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 struct btrfs_transaction; 26 struct btrfs_block_group; 27 struct btrfs_qgroup_swapped_blocks; 28 29 /* 30 * Btrfs qgroup overview 31 * 32 * Btrfs qgroup splits into 3 main part: 33 * 1) Reserve 34 * Reserve metadata/data space for incoming operations 35 * Affect how qgroup limit works 36 * 37 * 2) Trace 38 * Tell btrfs qgroup to trace dirty extents. 39 * 40 * Dirty extents including: 41 * - Newly allocated extents 42 * - Extents going to be deleted (in this trans) 43 * - Extents whose owner is going to be modified 44 * 45 * This is the main part affects whether qgroup numbers will stay 46 * consistent. 47 * Btrfs qgroup can trace clean extents and won't cause any problem, 48 * but it will consume extra CPU time, it should be avoided if possible. 49 * 50 * 3) Account 51 * Btrfs qgroup will updates its numbers, based on dirty extents traced 52 * in previous step. 53 * 54 * Normally at qgroup rescan and transaction commit time. 55 */ 56 57 /* 58 * Special performance optimization for balance. 59 * 60 * For balance, we need to swap subtree of subvolume and reloc trees. 61 * In theory, we need to trace all subtree blocks of both subvolume and reloc 62 * trees, since their owner has changed during such swap. 63 * 64 * However since balance has ensured that both subtrees are containing the 65 * same contents and have the same tree structures, such swap won't cause 66 * qgroup number change. 67 * 68 * But there is a race window between subtree swap and transaction commit, 69 * during that window, if we increase/decrease tree level or merge/split tree 70 * blocks, we still need to trace the original subtrees. 71 * 72 * So for balance, we use a delayed subtree tracing, whose workflow is: 73 * 74 * 1) Record the subtree root block get swapped. 75 * 76 * During subtree swap: 77 * O = Old tree blocks 78 * N = New tree blocks 79 * reloc tree subvolume tree X 80 * Root Root 81 * / \ / \ 82 * NA OB OA OB 83 * / | | \ / | | \ 84 * NC ND OE OF OC OD OE OF 85 * 86 * In this case, NA and OA are going to be swapped, record (NA, OA) into 87 * subvolume tree X. 88 * 89 * 2) After subtree swap. 90 * reloc tree subvolume tree X 91 * Root Root 92 * / \ / \ 93 * OA OB NA OB 94 * / | | \ / | | \ 95 * OC OD OE OF NC ND OE OF 96 * 97 * 3a) COW happens for OB 98 * If we are going to COW tree block OB, we check OB's bytenr against 99 * tree X's swapped_blocks structure. 100 * If it doesn't fit any, nothing will happen. 101 * 102 * 3b) COW happens for NA 103 * Check NA's bytenr against tree X's swapped_blocks, and get a hit. 104 * Then we do subtree scan on both subtrees OA and NA. 105 * Resulting 6 tree blocks to be scanned (OA, OC, OD, NA, NC, ND). 106 * 107 * Then no matter what we do to subvolume tree X, qgroup numbers will 108 * still be correct. 109 * Then NA's record gets removed from X's swapped_blocks. 110 * 111 * 4) Transaction commit 112 * Any record in X's swapped_blocks gets removed, since there is no 113 * modification to the swapped subtrees, no need to trigger heavy qgroup 114 * subtree rescan for them. 115 */ 116 117 /* 118 * These flags share the flags field of the btrfs_qgroup_status_item with the 119 * persisted flags defined in btrfs_tree.h. 120 * 121 * To minimize the chance of collision with new persisted status flags, these 122 * count backwards from the MSB. 123 */ 124 #define BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN (1ULL << 63) 125 #define BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING (1ULL << 62) 126 127 #define BTRFS_QGROUP_DROP_SUBTREE_THRES_DEFAULT (3) 128 129 /* 130 * Record a dirty extent, and info qgroup to update quota on it 131 */ 132 struct btrfs_qgroup_extent_record { 133 /* 134 * The bytenr of the extent is given by its index in the dirty_extents 135 * xarray of struct btrfs_delayed_ref_root left shifted by 136 * fs_info->sectorsize_bits. 137 */ 138 139 u64 num_bytes; 140 141 /* 142 * For qgroup reserved data space freeing. 143 * 144 * @data_rsv_refroot and @data_rsv will be recorded after 145 * BTRFS_ADD_DELAYED_EXTENT is called. 146 * And will be used to free reserved qgroup space at 147 * transaction commit time. 148 */ 149 u32 data_rsv; /* reserved data space needs to be freed */ 150 u64 data_rsv_refroot; /* which root the reserved data belongs to */ 151 struct ulist *old_roots; 152 }; 153 154 struct btrfs_qgroup_swapped_block { 155 struct rb_node node; 156 157 int level; 158 bool trace_leaf; 159 160 /* bytenr/generation of the tree block in subvolume tree after swap */ 161 u64 subvol_bytenr; 162 u64 subvol_generation; 163 164 /* bytenr/generation of the tree block in reloc tree after swap */ 165 u64 reloc_bytenr; 166 u64 reloc_generation; 167 168 u64 last_snapshot; 169 struct btrfs_key first_key; 170 }; 171 172 /* 173 * Qgroup reservation types: 174 * 175 * DATA: 176 * space reserved for data 177 * 178 * META_PERTRANS: 179 * Space reserved for metadata (per-transaction) 180 * Due to the fact that qgroup data is only updated at transaction commit 181 * time, reserved space for metadata must be kept until transaction 182 * commits. 183 * Any metadata reserved that are used in btrfs_start_transaction() should 184 * be of this type. 185 * 186 * META_PREALLOC: 187 * There are cases where metadata space is reserved before starting 188 * transaction, and then btrfs_join_transaction() to get a trans handle. 189 * Any metadata reserved for such usage should be of this type. 190 * And after join_transaction() part (or all) of such reservation should 191 * be converted into META_PERTRANS. 192 */ 193 enum btrfs_qgroup_rsv_type { 194 BTRFS_QGROUP_RSV_DATA, 195 BTRFS_QGROUP_RSV_META_PERTRANS, 196 BTRFS_QGROUP_RSV_META_PREALLOC, 197 BTRFS_QGROUP_RSV_LAST, 198 }; 199 200 /* 201 * Represents how many bytes we have reserved for this qgroup. 202 * 203 * Each type should have different reservation behavior. 204 * E.g, data follows its io_tree flag modification, while 205 * *currently* meta is just reserve-and-clear during transaction. 206 * 207 * TODO: Add new type for reservation which can survive transaction commit. 208 * Current metadata reservation behavior is not suitable for such case. 209 */ 210 struct btrfs_qgroup_rsv { 211 u64 values[BTRFS_QGROUP_RSV_LAST]; 212 }; 213 214 /* 215 * one struct for each qgroup, organized in fs_info->qgroup_tree. 216 */ 217 struct btrfs_qgroup { 218 u64 qgroupid; 219 220 /* 221 * state 222 */ 223 u64 rfer; /* referenced */ 224 u64 rfer_cmpr; /* referenced compressed */ 225 u64 excl; /* exclusive */ 226 u64 excl_cmpr; /* exclusive compressed */ 227 228 /* 229 * limits 230 */ 231 u64 lim_flags; /* which limits are set */ 232 u64 max_rfer; 233 u64 max_excl; 234 u64 rsv_rfer; 235 u64 rsv_excl; 236 237 /* 238 * reservation tracking 239 */ 240 struct btrfs_qgroup_rsv rsv; 241 242 /* 243 * lists 244 */ 245 struct list_head groups; /* groups this group is member of */ 246 struct list_head members; /* groups that are members of this group */ 247 struct list_head dirty; /* dirty groups */ 248 249 /* 250 * For qgroup iteration usage. 251 * 252 * The iteration list should always be empty until qgroup_iterator_add() 253 * is called. And should be reset to empty after the iteration is 254 * finished. 255 */ 256 struct list_head iterator; 257 258 /* 259 * For nested iterator usage. 260 * 261 * Here we support at most one level of nested iterator calls like: 262 * 263 * LIST_HEAD(all_qgroups); 264 * { 265 * LIST_HEAD(local_qgroups); 266 * qgroup_iterator_add(local_qgroups, qg); 267 * qgroup_iterator_nested_add(all_qgroups, qg); 268 * do_some_work(local_qgroups); 269 * qgroup_iterator_clean(local_qgroups); 270 * } 271 * do_some_work(all_qgroups); 272 * qgroup_iterator_nested_clean(all_qgroups); 273 */ 274 struct list_head nested_iterator; 275 struct rb_node node; /* tree of qgroups */ 276 277 /* 278 * temp variables for accounting operations 279 * Refer to qgroup_shared_accounting() for details. 280 */ 281 u64 old_refcnt; 282 u64 new_refcnt; 283 284 /* 285 * Sysfs kobjectid 286 */ 287 struct kobject kobj; 288 }; 289 290 /* Glue structure to represent the relations between qgroups. */ 291 struct btrfs_qgroup_list { 292 struct list_head next_group; 293 struct list_head next_member; 294 struct btrfs_qgroup *group; 295 struct btrfs_qgroup *member; 296 }; 297 298 struct btrfs_squota_delta { 299 /* The fstree root this delta counts against. */ 300 u64 root; 301 /* The number of bytes in the extent being counted. */ 302 u64 num_bytes; 303 /* The generation the extent was created in. */ 304 u64 generation; 305 /* Whether we are using or freeing the extent. */ 306 bool is_inc; 307 /* Whether the extent is data or metadata. */ 308 bool is_data; 309 }; 310 311 static inline u64 btrfs_qgroup_subvolid(u64 qgroupid) 312 { 313 return (qgroupid & ((1ULL << BTRFS_QGROUP_LEVEL_SHIFT) - 1)); 314 } 315 316 /* 317 * For qgroup event trace points only 318 */ 319 enum { 320 ENUM_BIT(QGROUP_RESERVE), 321 ENUM_BIT(QGROUP_RELEASE), 322 ENUM_BIT(QGROUP_FREE), 323 }; 324 325 enum btrfs_qgroup_mode { 326 BTRFS_QGROUP_MODE_DISABLED, 327 BTRFS_QGROUP_MODE_FULL, 328 BTRFS_QGROUP_MODE_SIMPLE 329 }; 330 331 enum btrfs_qgroup_mode btrfs_qgroup_mode(const struct btrfs_fs_info *fs_info); 332 bool btrfs_qgroup_enabled(const struct btrfs_fs_info *fs_info); 333 bool btrfs_qgroup_full_accounting(const struct btrfs_fs_info *fs_info); 334 int btrfs_quota_enable(struct btrfs_fs_info *fs_info, 335 struct btrfs_ioctl_quota_ctl_args *quota_ctl_args); 336 int btrfs_quota_disable(struct btrfs_fs_info *fs_info); 337 int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info); 338 void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info); 339 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info, 340 bool interruptible); 341 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst, 342 struct btrfs_qgroup_list *prealloc); 343 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, 344 u64 dst); 345 int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid); 346 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid); 347 int btrfs_qgroup_cleanup_dropped_subvolume(struct btrfs_fs_info *fs_info, u64 subvolid); 348 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid, 349 struct btrfs_qgroup_limit *limit); 350 int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info); 351 void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info); 352 353 int btrfs_qgroup_trace_extent_nolock( 354 struct btrfs_fs_info *fs_info, 355 struct btrfs_delayed_ref_root *delayed_refs, 356 struct btrfs_qgroup_extent_record *record, 357 u64 bytenr); 358 int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans, 359 struct btrfs_qgroup_extent_record *qrecord, 360 u64 bytenr); 361 int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr, 362 u64 num_bytes); 363 int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans, 364 struct extent_buffer *eb); 365 int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans, 366 struct extent_buffer *root_eb, 367 u64 root_gen, int root_level); 368 int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr, 369 u64 num_bytes, struct ulist *old_roots, 370 struct ulist *new_roots); 371 int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans); 372 int btrfs_run_qgroups(struct btrfs_trans_handle *trans); 373 int btrfs_qgroup_check_inherit(struct btrfs_fs_info *fs_info, 374 struct btrfs_qgroup_inherit *inherit, 375 size_t size); 376 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, 377 u64 objectid, u64 inode_rootid, 378 struct btrfs_qgroup_inherit *inherit); 379 void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info, 380 u64 ref_root, u64 num_bytes, 381 enum btrfs_qgroup_rsv_type type); 382 383 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 384 int btrfs_verify_qgroup_counts(const struct btrfs_fs_info *fs_info, u64 qgroupid, 385 u64 rfer, u64 excl); 386 #endif 387 388 /* New io_tree based accurate qgroup reserve API */ 389 int btrfs_qgroup_reserve_data(struct btrfs_inode *inode, 390 struct extent_changeset **reserved, u64 start, u64 len); 391 int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released); 392 int btrfs_qgroup_free_data(struct btrfs_inode *inode, 393 struct extent_changeset *reserved, u64 start, 394 u64 len, u64 *freed); 395 int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, 396 enum btrfs_qgroup_rsv_type type, bool enforce); 397 int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, 398 enum btrfs_qgroup_rsv_type type, bool enforce, 399 bool noflush); 400 /* Reserve metadata space for pertrans and prealloc type */ 401 static inline int btrfs_qgroup_reserve_meta_pertrans(struct btrfs_root *root, 402 int num_bytes, bool enforce) 403 { 404 return __btrfs_qgroup_reserve_meta(root, num_bytes, 405 BTRFS_QGROUP_RSV_META_PERTRANS, 406 enforce, false); 407 } 408 static inline int btrfs_qgroup_reserve_meta_prealloc(struct btrfs_root *root, 409 int num_bytes, bool enforce, 410 bool noflush) 411 { 412 return __btrfs_qgroup_reserve_meta(root, num_bytes, 413 BTRFS_QGROUP_RSV_META_PREALLOC, 414 enforce, noflush); 415 } 416 417 void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes, 418 enum btrfs_qgroup_rsv_type type); 419 420 /* Free per-transaction meta reservation for error handling */ 421 static inline void btrfs_qgroup_free_meta_pertrans(struct btrfs_root *root, 422 int num_bytes) 423 { 424 __btrfs_qgroup_free_meta(root, num_bytes, 425 BTRFS_QGROUP_RSV_META_PERTRANS); 426 } 427 428 /* Pre-allocated meta reservation can be freed at need */ 429 static inline void btrfs_qgroup_free_meta_prealloc(struct btrfs_root *root, 430 int num_bytes) 431 { 432 __btrfs_qgroup_free_meta(root, num_bytes, 433 BTRFS_QGROUP_RSV_META_PREALLOC); 434 } 435 436 void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root); 437 void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes); 438 void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode); 439 440 /* btrfs_qgroup_swapped_blocks related functions */ 441 void btrfs_qgroup_init_swapped_blocks( 442 struct btrfs_qgroup_swapped_blocks *swapped_blocks); 443 444 void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root); 445 int btrfs_qgroup_add_swapped_blocks(struct btrfs_root *subvol_root, 446 struct btrfs_block_group *bg, 447 struct extent_buffer *subvol_parent, int subvol_slot, 448 struct extent_buffer *reloc_parent, int reloc_slot, 449 u64 last_snapshot); 450 int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans, 451 struct btrfs_root *root, struct extent_buffer *eb); 452 void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans); 453 bool btrfs_check_quota_leak(const struct btrfs_fs_info *fs_info); 454 int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info, 455 const struct btrfs_squota_delta *delta); 456 457 #endif 458