[linux.git] / mm / mmzone.c

/*
 * 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 */
Commit	Line	Data
95144c78 KH	1	/*
	2	* linux/mm/mmzone.c
	3	*
	4	* management codes for pgdats and zones.
	5	*/
	6
	7
95144c78	8	#include <linux/stddef.h>
eb33575c	9	#include <linux/mm.h>
95144c78 KH	10	#include <linux/mmzone.h>
	11	#include <linux/module.h>
	12
	13	struct pglist_data *first_online_pgdat(void)
	14	{
	15	return NODE_DATA(first_online_node);
	16	}
	17
95144c78 KH	18	struct pglist_data next_online_pgdat(struct pglist_data pgdat)
	19	{
	20	int nid = next_online_node(pgdat->node_id);
	21
	22	if (nid == MAX_NUMNODES)
	23	return NULL;
	24	return NODE_DATA(nid);
	25	}
95144c78 KH	26
	27	/*
	28	* next_zone - helper magic for for_each_zone()
	29	*/
	30	struct zone next_zone(struct zone zone)
	31	{
	32	pg_data_t *pgdat = zone->zone_pgdat;
	33
	34	if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
	35	zone++;
	36	else {
	37	pgdat = next_online_pgdat(pgdat);
	38	if (pgdat)
	39	zone = pgdat->node_zones;
	40	else
	41	zone = NULL;
	42	}
	43	return zone;
	44	}
95144c78	45
19770b32 MG	46	static inline int zref_in_nodemask(struct zoneref zref, nodemask_t nodes)
	47	{
	48	#ifdef CONFIG_NUMA
	49	return node_isset(zonelist_node_idx(zref), *nodes);
	50	#else
	51	return 1;
	52	#endif /* CONFIG_NUMA */
	53	}
	54
	55	/* Returns the next zone at or below highest_zoneidx in a zonelist */
	56	struct zoneref next_zones_zonelist(struct zoneref z,
	57	enum zone_type highest_zoneidx,
	58	nodemask_t *nodes,
	59	struct zone **zone)
	60	{
	61	/*
	62	* Find the next suitable zone to use for the allocation.
	63	* Only filter based on nodemask if it's set
	64	*/
	65	if (likely(nodes == NULL))
	66	while (zonelist_zone_idx(z) > highest_zoneidx)
	67	z++;
	68	else
	69	while (zonelist_zone_idx(z) > highest_zoneidx \|\|
	70	(z->zone && !zref_in_nodemask(z, nodes)))
	71	z++;
	72
5bead2a0	73	*zone = zonelist_zone(z);
19770b32 MG	74	return z;
19770b32 MG	75	}
eb33575c MG	76
	77	#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
	78	int memmap_valid_within(unsigned long pfn,
	79	struct page page, struct zone zone)
	80	{
	81	if (page_to_pfn(page) != pfn)
	82	return 0;
	83
	84	if (page_zone(page) != zone)
	85	return 0;
	86
	87	return 1;
	88	}
	89	#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */