From: KAMEZAWA Hiroyuki This patch removes zone_mem_map. pfn_to_page uses pgdat, page_to_pfn uses zone. page_to_pfn can use pgdat instead of zone, which is only one user of zone_mem_map. By modifing it, we can remove zone_mem_map. Signed-off-by: KAMEZAWA Hiroyuki Cc: Dave Hansen Cc: Christoph Lameter Signed-off-by: Andrew Morton --- include/asm-alpha/mmzone.h | 3 +-- include/asm-generic/memory_model.h | 10 +++++----- include/linux/mmzone.h | 1 - mm/page_alloc.c | 6 ++---- 4 files changed, 8 insertions(+), 12 deletions(-) diff -puN include/asm-alpha/mmzone.h~remove-zone_mem_map include/asm-alpha/mmzone.h --- devel/include/asm-alpha/mmzone.h~remove-zone_mem_map 2006-03-16 02:09:09.000000000 -0800 +++ devel-akpm/include/asm-alpha/mmzone.h 2006-03-16 02:09:09.000000000 -0800 @@ -83,8 +83,7 @@ PLAT_NODE_DATA_LOCALNR(unsigned long p, pte_t pte; \ unsigned long pfn; \ \ - pfn = ((unsigned long)((page)-page_zone(page)->zone_mem_map)) << 32; \ - pfn += page_zone(page)->zone_start_pfn << 32; \ + pfn = page_to_pfn(page) << 32; \ pte_val(pte) = pfn | pgprot_val(pgprot); \ \ pte; \ diff -puN include/asm-generic/memory_model.h~remove-zone_mem_map include/asm-generic/memory_model.h --- devel/include/asm-generic/memory_model.h~remove-zone_mem_map 2006-03-16 02:09:09.000000000 -0800 +++ devel-akpm/include/asm-generic/memory_model.h 2006-03-16 02:09:09.000000000 -0800 @@ -45,11 +45,11 @@ extern unsigned long page_to_pfn(struct NODE_DATA(__nid)->node_mem_map + arch_local_page_offset(__pfn, __nid);\ }) -#define page_to_pfn(pg) \ -({ struct page *__pg = (pg); \ - struct zone *__zone = page_zone(__pg); \ - (unsigned long)(__pg - __zone->zone_mem_map) + \ - __zone->zone_start_pfn; \ +#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) diff -puN include/linux/mmzone.h~remove-zone_mem_map include/linux/mmzone.h --- devel/include/linux/mmzone.h~remove-zone_mem_map 2006-03-16 02:09:09.000000000 -0800 +++ devel-akpm/include/linux/mmzone.h 2006-03-16 02:09:09.000000000 -0800 @@ -225,7 +225,6 @@ struct zone { * Discontig memory support fields. */ struct pglist_data *zone_pgdat; - struct page *zone_mem_map; /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */ unsigned long zone_start_pfn; diff -puN mm/page_alloc.c~remove-zone_mem_map mm/page_alloc.c --- devel/mm/page_alloc.c~remove-zone_mem_map 2006-03-16 02:09:09.000000000 -0800 +++ devel-akpm/mm/page_alloc.c 2006-03-16 02:09:09.000000000 -0800 @@ -2043,7 +2043,6 @@ static __meminit void init_currently_emp zone_wait_table_init(zone, size); pgdat->nr_zones = zone_idx(zone) + 1; - zone->zone_mem_map = pfn_to_page(zone_start_pfn); zone->zone_start_pfn = zone_start_pfn; memmap_init(size, pgdat->node_id, zone_idx(zone), zone_start_pfn); @@ -2769,9 +2768,8 @@ struct page *pfn_to_page(unsigned long p } unsigned long page_to_pfn(struct page *page) { - struct zone *zone = page_zone(page); - return (page - zone->zone_mem_map) + zone->zone_start_pfn; - + 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) _