--- 2.6.12.3.clean/include/linux/gfp.h	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/include/linux/gfp.h	2005-08-04 00:12:48.000000000 -0400
@@ -39,6 +39,7 @@
 #define __GFP_COMP	0x4000u	/* Add compound page metadata */
 #define __GFP_ZERO	0x8000u	/* Return zeroed page on success */
 #define __GFP_NOMEMALLOC 0x10000u /* Don't use emergency reserves */
+#define __GFP_MEMALLOC  0x20000u /* Use emergency reserves */
 
 #define __GFP_BITS_SHIFT 20	/* Room for 20 __GFP_FOO bits */
 #define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1)
--- 2.6.12.3.clean/include/linux/skbuff.h	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/include/linux/skbuff.h	2005-08-04 13:46:35.000000000 -0400
@@ -969,7 +969,6 @@
 		kfree_skb(skb);
 }
 
-#ifndef CONFIG_HAVE_ARCH_DEV_ALLOC_SKB
 /**
  *	__dev_alloc_skb - allocate an skbuff for sending
  *	@length: length to allocate
@@ -982,17 +981,17 @@
  *
  *	%NULL is returned in there is no free memory.
  */
-static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
-					      int gfp_mask)
+static inline struct sk_buff *__dev_alloc_skb(unsigned length, int gfp_mask)
 {
-	struct sk_buff *skb = alloc_skb(length + 16, gfp_mask);
+	int opaque = 16, size = length + opaque;
+	struct sk_buff *skb = alloc_skb(size, gfp_mask & ~__GFP_MEMALLOC);
+
+	if (unlikely(!skb) && (gfp_mask & __GFP_MEMALLOC))
+		skb = alloc_skb(size, gfp_mask);
 	if (likely(skb))
-		skb_reserve(skb, 16);
+		skb_reserve(skb, opaque);
 	return skb;
 }
-#else
-extern struct sk_buff *__dev_alloc_skb(unsigned int length, int gfp_mask);
-#endif
 
 /**
  *	dev_alloc_skb - allocate an skbuff for sending
@@ -1011,6 +1010,16 @@
 	return __dev_alloc_skb(length, GFP_ATOMIC);
 }
 
+static inline struct sk_buff *dev_alloc_skb_reserve(unsigned int length)
+{
+	return __dev_alloc_skb(length, gfp_mask | __GFP_MEMALLOC);
+}
+
+static inline int is_memalloc_skb(struct sk_buff *skb)
+{
+	return !!(skb->priority & __GFP_MEMALLOC);
+}
+
 /**
  *	skb_cow - copy header of skb when it is required
  *	@skb: buffer to cow
--- 2.6.12.3.clean/include/net/sock.h	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/include/net/sock.h	2005-08-04 00:12:49.000000000 -0400
@@ -382,6 +382,7 @@
 	SOCK_NO_LARGESEND, /* whether to sent large segments or not */
 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
+	SOCK_MEMALLOC, /* protocol can use memalloc reserve */
 };
 
 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
@@ -399,6 +400,11 @@
 	return test_bit(flag, &sk->sk_flags);
 }
 
+static inline int is_memalloc_sock(struct sock *sk)
+{
+	return sock_flag(sk, SOCK_MEMALLOC);
+}
+
 static inline void sk_acceptq_removed(struct sock *sk)
 {
 	sk->sk_ack_backlog--;
--- 2.6.12.3.clean/mm/page_alloc.c	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/mm/page_alloc.c	2005-08-04 00:12:49.000000000 -0400
@@ -802,8 +802,8 @@
 
 	/* This allocation should allow future memory freeing. */
 
-	if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE)))
-			&& !in_interrupt()) {
+	if ((((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE)))
+			&& !in_interrupt()) || (gfp_mask & __GFP_MEMALLOC)) {
 		if (!(gfp_mask & __GFP_NOMEMALLOC)) {
 			/* go through the zonelist yet again, ignoring mins */
 			for (i = 0; (z = zones[i]) != NULL; i++) {
--- 2.6.12.3.clean/net/core/dev.c	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/net/core/dev.c	2005-08-04 00:12:49.000000000 -0400
@@ -1452,6 +1452,11 @@
 	struct softnet_data *queue;
 	unsigned long flags;
 
+        if (unlikely(is_memalloc_skb(skb))) {
+                netif_receive_skb(skb);
+                return NET_RX_CN_HIGH;
+        }
+
 	/* if netpoll wants it, pretend we never saw it */
 	if (netpoll_rx(skb))
 		return NET_RX_DROP;
--- 2.6.12.3.clean/net/core/skbuff.c	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/net/core/skbuff.c	2005-08-04 00:12:49.000000000 -0400
@@ -355,7 +355,7 @@
 	n->nohdr = 0;
 	C(pkt_type);
 	C(ip_summed);
-	C(priority);
+	n->priority = skb->priority & ~__GFP_MEMALLOC;
 	C(protocol);
 	C(security);
 	n->destructor = NULL;
@@ -411,7 +411,7 @@
 	new->sk		= NULL;
 	new->dev	= old->dev;
 	new->real_dev	= old->real_dev;
-	new->priority	= old->priority;
+	new->priority	= old->priority & ~__GFP_MEMALLOC;
 	new->protocol	= old->protocol;
 	new->dst	= dst_clone(old->dst);
 #ifdef CONFIG_INET
--- 2.6.12.3.clean/net/ipv4/tcp_ipv4.c	2005-07-15 17:18:57.000000000 -0400
+++ 2.6.12.3/net/ipv4/tcp_ipv4.c	2005-08-04 00:12:49.000000000 -0400
@@ -1766,6 +1766,9 @@
 	if (!sk)
 		goto no_tcp_socket;
 
+	if (unlikely(is_memalloc_skb(skb)) && !is_memalloc_sock(sk))
+		goto discard_and_relse;
+
 process:
 	if (sk->sk_state == TCP_TIME_WAIT)
 		goto do_time_wait;