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