gfp.h 4.6 KB

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  1. #ifndef __LINUX_GFP_H
  2. #define __LINUX_GFP_H
  3. #include <linux/mmzone.h>
  4. #include <linux/stddef.h>
  5. #include <linux/linkage.h>
  6. #include <linux/config.h>
  7. struct vm_area_struct;
  8. /*
  9. * GFP bitmasks..
  10. */
  11. /* Zone modifiers in GFP_ZONEMASK (see linux/mmzone.h - low two bits) */
  12. #define __GFP_DMA 0x01
  13. #define __GFP_HIGHMEM 0x02
  14. /*
  15. * Action modifiers - doesn't change the zoning
  16. *
  17. * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
  18. * _might_ fail. This depends upon the particular VM implementation.
  19. *
  20. * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
  21. * cannot handle allocation failures.
  22. *
  23. * __GFP_NORETRY: The VM implementation must not retry indefinitely.
  24. */
  25. #define __GFP_WAIT 0x10u /* Can wait and reschedule? */
  26. #define __GFP_HIGH 0x20u /* Should access emergency pools? */
  27. #define __GFP_IO 0x40u /* Can start physical IO? */
  28. #define __GFP_FS 0x80u /* Can call down to low-level FS? */
  29. #define __GFP_COLD 0x100u /* Cache-cold page required */
  30. #define __GFP_NOWARN 0x200u /* Suppress page allocation failure warning */
  31. #define __GFP_REPEAT 0x400u /* Retry the allocation. Might fail */
  32. #define __GFP_NOFAIL 0x800u /* Retry for ever. Cannot fail */
  33. #define __GFP_NORETRY 0x1000u /* Do not retry. Might fail */
  34. #define __GFP_NO_GROW 0x2000u /* Slab internal usage */
  35. #define __GFP_COMP 0x4000u /* Add compound page metadata */
  36. #define __GFP_ZERO 0x8000u /* Return zeroed page on success */
  37. #define __GFP_NOMEMALLOC 0x10000u /* Don't use emergency reserves */
  38. #define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */
  39. #define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1)
  40. /* if you forget to add the bitmask here kernel will crash, period */
  41. #define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
  42. __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
  43. __GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \
  44. __GFP_NOMEMALLOC)
  45. #define GFP_ATOMIC (__GFP_HIGH)
  46. #define GFP_NOIO (__GFP_WAIT)
  47. #define GFP_NOFS (__GFP_WAIT | __GFP_IO)
  48. #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS)
  49. #define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS)
  50. #define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HIGHMEM)
  51. /* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
  52. platforms, used as appropriate on others */
  53. #define GFP_DMA __GFP_DMA
  54. /*
  55. * There is only one page-allocator function, and two main namespaces to
  56. * it. The alloc_page*() variants return 'struct page *' and as such
  57. * can allocate highmem pages, the *get*page*() variants return
  58. * virtual kernel addresses to the allocated page(s).
  59. */
  60. /*
  61. * We get the zone list from the current node and the gfp_mask.
  62. * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
  63. *
  64. * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
  65. * optimized to &contig_page_data at compile-time.
  66. */
  67. #ifndef HAVE_ARCH_FREE_PAGE
  68. static inline void arch_free_page(struct page *page, int order) { }
  69. #endif
  70. extern struct page *
  71. FASTCALL(__alloc_pages(unsigned int, unsigned int, struct zonelist *));
  72. static inline struct page *alloc_pages_node(int nid, unsigned int __nocast gfp_mask,
  73. unsigned int order)
  74. {
  75. if (unlikely(order >= MAX_ORDER))
  76. return NULL;
  77. return __alloc_pages(gfp_mask, order,
  78. NODE_DATA(nid)->node_zonelists + (gfp_mask & GFP_ZONEMASK));
  79. }
  80. #ifdef CONFIG_NUMA
  81. extern struct page *alloc_pages_current(unsigned int __nocast gfp_mask, unsigned order);
  82. static inline struct page *
  83. alloc_pages(unsigned int __nocast gfp_mask, unsigned int order)
  84. {
  85. if (unlikely(order >= MAX_ORDER))
  86. return NULL;
  87. return alloc_pages_current(gfp_mask, order);
  88. }
  89. extern struct page *alloc_page_vma(unsigned __nocast gfp_mask,
  90. struct vm_area_struct *vma, unsigned long addr);
  91. #else
  92. #define alloc_pages(gfp_mask, order) \
  93. alloc_pages_node(numa_node_id(), gfp_mask, order)
  94. #define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
  95. #endif
  96. #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
  97. extern unsigned long FASTCALL(__get_free_pages(unsigned int __nocast gfp_mask, unsigned int order));
  98. extern unsigned long FASTCALL(get_zeroed_page(unsigned int __nocast gfp_mask));
  99. #define __get_free_page(gfp_mask) \
  100. __get_free_pages((gfp_mask),0)
  101. #define __get_dma_pages(gfp_mask, order) \
  102. __get_free_pages((gfp_mask) | GFP_DMA,(order))
  103. extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
  104. extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
  105. extern void FASTCALL(free_hot_page(struct page *page));
  106. extern void FASTCALL(free_cold_page(struct page *page));
  107. #define __free_page(page) __free_pages((page), 0)
  108. #define free_page(addr) free_pages((addr),0)
  109. void page_alloc_init(void);
  110. #endif /* __LINUX_GFP_H */