From 64f9eca06415dc820ff8a2263f846dc8199adb50 Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Wed, 7 Jun 2017 14:07:36 -0700 Subject: [PATCH 1/4] net: qrtr: Refactor packet allocation Extract the allocation and filling in the control message header fields to a separate function in order to reuse this in subsequent patches. Cc: Courtney Cavin Signed-off-by: Bjorn Andersson Signed-off-by: David S. Miller --- net/qrtr/qrtr.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c index a9a8c7d5a4a9..86d35ed50da9 100644 --- a/net/qrtr/qrtr.c +++ b/net/qrtr/qrtr.c @@ -245,14 +245,11 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len) } EXPORT_SYMBOL_GPL(qrtr_endpoint_post); -/* Allocate and construct a resume-tx packet. */ -static struct sk_buff *qrtr_alloc_resume_tx(u32 src_node, - u32 dst_node, u32 port) +static struct sk_buff *qrtr_alloc_ctrl_packet(u32 type, size_t pkt_len, + u32 src_node, u32 dst_node) { - const int pkt_len = 20; struct qrtr_hdr *hdr; struct sk_buff *skb; - __le32 *buf; skb = alloc_skb(QRTR_HDR_SIZE + pkt_len, GFP_KERNEL); if (!skb) @@ -261,7 +258,7 @@ static struct sk_buff *qrtr_alloc_resume_tx(u32 src_node, hdr = (struct qrtr_hdr *)skb_put(skb, QRTR_HDR_SIZE); hdr->version = cpu_to_le32(QRTR_PROTO_VER); - hdr->type = cpu_to_le32(QRTR_TYPE_RESUME_TX); + hdr->type = cpu_to_le32(type); hdr->src_node_id = cpu_to_le32(src_node); hdr->src_port_id = cpu_to_le32(QRTR_PORT_CTRL); hdr->confirm_rx = cpu_to_le32(0); @@ -269,6 +266,22 @@ static struct sk_buff *qrtr_alloc_resume_tx(u32 src_node, hdr->dst_node_id = cpu_to_le32(dst_node); hdr->dst_port_id = cpu_to_le32(QRTR_PORT_CTRL); + 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 = (__le32 *)skb_put(skb, pkt_len); memset(buf, 0, pkt_len); buf[0] = cpu_to_le32(QRTR_TYPE_RESUME_TX); From 8acc8ee465e69ed47bc9cde8d271a1189648d762 Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Wed, 7 Jun 2017 14:07:37 -0700 Subject: [PATCH 2/4] net: qrtr: Inject BYE on remote termination Per the QMUX protocol specification a terminating node can send a BYE control message to signal that the link is going down, upon receiving this all information about remote services should be discarded and local clients should be notified. In the event that the link was brought down abruptly the router is supposed to act like a BYE message has arrived. As there is no harm in receiving an extra BYE from the remote this patch implements the latter by injecting a BYE when the link to the remote is unregistered. The name service will receive the BYE and can implement the notification to the local clients. Cc: Courtney Cavin Signed-off-by: Bjorn Andersson Signed-off-by: David S. Miller --- net/qrtr/qrtr.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c index 86d35ed50da9..e8cbab23d667 100644 --- a/net/qrtr/qrtr.c +++ b/net/qrtr/qrtr.c @@ -111,6 +111,8 @@ struct qrtr_node { struct list_head item; }; +static int qrtr_local_enqueue(struct qrtr_node *node, struct sk_buff *skb); + /* Release node resources and free the node. * * Do not call directly, use qrtr_node_release. To be used with @@ -291,6 +293,25 @@ static struct sk_buff *qrtr_alloc_resume_tx(u32 src_node, 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 = (__le32 *)skb_put(skb, pkt_len); + memset(buf, 0, pkt_len); + buf[0] = cpu_to_le32(QRTR_TYPE_BYE); + + return skb; +} + static struct qrtr_sock *qrtr_port_lookup(int port); static void qrtr_port_put(struct qrtr_sock *ipc); @@ -382,11 +403,17 @@ EXPORT_SYMBOL_GPL(qrtr_endpoint_register); void qrtr_endpoint_unregister(struct qrtr_endpoint *ep) { struct qrtr_node *node = ep->node; + struct sk_buff *skb; mutex_lock(&node->ep_lock); node->ep = NULL; mutex_unlock(&node->ep_lock); + /* Notify the local controller about the event */ + skb = qrtr_alloc_local_bye(node->nid); + if (skb) + qrtr_local_enqueue(NULL, skb); + qrtr_node_release(node); ep->node = NULL; } From 1784473b242585f407d3e75654d5b06f462a355b Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Wed, 7 Jun 2017 14:07:38 -0700 Subject: [PATCH 3/4] net: qrtr: Broadcast DEL_CLIENT message when endpoint is closed Per the QMUXv2 protocol specificiation a DEL_CLIENT message should be broadcasted when an endpoint is disconnected. The protocol specification does suggest that the router can keep track of which nodes the endpoint has been communicating with to not wake up sleeping remotes unecessarily, but implementation of this suggestion is left for the future. Cc: Courtney Cavin Signed-off-by: Bjorn Andersson Signed-off-by: David S. Miller --- net/qrtr/qrtr.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c index e8cbab23d667..d7516098b5aa 100644 --- a/net/qrtr/qrtr.c +++ b/net/qrtr/qrtr.c @@ -112,6 +112,7 @@ struct qrtr_node { }; static int qrtr_local_enqueue(struct qrtr_node *node, struct sk_buff *skb); +static int qrtr_bcast_enqueue(struct qrtr_node *node, struct sk_buff *skb); /* Release node resources and free the node. * @@ -312,6 +313,26 @@ static struct sk_buff *qrtr_alloc_local_bye(u32 src_node) 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 = (__le32 *)skb_put(skb, pkt_len); + memset(buf, 0, 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); + + return skb; +} + static struct qrtr_sock *qrtr_port_lookup(int port); static void qrtr_port_put(struct qrtr_sock *ipc); @@ -448,8 +469,15 @@ static void qrtr_port_put(struct qrtr_sock *ipc) /* Remove port assignment. */ static void qrtr_port_remove(struct qrtr_sock *ipc) { + struct sk_buff *skb; int port = ipc->us.sq_port; + skb = qrtr_alloc_del_client(&ipc->us); + if (skb) { + skb_set_owner_w(skb, &ipc->sk); + qrtr_bcast_enqueue(NULL, skb); + } + if (port == QRTR_PORT_CTRL) port = 0; From b24844b1b537c34e3069c4bcfb448a5a05c9e0dc Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Wed, 7 Jun 2017 14:07:39 -0700 Subject: [PATCH 4/4] net: qrtr: Inform open sockets about new controller As the higher level communication only deals with "services" the a service directory is required to keep track of local and remote services. In order for qrtr clients to be informed about when the service directory implementation is available some event needs to be passed to them. Rather than introducing support for broadcasting such a message in-band to all open local sockets we flag each socket with ENETRESET, as there are no other expected operations that would benefit from having support from locally broadcasting messages. Cc: Courtney Cavin Signed-off-by: Bjorn Andersson Signed-off-by: David S. Miller --- net/qrtr/qrtr.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c index d7516098b5aa..c7a5d861906b 100644 --- a/net/qrtr/qrtr.c +++ b/net/qrtr/qrtr.c @@ -530,6 +530,26 @@ static int qrtr_port_assign(struct qrtr_sock *ipc, int *port) return 0; } +/* Reset all non-control ports */ +static void qrtr_reset_ports(void) +{ + struct qrtr_sock *ipc; + int id; + + mutex_lock(&qrtr_port_lock); + idr_for_each_entry(&qrtr_ports, ipc, id) { + /* Don't reset control port */ + if (id == 0) + continue; + + sock_hold(&ipc->sk); + ipc->sk.sk_err = ENETRESET; + wake_up_interruptible(sk_sleep(&ipc->sk)); + sock_put(&ipc->sk); + } + mutex_unlock(&qrtr_port_lock); +} + /* Bind socket to address. * * Socket should be locked upon call. @@ -558,6 +578,10 @@ static int __qrtr_bind(struct socket *sock, sock_reset_flag(sk, SOCK_ZAPPED); + /* Notify all open ports about the new controller */ + if (port == QRTR_PORT_CTRL) + qrtr_reset_ports(); + return 0; }