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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/caif/chnl_net.c
Initial import
Diffstat (limited to 'net/caif/chnl_net.c')
-rw-r--r--net/caif/chnl_net.c552
1 files changed, 552 insertions, 0 deletions
diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
new file mode 100644
index 000000000..67a4a36fe
--- /dev/null
+++ b/net/caif/chnl_net.c
@@ -0,0 +1,552 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Authors: Sjur Brendeland
+ * Daniel Martensson
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
+
+#include <linux/fs.h>
+#include <linux/hardirq.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/if_ether.h>
+#include <linux/moduleparam.h>
+#include <linux/ip.h>
+#include <linux/sched.h>
+#include <linux/sockios.h>
+#include <linux/caif/if_caif.h>
+#include <net/rtnetlink.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/caif_dev.h>
+
+/* GPRS PDP connection has MTU to 1500 */
+#define GPRS_PDP_MTU 1500
+/* 5 sec. connect timeout */
+#define CONNECT_TIMEOUT (5 * HZ)
+#define CAIF_NET_DEFAULT_QUEUE_LEN 500
+#define UNDEF_CONNID 0xffffffff
+
+/*This list is protected by the rtnl lock. */
+static LIST_HEAD(chnl_net_list);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_RTNL_LINK("caif");
+
+enum caif_states {
+ CAIF_CONNECTED = 1,
+ CAIF_CONNECTING,
+ CAIF_DISCONNECTED,
+ CAIF_SHUTDOWN
+};
+
+struct chnl_net {
+ struct cflayer chnl;
+ struct net_device_stats stats;
+ struct caif_connect_request conn_req;
+ struct list_head list_field;
+ struct net_device *netdev;
+ char name[256];
+ wait_queue_head_t netmgmt_wq;
+ /* Flow status to remember and control the transmission. */
+ bool flowenabled;
+ enum caif_states state;
+};
+
+static void robust_list_del(struct list_head *delete_node)
+{
+ struct list_head *list_node;
+ struct list_head *n;
+ ASSERT_RTNL();
+ list_for_each_safe(list_node, n, &chnl_net_list) {
+ if (list_node == delete_node) {
+ list_del(list_node);
+ return;
+ }
+ }
+ WARN_ON(1);
+}
+
+static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
+{
+ struct sk_buff *skb;
+ struct chnl_net *priv;
+ int pktlen;
+ const u8 *ip_version;
+ u8 buf;
+
+ priv = container_of(layr, struct chnl_net, chnl);
+ if (!priv)
+ return -EINVAL;
+
+ skb = (struct sk_buff *) cfpkt_tonative(pkt);
+
+ /* Get length of CAIF packet. */
+ pktlen = skb->len;
+
+ /* Pass some minimum information and
+ * send the packet to the net stack.
+ */
+ skb->dev = priv->netdev;
+
+ /* check the version of IP */
+ ip_version = skb_header_pointer(skb, 0, 1, &buf);
+ if (!ip_version) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ switch (*ip_version >> 4) {
+ case 4:
+ skb->protocol = htons(ETH_P_IP);
+ break;
+ case 6:
+ skb->protocol = htons(ETH_P_IPV6);
+ break;
+ default:
+ kfree_skb(skb);
+ priv->netdev->stats.rx_errors++;
+ return -EINVAL;
+ }
+
+ /* If we change the header in loop mode, the checksum is corrupted. */
+ if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ else
+ skb->ip_summed = CHECKSUM_NONE;
+
+ if (in_interrupt())
+ netif_rx(skb);
+ else
+ netif_rx_ni(skb);
+
+ /* Update statistics. */
+ priv->netdev->stats.rx_packets++;
+ priv->netdev->stats.rx_bytes += pktlen;
+
+ return 0;
+}
+
+static int delete_device(struct chnl_net *dev)
+{
+ ASSERT_RTNL();
+ if (dev->netdev)
+ unregister_netdevice(dev->netdev);
+ return 0;
+}
+
+static void close_work(struct work_struct *work)
+{
+ struct chnl_net *dev = NULL;
+ struct list_head *list_node;
+ struct list_head *_tmp;
+
+ rtnl_lock();
+ list_for_each_safe(list_node, _tmp, &chnl_net_list) {
+ dev = list_entry(list_node, struct chnl_net, list_field);
+ if (dev->state == CAIF_SHUTDOWN)
+ dev_close(dev->netdev);
+ }
+ rtnl_unlock();
+}
+static DECLARE_WORK(close_worker, close_work);
+
+static void chnl_hold(struct cflayer *lyr)
+{
+ struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
+ dev_hold(priv->netdev);
+}
+
+static void chnl_put(struct cflayer *lyr)
+{
+ struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
+ dev_put(priv->netdev);
+}
+
+static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
+ int phyid)
+{
+ struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
+ pr_debug("NET flowctrl func called flow: %s\n",
+ flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
+ flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
+ flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
+ flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
+ flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
+ flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
+ "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND");
+
+
+
+ switch (flow) {
+ case CAIF_CTRLCMD_FLOW_OFF_IND:
+ priv->flowenabled = false;
+ netif_stop_queue(priv->netdev);
+ break;
+ case CAIF_CTRLCMD_DEINIT_RSP:
+ priv->state = CAIF_DISCONNECTED;
+ break;
+ case CAIF_CTRLCMD_INIT_FAIL_RSP:
+ priv->state = CAIF_DISCONNECTED;
+ wake_up_interruptible(&priv->netmgmt_wq);
+ break;
+ case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
+ priv->state = CAIF_SHUTDOWN;
+ netif_tx_disable(priv->netdev);
+ schedule_work(&close_worker);
+ break;
+ case CAIF_CTRLCMD_FLOW_ON_IND:
+ priv->flowenabled = true;
+ netif_wake_queue(priv->netdev);
+ break;
+ case CAIF_CTRLCMD_INIT_RSP:
+ caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
+ priv->state = CAIF_CONNECTED;
+ priv->flowenabled = true;
+ netif_wake_queue(priv->netdev);
+ wake_up_interruptible(&priv->netmgmt_wq);
+ break;
+ default:
+ break;
+ }
+}
+
+static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct chnl_net *priv;
+ struct cfpkt *pkt = NULL;
+ int len;
+ int result = -1;
+ /* Get our private data. */
+ priv = netdev_priv(dev);
+
+ if (skb->len > priv->netdev->mtu) {
+ pr_warn("Size of skb exceeded MTU\n");
+ kfree_skb(skb);
+ dev->stats.tx_errors++;
+ return NETDEV_TX_OK;
+ }
+
+ if (!priv->flowenabled) {
+ pr_debug("dropping packets flow off\n");
+ kfree_skb(skb);
+ dev->stats.tx_dropped++;
+ return NETDEV_TX_OK;
+ }
+
+ if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
+ swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
+
+ /* Store original SKB length. */
+ len = skb->len;
+
+ pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
+
+ /* Send the packet down the stack. */
+ result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
+ if (result) {
+ dev->stats.tx_dropped++;
+ return NETDEV_TX_OK;
+ }
+
+ /* Update statistics. */
+ dev->stats.tx_packets++;
+ dev->stats.tx_bytes += len;
+
+ return NETDEV_TX_OK;
+}
+
+static int chnl_net_open(struct net_device *dev)
+{
+ struct chnl_net *priv = NULL;
+ int result = -1;
+ int llifindex, headroom, tailroom, mtu;
+ struct net_device *lldev;
+ ASSERT_RTNL();
+ priv = netdev_priv(dev);
+ if (!priv) {
+ pr_debug("chnl_net_open: no priv\n");
+ return -ENODEV;
+ }
+
+ if (priv->state != CAIF_CONNECTING) {
+ priv->state = CAIF_CONNECTING;
+ result = caif_connect_client(dev_net(dev), &priv->conn_req,
+ &priv->chnl, &llifindex,
+ &headroom, &tailroom);
+ if (result != 0) {
+ pr_debug("err: "
+ "Unable to register and open device,"
+ " Err:%d\n",
+ result);
+ goto error;
+ }
+
+ lldev = __dev_get_by_index(dev_net(dev), llifindex);
+
+ if (lldev == NULL) {
+ pr_debug("no interface?\n");
+ result = -ENODEV;
+ goto error;
+ }
+
+ dev->needed_tailroom = tailroom + lldev->needed_tailroom;
+ dev->hard_header_len = headroom + lldev->hard_header_len +
+ lldev->needed_tailroom;
+
+ /*
+ * MTU, head-room etc is not know before we have a
+ * CAIF link layer device available. MTU calculation may
+ * override initial RTNL configuration.
+ * MTU is minimum of current mtu, link layer mtu pluss
+ * CAIF head and tail, and PDP GPRS contexts max MTU.
+ */
+ mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
+ mtu = min_t(int, GPRS_PDP_MTU, mtu);
+ dev_set_mtu(dev, mtu);
+
+ if (mtu < 100) {
+ pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
+ result = -ENODEV;
+ goto error;
+ }
+ }
+
+ rtnl_unlock(); /* Release RTNL lock during connect wait */
+
+ result = wait_event_interruptible_timeout(priv->netmgmt_wq,
+ priv->state != CAIF_CONNECTING,
+ CONNECT_TIMEOUT);
+
+ rtnl_lock();
+
+ if (result == -ERESTARTSYS) {
+ pr_debug("wait_event_interruptible woken by a signal\n");
+ result = -ERESTARTSYS;
+ goto error;
+ }
+
+ if (result == 0) {
+ pr_debug("connect timeout\n");
+ caif_disconnect_client(dev_net(dev), &priv->chnl);
+ priv->state = CAIF_DISCONNECTED;
+ pr_debug("state disconnected\n");
+ result = -ETIMEDOUT;
+ goto error;
+ }
+
+ if (priv->state != CAIF_CONNECTED) {
+ pr_debug("connect failed\n");
+ result = -ECONNREFUSED;
+ goto error;
+ }
+ pr_debug("CAIF Netdevice connected\n");
+ return 0;
+
+error:
+ caif_disconnect_client(dev_net(dev), &priv->chnl);
+ priv->state = CAIF_DISCONNECTED;
+ pr_debug("state disconnected\n");
+ return result;
+
+}
+
+static int chnl_net_stop(struct net_device *dev)
+{
+ struct chnl_net *priv;
+
+ ASSERT_RTNL();
+ priv = netdev_priv(dev);
+ priv->state = CAIF_DISCONNECTED;
+ caif_disconnect_client(dev_net(dev), &priv->chnl);
+ return 0;
+}
+
+static int chnl_net_init(struct net_device *dev)
+{
+ struct chnl_net *priv;
+ ASSERT_RTNL();
+ priv = netdev_priv(dev);
+ strncpy(priv->name, dev->name, sizeof(priv->name));
+ return 0;
+}
+
+static void chnl_net_uninit(struct net_device *dev)
+{
+ struct chnl_net *priv;
+ ASSERT_RTNL();
+ priv = netdev_priv(dev);
+ robust_list_del(&priv->list_field);
+}
+
+static const struct net_device_ops netdev_ops = {
+ .ndo_open = chnl_net_open,
+ .ndo_stop = chnl_net_stop,
+ .ndo_init = chnl_net_init,
+ .ndo_uninit = chnl_net_uninit,
+ .ndo_start_xmit = chnl_net_start_xmit,
+};
+
+static void chnl_net_destructor(struct net_device *dev)
+{
+ struct chnl_net *priv = netdev_priv(dev);
+ caif_free_client(&priv->chnl);
+ free_netdev(dev);
+}
+
+static void ipcaif_net_setup(struct net_device *dev)
+{
+ struct chnl_net *priv;
+ dev->netdev_ops = &netdev_ops;
+ dev->destructor = chnl_net_destructor;
+ dev->flags |= IFF_NOARP;
+ dev->flags |= IFF_POINTOPOINT;
+ dev->mtu = GPRS_PDP_MTU;
+ dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
+
+ priv = netdev_priv(dev);
+ priv->chnl.receive = chnl_recv_cb;
+ priv->chnl.ctrlcmd = chnl_flowctrl_cb;
+ priv->netdev = dev;
+ priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
+ priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
+ priv->conn_req.priority = CAIF_PRIO_LOW;
+ /* Insert illegal value */
+ priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
+ priv->flowenabled = false;
+
+ init_waitqueue_head(&priv->netmgmt_wq);
+}
+
+
+static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+ struct chnl_net *priv;
+ u8 loop;
+ priv = netdev_priv(dev);
+ if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
+ priv->conn_req.sockaddr.u.dgm.connection_id) ||
+ nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
+ priv->conn_req.sockaddr.u.dgm.connection_id))
+ goto nla_put_failure;
+ loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
+ if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
+ goto nla_put_failure;
+ return 0;
+nla_put_failure:
+ return -EMSGSIZE;
+
+}
+
+static void caif_netlink_parms(struct nlattr *data[],
+ struct caif_connect_request *conn_req)
+{
+ if (!data) {
+ pr_warn("no params data found\n");
+ return;
+ }
+ if (data[IFLA_CAIF_IPV4_CONNID])
+ conn_req->sockaddr.u.dgm.connection_id =
+ nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
+ if (data[IFLA_CAIF_IPV6_CONNID])
+ conn_req->sockaddr.u.dgm.connection_id =
+ nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
+ if (data[IFLA_CAIF_LOOPBACK]) {
+ if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
+ conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
+ else
+ conn_req->protocol = CAIFPROTO_DATAGRAM;
+ }
+}
+
+static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[])
+{
+ int ret;
+ struct chnl_net *caifdev;
+ ASSERT_RTNL();
+ caifdev = netdev_priv(dev);
+ caif_netlink_parms(data, &caifdev->conn_req);
+
+ ret = register_netdevice(dev);
+ if (ret)
+ pr_warn("device rtml registration failed\n");
+ else
+ list_add(&caifdev->list_field, &chnl_net_list);
+
+ /* Use ifindex as connection id, and use loopback channel default. */
+ if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
+ caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
+ caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
+ }
+ return ret;
+}
+
+static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
+ struct nlattr *data[])
+{
+ struct chnl_net *caifdev;
+ ASSERT_RTNL();
+ caifdev = netdev_priv(dev);
+ caif_netlink_parms(data, &caifdev->conn_req);
+ netdev_state_change(dev);
+ return 0;
+}
+
+static size_t ipcaif_get_size(const struct net_device *dev)
+{
+ return
+ /* IFLA_CAIF_IPV4_CONNID */
+ nla_total_size(4) +
+ /* IFLA_CAIF_IPV6_CONNID */
+ nla_total_size(4) +
+ /* IFLA_CAIF_LOOPBACK */
+ nla_total_size(2) +
+ 0;
+}
+
+static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
+ [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
+ [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
+ [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
+};
+
+
+static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
+ .kind = "caif",
+ .priv_size = sizeof(struct chnl_net),
+ .setup = ipcaif_net_setup,
+ .maxtype = IFLA_CAIF_MAX,
+ .policy = ipcaif_policy,
+ .newlink = ipcaif_newlink,
+ .changelink = ipcaif_changelink,
+ .get_size = ipcaif_get_size,
+ .fill_info = ipcaif_fill_info,
+
+};
+
+static int __init chnl_init_module(void)
+{
+ return rtnl_link_register(&ipcaif_link_ops);
+}
+
+static void __exit chnl_exit_module(void)
+{
+ struct chnl_net *dev = NULL;
+ struct list_head *list_node;
+ struct list_head *_tmp;
+ rtnl_link_unregister(&ipcaif_link_ops);
+ rtnl_lock();
+ list_for_each_safe(list_node, _tmp, &chnl_net_list) {
+ dev = list_entry(list_node, struct chnl_net, list_field);
+ list_del(list_node);
+ delete_device(dev);
+ }
+ rtnl_unlock();
+}
+
+module_init(chnl_init_module);
+module_exit(chnl_exit_module);