[GitHub/mt8127/android_kernel_alcatel_ttab.git] / mm / mmzone.c

/*
 * linux/mm/mmzone.c
 *
 * management codes for pgdats, zones and page flags
 */


#include <linux/stddef.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/export.h>

struct pglist_data *first_online_pgdat(void)
{
	return NODE_DATA(first_online_node);
}
EXPORT_SYMBOL_GPL(first_online_pgdat);

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);
}
EXPORT_SYMBOL_GPL(next_online_pgdat);

/*
 * 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;
}
EXPORT_SYMBOL_GPL(next_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 */

void lruvec_init(struct lruvec *lruvec)
{
	enum lru_list lru;

	memset(lruvec, 0, sizeof(struct lruvec));

	for_each_lru(lru)
		INIT_LIST_HEAD(&lruvec->lists[lru]);
}

#if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_NID_NOT_IN_PAGE_FLAGS)
int page_nid_xchg_last(struct page *page, int nid)
{
	unsigned long old_flags, flags;
	int last_nid;

	do {
		old_flags = flags = page->flags;
		last_nid = page_nid_last(page);

		flags &= ~(LAST_NID_MASK << LAST_NID_PGSHIFT);
		flags |= (nid & LAST_NID_MASK) << LAST_NID_PGSHIFT;
	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));

	return last_nid;
}
#endif
Commit	Line	Data
95144c78 KH	1	/*
	2	* linux/mm/mmzone.c
	3	*
4468b8f1	4	* management codes for pgdats, zones and page flags
95144c78 KH	5	*/
	6
	7
95144c78	8	#include <linux/stddef.h>
eb33575c	9	#include <linux/mm.h>
95144c78	10	#include <linux/mmzone.h>
6fa3eb70	11	#include <linux/export.h>
95144c78 KH	12
	13	struct pglist_data *first_online_pgdat(void)
	14	{
	15	return NODE_DATA(first_online_node);
	16	}
6fa3eb70	17	EXPORT_SYMBOL_GPL(first_online_pgdat);
95144c78	18
95144c78 KH	19	struct pglist_data next_online_pgdat(struct pglist_data pgdat)
	20	{
	21	int nid = next_online_node(pgdat->node_id);
	22
	23	if (nid == MAX_NUMNODES)
	24	return NULL;
	25	return NODE_DATA(nid);
	26	}
6fa3eb70	27	EXPORT_SYMBOL_GPL(next_online_pgdat);
95144c78 KH	28
	29	/*
	30	* next_zone - helper magic for for_each_zone()
	31	*/
	32	struct zone next_zone(struct zone zone)
	33	{
	34	pg_data_t *pgdat = zone->zone_pgdat;
	35
	36	if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
	37	zone++;
	38	else {
	39	pgdat = next_online_pgdat(pgdat);
	40	if (pgdat)
	41	zone = pgdat->node_zones;
	42	else
	43	zone = NULL;
	44	}
	45	return zone;
	46	}
6fa3eb70	47	EXPORT_SYMBOL_GPL(next_zone);
95144c78	48
19770b32 MG	49	static inline int zref_in_nodemask(struct zoneref zref, nodemask_t nodes)
	50	{
	51	#ifdef CONFIG_NUMA
	52	return node_isset(zonelist_node_idx(zref), *nodes);
	53	#else
	54	return 1;
	55	#endif /* CONFIG_NUMA */
	56	}
	57
	58	/* Returns the next zone at or below highest_zoneidx in a zonelist */
	59	struct zoneref next_zones_zonelist(struct zoneref z,
	60	enum zone_type highest_zoneidx,
	61	nodemask_t *nodes,
	62	struct zone **zone)
	63	{
	64	/*
	65	* Find the next suitable zone to use for the allocation.
	66	* Only filter based on nodemask if it's set
	67	*/
	68	if (likely(nodes == NULL))
	69	while (zonelist_zone_idx(z) > highest_zoneidx)
	70	z++;
	71	else
	72	while (zonelist_zone_idx(z) > highest_zoneidx \|\|
	73	(z->zone && !zref_in_nodemask(z, nodes)))
	74	z++;
	75
5bead2a0	76	*zone = zonelist_zone(z);
19770b32 MG	77	return z;
19770b32 MG	78	}
eb33575c MG	79
	80	#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
	81	int memmap_valid_within(unsigned long pfn,
	82	struct page page, struct zone zone)
	83	{
	84	if (page_to_pfn(page) != pfn)
	85	return 0;
	86
	87	if (page_zone(page) != zone)
	88	return 0;
	89
	90	return 1;
	91	}
	92	#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
7f5e86c2	93
bea8c150	94	void lruvec_init(struct lruvec *lruvec)
7f5e86c2 KK	95	{
	96	enum lru_list lru;
	97
	98	memset(lruvec, 0, sizeof(struct lruvec));
	99
	100	for_each_lru(lru)
	101	INIT_LIST_HEAD(&lruvec->lists[lru]);
7f5e86c2	102	}
4468b8f1 MG	103
4468b8f1 MG	104	#if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_NID_NOT_IN_PAGE_FLAGS)
22b751c3	105	int page_nid_xchg_last(struct page *page, int nid)
4468b8f1 MG	106	{
	107	unsigned long old_flags, flags;
	108	int last_nid;
	109
	110	do {
	111	old_flags = flags = page->flags;
22b751c3	112	last_nid = page_nid_last(page);
4468b8f1 MG	113
	114	flags &= ~(LAST_NID_MASK << LAST_NID_PGSHIFT);
	115	flags \|= (nid & LAST_NID_MASK) << LAST_NID_PGSHIFT;
	116	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));
	117
	118	return last_nid;
	119	}
	120	#endif