[linux-block.git] / include / scsi / scsi_transport.h

/* 
 *  Transport specific attributes.
 *
 *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#ifndef SCSI_TRANSPORT_H
#define SCSI_TRANSPORT_H

#include <linux/transport_class.h>
#include <linux/blkdev.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>

struct scsi_transport_template {
	/* the attribute containers */
	struct transport_container host_attrs;
	struct transport_container target_attrs;
	struct transport_container device_attrs;

	/*
	 * If set, called from sysfs and legacy procfs rescanning code.
	 */
	int (*user_scan)(struct Scsi_Host *, uint, uint, uint);

	/* The size of the specific transport attribute structure (a
	 * space of this size will be left at the end of the
	 * scsi_* structure */
	int	device_size;
	int	device_private_offset;
	int	target_size;
	int	target_private_offset;
	int	host_size;
	/* no private offset for the host; there's an alternative mechanism */

	/*
	 * True if the transport wants to use a host-based work-queue
	 */
	unsigned int create_work_queue : 1;

	/*
	 * Allows a transport to override the default error handler.
	 */
	void (* eh_strategy_handler)(struct Scsi_Host *);

	/*
	 * This is an optional routine that allows the transport to become
	 * involved when a scsi io timer fires. The return value tells the
	 * timer routine how to finish the io timeout handling:
	 * EH_HANDLED:		I fixed the error, please complete the command
	 * EH_RESET_TIMER:	I need more time, reset the timer and
	 *			begin counting again
	 * EH_NOT_HANDLED	Begin normal error recovery
	 */
	enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);

	/*
	 * Used as callback for the completion of i_t_nexus request
	 * for target drivers.
	 */
	int (* it_nexus_response)(struct Scsi_Host *, u64, int);

	/*
	 * Used as callback for the completion of task management
	 * request for target drivers.
	 */
	int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int);
};

#define transport_class_to_shost(tc) \
	dev_to_shost((tc)->parent)


/* Private area maintenance. The driver requested allocations come
 * directly after the transport class allocations (if any).  The idea
 * is that you *must* call these only once.  The code assumes that the
 * initial values are the ones the transport specific code requires */
static inline void
scsi_transport_reserve_target(struct scsi_transport_template * t, int space)
{
	BUG_ON(t->target_private_offset != 0);
	t->target_private_offset = ALIGN(t->target_size, sizeof(void *));
	t->target_size = t->target_private_offset + space;
}
static inline void
scsi_transport_reserve_device(struct scsi_transport_template * t, int space)
{
	BUG_ON(t->device_private_offset != 0);
	t->device_private_offset = ALIGN(t->device_size, sizeof(void *));
	t->device_size = t->device_private_offset + space;
}
static inline void *
scsi_transport_target_data(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(&starget->dev);
	return (u8 *)starget->starget_data
		+ shost->transportt->target_private_offset;

}
static inline void *
scsi_transport_device_data(struct scsi_device *sdev)
{
	struct Scsi_Host *shost = sdev->host;
	return (u8 *)sdev->sdev_data
		+ shost->transportt->device_private_offset;
}

#endif /* SCSI_TRANSPORT_H */
Commit	Line	Data
	1	/*
	2	* Transport specific attributes.
	3	*
	4	* Copyright (c) 2003 Silicon Graphics, Inc. All rights reserved.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20	#ifndef SCSI_TRANSPORT_H
	21	#define SCSI_TRANSPORT_H
	22
	23	#include <linux/transport_class.h>
	24	#include <linux/blkdev.h>
	25	#include <scsi/scsi_host.h>
	26	#include <scsi/scsi_device.h>
	27
	28	struct scsi_transport_template {
	29	/* the attribute containers */
	30	struct transport_container host_attrs;
	31	struct transport_container target_attrs;
	32	struct transport_container device_attrs;
	33
	34	/*
	35	* If set, called from sysfs and legacy procfs rescanning code.
	36	*/
	37	int (user_scan)(struct Scsi_Host , uint, uint, uint);
	38
	39	/* The size of the specific transport attribute structure (a
	40	* space of this size will be left at the end of the
	41	* scsi_* structure */
	42	int device_size;
	43	int device_private_offset;
	44	int target_size;
	45	int target_private_offset;
	46	int host_size;
	47	/* no private offset for the host; there's an alternative mechanism */
	48
	49	/*
	50	* True if the transport wants to use a host-based work-queue
	51	*/
	52	unsigned int create_work_queue : 1;
	53
	54	/*
	55	* Allows a transport to override the default error handler.
	56	*/
	57	void (* eh_strategy_handler)(struct Scsi_Host *);
	58
	59	/*
	60	* This is an optional routine that allows the transport to become
	61	* involved when a scsi io timer fires. The return value tells the
	62	* timer routine how to finish the io timeout handling:
	63	* EH_HANDLED: I fixed the error, please complete the command
	64	* EH_RESET_TIMER: I need more time, reset the timer and
	65	* begin counting again
	66	* EH_NOT_HANDLED Begin normal error recovery
	67	*/
	68	enum blk_eh_timer_return (eh_timed_out)(struct scsi_cmnd );
	69
	70	/*
	71	* Used as callback for the completion of i_t_nexus request
	72	* for target drivers.
	73	*/
	74	int (* it_nexus_response)(struct Scsi_Host *, u64, int);
	75
	76	/*
	77	* Used as callback for the completion of task management
	78	* request for target drivers.
	79	*/
	80	int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int);
	81	};
	82
	83	#define transport_class_to_shost(tc) \
	84	dev_to_shost((tc)->parent)
	85
	86
	87	/* Private area maintenance. The driver requested allocations come
	88	* directly after the transport class allocations (if any). The idea
	89	* is that you must call these only once. The code assumes that the
	90	* initial values are the ones the transport specific code requires */
	91	static inline void
	92	scsi_transport_reserve_target(struct scsi_transport_template * t, int space)
	93	{
	94	BUG_ON(t->target_private_offset != 0);
	95	t->target_private_offset = ALIGN(t->target_size, sizeof(void *));
	96	t->target_size = t->target_private_offset + space;
	97	}
	98	static inline void
	99	scsi_transport_reserve_device(struct scsi_transport_template * t, int space)
	100	{
	101	BUG_ON(t->device_private_offset != 0);
	102	t->device_private_offset = ALIGN(t->device_size, sizeof(void *));
	103	t->device_size = t->device_private_offset + space;
	104	}
	105	static inline void *
	106	scsi_transport_target_data(struct scsi_target *starget)
	107	{
	108	struct Scsi_Host *shost = dev_to_shost(&starget->dev);
	109	return (u8 *)starget->starget_data
	110	+ shost->transportt->target_private_offset;
	111
	112	}
	113	static inline void *
	114	scsi_transport_device_data(struct scsi_device *sdev)
	115	{
	116	struct Scsi_Host *shost = sdev->host;
	117	return (u8 *)sdev->sdev_data
	118	+ shost->transportt->device_private_offset;
	119	}
	120
	121	#endif /* SCSI_TRANSPORT_H */