xref: /linux/mm/cma.h (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __MM_CMA_H__
3 #define __MM_CMA_H__
4 
5 #include <linux/debugfs.h>
6 #include <linux/kobject.h>
7 
8 struct cma_kobject {
9 	struct kobject kobj;
10 	struct cma *cma;
11 };
12 
13 /*
14  * Multi-range support. This can be useful if the size of the allocation
15  * is not expected to be larger than the alignment (like with hugetlb_cma),
16  * and the total amount of memory requested, while smaller than the total
17  * amount of memory available, is large enough that it doesn't fit in a
18  * single physical memory range because of memory holes.
19  *
20  * Fields:
21  *   @base_pfn: physical address of range
22  *   @early_pfn: first PFN not reserved through cma_reserve_early
23  *   @count: size of range
24  *   @bitmap: bitmap of allocated (1 << order_per_bit)-sized chunks.
25  */
26 struct cma_memrange {
27 	unsigned long base_pfn;
28 	unsigned long count;
29 	union {
30 		unsigned long early_pfn;
31 		unsigned long *bitmap;
32 	};
33 #ifdef CONFIG_CMA_DEBUGFS
34 	struct debugfs_u32_array dfs_bitmap;
35 #endif
36 };
37 #define CMA_MAX_RANGES 8
38 
39 struct cma {
40 	unsigned long   count;
41 	unsigned long	available_count;
42 	unsigned int order_per_bit; /* Order of pages represented by one bit */
43 	spinlock_t	lock;
44 	struct mutex alloc_mutex;
45 #ifdef CONFIG_CMA_DEBUGFS
46 	struct hlist_head mem_head;
47 	spinlock_t mem_head_lock;
48 #endif
49 	char name[CMA_MAX_NAME];
50 	int nranges;
51 	struct cma_memrange ranges[CMA_MAX_RANGES];
52 #ifdef CONFIG_CMA_SYSFS
53 	/* the number of CMA page successful allocations */
54 	atomic64_t nr_pages_succeeded;
55 	/* the number of CMA page allocation failures */
56 	atomic64_t nr_pages_failed;
57 	/* the number of CMA page released */
58 	atomic64_t nr_pages_released;
59 	/* kobject requires dynamic object */
60 	struct cma_kobject *cma_kobj;
61 #endif
62 	unsigned long flags;
63 	/* NUMA node (NUMA_NO_NODE if unspecified) */
64 	int nid;
65 };
66 
67 enum cma_flags {
68 	CMA_RESERVE_PAGES_ON_ERROR,
69 	CMA_ZONES_VALID,
70 	CMA_ZONES_INVALID,
71 	CMA_ACTIVATED,
72 };
73 
74 extern struct cma cma_areas[MAX_CMA_AREAS];
75 extern unsigned int cma_area_count;
76 
cma_bitmap_maxno(struct cma * cma,struct cma_memrange * cmr)77 static inline unsigned long cma_bitmap_maxno(struct cma *cma,
78 		struct cma_memrange *cmr)
79 {
80 	return cmr->count >> cma->order_per_bit;
81 }
82 
83 #ifdef CONFIG_CMA_SYSFS
84 void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_pages);
85 void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_pages);
86 void cma_sysfs_account_release_pages(struct cma *cma, unsigned long nr_pages);
87 #else
cma_sysfs_account_success_pages(struct cma * cma,unsigned long nr_pages)88 static inline void cma_sysfs_account_success_pages(struct cma *cma,
89 						   unsigned long nr_pages) {};
cma_sysfs_account_fail_pages(struct cma * cma,unsigned long nr_pages)90 static inline void cma_sysfs_account_fail_pages(struct cma *cma,
91 						unsigned long nr_pages) {};
cma_sysfs_account_release_pages(struct cma * cma,unsigned long nr_pages)92 static inline void cma_sysfs_account_release_pages(struct cma *cma,
93 						   unsigned long nr_pages) {};
94 #endif
95 #endif
96