Commit | Line | Data |
---|---|---|
b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
af8d417a DS |
2 | /* |
3 | * zpool memory storage api | |
4 | * | |
5 | * Copyright (C) 2014 Dan Streetman | |
6 | * | |
7 | * This is a common frontend for the zbud and zsmalloc memory | |
8 | * storage pool implementations. Typically, this is used to | |
9 | * store compressed memory. | |
10 | */ | |
11 | ||
12 | #ifndef _ZPOOL_H_ | |
13 | #define _ZPOOL_H_ | |
14 | ||
15 | struct zpool; | |
16 | ||
17 | struct zpool_ops { | |
18 | int (*evict)(struct zpool *pool, unsigned long handle); | |
19 | }; | |
20 | ||
21 | /* | |
22 | * Control how a handle is mapped. It will be ignored if the | |
23 | * implementation does not support it. Its use is optional. | |
24 | * Note that this does not refer to memory protection, it | |
25 | * refers to how the memory will be copied in/out if copying | |
26 | * is necessary during mapping; read-write is the safest as | |
27 | * it copies the existing memory in on map, and copies the | |
28 | * changed memory back out on unmap. Write-only does not copy | |
29 | * in the memory and should only be used for initialization. | |
30 | * If in doubt, use ZPOOL_MM_DEFAULT which is read-write. | |
31 | */ | |
32 | enum zpool_mapmode { | |
33 | ZPOOL_MM_RW, /* normal read-write mapping */ | |
34 | ZPOOL_MM_RO, /* read-only (no copy-out at unmap time) */ | |
35 | ZPOOL_MM_WO, /* write-only (no copy-in at map time) */ | |
36 | ||
37 | ZPOOL_MM_DEFAULT = ZPOOL_MM_RW | |
38 | }; | |
39 | ||
3f0e1312 DS |
40 | bool zpool_has_pool(char *type); |
41 | ||
6f3526d6 | 42 | struct zpool *zpool_create_pool(const char *type, const char *name, |
78672779 | 43 | gfp_t gfp, const struct zpool_ops *ops); |
af8d417a | 44 | |
69e18f4d | 45 | const char *zpool_get_type(struct zpool *pool); |
af8d417a DS |
46 | |
47 | void zpool_destroy_pool(struct zpool *pool); | |
48 | ||
49 | int zpool_malloc(struct zpool *pool, size_t size, gfp_t gfp, | |
50 | unsigned long *handle); | |
51 | ||
52 | void zpool_free(struct zpool *pool, unsigned long handle); | |
53 | ||
54 | int zpool_shrink(struct zpool *pool, unsigned int pages, | |
55 | unsigned int *reclaimed); | |
56 | ||
57 | void *zpool_map_handle(struct zpool *pool, unsigned long handle, | |
58 | enum zpool_mapmode mm); | |
59 | ||
60 | void zpool_unmap_handle(struct zpool *pool, unsigned long handle); | |
61 | ||
62 | u64 zpool_get_total_size(struct zpool *pool); | |
63 | ||
64 | ||
65 | /** | |
66 | * struct zpool_driver - driver implementation for zpool | |
67 | * @type: name of the driver. | |
68 | * @list: entry in the list of zpool drivers. | |
69 | * @create: create a new pool. | |
70 | * @destroy: destroy a pool. | |
71 | * @malloc: allocate mem from a pool. | |
72 | * @free: free mem from a pool. | |
73 | * @shrink: shrink the pool. | |
74 | * @map: map a handle. | |
75 | * @unmap: unmap a handle. | |
76 | * @total_size: get total size of a pool. | |
77 | * | |
78 | * This is created by a zpool implementation and registered | |
79 | * with zpool. | |
80 | */ | |
81 | struct zpool_driver { | |
82 | char *type; | |
83 | struct module *owner; | |
84 | atomic_t refcount; | |
85 | struct list_head list; | |
86 | ||
6f3526d6 SS |
87 | void *(*create)(const char *name, |
88 | gfp_t gfp, | |
89 | const struct zpool_ops *ops, | |
479305fd | 90 | struct zpool *zpool); |
af8d417a DS |
91 | void (*destroy)(void *pool); |
92 | ||
93 | int (*malloc)(void *pool, size_t size, gfp_t gfp, | |
94 | unsigned long *handle); | |
95 | void (*free)(void *pool, unsigned long handle); | |
96 | ||
97 | int (*shrink)(void *pool, unsigned int pages, | |
98 | unsigned int *reclaimed); | |
99 | ||
100 | void *(*map)(void *pool, unsigned long handle, | |
101 | enum zpool_mapmode mm); | |
102 | void (*unmap)(void *pool, unsigned long handle); | |
103 | ||
104 | u64 (*total_size)(void *pool); | |
105 | }; | |
106 | ||
107 | void zpool_register_driver(struct zpool_driver *driver); | |
108 | ||
109 | int zpool_unregister_driver(struct zpool_driver *driver); | |
110 | ||
9c3760eb YZ |
111 | bool zpool_evictable(struct zpool *pool); |
112 | ||
af8d417a | 113 | #endif |