1 /* 2 * Internal header file _only_ for device mapper core 3 * 4 * Copyright (C) 2016 Red Hat, Inc. All rights reserved. 5 * 6 * This file is released under the LGPL. 7 */ 8 9 #ifndef DM_CORE_INTERNAL_H 10 #define DM_CORE_INTERNAL_H 11 12 #include <linux/kthread.h> 13 #include <linux/ktime.h> 14 #include <linux/blk-mq.h> 15 #include <linux/blk-crypto-profile.h> 16 17 #include <trace/events/block.h> 18 19 #include "dm.h" 20 #include "dm-ima.h" 21 22 #define DM_RESERVED_MAX_IOS 1024 23 24 struct dm_kobject_holder { 25 struct kobject kobj; 26 struct completion completion; 27 }; 28 29 /* 30 * DM core internal structures used directly by dm.c, dm-rq.c and dm-table.c. 31 * DM targets must _not_ deference a mapped_device or dm_table to directly 32 * access their members! 33 */ 34 35 struct mapped_device { 36 struct mutex suspend_lock; 37 38 struct mutex table_devices_lock; 39 struct list_head table_devices; 40 41 /* 42 * The current mapping (struct dm_table *). 43 * Use dm_get_live_table{_fast} or take suspend_lock for 44 * dereference. 45 */ 46 void __rcu *map; 47 48 unsigned long flags; 49 50 /* Protect queue and type against concurrent access. */ 51 struct mutex type_lock; 52 enum dm_queue_mode type; 53 54 int numa_node_id; 55 struct request_queue *queue; 56 57 atomic_t holders; 58 atomic_t open_count; 59 60 struct dm_target *immutable_target; 61 struct target_type *immutable_target_type; 62 63 char name[16]; 64 struct gendisk *disk; 65 struct dax_device *dax_dev; 66 67 wait_queue_head_t wait; 68 unsigned long __percpu *pending_io; 69 70 /* forced geometry settings */ 71 struct hd_geometry geometry; 72 73 /* 74 * Processing queue (flush) 75 */ 76 struct workqueue_struct *wq; 77 78 /* 79 * A list of ios that arrived while we were suspended. 80 */ 81 struct work_struct work; 82 spinlock_t deferred_lock; 83 struct bio_list deferred; 84 85 void *interface_ptr; 86 87 /* 88 * Event handling. 89 */ 90 wait_queue_head_t eventq; 91 atomic_t event_nr; 92 atomic_t uevent_seq; 93 struct list_head uevent_list; 94 spinlock_t uevent_lock; /* Protect access to uevent_list */ 95 96 /* for blk-mq request-based DM support */ 97 bool init_tio_pdu:1; 98 struct blk_mq_tag_set *tag_set; 99 100 struct dm_stats stats; 101 102 /* the number of internal suspends */ 103 unsigned internal_suspend_count; 104 105 int swap_bios; 106 struct semaphore swap_bios_semaphore; 107 struct mutex swap_bios_lock; 108 109 /* 110 * io objects are allocated from here. 111 */ 112 struct bio_set io_bs; 113 struct bio_set bs; 114 115 /* kobject and completion */ 116 struct dm_kobject_holder kobj_holder; 117 118 struct srcu_struct io_barrier; 119 120 #ifdef CONFIG_BLK_DEV_ZONED 121 unsigned int nr_zones; 122 unsigned int *zwp_offset; 123 #endif 124 125 #ifdef CONFIG_IMA 126 struct dm_ima_measurements ima; 127 #endif 128 }; 129 130 /* 131 * Bits for the flags field of struct mapped_device. 132 */ 133 #define DMF_BLOCK_IO_FOR_SUSPEND 0 134 #define DMF_SUSPENDED 1 135 #define DMF_FROZEN 2 136 #define DMF_FREEING 3 137 #define DMF_DELETING 4 138 #define DMF_NOFLUSH_SUSPENDING 5 139 #define DMF_DEFERRED_REMOVE 6 140 #define DMF_SUSPENDED_INTERNALLY 7 141 #define DMF_POST_SUSPENDING 8 142 #define DMF_EMULATE_ZONE_APPEND 9 143 144 void disable_discard(struct mapped_device *md); 145 void disable_write_zeroes(struct mapped_device *md); 146 147 static inline sector_t dm_get_size(struct mapped_device *md) 148 { 149 return get_capacity(md->disk); 150 } 151 152 static inline struct dm_stats *dm_get_stats(struct mapped_device *md) 153 { 154 return &md->stats; 155 } 156 157 static inline bool dm_emulate_zone_append(struct mapped_device *md) 158 { 159 if (blk_queue_is_zoned(md->queue)) 160 return test_bit(DMF_EMULATE_ZONE_APPEND, &md->flags); 161 return false; 162 } 163 164 #define DM_TABLE_MAX_DEPTH 16 165 166 struct dm_table { 167 struct mapped_device *md; 168 enum dm_queue_mode type; 169 170 /* btree table */ 171 unsigned int depth; 172 unsigned int counts[DM_TABLE_MAX_DEPTH]; /* in nodes */ 173 sector_t *index[DM_TABLE_MAX_DEPTH]; 174 175 unsigned int num_targets; 176 unsigned int num_allocated; 177 sector_t *highs; 178 struct dm_target *targets; 179 180 struct target_type *immutable_target_type; 181 182 bool integrity_supported:1; 183 bool singleton:1; 184 unsigned integrity_added:1; 185 186 /* 187 * Indicates the rw permissions for the new logical 188 * device. This should be a combination of FMODE_READ 189 * and FMODE_WRITE. 190 */ 191 fmode_t mode; 192 193 /* a list of devices used by this table */ 194 struct list_head devices; 195 196 /* events get handed up using this callback */ 197 void (*event_fn)(void *); 198 void *event_context; 199 200 struct dm_md_mempools *mempools; 201 202 #ifdef CONFIG_BLK_INLINE_ENCRYPTION 203 struct blk_crypto_profile *crypto_profile; 204 #endif 205 }; 206 207 /* 208 * One of these is allocated per clone bio. 209 */ 210 #define DM_TIO_MAGIC 28714 211 struct dm_target_io { 212 unsigned short magic; 213 blk_short_t flags; 214 unsigned int target_bio_nr; 215 struct dm_io *io; 216 struct dm_target *ti; 217 unsigned int *len_ptr; 218 sector_t old_sector; 219 struct bio clone; 220 }; 221 222 /* 223 * dm_target_io flags 224 */ 225 enum { 226 DM_TIO_INSIDE_DM_IO, 227 DM_TIO_IS_DUPLICATE_BIO 228 }; 229 230 static inline bool dm_tio_flagged(struct dm_target_io *tio, unsigned int bit) 231 { 232 return (tio->flags & (1U << bit)) != 0; 233 } 234 235 static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit) 236 { 237 tio->flags |= (1U << bit); 238 } 239 240 /* 241 * One of these is allocated per original bio. 242 * It contains the first clone used for that original. 243 */ 244 #define DM_IO_MAGIC 19577 245 struct dm_io { 246 unsigned short magic; 247 blk_short_t flags; 248 atomic_t io_count; 249 struct mapped_device *md; 250 struct bio *orig_bio; 251 blk_status_t status; 252 spinlock_t lock; 253 unsigned long start_time; 254 void *data; 255 struct hlist_node node; 256 struct task_struct *map_task; 257 struct dm_stats_aux stats_aux; 258 /* last member of dm_target_io is 'struct bio' */ 259 struct dm_target_io tio; 260 }; 261 262 /* 263 * dm_io flags 264 */ 265 enum { 266 DM_IO_START_ACCT, 267 DM_IO_ACCOUNTED 268 }; 269 270 static inline bool dm_io_flagged(struct dm_io *io, unsigned int bit) 271 { 272 return (io->flags & (1U << bit)) != 0; 273 } 274 275 static inline void dm_io_set_flag(struct dm_io *io, unsigned int bit) 276 { 277 io->flags |= (1U << bit); 278 } 279 280 static inline void dm_io_inc_pending(struct dm_io *io) 281 { 282 atomic_inc(&io->io_count); 283 } 284 285 void dm_io_dec_pending(struct dm_io *io, blk_status_t error); 286 287 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj) 288 { 289 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion; 290 } 291 292 unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max); 293 294 static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen) 295 { 296 return !maxlen || strlen(result) + 1 >= maxlen; 297 } 298 299 extern atomic_t dm_global_event_nr; 300 extern wait_queue_head_t dm_global_eventq; 301 void dm_issue_global_event(void); 302 303 #endif 304