mm: add vzalloc() and vzalloc_node() helpers

Add vzalloc() and vzalloc_node() to encapsulate the
vmalloc-then-memset-zero operation.

Use __GFP_ZERO to zero fill the allocated memory.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 63a4fe6..a03dcf6 100644 (file)
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -53,8 +53,10 @@ 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 *vzalloc_node(unsigned long size, int node);
 extern void *vmalloc_exec(unsigned long size);
 extern void *vmalloc_32(unsigned long size);
 extern void *vmalloc_32_user(unsigned long size);

diff --git a/mm/nommu.c b/mm/nommu.c
index 88ff091..30b5c20 100644 (file)
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -293,11 +293,58 @@ void *vmalloc(unsigned long size)
 }
 EXPORT_SYMBOL(vmalloc);
 
+/*
+ *     vzalloc - allocate virtually continguos memory with zero fill
+ *
+ *     @size:          allocation size
+ *
+ *     Allocate enough pages to cover @size from the page level
+ *     allocator and map them into continguos kernel virtual space.
+ *     The memory allocated is set to zero.
+ *
+ *     For tight control over page level allocator and protection flags
+ *     use __vmalloc() instead.
+ */
+void *vzalloc(unsigned long size)
+{
+       return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
+                       PAGE_KERNEL);
+}
+EXPORT_SYMBOL(vzalloc);
+
+/**
+ * vmalloc_node - allocate memory on a specific node
+ * @size:      allocation size
+ * @node:      numa node
+ *
+ * Allocate enough pages to cover @size from the page level
+ * allocator and map them into contiguous kernel virtual space.
+ *
+ * For tight control over page level allocator and protection flags
+ * use __vmalloc() instead.
+ */
 void *vmalloc_node(unsigned long size, int node)
 {
        return vmalloc(size);
 }
-EXPORT_SYMBOL(vmalloc_node);
+
+/**
+ * vzalloc_node - allocate memory on a specific node with zero fill
+ * @size:      allocation size
+ * @node:      numa node
+ *
+ * Allocate enough pages to cover @size from the page level
+ * allocator and map them into contiguous kernel virtual space.
+ * The memory allocated is set to zero.
+ *
+ * For tight control over page level allocator and protection flags
+ * use __vmalloc() instead.
+ */
+void *vzalloc_node(unsigned long size, int node)
+{
+       return vzalloc(size);
+}
+EXPORT_SYMBOL(vzalloc_node);
 
 #ifndef PAGE_KERNEL_EXEC
 # define PAGE_KERNEL_EXEC PAGE_KERNEL

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index f492c77..a3d66b3 100644 (file)
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1596,6 +1596,13 @@ void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
 }
 EXPORT_SYMBOL(__vmalloc);
 
+static inline void *__vmalloc_node_flags(unsigned long size,
+                                       int node, gfp_t flags)
+{
+       return __vmalloc_node(size, 1, flags, PAGE_KERNEL,
+                                       node, __builtin_return_address(0));
+}
+
 /**
  *     vmalloc  -  allocate virtually contiguous memory
  *     @size:          allocation size
@@ -1607,11 +1614,27 @@ EXPORT_SYMBOL(__vmalloc);
  */
 void *vmalloc(unsigned long size)
 {
-       return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL,
-                                       -1, __builtin_return_address(0));
+       return __vmalloc_node_flags(size, -1, GFP_KERNEL | __GFP_HIGHMEM);
 }
 EXPORT_SYMBOL(vmalloc);
 
+/**
+ *     vzalloc - allocate virtually contiguous memory with zero fill
+ *     @size:  allocation size
+ *     Allocate enough pages to cover @size from the page level
+ *     allocator and map them into contiguous kernel virtual space.
+ *     The memory allocated is set to zero.
+ *
+ *     For tight control over page level allocator and protection flags
+ *     use __vmalloc() instead.
+ */
+void *vzalloc(unsigned long size)
+{
+       return __vmalloc_node_flags(size, -1,
+                               GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
+}
+EXPORT_SYMBOL(vzalloc);
+
 /**
  * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
  * @size: allocation size
@@ -1653,6 +1676,25 @@ void *vmalloc_node(unsigned long size, int node)
 }
 EXPORT_SYMBOL(vmalloc_node);
 
+/**
+ * vzalloc_node - allocate memory on a specific node with zero fill
+ * @size:      allocation size
+ * @node:      numa node
+ *
+ * Allocate enough pages to cover @size from the page level
+ * allocator and map them into contiguous kernel virtual space.
+ * The memory allocated is set to zero.
+ *
+ * For tight control over page level allocator and protection flags
+ * use __vmalloc_node() instead.
+ */
+void *vzalloc_node(unsigned long size, int node)
+{
+       return __vmalloc_node_flags(size, node,
+                        GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
+}
+EXPORT_SYMBOL(vzalloc_node);
+
 #ifndef PAGE_KERNEL_EXEC
 # define PAGE_KERNEL_EXEC PAGE_KERNEL
 #endif