gfp.h 4.5 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_BITS_SHIFT 16 /* Room for 16 __GFP_FOO bits */
  38. #define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1)
  39. /* if you forget to add the bitmask here kernel will crash, period */
  40. #define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
  41. __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
  42. __GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP)
  43. #define GFP_ATOMIC (__GFP_HIGH)
  44. #define GFP_NOIO (__GFP_WAIT)
  45. #define GFP_NOFS (__GFP_WAIT | __GFP_IO)
  46. #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS)
  47. #define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS)
  48. #define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HIGHMEM)
  49. /* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
  50. platforms, used as appropriate on others */
  51. #define GFP_DMA __GFP_DMA
  52. /*
  53. * There is only one page-allocator function, and two main namespaces to
  54. * it. The alloc_page*() variants return 'struct page *' and as such
  55. * can allocate highmem pages, the *get*page*() variants return
  56. * virtual kernel addresses to the allocated page(s).
  57. */
  58. /*
  59. * We get the zone list from the current node and the gfp_mask.
  60. * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
  61. *
  62. * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
  63. * optimized to &contig_page_data at compile-time.
  64. */
  65. #ifndef HAVE_ARCH_FREE_PAGE
  66. static inline void arch_free_page(struct page *page, int order) { }
  67. #endif
  68. extern struct page *
  69. FASTCALL(__alloc_pages(unsigned int, unsigned int, struct zonelist *));
  70. static inline struct page *alloc_pages_node(int nid, unsigned int __nocast gfp_mask,
  71. unsigned int order)
  72. {
  73. if (unlikely(order >= MAX_ORDER))
  74. return NULL;
  75. return __alloc_pages(gfp_mask, order,
  76. NODE_DATA(nid)->node_zonelists + (gfp_mask & GFP_ZONEMASK));
  77. }
  78. #ifdef CONFIG_NUMA
  79. extern struct page *alloc_pages_current(unsigned int __nocast gfp_mask, unsigned order);
  80. static inline struct page *
  81. alloc_pages(unsigned int __nocast gfp_mask, unsigned int order)
  82. {
  83. if (unlikely(order >= MAX_ORDER))
  84. return NULL;
  85. return alloc_pages_current(gfp_mask, order);
  86. }
  87. extern struct page *alloc_page_vma(unsigned __nocast gfp_mask,
  88. struct vm_area_struct *vma, unsigned long addr);
  89. #else
  90. #define alloc_pages(gfp_mask, order) \
  91. alloc_pages_node(numa_node_id(), gfp_mask, order)
  92. #define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
  93. #endif
  94. #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
  95. extern unsigned long FASTCALL(__get_free_pages(unsigned int __nocast gfp_mask, unsigned int order));
  96. extern unsigned long FASTCALL(get_zeroed_page(unsigned int __nocast gfp_mask));
  97. #define __get_free_page(gfp_mask) \
  98. __get_free_pages((gfp_mask),0)
  99. #define __get_dma_pages(gfp_mask, order) \
  100. __get_free_pages((gfp_mask) | GFP_DMA,(order))
  101. extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
  102. extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
  103. extern void FASTCALL(free_hot_page(struct page *page));
  104. extern void FASTCALL(free_cold_page(struct page *page));
  105. #define __free_page(page) __free_pages((page), 0)
  106. #define free_page(addr) free_pages((addr),0)
  107. void page_alloc_init(void);
  108. #endif /* __LINUX_GFP_H */