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 | */ |
41 | struct dm_dev_internal { |
42 | struct list_head list; |
43 | refcount_t count; |
44 | struct dm_dev *dm_dev; |
45 | }; |
46 | |
47 | struct dm_table; |
48 | struct dm_md_mempools; |
49 | struct dm_target_io; |
50 | struct dm_io; |
51 | |
52 | /* |
53 | *--------------------------------------------------------------- |
54 | * Internal table functions. |
55 | *--------------------------------------------------------------- |
56 | */ |
57 | void dm_table_event_callback(struct dm_table *t, |
58 | void (*fn)(void *), void *context); |
59 | struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector); |
60 | bool dm_table_has_no_data_devices(struct dm_table *table); |
61 | int dm_calculate_queue_limits(struct dm_table *table, |
62 | struct queue_limits *limits); |
63 | int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, |
64 | struct queue_limits *limits); |
65 | struct list_head *dm_table_get_devices(struct dm_table *t); |
66 | void dm_table_presuspend_targets(struct dm_table *t); |
67 | void dm_table_presuspend_undo_targets(struct dm_table *t); |
68 | void dm_table_postsuspend_targets(struct dm_table *t); |
69 | int dm_table_resume_targets(struct dm_table *t); |
70 | enum dm_queue_mode dm_table_get_type(struct dm_table *t); |
71 | struct target_type *dm_table_get_immutable_target_type(struct dm_table *t); |
72 | struct dm_target *dm_table_get_immutable_target(struct dm_table *t); |
73 | struct dm_target *dm_table_get_wildcard_target(struct dm_table *t); |
74 | bool dm_table_bio_based(struct dm_table *t); |
75 | bool dm_table_request_based(struct dm_table *t); |
76 | |
77 | void dm_lock_md_type(struct mapped_device *md); |
78 | void dm_unlock_md_type(struct mapped_device *md); |
79 | void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type); |
80 | enum dm_queue_mode dm_get_md_type(struct mapped_device *md); |
81 | struct target_type *dm_get_immutable_target_type(struct mapped_device *md); |
82 | |
83 | int 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 | */ |
104 | int dm_set_zones_restrictions(struct dm_table *t, struct request_queue *q); |
105 | void dm_zone_endio(struct dm_io *io, struct bio *clone); |
106 | #ifdef CONFIG_BLK_DEV_ZONED |
107 | void dm_cleanup_zoned_dev(struct mapped_device *md); |
108 | int dm_blk_report_zones(struct gendisk *disk, sector_t sector, |
109 | unsigned int nr_zones, report_zones_cb cb, void *data); |
110 | bool dm_is_zone_write(struct mapped_device *md, struct bio *bio); |
111 | int dm_zone_map_bio(struct dm_target_io *io); |
112 | #else |
113 | static inline void dm_cleanup_zoned_dev(struct mapped_device *md) {} |
114 | #define dm_blk_report_zones NULL |
115 | static inline bool dm_is_zone_write(struct mapped_device *md, struct bio *bio) |
116 | { |
117 | return false; |
118 | } |
119 | static 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 | */ |
130 | int dm_target_init(void); |
131 | void dm_target_exit(void); |
132 | struct target_type *dm_get_target_type(const char *name); |
133 | void dm_put_target_type(struct target_type *tt); |
134 | int dm_target_iterate(void (*iter_func)(struct target_type *tt, |
135 | void *param), void *param); |
136 | |
137 | int dm_split_args(int *argc, char ***argvp, char *input); |
138 | |
139 | /* |
140 | * Is this mapped_device being deleted? |
141 | */ |
142 | int dm_deleting_md(struct mapped_device *md); |
143 | |
144 | /* |
145 | * Is this mapped_device suspended? |
146 | */ |
147 | int dm_suspended_md(struct mapped_device *md); |
148 | |
149 | /* |
150 | * Internal suspend and resume methods. |
151 | */ |
152 | int dm_suspended_internally_md(struct mapped_device *md); |
153 | void dm_internal_suspend_fast(struct mapped_device *md); |
154 | void dm_internal_resume_fast(struct mapped_device *md); |
155 | void dm_internal_suspend_noflush(struct mapped_device *md); |
156 | void dm_internal_resume(struct mapped_device *md); |
157 | |
158 | /* |
159 | * Test if the device is scheduled for deferred remove. |
160 | */ |
161 | int dm_test_deferred_remove_flag(struct mapped_device *md); |
162 | |
163 | /* |
164 | * Try to remove devices marked for deferred removal. |
165 | */ |
166 | void 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 | */ |
172 | int dm_interface_init(void); |
173 | void dm_interface_exit(void); |
174 | |
175 | /* |
176 | * sysfs interface |
177 | */ |
178 | int dm_sysfs_init(struct mapped_device *md); |
179 | void dm_sysfs_exit(struct mapped_device *md); |
180 | struct kobject *dm_kobject(struct mapped_device *md); |
181 | struct mapped_device *dm_get_from_kobject(struct kobject *kobj); |
182 | |
183 | /* |
184 | * The kobject helper |
185 | */ |
186 | void dm_kobject_release(struct kobject *kobj); |
187 | |
188 | /* |
189 | * Targets for linear and striped mappings |
190 | */ |
191 | int linear_map(struct dm_target *ti, struct bio *bio); |
192 | int dm_linear_init(void); |
193 | void dm_linear_exit(void); |
194 | |
195 | int stripe_map(struct dm_target *ti, struct bio *bio); |
196 | int dm_stripe_init(void); |
197 | void dm_stripe_exit(void); |
198 | |
199 | /* |
200 | * mapped_device operations |
201 | */ |
202 | void dm_destroy(struct mapped_device *md); |
203 | void dm_destroy_immediate(struct mapped_device *md); |
204 | int dm_open_count(struct mapped_device *md); |
205 | int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred); |
206 | int dm_cancel_deferred_remove(struct mapped_device *md); |
207 | int dm_request_based(struct mapped_device *md); |
208 | int dm_get_table_device(struct mapped_device *md, dev_t dev, blk_mode_t mode, |
209 | struct dm_dev **result); |
210 | void dm_put_table_device(struct mapped_device *md, struct dm_dev *d); |
211 | |
212 | int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
213 | unsigned int cookie, bool need_resize_uevent); |
214 | |
215 | int dm_io_init(void); |
216 | void dm_io_exit(void); |
217 | |
218 | int dm_kcopyd_init(void); |
219 | void dm_kcopyd_exit(void); |
220 | |
221 | /* |
222 | * Mempool operations |
223 | */ |
224 | void dm_free_md_mempools(struct dm_md_mempools *pools); |
225 | |
226 | /* |
227 | * Various helpers |
228 | */ |
229 | unsigned int dm_get_reserved_bio_based_ios(void); |
230 | |
231 | #define DM_HASH_LOCKS_MAX 64 |
232 | |
233 | static 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 | |
243 | static 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 |
253 | |