blob: 487193f1de1a6b0ac70e04dcfd0575a0ac091bb8 [file] [log] [blame]
Christian Lampartera1c55582009-04-14 22:11:20 +02001/*
2 * Copyright (c) 2009 Atheros Communications Inc.
3 *
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#include <linux/kernel.h>
18#include <linux/module.h>
19
Luis R. Rodriguezd15dd3e2009-08-12 09:56:59 -070020#include "ath.h"
21
Christian Lampartera1c55582009-04-14 22:11:20 +020022MODULE_AUTHOR("Atheros Communications");
23MODULE_DESCRIPTION("Shared library for Atheros wireless LAN cards.");
24MODULE_LICENSE("Dual BSD/GPL");
Luis R. Rodriguezd15dd3e2009-08-12 09:56:59 -070025
26struct sk_buff *ath_rxbuf_alloc(struct ath_common *common,
27 u32 len,
28 gfp_t gfp_mask)
29{
30 struct sk_buff *skb;
31 u32 off;
32
33 /*
34 * Cache-line-align. This is important (for the
35 * 5210 at least) as not doing so causes bogus data
36 * in rx'd frames.
37 */
38
39 /* Note: the kernel can allocate a value greater than
40 * what we ask it to give us. We really only need 4 KB as that
41 * is this hardware supports and in fact we need at least 3849
42 * as that is the MAX AMSDU size this hardware supports.
43 * Unfortunately this means we may get 8 KB here from the
44 * kernel... and that is actually what is observed on some
45 * systems :( */
46 skb = __dev_alloc_skb(len + common->cachelsz - 1, gfp_mask);
47 if (skb != NULL) {
48 off = ((unsigned long) skb->data) % common->cachelsz;
49 if (off != 0)
50 skb_reserve(skb, common->cachelsz - off);
51 } else {
52 printk(KERN_ERR "skbuff alloc of size %u failed\n", len);
53 return NULL;
54 }
55
56 return skb;
57}
58EXPORT_SYMBOL(ath_rxbuf_alloc);