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Linux kernel mirror (for testing)
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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/hdreg.h>
18#include <linux/completion.h>
19#include <linux/kobject.h>
20
21#include "dm-stats.h"
22
23/*
24 * Suspend feature flags
25 */
26#define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
27#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
28
29/*
30 * Status feature flags
31 */
32#define DM_STATUS_NOFLUSH_FLAG (1 << 0)
33
34/*
35 * Type of table and mapped_device's mempool
36 */
37#define DM_TYPE_NONE 0
38#define DM_TYPE_BIO_BASED 1
39#define DM_TYPE_REQUEST_BASED 2
40
41/*
42 * List of devices that a metadevice uses and should open/close.
43 */
44struct dm_dev_internal {
45 struct list_head list;
46 atomic_t count;
47 struct dm_dev dm_dev;
48};
49
50struct dm_table;
51struct dm_md_mempools;
52
53/*-----------------------------------------------------------------
54 * Internal table functions.
55 *---------------------------------------------------------------*/
56void dm_table_destroy(struct dm_table *t);
57void dm_table_event_callback(struct dm_table *t,
58 void (*fn)(void *), void *context);
59struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
60struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
61bool dm_table_has_no_data_devices(struct dm_table *table);
62int dm_calculate_queue_limits(struct dm_table *table,
63 struct queue_limits *limits);
64void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
65 struct queue_limits *limits);
66struct list_head *dm_table_get_devices(struct dm_table *t);
67void dm_table_presuspend_targets(struct dm_table *t);
68void dm_table_postsuspend_targets(struct dm_table *t);
69int dm_table_resume_targets(struct dm_table *t);
70int dm_table_any_congested(struct dm_table *t, int bdi_bits);
71int dm_table_any_busy_target(struct dm_table *t);
72unsigned dm_table_get_type(struct dm_table *t);
73struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
74bool dm_table_request_based(struct dm_table *t);
75bool dm_table_supports_discards(struct dm_table *t);
76void dm_table_free_md_mempools(struct dm_table *t);
77struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
78
79int dm_queue_merge_is_compulsory(struct request_queue *q);
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
104/*
105 * To check whether the target type is a hybrid (capable of being
106 * either request-based or bio-based).
107 */
108#define dm_target_hybrid(t) (dm_target_bio_based(t) && dm_target_request_based(t))
109
110/*-----------------------------------------------------------------
111 * A registry of target types.
112 *---------------------------------------------------------------*/
113int dm_target_init(void);
114void dm_target_exit(void);
115struct target_type *dm_get_target_type(const char *name);
116void dm_put_target_type(struct target_type *tt);
117int dm_target_iterate(void (*iter_func)(struct target_type *tt,
118 void *param), void *param);
119
120int dm_split_args(int *argc, char ***argvp, char *input);
121
122/*
123 * Is this mapped_device being deleted?
124 */
125int dm_deleting_md(struct mapped_device *md);
126
127/*
128 * Is this mapped_device suspended?
129 */
130int dm_suspended_md(struct mapped_device *md);
131
132/*
133 * Test if the device is scheduled for deferred remove.
134 */
135int dm_test_deferred_remove_flag(struct mapped_device *md);
136
137/*
138 * Try to remove devices marked for deferred removal.
139 */
140void dm_deferred_remove(void);
141
142/*
143 * The device-mapper can be driven through one of two interfaces;
144 * ioctl or filesystem, depending which patch you have applied.
145 */
146int dm_interface_init(void);
147void dm_interface_exit(void);
148
149/*
150 * sysfs interface
151 */
152struct dm_kobject_holder {
153 struct kobject kobj;
154 struct completion completion;
155};
156
157static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
158{
159 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
160}
161
162int dm_sysfs_init(struct mapped_device *md);
163void dm_sysfs_exit(struct mapped_device *md);
164struct kobject *dm_kobject(struct mapped_device *md);
165struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
166
167/*
168 * The kobject helper
169 */
170void dm_kobject_release(struct kobject *kobj);
171
172/*
173 * Targets for linear and striped mappings
174 */
175int dm_linear_init(void);
176void dm_linear_exit(void);
177
178int dm_stripe_init(void);
179void dm_stripe_exit(void);
180
181/*
182 * mapped_device operations
183 */
184void dm_destroy(struct mapped_device *md);
185void dm_destroy_immediate(struct mapped_device *md);
186int dm_open_count(struct mapped_device *md);
187int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred);
188int dm_cancel_deferred_remove(struct mapped_device *md);
189int dm_request_based(struct mapped_device *md);
190sector_t dm_get_size(struct mapped_device *md);
191struct request_queue *dm_get_md_queue(struct mapped_device *md);
192struct dm_stats *dm_get_stats(struct mapped_device *md);
193
194int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
195 unsigned cookie);
196
197void dm_internal_suspend(struct mapped_device *md);
198void dm_internal_resume(struct mapped_device *md);
199
200int dm_io_init(void);
201void dm_io_exit(void);
202
203int dm_kcopyd_init(void);
204void dm_kcopyd_exit(void);
205
206/*
207 * Mempool operations
208 */
209struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size);
210void dm_free_md_mempools(struct dm_md_mempools *pools);
211
212/*
213 * Helpers that are used by DM core
214 */
215unsigned dm_get_reserved_bio_based_ios(void);
216unsigned dm_get_reserved_rq_based_ios(void);
217
218static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen)
219{
220 return !maxlen || strlen(result) + 1 >= maxlen;
221}
222
223#endif