summaryrefslogtreecommitdiffstats
path: root/net/can/af_can.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/can/af_can.c')
-rw-r--r--net/can/af_can.c124
1 files changed, 40 insertions, 84 deletions
diff --git a/net/can/af_can.c b/net/can/af_can.c
index 51adc4c..702be5a 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -77,8 +77,8 @@ static int stats_timer __read_mostly = 1;
module_param(stats_timer, int, S_IRUGO);
MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
-HLIST_HEAD(can_rx_dev_list);
-static struct dev_rcv_lists can_rx_alldev_list;
+/* receive filters subscribed for 'all' CAN devices */
+struct dev_rcv_lists can_rx_alldev_list;
static DEFINE_SPINLOCK(can_rcvlists_lock);
static struct kmem_cache *rcv_cache __read_mostly;
@@ -292,28 +292,10 @@ EXPORT_SYMBOL(can_send);
static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
{
- struct dev_rcv_lists *d = NULL;
- struct hlist_node *n;
-
- /*
- * find receive list for this device
- *
- * The hlist_for_each_entry*() macros curse through the list
- * using the pointer variable n and set d to the containing
- * struct in each list iteration. Therefore, after list
- * iteration, d is unmodified when the list is empty, and it
- * points to last list element, when the list is non-empty
- * but no match in the loop body is found. I.e. d is *not*
- * NULL when no match is found. We can, however, use the
- * cursor variable n to decide if a match was found.
- */
-
- hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
- if (d->dev == dev)
- break;
- }
-
- return n ? d : NULL;
+ if (!dev)
+ return &can_rx_alldev_list;
+ else
+ return (struct dev_rcv_lists *)dev->ml_priv;
}
/**
@@ -433,6 +415,9 @@ int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
/* insert new receiver (dev,canid,mask) -> (func,data) */
+ if (dev && dev->type != ARPHRD_CAN)
+ return -ENODEV;
+
r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
if (!r)
return -ENOMEM;
@@ -468,16 +453,6 @@ int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
EXPORT_SYMBOL(can_rx_register);
/*
- * can_rx_delete_device - rcu callback for dev_rcv_lists structure removal
- */
-static void can_rx_delete_device(struct rcu_head *rp)
-{
- struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
-
- kfree(d);
-}
-
-/*
* can_rx_delete_receiver - rcu callback for single receiver entry removal
*/
static void can_rx_delete_receiver(struct rcu_head *rp)
@@ -506,6 +481,9 @@ void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
struct hlist_node *next;
struct dev_rcv_lists *d;
+ if (dev && dev->type != ARPHRD_CAN)
+ return;
+
spin_lock(&can_rcvlists_lock);
d = find_dev_rcv_lists(dev);
@@ -541,7 +519,6 @@ void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
"dev %s, id %03X, mask %03X\n",
DNAME(dev), can_id, mask);
r = NULL;
- d = NULL;
goto out;
}
@@ -552,10 +529,10 @@ void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
can_pstats.rcv_entries--;
/* remove device structure requested by NETDEV_UNREGISTER */
- if (d->remove_on_zero_entries && !d->entries)
- hlist_del_rcu(&d->list);
- else
- d = NULL;
+ if (d->remove_on_zero_entries && !d->entries) {
+ kfree(d);
+ dev->ml_priv = NULL;
+ }
out:
spin_unlock(&can_rcvlists_lock);
@@ -563,10 +540,6 @@ void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
/* schedule the receiver item for deletion */
if (r)
call_rcu(&r->rcu, can_rx_delete_receiver);
-
- /* schedule the device structure for deletion */
- if (d)
- call_rcu(&d->rcu, can_rx_delete_device);
}
EXPORT_SYMBOL(can_rx_unregister);
@@ -780,48 +753,35 @@ static int can_notifier(struct notifier_block *nb, unsigned long msg,
case NETDEV_REGISTER:
- /*
- * create new dev_rcv_lists for this device
- *
- * N.B. zeroing the struct is the correct initialization
- * for the embedded hlist_head structs.
- * Another list type, e.g. list_head, would require
- * explicit initialization.
- */
-
+ /* create new dev_rcv_lists for this device */
d = kzalloc(sizeof(*d), GFP_KERNEL);
if (!d) {
printk(KERN_ERR
"can: allocation of receive list failed\n");
return NOTIFY_DONE;
}
- d->dev = dev;
-
- spin_lock(&can_rcvlists_lock);
- hlist_add_head_rcu(&d->list, &can_rx_dev_list);
- spin_unlock(&can_rcvlists_lock);
+ BUG_ON(dev->ml_priv);
+ dev->ml_priv = d;
break;
case NETDEV_UNREGISTER:
spin_lock(&can_rcvlists_lock);
- d = find_dev_rcv_lists(dev);
+ d = dev->ml_priv;
if (d) {
- if (d->entries) {
+ if (d->entries)
d->remove_on_zero_entries = 1;
- d = NULL;
- } else
- hlist_del_rcu(&d->list);
+ else {
+ kfree(d);
+ dev->ml_priv = NULL;
+ }
} else
printk(KERN_ERR "can: notifier: receive list not "
"found for dev %s\n", dev->name);
spin_unlock(&can_rcvlists_lock);
- if (d)
- call_rcu(&d->rcu, can_rx_delete_device);
-
break;
}
@@ -853,21 +813,13 @@ static __init int can_init(void)
{
printk(banner);
+ memset(&can_rx_alldev_list, 0, sizeof(can_rx_alldev_list));
+
rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
0, 0, NULL);
if (!rcv_cache)
return -ENOMEM;
- /*
- * Insert can_rx_alldev_list for reception on all devices.
- * This struct is zero initialized which is correct for the
- * embedded hlist heads, the dev pointer, and the entries counter.
- */
-
- spin_lock(&can_rcvlists_lock);
- hlist_add_head_rcu(&can_rx_alldev_list.list, &can_rx_dev_list);
- spin_unlock(&can_rcvlists_lock);
-
if (stats_timer) {
/* the statistics are updated every second (timer triggered) */
setup_timer(&can_stattimer, can_stat_update, 0);
@@ -887,8 +839,7 @@ static __init int can_init(void)
static __exit void can_exit(void)
{
- struct dev_rcv_lists *d;
- struct hlist_node *n, *next;
+ struct net_device *dev;
if (stats_timer)
del_timer(&can_stattimer);
@@ -900,14 +851,19 @@ static __exit void can_exit(void)
unregister_netdevice_notifier(&can_netdev_notifier);
sock_unregister(PF_CAN);
- /* remove can_rx_dev_list */
- spin_lock(&can_rcvlists_lock);
- hlist_del(&can_rx_alldev_list.list);
- hlist_for_each_entry_safe(d, n, next, &can_rx_dev_list, list) {
- hlist_del(&d->list);
- kfree(d);
+ /* remove created dev_rcv_lists from still registered CAN devices */
+ rcu_read_lock();
+ for_each_netdev_rcu(&init_net, dev) {
+ if (dev->type == ARPHRD_CAN && dev->ml_priv){
+
+ struct dev_rcv_lists *d = dev->ml_priv;
+
+ BUG_ON(d->entries);
+ kfree(d);
+ dev->ml_priv = NULL;
+ }
}
- spin_unlock(&can_rcvlists_lock);
+ rcu_read_unlock();
rcu_barrier(); /* Wait for completion of call_rcu()'s */
OpenPOWER on IntegriCloud