[Bridge] [PATCH net-next 1/2] net: bridge: add support for raw sysfs port options

[Nikolay Aleksandrov]

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 <niko...@cumulusnetworks.com>
---
There are a few checkpatch warnings here because of the old code, I've
noted them in my todo and will send separate patch for simple_strtoul
and the function prototypes.

 net/bridge/br_sysfs_if.c | 49 +++++++++++++++++++++++++++++++++---------------
 1 file changed, 34 insertions(+), 15 deletions(-)

diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index f99c5bf5c906..38c58879423d 100644
--- 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)               \
@@ -270,27 +279,37 @@ static ssize_t brport_store(struct kobject *kobj,
        struct brport_attribute *brport_attr = to_brport_attr(attr);
        struct net_bridge_port *p = 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;
-                       }
-               }
-               rtnl_unlock();
+       if (!rtnl_trylock())
+               return restart_syscall();
+
+       if (!p->dev || !p->br)
+               goto out_unlock;
+
+       if (brport_attr->store_raw) {
+               spin_lock_bh(&p->br->lock);
+               ret = brport_attr->store_raw(p, (char *)buf);
+               spin_unlock_bh(&p->br->lock);
+       } 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;
 }
 
-- 
2.11.0