[RESEND PATCH 5/7] net: qrtr: Clean up control packet handling

From: Bjorn Andersson
Date: Wed Oct 04 2017 - 23:52:29 EST


As the message header generation is deferred the internal functions for
generating control packets can be simplified.

This patch modifies qrtr_alloc_ctrl_packet() to, in addition to the
sk_buff, return a reference to a struct qrtr_ctrl_pkt, which clarifies
and simplifies the helpers to the point that these functions can be
folded back into the callers.

Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---
net/qrtr/qrtr.c | 93 ++++++++++++++++++---------------------------------------
1 file changed, 29 insertions(+), 64 deletions(-)

diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
index 82dc83789310..a84edba7b1ef 100644
--- a/net/qrtr/qrtr.c
+++ b/net/qrtr/qrtr.c
@@ -255,9 +255,18 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
}
EXPORT_SYMBOL_GPL(qrtr_endpoint_post);

-static struct sk_buff *qrtr_alloc_ctrl_packet(u32 type, size_t pkt_len,
- u32 src_node, u32 dst_node)
+/**
+ * qrtr_alloc_ctrl_packet() - allocate control packet skb
+ * @pkt: reference to qrtr_ctrl_pkt pointer
+ *
+ * Returns newly allocated sk_buff, or NULL on failure
+ *
+ * This function allocates a sk_buff large enough to carry a qrtr_ctrl_pkt and
+ * on success returns a reference to the control packet in @pkt.
+ */
+static struct sk_buff *qrtr_alloc_ctrl_packet(struct qrtr_ctrl_pkt **pkt)
{
+ const int pkt_len = sizeof(struct qrtr_ctrl_pkt);
struct sk_buff *skb;

skb = alloc_skb(QRTR_HDR_SIZE + pkt_len, GFP_KERNEL);
@@ -265,64 +274,7 @@ static struct sk_buff *qrtr_alloc_ctrl_packet(u32 type, size_t pkt_len,
return NULL;

skb_reserve(skb, QRTR_HDR_SIZE);
-
- return skb;
-}
-
-/* Allocate and construct a resume-tx packet. */
-static struct sk_buff *qrtr_alloc_resume_tx(u32 src_node,
- u32 dst_node, u32 port)
-{
- const int pkt_len = 20;
- struct sk_buff *skb;
- __le32 *buf;
-
- skb = qrtr_alloc_ctrl_packet(QRTR_TYPE_RESUME_TX, pkt_len,
- src_node, dst_node);
- if (!skb)
- return NULL;
-
- buf = skb_put_zero(skb, pkt_len);
- buf[0] = cpu_to_le32(QRTR_TYPE_RESUME_TX);
- buf[1] = cpu_to_le32(src_node);
- buf[2] = cpu_to_le32(port);
-
- return skb;
-}
-
-/* Allocate and construct a BYE message to signal remote termination */
-static struct sk_buff *qrtr_alloc_local_bye(u32 src_node)
-{
- const int pkt_len = 20;
- struct sk_buff *skb;
- __le32 *buf;
-
- skb = qrtr_alloc_ctrl_packet(QRTR_TYPE_BYE, pkt_len,
- src_node, qrtr_local_nid);
- if (!skb)
- return NULL;
-
- buf = skb_put_zero(skb, pkt_len);
- buf[0] = cpu_to_le32(QRTR_TYPE_BYE);
-
- return skb;
-}
-
-static struct sk_buff *qrtr_alloc_del_client(struct sockaddr_qrtr *sq)
-{
- const int pkt_len = 20;
- struct sk_buff *skb;
- __le32 *buf;
-
- skb = qrtr_alloc_ctrl_packet(QRTR_TYPE_DEL_CLIENT, pkt_len,
- sq->sq_node, QRTR_NODE_BCAST);
- if (!skb)
- return NULL;
-
- buf = skb_put_zero(skb, pkt_len);
- buf[0] = cpu_to_le32(QRTR_TYPE_DEL_CLIENT);
- buf[1] = cpu_to_le32(sq->sq_node);
- buf[2] = cpu_to_le32(sq->sq_port);
+ *pkt = skb_put_zero(skb, pkt_len);

return skb;
}
@@ -337,6 +289,7 @@ static void qrtr_port_put(struct qrtr_sock *ipc);
static void qrtr_node_rx_work(struct work_struct *work)
{
struct qrtr_node *node = container_of(work, struct qrtr_node, work);
+ struct qrtr_ctrl_pkt *pkt;
struct sockaddr_qrtr dst;
struct sockaddr_qrtr src;
struct sk_buff *skb;
@@ -372,10 +325,14 @@ static void qrtr_node_rx_work(struct work_struct *work)
}

if (confirm) {
- skb = qrtr_alloc_resume_tx(dst_node, node->nid, dst_port);
+ skb = qrtr_alloc_ctrl_packet(&pkt);
if (!skb)
break;

+ pkt->cmd = cpu_to_le32(QRTR_TYPE_RESUME_TX);
+ pkt->client.node = cpu_to_le32(dst.sq_node);
+ pkt->client.port = cpu_to_le32(dst.sq_port);
+
if (qrtr_node_enqueue(node, skb, QRTR_TYPE_RESUME_TX,
&dst, &src))
break;
@@ -429,6 +386,7 @@ void qrtr_endpoint_unregister(struct qrtr_endpoint *ep)
struct qrtr_node *node = ep->node;
struct sockaddr_qrtr src = {AF_QIPCRTR, node->nid, QRTR_PORT_CTRL};
struct sockaddr_qrtr dst = {AF_QIPCRTR, qrtr_local_nid, QRTR_PORT_CTRL};
+ struct qrtr_ctrl_pkt *pkt;
struct sk_buff *skb;

mutex_lock(&node->ep_lock);
@@ -436,9 +394,11 @@ void qrtr_endpoint_unregister(struct qrtr_endpoint *ep)
mutex_unlock(&node->ep_lock);

/* Notify the local controller about the event */
- skb = qrtr_alloc_local_bye(node->nid);
- if (skb)
+ skb = qrtr_alloc_ctrl_packet(&pkt);
+ if (skb) {
+ pkt->cmd = cpu_to_le32(QRTR_TYPE_BYE);
qrtr_local_enqueue(NULL, skb, QRTR_TYPE_BYE, &src, &dst);
+ }

qrtr_node_release(node);
ep->node = NULL;
@@ -474,6 +434,7 @@ static void qrtr_port_put(struct qrtr_sock *ipc)
/* Remove port assignment. */
static void qrtr_port_remove(struct qrtr_sock *ipc)
{
+ struct qrtr_ctrl_pkt *pkt;
struct sk_buff *skb;
int port = ipc->us.sq_port;
struct sockaddr_qrtr to;
@@ -482,8 +443,12 @@ static void qrtr_port_remove(struct qrtr_sock *ipc)
to.sq_node = QRTR_NODE_BCAST;
to.sq_port = QRTR_PORT_CTRL;

- skb = qrtr_alloc_del_client(&ipc->us);
+ skb = qrtr_alloc_ctrl_packet(&pkt);
if (skb) {
+ pkt->cmd = cpu_to_le32(QRTR_TYPE_DEL_CLIENT);
+ pkt->client.node = cpu_to_le32(ipc->us.sq_node);
+ pkt->client.port = cpu_to_le32(ipc->us.sq_port);
+
skb_set_owner_w(skb, &ipc->sk);
qrtr_bcast_enqueue(NULL, skb, QRTR_TYPE_DEL_CLIENT, &ipc->us,
&to);
--
2.12.0