---
 include/linux/swap.h |    2 ++
 mm/page_alloc.c      |   11 +++++++++++
 mm/vmscan.c          |   27 +++++++++++++++++++++++++++
 3 files changed, 40 insertions(+)

Index: linux-2.6/include/linux/swap.h
===================================================================
--- linux-2.6.orig/include/linux/swap.h	2007-08-08 04:31:06.000000000 -0700
+++ linux-2.6/include/linux/swap.h	2007-08-08 04:31:28.000000000 -0700
@@ -190,6 +190,8 @@ extern void swap_setup(void);
 /* linux/mm/vmscan.c */
 extern unsigned long try_to_free_pages(struct zone **zones, int order,
 					gfp_t gfp_mask);
+extern unsigned long emergency_free_pages(struct zone **zones, int order,
+					gfp_t gfp_mask);
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
Index: linux-2.6/mm/page_alloc.c
===================================================================
--- linux-2.6.orig/mm/page_alloc.c	2007-08-08 04:17:33.000000000 -0700
+++ linux-2.6/mm/page_alloc.c	2007-08-08 04:39:26.000000000 -0700
@@ -1306,6 +1306,17 @@ nofail_alloc:
 				zonelist, ALLOC_NO_WATERMARKS);
 			if (page)
 				goto got_pg;
+
+			/*
+			 * We cannot go into full synchrononous reclaim
+			 * but we can still scan for easily reclaimable
+			 * pages.
+			 */
+			if (p->flags & PF_MEMALLOC &&
+				emergency_free_pages(zonelist->zones, order,
+								gfp_mask))
+				goto nofail_alloc;
+
 			if (gfp_mask & __GFP_NOFAIL) {
 				congestion_wait(WRITE, HZ/50);
 				goto nofail_alloc;
Index: linux-2.6/mm/vmscan.c
===================================================================
--- linux-2.6.orig/mm/vmscan.c	2007-08-08 04:21:14.000000000 -0700
+++ linux-2.6/mm/vmscan.c	2007-08-08 04:42:24.000000000 -0700
@@ -1204,6 +1204,33 @@ out:
 }
 
 /*
+ * Emergency reclaim. We are alreedy in the vm write out path
+ * and we have exhausted all memory. We have to free memory without
+ * any additional allocations. So no writes and no swap. Get
+ * as bare bones as we can.
+ */
+unsigned long emergency_free_pages(struct zone **zones, int order, gfp_t gfp_mask)
+{
+	int priority;
+	unsigned long nr_reclaimed = 0;
+	struct scan_control sc = {
+		.gfp_mask = gfp_mask,
+		.swap_cluster_max = SWAP_CLUSTER_MAX,
+		.order = order,
+	};
+
+	for (priority = DEF_PRIORITY; priority >= 0; priority--) {
+		sc.nr_scanned = 0;
+		nr_reclaimed += shrink_zones(priority, zones, &sc);
+		if (nr_reclaimed >= sc.swap_cluster_max)
+			return 1;
+	}
+
+	/* top priority shrink_caches still had more to do? don't OOM, then */
+	return sc.all_unreclaimable;
+}
+
+/*
  * For kswapd, balance_pgdat() will work across all this node's zones until
  * they are all at pages_high.
  *