diff options
| -rw-r--r-- | include/net/caif/cfcnfg.h | 10 | ||||
| -rw-r--r-- | net/caif/caif_dev.c | 277 |
2 files changed, 169 insertions, 118 deletions
diff --git a/include/net/caif/cfcnfg.h b/include/net/caif/cfcnfg.h index f33d3634113..e0a1eb5d7ea 100644 --- a/include/net/caif/cfcnfg.h +++ b/include/net/caif/cfcnfg.h @@ -145,4 +145,14 @@ struct dev_info *cfcnfg_get_phyid(struct cfcnfg *cnfg, * @ifi: ifindex obtained from socket.c bindtodevice. */ int cfcnfg_get_id_from_ifi(struct cfcnfg *cnfg, int ifi); + +/** + * cfcnfg_set_phy_state() - Set the state of the physical interface device. + * @cnfg: Configuration object + * @phy_layer: Physical Layer representation + * @up: State of device + */ +int cfcnfg_set_phy_state(struct cfcnfg *cnfg, struct cflayer *phy_layer, + bool up); + #endif /* CFCNFG_H_ */ diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c index 75e00d59eb4..6d1d86be187 100644 --- a/net/caif/caif_dev.c +++ b/net/caif/caif_dev.c @@ -12,14 +12,11 @@ #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 <linux/mutex.h> #include <net/netns/generic.h> #include <net/net_namespace.h> #include <net/pkt_sched.h> @@ -30,23 +27,19 @@ #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; + int __percpu *pcpu_refcnt; }; struct caif_device_entry_list { struct list_head list; /* Protects simulanous deletes in list */ - spinlock_t lock; + struct mutex lock; }; struct caif_net { @@ -65,19 +58,39 @@ static struct caif_device_entry_list *caif_device_list(struct net *net) return &caifn->caifdevs; } +static void caifd_put(struct caif_device_entry *e) +{ + irqsafe_cpu_dec(*e->pcpu_refcnt); +} + +static void caifd_hold(struct caif_device_entry *e) +{ + irqsafe_cpu_inc(*e->pcpu_refcnt); +} + +static int caifd_refcnt_read(struct caif_device_entry *e) +{ + int i, refcnt = 0; + for_each_possible_cpu(i) + refcnt += *per_cpu_ptr(e->pcpu_refcnt, i); + return refcnt; +} + /* 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->pcpu_refcnt = alloc_percpu(int); caifd->netdev = dev; - list_add(&caifd->list, &caifdevs->list); - init_waitqueue_head(&caifd->event); + dev_hold(dev); return caifd; } @@ -87,35 +100,13 @@ static struct caif_device_entry *caif_get(struct net_device *dev) caif_device_list(dev_net(dev)); struct caif_device_entry *caifd; BUG_ON(!caifdevs); - list_for_each_entry(caifd, &caifdevs->list, list) { + list_for_each_entry_rcu(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 = @@ -130,23 +121,8 @@ static int transmit(struct cflayer *layer, struct cfpkt *pkt) return 0; } -static int modemcmd(struct cflayer *layr, enum caif_modemcmd ctrl) -{ - struct caif_device_entry *caifd; - caifd = container_of(layr, struct caif_device_entry, layer); - 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. + * Stuff received packets into the CAIF stack. * On error, returns non-zero and releases the skb. */ static int receive(struct sk_buff *skb, struct net_device *dev, @@ -154,14 +130,27 @@ static int receive(struct sk_buff *skb, struct net_device *dev, { struct cfpkt *pkt; struct caif_device_entry *caifd; + pkt = cfpkt_fromnative(CAIF_DIR_IN, skb); + + rcu_read_lock(); caifd = caif_get(dev); - if (!caifd || !caifd->layer.up || !caifd->layer.up->receive) - return NET_RX_DROP; - if (caifd->layer.up->receive(caifd->layer.up, pkt)) + if (!caifd || !caifd->layer.up || !caifd->layer.up->receive || + !netif_oper_up(caifd->netdev)) { + rcu_read_unlock(); + kfree_skb(skb); return NET_RX_DROP; + } + + /* Hold reference to netdevice while using CAIF stack */ + caifd_hold(caifd); + rcu_read_unlock(); + caifd->layer.up->receive(caifd->layer.up, pkt); + + /* Release reference to stack upwards */ + caifd_put(caifd); return 0; } @@ -172,15 +161,25 @@ static struct packet_type caif_packet_type __read_mostly = { 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) + struct caif_device_entry *caifd; + + rcu_read_lock(); + + caifd = caif_get(dev); + if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) { + rcu_read_unlock(); return; + } + + caifd_hold(caifd); + rcu_read_unlock(); caifd->layer.up->ctrlcmd(caifd->layer.up, on ? _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND : _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND, caifd->layer.id); + caifd_put(caifd); } /* notify Caif of device events */ @@ -192,34 +191,22 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what, struct caif_dev_common *caifdev; enum cfcnfg_phy_preference pref; enum cfcnfg_phy_type phy_type; + struct caif_device_entry_list *caifdevs = + caif_device_list(dev_net(dev)); 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; + if (!caifd) + return 0; + caifdev = netdev_priv(dev); caifdev->flowctrl = dev_flowctrl; - atomic_set(&caifd->state, what); - 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; @@ -237,62 +224,95 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what, pref = CFPHYPREF_HIGH_BW; break; } - dev_hold(dev); + strncpy(caifd->layer.name, dev->name, + sizeof(caifd->layer.name) - 1); + caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0; + + mutex_lock(&caifdevs->lock); + list_add_rcu(&caifd->list, &caifdevs->list); + cfcnfg_add_phy_layer(cfg, phy_type, dev, &caifd->layer, - &caifd->phyid, + 0, 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; + mutex_unlock(&caifdevs->lock); break; - case NETDEV_GOING_DOWN: + case NETDEV_UP: + rcu_read_lock(); + caifd = caif_get(dev); - if (caifd == NULL) + if (caifd == NULL) { + rcu_read_unlock(); break; - netdev_info(dev, "going down\n"); + } - if (atomic_read(&caifd->state) == NETDEV_GOING_DOWN || - atomic_read(&caifd->state) == NETDEV_DOWN) - break; + cfcnfg_set_phy_state(cfg, &caifd->layer, true); + rcu_read_unlock(); - 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(); - wait_event_interruptible_timeout(caifd->event, - atomic_read(&caifd->in_use) == 0, - TIMEOUT); break; case NETDEV_DOWN: + rcu_read_lock(); + 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(cfg, &caifd->layer); - dev_put(dev); - atomic_set(&caifd->state, what); + if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd) { + rcu_read_unlock(); + return -EINVAL; + } + + cfcnfg_set_phy_state(cfg, &caifd->layer, false); + caifd_hold(caifd); + rcu_read_unlock(); + + caifd->layer.up->ctrlcmd(caifd->layer.up, + _CAIF_CTRLCMD_PHYIF_DOWN_IND, + caifd->layer.id); + caifd_put(caifd); break; case NETDEV_UNREGISTER: + mutex_lock(&caifdevs->lock); + caifd = caif_get(dev); - if (caifd == NULL) + if (caifd == NULL) { + mutex_unlock(&caifdevs->lock); break; - netdev_info(dev, "unregister\n"); - atomic_set(&caifd->state, what); - caif_device_destroy(dev); + } + list_del_rcu(&caifd->list); + + /* + * NETDEV_UNREGISTER is called repeatedly until all reference + * counts for the net-device are released. If references to + * caifd is taken, simply ignore NETDEV_UNREGISTER and wait for + * the next call to NETDEV_UNREGISTER. + * + * If any packets are in flight down the CAIF Stack, + * cfcnfg_del_phy_layer will return nonzero. + * If no packets are in flight, the CAIF Stack associated + * with the net-device un-registering is freed. + */ + + if (caifd_refcnt_read(caifd) != 0 || + cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0) { + + pr_info("Wait for device inuse\n"); + /* Enrole device if CAIF Stack is still in use */ + list_add_rcu(&caifd->list, &caifdevs->list); + mutex_unlock(&caifdevs->lock); + break; + } + + synchronize_rcu(); + dev_put(caifd->netdev); + free_percpu(caifd->pcpu_refcnt); + kfree(caifd); + + mutex_unlock(&caifdevs->lock); break; } return 0; @@ -304,8 +324,8 @@ static struct notifier_block caif_device_notifier = { }; int caif_connect_client(struct caif_connect_request *conn_req, - struct cflayer *client_layer, int *ifindex, - int *headroom, int *tailroom) + struct cflayer *client_layer, int *ifindex, + int *headroom, int *tailroom) { struct cfctrl_link_param param; int ret; @@ -315,8 +335,8 @@ int caif_connect_client(struct caif_connect_request *conn_req, return ret; /* Hook up the adaptation layer. */ return cfcnfg_add_adaptation_layer(cfg, ¶m, - client_layer, ifindex, - headroom, tailroom); + client_layer, ifindex, + headroom, tailroom); } EXPORT_SYMBOL(caif_connect_client); @@ -331,20 +351,40 @@ 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); + mutex_init(&caifn->caifdevs.lock); return 0; } static void caif_exit_net(struct net *net) { - struct net_device *dev; + struct caif_device_entry *caifd, *tmp; + struct caif_device_entry_list *caifdevs = + caif_device_list(net); + rtnl_lock(); - for_each_netdev(net, dev) { - if (dev->type != ARPHRD_CAIF) - continue; - dev_close(dev); - caif_device_destroy(dev); + mutex_lock(&caifdevs->lock); + + list_for_each_entry_safe(caifd, tmp, &caifdevs->list, list) { + int i = 0; + list_del_rcu(&caifd->list); + cfcnfg_set_phy_state(cfg, &caifd->layer, false); + + while (i < 10 && + (caifd_refcnt_read(caifd) != 0 || + cfcnfg_del_phy_layer(cfg, &caifd->layer) != 0)) { + + pr_info("Wait for device inuse\n"); + msleep(250); + i++; + } + synchronize_rcu(); + dev_put(caifd->netdev); + free_percpu(caifd->pcpu_refcnt); + kfree(caifd); } + + + mutex_unlock(&caifdevs->lock); rtnl_unlock(); } @@ -359,6 +399,7 @@ static struct pernet_operations caif_net_ops = { static int __init caif_device_init(void) { int result; + cfg = cfcnfg_create(); if (!cfg) { pr_warn("can't create cfcnfg\n"); |