root/include/scsi/scsi_dh.h

DEFINITIONS

1. scsi_dh_activate
2. scsi_dh_handler_exist
3. scsi_dh_attach
4. scsi_dh_detach
5. scsi_dh_attached_handler_name
6. scsi_dh_set_params

/*
 * Header file for SCSI device handler infrastruture.
 *
 * Modified version of patches posted by Mike Christie <michaelc@cs.wisc.edu>
 *
 * 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.
 *
 * Copyright IBM Corporation, 2007
 *      Authors:
 *               Chandra Seetharaman <sekharan@us.ibm.com>
 *               Mike Anderson <andmike@linux.vnet.ibm.com>
 */

#include <scsi/scsi_device.h>

enum {
        SCSI_DH_OK = 0,
        /*
         * device errors
         */
        SCSI_DH_DEV_FAILED,     /* generic device error */
        SCSI_DH_DEV_TEMP_BUSY,
        SCSI_DH_DEV_UNSUPP,     /* device handler not supported */
        SCSI_DH_DEVICE_MAX,     /* max device blkerr definition */

        /*
         * transport errors
         */
        SCSI_DH_NOTCONN = SCSI_DH_DEVICE_MAX + 1,
        SCSI_DH_CONN_FAILURE,
        SCSI_DH_TRANSPORT_MAX,  /* max transport blkerr definition */

        /*
         * driver and generic errors
         */
        SCSI_DH_IO = SCSI_DH_TRANSPORT_MAX + 1, /* generic error */
        SCSI_DH_INVALID_IO,
        SCSI_DH_RETRY,          /* retry the req, but not immediately */
        SCSI_DH_IMM_RETRY,      /* immediately retry the req */
        SCSI_DH_TIMED_OUT,
        SCSI_DH_RES_TEMP_UNAVAIL,
        SCSI_DH_DEV_OFFLINED,
        SCSI_DH_NOSYS,
        SCSI_DH_DRIVER_MAX,
};
#if defined(CONFIG_SCSI_DH) || defined(CONFIG_SCSI_DH_MODULE)
extern int scsi_dh_activate(struct request_queue *, activate_complete, void *);
extern int scsi_dh_handler_exist(const char *);
extern int scsi_dh_attach(struct request_queue *, const char *);
extern void scsi_dh_detach(struct request_queue *);
extern const char *scsi_dh_attached_handler_name(struct request_queue *, gfp_t);
extern int scsi_dh_set_params(struct request_queue *, const char *);
#else
static inline int scsi_dh_activate(struct request_queue *req,
                                        activate_complete fn, void *data)
{
        fn(data, 0);
        return 0;
}
static inline int scsi_dh_handler_exist(const char *name)
{
        return 0;
}
static inline int scsi_dh_attach(struct request_queue *req, const char *name)
{
        return SCSI_DH_NOSYS;
}
static inline void scsi_dh_detach(struct request_queue *q)
{
        return;
}
static inline const char *scsi_dh_attached_handler_name(struct request_queue *q,
                                                        gfp_t gfp)
{
        return NULL;
}
static inline int scsi_dh_set_params(struct request_queue *req, const char *params)
{
        return -SCSI_DH_NOSYS;
}
#endif