1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef BTRFS_BLOCK_GROUP_H 4 #define BTRFS_BLOCK_GROUP_H 5 6 #include <linux/atomic.h> 7 #include <linux/mutex.h> 8 #include <linux/list.h> 9 #include <linux/spinlock.h> 10 #include <linux/refcount.h> 11 #include <linux/wait.h> 12 #include <linux/sizes.h> 13 #include <linux/rwsem.h> 14 #include <linux/rbtree.h> 15 #include <uapi/linux/btrfs_tree.h> 16 #include "free-space-cache.h" 17 18 struct btrfs_chunk_map; 19 struct btrfs_fs_info; 20 struct btrfs_inode; 21 struct btrfs_trans_handle; 22 23 enum btrfs_disk_cache_state { 24 BTRFS_DC_WRITTEN, 25 BTRFS_DC_ERROR, 26 BTRFS_DC_CLEAR, 27 BTRFS_DC_SETUP, 28 }; 29 30 enum btrfs_block_group_size_class { 31 /* Unset */ 32 BTRFS_BG_SZ_NONE, 33 /* 0 < size <= 128K */ 34 BTRFS_BG_SZ_SMALL, 35 /* 128K < size <= 8M */ 36 BTRFS_BG_SZ_MEDIUM, 37 /* 8M < size < BG_LENGTH */ 38 BTRFS_BG_SZ_LARGE, 39 }; 40 41 /* 42 * This describes the state of the block_group for async discard. This is due 43 * to the two pass nature of it where extent discarding is prioritized over 44 * bitmap discarding. BTRFS_DISCARD_RESET_CURSOR is set when we are resetting 45 * between lists to prevent contention for discard state variables 46 * (eg. discard_cursor). 47 */ 48 enum btrfs_discard_state { 49 BTRFS_DISCARD_EXTENTS, 50 BTRFS_DISCARD_BITMAPS, 51 BTRFS_DISCARD_RESET_CURSOR, 52 }; 53 54 /* 55 * Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to 56 * only allocate a chunk if we really need one. 57 * 58 * CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few 59 * chunks already allocated. This is used as part of the clustering code to 60 * help make sure we have a good pool of storage to cluster in, without filling 61 * the FS with empty chunks 62 * 63 * CHUNK_ALLOC_FORCE means it must try to allocate one 64 * 65 * CHUNK_ALLOC_FORCE_FOR_EXTENT like CHUNK_ALLOC_FORCE but called from 66 * find_free_extent() that also activaes the zone 67 */ 68 enum btrfs_chunk_alloc_enum { 69 CHUNK_ALLOC_NO_FORCE, 70 CHUNK_ALLOC_LIMITED, 71 CHUNK_ALLOC_FORCE, 72 CHUNK_ALLOC_FORCE_FOR_EXTENT, 73 }; 74 75 /* Block group flags set at runtime */ 76 enum btrfs_block_group_flags { 77 BLOCK_GROUP_FLAG_IREF, 78 BLOCK_GROUP_FLAG_REMOVED, 79 BLOCK_GROUP_FLAG_TO_COPY, 80 BLOCK_GROUP_FLAG_RELOCATING_REPAIR, 81 BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED, 82 BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE, 83 BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, 84 /* Does the block group need to be added to the free space tree? */ 85 BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, 86 /* Set after we add a new block group to the free space tree. */ 87 BLOCK_GROUP_FLAG_FREE_SPACE_ADDED, 88 /* Indicate that the block group is placed on a sequential zone */ 89 BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE, 90 /* 91 * Indicate that block group is in the list of new block groups of a 92 * transaction. 93 */ 94 BLOCK_GROUP_FLAG_NEW, 95 }; 96 97 enum btrfs_caching_type { 98 BTRFS_CACHE_NO, 99 BTRFS_CACHE_STARTED, 100 BTRFS_CACHE_FINISHED, 101 BTRFS_CACHE_ERROR, 102 }; 103 104 struct btrfs_caching_control { 105 struct list_head list; 106 struct mutex mutex; 107 wait_queue_head_t wait; 108 struct btrfs_work work; 109 struct btrfs_block_group *block_group; 110 /* Track progress of caching during allocation. */ 111 atomic_t progress; 112 refcount_t count; 113 }; 114 115 /* Once caching_thread() finds this much free space, it will wake up waiters. */ 116 #define CACHING_CTL_WAKE_UP SZ_2M 117 118 struct btrfs_block_group { 119 struct btrfs_fs_info *fs_info; 120 struct btrfs_inode *inode; 121 spinlock_t lock; 122 u64 start; 123 u64 length; 124 u64 pinned; 125 u64 reserved; 126 u64 used; 127 u64 delalloc_bytes; 128 u64 bytes_super; 129 u64 flags; 130 u64 cache_generation; 131 u64 global_root_id; 132 133 /* 134 * The last committed used bytes of this block group, if the above @used 135 * is still the same as @commit_used, we don't need to update block 136 * group item of this block group. 137 */ 138 u64 commit_used; 139 /* 140 * If the free space extent count exceeds this number, convert the block 141 * group to bitmaps. 142 */ 143 u32 bitmap_high_thresh; 144 145 /* 146 * If the free space extent count drops below this number, convert the 147 * block group back to extents. 148 */ 149 u32 bitmap_low_thresh; 150 151 /* 152 * It is just used for the delayed data space allocation because 153 * only the data space allocation and the relative metadata update 154 * can be done cross the transaction. 155 */ 156 struct rw_semaphore data_rwsem; 157 158 /* For raid56, this is a full stripe, without parity */ 159 unsigned long full_stripe_len; 160 unsigned long runtime_flags; 161 162 unsigned int ro; 163 164 int disk_cache_state; 165 166 /* Cache tracking stuff */ 167 int cached; 168 struct btrfs_caching_control *caching_ctl; 169 170 struct btrfs_space_info *space_info; 171 172 /* Free space cache stuff */ 173 struct btrfs_free_space_ctl *free_space_ctl; 174 175 /* Block group cache stuff */ 176 struct rb_node cache_node; 177 178 /* For block groups in the same raid type */ 179 struct list_head list; 180 181 refcount_t refs; 182 183 /* 184 * List of struct btrfs_free_clusters for this block group. 185 * Today it will only have one thing on it, but that may change 186 */ 187 struct list_head cluster_list; 188 189 /* 190 * Used for several lists: 191 * 192 * 1) struct btrfs_fs_info::unused_bgs 193 * 2) struct btrfs_fs_info::reclaim_bgs 194 * 3) struct btrfs_transaction::deleted_bgs 195 * 4) struct btrfs_trans_handle::new_bgs 196 */ 197 struct list_head bg_list; 198 199 /* For read-only block groups */ 200 struct list_head ro_list; 201 202 /* 203 * When non-zero it means the block group's logical address and its 204 * device extents can not be reused for future block group allocations 205 * until the counter goes down to 0. This is to prevent them from being 206 * reused while some task is still using the block group after it was 207 * deleted - we want to make sure they can only be reused for new block 208 * groups after that task is done with the deleted block group. 209 */ 210 atomic_t frozen; 211 212 /* For discard operations */ 213 struct list_head discard_list; 214 int discard_index; 215 u64 discard_eligible_time; 216 u64 discard_cursor; 217 enum btrfs_discard_state discard_state; 218 219 /* For dirty block groups */ 220 struct list_head dirty_list; 221 struct list_head io_list; 222 223 struct btrfs_io_ctl io_ctl; 224 225 /* 226 * Incremented when doing extent allocations and holding a read lock 227 * on the space_info's groups_sem semaphore. 228 * Decremented when an ordered extent that represents an IO against this 229 * block group's range is created (after it's added to its inode's 230 * root's list of ordered extents) or immediately after the allocation 231 * if it's a metadata extent or fallocate extent (for these cases we 232 * don't create ordered extents). 233 */ 234 atomic_t reservations; 235 236 /* 237 * Incremented while holding the spinlock *lock* by a task checking if 238 * it can perform a nocow write (incremented if the value for the *ro* 239 * field is 0). Decremented by such tasks once they create an ordered 240 * extent or before that if some error happens before reaching that step. 241 * This is to prevent races between block group relocation and nocow 242 * writes through direct IO. 243 */ 244 atomic_t nocow_writers; 245 246 /* Lock for free space tree operations. */ 247 struct mutex free_space_lock; 248 249 /* Protected by @free_space_lock. */ 250 bool using_free_space_bitmaps; 251 /* Protected by @free_space_lock. */ 252 bool using_free_space_bitmaps_cached; 253 254 /* 255 * Number of extents in this block group used for swap files. 256 * All accesses protected by the spinlock 'lock'. 257 */ 258 int swap_extents; 259 260 /* 261 * Allocation offset for the block group to implement sequential 262 * allocation. This is used only on a zoned filesystem. 263 */ 264 u64 alloc_offset; 265 u64 zone_unusable; 266 u64 zone_capacity; 267 u64 meta_write_pointer; 268 struct btrfs_chunk_map *physical_map; 269 struct list_head active_bg_list; 270 struct work_struct zone_finish_work; 271 struct extent_buffer *last_eb; 272 enum btrfs_block_group_size_class size_class; 273 u64 reclaim_mark; 274 }; 275 276 static inline u64 btrfs_block_group_end(const struct btrfs_block_group *block_group) 277 { 278 return (block_group->start + block_group->length); 279 } 280 281 static inline bool btrfs_is_block_group_used(const struct btrfs_block_group *bg) 282 { 283 lockdep_assert_held(&bg->lock); 284 285 return (bg->used > 0 || bg->reserved > 0 || bg->pinned > 0); 286 } 287 288 static inline bool btrfs_is_block_group_data_only(const struct btrfs_block_group *block_group) 289 { 290 /* 291 * In mixed mode the fragmentation is expected to be high, lowering the 292 * efficiency, so only proper data block groups are considered. 293 */ 294 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) && 295 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA); 296 } 297 298 #ifdef CONFIG_BTRFS_DEBUG 299 int btrfs_should_fragment_free_space(const struct btrfs_block_group *block_group); 300 #endif 301 302 struct btrfs_block_group *btrfs_lookup_first_block_group( 303 struct btrfs_fs_info *info, u64 bytenr); 304 struct btrfs_block_group *btrfs_lookup_block_group( 305 struct btrfs_fs_info *info, u64 bytenr); 306 struct btrfs_block_group *btrfs_next_block_group( 307 struct btrfs_block_group *cache); 308 void btrfs_get_block_group(struct btrfs_block_group *cache); 309 void btrfs_put_block_group(struct btrfs_block_group *cache); 310 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info, 311 const u64 start); 312 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg); 313 struct btrfs_block_group *btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, 314 u64 bytenr); 315 void btrfs_dec_nocow_writers(struct btrfs_block_group *bg); 316 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg); 317 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache, 318 u64 num_bytes); 319 int btrfs_cache_block_group(struct btrfs_block_group *cache, bool wait); 320 struct btrfs_caching_control *btrfs_get_caching_control( 321 struct btrfs_block_group *cache); 322 int btrfs_add_new_free_space(struct btrfs_block_group *block_group, 323 u64 start, u64 end, u64 *total_added_ret); 324 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( 325 struct btrfs_fs_info *fs_info, 326 const u64 chunk_offset); 327 int btrfs_remove_block_group(struct btrfs_trans_handle *trans, 328 struct btrfs_chunk_map *map); 329 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); 330 void btrfs_mark_bg_unused(struct btrfs_block_group *bg); 331 void btrfs_reclaim_bgs_work(struct work_struct *work); 332 void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info); 333 void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg); 334 int btrfs_read_block_groups(struct btrfs_fs_info *info); 335 struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans, 336 struct btrfs_space_info *space_info, 337 u64 type, u64 chunk_offset, u64 size); 338 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans); 339 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache, 340 bool do_chunk_alloc); 341 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache); 342 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans); 343 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans); 344 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans); 345 int btrfs_update_block_group(struct btrfs_trans_handle *trans, 346 u64 bytenr, u64 num_bytes, bool alloc); 347 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache, 348 u64 ram_bytes, u64 num_bytes, int delalloc, 349 bool force_wrong_size_class); 350 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, u64 num_bytes, 351 bool is_delalloc); 352 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, 353 struct btrfs_space_info *space_info, u64 flags, 354 enum btrfs_chunk_alloc_enum force); 355 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type); 356 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type); 357 void btrfs_reserve_chunk_metadata(struct btrfs_trans_handle *trans, 358 bool is_item_insertion); 359 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags); 360 void btrfs_put_block_group_cache(struct btrfs_fs_info *info); 361 int btrfs_free_block_groups(struct btrfs_fs_info *info); 362 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 363 u64 physical, u64 **logical, int *naddrs, int *stripe_len); 364 365 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info) 366 { 367 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA); 368 } 369 370 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info) 371 { 372 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA); 373 } 374 375 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info) 376 { 377 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM); 378 } 379 380 static inline int btrfs_block_group_done(const struct btrfs_block_group *cache) 381 { 382 smp_mb(); 383 return cache->cached == BTRFS_CACHE_FINISHED || 384 cache->cached == BTRFS_CACHE_ERROR; 385 } 386 387 void btrfs_freeze_block_group(struct btrfs_block_group *cache); 388 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache); 389 390 bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg); 391 void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount); 392 393 enum btrfs_block_group_size_class btrfs_calc_block_group_size_class(u64 size); 394 int btrfs_use_block_group_size_class(struct btrfs_block_group *bg, 395 enum btrfs_block_group_size_class size_class, 396 bool force_wrong_size_class); 397 bool btrfs_block_group_should_use_size_class(const struct btrfs_block_group *bg); 398 399 #endif /* BTRFS_BLOCK_GROUP_H */ 400