mm: make some struct page's const

These uses are read-only and in a subsequent patch I have a const struct
page in my hand...

[akpm@linux-foundation.org: fix warnings in lowmem_page_address()]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ian Campbell 2011-07-25 17:11:51 -07:00 committed by Linus Torvalds
parent ee8f248d26
commit 33dd4e0ec9
2 changed files with 7 additions and 7 deletions

View file

@ -637,7 +637,7 @@ static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
#define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
#define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)
static inline enum zone_type page_zonenum(struct page *page)
static inline enum zone_type page_zonenum(const struct page *page)
{
return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
}
@ -665,15 +665,15 @@ static inline int zone_to_nid(struct zone *zone)
}
#ifdef NODE_NOT_IN_PAGE_FLAGS
extern int page_to_nid(struct page *page);
extern int page_to_nid(const struct page *page);
#else
static inline int page_to_nid(struct page *page)
static inline int page_to_nid(const struct page *page)
{
return (page->flags >> NODES_PGSHIFT) & NODES_MASK;
}
#endif
static inline struct zone *page_zone(struct page *page)
static inline struct zone *page_zone(const struct page *page)
{
return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
}
@ -718,9 +718,9 @@ static inline void set_page_links(struct page *page, enum zone_type zone,
*/
#include <linux/vmstat.h>
static __always_inline void *lowmem_page_address(struct page *page)
static __always_inline void *lowmem_page_address(const struct page *page)
{
return __va(PFN_PHYS(page_to_pfn(page)));
return __va(PFN_PHYS(page_to_pfn((struct page *)page)));
}
#if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)

View file

@ -40,7 +40,7 @@ static u8 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
static u16 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
#endif
int page_to_nid(struct page *page)
int page_to_nid(const struct page *page)
{
return section_to_node_table[page_to_section(page)];
}