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 /* Usage count */ 118 atomic_t count; 119 120 /* 121 * List of struct btrfs_free_clusters for this block group. 122 * Today it will only have one thing on it, but that may change 123 */ 124 struct list_head cluster_list; 125 126 /* For delayed block group creation or deletion of empty block groups */ 127 struct list_head bg_list; 128 129 /* For read-only block groups */ 130 struct list_head ro_list; 131 132 /* 133 * When non-zero it means the block group's logical address and its 134 * device extents can not be reused for future block group allocations 135 * until the counter goes down to 0. This is to prevent them from being 136 * reused while some task is still using the block group after it was 137 * deleted - we want to make sure they can only be reused for new block 138 * groups after that task is done with the deleted block group. 139 */ 140 atomic_t frozen; 141 142 /* For discard operations */ 143 struct list_head discard_list; 144 int discard_index; 145 u64 discard_eligible_time; 146 u64 discard_cursor; 147 enum btrfs_discard_state discard_state; 148 149 /* For dirty block groups */ 150 struct list_head dirty_list; 151 struct list_head io_list; 152 153 struct btrfs_io_ctl io_ctl; 154 155 /* 156 * Incremented when doing extent allocations and holding a read lock 157 * on the space_info's groups_sem semaphore. 158 * Decremented when an ordered extent that represents an IO against this 159 * block group's range is created (after it's added to its inode's 160 * root's list of ordered extents) or immediately after the allocation 161 * if it's a metadata extent or fallocate extent (for these cases we 162 * don't create ordered extents). 163 */ 164 atomic_t reservations; 165 166 /* 167 * Incremented while holding the spinlock *lock* by a task checking if 168 * it can perform a nocow write (incremented if the value for the *ro* 169 * field is 0). Decremented by such tasks once they create an ordered 170 * extent or before that if some error happens before reaching that step. 171 * This is to prevent races between block group relocation and nocow 172 * writes through direct IO. 173 */ 174 atomic_t nocow_writers; 175 176 /* Lock for free space tree operations. */ 177 struct mutex free_space_lock; 178 179 /* 180 * Does the block group need to be added to the free space tree? 181 * Protected by free_space_lock. 182 */ 183 int needs_free_space; 184 185 /* Record locked full stripes for RAID5/6 block group */ 186 struct btrfs_full_stripe_locks_tree full_stripe_locks_root; 187 }; 188 189 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group) 190 { 191 return (block_group->start + block_group->length); 192 } 193 194 static inline bool btrfs_is_block_group_data_only( 195 struct btrfs_block_group *block_group) 196 { 197 /* 198 * In mixed mode the fragmentation is expected to be high, lowering the 199 * efficiency, so only proper data block groups are considered. 200 */ 201 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) && 202 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA); 203 } 204 205 #ifdef CONFIG_BTRFS_DEBUG 206 static inline int btrfs_should_fragment_free_space( 207 struct btrfs_block_group *block_group) 208 { 209 struct btrfs_fs_info *fs_info = block_group->fs_info; 210 211 return (btrfs_test_opt(fs_info, FRAGMENT_METADATA) && 212 block_group->flags & BTRFS_BLOCK_GROUP_METADATA) || 213 (btrfs_test_opt(fs_info, FRAGMENT_DATA) && 214 block_group->flags & BTRFS_BLOCK_GROUP_DATA); 215 } 216 #endif 217 218 struct btrfs_block_group *btrfs_lookup_first_block_group( 219 struct btrfs_fs_info *info, u64 bytenr); 220 struct btrfs_block_group *btrfs_lookup_block_group( 221 struct btrfs_fs_info *info, u64 bytenr); 222 struct btrfs_block_group *btrfs_next_block_group( 223 struct btrfs_block_group *cache); 224 void btrfs_get_block_group(struct btrfs_block_group *cache); 225 void btrfs_put_block_group(struct btrfs_block_group *cache); 226 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info, 227 const u64 start); 228 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg); 229 bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr); 230 void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr); 231 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg); 232 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache, 233 u64 num_bytes); 234 int btrfs_wait_block_group_cache_done(struct btrfs_block_group *cache); 235 int btrfs_cache_block_group(struct btrfs_block_group *cache, 236 int load_cache_only); 237 void btrfs_put_caching_control(struct btrfs_caching_control *ctl); 238 struct btrfs_caching_control *btrfs_get_caching_control( 239 struct btrfs_block_group *cache); 240 u64 add_new_free_space(struct btrfs_block_group *block_group, 241 u64 start, u64 end); 242 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group( 243 struct btrfs_fs_info *fs_info, 244 const u64 chunk_offset); 245 int btrfs_remove_block_group(struct btrfs_trans_handle *trans, 246 u64 group_start, struct extent_map *em); 247 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info); 248 void btrfs_mark_bg_unused(struct btrfs_block_group *bg); 249 int btrfs_read_block_groups(struct btrfs_fs_info *info); 250 int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 bytes_used, 251 u64 type, u64 chunk_offset, u64 size); 252 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans); 253 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache, 254 bool do_chunk_alloc); 255 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache); 256 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans); 257 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans); 258 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans); 259 int btrfs_update_block_group(struct btrfs_trans_handle *trans, 260 u64 bytenr, u64 num_bytes, int alloc); 261 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache, 262 u64 ram_bytes, u64 num_bytes, int delalloc); 263 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, 264 u64 num_bytes, int delalloc); 265 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans, u64 flags, 266 enum btrfs_chunk_alloc_enum force); 267 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type); 268 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type); 269 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags); 270 void btrfs_put_block_group_cache(struct btrfs_fs_info *info); 271 int btrfs_free_block_groups(struct btrfs_fs_info *info); 272 273 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info) 274 { 275 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA); 276 } 277 278 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info) 279 { 280 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA); 281 } 282 283 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info) 284 { 285 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM); 286 } 287 288 static inline int btrfs_block_group_done(struct btrfs_block_group *cache) 289 { 290 smp_mb(); 291 return cache->cached == BTRFS_CACHE_FINISHED || 292 cache->cached == BTRFS_CACHE_ERROR; 293 } 294 295 void btrfs_freeze_block_group(struct btrfs_block_group *cache); 296 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache); 297 298 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 299 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 300 u64 physical, u64 **logical, int *naddrs, int *stripe_len); 301 #endif 302 303 #endif /* BTRFS_BLOCK_GROUP_H */ 304