tjh.dev
Linux kernel mirror (for testing)
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kernel
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linux
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/backing-dev.h>
18#include <linux/hdreg.h>
19#include <linux/completion.h>
20#include <linux/kobject.h>
21
22#include "dm-stats.h"
23
24/*
25 * Suspend feature flags
26 */
27#define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
28#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
29
30/*
31 * Status feature flags
32 */
33#define DM_STATUS_NOFLUSH_FLAG (1 << 0)
34
35/*
36 * Type of table and mapped_device's mempool
37 */
38#define DM_TYPE_NONE 0
39#define DM_TYPE_BIO_BASED 1
40#define DM_TYPE_REQUEST_BASED 2
41#define DM_TYPE_MQ_REQUEST_BASED 3
42
43/*
44 * List of devices that a metadevice uses and should open/close.
45 */
46struct dm_dev_internal {
47 struct list_head list;
48 atomic_t count;
49 struct dm_dev *dm_dev;
50};
51
52struct dm_table;
53struct dm_md_mempools;
54
55/*-----------------------------------------------------------------
56 * Internal table functions.
57 *---------------------------------------------------------------*/
58void dm_table_destroy(struct dm_table *t);
59void dm_table_event_callback(struct dm_table *t,
60 void (*fn)(void *), void *context);
61struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
62struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
63bool dm_table_has_no_data_devices(struct dm_table *table);
64int dm_calculate_queue_limits(struct dm_table *table,
65 struct queue_limits *limits);
66void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
67 struct queue_limits *limits);
68struct list_head *dm_table_get_devices(struct dm_table *t);
69void dm_table_presuspend_targets(struct dm_table *t);
70void dm_table_presuspend_undo_targets(struct dm_table *t);
71void dm_table_postsuspend_targets(struct dm_table *t);
72int dm_table_resume_targets(struct dm_table *t);
73int dm_table_any_congested(struct dm_table *t, int bdi_bits);
74unsigned dm_table_get_type(struct dm_table *t);
75struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
76bool dm_table_request_based(struct dm_table *t);
77bool dm_table_mq_request_based(struct dm_table *t);
78void dm_table_free_md_mempools(struct dm_table *t);
79struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
80
81void dm_lock_md_type(struct mapped_device *md);
82void dm_unlock_md_type(struct mapped_device *md);
83void dm_set_md_type(struct mapped_device *md, unsigned type);
84unsigned dm_get_md_type(struct mapped_device *md);
85struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
86
87int dm_setup_md_queue(struct mapped_device *md);
88
89/*
90 * To check the return value from dm_table_find_target().
91 */
92#define dm_target_is_valid(t) ((t)->table)
93
94/*
95 * To check whether the target type is bio-based or not (request-based).
96 */
97#define dm_target_bio_based(t) ((t)->type->map != NULL)
98
99/*
100 * To check whether the target type is request-based or not (bio-based).
101 */
102#define dm_target_request_based(t) (((t)->type->map_rq != NULL) || \
103 ((t)->type->clone_and_map_rq != NULL))
104
105/*
106 * To check whether the target type is a hybrid (capable of being
107 * either request-based or bio-based).
108 */
109#define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))
110
111/*-----------------------------------------------------------------
112 * A registry of target types.
113 *---------------------------------------------------------------*/
114int dm_target_init(void);
115void dm_target_exit(void);
116struct target_type *dm_get_target_type(const char *name);
117void dm_put_target_type(struct target_type *tt);
118int dm_target_iterate(void (*iter_func)(struct target_type *tt,
119 void *param), void *param);
120
121int dm_split_args(int *argc, char ***argvp, char *input);
122
123/*
124 * Is this mapped_device being deleted?
125 */
126int dm_deleting_md(struct mapped_device *md);
127
128/*
129 * Is this mapped_device suspended?
130 */
131int dm_suspended_md(struct mapped_device *md);
132
133/*
134 * Internal suspend and resume methods.
135 */
136int dm_suspended_internally_md(struct mapped_device *md);
137void dm_internal_suspend_fast(struct mapped_device *md);
138void dm_internal_resume_fast(struct mapped_device *md);
139void dm_internal_suspend_noflush(struct mapped_device *md);
140void dm_internal_resume(struct mapped_device *md);
141
142/*
143 * Test if the device is scheduled for deferred remove.
144 */
145int dm_test_deferred_remove_flag(struct mapped_device *md);
146
147/*
148 * Try to remove devices marked for deferred removal.
149 */
150void dm_deferred_remove(void);
151
152/*
153 * The device-mapper can be driven through one of two interfaces;
154 * ioctl or filesystem, depending which patch you have applied.
155 */
156int dm_interface_init(void);
157void dm_interface_exit(void);
158
159/*
160 * sysfs interface
161 */
162struct dm_kobject_holder {
163 struct kobject kobj;
164 struct completion completion;
165};
166
167static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
168{
169 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
170}
171
172int dm_sysfs_init(struct mapped_device *md);
173void dm_sysfs_exit(struct mapped_device *md);
174struct kobject *dm_kobject(struct mapped_device *md);
175struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
176
177/*
178 * The kobject helper
179 */
180void dm_kobject_release(struct kobject *kobj);
181
182/*
183 * Targets for linear and striped mappings
184 */
185int dm_linear_init(void);
186void dm_linear_exit(void);
187
188int dm_stripe_init(void);
189void dm_stripe_exit(void);
190
191/*
192 * mapped_device operations
193 */
194void dm_destroy(struct mapped_device *md);
195void dm_destroy_immediate(struct mapped_device *md);
196int dm_open_count(struct mapped_device *md);
197int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);
198int dm_cancel_deferred_remove(struct mapped_device *md);
199int dm_request_based(struct mapped_device *md);
200sector_t dm_get_size(struct mapped_device *md);
201struct request_queue *dm_get_md_queue(struct mapped_device *md);
202int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
203 struct dm_dev **result);
204void dm_put_table_device(struct mapped_device *md, struct dm_dev *d);
205struct dm_stats *dm_get_stats(struct mapped_device *md);
206
207int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
208 unsigned cookie);
209
210void dm_internal_suspend(struct mapped_device *md);
211void dm_internal_resume(struct mapped_device *md);
212
213bool dm_use_blk_mq(struct mapped_device *md);
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 */
224struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, unsigned type,
225 unsigned integrity, unsigned per_bio_data_size);
226void dm_free_md_mempools(struct dm_md_mempools *pools);
227
228/*
229 * Helpers that are used by DM core
230 */
231unsigned dm_get_reserved_bio_based_ios(void);
232unsigned dm_get_reserved_rq_based_ios(void);
233
234static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen)
235{
236 return !maxlen || strlen(result) + 1 >= maxlen;
237}
238
239ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf);
240ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
241 const char *buf, size_t count);
242
243#endif