xref: /linux/include/linux/cma.h (revision 908fc4c2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __CMA_H__
3 #define __CMA_H__
4 
5 #include <linux/init.h>
6 #include <linux/types.h>
7 #include <linux/numa.h>
8 
9 /*
10  * There is always at least global CMA area and a few optional
11  * areas configured in kernel .config.
12  */
13 #ifdef CONFIG_CMA_AREAS
14 #define MAX_CMA_AREAS	(1 + CONFIG_CMA_AREAS)
15 #endif
16 
17 #define CMA_MAX_NAME 64
18 
19 /*
20  *  the buddy -- especially pageblock merging and alloc_contig_range()
21  * -- can deal with only some pageblocks of a higher-order page being
22  *  MIGRATE_CMA, we can use pageblock_nr_pages.
23  */
24 #define CMA_MIN_ALIGNMENT_PAGES pageblock_nr_pages
25 #define CMA_MIN_ALIGNMENT_BYTES (PAGE_SIZE * CMA_MIN_ALIGNMENT_PAGES)
26 
27 struct cma;
28 
29 extern unsigned long totalcma_pages;
30 extern phys_addr_t cma_get_base(const struct cma *cma);
31 extern unsigned long cma_get_size(const struct cma *cma);
32 extern const char *cma_get_name(const struct cma *cma);
33 
34 extern int __init cma_declare_contiguous_nid(phys_addr_t base,
35 			phys_addr_t size, phys_addr_t limit,
36 			phys_addr_t alignment, unsigned int order_per_bit,
37 			bool fixed, const char *name, struct cma **res_cma,
38 			int nid);
39 static inline int __init cma_declare_contiguous(phys_addr_t base,
40 			phys_addr_t size, phys_addr_t limit,
41 			phys_addr_t alignment, unsigned int order_per_bit,
42 			bool fixed, const char *name, struct cma **res_cma)
43 {
44 	return cma_declare_contiguous_nid(base, size, limit, alignment,
45 			order_per_bit, fixed, name, res_cma, NUMA_NO_NODE);
46 }
47 extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
48 					unsigned int order_per_bit,
49 					const char *name,
50 					struct cma **res_cma);
51 extern struct page *cma_alloc(struct cma *cma, unsigned long count, unsigned int align,
52 			      bool no_warn);
53 extern bool cma_pages_valid(struct cma *cma, const struct page *pages, unsigned long count);
54 extern bool cma_release(struct cma *cma, const struct page *pages, unsigned long count);
55 
56 extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data);
57 
58 extern void cma_reserve_pages_on_error(struct cma *cma);
59 #endif
60