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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * Internal header file _only_ for device mapper core4 *5 * Copyright (C) 2016 Red Hat, Inc. All rights reserved.6 *7 * This file is released under the LGPL.8 */9 10#ifndef DM_CORE_INTERNAL_H11#define DM_CORE_INTERNAL_H12 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>18 19#include <trace/events/block.h>20 21#include "dm.h"22#include "dm-ima.h"23 24#define DM_RESERVED_MAX_IOS 102425#define DM_MAX_TARGETS 104857626#define DM_MAX_TARGET_PARAMS 102427 28struct dm_io;29 30struct dm_kobject_holder {31 struct kobject kobj;32 struct completion completion;33};34 35/*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 directly38 * access their members!39 */40 41/*42 * For mempools pre-allocation at the table loading time.43 */44struct dm_md_mempools {45 struct bio_set bs;46 struct bio_set io_bs;47};48 49struct mapped_device {50 struct mutex suspend_lock;51 52 struct mutex table_devices_lock;53 struct list_head table_devices;54 55 /*56 * The current mapping (struct dm_table *).57 * Use dm_get_live_table{_fast} or take suspend_lock for58 * dereference.59 */60 void __rcu *map;61 62 unsigned long flags;63 64 /* Protect queue and type against concurrent access. */65 struct mutex type_lock;66 enum dm_queue_mode type;67 68 int numa_node_id;69 struct request_queue *queue;70 71 atomic_t holders;72 atomic_t open_count;73 74 struct dm_target *immutable_target;75 struct target_type *immutable_target_type;76 77 char name[16];78 struct gendisk *disk;79 struct dax_device *dax_dev;80 81 wait_queue_head_t wait;82 unsigned long __percpu *pending_io;83 84 /* forced geometry settings */85 struct hd_geometry geometry;86 87 /*88 * Processing queue (flush)89 */90 struct workqueue_struct *wq;91 92 /*93 * A list of ios that arrived while we were suspended.94 */95 struct work_struct work;96 spinlock_t deferred_lock;97 struct bio_list deferred;98 99 /*100 * requeue work context is needed for cloning one new bio101 * to represent the dm_io to be requeued, since each102 * dm_io may point to the original bio from FS.103 */104 struct work_struct requeue_work;105 struct dm_io *requeue_list;106 107 void *interface_ptr;108 109 /*110 * Event handling.111 */112 wait_queue_head_t eventq;113 atomic_t event_nr;114 atomic_t uevent_seq;115 struct list_head uevent_list;116 spinlock_t uevent_lock; /* Protect access to uevent_list */117 118 /* for blk-mq request-based DM support */119 bool init_tio_pdu:1;120 struct blk_mq_tag_set *tag_set;121 122 struct dm_stats stats;123 124 /* the number of internal suspends */125 unsigned int internal_suspend_count;126 127 int swap_bios;128 struct semaphore swap_bios_semaphore;129 struct mutex swap_bios_lock;130 131 /*132 * io objects are allocated from here.133 */134 struct dm_md_mempools *mempools;135 136 /* kobject and completion */137 struct dm_kobject_holder kobj_holder;138 139 struct srcu_struct io_barrier;140 141#ifdef CONFIG_BLK_DEV_ZONED142 unsigned int nr_zones;143 void *zone_revalidate_map;144#endif145 146#ifdef CONFIG_IMA147 struct dm_ima_measurements ima;148#endif149};150 151/*152 * Bits for the flags field of struct mapped_device.153 */154#define DMF_BLOCK_IO_FOR_SUSPEND 0155#define DMF_SUSPENDED 1156#define DMF_FROZEN 2157#define DMF_FREEING 3158#define DMF_DELETING 4159#define DMF_NOFLUSH_SUSPENDING 5160#define DMF_DEFERRED_REMOVE 6161#define DMF_SUSPENDED_INTERNALLY 7162#define DMF_POST_SUSPENDING 8163#define DMF_EMULATE_ZONE_APPEND 9164 165void disable_discard(struct mapped_device *md);166void disable_write_zeroes(struct mapped_device *md);167 168static inline sector_t dm_get_size(struct mapped_device *md)169{170 return get_capacity(md->disk);171}172 173static inline struct dm_stats *dm_get_stats(struct mapped_device *md)174{175 return &md->stats;176}177 178DECLARE_STATIC_KEY_FALSE(stats_enabled);179DECLARE_STATIC_KEY_FALSE(swap_bios_enabled);180DECLARE_STATIC_KEY_FALSE(zoned_enabled);181 182static inline bool dm_emulate_zone_append(struct mapped_device *md)183{184 if (blk_queue_is_zoned(md->queue))185 return test_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);186 return false;187}188 189#define DM_TABLE_MAX_DEPTH 16190 191struct dm_table {192 struct mapped_device *md;193 enum dm_queue_mode type;194 195 /* btree table */196 unsigned int depth;197 unsigned int counts[DM_TABLE_MAX_DEPTH]; /* in nodes */198 sector_t *index[DM_TABLE_MAX_DEPTH];199 200 unsigned int num_targets;201 unsigned int num_allocated;202 sector_t *highs;203 struct dm_target *targets;204 205 struct target_type *immutable_target_type;206 207 bool integrity_supported:1;208 bool singleton:1;209 /* set if all the targets in the table have "flush_bypasses_map" set */210 bool flush_bypasses_map:1;211 212 /*213 * Indicates the rw permissions for the new logical device. This214 * should be a combination of BLK_OPEN_READ and BLK_OPEN_WRITE.215 */216 blk_mode_t mode;217 218 /* a list of devices used by this table */219 struct list_head devices;220 struct rw_semaphore devices_lock;221 222 /* events get handed up using this callback */223 void (*event_fn)(void *data);224 void *event_context;225 226 struct dm_md_mempools *mempools;227 228#ifdef CONFIG_BLK_INLINE_ENCRYPTION229 struct blk_crypto_profile *crypto_profile;230#endif231};232 233static inline struct dm_target *dm_table_get_target(struct dm_table *t,234 unsigned int index)235{236 BUG_ON(index >= t->num_targets);237 return t->targets + index;238}239 240/*241 * One of these is allocated per clone bio.242 */243#define DM_TIO_MAGIC 28714244struct dm_target_io {245 unsigned short magic;246 blk_short_t flags;247 unsigned int target_bio_nr;248 struct dm_io *io;249 struct dm_target *ti;250 unsigned int *len_ptr;251 sector_t old_sector;252 struct bio clone;253};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))257 258/*259 * dm_target_io flags260 */261enum {262 DM_TIO_INSIDE_DM_IO,263 DM_TIO_IS_DUPLICATE_BIO264};265 266static inline bool dm_tio_flagged(struct dm_target_io *tio, unsigned int bit)267{268 return (tio->flags & (1U << bit)) != 0;269}270 271static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit)272{273 tio->flags |= (1U << bit);274}275 276static inline bool dm_tio_is_normal(struct dm_target_io *tio)277{278 return (dm_tio_flagged(tio, DM_TIO_INSIDE_DM_IO) &&279 !dm_tio_flagged(tio, DM_TIO_IS_DUPLICATE_BIO));280}281 282/*283 * One of these is allocated per original bio.284 * It contains the first clone used for that original.285 */286#define DM_IO_MAGIC 19577287struct dm_io {288 unsigned short magic;289 blk_short_t flags;290 spinlock_t lock;291 unsigned long start_time;292 void *data;293 struct dm_io *next;294 struct dm_stats_aux stats_aux;295 blk_status_t status;296 atomic_t io_count;297 struct mapped_device *md;298 299 /* 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;303 304 /* last member of dm_target_io is 'struct bio' */305 struct dm_target_io tio;306};307 308/*309 * dm_io flags310 */311enum {312 DM_IO_ACCOUNTED,313 DM_IO_WAS_SPLIT,314 DM_IO_BLK_STAT315};316 317static inline bool dm_io_flagged(struct dm_io *io, unsigned int bit)318{319 return (io->flags & (1U << bit)) != 0;320}321 322static inline void dm_io_set_flag(struct dm_io *io, unsigned int bit)323{324 io->flags |= (1U << bit);325}326 327void dm_io_rewind(struct dm_io *io, struct bio_set *bs);328 329static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)330{331 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;332}333 334unsigned int __dm_get_module_param(unsigned int *module_param, unsigned int def, unsigned int max);335 336static inline bool dm_message_test_buffer_overflow(char *result, unsigned int maxlen)337{338 return !maxlen || strlen(result) + 1 >= maxlen;339}340 341extern atomic_t dm_global_event_nr;342extern wait_queue_head_t dm_global_eventq;343void dm_issue_global_event(void);344 345#endif346