net: Add Qualcomm IPC router

Add an implementation of Qualcomm's IPC router protocol, used to
communicate with service providing remote processors.
Signed-off-by: NCourtney Cavin <courtney.cavin@sonymobile.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@sonymobile.com>
[bjorn: Cope with 0 being a valid node id and implement RTM_NEWADDR]
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/socket.h

@@ -201,8 +201,9 @@ struct ucred {
 #define AF_NFC		39	/* NFC sockets			*/
 #define AF_VSOCK	40	/* vSockets			*/
 #define AF_KCM		41	/* Kernel Connection Multiplexor*/
+#define AF_QIPCRTR	42	/* Qualcomm IPC Router          */
 
-#define AF_MAX		42	/* For now.. */
+#define AF_MAX		43	/* For now.. */
 
 /* Protocol families, same as address families. */
 #define PF_UNSPEC	AF_UNSPEC
@@ -249,6 +250,7 @@ struct ucred {
 #define PF_NFC		AF_NFC
 #define PF_VSOCK	AF_VSOCK
 #define PF_KCM		AF_KCM
+#define PF_QIPCRTR	AF_QIPCRTR
 #define PF_MAX		AF_MAX
 
 /* Maximum queue length specifiable by listen.  */

include/uapi/linux/qrtr.h

+#ifndef _LINUX_QRTR_H
+#define _LINUX_QRTR_H
+
+#include <linux/socket.h>
+
+struct sockaddr_qrtr {
+	__kernel_sa_family_t sq_family;
+	__u32 sq_node;
+	__u32 sq_port;
+};
+
+#endif /* _LINUX_QRTR_H */

net/Kconfig

@@ -236,6 +236,7 @@ source "net/mpls/Kconfig"
 source "net/hsr/Kconfig"
 source "net/switchdev/Kconfig"
 source "net/l3mdev/Kconfig"
+source "net/qrtr/Kconfig"
 
 config RPS
 	bool

net/Makefile

@@ -78,3 +78,4 @@ endif
 ifneq ($(CONFIG_NET_L3_MASTER_DEV),)
 obj-y				+= l3mdev/
 endif
+obj-$(CONFIG_QRTR)		+= qrtr/

net/qrtr/Kconfig

+# Qualcomm IPC Router configuration
+#
+
+config QRTR
+	tristate "Qualcomm IPC Router support"
+	depends on ARCH_QCOM || COMPILE_TEST
+	---help---
+	  Say Y if you intend to use Qualcomm IPC router protocol.  The
+	  protocol is used to communicate with services provided by other
+	  hardware blocks in the system.
+
+	  In order to do service lookups, a userspace daemon is required to
+	  maintain a service listing.
+
+if QRTR
+
+config QRTR_SMD
+	tristate "SMD IPC Router channels"
+	depends on QCOM_SMD || COMPILE_TEST
+	---help---
+	  Say Y here to support SMD based ipcrouter channels.  SMD is the
+	  most common transport for IPC Router.
+
+endif # QRTR

net/qrtr/Makefile

+obj-$(CONFIG_QRTR) := qrtr.o
+obj-$(CONFIG_QRTR_SMD) += smd.o

net/qrtr/qrtr.c

+/*
+ * Copyright (c) 2015, Sony Mobile Communications Inc.
+ * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/module.h>
+#include <linux/netlink.h>
+#include <linux/qrtr.h>
+#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
+
+#include <net/sock.h>
+
+#include "qrtr.h"
+
+#define QRTR_PROTO_VER 1
+
+/* auto-bind range */
+#define QRTR_MIN_EPH_SOCKET 0x4000
+#define QRTR_MAX_EPH_SOCKET 0x7fff
+
+enum qrtr_pkt_type {
+	QRTR_TYPE_DATA		= 1,
+	QRTR_TYPE_HELLO		= 2,
+	QRTR_TYPE_BYE		= 3,
+	QRTR_TYPE_NEW_SERVER	= 4,
+	QRTR_TYPE_DEL_SERVER	= 5,
+	QRTR_TYPE_DEL_CLIENT	= 6,
+	QRTR_TYPE_RESUME_TX	= 7,
+	QRTR_TYPE_EXIT		= 8,
+	QRTR_TYPE_PING		= 9,
+};
+
+/**
+ * struct qrtr_hdr - (I|R)PCrouter packet header
+ * @version: protocol version
+ * @type: packet type; one of QRTR_TYPE_*
+ * @src_node_id: source node
+ * @src_port_id: source port
+ * @confirm_rx: boolean; whether a resume-tx packet should be send in reply
+ * @size: length of packet, excluding this header
+ * @dst_node_id: destination node
+ * @dst_port_id: destination port
+ */
+struct qrtr_hdr {
+	__le32 version;
+	__le32 type;
+	__le32 src_node_id;
+	__le32 src_port_id;
+	__le32 confirm_rx;
+	__le32 size;
+	__le32 dst_node_id;
+	__le32 dst_port_id;
+} __packed;
+
+#define QRTR_HDR_SIZE sizeof(struct qrtr_hdr)
+#define QRTR_NODE_BCAST ((unsigned int)-1)
+#define QRTR_PORT_CTRL ((unsigned int)-2)
+
+struct qrtr_sock {
+	/* WARNING: sk must be the first member */
+	struct sock sk;
+	struct sockaddr_qrtr us;
+	struct sockaddr_qrtr peer;
+};
+
+static inline struct qrtr_sock *qrtr_sk(struct sock *sk)
+{
+	BUILD_BUG_ON(offsetof(struct qrtr_sock, sk) != 0);
+	return container_of(sk, struct qrtr_sock, sk);
+}
+
+static unsigned int qrtr_local_nid = -1;
+
+/* for node ids */
+static RADIX_TREE(qrtr_nodes, GFP_KERNEL);
+/* broadcast list */
+static LIST_HEAD(qrtr_all_nodes);
+/* lock for qrtr_nodes, qrtr_all_nodes and node reference */
+static DEFINE_MUTEX(qrtr_node_lock);
+
+/* local port allocation management */
+static DEFINE_IDR(qrtr_ports);
+static DEFINE_MUTEX(qrtr_port_lock);
+
+/**
+ * struct qrtr_node - endpoint node
+ * @ep_lock: lock for endpoint management and callbacks
+ * @ep: endpoint
+ * @ref: reference count for node
+ * @nid: node id
+ * @rx_queue: receive queue
+ * @work: scheduled work struct for recv work
+ * @item: list item for broadcast list
+ */
+struct qrtr_node {
+	struct mutex ep_lock;
+	struct qrtr_endpoint *ep;
+	struct kref ref;
+	unsigned int nid;
+
+	struct sk_buff_head rx_queue;
+	struct work_struct work;
+	struct list_head item;
+};
+
+/* Release node resources and free the node.
+ *
+ * Do not call directly, use qrtr_node_release.  To be used with
+ * kref_put_mutex.  As such, the node mutex is expected to be locked on call.
+ */
+static void __qrtr_node_release(struct kref *kref)
+{
+	struct qrtr_node *node = container_of(kref, struct qrtr_node, ref);
+
+	if (node->nid != QRTR_EP_NID_AUTO)
+		radix_tree_delete(&qrtr_nodes, node->nid);
+
+	list_del(&node->item);
+	mutex_unlock(&qrtr_node_lock);
+
+	skb_queue_purge(&node->rx_queue);
+	kfree(node);
+}
+
+/* Increment reference to node. */
+static struct qrtr_node *qrtr_node_acquire(struct qrtr_node *node)
+{
+	if (node)
+		kref_get(&node->ref);
+	return node;
+}
+
+/* Decrement reference to node and release as necessary. */
+static void qrtr_node_release(struct qrtr_node *node)
+{
+	if (!node)
+		return;
+	kref_put_mutex(&node->ref, __qrtr_node_release, &qrtr_node_lock);
+}
+
+/* Pass an outgoing packet socket buffer to the endpoint driver. */
+static int qrtr_node_enqueue(struct qrtr_node *node, struct sk_buff *skb)
+{
+	int rc = -ENODEV;
+
+	mutex_lock(&node->ep_lock);
+	if (node->ep)
+		rc = node->ep->xmit(node->ep, skb);
+	else
+		kfree_skb(skb);
+	mutex_unlock(&node->ep_lock);
+
+	return rc;
+}
+
+/* Lookup node by id.
+ *
+ * callers must release with qrtr_node_release()
+ */
+static struct qrtr_node *qrtr_node_lookup(unsigned int nid)
+{
+	struct qrtr_node *node;
+
+	mutex_lock(&qrtr_node_lock);
+	node = radix_tree_lookup(&qrtr_nodes, nid);
+	node = qrtr_node_acquire(node);
+	mutex_unlock(&qrtr_node_lock);
+
+	return node;
+}
+
+/* Assign node id to node.
+ *
+ * This is mostly useful for automatic node id assignment, based on
+ * the source id in the incoming packet.
+ */
+static void qrtr_node_assign(struct qrtr_node *node, unsigned int nid)
+{
+	if (node->nid != QRTR_EP_NID_AUTO || nid == QRTR_EP_NID_AUTO)
+		return;
+
+	mutex_lock(&qrtr_node_lock);
+	radix_tree_insert(&qrtr_nodes, nid, node);
+	node->nid = nid;
+	mutex_unlock(&qrtr_node_lock);
+}
+
+/**
+ * qrtr_endpoint_post() - post incoming data
+ * @ep: endpoint handle
+ * @data: data pointer
+ * @len: size of data in bytes
+ *
+ * Return: 0 on success; negative error code on failure
+ */
+int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
+{
+	struct qrtr_node *node = ep->node;
+	const struct qrtr_hdr *phdr = data;
+	struct sk_buff *skb;
+	unsigned int psize;
+	unsigned int size;
+	unsigned int type;
+	unsigned int ver;
+	unsigned int dst;
+
+	if (len < QRTR_HDR_SIZE || len & 3)
+		return -EINVAL;
+
+	ver = le32_to_cpu(phdr->version);
+	size = le32_to_cpu(phdr->size);
+	type = le32_to_cpu(phdr->type);
+	dst = le32_to_cpu(phdr->dst_port_id);
+
+	psize = (size + 3) & ~3;
+
+	if (ver != QRTR_PROTO_VER)
+		return -EINVAL;
+
+	if (len != psize + QRTR_HDR_SIZE)
+		return -EINVAL;
+
+	if (dst != QRTR_PORT_CTRL && type != QRTR_TYPE_DATA)
+		return -EINVAL;
+
+	skb = netdev_alloc_skb(NULL, len);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_reset_transport_header(skb);
+	memcpy(skb_put(skb, len), data, len);
+
+	skb_queue_tail(&node->rx_queue, skb);
+	schedule_work(&node->work);
+
+	return 0;
+}
+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)
+{
+	const int pkt_len = 20;
+	struct qrtr_hdr *hdr;
+	struct sk_buff *skb;
+	u32 *buf;
+
+	skb = alloc_skb(QRTR_HDR_SIZE + pkt_len, GFP_KERNEL);
+	if (!skb)
+		return NULL;
+	skb_reset_transport_header(skb);
+
+	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->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);
+	hdr->size = cpu_to_le32(pkt_len);
+	hdr->dst_node_id = cpu_to_le32(dst_node);
+	hdr->dst_port_id = cpu_to_le32(QRTR_PORT_CTRL);
+
+	buf = (u32 *)skb_put(skb, pkt_len);
+	memset(buf, 0, 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;
+}
+
+static struct qrtr_sock *qrtr_port_lookup(int port);
+static void qrtr_port_put(struct qrtr_sock *ipc);
+
+/* Handle and route a received packet.
+ *
+ * This will auto-reply with resume-tx packet as necessary.
+ */
+static void qrtr_node_rx_work(struct work_struct *work)
+{
+	struct qrtr_node *node = container_of(work, struct qrtr_node, work);
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue(&node->rx_queue)) != NULL) {
+		const struct qrtr_hdr *phdr;
+		u32 dst_node, dst_port;
+		struct qrtr_sock *ipc;
+		u32 src_node;
+		int confirm;
+
+		phdr = (const struct qrtr_hdr *)skb_transport_header(skb);
+		src_node = le32_to_cpu(phdr->src_node_id);
+		dst_node = le32_to_cpu(phdr->dst_node_id);
+		dst_port = le32_to_cpu(phdr->dst_port_id);
+		confirm = !!phdr->confirm_rx;
+
+		qrtr_node_assign(node, src_node);
+
+		ipc = qrtr_port_lookup(dst_port);
+		if (!ipc) {
+			kfree_skb(skb);
+		} else {
+			if (sock_queue_rcv_skb(&ipc->sk, skb))
+				kfree_skb(skb);
+
+			qrtr_port_put(ipc);
+		}
+
+		if (confirm) {
+			skb = qrtr_alloc_resume_tx(dst_node, node->nid, dst_port);
+			if (!skb)
+				break;
+			if (qrtr_node_enqueue(node, skb))
+				break;
+		}
+	}
+}
+
+/**
+ * qrtr_endpoint_register() - register a new endpoint
+ * @ep: endpoint to register
+ * @nid: desired node id; may be QRTR_EP_NID_AUTO for auto-assignment
+ * Return: 0 on success; negative error code on failure
+ *
+ * The specified endpoint must have the xmit function pointer set on call.
+ */
+int qrtr_endpoint_register(struct qrtr_endpoint *ep, unsigned int nid)
+{
+	struct qrtr_node *node;
+
+	if (!ep || !ep->xmit)
+		return -EINVAL;
+
+	node = kzalloc(sizeof(*node), GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+
+	INIT_WORK(&node->work, qrtr_node_rx_work);
+	kref_init(&node->ref);
+	mutex_init(&node->ep_lock);
+	skb_queue_head_init(&node->rx_queue);
+	node->nid = QRTR_EP_NID_AUTO;
+	node->ep = ep;
+
+	qrtr_node_assign(node, nid);
+
+	mutex_lock(&qrtr_node_lock);
+	list_add(&node->item, &qrtr_all_nodes);
+	mutex_unlock(&qrtr_node_lock);
+	ep->node = node;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qrtr_endpoint_register);
+
+/**
+ * qrtr_endpoint_unregister - unregister endpoint
+ * @ep: endpoint to unregister
+ */
+void qrtr_endpoint_unregister(struct qrtr_endpoint *ep)
+{
+	struct qrtr_node *node = ep->node;
+
+	mutex_lock(&node->ep_lock);
+	node->ep = NULL;
+	mutex_unlock(&node->ep_lock);
+
+	qrtr_node_release(node);
+	ep->node = NULL;
+}
+EXPORT_SYMBOL_GPL(qrtr_endpoint_unregister);
+
+/* Lookup socket by port.
+ *
+ * Callers must release with qrtr_port_put()
+ */
+static struct qrtr_sock *qrtr_port_lookup(int port)
+{
+	struct qrtr_sock *ipc;
+
+	if (port == QRTR_PORT_CTRL)
+		port = 0;
+
+	mutex_lock(&qrtr_port_lock);
+	ipc = idr_find(&qrtr_ports, port);
+	if (ipc)
+		sock_hold(&ipc->sk);
+	mutex_unlock(&qrtr_port_lock);
+
+	return ipc;
+}
+
+/* Release acquired socket. */
+static void qrtr_port_put(struct qrtr_sock *ipc)
+{
+	sock_put(&ipc->sk);
+}
+
+/* Remove port assignment. */
+static void qrtr_port_remove(struct qrtr_sock *ipc)
+{
+	int port = ipc->us.sq_port;
+
+	if (port == QRTR_PORT_CTRL)
+		port = 0;
+
+	__sock_put(&ipc->sk);
+
+	mutex_lock(&qrtr_port_lock);
+	idr_remove(&qrtr_ports, port);
+	mutex_unlock(&qrtr_port_lock);
+}
+
+/* Assign port number to socket.
+ *
+ * Specify port in the integer pointed to by port, and it will be adjusted
+ * on return as necesssary.
+ *
+ * Port may be:
+ *   0: Assign ephemeral port in [QRTR_MIN_EPH_SOCKET, QRTR_MAX_EPH_SOCKET]
+ *   <QRTR_MIN_EPH_SOCKET: Specified; requires CAP_NET_ADMIN
+ *   >QRTR_MIN_EPH_SOCKET: Specified; available to all
+ */
+static int qrtr_port_assign(struct qrtr_sock *ipc, int *port)
+{
+	int rc;
+
+	mutex_lock(&qrtr_port_lock);
+	if (!*port) {
+		rc = idr_alloc(&qrtr_ports, ipc,
+			       QRTR_MIN_EPH_SOCKET, QRTR_MAX_EPH_SOCKET + 1,
+			       GFP_ATOMIC);
+		if (rc >= 0)
+			*port = rc;
+	} else if (*port < QRTR_MIN_EPH_SOCKET && !capable(CAP_NET_ADMIN)) {
+		rc = -EACCES;
+	} else if (*port == QRTR_PORT_CTRL) {
+		rc = idr_alloc(&qrtr_ports, ipc, 0, 1, GFP_ATOMIC);
+	} else {
+		rc = idr_alloc(&qrtr_ports, ipc, *port, *port + 1, GFP_ATOMIC);
+		if (rc >= 0)
+			*port = rc;
+	}
+	mutex_unlock(&qrtr_port_lock);
+
+	if (rc == -ENOSPC)
+		return -EADDRINUSE;
+	else if (rc < 0)
+		return rc;
+
+	sock_hold(&ipc->sk);
+
+	return 0;
+}
+
+/* Bind socket to address.
+ *
+ * Socket should be locked upon call.
+ */
+static int __qrtr_bind(struct socket *sock,
+		       const struct sockaddr_qrtr *addr, int zapped)
+{
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	int port;
+	int rc;
+
+	/* rebinding ok */
+	if (!zapped && addr->sq_port == ipc->us.sq_port)
+		return 0;
+
+	port = addr->sq_port;
+	rc = qrtr_port_assign(ipc, &port);
+	if (rc)
+		return rc;
+
+	/* unbind previous, if any */
+	if (!zapped)
+		qrtr_port_remove(ipc);
+	ipc->us.sq_port = port;
+
+	sock_reset_flag(sk, SOCK_ZAPPED);
+
+	return 0;
+}
+
+/* Auto bind to an ephemeral port. */
+static int qrtr_autobind(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct sockaddr_qrtr addr;
+
+	if (!sock_flag(sk, SOCK_ZAPPED))
+		return 0;
+
+	addr.sq_family = AF_QIPCRTR;
+	addr.sq_node = qrtr_local_nid;
+	addr.sq_port = 0;
+
+	return __qrtr_bind(sock, &addr, 1);
+}
+
+/* Bind socket to specified sockaddr. */
+static int qrtr_bind(struct socket *sock, struct sockaddr *saddr, int len)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, saddr);
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	int rc;
+
+	if (len < sizeof(*addr) || addr->sq_family != AF_QIPCRTR)
+		return -EINVAL;
+
+	if (addr->sq_node != ipc->us.sq_node)
+		return -EINVAL;
+
+	lock_sock(sk);
+	rc = __qrtr_bind(sock, addr, sock_flag(sk, SOCK_ZAPPED));
+	release_sock(sk);
+
+	return rc;
+}
+
+/* Queue packet to local peer socket. */
+static int qrtr_local_enqueue(struct qrtr_node *node, struct sk_buff *skb)
+{
+	const struct qrtr_hdr *phdr;
+	struct qrtr_sock *ipc;
+
+	phdr = (const struct qrtr_hdr *)skb_transport_header(skb);
+
+	ipc = qrtr_port_lookup(le32_to_cpu(phdr->dst_port_id));
+	if (!ipc || &ipc->sk == skb->sk) { /* do not send to self */
+		kfree_skb(skb);
+		return -ENODEV;
+	}
+
+	if (sock_queue_rcv_skb(&ipc->sk, skb)) {
+		qrtr_port_put(ipc);
+		kfree_skb(skb);
+		return -ENOSPC;
+	}
+
+	qrtr_port_put(ipc);
+
+	return 0;
+}
+
+/* Queue packet for broadcast. */
+static int qrtr_bcast_enqueue(struct qrtr_node *node, struct sk_buff *skb)
+{
+	struct sk_buff *skbn;
+
+	mutex_lock(&qrtr_node_lock);
+	list_for_each_entry(node, &qrtr_all_nodes, item) {
+		skbn = skb_clone(skb, GFP_KERNEL);
+		if (!skbn)
+			break;
+		skb_set_owner_w(skbn, skb->sk);
+		qrtr_node_enqueue(node, skbn);
+	}
+	mutex_unlock(&qrtr_node_lock);
+
+	qrtr_local_enqueue(node, skb);
+
+	return 0;
+}
+
+static int qrtr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, msg->msg_name);
+	int (*enqueue_fn)(struct qrtr_node *, struct sk_buff *);
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	struct qrtr_node *node;
+	struct qrtr_hdr *hdr;
+	struct sk_buff *skb;
+	size_t plen;
+	int rc;
+
+	if (msg->msg_flags & ~(MSG_DONTWAIT))
+		return -EINVAL;
+
+	if (len > 65535)
+		return -EMSGSIZE;
+
+	lock_sock(sk);
+
+	if (addr) {
+		if (msg->msg_namelen < sizeof(*addr)) {
+			release_sock(sk);
+			return -EINVAL;
+		}
+
+		if (addr->sq_family != AF_QIPCRTR) {
+			release_sock(sk);
+			return -EINVAL;
+		}
+
+		rc = qrtr_autobind(sock);
+		if (rc) {
+			release_sock(sk);
+			return rc;
+		}
+	} else if (sk->sk_state == TCP_ESTABLISHED) {
+		addr = &ipc->peer;
+	} else {
+		release_sock(sk);
+		return -ENOTCONN;
+	}
+
+	node = NULL;
+	if (addr->sq_node == QRTR_NODE_BCAST) {
+		enqueue_fn = qrtr_bcast_enqueue;
+	} else if (addr->sq_node == ipc->us.sq_node) {
+		enqueue_fn = qrtr_local_enqueue;
+	} else {
+		enqueue_fn = qrtr_node_enqueue;
+		node = qrtr_node_lookup(addr->sq_node);
+		if (!node) {
+			release_sock(sk);
+			return -ECONNRESET;
+		}
+	}
+
+	plen = (len + 3) & ~3;
+	skb = sock_alloc_send_skb(sk, plen + QRTR_HDR_SIZE,
+				  msg->msg_flags & MSG_DONTWAIT, &rc);
+	if (!skb)
+		goto out_node;
+
+	skb_reset_transport_header(skb);
+	skb_put(skb, len + QRTR_HDR_SIZE);
+
+	hdr = (struct qrtr_hdr *)skb_transport_header(skb);
+	hdr->version = cpu_to_le32(QRTR_PROTO_VER);
+	hdr->src_node_id = cpu_to_le32(ipc->us.sq_node);
+	hdr->src_port_id = cpu_to_le32(ipc->us.sq_port);
+	hdr->confirm_rx = cpu_to_le32(0);
+	hdr->size = cpu_to_le32(len);
+	hdr->dst_node_id = cpu_to_le32(addr->sq_node);
+	hdr->dst_port_id = cpu_to_le32(addr->sq_port);
+
+	rc = skb_copy_datagram_from_iter(skb, QRTR_HDR_SIZE,
+					 &msg->msg_iter, len);
+	if (rc) {
+		kfree_skb(skb);
+		goto out_node;
+	}
+
+	if (plen != len) {
+		skb_pad(skb, plen - len);
+		skb_put(skb, plen - len);
+	}
+
+	if (ipc->us.sq_port == QRTR_PORT_CTRL) {
+		if (len < 4) {
+			rc = -EINVAL;
+			kfree_skb(skb);
+			goto out_node;
+		}
+
+		/* control messages already require the type as 'command' */
+		skb_copy_bits(skb, QRTR_HDR_SIZE, &hdr->type, 4);
+	} else {
+		hdr->type = cpu_to_le32(QRTR_TYPE_DATA);
+	}
+
+	rc = enqueue_fn(node, skb);
+	if (rc >= 0)
+		rc = len;
+
+out_node:
+	qrtr_node_release(node);
+	release_sock(sk);
+
+	return rc;
+}
+
+static int qrtr_recvmsg(struct socket *sock, struct msghdr *msg,
+			size_t size, int flags)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, msg->msg_name);
+	const struct qrtr_hdr *phdr;
+	struct sock *sk = sock->sk;
+	struct sk_buff *skb;
+	int copied, rc;
+
+	lock_sock(sk);
+
+	if (sock_flag(sk, SOCK_ZAPPED)) {
+		release_sock(sk);
+		return -EADDRNOTAVAIL;
+	}
+
+	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
+				flags & MSG_DONTWAIT, &rc);
+	if (!skb) {
+		release_sock(sk);
+		return rc;
+	}
+
+	phdr = (const struct qrtr_hdr *)skb_transport_header(skb);
+	copied = le32_to_cpu(phdr->size);
+	if (copied > size) {
+		copied = size;
+		msg->msg_flags |= MSG_TRUNC;
+	}
+
+	rc = skb_copy_datagram_msg(skb, QRTR_HDR_SIZE, msg, copied);
+	if (rc < 0)
+		goto out;
+	rc = copied;
+
+	if (addr) {
+		addr->sq_family = AF_QIPCRTR;
+		addr->sq_node = le32_to_cpu(phdr->src_node_id);
+		addr->sq_port = le32_to_cpu(phdr->src_port_id);
+		msg->msg_namelen = sizeof(*addr);
+	}
+
+out:
+	skb_free_datagram(sk, skb);
+	release_sock(sk);
+
+	return rc;
+}
+
+static int qrtr_connect(struct socket *sock, struct sockaddr *saddr,
+			int len, int flags)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, saddr);
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	int rc;
+
+	if (len < sizeof(*addr) || addr->sq_family != AF_QIPCRTR)
+		return -EINVAL;
+
+	lock_sock(sk);
+
+	sk->sk_state = TCP_CLOSE;
+	sock->state = SS_UNCONNECTED;
+
+	rc = qrtr_autobind(sock);
+	if (rc) {
+		release_sock(sk);
+		return rc;
+	}
+
+	ipc->peer = *addr;
+	sock->state = SS_CONNECTED;
+	sk->sk_state = TCP_ESTABLISHED;
+
+	release_sock(sk);
+
+	return 0;
+}
+
+static int qrtr_getname(struct socket *sock, struct sockaddr *saddr,
+			int *len, int peer)
+{
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sockaddr_qrtr qaddr;
+	struct sock *sk = sock->sk;
+
+	lock_sock(sk);
+	if (peer) {
+		if (sk->sk_state != TCP_ESTABLISHED) {
+			release_sock(sk);
+			return -ENOTCONN;
+		}
+
+		qaddr = ipc->peer;
+	} else {
+		qaddr = ipc->us;
+	}
+	release_sock(sk);
+
+	*len = sizeof(qaddr);
+	qaddr.sq_family = AF_QIPCRTR;
+
+	memcpy(saddr, &qaddr, sizeof(qaddr));
+
+	return 0;
+}
+
+static int qrtr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	struct sockaddr_qrtr *sq;
+	struct sk_buff *skb;
+	struct ifreq ifr;
+	long len = 0;
+	int rc = 0;
+
+	lock_sock(sk);
+
+	switch (cmd) {
+	case TIOCOUTQ:
+		len = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
+		if (len < 0)
+			len = 0;
+		rc = put_user(len, (int __user *)argp);
+		break;
+	case TIOCINQ:
+		skb = skb_peek(&sk->sk_receive_queue);
+		if (skb)
+			len = skb->len - QRTR_HDR_SIZE;
+		rc = put_user(len, (int __user *)argp);
+		break;
+	case SIOCGIFADDR:
+		if (copy_from_user(&ifr, argp, sizeof(ifr))) {
+			rc = -EFAULT;
+			break;
+		}
+
+		sq = (struct sockaddr_qrtr *)&ifr.ifr_addr;
+		*sq = ipc->us;
+		if (copy_to_user(argp, &ifr, sizeof(ifr))) {
+			rc = -EFAULT;
+			break;
+		}
+		break;
+	case SIOCGSTAMP:
+		rc = sock_get_timestamp(sk, argp);
+		break;
+	case SIOCADDRT:
+	case SIOCDELRT:
+	case SIOCSIFADDR:
+	case SIOCGIFDSTADDR:
+	case SIOCSIFDSTADDR:
+	case SIOCGIFBRDADDR:
+	case SIOCSIFBRDADDR:
+	case SIOCGIFNETMASK:
+	case SIOCSIFNETMASK:
+		rc = -EINVAL;
+		break;
+	default:
+		rc = -ENOIOCTLCMD;
+		break;
+	}
+
+	release_sock(sk);
+
+	return rc;
+}
+
+static int qrtr_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct qrtr_sock *ipc;
+
+	if (!sk)
+		return 0;
+
+	lock_sock(sk);
+
+	ipc = qrtr_sk(sk);
+	sk->sk_shutdown = SHUTDOWN_MASK;
+	if (!sock_flag(sk, SOCK_DEAD))
+		sk->sk_state_change(sk);
+
+	sock_set_flag(sk, SOCK_DEAD);
+	sock->sk = NULL;
+
+	if (!sock_flag(sk, SOCK_ZAPPED))
+		qrtr_port_remove(ipc);
+
+	skb_queue_purge(&sk->sk_receive_queue);
+
+	release_sock(sk);
+	sock_put(sk);
+
+	return 0;
+}
+
+static const struct proto_ops qrtr_proto_ops = {
+	.owner		= THIS_MODULE,
+	.family		= AF_QIPCRTR,
+	.bind		= qrtr_bind,
+	.connect	= qrtr_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= sock_no_accept,
+	.listen		= sock_no_listen,
+	.sendmsg	= qrtr_sendmsg,
+	.recvmsg	= qrtr_recvmsg,
+	.getname	= qrtr_getname,
+	.ioctl		= qrtr_ioctl,
+	.poll		= datagram_poll,
+	.shutdown	= sock_no_shutdown,
+	.setsockopt	= sock_no_setsockopt,
+	.getsockopt	= sock_no_getsockopt,
+	.release	= qrtr_release,
+	.mmap		= sock_no_mmap,
+	.sendpage	= sock_no_sendpage,
+};
+
+static struct proto qrtr_proto = {
+	.name		= "QIPCRTR",
+	.owner		= THIS_MODULE,
+	.obj_size	= sizeof(struct qrtr_sock),
+};
+
+static int qrtr_create(struct net *net, struct socket *sock,
+		       int protocol, int kern)
+{
+	struct qrtr_sock *ipc;
+	struct sock *sk;
+
+	if (sock->type != SOCK_DGRAM)
+		return -EPROTOTYPE;
+
+	sk = sk_alloc(net, AF_QIPCRTR, GFP_KERNEL, &qrtr_proto, kern);
+	if (!sk)
+		return -ENOMEM;
+
+	sock_set_flag(sk, SOCK_ZAPPED);
+
+	sock_init_data(sock, sk);
+	sock->ops = &qrtr_proto_ops;
+
+	ipc = qrtr_sk(sk);
+	ipc->us.sq_family = AF_QIPCRTR;
+	ipc->us.sq_node = qrtr_local_nid;
+	ipc->us.sq_port = 0;
+
+	return 0;
+}
+
+static const struct nla_policy qrtr_policy[IFA_MAX + 1] = {
+	[IFA_LOCAL] = { .type = NLA_U32 },
+};
+
+static int qrtr_addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+	struct nlattr *tb[IFA_MAX + 1];
+	struct ifaddrmsg *ifm;
+	int rc;
+
+	if (!netlink_capable(skb, CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (!netlink_capable(skb, CAP_SYS_ADMIN))
+		return -EPERM;
+
+	ASSERT_RTNL();
+
+	rc = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, qrtr_policy);
+	if (rc < 0)
+		return rc;
+
+	ifm = nlmsg_data(nlh);
+	if (!tb[IFA_LOCAL])
+		return -EINVAL;
+
+	qrtr_local_nid = nla_get_u32(tb[IFA_LOCAL]);
+	return 0;
+}
+
+static const struct net_proto_family qrtr_family = {
+	.owner	= THIS_MODULE,
+	.family	= AF_QIPCRTR,
+	.create	= qrtr_create,
+};
+
+static int __init qrtr_proto_init(void)
+{
+	int rc;
+
+	rc = proto_register(&qrtr_proto, 1);
+	if (rc)
+		return rc;
+
+	rc = sock_register(&qrtr_family);
+	if (rc) {
+		proto_unregister(&qrtr_proto);
+		return rc;
+	}
+
+	rtnl_register(PF_QIPCRTR, RTM_NEWADDR, qrtr_addr_doit, NULL, NULL);
+
+	return 0;
+}
+module_init(qrtr_proto_init);
+
+static void __exit qrtr_proto_fini(void)
+{
+	rtnl_unregister(PF_QIPCRTR, RTM_NEWADDR);
+	sock_unregister(qrtr_family.family);
+	proto_unregister(&qrtr_proto);
+}
+module_exit(qrtr_proto_fini);
+
+MODULE_DESCRIPTION("Qualcomm IPC-router driver");
+MODULE_LICENSE("GPL v2");

net/qrtr/qrtr.h

+#ifndef __QRTR_H_
+#define __QRTR_H_
+
+#include <linux/types.h>
+
+struct sk_buff;
+
+/* endpoint node id auto assignment */
+#define QRTR_EP_NID_AUTO (-1)
+
+/**
+ * struct qrtr_endpoint - endpoint handle
+ * @xmit: Callback for outgoing packets
+ *
+ * The socket buffer passed to the xmit function becomes owned by the endpoint
+ * driver.  As such, when the driver is done with the buffer, it should
+ * call kfree_skb() on failure, or consume_skb() on success.
+ */
+struct qrtr_endpoint {
+	int (*xmit)(struct qrtr_endpoint *ep, struct sk_buff *skb);
+	/* private: not for endpoint use */
+	struct qrtr_node *node;
+};
+
+int qrtr_endpoint_register(struct qrtr_endpoint *ep, unsigned int nid);
+
+void qrtr_endpoint_unregister(struct qrtr_endpoint *ep);
+
+int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len);
+
+#endif

net/qrtr/smd.c

+/*
+ * Copyright (c) 2015, Sony Mobile Communications Inc.
+ * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/soc/qcom/smd.h>
+
+#include "qrtr.h"
+
+struct qrtr_smd_dev {
+	struct qrtr_endpoint ep;
+	struct qcom_smd_channel *channel;
+};
+
+/* from smd to qrtr */
+static int qcom_smd_qrtr_callback(struct qcom_smd_device *sdev,
+				  const void *data, size_t len)
+{
+	struct qrtr_smd_dev *qdev = dev_get_drvdata(&sdev->dev);
+	int rc;
+
+	if (!qdev)
+		return -EAGAIN;
+
+	rc = qrtr_endpoint_post(&qdev->ep, data, len);
+	if (rc == -EINVAL) {
+		dev_err(&sdev->dev, "invalid ipcrouter packet\n");
+		/* return 0 to let smd drop the packet */
+		rc = 0;
+	}
+
+	return rc;
+}
+
+/* from qrtr to smd */
+static int qcom_smd_qrtr_send(struct qrtr_endpoint *ep, struct sk_buff *skb)
+{
+	struct qrtr_smd_dev *qdev = container_of(ep, struct qrtr_smd_dev, ep);
+	int rc;
+
+	rc = skb_linearize(skb);
+	if (rc)
+		goto out;
+
+	rc = qcom_smd_send(qdev->channel, skb->data, skb->len);
+
+out:
+	if (rc)
+		kfree_skb(skb);
+	else
+		consume_skb(skb);
+	return rc;
+}
+
+static int qcom_smd_qrtr_probe(struct qcom_smd_device *sdev)
+{
+	struct qrtr_smd_dev *qdev;
+	int rc;
+
+	qdev = devm_kzalloc(&sdev->dev, sizeof(*qdev), GFP_KERNEL);
+	if (!qdev)
+		return -ENOMEM;
+
+	qdev->channel = sdev->channel;
+	qdev->ep.xmit = qcom_smd_qrtr_send;
+
+	rc = qrtr_endpoint_register(&qdev->ep, QRTR_EP_NID_AUTO);
+	if (rc)
+		return rc;
+
+	dev_set_drvdata(&sdev->dev, qdev);
+
+	dev_dbg(&sdev->dev, "Qualcomm SMD QRTR driver probed\n");
+
+	return 0;
+}
+
+static void qcom_smd_qrtr_remove(struct qcom_smd_device *sdev)
+{
+	struct qrtr_smd_dev *qdev = dev_get_drvdata(&sdev->dev);
+
+	qrtr_endpoint_unregister(&qdev->ep);
+
+	dev_set_drvdata(&sdev->dev, NULL);
+}
+
+static const struct qcom_smd_id qcom_smd_qrtr_smd_match[] = {
+	{ "IPCRTR" },
+	{}
+};
+
+static struct qcom_smd_driver qcom_smd_qrtr_driver = {
+	.probe = qcom_smd_qrtr_probe,
+	.remove = qcom_smd_qrtr_remove,
+	.callback = qcom_smd_qrtr_callback,
+	.smd_match_table = qcom_smd_qrtr_smd_match,
+	.driver = {
+		.name = "qcom_smd_qrtr",
+		.owner = THIS_MODULE,
+	},
+};
+
+module_qcom_smd_driver(qcom_smd_qrtr_driver);
+
+MODULE_DESCRIPTION("Qualcomm IPC-Router SMD interface driver");
+MODULE_LICENSE("GPL v2");