1 #ifndef __LINUX_GFP_H 2 #define __LINUX_GFP_H 3 4 #include <linux/mmzone.h> 5 #include <linux/stddef.h> 6 #include <linux/linkage.h> 7 #include <linux/config.h> 8 9 struct vm_area_struct; 10 11 /* 12 * GFP bitmasks.. 13 */ 14 /* Zone modifiers in GFP_ZONEMASK (see linux/mmzone.h - low two bits) */ 15 #define __GFP_DMA 0x01 16 #define __GFP_HIGHMEM 0x02 17 18 /* 19 * Action modifiers - doesn't change the zoning 20 * 21 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt 22 * _might_ fail. This depends upon the particular VM implementation. 23 * 24 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller 25 * cannot handle allocation failures. 26 * 27 * __GFP_NORETRY: The VM implementation must not retry indefinitely. 28 */ 29 #define __GFP_WAIT 0x10u /* Can wait and reschedule? */ 30 #define __GFP_HIGH 0x20u /* Should access emergency pools? */ 31 #define __GFP_IO 0x40u /* Can start physical IO? */ 32 #define __GFP_FS 0x80u /* Can call down to low-level FS? */ 33 #define __GFP_COLD 0x100u /* Cache-cold page required */ 34 #define __GFP_NOWARN 0x200u /* Suppress page allocation failure warning */ 35 #define __GFP_REPEAT 0x400u /* Retry the allocation. Might fail */ 36 #define __GFP_NOFAIL 0x800u /* Retry for ever. Cannot fail */ 37 #define __GFP_NORETRY 0x1000u /* Do not retry. Might fail */ 38 #define __GFP_NO_GROW 0x2000u /* Slab internal usage */ 39 #define __GFP_COMP 0x4000u /* Add compound page metadata */ 40 #define __GFP_ZERO 0x8000u /* Return zeroed page on success */ 41 #define __GFP_NOMEMALLOC 0x10000u /* Don't use emergency reserves */ 42 43 #define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */ 44 #define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1) 45 46 /* if you forget to add the bitmask here kernel will crash, period */ 47 #define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \ 48 __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \ 49 __GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \ 50 __GFP_NOMEMALLOC) 51 52 #define GFP_ATOMIC (__GFP_HIGH) 53 #define GFP_NOIO (__GFP_WAIT) 54 #define GFP_NOFS (__GFP_WAIT | __GFP_IO) 55 #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS) 56 #define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS) 57 #define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HIGHMEM) 58 59 /* Flag - indicates that the buffer will be suitable for DMA. Ignored on some 60 platforms, used as appropriate on others */ 61 62 #define GFP_DMA __GFP_DMA 63 64 65 /* 66 * There is only one page-allocator function, and two main namespaces to 67 * it. The alloc_page*() variants return 'struct page *' and as such 68 * can allocate highmem pages, the *get*page*() variants return 69 * virtual kernel addresses to the allocated page(s). 70 */ 71 72 /* 73 * We get the zone list from the current node and the gfp_mask. 74 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones. 75 * 76 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets 77 * optimized to &contig_page_data at compile-time. 78 */ 79 80 #ifndef HAVE_ARCH_FREE_PAGE 81 static inline void arch_free_page(struct page *page, int order) { } 82 #endif 83 84 extern struct page * 85 FASTCALL(__alloc_pages(unsigned int, unsigned int, struct zonelist *)); 86 87 static inline struct page *alloc_pages_node(int nid, unsigned int __nocast gfp_mask, 88 unsigned int order) 89 { 90 if (unlikely(order >= MAX_ORDER)) 91 return NULL; 92 93 return __alloc_pages(gfp_mask, order, 94 NODE_DATA(nid)->node_zonelists + (gfp_mask & GFP_ZONEMASK)); 95 } 96 97 #ifdef CONFIG_NUMA 98 extern struct page *alloc_pages_current(unsigned int __nocast gfp_mask, unsigned order); 99 100 static inline struct page * 101 alloc_pages(unsigned int __nocast gfp_mask, unsigned int order) 102 { 103 if (unlikely(order >= MAX_ORDER)) 104 return NULL; 105 106 return alloc_pages_current(gfp_mask, order); 107 } 108 extern struct page *alloc_page_vma(unsigned __nocast gfp_mask, 109 struct vm_area_struct *vma, unsigned long addr); 110 #else 111 #define alloc_pages(gfp_mask, order) \ 112 alloc_pages_node(numa_node_id(), gfp_mask, order) 113 #define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0) 114 #endif 115 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0) 116 117 extern unsigned long FASTCALL(__get_free_pages(unsigned int __nocast gfp_mask, unsigned int order)); 118 extern unsigned long FASTCALL(get_zeroed_page(unsigned int __nocast gfp_mask)); 119 120 #define __get_free_page(gfp_mask) \ 121 __get_free_pages((gfp_mask),0) 122 123 #define __get_dma_pages(gfp_mask, order) \ 124 __get_free_pages((gfp_mask) | GFP_DMA,(order)) 125 126 extern void FASTCALL(__free_pages(struct page *page, unsigned int order)); 127 extern void FASTCALL(free_pages(unsigned long addr, unsigned int order)); 128 extern void FASTCALL(free_hot_page(struct page *page)); 129 extern void FASTCALL(free_cold_page(struct page *page)); 130 131 #define __free_page(page) __free_pages((page), 0) 132 #define free_page(addr) free_pages((addr),0) 133 134 void page_alloc_init(void); 135 136 #endif /* __LINUX_GFP_H */ 137