1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2014 Facebook. All rights reserved. 4 */ 5 6 #ifndef BTRFS_QGROUP_H 7 #define BTRFS_QGROUP_H 8 9 #include <linux/types.h> 10 #include <linux/spinlock.h> 11 #include <linux/rbtree.h> 12 #include <linux/kobject.h> 13 #include <linux/list.h> 14 #include <uapi/linux/btrfs_tree.h> 15 16 struct extent_buffer; 17 struct extent_changeset; 18 struct btrfs_delayed_extent_op; 19 struct btrfs_fs_info; 20 struct btrfs_root; 21 struct btrfs_ioctl_quota_ctl_args; 22 struct btrfs_trans_handle; 23 struct btrfs_delayed_ref_root; 24 struct btrfs_inode; 25 26 /* 27 * Btrfs qgroup overview 28 * 29 * Btrfs qgroup splits into 3 main part: 30 * 1) Reserve 31 * Reserve metadata/data space for incoming operations 32 * Affect how qgroup limit works 33 * 34 * 2) Trace 35 * Tell btrfs qgroup to trace dirty extents. 36 * 37 * Dirty extents including: 38 * - Newly allocated extents 39 * - Extents going to be deleted (in this trans) 40 * - Extents whose owner is going to be modified 41 * 42 * This is the main part affects whether qgroup numbers will stay 43 * consistent. 44 * Btrfs qgroup can trace clean extents and won't cause any problem, 45 * but it will consume extra CPU time, it should be avoided if possible. 46 * 47 * 3) Account 48 * Btrfs qgroup will updates its numbers, based on dirty extents traced 49 * in previous step. 50 * 51 * Normally at qgroup rescan and transaction commit time. 52 */ 53 54 /* 55 * Special performance optimization for balance. 56 * 57 * For balance, we need to swap subtree of subvolume and reloc trees. 58 * In theory, we need to trace all subtree blocks of both subvolume and reloc 59 * trees, since their owner has changed during such swap. 60 * 61 * However since balance has ensured that both subtrees are containing the 62 * same contents and have the same tree structures, such swap won't cause 63 * qgroup number change. 64 * 65 * But there is a race window between subtree swap and transaction commit, 66 * during that window, if we increase/decrease tree level or merge/split tree 67 * blocks, we still need to trace the original subtrees. 68 * 69 * So for balance, we use a delayed subtree tracing, whose workflow is: 70 * 71 * 1) Record the subtree root block get swapped. 72 * 73 * During subtree swap: 74 * O = Old tree blocks 75 * N = New tree blocks 76 * reloc tree subvolume tree X 77 * Root Root 78 * / \ / \ 79 * NA OB OA OB 80 * / | | \ / | | \ 81 * NC ND OE OF OC OD OE OF 82 * 83 * In this case, NA and OA are going to be swapped, record (NA, OA) into 84 * subvolume tree X. 85 * 86 * 2) After subtree swap. 87 * reloc tree subvolume tree X 88 * Root Root 89 * / \ / \ 90 * OA OB NA OB 91 * / | | \ / | | \ 92 * OC OD OE OF NC ND OE OF 93 * 94 * 3a) COW happens for OB 95 * If we are going to COW tree block OB, we check OB's bytenr against 96 * tree X's swapped_blocks structure. 97 * If it doesn't fit any, nothing will happen. 98 * 99 * 3b) COW happens for NA 100 * Check NA's bytenr against tree X's swapped_blocks, and get a hit. 101 * Then we do subtree scan on both subtrees OA and NA. 102 * Resulting 6 tree blocks to be scanned (OA, OC, OD, NA, NC, ND). 103 * 104 * Then no matter what we do to subvolume tree X, qgroup numbers will 105 * still be correct. 106 * Then NA's record gets removed from X's swapped_blocks. 107 * 108 * 4) Transaction commit 109 * Any record in X's swapped_blocks gets removed, since there is no 110 * modification to the swapped subtrees, no need to trigger heavy qgroup 111 * subtree rescan for them. 112 */ 113 114 /* 115 * These flags share the flags field of the btrfs_qgroup_status_item with the 116 * persisted flags defined in btrfs_tree.h. 117 * 118 * To minimize the chance of collision with new persisted status flags, these 119 * count backwards from the MSB. 120 */ 121 #define BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN (1ULL << 63) 122 #define BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING (1ULL << 62) 123 124 #define BTRFS_QGROUP_DROP_SUBTREE_THRES_DEFAULT (3) 125 126 /* 127 * Record a dirty extent, and info qgroup to update quota on it 128 */ 129 struct btrfs_qgroup_extent_record { 130 u64 bytenr; 131 u64 num_bytes; 132 133 /* 134 * For qgroup reserved data space freeing. 135 * 136 * @data_rsv_refroot and @data_rsv will be recorded after 137 * BTRFS_ADD_DELAYED_EXTENT is called. 138 * And will be used to free reserved qgroup space at 139 * transaction commit time. 140 */ 141 u32 data_rsv; /* reserved data space needs to be freed */ 142 u64 data_rsv_refroot; /* which root the reserved data belongs to */ 143 struct ulist *old_roots; 144 }; 145 146 struct btrfs_qgroup_swapped_block { 147 struct rb_node node; 148 149 int level; 150 bool trace_leaf; 151 152 /* bytenr/generation of the tree block in subvolume tree after swap */ 153 u64 subvol_bytenr; 154 u64 subvol_generation; 155 156 /* bytenr/generation of the tree block in reloc tree after swap */ 157 u64 reloc_bytenr; 158 u64 reloc_generation; 159 160 u64 last_snapshot; 161 struct btrfs_key first_key; 162 }; 163 164 /* 165 * Qgroup reservation types: 166 * 167 * DATA: 168 * space reserved for data 169 * 170 * META_PERTRANS: 171 * Space reserved for metadata (per-transaction) 172 * Due to the fact that qgroup data is only updated at transaction commit 173 * time, reserved space for metadata must be kept until transaction 174 * commits. 175 * Any metadata reserved that are used in btrfs_start_transaction() should 176 * be of this type. 177 * 178 * META_PREALLOC: 179 * There are cases where metadata space is reserved before starting 180 * transaction, and then btrfs_join_transaction() to get a trans handle. 181 * Any metadata reserved for such usage should be of this type. 182 * And after join_transaction() part (or all) of such reservation should 183 * be converted into META_PERTRANS. 184 */ 185 enum btrfs_qgroup_rsv_type { 186 BTRFS_QGROUP_RSV_DATA, 187 BTRFS_QGROUP_RSV_META_PERTRANS, 188 BTRFS_QGROUP_RSV_META_PREALLOC, 189 BTRFS_QGROUP_RSV_LAST, 190 }; 191 192 /* 193 * Represents how many bytes we have reserved for this qgroup. 194 * 195 * Each type should have different reservation behavior. 196 * E.g, data follows its io_tree flag modification, while 197 * *currently* meta is just reserve-and-clear during transaction. 198 * 199 * TODO: Add new type for reservation which can survive transaction commit. 200 * Current metadata reservation behavior is not suitable for such case. 201 */ 202 struct btrfs_qgroup_rsv { 203 u64 values[BTRFS_QGROUP_RSV_LAST]; 204 }; 205 206 /* 207 * one struct for each qgroup, organized in fs_info->qgroup_tree. 208 */ 209 struct btrfs_qgroup { 210 u64 qgroupid; 211 212 /* 213 * state 214 */ 215 u64 rfer; /* referenced */ 216 u64 rfer_cmpr; /* referenced compressed */ 217 u64 excl; /* exclusive */ 218 u64 excl_cmpr; /* exclusive compressed */ 219 220 /* 221 * limits 222 */ 223 u64 lim_flags; /* which limits are set */ 224 u64 max_rfer; 225 u64 max_excl; 226 u64 rsv_rfer; 227 u64 rsv_excl; 228 229 /* 230 * reservation tracking 231 */ 232 struct btrfs_qgroup_rsv rsv; 233 234 /* 235 * lists 236 */ 237 struct list_head groups; /* groups this group is member of */ 238 struct list_head members; /* groups that are members of this group */ 239 struct list_head dirty; /* dirty groups */ 240 241 /* 242 * For qgroup iteration usage. 243 * 244 * The iteration list should always be empty until qgroup_iterator_add() 245 * is called. And should be reset to empty after the iteration is 246 * finished. 247 */ 248 struct list_head iterator; 249 250 /* 251 * For nested iterator usage. 252 * 253 * Here we support at most one level of nested iterator calls like: 254 * 255 * LIST_HEAD(all_qgroups); 256 * { 257 * LIST_HEAD(local_qgroups); 258 * qgroup_iterator_add(local_qgroups, qg); 259 * qgroup_iterator_nested_add(all_qgroups, qg); 260 * do_some_work(local_qgroups); 261 * qgroup_iterator_clean(local_qgroups); 262 * } 263 * do_some_work(all_qgroups); 264 * qgroup_iterator_nested_clean(all_qgroups); 265 */ 266 struct list_head nested_iterator; 267 struct rb_node node; /* tree of qgroups */ 268 269 /* 270 * temp variables for accounting operations 271 * Refer to qgroup_shared_accounting() for details. 272 */ 273 u64 old_refcnt; 274 u64 new_refcnt; 275 276 /* 277 * Sysfs kobjectid 278 */ 279 struct kobject kobj; 280 }; 281 282 /* Glue structure to represent the relations between qgroups. */ 283 struct btrfs_qgroup_list { 284 struct list_head next_group; 285 struct list_head next_member; 286 struct btrfs_qgroup *group; 287 struct btrfs_qgroup *member; 288 }; 289 290 struct btrfs_squota_delta { 291 /* The fstree root this delta counts against. */ 292 u64 root; 293 /* The number of bytes in the extent being counted. */ 294 u64 num_bytes; 295 /* The generation the extent was created in. */ 296 u64 generation; 297 /* Whether we are using or freeing the extent. */ 298 bool is_inc; 299 /* Whether the extent is data or metadata. */ 300 bool is_data; 301 }; 302 303 static inline u64 btrfs_qgroup_subvolid(u64 qgroupid) 304 { 305 return (qgroupid & ((1ULL << BTRFS_QGROUP_LEVEL_SHIFT) - 1)); 306 } 307 308 /* 309 * For qgroup event trace points only 310 */ 311 enum { 312 ENUM_BIT(QGROUP_RESERVE), 313 ENUM_BIT(QGROUP_RELEASE), 314 ENUM_BIT(QGROUP_FREE), 315 }; 316 317 enum btrfs_qgroup_mode { 318 BTRFS_QGROUP_MODE_DISABLED, 319 BTRFS_QGROUP_MODE_FULL, 320 BTRFS_QGROUP_MODE_SIMPLE 321 }; 322 323 enum btrfs_qgroup_mode btrfs_qgroup_mode(const struct btrfs_fs_info *fs_info); 324 bool btrfs_qgroup_enabled(const struct btrfs_fs_info *fs_info); 325 bool btrfs_qgroup_full_accounting(const struct btrfs_fs_info *fs_info); 326 int btrfs_quota_enable(struct btrfs_fs_info *fs_info, 327 struct btrfs_ioctl_quota_ctl_args *quota_ctl_args); 328 int btrfs_quota_disable(struct btrfs_fs_info *fs_info); 329 int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info); 330 void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info); 331 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info, 332 bool interruptible); 333 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst, 334 struct btrfs_qgroup_list *prealloc); 335 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, 336 u64 dst); 337 int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid); 338 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid); 339 int btrfs_qgroup_cleanup_dropped_subvolume(struct btrfs_fs_info *fs_info, u64 subvolid); 340 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid, 341 struct btrfs_qgroup_limit *limit); 342 int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info); 343 void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info); 344 345 int btrfs_qgroup_trace_extent_nolock( 346 struct btrfs_fs_info *fs_info, 347 struct btrfs_delayed_ref_root *delayed_refs, 348 struct btrfs_qgroup_extent_record *record); 349 int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans, 350 struct btrfs_qgroup_extent_record *qrecord); 351 int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr, 352 u64 num_bytes); 353 int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans, 354 struct extent_buffer *eb); 355 int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans, 356 struct extent_buffer *root_eb, 357 u64 root_gen, int root_level); 358 int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr, 359 u64 num_bytes, struct ulist *old_roots, 360 struct ulist *new_roots); 361 int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans); 362 int btrfs_run_qgroups(struct btrfs_trans_handle *trans); 363 int btrfs_qgroup_check_inherit(struct btrfs_fs_info *fs_info, 364 struct btrfs_qgroup_inherit *inherit, 365 size_t size); 366 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, 367 u64 objectid, u64 inode_rootid, 368 struct btrfs_qgroup_inherit *inherit); 369 void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info, 370 u64 ref_root, u64 num_bytes, 371 enum btrfs_qgroup_rsv_type type); 372 373 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 374 int btrfs_verify_qgroup_counts(const struct btrfs_fs_info *fs_info, u64 qgroupid, 375 u64 rfer, u64 excl); 376 #endif 377 378 /* New io_tree based accurate qgroup reserve API */ 379 int btrfs_qgroup_reserve_data(struct btrfs_inode *inode, 380 struct extent_changeset **reserved, u64 start, u64 len); 381 int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released); 382 int btrfs_qgroup_free_data(struct btrfs_inode *inode, 383 struct extent_changeset *reserved, u64 start, 384 u64 len, u64 *freed); 385 int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, 386 enum btrfs_qgroup_rsv_type type, bool enforce); 387 int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, 388 enum btrfs_qgroup_rsv_type type, bool enforce, 389 bool noflush); 390 /* Reserve metadata space for pertrans and prealloc type */ 391 static inline int btrfs_qgroup_reserve_meta_pertrans(struct btrfs_root *root, 392 int num_bytes, bool enforce) 393 { 394 return __btrfs_qgroup_reserve_meta(root, num_bytes, 395 BTRFS_QGROUP_RSV_META_PERTRANS, 396 enforce, false); 397 } 398 static inline int btrfs_qgroup_reserve_meta_prealloc(struct btrfs_root *root, 399 int num_bytes, bool enforce, 400 bool noflush) 401 { 402 return __btrfs_qgroup_reserve_meta(root, num_bytes, 403 BTRFS_QGROUP_RSV_META_PREALLOC, 404 enforce, noflush); 405 } 406 407 void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes, 408 enum btrfs_qgroup_rsv_type type); 409 410 /* Free per-transaction meta reservation for error handling */ 411 static inline void btrfs_qgroup_free_meta_pertrans(struct btrfs_root *root, 412 int num_bytes) 413 { 414 __btrfs_qgroup_free_meta(root, num_bytes, 415 BTRFS_QGROUP_RSV_META_PERTRANS); 416 } 417 418 /* Pre-allocated meta reservation can be freed at need */ 419 static inline void btrfs_qgroup_free_meta_prealloc(struct btrfs_root *root, 420 int num_bytes) 421 { 422 __btrfs_qgroup_free_meta(root, num_bytes, 423 BTRFS_QGROUP_RSV_META_PREALLOC); 424 } 425 426 void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root); 427 void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes); 428 void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode); 429 430 /* btrfs_qgroup_swapped_blocks related functions */ 431 void btrfs_qgroup_init_swapped_blocks( 432 struct btrfs_qgroup_swapped_blocks *swapped_blocks); 433 434 void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root); 435 int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans, 436 struct btrfs_root *subvol_root, 437 struct btrfs_block_group *bg, 438 struct extent_buffer *subvol_parent, int subvol_slot, 439 struct extent_buffer *reloc_parent, int reloc_slot, 440 u64 last_snapshot); 441 int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans, 442 struct btrfs_root *root, struct extent_buffer *eb); 443 void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans); 444 bool btrfs_check_quota_leak(const struct btrfs_fs_info *fs_info); 445 void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes); 446 int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info, 447 const struct btrfs_squota_delta *delta); 448 449 #endif 450