Return-path: Received: from mail-bw0-f227.google.com ([209.85.218.227]:35101 "EHLO mail-bw0-f227.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751258AbZKJJs3 (ORCPT ); Tue, 10 Nov 2009 04:48:29 -0500 Received: by bwz27 with SMTP id 27so4338921bwz.21 for ; Tue, 10 Nov 2009 01:48:34 -0800 (PST) Date: Tue, 10 Nov 2009 10:48:01 +0100 Message-ID: From: Holger Schurig To: linux-wireless Cc: Johannes Berg Subject: [RFC] cfg80211: survey report capability MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-wireless-owner@vger.kernel.org List-ID: [RFC] cfg80211: first stab at channel survey This patch implements the NL80211_CMD_GET_SURVEY command and an get_survey() ops that a driver can implement. The goal of this command is to allow a driver to report back channel survey data (e.g. channel noise, channel occupation) back to cfg80211 and thus via nl80211 to user-space. In future, they will either be a survey-trigger command --- or the existing scan-trigger command will be enhanced. However, the get_survey() operation is usable even in absence of this: a driver can report the channel noise in mBm with the implemented mechanism. get_survey() is currently modelled like get_key(). I hope that's right. struct survey_info is modelled like struct station_info. This allows different drivers to fill in different fields. Signed-off-by: Holger Schurig --- linux-wl.orig/include/linux/nl80211.h +++ linux-wl/include/linux/nl80211.h @@ -159,6 +159,8 @@ * NL80211_CMD_GET_SCAN and on the "scan" multicast group) * @NL80211_CMD_SCAN_ABORTED: scan was aborted, for unspecified reasons, * partial scan results may be available + * @NL80211_CMD_GET_SURVEY: get survey resuls, e.g. channel occupation + * or noise level * * @NL80211_CMD_REG_CHANGE: indicates to userspace the regulatory domain * has been changed and provides details of the request information @@ -341,6 +343,8 @@ NL80211_CMD_SET_WIPHY_NETNS, + NL80211_CMD_GET_SURVEY, + /* add new commands above here */ /* used to define NL80211_CMD_MAX below */ @@ -584,6 +588,8 @@ * changed then the list changed and the dump should be repeated * completely from scratch. * + * @NL80211_CHANNEL_NOISE: Noise on channel in mBm + * * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use */ @@ -714,6 +720,8 @@ NL80211_ATTR_PID, + NL80211_ATTR_NOISE, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, --- linux-wl.orig/include/net/cfg80211.h +++ linux-wl/include/net/cfg80211.h @@ -232,6 +232,35 @@ u32 cipher; }; +/** enum survey_info_flags - survey information flags + * + * Used by the driver to indicate which info in &struct survey_info + * it has filled in during the get_survey(). + */ +enum survey_info_flags { + SURVEY_INFO_CHANNEL = 1<<0, + SURVEY_INFO_NOISE = 1<<1, +}; + +/** + * struct survey_info - channel survey response + * + * Used from the get_survey() callback to report back + * per-channel survey information. + * + * @filled: bitflag of flags from &enum survey_info_flags + * @noise: channel noise in mBm + * @channel: the channel this survey record reports + * + * This structure can later be expanded with things like + * channel duty cycles etc. + */ +struct survey_info { + u32 filled; + struct ieee80211_channel *channel; + s8 noise; +}; + /** * struct beacon_parameters - beacon parameters * @@ -941,6 +970,8 @@ * @rfkill_poll: polls the hw rfkill line, use cfg80211 reporting * functions to adjust rfkill hw state * + * @get_survey: get site survey information about. + * * @testmode_cmd: run a test mode command */ struct cfg80211_ops { @@ -1060,6 +1091,10 @@ const u8 *peer, const struct cfg80211_bitrate_mask *mask); + int (*get_survey)(struct wiphy *wiphy, struct net_device *netdev, + void *cookie, + void (*callback)(void *cookie, struct survey_info*)); + /* some temporary stuff to finish wext */ int (*set_power_mgmt)(struct wiphy *wiphy, struct net_device *dev, bool enabled, int timeout); --- linux-wl.orig/net/wireless/nl80211.c +++ linux-wl/net/wireless/nl80211.c @@ -3238,6 +3238,155 @@ return err; } +struct get_survey_cookie { + struct sk_buff *msg; + int error; +}; + +static void get_survey_callback(void *c, struct survey_info *params) +{ + struct get_survey_cookie *cookie = c; + + if (params->filled & SURVEY_INFO_CHANNEL) + if (nl80211_msg_put_channel(cookie->msg, params->channel)) + goto nla_put_failure; + + if (params->filled & SURVEY_INFO_NOISE) + NLA_PUT_U32(cookie->msg, NL80211_ATTR_NOISE, + params->noise); + + nla_put_failure: + cookie->error = 1; +} + +static int nl80211_get_survey(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *rdev; + struct net_device *dev; + struct get_key_cookie cookie = { + .error = 0, + }; + int err; + void *hdr; + struct sk_buff *msg; + + rtnl_lock(); + + err = get_rdev_dev_by_info_ifindex(info, &rdev, &dev); + if (err) + goto unlock_rtnl; + + if (!rdev->ops->get_survey) { + err = -EOPNOTSUPP; + goto out; + } + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) { + err = -ENOMEM; + goto out; + } + + hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0, + NL80211_CMD_NEW_KEY); + + if (IS_ERR(hdr)) { + err = PTR_ERR(hdr); + goto free_msg; + } + + cookie.msg = msg; + + NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex); + + err = rdev->ops->get_survey(&rdev->wiphy, dev, &cookie, + get_survey_callback); + + if (err) + goto free_msg; + + if (cookie.error) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + err = genlmsg_reply(msg, info); + goto out; + + nla_put_failure: + err = -ENOBUFS; + free_msg: + nlmsg_free(msg); + out: + cfg80211_unlock_rdev(rdev); + dev_put(dev); + unlock_rtnl: + rtnl_unlock(); + + return err; + +/* + if (!ifidx) { + err = nlmsg_parse(cb->nlh, GENL_HDRLEN + nl80211_fam.hdrsize, + nl80211_fam.attrbuf, nl80211_fam.maxattr, + nl80211_policy); + if (err) + return err; + + if (!nl80211_fam.attrbuf[NL80211_ATTR_IFINDEX]) + return -EINVAL; + + ifidx = nla_get_u32(nl80211_fam.attrbuf[NL80211_ATTR_IFINDEX]); + if (!ifidx) + return -EINVAL; + cb->args[0] = ifidx; + } + + dev = dev_get_by_index(sock_net(skb->sk), ifidx); + if (!dev) + return -ENODEV; + + rdev = cfg80211_get_dev_from_ifindex(sock_net(skb->sk), ifidx); + if (IS_ERR(rdev)) { + err = PTR_ERR(rdev); + goto out_put_netdev; + } + + wdev = dev->ieee80211_ptr; + + wdev_lock(wdev); + //TODO + + void *hdr; + int i; + + ASSERT_WDEV_LOCK(wdev); + + hdr = nl80211hdr_put(msg, pid, seq, flags, + NL80211_CMD_NEW_SCAN_RESULTS); + if (!hdr) + return -1; + + + return genlmsg_end(msg, hdr); + + nla_put_failure: + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; + + + //TODO + wdev_unlock(wdev); + + cb->args[1] = idx; + err = skb->len; + cfg80211_unlock_rdev(rdev); + out_put_netdev: + dev_put(dev); + + return err; +*/ +} + static bool nl80211_valid_auth_type(enum nl80211_auth_type auth_type) { return auth_type <= NL80211_AUTHTYPE_MAX; @@ -4315,6 +4464,11 @@ .policy = nl80211_policy, .flags = GENL_ADMIN_PERM, }, + { + .cmd = NL80211_CMD_GET_SURVEY, + .doit = nl80211_get_survey, + .policy = nl80211_policy, + }, }; static struct genl_multicast_group nl80211_mlme_mcgrp = { .name = "mlme", -- http://www.holgerschurig.de