[XFS] Add a debug flag for allocations which are known to be larger than
one page.

SGI-PV: 955302
SGI-Modid: xfs-linux-melb:xfs-kern:26800a

Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
diff --git a/fs/xfs/linux-2.6/kmem.c b/fs/xfs/linux-2.6/kmem.c
index aba7fcf..f77fe5c 100644
--- a/fs/xfs/linux-2.6/kmem.c
+++ b/fs/xfs/linux-2.6/kmem.c
@@ -34,6 +34,14 @@
 	gfp_t	lflags = kmem_flags_convert(flags);
 	void	*ptr;
 
+#ifdef DEBUG
+	if (unlikely(!(flags & KM_LARGE) && (size > PAGE_SIZE))) {
+		printk(KERN_WARNING "Large %s attempt, size=%ld\n",
+			__FUNCTION__, (long)size);
+		dump_stack();
+	}
+#endif
+
 	do {
 		if (size < MAX_SLAB_SIZE || retries > MAX_VMALLOCS)
 			ptr = kmalloc(size, lflags);
diff --git a/fs/xfs/linux-2.6/kmem.h b/fs/xfs/linux-2.6/kmem.h
index 0e8293c..6d24274 100644
--- a/fs/xfs/linux-2.6/kmem.h
+++ b/fs/xfs/linux-2.6/kmem.h
@@ -30,6 +30,7 @@
 #define KM_NOSLEEP	0x0002u
 #define KM_NOFS		0x0004u
 #define KM_MAYFAIL	0x0008u
+#define KM_LARGE	0x0010u
 
 /*
  * We use a special process flag to avoid recursive callbacks into
@@ -41,7 +42,7 @@
 {
 	gfp_t	lflags;
 
-	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL));
+	BUG_ON(flags & ~(KM_SLEEP|KM_NOSLEEP|KM_NOFS|KM_MAYFAIL|KM_LARGE));
 
 	if (flags & KM_NOSLEEP) {
 		lflags = GFP_ATOMIC | __GFP_NOWARN;
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 247adce..58b6599 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -768,7 +768,7 @@
 	_xfs_buf_initialize(bp, target, 0, len, 0);
 
  try_again:
-	data = kmem_alloc(malloc_len, KM_SLEEP | KM_MAYFAIL);
+	data = kmem_alloc(malloc_len, KM_SLEEP | KM_MAYFAIL | KM_LARGE);
 	if (unlikely(data == NULL))
 		goto fail_free_buf;