Merge branch 'tipc-next'

Jon Maloy says:

====================
tipc: new unicast transmission code

As a step towards making the data transmission code more maintainable
and performant, we introduce a number of new functions, both for
building, sending and rejecting messages. The new functions will
eventually be used for alla data transmission, user data unicast,
service internal messaging, and multicast/broadcast.

We start with this series, where we introduce the functions, and
let user data unicast and the internal connection protocol use them.
The remaining users will come in a later series.

There are only minor changes to data structures, and no protocol
changes, so the older functions can still be used in parallel for
some time. Until the old functions are removed, we use temporary
names for the new functions, such as tipc_build_msg2, tipc_link_xmit2.

It should be noted that the first two commits are unrelated to the
rest of the series.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 158 insertions, 259 deletions

diff --git a/net/tipc/link.c b/net/tipc/link.c
index ad2c57f5868d..a081e7d08d22 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -82,9 +82,6 @@ static void tipc_link_proto_rcv(struct tipc_link *l_ptr, struct sk_buff *buf);
 static int  tipc_link_tunnel_rcv(struct tipc_node *n_ptr,
 				 struct sk_buff **buf);
 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
-static int  tipc_link_iovec_long_xmit(struct tipc_port *sender,
-				      struct iovec const *msg_sect,
-				      unsigned int len, u32 destnode);
 static void link_state_event(struct tipc_link *l_ptr, u32 event);
 static void link_reset_statistics(struct tipc_link *l_ptr);
 static void link_print(struct tipc_link *l_ptr, const char *str);
@@ -335,13 +332,15 @@ void tipc_link_delete_list(unsigned int bearer_id, bool shutting_down)
 static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz)
 {
 	struct tipc_port *p_ptr;
+	struct tipc_sock *tsk;
 
 	spin_lock_bh(&tipc_port_list_lock);
 	p_ptr = tipc_port_lock(origport);
 	if (p_ptr) {
 		if (!list_empty(&p_ptr->wait_list))
 			goto exit;
-		p_ptr->congested = 1;
+		tsk = tipc_port_to_sock(p_ptr);
+		tsk->link_cong = 1;
 		p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
 		list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
 		l_ptr->stats.link_congs++;
@@ -355,6 +354,7 @@ exit:
 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
 {
 	struct tipc_port *p_ptr;
+	struct tipc_sock *tsk;
 	struct tipc_port *temp_p_ptr;
 	int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
 
@@ -370,10 +370,11 @@ void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
 				 wait_list) {
 		if (win <= 0)
 			break;
+		tsk = tipc_port_to_sock(p_ptr);
 		list_del_init(&p_ptr->wait_list);
 		spin_lock_bh(p_ptr->lock);
-		p_ptr->congested = 0;
-		tipc_port_wakeup(p_ptr);
+		tsk->link_cong = 0;
+		tipc_sock_wakeup(tsk);
 		win -= p_ptr->waiting_pkts;
 		spin_unlock_bh(p_ptr->lock);
 	}
@@ -850,6 +851,144 @@ int tipc_link_xmit(struct sk_buff *buf, u32 dest, u32 selector)
 	return res;
 }
 
+/* tipc_link_cong: determine return value and how to treat the
+ * sent buffer during link congestion.
+ * - For plain, errorless user data messages we keep the buffer and
+ *   return -ELINKONG.
+ * - For all other messages we discard the buffer and return -EHOSTUNREACH
+ * - For TIPC internal messages we also reset the link
+ */
+static int tipc_link_cong(struct tipc_link *link, struct sk_buff *buf)
+{
+	struct tipc_msg *msg = buf_msg(buf);
+	uint psz = msg_size(msg);
+	uint imp = tipc_msg_tot_importance(msg);
+	u32 oport = msg_tot_origport(msg);
+
+	if (likely(imp <= TIPC_CRITICAL_IMPORTANCE)) {
+		if (!msg_errcode(msg) && !msg_reroute_cnt(msg)) {
+			link_schedule_port(link, oport, psz);
+			return -ELINKCONG;
+		}
+	} else {
+		pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
+		tipc_link_reset(link);
+	}
+	kfree_skb_list(buf);
+	return -EHOSTUNREACH;
+}
+
+/**
+ * __tipc_link_xmit2(): same as tipc_link_xmit2, but destlink is known & locked
+ * @link: link to use
+ * @buf: chain of buffers containing message
+ * Consumes the buffer chain, except when returning -ELINKCONG
+ * Returns 0 if success, otherwise errno: -ELINKCONG, -EMSGSIZE (plain socket
+ * user data messages) or -EHOSTUNREACH (all other messages/senders)
+ * Only the socket functions tipc_send_stream() and tipc_send_packet() need
+ * to act on the return value, since they may need to do more send attempts.
+ */
+int __tipc_link_xmit2(struct tipc_link *link, struct sk_buff *buf)
+{
+	struct tipc_msg *msg = buf_msg(buf);
+	uint psz = msg_size(msg);
+	uint qsz = link->out_queue_size;
+	uint sndlim = link->queue_limit[0];
+	uint imp = tipc_msg_tot_importance(msg);
+	uint mtu = link->max_pkt;
+	uint ack = mod(link->next_in_no - 1);
+	uint seqno = link->next_out_no;
+	uint bc_last_in = link->owner->bclink.last_in;
+	struct tipc_media_addr *addr = &link->media_addr;
+	struct sk_buff *next = buf->next;
+
+	/* Match queue limits against msg importance: */
+	if (unlikely(qsz >= link->queue_limit[imp]))
+		return tipc_link_cong(link, buf);
+
+	/* Has valid packet limit been used ? */
+	if (unlikely(psz > mtu)) {
+		kfree_skb_list(buf);
+		return -EMSGSIZE;
+	}
+
+	/* Prepare each packet for sending, and add to outqueue: */
+	while (buf) {
+		next = buf->next;
+		msg = buf_msg(buf);
+		msg_set_word(msg, 2, ((ack << 16) | mod(seqno)));
+		msg_set_bcast_ack(msg, bc_last_in);
+
+		if (!link->first_out) {
+			link->first_out = buf;
+		} else if (qsz < sndlim) {
+			link->last_out->next = buf;
+		} else if (tipc_msg_bundle(link->last_out, buf, mtu)) {
+			link->stats.sent_bundled++;
+			buf = next;
+			next = buf->next;
+			continue;
+		} else if (tipc_msg_make_bundle(&buf, mtu, link->addr)) {
+			link->stats.sent_bundled++;
+			link->stats.sent_bundles++;
+			link->last_out->next = buf;
+			if (!link->next_out)
+				link->next_out = buf;
+		} else {
+			link->last_out->next = buf;
+			if (!link->next_out)
+				link->next_out = buf;
+		}
+
+		/* Send packet if possible: */
+		if (likely(++qsz <= sndlim)) {
+			tipc_bearer_send(link->bearer_id, buf, addr);
+			link->next_out = next;
+			link->unacked_window = 0;
+		}
+		seqno++;
+		link->last_out = buf;
+		buf = next;
+	}
+	link->next_out_no = seqno;
+	link->out_queue_size = qsz;
+	return 0;
+}
+
+/**
+ * tipc_link_xmit2() is the general link level function for message sending
+ * @buf: chain of buffers containing message
+ * @dsz: amount of user data to be sent
+ * @dnode: address of destination node
+ * @selector: a number used for deterministic link selection
+ * Consumes the buffer chain, except when returning -ELINKCONG
+ * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
+ */
+int tipc_link_xmit2(struct sk_buff *buf, u32 dnode, u32 selector)
+{
+	struct tipc_link *link = NULL;
+	struct tipc_node *node;
+	int rc = -EHOSTUNREACH;
+
+	node = tipc_node_find(dnode);
+	if (node) {
+		tipc_node_lock(node);
+		link = node->active_links[selector & 1];
+		if (link)
+			rc = __tipc_link_xmit2(link, buf);
+		tipc_node_unlock(node);
+	}
+
+	if (link)
+		return rc;
+
+	if (likely(in_own_node(dnode)))
+		return tipc_sk_rcv(buf);
+
+	kfree_skb_list(buf);
+	return rc;
+}
+
 /*
  * tipc_link_sync_xmit - synchronize broadcast link endpoints.
  *
@@ -933,252 +1072,6 @@ void tipc_link_names_xmit(struct list_head *message_list, u32 dest)
 }
 
 /*
- * tipc_link_xmit_fast: Entry for data messages where the
- * destination link is known and the header is complete,
- * inclusive total message length. Very time critical.
- * Link is locked. Returns user data length.
- */
-static int tipc_link_xmit_fast(struct tipc_link *l_ptr, struct sk_buff *buf,
-			       u32 *used_max_pkt)
-{
-	struct tipc_msg *msg = buf_msg(buf);
-	int res = msg_data_sz(msg);
-
-	if (likely(!link_congested(l_ptr))) {
-		if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
-			link_add_to_outqueue(l_ptr, buf, msg);
-			tipc_bearer_send(l_ptr->bearer_id, buf,
-					 &l_ptr->media_addr);
-			l_ptr->unacked_window = 0;
-			return res;
-		}
-		else
-			*used_max_pkt = l_ptr->max_pkt;
-	}
-	return __tipc_link_xmit(l_ptr, buf);  /* All other cases */
-}
-
-/*
- * tipc_link_iovec_xmit_fast: Entry for messages where the
- * destination processor is known and the header is complete,
- * except for total message length.
- * Returns user data length or errno.
- */
-int tipc_link_iovec_xmit_fast(struct tipc_port *sender,
-			      struct iovec const *msg_sect,
-			      unsigned int len, u32 destaddr)
-{
-	struct tipc_msg *hdr = &sender->phdr;
-	struct tipc_link *l_ptr;
-	struct sk_buff *buf;
-	struct tipc_node *node;
-	int res;
-	u32 selector = msg_origport(hdr) & 1;
-
-again:
-	/*
-	 * Try building message using port's max_pkt hint.
-	 * (Must not hold any locks while building message.)
-	 */
-	res = tipc_msg_build(hdr, msg_sect, len, sender->max_pkt, &buf);
-	/* Exit if build request was invalid */
-	if (unlikely(res < 0))
-		return res;
-
-	node = tipc_node_find(destaddr);
-	if (likely(node)) {
-		tipc_node_lock(node);
-		l_ptr = node->active_links[selector];
-		if (likely(l_ptr)) {
-			if (likely(buf)) {
-				res = tipc_link_xmit_fast(l_ptr, buf,
-							  &sender->max_pkt);
-exit:
-				tipc_node_unlock(node);
-				return res;
-			}
-
-			/* Exit if link (or bearer) is congested */
-			if (link_congested(l_ptr)) {
-				res = link_schedule_port(l_ptr,
-							 sender->ref, res);
-				goto exit;
-			}
-
-			/*
-			 * Message size exceeds max_pkt hint; update hint,
-			 * then re-try fast path or fragment the message
-			 */
-			sender->max_pkt = l_ptr->max_pkt;
-			tipc_node_unlock(node);
-
-
-			if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
-				goto again;
-
-			return tipc_link_iovec_long_xmit(sender, msg_sect,
-							 len, destaddr);
-		}
-		tipc_node_unlock(node);
-	}
-
-	/* Couldn't find a link to the destination node */
-	kfree_skb(buf);
-	tipc_port_iovec_reject(sender, hdr, msg_sect, len, TIPC_ERR_NO_NODE);
-	return -ENETUNREACH;
-}
-
-/*
- * tipc_link_iovec_long_xmit(): Entry for long messages where the
- * destination node is known and the header is complete,
- * inclusive total message length.
- * Link and bearer congestion status have been checked to be ok,
- * and are ignored if they change.
- *
- * Note that fragments do not use the full link MTU so that they won't have
- * to undergo refragmentation if link changeover causes them to be sent
- * over another link with an additional tunnel header added as prefix.
- * (Refragmentation will still occur if the other link has a smaller MTU.)
- *
- * Returns user data length or errno.
- */
-static int tipc_link_iovec_long_xmit(struct tipc_port *sender,
-				     struct iovec const *msg_sect,
-				     unsigned int len, u32 destaddr)
-{
-	struct tipc_link *l_ptr;
-	struct tipc_node *node;
-	struct tipc_msg *hdr = &sender->phdr;
-	u32 dsz = len;
-	u32 max_pkt, fragm_sz, rest;
-	struct tipc_msg fragm_hdr;
-	struct sk_buff *buf, *buf_chain, *prev;
-	u32 fragm_crs, fragm_rest, hsz, sect_rest;
-	const unchar __user *sect_crs;
-	int curr_sect;
-	u32 fragm_no;
-	int res = 0;
-
-again:
-	fragm_no = 1;
-	max_pkt = sender->max_pkt - INT_H_SIZE;
-		/* leave room for tunnel header in case of link changeover */
-	fragm_sz = max_pkt - INT_H_SIZE;
-		/* leave room for fragmentation header in each fragment */
-	rest = dsz;
-	fragm_crs = 0;
-	fragm_rest = 0;
-	sect_rest = 0;
-	sect_crs = NULL;
-	curr_sect = -1;
-
-	/* Prepare reusable fragment header */
-	tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
-		 INT_H_SIZE, msg_destnode(hdr));
-	msg_set_size(&fragm_hdr, max_pkt);
-	msg_set_fragm_no(&fragm_hdr, 1);
-
-	/* Prepare header of first fragment */
-	buf_chain = buf = tipc_buf_acquire(max_pkt);
-	if (!buf)
-		return -ENOMEM;
-	buf->next = NULL;
-	skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
-	hsz = msg_hdr_sz(hdr);
-	skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
-
-	/* Chop up message */
-	fragm_crs = INT_H_SIZE + hsz;
-	fragm_rest = fragm_sz - hsz;
-
-	do {		/* For all sections */
-		u32 sz;
-
-		if (!sect_rest) {
-			sect_rest = msg_sect[++curr_sect].iov_len;
-			sect_crs = msg_sect[curr_sect].iov_base;
-		}
-
-		if (sect_rest < fragm_rest)
-			sz = sect_rest;
-		else
-			sz = fragm_rest;
-
-		if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
-			res = -EFAULT;
-error:
-			kfree_skb_list(buf_chain);
-			return res;
-		}
-		sect_crs += sz;
-		sect_rest -= sz;
-		fragm_crs += sz;
-		fragm_rest -= sz;
-		rest -= sz;
-
-		if (!fragm_rest && rest) {
-
-			/* Initiate new fragment: */
-			if (rest <= fragm_sz) {
-				fragm_sz = rest;
-				msg_set_type(&fragm_hdr, LAST_FRAGMENT);
-			} else {
-				msg_set_type(&fragm_hdr, FRAGMENT);
-			}
-			msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
-			msg_set_fragm_no(&fragm_hdr, ++fragm_no);
-			prev = buf;
-			buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
-			if (!buf) {
-				res = -ENOMEM;
-				goto error;
-			}
-
-			buf->next = NULL;
-			prev->next = buf;
-			skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
-			fragm_crs = INT_H_SIZE;
-			fragm_rest = fragm_sz;
-		}
-	} while (rest > 0);
-
-	/*
-	 * Now we have a buffer chain. Select a link and check
-	 * that packet size is still OK
-	 */
-	node = tipc_node_find(destaddr);
-	if (likely(node)) {
-		tipc_node_lock(node);
-		l_ptr = node->active_links[sender->ref & 1];
-		if (!l_ptr) {
-			tipc_node_unlock(node);
-			goto reject;
-		}
-		if (l_ptr->max_pkt < max_pkt) {
-			sender->max_pkt = l_ptr->max_pkt;
-			tipc_node_unlock(node);
-			kfree_skb_list(buf_chain);
-			goto again;
-		}
-	} else {
-reject:
-		kfree_skb_list(buf_chain);
-		tipc_port_iovec_reject(sender, hdr, msg_sect, len,
-				       TIPC_ERR_NO_NODE);
-		return -ENETUNREACH;
-	}
-
-	/* Append chain of fragments to send queue & send them */
-	l_ptr->long_msg_seq_no++;
-	link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
-	l_ptr->stats.sent_fragments += fragm_no;
-	l_ptr->stats.sent_fragmented++;
-	tipc_link_push_queue(l_ptr);
-	tipc_node_unlock(node);
-	return dsz;
-}
-
-/*
  * tipc_link_push_packet: Push one unsent packet to the media
  */
 static u32 tipc_link_push_packet(struct tipc_link *l_ptr)
@@ -1238,7 +1131,7 @@ static u32 tipc_link_push_packet(struct tipc_link *l_ptr)
 			tipc_bearer_send(l_ptr->bearer_id, buf,
 					 &l_ptr->media_addr);
 			if (msg_user(msg) == MSG_BUNDLER)
-				msg_set_type(msg, CLOSED_MSG);
+				msg_set_type(msg, BUNDLE_CLOSED);
 			l_ptr->next_out = buf->next;
 			return 0;
 		}
@@ -1590,6 +1483,7 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
 		case TIPC_MEDIUM_IMPORTANCE:
 		case TIPC_HIGH_IMPORTANCE:
 		case TIPC_CRITICAL_IMPORTANCE:
+		case CONN_MANAGER:
 			tipc_node_unlock(n_ptr);
 			tipc_sk_rcv(buf);
 			continue;
@@ -1604,10 +1498,6 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
 			tipc_node_unlock(n_ptr);
 			tipc_named_rcv(buf);
 			continue;
-		case CONN_MANAGER:
-			tipc_node_unlock(n_ptr);
-			tipc_port_proto_rcv(buf);
-			continue;
 		case BCAST_PROTOCOL:
 			tipc_link_sync_rcv(n_ptr, buf);
 			break;
@@ -2217,6 +2107,7 @@ void tipc_link_bundle_rcv(struct sk_buff *buf)
 	u32 msgcount = msg_msgcnt(buf_msg(buf));
 	u32 pos = INT_H_SIZE;
 	struct sk_buff *obuf;
+	struct tipc_msg *omsg;
 
 	while (msgcount--) {
 		obuf = buf_extract(buf, pos);
@@ -2224,8 +2115,16 @@ void tipc_link_bundle_rcv(struct sk_buff *buf)
 			pr_warn("Link unable to unbundle message(s)\n");
 			break;
 		}
-		pos += align(msg_size(buf_msg(obuf)));
-		tipc_net_route_msg(obuf);
+		omsg = buf_msg(obuf);
+		pos += align(msg_size(omsg));
+		if (msg_isdata(omsg) || (msg_user(omsg) == CONN_MANAGER)) {
+			tipc_sk_rcv(obuf);
+		} else if (msg_user(omsg) == NAME_DISTRIBUTOR) {
+			tipc_named_rcv(obuf);
+		} else {
+			pr_warn("Illegal bundled msg: %u\n", msg_user(omsg));
+			kfree_skb(obuf);
+		}
 	}
 	kfree_skb(buf);
 }