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1/*2 * Internal header file for device mapper3 *4 * Copyright (C) 2001, 2002 Sistina Software5 * 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_H11#define DM_INTERNAL_H12 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#include <linux/log2.h>24 25#include "dm-stats.h"26 27/*28 * Suspend feature flags29 */30#define DM_SUSPEND_LOCKFS_FLAG (1 << 0)31#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)32 33/*34 * Status feature flags35 */36#define DM_STATUS_NOFLUSH_FLAG (1 << 0)37 38/*39 * List of devices that a metadevice uses and should open/close.40 */41struct dm_dev_internal {42 struct list_head list;43 refcount_t count;44 struct dm_dev *dm_dev;45};46 47struct dm_table;48struct dm_md_mempools;49struct dm_target_io;50struct dm_io;51 52/*53 *---------------------------------------------------------------54 * Internal table functions.55 *---------------------------------------------------------------56 */57void dm_table_event_callback(struct dm_table *t,58 void (*fn)(void *), void *context);59struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);60bool dm_table_has_no_data_devices(struct dm_table *table);61int dm_calculate_queue_limits(struct dm_table *table,62 struct queue_limits *limits);63int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,64 struct queue_limits *limits);65struct list_head *dm_table_get_devices(struct dm_table *t);66void dm_table_presuspend_targets(struct dm_table *t);67void dm_table_presuspend_undo_targets(struct dm_table *t);68void dm_table_postsuspend_targets(struct dm_table *t);69int dm_table_resume_targets(struct dm_table *t);70enum dm_queue_mode dm_table_get_type(struct dm_table *t);71struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);72struct dm_target *dm_table_get_immutable_target(struct dm_table *t);73struct dm_target *dm_table_get_wildcard_target(struct dm_table *t);74bool dm_table_bio_based(struct dm_table *t);75bool dm_table_request_based(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 whether the target type is bio-based or not (request-based).87 */88#define dm_target_bio_based(t) ((t)->type->map != NULL)89 90/*91 * To check whether the target type is request-based or not (bio-based).92 */93#define dm_target_request_based(t) ((t)->type->clone_and_map_rq != NULL)94 95/*96 * To check whether the target type is a hybrid (capable of being97 * either request-based or bio-based).98 */99#define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))100 101/*102 * Zoned targets related functions.103 */104int dm_set_zones_restrictions(struct dm_table *t, struct request_queue *q,105 struct queue_limits *lim);106int dm_revalidate_zones(struct dm_table *t, struct request_queue *q);107void dm_zone_endio(struct dm_io *io, struct bio *clone);108#ifdef CONFIG_BLK_DEV_ZONED109int dm_blk_report_zones(struct gendisk *disk, sector_t sector,110 unsigned int nr_zones, report_zones_cb cb, void *data);111bool dm_is_zone_write(struct mapped_device *md, struct bio *bio);112int dm_zone_get_reset_bitmap(struct mapped_device *md, struct dm_table *t,113 sector_t sector, unsigned int nr_zones,114 unsigned long *need_reset);115#else116#define dm_blk_report_zones NULL117static inline bool dm_is_zone_write(struct mapped_device *md, struct bio *bio)118{119 return false;120}121#endif122 123/*124 *---------------------------------------------------------------125 * A registry of target types.126 *---------------------------------------------------------------127 */128int dm_target_init(void);129void dm_target_exit(void);130struct target_type *dm_get_target_type(const char *name);131void dm_put_target_type(struct target_type *tt);132int dm_target_iterate(void (*iter_func)(struct target_type *tt,133 void *param), void *param);134 135int dm_split_args(int *argc, char ***argvp, char *input);136 137/*138 * Is this mapped_device being deleted?139 */140int dm_deleting_md(struct mapped_device *md);141 142/*143 * Is this mapped_device suspended?144 */145int dm_suspended_md(struct mapped_device *md);146 147/*148 * Internal suspend and resume methods.149 */150int dm_suspended_internally_md(struct mapped_device *md);151void dm_internal_suspend_fast(struct mapped_device *md);152void dm_internal_resume_fast(struct mapped_device *md);153void dm_internal_suspend_noflush(struct mapped_device *md);154void dm_internal_resume(struct mapped_device *md);155 156/*157 * Test if the device is scheduled for deferred remove.158 */159int dm_test_deferred_remove_flag(struct mapped_device *md);160 161/*162 * Try to remove devices marked for deferred removal.163 */164void dm_deferred_remove(void);165 166/*167 * The device-mapper can be driven through one of two interfaces;168 * ioctl or filesystem, depending which patch you have applied.169 */170int dm_interface_init(void);171void dm_interface_exit(void);172 173/*174 * sysfs interface175 */176int dm_sysfs_init(struct mapped_device *md);177void dm_sysfs_exit(struct mapped_device *md);178struct kobject *dm_kobject(struct mapped_device *md);179struct mapped_device *dm_get_from_kobject(struct kobject *kobj);180 181/*182 * The kobject helper183 */184void dm_kobject_release(struct kobject *kobj);185 186/*187 * Targets for linear and striped mappings188 */189int linear_map(struct dm_target *ti, struct bio *bio);190int dm_linear_init(void);191void dm_linear_exit(void);192 193int stripe_map(struct dm_target *ti, struct bio *bio);194int dm_stripe_init(void);195void dm_stripe_exit(void);196 197/*198 * mapped_device operations199 */200void dm_destroy(struct mapped_device *md);201void dm_destroy_immediate(struct mapped_device *md);202int dm_open_count(struct mapped_device *md);203int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);204int dm_cancel_deferred_remove(struct mapped_device *md);205int dm_request_based(struct mapped_device *md);206int dm_get_table_device(struct mapped_device *md, dev_t dev, blk_mode_t mode,207 struct dm_dev **result);208void dm_put_table_device(struct mapped_device *md, struct dm_dev *d);209 210int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,211 unsigned int cookie, bool need_resize_uevent);212 213int dm_io_init(void);214void dm_io_exit(void);215 216int dm_kcopyd_init(void);217void dm_kcopyd_exit(void);218 219/*220 * Mempool operations221 */222void dm_free_md_mempools(struct dm_md_mempools *pools);223 224/*225 * Various helpers226 */227unsigned int dm_get_reserved_bio_based_ios(void);228 229#define DM_HASH_LOCKS_MAX 64230 231static inline unsigned int dm_num_hash_locks(void)232{233 unsigned int num_locks = roundup_pow_of_two(num_online_cpus()) << 1;234 235 return min_t(unsigned int, num_locks, DM_HASH_LOCKS_MAX);236}237 238#define DM_HASH_LOCKS_MULT 4294967291ULL239#define DM_HASH_LOCKS_SHIFT 6240 241static inline unsigned int dm_hash_locks_index(sector_t block,242 unsigned int num_locks)243{244 sector_t h1 = (block * DM_HASH_LOCKS_MULT) >> DM_HASH_LOCKS_SHIFT;245 sector_t h2 = h1 >> DM_HASH_LOCKS_SHIFT;246 247 return (h1 ^ h2) & (num_locks - 1);248}249 250#endif251