diff options
Diffstat (limited to 'mm/mmzone.c')
-rw-r--r-- | mm/mmzone.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/mm/mmzone.c b/mm/mmzone.c new file mode 100644 index 00000000..f5b7d176 --- /dev/null +++ b/mm/mmzone.c @@ -0,0 +1,89 @@ +/* + * linux/mm/mmzone.c + * + * management codes for pgdats and zones. + */ + + +#include <linux/stddef.h> +#include <linux/mm.h> +#include <linux/mmzone.h> +#include <linux/module.h> + +struct pglist_data *first_online_pgdat(void) +{ + return NODE_DATA(first_online_node); +} + +struct pglist_data *next_online_pgdat(struct pglist_data *pgdat) +{ + int nid = next_online_node(pgdat->node_id); + + if (nid == MAX_NUMNODES) + return NULL; + return NODE_DATA(nid); +} + +/* + * next_zone - helper magic for for_each_zone() + */ +struct zone *next_zone(struct zone *zone) +{ + pg_data_t *pgdat = zone->zone_pgdat; + + if (zone < pgdat->node_zones + MAX_NR_ZONES - 1) + zone++; + else { + pgdat = next_online_pgdat(pgdat); + if (pgdat) + zone = pgdat->node_zones; + else + zone = NULL; + } + return zone; +} + +static inline int zref_in_nodemask(struct zoneref *zref, nodemask_t *nodes) +{ +#ifdef CONFIG_NUMA + return node_isset(zonelist_node_idx(zref), *nodes); +#else + return 1; +#endif /* CONFIG_NUMA */ +} + +/* Returns the next zone at or below highest_zoneidx in a zonelist */ +struct zoneref *next_zones_zonelist(struct zoneref *z, + enum zone_type highest_zoneidx, + nodemask_t *nodes, + struct zone **zone) +{ + /* + * Find the next suitable zone to use for the allocation. + * Only filter based on nodemask if it's set + */ + if (likely(nodes == NULL)) + while (zonelist_zone_idx(z) > highest_zoneidx) + z++; + else + while (zonelist_zone_idx(z) > highest_zoneidx || + (z->zone && !zref_in_nodemask(z, nodes))) + z++; + + *zone = zonelist_zone(z); + return z; +} + +#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL +int memmap_valid_within(unsigned long pfn, + struct page *page, struct zone *zone) +{ + if (page_to_pfn(page) != pfn) + return 0; + + if (page_zone(page) != zone) + return 0; + + return 1; +} +#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */ |