This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / xen / core / skbuff.c

diff --git a/drivers/xen/core/skbuff.c b/drivers/xen/core/skbuff.c
new file mode 100644 (file)
index 0000000..f38f3cf
--- /dev/null
+++ b/drivers/xen/core/skbuff.c
@@ -0,0 +1,141 @@
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <asm/io.h>
+#include <asm/page.h>
+#include <asm/hypervisor.h>
+
+/* Referenced in netback.c. */
+/*static*/ kmem_cache_t *skbuff_cachep;
+EXPORT_SYMBOL(skbuff_cachep);
+
+#define MAX_SKBUFF_ORDER 4
+static kmem_cache_t *skbuff_order_cachep[MAX_SKBUFF_ORDER + 1];
+
+static struct {
+       int size;
+       kmem_cache_t *cachep;
+} skbuff_small[] = { { 512, NULL }, { 2048, NULL } };
+
+struct sk_buff *__alloc_skb(unsigned int length, gfp_t gfp_mask,
+                           int fclone)
+{
+       int order, i;
+       kmem_cache_t *cachep;
+
+       length = SKB_DATA_ALIGN(length) + sizeof(struct skb_shared_info);
+
+       if (length <= skbuff_small[ARRAY_SIZE(skbuff_small)-1].size) {
+               for (i = 0; skbuff_small[i].size < length; i++)
+                       continue;
+               cachep = skbuff_small[i].cachep;
+       } else {
+               order = get_order(length);
+               if (order > MAX_SKBUFF_ORDER) {
+                       printk(KERN_ALERT "Attempt to allocate order %d "
+                              "skbuff. Increase MAX_SKBUFF_ORDER.\n", order);
+                       return NULL;
+               }
+               cachep = skbuff_order_cachep[order];
+       }
+
+       length -= sizeof(struct skb_shared_info);
+
+       return alloc_skb_from_cache(cachep, length, gfp_mask, fclone);
+}
+
+struct sk_buff *__dev_alloc_skb(unsigned int length, gfp_t gfp_mask)
+{
+       struct sk_buff *skb;
+       int order;
+
+       length = SKB_DATA_ALIGN(length + 16);
+       order = get_order(length + sizeof(struct skb_shared_info));
+       if (order > MAX_SKBUFF_ORDER) {
+               printk(KERN_ALERT "Attempt to allocate order %d skbuff. "
+                      "Increase MAX_SKBUFF_ORDER.\n", order);
+               return NULL;
+       }
+
+       skb = alloc_skb_from_cache(
+               skbuff_order_cachep[order], length, gfp_mask, 0);
+       if (skb != NULL)
+               skb_reserve(skb, 16);
+
+       return skb;
+}
+
+static void skbuff_ctor(void *buf, kmem_cache_t *cachep, unsigned long unused)
+{
+       int order = 0;
+
+       while (skbuff_order_cachep[order] != cachep)
+               order++;
+
+       /* Do our best to allocate contiguous memory but fall back to IOMMU. */
+       if (order != 0)
+               (void)xen_create_contiguous_region(
+                       (unsigned long)buf, order, 0);
+
+       scrub_pages(buf, 1 << order);
+}
+
+static void skbuff_dtor(void *buf, kmem_cache_t *cachep, unsigned long unused)
+{
+       int order = 0;
+
+       while (skbuff_order_cachep[order] != cachep)
+               order++;
+
+       if (order != 0)
+               xen_destroy_contiguous_region((unsigned long)buf, order);
+}
+
+static int __init skbuff_init(void)
+{
+       static char name[MAX_SKBUFF_ORDER + 1][20];
+       static char small_name[ARRAY_SIZE(skbuff_small)][20];
+       unsigned long size;
+       int i, order;
+
+       for (i = 0; i < ARRAY_SIZE(skbuff_small); i++) {
+               size = skbuff_small[i].size;
+               sprintf(small_name[i], "xen-skb-%lu", size);
+               /*
+                * No ctor/dtor: objects do not span page boundaries, and they
+                * are only used on transmit path so no need for scrubbing.
+                */
+               skbuff_small[i].cachep = kmem_cache_create(
+                       small_name[i], size, size, 0, NULL, NULL);
+       }
+
+       for (order = 0; order <= MAX_SKBUFF_ORDER; order++) {
+               size = PAGE_SIZE << order;
+               sprintf(name[order], "xen-skb-%lu", size);
+               if (is_running_on_xen() &&
+                   (xen_start_info->flags & SIF_PRIVILEGED))
+                       skbuff_order_cachep[order] = kmem_cache_create(
+                               name[order], size, size, 0,
+                               skbuff_ctor, skbuff_dtor);
+               else
+                       skbuff_order_cachep[order] = kmem_cache_create(
+                               name[order], size, size, 0, NULL, NULL);
+                       
+       }
+
+       skbuff_cachep = skbuff_order_cachep[0];
+
+       return 0;
+}
+core_initcall(skbuff_init);
+
+EXPORT_SYMBOL(__dev_alloc_skb);