Commit b26981c8 authored by Zhao Qiang's avatar Zhao Qiang Committed by Scott Wood
Browse files

genalloc:support allocating specific region 



Add new algo for genalloc, it reserve a specific region of
memory

Signed-off-by: default avatarZhao Qiang <qiang.zhao@freescale.com>
Signed-off-by: default avatarScott Wood <scottwood@freescale.com>
parent de2dd0eb

include/linux/genalloc.h

+11 −0
Original line number Diff line number Diff line
@@ -84,6 +84,13 @@ struct genpool_data_align { 
	int align;		/* alignment by bytes for starting address */

};



/*

 *  gen_pool data descriptor for gen_pool_fixed_alloc.

 */

struct genpool_data_fixed {

	unsigned long offset;		/* The offset of the specific region */

};



extern struct gen_pool *gen_pool_create(int, int);

extern phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long);

extern int gen_pool_add_virt(struct gen_pool *, unsigned long, phys_addr_t,
@@ -124,6 +131,10 @@ extern unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size, 
		unsigned long start, unsigned int nr, void *data,

		struct gen_pool *pool);



extern unsigned long gen_pool_fixed_alloc(unsigned long *map,

		unsigned long size, unsigned long start, unsigned int nr,

		void *data, struct gen_pool *pool);



extern unsigned long gen_pool_first_fit_align(unsigned long *map,

		unsigned long size, unsigned long start, unsigned int nr,

		void *data, struct gen_pool *pool);

lib/genalloc.c

+32 −0
Original line number Diff line number Diff line
@@ -555,6 +555,38 @@ unsigned long gen_pool_first_fit_align(unsigned long *map, unsigned long size, 
}

EXPORT_SYMBOL(gen_pool_first_fit_align);



/**

 * gen_pool_fixed_alloc - reserve a specific region

 * @map: The address to base the search on

 * @size: The bitmap size in bits

 * @start: The bitnumber to start searching at

 * @nr: The number of zeroed bits we're looking for

 * @data: data for alignment

 * @pool: pool to get order from

 */

unsigned long gen_pool_fixed_alloc(unsigned long *map, unsigned long size,

		unsigned long start, unsigned int nr, void *data,

		struct gen_pool *pool)

{

	struct genpool_data_fixed *fixed_data;

	int order;

	unsigned long offset_bit;

	unsigned long start_bit;



	fixed_data = data;

	order = pool->min_alloc_order;

	offset_bit = fixed_data->offset >> order;

	if (WARN_ON(fixed_data->offset & (1UL << order - 1)))

		return size;



	start_bit = bitmap_find_next_zero_area(map, size,

			start + offset_bit, nr, 0);

	if (start_bit != offset_bit)

		start_bit = size;

	return start_bit;

}

EXPORT_SYMBOL(gen_pool_fixed_alloc);



/**

 * gen_pool_first_fit_order_align - find the first available region

 * of memory matching the size requirement. The region will be aligned