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