original_kernel/include/asm-generic/memory_model.h

87 lines
2.2 KiB
C

#ifndef __ASM_MEMORY_MODEL_H
#define __ASM_MEMORY_MODEL_H
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#if defined(CONFIG_FLATMEM)
#ifndef ARCH_PFN_OFFSET
#define ARCH_PFN_OFFSET (0UL)
#endif
#elif defined(CONFIG_DISCONTIGMEM)
#ifndef arch_pfn_to_nid
#define arch_pfn_to_nid(pfn) pfn_to_nid(pfn)
#endif
#ifndef arch_local_page_offset
#define arch_local_page_offset(pfn, nid) \
((pfn) - NODE_DATA(nid)->node_start_pfn)
#endif
#endif /* CONFIG_DISCONTIGMEM */
/*
* supports 3 memory models.
*/
#if defined(CONFIG_FLATMEM)
#define __pfn_to_page(pfn) (mem_map + ((pfn) - ARCH_PFN_OFFSET))
#define __page_to_pfn(page) ((unsigned long)((page) - mem_map) + \
ARCH_PFN_OFFSET)
#elif defined(CONFIG_DISCONTIGMEM)
#define __pfn_to_page(pfn) \
({ unsigned long __pfn = (pfn); \
unsigned long __nid = arch_pfn_to_nid(pfn); \
NODE_DATA(__nid)->node_mem_map + arch_local_page_offset(__pfn, __nid);\
})
#define __page_to_pfn(pg) \
({ struct page *__pg = (pg); \
struct pglist_data *__pgdat = NODE_DATA(page_to_nid(__pg)); \
(unsigned long)(__pg - __pgdat->node_mem_map) + \
__pgdat->node_start_pfn; \
})
#elif defined(CONFIG_SPARSEMEM_VMEMMAP)
/* memmap is virtually contigious. */
#define __pfn_to_page(pfn) (vmemmap + (pfn))
#define __page_to_pfn(page) ((page) - vmemmap)
#elif defined(CONFIG_SPARSEMEM)
/*
* Note: section's mem_map is encorded to reflect its start_pfn.
* section[i].section_mem_map == mem_map's address - start_pfn;
*/
#define __page_to_pfn(pg) \
({ struct page *__pg = (pg); \
int __sec = page_to_section(__pg); \
(unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
})
#define __pfn_to_page(pfn) \
({ unsigned long __pfn = (pfn); \
struct mem_section *__sec = __pfn_to_section(__pfn); \
__section_mem_map_addr(__sec) + __pfn; \
})
#endif /* CONFIG_FLATMEM/DISCONTIGMEM/SPARSEMEM */
#ifdef CONFIG_OUT_OF_LINE_PFN_TO_PAGE
struct page;
/* this is useful when inlined pfn_to_page is too big */
extern struct page *pfn_to_page(unsigned long pfn);
extern unsigned long page_to_pfn(struct page *page);
#else
#define page_to_pfn __page_to_pfn
#define pfn_to_page __pfn_to_page
#endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif