| /* |
| * CAIF Interface registration. |
| * Copyright (C) ST-Ericsson AB 2010 |
| * Author: Sjur Brendeland/sjur.brandeland@stericsson.com |
| * License terms: GNU General Public License (GPL) version 2 |
| * |
| * Borrowed heavily from file: pn_dev.c. Thanks to |
| * Remi Denis-Courmont <remi.denis-courmont@nokia.com> |
| * and Sakari Ailus <sakari.ailus@nokia.com> |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__ |
| |
| #include <linux/version.h> |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/if_arp.h> |
| #include <linux/net.h> |
| #include <linux/netdevice.h> |
| #include <linux/skbuff.h> |
| #include <linux/sched.h> |
| #include <linux/wait.h> |
| #include <net/netns/generic.h> |
| #include <net/net_namespace.h> |
| #include <net/pkt_sched.h> |
| #include <net/caif/caif_device.h> |
| #include <net/caif/caif_dev.h> |
| #include <net/caif/caif_layer.h> |
| #include <net/caif/cfpkt.h> |
| #include <net/caif/cfcnfg.h> |
| |
| MODULE_LICENSE("GPL"); |
| #define TIMEOUT (HZ*5) |
| |
| /* Used for local tracking of the CAIF net devices */ |
| struct caif_device_entry { |
| struct cflayer layer; |
| struct list_head list; |
| atomic_t in_use; |
| atomic_t state; |
| u16 phyid; |
| struct net_device *netdev; |
| wait_queue_head_t event; |
| }; |
| |
| struct caif_device_entry_list { |
| struct list_head list; |
| /* Protects simulanous deletes in list */ |
| spinlock_t lock; |
| }; |
| |
| struct caif_net { |
| struct caif_device_entry_list caifdevs; |
| }; |
| |
| static int caif_net_id; |
| static struct cfcnfg *cfg; |
| |
| static struct caif_device_entry_list *caif_device_list(struct net *net) |
| { |
| struct caif_net *caifn; |
| BUG_ON(!net); |
| caifn = net_generic(net, caif_net_id); |
| BUG_ON(!caifn); |
| return &caifn->caifdevs; |
| } |
| |
| /* Allocate new CAIF device. */ |
| static struct caif_device_entry *caif_device_alloc(struct net_device *dev) |
| { |
| struct caif_device_entry_list *caifdevs; |
| struct caif_device_entry *caifd; |
| caifdevs = caif_device_list(dev_net(dev)); |
| BUG_ON(!caifdevs); |
| caifd = kzalloc(sizeof(*caifd), GFP_ATOMIC); |
| if (!caifd) |
| return NULL; |
| caifd->netdev = dev; |
| list_add(&caifd->list, &caifdevs->list); |
| init_waitqueue_head(&caifd->event); |
| return caifd; |
| } |
| |
| static struct caif_device_entry *caif_get(struct net_device *dev) |
| { |
| struct caif_device_entry_list *caifdevs = |
| caif_device_list(dev_net(dev)); |
| struct caif_device_entry *caifd; |
| BUG_ON(!caifdevs); |
| list_for_each_entry(caifd, &caifdevs->list, list) { |
| if (caifd->netdev == dev) |
| return caifd; |
| } |
| return NULL; |
| } |
| |
| static void caif_device_destroy(struct net_device *dev) |
| { |
| struct caif_device_entry_list *caifdevs = |
| caif_device_list(dev_net(dev)); |
| struct caif_device_entry *caifd; |
| ASSERT_RTNL(); |
| if (dev->type != ARPHRD_CAIF) |
| return; |
| |
| spin_lock_bh(&caifdevs->lock); |
| caifd = caif_get(dev); |
| if (caifd == NULL) { |
| spin_unlock_bh(&caifdevs->lock); |
| return; |
| } |
| |
| list_del(&caifd->list); |
| spin_unlock_bh(&caifdevs->lock); |
| |
| kfree(caifd); |
| } |
| |
| static int transmit(struct cflayer *layer, struct cfpkt *pkt) |
| { |
| struct caif_device_entry *caifd = |
| container_of(layer, struct caif_device_entry, layer); |
| struct sk_buff *skb, *skb2; |
| int ret = -EINVAL; |
| skb = cfpkt_tonative(pkt); |
| skb->dev = caifd->netdev; |
| /* |
| * Don't allow SKB to be destroyed upon error, but signal resend |
| * notification to clients. We can't rely on the return value as |
| * congestion (NET_XMIT_CN) sometimes drops the packet, sometimes don't. |
| */ |
| if (netif_queue_stopped(caifd->netdev)) |
| return -EAGAIN; |
| skb2 = skb_get(skb); |
| |
| ret = dev_queue_xmit(skb2); |
| |
| if (!ret) |
| kfree_skb(skb); |
| else |
| return -EAGAIN; |
| |
| return 0; |
| } |
| |
| static int modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl) |
| { |
| struct caif_device_entry *caifd; |
| struct caif_dev_common *caifdev; |
| caifd = container_of(layr, struct caif_device_entry, layer); |
| caifdev = netdev_priv(caifd->netdev); |
| if (ctrl == _CAIF_MODEMCMD_PHYIF_USEFULL) { |
| atomic_set(&caifd->in_use, 1); |
| wake_up_interruptible(&caifd->event); |
| |
| } else if (ctrl == _CAIF_MODEMCMD_PHYIF_USELESS) { |
| atomic_set(&caifd->in_use, 0); |
| wake_up_interruptible(&caifd->event); |
| } |
| return 0; |
| } |
| |
| /* |
| * Stuff received packets to associated sockets. |
| * On error, returns non-zero and releases the skb. |
| */ |
| static int receive(struct sk_buff *skb, struct net_device *dev, |
| struct packet_type *pkttype, struct net_device *orig_dev) |
| { |
| struct net *net; |
| struct cfpkt *pkt; |
| struct caif_device_entry *caifd; |
| net = dev_net(dev); |
| pkt = cfpkt_fromnative(CAIF_DIR_IN, skb); |
| caifd = caif_get(dev); |
| if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) |
| return NET_RX_DROP; |
| |
| if (caifd->layer.up->receive(caifd->layer.up, pkt)) |
| return NET_RX_DROP; |
| |
| return 0; |
| } |
| |
| static struct packet_type caif_packet_type __read_mostly = { |
| .type = cpu_to_be16(ETH_P_CAIF), |
| .func = receive, |
| }; |
| |
| static void dev_flowctrl(struct net_device *dev, int on) |
| { |
| struct caif_device_entry *caifd = caif_get(dev); |
| if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) |
| return; |
| |
| caifd->layer.up->ctrlcmd(caifd->layer.up, |
| on ? |
| _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND : |
| _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND, |
| caifd->layer.id); |
| } |
| |
| /* notify Caif of device events */ |
| static int caif_device_notify(struct notifier_block *me, unsigned long what, |
| void *arg) |
| { |
| struct net_device *dev = arg; |
| struct caif_device_entry *caifd = NULL; |
| struct caif_dev_common *caifdev; |
| enum cfcnfg_phy_preference pref; |
| int res = -EINVAL; |
| enum cfcnfg_phy_type phy_type; |
| |
| if (dev->type != ARPHRD_CAIF) |
| return 0; |
| |
| switch (what) { |
| case NETDEV_REGISTER: |
| netdev_info(dev, "register\n"); |
| caifd = caif_device_alloc(dev); |
| if (caifd == NULL) |
| break; |
| caifdev = netdev_priv(dev); |
| caifdev->flowctrl = dev_flowctrl; |
| atomic_set(&caifd->state, what); |
| res = 0; |
| break; |
| |
| case NETDEV_UP: |
| netdev_info(dev, "up\n"); |
| caifd = caif_get(dev); |
| if (caifd == NULL) |
| break; |
| caifdev = netdev_priv(dev); |
| if (atomic_read(&caifd->state) == NETDEV_UP) { |
| netdev_info(dev, "already up\n"); |
| break; |
| } |
| atomic_set(&caifd->state, what); |
| caifd->layer.transmit = transmit; |
| caifd->layer.modemcmd = modemcmd; |
| |
| if (caifdev->use_frag) |
| phy_type = CFPHYTYPE_FRAG; |
| else |
| phy_type = CFPHYTYPE_CAIF; |
| |
| switch (caifdev->link_select) { |
| case CAIF_LINK_HIGH_BANDW: |
| pref = CFPHYPREF_HIGH_BW; |
| break; |
| case CAIF_LINK_LOW_LATENCY: |
| pref = CFPHYPREF_LOW_LAT; |
| break; |
| default: |
| pref = CFPHYPREF_HIGH_BW; |
| break; |
| } |
| dev_hold(dev); |
| cfcnfg_add_phy_layer(get_caif_conf(), |
| phy_type, |
| dev, |
| &caifd->layer, |
| &caifd->phyid, |
| pref, |
| caifdev->use_fcs, |
| caifdev->use_stx); |
| strncpy(caifd->layer.name, dev->name, |
| sizeof(caifd->layer.name) - 1); |
| caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0; |
| break; |
| |
| case NETDEV_GOING_DOWN: |
| caifd = caif_get(dev); |
| if (caifd == NULL) |
| break; |
| netdev_info(dev, "going down\n"); |
| |
| if (atomic_read(&caifd->state) == NETDEV_GOING_DOWN || |
| atomic_read(&caifd->state) == NETDEV_DOWN) |
| break; |
| |
| atomic_set(&caifd->state, what); |
| if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) |
| return -EINVAL; |
| caifd->layer.up->ctrlcmd(caifd->layer.up, |
| _CAIF_CTRLCMD_PHYIF_DOWN_IND, |
| caifd->layer.id); |
| might_sleep(); |
| res = wait_event_interruptible_timeout(caifd->event, |
| atomic_read(&caifd->in_use) == 0, |
| TIMEOUT); |
| break; |
| |
| case NETDEV_DOWN: |
| caifd = caif_get(dev); |
| if (caifd == NULL) |
| break; |
| netdev_info(dev, "down\n"); |
| if (atomic_read(&caifd->in_use)) |
| netdev_warn(dev, |
| "Unregistering an active CAIF device\n"); |
| cfcnfg_del_phy_layer(get_caif_conf(), &caifd->layer); |
| dev_put(dev); |
| atomic_set(&caifd->state, what); |
| break; |
| |
| case NETDEV_UNREGISTER: |
| caifd = caif_get(dev); |
| netdev_info(dev, "unregister\n"); |
| atomic_set(&caifd->state, what); |
| caif_device_destroy(dev); |
| break; |
| } |
| return 0; |
| } |
| |
| static struct notifier_block caif_device_notifier = { |
| .notifier_call = caif_device_notify, |
| .priority = 0, |
| }; |
| |
| |
| struct cfcnfg *get_caif_conf(void) |
| { |
| return cfg; |
| } |
| EXPORT_SYMBOL(get_caif_conf); |
| |
| int caif_connect_client(struct caif_connect_request *conn_req, |
| struct cflayer *client_layer, int *ifindex, |
| int *headroom, int *tailroom) |
| { |
| struct cfctrl_link_param param; |
| int ret; |
| ret = connect_req_to_link_param(get_caif_conf(), conn_req, ¶m); |
| if (ret) |
| return ret; |
| /* Hook up the adaptation layer. */ |
| return cfcnfg_add_adaptation_layer(get_caif_conf(), ¶m, |
| client_layer, ifindex, |
| headroom, tailroom); |
| } |
| EXPORT_SYMBOL(caif_connect_client); |
| |
| int caif_disconnect_client(struct cflayer *adap_layer) |
| { |
| return cfcnfg_disconn_adapt_layer(get_caif_conf(), adap_layer); |
| } |
| EXPORT_SYMBOL(caif_disconnect_client); |
| |
| void caif_release_client(struct cflayer *adap_layer) |
| { |
| cfcnfg_release_adap_layer(adap_layer); |
| } |
| EXPORT_SYMBOL(caif_release_client); |
| |
| /* Per-namespace Caif devices handling */ |
| static int caif_init_net(struct net *net) |
| { |
| struct caif_net *caifn = net_generic(net, caif_net_id); |
| INIT_LIST_HEAD(&caifn->caifdevs.list); |
| spin_lock_init(&caifn->caifdevs.lock); |
| return 0; |
| } |
| |
| static void caif_exit_net(struct net *net) |
| { |
| struct net_device *dev; |
| int res; |
| rtnl_lock(); |
| for_each_netdev(net, dev) { |
| if (dev->type != ARPHRD_CAIF) |
| continue; |
| res = dev_close(dev); |
| caif_device_destroy(dev); |
| } |
| rtnl_unlock(); |
| } |
| |
| static struct pernet_operations caif_net_ops = { |
| .init = caif_init_net, |
| .exit = caif_exit_net, |
| .id = &caif_net_id, |
| .size = sizeof(struct caif_net), |
| }; |
| |
| /* Initialize Caif devices list */ |
| static int __init caif_device_init(void) |
| { |
| int result; |
| cfg = cfcnfg_create(); |
| if (!cfg) { |
| pr_warn("can't create cfcnfg\n"); |
| goto err_cfcnfg_create_failed; |
| } |
| result = register_pernet_device(&caif_net_ops); |
| |
| if (result) { |
| kfree(cfg); |
| cfg = NULL; |
| return result; |
| } |
| dev_add_pack(&caif_packet_type); |
| register_netdevice_notifier(&caif_device_notifier); |
| |
| return result; |
| err_cfcnfg_create_failed: |
| return -ENODEV; |
| } |
| |
| static void __exit caif_device_exit(void) |
| { |
| dev_remove_pack(&caif_packet_type); |
| unregister_pernet_device(&caif_net_ops); |
| unregister_netdevice_notifier(&caif_device_notifier); |
| cfcnfg_remove(cfg); |
| } |
| |
| module_init(caif_device_init); |
| module_exit(caif_device_exit); |