Commit abfd2374 authored by Malcolm Priestley's avatar Malcolm Priestley Committed by Greg Kroah-Hartman
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staging: vt6656: Use sk_buff buffer for tx header 



mac80211 can provide space for the driver to put a tx header on
the skb buffer instead coping the entire frame on to a local
buffer with the header.

To use this extra_tx_headroom must be set in mac80211 with the largest
possible header which is struct vnt_tx_buffer.

The driver has 8 possible combinations of tx header size which
are found in vnt_get_hdr_size replacing vnt_mac_hdr_pos.

Signed-off-by: default avatarMalcolm Priestley <tvboxspy@gmail.com>
Link: https://lore.kernel.org/r/7b967bfc-1d4b-4b45-efab-d54f16cca226@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 16438cf7

drivers/staging/vt6656/device.h

+1 −0
Original line number Diff line number Diff line
@@ -240,6 +240,7 @@ struct vnt_usb_send_context { 
	struct sk_buff *skb;

	struct urb *urb;

	struct ieee80211_hdr *hdr;

	void *tx_buffer;

	unsigned int buf_len;

	u32 frame_len;

	u16 tx_hdr_size;

drivers/staging/vt6656/main_usb.c

+1 −0
Original line number Diff line number Diff line
@@ -1053,6 +1053,7 @@ vt6656_probe(struct usb_interface *intf, const struct usb_device_id *id) 
	ieee80211_hw_set(priv->hw, SUPPORTS_PS);

	ieee80211_hw_set(priv->hw, PS_NULLFUNC_STACK);



	priv->hw->extra_tx_headroom = sizeof(struct vnt_tx_buffer);

	priv->hw->max_signal = 100;



	SET_IEEE80211_DEV(priv->hw, &intf->dev);

drivers/staging/vt6656/rxtx.c

+53 −38
Original line number Diff line number Diff line
@@ -188,19 +188,6 @@ static __le16 vnt_get_cts_duration(struct vnt_usb_send_context *context) 
					    context->frame_len, info);

}



static u16 vnt_mac_hdr_pos(struct vnt_usb_send_context *tx_context,

			   struct ieee80211_hdr *hdr)

{

	u8 *head = tx_context->data + offsetof(struct vnt_tx_buffer, fifo_head);

	u8 *hdr_pos = (u8 *)hdr;



	tx_context->hdr = hdr;

	if (!tx_context->hdr)

		return 0;



	return (u16)(hdr_pos - head);

}



static void vnt_rxtx_datahead_g(struct vnt_usb_send_context *tx_context,

				struct vnt_tx_datahead_g *buf)

{
@@ -221,8 +208,6 @@ static void vnt_rxtx_datahead_g(struct vnt_usb_send_context *tx_context, 
	buf->time_stamp_off_a = vnt_time_stamp_off(priv, rate);

	buf->time_stamp_off_b = vnt_time_stamp_off(priv,

						   priv->top_cck_basic_rate);



	tx_context->tx_hdr_size = vnt_mac_hdr_pos(tx_context, &buf->hdr);

}



static void vnt_rxtx_datahead_ab(struct vnt_usb_send_context *tx_context,
@@ -241,8 +226,6 @@ static void vnt_rxtx_datahead_ab(struct vnt_usb_send_context *tx_context, 
	/* Get Duration and TimeStampOff */

	buf->duration = hdr->duration_id;

	buf->time_stamp_off = vnt_time_stamp_off(priv, rate);



	tx_context->tx_hdr_size = vnt_mac_hdr_pos(tx_context, &buf->hdr);

}



static void vnt_fill_ieee80211_rts(struct vnt_usb_send_context *tx_context,
@@ -479,6 +462,39 @@ static void vnt_fill_txkey(struct vnt_usb_send_context *tx_context, 
	}

}



static u16 vnt_get_hdr_size(struct ieee80211_tx_info *info)

{

	u16 size = sizeof(struct vnt_tx_datahead_ab);



	if (info->control.use_cts_prot) {

		if (info->control.use_rts)

			size = sizeof(struct vnt_rts_g);

		else

			size = sizeof(struct vnt_cts);

	} else if (info->control.use_rts) {

		size = sizeof(struct vnt_rts_ab);

	}



	if (info->control.hw_key) {

		if (info->control.hw_key->cipher == WLAN_CIPHER_SUITE_CCMP)

			size += sizeof(struct vnt_mic_hdr);

	}



	/* Get rrv_time header */

	if (info->control.use_cts_prot) {

		if (info->control.use_rts)

			size += sizeof(struct vnt_rrv_time_rts);

		else

			size += sizeof(struct vnt_rrv_time_cts);

	} else {

		size += sizeof(struct vnt_rrv_time_ab);

	}



	size += sizeof(struct vnt_tx_fifo_head);



	return size;

}



int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb)

{

	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
@@ -531,12 +547,29 @@ int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb) 
	tx_context->need_ack = false;

	tx_context->frame_len = skb->len + 4;

	tx_context->tx_rate =  rate->hw_value;

	tx_context->hdr = hdr;



	spin_unlock_irqrestore(&priv->lock, flags);



	tx_buffer = (struct vnt_tx_buffer *)tx_context->data;

	tx_buffer_head = &tx_buffer->fifo_head;

	tx_header_size = vnt_get_hdr_size(info);

	tx_body_size = skb->len;

	tx_bytes = tx_header_size + tx_body_size;

	tx_header_size += sizeof(struct vnt_tx_usb_header);



	tx_buffer = skb_push(skb, tx_header_size);

	tx_buffer_head = &tx_buffer->fifo_head;



	/* Fill USB header */

	tx_buffer->usb.tx_byte_count = cpu_to_le16(tx_bytes);

	tx_buffer->usb.pkt_no = tx_context->pkt_no;

	tx_buffer->usb.type = 0x00;



	tx_context->type = CONTEXT_DATA_PACKET;

	tx_context->tx_buffer = tx_buffer;

	tx_context->buf_len = skb->len;



	/* Return skb->data to mac80211 header */

	skb_pull(skb, tx_header_size);



	/*Set fifo controls */

	if (pkt_type == PK_TYPE_11A)
@@ -603,18 +636,8 @@ int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb) 
	vnt_generate_tx_parameter(tx_context, tx_buffer, &mic_hdr,

				  need_mic, need_rts);



	tx_header_size = tx_context->tx_hdr_size;

	if (!tx_header_size) {

		tx_context->in_use = false;

		return -ENOMEM;

	}



	tx_buffer_head->frag_ctl |= cpu_to_le16(FRAGCTL_NONFRAG);



	tx_bytes = tx_header_size + tx_body_size;



	memcpy(tx_context->hdr, skb->data, tx_body_size);



	if (info->control.hw_key) {

		tx_key = info->control.hw_key;

		if (tx_key->keylen > 0)
@@ -625,15 +648,6 @@ int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb) 
	priv->seq_counter = (le16_to_cpu(hdr->seq_ctrl) &

						IEEE80211_SCTL_SEQ) >> 4;



	tx_buffer->tx_byte_count = cpu_to_le16(tx_bytes);

	tx_buffer->pkt_no = tx_context->pkt_no;

	tx_buffer->type = 0x00;



	tx_bytes += 4;



	tx_context->type = CONTEXT_DATA_PACKET;

	tx_context->buf_len = tx_bytes;



	spin_lock_irqsave(&priv->lock, flags);



	if (vnt_tx_context(priv, tx_context)) {
@@ -725,6 +739,7 @@ static int vnt_beacon_xmit(struct vnt_private *priv, struct sk_buff *skb) 
	beacon_buffer->type = 0x01;



	context->type = CONTEXT_BEACON_PACKET;

	context->tx_buffer = &context->data;

	context->buf_len = count + 4; /* USB header */



	spin_lock_irqsave(&priv->lock, flags);

drivers/staging/vt6656/rxtx.h

+5 −3
Original line number Diff line number Diff line
@@ -77,14 +77,12 @@ struct vnt_tx_datahead_g { 
	__le16 duration_a;

	__le16 time_stamp_off_b;

	__le16 time_stamp_off_a;

	struct ieee80211_hdr hdr;

} __packed;



struct vnt_tx_datahead_ab {

	struct vnt_phy_field ab;

	__le16 duration;

	__le16 time_stamp_off;

	struct ieee80211_hdr hdr;

} __packed;



/* RTS buffer header */
@@ -161,10 +159,14 @@ struct vnt_tx_fifo_head { 
	__le16 current_rate;

} __packed;



struct vnt_tx_buffer {

struct vnt_tx_usb_header {

	u8 type;

	u8 pkt_no;

	__le16 tx_byte_count;

} __packed;



struct vnt_tx_buffer {

	struct vnt_tx_usb_header usb;

	struct vnt_tx_fifo_head fifo_head;

	union vnt_tx_head tx_head;

} __packed;

drivers/staging/vt6656/usbpipe.c

+1 −1
Original line number Diff line number Diff line
@@ -466,7 +466,7 @@ int vnt_tx_context(struct vnt_private *priv, 
	usb_fill_bulk_urb(urb,

			  priv->usb,

			  usb_sndbulkpipe(priv->usb, 3),

			  context->data,

			  context->tx_buffer,

			  context->buf_len,

			  vnt_tx_context_complete,

			  context);