This patch implements the idea to have multiple scheduled scan requests running concurrently. It mainly illustrates how to deal with the incoming request from user-space in terms of backward compatibility. In order to use multiple scheduled scans user-space needs to provide a flag attribute NL80211_ATTR_SCHED_SCAN_MULTI to indicate support. If not the request is treated as a legacy scan.
Cc: Dmitry Shmidt <[email protected]> Signed-off-by: Arend van Spriel <[email protected]> --- Hi Johannes, Did a bit of coding on the Universal/multi-scheduled scan idea. This just deals with handling requests. Not sure if I got the RCU stuff right so any remarks are welcome. Regards, Arend --- include/net/cfg80211.h | 7 ++++ include/uapi/linux/nl80211.h | 12 ++++++- net/wireless/core.c | 30 ++++++++++------ net/wireless/core.h | 10 +++++- net/wireless/nl80211.c | 38 ++++++++++++++++++-- net/wireless/scan.c | 83 +++++++++++++++++++++++++++++++++++--------- 6 files changed, 148 insertions(+), 32 deletions(-) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 814be4b..f5c0592 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1594,6 +1594,7 @@ struct cfg80211_sched_scan_plan { /** * struct cfg80211_sched_scan_request - scheduled scan request description * + * @reqid: identifies this request. * @ssids: SSIDs to scan for (passed in the probe_reqs in active scans) * @n_ssids: number of SSIDs * @n_channels: total number of channels to scan @@ -1622,12 +1623,14 @@ struct cfg80211_sched_scan_plan { * @rcu_head: RCU callback used to free the struct * @owner_nlportid: netlink portid of owner (if this should is a request * owned by a particular socket) + * @list: for keeping list of requests. * @delay: delay in seconds to use before starting the first scan * cycle. The driver may ignore this parameter and start * immediately (or at any other time), if this feature is not * supported. */ struct cfg80211_sched_scan_request { + u64 reqid; struct cfg80211_ssid *ssids; int n_ssids; u32 n_channels; @@ -1651,6 +1654,7 @@ struct cfg80211_sched_scan_request { unsigned long scan_start; struct rcu_head rcu_head; u32 owner_nlportid; + struct list_head list; /* keep last */ struct ieee80211_channel *channels[0]; @@ -3415,6 +3419,8 @@ struct wiphy_iftype_ext_capab { * this variable determines its size * @max_scan_ssids: maximum number of SSIDs the device can scan for in * any given scan + * @max_sched_scan_reqs: maximum number of scheduled scan requests that + * the device can run concurrently. * @max_sched_scan_ssids: maximum number of SSIDs the device can scan * for in any given scheduled scan * @max_match_sets: maximum number of match sets the device can handle @@ -3547,6 +3553,7 @@ struct wiphy { int bss_priv_size; u8 max_scan_ssids; + u8 max_sched_scan_reqs; u8 max_sched_scan_ssids; u8 max_match_sets; u16 max_scan_ie_len; diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index 6b76e3b..4045058 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -351,7 +351,9 @@ * are used. Extra IEs can also be passed from the userspace by * using the %NL80211_ATTR_IE attribute. The first cycle of the * scheduled scan can be delayed by %NL80211_ATTR_SCHED_SCAN_DELAY - * is supplied. + * is supplied. If the device supports multiple concurrent scheduled + * scans, it will allow such when the caller provides the flag attribute + * %NL80211_ATTR_SCHED_SCAN_MULTI to indicate user-space support for it. * @NL80211_CMD_STOP_SCHED_SCAN: stop a scheduled scan. Returns -ENOENT if * scheduled scan is not running. The caller may assume that as soon * as the call returns, it is safe to start a new scheduled scan again. @@ -1980,6 +1982,11 @@ enum nl80211_commands { * @NL80211_ATTR_BSSID: The BSSID of the AP. Note that %NL80211_ATTR_MAC is also * used in various commands/events for specifying the BSSID. * + * @NL80211_ATTR_SCHED_SCAN_MULTI: flag attribute which user-space shall use to + * indicate that it supports multiple active scheduled scan requests. + * @NL80211_ATTR_SCHED_SCAN_MAX_REQS: indicates maximum number of scheduled + * scan request that may be active for the device (u8). + * * @NUM_NL80211_ATTR: total number of nl80211_attrs available * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use @@ -2386,6 +2393,9 @@ enum nl80211_attrs { NL80211_ATTR_BSSID, + NL80211_ATTR_SCHED_SCAN_MULTI, + NL80211_ATTR_SCHED_SCAN_MAX_REQS, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, diff --git a/net/wireless/core.c b/net/wireless/core.c index 158c59e..1584234 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -346,13 +346,17 @@ static void cfg80211_destroy_iface_wk(struct work_struct *work) static void cfg80211_sched_scan_stop_wk(struct work_struct *work) { struct cfg80211_registered_device *rdev; + struct cfg80211_sched_scan_request *pos, *tmp; rdev = container_of(work, struct cfg80211_registered_device, sched_scan_stop_wk); rtnl_lock(); - __cfg80211_stop_sched_scan(rdev, false); + /* request gets removed from list so need safe iterator */ + list_for_each_entry_safe(pos, tmp, &rdev->sched_scan_req_list, list) { + cfg80211_stop_sched_scan_req(rdev, pos, false); + } rtnl_unlock(); } @@ -436,6 +440,7 @@ struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv, spin_lock_init(&rdev->beacon_registrations_lock); spin_lock_init(&rdev->bss_lock); INIT_LIST_HEAD(&rdev->bss_list); + INIT_LIST_HEAD(&rdev->sched_scan_req_list); INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done); INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results); INIT_LIST_HEAD(&rdev->mlme_unreg); @@ -690,6 +695,10 @@ int wiphy_register(struct wiphy *wiphy) (wiphy->bss_select_support & ~(BIT(__NL80211_BSS_SELECT_ATTR_AFTER_LAST) - 2)))) return -EINVAL; + if ((wiphy->flags & WIPHY_FLAG_SUPPORTS_SCHED_SCAN) && + !wiphy->max_sched_scan_reqs) + wiphy->max_sched_scan_reqs = 1; + if (wiphy->addresses) memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN); @@ -1000,7 +1009,7 @@ void __cfg80211_leave(struct cfg80211_registered_device *rdev, struct wireless_dev *wdev) { struct net_device *dev = wdev->netdev; - struct cfg80211_sched_scan_request *sched_scan_req; + struct cfg80211_sched_scan_request *pos, *tmp; ASSERT_RTNL(); ASSERT_WDEV_LOCK(wdev); @@ -1011,9 +1020,10 @@ void __cfg80211_leave(struct cfg80211_registered_device *rdev, break; case NL80211_IFTYPE_P2P_CLIENT: case NL80211_IFTYPE_STATION: - sched_scan_req = rtnl_dereference(rdev->sched_scan_req); - if (sched_scan_req && dev == sched_scan_req->dev) - __cfg80211_stop_sched_scan(rdev, false); + list_for_each_entry_safe(pos, tmp, &rdev->sched_scan_req_list, list) { + if (dev == pos->dev) + cfg80211_stop_sched_scan_req(rdev, pos, false); + } #ifdef CONFIG_CFG80211_WEXT kfree(wdev->wext.ie); @@ -1088,7 +1098,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct wireless_dev *wdev = dev->ieee80211_ptr; struct cfg80211_registered_device *rdev; - struct cfg80211_sched_scan_request *sched_scan_req; + struct cfg80211_sched_scan_request *pos, *tmp; if (!wdev) return NOTIFY_DONE; @@ -1155,10 +1165,10 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, ___cfg80211_scan_done(rdev, false); } - sched_scan_req = rtnl_dereference(rdev->sched_scan_req); - if (WARN_ON(sched_scan_req && - sched_scan_req->dev == wdev->netdev)) { - __cfg80211_stop_sched_scan(rdev, false); + list_for_each_entry_safe(pos, tmp, + &rdev->sched_scan_req_list, list) { + if (WARN_ON(pos && pos->dev == wdev->netdev)) + cfg80211_stop_sched_scan_req(rdev, pos, false); } rdev->opencount--; diff --git a/net/wireless/core.h b/net/wireless/core.h index 9820fa2..951954b 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -73,6 +73,8 @@ struct cfg80211_registered_device { u32 bss_generation; struct cfg80211_scan_request *scan_req; /* protected by RTNL */ struct sk_buff *scan_msg; + u8 sched_scan_req_count; + struct list_head sched_scan_req_list; struct cfg80211_sched_scan_request __rcu *sched_scan_req; unsigned long suspend_at; struct work_struct scan_done_wk; @@ -419,9 +421,15 @@ int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev, void __cfg80211_scan_done(struct work_struct *wk); void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool send_message); +void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev, + struct cfg80211_sched_scan_request *req); +bool cfg80211_legacy_sched_scan_active(struct cfg80211_registered_device *rdev); void __cfg80211_sched_scan_results(struct work_struct *wk); +int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev, + struct cfg80211_sched_scan_request *req, + bool driver_initiated); int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, - bool driver_initiated); + u64 reqid, bool driver_initiated); void cfg80211_upload_connect_keys(struct wireless_dev *wdev); int cfg80211_change_iface(struct cfg80211_registered_device *rdev, struct net_device *dev, enum nl80211_iftype ntype, diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 3df85a7..f1b253c 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -405,6 +405,7 @@ enum nl80211_multicast_groups { [NL80211_ATTR_FILS_NONCES] = { .len = 2 * FILS_NONCE_LEN }, [NL80211_ATTR_MULTICAST_TO_UNICAST_ENABLED] = { .type = NLA_FLAG, }, [NL80211_ATTR_BSSID] = { .len = ETH_ALEN }, + [NL80211_ATTR_SCHED_SCAN_MULTI] = { .type = NLA_FLAG }, }; /* policy for the key attributes */ @@ -1463,6 +1464,8 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev, rdev->wiphy.coverage_class) || nla_put_u8(msg, NL80211_ATTR_MAX_NUM_SCAN_SSIDS, rdev->wiphy.max_scan_ssids) || + nla_put_u8(msg, NL80211_ATTR_SCHED_SCAN_MAX_REQS, + rdev->wiphy.max_sched_scan_reqs) || nla_put_u8(msg, NL80211_ATTR_MAX_NUM_SCHED_SCAN_SSIDS, rdev->wiphy.max_sched_scan_ssids) || nla_put_u16(msg, NL80211_ATTR_MAX_SCAN_IE_LEN, @@ -7185,9 +7188,17 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, !rdev->ops->sched_scan_start) return -EOPNOTSUPP; - if (rdev->sched_scan_req) + /* + * allow only one legacy scheduled scan if user-space + * does not indicate multiple scheduled scan support. + */ + if (!info->attrs[NL80211_ATTR_SCHED_SCAN_MULTI] && + cfg80211_legacy_sched_scan_active(rdev)) return -EINPROGRESS; + if (rdev->sched_scan_req_count == rdev->wiphy.max_sched_scan_reqs) + return -ENOSPC; + sched_scan_req = nl80211_parse_sched_scan(&rdev->wiphy, wdev, info->attrs); @@ -7195,6 +7206,12 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, if (err) goto out_err; + /* leave request id zero for legacy request */ + if (info->attrs[NL80211_ATTR_SCHED_SCAN_MULTI]) { + while (!sched_scan_req->reqid) + sched_scan_req->reqid = rdev->wiphy.cookie_counter++; + } + err = rdev_sched_scan_start(rdev, dev, sched_scan_req); if (err) goto out_free; @@ -7205,7 +7222,7 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, if (info->attrs[NL80211_ATTR_SOCKET_OWNER]) sched_scan_req->owner_nlportid = info->snd_portid; - rcu_assign_pointer(rdev->sched_scan_req, sched_scan_req); + cfg80211_add_sched_scan_req(rdev, sched_scan_req); nl80211_send_sched_scan(rdev, dev, NL80211_CMD_START_SCHED_SCAN); @@ -7220,13 +7237,28 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, static int nl80211_stop_sched_scan(struct sk_buff *skb, struct genl_info *info) { + struct cfg80211_sched_scan_request *req; struct cfg80211_registered_device *rdev = info->user_ptr[0]; + u64 cookie; if (!(rdev->wiphy.flags & WIPHY_FLAG_SUPPORTS_SCHED_SCAN) || !rdev->ops->sched_scan_stop) return -EOPNOTSUPP; - return __cfg80211_stop_sched_scan(rdev, false); + if (info->attrs[NL80211_ATTR_COOKIE]) { + cookie = nla_get_u64(info->attrs[NL80211_ATTR_COOKIE]); + return __cfg80211_stop_sched_scan(rdev, cookie, false); + } else { + req = list_first_or_null_rcu(&rdev->sched_scan_req_list, + struct cfg80211_sched_scan_request, + list); + if (!req || req->reqid || + (req->owner_nlportid && + req->owner_nlportid != info->snd_portid)) + return -ENOENT; + + return cfg80211_stop_sched_scan_req(rdev, req, false); + } } static int nl80211_start_radar_detection(struct sk_buff *skb, diff --git a/net/wireless/scan.c b/net/wireless/scan.c index b5bd58d..942059e1 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -249,6 +249,46 @@ void cfg80211_scan_done(struct cfg80211_scan_request *request, } EXPORT_SYMBOL(cfg80211_scan_done); +void cfg80211_add_sched_scan_req(struct cfg80211_registered_device *rdev, + struct cfg80211_sched_scan_request *req) +{ + if (req->reqid) + list_add_tail_rcu(&req->list, &rdev->sched_scan_req_list); + else + list_add_rcu(&req->list, &rdev->sched_scan_req_list); + rdev->sched_scan_req_count++; +} + +static void cfg80211_del_sched_scan_req(struct cfg80211_registered_device *rdev, + struct cfg80211_sched_scan_request *req) +{ + list_del_rcu(&req->list); + kfree_rcu(req, rcu_head); + synchronize_rcu(); + rdev->sched_scan_req_count--; +} + +static struct cfg80211_sched_scan_request * +cfg80211_find_sched_scan_req(struct cfg80211_registered_device *rdev, u64 reqid) +{ + struct cfg80211_sched_scan_request *pos; + list_for_each_entry(pos, &rdev->sched_scan_req_list, list) { + if (pos->reqid == reqid) + return pos; + } + return ERR_PTR(-ENOENT); +} + +bool cfg80211_legacy_sched_scan_active(struct cfg80211_registered_device *rdev) +{ + struct cfg80211_sched_scan_request *req; + + req = list_first_or_null_rcu(&rdev->sched_scan_req_list, + struct cfg80211_sched_scan_request, list); + /* request id 0 indicates legacy request in progress */ + return req && !req->reqid; +} + void __cfg80211_sched_scan_results(struct work_struct *wk) { struct cfg80211_registered_device *rdev; @@ -295,7 +335,7 @@ void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy) trace_cfg80211_sched_scan_stopped(wiphy); - __cfg80211_stop_sched_scan(rdev, true); + __cfg80211_stop_sched_scan(rdev, 0, true); } EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl); @@ -307,34 +347,43 @@ void cfg80211_sched_scan_stopped(struct wiphy *wiphy) } EXPORT_SYMBOL(cfg80211_sched_scan_stopped); -int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, - bool driver_initiated) +int cfg80211_stop_sched_scan_req(struct cfg80211_registered_device *rdev, + struct cfg80211_sched_scan_request *req, + bool driver_initiated) { - struct cfg80211_sched_scan_request *sched_scan_req; - struct net_device *dev; - ASSERT_RTNL(); - if (!rdev->sched_scan_req) - return -ENOENT; - - sched_scan_req = rtnl_dereference(rdev->sched_scan_req); - dev = sched_scan_req->dev; - if (!driver_initiated) { - int err = rdev_sched_scan_stop(rdev, dev); + int err = rdev_sched_scan_stop(rdev, req->dev); if (err) return err; } - nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED); + nl80211_send_sched_scan(rdev, req->dev, NL80211_CMD_SCHED_SCAN_STOPPED); - RCU_INIT_POINTER(rdev->sched_scan_req, NULL); - kfree_rcu(sched_scan_req, rcu_head); + cfg80211_del_sched_scan_req(rdev, req); return 0; } +int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev, + u64 reqid, bool driver_initiated) +{ + struct cfg80211_sched_scan_request *sched_scan_req; + + ASSERT_RTNL(); + + if (!rdev->sched_scan_req_count) + return -ENOENT; + + sched_scan_req = cfg80211_find_sched_scan_req(rdev, reqid); + if (IS_ERR(sched_scan_req)) + return PTR_ERR(sched_scan_req); + + return cfg80211_stop_sched_scan_req(rdev, sched_scan_req, + driver_initiated); +} + void cfg80211_bss_age(struct cfg80211_registered_device *rdev, unsigned long age_secs) { @@ -1078,7 +1127,7 @@ struct cfg80211_bss * else rcu_assign_pointer(tmp.pub.beacon_ies, ies); rcu_assign_pointer(tmp.pub.ies, ies); - + memcpy(tmp.pub.bssid, mgmt->bssid, ETH_ALEN); tmp.pub.channel = channel; tmp.pub.scan_width = data->scan_width; -- 1.9.1
