Commit bb4793b3 authored by David Gnedt's avatar David Gnedt Committed by John W. Linville
Browse files

wl1251: fix 4-byte TX buffer alignment 



This implements TX buffer alignment for cloned or too small skb by
copying and replacing the original skb.
Recent changes in wireless-testing seems to make this really necessary.

Signed-off-by: default avatarDavid Gnedt <david.gnedt@davizone.at>
Acked-by: default avatarKalle Valo <kvalo@adurom.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent e7332a41

drivers/net/wireless/wl1251/tx.c

+20 −6
Original line number Diff line number Diff line
@@ -213,16 +213,30 @@ static int wl1251_tx_send_packet(struct wl1251 *wl, struct sk_buff *skb, 
		wl1251_debug(DEBUG_TX, "skb offset %d", offset);



		/* check whether the current skb can be used */

		if (!skb_cloned(skb) && (skb_tailroom(skb) >= offset)) {

			unsigned char *src = skb->data;

		if (skb_cloned(skb) || (skb_tailroom(skb) < offset)) {

			struct sk_buff *newskb = skb_copy_expand(skb, 0, 3,

								 GFP_KERNEL);



			if (unlikely(newskb == NULL)) {

				wl1251_error("Can't allocate skb!");

				return -EINVAL;

			}



			tx_hdr = (struct tx_double_buffer_desc *) newskb->data;



			dev_kfree_skb_any(skb);

			wl->tx_frames[tx_hdr->id] = skb = newskb;



			offset = (4 - (long)skb->data) & 0x03;

			wl1251_debug(DEBUG_TX, "new skb offset %d", offset);

		}



		/* align the buffer on a 4-byte boundary */

		if (offset) {

			unsigned char *src = skb->data;

			skb_reserve(skb, offset);

			memmove(skb->data, src, skb->len);

			tx_hdr = (struct tx_double_buffer_desc *) skb->data;

		} else {

			wl1251_info("No handler, fixme!");

			return -EINVAL;

		}

	}