LXR linux/drivers/md/dm.h

   1/*
   2 * Internal header file for device mapper
   3 *
   4 * Copyright (C) 2001, 2002 Sistina Software
   5 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
   6 *
   7 * This file is released under the LGPL.
   8 */
   9
  10#ifndef DM_INTERNAL_H
  11#define DM_INTERNAL_H
  12
  13#include <linux/fs.h>
  14#include <linux/device-mapper.h>
  15#include <linux/list.h>
  16#include <linux/blkdev.h>
  17#include <linux/hdreg.h>
  18
  19/*
  20 * Suspend feature flags
  21 */
  22#define DM_SUSPEND_LOCKFS_FLAG          (1 << 0)
  23#define DM_SUSPEND_NOFLUSH_FLAG         (1 << 1)
  24
  25/*
  26 * Status feature flags
  27 */
  28#define DM_STATUS_NOFLUSH_FLAG          (1 << 0)
  29
  30/*
  31 * Type of table and mapped_device's mempool
  32 */
  33#define DM_TYPE_NONE            0
  34#define DM_TYPE_BIO_BASED       1
  35#define DM_TYPE_REQUEST_BASED   2
  36
  37/*
  38 * List of devices that a metadevice uses and should open/close.
  39 */
  40struct dm_dev_internal {
  41        struct list_head list;
  42        atomic_t count;
  43        struct dm_dev dm_dev;
  44};
  45
  46struct dm_table;
  47struct dm_md_mempools;
  48
  49/*-----------------------------------------------------------------
  50 * Internal table functions.
  51 *---------------------------------------------------------------*/
  52void dm_table_destroy(struct dm_table *t);
  53void dm_table_event_callback(struct dm_table *t,
  54                             void (*fn)(void *), void *context);
  55struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
  56struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
  57bool dm_table_has_no_data_devices(struct dm_table *table);
  58int dm_calculate_queue_limits(struct dm_table *table,
  59                              struct queue_limits *limits);
  60void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
  61                               struct queue_limits *limits);
  62struct list_head *dm_table_get_devices(struct dm_table *t);
  63void dm_table_presuspend_targets(struct dm_table *t);
  64void dm_table_postsuspend_targets(struct dm_table *t);
  65int dm_table_resume_targets(struct dm_table *t);
  66int dm_table_any_congested(struct dm_table *t, int bdi_bits);
  67int dm_table_any_busy_target(struct dm_table *t);
  68unsigned dm_table_get_type(struct dm_table *t);
  69struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
  70bool dm_table_request_based(struct dm_table *t);
  71bool dm_table_supports_discards(struct dm_table *t);
  72int dm_table_alloc_md_mempools(struct dm_table *t);
  73void dm_table_free_md_mempools(struct dm_table *t);
  74struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
  75
  76int dm_queue_merge_is_compulsory(struct request_queue *q);
  77
  78void dm_lock_md_type(struct mapped_device *md);
  79void dm_unlock_md_type(struct mapped_device *md);
  80void dm_set_md_type(struct mapped_device *md, unsigned type);
  81unsigned dm_get_md_type(struct mapped_device *md);
  82struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
  83
  84int dm_setup_md_queue(struct mapped_device *md);
  85
  86/*
  87 * To check the return value from dm_table_find_target().
  88 */
  89#define dm_target_is_valid(t) ((t)->table)
  90
  91/*
  92 * To check whether the target type is request-based or not (bio-based).
  93 */
  94#define dm_target_request_based(t) ((t)->type->map_rq != NULL)
  95
  96/*-----------------------------------------------------------------
  97 * A registry of target types.
  98 *---------------------------------------------------------------*/
  99int dm_target_init(void);
 100void dm_target_exit(void);
 101struct target_type *dm_get_target_type(const char *name);
 102void dm_put_target_type(struct target_type *tt);
 103int dm_target_iterate(void (*iter_func)(struct target_type *tt,
 104                                        void *param), void *param);
 105
 106int dm_split_args(int *argc, char ***argvp, char *input);
 107
 108/*
 109 * Is this mapped_device being deleted?
 110 */
 111int dm_deleting_md(struct mapped_device *md);
 112
 113/*
 114 * Is this mapped_device suspended?
 115 */
 116int dm_suspended_md(struct mapped_device *md);
 117
 118/*
 119 * The device-mapper can be driven through one of two interfaces;
 120 * ioctl or filesystem, depending which patch you have applied.
 121 */
 122int dm_interface_init(void);
 123void dm_interface_exit(void);
 124
 125/*
 126 * sysfs interface
 127 */
 128int dm_sysfs_init(struct mapped_device *md);
 129void dm_sysfs_exit(struct mapped_device *md);
 130struct kobject *dm_kobject(struct mapped_device *md);
 131struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
 132
 133/*
 134 * Targets for linear and striped mappings
 135 */
 136int dm_linear_init(void);
 137void dm_linear_exit(void);
 138
 139int dm_stripe_init(void);
 140void dm_stripe_exit(void);
 141
 142/*
 143 * mapped_device operations
 144 */
 145void dm_destroy(struct mapped_device *md);
 146void dm_destroy_immediate(struct mapped_device *md);
 147int dm_open_count(struct mapped_device *md);
 148int dm_lock_for_deletion(struct mapped_device *md);
 149
 150int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
 151                      unsigned cookie);
 152
 153int dm_io_init(void);
 154void dm_io_exit(void);
 155
 156int dm_kcopyd_init(void);
 157void dm_kcopyd_exit(void);
 158
 159/*
 160 * Mempool operations
 161 */
 162struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity);
 163void dm_free_md_mempools(struct dm_md_mempools *pools);
 164
 165#endif
 166