114 lines
3 KiB
C
114 lines
3 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
|
/*
|
||
|
|
* zpool memory storage api
|
||
|
|
*
|
||
|
|
* Copyright (C) 2014 Dan Streetman
|
||
|
|
*
|
||
|
|
* This is a common frontend for the zbud and zsmalloc memory
|
||
|
|
* storage pool implementations. Typically, this is used to
|
||
|
|
* store compressed memory.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef _ZPOOL_H_
|
||
|
|
#define _ZPOOL_H_
|
||
|
|
|
||
|
|
struct zpool;
|
||
|
|
|
||
|
|
struct zpool_ops {
|
||
|
|
int (*evict)(struct zpool *pool, unsigned long handle);
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Control how a handle is mapped. It will be ignored if the
|
||
|
|
* implementation does not support it. Its use is optional.
|
||
|
|
* Note that this does not refer to memory protection, it
|
||
|
|
* refers to how the memory will be copied in/out if copying
|
||
|
|
* is necessary during mapping; read-write is the safest as
|
||
|
|
* it copies the existing memory in on map, and copies the
|
||
|
|
* changed memory back out on unmap. Write-only does not copy
|
||
|
|
* in the memory and should only be used for initialization.
|
||
|
|
* If in doubt, use ZPOOL_MM_DEFAULT which is read-write.
|
||
|
|
*/
|
||
|
|
enum zpool_mapmode {
|
||
|
|
ZPOOL_MM_RW, /* normal read-write mapping */
|
||
|
|
ZPOOL_MM_RO, /* read-only (no copy-out at unmap time) */
|
||
|
|
ZPOOL_MM_WO, /* write-only (no copy-in at map time) */
|
||
|
|
|
||
|
|
ZPOOL_MM_DEFAULT = ZPOOL_MM_RW
|
||
|
|
};
|
||
|
|
|
||
|
|
bool zpool_has_pool(char *type);
|
||
|
|
|
||
|
|
struct zpool *zpool_create_pool(const char *type, const char *name,
|
||
|
|
gfp_t gfp, const struct zpool_ops *ops);
|
||
|
|
|
||
|
|
const char *zpool_get_type(struct zpool *pool);
|
||
|
|
|
||
|
|
void zpool_destroy_pool(struct zpool *pool);
|
||
|
|
|
||
|
|
int zpool_malloc(struct zpool *pool, size_t size, gfp_t gfp,
|
||
|
|
unsigned long *handle);
|
||
|
|
|
||
|
|
void zpool_free(struct zpool *pool, unsigned long handle);
|
||
|
|
|
||
|
|
int zpool_shrink(struct zpool *pool, unsigned int pages,
|
||
|
|
unsigned int *reclaimed);
|
||
|
|
|
||
|
|
void *zpool_map_handle(struct zpool *pool, unsigned long handle,
|
||
|
|
enum zpool_mapmode mm);
|
||
|
|
|
||
|
|
void zpool_unmap_handle(struct zpool *pool, unsigned long handle);
|
||
|
|
|
||
|
|
u64 zpool_get_total_size(struct zpool *pool);
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct zpool_driver - driver implementation for zpool
|
||
|
|
* @type: name of the driver.
|
||
|
|
* @list: entry in the list of zpool drivers.
|
||
|
|
* @create: create a new pool.
|
||
|
|
* @destroy: destroy a pool.
|
||
|
|
* @malloc: allocate mem from a pool.
|
||
|
|
* @free: free mem from a pool.
|
||
|
|
* @shrink: shrink the pool.
|
||
|
|
* @map: map a handle.
|
||
|
|
* @unmap: unmap a handle.
|
||
|
|
* @total_size: get total size of a pool.
|
||
|
|
*
|
||
|
|
* This is created by a zpool implementation and registered
|
||
|
|
* with zpool.
|
||
|
|
*/
|
||
|
|
struct zpool_driver {
|
||
|
|
char *type;
|
||
|
|
struct module *owner;
|
||
|
|
atomic_t refcount;
|
||
|
|
struct list_head list;
|
||
|
|
|
||
|
|
void *(*create)(const char *name,
|
||
|
|
gfp_t gfp,
|
||
|
|
const struct zpool_ops *ops,
|
||
|
|
struct zpool *zpool);
|
||
|
|
void (*destroy)(void *pool);
|
||
|
|
|
||
|
|
int (*malloc)(void *pool, size_t size, gfp_t gfp,
|
||
|
|
unsigned long *handle);
|
||
|
|
void (*free)(void *pool, unsigned long handle);
|
||
|
|
|
||
|
|
int (*shrink)(void *pool, unsigned int pages,
|
||
|
|
unsigned int *reclaimed);
|
||
|
|
|
||
|
|
void *(*map)(void *pool, unsigned long handle,
|
||
|
|
enum zpool_mapmode mm);
|
||
|
|
void (*unmap)(void *pool, unsigned long handle);
|
||
|
|
|
||
|
|
u64 (*total_size)(void *pool);
|
||
|
|
};
|
||
|
|
|
||
|
|
void zpool_register_driver(struct zpool_driver *driver);
|
||
|
|
|
||
|
|
int zpool_unregister_driver(struct zpool_driver *driver);
|
||
|
|
|
||
|
|
bool zpool_evictable(struct zpool *pool);
|
||
|
|
|
||
|
|
#endif
|