forked from mirrors/linux
		
	 1da177e4c3
			
		
	
	
		1da177e4c3
		
	
	
	
	
		
			
			Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
		
			
				
	
	
		
			130 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2001 Sistina Software (UK) Limited.
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|  * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
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|  *
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|  * This file is released under the LGPL.
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|  */
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| 
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| #ifndef _LINUX_DEVICE_MAPPER_H
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| #define _LINUX_DEVICE_MAPPER_H
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| 
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| struct dm_target;
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| struct dm_table;
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| struct dm_dev;
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| 
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| typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
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| 
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| union map_info {
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| 	void *ptr;
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| 	unsigned long long ll;
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| };
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| 
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| /*
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|  * In the constructor the target parameter will already have the
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|  * table, type, begin and len fields filled in.
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|  */
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| typedef int (*dm_ctr_fn) (struct dm_target *target,
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| 			  unsigned int argc, char **argv);
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| 
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| /*
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|  * The destructor doesn't need to free the dm_target, just
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|  * anything hidden ti->private.
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|  */
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| typedef void (*dm_dtr_fn) (struct dm_target *ti);
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| 
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| /*
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|  * The map function must return:
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|  * < 0: error
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|  * = 0: The target will handle the io by resubmitting it later
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|  * > 0: simple remap complete
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|  */
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| typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio,
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| 			  union map_info *map_context);
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| 
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| /*
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|  * Returns:
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|  * < 0 : error (currently ignored)
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|  * 0   : ended successfully
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|  * 1   : for some reason the io has still not completed (eg,
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|  *       multipath target might want to requeue a failed io).
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|  */
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| typedef int (*dm_endio_fn) (struct dm_target *ti,
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| 			    struct bio *bio, int error,
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| 			    union map_info *map_context);
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| 
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| typedef void (*dm_presuspend_fn) (struct dm_target *ti);
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| typedef void (*dm_postsuspend_fn) (struct dm_target *ti);
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| typedef void (*dm_resume_fn) (struct dm_target *ti);
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| 
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| typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
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| 			     char *result, unsigned int maxlen);
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| 
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| typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv);
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| 
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| void dm_error(const char *message);
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| 
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| /*
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|  * Constructors should call these functions to ensure destination devices
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|  * are opened/closed correctly.
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|  * FIXME: too many arguments.
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|  */
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| int dm_get_device(struct dm_target *ti, const char *path, sector_t start,
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| 		  sector_t len, int mode, struct dm_dev **result);
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| void dm_put_device(struct dm_target *ti, struct dm_dev *d);
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| 
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| /*
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|  * Information about a target type
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|  */
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| struct target_type {
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| 	const char *name;
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| 	struct module *module;
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|         unsigned version[3];
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| 	dm_ctr_fn ctr;
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| 	dm_dtr_fn dtr;
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| 	dm_map_fn map;
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| 	dm_endio_fn end_io;
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| 	dm_presuspend_fn presuspend;
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| 	dm_postsuspend_fn postsuspend;
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| 	dm_resume_fn resume;
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| 	dm_status_fn status;
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| 	dm_message_fn message;
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| };
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| 
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| struct io_restrictions {
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| 	unsigned short		max_sectors;
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| 	unsigned short		max_phys_segments;
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| 	unsigned short		max_hw_segments;
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| 	unsigned short		hardsect_size;
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| 	unsigned int		max_segment_size;
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| 	unsigned long		seg_boundary_mask;
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| };
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| 
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| struct dm_target {
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| 	struct dm_table *table;
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| 	struct target_type *type;
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| 
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| 	/* target limits */
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| 	sector_t begin;
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| 	sector_t len;
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| 
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| 	/* FIXME: turn this into a mask, and merge with io_restrictions */
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| 	/* Always a power of 2 */
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| 	sector_t split_io;
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| 
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| 	/*
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| 	 * These are automatically filled in by
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| 	 * dm_table_get_device.
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| 	 */
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| 	struct io_restrictions limits;
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| 
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| 	/* target specific data */
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| 	void *private;
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| 
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| 	/* Used to provide an error string from the ctr */
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| 	char *error;
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| };
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| 
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| int dm_register_target(struct target_type *t);
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| int dm_unregister_target(struct target_type *t);
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| 
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| #endif				/* _LINUX_DEVICE_MAPPER_H */
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