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/moduleparam.h>
  17#include <linux/blkdev.h>
  18#include <linux/backing-dev.h>
  19#include <linux/hdreg.h>
  20#include <linux/completion.h>
  21#include <linux/kobject.h>
  22
  23#include "dm-stats.h"
  24
  25/*
  26 * Suspend feature flags
  27 */
  28#define DM_SUSPEND_LOCKFS_FLAG          (1 << 0)
  29#define DM_SUSPEND_NOFLUSH_FLAG         (1 << 1)
  30
  31/*
  32 * Status feature flags
  33 */
  34#define DM_STATUS_NOFLUSH_FLAG          (1 << 0)
  35
  36/*
  37 * List of devices that a metadevice uses and should open/close.
  38 */
  39struct dm_dev_internal {
  40        struct list_head list;
  41        atomic_t count;
  42        struct dm_dev *dm_dev;
  43};
  44
  45struct dm_table;
  46struct dm_md_mempools;
  47
  48/*-----------------------------------------------------------------
  49 * Internal table functions.
  50 *---------------------------------------------------------------*/
  51void dm_table_destroy(struct dm_table *t);
  52void dm_table_event_callback(struct dm_table *t,
  53                             void (*fn)(void *), void *context);
  54struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
  55struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
  56bool dm_table_has_no_data_devices(struct dm_table *table);
  57int dm_calculate_queue_limits(struct dm_table *table,
  58                              struct queue_limits *limits);
  59void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
  60                               struct queue_limits *limits);
  61struct list_head *dm_table_get_devices(struct dm_table *t);
  62void dm_table_presuspend_targets(struct dm_table *t);
  63void dm_table_presuspend_undo_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);
  67enum dm_queue_mode dm_table_get_type(struct dm_table *t);
  68struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
  69struct dm_target *dm_table_get_immutable_target(struct dm_table *t);
  70struct dm_target *dm_table_get_wildcard_target(struct dm_table *t);
  71bool dm_table_bio_based(struct dm_table *t);
  72bool dm_table_request_based(struct dm_table *t);
  73bool dm_table_all_blk_mq_devices(struct dm_table *t);
  74void dm_table_free_md_mempools(struct dm_table *t);
  75struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
  76
  77void dm_lock_md_type(struct mapped_device *md);
  78void dm_unlock_md_type(struct mapped_device *md);
  79void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type);
  80enum dm_queue_mode dm_get_md_type(struct mapped_device *md);
  81struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
  82
  83int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t);
  84
  85/*
  86 * To check the return value from dm_table_find_target().
  87 */
  88#define dm_target_is_valid(t) ((t)->table)
  89
  90/*
  91 * To check whether the target type is bio-based or not (request-based).
  92 */
  93#define dm_target_bio_based(t) ((t)->type->map != NULL)
  94
  95/*
  96 * To check whether the target type is request-based or not (bio-based).
  97 */
  98#define dm_target_request_based(t) ((t)->type->clone_and_map_rq != NULL)
  99
 100/*
 101 * To check whether the target type is a hybrid (capable of being
 102 * either request-based or bio-based).
 103 */
 104#define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))
 105
 106/*-----------------------------------------------------------------
 107 * A registry of target types.
 108 *---------------------------------------------------------------*/
 109int dm_target_init(void);
 110void dm_target_exit(void);
 111struct target_type *dm_get_target_type(const char *name);
 112void dm_put_target_type(struct target_type *tt);
 113int dm_target_iterate(void (*iter_func)(struct target_type *tt,
 114                                        void *param), void *param);
 115
 116int dm_split_args(int *argc, char ***argvp, char *input);
 117
 118/*
 119 * Is this mapped_device being deleted?
 120 */
 121int dm_deleting_md(struct mapped_device *md);
 122
 123/*
 124 * Is this mapped_device suspended?
 125 */
 126int dm_suspended_md(struct mapped_device *md);
 127
 128/*
 129 * Internal suspend and resume methods.
 130 */
 131int dm_suspended_internally_md(struct mapped_device *md);
 132void dm_internal_suspend_fast(struct mapped_device *md);
 133void dm_internal_resume_fast(struct mapped_device *md);
 134void dm_internal_suspend_noflush(struct mapped_device *md);
 135void dm_internal_resume(struct mapped_device *md);
 136
 137/*
 138 * Test if the device is scheduled for deferred remove.
 139 */
 140int dm_test_deferred_remove_flag(struct mapped_device *md);
 141
 142/*
 143 * Try to remove devices marked for deferred removal.
 144 */
 145void dm_deferred_remove(void);
 146
 147/*
 148 * The device-mapper can be driven through one of two interfaces;
 149 * ioctl or filesystem, depending which patch you have applied.
 150 */
 151int dm_interface_init(void);
 152void dm_interface_exit(void);
 153
 154/*
 155 * sysfs interface
 156 */
 157int dm_sysfs_init(struct mapped_device *md);
 158void dm_sysfs_exit(struct mapped_device *md);
 159struct kobject *dm_kobject(struct mapped_device *md);
 160struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
 161
 162/*
 163 * The kobject helper
 164 */
 165void dm_kobject_release(struct kobject *kobj);
 166
 167/*
 168 * Targets for linear and striped mappings
 169 */
 170int dm_linear_init(void);
 171void dm_linear_exit(void);
 172
 173int dm_stripe_init(void);
 174void dm_stripe_exit(void);
 175
 176/*
 177 * mapped_device operations
 178 */
 179void dm_destroy(struct mapped_device *md);
 180void dm_destroy_immediate(struct mapped_device *md);
 181int dm_open_count(struct mapped_device *md);
 182int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);
 183int dm_cancel_deferred_remove(struct mapped_device *md);
 184int dm_request_based(struct mapped_device *md);
 185sector_t dm_get_size(struct mapped_device *md);
 186struct request_queue *dm_get_md_queue(struct mapped_device *md);
 187int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
 188                        struct dm_dev **result);
 189void dm_put_table_device(struct mapped_device *md, struct dm_dev *d);
 190struct dm_stats *dm_get_stats(struct mapped_device *md);
 191
 192int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
 193                      unsigned cookie);
 194
 195void dm_internal_suspend(struct mapped_device *md);
 196void dm_internal_resume(struct mapped_device *md);
 197
 198int dm_io_init(void);
 199void dm_io_exit(void);
 200
 201int dm_kcopyd_init(void);
 202void dm_kcopyd_exit(void);
 203
 204/*
 205 * Mempool operations
 206 */
 207struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type,
 208                                            unsigned integrity, unsigned per_bio_data_size);
 209void dm_free_md_mempools(struct dm_md_mempools *pools);
 210
 211/*
 212 * Various helpers
 213 */
 214unsigned dm_get_reserved_bio_based_ios(void);
 215
 216#endif
 217