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 <dimitrysh@xxxxxxxxxx>
Signed-off-by: Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx>
---
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
