Commit a8749a35 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

mm: vmalloc: introduce array allocation functions 



Linux has dozens of occurrences of vmalloc(array_size()) and
vzalloc(array_size()).  Allow to simplify the code by providing
vmalloc_array and vcalloc, as well as the underscored variants that let
the caller specify the GFP flags.

Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 0564eeb7

include/linux/vmalloc.h

+5 −0
Original line number Diff line number Diff line
@@ -159,6 +159,11 @@ void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask, 
		int node, const void *caller) __alloc_size(1);

void *vmalloc_no_huge(unsigned long size) __alloc_size(1);



extern void *__vmalloc_array(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);

extern void *vmalloc_array(size_t n, size_t size) __alloc_size(1, 2);

extern void *__vcalloc(size_t n, size_t size, gfp_t flags) __alloc_size(1, 2);

extern void *vcalloc(size_t n, size_t size) __alloc_size(1, 2);



extern void vfree(const void *addr);

extern void vfree_atomic(const void *addr);

mm/util.c

+50 −0
Original line number Diff line number Diff line
@@ -647,6 +647,56 @@ void *kvrealloc(const void *p, size_t oldsize, size_t newsize, gfp_t flags) 
}

EXPORT_SYMBOL(kvrealloc);



/**

 * __vmalloc_array - allocate memory for a virtually contiguous array.

 * @n: number of elements.

 * @size: element size.

 * @flags: the type of memory to allocate (see kmalloc).

 */

void *__vmalloc_array(size_t n, size_t size, gfp_t flags)

{

	size_t bytes;



	if (unlikely(check_mul_overflow(n, size, &bytes)))

		return NULL;

	return __vmalloc(bytes, flags);

}

EXPORT_SYMBOL(__vmalloc_array);



/**

 * vmalloc_array - allocate memory for a virtually contiguous array.

 * @n: number of elements.

 * @size: element size.

 */

void *vmalloc_array(size_t n, size_t size)

{

	return __vmalloc_array(n, size, GFP_KERNEL);

}

EXPORT_SYMBOL(vmalloc_array);



/**

 * __vcalloc - allocate and zero memory for a virtually contiguous array.

 * @n: number of elements.

 * @size: element size.

 * @flags: the type of memory to allocate (see kmalloc).

 */

void *__vcalloc(size_t n, size_t size, gfp_t flags)

{

	return __vmalloc_array(n, size, flags | __GFP_ZERO);

}

EXPORT_SYMBOL(__vcalloc);



/**

 * vcalloc - allocate and zero memory for a virtually contiguous array.

 * @n: number of elements.

 * @size: element size.

 */

void *vcalloc(size_t n, size_t size)

{

	return __vmalloc_array(n, size, GFP_KERNEL | __GFP_ZERO);

}

EXPORT_SYMBOL(vcalloc);



/* Neutral page->mapping pointer to address_space or anon_vma or other */

void *page_rmapping(struct page *page)

{