diff options
| -rw-r--r-- | include/linux/mm.h | 7 | ||||
| -rw-r--r-- | include/linux/mmzone.h | 66 | ||||
| -rw-r--r-- | mm/page_alloc.c | 24 |
3 files changed, 69 insertions, 28 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 45678b036955..2db4229a0066 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -470,7 +470,7 @@ void split_page(struct page *page, unsigned int order); #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) #define ZONETABLE_MASK ((1UL << ZONETABLE_SHIFT) - 1) -static inline unsigned long page_zonenum(struct page *page) +static inline enum zone_type page_zonenum(struct page *page) { return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; } @@ -499,11 +499,12 @@ static inline unsigned long page_to_section(struct page *page) return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; } -static inline void set_page_zone(struct page *page, unsigned long zone) +static inline void set_page_zone(struct page *page, enum zone_type zone) { page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; } + static inline void set_page_node(struct page *page, unsigned long node) { page->flags &= ~(NODES_MASK << NODES_PGSHIFT); @@ -515,7 +516,7 @@ static inline void set_page_section(struct page *page, unsigned long section) page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; } -static inline void set_page_links(struct page *page, unsigned long zone, +static inline void set_page_links(struct page *page, enum zone_type zone, unsigned long node, unsigned long pfn) { set_page_zone(page, zone); diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index f45163c528e8..03a5a6eb0ffa 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -88,14 +88,53 @@ struct per_cpu_pageset { #define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)]) #endif -#define ZONE_DMA 0 -#define ZONE_DMA32 1 -#define ZONE_NORMAL 2 -#define ZONE_HIGHMEM 3 +enum zone_type { + /* + * ZONE_DMA is used when there are devices that are not able + * to do DMA to all of addressable memory (ZONE_NORMAL). Then we + * carve out the portion of memory that is needed for these devices. + * The range is arch specific. + * + * Some examples + * + * Architecture Limit + * --------------------------- + * parisc, ia64, sparc <4G + * s390 <2G + * arm26 <48M + * arm Various + * alpha Unlimited or 0-16MB. + * + * i386, x86_64 and multiple other arches + * <16M. + */ + ZONE_DMA, + /* + * x86_64 needs two ZONE_DMAs because it supports devices that are + * only able to do DMA to the lower 16M but also 32 bit devices that + * can only do DMA areas below 4G. + */ + ZONE_DMA32, + /* + * Normal addressable memory is in ZONE_NORMAL. DMA operations can be + * performed on pages in ZONE_NORMAL if the DMA devices support + * transfers to all addressable memory. + */ + ZONE_NORMAL, + /* + * A memory area that is only addressable by the kernel through + * mapping portions into its own address space. This is for example + * used by i386 to allow the kernel to address the memory beyond + * 900MB. The kernel will set up special mappings (page + * table entries on i386) for each page that the kernel needs to + * access. + */ + ZONE_HIGHMEM, -#define MAX_NR_ZONES 4 /* Sync this with ZONES_SHIFT */ -#define ZONES_SHIFT 2 /* ceil(log2(MAX_NR_ZONES)) */ + MAX_NR_ZONES +}; +#define ZONES_SHIFT 2 /* ceil(log2(MAX_NR_ZONES)) */ /* * When a memory allocation must conform to specific limitations (such @@ -126,16 +165,6 @@ struct per_cpu_pageset { /* #define GFP_ZONETYPES (GFP_ZONEMASK + 1) */ /* Non-loner */ #define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */ -/* - * On machines where it is needed (eg PCs) we divide physical memory - * into multiple physical zones. On a 32bit PC we have 4 zones: - * - * ZONE_DMA < 16 MB ISA DMA capable memory - * ZONE_DMA32 0 MB Empty - * ZONE_NORMAL 16-896 MB direct mapped by the kernel - * ZONE_HIGHMEM > 896 MB only page cache and user processes - */ - struct zone { /* Fields commonly accessed by the page allocator */ unsigned long free_pages; @@ -266,7 +295,6 @@ struct zone { char *name; } ____cacheline_internodealigned_in_smp; - /* * The "priority" of VM scanning is how much of the queues we will scan in one * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the @@ -373,12 +401,12 @@ static inline int populated_zone(struct zone *zone) return (!!zone->present_pages); } -static inline int is_highmem_idx(int idx) +static inline int is_highmem_idx(enum zone_type idx) { return (idx == ZONE_HIGHMEM); } -static inline int is_normal_idx(int idx) +static inline int is_normal_idx(enum zone_type idx) { return (idx == ZONE_NORMAL); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 13c102b95c57..2410a3cb1c53 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -68,7 +68,11 @@ static void __free_pages_ok(struct page *page, unsigned int order); * TBD: should special case ZONE_DMA32 machines here - in those we normally * don't need any ZONE_NORMAL reservation */ -int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 256, 256, 32 }; +int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { + 256, + 256, + 32 +}; EXPORT_SYMBOL(totalram_pages); @@ -79,7 +83,13 @@ EXPORT_SYMBOL(totalram_pages); struct zone *zone_table[1 << ZONETABLE_SHIFT] __read_mostly; EXPORT_SYMBOL(zone_table); -static char *zone_names[MAX_NR_ZONES] = { "DMA", "DMA32", "Normal", "HighMem" }; +static char *zone_names[MAX_NR_ZONES] = { + "DMA", + "DMA32", + "Normal", + "HighMem" +}; + int min_free_kbytes = 1024; unsigned long __meminitdata nr_kernel_pages; @@ -1487,7 +1497,9 @@ static void __meminit build_zonelists(pg_data_t *pgdat) static void __meminit build_zonelists(pg_data_t *pgdat) { - int i, j, k, node, local_node; + int i, node, local_node; + enum zone_type k; + enum zone_type j; local_node = pgdat->node_id; for (i = 0; i < GFP_ZONETYPES; i++) { @@ -1675,8 +1687,8 @@ void zone_init_free_lists(struct pglist_data *pgdat, struct zone *zone, } #define ZONETABLE_INDEX(x, zone_nr) ((x << ZONES_SHIFT) | zone_nr) -void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn, - unsigned long size) +void zonetable_add(struct zone *zone, int nid, enum zone_type zid, + unsigned long pfn, unsigned long size) { unsigned long snum = pfn_to_section_nr(pfn); unsigned long end = pfn_to_section_nr(pfn + size); @@ -1960,7 +1972,7 @@ __meminit int init_currently_empty_zone(struct zone *zone, static void __meminit free_area_init_core(struct pglist_data *pgdat, unsigned long *zones_size, unsigned long *zholes_size) { - unsigned long j; + enum zone_type j; int nid = pgdat->node_id; unsigned long zone_start_pfn = pgdat->node_start_pfn; int ret; |