[NET]: Make the device list and device lookups per namespace.

This patch makes most of the generic device layer network
namespace safe.  This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables.  The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces.  The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace.  This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change.  Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 35 insertions, 31 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index dc3c15b726bc..7353b3e1f4fc 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -741,44 +741,48 @@ struct packet_type {
 #include <linux/notifier.h>
 
 extern struct net_device                loopback_dev;           /* The loopback */
-extern struct list_head                 dev_base_head;          /* All devices */
 extern rwlock_t                         dev_base_lock;          /* Device list lock */
 
-#define for_each_netdev(d)              \
-                list_for_each_entry(d, &dev_base_head, dev_list)
-#define for_each_netdev_safe(d, n)      \
-                list_for_each_entry_safe(d, n, &dev_base_head, dev_list)
-#define for_each_netdev_continue(d)             \
-                list_for_each_entry_continue(d, &dev_base_head, dev_list)
-#define net_device_entry(lh)    list_entry(lh, struct net_device, dev_list)
-
-static inline struct net_device *next_net_device(struct net_device *dev)
-{
-        struct list_head *lh;
 
-        lh = dev->dev_list.next;
-        return lh == &dev_base_head ? NULL : net_device_entry(lh);
-}
+#define for_each_netdev(net, d)         \
+                list_for_each_entry(d, &(net)->dev_base_head, dev_list)
+#define for_each_netdev_safe(net, d, n) \
+                list_for_each_entry_safe(d, n, &(net)->dev_base_head, dev_list)
+#define for_each_netdev_continue(net, d)                \
+                list_for_each_entry_continue(d, &(net)->dev_base_head, dev_list)
+#define net_device_entry(lh)    list_entry(lh, struct net_device, dev_list)
 
-static inline struct net_device *first_net_device(void)
-{
-        return list_empty(&dev_base_head) ? NULL :
-                net_device_entry(dev_base_head.next);
-}
+#define next_net_device(d)                                              \
+({                                                                      \
+        struct net_device *dev = d;                                     \
+        struct list_head *lh;                                           \
+        struct net *net;                                                \
+                                                                        \
+        net = dev->nd_net;                                              \
+        lh = dev->dev_list.next;                                        \
+        lh == &net->dev_base_head ? NULL : net_device_entry(lh);        \
+})
+
+#define first_net_device(N)                                     \
+({                                                              \
+        struct net *NET = (N);                                  \
+        list_empty(&NET->dev_base_head) ? NULL :                \
+                net_device_entry(NET->dev_base_head.next);      \
+})
 
 extern int                      netdev_boot_setup_check(struct net_device *dev);
 extern unsigned long            netdev_boot_base(const char *prefix, int unit);
-extern struct net_device    *dev_getbyhwaddr(unsigned short type, char *hwaddr);
-extern struct net_device *dev_getfirstbyhwtype(unsigned short type);
-extern struct net_device *__dev_getfirstbyhwtype(unsigned short type);
+extern struct net_device    *dev_getbyhwaddr(struct net *net, unsigned short type, char *hwaddr);
+extern struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type);
+extern struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type);
 extern void             dev_add_pack(struct packet_type *pt);
 extern void             dev_remove_pack(struct packet_type *pt);
 extern void             __dev_remove_pack(struct packet_type *pt);
 
-extern struct net_device        *dev_get_by_flags(unsigned short flags,
+extern struct net_device        *dev_get_by_flags(struct net *net, unsigned short flags,
                                                   unsigned short mask);
-extern struct net_device        *dev_get_by_name(const char *name);
-extern struct net_device        *__dev_get_by_name(const char *name);
+extern struct net_device        *dev_get_by_name(struct net *net, const char *name);
+extern struct net_device        *__dev_get_by_name(struct net *net, const char *name);
 extern int              dev_alloc_name(struct net_device *dev, const char *name);
 extern int              dev_open(struct net_device *dev);
 extern int              dev_close(struct net_device *dev);
@@ -790,8 +794,8 @@ extern void		synchronize_net(void);
 extern int              register_netdevice_notifier(struct notifier_block *nb);
 extern int              unregister_netdevice_notifier(struct notifier_block *nb);
 extern int              call_netdevice_notifiers(unsigned long val, void *v);
-extern struct net_device        *dev_get_by_index(int ifindex);
-extern struct net_device        *__dev_get_by_index(int ifindex);
+extern struct net_device        *dev_get_by_index(struct net *net, int ifindex);
+extern struct net_device        *__dev_get_by_index(struct net *net, int ifindex);
 extern int              dev_restart(struct net_device *dev);
 #ifdef CONFIG_NETPOLL_TRAP
 extern int              netpoll_trap(void);
@@ -1007,8 +1011,8 @@ extern int		netif_rx_ni(struct sk_buff *skb);
 #define HAVE_NETIF_RECEIVE_SKB 1
 extern int              netif_receive_skb(struct sk_buff *skb);
 extern int              dev_valid_name(const char *name);
-extern int              dev_ioctl(unsigned int cmd, void __user *);
-extern int              dev_ethtool(struct ifreq *);
+extern int              dev_ioctl(struct net *net, unsigned int cmd, void __user *);
+extern int              dev_ethtool(struct net *net, struct ifreq *);
 extern unsigned         dev_get_flags(const struct net_device *);
 extern int              dev_change_flags(struct net_device *, unsigned);
 extern int              dev_change_name(struct net_device *, char *);
@@ -1327,7 +1331,7 @@ extern void		dev_set_allmulti(struct net_device *dev, int inc);
 extern void             netdev_state_change(struct net_device *dev);
 extern void             netdev_features_change(struct net_device *dev);
 /* Load a device via the kmod */
-extern void             dev_load(const char *name);
+extern void             dev_load(struct net *net, const char *name);
 extern void             dev_mcast_init(void);
 extern int              netdev_max_backlog;
 extern int              weight_p;