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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#include <linux/log2.h>
24
25#include "dm-stats.h"
26
27/*
28 * Suspend feature flags
29 */
30#define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
31#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
32
33/*
34 * Status feature flags
35 */
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 being
97 * 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);
105void dm_zone_endio(struct dm_io *io, struct bio *clone);
106#ifdef CONFIG_BLK_DEV_ZONED
107void dm_cleanup_zoned_dev(struct mapped_device *md);
108int dm_blk_report_zones(struct gendisk *disk, sector_t sector,
109 unsigned int nr_zones, report_zones_cb cb, void *data);
110bool dm_is_zone_write(struct mapped_device *md, struct bio *bio);
111int dm_zone_map_bio(struct dm_target_io *io);
112#else
113static inline void dm_cleanup_zoned_dev(struct mapped_device *md) {}
114#define dm_blk_report_zones NULL
115static inline bool dm_is_zone_write(struct mapped_device *md, struct bio *bio)
116{
117 return false;
118}
119static inline int dm_zone_map_bio(struct dm_target_io *tio)
120{
121 return DM_MAPIO_KILL;
122}
123#endif
124
125/*
126 *---------------------------------------------------------------
127 * A registry of target types.
128 *---------------------------------------------------------------
129 */
130int dm_target_init(void);
131void dm_target_exit(void);
132struct target_type *dm_get_target_type(const char *name);
133void dm_put_target_type(struct target_type *tt);
134int dm_target_iterate(void (*iter_func)(struct target_type *tt,
135 void *param), void *param);
136
137int dm_split_args(int *argc, char ***argvp, char *input);
138
139/*
140 * Is this mapped_device being deleted?
141 */
142int dm_deleting_md(struct mapped_device *md);
143
144/*
145 * Is this mapped_device suspended?
146 */
147int dm_suspended_md(struct mapped_device *md);
148
149/*
150 * Internal suspend and resume methods.
151 */
152int dm_suspended_internally_md(struct mapped_device *md);
153void dm_internal_suspend_fast(struct mapped_device *md);
154void dm_internal_resume_fast(struct mapped_device *md);
155void dm_internal_suspend_noflush(struct mapped_device *md);
156void dm_internal_resume(struct mapped_device *md);
157
158/*
159 * Test if the device is scheduled for deferred remove.
160 */
161int dm_test_deferred_remove_flag(struct mapped_device *md);
162
163/*
164 * Try to remove devices marked for deferred removal.
165 */
166void dm_deferred_remove(void);
167
168/*
169 * The device-mapper can be driven through one of two interfaces;
170 * ioctl or filesystem, depending which patch you have applied.
171 */
172int dm_interface_init(void);
173void dm_interface_exit(void);
174
175/*
176 * sysfs interface
177 */
178int dm_sysfs_init(struct mapped_device *md);
179void dm_sysfs_exit(struct mapped_device *md);
180struct kobject *dm_kobject(struct mapped_device *md);
181struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
182
183/*
184 * The kobject helper
185 */
186void dm_kobject_release(struct kobject *kobj);
187
188/*
189 * Targets for linear and striped mappings
190 */
191int linear_map(struct dm_target *ti, struct bio *bio);
192int dm_linear_init(void);
193void dm_linear_exit(void);
194
195int stripe_map(struct dm_target *ti, struct bio *bio);
196int dm_stripe_init(void);
197void dm_stripe_exit(void);
198
199/*
200 * mapped_device operations
201 */
202void dm_destroy(struct mapped_device *md);
203void dm_destroy_immediate(struct mapped_device *md);
204int dm_open_count(struct mapped_device *md);
205int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);
206int dm_cancel_deferred_remove(struct mapped_device *md);
207int dm_request_based(struct mapped_device *md);
208int dm_get_table_device(struct mapped_device *md, dev_t dev, blk_mode_t mode,
209 struct dm_dev **result);
210void dm_put_table_device(struct mapped_device *md, struct dm_dev *d);
211
212int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
213 unsigned int cookie, bool need_resize_uevent);
214
215int dm_io_init(void);
216void dm_io_exit(void);
217
218int dm_kcopyd_init(void);
219void dm_kcopyd_exit(void);
220
221/*
222 * Mempool operations
223 */
224void dm_free_md_mempools(struct dm_md_mempools *pools);
225
226/*
227 * Various helpers
228 */
229unsigned int dm_get_reserved_bio_based_ios(void);
230
231#define DM_HASH_LOCKS_MAX 64
232
233static inline unsigned int dm_num_hash_locks(void)
234{
235 unsigned int num_locks = roundup_pow_of_two(num_online_cpus()) << 1;
236
237 return min_t(unsigned int, num_locks, DM_HASH_LOCKS_MAX);
238}
239
240#define DM_HASH_LOCKS_MULT 4294967291ULL
241#define DM_HASH_LOCKS_SHIFT 6
242
243static inline unsigned int dm_hash_locks_index(sector_t block,
244 unsigned int num_locks)
245{
246 sector_t h1 = (block * DM_HASH_LOCKS_MULT) >> DM_HASH_LOCKS_SHIFT;
247 sector_t h2 = h1 >> DM_HASH_LOCKS_SHIFT;
248
249 return (h1 ^ h2) & (num_locks - 1);
250}
251
252#endif
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 * Type of table and mapped_device's mempool
27 */
28#define DM_TYPE_NONE 0
29#define DM_TYPE_BIO_BASED 1
30#define DM_TYPE_REQUEST_BASED 2
31
32/*
33 * List of devices that a metadevice uses and should open/close.
34 */
35struct dm_dev_internal {
36 struct list_head list;
37 atomic_t count;
38 struct dm_dev dm_dev;
39};
40
41struct dm_table;
42struct dm_md_mempools;
43
44/*-----------------------------------------------------------------
45 * Internal table functions.
46 *---------------------------------------------------------------*/
47void dm_table_destroy(struct dm_table *t);
48void dm_table_event_callback(struct dm_table *t,
49 void (*fn)(void *), void *context);
50struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
51struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
52int dm_calculate_queue_limits(struct dm_table *table,
53 struct queue_limits *limits);
54void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
55 struct queue_limits *limits);
56struct list_head *dm_table_get_devices(struct dm_table *t);
57void dm_table_presuspend_targets(struct dm_table *t);
58void dm_table_postsuspend_targets(struct dm_table *t);
59int dm_table_resume_targets(struct dm_table *t);
60int dm_table_any_congested(struct dm_table *t, int bdi_bits);
61int dm_table_any_busy_target(struct dm_table *t);
62unsigned dm_table_get_type(struct dm_table *t);
63bool dm_table_request_based(struct dm_table *t);
64bool dm_table_supports_discards(struct dm_table *t);
65int dm_table_alloc_md_mempools(struct dm_table *t);
66void dm_table_free_md_mempools(struct dm_table *t);
67struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
68
69int dm_queue_merge_is_compulsory(struct request_queue *q);
70
71void dm_lock_md_type(struct mapped_device *md);
72void dm_unlock_md_type(struct mapped_device *md);
73void dm_set_md_type(struct mapped_device *md, unsigned type);
74unsigned dm_get_md_type(struct mapped_device *md);
75
76int dm_setup_md_queue(struct mapped_device *md);
77
78/*
79 * To check the return value from dm_table_find_target().
80 */
81#define dm_target_is_valid(t) ((t)->table)
82
83/*
84 * To check whether the target type is request-based or not (bio-based).
85 */
86#define dm_target_request_based(t) ((t)->type->map_rq != NULL)
87
88/*-----------------------------------------------------------------
89 * A registry of target types.
90 *---------------------------------------------------------------*/
91int dm_target_init(void);
92void dm_target_exit(void);
93struct target_type *dm_get_target_type(const char *name);
94void dm_put_target_type(struct target_type *tt);
95int dm_target_iterate(void (*iter_func)(struct target_type *tt,
96 void *param), void *param);
97
98int dm_split_args(int *argc, char ***argvp, char *input);
99
100/*
101 * Is this mapped_device being deleted?
102 */
103int dm_deleting_md(struct mapped_device *md);
104
105/*
106 * Is this mapped_device suspended?
107 */
108int dm_suspended_md(struct mapped_device *md);
109
110/*
111 * The device-mapper can be driven through one of two interfaces;
112 * ioctl or filesystem, depending which patch you have applied.
113 */
114int dm_interface_init(void);
115void dm_interface_exit(void);
116
117/*
118 * sysfs interface
119 */
120int dm_sysfs_init(struct mapped_device *md);
121void dm_sysfs_exit(struct mapped_device *md);
122struct kobject *dm_kobject(struct mapped_device *md);
123struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
124
125/*
126 * Targets for linear and striped mappings
127 */
128int dm_linear_init(void);
129void dm_linear_exit(void);
130
131int dm_stripe_init(void);
132void dm_stripe_exit(void);
133
134/*
135 * mapped_device operations
136 */
137void dm_destroy(struct mapped_device *md);
138void dm_destroy_immediate(struct mapped_device *md);
139int dm_open_count(struct mapped_device *md);
140int dm_lock_for_deletion(struct mapped_device *md);
141
142int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
143 unsigned cookie);
144
145int dm_io_init(void);
146void dm_io_exit(void);
147
148int dm_kcopyd_init(void);
149void dm_kcopyd_exit(void);
150
151/*
152 * Mempool operations
153 */
154struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity);
155void dm_free_md_mempools(struct dm_md_mempools *pools);
156
157#endif