Commit 67de6482 authored by Andy Whitcroft's avatar Andy Whitcroft Committed by Linus Torvalds
Browse files

[PATCH] squash duplicate page_to_pfn and pfn_to_page 



We have architectures where the size of page_to_pfn and pfn_to_page are
significant enough to overall image size that they wish to push them out of
line.  However, in the process we have grown a second copy of the
implementation of each of these routines for each memory model.  Share the
implmentation exposing it either inline or out-of-line as required.

Signed-off-by: default avatarAndy Whitcroft <apw@shadowen.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 6811378e

include/asm-generic/memory_model.h

+15 −12
Original line number Diff line number Diff line
@@ -23,29 +23,23 @@ 


#endif /* CONFIG_DISCONTIGMEM */



#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

/*

 * 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) + \

#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)			\

#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)							\

#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) +			\
@@ -57,18 +51,27 @@ extern unsigned long page_to_pfn(struct page *page); 
 * 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)					\

#define __page_to_pfn(pg)					\

({	struct page *__pg = (pg);				\

	int __sec = page_to_section(__pg);			\

	__pg - __section_mem_map_addr(__nr_to_section(__sec));	\

})



#define pfn_to_page(pfn)				\

#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__ */

mm/page_alloc.c

+2 −30
Original line number Diff line number Diff line
@@ -2879,42 +2879,14 @@ void *__init alloc_large_system_hash(const char *tablename, 
}



#ifdef CONFIG_OUT_OF_LINE_PFN_TO_PAGE

/*

 * pfn <-> page translation. out-of-line version.

 * (see asm-generic/memory_model.h)

 */

#if defined(CONFIG_FLATMEM)

struct page *pfn_to_page(unsigned long pfn)

{

	return mem_map + (pfn - ARCH_PFN_OFFSET);

}

unsigned long page_to_pfn(struct page *page)

{

	return (page - mem_map) + ARCH_PFN_OFFSET;

}

#elif defined(CONFIG_DISCONTIGMEM)

struct page *pfn_to_page(unsigned long pfn)

{

	int nid = arch_pfn_to_nid(pfn);

	return NODE_DATA(nid)->node_mem_map + arch_local_page_offset(pfn,nid);

	return __pfn_to_page(pfn);

}

unsigned long page_to_pfn(struct page *page)

{

	struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));

	return (page - pgdat->node_mem_map) + pgdat->node_start_pfn;

}

#elif defined(CONFIG_SPARSEMEM)

struct page *pfn_to_page(unsigned long pfn)

{

	return __section_mem_map_addr(__pfn_to_section(pfn)) + pfn;

}



unsigned long page_to_pfn(struct page *page)

{

	long section_id = page_to_section(page);

	return page - __section_mem_map_addr(__nr_to_section(section_id));

	return __page_to_pfn(page);

}

#endif /* CONFIG_FLATMEM/DISCONTIGMME/SPARSEMEM */

EXPORT_SYMBOL(pfn_to_page);

EXPORT_SYMBOL(page_to_pfn);

#endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */

CRA Git | Maintained and supported by SUSTech CRA and CCSE