net: bridge: add support for raw sysfs port options

This patch adds a new alternative store callback for port sysfs options
which takes a raw value (buf) and can use it directly. It is needed for the
backup port sysfs support since we have to pass the device by its name.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index ab4c7f8..4ac9400 100644 (file)
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -25,6 +25,15 @@ struct brport_attribute {
        struct attribute        attr;
        ssize_t (*show)(struct net_bridge_port *, char *);
        int (*store)(struct net_bridge_port *, unsigned long);
+       int (*store_raw)(struct net_bridge_port *, char *);
+};
+
+#define BRPORT_ATTR_RAW(_name, _mode, _show, _store)                   \
+const struct brport_attribute brport_attr_##_name = {                  \
+       .attr           = {.name = __stringify(_name),                  \
+                          .mode = _mode },                             \
+       .show           = _show,                                        \
+       .store_raw      = _store,                                       \
 };
 
 #define BRPORT_ATTR(_name, _mode, _show, _store)               \
@@ -269,27 +278,46 @@ static ssize_t brport_store(struct kobject *kobj,
        struct brport_attribute *brport_attr = to_brport_attr(attr);
        struct net_bridge_port *p = kobj_to_brport(kobj);
        ssize_t ret = -EINVAL;
-       char *endp;
        unsigned long val;
+       char *endp;
 
        if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
                return -EPERM;
 
-       val = simple_strtoul(buf, &endp, 0);
-       if (endp != buf) {
-               if (!rtnl_trylock())
-                       return restart_syscall();
-               if (p->dev && p->br && brport_attr->store) {
-                       spin_lock_bh(&p->br->lock);
-                       ret = brport_attr->store(p, val);
-                       spin_unlock_bh(&p->br->lock);
-                       if (!ret) {
-                               br_ifinfo_notify(RTM_NEWLINK, NULL, p);
-                               ret = count;
-                       }
+       if (!rtnl_trylock())
+               return restart_syscall();
+
+       if (!p->dev || !p->br)
+               goto out_unlock;
+
+       if (brport_attr->store_raw) {
+               char *buf_copy;
+
+               buf_copy = kstrndup(buf, count, GFP_KERNEL);
+               if (!buf_copy) {
+                       ret = -ENOMEM;
+                       goto out_unlock;
                }
-               rtnl_unlock();
+               spin_lock_bh(&p->br->lock);
+               ret = brport_attr->store_raw(p, buf_copy);
+               spin_unlock_bh(&p->br->lock);
+               kfree(buf_copy);
+       } else if (brport_attr->store) {
+               val = simple_strtoul(buf, &endp, 0);
+               if (endp == buf)
+                       goto out_unlock;
+               spin_lock_bh(&p->br->lock);
+               ret = brport_attr->store(p, val);
+               spin_unlock_bh(&p->br->lock);
        }
+
+       if (!ret) {
+               br_ifinfo_notify(RTM_NEWLINK, NULL, p);
+               ret = count;
+       }
+out_unlock:
+       rtnl_unlock();
+
        return ret;
 }