fs/btrfs/qgroup.c

   1 /*
   2  * Copyright (C) 2011 STRATO.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <linux/sched.h>
  20 #include <linux/pagemap.h>
  21 #include <linux/writeback.h>
  22 #include <linux/blkdev.h>
  23 #include <linux/rbtree.h>
  24 #include <linux/slab.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/btrfs.h>
  27
  28 #include "ctree.h"
  29 #include "transaction.h"
  30 #include "disk-io.h"
  31 #include "locking.h"
  32 #include "ulist.h"
  33 #include "backref.h"
  34 #include "extent_io.h"
  35 #include "qgroup.h"
  36
  37
  38 /* TODO XXX FIXME
  39  *  - subvol delete -> delete when ref goes to 0? delete limits also?
  40  *  - reorganize keys
  41  *  - compressed
  42  *  - sync
  43  *  - copy also limits on subvol creation
  44  *  - limit
  45  *  - caches fuer ulists
  46  *  - performance benchmarks
  47  *  - check all ioctl parameters
  48  */
  49
  50 /*
  51  * one struct for each qgroup, organized in fs_info->qgroup_tree.
  52  */
  53 struct btrfs_qgroup {
  54         u64 qgroupid;
  55
  56         /*
  57          * state
  58          */
  59         u64 rfer;       /* referenced */
  60         u64 rfer_cmpr;  /* referenced compressed */
  61         u64 excl;       /* exclusive */
  62         u64 excl_cmpr;  /* exclusive compressed */
  63
  64         /*
  65          * limits
  66          */
  67         u64 lim_flags;  /* which limits are set */
  68         u64 max_rfer;
  69         u64 max_excl;
  70         u64 rsv_rfer;
  71         u64 rsv_excl;
  72
  73         /*
  74          * reservation tracking
  75          */
  76         u64 reserved;
  77
  78         /*
  79          * lists
  80          */
  81         struct list_head groups;  /* groups this group is member of */
  82         struct list_head members; /* groups that are members of this group */
  83         struct list_head dirty;   /* dirty groups */
  84         struct rb_node node;      /* tree of qgroups */
  85
  86         /*
  87          * temp variables for accounting operations
  88          * Refer to qgroup_shared_accouting() for details.
  89          */
  90         u64 old_refcnt;
  91         u64 new_refcnt;
  92 };
  93
  94 static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
  95                                            int mod)
  96 {
  97         if (qg->old_refcnt < seq)
  98                 qg->old_refcnt = seq;
  99         qg->old_refcnt += mod;
 100 }
 101
 102 static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
 103                                            int mod)
 104 {
 105         if (qg->new_refcnt < seq)
 106                 qg->new_refcnt = seq;
 107         qg->new_refcnt += mod;
 108 }
 109
 110 static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
 111 {
 112         if (qg->old_refcnt < seq)
 113                 return 0;
 114         return qg->old_refcnt - seq;
 115 }
 116
 117 static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
 118 {
 119         if (qg->new_refcnt < seq)
 120                 return 0;
 121         return qg->new_refcnt - seq;
 122 }
 123
 124 /*
 125  * glue structure to represent the relations between qgroups.
 126  */
 127 struct btrfs_qgroup_list {
 128         struct list_head next_group;
 129         struct list_head next_member;
 130         struct btrfs_qgroup *group;
 131         struct btrfs_qgroup *member;
 132 };
 133
 134 #define ptr_to_u64(x) ((u64)(uintptr_t)x)
 135 #define u64_to_ptr(x) ((struct btrfs_qgroup *)(uintptr_t)x)
 136
 137 static int
 138 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
 139                    int init_flags);
 140 static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 141
 142 /* must be called with qgroup_ioctl_lock held */
 143 static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
 144                                            u64 qgroupid)
 145 {
 146         struct rb_node *n = fs_info->qgroup_tree.rb_node;
 147         struct btrfs_qgroup *qgroup;
 148
 149         while (n) {
 150                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
 151                 if (qgroup->qgroupid < qgroupid)
 152                         n = n->rb_left;
 153                 else if (qgroup->qgroupid > qgroupid)
 154                         n = n->rb_right;
 155                 else
 156                         return qgroup;
 157         }
 158         return NULL;
 159 }
 160
 161 /* must be called with qgroup_lock held */
 162 static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
 163                                           u64 qgroupid)
 164 {
 165         struct rb_node **p = &fs_info->qgroup_tree.rb_node;
 166         struct rb_node *parent = NULL;
 167         struct btrfs_qgroup *qgroup;
 168
 169         while (*p) {
 170                 parent = *p;
 171                 qgroup = rb_entry(parent, struct btrfs_qgroup, node);
 172
 173                 if (qgroup->qgroupid < qgroupid)
 174                         p = &(*p)->rb_left;
 175                 else if (qgroup->qgroupid > qgroupid)
 176                         p = &(*p)->rb_right;
 177                 else
 178                         return qgroup;
 179         }
 180
 181         qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
 182         if (!qgroup)
 183                 return ERR_PTR(-ENOMEM);
 184
 185         qgroup->qgroupid = qgroupid;
 186         INIT_LIST_HEAD(&qgroup->groups);
 187         INIT_LIST_HEAD(&qgroup->members);
 188         INIT_LIST_HEAD(&qgroup->dirty);
 189
 190         rb_link_node(&qgroup->node, parent, p);
 191         rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
 192
 193         return qgroup;
 194 }
 195
 196 static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
 197 {
 198         struct btrfs_qgroup_list *list;
 199
 200         list_del(&qgroup->dirty);
 201         while (!list_empty(&qgroup->groups)) {
 202                 list = list_first_entry(&qgroup->groups,
 203                                         struct btrfs_qgroup_list, next_group);
 204                 list_del(&list->next_group);
 205                 list_del(&list->next_member);
 206                 kfree(list);
 207         }
 208
 209         while (!list_empty(&qgroup->members)) {
 210                 list = list_first_entry(&qgroup->members,
 211                                         struct btrfs_qgroup_list, next_member);
 212                 list_del(&list->next_group);
 213                 list_del(&list->next_member);
 214                 kfree(list);
 215         }
 216         kfree(qgroup);
 217 }
 218
 219 /* must be called with qgroup_lock held */
 220 static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
 221 {
 222         struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
 223
 224         if (!qgroup)
 225                 return -ENOENT;
 226
 227         rb_erase(&qgroup->node, &fs_info->qgroup_tree);
 228         __del_qgroup_rb(qgroup);
 229         return 0;
 230 }
 231
 232 /* must be called with qgroup_lock held */
 233 static int add_relation_rb(struct btrfs_fs_info *fs_info,
 234                            u64 memberid, u64 parentid)
 235 {
 236         struct btrfs_qgroup *member;
 237         struct btrfs_qgroup *parent;
 238         struct btrfs_qgroup_list *list;
 239
 240         member = find_qgroup_rb(fs_info, memberid);
 241         parent = find_qgroup_rb(fs_info, parentid);
 242         if (!member || !parent)
 243                 return -ENOENT;
 244
 245         list = kzalloc(sizeof(*list), GFP_ATOMIC);
 246         if (!list)
 247                 return -ENOMEM;
 248
 249         list->group = parent;
 250         list->member = member;
 251         list_add_tail(&list->next_group, &member->groups);
 252         list_add_tail(&list->next_member, &parent->members);
 253
 254         return 0;
 255 }
 256
 257 /* must be called with qgroup_lock held */
 258 static int del_relation_rb(struct btrfs_fs_info *fs_info,
 259                            u64 memberid, u64 parentid)
 260 {
 261         struct btrfs_qgroup *member;
 262         struct btrfs_qgroup *parent;
 263         struct btrfs_qgroup_list *list;
 264
 265         member = find_qgroup_rb(fs_info, memberid);
 266         parent = find_qgroup_rb(fs_info, parentid);
 267         if (!member || !parent)
 268                 return -ENOENT;
 269
 270         list_for_each_entry(list, &member->groups, next_group) {
 271                 if (list->group == parent) {
 272                         list_del(&list->next_group);
 273                         list_del(&list->next_member);
 274                         kfree(list);
 275                         return 0;
 276                 }
 277         }
 278         return -ENOENT;
 279 }
 280
 281 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 282 int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
 283                                u64 rfer, u64 excl)
 284 {
 285         struct btrfs_qgroup *qgroup;
 286
 287         qgroup = find_qgroup_rb(fs_info, qgroupid);
 288         if (!qgroup)
 289                 return -EINVAL;
 290         if (qgroup->rfer != rfer || qgroup->excl != excl)
 291                 return -EINVAL;
 292         return 0;
 293 }
 294 #endif
 295
 296 /*
 297  * The full config is read in one go, only called from open_ctree()
 298  * It doesn't use any locking, as at this point we're still single-threaded
 299  */
 300 int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
 301 {
 302         struct btrfs_key key;
 303         struct btrfs_key found_key;
 304         struct btrfs_root *quota_root = fs_info->quota_root;
 305         struct btrfs_path *path = NULL;
 306         struct extent_buffer *l;
 307         int slot;
 308         int ret = 0;
 309         u64 flags = 0;
 310         u64 rescan_progress = 0;
 311
 312         if (!fs_info->quota_enabled)
 313                 return 0;
 314
 315         fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
 316         if (!fs_info->qgroup_ulist) {
 317                 ret = -ENOMEM;
 318                 goto out;
 319         }
 320
 321         path = btrfs_alloc_path();
 322         if (!path) {
 323                 ret = -ENOMEM;
 324                 goto out;
 325         }
 326
 327         /* default this to quota off, in case no status key is found */
 328         fs_info->qgroup_flags = 0;
 329
 330         /*
 331          * pass 1: read status, all qgroup infos and limits
 332          */
 333         key.objectid = 0;
 334         key.type = 0;
 335         key.offset = 0;
 336         ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
 337         if (ret)
 338                 goto out;
 339
 340         while (1) {
 341                 struct btrfs_qgroup *qgroup;
 342
 343                 slot = path->slots[0];
 344                 l = path->nodes[0];
 345                 btrfs_item_key_to_cpu(l, &found_key, slot);
 346
 347                 if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
 348                         struct btrfs_qgroup_status_item *ptr;
 349
 350                         ptr = btrfs_item_ptr(l, slot,
 351                                              struct btrfs_qgroup_status_item);
 352
 353                         if (btrfs_qgroup_status_version(l, ptr) !=
 354                             BTRFS_QGROUP_STATUS_VERSION) {
 355                                 btrfs_err(fs_info,
 356                                  "old qgroup version, quota disabled");
 357                                 goto out;
 358                         }
 359                         if (btrfs_qgroup_status_generation(l, ptr) !=
 360                             fs_info->generation) {
 361                                 flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 362                                 btrfs_err(fs_info,
 363                                         "qgroup generation mismatch, "
 364                                         "marked as inconsistent");
 365                         }
 366                         fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
 367                                                                           ptr);
 368                         rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
 369                         goto next1;
 370                 }
 371
 372                 if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
 373                     found_key.type != BTRFS_QGROUP_LIMIT_KEY)
 374                         goto next1;
 375
 376                 qgroup = find_qgroup_rb(fs_info, found_key.offset);
 377                 if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
 378                     (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
 379                         btrfs_err(fs_info, "inconsistent qgroup config");
 380                         flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 381                 }
 382                 if (!qgroup) {
 383                         qgroup = add_qgroup_rb(fs_info, found_key.offset);
 384                         if (IS_ERR(qgroup)) {
 385                                 ret = PTR_ERR(qgroup);
 386                                 goto out;
 387                         }
 388                 }
 389                 switch (found_key.type) {
 390                 case BTRFS_QGROUP_INFO_KEY: {
 391                         struct btrfs_qgroup_info_item *ptr;
 392
 393                         ptr = btrfs_item_ptr(l, slot,
 394                                              struct btrfs_qgroup_info_item);
 395                         qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
 396                         qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
 397                         qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
 398                         qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
 399                         /* generation currently unused */
 400                         break;
 401                 }
 402                 case BTRFS_QGROUP_LIMIT_KEY: {
 403                         struct btrfs_qgroup_limit_item *ptr;
 404
 405                         ptr = btrfs_item_ptr(l, slot,
 406                                              struct btrfs_qgroup_limit_item);
 407                         qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
 408                         qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
 409                         qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
 410                         qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
 411                         qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
 412                         break;
 413                 }
 414                 }
 415 next1:
 416                 ret = btrfs_next_item(quota_root, path);
 417                 if (ret < 0)
 418                         goto out;
 419                 if (ret)
 420                         break;
 421         }
 422         btrfs_release_path(path);
 423
 424         /*
 425          * pass 2: read all qgroup relations
 426          */
 427         key.objectid = 0;
 428         key.type = BTRFS_QGROUP_RELATION_KEY;
 429         key.offset = 0;
 430         ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
 431         if (ret)
 432                 goto out;
 433         while (1) {
 434                 slot = path->slots[0];
 435                 l = path->nodes[0];
 436                 btrfs_item_key_to_cpu(l, &found_key, slot);
 437
 438                 if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
 439                         goto next2;
 440
 441                 if (found_key.objectid > found_key.offset) {
 442                         /* parent <- member, not needed to build config */
 443                         /* FIXME should we omit the key completely? */
 444                         goto next2;
 445                 }
 446
 447                 ret = add_relation_rb(fs_info, found_key.objectid,
 448                                       found_key.offset);
 449                 if (ret == -ENOENT) {
 450                         btrfs_warn(fs_info,
 451                                 "orphan qgroup relation 0x%llx->0x%llx",
 452                                 found_key.objectid, found_key.offset);
 453                         ret = 0;        /* ignore the error */
 454                 }
 455                 if (ret)
 456                         goto out;
 457 next2:
 458                 ret = btrfs_next_item(quota_root, path);
 459                 if (ret < 0)
 460                         goto out;
 461                 if (ret)
 462                         break;
 463         }
 464 out:
 465         fs_info->qgroup_flags |= flags;
 466         if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)) {
 467                 fs_info->quota_enabled = 0;
 468                 fs_info->pending_quota_state = 0;
 469         } else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
 470                    ret >= 0) {
 471                 ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
 472         }
 473         btrfs_free_path(path);
 474
 475         if (ret < 0) {
 476                 ulist_free(fs_info->qgroup_ulist);
 477                 fs_info->qgroup_ulist = NULL;
 478                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
 479         }
 480
 481         return ret < 0 ? ret : 0;
 482 }
 483
 484 /*
 485  * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
 486  * first two are in single-threaded paths.And for the third one, we have set
 487  * quota_root to be null with qgroup_lock held before, so it is safe to clean
 488  * up the in-memory structures without qgroup_lock held.
 489  */
 490 void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
 491 {
 492         struct rb_node *n;
 493         struct btrfs_qgroup *qgroup;
 494
 495         while ((n = rb_first(&fs_info->qgroup_tree))) {
 496                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
 497                 rb_erase(n, &fs_info->qgroup_tree);
 498                 __del_qgroup_rb(qgroup);
 499         }
 500         /*
 501          * we call btrfs_free_qgroup_config() when umounting
 502          * filesystem and disabling quota, so we set qgroup_ulit
 503          * to be null here to avoid double free.
 504          */
 505         ulist_free(fs_info->qgroup_ulist);
 506         fs_info->qgroup_ulist = NULL;
 507 }
 508
 509 static int add_qgroup_relation_item(struct btrfs_trans_handle *trans,
 510                                     struct btrfs_root *quota_root,
 511                                     u64 src, u64 dst)
 512 {
 513         int ret;
 514         struct btrfs_path *path;
 515         struct btrfs_key key;
 516
 517         path = btrfs_alloc_path();
 518         if (!path)
 519                 return -ENOMEM;
 520
 521         key.objectid = src;
 522         key.type = BTRFS_QGROUP_RELATION_KEY;
 523         key.offset = dst;
 524
 525         ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
 526
 527         btrfs_mark_buffer_dirty(path->nodes[0]);
 528
 529         btrfs_free_path(path);
 530         return ret;
 531 }
 532
 533 static int del_qgroup_relation_item(struct btrfs_trans_handle *trans,
 534                                     struct btrfs_root *quota_root,
 535                                     u64 src, u64 dst)
 536 {
 537         int ret;
 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_search_slot(trans, quota_root, &key, path, -1, 1);
 550         if (ret < 0)
 551                 goto out;
 552
 553         if (ret > 0) {
 554                 ret = -ENOENT;
 555                 goto out;
 556         }
 557
 558         ret = btrfs_del_item(trans, quota_root, path);
 559 out:
 560         btrfs_free_path(path);
 561         return ret;
 562 }
 563
 564 static int add_qgroup_item(struct btrfs_trans_handle *trans,
 565                            struct btrfs_root *quota_root, u64 qgroupid)
 566 {
 567         int ret;
 568         struct btrfs_path *path;
 569         struct btrfs_qgroup_info_item *qgroup_info;
 570         struct btrfs_qgroup_limit_item *qgroup_limit;
 571         struct extent_buffer *leaf;
 572         struct btrfs_key key;
 573
 574         if (btrfs_test_is_dummy_root(quota_root))
 575                 return 0;
 576
 577         path = btrfs_alloc_path();
 578         if (!path)
 579                 return -ENOMEM;
 580
 581         key.objectid = 0;
 582         key.type = BTRFS_QGROUP_INFO_KEY;
 583         key.offset = qgroupid;
 584
 585         /*
 586          * Avoid a transaction abort by catching -EEXIST here. In that
 587          * case, we proceed by re-initializing the existing structure
 588          * on disk.
 589          */
 590
 591         ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 592                                       sizeof(*qgroup_info));
 593         if (ret && ret != -EEXIST)
 594                 goto out;
 595
 596         leaf = path->nodes[0];
 597         qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
 598                                  struct btrfs_qgroup_info_item);
 599         btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
 600         btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
 601         btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
 602         btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
 603         btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
 604
 605         btrfs_mark_buffer_dirty(leaf);
 606
 607         btrfs_release_path(path);
 608
 609         key.type = BTRFS_QGROUP_LIMIT_KEY;
 610         ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 611                                       sizeof(*qgroup_limit));
 612         if (ret && ret != -EEXIST)
 613                 goto out;
 614
 615         leaf = path->nodes[0];
 616         qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
 617                                   struct btrfs_qgroup_limit_item);
 618         btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
 619         btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
 620         btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
 621         btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
 622         btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
 623
 624         btrfs_mark_buffer_dirty(leaf);
 625
 626         ret = 0;
 627 out:
 628         btrfs_free_path(path);
 629         return ret;
 630 }
 631
 632 static int del_qgroup_item(struct btrfs_trans_handle *trans,
 633                            struct btrfs_root *quota_root, u64 qgroupid)
 634 {
 635         int ret;
 636         struct btrfs_path *path;
 637         struct btrfs_key key;
 638
 639         path = btrfs_alloc_path();
 640         if (!path)
 641                 return -ENOMEM;
 642
 643         key.objectid = 0;
 644         key.type = BTRFS_QGROUP_INFO_KEY;
 645         key.offset = qgroupid;
 646         ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 647         if (ret < 0)
 648                 goto out;
 649
 650         if (ret > 0) {
 651                 ret = -ENOENT;
 652                 goto out;
 653         }
 654
 655         ret = btrfs_del_item(trans, quota_root, path);
 656         if (ret)
 657                 goto out;
 658
 659         btrfs_release_path(path);
 660
 661         key.type = BTRFS_QGROUP_LIMIT_KEY;
 662         ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 663         if (ret < 0)
 664                 goto out;
 665
 666         if (ret > 0) {
 667                 ret = -ENOENT;
 668                 goto out;
 669         }
 670
 671         ret = btrfs_del_item(trans, quota_root, path);
 672
 673 out:
 674         btrfs_free_path(path);
 675         return ret;
 676 }
 677
 678 static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
 679                                     struct btrfs_root *root,
 680                                     struct btrfs_qgroup *qgroup)
 681 {
 682         struct btrfs_path *path;
 683         struct btrfs_key key;
 684         struct extent_buffer *l;
 685         struct btrfs_qgroup_limit_item *qgroup_limit;
 686         int ret;
 687         int slot;
 688
 689         key.objectid = 0;
 690         key.type = BTRFS_QGROUP_LIMIT_KEY;
 691         key.offset = qgroup->qgroupid;
 692
 693         path = btrfs_alloc_path();
 694         if (!path)
 695                 return -ENOMEM;
 696
 697         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 698         if (ret > 0)
 699                 ret = -ENOENT;
 700
 701         if (ret)
 702                 goto out;
 703
 704         l = path->nodes[0];
 705         slot = path->slots[0];
 706         qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
 707         btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
 708         btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
 709         btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
 710         btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
 711         btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
 712
 713         btrfs_mark_buffer_dirty(l);
 714
 715 out:
 716         btrfs_free_path(path);
 717         return ret;
 718 }
 719
 720 static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
 721                                    struct btrfs_root *root,
 722                                    struct btrfs_qgroup *qgroup)
 723 {
 724         struct btrfs_path *path;
 725         struct btrfs_key key;
 726         struct extent_buffer *l;
 727         struct btrfs_qgroup_info_item *qgroup_info;
 728         int ret;
 729         int slot;
 730
 731         if (btrfs_test_is_dummy_root(root))
 732                 return 0;
 733
 734         key.objectid = 0;
 735         key.type = BTRFS_QGROUP_INFO_KEY;
 736         key.offset = qgroup->qgroupid;
 737
 738         path = btrfs_alloc_path();
 739         if (!path)
 740                 return -ENOMEM;
 741
 742         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 743         if (ret > 0)
 744                 ret = -ENOENT;
 745
 746         if (ret)
 747                 goto out;
 748
 749         l = path->nodes[0];
 750         slot = path->slots[0];
 751         qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 752         btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 753         btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 754         btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 755         btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 756         btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 757
 758         btrfs_mark_buffer_dirty(l);
 759
 760 out:
 761         btrfs_free_path(path);
 762         return ret;
 763 }
 764
 765 static int update_qgroup_status_item(struct btrfs_trans_handle *trans,
 766                                      struct btrfs_fs_info *fs_info,
 767                                     struct btrfs_root *root)
 768 {
 769         struct btrfs_path *path;
 770         struct btrfs_key key;
 771         struct extent_buffer *l;
 772         struct btrfs_qgroup_status_item *ptr;
 773         int ret;
 774         int slot;
 775
 776         key.objectid = 0;
 777         key.type = BTRFS_QGROUP_STATUS_KEY;
 778         key.offset = 0;
 779
 780         path = btrfs_alloc_path();
 781         if (!path)
 782                 return -ENOMEM;
 783
 784         ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 785         if (ret > 0)
 786                 ret = -ENOENT;
 787
 788         if (ret)
 789                 goto out;
 790
 791         l = path->nodes[0];
 792         slot = path->slots[0];
 793         ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 794         btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
 795         btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 796         btrfs_set_qgroup_status_rescan(l, ptr,
 797                                 fs_info->qgroup_rescan_progress.objectid);
 798
 799         btrfs_mark_buffer_dirty(l);
 800
 801 out:
 802         btrfs_free_path(path);
 803         return ret;
 804 }
 805
 806 /*
 807  * called with qgroup_lock held
 808  */
 809 static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 810                                   struct btrfs_root *root)
 811 {
 812         struct btrfs_path *path;
 813         struct btrfs_key key;
 814         struct extent_buffer *leaf = NULL;
 815         int ret;
 816         int nr = 0;
 817
 818         path = btrfs_alloc_path();
 819         if (!path)
 820                 return -ENOMEM;
 821
 822         path->leave_spinning = 1;
 823
 824         key.objectid = 0;
 825         key.offset = 0;
 826         key.type = 0;
 827
 828         while (1) {
 829                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 830                 if (ret < 0)
 831                         goto out;
 832                 leaf = path->nodes[0];
 833                 nr = btrfs_header_nritems(leaf);
 834                 if (!nr)
 835                         break;
 836                 /*
 837                  * delete the leaf one by one
 838                  * since the whole tree is going
 839                  * to be deleted.
 840                  */
 841                 path->slots[0] = 0;
 842                 ret = btrfs_del_items(trans, root, path, 0, nr);
 843                 if (ret)
 844                         goto out;
 845
 846                 btrfs_release_path(path);
 847         }
 848         ret = 0;
 849 out:
 850         root->fs_info->pending_quota_state = 0;
 851         btrfs_free_path(path);
 852         return ret;
 853 }
 854
 855 int btrfs_quota_enable(struct btrfs_trans_handle *trans,
 856                        struct btrfs_fs_info *fs_info)
 857 {
 858         struct btrfs_root *quota_root;
 859         struct btrfs_root *tree_root = fs_info->tree_root;
 860         struct btrfs_path *path = NULL;
 861         struct btrfs_qgroup_status_item *ptr;
 862         struct extent_buffer *leaf;
 863         struct btrfs_key key;
 864         struct btrfs_key found_key;
 865         struct btrfs_qgroup *qgroup = NULL;
 866         int ret = 0;
 867         int slot;
 868
 869         mutex_lock(&fs_info->qgroup_ioctl_lock);
 870         if (fs_info->quota_root) {
 871                 fs_info->pending_quota_state = 1;
 872                 goto out;
 873         }
 874
 875         fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
 876         if (!fs_info->qgroup_ulist) {
 877                 ret = -ENOMEM;
 878                 goto out;
 879         }
 880
 881         /*
 882          * initially create the quota tree
 883          */
 884         quota_root = btrfs_create_tree(trans, fs_info,
 885                                        BTRFS_QUOTA_TREE_OBJECTID);
 886         if (IS_ERR(quota_root)) {
 887                 ret =  PTR_ERR(quota_root);
 888                 goto out;
 889         }
 890
 891         path = btrfs_alloc_path();
 892         if (!path) {
 893                 ret = -ENOMEM;
 894                 goto out_free_root;
 895         }
 896
 897         key.objectid = 0;
 898         key.type = BTRFS_QGROUP_STATUS_KEY;
 899         key.offset = 0;
 900
 901         ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 902                                       sizeof(*ptr));
 903         if (ret)
 904                 goto out_free_path;
 905
 906         leaf = path->nodes[0];
 907         ptr = btrfs_item_ptr(leaf, path->slots[0],
 908                                  struct btrfs_qgroup_status_item);
 909         btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
 910         btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
 911         fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
 912                                 BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 913         btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
 914         btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
 915
 916         btrfs_mark_buffer_dirty(leaf);
 917
 918         key.objectid = 0;
 919         key.type = BTRFS_ROOT_REF_KEY;
 920         key.offset = 0;
 921
 922         btrfs_release_path(path);
 923         ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
 924         if (ret > 0)
 925                 goto out_add_root;
 926         if (ret < 0)
 927                 goto out_free_path;
 928
 929
 930         while (1) {
 931                 slot = path->slots[0];
 932                 leaf = path->nodes[0];
 933                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
 934
 935                 if (found_key.type == BTRFS_ROOT_REF_KEY) {
 936                         ret = add_qgroup_item(trans, quota_root,
 937                                               found_key.offset);
 938                         if (ret)
 939                                 goto out_free_path;
 940
 941                         qgroup = add_qgroup_rb(fs_info, found_key.offset);
 942                         if (IS_ERR(qgroup)) {
 943                                 ret = PTR_ERR(qgroup);
 944                                 goto out_free_path;
 945                         }
 946                 }
 947                 ret = btrfs_next_item(tree_root, path);
 948                 if (ret < 0)
 949                         goto out_free_path;
 950                 if (ret)
 951                         break;
 952         }
 953
 954 out_add_root:
 955         btrfs_release_path(path);
 956         ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
 957         if (ret)
 958                 goto out_free_path;
 959
 960         qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
 961         if (IS_ERR(qgroup)) {
 962                 ret = PTR_ERR(qgroup);
 963                 goto out_free_path;
 964         }
 965         spin_lock(&fs_info->qgroup_lock);
 966         fs_info->quota_root = quota_root;
 967         fs_info->pending_quota_state = 1;
 968         spin_unlock(&fs_info->qgroup_lock);
 969 out_free_path:
 970         btrfs_free_path(path);
 971 out_free_root:
 972         if (ret) {
 973                 free_extent_buffer(quota_root->node);
 974                 free_extent_buffer(quota_root->commit_root);
 975                 kfree(quota_root);
 976         }
 977 out:
 978         if (ret) {
 979                 ulist_free(fs_info->qgroup_ulist);
 980                 fs_info->qgroup_ulist = NULL;
 981         }
 982         mutex_unlock(&fs_info->qgroup_ioctl_lock);
 983         return ret;
 984 }
 985
 986 int btrfs_quota_disable(struct btrfs_trans_handle *trans,
 987                         struct btrfs_fs_info *fs_info)
 988 {
 989         struct btrfs_root *tree_root = fs_info->tree_root;
 990         struct btrfs_root *quota_root;
 991         int ret = 0;
 992
 993         mutex_lock(&fs_info->qgroup_ioctl_lock);
 994         if (!fs_info->quota_root)
 995                 goto out;
 996         spin_lock(&fs_info->qgroup_lock);
 997         fs_info->quota_enabled = 0;
 998         fs_info->pending_quota_state = 0;
 999         quota_root = fs_info->quota_root;
1000         fs_info->quota_root = NULL;
1001         fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1002         spin_unlock(&fs_info->qgroup_lock);
1003
1004         btrfs_free_qgroup_config(fs_info);
1005
1006         ret = btrfs_clean_quota_tree(trans, quota_root);
1007         if (ret)
1008                 goto out;
1009
1010         ret = btrfs_del_root(trans, tree_root, &quota_root->root_key);
1011         if (ret)
1012                 goto out;
1013
1014         list_del(&quota_root->dirty_list);
1015
1016         btrfs_tree_lock(quota_root->node);
1017         clean_tree_block(trans, tree_root->fs_info, quota_root->node);
1018         btrfs_tree_unlock(quota_root->node);
1019         btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
1020
1021         free_extent_buffer(quota_root->node);
1022         free_extent_buffer(quota_root->commit_root);
1023         kfree(quota_root);
1024 out:
1025         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1026         return ret;
1027 }
1028
1029 static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1030                          struct btrfs_qgroup *qgroup)
1031 {
1032         if (list_empty(&qgroup->dirty))
1033                 list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1034 }
1035
1036 /*
1037  * The easy accounting, if we are adding/removing the only ref for an extent
1038  * then this qgroup and all of the parent qgroups get their refrence and
1039  * exclusive counts adjusted.
1040  *
1041  * Caller should hold fs_info->qgroup_lock.
1042  */
1043 static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1044                                     struct ulist *tmp, u64 ref_root,
1045                                     u64 num_bytes, int sign)
1046 {
1047         struct btrfs_qgroup *qgroup;
1048         struct btrfs_qgroup_list *glist;
1049         struct ulist_node *unode;
1050         struct ulist_iterator uiter;
1051         int ret = 0;
1052
1053         qgroup = find_qgroup_rb(fs_info, ref_root);
1054         if (!qgroup)
1055                 goto out;
1056
1057         qgroup->rfer += sign * num_bytes;
1058         qgroup->rfer_cmpr += sign * num_bytes;
1059
1060         WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1061         qgroup->excl += sign * num_bytes;
1062         qgroup->excl_cmpr += sign * num_bytes;
1063         if (sign > 0)
1064                 qgroup->reserved -= num_bytes;
1065
1066         qgroup_dirty(fs_info, qgroup);
1067
1068         /* Get all of the parent groups that contain this qgroup */
1069         list_for_each_entry(glist, &qgroup->groups, next_group) {
1070                 ret = ulist_add(tmp, glist->group->qgroupid,
1071                                 ptr_to_u64(glist->group), GFP_ATOMIC);
1072                 if (ret < 0)
1073                         goto out;
1074         }
1075
1076         /* Iterate all of the parents and adjust their reference counts */
1077         ULIST_ITER_INIT(&uiter);
1078         while ((unode = ulist_next(tmp, &uiter))) {
1079                 qgroup = u64_to_ptr(unode->aux);
1080                 qgroup->rfer += sign * num_bytes;
1081                 qgroup->rfer_cmpr += sign * num_bytes;
1082                 WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1083                 qgroup->excl += sign * num_bytes;
1084                 if (sign > 0)
1085                         qgroup->reserved -= num_bytes;
1086                 qgroup->excl_cmpr += sign * num_bytes;
1087                 qgroup_dirty(fs_info, qgroup);
1088
1089                 /* Add any parents of the parents */
1090                 list_for_each_entry(glist, &qgroup->groups, next_group) {
1091                         ret = ulist_add(tmp, glist->group->qgroupid,
1092                                         ptr_to_u64(glist->group), GFP_ATOMIC);
1093                         if (ret < 0)
1094                                 goto out;
1095                 }
1096         }
1097         ret = 0;
1098 out:
1099         return ret;
1100 }
1101
1102
1103 /*
1104  * Quick path for updating qgroup with only excl refs.
1105  *
1106  * In that case, just update all parent will be enough.
1107  * Or we needs to do a full rescan.
1108  * Caller should also hold fs_info->qgroup_lock.
1109  *
1110  * Return 0 for quick update, return >0 for need to full rescan
1111  * and mark INCONSISTENT flag.
1112  * Return < 0 for other error.
1113  */
1114 static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1115                                    struct ulist *tmp, u64 src, u64 dst,
1116                                    int sign)
1117 {
1118         struct btrfs_qgroup *qgroup;
1119         int ret = 1;
1120         int err = 0;
1121
1122         qgroup = find_qgroup_rb(fs_info, src);
1123         if (!qgroup)
1124                 goto out;
1125         if (qgroup->excl == qgroup->rfer) {
1126                 ret = 0;
1127                 err = __qgroup_excl_accounting(fs_info, tmp, dst,
1128                                                qgroup->excl, sign);
1129                 if (err < 0) {
1130                         ret = err;
1131                         goto out;
1132                 }
1133         }
1134 out:
1135         if (ret)
1136                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1137         return ret;
1138 }
1139
1140 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
1141                               struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1142 {
1143         struct btrfs_root *quota_root;
1144         struct btrfs_qgroup *parent;
1145         struct btrfs_qgroup *member;
1146         struct btrfs_qgroup_list *list;
1147         struct ulist *tmp;
1148         int ret = 0;
1149
1150         /* Check the level of src and dst first */
1151         if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1152                 return -EINVAL;
1153
1154         tmp = ulist_alloc(GFP_NOFS);
1155         if (!tmp)
1156                 return -ENOMEM;
1157
1158         mutex_lock(&fs_info->qgroup_ioctl_lock);
1159         quota_root = fs_info->quota_root;
1160         if (!quota_root) {
1161                 ret = -EINVAL;
1162                 goto out;
1163         }
1164         member = find_qgroup_rb(fs_info, src);
1165         parent = find_qgroup_rb(fs_info, dst);
1166         if (!member || !parent) {
1167                 ret = -EINVAL;
1168                 goto out;
1169         }
1170
1171         /* check if such qgroup relation exist firstly */
1172         list_for_each_entry(list, &member->groups, next_group) {
1173                 if (list->group == parent) {
1174                         ret = -EEXIST;
1175                         goto out;
1176                 }
1177         }
1178
1179         ret = add_qgroup_relation_item(trans, quota_root, src, dst);
1180         if (ret)
1181                 goto out;
1182
1183         ret = add_qgroup_relation_item(trans, quota_root, dst, src);
1184         if (ret) {
1185                 del_qgroup_relation_item(trans, quota_root, src, dst);
1186                 goto out;
1187         }
1188
1189         spin_lock(&fs_info->qgroup_lock);
1190         ret = add_relation_rb(quota_root->fs_info, src, dst);
1191         if (ret < 0) {
1192                 spin_unlock(&fs_info->qgroup_lock);
1193                 goto out;
1194         }
1195         ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1196         spin_unlock(&fs_info->qgroup_lock);
1197 out:
1198         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1199         ulist_free(tmp);
1200         return ret;
1201 }
1202
1203 int __del_qgroup_relation(struct btrfs_trans_handle *trans,
1204                               struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1205 {
1206         struct btrfs_root *quota_root;
1207         struct btrfs_qgroup *parent;
1208         struct btrfs_qgroup *member;
1209         struct btrfs_qgroup_list *list;
1210         struct ulist *tmp;
1211         int ret = 0;
1212         int err;
1213
1214         tmp = ulist_alloc(GFP_NOFS);
1215         if (!tmp)
1216                 return -ENOMEM;
1217
1218         quota_root = fs_info->quota_root;
1219         if (!quota_root) {
1220                 ret = -EINVAL;
1221                 goto out;
1222         }
1223
1224         member = find_qgroup_rb(fs_info, src);
1225         parent = find_qgroup_rb(fs_info, dst);
1226         if (!member || !parent) {
1227                 ret = -EINVAL;
1228                 goto out;
1229         }
1230
1231         /* check if such qgroup relation exist firstly */
1232         list_for_each_entry(list, &member->groups, next_group) {
1233                 if (list->group == parent)
1234                         goto exist;
1235         }
1236         ret = -ENOENT;
1237         goto out;
1238 exist:
1239         ret = del_qgroup_relation_item(trans, quota_root, src, dst);
1240         err = del_qgroup_relation_item(trans, quota_root, dst, src);
1241         if (err && !ret)
1242                 ret = err;
1243
1244         spin_lock(&fs_info->qgroup_lock);
1245         del_relation_rb(fs_info, src, dst);
1246         ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1247         spin_unlock(&fs_info->qgroup_lock);
1248 out:
1249         ulist_free(tmp);
1250         return ret;
1251 }
1252
1253 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
1254                               struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1255 {
1256         int ret = 0;
1257
1258         mutex_lock(&fs_info->qgroup_ioctl_lock);
1259         ret = __del_qgroup_relation(trans, fs_info, src, dst);
1260         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1261
1262         return ret;
1263 }
1264
1265 int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
1266                         struct btrfs_fs_info *fs_info, u64 qgroupid)
1267 {
1268         struct btrfs_root *quota_root;
1269         struct btrfs_qgroup *qgroup;
1270         int ret = 0;
1271
1272         mutex_lock(&fs_info->qgroup_ioctl_lock);
1273         quota_root = fs_info->quota_root;
1274         if (!quota_root) {
1275                 ret = -EINVAL;
1276                 goto out;
1277         }
1278         qgroup = find_qgroup_rb(fs_info, qgroupid);
1279         if (qgroup) {
1280                 ret = -EEXIST;
1281                 goto out;
1282         }
1283
1284         ret = add_qgroup_item(trans, quota_root, qgroupid);
1285         if (ret)
1286                 goto out;
1287
1288         spin_lock(&fs_info->qgroup_lock);
1289         qgroup = add_qgroup_rb(fs_info, qgroupid);
1290         spin_unlock(&fs_info->qgroup_lock);
1291
1292         if (IS_ERR(qgroup))
1293                 ret = PTR_ERR(qgroup);
1294 out:
1295         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1296         return ret;
1297 }
1298
1299 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
1300                         struct btrfs_fs_info *fs_info, u64 qgroupid)
1301 {
1302         struct btrfs_root *quota_root;
1303         struct btrfs_qgroup *qgroup;
1304         struct btrfs_qgroup_list *list;
1305         int ret = 0;
1306
1307         mutex_lock(&fs_info->qgroup_ioctl_lock);
1308         quota_root = fs_info->quota_root;
1309         if (!quota_root) {
1310                 ret = -EINVAL;
1311                 goto out;
1312         }
1313
1314         qgroup = find_qgroup_rb(fs_info, qgroupid);
1315         if (!qgroup) {
1316                 ret = -ENOENT;
1317                 goto out;
1318         } else {
1319                 /* check if there are no children of this qgroup */
1320                 if (!list_empty(&qgroup->members)) {
1321                         ret = -EBUSY;
1322                         goto out;
1323                 }
1324         }
1325         ret = del_qgroup_item(trans, quota_root, qgroupid);
1326
1327         while (!list_empty(&qgroup->groups)) {
1328                 list = list_first_entry(&qgroup->groups,
1329                                         struct btrfs_qgroup_list, next_group);
1330                 ret = __del_qgroup_relation(trans, fs_info,
1331                                            qgroupid,
1332                                            list->group->qgroupid);
1333                 if (ret)
1334                         goto out;
1335         }
1336
1337         spin_lock(&fs_info->qgroup_lock);
1338         del_qgroup_rb(quota_root->fs_info, qgroupid);
1339         spin_unlock(&fs_info->qgroup_lock);
1340 out:
1341         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1342         return ret;
1343 }
1344
1345 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans,
1346                        struct btrfs_fs_info *fs_info, u64 qgroupid,
1347                        struct btrfs_qgroup_limit *limit)
1348 {
1349         struct btrfs_root *quota_root;
1350         struct btrfs_qgroup *qgroup;
1351         int ret = 0;
1352         /* Sometimes we would want to clear the limit on this qgroup.
1353          * To meet this requirement, we treat the -1 as a special value
1354          * which tell kernel to clear the limit on this qgroup.
1355          */
1356         const u64 CLEAR_VALUE = -1;
1357
1358         mutex_lock(&fs_info->qgroup_ioctl_lock);
1359         quota_root = fs_info->quota_root;
1360         if (!quota_root) {
1361                 ret = -EINVAL;
1362                 goto out;
1363         }
1364
1365         qgroup = find_qgroup_rb(fs_info, qgroupid);
1366         if (!qgroup) {
1367                 ret = -ENOENT;
1368                 goto out;
1369         }
1370
1371         spin_lock(&fs_info->qgroup_lock);
1372         if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1373                 if (limit->max_rfer == CLEAR_VALUE) {
1374                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1375                         limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1376                         qgroup->max_rfer = 0;
1377                 } else {
1378                         qgroup->max_rfer = limit->max_rfer;
1379                 }
1380         }
1381         if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1382                 if (limit->max_excl == CLEAR_VALUE) {
1383                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1384                         limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1385                         qgroup->max_excl = 0;
1386                 } else {
1387                         qgroup->max_excl = limit->max_excl;
1388                 }
1389         }
1390         if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1391                 if (limit->rsv_rfer == CLEAR_VALUE) {
1392                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1393                         limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1394                         qgroup->rsv_rfer = 0;
1395                 } else {
1396                         qgroup->rsv_rfer = limit->rsv_rfer;
1397                 }
1398         }
1399         if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1400                 if (limit->rsv_excl == CLEAR_VALUE) {
1401                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1402                         limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1403                         qgroup->rsv_excl = 0;
1404                 } else {
1405                         qgroup->rsv_excl = limit->rsv_excl;
1406                 }
1407         }
1408         qgroup->lim_flags |= limit->flags;
1409
1410         spin_unlock(&fs_info->qgroup_lock);
1411
1412         ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1413         if (ret) {
1414                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1415                 btrfs_info(fs_info, "unable to update quota limit for %llu",
1416                        qgroupid);
1417         }
1418
1419 out:
1420         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1421         return ret;
1422 }
1423
1424 int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans,
1425                                          struct btrfs_fs_info *fs_info)
1426 {
1427         struct btrfs_qgroup_extent_record *record;
1428         struct btrfs_delayed_ref_root *delayed_refs;
1429         struct rb_node *node;
1430         u64 qgroup_to_skip;
1431         int ret = 0;
1432
1433         delayed_refs = &trans->transaction->delayed_refs;
1434         qgroup_to_skip = delayed_refs->qgroup_to_skip;
1435
1436         /*
1437          * No need to do lock, since this function will only be called in
1438          * btrfs_commmit_transaction().
1439          */
1440         node = rb_first(&delayed_refs->dirty_extent_root);
1441         while (node) {
1442                 record = rb_entry(node, struct btrfs_qgroup_extent_record,
1443                                   node);
1444                 ret = btrfs_find_all_roots(NULL, fs_info, record->bytenr, 0,
1445                                            &record->old_roots);
1446                 if (ret < 0)
1447                         break;
1448                 if (qgroup_to_skip)
1449                         ulist_del(record->old_roots, qgroup_to_skip, 0);
1450                 node = rb_next(node);
1451         }
1452         return ret;
1453 }
1454
1455 struct btrfs_qgroup_extent_record
1456 *btrfs_qgroup_insert_dirty_extent(struct btrfs_delayed_ref_root *delayed_refs,
1457                                   struct btrfs_qgroup_extent_record *record)
1458 {
1459         struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1460         struct rb_node *parent_node = NULL;
1461         struct btrfs_qgroup_extent_record *entry;
1462         u64 bytenr = record->bytenr;
1463
1464         while (*p) {
1465                 parent_node = *p;
1466                 entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1467                                  node);
1468                 if (bytenr < entry->bytenr)
1469                         p = &(*p)->rb_left;
1470                 else if (bytenr > entry->bytenr)
1471                         p = &(*p)->rb_right;
1472                 else
1473                         return entry;
1474         }
1475
1476         rb_link_node(&record->node, parent_node, p);
1477         rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1478         return NULL;
1479 }
1480
1481 #define UPDATE_NEW      0
1482 #define UPDATE_OLD      1
1483 /*
1484  * Walk all of the roots that points to the bytenr and adjust their refcnts.
1485  */
1486 static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
1487                                 struct ulist *roots, struct ulist *tmp,
1488                                 struct ulist *qgroups, u64 seq, int update_old)
1489 {
1490         struct ulist_node *unode;
1491         struct ulist_iterator uiter;
1492         struct ulist_node *tmp_unode;
1493         struct ulist_iterator tmp_uiter;
1494         struct btrfs_qgroup *qg;
1495         int ret = 0;
1496
1497         if (!roots)
1498                 return 0;
1499         ULIST_ITER_INIT(&uiter);
1500         while ((unode = ulist_next(roots, &uiter))) {
1501                 qg = find_qgroup_rb(fs_info, unode->val);
1502                 if (!qg)
1503                         continue;
1504
1505                 ulist_reinit(tmp);
1506                 ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
1507                                 GFP_ATOMIC);
1508                 if (ret < 0)
1509                         return ret;
1510                 ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg), GFP_ATOMIC);
1511                 if (ret < 0)
1512                         return ret;
1513                 ULIST_ITER_INIT(&tmp_uiter);
1514                 while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
1515                         struct btrfs_qgroup_list *glist;
1516
1517                         qg = u64_to_ptr(tmp_unode->aux);
1518                         if (update_old)
1519                                 btrfs_qgroup_update_old_refcnt(qg, seq, 1);
1520                         else
1521                                 btrfs_qgroup_update_new_refcnt(qg, seq, 1);
1522                         list_for_each_entry(glist, &qg->groups, next_group) {
1523                                 ret = ulist_add(qgroups, glist->group->qgroupid,
1524                                                 ptr_to_u64(glist->group),
1525                                                 GFP_ATOMIC);
1526                                 if (ret < 0)
1527                                         return ret;
1528                                 ret = ulist_add(tmp, glist->group->qgroupid,
1529                                                 ptr_to_u64(glist->group),
1530                                                 GFP_ATOMIC);
1531                                 if (ret < 0)
1532                                         return ret;
1533                         }
1534                 }
1535         }
1536         return 0;
1537 }
1538
1539 /*
1540  * Update qgroup rfer/excl counters.
1541  * Rfer update is easy, codes can explain themselves.
1542  *
1543  * Excl update is tricky, the update is split into 2 part.
1544  * Part 1: Possible exclusive <-> sharing detect:
1545  *      |       A       |       !A      |
1546  *  -------------------------------------
1547  *  B   |       *       |       -       |
1548  *  -------------------------------------
1549  *  !B  |       +       |       **      |
1550  *  -------------------------------------
1551  *
1552  * Conditions:
1553  * A:   cur_old_roots < nr_old_roots    (not exclusive before)
1554  * !A:  cur_old_roots == nr_old_roots   (possible exclusive before)
1555  * B:   cur_new_roots < nr_new_roots    (not exclusive now)
1556  * !B:  cur_new_roots == nr_new_roots   (possible exclsuive now)
1557  *
1558  * Results:
1559  * +: Possible sharing -> exclusive     -: Possible exclusive -> sharing
1560  * *: Definitely not changed.           **: Possible unchanged.
1561  *
1562  * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
1563  *
1564  * To make the logic clear, we first use condition A and B to split
1565  * combination into 4 results.
1566  *
1567  * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
1568  * only on variant maybe 0.
1569  *
1570  * Lastly, check result **, since there are 2 variants maybe 0, split them
1571  * again(2x2).
1572  * But this time we don't need to consider other things, the codes and logic
1573  * is easy to understand now.
1574  */
1575 static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
1576                                   struct ulist *qgroups,
1577                                   u64 nr_old_roots,
1578                                   u64 nr_new_roots,
1579                                   u64 num_bytes, u64 seq)
1580 {
1581         struct ulist_node *unode;
1582         struct ulist_iterator uiter;
1583         struct btrfs_qgroup *qg;
1584         u64 cur_new_count, cur_old_count;
1585
1586         ULIST_ITER_INIT(&uiter);
1587         while ((unode = ulist_next(qgroups, &uiter))) {
1588                 bool dirty = false;
1589
1590                 qg = u64_to_ptr(unode->aux);
1591                 cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
1592                 cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
1593
1594                 /* Rfer update part */
1595                 if (cur_old_count == 0 && cur_new_count > 0) {
1596                         qg->rfer += num_bytes;
1597                         qg->rfer_cmpr += num_bytes;
1598                         dirty = true;
1599                 }
1600                 if (cur_old_count > 0 && cur_new_count == 0) {
1601                         qg->rfer -= num_bytes;
1602                         qg->rfer_cmpr -= num_bytes;
1603                         dirty = true;
1604                 }
1605
1606                 /* Excl update part */
1607                 /* Exclusive/none -> shared case */
1608                 if (cur_old_count == nr_old_roots &&
1609                     cur_new_count < nr_new_roots) {
1610                         /* Exclusive -> shared */
1611                         if (cur_old_count != 0) {
1612                                 qg->excl -= num_bytes;
1613                                 qg->excl_cmpr -= num_bytes;
1614                                 dirty = true;
1615                         }
1616                 }
1617
1618                 /* Shared -> exclusive/none case */
1619                 if (cur_old_count < nr_old_roots &&
1620                     cur_new_count == nr_new_roots) {
1621                         /* Shared->exclusive */
1622                         if (cur_new_count != 0) {
1623                                 qg->excl += num_bytes;
1624                                 qg->excl_cmpr += num_bytes;
1625                                 dirty = true;
1626                         }
1627                 }
1628
1629                 /* Exclusive/none -> exclusive/none case */
1630                 if (cur_old_count == nr_old_roots &&
1631                     cur_new_count == nr_new_roots) {
1632                         if (cur_old_count == 0) {
1633                                 /* None -> exclusive/none */
1634
1635                                 if (cur_new_count != 0) {
1636                                         /* None -> exclusive */
1637                                         qg->excl += num_bytes;
1638                                         qg->excl_cmpr += num_bytes;
1639                                         dirty = true;
1640                                 }
1641                                 /* None -> none, nothing changed */
1642                         } else {
1643                                 /* Exclusive -> exclusive/none */
1644
1645                                 if (cur_new_count == 0) {
1646                                         /* Exclusive -> none */
1647                                         qg->excl -= num_bytes;
1648                                         qg->excl_cmpr -= num_bytes;
1649                                         dirty = true;
1650                                 }
1651                                 /* Exclusive -> exclusive, nothing changed */
1652                         }
1653                 }
1654
1655                 /* For exclusive extent, free its reserved bytes too */
1656                 if (nr_old_roots == 0 && nr_new_roots == 1 &&
1657                     cur_new_count == nr_new_roots)
1658                         qg->reserved -= num_bytes;
1659                 if (dirty)
1660                         qgroup_dirty(fs_info, qg);
1661         }
1662         return 0;
1663 }
1664
1665 int
1666 btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans,
1667                             struct btrfs_fs_info *fs_info,
1668                             u64 bytenr, u64 num_bytes,
1669                             struct ulist *old_roots, struct ulist *new_roots)
1670 {
1671         struct ulist *qgroups = NULL;
1672         struct ulist *tmp = NULL;
1673         u64 seq;
1674         u64 nr_new_roots = 0;
1675         u64 nr_old_roots = 0;
1676         int ret = 0;
1677
1678         if (new_roots)
1679                 nr_new_roots = new_roots->nnodes;
1680         if (old_roots)
1681                 nr_old_roots = old_roots->nnodes;
1682
1683         if (!fs_info->quota_enabled)
1684                 goto out_free;
1685         BUG_ON(!fs_info->quota_root);
1686
1687         qgroups = ulist_alloc(GFP_NOFS);
1688         if (!qgroups) {
1689                 ret = -ENOMEM;
1690                 goto out_free;
1691         }
1692         tmp = ulist_alloc(GFP_NOFS);
1693         if (!tmp) {
1694                 ret = -ENOMEM;
1695                 goto out_free;
1696         }
1697
1698         mutex_lock(&fs_info->qgroup_rescan_lock);
1699         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
1700                 if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
1701                         mutex_unlock(&fs_info->qgroup_rescan_lock);
1702                         ret = 0;
1703                         goto out_free;
1704                 }
1705         }
1706         mutex_unlock(&fs_info->qgroup_rescan_lock);
1707
1708         spin_lock(&fs_info->qgroup_lock);
1709         seq = fs_info->qgroup_seq;
1710
1711         /* Update old refcnts using old_roots */
1712         ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
1713                                    UPDATE_OLD);
1714         if (ret < 0)
1715                 goto out;
1716
1717         /* Update new refcnts using new_roots */
1718         ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
1719                                    UPDATE_NEW);
1720         if (ret < 0)
1721                 goto out;
1722
1723         qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
1724                                num_bytes, seq);
1725
1726         /*
1727          * Bump qgroup_seq to avoid seq overlap
1728          */
1729         fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
1730 out:
1731         spin_unlock(&fs_info->qgroup_lock);
1732 out_free:
1733         ulist_free(tmp);
1734         ulist_free(qgroups);
1735         ulist_free(old_roots);
1736         ulist_free(new_roots);
1737         return ret;
1738 }
1739
1740 int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans,
1741                                  struct btrfs_fs_info *fs_info)
1742 {
1743         struct btrfs_qgroup_extent_record *record;
1744         struct btrfs_delayed_ref_root *delayed_refs;
1745         struct ulist *new_roots = NULL;
1746         struct rb_node *node;
1747         u64 qgroup_to_skip;
1748         int ret = 0;
1749
1750         delayed_refs = &trans->transaction->delayed_refs;
1751         qgroup_to_skip = delayed_refs->qgroup_to_skip;
1752         while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
1753                 record = rb_entry(node, struct btrfs_qgroup_extent_record,
1754                                   node);
1755
1756                 if (!ret) {
1757                         /*
1758                          * Use (u64)-1 as time_seq to do special search, which
1759                          * doesn't lock tree or delayed_refs and search current
1760                          * root. It's safe inside commit_transaction().
1761                          */
1762                         ret = btrfs_find_all_roots(trans, fs_info,
1763                                         record->bytenr, (u64)-1, &new_roots);
1764                         if (ret < 0)
1765                                 goto cleanup;
1766                         if (qgroup_to_skip)
1767                                 ulist_del(new_roots, qgroup_to_skip, 0);
1768                         ret = btrfs_qgroup_account_extent(trans, fs_info,
1769                                         record->bytenr, record->num_bytes,
1770                                         record->old_roots, new_roots);
1771                         record->old_roots = NULL;
1772                         new_roots = NULL;
1773                 }
1774 cleanup:
1775                 ulist_free(record->old_roots);
1776                 ulist_free(new_roots);
1777                 new_roots = NULL;
1778                 rb_erase(node, &delayed_refs->dirty_extent_root);
1779                 kfree(record);
1780
1781         }
1782         return ret;
1783 }
1784
1785 /*
1786  * called from commit_transaction. Writes all changed qgroups to disk.
1787  */
1788 int btrfs_run_qgroups(struct btrfs_trans_handle *trans,
1789                       struct btrfs_fs_info *fs_info)
1790 {
1791         struct btrfs_root *quota_root = fs_info->quota_root;
1792         int ret = 0;
1793         int start_rescan_worker = 0;
1794
1795         if (!quota_root)
1796                 goto out;
1797
1798         if (!fs_info->quota_enabled && fs_info->pending_quota_state)
1799                 start_rescan_worker = 1;
1800
1801         fs_info->quota_enabled = fs_info->pending_quota_state;
1802
1803         spin_lock(&fs_info->qgroup_lock);
1804         while (!list_empty(&fs_info->dirty_qgroups)) {
1805                 struct btrfs_qgroup *qgroup;
1806                 qgroup = list_first_entry(&fs_info->dirty_qgroups,
1807                                           struct btrfs_qgroup, dirty);
1808                 list_del_init(&qgroup->dirty);
1809                 spin_unlock(&fs_info->qgroup_lock);
1810                 ret = update_qgroup_info_item(trans, quota_root, qgroup);
1811                 if (ret)
1812                         fs_info->qgroup_flags |=
1813                                         BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1814                 ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1815                 if (ret)
1816                         fs_info->qgroup_flags |=
1817                                         BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1818                 spin_lock(&fs_info->qgroup_lock);
1819         }
1820         if (fs_info->quota_enabled)
1821                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
1822         else
1823                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1824         spin_unlock(&fs_info->qgroup_lock);
1825
1826         ret = update_qgroup_status_item(trans, fs_info, quota_root);
1827         if (ret)
1828                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1829
1830         if (!ret && start_rescan_worker) {
1831                 ret = qgroup_rescan_init(fs_info, 0, 1);
1832                 if (!ret) {
1833                         qgroup_rescan_zero_tracking(fs_info);
1834                         btrfs_queue_work(fs_info->qgroup_rescan_workers,
1835                                          &fs_info->qgroup_rescan_work);
1836                 }
1837                 ret = 0;
1838         }
1839
1840 out:
1841
1842         return ret;
1843 }
1844
1845 /*
1846  * copy the acounting information between qgroups. This is necessary when a
1847  * snapshot or a subvolume is created
1848  */
1849 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans,
1850                          struct btrfs_fs_info *fs_info, u64 srcid, u64 objectid,
1851                          struct btrfs_qgroup_inherit *inherit)
1852 {
1853         int ret = 0;
1854         int i;
1855         u64 *i_qgroups;
1856         struct btrfs_root *quota_root = fs_info->quota_root;
1857         struct btrfs_qgroup *srcgroup;
1858         struct btrfs_qgroup *dstgroup;
1859         u32 level_size = 0;
1860         u64 nums;
1861
1862         mutex_lock(&fs_info->qgroup_ioctl_lock);
1863         if (!fs_info->quota_enabled)
1864                 goto out;
1865
1866         if (!quota_root) {
1867                 ret = -EINVAL;
1868                 goto out;
1869         }
1870
1871         if (inherit) {
1872                 i_qgroups = (u64 *)(inherit + 1);
1873                 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
1874                        2 * inherit->num_excl_copies;
1875                 for (i = 0; i < nums; ++i) {
1876                         srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
1877                         if (!srcgroup) {
1878                                 ret = -EINVAL;
1879                                 goto out;
1880                         }
1881
1882                         if ((srcgroup->qgroupid >> 48) <= (objectid >> 48)) {
1883                                 ret = -EINVAL;
1884                                 goto out;
1885                         }
1886                         ++i_qgroups;
1887                 }
1888         }
1889
1890         /*
1891          * create a tracking group for the subvol itself
1892          */
1893         ret = add_qgroup_item(trans, quota_root, objectid);
1894         if (ret)
1895                 goto out;
1896
1897         if (srcid) {
1898                 struct btrfs_root *srcroot;
1899                 struct btrfs_key srckey;
1900
1901                 srckey.objectid = srcid;
1902                 srckey.type = BTRFS_ROOT_ITEM_KEY;
1903                 srckey.offset = (u64)-1;
1904                 srcroot = btrfs_read_fs_root_no_name(fs_info, &srckey);
1905                 if (IS_ERR(srcroot)) {
1906                         ret = PTR_ERR(srcroot);
1907                         goto out;
1908                 }
1909
1910                 rcu_read_lock();
1911                 level_size = srcroot->nodesize;
1912                 rcu_read_unlock();
1913         }
1914
1915         /*
1916          * add qgroup to all inherited groups
1917          */
1918         if (inherit) {
1919                 i_qgroups = (u64 *)(inherit + 1);
1920                 for (i = 0; i < inherit->num_qgroups; ++i) {
1921                         ret = add_qgroup_relation_item(trans, quota_root,
1922                                                        objectid, *i_qgroups);
1923                         if (ret)
1924                                 goto out;
1925                         ret = add_qgroup_relation_item(trans, quota_root,
1926                                                        *i_qgroups, objectid);
1927                         if (ret)
1928                                 goto out;
1929                         ++i_qgroups;
1930                 }
1931         }
1932
1933
1934         spin_lock(&fs_info->qgroup_lock);
1935
1936         dstgroup = add_qgroup_rb(fs_info, objectid);
1937         if (IS_ERR(dstgroup)) {
1938                 ret = PTR_ERR(dstgroup);
1939                 goto unlock;
1940         }
1941
1942         if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
1943                 dstgroup->lim_flags = inherit->lim.flags;
1944                 dstgroup->max_rfer = inherit->lim.max_rfer;
1945                 dstgroup->max_excl = inherit->lim.max_excl;
1946                 dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
1947                 dstgroup->rsv_excl = inherit->lim.rsv_excl;
1948
1949                 ret = update_qgroup_limit_item(trans, quota_root, dstgroup);
1950                 if (ret) {
1951                         fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1952                         btrfs_info(fs_info, "unable to update quota limit for %llu",
1953                                dstgroup->qgroupid);
1954                         goto unlock;
1955                 }
1956         }
1957
1958         if (srcid) {
1959                 srcgroup = find_qgroup_rb(fs_info, srcid);
1960                 if (!srcgroup)
1961                         goto unlock;
1962
1963                 /*
1964                  * We call inherit after we clone the root in order to make sure
1965                  * our counts don't go crazy, so at this point the only
1966                  * difference between the two roots should be the root node.
1967                  */
1968                 dstgroup->rfer = srcgroup->rfer;
1969                 dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
1970                 dstgroup->excl = level_size;
1971                 dstgroup->excl_cmpr = level_size;
1972                 srcgroup->excl = level_size;
1973                 srcgroup->excl_cmpr = level_size;
1974
1975                 /* inherit the limit info */
1976                 dstgroup->lim_flags = srcgroup->lim_flags;
1977                 dstgroup->max_rfer = srcgroup->max_rfer;
1978                 dstgroup->max_excl = srcgroup->max_excl;
1979                 dstgroup->rsv_rfer = srcgroup->rsv_rfer;
1980                 dstgroup->rsv_excl = srcgroup->rsv_excl;
1981
1982                 qgroup_dirty(fs_info, dstgroup);
1983                 qgroup_dirty(fs_info, srcgroup);
1984         }
1985
1986         if (!inherit)
1987                 goto unlock;
1988
1989         i_qgroups = (u64 *)(inherit + 1);
1990         for (i = 0; i < inherit->num_qgroups; ++i) {
1991                 ret = add_relation_rb(quota_root->fs_info, objectid,
1992                                       *i_qgroups);
1993                 if (ret)
1994                         goto unlock;
1995                 ++i_qgroups;
1996         }
1997
1998         for (i = 0; i <  inherit->num_ref_copies; ++i) {
1999                 struct btrfs_qgroup *src;
2000                 struct btrfs_qgroup *dst;
2001
2002                 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2003                 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2004
2005                 if (!src || !dst) {
2006                         ret = -EINVAL;
2007                         goto unlock;
2008                 }
2009
2010                 dst->rfer = src->rfer - level_size;
2011                 dst->rfer_cmpr = src->rfer_cmpr - level_size;
2012                 i_qgroups += 2;
2013         }
2014         for (i = 0; i <  inherit->num_excl_copies; ++i) {
2015                 struct btrfs_qgroup *src;
2016                 struct btrfs_qgroup *dst;
2017
2018                 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2019                 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2020
2021                 if (!src || !dst) {
2022                         ret = -EINVAL;
2023                         goto unlock;
2024                 }
2025
2026                 dst->excl = src->excl + level_size;
2027                 dst->excl_cmpr = src->excl_cmpr + level_size;
2028                 i_qgroups += 2;
2029         }
2030
2031 unlock:
2032         spin_unlock(&fs_info->qgroup_lock);
2033 out:
2034         mutex_unlock(&fs_info->qgroup_ioctl_lock);
2035         return ret;
2036 }
2037
2038 int btrfs_qgroup_reserve(struct btrfs_root *root, u64 num_bytes)
2039 {
2040         struct btrfs_root *quota_root;
2041         struct btrfs_qgroup *qgroup;
2042         struct btrfs_fs_info *fs_info = root->fs_info;
2043         u64 ref_root = root->root_key.objectid;
2044         int ret = 0;
2045         struct ulist_node *unode;
2046         struct ulist_iterator uiter;
2047
2048         if (!is_fstree(ref_root))
2049                 return 0;
2050
2051         if (num_bytes == 0)
2052                 return 0;
2053
2054         spin_lock(&fs_info->qgroup_lock);
2055         quota_root = fs_info->quota_root;
2056         if (!quota_root)
2057                 goto out;
2058
2059         qgroup = find_qgroup_rb(fs_info, ref_root);
2060         if (!qgroup)
2061                 goto out;
2062
2063         /*
2064          * in a first step, we check all affected qgroups if any limits would
2065          * be exceeded
2066          */
2067         ulist_reinit(fs_info->qgroup_ulist);
2068         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2069                         (uintptr_t)qgroup, GFP_ATOMIC);
2070         if (ret < 0)
2071                 goto out;
2072         ULIST_ITER_INIT(&uiter);
2073         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2074                 struct btrfs_qgroup *qg;
2075                 struct btrfs_qgroup_list *glist;
2076
2077                 qg = u64_to_ptr(unode->aux);
2078
2079                 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2080                     qg->reserved + (s64)qg->rfer + num_bytes >
2081                     qg->max_rfer) {
2082                         ret = -EDQUOT;
2083                         goto out;
2084                 }
2085
2086                 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2087                     qg->reserved + (s64)qg->excl + num_bytes >
2088                     qg->max_excl) {
2089                         ret = -EDQUOT;
2090                         goto out;
2091                 }
2092
2093                 list_for_each_entry(glist, &qg->groups, next_group) {
2094                         ret = ulist_add(fs_info->qgroup_ulist,
2095                                         glist->group->qgroupid,
2096                                         (uintptr_t)glist->group, GFP_ATOMIC);
2097                         if (ret < 0)
2098                                 goto out;
2099                 }
2100         }
2101         ret = 0;
2102         /*
2103          * no limits exceeded, now record the reservation into all qgroups
2104          */
2105         ULIST_ITER_INIT(&uiter);
2106         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2107                 struct btrfs_qgroup *qg;
2108
2109                 qg = u64_to_ptr(unode->aux);
2110
2111                 qg->reserved += num_bytes;
2112         }
2113
2114 out:
2115         spin_unlock(&fs_info->qgroup_lock);
2116         return ret;
2117 }
2118
2119 void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
2120                                u64 ref_root, u64 num_bytes)
2121 {
2122         struct btrfs_root *quota_root;
2123         struct btrfs_qgroup *qgroup;
2124         struct ulist_node *unode;
2125         struct ulist_iterator uiter;
2126         int ret = 0;
2127
2128         if (!is_fstree(ref_root))
2129                 return;
2130
2131         if (num_bytes == 0)
2132                 return;
2133
2134         spin_lock(&fs_info->qgroup_lock);
2135
2136         quota_root = fs_info->quota_root;
2137         if (!quota_root)
2138                 goto out;
2139
2140         qgroup = find_qgroup_rb(fs_info, ref_root);
2141         if (!qgroup)
2142                 goto out;
2143
2144         ulist_reinit(fs_info->qgroup_ulist);
2145         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2146                         (uintptr_t)qgroup, GFP_ATOMIC);
2147         if (ret < 0)
2148                 goto out;
2149         ULIST_ITER_INIT(&uiter);
2150         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2151                 struct btrfs_qgroup *qg;
2152                 struct btrfs_qgroup_list *glist;
2153
2154                 qg = u64_to_ptr(unode->aux);
2155
2156                 qg->reserved -= num_bytes;
2157
2158                 list_for_each_entry(glist, &qg->groups, next_group) {
2159                         ret = ulist_add(fs_info->qgroup_ulist,
2160                                         glist->group->qgroupid,
2161                                         (uintptr_t)glist->group, GFP_ATOMIC);
2162                         if (ret < 0)
2163                                 goto out;
2164                 }
2165         }
2166
2167 out:
2168         spin_unlock(&fs_info->qgroup_lock);
2169 }
2170
2171 void assert_qgroups_uptodate(struct btrfs_trans_handle *trans)
2172 {
2173         if (list_empty(&trans->qgroup_ref_list) && !trans->delayed_ref_elem.seq)
2174                 return;
2175         btrfs_err(trans->root->fs_info,
2176                 "qgroups not uptodate in trans handle %p:  list is%s empty, "
2177                 "seq is %#x.%x",
2178                 trans, list_empty(&trans->qgroup_ref_list) ? "" : " not",
2179                 (u32)(trans->delayed_ref_elem.seq >> 32),
2180                 (u32)trans->delayed_ref_elem.seq);
2181         BUG();
2182 }
2183
2184 /*
2185  * returns < 0 on error, 0 when more leafs are to be scanned.
2186  * returns 1 when done.
2187  */
2188 static int
2189 qgroup_rescan_leaf(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
2190                    struct btrfs_trans_handle *trans,
2191                    struct extent_buffer *scratch_leaf)
2192 {
2193         struct btrfs_key found;
2194         struct ulist *roots = NULL;
2195         struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
2196         u64 num_bytes;
2197         int slot;
2198         int ret;
2199
2200         path->leave_spinning = 1;
2201         mutex_lock(&fs_info->qgroup_rescan_lock);
2202         ret = btrfs_search_slot_for_read(fs_info->extent_root,
2203                                          &fs_info->qgroup_rescan_progress,
2204                                          path, 1, 0);
2205
2206         pr_debug("current progress key (%llu %u %llu), search_slot ret %d\n",
2207                  fs_info->qgroup_rescan_progress.objectid,
2208                  fs_info->qgroup_rescan_progress.type,
2209                  fs_info->qgroup_rescan_progress.offset, ret);
2210
2211         if (ret) {
2212                 /*
2213                  * The rescan is about to end, we will not be scanning any
2214                  * further blocks. We cannot unset the RESCAN flag here, because
2215                  * we want to commit the transaction if everything went well.
2216                  * To make the live accounting work in this phase, we set our
2217                  * scan progress pointer such that every real extent objectid
2218                  * will be smaller.
2219                  */
2220                 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
2221                 btrfs_release_path(path);
2222                 mutex_unlock(&fs_info->qgroup_rescan_lock);
2223                 return ret;
2224         }
2225
2226         btrfs_item_key_to_cpu(path->nodes[0], &found,
2227                               btrfs_header_nritems(path->nodes[0]) - 1);
2228         fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
2229
2230         btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2231         memcpy(scratch_leaf, path->nodes[0], sizeof(*scratch_leaf));
2232         slot = path->slots[0];
2233         btrfs_release_path(path);
2234         mutex_unlock(&fs_info->qgroup_rescan_lock);
2235
2236         for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
2237                 btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
2238                 if (found.type != BTRFS_EXTENT_ITEM_KEY &&
2239                     found.type != BTRFS_METADATA_ITEM_KEY)
2240                         continue;
2241                 if (found.type == BTRFS_METADATA_ITEM_KEY)
2242                         num_bytes = fs_info->extent_root->nodesize;
2243                 else
2244                         num_bytes = found.offset;
2245
2246                 ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
2247                                            &roots);
2248                 if (ret < 0)
2249                         goto out;
2250                 /* For rescan, just pass old_roots as NULL */
2251                 ret = btrfs_qgroup_account_extent(trans, fs_info,
2252                                 found.objectid, num_bytes, NULL, roots);
2253                 if (ret < 0)
2254                         goto out;
2255         }
2256 out:
2257         btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2258
2259         return ret;
2260 }
2261
2262 static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
2263 {
2264         struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
2265                                                      qgroup_rescan_work);
2266         struct btrfs_path *path;
2267         struct btrfs_trans_handle *trans = NULL;
2268         struct extent_buffer *scratch_leaf = NULL;
2269         int err = -ENOMEM;
2270         int ret = 0;
2271
2272         path = btrfs_alloc_path();
2273         if (!path)
2274                 goto out;
2275         scratch_leaf = kmalloc(sizeof(*scratch_leaf), GFP_NOFS);
2276         if (!scratch_leaf)
2277                 goto out;
2278
2279         err = 0;
2280         while (!err) {
2281                 trans = btrfs_start_transaction(fs_info->fs_root, 0);
2282                 if (IS_ERR(trans)) {
2283                         err = PTR_ERR(trans);
2284                         break;
2285                 }
2286                 if (!fs_info->quota_enabled) {
2287                         err = -EINTR;
2288                 } else {
2289                         err = qgroup_rescan_leaf(fs_info, path, trans,
2290                                                  scratch_leaf);
2291                 }
2292                 if (err > 0)
2293                         btrfs_commit_transaction(trans, fs_info->fs_root);
2294                 else
2295                         btrfs_end_transaction(trans, fs_info->fs_root);
2296         }
2297
2298 out:
2299         kfree(scratch_leaf);
2300         btrfs_free_path(path);
2301
2302         mutex_lock(&fs_info->qgroup_rescan_lock);
2303         fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2304
2305         if (err > 0 &&
2306             fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
2307                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2308         } else if (err < 0) {
2309                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2310         }
2311         mutex_unlock(&fs_info->qgroup_rescan_lock);
2312
2313         /*
2314          * only update status, since the previous part has alreay updated the
2315          * qgroup info.
2316          */
2317         trans = btrfs_start_transaction(fs_info->quota_root, 1);
2318         if (IS_ERR(trans)) {
2319                 err = PTR_ERR(trans);
2320                 btrfs_err(fs_info,
2321                           "fail to start transaction for status update: %d\n",
2322                           err);
2323                 goto done;
2324         }
2325         ret = update_qgroup_status_item(trans, fs_info, fs_info->quota_root);
2326         if (ret < 0) {
2327                 err = ret;
2328                 btrfs_err(fs_info, "fail to update qgroup status: %d\n", err);
2329         }
2330         btrfs_end_transaction(trans, fs_info->quota_root);
2331
2332         if (err >= 0) {
2333                 btrfs_info(fs_info, "qgroup scan completed%s",
2334                         err > 0 ? " (inconsistency flag cleared)" : "");
2335         } else {
2336                 btrfs_err(fs_info, "qgroup scan failed with %d", err);
2337         }
2338
2339 done:
2340         complete_all(&fs_info->qgroup_rescan_completion);
2341 }
2342
2343 /*
2344  * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
2345  * memory required for the rescan context.
2346  */
2347 static int
2348 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
2349                    int init_flags)
2350 {
2351         int ret = 0;
2352
2353         if (!init_flags &&
2354             (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ||
2355              !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))) {
2356                 ret = -EINVAL;
2357                 goto err;
2358         }
2359
2360         mutex_lock(&fs_info->qgroup_rescan_lock);
2361         spin_lock(&fs_info->qgroup_lock);
2362
2363         if (init_flags) {
2364                 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
2365                         ret = -EINPROGRESS;
2366                 else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
2367                         ret = -EINVAL;
2368
2369                 if (ret) {
2370                         spin_unlock(&fs_info->qgroup_lock);
2371                         mutex_unlock(&fs_info->qgroup_rescan_lock);
2372                         goto err;
2373                 }
2374                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2375         }
2376
2377         memset(&fs_info->qgroup_rescan_progress, 0,
2378                 sizeof(fs_info->qgroup_rescan_progress));
2379         fs_info->qgroup_rescan_progress.objectid = progress_objectid;
2380
2381         spin_unlock(&fs_info->qgroup_lock);
2382         mutex_unlock(&fs_info->qgroup_rescan_lock);
2383
2384         init_completion(&fs_info->qgroup_rescan_completion);
2385
2386         memset(&fs_info->qgroup_rescan_work, 0,
2387                sizeof(fs_info->qgroup_rescan_work));
2388         btrfs_init_work(&fs_info->qgroup_rescan_work,
2389                         btrfs_qgroup_rescan_helper,
2390                         btrfs_qgroup_rescan_worker, NULL, NULL);
2391
2392         if (ret) {
2393 err:
2394                 btrfs_info(fs_info, "qgroup_rescan_init failed with %d", ret);
2395                 return ret;
2396         }
2397
2398         return 0;
2399 }
2400
2401 static void
2402 qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
2403 {
2404         struct rb_node *n;
2405         struct btrfs_qgroup *qgroup;
2406
2407         spin_lock(&fs_info->qgroup_lock);
2408         /* clear all current qgroup tracking information */
2409         for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
2410                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
2411                 qgroup->rfer = 0;
2412                 qgroup->rfer_cmpr = 0;
2413                 qgroup->excl = 0;
2414                 qgroup->excl_cmpr = 0;
2415         }
2416         spin_unlock(&fs_info->qgroup_lock);
2417 }
2418
2419 int
2420 btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
2421 {
2422         int ret = 0;
2423         struct btrfs_trans_handle *trans;
2424
2425         ret = qgroup_rescan_init(fs_info, 0, 1);
2426         if (ret)
2427                 return ret;
2428
2429         /*
2430          * We have set the rescan_progress to 0, which means no more
2431          * delayed refs will be accounted by btrfs_qgroup_account_ref.
2432          * However, btrfs_qgroup_account_ref may be right after its call
2433          * to btrfs_find_all_roots, in which case it would still do the
2434          * accounting.
2435          * To solve this, we're committing the transaction, which will
2436          * ensure we run all delayed refs and only after that, we are
2437          * going to clear all tracking information for a clean start.
2438          */
2439
2440         trans = btrfs_join_transaction(fs_info->fs_root);
2441         if (IS_ERR(trans)) {
2442                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2443                 return PTR_ERR(trans);
2444         }
2445         ret = btrfs_commit_transaction(trans, fs_info->fs_root);
2446         if (ret) {
2447                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2448                 return ret;
2449         }
2450
2451         qgroup_rescan_zero_tracking(fs_info);
2452
2453         btrfs_queue_work(fs_info->qgroup_rescan_workers,
2454                          &fs_info->qgroup_rescan_work);
2455
2456         return 0;
2457 }
2458
2459 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info)
2460 {
2461         int running;
2462         int ret = 0;
2463
2464         mutex_lock(&fs_info->qgroup_rescan_lock);
2465         spin_lock(&fs_info->qgroup_lock);
2466         running = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2467         spin_unlock(&fs_info->qgroup_lock);
2468         mutex_unlock(&fs_info->qgroup_rescan_lock);
2469
2470         if (running)
2471                 ret = wait_for_completion_interruptible(
2472                                         &fs_info->qgroup_rescan_completion);
2473
2474         return ret;
2475 }
2476
2477 /*
2478  * this is only called from open_ctree where we're still single threaded, thus
2479  * locking is omitted here.
2480  */
2481 void
2482 btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
2483 {
2484         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
2485                 btrfs_queue_work(fs_info->qgroup_rescan_workers,
2486                                  &fs_info->qgroup_rescan_work);
2487 }
2488
2489 /*
2490  * Reserve qgroup space for range [start, start + len).
2491  *
2492  * This function will either reserve space from related qgroups or doing
2493  * nothing if the range is already reserved.
2494  *
2495  * Return 0 for successful reserve
2496  * Return <0 for error (including -EQUOT)
2497  *
2498  * NOTE: this function may sleep for memory allocation.
2499  */
2500 int btrfs_qgroup_reserve_data(struct inode *inode, u64 start, u64 len)
2501 {
2502         struct btrfs_root *root = BTRFS_I(inode)->root;
2503         struct extent_changeset changeset;
2504         struct ulist_node *unode;
2505         struct ulist_iterator uiter;
2506         int ret;
2507
2508         if (!root->fs_info->quota_enabled || !is_fstree(root->objectid) ||
2509             len == 0)
2510                 return 0;
2511
2512         changeset.bytes_changed = 0;
2513         changeset.range_changed = ulist_alloc(GFP_NOFS);
2514
2515         ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
2516                         start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS,
2517                         &changeset);
2518         if (ret < 0)
2519                 goto cleanup;
2520         ret = btrfs_qgroup_reserve(root, changeset.bytes_changed);
2521         if (ret < 0)
2522                 goto cleanup;
2523
2524         ulist_free(changeset.range_changed);
2525         return ret;
2526
2527 cleanup:
2528         /* cleanup already reserved ranges */
2529         ULIST_ITER_INIT(&uiter);
2530         while ((unode = ulist_next(changeset.range_changed, &uiter)))
2531                 clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val,
2532                                  unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL,
2533                                  GFP_NOFS);
2534         ulist_free(changeset.range_changed);
2535         return ret;
2536 }
2537
2538 static int __btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len,
2539                                        int free)
2540 {
2541         struct extent_changeset changeset;
2542         int ret;
2543
2544         changeset.bytes_changed = 0;
2545         changeset.range_changed = ulist_alloc(GFP_NOFS);
2546         if (!changeset.range_changed)
2547                 return -ENOMEM;
2548
2549         ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
2550                         start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS,
2551                         &changeset);
2552         if (ret < 0)
2553                 goto out;
2554
2555         if (free)
2556                 btrfs_qgroup_free(BTRFS_I(inode)->root,
2557                                   changeset.bytes_changed);
2558 out:
2559         ulist_free(changeset.range_changed);
2560         return ret;
2561 }
2562
2563 /*
2564  * Free a reserved space range from io_tree and related qgroups
2565  *
2566  * Should be called when a range of pages get invalidated before reaching disk.
2567  * Or for error cleanup case.
2568  *
2569  * For data written to disk, use btrfs_qgroup_release_data().
2570  *
2571  * NOTE: This function may sleep for memory allocation.
2572  */
2573 int btrfs_qgroup_free_data(struct inode *inode, u64 start, u64 len)
2574 {
2575         return __btrfs_qgroup_release_data(inode, start, len, 1);
2576 }
2577
2578 /*
2579  * Release a reserved space range from io_tree only.
2580  *
2581  * Should be called when a range of pages get written to disk and corresponding
2582  * FILE_EXTENT is inserted into corresponding root.
2583  *
2584  * Since new qgroup accounting framework will only update qgroup numbers at
2585  * commit_transaction() time, its reserved space shouldn't be freed from
2586  * related qgroups.
2587  *
2588  * But we should release the range from io_tree, to allow further write to be
2589  * COWed.
2590  *
2591  * NOTE: This function may sleep for memory allocation.
2592  */
2593 int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
2594 {
2595         return __btrfs_qgroup_release_data(inode, start, len, 0);
2596 }