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; |
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 | |
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 |