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 #include <linux/jump_label.h> 17 18 #include <trace/events/block.h> 19 20 #include "dm.h" 21 #include "dm-ima.h" 22 23 #define DM_RESERVED_MAX_IOS 1024 24 25 struct dm_kobject_holder { 26 struct kobject kobj; 27 struct completion completion; 28 }; 29 30 /* 31 * DM core internal structures used directly by dm.c, dm-rq.c and dm-table.c. 32 * DM targets must _not_ deference a mapped_device or dm_table to directly 33 * access their members! 34 */ 35 36 /* 37 * For mempools pre-allocation at the table loading time. 38 */ 39 struct dm_md_mempools { 40 struct bio_set bs; 41 struct bio_set io_bs; 42 }; 43 44 struct mapped_device { 45 struct mutex suspend_lock; 46 47 struct mutex table_devices_lock; 48 struct list_head table_devices; 49 50 /* 51 * The current mapping (struct dm_table *). 52 * Use dm_get_live_table{_fast} or take suspend_lock for 53 * dereference. 54 */ 55 void __rcu *map; 56 57 unsigned long flags; 58 59 /* Protect queue and type against concurrent access. */ 60 struct mutex type_lock; 61 enum dm_queue_mode type; 62 63 int numa_node_id; 64 struct request_queue *queue; 65 66 atomic_t holders; 67 atomic_t open_count; 68 69 struct dm_target *immutable_target; 70 struct target_type *immutable_target_type; 71 72 char name[16]; 73 struct gendisk *disk; 74 struct dax_device *dax_dev; 75 76 wait_queue_head_t wait; 77 unsigned long __percpu *pending_io; 78 79 /* forced geometry settings */ 80 struct hd_geometry geometry; 81 82 /* 83 * Processing queue (flush) 84 */ 85 struct workqueue_struct *wq; 86 87 /* 88 * A list of ios that arrived while we were suspended. 89 */ 90 struct work_struct work; 91 spinlock_t deferred_lock; 92 struct bio_list deferred; 93 94 void *interface_ptr; 95 96 /* 97 * Event handling. 98 */ 99 wait_queue_head_t eventq; 100 atomic_t event_nr; 101 atomic_t uevent_seq; 102 struct list_head uevent_list; 103 spinlock_t uevent_lock; /* Protect access to uevent_list */ 104 105 /* for blk-mq request-based DM support */ 106 bool init_tio_pdu:1; 107 struct blk_mq_tag_set *tag_set; 108 109 struct dm_stats stats; 110 111 /* the number of internal suspends */ 112 unsigned internal_suspend_count; 113 114 int swap_bios; 115 struct semaphore swap_bios_semaphore; 116 struct mutex swap_bios_lock; 117 118 /* 119 * io objects are allocated from here. 120 */ 121 struct dm_md_mempools *mempools; 122 123 /* kobject and completion */ 124 struct dm_kobject_holder kobj_holder; 125 126 struct srcu_struct io_barrier; 127 128 #ifdef CONFIG_BLK_DEV_ZONED 129 unsigned int nr_zones; 130 unsigned int *zwp_offset; 131 #endif 132 133 #ifdef CONFIG_IMA 134 struct dm_ima_measurements ima; 135 #endif 136 }; 137 138 /* 139 * Bits for the flags field of struct mapped_device. 140 */ 141 #define DMF_BLOCK_IO_FOR_SUSPEND 0 142 #define DMF_SUSPENDED 1 143 #define DMF_FROZEN 2 144 #define DMF_FREEING 3 145 #define DMF_DELETING 4 146 #define DMF_NOFLUSH_SUSPENDING 5 147 #define DMF_DEFERRED_REMOVE 6 148 #define DMF_SUSPENDED_INTERNALLY 7 149 #define DMF_POST_SUSPENDING 8 150 #define DMF_EMULATE_ZONE_APPEND 9 151 152 void disable_discard(struct mapped_device *md); 153 void disable_write_zeroes(struct mapped_device *md); 154 155 static inline sector_t dm_get_size(struct mapped_device *md) 156 { 157 return get_capacity(md->disk); 158 } 159 160 static inline struct dm_stats *dm_get_stats(struct mapped_device *md) 161 { 162 return &md->stats; 163 } 164 165 DECLARE_STATIC_KEY_FALSE(stats_enabled); 166 DECLARE_STATIC_KEY_FALSE(swap_bios_enabled); 167 DECLARE_STATIC_KEY_FALSE(zoned_enabled); 168 169 static inline bool dm_emulate_zone_append(struct mapped_device *md) 170 { 171 if (blk_queue_is_zoned(md->queue)) 172 return test_bit(DMF_EMULATE_ZONE_APPEND, &md->flags); 173 return false; 174 } 175 176 #define DM_TABLE_MAX_DEPTH 16 177 178 struct dm_table { 179 struct mapped_device *md; 180 enum dm_queue_mode type; 181 182 /* btree table */ 183 unsigned int depth; 184 unsigned int counts[DM_TABLE_MAX_DEPTH]; /* in nodes */ 185 sector_t *index[DM_TABLE_MAX_DEPTH]; 186 187 unsigned int num_targets; 188 unsigned int num_allocated; 189 sector_t *highs; 190 struct dm_target *targets; 191 192 struct target_type *immutable_target_type; 193 194 bool integrity_supported:1; 195 bool singleton:1; 196 unsigned integrity_added:1; 197 198 /* 199 * Indicates the rw permissions for the new logical 200 * device. This should be a combination of FMODE_READ 201 * and FMODE_WRITE. 202 */ 203 fmode_t mode; 204 205 /* a list of devices used by this table */ 206 struct list_head devices; 207 208 /* events get handed up using this callback */ 209 void (*event_fn)(void *); 210 void *event_context; 211 212 struct dm_md_mempools *mempools; 213 214 #ifdef CONFIG_BLK_INLINE_ENCRYPTION 215 struct blk_crypto_profile *crypto_profile; 216 #endif 217 }; 218 219 /* 220 * One of these is allocated per clone bio. 221 */ 222 #define DM_TIO_MAGIC 28714 223 struct dm_target_io { 224 unsigned short magic; 225 blk_short_t flags; 226 unsigned int target_bio_nr; 227 struct dm_io *io; 228 struct dm_target *ti; 229 unsigned int *len_ptr; 230 sector_t old_sector; 231 struct bio clone; 232 }; 233 234 /* 235 * dm_target_io flags 236 */ 237 enum { 238 DM_TIO_INSIDE_DM_IO, 239 DM_TIO_IS_DUPLICATE_BIO 240 }; 241 242 static inline bool dm_tio_flagged(struct dm_target_io *tio, unsigned int bit) 243 { 244 return (tio->flags & (1U << bit)) != 0; 245 } 246 247 static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit) 248 { 249 tio->flags |= (1U << bit); 250 } 251 252 static inline bool dm_tio_is_normal(struct dm_target_io *tio) 253 { 254 return (dm_tio_flagged(tio, DM_TIO_INSIDE_DM_IO) && 255 !dm_tio_flagged(tio, DM_TIO_IS_DUPLICATE_BIO)); 256 } 257 258 /* 259 * One of these is allocated per original bio. 260 * It contains the first clone used for that original. 261 */ 262 #define DM_IO_MAGIC 19577 263 struct dm_io { 264 unsigned short magic; 265 blk_short_t flags; 266 spinlock_t lock; 267 unsigned long start_time; 268 void *data; 269 struct dm_io *next; 270 struct dm_stats_aux stats_aux; 271 blk_status_t status; 272 atomic_t io_count; 273 struct mapped_device *md; 274 275 /* The three fields represent mapped part of original bio */ 276 struct bio *orig_bio; 277 unsigned int sector_offset; /* offset to end of orig_bio */ 278 unsigned int sectors; 279 280 /* last member of dm_target_io is 'struct bio' */ 281 struct dm_target_io tio; 282 }; 283 284 /* 285 * dm_io flags 286 */ 287 enum { 288 DM_IO_ACCOUNTED, 289 DM_IO_WAS_SPLIT 290 }; 291 292 static inline bool dm_io_flagged(struct dm_io *io, unsigned int bit) 293 { 294 return (io->flags & (1U << bit)) != 0; 295 } 296 297 static inline void dm_io_set_flag(struct dm_io *io, unsigned int bit) 298 { 299 io->flags |= (1U << bit); 300 } 301 302 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj) 303 { 304 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion; 305 } 306 307 unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max); 308 309 static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen) 310 { 311 return !maxlen || strlen(result) + 1 >= maxlen; 312 } 313 314 extern atomic_t dm_global_event_nr; 315 extern wait_queue_head_t dm_global_eventq; 316 void dm_issue_global_event(void); 317 318 #endif 319