LXR linux/include/scsi/scsi

   1/*
   2 * Header file for SCSI device handler infrastruture.
   3 *
   4 * Modified version of patches posted by Mike Christie <michaelc@cs.wisc.edu>
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms of the GNU General Public License as published by the
   8 * Free Software Foundation; either version 2 of the License, or (at your
   9 * option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful, but
  12 * WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License along
  17 * with this program; if not, write to the Free Software Foundation, Inc.,
  18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19 *
  20 * Copyright IBM Corporation, 2007
  21 *      Authors:
  22 *               Chandra Seetharaman <sekharan@us.ibm.com>
  23 *               Mike Anderson <andmike@linux.vnet.ibm.com>
  24 */
  25
  26#include <scsi/scsi_device.h>
  27
  28enum {
  29        SCSI_DH_OK = 0,
  30        /*
  31         * device errors
  32         */
  33        SCSI_DH_DEV_FAILED,     /* generic device error */
  34        SCSI_DH_DEV_TEMP_BUSY,
  35        SCSI_DH_DEV_UNSUPP,     /* device handler not supported */
  36        SCSI_DH_DEVICE_MAX,     /* max device blkerr definition */
  37
  38        /*
  39         * transport errors
  40         */
  41        SCSI_DH_NOTCONN = SCSI_DH_DEVICE_MAX + 1,
  42        SCSI_DH_CONN_FAILURE,
  43        SCSI_DH_TRANSPORT_MAX,  /* max transport blkerr definition */
  44
  45        /*
  46         * driver and generic errors
  47         */
  48        SCSI_DH_IO = SCSI_DH_TRANSPORT_MAX + 1, /* generic error */
  49        SCSI_DH_INVALID_IO,
  50        SCSI_DH_RETRY,          /* retry the req, but not immediately */
  51        SCSI_DH_IMM_RETRY,      /* immediately retry the req */
  52        SCSI_DH_TIMED_OUT,
  53        SCSI_DH_RES_TEMP_UNAVAIL,
  54        SCSI_DH_DEV_OFFLINED,
  55        SCSI_DH_NOMEM,
  56        SCSI_DH_NOSYS,
  57        SCSI_DH_DRIVER_MAX,
  58};
  59
  60typedef void (*activate_complete)(void *, int);
  61struct scsi_device_handler {
  62        /* Used by the infrastructure */
  63        struct list_head list; /* list of scsi_device_handlers */
  64
  65        /* Filled by the hardware handler */
  66        struct module *module;
  67        const char *name;
  68        int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
  69        int (*attach)(struct scsi_device *);
  70        void (*detach)(struct scsi_device *);
  71        int (*activate)(struct scsi_device *, activate_complete, void *);
  72        int (*prep_fn)(struct scsi_device *, struct request *);
  73        int (*set_params)(struct scsi_device *, const char *);
  74        void (*rescan)(struct scsi_device *);
  75};
  76
  77#ifdef CONFIG_SCSI_DH
  78extern int scsi_dh_activate(struct request_queue *, activate_complete, void *);
  79extern int scsi_dh_attach(struct request_queue *, const char *);
  80extern const char *scsi_dh_attached_handler_name(struct request_queue *, gfp_t);
  81extern int scsi_dh_set_params(struct request_queue *, const char *);
  82#else
  83static inline int scsi_dh_activate(struct request_queue *req,
  84                                        activate_complete fn, void *data)
  85{
  86        fn(data, 0);
  87        return 0;
  88}
  89static inline int scsi_dh_attach(struct request_queue *req, const char *name)
  90{
  91        return SCSI_DH_NOSYS;
  92}
  93static inline const char *scsi_dh_attached_handler_name(struct request_queue *q,
  94                                                        gfp_t gfp)
  95{
  96        return NULL;
  97}
  98static inline int scsi_dh_set_params(struct request_queue *req, const char *params)
  99{
 100        return -SCSI_DH_NOSYS;
 101}
 102#endif
 103