From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
This patch removes the old method of allocating the per device protocol
specific memory via a netdevice_notifier. This had the drawback, that
the allocation can fail, leading to a lot of null pointer checks in the
code. This also makes the live cycle management of this memory quite
complicated.
This patch switches from the allocating the struct can_dev_rcv_lists in
a NETDEV_REGISTER call to using the dev->ml_priv, which is allocated by
the driver since the previous patch.
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
drivers/net/can/dev.c | 2 ++
drivers/net/can/slcan.c | 1 +
drivers/net/can/vcan.c | 1 +
drivers/net/can/vxcan.c | 1 +
net/can/af_can.c | 44 +++++++----------------------------------
net/can/af_can.h | 1 -
6 files changed, 12 insertions(+), 38 deletions(-)
diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index d89d76199d23..bd75afdaf163 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -736,6 +736,8 @@ struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
priv = netdev_priv(dev);
priv->dev = dev;
+ dev->ml_priv = (void *)priv + ALIGN(sizeof_priv, NETDEV_ALIGN);
+
if (echo_skb_max) {
priv->echo_skb_max = echo_skb_max;
priv->echo_skb = (void *)priv +
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index 5b2e95425e69..bb6032211043 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -536,6 +536,7 @@ static struct slcan *slc_alloc(void)
dev->base_addr = i;
sl = netdev_priv(dev);
+ dev->ml_priv = (void *)sl + ALIGN(sizeof(*sl), NETDEV_ALIGN);
/* Initialize channel control data */
sl->magic = SLCAN_MAGIC;
diff --git a/drivers/net/can/vcan.c b/drivers/net/can/vcan.c
index 603f53b81d86..32efb4b5f22c 100644
--- a/drivers/net/can/vcan.c
+++ b/drivers/net/can/vcan.c
@@ -158,6 +158,7 @@ static void vcan_setup(struct net_device *dev)
dev->addr_len = 0;
dev->tx_queue_len = 0;
dev->flags = IFF_NOARP;
+ dev->ml_priv = netdev_priv(dev);
/* set flags according to driver capabilities */
if (echo)
diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
index 3cc957f0a529..a496753ea53b 100644
--- a/drivers/net/can/vxcan.c
+++ b/drivers/net/can/vxcan.c
@@ -158,6 +158,7 @@ static void vxcan_setup(struct net_device *dev)
dev->flags = (IFF_NOARP|IFF_ECHO);
dev->netdev_ops = &vxcan_netdev_ops;
dev->needs_free_netdev = true;
+ dev->ml_priv = netdev_priv(dev) + ALIGN(sizeof(struct vxcan_priv), NETDEV_ALIGN);
}
/* forward declaration for rtnl_create_link() */
diff --git a/net/can/af_can.c b/net/can/af_can.c
index 9d79ce9bcd88..837f292da6c8 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -325,10 +325,12 @@ EXPORT_SYMBOL(can_send);
static struct can_dev_rcv_lists *can_dev_rcv_lists_find(struct net *net,
struct net_device *dev)
{
- if (!dev)
+ if (dev) {
+ struct can_ml_priv *ml_priv = dev->ml_priv;
+ return &ml_priv->dev_rcv_lists;
+ } else {
return net->can.rx_alldev_list;
- else
- return (struct can_dev_rcv_lists *)dev->ml_priv;
+ }
}
/**
@@ -590,12 +592,6 @@ void can_rx_unregister(struct net *net, struct net_device *dev, canid_t can_id,
if (rcv_lists_stats->rcv_entries > 0)
rcv_lists_stats->rcv_entries--;
- /* remove device structure requested by NETDEV_UNREGISTER */
- if (dev_rcv_lists->remove_on_zero_entries && !dev_rcv_lists->entries) {
- kfree(dev_rcv_lists);
- dev->ml_priv = NULL;
- }
-
out:
spin_unlock(&net->can.rcvlists_lock);
@@ -820,7 +816,6 @@ static int can_notifier(struct notifier_block *nb, unsigned long msg,
void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
- struct can_dev_rcv_lists *dev_rcv_lists;
if (dev->type != ARPHRD_CAN)
return NOTIFY_DONE;
@@ -828,33 +823,8 @@ static int can_notifier(struct notifier_block *nb, unsigned long msg,
switch (msg) {
case NETDEV_REGISTER:
-
- /* create new dev_rcv_lists for this device */
- dev_rcv_lists = kzalloc(sizeof(*dev_rcv_lists), GFP_KERNEL);
- if (!dev_rcv_lists)
- return NOTIFY_DONE;
- BUG_ON(dev->ml_priv);
- dev->ml_priv = dev_rcv_lists;
-
- break;
-
- case NETDEV_UNREGISTER:
- spin_lock(&dev_net(dev)->can.rcvlists_lock);
-
- dev_rcv_lists = dev->ml_priv;
- if (dev_rcv_lists) {
- if (dev_rcv_lists->entries)
- dev_rcv_lists->remove_on_zero_entries = 1;
- else {
- kfree(dev_rcv_lists);
- dev->ml_priv = NULL;
- }
- } else
- pr_err("can: notifier: receive list not found for dev "
- "%s\n", dev->name);
-
- spin_unlock(&dev_net(dev)->can.rcvlists_lock);
-
+ WARN(!dev->ml_priv,
+ "No CAN mid layer private allocated, please fix your driver and use alloc_candev()!\n");
break;
}
diff --git a/net/can/af_can.h b/net/can/af_can.h
index b79d7e4fd992..4e9d34a87fe9 100644
--- a/net/can/af_can.h
+++ b/net/can/af_can.h
@@ -71,7 +71,6 @@ struct can_dev_rcv_lists {
struct hlist_head rx[RX_MAX];
struct hlist_head rx_sff[CAN_SFF_RCV_ARRAY_SZ];
struct hlist_head rx_eff[CAN_EFF_RCV_ARRAY_SZ];
- int remove_on_zero_entries;
int entries;
};
--
2.19.0
