Merge branch 'tipc-next'

Ying Xue says:

====================
standardize TIPC SKB queue operations

Now the following SKB queues are created and maintained within internal
TIPC stack:

- link transmission queue
- link deferred queue
- link receive queue
- socket outgoing packet chain
- name table outgoing packet chain

In order to manage above queues, TIPC stack declares a sk_buff pointer
for each queue to record its head, and directly modifies "prev" and
"next" SKB pointers of SKB structure when inserting or deleting a SKB
to or from the queue. As these operations are pretty complex, they
easily involve fatal mistakes. If these sk_buff pointers are replaced
with sk_buff_head instances as queue heads and corresponding generic
SKB list APIs are used to manage them, the entire TIPC code would
become quite clean and readable. But before make the change, we need
to clean up below redundant functionalities:

- remove node subscribe infrastructure
- remove protocol message queue
- remove retransmission queue
- clean up process of pushing packets in link layer
====================

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

1 files changed, 62 insertions, 63 deletions

diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index 9155496b8a8..5b0659791c0 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -166,11 +166,12 @@ err:
  * @offset: Posision in iov to start copying from
  * @dsz: Total length of user data
  * @pktmax: Max packet size that can be used
- * @chain: Buffer or chain of buffers to be returned to caller
+ * @list: Buffer or chain of buffers to be returned to caller
+ *
  * Returns message data size or errno: -ENOMEM, -EFAULT
  */
-int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
-		   int offset, int dsz, int pktmax , struct sk_buff **chain)
+int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset,
+		   int dsz, int pktmax, struct sk_buff_head *list)
 {
 	int mhsz = msg_hdr_sz(mhdr);
 	int msz = mhsz + dsz;
@@ -179,22 +180,22 @@ int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
 	int pktrem = pktmax;
 	int drem = dsz;
 	struct tipc_msg pkthdr;
-	struct sk_buff *buf, *prev;
+	struct sk_buff *skb;
 	char *pktpos;
 	int rc;
-	uint chain_sz = 0;
+
 	msg_set_size(mhdr, msz);
 
 	/* No fragmentation needed? */
 	if (likely(msz <= pktmax)) {
-		buf = tipc_buf_acquire(msz);
-		*chain = buf;
-		if (unlikely(!buf))
+		skb = tipc_buf_acquire(msz);
+		if (unlikely(!skb))
 			return -ENOMEM;
-		skb_copy_to_linear_data(buf, mhdr, mhsz);
-		pktpos = buf->data + mhsz;
-		TIPC_SKB_CB(buf)->chain_sz = 1;
-		if (!dsz || !memcpy_fromiovecend(pktpos, m->msg_iov, offset, dsz))
+		__skb_queue_tail(list, skb);
+		skb_copy_to_linear_data(skb, mhdr, mhsz);
+		pktpos = skb->data + mhsz;
+		if (!dsz || !memcpy_fromiovecend(pktpos, m->msg_iov, offset,
+						 dsz))
 			return dsz;
 		rc = -EFAULT;
 		goto error;
@@ -207,15 +208,15 @@ int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
 	msg_set_fragm_no(&pkthdr, pktno);
 
 	/* Prepare first fragment */
-	*chain = buf = tipc_buf_acquire(pktmax);
-	if (!buf)
+	skb = tipc_buf_acquire(pktmax);
+	if (!skb)
 		return -ENOMEM;
-	chain_sz = 1;
-	pktpos = buf->data;
-	skb_copy_to_linear_data(buf, &pkthdr, INT_H_SIZE);
+	__skb_queue_tail(list, skb);
+	pktpos = skb->data;
+	skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
 	pktpos += INT_H_SIZE;
 	pktrem -= INT_H_SIZE;
-	skb_copy_to_linear_data_offset(buf, INT_H_SIZE, mhdr, mhsz);
+	skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz);
 	pktpos += mhsz;
 	pktrem -= mhsz;
 
@@ -238,43 +239,41 @@ int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
 			pktsz = drem + INT_H_SIZE;
 		else
 			pktsz = pktmax;
-		prev = buf;
-		buf = tipc_buf_acquire(pktsz);
-		if (!buf) {
+		skb = tipc_buf_acquire(pktsz);
+		if (!skb) {
 			rc = -ENOMEM;
 			goto error;
 		}
-		chain_sz++;
-		prev->next = buf;
+		__skb_queue_tail(list, skb);
 		msg_set_type(&pkthdr, FRAGMENT);
 		msg_set_size(&pkthdr, pktsz);
 		msg_set_fragm_no(&pkthdr, ++pktno);
-		skb_copy_to_linear_data(buf, &pkthdr, INT_H_SIZE);
-		pktpos = buf->data + INT_H_SIZE;
+		skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
+		pktpos = skb->data + INT_H_SIZE;
 		pktrem = pktsz - INT_H_SIZE;
 
 	} while (1);
-	TIPC_SKB_CB(*chain)->chain_sz = chain_sz;
-	msg_set_type(buf_msg(buf), LAST_FRAGMENT);
+	msg_set_type(buf_msg(skb), LAST_FRAGMENT);
 	return dsz;
 error:
-	kfree_skb_list(*chain);
-	*chain = NULL;
+	__skb_queue_purge(list);
+	__skb_queue_head_init(list);
 	return rc;
 }
 
 /**
  * tipc_msg_bundle(): Append contents of a buffer to tail of an existing one
- * @bbuf: the existing buffer ("bundle")
- * @buf:  buffer to be appended
+ * @list: the buffer chain of the existing buffer ("bundle")
+ * @skb:  buffer to be appended
  * @mtu:  max allowable size for the bundle buffer
  * Consumes buffer if successful
  * Returns true if bundling could be performed, otherwise false
  */
-bool tipc_msg_bundle(struct sk_buff *bbuf, struct sk_buff *buf, u32 mtu)
+bool tipc_msg_bundle(struct sk_buff_head *list, struct sk_buff *skb, u32 mtu)
 {
-	struct tipc_msg *bmsg = buf_msg(bbuf);
-	struct tipc_msg *msg = buf_msg(buf);
+	struct sk_buff *bskb = skb_peek_tail(list);
+	struct tipc_msg *bmsg = buf_msg(bskb);
+	struct tipc_msg *msg = buf_msg(skb);
 	unsigned int bsz = msg_size(bmsg);
 	unsigned int msz = msg_size(msg);
 	u32 start = align(bsz);
@@ -289,35 +288,36 @@ bool tipc_msg_bundle(struct sk_buff *bbuf, struct sk_buff *buf, u32 mtu)
 		return false;
 	if (likely(msg_user(bmsg) != MSG_BUNDLER))
 		return false;
-	if (likely(msg_type(bmsg) != BUNDLE_OPEN))
+	if (likely(!TIPC_SKB_CB(bskb)->bundling))
 		return false;
-	if (unlikely(skb_tailroom(bbuf) < (pad + msz)))
+	if (unlikely(skb_tailroom(bskb) < (pad + msz)))
 		return false;
 	if (unlikely(max < (start + msz)))
 		return false;
 
-	skb_put(bbuf, pad + msz);
-	skb_copy_to_linear_data_offset(bbuf, start, buf->data, msz);
+	skb_put(bskb, pad + msz);
+	skb_copy_to_linear_data_offset(bskb, start, skb->data, msz);
 	msg_set_size(bmsg, start + msz);
 	msg_set_msgcnt(bmsg, msg_msgcnt(bmsg) + 1);
-	bbuf->next = buf->next;
-	kfree_skb(buf);
+	kfree_skb(skb);
 	return true;
 }
 
 /**
  * tipc_msg_make_bundle(): Create bundle buf and append message to its tail
- * @buf:  buffer to be appended and replaced
- * @mtu:  max allowable size for the bundle buffer, inclusive header
+ * @list: the buffer chain
+ * @skb: buffer to be appended and replaced
+ * @mtu: max allowable size for the bundle buffer, inclusive header
  * @dnode: destination node for message. (Not always present in header)
  * Replaces buffer if successful
  * Returns true if success, otherwise false
  */
-bool tipc_msg_make_bundle(struct sk_buff **buf, u32 mtu, u32 dnode)
+bool tipc_msg_make_bundle(struct sk_buff_head *list, struct sk_buff *skb,
+			  u32 mtu, u32 dnode)
 {
-	struct sk_buff *bbuf;
+	struct sk_buff *bskb;
 	struct tipc_msg *bmsg;
-	struct tipc_msg *msg = buf_msg(*buf);
+	struct tipc_msg *msg = buf_msg(skb);
 	u32 msz = msg_size(msg);
 	u32 max = mtu - INT_H_SIZE;
 
@@ -330,20 +330,19 @@ bool tipc_msg_make_bundle(struct sk_buff **buf, u32 mtu, u32 dnode)
 	if (msz > (max / 2))
 		return false;
 
-	bbuf = tipc_buf_acquire(max);
-	if (!bbuf)
+	bskb = tipc_buf_acquire(max);
+	if (!bskb)
 		return false;
 
-	skb_trim(bbuf, INT_H_SIZE);
-	bmsg = buf_msg(bbuf);
-	tipc_msg_init(bmsg, MSG_BUNDLER, BUNDLE_OPEN, INT_H_SIZE, dnode);
+	skb_trim(bskb, INT_H_SIZE);
+	bmsg = buf_msg(bskb);
+	tipc_msg_init(bmsg, MSG_BUNDLER, 0, INT_H_SIZE, dnode);
 	msg_set_seqno(bmsg, msg_seqno(msg));
 	msg_set_ack(bmsg, msg_ack(msg));
 	msg_set_bcast_ack(bmsg, msg_bcast_ack(msg));
-	bbuf->next = (*buf)->next;
-	tipc_msg_bundle(bbuf, *buf, mtu);
-	*buf = bbuf;
-	return true;
+	TIPC_SKB_CB(bskb)->bundling = true;
+	__skb_queue_tail(list, bskb);
+	return tipc_msg_bundle(list, skb, mtu);
 }
 
 /**
@@ -429,22 +428,23 @@ int tipc_msg_eval(struct sk_buff *buf, u32 *dnode)
 /* tipc_msg_reassemble() - clone a buffer chain of fragments and
  *                         reassemble the clones into one message
  */
-struct sk_buff *tipc_msg_reassemble(struct sk_buff *chain)
+struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list)
 {
-	struct sk_buff *buf = chain;
-	struct sk_buff *frag = buf;
+	struct sk_buff *skb;
+	struct sk_buff *frag = NULL;
 	struct sk_buff *head = NULL;
 	int hdr_sz;
 
 	/* Copy header if single buffer */
-	if (!buf->next) {
-		hdr_sz = skb_headroom(buf) + msg_hdr_sz(buf_msg(buf));
-		return __pskb_copy(buf, hdr_sz, GFP_ATOMIC);
+	if (skb_queue_len(list) == 1) {
+		skb = skb_peek(list);
+		hdr_sz = skb_headroom(skb) + msg_hdr_sz(buf_msg(skb));
+		return __pskb_copy(skb, hdr_sz, GFP_ATOMIC);
 	}
 
 	/* Clone all fragments and reassemble */
-	while (buf) {
-		frag = skb_clone(buf, GFP_ATOMIC);
+	skb_queue_walk(list, skb) {
+		frag = skb_clone(skb, GFP_ATOMIC);
 		if (!frag)
 			goto error;
 		frag->next = NULL;
@@ -452,7 +452,6 @@ struct sk_buff *tipc_msg_reassemble(struct sk_buff *chain)
 			break;
 		if (!head)
 			goto error;
-		buf = buf->next;
 	}
 	return frag;
 error: