mac80211: dont use interface indices in drivers

This patch gets rid of the if_id stuff where possible in favour of
a new per-virtual-interface structure "struct ieee80211_vif". This
structure is located at the end of the per-interface structure and
contains a variable length driver-use data area.

This has two advantages:
 * removes the need to look up interfaces by if_id, this is better
   for working with network namespaces and performance
 * allows drivers to store and retrieve per-interface data without
   having to allocate own lists/hash tables

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 45 insertions, 25 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index be2a383b4776..24a8ad3f5073 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -280,6 +280,7 @@ struct ieee80211_low_level_stats {
  * the hardware to use given values (depending on what is supported). */
 
 struct ieee80211_tx_control {
+        struct ieee80211_vif *vif;
         int tx_rate; /* Transmit rate, given as the hw specific value for the
                       * rate (from struct ieee80211_rate) */
         int rts_cts_rate; /* Transmit rate for RTS/CTS frame, given as the hw
@@ -332,7 +333,6 @@ struct ieee80211_tx_control {
                              * packet dropping when probing higher rates, if hw
                              * supports multiple retry rates. -1 = not used */
         int type;       /* internal */
-        int ifindex;    /* internal */
 };
 
 
@@ -530,13 +530,25 @@ enum ieee80211_if_types {
 };
 
 /**
+ * struct ieee80211_vif - per-interface data
+ *
+ * Data in this structure is continually present for driver
+ * use during the life of a virtual interface.
+ *
+ * @drv_priv: data area for driver use, will always be aligned to
+ *      sizeof(void *).
+ */
+struct ieee80211_vif {
+        /* must be last */
+        u8 drv_priv[0] __attribute__((__aligned__(sizeof(void *))));
+};
+
+/**
  * struct ieee80211_if_init_conf - initial configuration of an interface
  *
- * @if_id: internal interface ID. This number has no particular meaning to
- *      drivers and the only allowed usage is to pass it to
- *      ieee80211_beacon_get() and ieee80211_get_buffered_bc() functions.
- *      This field is not valid for monitor interfaces
- *      (interfaces of %IEEE80211_IF_TYPE_MNTR type).
+ * @vif: pointer to a driver-use per-interface structure. The pointer
+ *      itself is also used for various functions including
+ *      ieee80211_beacon_get() and ieee80211_get_buffered_bc().
  * @type: one of &enum ieee80211_if_types constants. Determines the type of
  *      added/removed interface.
  * @mac_addr: pointer to MAC address of the interface. This pointer is valid
@@ -553,8 +565,8 @@ enum ieee80211_if_types {
  * in pure monitor mode.
  */
 struct ieee80211_if_init_conf {
-        int if_id;
         enum ieee80211_if_types type;
+        struct ieee80211_vif *vif;
         void *mac_addr;
 };
 
@@ -757,6 +769,9 @@ enum ieee80211_hw_flags {
  * @rate_control_algorithm: rate control algorithm for this hardware.
  *      If unset (NULL), the default algorithm will be used. Must be
  *      set before calling ieee80211_register_hw().
+ *
+ * @vif_data_size: size (in bytes) of the drv_priv data area
+ *      within &struct ieee80211_vif.
  */
 struct ieee80211_hw {
         struct ieee80211_conf conf;
@@ -767,6 +782,7 @@ struct ieee80211_hw {
         u32 flags;
         unsigned int extra_tx_headroom;
         int channel_change_time;
+        int vif_data_size;
         u8 queues;
         s8 max_rssi;
         s8 max_signal;
@@ -1076,7 +1092,8 @@ struct ieee80211_ops {
                                  struct ieee80211_if_init_conf *conf);
         int (*config)(struct ieee80211_hw *hw, struct ieee80211_conf *conf);
         int (*config_interface)(struct ieee80211_hw *hw,
-                                int if_id, struct ieee80211_if_conf *conf);
+                                struct ieee80211_vif *vif,
+                                struct ieee80211_if_conf *conf);
         void (*configure_filter)(struct ieee80211_hw *hw,
                                  unsigned int changed_flags,
                                  unsigned int *total_flags,
@@ -1094,7 +1111,7 @@ struct ieee80211_ops {
         int (*set_frag_threshold)(struct ieee80211_hw *hw, u32 value);
         int (*set_retry_limit)(struct ieee80211_hw *hw,
                                u32 short_retry, u32 long_retr);
-        void (*sta_notify)(struct ieee80211_hw *hw, int if_id,
+        void (*sta_notify)(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                         enum sta_notify_cmd, const u8 *addr);
         void (*erp_ie_changed)(struct ieee80211_hw *hw, u8 changes,
                                int cts_protection, int preamble);
@@ -1309,7 +1326,7 @@ void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
 /**
  * ieee80211_beacon_get - beacon generation function
  * @hw: pointer obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @control: will be filled with information needed to send this beacon.
  *
  * If the beacon frames are generated by the host system (i.e., not in
@@ -1320,13 +1337,13 @@ void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  * is responsible of freeing it.
  */
 struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
-                                     int if_id,
+                                     struct ieee80211_vif *vif,
                                      struct ieee80211_tx_control *control);
 
 /**
  * ieee80211_rts_get - RTS frame generation function
  * @hw: pointer obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @frame: pointer to the frame that is going to be protected by the RTS.
  * @frame_len: the frame length (in octets).
  * @frame_txctl: &struct ieee80211_tx_control of the frame.
@@ -1337,7 +1354,7 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
  * the next RTS frame from the 802.11 code. The low-level is responsible
  * for calling this function before and RTS frame is needed.
  */
-void ieee80211_rts_get(struct ieee80211_hw *hw, int if_id,
+void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                        const void *frame, size_t frame_len,
                        const struct ieee80211_tx_control *frame_txctl,
                        struct ieee80211_rts *rts);
@@ -1345,7 +1362,7 @@ void ieee80211_rts_get(struct ieee80211_hw *hw, int if_id,
 /**
  * ieee80211_rts_duration - Get the duration field for an RTS frame
  * @hw: pointer obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @frame_len: the length of the frame that is going to be protected by the RTS.
  * @frame_txctl: &struct ieee80211_tx_control of the frame.
  *
@@ -1353,14 +1370,14 @@ void ieee80211_rts_get(struct ieee80211_hw *hw, int if_id,
  * the duration field, the low-level driver uses this function to receive
  * the duration field value in little-endian byteorder.
  */
-__le16 ieee80211_rts_duration(struct ieee80211_hw *hw, int if_id,
-                              size_t frame_len,
+__le16 ieee80211_rts_duration(struct ieee80211_hw *hw,
+                              struct ieee80211_vif *vif, size_t frame_len,
                               const struct ieee80211_tx_control *frame_txctl);
 
 /**
  * ieee80211_ctstoself_get - CTS-to-self frame generation function
  * @hw: pointer obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @frame: pointer to the frame that is going to be protected by the CTS-to-self.
  * @frame_len: the frame length (in octets).
  * @frame_txctl: &struct ieee80211_tx_control of the frame.
@@ -1371,7 +1388,8 @@ __le16 ieee80211_rts_duration(struct ieee80211_hw *hw, int if_id,
  * the next CTS-to-self frame from the 802.11 code. The low-level is responsible
  * for calling this function before and CTS-to-self frame is needed.
  */
-void ieee80211_ctstoself_get(struct ieee80211_hw *hw, int if_id,
+void ieee80211_ctstoself_get(struct ieee80211_hw *hw,
+                             struct ieee80211_vif *vif,
                              const void *frame, size_t frame_len,
                              const struct ieee80211_tx_control *frame_txctl,
                              struct ieee80211_cts *cts);
@@ -1379,7 +1397,7 @@ void ieee80211_ctstoself_get(struct ieee80211_hw *hw, int if_id,
 /**
  * ieee80211_ctstoself_duration - Get the duration field for a CTS-to-self frame
  * @hw: pointer obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @frame_len: the length of the frame that is going to be protected by the CTS-to-self.
  * @frame_txctl: &struct ieee80211_tx_control of the frame.
  *
@@ -1387,28 +1405,30 @@ void ieee80211_ctstoself_get(struct ieee80211_hw *hw, int if_id,
  * the duration field, the low-level driver uses this function to receive
  * the duration field value in little-endian byteorder.
  */
-__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw, int if_id,
+__le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
+                                    struct ieee80211_vif *vif,
                                     size_t frame_len,
                                     const struct ieee80211_tx_control *frame_txctl);
 
 /**
  * ieee80211_generic_frame_duration - Calculate the duration field for a frame
  * @hw: pointer obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @frame_len: the length of the frame.
  * @rate: the rate (in 100kbps) at which the frame is going to be transmitted.
  *
  * Calculate the duration field of some generic frame, given its
  * length and transmission rate (in 100kbps).
  */
-__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, int if_id,
+__le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw,
+                                        struct ieee80211_vif *vif,
                                         size_t frame_len,
                                         int rate);
 
 /**
  * ieee80211_get_buffered_bc - accessing buffered broadcast and multicast frames
  * @hw: pointer as obtained from ieee80211_alloc_hw().
- * @if_id: interface ID from &struct ieee80211_if_init_conf.
+ * @vif: &struct ieee80211_vif pointer from &struct ieee80211_if_init_conf.
  * @control: will be filled with information needed to send returned frame.
  *
  * Function for accessing buffered broadcast and multicast frames. If
@@ -1427,7 +1447,7 @@ __le16 ieee80211_generic_frame_duration(struct ieee80211_hw *hw, int if_id,
  * use common code for all beacons.
  */
 struct sk_buff *
-ieee80211_get_buffered_bc(struct ieee80211_hw *hw, int if_id,
+ieee80211_get_buffered_bc(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                           struct ieee80211_tx_control *control);
 
 /**
@@ -1517,7 +1537,7 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw);
  */
 void ieee80211_iterate_active_interfaces(struct ieee80211_hw *hw,
                                          void (*iterator)(void *data, u8 *mac,
-                                                          int if_id),
+                                                struct ieee80211_vif *vif),
                                          void *data);
 
 #endif /* MAC80211_H */