_CLEAR_CONFIRMATION)
		printk(KERN_DEBUG "x25_receive_data(): unknown frame type %2x\n",frametype);

	return 0;
}

static void x25_timer_expiry(unsigned long param)
{
	struct sock *sk = (struct sock *)param;

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk)) { /* can currently only occur in state 3 */
		if (x25_sk(sk)->state == X25_STATE_3)
			x25_start_t2timer(sk);
	} else
		x25_do_timer_expiry(sk);
	bh_unlock_sock(sk);
}

int sk_detach_filter(struct sock *sk)
{
	int ret = -ENOENT;
	struct sk_filter *filter;

	filter = rcu_dereference_protected(sk->sk_filter,
					   sock_owned_by_user(sk));
	if (filter) {
		rcu_assign_pointer(sk->sk_filter, NULL);
		sk_filter_uncharge(sk, filter);
		ret = 0;
	}
	return ret;
}

static int x25_receive_data(struct sk_buff *skb, struct x25_neigh *nb)
{
	struct sock *sk;
	unsigned short frametype;
	unsigned int lci;

	if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
		return 0;

	frametype = skb->data[2];
	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);

	if (lci == 0) {
		x25_link_control(skb, nb, frametype);
		return 0;
	}

	if ((sk = x25_find_socket(lci, nb)) != NULL) {
		int queued = 1;

		skb_reset_transport_header(skb);
		bh_lock_sock(sk);
		if (!sock_owned_by_user(sk)) {
			queued = x25_process_rx_frame(sk, skb);
		} else {
			queued = !sk_add_backlog(sk, skb);
		}
		bh_unlock_sock(sk);
		sock_put(sk);
		return queued;
	}

	if (frametype == X25_CALL_REQUEST)
		return x25_rx_call_request(skb, nb, lci);


	if (x25_forward_data(lci, nb, skb)) {
		if (frametype == X25_CLEAR_CONFIRMATION) {
			x25_clear_forward_by_lci(lci);
		}
		kfree_skb(skb);
		return 1;
	}


	if (frametype != X25_CLEAR_CONFIRMATION)
		printk(KERN_DEBUG "x25_receive_data(): unknown frame type %2x\n",frametype);

	return 0;
}

static void ccid2_hc_tx_rto_expire(unsigned long data)
{
	struct sock *sk = (struct sock *)data;
	struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
	long s;

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk)) {
		sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
			       jiffies + HZ / 5);
		goto out;
	}

	ccid2_pr_debug("RTO_EXPIRE\n");

	ccid2_hc_tx_check_sanity(hctx);

	/* back-off timer */
	hctx->ccid2hctx_rto <<= 1;

	s = hctx->ccid2hctx_rto / HZ;
	if (s > 60)
		hctx->ccid2hctx_rto = 60 * HZ;

	ccid2_start_rto_timer(sk);

	/* adjust pipe, cwnd etc */
	hctx->ccid2hctx_pipe = 0;
	hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd >> 1;
	if (hctx->ccid2hctx_ssthresh < 2)
		hctx->ccid2hctx_ssthresh = 2;
	ccid2_change_cwnd(sk, 1);

	/* clear state about stuff we sent */
	hctx->ccid2hctx_seqt	= hctx->ccid2hctx_seqh;
	hctx->ccid2hctx_ssacks	= 0;
	hctx->ccid2hctx_acks	= 0;
	hctx->ccid2hctx_sent	= 0;

	/* clear ack ratio state. */
	hctx->ccid2hctx_arsent	 = 0;
	hctx->ccid2hctx_ackloss  = 0;
	hctx->ccid2hctx_rpseq	 = 0;
	hctx->ccid2hctx_rpdupack = -1;
	ccid2_change_l_ack_ratio(sk, 1);
	ccid2_hc_tx_check_sanity(hctx);
out:
	bh_unlock_sock(sk);
	sock_put(sk);
}