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d80211: respect extra_tx_headroom

PATCH Applied Ivo van Doorn 3 participants 4 messages Feb 5, 2007 – Feb 8, 2007 1 message not in the archive

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Ivo van Doorn

author
#0 lore raw

PATCH 1/1 d80211: respect extra_tx_headroom

When a driver requested additional header room through the extra_tx_headroom field, the stack should respect that and make sure that all frames that are being send to the stack actually have that extra header room.

Signed-off-by Ivo van Doorn <[email protected]>

---

net/d80211/ieee80211.c +29 -6
diff -rU3 dscape/net/d80211/ieee80211.c dscape.hdr/net/d80211/ieee80211.c
@@ -472,10 +472,9 @@
 
 		/* reserve enough extra head and tail room for possible
 		 * encryption */
-#define IEEE80211_ENCRYPT_HEADROOM 8
-#define IEEE80211_ENCRYPT_TAILROOM 12
 		frag = frags[i] =
-			dev_alloc_skb(frag_threshold +
+			dev_alloc_skb(tx->local->hw.extra_tx_headroom +
+				      frag_threshold +
 				      IEEE80211_ENCRYPT_HEADROOM +
 				      IEEE80211_ENCRYPT_TAILROOM);
 		if (!frag)

@@ -483,7 +482,8 @@
 		/* Make sure that all fragments use the same priority so
 		 * that they end up using the same TX queue */
 		frag->priority = first->priority;
-		skb_reserve(frag, IEEE80211_ENCRYPT_HEADROOM);
+		skb_reserve(frag, tx->local->hw.extra_tx_headroom +
+			IEEE80211_ENCRYPT_HEADROOM);
 		fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen);
 		memcpy(fhdr, first->data, hdrlen);
 		if (i == num_fragm - 2)

@@ -858,10 +858,13 @@
 
 	hdr_len = ieee80211_get_hdrlen(old_hdr->frame_control);
 
-	tx->u.tx.rts_frame = dev_alloc_skb(hdr_len);
+	tx->u.tx.rts_frame = dev_alloc_skb(hdr_len +
+		tx->local->hw.extra_tx_headroom);
 	if (!tx->u.tx.rts_frame)
 		return TXRX_DROP;
 
+	skb_reserve(tx->u.tx.rts_frame, tx->local->hw.extra_tx_headroom);
+
 	new_hdr = (struct ieee80211_hdr*)skb_put(tx->u.tx.rts_frame, hdr_len);
 
 	memcpy(new_hdr, old_hdr, hdr_len);

@@ -1427,6 +1430,7 @@
 	struct ieee80211_tx_packet_data *pkt_data;
 	struct net_device *odev = NULL;
 	struct ieee80211_sub_if_data *osdata;
+	int headroom;
 	int ret;
 
 	/*

@@ -1451,6 +1455,15 @@
 	}
 	osdata = IEEE80211_DEV_TO_SUB_IF(odev);
 
+	headroom = osdata->local->hw.extra_tx_headroom +
+		IEEE80211_ENCRYPT_HEADROOM;
+	if (skb_headroom(skb) < headroom) {
+		if (pskb_expand_head(skb, headroom, 0, GFP_ATOMIC)) {
+			dev_kfree_skb(skb);
+			return 0;
+		}
+	}
+
 	control.ifindex = odev->ifindex;
 	control.type = osdata->type;
 	if (pkt_data->req_tx_status)

@@ -1680,6 +1693,14 @@
 		return 0;
 	}
 
+	if (skb_headroom(skb) < sdata->local->hw.extra_tx_headroom) {
+		if (pskb_expand_head(skb,
+		    sdata->local->hw.extra_tx_headroom, 0, GFP_ATOMIC)) {
+			dev_kfree_skb(skb);
+			return 0;
+		}
+	}
+
 	hdr = (struct ieee80211_hdr *) skb->data;
 	fc = le16_to_cpu(hdr->frame_control);
 

@@ -1813,10 +1834,12 @@
 	bh_len = ap->beacon_head_len;
 	bt_len = ap->beacon_tail_len;
 
-	skb = dev_alloc_skb(bh_len + bt_len + 256 /* maximum TIM len */);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+		bh_len + bt_len + 256 /* maximum TIM len */);
 	if (!skb)
 		return NULL;
 
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 	memcpy(skb_put(skb, bh_len), b_head, bh_len);
 
 	if (hw->flags & IEEE80211_HW_SOFTWARE_SEQUENCE)
net/d80211/ieee80211_i.h +3 -0
diff -rU3 dscape/net/d80211/ieee80211_i.h dscape.hdr/net/d80211/ieee80211_i.h
@@ -49,6 +49,9 @@
  * frame can be up to about 2 kB long. */
 #define TOTAL_MAX_TX_BUFFER 512
 
+/* Required encryption head and tailroom */
+#define IEEE80211_ENCRYPT_HEADROOM 8
+#define IEEE80211_ENCRYPT_TAILROOM 12
 
 /* IEEE 802.11 (Ch. 9.5 Defragmentation) requires support for concurrent
  * reception of at least three fragmented frames. This limit can be increased
net/d80211/ieee80211_scan.c +2 -1
diff -rU3 dscape/net/d80211/ieee80211_scan.c dscape.hdr/net/d80211/ieee80211_scan.c
@@ -280,7 +280,7 @@
 {
 	struct ieee80211_hdr hdr;
 	u16 fc;
-	int len = 10;
+	int len = 10 + local->hw.extra_tx_headroom;
 	struct rate_control_extra extra;
 
 	/* Only initialize passive scanning if the hardware supports it */

@@ -309,6 +309,7 @@
 		       "passive scan\n", local->mdev->name);
 		return;
 	}
+	skb_reserve(local->scan.skb, local->hw.extra_tx_headroom);
 
 	fc = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS;
 	hdr.frame_control = cpu_to_le16(fc);
net/d80211/ieee80211_sta.c +17 -5
diff -rU3 dscape/net/d80211/ieee80211_sta.c dscape.hdr/net/d80211/ieee80211_sta.c
@@ -415,15 +415,18 @@
 				int transaction, u8 *extra, size_t extra_len,
 				int encrypt)
 {
+	struct ieee80211_local *local = dev->ieee80211_ptr;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 
-	skb = dev_alloc_skb(sizeof(*mgmt) + 6 + extra_len);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    sizeof(*mgmt) + 6 + extra_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for auth "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24 + 6);
 	memset(mgmt, 0, 24 + 6);

@@ -478,13 +481,15 @@
 	struct ieee80211_sta_bss *bss;
 	int wmm = 0;
 
-	skb = dev_alloc_skb(sizeof(*mgmt) + 200 + ifsta->extra_ie_len +
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    sizeof(*mgmt) + 200 + ifsta->extra_ie_len +
 			    ifsta->ssid_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	capab = ifsta->capab;
 	if (local->hw.conf.phymode == MODE_IEEE80211G) {

@@ -585,15 +590,17 @@
 static void ieee80211_send_deauth(struct net_device *dev,
 				  struct ieee80211_if_sta *ifsta, u16 reason)
 {
+	struct ieee80211_local *local = dev->ieee80211_ptr;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 
-	skb = dev_alloc_skb(sizeof(*mgmt));
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt));
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for deauth "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 	memset(mgmt, 0, 24);

@@ -612,15 +619,17 @@
 static void ieee80211_send_disassoc(struct net_device *dev,
 				    struct ieee80211_if_sta *ifsta, u16 reason)
 {
+	struct ieee80211_local *local = dev->ieee80211_ptr;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 
-	skb = dev_alloc_skb(sizeof(*mgmt));
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt));
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for disassoc "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 	memset(mgmt, 0, 24);

@@ -758,12 +767,13 @@
 	u8 *pos, *supp_rates, *esupp_rates = NULL;
 	int i;
 
-	skb = dev_alloc_skb(sizeof(*mgmt) + 200);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) + 200);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
 		       "request\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 	memset(mgmt, 0, 24);

@@ -2007,6 +2017,8 @@
 		if (!skb)
 			break;
 
+		skb_reserve(skb, local->hw.extra_tx_headroom);
+
 		mgmt = (struct ieee80211_mgmt *)
 			skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 		memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
#1 lore raw
Quoted 10 lines · Ivo van Doorn

When a driver requested additional header room through the extra_tx_headroom field, the stack should respect that and make sure that all frames that are being send to the stack actually have that extra header room.

[...]
--- dscape/net/d80211/ieee80211_sta.c 2007-02-05 16:18:41.000000000 +0100
[...]

net/d80211/ieee80211_sta.c line 2024

Quoted 8 lines
net/d80211/ieee80211_sta.c +2 -0
@@ -2007,6 +2017,8 @@
 		if (!skb)
 			break;
 
+		skb_reserve(skb, local->hw.extra_tx_headroom);
+
 		mgmt = (struct ieee80211_mgmt *)
 			skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 		memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));

Please enlarge that dev_alloc_skb(400) few lines above by extra_tx_headroom as well.

Btw, it would be nice if you could use -p option for diff as it makes reviewing easier for me.

Thanks,

Jiri

Signature · 2 lines
Jiri Benc
SUSE Labs

A message that is not in the archive (sent off-list or not yet received): [email protected]

#3 lore raw
Quoted 14 lines · Jiri Benc
Quoted 13 lines · Ivo van Doorn

When a driver requested additional header room through the extra_tx_headroom field, the stack should respect that and make sure that all frames that are being send to the stack actually have that extra header room.

[...]
--- dscape/net/d80211/ieee80211_sta.c 2007-02-05 16:18:41.000000000 +0100
[...]

(quoted diff) +0 -0
@@ -2007,6 +2017,8 @@
 		if (!skb)
 			break;
Quoted 8 lines

Review line 2024

Quoted 5 lines
(quoted diff) +2 -0
+		skb_reserve(skb, local->hw.extra_tx_headroom);
+
 		mgmt = (struct ieee80211_mgmt *)
 			skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 		memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));

Please enlarge that dev_alloc_skb(400) few lines above by extra_tx_headroom as well.

Ok.

Quoted 2 lines

Btw, it would be nice if you could use -p option for diff as it makes reviewing easier for me.

Not a problem, I'll try to remember it for future patches.

Here is the updated patch.

When a driver requested additional header room
through the extra_tx_headroom field, the stack
should respect that and make sure that all frames
that are being send to the stack actually have
that extra header room.
Besides the additional bytes for the beacon template, this patch is no longer depends on the rts patch to be applied.

Signed-off-by Ivo van Doorn <[email protected]>

---

net/d80211/ieee80211.c +25 -5
diff -rpU3 dscape.control/net/d80211/ieee80211.c dscape.skb/net/d80211/ieee80211.c
@@ -470,10 +470,9 @@ ieee80211_tx_h_fragment(struct ieee80211
 
 		/* reserve enough extra head and tail room for possible
 		 * encryption */
-#define IEEE80211_ENCRYPT_HEADROOM 8
-#define IEEE80211_ENCRYPT_TAILROOM 12
 		frag = frags[i] =
-			dev_alloc_skb(frag_threshold +
+			dev_alloc_skb(tx->local->hw.extra_tx_headroom +
+				      frag_threshold +
 				      IEEE80211_ENCRYPT_HEADROOM +
 				      IEEE80211_ENCRYPT_TAILROOM);
 		if (!frag)

@@ -481,7 +480,8 @@ ieee80211_tx_h_fragment(struct ieee80211
 		/* Make sure that all fragments use the same priority so
 		 * that they end up using the same TX queue */
 		frag->priority = first->priority;
-		skb_reserve(frag, IEEE80211_ENCRYPT_HEADROOM);
+		skb_reserve(frag, tx->local->hw.extra_tx_headroom +
+			IEEE80211_ENCRYPT_HEADROOM);
 		fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen);
 		memcpy(fhdr, first->data, hdrlen);
 		if (i == num_fragm - 2)

@@ -1362,6 +1362,7 @@ static int ieee80211_master_start_xmit(s
 	struct ieee80211_tx_packet_data *pkt_data;
 	struct net_device *odev = NULL;
 	struct ieee80211_sub_if_data *osdata;
+	int headroom;
 	int ret;
 
 	/*

@@ -1386,6 +1387,15 @@ static int ieee80211_master_start_xmit(s
 	}
 	osdata = IEEE80211_DEV_TO_SUB_IF(odev);
 
+	headroom = osdata->local->hw.extra_tx_headroom +
+		IEEE80211_ENCRYPT_HEADROOM;
+	if (skb_headroom(skb) < headroom) {
+		if (pskb_expand_head(skb, headroom, 0, GFP_ATOMIC)) {
+			dev_kfree_skb(skb);
+			return 0;
+		}
+	}
+
 	control.ifindex = odev->ifindex;
 	control.type = osdata->type;
 	if (pkt_data->req_tx_status)

@@ -1615,6 +1625,14 @@ ieee80211_mgmt_start_xmit(struct sk_buff
 		return 0;
 	}
 
+	if (skb_headroom(skb) < sdata->local->hw.extra_tx_headroom) {
+		if (pskb_expand_head(skb,
+		    sdata->local->hw.extra_tx_headroom, 0, GFP_ATOMIC)) {
+			dev_kfree_skb(skb);
+			return 0;
+		}
+	}
+
 	hdr = (struct ieee80211_hdr *) skb->data;
 	fc = le16_to_cpu(hdr->frame_control);
 

@@ -1748,10 +1766,12 @@ struct sk_buff * ieee80211_beacon_get(st
 	bh_len = ap->beacon_head_len;
 	bt_len = ap->beacon_tail_len;
 
-	skb = dev_alloc_skb(bh_len + bt_len + 256 /* maximum TIM len */);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+		bh_len + bt_len + 256 /* maximum TIM len */);
 	if (!skb)
 		return NULL;
 
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 	memcpy(skb_put(skb, bh_len), b_head, bh_len);
 
 	ieee80211_beacon_add_tim(local, ap, skb);
net/d80211/ieee80211_i.h +3 -0
diff -rpU3 dscape.control/net/d80211/ieee80211_i.h dscape.skb/net/d80211/ieee80211_i.h
@@ -49,6 +49,9 @@ struct ieee80211_local;
  * frame can be up to about 2 kB long. */
 #define TOTAL_MAX_TX_BUFFER 512
 
+/* Required encryption head and tailroom */
+#define IEEE80211_ENCRYPT_HEADROOM 8
+#define IEEE80211_ENCRYPT_TAILROOM 12
 
 /* IEEE 802.11 (Ch. 9.5 Defragmentation) requires support for concurrent
  * reception of at least three fragmented frames. This limit can be increased
net/d80211/ieee80211_scan.c +2 -1
diff -rpU3 dscape.control/net/d80211/ieee80211_scan.c dscape.skb/net/d80211/ieee80211_scan.c
@@ -280,7 +280,7 @@ void ieee80211_init_scan(struct ieee8021
 {
 	struct ieee80211_hdr hdr;
 	u16 fc;
-	int len = 10;
+	int len = 10 + local->hw.extra_tx_headroom;
 	struct rate_control_extra extra;
 
 	/* Only initialize passive scanning if the hardware supports it */

@@ -309,6 +309,7 @@ void ieee80211_init_scan(struct ieee8021
 		       "passive scan\n", local->mdev->name);
 		return;
 	}
+	skb_reserve(local->scan.skb, local->hw.extra_tx_headroom);
 
 	fc = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS;
 	hdr.frame_control = cpu_to_le16(fc);
net/d80211/ieee80211_sta.c +18 -6
diff -rpU3 dscape.control/net/d80211/ieee80211_sta.c dscape.skb/net/d80211/ieee80211_sta.c
@@ -415,15 +415,18 @@ static void ieee80211_send_auth(struct n
 				int transaction, u8 *extra, size_t extra_len,
 				int encrypt)
 {
+	struct ieee80211_local *local = dev->ieee80211_ptr;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 
-	skb = dev_alloc_skb(sizeof(*mgmt) + 6 + extra_len);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    sizeof(*mgmt) + 6 + extra_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for auth "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24 + 6);
 	memset(mgmt, 0, 24 + 6);

@@ -478,13 +481,15 @@ static void ieee80211_send_assoc(struct 
 	struct ieee80211_sta_bss *bss;
 	int wmm = 0;
 
-	skb = dev_alloc_skb(sizeof(*mgmt) + 200 + ifsta->extra_ie_len +
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    sizeof(*mgmt) + 200 + ifsta->extra_ie_len +
 			    ifsta->ssid_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	capab = ifsta->capab;
 	if (local->hw.conf.phymode == MODE_IEEE80211G) {

@@ -585,15 +590,17 @@ static void ieee80211_send_assoc(struct 
 static void ieee80211_send_deauth(struct net_device *dev,
 				  struct ieee80211_if_sta *ifsta, u16 reason)
 {
+	struct ieee80211_local *local = dev->ieee80211_ptr;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 
-	skb = dev_alloc_skb(sizeof(*mgmt));
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt));
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for deauth "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 	memset(mgmt, 0, 24);

@@ -612,15 +619,17 @@ static void ieee80211_send_deauth(struct
 static void ieee80211_send_disassoc(struct net_device *dev,
 				    struct ieee80211_if_sta *ifsta, u16 reason)
 {
+	struct ieee80211_local *local = dev->ieee80211_ptr;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
 
-	skb = dev_alloc_skb(sizeof(*mgmt));
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt));
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for disassoc "
 		       "frame\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 	memset(mgmt, 0, 24);

@@ -758,12 +767,13 @@ static void ieee80211_send_probe_req(str
 	u8 *pos, *supp_rates, *esupp_rates = NULL;
 	int i;
 
-	skb = dev_alloc_skb(sizeof(*mgmt) + 200);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) + 200);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
 		       "request\n", dev->name);
 		return;
 	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 	memset(mgmt, 0, 24);

@@ -2002,11 +2012,13 @@ static int ieee80211_sta_join_ibss(struc
 	}
 
 	/* Set beacon template based on scan results */
-	skb = dev_alloc_skb(400);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
 	do {
 		if (!skb)
 			break;
 
+		skb_reserve(skb, local->hw.extra_tx_headroom);
+
 		mgmt = (struct ieee80211_mgmt *)
 			skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 		memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));

-
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Applied
#4 lore raw
Quoted 1 line · Ivo van Doorn

Not a problem, I'll try to remember it for future patches.

And please add a colon after Signed-off-by next time :-)

Quoted 1 line

Here is the updated patch.

Thanks, applied to my tree.

Jiri

Signature · 2 lines
Jiri Benc
SUSE Labs