fs/btrfs/qgroup.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2011 STRATO.  All rights reserved.
   4  */
   5
   6 #include <linux/sched.h>
   7 #include <linux/pagemap.h>
   8 #include <linux/writeback.h>
   9 #include <linux/blkdev.h>
  10 #include <linux/rbtree.h>
  11 #include <linux/slab.h>
  12 #include <linux/workqueue.h>
  13 #include <linux/btrfs.h>
  14 #include <linux/sizes.h>
  15
  16 #include "ctree.h"
  17 #include "transaction.h"
  18 #include "disk-io.h"
  19 #include "locking.h"
  20 #include "ulist.h"
  21 #include "backref.h"
  22 #include "extent_io.h"
  23 #include "qgroup.h"
  24
  25
  26 /* TODO XXX FIXME
  27  *  - subvol delete -> delete when ref goes to 0? delete limits also?
  28  *  - reorganize keys
  29  *  - compressed
  30  *  - sync
  31  *  - copy also limits on subvol creation
  32  *  - limit
  33  *  - caches for ulists
  34  *  - performance benchmarks
  35  *  - check all ioctl parameters
  36  */
  37
  38 /*
  39  * Helpers to access qgroup reservation
  40  *
  41  * Callers should ensure the lock context and type are valid
  42  */
  43
  44 static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup)
  45 {
  46         u64 ret = 0;
  47         int i;
  48
  49         for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
  50                 ret += qgroup->rsv.values[i];
  51
  52         return ret;
  53 }
  54
  55 #ifdef CONFIG_BTRFS_DEBUG
  56 static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type)
  57 {
  58         if (type == BTRFS_QGROUP_RSV_DATA)
  59                 return "data";
  60         if (type == BTRFS_QGROUP_RSV_META_PERTRANS)
  61                 return "meta_pertrans";
  62         if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
  63                 return "meta_prealloc";
  64         return NULL;
  65 }
  66 #endif
  67
  68 static void qgroup_rsv_add(struct btrfs_fs_info *fs_info,
  69                            struct btrfs_qgroup *qgroup, u64 num_bytes,
  70                            enum btrfs_qgroup_rsv_type type)
  71 {
  72         trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type);
  73         qgroup->rsv.values[type] += num_bytes;
  74 }
  75
  76 static void qgroup_rsv_release(struct btrfs_fs_info *fs_info,
  77                                struct btrfs_qgroup *qgroup, u64 num_bytes,
  78                                enum btrfs_qgroup_rsv_type type)
  79 {
  80         trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type);
  81         if (qgroup->rsv.values[type] >= num_bytes) {
  82                 qgroup->rsv.values[type] -= num_bytes;
  83                 return;
  84         }
  85 #ifdef CONFIG_BTRFS_DEBUG
  86         WARN_RATELIMIT(1,
  87                 "qgroup %llu %s reserved space underflow, have %llu to free %llu",
  88                 qgroup->qgroupid, qgroup_rsv_type_str(type),
  89                 qgroup->rsv.values[type], num_bytes);
  90 #endif
  91         qgroup->rsv.values[type] = 0;
  92 }
  93
  94 static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info,
  95                                      struct btrfs_qgroup *dest,
  96                                      struct btrfs_qgroup *src)
  97 {
  98         int i;
  99
 100         for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 101                 qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i);
 102 }
 103
 104 static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info,
 105                                          struct btrfs_qgroup *dest,
 106                                           struct btrfs_qgroup *src)
 107 {
 108         int i;
 109
 110         for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 111                 qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i);
 112 }
 113
 114 static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
 115                                            int mod)
 116 {
 117         if (qg->old_refcnt < seq)
 118                 qg->old_refcnt = seq;
 119         qg->old_refcnt += mod;
 120 }
 121
 122 static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
 123                                            int mod)
 124 {
 125         if (qg->new_refcnt < seq)
 126                 qg->new_refcnt = seq;
 127         qg->new_refcnt += mod;
 128 }
 129
 130 static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
 131 {
 132         if (qg->old_refcnt < seq)
 133                 return 0;
 134         return qg->old_refcnt - seq;
 135 }
 136
 137 static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
 138 {
 139         if (qg->new_refcnt < seq)
 140                 return 0;
 141         return qg->new_refcnt - seq;
 142 }
 143
 144 /*
 145  * glue structure to represent the relations between qgroups.
 146  */
 147 struct btrfs_qgroup_list {
 148         struct list_head next_group;
 149         struct list_head next_member;
 150         struct btrfs_qgroup *group;
 151         struct btrfs_qgroup *member;
 152 };
 153
 154 static inline u64 qgroup_to_aux(struct btrfs_qgroup *qg)
 155 {
 156         return (u64)(uintptr_t)qg;
 157 }
 158
 159 static inline struct btrfs_qgroup* unode_aux_to_qgroup(struct ulist_node *n)
 160 {
 161         return (struct btrfs_qgroup *)(uintptr_t)n->aux;
 162 }
 163
 164 static int
 165 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
 166                    int init_flags);
 167 static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 168
 169 /* must be called with qgroup_ioctl_lock held */
 170 static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
 171                                            u64 qgroupid)
 172 {
 173         struct rb_node *n = fs_info->qgroup_tree.rb_node;
 174         struct btrfs_qgroup *qgroup;
 175
 176         while (n) {
 177                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
 178                 if (qgroup->qgroupid < qgroupid)
 179                         n = n->rb_left;
 180                 else if (qgroup->qgroupid > qgroupid)
 181                         n = n->rb_right;
 182                 else
 183                         return qgroup;
 184         }
 185         return NULL;
 186 }
 187
 188 /* must be called with qgroup_lock held */
 189 static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
 190                                           u64 qgroupid)
 191 {
 192         struct rb_node **p = &fs_info->qgroup_tree.rb_node;
 193         struct rb_node *parent = NULL;
 194         struct btrfs_qgroup *qgroup;
 195
 196         while (*p) {
 197                 parent = *p;
 198                 qgroup = rb_entry(parent, struct btrfs_qgroup, node);
 199
 200                 if (qgroup->qgroupid < qgroupid)
 201                         p = &(*p)->rb_left;
 202                 else if (qgroup->qgroupid > qgroupid)
 203                         p = &(*p)->rb_right;
 204                 else
 205                         return qgroup;
 206         }
 207
 208         qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
 209         if (!qgroup)
 210                 return ERR_PTR(-ENOMEM);
 211
 212         qgroup->qgroupid = qgroupid;
 213         INIT_LIST_HEAD(&qgroup->groups);
 214         INIT_LIST_HEAD(&qgroup->members);
 215         INIT_LIST_HEAD(&qgroup->dirty);
 216
 217         rb_link_node(&qgroup->node, parent, p);
 218         rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
 219
 220         return qgroup;
 221 }
 222
 223 static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
 224 {
 225         struct btrfs_qgroup_list *list;
 226
 227         list_del(&qgroup->dirty);
 228         while (!list_empty(&qgroup->groups)) {
 229                 list = list_first_entry(&qgroup->groups,
 230                                         struct btrfs_qgroup_list, next_group);
 231                 list_del(&list->next_group);
 232                 list_del(&list->next_member);
 233                 kfree(list);
 234         }
 235
 236         while (!list_empty(&qgroup->members)) {
 237                 list = list_first_entry(&qgroup->members,
 238                                         struct btrfs_qgroup_list, next_member);
 239                 list_del(&list->next_group);
 240                 list_del(&list->next_member);
 241                 kfree(list);
 242         }
 243         kfree(qgroup);
 244 }
 245
 246 /* must be called with qgroup_lock held */
 247 static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
 248 {
 249         struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
 250
 251         if (!qgroup)
 252                 return -ENOENT;
 253
 254         rb_erase(&qgroup->node, &fs_info->qgroup_tree);
 255         __del_qgroup_rb(qgroup);
 256         return 0;
 257 }
 258
 259 /* must be called with qgroup_lock held */
 260 static int add_relation_rb(struct btrfs_fs_info *fs_info,
 261                            u64 memberid, u64 parentid)
 262 {
 263         struct btrfs_qgroup *member;
 264         struct btrfs_qgroup *parent;
 265         struct btrfs_qgroup_list *list;
 266
 267         member = find_qgroup_rb(fs_info, memberid);
 268         parent = find_qgroup_rb(fs_info, parentid);
 269         if (!member || !parent)
 270                 return -ENOENT;
 271
 272         list = kzalloc(sizeof(*list), GFP_ATOMIC);
 273         if (!list)
 274                 return -ENOMEM;
 275
 276         list->group = parent;
 277         list->member = member;
 278         list_add_tail(&list->next_group, &member->groups);
 279         list_add_tail(&list->next_member, &parent->members);
 280
 281         return 0;
 282 }
 283
 284 /* must be called with qgroup_lock held */
 285 static int del_relation_rb(struct btrfs_fs_info *fs_info,
 286                            u64 memberid, u64 parentid)
 287 {
 288         struct btrfs_qgroup *member;
 289         struct btrfs_qgroup *parent;
 290         struct btrfs_qgroup_list *list;
 291
 292         member = find_qgroup_rb(fs_info, memberid);
 293         parent = find_qgroup_rb(fs_info, parentid);
 294         if (!member || !parent)
 295                 return -ENOENT;
 296
 297         list_for_each_entry(list, &member->groups, next_group) {
 298                 if (list->group == parent) {
 299                         list_del(&list->next_group);
 300                         list_del(&list->next_member);
 301                         kfree(list);
 302                         return 0;
 303                 }
 304         }
 305         return -ENOENT;
 306 }
 307
 308 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 309 int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
 310                                u64 rfer, u64 excl)
 311 {
 312         struct btrfs_qgroup *qgroup;
 313
 314         qgroup = find_qgroup_rb(fs_info, qgroupid);
 315         if (!qgroup)
 316                 return -EINVAL;
 317         if (qgroup->rfer != rfer || qgroup->excl != excl)
 318                 return -EINVAL;
 319         return 0;
 320 }
 321 #endif
 322
 323 /*
 324  * The full config is read in one go, only called from open_ctree()
 325  * It doesn't use any locking, as at this point we're still single-threaded
 326  */
 327 int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
 328 {
 329         struct btrfs_key key;
 330         struct btrfs_key found_key;
 331         struct btrfs_root *quota_root = fs_info->quota_root;
 332         struct btrfs_path *path = NULL;
 333         struct extent_buffer *l;
 334         int slot;
 335         int ret = 0;
 336         u64 flags = 0;
 337         u64 rescan_progress = 0;
 338
 339         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
 340                 return 0;
 341
 342         fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 343         if (!fs_info->qgroup_ulist) {
 344                 ret = -ENOMEM;
 345                 goto out;
 346         }
 347
 348         path = btrfs_alloc_path();
 349         if (!path) {
 350                 ret = -ENOMEM;
 351                 goto out;
 352         }
 353
 354         /* default this to quota off, in case no status key is found */
 355         fs_info->qgroup_flags = 0;
 356
 357         /*
 358          * pass 1: read status, all qgroup infos and limits
 359          */
 360         key.objectid = 0;
 361         key.type = 0;
 362         key.offset = 0;
 363         ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
 364         if (ret)
 365                 goto out;
 366
 367         while (1) {
 368                 struct btrfs_qgroup *qgroup;
 369
 370                 slot = path->slots[0];
 371                 l = path->nodes[0];
 372                 btrfs_item_key_to_cpu(l, &found_key, slot);
 373
 374                 if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
 375                         struct btrfs_qgroup_status_item *ptr;
 376
 377                         ptr = btrfs_item_ptr(l, slot,
 378                                              struct btrfs_qgroup_status_item);
 379
 380                         if (btrfs_qgroup_status_version(l, ptr) !=
 381                             BTRFS_QGROUP_STATUS_VERSION) {
 382                                 btrfs_err(fs_info,
 383                                  "old qgroup version, quota disabled");
 384                                 goto out;
 385                         }
 386                         if (btrfs_qgroup_status_generation(l, ptr) !=
 387                             fs_info->generation) {
 388                                 flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 389                                 btrfs_err(fs_info,
 390                                         "qgroup generation mismatch, marked as inconsistent");
 391                         }
 392                         fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
 393                                                                           ptr);
 394                         rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
 395                         goto next1;
 396                 }
 397
 398                 if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
 399                     found_key.type != BTRFS_QGROUP_LIMIT_KEY)
 400                         goto next1;
 401
 402                 qgroup = find_qgroup_rb(fs_info, found_key.offset);
 403                 if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
 404                     (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
 405                         btrfs_err(fs_info, "inconsistent qgroup config");
 406                         flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 407                 }
 408                 if (!qgroup) {
 409                         qgroup = add_qgroup_rb(fs_info, found_key.offset);
 410                         if (IS_ERR(qgroup)) {
 411                                 ret = PTR_ERR(qgroup);
 412                                 goto out;
 413                         }
 414                 }
 415                 switch (found_key.type) {
 416                 case BTRFS_QGROUP_INFO_KEY: {
 417                         struct btrfs_qgroup_info_item *ptr;
 418
 419                         ptr = btrfs_item_ptr(l, slot,
 420                                              struct btrfs_qgroup_info_item);
 421                         qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
 422                         qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
 423                         qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
 424                         qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
 425                         /* generation currently unused */
 426                         break;
 427                 }
 428                 case BTRFS_QGROUP_LIMIT_KEY: {
 429                         struct btrfs_qgroup_limit_item *ptr;
 430
 431                         ptr = btrfs_item_ptr(l, slot,
 432                                              struct btrfs_qgroup_limit_item);
 433                         qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
 434                         qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
 435                         qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
 436                         qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
 437                         qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
 438                         break;
 439                 }
 440                 }
 441 next1:
 442                 ret = btrfs_next_item(quota_root, path);
 443                 if (ret < 0)
 444                         goto out;
 445                 if (ret)
 446                         break;
 447         }
 448         btrfs_release_path(path);
 449
 450         /*
 451          * pass 2: read all qgroup relations
 452          */
 453         key.objectid = 0;
 454         key.type = BTRFS_QGROUP_RELATION_KEY;
 455         key.offset = 0;
 456         ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
 457         if (ret)
 458                 goto out;
 459         while (1) {
 460                 slot = path->slots[0];
 461                 l = path->nodes[0];
 462                 btrfs_item_key_to_cpu(l, &found_key, slot);
 463
 464                 if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
 465                         goto next2;
 466
 467                 if (found_key.objectid > found_key.offset) {
 468                         /* parent <- member, not needed to build config */
 469                         /* FIXME should we omit the key completely? */
 470                         goto next2;
 471                 }
 472
 473                 ret = add_relation_rb(fs_info, found_key.objectid,
 474                                       found_key.offset);
 475                 if (ret == -ENOENT) {
 476                         btrfs_warn(fs_info,
 477                                 "orphan qgroup relation 0x%llx->0x%llx",
 478                                 found_key.objectid, found_key.offset);
 479                         ret = 0;        /* ignore the error */
 480                 }
 481                 if (ret)
 482                         goto out;
 483 next2:
 484                 ret = btrfs_next_item(quota_root, path);
 485                 if (ret < 0)
 486                         goto out;
 487                 if (ret)
 488                         break;
 489         }
 490 out:
 491         fs_info->qgroup_flags |= flags;
 492         if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
 493                 clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
 494         else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
 495                  ret >= 0)
 496                 ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
 497         btrfs_free_path(path);
 498
 499         if (ret < 0) {
 500                 ulist_free(fs_info->qgroup_ulist);
 501                 fs_info->qgroup_ulist = NULL;
 502                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
 503         }
 504
 505         return ret < 0 ? ret : 0;
 506 }
 507
 508 /*
 509  * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
 510  * first two are in single-threaded paths.And for the third one, we have set
 511  * quota_root to be null with qgroup_lock held before, so it is safe to clean
 512  * up the in-memory structures without qgroup_lock held.
 513  */
 514 void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
 515 {
 516         struct rb_node *n;
 517         struct btrfs_qgroup *qgroup;
 518
 519         while ((n = rb_first(&fs_info->qgroup_tree))) {
 520                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
 521                 rb_erase(n, &fs_info->qgroup_tree);
 522                 __del_qgroup_rb(qgroup);
 523         }
 524         /*
 525          * We call btrfs_free_qgroup_config() when unmounting
 526          * filesystem and disabling quota, so we set qgroup_ulist
 527          * to be null here to avoid double free.
 528          */
 529         ulist_free(fs_info->qgroup_ulist);
 530         fs_info->qgroup_ulist = NULL;
 531 }
 532
 533 static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 534                                     u64 dst)
 535 {
 536         int ret;
 537         struct btrfs_root *quota_root = trans->fs_info->quota_root;
 538         struct btrfs_path *path;
 539         struct btrfs_key key;
 540
 541         path = btrfs_alloc_path();
 542         if (!path)
 543                 return -ENOMEM;
 544
 545         key.objectid = src;
 546         key.type = BTRFS_QGROUP_RELATION_KEY;
 547         key.offset = dst;
 548
 549         ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
 550
 551         btrfs_mark_buffer_dirty(path->nodes[0]);
 552
 553         btrfs_free_path(path);
 554         return ret;
 555 }
 556
 557 static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 558                                     u64 dst)
 559 {
 560         int ret;
 561         struct btrfs_root *quota_root = trans->fs_info->quota_root;
 562         struct btrfs_path *path;
 563         struct btrfs_key key;
 564
 565         path = btrfs_alloc_path();
 566         if (!path)
 567                 return -ENOMEM;
 568
 569         key.objectid = src;
 570         key.type = BTRFS_QGROUP_RELATION_KEY;
 571         key.offset = dst;
 572
 573         ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 574         if (ret < 0)
 575                 goto out;
 576
 577         if (ret > 0) {
 578                 ret = -ENOENT;
 579                 goto out;
 580         }
 581
 582         ret = btrfs_del_item(trans, quota_root, path);
 583 out:
 584         btrfs_free_path(path);
 585         return ret;
 586 }
 587
 588 static int add_qgroup_item(struct btrfs_trans_handle *trans,
 589                            struct btrfs_root *quota_root, u64 qgroupid)
 590 {
 591         int ret;
 592         struct btrfs_path *path;
 593         struct btrfs_qgroup_info_item *qgroup_info;
 594         struct btrfs_qgroup_limit_item *qgroup_limit;
 595         struct extent_buffer *leaf;
 596         struct btrfs_key key;
 597
 598         if (btrfs_is_testing(quota_root->fs_info))
 599                 return 0;
 600
 601         path = btrfs_alloc_path();
 602         if (!path)
 603                 return -ENOMEM;
 604
 605         key.objectid = 0;
 606         key.type = BTRFS_QGROUP_INFO_KEY;
 607         key.offset = qgroupid;
 608
 609         /*
 610          * Avoid a transaction abort by catching -EEXIST here. In that
 611          * case, we proceed by re-initializing the existing structure
 612          * on disk.
 613          */
 614
 615         ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 616                                       sizeof(*qgroup_info));
 617         if (ret && ret != -EEXIST)
 618                 goto out;
 619
 620         leaf = path->nodes[0];
 621         qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
 622                                  struct btrfs_qgroup_info_item);
 623         btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
 624         btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
 625         btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
 626         btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
 627         btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
 628
 629         btrfs_mark_buffer_dirty(leaf);
 630
 631         btrfs_release_path(path);
 632
 633         key.type = BTRFS_QGROUP_LIMIT_KEY;
 634         ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 635                                       sizeof(*qgroup_limit));
 636         if (ret && ret != -EEXIST)
 637                 goto out;
 638
 639         leaf = path->nodes[0];
 640         qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
 641                                   struct btrfs_qgroup_limit_item);
 642         btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
 643         btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
 644         btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
 645         btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
 646         btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
 647
 648         btrfs_mark_buffer_dirty(leaf);
 649
 650         ret = 0;
 651 out:
 652         btrfs_free_path(path);
 653         return ret;
 654 }
 655
 656 static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid)
 657 {
 658         int ret;
 659         struct btrfs_root *quota_root = trans->fs_info->quota_root;
 660         struct btrfs_path *path;
 661         struct btrfs_key key;
 662
 663         path = btrfs_alloc_path();
 664         if (!path)
 665                 return -ENOMEM;
 666
 667         key.objectid = 0;
 668         key.type = BTRFS_QGROUP_INFO_KEY;
 669         key.offset = qgroupid;
 670         ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 671         if (ret < 0)
 672                 goto out;
 673
 674         if (ret > 0) {
 675                 ret = -ENOENT;
 676                 goto out;
 677         }
 678
 679         ret = btrfs_del_item(trans, quota_root, path);
 680         if (ret)
 681                 goto out;
 682
 683         btrfs_release_path(path);
 684
 685         key.type = BTRFS_QGROUP_LIMIT_KEY;
 686         ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 687         if (ret < 0)
 688                 goto out;
 689
 690         if (ret > 0) {
 691                 ret = -ENOENT;
 692                 goto out;
 693         }
 694
 695         ret = btrfs_del_item(trans, quota_root, path);
 696
 697 out:
 698         btrfs_free_path(path);
 699         return ret;
 700 }
 701
 702 static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
 703                                     struct btrfs_qgroup *qgroup)
 704 {
 705         struct btrfs_root *quota_root = trans->fs_info->quota_root;
 706         struct btrfs_path *path;
 707         struct btrfs_key key;
 708         struct extent_buffer *l;
 709         struct btrfs_qgroup_limit_item *qgroup_limit;
 710         int ret;
 711         int slot;
 712
 713         key.objectid = 0;
 714         key.type = BTRFS_QGROUP_LIMIT_KEY;
 715         key.offset = qgroup->qgroupid;
 716
 717         path = btrfs_alloc_path();
 718         if (!path)
 719                 return -ENOMEM;
 720
 721         ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 722         if (ret > 0)
 723                 ret = -ENOENT;
 724
 725         if (ret)
 726                 goto out;
 727
 728         l = path->nodes[0];
 729         slot = path->slots[0];
 730         qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
 731         btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
 732         btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
 733         btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
 734         btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
 735         btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
 736
 737         btrfs_mark_buffer_dirty(l);
 738
 739 out:
 740         btrfs_free_path(path);
 741         return ret;
 742 }
 743
 744 static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
 745                                    struct btrfs_qgroup *qgroup)
 746 {
 747         struct btrfs_fs_info *fs_info = trans->fs_info;
 748         struct btrfs_root *quota_root = fs_info->quota_root;
 749         struct btrfs_path *path;
 750         struct btrfs_key key;
 751         struct extent_buffer *l;
 752         struct btrfs_qgroup_info_item *qgroup_info;
 753         int ret;
 754         int slot;
 755
 756         if (btrfs_is_testing(fs_info))
 757                 return 0;
 758
 759         key.objectid = 0;
 760         key.type = BTRFS_QGROUP_INFO_KEY;
 761         key.offset = qgroup->qgroupid;
 762
 763         path = btrfs_alloc_path();
 764         if (!path)
 765                 return -ENOMEM;
 766
 767         ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 768         if (ret > 0)
 769                 ret = -ENOENT;
 770
 771         if (ret)
 772                 goto out;
 773
 774         l = path->nodes[0];
 775         slot = path->slots[0];
 776         qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 777         btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 778         btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 779         btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 780         btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 781         btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 782
 783         btrfs_mark_buffer_dirty(l);
 784
 785 out:
 786         btrfs_free_path(path);
 787         return ret;
 788 }
 789
 790 static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
 791 {
 792         struct btrfs_fs_info *fs_info = trans->fs_info;
 793         struct btrfs_root *quota_root = fs_info->quota_root;
 794         struct btrfs_path *path;
 795         struct btrfs_key key;
 796         struct extent_buffer *l;
 797         struct btrfs_qgroup_status_item *ptr;
 798         int ret;
 799         int slot;
 800
 801         key.objectid = 0;
 802         key.type = BTRFS_QGROUP_STATUS_KEY;
 803         key.offset = 0;
 804
 805         path = btrfs_alloc_path();
 806         if (!path)
 807                 return -ENOMEM;
 808
 809         ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 810         if (ret > 0)
 811                 ret = -ENOENT;
 812
 813         if (ret)
 814                 goto out;
 815
 816         l = path->nodes[0];
 817         slot = path->slots[0];
 818         ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 819         btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
 820         btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 821         btrfs_set_qgroup_status_rescan(l, ptr,
 822                                 fs_info->qgroup_rescan_progress.objectid);
 823
 824         btrfs_mark_buffer_dirty(l);
 825
 826 out:
 827         btrfs_free_path(path);
 828         return ret;
 829 }
 830
 831 /*
 832  * called with qgroup_lock held
 833  */
 834 static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 835                                   struct btrfs_root *root)
 836 {
 837         struct btrfs_path *path;
 838         struct btrfs_key key;
 839         struct extent_buffer *leaf = NULL;
 840         int ret;
 841         int nr = 0;
 842
 843         path = btrfs_alloc_path();
 844         if (!path)
 845                 return -ENOMEM;
 846
 847         path->leave_spinning = 1;
 848
 849         key.objectid = 0;
 850         key.offset = 0;
 851         key.type = 0;
 852
 853         while (1) {
 854                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 855                 if (ret < 0)
 856                         goto out;
 857                 leaf = path->nodes[0];
 858                 nr = btrfs_header_nritems(leaf);
 859                 if (!nr)
 860                         break;
 861                 /*
 862                  * delete the leaf one by one
 863                  * since the whole tree is going
 864                  * to be deleted.
 865                  */
 866                 path->slots[0] = 0;
 867                 ret = btrfs_del_items(trans, root, path, 0, nr);
 868                 if (ret)
 869                         goto out;
 870
 871                 btrfs_release_path(path);
 872         }
 873         ret = 0;
 874 out:
 875         btrfs_free_path(path);
 876         return ret;
 877 }
 878
 879 int btrfs_quota_enable(struct btrfs_fs_info *fs_info)
 880 {
 881         struct btrfs_root *quota_root;
 882         struct btrfs_root *tree_root = fs_info->tree_root;
 883         struct btrfs_path *path = NULL;
 884         struct btrfs_qgroup_status_item *ptr;
 885         struct extent_buffer *leaf;
 886         struct btrfs_key key;
 887         struct btrfs_key found_key;
 888         struct btrfs_qgroup *qgroup = NULL;
 889         struct btrfs_trans_handle *trans = NULL;
 890         int ret = 0;
 891         int slot;
 892
 893         mutex_lock(&fs_info->qgroup_ioctl_lock);
 894         if (fs_info->quota_root)
 895                 goto out;
 896
 897         /*
 898          * 1 for quota root item
 899          * 1 for BTRFS_QGROUP_STATUS item
 900          *
 901          * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items
 902          * per subvolume. However those are not currently reserved since it
 903          * would be a lot of overkill.
 904          */
 905         trans = btrfs_start_transaction(tree_root, 2);
 906         if (IS_ERR(trans)) {
 907                 ret = PTR_ERR(trans);
 908                 trans = NULL;
 909                 goto out;
 910         }
 911
 912         fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 913         if (!fs_info->qgroup_ulist) {
 914                 ret = -ENOMEM;
 915                 btrfs_abort_transaction(trans, ret);
 916                 goto out;
 917         }
 918
 919         /*
 920          * initially create the quota tree
 921          */
 922         quota_root = btrfs_create_tree(trans, fs_info,
 923                                        BTRFS_QUOTA_TREE_OBJECTID);
 924         if (IS_ERR(quota_root)) {
 925                 ret =  PTR_ERR(quota_root);
 926                 btrfs_abort_transaction(trans, ret);
 927                 goto out;
 928         }
 929
 930         path = btrfs_alloc_path();
 931         if (!path) {
 932                 ret = -ENOMEM;
 933                 btrfs_abort_transaction(trans, ret);
 934                 goto out_free_root;
 935         }
 936
 937         key.objectid = 0;
 938         key.type = BTRFS_QGROUP_STATUS_KEY;
 939         key.offset = 0;
 940
 941         ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 942                                       sizeof(*ptr));
 943         if (ret) {
 944                 btrfs_abort_transaction(trans, ret);
 945                 goto out_free_path;
 946         }
 947
 948         leaf = path->nodes[0];
 949         ptr = btrfs_item_ptr(leaf, path->slots[0],
 950                                  struct btrfs_qgroup_status_item);
 951         btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
 952         btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
 953         fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
 954                                 BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 955         btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
 956         btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
 957
 958         btrfs_mark_buffer_dirty(leaf);
 959
 960         key.objectid = 0;
 961         key.type = BTRFS_ROOT_REF_KEY;
 962         key.offset = 0;
 963
 964         btrfs_release_path(path);
 965         ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
 966         if (ret > 0)
 967                 goto out_add_root;
 968         if (ret < 0) {
 969                 btrfs_abort_transaction(trans, ret);
 970                 goto out_free_path;
 971         }
 972
 973         while (1) {
 974                 slot = path->slots[0];
 975                 leaf = path->nodes[0];
 976                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
 977
 978                 if (found_key.type == BTRFS_ROOT_REF_KEY) {
 979                         ret = add_qgroup_item(trans, quota_root,
 980                                               found_key.offset);
 981                         if (ret) {
 982                                 btrfs_abort_transaction(trans, ret);
 983                                 goto out_free_path;
 984                         }
 985
 986                         qgroup = add_qgroup_rb(fs_info, found_key.offset);
 987                         if (IS_ERR(qgroup)) {
 988                                 ret = PTR_ERR(qgroup);
 989                                 btrfs_abort_transaction(trans, ret);
 990                                 goto out_free_path;
 991                         }
 992                 }
 993                 ret = btrfs_next_item(tree_root, path);
 994                 if (ret < 0) {
 995                         btrfs_abort_transaction(trans, ret);
 996                         goto out_free_path;
 997                 }
 998                 if (ret)
 999                         break;
1000         }
1001
1002 out_add_root:
1003         btrfs_release_path(path);
1004         ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
1005         if (ret) {
1006                 btrfs_abort_transaction(trans, ret);
1007                 goto out_free_path;
1008         }
1009
1010         qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
1011         if (IS_ERR(qgroup)) {
1012                 ret = PTR_ERR(qgroup);
1013                 btrfs_abort_transaction(trans, ret);
1014                 goto out_free_path;
1015         }
1016
1017         ret = btrfs_commit_transaction(trans);
1018         trans = NULL;
1019         if (ret)
1020                 goto out_free_path;
1021
1022         /*
1023          * Set quota enabled flag after committing the transaction, to avoid
1024          * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot
1025          * creation.
1026          */
1027         spin_lock(&fs_info->qgroup_lock);
1028         fs_info->quota_root = quota_root;
1029         set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1030         spin_unlock(&fs_info->qgroup_lock);
1031
1032         ret = qgroup_rescan_init(fs_info, 0, 1);
1033         if (!ret) {
1034                 qgroup_rescan_zero_tracking(fs_info);
1035                 btrfs_queue_work(fs_info->qgroup_rescan_workers,
1036                                  &fs_info->qgroup_rescan_work);
1037         }
1038
1039 out_free_path:
1040         btrfs_free_path(path);
1041 out_free_root:
1042         if (ret) {
1043                 free_extent_buffer(quota_root->node);
1044                 free_extent_buffer(quota_root->commit_root);
1045                 kfree(quota_root);
1046         }
1047 out:
1048         if (ret) {
1049                 ulist_free(fs_info->qgroup_ulist);
1050                 fs_info->qgroup_ulist = NULL;
1051                 if (trans)
1052                         btrfs_end_transaction(trans);
1053         }
1054         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1055         return ret;
1056 }
1057
1058 int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
1059 {
1060         struct btrfs_root *quota_root;
1061         struct btrfs_trans_handle *trans = NULL;
1062         int ret = 0;
1063
1064         mutex_lock(&fs_info->qgroup_ioctl_lock);
1065         if (!fs_info->quota_root)
1066                 goto out;
1067
1068         /*
1069          * 1 For the root item
1070          *
1071          * We should also reserve enough items for the quota tree deletion in
1072          * btrfs_clean_quota_tree but this is not done.
1073          */
1074         trans = btrfs_start_transaction(fs_info->tree_root, 1);
1075         if (IS_ERR(trans)) {
1076                 ret = PTR_ERR(trans);
1077                 goto out;
1078         }
1079
1080         clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1081         btrfs_qgroup_wait_for_completion(fs_info, false);
1082         spin_lock(&fs_info->qgroup_lock);
1083         quota_root = fs_info->quota_root;
1084         fs_info->quota_root = NULL;
1085         fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1086         spin_unlock(&fs_info->qgroup_lock);
1087
1088         btrfs_free_qgroup_config(fs_info);
1089
1090         ret = btrfs_clean_quota_tree(trans, quota_root);
1091         if (ret) {
1092                 btrfs_abort_transaction(trans, ret);
1093                 goto end_trans;
1094         }
1095
1096         ret = btrfs_del_root(trans, &quota_root->root_key);
1097         if (ret) {
1098                 btrfs_abort_transaction(trans, ret);
1099                 goto end_trans;
1100         }
1101
1102         list_del(&quota_root->dirty_list);
1103
1104         btrfs_tree_lock(quota_root->node);
1105         clean_tree_block(fs_info, quota_root->node);
1106         btrfs_tree_unlock(quota_root->node);
1107         btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
1108
1109         free_extent_buffer(quota_root->node);
1110         free_extent_buffer(quota_root->commit_root);
1111         kfree(quota_root);
1112
1113 end_trans:
1114         ret = btrfs_end_transaction(trans);
1115 out:
1116         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1117         return ret;
1118 }
1119
1120 static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1121                          struct btrfs_qgroup *qgroup)
1122 {
1123         if (list_empty(&qgroup->dirty))
1124                 list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1125 }
1126
1127 /*
1128  * The easy accounting, we're updating qgroup relationship whose child qgroup
1129  * only has exclusive extents.
1130  *
1131  * In this case, all exclusive extents will also be exclusive for parent, so
1132  * excl/rfer just get added/removed.
1133  *
1134  * So is qgroup reservation space, which should also be added/removed to
1135  * parent.
1136  * Or when child tries to release reservation space, parent will underflow its
1137  * reservation (for relationship adding case).
1138  *
1139  * Caller should hold fs_info->qgroup_lock.
1140  */
1141 static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1142                                     struct ulist *tmp, u64 ref_root,
1143                                     struct btrfs_qgroup *src, int sign)
1144 {
1145         struct btrfs_qgroup *qgroup;
1146         struct btrfs_qgroup_list *glist;
1147         struct ulist_node *unode;
1148         struct ulist_iterator uiter;
1149         u64 num_bytes = src->excl;
1150         int ret = 0;
1151
1152         qgroup = find_qgroup_rb(fs_info, ref_root);
1153         if (!qgroup)
1154                 goto out;
1155
1156         qgroup->rfer += sign * num_bytes;
1157         qgroup->rfer_cmpr += sign * num_bytes;
1158
1159         WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1160         qgroup->excl += sign * num_bytes;
1161         qgroup->excl_cmpr += sign * num_bytes;
1162
1163         if (sign > 0)
1164                 qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1165         else
1166                 qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1167
1168         qgroup_dirty(fs_info, qgroup);
1169
1170         /* Get all of the parent groups that contain this qgroup */
1171         list_for_each_entry(glist, &qgroup->groups, next_group) {
1172                 ret = ulist_add(tmp, glist->group->qgroupid,
1173                                 qgroup_to_aux(glist->group), GFP_ATOMIC);
1174                 if (ret < 0)
1175                         goto out;
1176         }
1177
1178         /* Iterate all of the parents and adjust their reference counts */
1179         ULIST_ITER_INIT(&uiter);
1180         while ((unode = ulist_next(tmp, &uiter))) {
1181                 qgroup = unode_aux_to_qgroup(unode);
1182                 qgroup->rfer += sign * num_bytes;
1183                 qgroup->rfer_cmpr += sign * num_bytes;
1184                 WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1185                 qgroup->excl += sign * num_bytes;
1186                 if (sign > 0)
1187                         qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1188                 else
1189                         qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1190                 qgroup->excl_cmpr += sign * num_bytes;
1191                 qgroup_dirty(fs_info, qgroup);
1192
1193                 /* Add any parents of the parents */
1194                 list_for_each_entry(glist, &qgroup->groups, next_group) {
1195                         ret = ulist_add(tmp, glist->group->qgroupid,
1196                                         qgroup_to_aux(glist->group), GFP_ATOMIC);
1197                         if (ret < 0)
1198                                 goto out;
1199                 }
1200         }
1201         ret = 0;
1202 out:
1203         return ret;
1204 }
1205
1206
1207 /*
1208  * Quick path for updating qgroup with only excl refs.
1209  *
1210  * In that case, just update all parent will be enough.
1211  * Or we needs to do a full rescan.
1212  * Caller should also hold fs_info->qgroup_lock.
1213  *
1214  * Return 0 for quick update, return >0 for need to full rescan
1215  * and mark INCONSISTENT flag.
1216  * Return < 0 for other error.
1217  */
1218 static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1219                                    struct ulist *tmp, u64 src, u64 dst,
1220                                    int sign)
1221 {
1222         struct btrfs_qgroup *qgroup;
1223         int ret = 1;
1224         int err = 0;
1225
1226         qgroup = find_qgroup_rb(fs_info, src);
1227         if (!qgroup)
1228                 goto out;
1229         if (qgroup->excl == qgroup->rfer) {
1230                 ret = 0;
1231                 err = __qgroup_excl_accounting(fs_info, tmp, dst,
1232                                                qgroup, sign);
1233                 if (err < 0) {
1234                         ret = err;
1235                         goto out;
1236                 }
1237         }
1238 out:
1239         if (ret)
1240                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1241         return ret;
1242 }
1243
1244 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1245                               u64 dst)
1246 {
1247         struct btrfs_fs_info *fs_info = trans->fs_info;
1248         struct btrfs_root *quota_root;
1249         struct btrfs_qgroup *parent;
1250         struct btrfs_qgroup *member;
1251         struct btrfs_qgroup_list *list;
1252         struct ulist *tmp;
1253         int ret = 0;
1254
1255         /* Check the level of src and dst first */
1256         if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1257                 return -EINVAL;
1258
1259         tmp = ulist_alloc(GFP_KERNEL);
1260         if (!tmp)
1261                 return -ENOMEM;
1262
1263         mutex_lock(&fs_info->qgroup_ioctl_lock);
1264         quota_root = fs_info->quota_root;
1265         if (!quota_root) {
1266                 ret = -EINVAL;
1267                 goto out;
1268         }
1269         member = find_qgroup_rb(fs_info, src);
1270         parent = find_qgroup_rb(fs_info, dst);
1271         if (!member || !parent) {
1272                 ret = -EINVAL;
1273                 goto out;
1274         }
1275
1276         /* check if such qgroup relation exist firstly */
1277         list_for_each_entry(list, &member->groups, next_group) {
1278                 if (list->group == parent) {
1279                         ret = -EEXIST;
1280                         goto out;
1281                 }
1282         }
1283
1284         ret = add_qgroup_relation_item(trans, src, dst);
1285         if (ret)
1286                 goto out;
1287
1288         ret = add_qgroup_relation_item(trans, dst, src);
1289         if (ret) {
1290                 del_qgroup_relation_item(trans, src, dst);
1291                 goto out;
1292         }
1293
1294         spin_lock(&fs_info->qgroup_lock);
1295         ret = add_relation_rb(fs_info, src, dst);
1296         if (ret < 0) {
1297                 spin_unlock(&fs_info->qgroup_lock);
1298                 goto out;
1299         }
1300         ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1301         spin_unlock(&fs_info->qgroup_lock);
1302 out:
1303         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1304         ulist_free(tmp);
1305         return ret;
1306 }
1307
1308 static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1309                                  u64 dst)
1310 {
1311         struct btrfs_fs_info *fs_info = trans->fs_info;
1312         struct btrfs_root *quota_root;
1313         struct btrfs_qgroup *parent;
1314         struct btrfs_qgroup *member;
1315         struct btrfs_qgroup_list *list;
1316         struct ulist *tmp;
1317         int ret = 0;
1318         int err;
1319
1320         tmp = ulist_alloc(GFP_KERNEL);
1321         if (!tmp)
1322                 return -ENOMEM;
1323
1324         quota_root = fs_info->quota_root;
1325         if (!quota_root) {
1326                 ret = -EINVAL;
1327                 goto out;
1328         }
1329
1330         member = find_qgroup_rb(fs_info, src);
1331         parent = find_qgroup_rb(fs_info, dst);
1332         if (!member || !parent) {
1333                 ret = -EINVAL;
1334                 goto out;
1335         }
1336
1337         /* check if such qgroup relation exist firstly */
1338         list_for_each_entry(list, &member->groups, next_group) {
1339                 if (list->group == parent)
1340                         goto exist;
1341         }
1342         ret = -ENOENT;
1343         goto out;
1344 exist:
1345         ret = del_qgroup_relation_item(trans, src, dst);
1346         err = del_qgroup_relation_item(trans, dst, src);
1347         if (err && !ret)
1348                 ret = err;
1349
1350         spin_lock(&fs_info->qgroup_lock);
1351         del_relation_rb(fs_info, src, dst);
1352         ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1353         spin_unlock(&fs_info->qgroup_lock);
1354 out:
1355         ulist_free(tmp);
1356         return ret;
1357 }
1358
1359 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1360                               u64 dst)
1361 {
1362         struct btrfs_fs_info *fs_info = trans->fs_info;
1363         int ret = 0;
1364
1365         mutex_lock(&fs_info->qgroup_ioctl_lock);
1366         ret = __del_qgroup_relation(trans, src, dst);
1367         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1368
1369         return ret;
1370 }
1371
1372 int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1373 {
1374         struct btrfs_fs_info *fs_info = trans->fs_info;
1375         struct btrfs_root *quota_root;
1376         struct btrfs_qgroup *qgroup;
1377         int ret = 0;
1378
1379         mutex_lock(&fs_info->qgroup_ioctl_lock);
1380         quota_root = fs_info->quota_root;
1381         if (!quota_root) {
1382                 ret = -EINVAL;
1383                 goto out;
1384         }
1385         qgroup = find_qgroup_rb(fs_info, qgroupid);
1386         if (qgroup) {
1387                 ret = -EEXIST;
1388                 goto out;
1389         }
1390
1391         ret = add_qgroup_item(trans, quota_root, qgroupid);
1392         if (ret)
1393                 goto out;
1394
1395         spin_lock(&fs_info->qgroup_lock);
1396         qgroup = add_qgroup_rb(fs_info, qgroupid);
1397         spin_unlock(&fs_info->qgroup_lock);
1398
1399         if (IS_ERR(qgroup))
1400                 ret = PTR_ERR(qgroup);
1401 out:
1402         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1403         return ret;
1404 }
1405
1406 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1407 {
1408         struct btrfs_fs_info *fs_info = trans->fs_info;
1409         struct btrfs_root *quota_root;
1410         struct btrfs_qgroup *qgroup;
1411         struct btrfs_qgroup_list *list;
1412         int ret = 0;
1413
1414         mutex_lock(&fs_info->qgroup_ioctl_lock);
1415         quota_root = fs_info->quota_root;
1416         if (!quota_root) {
1417                 ret = -EINVAL;
1418                 goto out;
1419         }
1420
1421         qgroup = find_qgroup_rb(fs_info, qgroupid);
1422         if (!qgroup) {
1423                 ret = -ENOENT;
1424                 goto out;
1425         }
1426
1427         /* Check if there are no children of this qgroup */
1428         if (!list_empty(&qgroup->members)) {
1429                 ret = -EBUSY;
1430                 goto out;
1431         }
1432
1433         ret = del_qgroup_item(trans, qgroupid);
1434         if (ret && ret != -ENOENT)
1435                 goto out;
1436
1437         while (!list_empty(&qgroup->groups)) {
1438                 list = list_first_entry(&qgroup->groups,
1439                                         struct btrfs_qgroup_list, next_group);
1440                 ret = __del_qgroup_relation(trans, qgroupid,
1441                                             list->group->qgroupid);
1442                 if (ret)
1443                         goto out;
1444         }
1445
1446         spin_lock(&fs_info->qgroup_lock);
1447         del_qgroup_rb(fs_info, qgroupid);
1448         spin_unlock(&fs_info->qgroup_lock);
1449 out:
1450         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1451         return ret;
1452 }
1453
1454 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
1455                        struct btrfs_qgroup_limit *limit)
1456 {
1457         struct btrfs_fs_info *fs_info = trans->fs_info;
1458         struct btrfs_root *quota_root;
1459         struct btrfs_qgroup *qgroup;
1460         int ret = 0;
1461         /* Sometimes we would want to clear the limit on this qgroup.
1462          * To meet this requirement, we treat the -1 as a special value
1463          * which tell kernel to clear the limit on this qgroup.
1464          */
1465         const u64 CLEAR_VALUE = -1;
1466
1467         mutex_lock(&fs_info->qgroup_ioctl_lock);
1468         quota_root = fs_info->quota_root;
1469         if (!quota_root) {
1470                 ret = -EINVAL;
1471                 goto out;
1472         }
1473
1474         qgroup = find_qgroup_rb(fs_info, qgroupid);
1475         if (!qgroup) {
1476                 ret = -ENOENT;
1477                 goto out;
1478         }
1479
1480         spin_lock(&fs_info->qgroup_lock);
1481         if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1482                 if (limit->max_rfer == CLEAR_VALUE) {
1483                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1484                         limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1485                         qgroup->max_rfer = 0;
1486                 } else {
1487                         qgroup->max_rfer = limit->max_rfer;
1488                 }
1489         }
1490         if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1491                 if (limit->max_excl == CLEAR_VALUE) {
1492                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1493                         limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1494                         qgroup->max_excl = 0;
1495                 } else {
1496                         qgroup->max_excl = limit->max_excl;
1497                 }
1498         }
1499         if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1500                 if (limit->rsv_rfer == CLEAR_VALUE) {
1501                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1502                         limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1503                         qgroup->rsv_rfer = 0;
1504                 } else {
1505                         qgroup->rsv_rfer = limit->rsv_rfer;
1506                 }
1507         }
1508         if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1509                 if (limit->rsv_excl == CLEAR_VALUE) {
1510                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1511                         limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1512                         qgroup->rsv_excl = 0;
1513                 } else {
1514                         qgroup->rsv_excl = limit->rsv_excl;
1515                 }
1516         }
1517         qgroup->lim_flags |= limit->flags;
1518
1519         spin_unlock(&fs_info->qgroup_lock);
1520
1521         ret = update_qgroup_limit_item(trans, qgroup);
1522         if (ret) {
1523                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1524                 btrfs_info(fs_info, "unable to update quota limit for %llu",
1525                        qgroupid);
1526         }
1527
1528 out:
1529         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1530         return ret;
1531 }
1532
1533 int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1534                                 struct btrfs_delayed_ref_root *delayed_refs,
1535                                 struct btrfs_qgroup_extent_record *record)
1536 {
1537         struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1538         struct rb_node *parent_node = NULL;
1539         struct btrfs_qgroup_extent_record *entry;
1540         u64 bytenr = record->bytenr;
1541
1542         lockdep_assert_held(&delayed_refs->lock);
1543         trace_btrfs_qgroup_trace_extent(fs_info, record);
1544
1545         while (*p) {
1546                 parent_node = *p;
1547                 entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1548                                  node);
1549                 if (bytenr < entry->bytenr)
1550                         p = &(*p)->rb_left;
1551                 else if (bytenr > entry->bytenr)
1552                         p = &(*p)->rb_right;
1553                 else
1554                         return 1;
1555         }
1556
1557         rb_link_node(&record->node, parent_node, p);
1558         rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1559         return 0;
1560 }
1561
1562 int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info,
1563                                    struct btrfs_qgroup_extent_record *qrecord)
1564 {
1565         struct ulist *old_root;
1566         u64 bytenr = qrecord->bytenr;
1567         int ret;
1568
1569         ret = btrfs_find_all_roots(NULL, fs_info, bytenr, 0, &old_root, false);
1570         if (ret < 0) {
1571                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1572                 btrfs_warn(fs_info,
1573 "error accounting new delayed refs extent (err code: %d), quota inconsistent",
1574                         ret);
1575                 return 0;
1576         }
1577
1578         /*
1579          * Here we don't need to get the lock of
1580          * trans->transaction->delayed_refs, since inserted qrecord won't
1581          * be deleted, only qrecord->node may be modified (new qrecord insert)
1582          *
1583          * So modifying qrecord->old_roots is safe here
1584          */
1585         qrecord->old_roots = old_root;
1586         return 0;
1587 }
1588
1589 int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
1590                               u64 num_bytes, gfp_t gfp_flag)
1591 {
1592         struct btrfs_fs_info *fs_info = trans->fs_info;
1593         struct btrfs_qgroup_extent_record *record;
1594         struct btrfs_delayed_ref_root *delayed_refs;
1595         int ret;
1596
1597         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)
1598             || bytenr == 0 || num_bytes == 0)
1599                 return 0;
1600         record = kmalloc(sizeof(*record), gfp_flag);
1601         if (!record)
1602                 return -ENOMEM;
1603
1604         delayed_refs = &trans->transaction->delayed_refs;
1605         record->bytenr = bytenr;
1606         record->num_bytes = num_bytes;
1607         record->old_roots = NULL;
1608
1609         spin_lock(&delayed_refs->lock);
1610         ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
1611         spin_unlock(&delayed_refs->lock);
1612         if (ret > 0) {
1613                 kfree(record);
1614                 return 0;
1615         }
1616         return btrfs_qgroup_trace_extent_post(fs_info, record);
1617 }
1618
1619 int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
1620                                   struct extent_buffer *eb)
1621 {
1622         struct btrfs_fs_info *fs_info = trans->fs_info;
1623         int nr = btrfs_header_nritems(eb);
1624         int i, extent_type, ret;
1625         struct btrfs_key key;
1626         struct btrfs_file_extent_item *fi;
1627         u64 bytenr, num_bytes;
1628
1629         /* We can be called directly from walk_up_proc() */
1630         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1631                 return 0;
1632
1633         for (i = 0; i < nr; i++) {
1634                 btrfs_item_key_to_cpu(eb, &key, i);
1635
1636                 if (key.type != BTRFS_EXTENT_DATA_KEY)
1637                         continue;
1638
1639                 fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
1640                 /* filter out non qgroup-accountable extents  */
1641                 extent_type = btrfs_file_extent_type(eb, fi);
1642
1643                 if (extent_type == BTRFS_FILE_EXTENT_INLINE)
1644                         continue;
1645
1646                 bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
1647                 if (!bytenr)
1648                         continue;
1649
1650                 num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
1651
1652                 ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes,
1653                                                 GFP_NOFS);
1654                 if (ret)
1655                         return ret;
1656         }
1657         cond_resched();
1658         return 0;
1659 }
1660
1661 /*
1662  * Walk up the tree from the bottom, freeing leaves and any interior
1663  * nodes which have had all slots visited. If a node (leaf or
1664  * interior) is freed, the node above it will have it's slot
1665  * incremented. The root node will never be freed.
1666  *
1667  * At the end of this function, we should have a path which has all
1668  * slots incremented to the next position for a search. If we need to
1669  * read a new node it will be NULL and the node above it will have the
1670  * correct slot selected for a later read.
1671  *
1672  * If we increment the root nodes slot counter past the number of
1673  * elements, 1 is returned to signal completion of the search.
1674  */
1675 static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
1676 {
1677         int level = 0;
1678         int nr, slot;
1679         struct extent_buffer *eb;
1680
1681         if (root_level == 0)
1682                 return 1;
1683
1684         while (level <= root_level) {
1685                 eb = path->nodes[level];
1686                 nr = btrfs_header_nritems(eb);
1687                 path->slots[level]++;
1688                 slot = path->slots[level];
1689                 if (slot >= nr || level == 0) {
1690                         /*
1691                          * Don't free the root -  we will detect this
1692                          * condition after our loop and return a
1693                          * positive value for caller to stop walking the tree.
1694                          */
1695                         if (level != root_level) {
1696                                 btrfs_tree_unlock_rw(eb, path->locks[level]);
1697                                 path->locks[level] = 0;
1698
1699                                 free_extent_buffer(eb);
1700                                 path->nodes[level] = NULL;
1701                                 path->slots[level] = 0;
1702                         }
1703                 } else {
1704                         /*
1705                          * We have a valid slot to walk back down
1706                          * from. Stop here so caller can process these
1707                          * new nodes.
1708                          */
1709                         break;
1710                 }
1711
1712                 level++;
1713         }
1714
1715         eb = path->nodes[root_level];
1716         if (path->slots[root_level] >= btrfs_header_nritems(eb))
1717                 return 1;
1718
1719         return 0;
1720 }
1721
1722 /*
1723  * Helper function to trace a subtree tree block swap.
1724  *
1725  * The swap will happen in highest tree block, but there may be a lot of
1726  * tree blocks involved.
1727  *
1728  * For example:
1729  *  OO = Old tree blocks
1730  *  NN = New tree blocks allocated during balance
1731  *
1732  *           File tree (257)                  Reloc tree for 257
1733  * L2              OO                                NN
1734  *               /    \                            /    \
1735  * L1          OO      OO (a)                    OO      NN (a)
1736  *            / \     / \                       / \     / \
1737  * L0       OO   OO OO   OO                   OO   OO NN   NN
1738  *                  (b)  (c)                          (b)  (c)
1739  *
1740  * When calling qgroup_trace_extent_swap(), we will pass:
1741  * @src_eb = OO(a)
1742  * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
1743  * @dst_level = 0
1744  * @root_level = 1
1745  *
1746  * In that case, qgroup_trace_extent_swap() will search from OO(a) to
1747  * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
1748  *
1749  * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
1750  *
1751  * 1) Tree search from @src_eb
1752  *    It should acts as a simplified btrfs_search_slot().
1753  *    The key for search can be extracted from @dst_path->nodes[dst_level]
1754  *    (first key).
1755  *
1756  * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
1757  *    NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
1758  *    They should be marked during previous (@dst_level = 1) iteration.
1759  *
1760  * 3) Mark file extents in leaves dirty
1761  *    We don't have good way to pick out new file extents only.
1762  *    So we still follow the old method by scanning all file extents in
1763  *    the leave.
1764  *
1765  * This function can free us from keeping two paths, thus later we only need
1766  * to care about how to iterate all new tree blocks in reloc tree.
1767  */
1768 static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
1769                                     struct extent_buffer *src_eb,
1770                                     struct btrfs_path *dst_path,
1771                                     int dst_level, int root_level,
1772                                     bool trace_leaf)
1773 {
1774         struct btrfs_key key;
1775         struct btrfs_path *src_path;
1776         struct btrfs_fs_info *fs_info = trans->fs_info;
1777         u32 nodesize = fs_info->nodesize;
1778         int cur_level = root_level;
1779         int ret;
1780
1781         BUG_ON(dst_level > root_level);
1782         /* Level mismatch */
1783         if (btrfs_header_level(src_eb) != root_level)
1784                 return -EINVAL;
1785
1786         src_path = btrfs_alloc_path();
1787         if (!src_path) {
1788                 ret = -ENOMEM;
1789                 goto out;
1790         }
1791
1792         if (dst_level)
1793                 btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
1794         else
1795                 btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
1796
1797         /* For src_path */
1798         extent_buffer_get(src_eb);
1799         src_path->nodes[root_level] = src_eb;
1800         src_path->slots[root_level] = dst_path->slots[root_level];
1801         src_path->locks[root_level] = 0;
1802
1803         /* A simplified version of btrfs_search_slot() */
1804         while (cur_level >= dst_level) {
1805                 struct btrfs_key src_key;
1806                 struct btrfs_key dst_key;
1807
1808                 if (src_path->nodes[cur_level] == NULL) {
1809                         struct btrfs_key first_key;
1810                         struct extent_buffer *eb;
1811                         int parent_slot;
1812                         u64 child_gen;
1813                         u64 child_bytenr;
1814
1815                         eb = src_path->nodes[cur_level + 1];
1816                         parent_slot = src_path->slots[cur_level + 1];
1817                         child_bytenr = btrfs_node_blockptr(eb, parent_slot);
1818                         child_gen = btrfs_node_ptr_generation(eb, parent_slot);
1819                         btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
1820
1821                         eb = read_tree_block(fs_info, child_bytenr, child_gen,
1822                                              cur_level, &first_key);
1823                         if (IS_ERR(eb)) {
1824                                 ret = PTR_ERR(eb);
1825                                 goto out;
1826                         } else if (!extent_buffer_uptodate(eb)) {
1827                                 free_extent_buffer(eb);
1828                                 ret = -EIO;
1829                                 goto out;
1830                         }
1831
1832                         src_path->nodes[cur_level] = eb;
1833
1834                         btrfs_tree_read_lock(eb);
1835                         btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
1836                         src_path->locks[cur_level] = BTRFS_READ_LOCK_BLOCKING;
1837                 }
1838
1839                 src_path->slots[cur_level] = dst_path->slots[cur_level];
1840                 if (cur_level) {
1841                         btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
1842                                         &dst_key, dst_path->slots[cur_level]);
1843                         btrfs_node_key_to_cpu(src_path->nodes[cur_level],
1844                                         &src_key, src_path->slots[cur_level]);
1845                 } else {
1846                         btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
1847                                         &dst_key, dst_path->slots[cur_level]);
1848                         btrfs_item_key_to_cpu(src_path->nodes[cur_level],
1849                                         &src_key, src_path->slots[cur_level]);
1850                 }
1851                 /* Content mismatch, something went wrong */
1852                 if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
1853                         ret = -ENOENT;
1854                         goto out;
1855                 }
1856                 cur_level--;
1857         }
1858
1859         /*
1860          * Now both @dst_path and @src_path have been populated, record the tree
1861          * blocks for qgroup accounting.
1862          */
1863         ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
1864                         nodesize, GFP_NOFS);
1865         if (ret < 0)
1866                 goto out;
1867         ret = btrfs_qgroup_trace_extent(trans,
1868                         dst_path->nodes[dst_level]->start,
1869                         nodesize, GFP_NOFS);
1870         if (ret < 0)
1871                 goto out;
1872
1873         /* Record leaf file extents */
1874         if (dst_level == 0 && trace_leaf) {
1875                 ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
1876                 if (ret < 0)
1877                         goto out;
1878                 ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
1879         }
1880 out:
1881         btrfs_free_path(src_path);
1882         return ret;
1883 }
1884
1885 /*
1886  * Helper function to do recursive generation-aware depth-first search, to
1887  * locate all new tree blocks in a subtree of reloc tree.
1888  *
1889  * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
1890  *         reloc tree
1891  * L2         NN (a)
1892  *          /    \
1893  * L1    OO        NN (b)
1894  *      /  \      /  \
1895  * L0  OO  OO    OO  NN
1896  *               (c) (d)
1897  * If we pass:
1898  * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
1899  * @cur_level = 1
1900  * @root_level = 1
1901  *
1902  * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
1903  * above tree blocks along with their counter parts in file tree.
1904  * While during search, old tree blocks OO(c) will be skipped as tree block swap
1905  * won't affect OO(c).
1906  */
1907 static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
1908                                            struct extent_buffer *src_eb,
1909                                            struct btrfs_path *dst_path,
1910                                            int cur_level, int root_level,
1911                                            u64 last_snapshot, bool trace_leaf)
1912 {
1913         struct btrfs_fs_info *fs_info = trans->fs_info;
1914         struct extent_buffer *eb;
1915         bool need_cleanup = false;
1916         int ret = 0;
1917         int i;
1918
1919         /* Level sanity check */
1920         if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL ||
1921             root_level < 0 || root_level >= BTRFS_MAX_LEVEL ||
1922             root_level < cur_level) {
1923                 btrfs_err_rl(fs_info,
1924                         "%s: bad levels, cur_level=%d root_level=%d",
1925                         __func__, cur_level, root_level);
1926                 return -EUCLEAN;
1927         }
1928
1929         /* Read the tree block if needed */
1930         if (dst_path->nodes[cur_level] == NULL) {
1931                 struct btrfs_key first_key;
1932                 int parent_slot;
1933                 u64 child_gen;
1934                 u64 child_bytenr;
1935
1936                 /*
1937                  * dst_path->nodes[root_level] must be initialized before
1938                  * calling this function.
1939                  */
1940                 if (cur_level == root_level) {
1941                         btrfs_err_rl(fs_info,
1942         "%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
1943                                 __func__, root_level, root_level, cur_level);
1944                         return -EUCLEAN;
1945                 }
1946
1947                 /*
1948                  * We need to get child blockptr/gen from parent before we can
1949                  * read it.
1950                   */
1951                 eb = dst_path->nodes[cur_level + 1];
1952                 parent_slot = dst_path->slots[cur_level + 1];
1953                 child_bytenr = btrfs_node_blockptr(eb, parent_slot);
1954                 child_gen = btrfs_node_ptr_generation(eb, parent_slot);
1955                 btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
1956
1957                 /* This node is old, no need to trace */
1958                 if (child_gen < last_snapshot)
1959                         goto out;
1960
1961                 eb = read_tree_block(fs_info, child_bytenr, child_gen,
1962                                      cur_level, &first_key);
1963                 if (IS_ERR(eb)) {
1964                         ret = PTR_ERR(eb);
1965                         goto out;
1966                 } else if (!extent_buffer_uptodate(eb)) {
1967                         free_extent_buffer(eb);
1968                         ret = -EIO;
1969                         goto out;
1970                 }
1971
1972                 dst_path->nodes[cur_level] = eb;
1973                 dst_path->slots[cur_level] = 0;
1974
1975                 btrfs_tree_read_lock(eb);
1976                 btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
1977                 dst_path->locks[cur_level] = BTRFS_READ_LOCK_BLOCKING;
1978                 need_cleanup = true;
1979         }
1980
1981         /* Now record this tree block and its counter part for qgroups */
1982         ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
1983                                        root_level, trace_leaf);
1984         if (ret < 0)
1985                 goto cleanup;
1986
1987         eb = dst_path->nodes[cur_level];
1988
1989         if (cur_level > 0) {
1990                 /* Iterate all child tree blocks */
1991                 for (i = 0; i < btrfs_header_nritems(eb); i++) {
1992                         /* Skip old tree blocks as they won't be swapped */
1993                         if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
1994                                 continue;
1995                         dst_path->slots[cur_level] = i;
1996
1997                         /* Recursive call (at most 7 times) */
1998                         ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
1999                                         dst_path, cur_level - 1, root_level,
2000                                         last_snapshot, trace_leaf);
2001                         if (ret < 0)
2002                                 goto cleanup;
2003                 }
2004         }
2005
2006 cleanup:
2007         if (need_cleanup) {
2008                 /* Clean up */
2009                 btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2010                                      dst_path->locks[cur_level]);
2011                 free_extent_buffer(dst_path->nodes[cur_level]);
2012                 dst_path->nodes[cur_level] = NULL;
2013                 dst_path->slots[cur_level] = 0;
2014                 dst_path->locks[cur_level] = 0;
2015         }
2016 out:
2017         return ret;
2018 }
2019
2020 /*
2021  * Inform qgroup to trace subtree swap used in balance.
2022  *
2023  * Unlike btrfs_qgroup_trace_subtree(), this function will only trace
2024  * new tree blocks whose generation is equal to (or larger than) @last_snapshot.
2025  *
2026  * Will go down the tree block pointed by @dst_eb (pointed by @dst_parent and
2027  * @dst_slot), and find any tree blocks whose generation is at @last_snapshot,
2028  * and then go down @src_eb (pointed by @src_parent and @src_slot) to find
2029  * the counterpart of the tree block, then mark both tree blocks as qgroup dirty,
2030  * and skip all tree blocks whose generation is smaller than last_snapshot.
2031  *
2032  * This would skip tons of tree blocks of original btrfs_qgroup_trace_subtree(),
2033  * which could be the cause of very slow balance if the file tree is large.
2034  *
2035  * @src_parent, @src_slot: pointer to src (file tree) eb.
2036  * @dst_parent, @dst_slot: pointer to dst (reloc tree) eb.
2037  */
2038 int btrfs_qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2039                                 struct btrfs_block_group_cache *bg_cache,
2040                                 struct extent_buffer *src_parent, int src_slot,
2041                                 struct extent_buffer *dst_parent, int dst_slot,
2042                                 u64 last_snapshot)
2043 {
2044         struct btrfs_fs_info *fs_info = trans->fs_info;
2045         struct btrfs_path *dst_path = NULL;
2046         struct btrfs_key first_key;
2047         struct extent_buffer *src_eb = NULL;
2048         struct extent_buffer *dst_eb = NULL;
2049         bool trace_leaf = false;
2050         u64 child_gen;
2051         u64 child_bytenr;
2052         int level;
2053         int ret;
2054
2055         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2056                 return 0;
2057
2058         /* Check parameter order */
2059         if (btrfs_node_ptr_generation(src_parent, src_slot) >
2060             btrfs_node_ptr_generation(dst_parent, dst_slot)) {
2061                 btrfs_err_rl(fs_info,
2062                 "%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2063                         btrfs_node_ptr_generation(src_parent, src_slot),
2064                         btrfs_node_ptr_generation(dst_parent, dst_slot));
2065                 return -EUCLEAN;
2066         }
2067
2068         /*
2069          * Only trace leaf if we're relocating data block groups, this could
2070          * reduce tons of data extents tracing for meta/sys bg relocation.
2071          */
2072         if (bg_cache->flags & BTRFS_BLOCK_GROUP_DATA)
2073                 trace_leaf = true;
2074         /* Read out real @src_eb, pointed by @src_parent and @src_slot */
2075         child_bytenr = btrfs_node_blockptr(src_parent, src_slot);
2076         child_gen = btrfs_node_ptr_generation(src_parent, src_slot);
2077         btrfs_node_key_to_cpu(src_parent, &first_key, src_slot);
2078
2079         src_eb = read_tree_block(fs_info, child_bytenr, child_gen,
2080                         btrfs_header_level(src_parent) - 1, &first_key);
2081         if (IS_ERR(src_eb)) {
2082                 ret = PTR_ERR(src_eb);
2083                 goto out;
2084         }
2085
2086         /* Read out real @dst_eb, pointed by @src_parent and @src_slot */
2087         child_bytenr = btrfs_node_blockptr(dst_parent, dst_slot);
2088         child_gen = btrfs_node_ptr_generation(dst_parent, dst_slot);
2089         btrfs_node_key_to_cpu(dst_parent, &first_key, dst_slot);
2090
2091         dst_eb = read_tree_block(fs_info, child_bytenr, child_gen,
2092                         btrfs_header_level(dst_parent) - 1, &first_key);
2093         if (IS_ERR(dst_eb)) {
2094                 ret = PTR_ERR(dst_eb);
2095                 goto out;
2096         }
2097
2098         if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2099                 ret = -EINVAL;
2100                 goto out;
2101         }
2102
2103         level = btrfs_header_level(dst_eb);
2104         dst_path = btrfs_alloc_path();
2105         if (!dst_path) {
2106                 ret = -ENOMEM;
2107                 goto out;
2108         }
2109
2110         /* For dst_path */
2111         extent_buffer_get(dst_eb);
2112         dst_path->nodes[level] = dst_eb;
2113         dst_path->slots[level] = 0;
2114         dst_path->locks[level] = 0;
2115
2116         /* Do the generation-aware breadth-first search */
2117         ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2118                                               level, last_snapshot, trace_leaf);
2119         if (ret < 0)
2120                 goto out;
2121         ret = 0;
2122
2123 out:
2124         free_extent_buffer(src_eb);
2125         free_extent_buffer(dst_eb);
2126         btrfs_free_path(dst_path);
2127         if (ret < 0)
2128                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2129         return ret;
2130 }
2131
2132 int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
2133                                struct extent_buffer *root_eb,
2134                                u64 root_gen, int root_level)
2135 {
2136         struct btrfs_fs_info *fs_info = trans->fs_info;
2137         int ret = 0;
2138         int level;
2139         struct extent_buffer *eb = root_eb;
2140         struct btrfs_path *path = NULL;
2141
2142         BUG_ON(root_level < 0 || root_level >= BTRFS_MAX_LEVEL);
2143         BUG_ON(root_eb == NULL);
2144
2145         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2146                 return 0;
2147
2148         if (!extent_buffer_uptodate(root_eb)) {
2149                 ret = btrfs_read_buffer(root_eb, root_gen, root_level, NULL);
2150                 if (ret)
2151                         goto out;
2152         }
2153
2154         if (root_level == 0) {
2155                 ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2156                 goto out;
2157         }
2158
2159         path = btrfs_alloc_path();
2160         if (!path)
2161                 return -ENOMEM;
2162
2163         /*
2164          * Walk down the tree.  Missing extent blocks are filled in as
2165          * we go. Metadata is accounted every time we read a new
2166          * extent block.
2167          *
2168          * When we reach a leaf, we account for file extent items in it,
2169          * walk back up the tree (adjusting slot pointers as we go)
2170          * and restart the search process.
2171          */
2172         extent_buffer_get(root_eb); /* For path */
2173         path->nodes[root_level] = root_eb;
2174         path->slots[root_level] = 0;
2175         path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2176 walk_down:
2177         level = root_level;
2178         while (level >= 0) {
2179                 if (path->nodes[level] == NULL) {
2180                         struct btrfs_key first_key;
2181                         int parent_slot;
2182                         u64 child_gen;
2183                         u64 child_bytenr;
2184
2185                         /*
2186                          * We need to get child blockptr/gen from parent before
2187                          * we can read it.
2188                           */
2189                         eb = path->nodes[level + 1];
2190                         parent_slot = path->slots[level + 1];
2191                         child_bytenr = btrfs_node_blockptr(eb, parent_slot);
2192                         child_gen = btrfs_node_ptr_generation(eb, parent_slot);
2193                         btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
2194
2195                         eb = read_tree_block(fs_info, child_bytenr, child_gen,
2196                                              level, &first_key);
2197                         if (IS_ERR(eb)) {
2198                                 ret = PTR_ERR(eb);
2199                                 goto out;
2200                         } else if (!extent_buffer_uptodate(eb)) {
2201                                 free_extent_buffer(eb);
2202                                 ret = -EIO;
2203                                 goto out;
2204                         }
2205
2206                         path->nodes[level] = eb;
2207                         path->slots[level] = 0;
2208
2209                         btrfs_tree_read_lock(eb);
2210                         btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
2211                         path->locks[level] = BTRFS_READ_LOCK_BLOCKING;
2212
2213                         ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2214                                                         fs_info->nodesize,
2215                                                         GFP_NOFS);
2216                         if (ret)
2217                                 goto out;
2218                 }
2219
2220                 if (level == 0) {
2221                         ret = btrfs_qgroup_trace_leaf_items(trans,
2222                                                             path->nodes[level]);
2223                         if (ret)
2224                                 goto out;
2225
2226                         /* Nonzero return here means we completed our search */
2227                         ret = adjust_slots_upwards(path, root_level);
2228                         if (ret)
2229                                 break;
2230
2231                         /* Restart search with new slots */
2232                         goto walk_down;
2233                 }
2234
2235                 level--;
2236         }
2237
2238         ret = 0;
2239 out:
2240         btrfs_free_path(path);
2241
2242         return ret;
2243 }
2244
2245 #define UPDATE_NEW      0
2246 #define UPDATE_OLD      1
2247 /*
2248  * Walk all of the roots that points to the bytenr and adjust their refcnts.
2249  */
2250 static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2251                                 struct ulist *roots, struct ulist *tmp,
2252                                 struct ulist *qgroups, u64 seq, int update_old)
2253 {
2254         struct ulist_node *unode;
2255         struct ulist_iterator uiter;
2256         struct ulist_node *tmp_unode;
2257         struct ulist_iterator tmp_uiter;
2258         struct btrfs_qgroup *qg;
2259         int ret = 0;
2260
2261         if (!roots)
2262                 return 0;
2263         ULIST_ITER_INIT(&uiter);
2264         while ((unode = ulist_next(roots, &uiter))) {
2265                 qg = find_qgroup_rb(fs_info, unode->val);
2266                 if (!qg)
2267                         continue;
2268
2269                 ulist_reinit(tmp);
2270                 ret = ulist_add(qgroups, qg->qgroupid, qgroup_to_aux(qg),
2271                                 GFP_ATOMIC);
2272                 if (ret < 0)
2273                         return ret;
2274                 ret = ulist_add(tmp, qg->qgroupid, qgroup_to_aux(qg), GFP_ATOMIC);
2275                 if (ret < 0)
2276                         return ret;
2277                 ULIST_ITER_INIT(&tmp_uiter);
2278                 while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
2279                         struct btrfs_qgroup_list *glist;
2280
2281                         qg = unode_aux_to_qgroup(tmp_unode);
2282                         if (update_old)
2283                                 btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2284                         else
2285                                 btrfs_qgroup_update_new_refcnt(qg, seq, 1);
2286                         list_for_each_entry(glist, &qg->groups, next_group) {
2287                                 ret = ulist_add(qgroups, glist->group->qgroupid,
2288                                                 qgroup_to_aux(glist->group),
2289                                                 GFP_ATOMIC);
2290                                 if (ret < 0)
2291                                         return ret;
2292                                 ret = ulist_add(tmp, glist->group->qgroupid,
2293                                                 qgroup_to_aux(glist->group),
2294                                                 GFP_ATOMIC);
2295                                 if (ret < 0)
2296                                         return ret;
2297                         }
2298                 }
2299         }
2300         return 0;
2301 }
2302
2303 /*
2304  * Update qgroup rfer/excl counters.
2305  * Rfer update is easy, codes can explain themselves.
2306  *
2307  * Excl update is tricky, the update is split into 2 part.
2308  * Part 1: Possible exclusive <-> sharing detect:
2309  *      |       A       |       !A      |
2310  *  -------------------------------------
2311  *  B   |       *       |       -       |
2312  *  -------------------------------------
2313  *  !B  |       +       |       **      |
2314  *  -------------------------------------
2315  *
2316  * Conditions:
2317  * A:   cur_old_roots < nr_old_roots    (not exclusive before)
2318  * !A:  cur_old_roots == nr_old_roots   (possible exclusive before)
2319  * B:   cur_new_roots < nr_new_roots    (not exclusive now)
2320  * !B:  cur_new_roots == nr_new_roots   (possible exclusive now)
2321  *
2322  * Results:
2323  * +: Possible sharing -> exclusive     -: Possible exclusive -> sharing
2324  * *: Definitely not changed.           **: Possible unchanged.
2325  *
2326  * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2327  *
2328  * To make the logic clear, we first use condition A and B to split
2329  * combination into 4 results.
2330  *
2331  * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2332  * only on variant maybe 0.
2333  *
2334  * Lastly, check result **, since there are 2 variants maybe 0, split them
2335  * again(2x2).
2336  * But this time we don't need to consider other things, the codes and logic
2337  * is easy to understand now.
2338  */
2339 static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
2340                                   struct ulist *qgroups,
2341                                   u64 nr_old_roots,
2342                                   u64 nr_new_roots,
2343                                   u64 num_bytes, u64 seq)
2344 {
2345         struct ulist_node *unode;
2346         struct ulist_iterator uiter;
2347         struct btrfs_qgroup *qg;
2348         u64 cur_new_count, cur_old_count;
2349
2350         ULIST_ITER_INIT(&uiter);
2351         while ((unode = ulist_next(qgroups, &uiter))) {
2352                 bool dirty = false;
2353
2354                 qg = unode_aux_to_qgroup(unode);
2355                 cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2356                 cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2357
2358                 trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2359                                              cur_new_count);
2360
2361                 /* Rfer update part */
2362                 if (cur_old_count == 0 && cur_new_count > 0) {
2363                         qg->rfer += num_bytes;
2364                         qg->rfer_cmpr += num_bytes;
2365                         dirty = true;
2366                 }
2367                 if (cur_old_count > 0 && cur_new_count == 0) {
2368                         qg->rfer -= num_bytes;
2369                         qg->rfer_cmpr -= num_bytes;
2370                         dirty = true;
2371                 }
2372
2373                 /* Excl update part */
2374                 /* Exclusive/none -> shared case */
2375                 if (cur_old_count == nr_old_roots &&
2376                     cur_new_count < nr_new_roots) {
2377                         /* Exclusive -> shared */
2378                         if (cur_old_count != 0) {
2379                                 qg->excl -= num_bytes;
2380                                 qg->excl_cmpr -= num_bytes;
2381                                 dirty = true;
2382                         }
2383                 }
2384
2385                 /* Shared -> exclusive/none case */
2386                 if (cur_old_count < nr_old_roots &&
2387                     cur_new_count == nr_new_roots) {
2388                         /* Shared->exclusive */
2389                         if (cur_new_count != 0) {
2390                                 qg->excl += num_bytes;
2391                                 qg->excl_cmpr += num_bytes;
2392                                 dirty = true;
2393                         }
2394                 }
2395
2396                 /* Exclusive/none -> exclusive/none case */
2397                 if (cur_old_count == nr_old_roots &&
2398                     cur_new_count == nr_new_roots) {
2399                         if (cur_old_count == 0) {
2400                                 /* None -> exclusive/none */
2401
2402                                 if (cur_new_count != 0) {
2403                                         /* None -> exclusive */
2404                                         qg->excl += num_bytes;
2405                                         qg->excl_cmpr += num_bytes;
2406                                         dirty = true;
2407                                 }
2408                                 /* None -> none, nothing changed */
2409                         } else {
2410                                 /* Exclusive -> exclusive/none */
2411
2412                                 if (cur_new_count == 0) {
2413                                         /* Exclusive -> none */
2414                                         qg->excl -= num_bytes;
2415                                         qg->excl_cmpr -= num_bytes;
2416                                         dirty = true;
2417                                 }
2418                                 /* Exclusive -> exclusive, nothing changed */
2419                         }
2420                 }
2421
2422                 if (dirty)
2423                         qgroup_dirty(fs_info, qg);
2424         }
2425         return 0;
2426 }
2427
2428 /*
2429  * Check if the @roots potentially is a list of fs tree roots
2430  *
2431  * Return 0 for definitely not a fs/subvol tree roots ulist
2432  * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2433  *          one as well)
2434  */
2435 static int maybe_fs_roots(struct ulist *roots)
2436 {
2437         struct ulist_node *unode;
2438         struct ulist_iterator uiter;
2439
2440         /* Empty one, still possible for fs roots */
2441         if (!roots || roots->nnodes == 0)
2442                 return 1;
2443
2444         ULIST_ITER_INIT(&uiter);
2445         unode = ulist_next(roots, &uiter);
2446         if (!unode)
2447                 return 1;
2448
2449         /*
2450          * If it contains fs tree roots, then it must belong to fs/subvol
2451          * trees.
2452          * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2453          */
2454         return is_fstree(unode->val);
2455 }
2456
2457 int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2458                                 u64 num_bytes, struct ulist *old_roots,
2459                                 struct ulist *new_roots)
2460 {
2461         struct btrfs_fs_info *fs_info = trans->fs_info;
2462         struct ulist *qgroups = NULL;
2463         struct ulist *tmp = NULL;
2464         u64 seq;
2465         u64 nr_new_roots = 0;
2466         u64 nr_old_roots = 0;
2467         int ret = 0;
2468
2469         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2470                 return 0;
2471
2472         if (new_roots) {
2473                 if (!maybe_fs_roots(new_roots))
2474                         goto out_free;
2475                 nr_new_roots = new_roots->nnodes;
2476         }
2477         if (old_roots) {
2478                 if (!maybe_fs_roots(old_roots))
2479                         goto out_free;
2480                 nr_old_roots = old_roots->nnodes;
2481         }
2482
2483         /* Quick exit, either not fs tree roots, or won't affect any qgroup */
2484         if (nr_old_roots == 0 && nr_new_roots == 0)
2485                 goto out_free;
2486
2487         BUG_ON(!fs_info->quota_root);
2488
2489         trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2490                                         num_bytes, nr_old_roots, nr_new_roots);
2491
2492         qgroups = ulist_alloc(GFP_NOFS);
2493         if (!qgroups) {
2494                 ret = -ENOMEM;
2495                 goto out_free;
2496         }
2497         tmp = ulist_alloc(GFP_NOFS);
2498         if (!tmp) {
2499                 ret = -ENOMEM;
2500                 goto out_free;
2501         }
2502
2503         mutex_lock(&fs_info->qgroup_rescan_lock);
2504         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2505                 if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2506                         mutex_unlock(&fs_info->qgroup_rescan_lock);
2507                         ret = 0;
2508                         goto out_free;
2509                 }
2510         }
2511         mutex_unlock(&fs_info->qgroup_rescan_lock);
2512
2513         spin_lock(&fs_info->qgroup_lock);
2514         seq = fs_info->qgroup_seq;
2515
2516         /* Update old refcnts using old_roots */
2517         ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
2518                                    UPDATE_OLD);
2519         if (ret < 0)
2520                 goto out;
2521
2522         /* Update new refcnts using new_roots */
2523         ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
2524                                    UPDATE_NEW);
2525         if (ret < 0)
2526                 goto out;
2527
2528         qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
2529                                num_bytes, seq);
2530
2531         /*
2532          * Bump qgroup_seq to avoid seq overlap
2533          */
2534         fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
2535 out:
2536         spin_unlock(&fs_info->qgroup_lock);
2537 out_free:
2538         ulist_free(tmp);
2539         ulist_free(qgroups);
2540         ulist_free(old_roots);
2541         ulist_free(new_roots);
2542         return ret;
2543 }
2544
2545 int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2546 {
2547         struct btrfs_fs_info *fs_info = trans->fs_info;
2548         struct btrfs_qgroup_extent_record *record;
2549         struct btrfs_delayed_ref_root *delayed_refs;
2550         struct ulist *new_roots = NULL;
2551         struct rb_node *node;
2552         u64 num_dirty_extents = 0;
2553         u64 qgroup_to_skip;
2554         int ret = 0;
2555
2556         delayed_refs = &trans->transaction->delayed_refs;
2557         qgroup_to_skip = delayed_refs->qgroup_to_skip;
2558         while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2559                 record = rb_entry(node, struct btrfs_qgroup_extent_record,
2560                                   node);
2561
2562                 num_dirty_extents++;
2563                 trace_btrfs_qgroup_account_extents(fs_info, record);
2564
2565                 if (!ret) {
2566                         /*
2567                          * Old roots should be searched when inserting qgroup
2568                          * extent record
2569                          */
2570                         if (WARN_ON(!record->old_roots)) {
2571                                 /* Search commit root to find old_roots */
2572                                 ret = btrfs_find_all_roots(NULL, fs_info,
2573                                                 record->bytenr, 0,
2574                                                 &record->old_roots, false);
2575                                 if (ret < 0)
2576                                         goto cleanup;
2577                         }
2578
2579                         /*
2580                          * Use SEQ_LAST as time_seq to do special search, which
2581                          * doesn't lock tree or delayed_refs and search current
2582                          * root. It's safe inside commit_transaction().
2583                          */
2584                         ret = btrfs_find_all_roots(trans, fs_info,
2585                                 record->bytenr, SEQ_LAST, &new_roots, false);
2586                         if (ret < 0)
2587                                 goto cleanup;
2588                         if (qgroup_to_skip) {
2589                                 ulist_del(new_roots, qgroup_to_skip, 0);
2590                                 ulist_del(record->old_roots, qgroup_to_skip,
2591                                           0);
2592                         }
2593                         ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2594                                                           record->num_bytes,
2595                                                           record->old_roots,
2596                                                           new_roots);
2597                         record->old_roots = NULL;
2598                         new_roots = NULL;
2599                 }
2600 cleanup:
2601                 ulist_free(record->old_roots);
2602                 ulist_free(new_roots);
2603                 new_roots = NULL;
2604                 rb_erase(node, &delayed_refs->dirty_extent_root);
2605                 kfree(record);
2606
2607         }
2608         trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2609                                        num_dirty_extents);
2610         return ret;
2611 }
2612
2613 /*
2614  * called from commit_transaction. Writes all changed qgroups to disk.
2615  */
2616 int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
2617 {
2618         struct btrfs_fs_info *fs_info = trans->fs_info;
2619         struct btrfs_root *quota_root = fs_info->quota_root;
2620         int ret = 0;
2621
2622         if (!quota_root)
2623                 return ret;
2624
2625         spin_lock(&fs_info->qgroup_lock);
2626         while (!list_empty(&fs_info->dirty_qgroups)) {
2627                 struct btrfs_qgroup *qgroup;
2628                 qgroup = list_first_entry(&fs_info->dirty_qgroups,
2629                                           struct btrfs_qgroup, dirty);
2630                 list_del_init(&qgroup->dirty);
2631                 spin_unlock(&fs_info->qgroup_lock);
2632                 ret = update_qgroup_info_item(trans, qgroup);
2633                 if (ret)
2634                         fs_info->qgroup_flags |=
2635                                         BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2636                 ret = update_qgroup_limit_item(trans, qgroup);
2637                 if (ret)
2638                         fs_info->qgroup_flags |=
2639                                         BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2640                 spin_lock(&fs_info->qgroup_lock);
2641         }
2642         if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2643                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
2644         else
2645                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
2646         spin_unlock(&fs_info->qgroup_lock);
2647
2648         ret = update_qgroup_status_item(trans);
2649         if (ret)
2650                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2651
2652         return ret;
2653 }
2654
2655 /*
2656  * Copy the accounting information between qgroups. This is necessary
2657  * when a snapshot or a subvolume is created. Throwing an error will
2658  * cause a transaction abort so we take extra care here to only error
2659  * when a readonly fs is a reasonable outcome.
2660  */
2661 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
2662                          u64 objectid, struct btrfs_qgroup_inherit *inherit)
2663 {
2664         int ret = 0;
2665         int i;
2666         u64 *i_qgroups;
2667         struct btrfs_fs_info *fs_info = trans->fs_info;
2668         struct btrfs_root *quota_root;
2669         struct btrfs_qgroup *srcgroup;
2670         struct btrfs_qgroup *dstgroup;
2671         u32 level_size = 0;
2672         u64 nums;
2673
2674         mutex_lock(&fs_info->qgroup_ioctl_lock);
2675         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2676                 goto out;
2677
2678         quota_root = fs_info->quota_root;
2679         if (!quota_root) {
2680                 ret = -EINVAL;
2681                 goto out;
2682         }
2683
2684         if (inherit) {
2685                 i_qgroups = (u64 *)(inherit + 1);
2686                 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
2687                        2 * inherit->num_excl_copies;
2688                 for (i = 0; i < nums; ++i) {
2689                         srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
2690
2691                         /*
2692                          * Zero out invalid groups so we can ignore
2693                          * them later.
2694                          */
2695                         if (!srcgroup ||
2696                             ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
2697                                 *i_qgroups = 0ULL;
2698
2699                         ++i_qgroups;
2700                 }
2701         }
2702
2703         /*
2704          * create a tracking group for the subvol itself
2705          */
2706         ret = add_qgroup_item(trans, quota_root, objectid);
2707         if (ret)
2708                 goto out;
2709
2710         /*
2711          * add qgroup to all inherited groups
2712          */
2713         if (inherit) {
2714                 i_qgroups = (u64 *)(inherit + 1);
2715                 for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
2716                         if (*i_qgroups == 0)
2717                                 continue;
2718                         ret = add_qgroup_relation_item(trans, objectid,
2719                                                        *i_qgroups);
2720                         if (ret && ret != -EEXIST)
2721                                 goto out;
2722                         ret = add_qgroup_relation_item(trans, *i_qgroups,
2723                                                        objectid);
2724                         if (ret && ret != -EEXIST)
2725                                 goto out;
2726                 }
2727                 ret = 0;
2728         }
2729
2730
2731         spin_lock(&fs_info->qgroup_lock);
2732
2733         dstgroup = add_qgroup_rb(fs_info, objectid);
2734         if (IS_ERR(dstgroup)) {
2735                 ret = PTR_ERR(dstgroup);
2736                 goto unlock;
2737         }
2738
2739         if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
2740                 dstgroup->lim_flags = inherit->lim.flags;
2741                 dstgroup->max_rfer = inherit->lim.max_rfer;
2742                 dstgroup->max_excl = inherit->lim.max_excl;
2743                 dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
2744                 dstgroup->rsv_excl = inherit->lim.rsv_excl;
2745
2746                 ret = update_qgroup_limit_item(trans, dstgroup);
2747                 if (ret) {
2748                         fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2749                         btrfs_info(fs_info,
2750                                    "unable to update quota limit for %llu",
2751                                    dstgroup->qgroupid);
2752                         goto unlock;
2753                 }
2754         }
2755
2756         if (srcid) {
2757                 srcgroup = find_qgroup_rb(fs_info, srcid);
2758                 if (!srcgroup)
2759                         goto unlock;
2760
2761                 /*
2762                  * We call inherit after we clone the root in order to make sure
2763                  * our counts don't go crazy, so at this point the only
2764                  * difference between the two roots should be the root node.
2765                  */
2766                 level_size = fs_info->nodesize;
2767                 dstgroup->rfer = srcgroup->rfer;
2768                 dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
2769                 dstgroup->excl = level_size;
2770                 dstgroup->excl_cmpr = level_size;
2771                 srcgroup->excl = level_size;
2772                 srcgroup->excl_cmpr = level_size;
2773
2774                 /* inherit the limit info */
2775                 dstgroup->lim_flags = srcgroup->lim_flags;
2776                 dstgroup->max_rfer = srcgroup->max_rfer;
2777                 dstgroup->max_excl = srcgroup->max_excl;
2778                 dstgroup->rsv_rfer = srcgroup->rsv_rfer;
2779                 dstgroup->rsv_excl = srcgroup->rsv_excl;
2780
2781                 qgroup_dirty(fs_info, dstgroup);
2782                 qgroup_dirty(fs_info, srcgroup);
2783         }
2784
2785         if (!inherit)
2786                 goto unlock;
2787
2788         i_qgroups = (u64 *)(inherit + 1);
2789         for (i = 0; i < inherit->num_qgroups; ++i) {
2790                 if (*i_qgroups) {
2791                         ret = add_relation_rb(fs_info, objectid, *i_qgroups);
2792                         if (ret)
2793                                 goto unlock;
2794                 }
2795                 ++i_qgroups;
2796         }
2797
2798         for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
2799                 struct btrfs_qgroup *src;
2800                 struct btrfs_qgroup *dst;
2801
2802                 if (!i_qgroups[0] || !i_qgroups[1])
2803                         continue;
2804
2805                 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2806                 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2807
2808                 if (!src || !dst) {
2809                         ret = -EINVAL;
2810                         goto unlock;
2811                 }
2812
2813                 dst->rfer = src->rfer - level_size;
2814                 dst->rfer_cmpr = src->rfer_cmpr - level_size;
2815         }
2816         for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
2817                 struct btrfs_qgroup *src;
2818                 struct btrfs_qgroup *dst;
2819
2820                 if (!i_qgroups[0] || !i_qgroups[1])
2821                         continue;
2822
2823                 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2824                 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2825
2826                 if (!src || !dst) {
2827                         ret = -EINVAL;
2828                         goto unlock;
2829                 }
2830
2831                 dst->excl = src->excl + level_size;
2832                 dst->excl_cmpr = src->excl_cmpr + level_size;
2833         }
2834
2835 unlock:
2836         spin_unlock(&fs_info->qgroup_lock);
2837 out:
2838         mutex_unlock(&fs_info->qgroup_ioctl_lock);
2839         return ret;
2840 }
2841
2842 /*
2843  * Two limits to commit transaction in advance.
2844  *
2845  * For RATIO, it will be 1/RATIO of the remaining limit
2846  * (excluding data and prealloc meta) as threshold.
2847  * For SIZE, it will be in byte unit as threshold.
2848  */
2849 #define QGROUP_PERTRANS_RATIO           32
2850 #define QGROUP_PERTRANS_SIZE            SZ_32M
2851 static bool qgroup_check_limits(struct btrfs_fs_info *fs_info,
2852                                 const struct btrfs_qgroup *qg, u64 num_bytes)
2853 {
2854         u64 limit;
2855         u64 threshold;
2856
2857         if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2858             qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
2859                 return false;
2860
2861         if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2862             qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
2863                 return false;
2864
2865         /*
2866          * Even if we passed the check, it's better to check if reservation
2867          * for meta_pertrans is pushing us near limit.
2868          * If there is too much pertrans reservation or it's near the limit,
2869          * let's try commit transaction to free some, using transaction_kthread
2870          */
2871         if ((qg->lim_flags & (BTRFS_QGROUP_LIMIT_MAX_RFER |
2872                               BTRFS_QGROUP_LIMIT_MAX_EXCL))) {
2873                 if (qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL)
2874                         limit = qg->max_excl;
2875                 else
2876                         limit = qg->max_rfer;
2877                 threshold = (limit - qg->rsv.values[BTRFS_QGROUP_RSV_DATA] -
2878                             qg->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC]) /
2879                             QGROUP_PERTRANS_RATIO;
2880                 threshold = min_t(u64, threshold, QGROUP_PERTRANS_SIZE);
2881
2882                 /*
2883                  * Use transaction_kthread to commit transaction, so we no
2884                  * longer need to bother nested transaction nor lock context.
2885                  */
2886                 if (qg->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > threshold)
2887                         btrfs_commit_transaction_locksafe(fs_info);
2888         }
2889
2890         return true;
2891 }
2892
2893 static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
2894                           enum btrfs_qgroup_rsv_type type)
2895 {
2896         struct btrfs_root *quota_root;
2897         struct btrfs_qgroup *qgroup;
2898         struct btrfs_fs_info *fs_info = root->fs_info;
2899         u64 ref_root = root->root_key.objectid;
2900         int ret = 0;
2901         struct ulist_node *unode;
2902         struct ulist_iterator uiter;
2903
2904         if (!is_fstree(ref_root))
2905                 return 0;
2906
2907         if (num_bytes == 0)
2908                 return 0;
2909
2910         if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
2911             capable(CAP_SYS_RESOURCE))
2912                 enforce = false;
2913
2914         spin_lock(&fs_info->qgroup_lock);
2915         quota_root = fs_info->quota_root;
2916         if (!quota_root)
2917                 goto out;
2918
2919         qgroup = find_qgroup_rb(fs_info, ref_root);
2920         if (!qgroup)
2921                 goto out;
2922
2923         /*
2924          * in a first step, we check all affected qgroups if any limits would
2925          * be exceeded
2926          */
2927         ulist_reinit(fs_info->qgroup_ulist);
2928         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2929                         qgroup_to_aux(qgroup), GFP_ATOMIC);
2930         if (ret < 0)
2931                 goto out;
2932         ULIST_ITER_INIT(&uiter);
2933         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2934                 struct btrfs_qgroup *qg;
2935                 struct btrfs_qgroup_list *glist;
2936
2937                 qg = unode_aux_to_qgroup(unode);
2938
2939                 if (enforce && !qgroup_check_limits(fs_info, qg, num_bytes)) {
2940                         ret = -EDQUOT;
2941                         goto out;
2942                 }
2943
2944                 list_for_each_entry(glist, &qg->groups, next_group) {
2945                         ret = ulist_add(fs_info->qgroup_ulist,
2946                                         glist->group->qgroupid,
2947                                         qgroup_to_aux(glist->group), GFP_ATOMIC);
2948                         if (ret < 0)
2949                                 goto out;
2950                 }
2951         }
2952         ret = 0;
2953         /*
2954          * no limits exceeded, now record the reservation into all qgroups
2955          */
2956         ULIST_ITER_INIT(&uiter);
2957         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2958                 struct btrfs_qgroup *qg;
2959
2960                 qg = unode_aux_to_qgroup(unode);
2961
2962                 trace_qgroup_update_reserve(fs_info, qg, num_bytes, type);
2963                 qgroup_rsv_add(fs_info, qg, num_bytes, type);
2964         }
2965
2966 out:
2967         spin_unlock(&fs_info->qgroup_lock);
2968         return ret;
2969 }
2970
2971 /*
2972  * Free @num_bytes of reserved space with @type for qgroup.  (Normally level 0
2973  * qgroup).
2974  *
2975  * Will handle all higher level qgroup too.
2976  *
2977  * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
2978  * This special case is only used for META_PERTRANS type.
2979  */
2980 void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
2981                                u64 ref_root, u64 num_bytes,
2982                                enum btrfs_qgroup_rsv_type type)
2983 {
2984         struct btrfs_root *quota_root;
2985         struct btrfs_qgroup *qgroup;
2986         struct ulist_node *unode;
2987         struct ulist_iterator uiter;
2988         int ret = 0;
2989
2990         if (!is_fstree(ref_root))
2991                 return;
2992
2993         if (num_bytes == 0)
2994                 return;
2995
2996         if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
2997                 WARN(1, "%s: Invalid type to free", __func__);
2998                 return;
2999         }
3000         spin_lock(&fs_info->qgroup_lock);
3001
3002         quota_root = fs_info->quota_root;
3003         if (!quota_root)
3004                 goto out;
3005
3006         qgroup = find_qgroup_rb(fs_info, ref_root);
3007         if (!qgroup)
3008                 goto out;
3009
3010         if (num_bytes == (u64)-1)
3011                 /*
3012                  * We're freeing all pertrans rsv, get reserved value from
3013                  * level 0 qgroup as real num_bytes to free.
3014                  */
3015                 num_bytes = qgroup->rsv.values[type];
3016
3017         ulist_reinit(fs_info->qgroup_ulist);
3018         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3019                         qgroup_to_aux(qgroup), GFP_ATOMIC);
3020         if (ret < 0)
3021                 goto out;
3022         ULIST_ITER_INIT(&uiter);
3023         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3024                 struct btrfs_qgroup *qg;
3025                 struct btrfs_qgroup_list *glist;
3026
3027                 qg = unode_aux_to_qgroup(unode);
3028
3029                 trace_qgroup_update_reserve(fs_info, qg, -(s64)num_bytes, type);
3030                 qgroup_rsv_release(fs_info, qg, num_bytes, type);
3031
3032                 list_for_each_entry(glist, &qg->groups, next_group) {
3033                         ret = ulist_add(fs_info->qgroup_ulist,
3034                                         glist->group->qgroupid,
3035                                         qgroup_to_aux(glist->group), GFP_ATOMIC);
3036                         if (ret < 0)
3037                                 goto out;
3038                 }
3039         }
3040
3041 out:
3042         spin_unlock(&fs_info->qgroup_lock);
3043 }
3044
3045 /*
3046  * Check if the leaf is the last leaf. Which means all node pointers
3047  * are at their last position.
3048  */
3049 static bool is_last_leaf(struct btrfs_path *path)
3050 {
3051         int i;
3052
3053         for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3054                 if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3055                         return false;
3056         }
3057         return true;
3058 }
3059
3060 /*
3061  * returns < 0 on error, 0 when more leafs are to be scanned.
3062  * returns 1 when done.
3063  */
3064 static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3065                               struct btrfs_path *path)
3066 {
3067         struct btrfs_fs_info *fs_info = trans->fs_info;
3068         struct btrfs_key found;
3069         struct extent_buffer *scratch_leaf = NULL;
3070         struct ulist *roots = NULL;
3071         u64 num_bytes;
3072         bool done;
3073         int slot;
3074         int ret;
3075
3076         mutex_lock(&fs_info->qgroup_rescan_lock);
3077         ret = btrfs_search_slot_for_read(fs_info->extent_root,
3078                                          &fs_info->qgroup_rescan_progress,
3079                                          path, 1, 0);
3080
3081         btrfs_debug(fs_info,
3082                 "current progress key (%llu %u %llu), search_slot ret %d",
3083                 fs_info->qgroup_rescan_progress.objectid,
3084                 fs_info->qgroup_rescan_progress.type,
3085                 fs_info->qgroup_rescan_progress.offset, ret);
3086
3087         if (ret) {
3088                 /*
3089                  * The rescan is about to end, we will not be scanning any
3090                  * further blocks. We cannot unset the RESCAN flag here, because
3091                  * we want to commit the transaction if everything went well.
3092                  * To make the live accounting work in this phase, we set our
3093                  * scan progress pointer such that every real extent objectid
3094                  * will be smaller.
3095                  */
3096                 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3097                 btrfs_release_path(path);
3098                 mutex_unlock(&fs_info->qgroup_rescan_lock);
3099                 return ret;
3100         }
3101         done = is_last_leaf(path);
3102
3103         btrfs_item_key_to_cpu(path->nodes[0], &found,
3104                               btrfs_header_nritems(path->nodes[0]) - 1);
3105         fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3106
3107         scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3108         if (!scratch_leaf) {
3109                 ret = -ENOMEM;
3110                 mutex_unlock(&fs_info->qgroup_rescan_lock);
3111                 goto out;
3112         }
3113         slot = path->slots[0];
3114         btrfs_release_path(path);
3115         mutex_unlock(&fs_info->qgroup_rescan_lock);
3116
3117         for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
3118                 btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3119                 if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3120                     found.type != BTRFS_METADATA_ITEM_KEY)
3121                         continue;
3122                 if (found.type == BTRFS_METADATA_ITEM_KEY)
3123                         num_bytes = fs_info->nodesize;
3124                 else
3125                         num_bytes = found.offset;
3126
3127                 ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
3128                                            &roots, false);
3129                 if (ret < 0)
3130                         goto out;
3131                 /* For rescan, just pass old_roots as NULL */
3132                 ret = btrfs_qgroup_account_extent(trans, found.objectid,
3133                                                   num_bytes, NULL, roots);
3134                 if (ret < 0)
3135                         goto out;
3136         }
3137 out:
3138         if (scratch_leaf)
3139                 free_extent_buffer(scratch_leaf);
3140
3141         if (done && !ret) {
3142                 ret = 1;
3143                 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3144         }
3145         return ret;
3146 }
3147
3148 static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3149 {
3150         struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3151                                                      qgroup_rescan_work);
3152         struct btrfs_path *path;
3153         struct btrfs_trans_handle *trans = NULL;
3154         int err = -ENOMEM;
3155         int ret = 0;
3156
3157         path = btrfs_alloc_path();
3158         if (!path)
3159                 goto out;
3160         /*
3161          * Rescan should only search for commit root, and any later difference
3162          * should be recorded by qgroup
3163          */
3164         path->search_commit_root = 1;
3165         path->skip_locking = 1;
3166
3167         err = 0;
3168         while (!err && !btrfs_fs_closing(fs_info)) {
3169                 trans = btrfs_start_transaction(fs_info->fs_root, 0);
3170                 if (IS_ERR(trans)) {
3171                         err = PTR_ERR(trans);
3172                         break;
3173                 }
3174                 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
3175                         err = -EINTR;
3176                 } else {
3177                         err = qgroup_rescan_leaf(trans, path);
3178                 }
3179                 if (err > 0)
3180                         btrfs_commit_transaction(trans);
3181                 else
3182                         btrfs_end_transaction(trans);
3183         }
3184
3185 out:
3186         btrfs_free_path(path);
3187
3188         mutex_lock(&fs_info->qgroup_rescan_lock);
3189         if (!btrfs_fs_closing(fs_info))
3190                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3191
3192         if (err > 0 &&
3193             fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3194                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3195         } else if (err < 0) {
3196                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3197         }
3198         mutex_unlock(&fs_info->qgroup_rescan_lock);
3199
3200         /*
3201          * only update status, since the previous part has already updated the
3202          * qgroup info.
3203          */
3204         trans = btrfs_start_transaction(fs_info->quota_root, 1);
3205         if (IS_ERR(trans)) {
3206                 err = PTR_ERR(trans);
3207                 btrfs_err(fs_info,
3208                           "fail to start transaction for status update: %d",
3209                           err);
3210                 goto done;
3211         }
3212         ret = update_qgroup_status_item(trans);
3213         if (ret < 0) {
3214                 err = ret;
3215                 btrfs_err(fs_info, "fail to update qgroup status: %d", err);
3216         }
3217         btrfs_end_transaction(trans);
3218
3219         if (btrfs_fs_closing(fs_info)) {
3220                 btrfs_info(fs_info, "qgroup scan paused");
3221         } else if (err >= 0) {
3222                 btrfs_info(fs_info, "qgroup scan completed%s",
3223                         err > 0 ? " (inconsistency flag cleared)" : "");
3224         } else {
3225                 btrfs_err(fs_info, "qgroup scan failed with %d", err);
3226         }
3227
3228 done:
3229         mutex_lock(&fs_info->qgroup_rescan_lock);
3230         fs_info->qgroup_rescan_running = false;
3231         mutex_unlock(&fs_info->qgroup_rescan_lock);
3232         complete_all(&fs_info->qgroup_rescan_completion);
3233 }
3234
3235 /*
3236  * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3237  * memory required for the rescan context.
3238  */
3239 static int
3240 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3241                    int init_flags)
3242 {
3243         int ret = 0;
3244
3245         if (!init_flags) {
3246                 /* we're resuming qgroup rescan at mount time */
3247                 if (!(fs_info->qgroup_flags &
3248                       BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3249                         btrfs_warn(fs_info,
3250                         "qgroup rescan init failed, qgroup is not enabled");
3251                         ret = -EINVAL;
3252                 } else if (!(fs_info->qgroup_flags &
3253                              BTRFS_QGROUP_STATUS_FLAG_ON)) {
3254                         btrfs_warn(fs_info,
3255                         "qgroup rescan init failed, qgroup rescan is not queued");
3256                         ret = -EINVAL;
3257                 }
3258
3259                 if (ret)
3260                         return ret;
3261         }
3262
3263         mutex_lock(&fs_info->qgroup_rescan_lock);
3264         spin_lock(&fs_info->qgroup_lock);
3265
3266         if (init_flags) {
3267                 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3268                         btrfs_warn(fs_info,
3269                                    "qgroup rescan is already in progress");
3270                         ret = -EINPROGRESS;
3271                 } else if (!(fs_info->qgroup_flags &
3272                              BTRFS_QGROUP_STATUS_FLAG_ON)) {
3273                         btrfs_warn(fs_info,
3274                         "qgroup rescan init failed, qgroup is not enabled");
3275                         ret = -EINVAL;
3276                 }
3277
3278                 if (ret) {
3279                         spin_unlock(&fs_info->qgroup_lock);
3280                         mutex_unlock(&fs_info->qgroup_rescan_lock);
3281                         return ret;
3282                 }
3283                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3284         }
3285
3286         memset(&fs_info->qgroup_rescan_progress, 0,
3287                 sizeof(fs_info->qgroup_rescan_progress));
3288         fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3289         init_completion(&fs_info->qgroup_rescan_completion);
3290         fs_info->qgroup_rescan_running = true;
3291
3292         spin_unlock(&fs_info->qgroup_lock);
3293         mutex_unlock(&fs_info->qgroup_rescan_lock);
3294
3295         memset(&fs_info->qgroup_rescan_work, 0,
3296                sizeof(fs_info->qgroup_rescan_work));
3297         btrfs_init_work(&fs_info->qgroup_rescan_work,
3298                         btrfs_qgroup_rescan_helper,
3299                         btrfs_qgroup_rescan_worker, NULL, NULL);
3300         return 0;
3301 }
3302
3303 static void
3304 qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3305 {
3306         struct rb_node *n;
3307         struct btrfs_qgroup *qgroup;
3308
3309         spin_lock(&fs_info->qgroup_lock);
3310         /* clear all current qgroup tracking information */
3311         for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3312                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
3313                 qgroup->rfer = 0;
3314                 qgroup->rfer_cmpr = 0;
3315                 qgroup->excl = 0;
3316                 qgroup->excl_cmpr = 0;
3317                 qgroup_dirty(fs_info, qgroup);
3318         }
3319         spin_unlock(&fs_info->qgroup_lock);
3320 }
3321
3322 int
3323 btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3324 {
3325         int ret = 0;
3326         struct btrfs_trans_handle *trans;
3327
3328         ret = qgroup_rescan_init(fs_info, 0, 1);
3329         if (ret)
3330                 return ret;
3331
3332         /*
3333          * We have set the rescan_progress to 0, which means no more
3334          * delayed refs will be accounted by btrfs_qgroup_account_ref.
3335          * However, btrfs_qgroup_account_ref may be right after its call
3336          * to btrfs_find_all_roots, in which case it would still do the
3337          * accounting.
3338          * To solve this, we're committing the transaction, which will
3339          * ensure we run all delayed refs and only after that, we are
3340          * going to clear all tracking information for a clean start.
3341          */
3342
3343         trans = btrfs_join_transaction(fs_info->fs_root);
3344         if (IS_ERR(trans)) {
3345                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3346                 return PTR_ERR(trans);
3347         }
3348         ret = btrfs_commit_transaction(trans);
3349         if (ret) {
3350                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3351                 return ret;
3352         }
3353
3354         qgroup_rescan_zero_tracking(fs_info);
3355
3356         btrfs_queue_work(fs_info->qgroup_rescan_workers,
3357                          &fs_info->qgroup_rescan_work);
3358
3359         return 0;
3360 }
3361
3362 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3363                                      bool interruptible)
3364 {
3365         int running;
3366         int ret = 0;
3367
3368         mutex_lock(&fs_info->qgroup_rescan_lock);
3369         spin_lock(&fs_info->qgroup_lock);
3370         running = fs_info->qgroup_rescan_running;
3371         spin_unlock(&fs_info->qgroup_lock);
3372         mutex_unlock(&fs_info->qgroup_rescan_lock);
3373
3374         if (!running)
3375                 return 0;
3376
3377         if (interruptible)
3378                 ret = wait_for_completion_interruptible(
3379                                         &fs_info->qgroup_rescan_completion);
3380         else
3381                 wait_for_completion(&fs_info->qgroup_rescan_completion);
3382
3383         return ret;
3384 }
3385
3386 /*
3387  * this is only called from open_ctree where we're still single threaded, thus
3388  * locking is omitted here.
3389  */
3390 void
3391 btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3392 {
3393         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
3394                 btrfs_queue_work(fs_info->qgroup_rescan_workers,
3395                                  &fs_info->qgroup_rescan_work);
3396 }
3397
3398 /*
3399  * Reserve qgroup space for range [start, start + len).
3400  *
3401  * This function will either reserve space from related qgroups or doing
3402  * nothing if the range is already reserved.
3403  *
3404  * Return 0 for successful reserve
3405  * Return <0 for error (including -EQUOT)
3406  *
3407  * NOTE: this function may sleep for memory allocation.
3408  *       if btrfs_qgroup_reserve_data() is called multiple times with
3409  *       same @reserved, caller must ensure when error happens it's OK
3410  *       to free *ALL* reserved space.
3411  */
3412 int btrfs_qgroup_reserve_data(struct inode *inode,
3413                         struct extent_changeset **reserved_ret, u64 start,
3414                         u64 len)
3415 {
3416         struct btrfs_root *root = BTRFS_I(inode)->root;
3417         struct ulist_node *unode;
3418         struct ulist_iterator uiter;
3419         struct extent_changeset *reserved;
3420         u64 orig_reserved;
3421         u64 to_reserve;
3422         int ret;
3423
3424         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags) ||
3425             !is_fstree(root->root_key.objectid) || len == 0)
3426                 return 0;
3427
3428         /* @reserved parameter is mandatory for qgroup */
3429         if (WARN_ON(!reserved_ret))
3430                 return -EINVAL;
3431         if (!*reserved_ret) {
3432                 *reserved_ret = extent_changeset_alloc();
3433                 if (!*reserved_ret)
3434                         return -ENOMEM;
3435         }
3436         reserved = *reserved_ret;
3437         /* Record already reserved space */
3438         orig_reserved = reserved->bytes_changed;
3439         ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
3440                         start + len -1, EXTENT_QGROUP_RESERVED, reserved);
3441
3442         /* Newly reserved space */
3443         to_reserve = reserved->bytes_changed - orig_reserved;
3444         trace_btrfs_qgroup_reserve_data(inode, start, len,
3445                                         to_reserve, QGROUP_RESERVE);
3446         if (ret < 0)
3447                 goto cleanup;
3448         ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
3449         if (ret < 0)
3450                 goto cleanup;
3451
3452         return ret;
3453
3454 cleanup:
3455         /* cleanup *ALL* already reserved ranges */
3456         ULIST_ITER_INIT(&uiter);
3457         while ((unode = ulist_next(&reserved->range_changed, &uiter)))
3458                 clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val,
3459                                  unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL);
3460         extent_changeset_release(reserved);
3461         return ret;
3462 }
3463
3464 /* Free ranges specified by @reserved, normally in error path */
3465 static int qgroup_free_reserved_data(struct inode *inode,
3466                         struct extent_changeset *reserved, u64 start, u64 len)
3467 {
3468         struct btrfs_root *root = BTRFS_I(inode)->root;
3469         struct ulist_node *unode;
3470         struct ulist_iterator uiter;
3471         struct extent_changeset changeset;
3472         int freed = 0;
3473         int ret;
3474
3475         extent_changeset_init(&changeset);
3476         len = round_up(start + len, root->fs_info->sectorsize);
3477         start = round_down(start, root->fs_info->sectorsize);
3478
3479         ULIST_ITER_INIT(&uiter);
3480         while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
3481                 u64 range_start = unode->val;
3482                 /* unode->aux is the inclusive end */
3483                 u64 range_len = unode->aux - range_start + 1;
3484                 u64 free_start;
3485                 u64 free_len;
3486
3487                 extent_changeset_release(&changeset);
3488
3489                 /* Only free range in range [start, start + len) */
3490                 if (range_start >= start + len ||
3491                     range_start + range_len <= start)
3492                         continue;
3493                 free_start = max(range_start, start);
3494                 free_len = min(start + len, range_start + range_len) -
3495                            free_start;
3496                 /*
3497                  * TODO: To also modify reserved->ranges_reserved to reflect
3498                  * the modification.
3499                  *
3500                  * However as long as we free qgroup reserved according to
3501                  * EXTENT_QGROUP_RESERVED, we won't double free.
3502                  * So not need to rush.
3503                  */
3504                 ret = clear_record_extent_bits(&BTRFS_I(inode)->io_failure_tree,
3505                                 free_start, free_start + free_len - 1,
3506                                 EXTENT_QGROUP_RESERVED, &changeset);
3507                 if (ret < 0)
3508                         goto out;
3509                 freed += changeset.bytes_changed;
3510         }
3511         btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
3512                                   BTRFS_QGROUP_RSV_DATA);
3513         ret = freed;
3514 out:
3515         extent_changeset_release(&changeset);
3516         return ret;
3517 }
3518
3519 static int __btrfs_qgroup_release_data(struct inode *inode,
3520                         struct extent_changeset *reserved, u64 start, u64 len,
3521                         int free)
3522 {
3523         struct extent_changeset changeset;
3524         int trace_op = QGROUP_RELEASE;
3525         int ret;
3526
3527         if (!test_bit(BTRFS_FS_QUOTA_ENABLED,
3528                       &BTRFS_I(inode)->root->fs_info->flags))
3529                 return 0;
3530
3531         /* In release case, we shouldn't have @reserved */
3532         WARN_ON(!free && reserved);
3533         if (free && reserved)
3534                 return qgroup_free_reserved_data(inode, reserved, start, len);
3535         extent_changeset_init(&changeset);
3536         ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
3537                         start + len -1, EXTENT_QGROUP_RESERVED, &changeset);
3538         if (ret < 0)
3539                 goto out;
3540
3541         if (free)
3542                 trace_op = QGROUP_FREE;
3543         trace_btrfs_qgroup_release_data(inode, start, len,
3544                                         changeset.bytes_changed, trace_op);
3545         if (free)
3546                 btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
3547                                 BTRFS_I(inode)->root->root_key.objectid,
3548                                 changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3549         ret = changeset.bytes_changed;
3550 out:
3551         extent_changeset_release(&changeset);
3552         return ret;
3553 }
3554
3555 /*
3556  * Free a reserved space range from io_tree and related qgroups
3557  *
3558  * Should be called when a range of pages get invalidated before reaching disk.
3559  * Or for error cleanup case.
3560  * if @reserved is given, only reserved range in [@start, @start + @len) will
3561  * be freed.
3562  *
3563  * For data written to disk, use btrfs_qgroup_release_data().
3564  *
3565  * NOTE: This function may sleep for memory allocation.
3566  */
3567 int btrfs_qgroup_free_data(struct inode *inode,
3568                         struct extent_changeset *reserved, u64 start, u64 len)
3569 {
3570         return __btrfs_qgroup_release_data(inode, reserved, start, len, 1);
3571 }
3572
3573 /*
3574  * Release a reserved space range from io_tree only.
3575  *
3576  * Should be called when a range of pages get written to disk and corresponding
3577  * FILE_EXTENT is inserted into corresponding root.
3578  *
3579  * Since new qgroup accounting framework will only update qgroup numbers at
3580  * commit_transaction() time, its reserved space shouldn't be freed from
3581  * related qgroups.
3582  *
3583  * But we should release the range from io_tree, to allow further write to be
3584  * COWed.
3585  *
3586  * NOTE: This function may sleep for memory allocation.
3587  */
3588 int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
3589 {
3590         return __btrfs_qgroup_release_data(inode, NULL, start, len, 0);
3591 }
3592
3593 static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3594                               enum btrfs_qgroup_rsv_type type)
3595 {
3596         if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3597             type != BTRFS_QGROUP_RSV_META_PERTRANS)
3598                 return;
3599         if (num_bytes == 0)
3600                 return;
3601
3602         spin_lock(&root->qgroup_meta_rsv_lock);
3603         if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
3604                 root->qgroup_meta_rsv_prealloc += num_bytes;
3605         else
3606                 root->qgroup_meta_rsv_pertrans += num_bytes;
3607         spin_unlock(&root->qgroup_meta_rsv_lock);
3608 }
3609
3610 static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3611                              enum btrfs_qgroup_rsv_type type)
3612 {
3613         if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3614             type != BTRFS_QGROUP_RSV_META_PERTRANS)
3615                 return 0;
3616         if (num_bytes == 0)
3617                 return 0;
3618
3619         spin_lock(&root->qgroup_meta_rsv_lock);
3620         if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
3621                 num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
3622                                   num_bytes);
3623                 root->qgroup_meta_rsv_prealloc -= num_bytes;
3624         } else {
3625                 num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
3626                                   num_bytes);
3627                 root->qgroup_meta_rsv_pertrans -= num_bytes;
3628         }
3629         spin_unlock(&root->qgroup_meta_rsv_lock);
3630         return num_bytes;
3631 }
3632
3633 int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
3634                                 enum btrfs_qgroup_rsv_type type, bool enforce)
3635 {
3636         struct btrfs_fs_info *fs_info = root->fs_info;
3637         int ret;
3638
3639         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3640             !is_fstree(root->root_key.objectid) || num_bytes == 0)
3641                 return 0;
3642
3643         BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
3644         trace_qgroup_meta_reserve(root, type, (s64)num_bytes);
3645         ret = qgroup_reserve(root, num_bytes, enforce, type);
3646         if (ret < 0)
3647                 return ret;
3648         /*
3649          * Record what we have reserved into root.
3650          *
3651          * To avoid quota disabled->enabled underflow.
3652          * In that case, we may try to free space we haven't reserved
3653          * (since quota was disabled), so record what we reserved into root.
3654          * And ensure later release won't underflow this number.
3655          */
3656         add_root_meta_rsv(root, num_bytes, type);
3657         return ret;
3658 }
3659
3660 void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
3661 {
3662         struct btrfs_fs_info *fs_info = root->fs_info;
3663
3664         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3665             !is_fstree(root->root_key.objectid))
3666                 return;
3667
3668         /* TODO: Update trace point to handle such free */
3669         trace_qgroup_meta_free_all_pertrans(root);
3670         /* Special value -1 means to free all reserved space */
3671         btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
3672                                   BTRFS_QGROUP_RSV_META_PERTRANS);
3673 }
3674
3675 void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
3676                               enum btrfs_qgroup_rsv_type type)
3677 {
3678         struct btrfs_fs_info *fs_info = root->fs_info;
3679
3680         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3681             !is_fstree(root->root_key.objectid))
3682                 return;
3683
3684         /*
3685          * reservation for META_PREALLOC can happen before quota is enabled,
3686          * which can lead to underflow.
3687          * Here ensure we will only free what we really have reserved.
3688          */
3689         num_bytes = sub_root_meta_rsv(root, num_bytes, type);
3690         BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
3691         trace_qgroup_meta_reserve(root, type, -(s64)num_bytes);
3692         btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
3693                                   num_bytes, type);
3694 }
3695
3696 static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
3697                                 int num_bytes)
3698 {
3699         struct btrfs_root *quota_root = fs_info->quota_root;
3700         struct btrfs_qgroup *qgroup;
3701         struct ulist_node *unode;
3702         struct ulist_iterator uiter;
3703         int ret = 0;
3704
3705         if (num_bytes == 0)
3706                 return;
3707         if (!quota_root)
3708                 return;
3709
3710         spin_lock(&fs_info->qgroup_lock);
3711         qgroup = find_qgroup_rb(fs_info, ref_root);
3712         if (!qgroup)
3713                 goto out;
3714         ulist_reinit(fs_info->qgroup_ulist);
3715         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3716                        qgroup_to_aux(qgroup), GFP_ATOMIC);
3717         if (ret < 0)
3718                 goto out;
3719         ULIST_ITER_INIT(&uiter);
3720         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3721                 struct btrfs_qgroup *qg;
3722                 struct btrfs_qgroup_list *glist;
3723
3724                 qg = unode_aux_to_qgroup(unode);
3725
3726                 qgroup_rsv_release(fs_info, qg, num_bytes,
3727                                 BTRFS_QGROUP_RSV_META_PREALLOC);
3728                 qgroup_rsv_add(fs_info, qg, num_bytes,
3729                                 BTRFS_QGROUP_RSV_META_PERTRANS);
3730                 list_for_each_entry(glist, &qg->groups, next_group) {
3731                         ret = ulist_add(fs_info->qgroup_ulist,
3732                                         glist->group->qgroupid,
3733                                         qgroup_to_aux(glist->group), GFP_ATOMIC);
3734                         if (ret < 0)
3735                                 goto out;
3736                 }
3737         }
3738 out:
3739         spin_unlock(&fs_info->qgroup_lock);
3740 }
3741
3742 void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
3743 {
3744         struct btrfs_fs_info *fs_info = root->fs_info;
3745
3746         if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3747             !is_fstree(root->root_key.objectid))
3748                 return;
3749         /* Same as btrfs_qgroup_free_meta_prealloc() */
3750         num_bytes = sub_root_meta_rsv(root, num_bytes,
3751                                       BTRFS_QGROUP_RSV_META_PREALLOC);
3752         trace_qgroup_meta_convert(root, num_bytes);
3753         qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
3754 }
3755
3756 /*
3757  * Check qgroup reserved space leaking, normally at destroy inode
3758  * time
3759  */
3760 void btrfs_qgroup_check_reserved_leak(struct inode *inode)
3761 {
3762         struct extent_changeset changeset;
3763         struct ulist_node *unode;
3764         struct ulist_iterator iter;
3765         int ret;
3766
3767         extent_changeset_init(&changeset);
3768         ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
3769                         EXTENT_QGROUP_RESERVED, &changeset);
3770
3771         WARN_ON(ret < 0);
3772         if (WARN_ON(changeset.bytes_changed)) {
3773                 ULIST_ITER_INIT(&iter);
3774                 while ((unode = ulist_next(&changeset.range_changed, &iter))) {
3775                         btrfs_warn(BTRFS_I(inode)->root->fs_info,
3776                                 "leaking qgroup reserved space, ino: %lu, start: %llu, end: %llu",
3777                                 inode->i_ino, unode->val, unode->aux);
3778                 }
3779                 btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
3780                                 BTRFS_I(inode)->root->root_key.objectid,
3781                                 changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3782
3783         }
3784         extent_changeset_release(&changeset);
3785 }