[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 <holgerschurig@xxxxxxxxx>
--- 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
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
