2015-12-11 20:42:09

by Bjorn Andersson

[permalink] [raw]
Subject: [PATCH] net: add Qualcomm IPC router

From: Courtney Cavin <[email protected]>

Add an implementation of Qualcomm's IPC router protocol, used to
communicate with service providing remote processors.

Signed-off-by: Courtney Cavin <[email protected]>
---

Downstream this code also includes a large part of a service discovery
mechanism, controlled through a set of custom ioctls. This functionality is
instead moved to user space, a reference implementation for this can be found
at:

https://github.com/sonyxperiadev/qrtr

include/linux/socket.h | 4 +-
include/uapi/linux/qrtr.h | 12 +
net/Kconfig | 1 +
net/Makefile | 1 +
net/qrtr/Kconfig | 24 ++
net/qrtr/Makefile | 2 +
net/qrtr/qrtr.c | 976 ++++++++++++++++++++++++++++++++++++++++++++++
net/qrtr/qrtr.h | 31 ++
net/qrtr/smd.c | 119 ++++++
9 files changed, 1169 insertions(+), 1 deletion(-)
create mode 100644 include/uapi/linux/qrtr.h
create mode 100644 net/qrtr/Kconfig
create mode 100644 net/qrtr/Makefile
create mode 100644 net/qrtr/qrtr.c
create mode 100644 net/qrtr/qrtr.h
create mode 100644 net/qrtr/smd.c

diff --git a/include/linux/socket.h b/include/linux/socket.h
index 5bf59c8493b7..10e600db06f1 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -200,7 +200,8 @@ struct ucred {
#define AF_ALG 38 /* Algorithm sockets */
#define AF_NFC 39 /* NFC sockets */
#define AF_VSOCK 40 /* vSockets */
-#define AF_MAX 41 /* For now.. */
+#define AF_QIPCRTR 41 /* Qualcomm IPC Router */
+#define AF_MAX 42 /* For now.. */

/* Protocol families, same as address families. */
#define PF_UNSPEC AF_UNSPEC
@@ -246,6 +247,7 @@ struct ucred {
#define PF_ALG AF_ALG
#define PF_NFC AF_NFC
#define PF_VSOCK AF_VSOCK
+#define PF_QIPCRTR AF_QIPCRTR
#define PF_MAX AF_MAX

/* Maximum queue length specifiable by listen. */
diff --git a/include/uapi/linux/qrtr.h b/include/uapi/linux/qrtr.h
new file mode 100644
index 000000000000..66c0748d26e2
--- /dev/null
+++ b/include/uapi/linux/qrtr.h
@@ -0,0 +1,12 @@
+#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 */
diff --git a/net/Kconfig b/net/Kconfig
index 11f8c22af34d..5d9a52ef9a55 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -233,6 +233,7 @@ source "net/mpls/Kconfig"
source "net/hsr/Kconfig"
source "net/switchdev/Kconfig"
source "net/l3mdev/Kconfig"
+source "net/qrtr/Kconfig"

config RPS
bool
diff --git a/net/Makefile b/net/Makefile
index a5d04098dfce..007deb2f17c2 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -77,3 +77,4 @@ endif
ifneq ($(CONFIG_NET_L3_MASTER_DEV),)
obj-y += l3mdev/
endif
+obj-$(CONFIG_QRTR) += qrtr/
diff --git a/net/qrtr/Kconfig b/net/qrtr/Kconfig
new file mode 100644
index 000000000000..f053cc25f621
--- /dev/null
+++ b/net/qrtr/Kconfig
@@ -0,0 +1,24 @@
+# Qualcomm IPC Router configuration
+#
+
+config QRTR
+ bool "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 QRTR && QCOM_SMD && OF
+ ---help---
+ Say Y here to support SMD based ipcrouter channels. SMD is the
+ most common transport for IPC Router.
+
+endif # QRTR
diff --git a/net/qrtr/Makefile b/net/qrtr/Makefile
new file mode 100644
index 000000000000..e282a84ffc5c
--- /dev/null
+++ b/net/qrtr/Makefile
@@ -0,0 +1,2 @@
+obj-y := qrtr.o
+obj-$(CONFIG_QRTR_SMD) += smd.o
diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c
new file mode 100644
index 000000000000..c96dfb6bfbaf
--- /dev/null
+++ b/net/qrtr/qrtr.c
@@ -0,0 +1,976 @@
+/*
+ * 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/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;
+module_param_named(node_id, qrtr_local_nid, uint, S_IRUGO);
+MODULE_PARM_DESC(idVendor, "Local Node Identifier");
+
+/* 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;
+
+ if (src_node != 0)
+ 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 = 0;
+ 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 != 0 && 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 == 0 || 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 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;
+ }
+
+ return 0;
+}
+module_init(qrtr_proto_init);
+
+static void __exit qrtr_proto_fini(void)
+{
+ sock_unregister(qrtr_family.family);
+ proto_unregister(&qrtr_proto);
+}
+module_exit(qrtr_proto_fini);
+
+MODULE_DESCRIPTION("Qualcomm IPC-router driver");
+MODULE_LICENSE("GPL v2");
diff --git a/net/qrtr/qrtr.h b/net/qrtr/qrtr.h
new file mode 100644
index 000000000000..2b848718f8fe
--- /dev/null
+++ b/net/qrtr/qrtr.h
@@ -0,0 +1,31 @@
+#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
diff --git a/net/qrtr/smd.c b/net/qrtr/smd.c
new file mode 100644
index 000000000000..c980f117821f
--- /dev/null
+++ b/net/qrtr/smd.c
@@ -0,0 +1,119 @@
+/*
+ * 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) { /* we're probably still probing */
+ dev_warn(&sdev->dev, "callback called early; postponing\n");
+ 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");
--
2.4.2


2015-12-15 21:01:18

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] net: add Qualcomm IPC router

From: Bjorn Andersson <[email protected]>
Date: Fri, 11 Dec 2015 12:41:59 -0800

> +static unsigned int qrtr_local_nid = 1;
> +module_param_named(node_id, qrtr_local_nid, uint, S_IRUGO);
> +MODULE_PARM_DESC(idVendor, "Local Node Identifier");

Module parameters suck.

Allow the user to choose this dynamically. You have roughtly two choices.

1) Subvert the 'protocol' field passed to ->create() and use that, it is
being ignored otherwise.

2) Put it into the socket address for bind().

2015-12-15 21:13:32

by Dan Williams

[permalink] [raw]
Subject: Re: [PATCH] net: add Qualcomm IPC router

On Tue, 2015-12-15 at 16:01 -0500, David Miller wrote:
> From: Bjorn Andersson <[email protected]>
> Date: Fri, 11 Dec 2015 12:41:59 -0800
>
> > +static unsigned int qrtr_local_nid = 1;
> > +module_param_named(node_id, qrtr_local_nid, uint, S_IRUGO);
> > +MODULE_PARM_DESC(idVendor, "Local Node Identifier");

Also s/idVendor/node_id?

Dan

> Module parameters suck.
>
> Allow the user to choose this dynamically. You have roughtly two
> choices.
>
> 1) Subvert the 'protocol' field passed to ->create() and use that, it
> is
> being ignored otherwise.
>
> 2) Put it into the socket address for bind().
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html

2015-12-15 21:14:14

by Dan Williams

[permalink] [raw]
Subject: Re: [PATCH] net: add Qualcomm IPC router

On Tue, 2015-12-15 at 15:13 -0600, Dan Williams wrote:
> On Tue, 2015-12-15 at 16:01 -0500, David Miller wrote:
> > From: Bjorn Andersson <[email protected]>
> > Date: Fri, 11 Dec 2015 12:41:59 -0800
> >
> > > +static unsigned int qrtr_local_nid = 1;
> > > +module_param_named(node_id, qrtr_local_nid, uint, S_IRUGO);
> > > +MODULE_PARM_DESC(idVendor, "Local Node Identifier");
>
> Also s/idVendor/node_id?

Well, not that it matters if the module parameter gets removed...

Dan

>
> Dan
>
> > Module parameters suck.
> >
> > Allow the user to choose this dynamically. You have roughtly two
> > choices.
> >
> > 1) Subvert the 'protocol' field passed to ->create() and use that,
> > it
> > is
> > being ignored otherwise.
> >
> > 2) Put it into the socket address for bind().
> > --
> > To unsubscribe from this list: send the line "unsubscribe netdev"
> > in
> > the body of a message to [email protected]
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html

2015-12-16 23:39:06

by Courtney Cavin

[permalink] [raw]
Subject: Re: [PATCH] net: add Qualcomm IPC router

On Fri, Dec 11, 2015 at 09:41:59PM +0100, Bjorn Andersson wrote:
> From: Courtney Cavin <[email protected]>
>
> Add an implementation of Qualcomm's IPC router protocol, used to
> communicate with service providing remote processors.
>
> Signed-off-by: Courtney Cavin <[email protected]>
> ---
[...]
> +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 == 0 || addr->sq_node == ipc->us.sq_node) {

'addr->sq_node == 0' should be removed from this if-condition. Zero is
a valid node id. Clients needing the local address can use
getsockname(2).

> + 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;
> + }
> + }

-Courtney

2015-12-17 00:01:53

by Courtney Cavin

[permalink] [raw]
Subject: Re: [PATCH] net: add Qualcomm IPC router

On Tue, Dec 15, 2015 at 10:01:14PM +0100, David Miller wrote:
> From: Bjorn Andersson <[email protected]>
> Date: Fri, 11 Dec 2015 12:41:59 -0800
>
> > +static unsigned int qrtr_local_nid = 1;
> > +module_param_named(node_id, qrtr_local_nid, uint, S_IRUGO);
> > +MODULE_PARM_DESC(idVendor, "Local Node Identifier");
>
> Module parameters suck.
>
> Allow the user to choose this dynamically. You have roughtly two choices.
>
> 1) Subvert the 'protocol' field passed to ->create() and use that, it is
> being ignored otherwise.
>
> 2) Put it into the socket address for bind().

So each socket can have its own node id? That doesn't seem right.

The way these node ids are assigned is by a system designer (in this
case Qualcomm). The ARM, Linux CPU is always node 1, the audio DSP is
always node 5, etc. Anyone with the knowhow could reassign these
numbers, but there's no reason to have them be dynamic during runtime.
Additionally, allowing dynamic assignment would require code to prevent
id duplication for known remote nodes, as well as to deal with cases in
which remote node discovery happens after local sockets have acquired
that node's id.

Maybe the first socket created needs CAP_NET_ADMIN, and uses the
'protocol' field to set the node id? Ugh. Gross.

We could hardcode the value in kconfig, but that seems like a worse
solution than a module parameter.

I'm open to further suggestions.

-Courtney

2015-12-17 00:16:51

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] net: add Qualcomm IPC router

From: Courtney Cavin <[email protected]>
Date: Wed, 16 Dec 2015 16:01:41 -0800

> We could hardcode the value in kconfig, but that seems like a worse
> solution than a module parameter.
>
> I'm open to further suggestions.

No module parameters, configure it via netlink or similar at run
time.