[PATCH 1/2] Add vzalloc shortcut

[Dave Young <hidave.darkstar@gmail.com>]

Add vzalloc for convinience of vmalloc-then-memset-zero case 

Use __GFP_ZERO in vzalloc to zero fill the allocated memory.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
---
 include/linux/vmalloc.h |    1 +
 mm/vmalloc.c            |   13 +++++++++++++
 2 files changed, 14 insertions(+)

--- linux-2.6.orig/include/linux/vmalloc.h	2010-08-22 15:31:38.000000000 +0800
+++ linux-2.6/include/linux/vmalloc.h	2010-10-16 10:50:54.739996121 +0800
@@ -53,6 +53,7 @@ static inline void vmalloc_init(void)
 #endif
 
 extern void *vmalloc(unsigned long size);
+extern void *vzalloc(unsigned long size);
 extern void *vmalloc_user(unsigned long size);
 extern void *vmalloc_node(unsigned long size, int node);
 extern void *vmalloc_exec(unsigned long size);
--- linux-2.6.orig/mm/vmalloc.c	2010-08-22 15:31:39.000000000 +0800
+++ linux-2.6/mm/vmalloc.c	2010-10-16 10:51:57.126665918 +0800
@@ -1604,6 +1604,19 @@ void *vmalloc(unsigned long size)
 EXPORT_SYMBOL(vmalloc);
 
 /**
+ *	vzalloc  -  allocate virtually contiguous memory with zero filled
+ *	@size:		allocation size
+ *	Allocate enough pages to cover @size from the page level
+ *	allocator and map them into contiguous kernel virtual space.
+ */
+void *vzalloc(unsigned long size)
+{
+	return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
+				PAGE_KERNEL, -1, __builtin_return_address(0));
+}
+EXPORT_SYMBOL(vzalloc);
+
+/**
  * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
  * @size: allocation size
  *