1 files changed, 36 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/main.c b/drivers/net/wireless/ath/main.c
index 9949b11cb151..487193f1de1a 100644
--- a/drivers/net/wireless/ath/main.c
+++ b/drivers/net/wireless/ath/main.c
@@ -17,6 +17,42 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 
+#include "ath.h"
+
 MODULE_AUTHOR("Atheros Communications");
 MODULE_DESCRIPTION("Shared library for Atheros wireless LAN cards.");
 MODULE_LICENSE("Dual BSD/GPL");
+
+struct sk_buff *ath_rxbuf_alloc(struct ath_common *common,
+                                u32 len,
+                                gfp_t gfp_mask)
+{
+        struct sk_buff *skb;
+        u32 off;
+
+        /*
+         * Cache-line-align.  This is important (for the
+         * 5210 at least) as not doing so causes bogus data
+         * in rx'd frames.
+         */
+
+        /* Note: the kernel can allocate a value greater than
+         * what we ask it to give us. We really only need 4 KB as that
+         * is this hardware supports and in fact we need at least 3849
+         * as that is the MAX AMSDU size this hardware supports.
+         * Unfortunately this means we may get 8 KB here from the
+         * kernel... and that is actually what is observed on some
+         * systems :( */
+        skb = __dev_alloc_skb(len + common->cachelsz - 1, gfp_mask);
+        if (skb != NULL) {
+                off = ((unsigned long) skb->data) % common->cachelsz;
+                if (off != 0)
+                        skb_reserve(skb, common->cachelsz - off);
+        } else {
+                printk(KERN_ERR "skbuff alloc of size %u failed\n", len);
+                return NULL;
+        }
+
+        return skb;
+}
+EXPORT_SYMBOL(ath_rxbuf_alloc);