netdev: network device operations infrastructure

This patch changes the network device internal API to move adminstrative
operations out of the network device structure and into a separate structure.

This patch involves some hackery to maintain compatablity between the
new and old model, so all 300+ drivers don't have to be changed at once.
For drivers that aren't converted yet, the netdevice_ops virt function list
still resides in the net_device structure. For old protocols, the new
net_device_ops are copied out to the old net_device pointers.

After the transistion is completed the nag message can be changed to
an WARN_ON, and the compatiablity code can be made configurable.

Some function pointers aren't moved:
* destructor can't be in net_device_ops because
  it may need to be referenced after the module is unloaded.
* neighbor setup is manipulated in a couple of places that need special
  consideration
* hard_start_xmit is in the fast path for transmit.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 168 insertions, 64 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 12d7f4469dc9..9060f5f3517a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -451,6 +451,131 @@ struct netdev_queue {
         struct Qdisc            *qdisc_sleeping;
 } ____cacheline_aligned_in_smp;
 
+
+/*
+ * This structure defines the management hooks for network devices.
+ * The following hooks can bed defined and are optonal (can be null)
+ * unless otherwise noted.
+ *
+ * int (*ndo_init)(struct net_device *dev);
+ *     This function is called once when network device is registered.
+ *     The network device can use this to any late stage initializaton
+ *     or semantic validattion. It can fail with an error code which will
+ *     be propogated back to register_netdev
+ *
+ * void (*ndo_uninit)(struct net_device *dev);
+ *     This function is called when device is unregistered or when registration
+ *     fails. It is not called if init fails.
+ *
+ * int (*ndo_open)(struct net_device *dev);
+ *     This function is called when network device transistions to the up
+ *     state.
+ *
+ * int (*ndo_stop)(struct net_device *dev);
+ *     This function is called when network device transistions to the down
+ *     state.
+ *
+ * void (*ndo_change_rx_flags)(struct net_device *dev, int flags);
+ *      This function is called to allow device receiver to make
+ *      changes to configuration when multicast or promiscious is enabled.
+ *
+ * void (*ndo_set_rx_mode)(struct net_device *dev);
+ *      This function is called device changes address list filtering.
+ *
+ * void (*ndo_set_multicast_list)(struct net_device *dev);
+ *      This function is called when the multicast address list changes.
+ *
+ * int (*ndo_set_mac_address)(struct net_device *dev, void *addr);
+ *      This function  is called when the Media Access Control address
+ *      needs to be changed. If not this interface is not defined, the
+ *      mac address can not be changed.
+ *
+ * int (*ndo_validate_addr)(struct net_device *dev);
+ *      Test if Media Access Control address is valid for the device.
+ *
+ * int (*ndo_do_ioctl)(struct net_device *dev, struct ifreq *ifr, int cmd);
+ *      Called when a user request an ioctl which can't be handled by
+ *      the generic interface code. If not defined ioctl's return
+ *      not supported error code.
+ *
+ * int (*ndo_set_config)(struct net_device *dev, struct ifmap *map);
+ *      Used to set network devices bus interface parameters. This interface
+ *      is retained for legacy reason, new devices should use the bus
+ *      interface (PCI) for low level management.
+ *
+ * int (*ndo_change_mtu)(struct net_device *dev, int new_mtu);
+ *      Called when a user wants to change the Maximum Transfer Unit
+ *      of a device. If not defined, any request to change MTU will
+ *      will return an error.
+ *
+ * void (*ndo_tx_timeout) (struct net_device *dev);
+ *      Callback uses when the transmitter has not made any progress
+ *      for dev->watchdog ticks.
+ *
+ * struct net_device_stats* (*get_stats)(struct net_device *dev);
+ *      Called when a user wants to get the network device usage
+ *      statistics. If not defined, the counters in dev->stats will
+ *      be used.
+ *
+ * void (*ndo_vlan_rx_register)(struct net_device *dev, struct vlan_group *grp);
+ *      If device support VLAN receive accleration
+ *      (ie. dev->features & NETIF_F_HW_VLAN_RX), then this function is called
+ *      when vlan groups for the device changes.  Note: grp is NULL
+ *      if no vlan's groups are being used.
+ *
+ * void (*ndo_vlan_rx_add_vid)(struct net_device *dev, unsigned short vid);
+ *      If device support VLAN filtering (dev->features & NETIF_F_HW_VLAN_FILTER)
+ *      this function is called when a VLAN id is registered.
+ *
+ * void (*ndo_vlan_rx_kill_vid)(struct net_device *dev, unsigned short vid);
+ *      If device support VLAN filtering (dev->features & NETIF_F_HW_VLAN_FILTER)
+ *      this function is called when a VLAN id is unregistered.
+ *
+ * void (*ndo_poll_controller)(struct net_device *dev);
+ */
+struct net_device_ops {
+        int                     (*ndo_init)(struct net_device *dev);
+        void                    (*ndo_uninit)(struct net_device *dev);
+        int                     (*ndo_open)(struct net_device *dev);
+        int                     (*ndo_stop)(struct net_device *dev);
+#define HAVE_CHANGE_RX_FLAGS
+        void                    (*ndo_change_rx_flags)(struct net_device *dev,
+                                                       int flags);
+#define HAVE_SET_RX_MODE
+        void                    (*ndo_set_rx_mode)(struct net_device *dev);
+#define HAVE_MULTICAST
+        void                    (*ndo_set_multicast_list)(struct net_device *dev);
+#define HAVE_SET_MAC_ADDR
+        int                     (*ndo_set_mac_address)(struct net_device *dev,
+                                                       void *addr);
+#define HAVE_VALIDATE_ADDR
+        int                     (*ndo_validate_addr)(struct net_device *dev);
+#define HAVE_PRIVATE_IOCTL
+        int                     (*ndo_do_ioctl)(struct net_device *dev,
+                                                struct ifreq *ifr, int cmd);
+#define HAVE_SET_CONFIG
+        int                     (*ndo_set_config)(struct net_device *dev,
+                                                  struct ifmap *map);
+#define HAVE_CHANGE_MTU
+        int                     (*ndo_change_mtu)(struct net_device *dev, int new_mtu);
+
+#define HAVE_TX_TIMEOUT
+        void                    (*ndo_tx_timeout) (struct net_device *dev);
+
+        struct net_device_stats* (*ndo_get_stats)(struct net_device *dev);
+
+        void                    (*ndo_vlan_rx_register)(struct net_device *dev,
+                                                        struct vlan_group *grp);
+        void                    (*ndo_vlan_rx_add_vid)(struct net_device *dev,
+                                                       unsigned short vid);
+        void                    (*ndo_vlan_rx_kill_vid)(struct net_device *dev,
+                                                        unsigned short vid);
+#ifdef CONFIG_NET_POLL_CONTROLLER
+#define HAVE_NETDEV_POLL
+        void                    (*ndo_poll_controller)(struct net_device *dev);
+#endif
+};
+
 /*
  *      The DEVICE structure.
  *      Actually, this whole structure is a big mistake.  It mixes I/O
@@ -498,11 +623,6 @@ struct net_device
 #ifdef CONFIG_NETPOLL
         struct list_head        napi_list;
 #endif
-        
-        /* The device initialization function. Called only once. */
-        int                     (*init)(struct net_device *dev);
-
-        /* ------- Fields preinitialized in Space.c finish here ------- */
 
         /* Net device features */
         unsigned long           features;
@@ -546,15 +666,13 @@ struct net_device
          * for all in netdev_increment_features.
          */
 #define NETIF_F_ONE_FOR_ALL     (NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ROBUST | \
-                                 NETIF_F_SG | NETIF_F_HIGHDMA | \
+                                 NETIF_F_SG | NETIF_F_HIGHDMA |         \
                                  NETIF_F_FRAGLIST)
 
         /* Interface index. Unique device identifier    */
         int                     ifindex;
         int                     iflink;
 
-
-        struct net_device_stats* (*get_stats)(struct net_device *dev);
         struct net_device_stats stats;
 
 #ifdef CONFIG_WIRELESS_EXT
@@ -564,18 +682,13 @@ struct net_device
         /* Instance data managed by the core of Wireless Extensions. */
         struct iw_public_data * wireless_data;
 #endif
+        /* Management operations */
+        const struct net_device_ops *netdev_ops;
         const struct ethtool_ops *ethtool_ops;
 
         /* Hardware header description */
         const struct header_ops *header_ops;
 
-        /*
-         * This marks the end of the "visible" part of the structure. All
-         * fields hereafter are internal to the system, and may change at
-         * will (read: may be cleaned up at will).
-         */
-
-
         unsigned int            flags;  /* interface flags (a la BSD)   */
         unsigned short          gflags;
         unsigned short          priv_flags; /* Like 'flags' but invisible to userspace. */
@@ -634,7 +747,7 @@ struct net_device
         unsigned long           last_rx;        /* Time of last Rx      */
         /* Interface address info used in eth_type_trans() */
         unsigned char           dev_addr[MAX_ADDR_LEN]; /* hw address, (before bcast 
-                                                        because most packets are unicast) */
+                                                           because most packets are unicast) */
 
         unsigned char           broadcast[MAX_ADDR_LEN];        /* hw bcast add */
 
@@ -648,6 +761,10 @@ struct net_device
         /* Number of TX queues currently active in device  */
         unsigned int            real_num_tx_queues;
 
+        /* Map buffer to appropriate transmit queue */
+        u16                     (*select_queue)(struct net_device *dev,
+                                                struct sk_buff *skb);
+
         unsigned long           tx_queue_len;   /* Max frames per queue allowed */
         spinlock_t              tx_global_lock;
 /*
@@ -662,9 +779,6 @@ struct net_device
         int                     watchdog_timeo; /* used by dev_watchdog() */
         struct timer_list       watchdog_timer;
 
-/*
- * refcnt is a very hot point, so align it on SMP
- */
         /* Number of references to this device */
         atomic_t                refcnt ____cacheline_aligned_in_smp;
 
@@ -683,56 +797,14 @@ struct net_device
                NETREG_RELEASED,         /* called free_netdev */
         } reg_state;
 
-        /* Called after device is detached from network. */
-        void                    (*uninit)(struct net_device *dev);
-        /* Called after last user reference disappears. */
-        void                    (*destructor)(struct net_device *dev);
+        /* Called from unregister, can be used to call free_netdev */
+        void (*destructor)(struct net_device *dev);
 
-        /* Pointers to interface service routines.      */
-        int                     (*open)(struct net_device *dev);
-        int                     (*stop)(struct net_device *dev);
-#define HAVE_NETDEV_POLL
-#define HAVE_CHANGE_RX_FLAGS
-        void                    (*change_rx_flags)(struct net_device *dev,
-                                                   int flags);
-#define HAVE_SET_RX_MODE
-        void                    (*set_rx_mode)(struct net_device *dev);
-#define HAVE_MULTICAST                   
-        void                    (*set_multicast_list)(struct net_device *dev);
-#define HAVE_SET_MAC_ADDR                
-        int                     (*set_mac_address)(struct net_device *dev,
-                                                   void *addr);
-#define HAVE_VALIDATE_ADDR
-        int                     (*validate_addr)(struct net_device *dev);
-#define HAVE_PRIVATE_IOCTL
-        int                     (*do_ioctl)(struct net_device *dev,
-                                            struct ifreq *ifr, int cmd);
-#define HAVE_SET_CONFIG
-        int                     (*set_config)(struct net_device *dev,
-                                              struct ifmap *map);
-#define HAVE_CHANGE_MTU
-        int                     (*change_mtu)(struct net_device *dev, int new_mtu);
+        int (*neigh_setup)(struct net_device *dev, struct neigh_parms *);
 
-#define HAVE_TX_TIMEOUT
-        void                    (*tx_timeout) (struct net_device *dev);
-
-        void                    (*vlan_rx_register)(struct net_device *dev,
-                                                    struct vlan_group *grp);
-        void                    (*vlan_rx_add_vid)(struct net_device *dev,
-                                                   unsigned short vid);
-        void                    (*vlan_rx_kill_vid)(struct net_device *dev,
-                                                    unsigned short vid);
-
-        int                     (*neigh_setup)(struct net_device *dev, struct neigh_parms *);
 #ifdef CONFIG_NETPOLL
         struct netpoll_info     *npinfo;
 #endif
-#ifdef CONFIG_NET_POLL_CONTROLLER
-        void                    (*poll_controller)(struct net_device *dev);
-#endif
-
-        u16                     (*select_queue)(struct net_device *dev,
-                                                struct sk_buff *skb);
 
 #ifdef CONFIG_NET_NS
         /* Network namespace this network device is inside */
@@ -763,6 +835,38 @@ struct net_device
         /* for setting kernel sock attribute on TCP connection setup */
 #define GSO_MAX_SIZE            65536
         unsigned int            gso_max_size;
+
+#ifdef CONFIG_COMPAT_NET_DEV_OPS
+        struct {
+                int                     (*init)(struct net_device *dev);
+                void                    (*uninit)(struct net_device *dev);
+                int                     (*open)(struct net_device *dev);
+                int                     (*stop)(struct net_device *dev);
+                void                    (*change_rx_flags)(struct net_device *dev,
+                                                           int flags);
+                void                    (*set_rx_mode)(struct net_device *dev);
+                void                    (*set_multicast_list)(struct net_device *dev);
+                int                     (*set_mac_address)(struct net_device *dev,
+                                                           void *addr);
+                int                     (*validate_addr)(struct net_device *dev);
+                int                     (*do_ioctl)(struct net_device *dev,
+                                                    struct ifreq *ifr, int cmd);
+                int                     (*set_config)(struct net_device *dev,
+                                                      struct ifmap *map);
+                int                     (*change_mtu)(struct net_device *dev, int new_mtu);
+                void                    (*tx_timeout) (struct net_device *dev);
+                struct net_device_stats* (*get_stats)(struct net_device *dev);
+                void                    (*vlan_rx_register)(struct net_device *dev,
+                                                            struct vlan_group *grp);
+                void                    (*vlan_rx_add_vid)(struct net_device *dev,
+                                                           unsigned short vid);
+                void                    (*vlan_rx_kill_vid)(struct net_device *dev,
+                                                            unsigned short vid);
+#ifdef CONFIG_NET_POLL_CONTROLLER
+                void                    (*poll_controller)(struct net_device *dev);
+#endif
+#endif
+        };
 };
 #define to_net_dev(d) container_of(d, struct net_device, dev)