[linux-2.6-block.git] / include / linux / dm-kcopyd.h

/*
 * Copyright (C) 2001 - 2003 Sistina Software
 * Copyright (C) 2004 - 2008 Red Hat, Inc. All rights reserved.
 *
 * kcopyd provides a simple interface for copying an area of one
 * block-device to one or more other block-devices, either synchronous
 * or with an asynchronous completion notification.
 *
 * This file is released under the GPL.
 */

#ifndef _LINUX_DM_KCOPYD_H
#define _LINUX_DM_KCOPYD_H

#ifdef __KERNEL__

#include <linux/dm-io.h>

/* FIXME: make this configurable */
#define DM_KCOPYD_MAX_REGIONS 8

#define DM_KCOPYD_IGNORE_ERROR 1

/*
 * To use kcopyd you must first create a dm_kcopyd_client object.
 */
struct dm_kcopyd_client;
struct dm_kcopyd_client *dm_kcopyd_client_create(void);
void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc);

/*
 * Submit a copy job to kcopyd.  This is built on top of the
 * previous three fns.
 *
 * read_err is a boolean,
 * write_err is a bitset, with 1 bit for each destination region
 */
typedef void (*dm_kcopyd_notify_fn)(int read_err, unsigned long write_err,
				    void *context);

int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
		   unsigned num_dests, struct dm_io_region *dests,
		   unsigned flags, dm_kcopyd_notify_fn fn, void *context);

/*
 * Prepare a callback and submit it via the kcopyd thread.
 *
 * dm_kcopyd_prepare_callback allocates a callback structure and returns it.
 * It must not be called from interrupt context.
 * The returned value should be passed into dm_kcopyd_do_callback.
 *
 * dm_kcopyd_do_callback submits the callback.
 * It may be called from interrupt context.
 * The callback is issued from the kcopyd thread.
 */
void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc,
				 dm_kcopyd_notify_fn fn, void *context);
void dm_kcopyd_do_callback(void *job, int read_err, unsigned long write_err);

int dm_kcopyd_zero(struct dm_kcopyd_client *kc,
		   unsigned num_dests, struct dm_io_region *dests,
		   unsigned flags, dm_kcopyd_notify_fn fn, void *context);

#endif	/* __KERNEL__ */
#endif	/* _LINUX_DM_KCOPYD_H */
Commit	Line	Data
1da177e4	1	/*
eb69aca5 HM	2	* Copyright (C) 2001 - 2003 Sistina Software
eb69aca5 HM	3	* Copyright (C) 2004 - 2008 Red Hat, Inc. All rights reserved.
1da177e4	4	*
eb69aca5 HM	5	* kcopyd provides a simple interface for copying an area of one
	6	* block-device to one or more other block-devices, either synchronous
	7	* or with an asynchronous completion notification.
1da177e4	8	*
eb69aca5	9	* This file is released under the GPL.
1da177e4 LT	10	*/
1da177e4 LT	11
eb69aca5 HM	12	#ifndef _LINUX_DM_KCOPYD_H
	13	#define _LINUX_DM_KCOPYD_H
	14
	15	#ifdef __KERNEL__
1da177e4	16
a765e20e	17	#include <linux/dm-io.h>
1da177e4 LT	18
1da177e4 LT	19	/* FIXME: make this configurable */
eb69aca5	20	#define DM_KCOPYD_MAX_REGIONS 8
1da177e4	21
eb69aca5	22	#define DM_KCOPYD_IGNORE_ERROR 1
1da177e4 LT	23
1da177e4 LT	24	/*
eb69aca5	25	* To use kcopyd you must first create a dm_kcopyd_client object.
1da177e4	26	*/
eb69aca5	27	struct dm_kcopyd_client;
fa34ce73	28	struct dm_kcopyd_client *dm_kcopyd_client_create(void);
eb69aca5	29	void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc);
1da177e4 LT	30
	31	/*
	32	* Submit a copy job to kcopyd. This is built on top of the
	33	* previous three fns.
	34	*
	35	* read_err is a boolean,
	36	* write_err is a bitset, with 1 bit for each destination region
	37	*/
eb69aca5 HM	38	typedef void (*dm_kcopyd_notify_fn)(int read_err, unsigned long write_err,
eb69aca5 HM	39	void *context);
1da177e4	40
eb69aca5 HM	41	int dm_kcopyd_copy(struct dm_kcopyd_client kc, struct dm_io_region from,
	42	unsigned num_dests, struct dm_io_region *dests,
	43	unsigned flags, dm_kcopyd_notify_fn fn, void *context);
1da177e4	44
a6e50b40 MP	45	/*
	46	* Prepare a callback and submit it via the kcopyd thread.
	47	*
	48	* dm_kcopyd_prepare_callback allocates a callback structure and returns it.
	49	* It must not be called from interrupt context.
	50	* The returned value should be passed into dm_kcopyd_do_callback.
	51	*
	52	* dm_kcopyd_do_callback submits the callback.
	53	* It may be called from interrupt context.
	54	* The callback is issued from the kcopyd thread.
	55	*/
	56	void dm_kcopyd_prepare_callback(struct dm_kcopyd_client kc,
	57	dm_kcopyd_notify_fn fn, void *context);
	58	void dm_kcopyd_do_callback(void *job, int read_err, unsigned long write_err);
	59
7f069653 MP	60	int dm_kcopyd_zero(struct dm_kcopyd_client *kc,
	61	unsigned num_dests, struct dm_io_region *dests,
	62	unsigned flags, dm_kcopyd_notify_fn fn, void *context);
	63
eb69aca5 HM	64	#endif /* __KERNEL__ */
eb69aca5 HM	65	#endif /* _LINUX_DM_KCOPYD_H */