xref: /kernel/linux/linux-5.10/drivers/md/dm.h (revision 8c2ecf20) 
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_not_dax_capable(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);
182int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
183			struct dm_dev **result);
184void dm_put_table_device(struct mapped_device *md, struct dm_dev *d);
185
186int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
187		      unsigned cookie);
188
189void dm_internal_suspend(struct mapped_device *md);
190void dm_internal_resume(struct mapped_device *md);
191
192int dm_io_init(void);
193void dm_io_exit(void);
194
195int dm_kcopyd_init(void);
196void dm_kcopyd_exit(void);
197
198/*
199 * Mempool operations
200 */
201struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type,
202					    unsigned integrity, unsigned per_bio_data_size,
203					    unsigned min_pool_size);
204void dm_free_md_mempools(struct dm_md_mempools *pools);
205
206/*
207 * Various helpers
208 */
209unsigned dm_get_reserved_bio_based_ios(void);
210
211#endif
212