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 /* Indicate that the block group is placed on a sequential zone */ 87 BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE, 88 /* 89 * Indicate that block group is in the list of new block groups of a 90 * transaction. 91 */ 92 BLOCK_GROUP_FLAG_NEW, 93 }; 94 95 enum btrfs_caching_type { 96 BTRFS_CACHE_NO, 97 BTRFS_CACHE_STARTED, 98 BTRFS_CACHE_FINISHED, 99 BTRFS_CACHE_ERROR, 100 }; 101 102 struct btrfs_caching_control { 103 struct list_head list; 104 struct mutex mutex; 105 wait_queue_head_t wait; 106 struct btrfs_work work; 107 struct btrfs_block_group *block_group; 108 /* Track progress of caching during allocation. */ 109 atomic_t progress; 110 refcount_t count; 111 }; 112 113 /* Once caching_thread() finds this much free space, it will wake up waiters. */ 114 #define CACHING_CTL_WAKE_UP SZ_2M 115 116 struct btrfs_block_group { 117 struct btrfs_fs_info *fs_info; 118 struct btrfs_inode *inode; 119 spinlock_t lock; 120 u64 start; 121 u64 length; 122 u64 pinned; 123 u64 reserved; 124 u64 used; 125 u64 delalloc_bytes; 126 u64 bytes_super; 127 u64 flags; 128 u64 cache_generation; 129 u64 global_root_id; 130 131 /* 132 * The last committed used bytes of this block group, if the above @used 133 * is still the same as @commit_used, we don't need to update block 134 * group item of this block group. 135 */ 136 u64 commit_used; 137 /* 138 * If the free space extent count exceeds this number, convert the block 139 * group to bitmaps. 140 */ 141 u32 bitmap_high_thresh; 142 143 /* 144 * If the free space extent count drops below this number, convert the 145 * block group back to extents. 146 */ 147 u32 bitmap_low_thresh; 148 149 /* 150 * It is just used for the delayed data space allocation because 151 * only the data space allocation and the relative metadata update 152 * can be done cross the transaction. 153 */ 154 struct rw_semaphore data_rwsem; 155 156 /* For raid56, this is a full stripe, without parity */ 157 unsigned long full_stripe_len; 158 unsigned long runtime_flags; 159 160 unsigned int ro; 161 162 int disk_cache_state; 163 164 /* Cache tracking stuff */ 165 int cached; 166 struct btrfs_caching_control *caching_ctl; 167 168 struct btrfs_space_info *space_info; 169 170 /* Free space cache stuff */ 171 struct btrfs_free_space_ctl *free_space_ctl; 172 173 /* Block group cache stuff */ 174 struct rb_node cache_node; 175 176 /* For block groups in the same raid type */ 177 struct list_head list; 178 179 refcount_t refs; 180 181 /* 182 * List of struct btrfs_free_clusters for this block group. 183 * Today it will only have one thing on it, but that may change 184 */ 185 struct list_head cluster_list; 186 187 /* 188 * Used for several lists: 189 * 190 * 1) struct btrfs_fs_info::unused_bgs 191 * 2) struct btrfs_fs_info::reclaim_bgs 192 * 3) struct btrfs_transaction::deleted_bgs 193 * 4) struct btrfs_trans_handle::new_bgs 194 */ 195 struct list_head bg_list; 196 197 /* For read-only block groups */ 198 struct list_head ro_list; 199 200 /* 201 * When non-zero it means the block group's logical address and its 202 * device extents can not be reused for future block group allocations 203 * until the counter goes down to 0. This is to prevent them from being 204 * reused while some task is still using the block group after it was 205 * deleted - we want to make sure they can only be reused for new block 206 * groups after that task is done with the deleted block group. 207 */ 208 atomic_t frozen; 209 210 /* For discard operations */ 211 struct list_head discard_list; 212 int discard_index; 213 u64 discard_eligible_time; 214 u64 discard_cursor; 215 enum btrfs_discard_state discard_state; 216 217 /* For dirty block groups */ 218 struct list_head dirty_list; 219 struct list_head io_list; 220 221 struct btrfs_io_ctl io_ctl; 222 223 /* 224 * Incremented when doing extent allocations and holding a read lock 225 * on the space_info's groups_sem semaphore. 226 * Decremented when an ordered extent that represents an IO against this 227 * block group's range is created (after it's added to its inode's 228 * root's list of ordered extents) or immediately after the allocation 229 * if it's a metadata extent or fallocate extent (for these cases we 230 * don't create ordered extents). 231 */ 232 atomic_t reservations; 233 234 /* 235 * Incremented while holding the spinlock *lock* by a task checking if 236 * it can perform a nocow write (incremented if the value for the *ro* 237 * field is 0). Decremented by such tasks once they create an ordered 238 * extent or before that if some error happens before reaching that step. 239 * This is to prevent races between block group relocation and nocow 240 * writes through direct IO. 241 */ 242 atomic_t nocow_writers; 243 244 /* Lock for free space tree operations. */ 245 struct mutex free_space_lock; 246 247 /* 248 * Number of extents in this block group used for swap files. 249 * All accesses protected by the spinlock 'lock'. 250 */ 251 int swap_extents; 252 253 /* 254 * Allocation offset for the block group to implement sequential 255 * allocation. This is used only on a zoned filesystem. 256 */ 257 u64 alloc_offset; 258 u64 zone_unusable; 259 u64 zone_capacity; 260 u64 meta_write_pointer; 261 struct btrfs_chunk_map *physical_map; 262 struct list_head active_bg_list; 263 struct work_struct zone_finish_work; 264 struct extent_buffer *last_eb; 265 enum btrfs_block_group_size_class size_class; 266 u64 reclaim_mark; 267 }; 268 269 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group) 270 { 271 return (block_group->start + block_group->length); 272 } 273 274 static inline bool btrfs_is_block_group_used(const struct btrfs_block_group *bg) 275 { 276 lockdep_assert_held(&bg->lock); 277 278 return (bg->used > 0 || bg->reserved > 0 || bg->pinned > 0); 279 } 280 281 static inline bool btrfs_is_block_group_data_only( 282 struct btrfs_block_group *block_group) 283 { 284 /* 285 * In mixed mode the fragmentation is expected to be high, lowering the 286 * efficiency, so only proper data block groups are considered. 287 */ 288 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) && 289 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA); 290 } 291 292 #ifdef CONFIG_BTRFS_DEBUG 293 int btrfs_should_fragment_free_space(struct btrfs_block_group *block_group); 294 #endif 295 296 struct btrfs_block_group *btrfs_lookup_first_block_group( 297 struct btrfs_fs_info *info, u64 bytenr); 298 struct btrfs_block_group *btrfs_lookup_block_group( 299 struct btrfs_fs_info *info, u64 bytenr); 300 struct btrfs_block_group *btrfs_next_block_group( 301 struct btrfs_block_group *cache); 302 void btrfs_get_block_group(struct btrfs_block_group *cache); 303 void btrfs_put_block_group(struct btrfs_block_group *cache); 304 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info, 305 const u64 start); 306 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg); 307 struct btrfs_block_group *btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, 308 u64 bytenr); 309 void btrfs_dec_nocow_writers(struct btrfs_block_group *bg); 310 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg); 311 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache, 312 u64 num_bytes); 313 int btrfs_cache_block_group(struct btrfs_block_group *cache, bool wait); 314 struct btrfs_caching_control *btrfs_get_caching_control( 315 struct btrfs_block_group *cache); 316 int btrfs_add_new_free_space(struct btrfs_block_group *block_group, 317 u64 start, u64 end, u64 *total_added_ret); 318 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( 319 struct btrfs_fs_info *fs_info, 320 const u64 chunk_offset); 321 int btrfs_remove_block_group(struct btrfs_trans_handle *trans, 322 struct btrfs_chunk_map *map); 323 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); 324 void btrfs_mark_bg_unused(struct btrfs_block_group *bg); 325 void btrfs_reclaim_bgs_work(struct work_struct *work); 326 void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info); 327 void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg); 328 int btrfs_read_block_groups(struct btrfs_fs_info *info); 329 struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans, 330 u64 type, 331 u64 chunk_offset, u64 size); 332 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans); 333 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache, 334 bool do_chunk_alloc); 335 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache); 336 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans); 337 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans); 338 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans); 339 int btrfs_update_block_group(struct btrfs_trans_handle *trans, 340 u64 bytenr, u64 num_bytes, bool alloc); 341 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache, 342 u64 ram_bytes, u64 num_bytes, int delalloc, 343 bool force_wrong_size_class); 344 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, 345 u64 num_bytes, int delalloc); 346 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags, 347 enum btrfs_chunk_alloc_enum force); 348 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type); 349 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type); 350 void btrfs_reserve_chunk_metadata(struct btrfs_trans_handle *trans, 351 bool is_item_insertion); 352 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags); 353 void btrfs_put_block_group_cache(struct btrfs_fs_info *info); 354 int btrfs_free_block_groups(struct btrfs_fs_info *info); 355 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 356 u64 physical, u64 **logical, int *naddrs, int *stripe_len); 357 358 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info) 359 { 360 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA); 361 } 362 363 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info) 364 { 365 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA); 366 } 367 368 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info) 369 { 370 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM); 371 } 372 373 static inline int btrfs_block_group_done(struct btrfs_block_group *cache) 374 { 375 smp_mb(); 376 return cache->cached == BTRFS_CACHE_FINISHED || 377 cache->cached == BTRFS_CACHE_ERROR; 378 } 379 380 void btrfs_freeze_block_group(struct btrfs_block_group *cache); 381 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache); 382 383 bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg); 384 void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount); 385 386 enum btrfs_block_group_size_class btrfs_calc_block_group_size_class(u64 size); 387 int btrfs_use_block_group_size_class(struct btrfs_block_group *bg, 388 enum btrfs_block_group_size_class size_class, 389 bool force_wrong_size_class); 390 bool btrfs_block_group_should_use_size_class(struct btrfs_block_group *bg); 391 392 #endif /* BTRFS_BLOCK_GROUP_H */ 393