1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef BTRFS_BLOCK_GROUP_H 4 #define BTRFS_BLOCK_GROUP_H 5 6 #include "free-space-cache.h" 7 8 enum btrfs_disk_cache_state { 9 BTRFS_DC_WRITTEN, 10 BTRFS_DC_ERROR, 11 BTRFS_DC_CLEAR, 12 BTRFS_DC_SETUP, 13 }; 14 15 /* 16 * This describes the state of the block_group for async discard. This is due 17 * to the two pass nature of it where extent discarding is prioritized over 18 * bitmap discarding. BTRFS_DISCARD_RESET_CURSOR is set when we are resetting 19 * between lists to prevent contention for discard state variables 20 * (eg. discard_cursor). 21 */ 22 enum btrfs_discard_state { 23 BTRFS_DISCARD_EXTENTS, 24 BTRFS_DISCARD_BITMAPS, 25 BTRFS_DISCARD_RESET_CURSOR, 26 }; 27 28 /* 29 * Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to 30 * only allocate a chunk if we really need one. 31 * 32 * CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few 33 * chunks already allocated. This is used as part of the clustering code to 34 * help make sure we have a good pool of storage to cluster in, without filling 35 * the FS with empty chunks 36 * 37 * CHUNK_ALLOC_FORCE means it must try to allocate one 38 */ 39 enum btrfs_chunk_alloc_enum { 40 CHUNK_ALLOC_NO_FORCE, 41 CHUNK_ALLOC_LIMITED, 42 CHUNK_ALLOC_FORCE, 43 }; 44 45 struct btrfs_caching_control { 46 struct list_head list; 47 struct mutex mutex; 48 wait_queue_head_t wait; 49 struct btrfs_work work; 50 struct btrfs_block_group *block_group; 51 u64 progress; 52 refcount_t count; 53 }; 54 55 /* Once caching_thread() finds this much free space, it will wake up waiters. */ 56 #define CACHING_CTL_WAKE_UP SZ_2M 57 58 struct btrfs_block_group { 59 struct btrfs_fs_info *fs_info; 60 struct inode *inode; 61 spinlock_t lock; 62 u64 start; 63 u64 length; 64 u64 pinned; 65 u64 reserved; 66 u64 used; 67 u64 delalloc_bytes; 68 u64 bytes_super; 69 u64 flags; 70 u64 cache_generation; 71 72 /* 73 * If the free space extent count exceeds this number, convert the block 74 * group to bitmaps. 75 */ 76 u32 bitmap_high_thresh; 77 78 /* 79 * If the free space extent count drops below this number, convert the 80 * block group back to extents. 81 */ 82 u32 bitmap_low_thresh; 83 84 /* 85 * It is just used for the delayed data space allocation because 86 * only the data space allocation and the relative metadata update 87 * can be done cross the transaction. 88 */ 89 struct rw_semaphore data_rwsem; 90 91 /* For raid56, this is a full stripe, without parity */ 92 unsigned long full_stripe_len; 93 94 unsigned int ro; 95 unsigned int iref:1; 96 unsigned int has_caching_ctl:1; 97 unsigned int removed:1; 98 unsigned int to_copy:1; 99 unsigned int relocating_repair:1; 100 101 int disk_cache_state; 102 103 /* Cache tracking stuff */ 104 int cached; 105 struct btrfs_caching_control *caching_ctl; 106 u64 last_byte_to_unpin; 107 108 struct btrfs_space_info *space_info; 109 110 /* Free space cache stuff */ 111 struct btrfs_free_space_ctl *free_space_ctl; 112 113 /* Block group cache stuff */ 114 struct rb_node cache_node; 115 116 /* For block groups in the same raid type */ 117 struct list_head list; 118 119 refcount_t refs; 120 121 /* 122 * List of struct btrfs_free_clusters for this block group. 123 * Today it will only have one thing on it, but that may change 124 */ 125 struct list_head cluster_list; 126 127 /* For delayed block group creation or deletion of empty block groups */ 128 struct list_head bg_list; 129 130 /* For read-only block groups */ 131 struct list_head ro_list; 132 133 /* 134 * When non-zero it means the block group's logical address and its 135 * device extents can not be reused for future block group allocations 136 * until the counter goes down to 0. This is to prevent them from being 137 * reused while some task is still using the block group after it was 138 * deleted - we want to make sure they can only be reused for new block 139 * groups after that task is done with the deleted block group. 140 */ 141 atomic_t frozen; 142 143 /* For discard operations */ 144 struct list_head discard_list; 145 int discard_index; 146 u64 discard_eligible_time; 147 u64 discard_cursor; 148 enum btrfs_discard_state discard_state; 149 150 /* For dirty block groups */ 151 struct list_head dirty_list; 152 struct list_head io_list; 153 154 struct btrfs_io_ctl io_ctl; 155 156 /* 157 * Incremented when doing extent allocations and holding a read lock 158 * on the space_info's groups_sem semaphore. 159 * Decremented when an ordered extent that represents an IO against this 160 * block group's range is created (after it's added to its inode's 161 * root's list of ordered extents) or immediately after the allocation 162 * if it's a metadata extent or fallocate extent (for these cases we 163 * don't create ordered extents). 164 */ 165 atomic_t reservations; 166 167 /* 168 * Incremented while holding the spinlock *lock* by a task checking if 169 * it can perform a nocow write (incremented if the value for the *ro* 170 * field is 0). Decremented by such tasks once they create an ordered 171 * extent or before that if some error happens before reaching that step. 172 * This is to prevent races between block group relocation and nocow 173 * writes through direct IO. 174 */ 175 atomic_t nocow_writers; 176 177 /* Lock for free space tree operations. */ 178 struct mutex free_space_lock; 179 180 /* 181 * Does the block group need to be added to the free space tree? 182 * Protected by free_space_lock. 183 */ 184 int needs_free_space; 185 186 /* Flag indicating this block group is placed on a sequential zone */ 187 bool seq_zone; 188 189 /* 190 * Number of extents in this block group used for swap files. 191 * All accesses protected by the spinlock 'lock'. 192 */ 193 int swap_extents; 194 195 /* Record locked full stripes for RAID5/6 block group */ 196 struct btrfs_full_stripe_locks_tree full_stripe_locks_root; 197 198 /* 199 * Allocation offset for the block group to implement sequential 200 * allocation. This is used only on a zoned filesystem. 201 */ 202 u64 alloc_offset; 203 u64 zone_unusable; 204 u64 meta_write_pointer; 205 }; 206 207 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group) 208 { 209 return (block_group->start + block_group->length); 210 } 211 212 static inline bool btrfs_is_block_group_data_only( 213 struct btrfs_block_group *block_group) 214 { 215 /* 216 * In mixed mode the fragmentation is expected to be high, lowering the 217 * efficiency, so only proper data block groups are considered. 218 */ 219 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) && 220 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA); 221 } 222 223 #ifdef CONFIG_BTRFS_DEBUG 224 static inline int btrfs_should_fragment_free_space( 225 struct btrfs_block_group *block_group) 226 { 227 struct btrfs_fs_info *fs_info = block_group->fs_info; 228 229 return (btrfs_test_opt(fs_info, FRAGMENT_METADATA) && 230 block_group->flags & BTRFS_BLOCK_GROUP_METADATA) || 231 (btrfs_test_opt(fs_info, FRAGMENT_DATA) && 232 block_group->flags & BTRFS_BLOCK_GROUP_DATA); 233 } 234 #endif 235 236 struct btrfs_block_group *btrfs_lookup_first_block_group( 237 struct btrfs_fs_info *info, u64 bytenr); 238 struct btrfs_block_group *btrfs_lookup_block_group( 239 struct btrfs_fs_info *info, u64 bytenr); 240 struct btrfs_block_group *btrfs_next_block_group( 241 struct btrfs_block_group *cache); 242 void btrfs_get_block_group(struct btrfs_block_group *cache); 243 void btrfs_put_block_group(struct btrfs_block_group *cache); 244 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info, 245 const u64 start); 246 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg); 247 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr); 248 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr); 249 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg); 250 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache, 251 u64 num_bytes); 252 int btrfs_wait_block_group_cache_done(struct btrfs_block_group *cache); 253 int btrfs_cache_block_group(struct btrfs_block_group *cache, 254 int load_cache_only); 255 void btrfs_put_caching_control(struct btrfs_caching_control *ctl); 256 struct btrfs_caching_control *btrfs_get_caching_control( 257 struct btrfs_block_group *cache); 258 u64 add_new_free_space(struct btrfs_block_group *block_group, 259 u64 start, u64 end); 260 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( 261 struct btrfs_fs_info *fs_info, 262 const u64 chunk_offset); 263 int btrfs_remove_block_group(struct btrfs_trans_handle *trans, 264 u64 group_start, struct extent_map *em); 265 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); 266 void btrfs_mark_bg_unused(struct btrfs_block_group *bg); 267 int btrfs_read_block_groups(struct btrfs_fs_info *info); 268 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used, 269 u64 type, u64 chunk_offset, u64 size); 270 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans); 271 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache, 272 bool do_chunk_alloc); 273 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache); 274 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans); 275 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans); 276 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans); 277 int btrfs_update_block_group(struct btrfs_trans_handle *trans, 278 u64 bytenr, u64 num_bytes, int alloc); 279 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache, 280 u64 ram_bytes, u64 num_bytes, int delalloc); 281 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, 282 u64 num_bytes, int delalloc); 283 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags, 284 enum btrfs_chunk_alloc_enum force); 285 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type); 286 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type); 287 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags); 288 void btrfs_put_block_group_cache(struct btrfs_fs_info *info); 289 int btrfs_free_block_groups(struct btrfs_fs_info *info); 290 void btrfs_wait_space_cache_v1_finished(struct btrfs_block_group *cache, 291 struct btrfs_caching_control *caching_ctl); 292 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 293 struct block_device *bdev, u64 physical, u64 **logical, 294 int *naddrs, int *stripe_len); 295 296 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info) 297 { 298 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA); 299 } 300 301 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info) 302 { 303 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA); 304 } 305 306 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info) 307 { 308 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM); 309 } 310 311 static inline int btrfs_block_group_done(struct btrfs_block_group *cache) 312 { 313 smp_mb(); 314 return cache->cached == BTRFS_CACHE_FINISHED || 315 cache->cached == BTRFS_CACHE_ERROR; 316 } 317 318 void btrfs_freeze_block_group(struct btrfs_block_group *cache); 319 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache); 320 321 bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg); 322 void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount); 323 324 #endif /* BTRFS_BLOCK_GROUP_H */ 325