From: Andrey Shvetsov <andrey.shvetsov@xxxxxx>
This adds the dev_hold and dev_put calls to the functions
aim_resume_tx_channel, aim_rx_data and on_netinfo to postpone the
unregistration of the used net device.
Signed-off-by: Andrey Shvetsov <andrey.shvetsov@xxxxxx>
Signed-off-by: Christian Gromm <christian.gromm@xxxxxxxxxxxxx>
---
drivers/staging/most/aim-network/networking.c | 78 +++++++++++++++++++--------
1 file changed, 55 insertions(+), 23 deletions(-)
diff --git a/drivers/staging/most/aim-network/networking.c b/drivers/staging/most/aim-network/networking.c
index 217265cb..4c259c2 100644
--- a/drivers/staging/most/aim-network/networking.c
+++ b/drivers/staging/most/aim-network/networking.c
@@ -73,7 +73,7 @@ struct net_dev_context {
static struct list_head net_devices = LIST_HEAD_INIT(net_devices);
static struct mutex probe_disc_mt; /* ch->linked = true, most_nd_open */
-static struct spinlock list_lock;
+static struct spinlock list_lock; /* list_head, ch->linked = false, dev_hold */
static struct most_aim aim;
static int skb_to_mamac(const struct sk_buff *skb, struct mbo *mbo)
@@ -271,21 +271,29 @@ static void most_nd_setup(struct net_device *dev)
dev->netdev_ops = &most_nd_ops;
}
-static struct net_dev_context *get_net_dev_context(
- struct most_interface *iface)
+static struct net_dev_context *get_net_dev(struct most_interface *iface)
+{
+ struct net_dev_context *nd;
+
+ list_for_each_entry(nd, &net_devices, list)
+ if (nd->iface == iface)
+ return nd;
+ return NULL;
+}
+
+static struct net_dev_context *get_net_dev_hold(struct most_interface *iface)
{
struct net_dev_context *nd;
unsigned long flags;
spin_lock_irqsave(&list_lock, flags);
- list_for_each_entry(nd, &net_devices, list) {
- if (nd->iface == iface) {
- spin_unlock_irqrestore(&list_lock, flags);
- return nd;
- }
- }
+ nd = get_net_dev(iface);
+ if (nd && nd->rx.linked && nd->tx.linked)
+ dev_hold(nd->dev);
+ else
+ nd = NULL;
spin_unlock_irqrestore(&list_lock, flags);
- return NULL;
+ return nd;
}
static int aim_probe_channel(struct most_interface *iface, int channel_idx,
@@ -305,7 +313,7 @@ static int aim_probe_channel(struct most_interface *iface, int channel_idx,
return -EINVAL;
mutex_lock(&probe_disc_mt);
- nd = get_net_dev_context(iface);
+ nd = get_net_dev(iface);
if (!nd) {
dev = alloc_netdev(sizeof(struct net_dev_context), "meth%d",
NET_NAME_UNKNOWN, most_nd_setup);
@@ -354,7 +362,7 @@ static int aim_disconnect_channel(struct most_interface *iface,
int ret = 0;
mutex_lock(&probe_disc_mt);
- nd = get_net_dev_context(iface);
+ nd = get_net_dev(iface);
if (!nd) {
ret = -EINVAL;
goto unlock;
@@ -370,12 +378,15 @@ static int aim_disconnect_channel(struct most_interface *iface,
}
if (nd->rx.linked && nd->tx.linked) {
+ spin_lock_irqsave(&list_lock, flags);
+ ch->linked = false;
+ spin_unlock_irqrestore(&list_lock, flags);
+
/*
* do not call most_stop_channel() here, because channels are
* going to be closed in ndo_stop() after unregister_netdev()
*/
unregister_netdev(nd->dev);
- ch->linked = false;
} else {
spin_lock_irqsave(&list_lock, flags);
list_del(&nd->list);
@@ -394,11 +405,17 @@ static int aim_resume_tx_channel(struct most_interface *iface,
{
struct net_dev_context *nd;
- nd = get_net_dev_context(iface);
- if (!nd || nd->tx.ch_id != channel_idx)
+ nd = get_net_dev_hold(iface);
+ if (!nd)
return 0;
+ if (nd->tx.ch_id != channel_idx)
+ goto put_nd;
+
netif_wake_queue(nd->dev);
+
+put_nd:
+ dev_put(nd->dev);
return 0;
}
@@ -411,21 +428,31 @@ static int aim_rx_data(struct mbo *mbo)
struct sk_buff *skb;
struct net_device *dev;
unsigned int skb_len;
+ int ret = 0;
- nd = get_net_dev_context(mbo->ifp);
- if (!nd || nd->rx.ch_id != mbo->hdm_channel_id)
+ nd = get_net_dev_hold(mbo->ifp);
+ if (!nd)
return -EIO;
+ if (nd->rx.ch_id != mbo->hdm_channel_id) {
+ ret = -EIO;
+ goto put_nd;
+ }
+
dev = nd->dev;
if (nd->is_mamac) {
- if (!PMS_IS_MAMAC(buf, len))
- return -EIO;
+ if (!PMS_IS_MAMAC(buf, len)) {
+ ret = -EIO;
+ goto put_nd;
+ }
skb = dev_alloc_skb(len - MDP_HDR_LEN + 2 * ETH_ALEN + 2);
} else {
- if (!PMS_IS_MEP(buf, len))
- return -EIO;
+ if (!PMS_IS_MEP(buf, len)) {
+ ret = -EIO;
+ goto put_nd;
+ }
skb = dev_alloc_skb(len - MEP_HDR_LEN);
}
@@ -468,7 +495,10 @@ static int aim_rx_data(struct mbo *mbo)
out:
most_put_mbo(mbo);
- return 0;
+
+put_nd:
+ dev_put(nd->dev);
+ return ret;
}
static struct most_aim aim = {
@@ -504,7 +534,7 @@ static void on_netinfo(struct most_interface *iface,
struct net_device *dev;
const u8 *m = mac_addr;
- nd = get_net_dev_context(iface);
+ nd = get_net_dev_hold(iface);
if (!nd)
return;
@@ -526,6 +556,8 @@ static void on_netinfo(struct most_interface *iface,
m[0], m[1], m[2], m[3], m[4], m[5]);
}
}
+
+ dev_put(nd->dev);
}
module_init(most_net_init);
--
2.7.4
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