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 /* 68 * A list of ios that arrived while we were suspended. 69 */ 70 struct work_struct work; 71 wait_queue_head_t wait; 72 spinlock_t deferred_lock; 73 struct bio_list deferred; 74 75 void *interface_ptr; 76 77 /* 78 * Event handling. 79 */ 80 wait_queue_head_t eventq; 81 atomic_t event_nr; 82 atomic_t uevent_seq; 83 struct list_head uevent_list; 84 spinlock_t uevent_lock; /* Protect access to uevent_list */ 85 86 /* the number of internal suspends */ 87 unsigned internal_suspend_count; 88 89 /* 90 * io objects are allocated from here. 91 */ 92 struct bio_set io_bs; 93 struct bio_set bs; 94 95 /* 96 * Processing queue (flush) 97 */ 98 struct workqueue_struct *wq; 99 100 /* forced geometry settings */ 101 struct hd_geometry geometry; 102 103 /* kobject and completion */ 104 struct dm_kobject_holder kobj_holder; 105 106 int swap_bios; 107 struct semaphore swap_bios_semaphore; 108 struct mutex swap_bios_lock; 109 110 struct dm_stats stats; 111 112 /* for blk-mq request-based DM support */ 113 struct blk_mq_tag_set *tag_set; 114 bool init_tio_pdu:1; 115 116 struct srcu_struct io_barrier; 117 118 #ifdef CONFIG_BLK_DEV_ZONED 119 unsigned int nr_zones; 120 unsigned int *zwp_offset; 121 #endif 122 123 #ifdef CONFIG_IMA 124 struct dm_ima_measurements ima; 125 #endif 126 }; 127 128 /* 129 * Bits for the flags field of struct mapped_device. 130 */ 131 #define DMF_BLOCK_IO_FOR_SUSPEND 0 132 #define DMF_SUSPENDED 1 133 #define DMF_FROZEN 2 134 #define DMF_FREEING 3 135 #define DMF_DELETING 4 136 #define DMF_NOFLUSH_SUSPENDING 5 137 #define DMF_DEFERRED_REMOVE 6 138 #define DMF_SUSPENDED_INTERNALLY 7 139 #define DMF_POST_SUSPENDING 8 140 #define DMF_EMULATE_ZONE_APPEND 9 141 142 void disable_discard(struct mapped_device *md); 143 void disable_write_same(struct mapped_device *md); 144 void disable_write_zeroes(struct mapped_device *md); 145 146 static inline sector_t dm_get_size(struct mapped_device *md) 147 { 148 return get_capacity(md->disk); 149 } 150 151 static inline struct dm_stats *dm_get_stats(struct mapped_device *md) 152 { 153 return &md->stats; 154 } 155 156 static inline bool dm_emulate_zone_append(struct mapped_device *md) 157 { 158 if (blk_queue_is_zoned(md->queue)) 159 return test_bit(DMF_EMULATE_ZONE_APPEND, &md->flags); 160 return false; 161 } 162 163 #define DM_TABLE_MAX_DEPTH 16 164 165 struct dm_table { 166 struct mapped_device *md; 167 enum dm_queue_mode type; 168 169 /* btree table */ 170 unsigned int depth; 171 unsigned int counts[DM_TABLE_MAX_DEPTH]; /* in nodes */ 172 sector_t *index[DM_TABLE_MAX_DEPTH]; 173 174 unsigned int num_targets; 175 unsigned int num_allocated; 176 sector_t *highs; 177 struct dm_target *targets; 178 179 struct target_type *immutable_target_type; 180 181 bool integrity_supported:1; 182 bool singleton:1; 183 unsigned integrity_added:1; 184 185 /* 186 * Indicates the rw permissions for the new logical 187 * device. This should be a combination of FMODE_READ 188 * and FMODE_WRITE. 189 */ 190 fmode_t mode; 191 192 /* a list of devices used by this table */ 193 struct list_head devices; 194 195 /* events get handed up using this callback */ 196 void (*event_fn)(void *); 197 void *event_context; 198 199 struct dm_md_mempools *mempools; 200 201 #ifdef CONFIG_BLK_INLINE_ENCRYPTION 202 struct blk_crypto_profile *crypto_profile; 203 #endif 204 }; 205 206 /* 207 * One of these is allocated per clone bio. 208 */ 209 #define DM_TIO_MAGIC 7282014 210 struct dm_target_io { 211 unsigned int magic; 212 struct dm_io *io; 213 struct dm_target *ti; 214 unsigned int target_bio_nr; 215 unsigned int *len_ptr; 216 bool inside_dm_io; 217 struct bio clone; 218 }; 219 220 /* 221 * One of these is allocated per original bio. 222 * It contains the first clone used for that original. 223 */ 224 #define DM_IO_MAGIC 5191977 225 struct dm_io { 226 unsigned int magic; 227 struct mapped_device *md; 228 blk_status_t status; 229 atomic_t io_count; 230 struct bio *orig_bio; 231 unsigned long start_time; 232 spinlock_t endio_lock; 233 struct dm_stats_aux stats_aux; 234 /* last member of dm_target_io is 'struct bio' */ 235 struct dm_target_io tio; 236 }; 237 238 static inline void dm_io_inc_pending(struct dm_io *io) 239 { 240 atomic_inc(&io->io_count); 241 } 242 243 void dm_io_dec_pending(struct dm_io *io, blk_status_t error); 244 245 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj) 246 { 247 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion; 248 } 249 250 unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max); 251 252 static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen) 253 { 254 return !maxlen || strlen(result) + 1 >= maxlen; 255 } 256 257 extern atomic_t dm_global_event_nr; 258 extern wait_queue_head_t dm_global_eventq; 259 void dm_issue_global_event(void); 260 261 #endif 262