bonding: simplify bond_3ad_update_lacp_rate and use RTNL for sync
We can drop the use of bond->lock for mutual exclusion in
bond_3ad_update_lacp_rate and use RTNL in the sysfs store function
instead. This way we'll prevent races with mode change and interface
up/down as well as simplify update_lacp_rate by removing the check for
port->slave because it'll always be initialized (done while enslaving
with RTNL). This change will also help in the future removal of reader
bond->lock from bond_enslave.
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index 0f539de..ce46776 100644
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -852,8 +852,11 @@
struct device_attribute *attr,
const char *buf, size_t count)
{
- int new_value, ret = count;
struct bonding *bond = to_bond(d);
+ int new_value, ret = count;
+
+ if (!rtnl_trylock())
+ return restart_syscall();
if (bond->dev->flags & IFF_UP) {
pr_err("%s: Unable to update LACP rate because interface is up.\n",
@@ -883,6 +886,8 @@
ret = -EINVAL;
}
out:
+ rtnl_unlock();
+
return ret;
}
static DEVICE_ATTR(lacp_rate, S_IRUGO | S_IWUSR,