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 99 int disk_cache_state; 100 101 /* Cache tracking stuff */ 102 int cached; 103 struct btrfs_caching_control *caching_ctl; 104 u64 last_byte_to_unpin; 105 106 struct btrfs_space_info *space_info; 107 108 /* Free space cache stuff */ 109 struct btrfs_free_space_ctl *free_space_ctl; 110 111 /* Block group cache stuff */ 112 struct rb_node cache_node; 113 114 /* For block groups in the same raid type */ 115 struct list_head list; 116 117 refcount_t refs; 118 119 /* 120 * List of struct btrfs_free_clusters for this block group. 121 * Today it will only have one thing on it, but that may change 122 */ 123 struct list_head cluster_list; 124 125 /* For delayed block group creation or deletion of empty block groups */ 126 struct list_head bg_list; 127 128 /* For read-only block groups */ 129 struct list_head ro_list; 130 131 /* 132 * When non-zero it means the block group's logical address and its 133 * device extents can not be reused for future block group allocations 134 * until the counter goes down to 0. This is to prevent them from being 135 * reused while some task is still using the block group after it was 136 * deleted - we want to make sure they can only be reused for new block 137 * groups after that task is done with the deleted block group. 138 */ 139 atomic_t frozen; 140 141 /* For discard operations */ 142 struct list_head discard_list; 143 int discard_index; 144 u64 discard_eligible_time; 145 u64 discard_cursor; 146 enum btrfs_discard_state discard_state; 147 148 /* For dirty block groups */ 149 struct list_head dirty_list; 150 struct list_head io_list; 151 152 struct btrfs_io_ctl io_ctl; 153 154 /* 155 * Incremented when doing extent allocations and holding a read lock 156 * on the space_info's groups_sem semaphore. 157 * Decremented when an ordered extent that represents an IO against this 158 * block group's range is created (after it's added to its inode's 159 * root's list of ordered extents) or immediately after the allocation 160 * if it's a metadata extent or fallocate extent (for these cases we 161 * don't create ordered extents). 162 */ 163 atomic_t reservations; 164 165 /* 166 * Incremented while holding the spinlock *lock* by a task checking if 167 * it can perform a nocow write (incremented if the value for the *ro* 168 * field is 0). Decremented by such tasks once they create an ordered 169 * extent or before that if some error happens before reaching that step. 170 * This is to prevent races between block group relocation and nocow 171 * writes through direct IO. 172 */ 173 atomic_t nocow_writers; 174 175 /* Lock for free space tree operations. */ 176 struct mutex free_space_lock; 177 178 /* 179 * Does the block group need to be added to the free space tree? 180 * Protected by free_space_lock. 181 */ 182 int needs_free_space; 183 184 /* Record locked full stripes for RAID5/6 block group */ 185 struct btrfs_full_stripe_locks_tree full_stripe_locks_root; 186 }; 187 188 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group) 189 { 190 return (block_group->start + block_group->length); 191 } 192 193 static inline bool btrfs_is_block_group_data_only( 194 struct btrfs_block_group *block_group) 195 { 196 /* 197 * In mixed mode the fragmentation is expected to be high, lowering the 198 * efficiency, so only proper data block groups are considered. 199 */ 200 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) && 201 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA); 202 } 203 204 #ifdef CONFIG_BTRFS_DEBUG 205 static inline int btrfs_should_fragment_free_space( 206 struct btrfs_block_group *block_group) 207 { 208 struct btrfs_fs_info *fs_info = block_group->fs_info; 209 210 return (btrfs_test_opt(fs_info, FRAGMENT_METADATA) && 211 block_group->flags & BTRFS_BLOCK_GROUP_METADATA) || 212 (btrfs_test_opt(fs_info, FRAGMENT_DATA) && 213 block_group->flags & BTRFS_BLOCK_GROUP_DATA); 214 } 215 #endif 216 217 struct btrfs_block_group *btrfs_lookup_first_block_group( 218 struct btrfs_fs_info *info, u64 bytenr); 219 struct btrfs_block_group *btrfs_lookup_block_group( 220 struct btrfs_fs_info *info, u64 bytenr); 221 struct btrfs_block_group *btrfs_next_block_group( 222 struct btrfs_block_group *cache); 223 void btrfs_get_block_group(struct btrfs_block_group *cache); 224 void btrfs_put_block_group(struct btrfs_block_group *cache); 225 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info, 226 const u64 start); 227 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg); 228 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr); 229 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr); 230 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg); 231 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache, 232 u64 num_bytes); 233 int btrfs_wait_block_group_cache_done(struct btrfs_block_group *cache); 234 int btrfs_cache_block_group(struct btrfs_block_group *cache, 235 int load_cache_only); 236 void btrfs_put_caching_control(struct btrfs_caching_control *ctl); 237 struct btrfs_caching_control *btrfs_get_caching_control( 238 struct btrfs_block_group *cache); 239 u64 add_new_free_space(struct btrfs_block_group *block_group, 240 u64 start, u64 end); 241 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( 242 struct btrfs_fs_info *fs_info, 243 const u64 chunk_offset); 244 int btrfs_remove_block_group(struct btrfs_trans_handle *trans, 245 u64 group_start, struct extent_map *em); 246 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); 247 void btrfs_mark_bg_unused(struct btrfs_block_group *bg); 248 int btrfs_read_block_groups(struct btrfs_fs_info *info); 249 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used, 250 u64 type, u64 chunk_offset, u64 size); 251 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans); 252 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache, 253 bool do_chunk_alloc); 254 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache); 255 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans); 256 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans); 257 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans); 258 int btrfs_update_block_group(struct btrfs_trans_handle *trans, 259 u64 bytenr, u64 num_bytes, int alloc); 260 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache, 261 u64 ram_bytes, u64 num_bytes, int delalloc); 262 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, 263 u64 num_bytes, int delalloc); 264 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags, 265 enum btrfs_chunk_alloc_enum force); 266 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type); 267 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type); 268 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags); 269 void btrfs_put_block_group_cache(struct btrfs_fs_info *info); 270 int btrfs_free_block_groups(struct btrfs_fs_info *info); 271 272 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info) 273 { 274 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA); 275 } 276 277 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info) 278 { 279 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA); 280 } 281 282 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info) 283 { 284 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM); 285 } 286 287 static inline int btrfs_block_group_done(struct btrfs_block_group *cache) 288 { 289 smp_mb(); 290 return cache->cached == BTRFS_CACHE_FINISHED || 291 cache->cached == BTRFS_CACHE_ERROR; 292 } 293 294 void btrfs_freeze_block_group(struct btrfs_block_group *cache); 295 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache); 296 297 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 298 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 299 u64 physical, u64 **logical, int *naddrs, int *stripe_len); 300 #endif 301 302 #endif /* BTRFS_BLOCK_GROUP_H */ 303