can: dev: fix deadlock reported after bus-off

[pandora-kernel.git] / drivers / net / can / dev.c

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 25695bd..a1f434e 100644 (file)
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -22,6 +22,7 @@
 #include <linux/slab.h>
 #include <linux/netdevice.h>
 #include <linux/if_arp.h>
+#include <linux/workqueue.h>
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/netlink.h>
@@ -352,7 +353,7 @@ void can_free_echo_skb(struct net_device *dev, unsigned int idx)
        BUG_ON(idx >= priv->echo_skb_max);
 
        if (priv->echo_skb[idx]) {
-               kfree_skb(priv->echo_skb[idx]);
+               dev_kfree_skb_any(priv->echo_skb[idx]);
                priv->echo_skb[idx] = NULL;
        }
 }
@@ -361,9 +362,8 @@ EXPORT_SYMBOL_GPL(can_free_echo_skb);
 /*
  * CAN device restart for bus-off recovery
  */
-void can_restart(unsigned long data)
+void can_restart(struct net_device *dev)
 {
-       struct net_device *dev = (struct net_device *)data;
        struct can_priv *priv = netdev_priv(dev);
        struct net_device_stats *stats = &dev->stats;
        struct sk_buff *skb;
@@ -403,6 +403,14 @@ restart:
                dev_err(dev->dev.parent, "Error %d during restart", err);
 }
 
+static void can_restart_work(struct work_struct *work)
+{
+       struct delayed_work *dwork = to_delayed_work(work);
+       struct can_priv *priv = container_of(dwork, struct can_priv, restart_work);
+
+       can_restart(priv->dev);
+}
+
 int can_restart_now(struct net_device *dev)
 {
        struct can_priv *priv = netdev_priv(dev);
@@ -416,8 +424,8 @@ int can_restart_now(struct net_device *dev)
        if (priv->state != CAN_STATE_BUS_OFF)
                return -EBUSY;
 
-       /* Runs as soon as possible in the timer context */
-       mod_timer(&priv->restart_timer, jiffies);
+       cancel_delayed_work_sync(&priv->restart_work);
+       can_restart(dev);
 
        return 0;
 }
@@ -439,8 +447,8 @@ void can_bus_off(struct net_device *dev)
        priv->can_stats.bus_off++;
 
        if (priv->restart_ms)
-               mod_timer(&priv->restart_timer,
-                         jiffies + (priv->restart_ms * HZ) / 1000);
+               schedule_delayed_work(&priv->restart_work,
+                                     msecs_to_jiffies(priv->restart_ms));
 }
 EXPORT_SYMBOL_GPL(can_bus_off);
 
@@ -468,6 +476,11 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
        skb->protocol = htons(ETH_P_CAN);
        skb->pkt_type = PACKET_BROADCAST;
        skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+       skb_reset_mac_header(skb);
+       skb_reset_network_header(skb);
+       skb_reset_transport_header(skb);
+
        *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
        memset(*cf, 0, sizeof(struct can_frame));
 
@@ -510,6 +523,7 @@ struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
                return NULL;
 
        priv = netdev_priv(dev);
+       priv->dev = dev;
 
        if (echo_skb_max) {
                priv->echo_skb_max = echo_skb_max;
@@ -519,7 +533,7 @@ struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
 
        priv->state = CAN_STATE_STOPPED;
 
-       init_timer(&priv->restart_timer);
+       INIT_DELAYED_WORK(&priv->restart_work, can_restart_work);
 
        return dev;
 }
@@ -553,8 +567,6 @@ int open_candev(struct net_device *dev)
        if (!netif_carrier_ok(dev))
                netif_carrier_on(dev);
 
-       setup_timer(&priv->restart_timer, can_restart, (unsigned long)dev);
-
        return 0;
 }
 EXPORT_SYMBOL_GPL(open_candev);
@@ -569,8 +581,7 @@ void close_candev(struct net_device *dev)
 {
        struct can_priv *priv = netdev_priv(dev);
 
-       if (del_timer_sync(&priv->restart_timer))
-               dev_put(dev);
+       cancel_delayed_work_sync(&priv->restart_work);
        can_flush_echo_skb(dev);
 }
 EXPORT_SYMBOL_GPL(close_candev);
@@ -606,10 +617,14 @@ static int can_changelink(struct net_device *dev,
                if (dev->flags & IFF_UP)
                        return -EBUSY;
                cm = nla_data(data[IFLA_CAN_CTRLMODE]);
-               if (cm->flags & ~priv->ctrlmode_supported)
+
+               /* check whether changed bits are allowed to be modified */
+               if (cm->mask & ~priv->ctrlmode_supported)
                        return -EOPNOTSUPP;
+
+               /* clear bits to be modified and copy the flag values */
                priv->ctrlmode &= ~cm->mask;
-               priv->ctrlmode |= cm->flags;
+               priv->ctrlmode |= (cm->flags & cm->mask);
        }
 
        if (data[IFLA_CAN_BITTIMING]) {
@@ -659,14 +674,14 @@ static size_t can_get_size(const struct net_device *dev)
        size_t size;
 
        size = nla_total_size(sizeof(u32));   /* IFLA_CAN_STATE */
-       size += sizeof(struct can_ctrlmode);  /* IFLA_CAN_CTRLMODE */
+       size += nla_total_size(sizeof(struct can_ctrlmode));  /* IFLA_CAN_CTRLMODE */
        size += nla_total_size(sizeof(u32));  /* IFLA_CAN_RESTART_MS */
-       size += sizeof(struct can_bittiming); /* IFLA_CAN_BITTIMING */
-       size += sizeof(struct can_clock);     /* IFLA_CAN_CLOCK */
+       size += nla_total_size(sizeof(struct can_bittiming)); /* IFLA_CAN_BITTIMING */
+       size += nla_total_size(sizeof(struct can_clock));     /* IFLA_CAN_CLOCK */
        if (priv->do_get_berr_counter)        /* IFLA_CAN_BERR_COUNTER */
-               size += sizeof(struct can_berr_counter);
+               size += nla_total_size(sizeof(struct can_berr_counter));
        if (priv->bittiming_const)            /* IFLA_CAN_BITTIMING_CONST */
-               size += sizeof(struct can_bittiming_const);
+               size += nla_total_size(sizeof(struct can_bittiming_const));
 
        return size;
 }
@@ -685,7 +700,7 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
        NLA_PUT_U32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms);
        NLA_PUT(skb, IFLA_CAN_BITTIMING,
                sizeof(priv->bittiming), &priv->bittiming);
-       NLA_PUT(skb, IFLA_CAN_CLOCK, sizeof(cm), &priv->clock);
+       NLA_PUT(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock);
        if (priv->do_get_berr_counter && !priv->do_get_berr_counter(dev, &bec))
                NLA_PUT(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec);
        if (priv->bittiming_const)
@@ -722,6 +737,11 @@ static int can_newlink(struct net *src_net, struct net_device *dev,
        return -EOPNOTSUPP;
 }
 
+static void can_dellink(struct net_device *dev, struct list_head *head)
+{
+       return;
+}
+
 static struct rtnl_link_ops can_link_ops __read_mostly = {
        .kind           = "can",
        .maxtype        = IFLA_CAN_MAX,
@@ -729,6 +749,7 @@ static struct rtnl_link_ops can_link_ops __read_mostly = {
        .setup          = can_setup,
        .newlink        = can_newlink,
        .changelink     = can_changelink,
+       .dellink        = can_dellink,
        .get_size       = can_get_size,
        .fill_info      = can_fill_info,
        .get_xstats_size = can_get_xstats_size,