include/linux/cma.h

   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 #ifdef CONFIG_CMA_AREAS
  10 #define MAX_CMA_AREAS   CONFIG_CMA_AREAS
  11 #endif
  12
  13 #define CMA_MAX_NAME 64
  14
  15 /*
  16  *  the buddy -- especially pageblock merging and alloc_contig_range()
  17  * -- can deal with only some pageblocks of a higher-order page being
  18  *  MIGRATE_CMA, we can use pageblock_nr_pages.
  19  */
  20 #define CMA_MIN_ALIGNMENT_PAGES pageblock_nr_pages
  21 #define CMA_MIN_ALIGNMENT_BYTES (PAGE_SIZE * CMA_MIN_ALIGNMENT_PAGES)
  22
  23 struct cma;
  24
  25 extern unsigned long totalcma_pages;
  26 extern phys_addr_t cma_get_base(const struct cma *cma);
  27 extern unsigned long cma_get_size(const struct cma *cma);
  28 extern const char *cma_get_name(const struct cma *cma);
  29
  30 extern int __init cma_declare_contiguous_nid(phys_addr_t base,
  31                         phys_addr_t size, phys_addr_t limit,
  32                         phys_addr_t alignment, unsigned int order_per_bit,
  33                         bool fixed, const char *name, struct cma **res_cma,
  34                         int nid);
  35 static inline int __init cma_declare_contiguous(phys_addr_t base,
  36                         phys_addr_t size, phys_addr_t limit,
  37                         phys_addr_t alignment, unsigned int order_per_bit,
  38                         bool fixed, const char *name, struct cma **res_cma)
  39 {
  40         return cma_declare_contiguous_nid(base, size, limit, alignment,
  41                         order_per_bit, fixed, name, res_cma, NUMA_NO_NODE);
  42 }
  43 extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
  44                                         unsigned int order_per_bit,
  45                                         const char *name,
  46                                         struct cma **res_cma);
  47 extern struct page *cma_alloc(struct cma *cma, unsigned long count, unsigned int align,
  48                               bool no_warn);
  49 extern bool cma_pages_valid(struct cma *cma, const struct page *pages, unsigned long count);
  50 extern bool cma_release(struct cma *cma, const struct page *pages, unsigned long count);
  51
  52 extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data);
  53
  54 extern void cma_reserve_pages_on_error(struct cma *cma);
  55
  56 #ifdef CONFIG_CMA
  57 struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp);
  58 bool cma_free_folio(struct cma *cma, const struct folio *folio);
  59 #else
  60 static inline struct folio *cma_alloc_folio(struct cma *cma, int order, gfp_t gfp)
  61 {
  62         return NULL;
  63 }
  64
  65 static inline bool cma_free_folio(struct cma *cma, const struct folio *folio)
  66 {
  67         return false;
  68 }
  69 #endif
  70
  71 #endif