mac80211: support more than one band in scan request

Some drivers (such as iwlmvm) can handle multiple bands in a single
HW scan request. Add a HW flag to indicate that the driver support
this. To hold the required data, create a separate structure for
HW scan request that holds cfg scan request and data about
different parts of the scan IEs.

As this changes the mac80211 API, update all drivers using it to
use the correct new function type/argument.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

4 files changed, 140 insertions, 61 deletions

diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 2265bd7..faa0d90 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -314,7 +314,7 @@ static inline void drv_update_tkip_key(struct ieee80211_local *local,
 
 static inline int drv_hw_scan(struct ieee80211_local *local,
 			      struct ieee80211_sub_if_data *sdata,
-			      struct cfg80211_scan_request *req)
+			      struct ieee80211_scan_request *req)
 {
 	int ret;
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 6c80894..f88bd16 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1152,7 +1152,8 @@ struct ieee80211_local {
 	unsigned long scanning;
 	struct cfg80211_ssid scan_ssid;
 	struct cfg80211_scan_request *int_scan_req;
-	struct cfg80211_scan_request *scan_req, *hw_scan_req;
+	struct cfg80211_scan_request *scan_req;
+	struct ieee80211_scan_request *hw_scan_req;
 	struct cfg80211_chan_def scan_chandef;
 	enum ieee80211_band hw_scan_band;
 	int scan_channel_idx;
@@ -1756,8 +1757,10 @@ void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata,
 				    const u8 *bssid, u16 stype, u16 reason,
 				    bool send_frame, u8 *frame_buf);
 int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
-			     size_t buffer_len, const u8 *ie, size_t ie_len,
-			     enum ieee80211_band band, u32 rate_mask,
+			     size_t buffer_len,
+			     struct ieee80211_scan_ies *ie_desc,
+			     const u8 *ie, size_t ie_len,
+			     u8 bands_used, u32 *rate_masks,
 			     struct cfg80211_chan_def *chandef);
 struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 					  u8 *dst, u32 ratemask,
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index f40661e..116959e 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -235,38 +235,51 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
 {
 	struct cfg80211_scan_request *req = local->scan_req;
 	struct cfg80211_chan_def chandef;
-	enum ieee80211_band band;
+	u8 bands_used = 0;
 	int i, ielen, n_chans;
 
 	if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
 		return false;
 
-	do {
-		if (local->hw_scan_band == IEEE80211_NUM_BANDS)
-			return false;
-
-		band = local->hw_scan_band;
-		n_chans = 0;
+	if (local->hw.flags & IEEE80211_SINGLE_HW_SCAN_ON_ALL_BANDS) {
 		for (i = 0; i < req->n_channels; i++) {
-			if (req->channels[i]->band == band) {
-				local->hw_scan_req->channels[n_chans] =
+			local->hw_scan_req->req.channels[i] = req->channels[i];
+			bands_used |= BIT(req->channels[i]->band);
+		}
+
+		n_chans = req->n_channels;
+	} else {
+		do {
+			if (local->hw_scan_band == IEEE80211_NUM_BANDS)
+				return false;
+
+			n_chans = 0;
+
+			for (i = 0; i < req->n_channels; i++) {
+				if (req->channels[i]->band !=
+				    local->hw_scan_band)
+					continue;
+				local->hw_scan_req->req.channels[n_chans] =
 							req->channels[i];
 				n_chans++;
+				bands_used |= BIT(req->channels[i]->band);
 			}
-		}
 
-		local->hw_scan_band++;
-	} while (!n_chans);
+			local->hw_scan_band++;
+		} while (!n_chans);
+	}
 
-	local->hw_scan_req->n_channels = n_chans;
+	local->hw_scan_req->req.n_channels = n_chans;
 	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
 
-	ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie,
+	ielen = ieee80211_build_preq_ies(local,
+					 (u8 *)local->hw_scan_req->req.ie,
 					 local->hw_scan_ies_bufsize,
-					 req->ie, req->ie_len, band,
-					 req->rates[band], &chandef);
-	local->hw_scan_req->ie_len = ielen;
-	local->hw_scan_req->no_cck = req->no_cck;
+					 &local->hw_scan_req->ies,
+					 req->ie, req->ie_len,
+					 bands_used, req->rates, &chandef);
+	local->hw_scan_req->req.ie_len = ielen;
+	local->hw_scan_req->req.no_cck = req->no_cck;
 
 	return true;
 }
@@ -291,7 +304,9 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 	if (WARN_ON(!local->scan_req))
 		return;
 
-	if (hw_scan && !aborted && ieee80211_prep_hw_scan(local)) {
+	if (hw_scan && !aborted &&
+	    !(local->hw.flags & IEEE80211_SINGLE_HW_SCAN_ON_ALL_BANDS) &&
+	    ieee80211_prep_hw_scan(local)) {
 		int rc;
 
 		rc = drv_hw_scan(local,
@@ -473,6 +488,21 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 		u8 *ies;
 
 		local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
+
+		if (local->hw.flags & IEEE80211_SINGLE_HW_SCAN_ON_ALL_BANDS) {
+			int i, n_bands = 0;
+			u8 bands_counted = 0;
+
+			for (i = 0; i < req->n_channels; i++) {
+				if (bands_counted & BIT(req->channels[i]->band))
+					continue;
+				bands_counted |= BIT(req->channels[i]->band);
+				n_bands++;
+			}
+
+			local->hw_scan_ies_bufsize *= n_bands;
+		}
+
 		local->hw_scan_req = kmalloc(
 				sizeof(*local->hw_scan_req) +
 				req->n_channels * sizeof(req->channels[0]) +
@@ -480,13 +510,13 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
 		if (!local->hw_scan_req)
 			return -ENOMEM;
 
-		local->hw_scan_req->ssids = req->ssids;
-		local->hw_scan_req->n_ssids = req->n_ssids;
+		local->hw_scan_req->req.ssids = req->ssids;
+		local->hw_scan_req->req.n_ssids = req->n_ssids;
 		ies = (u8 *)local->hw_scan_req +
 			sizeof(*local->hw_scan_req) +
 			req->n_channels * sizeof(req->channels[0]);
-		local->hw_scan_req->ie = ies;
-		local->hw_scan_req->flags = req->flags;
+		local->hw_scan_req->req.ie = ies;
+		local->hw_scan_req->req.flags = req->flags;
 
 		local->hw_scan_band = 0;
 
@@ -976,6 +1006,7 @@ int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_sched_scan_ies sched_scan_ies = {};
 	struct cfg80211_chan_def chandef;
 	int ret, i, iebufsz;
+	struct ieee80211_scan_ies dummy_ie_desc;
 
 	iebufsz = local->scan_ies_len + req->ie_len;
 
@@ -985,6 +1016,8 @@ int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
 		return -ENOTSUPP;
 
 	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+		u32 rate_masks[IEEE80211_NUM_BANDS] = {};
+
 		if (!local->hw.wiphy->bands[i])
 			continue;
 
@@ -995,11 +1028,13 @@ int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
 		}
 
 		ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
+		rate_masks[i] = (u32) -1;
 
 		sched_scan_ies.len[i] =
 			ieee80211_build_preq_ies(local, sched_scan_ies.ie[i],
-						 iebufsz, req->ie, req->ie_len,
-						 i, (u32) -1, &chandef);
+						 iebufsz, &dummy_ie_desc,
+						 req->ie, req->ie_len, BIT(i),
+						 rate_masks, &chandef);
 	}
 
 	ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 42d448d..e314582 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1219,14 +1219,17 @@ void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata,
 	}
 }
 
-int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
-			     size_t buffer_len, const u8 *ie, size_t ie_len,
-			     enum ieee80211_band band, u32 rate_mask,
-			     struct cfg80211_chan_def *chandef)
+static int ieee80211_build_preq_ies_band(struct ieee80211_local *local,
+					 u8 *buffer, size_t buffer_len,
+					 const u8 *ie, size_t ie_len,
+					 enum ieee80211_band band,
+					 u32 rate_mask,
+					 struct cfg80211_chan_def *chandef,
+					 size_t *offset)
 {
 	struct ieee80211_supported_band *sband;
 	u8 *pos = buffer, *end = buffer + buffer_len;
-	size_t offset = 0, noffset;
+	size_t noffset;
 	int supp_rates_len, i;
 	u8 rates[32];
 	int num_rates;
@@ -1234,6 +1237,8 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 	int shift;
 	u32 rate_flags;
 
+	*offset = 0;
+
 	sband = local->hw.wiphy->bands[band];
 	if (WARN_ON_ONCE(!sband))
 		return 0;
@@ -1272,12 +1277,12 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 		noffset = ieee80211_ie_split(ie, ie_len,
 					     before_extrates,
 					     ARRAY_SIZE(before_extrates),
-					     offset);
-		if (end - pos < noffset - offset)
+					     *offset);
+		if (end - pos < noffset - *offset)
 			goto out_err;
-		memcpy(pos, ie + offset, noffset - offset);
-		pos += noffset - offset;
-		offset = noffset;
+		memcpy(pos, ie + *offset, noffset - *offset);
+		pos += noffset - *offset;
+		*offset = noffset;
 	}
 
 	ext_rates_len = num_rates - supp_rates_len;
@@ -1311,12 +1316,12 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 		};
 		noffset = ieee80211_ie_split(ie, ie_len,
 					     before_ht, ARRAY_SIZE(before_ht),
-					     offset);
-		if (end - pos < noffset - offset)
+					     *offset);
+		if (end - pos < noffset - *offset)
 			goto out_err;
-		memcpy(pos, ie + offset, noffset - offset);
-		pos += noffset - offset;
-		offset = noffset;
+		memcpy(pos, ie + *offset, noffset - *offset);
+		pos += noffset - *offset;
+		*offset = noffset;
 	}
 
 	if (sband->ht_cap.ht_supported) {
@@ -1351,12 +1356,12 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 		};
 		noffset = ieee80211_ie_split(ie, ie_len,
 					     before_vht, ARRAY_SIZE(before_vht),
-					     offset);
-		if (end - pos < noffset - offset)
+					     *offset);
+		if (end - pos < noffset - *offset)
 			goto out_err;
-		memcpy(pos, ie + offset, noffset - offset);
-		pos += noffset - offset;
-		offset = noffset;
+		memcpy(pos, ie + *offset, noffset - *offset);
+		pos += noffset - *offset;
+		*offset = noffset;
 	}
 
 	if (sband->vht_cap.vht_supported) {
@@ -1366,21 +1371,54 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
 						 sband->vht_cap.cap);
 	}
 
-	/* add any remaining custom IEs */
-	if (ie && ie_len) {
-		noffset = ie_len;
-		if (end - pos < noffset - offset)
-			goto out_err;
-		memcpy(pos, ie + offset, noffset - offset);
-		pos += noffset - offset;
-	}
-
 	return pos - buffer;
  out_err:
 	WARN_ONCE(1, "not enough space for preq IEs\n");
 	return pos - buffer;
 }
 
+int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
+			     size_t buffer_len,
+			     struct ieee80211_scan_ies *ie_desc,
+			     const u8 *ie, size_t ie_len,
+			     u8 bands_used, u32 *rate_masks,
+			     struct cfg80211_chan_def *chandef)
+{
+	size_t pos = 0, old_pos = 0, custom_ie_offset = 0;
+	int i;
+
+	memset(ie_desc, 0, sizeof(*ie_desc));
+
+	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+		if (bands_used & BIT(i)) {
+			pos += ieee80211_build_preq_ies_band(local,
+							     buffer + pos,
+							     buffer_len - pos,
+							     ie, ie_len, i,
+							     rate_masks[i],
+							     chandef,
+							     &custom_ie_offset);
+			ie_desc->ies[i] = buffer + old_pos;
+			ie_desc->len[i] = pos - old_pos;
+			old_pos = pos;
+		}
+	}
+
+	/* add any remaining custom IEs */
+	if (ie && ie_len) {
+		if (WARN_ONCE(buffer_len - pos < ie_len - custom_ie_offset,
+			      "not enough space for preq custom IEs\n"))
+			return pos;
+		memcpy(buffer + pos, ie + custom_ie_offset,
+		       ie_len - custom_ie_offset);
+		ie_desc->common_ies = buffer + pos;
+		ie_desc->common_ie_len = ie_len - custom_ie_offset;
+		pos += ie_len - custom_ie_offset;
+	}
+
+	return pos;
+};
+
 struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 					  u8 *dst, u32 ratemask,
 					  struct ieee80211_channel *chan,
@@ -1393,6 +1431,8 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 	int ies_len;
+	u32 rate_masks[IEEE80211_NUM_BANDS] = {};
+	struct ieee80211_scan_ies dummy_ie_desc;
 
 	/*
 	 * Do not send DS Channel parameter for directed probe requests
@@ -1410,10 +1450,11 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
 	if (!skb)
 		return NULL;
 
+	rate_masks[chan->band] = ratemask;
 	ies_len = ieee80211_build_preq_ies(local, skb_tail_pointer(skb),
-					   skb_tailroom(skb),
-					   ie, ie_len, chan->band,
-					   ratemask, &chandef);
+					   skb_tailroom(skb), &dummy_ie_desc,
+					   ie, ie_len, BIT(chan->band),
+					   rate_masks, &chandef);
 	skb_put(skb, ies_len);
 
 	if (dst) {