xref: /linux-6.15/include/linux/genalloc.h (revision 40efcb05)
1 /*
2  * Basic general purpose allocator for managing special purpose memory
3  * not managed by the regular kmalloc/kfree interface.
4  * Uses for this includes on-device special memory, uncached memory
5  * etc.
6  *
7  * This source code is licensed under the GNU General Public License,
8  * Version 2.  See the file COPYING for more details.
9  */
10 
11 
12 /*
13  *  General purpose special memory pool descriptor.
14  */
15 struct gen_pool {
16 	rwlock_t lock;
17 	struct list_head chunks;	/* list of chunks in this pool */
18 	int min_alloc_order;		/* minimum allocation order */
19 };
20 
21 /*
22  *  General purpose special memory pool chunk descriptor.
23  */
24 struct gen_pool_chunk {
25 	spinlock_t lock;
26 	struct list_head next_chunk;	/* next chunk in pool */
27 	unsigned long start_addr;	/* starting address of memory chunk */
28 	unsigned long end_addr;		/* ending address of memory chunk */
29 	unsigned long bits[0];		/* bitmap for allocating memory chunk */
30 };
31 
32 extern struct gen_pool *gen_pool_create(int, int);
33 extern int gen_pool_add(struct gen_pool *, unsigned long, size_t, int);
34 extern void gen_pool_destroy(struct gen_pool *);
35 extern unsigned long gen_pool_alloc(struct gen_pool *, size_t);
36 extern void gen_pool_free(struct gen_pool *, unsigned long, size_t);
37