1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Internal header file _only_ for device mapper core
5 * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
7 * This file is released under the LGPL.
10 #ifndef DM_CORE_INTERNAL_H
11 #define DM_CORE_INTERNAL_H
13 #include <linux/kthread.h>
14 #include <linux/ktime.h>
15 #include <linux/blk-mq.h>
16 #include <linux/blk-crypto-profile.h>
17 #include <linux/jump_label.h>
19 #include <trace/events/block.h>
24 #define DM_RESERVED_MAX_IOS 1024
25 #define DM_MAX_TARGETS 1048576
26 #define DM_MAX_TARGET_PARAMS 1024
30 struct dm_kobject_holder {
32 struct completion completion;
36 * DM core internal structures used directly by dm.c, dm-rq.c and dm-table.c.
37 * DM targets must _not_ deference a mapped_device or dm_table to directly
38 * access their members!
42 * For mempools pre-allocation at the table loading time.
44 struct dm_md_mempools {
49 struct mapped_device {
50 struct mutex suspend_lock;
52 struct mutex table_devices_lock;
53 struct list_head table_devices;
56 * The current mapping (struct dm_table *).
57 * Use dm_get_live_table{_fast} or take suspend_lock for
64 /* Protect queue and type against concurrent access. */
65 struct mutex type_lock;
66 enum dm_queue_mode type;
69 struct request_queue *queue;
74 struct dm_target *immutable_target;
75 struct target_type *immutable_target_type;
79 struct dax_device *dax_dev;
81 wait_queue_head_t wait;
82 unsigned long __percpu *pending_io;
84 /* forced geometry settings */
85 struct hd_geometry geometry;
88 * Processing queue (flush)
90 struct workqueue_struct *wq;
93 * A list of ios that arrived while we were suspended.
95 struct work_struct work;
96 spinlock_t deferred_lock;
97 struct bio_list deferred;
100 * requeue work context is needed for cloning one new bio
101 * to represent the dm_io to be requeued, since each
102 * dm_io may point to the original bio from FS.
104 struct work_struct requeue_work;
105 struct dm_io *requeue_list;
112 wait_queue_head_t eventq;
115 struct list_head uevent_list;
116 spinlock_t uevent_lock; /* Protect access to uevent_list */
118 /* for blk-mq request-based DM support */
120 struct blk_mq_tag_set *tag_set;
122 struct dm_stats stats;
124 /* the number of internal suspends */
125 unsigned int internal_suspend_count;
128 struct semaphore swap_bios_semaphore;
129 struct mutex swap_bios_lock;
132 * io objects are allocated from here.
134 struct dm_md_mempools *mempools;
136 /* kobject and completion */
137 struct dm_kobject_holder kobj_holder;
139 struct srcu_struct io_barrier;
141 #ifdef CONFIG_BLK_DEV_ZONED
142 unsigned int nr_zones;
143 void *zone_revalidate_map;
147 struct dm_ima_measurements ima;
152 * Bits for the flags field of struct mapped_device.
154 #define DMF_BLOCK_IO_FOR_SUSPEND 0
155 #define DMF_SUSPENDED 1
157 #define DMF_FREEING 3
158 #define DMF_DELETING 4
159 #define DMF_NOFLUSH_SUSPENDING 5
160 #define DMF_DEFERRED_REMOVE 6
161 #define DMF_SUSPENDED_INTERNALLY 7
162 #define DMF_POST_SUSPENDING 8
163 #define DMF_EMULATE_ZONE_APPEND 9
165 void disable_discard(struct mapped_device *md);
166 void disable_write_zeroes(struct mapped_device *md);
168 static inline sector_t dm_get_size(struct mapped_device *md)
170 return get_capacity(md->disk);
173 static inline struct dm_stats *dm_get_stats(struct mapped_device *md)
178 DECLARE_STATIC_KEY_FALSE(stats_enabled);
179 DECLARE_STATIC_KEY_FALSE(swap_bios_enabled);
180 DECLARE_STATIC_KEY_FALSE(zoned_enabled);
182 static inline bool dm_emulate_zone_append(struct mapped_device *md)
184 if (blk_queue_is_zoned(md->queue))
185 return test_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);
189 #define DM_TABLE_MAX_DEPTH 16
192 struct mapped_device *md;
193 enum dm_queue_mode type;
197 unsigned int counts[DM_TABLE_MAX_DEPTH]; /* in nodes */
198 sector_t *index[DM_TABLE_MAX_DEPTH];
200 unsigned int num_targets;
201 unsigned int num_allocated;
203 struct dm_target *targets;
205 struct target_type *immutable_target_type;
207 bool integrity_supported:1;
209 /* set if all the targets in the table have "flush_bypasses_map" set */
210 bool flush_bypasses_map:1;
213 * Indicates the rw permissions for the new logical device. This
214 * should be a combination of BLK_OPEN_READ and BLK_OPEN_WRITE.
218 /* a list of devices used by this table */
219 struct list_head devices;
220 struct rw_semaphore devices_lock;
222 /* events get handed up using this callback */
223 void (*event_fn)(void *data);
226 struct dm_md_mempools *mempools;
228 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
229 struct blk_crypto_profile *crypto_profile;
233 static inline struct dm_target *dm_table_get_target(struct dm_table *t,
236 BUG_ON(index >= t->num_targets);
237 return t->targets + index;
241 * One of these is allocated per clone bio.
243 #define DM_TIO_MAGIC 28714
244 struct dm_target_io {
245 unsigned short magic;
247 unsigned int target_bio_nr;
249 struct dm_target *ti;
250 unsigned int *len_ptr;
254 #define DM_TARGET_IO_BIO_OFFSET (offsetof(struct dm_target_io, clone))
255 #define DM_IO_BIO_OFFSET \
256 (offsetof(struct dm_target_io, clone) + offsetof(struct dm_io, tio))
263 DM_TIO_IS_DUPLICATE_BIO
266 static inline bool dm_tio_flagged(struct dm_target_io *tio, unsigned int bit)
268 return (tio->flags & (1U << bit)) != 0;
271 static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit)
273 tio->flags |= (1U << bit);
276 static inline bool dm_tio_is_normal(struct dm_target_io *tio)
278 return (dm_tio_flagged(tio, DM_TIO_INSIDE_DM_IO) &&
279 !dm_tio_flagged(tio, DM_TIO_IS_DUPLICATE_BIO));
283 * One of these is allocated per original bio.
284 * It contains the first clone used for that original.
286 #define DM_IO_MAGIC 19577
288 unsigned short magic;
291 unsigned long start_time;
294 struct dm_stats_aux stats_aux;
297 struct mapped_device *md;
299 /* The three fields represent mapped part of original bio */
300 struct bio *orig_bio;
301 unsigned int sector_offset; /* offset to end of orig_bio */
302 unsigned int sectors;
304 /* last member of dm_target_io is 'struct bio' */
305 struct dm_target_io tio;
317 static inline bool dm_io_flagged(struct dm_io *io, unsigned int bit)
319 return (io->flags & (1U << bit)) != 0;
322 static inline void dm_io_set_flag(struct dm_io *io, unsigned int bit)
324 io->flags |= (1U << bit);
327 void dm_io_rewind(struct dm_io *io, struct bio_set *bs);
329 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
331 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
334 unsigned int __dm_get_module_param(unsigned int *module_param, unsigned int def, unsigned int max);
336 static inline bool dm_message_test_buffer_overflow(char *result, unsigned int maxlen)
338 return !maxlen || strlen(result) + 1 >= maxlen;
341 extern atomic_t dm_global_event_nr;
342 extern wait_queue_head_t dm_global_eventq;
343 void dm_issue_global_event(void);