[linux-2.6-block.git] / drivers / md / dm-hw-handler.h

/*
 * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
 *
 * This file is released under the GPL.
 *
 * Multipath hardware handler registration.
 */

#ifndef	DM_HW_HANDLER_H
#define	DM_HW_HANDLER_H

#include <linux/device-mapper.h>

#include "dm-mpath.h"

struct hw_handler_type;
struct hw_handler {
	struct hw_handler_type *type;
	struct mapped_device *md;
	void *context;
};

/*
 * Constructs a hardware handler object, takes custom arguments
 */
/* Information about a hardware handler type */
struct hw_handler_type {
	char *name;
	struct module *module;

	int (*create) (struct hw_handler *handler, unsigned int argc,
		       char **argv);
	void (*destroy) (struct hw_handler *hwh);

	void (*pg_init) (struct hw_handler *hwh, unsigned bypassed,
			 struct dm_path *path);
	unsigned (*error) (struct hw_handler *hwh, struct bio *bio);
	int (*status) (struct hw_handler *hwh, status_type_t type,
		       char *result, unsigned int maxlen);
};

/* Register a hardware handler */
int dm_register_hw_handler(struct hw_handler_type *type);

/* Unregister a hardware handler */
int dm_unregister_hw_handler(struct hw_handler_type *type);

/* Returns a registered hardware handler type */
struct hw_handler_type *dm_get_hw_handler(const char *name);

/* Releases a hardware handler  */
void dm_put_hw_handler(struct hw_handler_type *hwht);

/* Default err function */
unsigned dm_scsi_err_handler(struct hw_handler *hwh, struct bio *bio);

/* Error flags for err and dm_pg_init_complete */
#define MP_FAIL_PATH 1
#define MP_BYPASS_PG 2
#define MP_ERROR_IO  4	/* Don't retry this I/O */
#define MP_RETRY 8

#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) 2004 Red Hat, Inc. All rights reserved.
	3	*
	4	* This file is released under the GPL.
	5	*
	6	* Multipath hardware handler registration.
	7	*/
	8
	9	#ifndef DM_HW_HANDLER_H
	10	#define DM_HW_HANDLER_H
	11
	12	#include <linux/device-mapper.h>
	13
	14	#include "dm-mpath.h"
	15
	16	struct hw_handler_type;
	17	struct hw_handler {
	18	struct hw_handler_type *type;
79eb885c	19	struct mapped_device *md;
1da177e4 LT	20	void *context;
	21	};
	22
	23	/*
	24	* Constructs a hardware handler object, takes custom arguments
	25	*/
	26	/* Information about a hardware handler type */
	27	struct hw_handler_type {
	28	char *name;
	29	struct module *module;
	30
	31	int (create) (struct hw_handler handler, unsigned int argc,
	32	char **argv);
	33	void (destroy) (struct hw_handler hwh);
	34
	35	void (pg_init) (struct hw_handler hwh, unsigned bypassed,
c922d5f7	36	struct dm_path *path);
1da177e4 LT	37	unsigned (error) (struct hw_handler hwh, struct bio *bio);
	38	int (status) (struct hw_handler hwh, status_type_t type,
	39	char *result, unsigned int maxlen);
	40	};
	41
	42	/* Register a hardware handler */
	43	int dm_register_hw_handler(struct hw_handler_type *type);
	44
	45	/* Unregister a hardware handler */
	46	int dm_unregister_hw_handler(struct hw_handler_type *type);
	47
	48	/* Returns a registered hardware handler type */
	49	struct hw_handler_type dm_get_hw_handler(const char name);
	50
	51	/* Releases a hardware handler */
	52	void dm_put_hw_handler(struct hw_handler_type *hwht);
	53
	54	/* Default err function */
	55	unsigned dm_scsi_err_handler(struct hw_handler hwh, struct bio bio);
	56
	57	/* Error flags for err and dm_pg_init_complete */
	58	#define MP_FAIL_PATH 1
	59	#define MP_BYPASS_PG 2
	60	#define MP_ERROR_IO 4 /* Don't retry this I/O */
c9e45581	61	#define MP_RETRY 8
1da177e4 LT	62
1da177e4 LT	63	#endif