2 files changed, 209 insertions, 1 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 281a2bb6a6ec..0ea497cb607c 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -77,6 +77,39 @@
  */
 
 /**
+ * DOC: Virtual interface / concurrency capabilities
+ *
+ * Some devices are able to operate with virtual MACs, they can have
+ * more than one virtual interface. The capability handling for this
+ * is a bit complex though, as there may be a number of restrictions
+ * on the types of concurrency that are supported.
+ *
+ * To start with, each device supports the interface types listed in
+ * the %NL80211_ATTR_SUPPORTED_IFTYPES attribute, but by listing the
+ * types there no concurrency is implied.
+ *
+ * Once concurrency is desired, more attributes must be observed:
+ * To start with, since some interface types are purely managed in
+ * software, like the AP-VLAN type in mac80211 for example, there's
+ * an additional list of these, they can be added at any time and
+ * are only restricted by some semantic restrictions (e.g. AP-VLAN
+ * cannot be added without a corresponding AP interface). This list
+ * is exported in the %NL80211_ATTR_SOFTWARE_IFTYPES attribute.
+ *
+ * Further, the list of supported combinations is exported. This is
+ * in the %NL80211_ATTR_INTERFACE_COMBINATIONS attribute. Basically,
+ * it exports a list of "groups", and at any point in time the
+ * interfaces that are currently active must fall into any one of
+ * the advertised groups. Within each group, there are restrictions
+ * on the number of interfaces of different types that are supported
+ * and also the number of different channels, along with potentially
+ * some other restrictions. See &enum nl80211_if_combination_attrs.
+ *
+ * All together, these attributes define the concurrency of virtual
+ * interfaces that a given device supports.
+ */
+
+/**
  * enum nl80211_commands - supported nl80211 commands
  *
  * @NL80211_CMD_UNSPEC: unspecified command to catch errors
@@ -954,6 +987,14 @@ enum nl80211_commands {
  * @NL80211_ATTR_SCHED_SCAN_INTERVAL: Interval between scheduled scan
  *      cycles, in msecs.
  *
+ * @NL80211_ATTR_INTERFACE_COMBINATIONS: Nested attribute listing the supported
+ *      interface combinations. In each nested item, it contains attributes
+ *      defined in &enum nl80211_if_combination_attrs.
+ * @NL80211_ATTR_SOFTWARE_IFTYPES: Nested attribute (just like
+ *      %NL80211_ATTR_SUPPORTED_IFTYPES) containing the interface types that
+ *      are managed in software: interfaces of these types aren't subject to
+ *      any restrictions in their number or combinations.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -1149,6 +1190,9 @@ enum nl80211_attrs {
 
         NL80211_ATTR_SCHED_SCAN_INTERVAL,
 
+        NL80211_ATTR_INTERFACE_COMBINATIONS,
+        NL80211_ATTR_SOFTWARE_IFTYPES,
+
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
@@ -1201,7 +1245,9 @@ enum nl80211_attrs {
  * @NL80211_IFTYPE_ADHOC: independent BSS member
  * @NL80211_IFTYPE_STATION: managed BSS member
  * @NL80211_IFTYPE_AP: access point
- * @NL80211_IFTYPE_AP_VLAN: VLAN interface for access points
+ * @NL80211_IFTYPE_AP_VLAN: VLAN interface for access points; VLAN interfaces
+ *      are a bit special in that they must always be tied to a pre-existing
+ *      AP type interface.
  * @NL80211_IFTYPE_WDS: wireless distribution interface
  * @NL80211_IFTYPE_MONITOR: monitor interface receiving all frames
  * @NL80211_IFTYPE_MESH_POINT: mesh point
@@ -2206,4 +2252,78 @@ enum nl80211_wowlan_triggers {
         MAX_NL80211_WOWLAN_TRIG = NUM_NL80211_WOWLAN_TRIG - 1
 };
 
+/**
+ * enum nl80211_iface_limit_attrs - limit attributes
+ * @NL80211_IFACE_LIMIT_UNSPEC: (reserved)
+ * @NL80211_IFACE_LIMIT_MAX: maximum number of interfaces that
+ *      can be chosen from this set of interface types (u32)
+ * @NL80211_IFACE_LIMIT_TYPES: nested attribute containing a
+ *      flag attribute for each interface type in this set
+ * @NUM_NL80211_IFACE_LIMIT: number of attributes
+ * @MAX_NL80211_IFACE_LIMIT: highest attribute number
+ */
+enum nl80211_iface_limit_attrs {
+        NL80211_IFACE_LIMIT_UNSPEC,
+        NL80211_IFACE_LIMIT_MAX,
+        NL80211_IFACE_LIMIT_TYPES,
+
+        /* keep last */
+        NUM_NL80211_IFACE_LIMIT,
+        MAX_NL80211_IFACE_LIMIT = NUM_NL80211_IFACE_LIMIT - 1
+};
+
+/**
+ * enum nl80211_if_combination_attrs -- interface combination attributes
+ *
+ * @NL80211_IFACE_COMB_UNSPEC: (reserved)
+ * @NL80211_IFACE_COMB_LIMITS: Nested attributes containing the limits
+ *      for given interface types, see &enum nl80211_iface_limit_attrs.
+ * @NL80211_IFACE_COMB_MAXNUM: u32 attribute giving the total number of
+ *      interfaces that can be created in this group. This number doesn't
+ *      apply to interfaces purely managed in software, which are listed
+ *      in a separate attribute %NL80211_ATTR_INTERFACES_SOFTWARE.
+ * @NL80211_IFACE_COMB_STA_AP_BI_MATCH: flag attribute specifying that
+ *      beacon intervals within this group must be all the same even for
+ *      infrastructure and AP/GO combinations, i.e. the GO(s) must adopt
+ *      the infrastructure network's beacon interval.
+ * @NL80211_IFACE_COMB_NUM_CHANNELS: u32 attribute specifying how many
+ *      different channels may be used within this group.
+ * @NUM_NL80211_IFACE_COMB: number of attributes
+ * @MAX_NL80211_IFACE_COMB: highest attribute number
+ *
+ * Examples:
+ *      limits = [ #{STA} <= 1, #{AP} <= 1 ], matching BI, channels = 1, max = 2
+ *      => allows an AP and a STA that must match BIs
+ *
+ *      numbers = [ #{AP, P2P-GO} <= 8 ], channels = 1, max = 8
+ *      => allows 8 of AP/GO
+ *
+ *      numbers = [ #{STA} <= 2 ], channels = 2, max = 2
+ *      => allows two STAs on different channels
+ *
+ *      numbers = [ #{STA} <= 1, #{P2P-client,P2P-GO} <= 3 ], max = 4
+ *      => allows a STA plus three P2P interfaces
+ *
+ * The list of these four possiblities could completely be contained
+ * within the %NL80211_ATTR_INTERFACE_COMBINATIONS attribute to indicate
+ * that any of these groups must match.
+ *
+ * "Combinations" of just a single interface will not be listed here,
+ * a single interface of any valid interface type is assumed to always
+ * be possible by itself. This means that implicitly, for each valid
+ * interface type, the following group always exists:
+ *      numbers = [ #{<type>} <= 1 ], channels = 1, max = 1
+ */
+enum nl80211_if_combination_attrs {
+        NL80211_IFACE_COMB_UNSPEC,
+        NL80211_IFACE_COMB_LIMITS,
+        NL80211_IFACE_COMB_MAXNUM,
+        NL80211_IFACE_COMB_STA_AP_BI_MATCH,
+        NL80211_IFACE_COMB_NUM_CHANNELS,
+
+        /* keep last */
+        NUM_NL80211_IFACE_COMB,
+        MAX_NL80211_IFACE_COMB = NUM_NL80211_IFACE_COMB - 1
+};
+
 #endif /* __LINUX_NL80211_H */
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index e1f1b41f7b13..04afcfb9eaf4 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1547,6 +1547,10 @@ struct cfg80211_ops {
  *      hints read the documenation for regulatory_hint_found_beacon()
  * @WIPHY_FLAG_NETNS_OK: if not set, do not allow changing the netns of this
  *      wiphy at all
+ * @WIPHY_FLAG_ENFORCE_COMBINATIONS: Set this flag to enforce interface
+ *      combinations for this device. This flag is used for backward
+ *      compatibility only until all drivers advertise combinations and
+ *      they will always be enforced.
  * @WIPHY_FLAG_PS_ON_BY_DEFAULT: if set to true, powersave will be enabled
  *      by default -- this flag will be set depending on the kernel's default
  *      on wiphy_new(), but can be changed by the driver if it has a good
@@ -1574,6 +1578,81 @@ enum wiphy_flags {
         WIPHY_FLAG_IBSS_RSN                     = BIT(8),
         WIPHY_FLAG_MESH_AUTH                    = BIT(10),
         WIPHY_FLAG_SUPPORTS_SCHED_SCAN          = BIT(11),
+        WIPHY_FLAG_ENFORCE_COMBINATIONS         = BIT(12),
+};
+
+/**
+ * struct ieee80211_iface_limit - limit on certain interface types
+ * @max: maximum number of interfaces of these types
+ * @types: interface types (bits)
+ */
+struct ieee80211_iface_limit {
+        u16 max;
+        u16 types;
+};
+
+/**
+ * struct ieee80211_iface_combination - possible interface combination
+ * @limits: limits for the given interface types
+ * @n_limits: number of limitations
+ * @num_different_channels: can use up to this many different channels
+ * @max_interfaces: maximum number of interfaces in total allowed in this
+ *      group
+ * @beacon_int_infra_match: In this combination, the beacon intervals
+ *      between infrastructure and AP types must match. This is required
+ *      only in special cases.
+ *
+ * These examples can be expressed as follows:
+ *
+ * Allow #STA <= 1, #AP <= 1, matching BI, channels = 1, 2 total:
+ *
+ *  struct ieee80211_iface_limit limits1[] = {
+ *      { .max = 1, .types = BIT(NL80211_IFTYPE_STATION), },
+ *      { .max = 1, .types = BIT(NL80211_IFTYPE_AP}, },
+ *  };
+ *  struct ieee80211_iface_combination combination1 = {
+ *      .limits = limits1,
+ *      .n_limits = ARRAY_SIZE(limits1),
+ *      .max_interfaces = 2,
+ *      .beacon_int_infra_match = true,
+ *  };
+ *
+ *
+ * Allow #{AP, P2P-GO} <= 8, channels = 1, 8 total:
+ *
+ *  struct ieee80211_iface_limit limits2[] = {
+ *      { .max = 8, .types = BIT(NL80211_IFTYPE_AP) |
+ *                           BIT(NL80211_IFTYPE_P2P_GO), },
+ *  };
+ *  struct ieee80211_iface_combination combination2 = {
+ *      .limits = limits2,
+ *      .n_limits = ARRAY_SIZE(limits2),
+ *      .max_interfaces = 8,
+ *      .num_different_channels = 1,
+ *  };
+ *
+ *
+ * Allow #STA <= 1, #{P2P-client,P2P-GO} <= 3 on two channels, 4 total.
+ * This allows for an infrastructure connection and three P2P connections.
+ *
+ *  struct ieee80211_iface_limit limits3[] = {
+ *      { .max = 1, .types = BIT(NL80211_IFTYPE_STATION), },
+ *      { .max = 3, .types = BIT(NL80211_IFTYPE_P2P_GO) |
+ *                           BIT(NL80211_IFTYPE_P2P_CLIENT), },
+ *  };
+ *  struct ieee80211_iface_combination combination3 = {
+ *      .limits = limits3,
+ *      .n_limits = ARRAY_SIZE(limits3),
+ *      .max_interfaces = 4,
+ *      .num_different_channels = 2,
+ *  };
+ */
+struct ieee80211_iface_combination {
+        const struct ieee80211_iface_limit *limits;
+        u32 num_different_channels;
+        u16 max_interfaces;
+        u8 n_limits;
+        bool beacon_int_infra_match;
 };
 
 struct mac_address {
@@ -1653,6 +1732,11 @@ struct wiphy_wowlan_support {
  * @priv: driver private data (sized according to wiphy_new() parameter)
  * @interface_modes: bitmask of interfaces types valid for this wiphy,
  *      must be set by driver
+ * @iface_combinations: Valid interface combinations array, should not
+ *      list single interface types.
+ * @n_iface_combinations: number of entries in @iface_combinations array.
+ * @software_iftypes: bitmask of software interface types, these are not
+ *      subject to any restrictions since they are purely managed in SW.
  * @flags: wiphy flags, see &enum wiphy_flags
  * @bss_priv_size: each BSS struct has private data allocated with it,
  *      this variable determines its size
@@ -1697,6 +1781,10 @@ struct wiphy {
 
         const struct ieee80211_txrx_stypes *mgmt_stypes;
 
+        const struct ieee80211_iface_combination *iface_combinations;
+        int n_iface_combinations;
+        u16 software_iftypes;
+
         u16 n_addresses;
 
         /* Supported interface modes, OR together BIT(NL80211_IFTYPE_...) */