Add ACS offload to let the device select a channel for AP from a list of channels that the user-space provides. ACS can customize the method of AP channel selection and add parameters like traffic load, number of APs on channel and more.
Change-Id: I18cb8460b9418512ac7ac9f76fe8f7f379f2478b Signed-off-by: Ahmad Masri <[email protected]> --- include/net/cfg80211.h | 33 ++++++++ include/uapi/linux/nl80211.h | 65 ++++++++++++++++ net/wireless/mlme.c | 31 ++++++++ net/wireless/nl80211.c | 182 +++++++++++++++++++++++++++++++++++++++++++ net/wireless/nl80211.h | 6 ++ net/wireless/rdev-ops.h | 12 +++ net/wireless/trace.h | 23 ++++++ 7 files changed, 352 insertions(+) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index ede7fcd..c3faa48 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -715,6 +715,17 @@ struct survey_info { s8 noise; }; +/** + * struct cfg80211_acs_params - ACS parameters + * @n_channels: total number of channels for ACS + * @channels: list of chan_def to run ACS on + */ +struct cfg80211_acs_params { + u32 n_channels; + /* keep last */ + struct cfg80211_chan_def channels[0]; +}; + #define CFG80211_MAX_WEP_KEYS 4 /** @@ -3377,6 +3388,11 @@ struct cfg80211_pmsr_request { * Statistics should be cumulative, currently no way to reset is provided. * @start_pmsr: start peer measurement (e.g. FTM) * @abort_pmsr: abort peer measurement + * @acs: run automatic channel selection offload measurement to find the best + * channel to start the AP on. Userspace provide a list of chan_defs, the + * driver should perform ACS on the provided list and select best channel. + * driver should call cfg80211_acs_result to complete this operation. + * (invoked with the wireless_dev mutex held) */ struct cfg80211_ops { int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow); @@ -3691,6 +3707,8 @@ struct cfg80211_ops { struct cfg80211_pmsr_request *request); void (*abort_pmsr)(struct wiphy *wiphy, struct wireless_dev *wdev, struct cfg80211_pmsr_request *request); + int (*acs)(struct wiphy *wiphy, struct net_device *dev, + struct cfg80211_acs_params *params); }; /* @@ -4662,6 +4680,7 @@ struct wireless_dev { unsigned long cac_start_time; unsigned int cac_time_ms; + bool acs_started; #ifdef CONFIG_CFG80211_WEXT /* wext data */ struct { @@ -6362,6 +6381,20 @@ void cfg80211_cac_event(struct net_device *netdev, /** + * cfg80211_acs_result - ACS result notification + * @netdev: network device + * @chandef: chandef for the selected channel, NULL on unsuccessful operation + * @status: ACS status as specified in &enum nl80211_acs_status + * @gfp: context flags + * + * This function is called when ACS measurement is finished or aborted. + * This must be called to notify the completion of a ACS process. + */ +void cfg80211_acs_result(struct net_device *netdev, + const struct cfg80211_chan_def *chandef, + enum nl80211_acs_status status, gfp_t gfp); + +/** * cfg80211_gtk_rekey_notify - notify userspace about driver rekeying * @dev: network device * @bssid: BSSID of AP (to avoid races) diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index 2b53c0e..b993b86f 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -1032,6 +1032,13 @@ * ht opmode or vht opmode changes using any of %NL80211_ATTR_SMPS_MODE, * %NL80211_ATTR_CHANNEL_WIDTH,%NL80211_ATTR_NSS attributes with its * address(specified in %NL80211_ATTR_MAC). + * @NL80211_CMD_ACS: For offloaded Automatic Channel Selection (ACS). Userspace + * sends this command before starting an AP, the kernel indicates this + * command after a channel was selected. When sent from userspace has + * attribute NL80211_ATTR_CHAN_DEF for a list of channels (chan_def). + * When sent from kernel has attributes NL80211_ATTR_ACS_STATUS which + * provides the operation status and NL80211_ATTR_WIPHY_FREQ and other + * chan_def attributes which describes the chosen channel. * * @NL80211_CMD_GET_FTM_RESPONDER_STATS: Retrieve FTM responder statistics, in * the %NL80211_ATTR_FTM_RESPONDER_STATS attribute. @@ -1277,6 +1284,7 @@ enum nl80211_commands { NL80211_CMD_PEER_MEASUREMENT_START, NL80211_CMD_PEER_MEASUREMENT_RESULT, NL80211_CMD_PEER_MEASUREMENT_COMPLETE, + NL80211_CMD_ACS, /* add new commands above here */ @@ -2273,6 +2281,13 @@ enum nl80211_commands { * @NL80211_ATTR_HE_CAPABILITY: HE Capability information element (from * association request when used with NL80211_CMD_NEW_STATION). Can be set * only if %NL80211_STA_FLAG_WME is set. + * @NL80211_ATTR_ACS_STATUS: attribute in which kernel indicates ACS status + * as defined in &enum nl80211_acs_status + * @NL80211_ATTR_CHAN_DEF: attribute for nesting chan_def parameters + * as defined in &enum nl80211_ch_def_attr. The new attribute allows + * userspace to send a list of struct cfg80211_chan_def. For example, ACS + * command uses this attribute for sending a list of channels, for more + * details see &NL80211_CMD_ACS. * * @NL80211_ATTR_FTM_RESPONDER: nested attribute which user-space can include * in %NL80211_CMD_START_AP or %NL80211_CMD_SET_BEACON for fine timing @@ -2741,6 +2756,9 @@ enum nl80211_attrs { NL80211_ATTR_PEER_MEASUREMENTS, + NL80211_ATTR_ACS_STATUS, + NL80211_ATTR_CHAN_DEF, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, @@ -4548,6 +4566,35 @@ enum nl80211_packet_pattern_attr { }; /** + * enum nl80211_ch_def_attr - channel def attribute + * @__NL80211_ATTR_CH_DEF_INVALID: invalid number for nested attribute + * @NL80211_ATTR_CH_DEF_FREQ: frequency of the selected channel in MHz, + * defines the channel together with the attributes + * %NL80211_ATTR_CH_DEF_WIDTH and if needed %NL80211_ATTR_CH_DEF_FREQ1 and + * %NL80211_ATTR_CH_DEF_FREQ2 + * @NL80211_ATTR_CH_DEF_WIDTH: u32 attribute containing one of the values + * of &enum nl80211_chan_width, describing the channel width. See the + * documentation of the enum for more information. + * @NL80211_ATTR_CH_DEF_FREQ1: Center frequency of the first part of the + * channel, used for anything but 20 MHz bandwidth + * @NL80211_ATTR_CH_DEF_FREQ2: Center frequency of the second part of the + * channel, used only for 80+80 MHz bandwidth + * @__NL80211_ATTR_CH_DEF_AFTER_LAST: internal + * @NL80211_ATTR_CH_DEF_MAX: max attribute number + */ +enum nl80211_ch_def_attr { + __NL80211_ATTR_CH_DEF_INVALID, + NL80211_ATTR_CH_DEF_FREQ, + NL80211_ATTR_CH_DEF_WIDTH, + NL80211_ATTR_CH_DEF_FREQ1, + NL80211_ATTR_CH_DEF_FREQ2, + + /* keep last */ + __NL80211_ATTR_CH_DEF_AFTER_LAST, + NL80211_ATTR_CH_DEF_MAX = __NL80211_ATTR_CH_DEF_AFTER_LAST - 1 +}; + +/** * struct nl80211_pattern_support - packet pattern support information * @max_patterns: maximum number of patterns supported * @min_pattern_len: minimum length of each pattern @@ -5308,6 +5355,8 @@ enum nl80211_feature_flags { * able to rekey an in-use key correctly. Userspace must not rekey PTK keys * if this flag is not set. Ignoring this can leak clear text packets and/or * freeze the connection. + * @NL80211_EXT_FEATURE_ACS_OFFLOAD: The driver supports offload of ACS from + * a list of channels provided by the userspace. * * @NUM_NL80211_EXT_FEATURES: number of extended features. * @MAX_NL80211_EXT_FEATURES: highest extended feature index. @@ -5348,6 +5397,7 @@ enum nl80211_ext_feature_index { NL80211_EXT_FEATURE_SCAN_MIN_PREQ_CONTENT, NL80211_EXT_FEATURE_CAN_REPLACE_PTK0, NL80211_EXT_FEATURE_ENABLE_FTM_RESPONDER, + NL80211_EXT_FEATURE_ACS_OFFLOAD, /* add new features before the definition below */ NUM_NL80211_EXT_FEATURES, @@ -5561,6 +5611,21 @@ enum nl80211_dfs_state { }; /** + * enum nl80211_acs_status - ACS status + * + * status to be used to inform userspace about the result of the ACS offloaded + * measurement. + * + * @NL80211_ACS_SUCCESS: The ACS operation finished successfully + * @NL80211_ACS_FAILED: Failed to run the ACS. Userspace should choose a channel + * by itself. + */ +enum nl80211_acs_status { + NL80211_ACS_SUCCESS, + NL80211_ACS_FAILED, +}; + +/** * enum enum nl80211_protocol_features - nl80211 protocol features * @NL80211_PROTOCOL_FEATURE_SPLIT_WIPHY_DUMP: nl80211 supports splitting * wiphy dumps (if requested by the application with the attribute diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c index 1615e50..ed36d91 100644 --- a/net/wireless/mlme.c +++ b/net/wireless/mlme.c @@ -903,3 +903,34 @@ void cfg80211_cac_event(struct net_device *netdev, nl80211_radar_notify(rdev, chandef, event, netdev, gfp); } EXPORT_SYMBOL(cfg80211_cac_event); + +void cfg80211_acs_result(struct net_device *netdev, + const struct cfg80211_chan_def *chandef, + enum nl80211_acs_status status, gfp_t gfp) +{ + struct wireless_dev *wdev = netdev->ieee80211_ptr; + struct wiphy *wiphy = wdev->wiphy; + struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); + + if (WARN_ON(!wdev->acs_started)) + return; + + switch (status) { + case NL80211_ACS_SUCCESS: + if (!chandef) { + WARN_ON(1); + goto out; + } + case NL80211_ACS_FAILED: + break; + default: + WARN_ON(1); + goto out; + } + nl80211_acs_notify(rdev, chandef, status, netdev, gfp); + +out: + wdev->acs_started = false; + dev_put(netdev); +} +EXPORT_SYMBOL(cfg80211_acs_result); diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 5ec200e..bf25824 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -557,6 +557,8 @@ static int validate_ie_attr(const struct nlattr *attr, [NL80211_ATTR_PEER_MEASUREMENTS] = NLA_POLICY_NESTED(NL80211_PMSR_FTM_REQ_ATTR_MAX, nl80211_pmsr_attr_policy), + + [NL80211_ATTR_CHAN_DEF] = { .type = NLA_NESTED }, }; /* policy for the key attributes */ @@ -697,6 +699,15 @@ static int validate_ie_attr(const struct nlattr *attr, [NL80211_PKTPAT_OFFSET] = { .type = NLA_U32 }, }; +/* policy for channel attributes */ +static const struct nla_policy +nl80211_ch_def_policy[NL80211_ATTR_CH_DEF_MAX + 1] = { + [NL80211_ATTR_CH_DEF_FREQ] = { .type = NLA_U32 }, + [NL80211_ATTR_CH_DEF_WIDTH] = { .type = NLA_U32 }, + [NL80211_ATTR_CH_DEF_FREQ1] = { .type = NLA_U32 }, + [NL80211_ATTR_CH_DEF_FREQ2] = { .type = NLA_U32 }, +}; + int nl80211_prepare_wdev_dump(struct netlink_callback *cb, struct cfg80211_registered_device **rdev, struct wireless_dev **wdev) @@ -2561,6 +2572,66 @@ int nl80211_parse_chandef(struct cfg80211_registered_device *rdev, return 0; } +static int +nl80211_parse_chandef_new(struct cfg80211_registered_device *rdev, + struct genl_info *info, struct nlattr *channel, + struct cfg80211_chan_def *chandef) +{ + u32 control_freq; + struct nlattr *attrs[NL80211_ATTR_CH_DEF_MAX + 1]; + int err; + + if (!channel) + return -EINVAL; + + err = nla_parse_nested(attrs, NL80211_ATTR_CH_DEF_MAX, channel, + nl80211_ch_def_policy, info->extack); + if (err) + return err; + + + if (!attrs[NL80211_ATTR_CH_DEF_FREQ]) + return -EINVAL; + + control_freq = nla_get_u32(attrs[NL80211_ATTR_CH_DEF_FREQ]); + + chandef->chan = ieee80211_get_channel(&rdev->wiphy, control_freq); + chandef->width = NL80211_CHAN_WIDTH_20_NOHT; + chandef->center_freq1 = control_freq; + chandef->center_freq2 = 0; + + /* Primary channel not allowed */ + if (!chandef->chan || chandef->chan->flags & IEEE80211_CHAN_DISABLED) + return -EINVAL; + + if (attrs[NL80211_ATTR_CH_DEF_WIDTH]) { + chandef->width = + nla_get_u32(attrs[NL80211_ATTR_CH_DEF_WIDTH]); + if (attrs[NL80211_ATTR_CH_DEF_FREQ1]) + chandef->center_freq1 = + nla_get_u32( + attrs[NL80211_ATTR_CH_DEF_FREQ1]); + if (attrs[NL80211_ATTR_CH_DEF_FREQ2]) + chandef->center_freq2 = + nla_get_u32( + attrs[NL80211_ATTR_CH_DEF_FREQ2]); + } + + if (!cfg80211_chandef_valid(chandef)) + return -EINVAL; + + if (!cfg80211_chandef_usable(&rdev->wiphy, chandef, + IEEE80211_CHAN_DISABLED)) + return -EINVAL; + + if ((chandef->width == NL80211_CHAN_WIDTH_5 || + chandef->width == NL80211_CHAN_WIDTH_10) && + !(rdev->wiphy.flags & WIPHY_FLAG_SUPPORTS_5_10_MHZ)) + return -EINVAL; + + return 0; +} + static int __nl80211_set_channel(struct cfg80211_registered_device *rdev, struct net_device *dev, struct genl_info *info) @@ -13140,6 +13211,71 @@ static int nl80211_get_ftm_responder_stats(struct sk_buff *skb, return -ENOBUFS; } +static int nl80211_acs(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *rdev = info->user_ptr[0]; + struct net_device *dev = info->user_ptr[1]; + struct wireless_dev *wdev = dev->ieee80211_ptr; + struct cfg80211_acs_params *request; + struct nlattr *attr; + struct wiphy *wiphy; + int ret, tmp, n_channels = 0, i = 0; + + if (WARN_ON(wdev->acs_started)) + return -EALREADY; + + if (!rdev->ops->acs) + return -EOPNOTSUPP; + + if (wdev->iftype != NL80211_IFTYPE_AP) + return -EOPNOTSUPP; + + wiphy = &rdev->wiphy; + + if (!info->attrs[NL80211_ATTR_CHAN_DEF]) + return -EINVAL; + + nla_for_each_nested(attr, + info->attrs[NL80211_ATTR_CHAN_DEF], tmp) + n_channels++; + + if (!n_channels) + return -EINVAL; + + request = kzalloc(sizeof(*request) + + sizeof(struct cfg80211_chan_def) * n_channels, + GFP_KERNEL); + if (!request) + return -ENOMEM; + + nla_for_each_nested(attr, + info->attrs[NL80211_ATTR_CHAN_DEF], tmp) { + struct cfg80211_chan_def chandef; + + ret = nl80211_parse_chandef_new(rdev, info, attr, &chandef); + if (ret) + goto out_free; + + request->channels[i++] = chandef; + } + request->n_channels = i; + + wdev->acs_started = true; + dev_hold(dev); + + wdev_lock(wdev); + ret = rdev_acs(rdev, dev, request); + if (ret) { + wdev->acs_started = false; + dev_put(dev); + } + wdev_unlock(wdev); + + out_free: + kfree(request); + return ret; +} + #define NL80211_FLAG_NEED_WIPHY 0x01 #define NL80211_FLAG_NEED_NETDEV 0x02 #define NL80211_FLAG_NEED_RTNL 0x04 @@ -14066,6 +14202,15 @@ static void nl80211_post_doit(const struct genl_ops *ops, struct sk_buff *skb, .internal_flags = NL80211_FLAG_NEED_WDEV_UP | NL80211_FLAG_NEED_RTNL, }, + { + .cmd = NL80211_CMD_ACS, + .doit = nl80211_acs, + .policy = nl80211_policy, + .flags = GENL_UNS_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, + }; static struct genl_family nl80211_fam __ro_after_init = { @@ -15656,6 +15801,43 @@ void cfg80211_ch_switch_started_notify(struct net_device *dev, nlmsg_free(msg); } +void +nl80211_acs_notify(struct cfg80211_registered_device *rdev, + const struct cfg80211_chan_def *chandef, + enum nl80211_acs_status status, + struct net_device *netdev, gfp_t gfp) +{ + struct sk_buff *msg; + void *hdr; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + if (!msg) + return; + + hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_ACS); + if (!hdr) { + nlmsg_free(msg); + return; + } + + if (nla_put_u32(msg, NL80211_ATTR_ACS_STATUS, status)) + goto nla_put_failure; + + if (nl80211_send_chandef(msg, chandef)) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + + genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0, + NL80211_MCGRP_MLME, gfp); + + return; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + nlmsg_free(msg); +} + void cfg80211_sta_opmode_change_notify(struct net_device *dev, const u8 *mac, struct sta_opmode_info *sta_opmode, gfp_t gfp) diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h index 531c82d..e406592 100644 --- a/net/wireless/nl80211.h +++ b/net/wireless/nl80211.h @@ -119,6 +119,12 @@ int nl80211_send_mgmt(struct cfg80211_registered_device *rdev, enum nl80211_radar_event event, struct net_device *netdev, gfp_t gfp); +void +nl80211_acs_notify(struct cfg80211_registered_device *rdev, + const struct cfg80211_chan_def *chandef, + enum nl80211_acs_status status, + struct net_device *netdev, gfp_t gfp); + void nl80211_send_ap_stopped(struct wireless_dev *wdev); void cfg80211_rdev_free_coalesce(struct cfg80211_registered_device *rdev); diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h index 5cb48d1..ebd9576 100644 --- a/net/wireless/rdev-ops.h +++ b/net/wireless/rdev-ops.h @@ -1272,4 +1272,16 @@ static inline int rdev_del_pmk(struct cfg80211_registered_device *rdev, trace_rdev_return_void(&rdev->wiphy); } +static inline int rdev_acs(struct cfg80211_registered_device *rdev, + struct net_device *dev, + struct cfg80211_acs_params *params) +{ + int ret; + + trace_rdev_acs(&rdev->wiphy, dev, params); + ret = rdev->ops->acs(&rdev->wiphy, dev, params); + trace_rdev_return_int(&rdev->wiphy, ret); + return ret; +} + #endif /* __CFG80211_RDEV_OPS */ diff --git a/net/wireless/trace.h b/net/wireless/trace.h index 44b2ce1..c841873 100644 --- a/net/wireless/trace.h +++ b/net/wireless/trace.h @@ -2530,6 +2530,29 @@ TP_ARGS(wiphy, wdev, cookie) ); +TRACE_EVENT(rdev_acs, + TP_PROTO(struct wiphy *wiphy, struct net_device *netdev, + struct cfg80211_acs_params *params), + + TP_ARGS(wiphy, netdev, params), + + TP_STRUCT__entry( + WIPHY_ENTRY + NETDEV_ENTRY + __field(u32, n_channels) + ), + + TP_fast_assign( + WIPHY_ASSIGN; + NETDEV_ASSIGN; + __entry->n_channels = params->n_channels; + ), + + TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT + ", num of channels: %u", WIPHY_PR_ARG, NETDEV_PR_ARG, + __entry->n_channels) +); + /************************************************************* * cfg80211 exported functions traces * *************************************************************/ -- 1.9.1
