[PATCH] net: swich device attribute creation to default attrs

Recent udev versions don't longer cover bad sysfs timing with built-in
logic. Explicit rules are required to do that. For net devices, the
following is needed:
  ACTION=="add", SUBSYSTEM=="net", WAIT_FOR_SYSFS="address"
to handle access to net device properties from an event handler without
races.

This patch changes the main net attributes to be created by the driver
core, which is done _before_ the event is sent out and will not require
the stat() loop of the WAIT_FOR_SYSFS key.

Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 21 insertions, 47 deletions

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 198655dd9a77..e1da81d261d1 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -84,16 +84,11 @@ static ssize_t netdev_store(struct class_device *dev,
         return ret;
 }
 
-/* generate a read-only network device class attribute */
-#define NETDEVICE_ATTR(field, format_string)                            \
-NETDEVICE_SHOW(field, format_string)                                    \
-static CLASS_DEVICE_ATTR(field, S_IRUGO, show_##field, NULL)            \
-
-NETDEVICE_ATTR(addr_len, fmt_dec);
-NETDEVICE_ATTR(iflink, fmt_dec);
-NETDEVICE_ATTR(ifindex, fmt_dec);
-NETDEVICE_ATTR(features, fmt_long_hex);
-NETDEVICE_ATTR(type, fmt_dec);
+NETDEVICE_SHOW(addr_len, fmt_dec);
+NETDEVICE_SHOW(iflink, fmt_dec);
+NETDEVICE_SHOW(ifindex, fmt_dec);
+NETDEVICE_SHOW(features, fmt_long_hex);
+NETDEVICE_SHOW(type, fmt_dec);
 
 /* use same locking rules as GIFHWADDR ioctl's */
 static ssize_t format_addr(char *buf, const unsigned char *addr, int len)
@@ -136,10 +131,6 @@ static ssize_t show_carrier(struct class_device *dev, char *buf)
         return -EINVAL;
 }
 
-static CLASS_DEVICE_ATTR(address, S_IRUGO, show_address, NULL);
-static CLASS_DEVICE_ATTR(broadcast, S_IRUGO, show_broadcast, NULL);
-static CLASS_DEVICE_ATTR(carrier, S_IRUGO, show_carrier, NULL);
-
 /* read-write attributes */
 NETDEVICE_SHOW(mtu, fmt_dec);
 
@@ -153,8 +144,6 @@ static ssize_t store_mtu(struct class_device *dev, const char *buf, size_t len)
         return netdev_store(dev, buf, len, change_mtu);
 }
 
-static CLASS_DEVICE_ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu);
-
 NETDEVICE_SHOW(flags, fmt_hex);
 
 static int change_flags(struct net_device *net, unsigned long new_flags)
@@ -167,8 +156,6 @@ static ssize_t store_flags(struct class_device *dev, const char *buf, size_t len
         return netdev_store(dev, buf, len, change_flags);
 }
 
-static CLASS_DEVICE_ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags);
-
 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
 
 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
@@ -182,9 +169,6 @@ static ssize_t store_tx_queue_len(struct class_device *dev, const char *buf, siz
         return netdev_store(dev, buf, len, change_tx_queue_len);
 }
 
-static CLASS_DEVICE_ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len, 
-                         store_tx_queue_len);
-
 NETDEVICE_SHOW(weight, fmt_dec);
 
 static int change_weight(struct net_device *net, unsigned long new_weight)
@@ -198,24 +182,21 @@ static ssize_t store_weight(struct class_device *dev, const char *buf, size_t le
         return netdev_store(dev, buf, len, change_weight);
 }
 
-static CLASS_DEVICE_ATTR(weight, S_IRUGO | S_IWUSR, show_weight, 
-                         store_weight);
-
-
-static struct class_device_attribute *net_class_attributes[] = {
-        &class_device_attr_ifindex,
-        &class_device_attr_iflink,
-        &class_device_attr_addr_len,
-        &class_device_attr_tx_queue_len,
-        &class_device_attr_features,
-        &class_device_attr_mtu,
-        &class_device_attr_flags,
-        &class_device_attr_weight,
-        &class_device_attr_type,
-        &class_device_attr_address,
-        &class_device_attr_broadcast,
-        &class_device_attr_carrier,
-        NULL
+static struct class_device_attribute net_class_attributes[] = {
+        __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
+        __ATTR(iflink, S_IRUGO, show_iflink, NULL),
+        __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
+        __ATTR(features, S_IRUGO, show_features, NULL),
+        __ATTR(type, S_IRUGO, show_type, NULL),
+        __ATTR(address, S_IRUGO, show_address, NULL),
+        __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
+        __ATTR(carrier, S_IRUGO, show_carrier, NULL),
+        __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
+        __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
+        __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
+               store_tx_queue_len),
+        __ATTR(weight, S_IRUGO | S_IWUSR, show_weight, store_weight),
+        {}
 };
 
 /* Show a given an attribute in the statistics group */
@@ -407,6 +388,7 @@ static void netdev_release(struct class_device *cd)
 static struct class net_class = {
         .name = "net",
         .release = netdev_release,
+        .class_dev_attrs = net_class_attributes,
 #ifdef CONFIG_HOTPLUG
         .uevent = netdev_uevent,
 #endif
@@ -431,8 +413,6 @@ void netdev_unregister_sysfs(struct net_device * net)
 int netdev_register_sysfs(struct net_device *net)
 {
         struct class_device *class_dev = &(net->class_dev);
-        int i;
-        struct class_device_attribute *attr;
         int ret;
 
         class_dev->class = &net_class;
@@ -442,12 +422,6 @@ int netdev_register_sysfs(struct net_device *net)
         if ((ret = class_device_register(class_dev)))
                 goto out;
 
-        for (i = 0; (attr = net_class_attributes[i]) != NULL; i++) {
-                if ((ret = class_device_create_file(class_dev, attr)))
-                    goto out_unreg;
-        }
-
-
         if (net->get_stats &&
             (ret = sysfs_create_group(&class_dev->kobj, &netstat_group)))
                 goto out_unreg;