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/genhd.h> 15 #include <linux/blk-mq.h> 16 #include <linux/keyslot-manager.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 struct mapped_device { 37 struct mutex suspend_lock; 38 39 struct mutex table_devices_lock; 40 struct list_head table_devices; 41 42 /* 43 * The current mapping (struct dm_table *). 44 * Use dm_get_live_table{_fast} or take suspend_lock for 45 * dereference. 46 */ 47 void __rcu *map; 48 49 unsigned long flags; 50 51 /* Protect queue and type against concurrent access. */ 52 struct mutex type_lock; 53 enum dm_queue_mode type; 54 55 int numa_node_id; 56 struct request_queue *queue; 57 58 atomic_t holders; 59 atomic_t open_count; 60 61 struct dm_target *immutable_target; 62 struct target_type *immutable_target_type; 63 64 char name[16]; 65 struct gendisk *disk; 66 struct dax_device *dax_dev; 67 68 /* 69 * A list of ios that arrived while we were suspended. 70 */ 71 struct work_struct work; 72 wait_queue_head_t wait; 73 spinlock_t deferred_lock; 74 struct bio_list deferred; 75 76 void *interface_ptr; 77 78 /* 79 * Event handling. 80 */ 81 wait_queue_head_t eventq; 82 atomic_t event_nr; 83 atomic_t uevent_seq; 84 struct list_head uevent_list; 85 spinlock_t uevent_lock; /* Protect access to uevent_list */ 86 87 /* the number of internal suspends */ 88 unsigned internal_suspend_count; 89 90 /* 91 * io objects are allocated from here. 92 */ 93 struct bio_set io_bs; 94 struct bio_set bs; 95 96 /* 97 * Processing queue (flush) 98 */ 99 struct workqueue_struct *wq; 100 101 /* forced geometry settings */ 102 struct hd_geometry geometry; 103 104 /* kobject and completion */ 105 struct dm_kobject_holder kobj_holder; 106 107 int swap_bios; 108 struct semaphore swap_bios_semaphore; 109 struct mutex swap_bios_lock; 110 111 struct dm_stats stats; 112 113 /* for blk-mq request-based DM support */ 114 struct blk_mq_tag_set *tag_set; 115 bool init_tio_pdu:1; 116 117 struct srcu_struct io_barrier; 118 119 #ifdef CONFIG_BLK_DEV_ZONED 120 unsigned int nr_zones; 121 unsigned int *zwp_offset; 122 #endif 123 124 #ifdef CONFIG_IMA 125 struct dm_ima_measurements ima; 126 #endif 127 }; 128 129 /* 130 * Bits for the flags field of struct mapped_device. 131 */ 132 #define DMF_BLOCK_IO_FOR_SUSPEND 0 133 #define DMF_SUSPENDED 1 134 #define DMF_FROZEN 2 135 #define DMF_FREEING 3 136 #define DMF_DELETING 4 137 #define DMF_NOFLUSH_SUSPENDING 5 138 #define DMF_DEFERRED_REMOVE 6 139 #define DMF_SUSPENDED_INTERNALLY 7 140 #define DMF_POST_SUSPENDING 8 141 #define DMF_EMULATE_ZONE_APPEND 9 142 143 void disable_discard(struct mapped_device *md); 144 void disable_write_same(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_keyslot_manager *ksm; 204 #endif 205 }; 206 207 /* 208 * One of these is allocated per clone bio. 209 */ 210 #define DM_TIO_MAGIC 7282014 211 struct dm_target_io { 212 unsigned int magic; 213 struct dm_io *io; 214 struct dm_target *ti; 215 unsigned int target_bio_nr; 216 unsigned int *len_ptr; 217 bool inside_dm_io; 218 struct bio clone; 219 }; 220 221 /* 222 * One of these is allocated per original bio. 223 * It contains the first clone used for that original. 224 */ 225 #define DM_IO_MAGIC 5191977 226 struct dm_io { 227 unsigned int magic; 228 struct mapped_device *md; 229 blk_status_t status; 230 atomic_t io_count; 231 struct bio *orig_bio; 232 unsigned long start_time; 233 spinlock_t endio_lock; 234 struct dm_stats_aux stats_aux; 235 /* last member of dm_target_io is 'struct bio' */ 236 struct dm_target_io tio; 237 }; 238 239 static inline void dm_io_inc_pending(struct dm_io *io) 240 { 241 atomic_inc(&io->io_count); 242 } 243 244 void dm_io_dec_pending(struct dm_io *io, blk_status_t error); 245 246 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj) 247 { 248 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion; 249 } 250 251 unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max); 252 253 static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen) 254 { 255 return !maxlen || strlen(result) + 1 >= maxlen; 256 } 257 258 extern atomic_t dm_global_event_nr; 259 extern wait_queue_head_t dm_global_eventq; 260 void dm_issue_global_event(void); 261 262 #endif 263