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#include <linux/refcount.h>
  23
  24#include "dm-stats.h"
  25
  26/*
  27 * Suspend feature flags
  28 */
  29#define DM_SUSPEND_LOCKFS_FLAG          (1 << 0)
  30#define DM_SUSPEND_NOFLUSH_FLAG         (1 << 1)
  31
  32/*
  33 * Status feature flags
  34 */
  35#define DM_STATUS_NOFLUSH_FLAG          (1 << 0)
  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        refcount_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_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);
  66enum dm_queue_mode dm_table_get_type(struct dm_table *t);
  67struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
  68struct dm_target *dm_table_get_immutable_target(struct dm_table *t);
  69struct dm_target *dm_table_get_wildcard_target(struct dm_table *t);
  70bool dm_table_bio_based(struct dm_table *t);
  71bool dm_table_request_based(struct dm_table *t);
  72void dm_table_free_md_mempools(struct dm_table *t);
  73struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
  74bool dm_table_supports_dax(struct dm_table *t, iterate_devices_callout_fn fn,
  75                           int *blocksize);
  76int device_supports_dax(struct dm_target *ti, struct dm_dev *dev,
  77                           sector_t start, sector_t len, void *data);
  78
  79void dm_lock_md_type(struct mapped_device *md);
  80void dm_unlock_md_type(struct mapped_device *md);
  81void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type);
  82enum dm_queue_mode dm_get_md_type(struct mapped_device *md);
  83struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
  84
  85int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t);
  86
  87/*
  88 * To check whether the target type is bio-based or not (request-based).
  89 */
  90#define dm_target_bio_based(t) ((t)->type->map != NULL)
  91
  92/*
  93 * To check whether the target type is request-based or not (bio-based).
  94 */
  95#define dm_target_request_based(t) ((t)->type->clone_and_map_rq != NULL)
  96
  97/*
  98 * To check whether the target type is a hybrid (capable of being
  99 * either request-based or bio-based).
 100 */
 101#define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))
 102
 103/*-----------------------------------------------------------------
 104 * A registry of target types.
 105 *---------------------------------------------------------------*/
 106int dm_target_init(void);
 107void dm_target_exit(void);
 108struct target_type *dm_get_target_type(const char *name);
 109void dm_put_target_type(struct target_type *tt);
 110int dm_target_iterate(void (*iter_func)(struct target_type *tt,
 111                                        void *param), void *param);
 112
 113int dm_split_args(int *argc, char ***argvp, char *input);
 114
 115/*
 116 * Is this mapped_device being deleted?
 117 */
 118int dm_deleting_md(struct mapped_device *md);
 119
 120/*
 121 * Is this mapped_device suspended?
 122 */
 123int dm_suspended_md(struct mapped_device *md);
 124
 125/*
 126 * Internal suspend and resume methods.
 127 */
 128int dm_suspended_internally_md(struct mapped_device *md);
 129void dm_internal_suspend_fast(struct mapped_device *md);
 130void dm_internal_resume_fast(struct mapped_device *md);
 131void dm_internal_suspend_noflush(struct mapped_device *md);
 132void dm_internal_resume(struct mapped_device *md);
 133
 134/*
 135 * Test if the device is scheduled for deferred remove.
 136 */
 137int dm_test_deferred_remove_flag(struct mapped_device *md);
 138
 139/*
 140 * Try to remove devices marked for deferred removal.
 141 */
 142void dm_deferred_remove(void);
 143
 144/*
 145 * The device-mapper can be driven through one of two interfaces;
 146 * ioctl or filesystem, depending which patch you have applied.
 147 */
 148int dm_interface_init(void);
 149void dm_interface_exit(void);
 150
 151/*
 152 * sysfs interface
 153 */
 154int dm_sysfs_init(struct mapped_device *md);
 155void dm_sysfs_exit(struct mapped_device *md);
 156struct kobject *dm_kobject(struct mapped_device *md);
 157struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
 158
 159/*
 160 * The kobject helper
 161 */
 162void dm_kobject_release(struct kobject *kobj);
 163
 164/*
 165 * Targets for linear and striped mappings
 166 */
 167int dm_linear_init(void);
 168void dm_linear_exit(void);
 169
 170int dm_stripe_init(void);
 171void dm_stripe_exit(void);
 172
 173/*
 174 * mapped_device operations
 175 */
 176void dm_destroy(struct mapped_device *md);
 177void dm_destroy_immediate(struct mapped_device *md);
 178int dm_open_count(struct mapped_device *md);
 179int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);
 180int dm_cancel_deferred_remove(struct mapped_device *md);
 181int dm_request_based(struct mapped_device *md);
 182sector_t dm_get_size(struct mapped_device *md);
 183struct request_queue *dm_get_md_queue(struct mapped_device *md);
 184int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
 185                        struct dm_dev **result);
 186void dm_put_table_device(struct mapped_device *md, struct dm_dev *d);
 187struct dm_stats *dm_get_stats(struct mapped_device *md);
 188
 189int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
 190                      unsigned cookie);
 191
 192void dm_internal_suspend(struct mapped_device *md);
 193void dm_internal_resume(struct mapped_device *md);
 194
 195int dm_io_init(void);
 196void dm_io_exit(void);
 197
 198int dm_kcopyd_init(void);
 199void dm_kcopyd_exit(void);
 200
 201/*
 202 * Mempool operations
 203 */
 204struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type,
 205                                            unsigned integrity, unsigned per_bio_data_size,
 206                                            unsigned min_pool_size);
 207void dm_free_md_mempools(struct dm_md_mempools *pools);
 208
 209/*
 210 * Various helpers
 211 */
 212unsigned dm_get_reserved_bio_based_ios(void);
 213
 214#endif
 215