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         fs_info->quota_enabled = 0;
 997         fs_info->pending_quota_state = 0;
 998         btrfs_qgroup_wait_for_completion(fs_info);
 999         spin_lock(&fs_info->qgroup_lock);
1000         quota_root = fs_info->quota_root;
1001         fs_info->quota_root = NULL;
1002         fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1003         spin_unlock(&fs_info->qgroup_lock);
1004
1005         btrfs_free_qgroup_config(fs_info);
1006
1007         ret = btrfs_clean_quota_tree(trans, quota_root);
1008         if (ret)
1009                 goto out;
1010
1011         ret = btrfs_del_root(trans, tree_root, &quota_root->root_key);
1012         if (ret)
1013                 goto out;
1014
1015         list_del(&quota_root->dirty_list);
1016
1017         btrfs_tree_lock(quota_root->node);
1018         clean_tree_block(trans, tree_root->fs_info, quota_root->node);
1019         btrfs_tree_unlock(quota_root->node);
1020         btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
1021
1022         free_extent_buffer(quota_root->node);
1023         free_extent_buffer(quota_root->commit_root);
1024         kfree(quota_root);
1025 out:
1026         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1027         return ret;
1028 }
1029
1030 static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1031                          struct btrfs_qgroup *qgroup)
1032 {
1033         if (list_empty(&qgroup->dirty))
1034                 list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1035 }
1036
1037 /*
1038  * The easy accounting, if we are adding/removing the only ref for an extent
1039  * then this qgroup and all of the parent qgroups get their refrence and
1040  * exclusive counts adjusted.
1041  *
1042  * Caller should hold fs_info->qgroup_lock.
1043  */
1044 static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1045                                     struct ulist *tmp, u64 ref_root,
1046                                     u64 num_bytes, int sign)
1047 {
1048         struct btrfs_qgroup *qgroup;
1049         struct btrfs_qgroup_list *glist;
1050         struct ulist_node *unode;
1051         struct ulist_iterator uiter;
1052         int ret = 0;
1053
1054         qgroup = find_qgroup_rb(fs_info, ref_root);
1055         if (!qgroup)
1056                 goto out;
1057
1058         qgroup->rfer += sign * num_bytes;
1059         qgroup->rfer_cmpr += sign * num_bytes;
1060
1061         WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1062         qgroup->excl += sign * num_bytes;
1063         qgroup->excl_cmpr += sign * num_bytes;
1064         if (sign > 0)
1065                 qgroup->reserved -= num_bytes;
1066
1067         qgroup_dirty(fs_info, qgroup);
1068
1069         /* Get all of the parent groups that contain this qgroup */
1070         list_for_each_entry(glist, &qgroup->groups, next_group) {
1071                 ret = ulist_add(tmp, glist->group->qgroupid,
1072                                 ptr_to_u64(glist->group), GFP_ATOMIC);
1073                 if (ret < 0)
1074                         goto out;
1075         }
1076
1077         /* Iterate all of the parents and adjust their reference counts */
1078         ULIST_ITER_INIT(&uiter);
1079         while ((unode = ulist_next(tmp, &uiter))) {
1080                 qgroup = u64_to_ptr(unode->aux);
1081                 qgroup->rfer += sign * num_bytes;
1082                 qgroup->rfer_cmpr += sign * num_bytes;
1083                 WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1084                 qgroup->excl += sign * num_bytes;
1085                 if (sign > 0)
1086                         qgroup->reserved -= num_bytes;
1087                 qgroup->excl_cmpr += sign * num_bytes;
1088                 qgroup_dirty(fs_info, qgroup);
1089
1090                 /* Add any parents of the parents */
1091                 list_for_each_entry(glist, &qgroup->groups, next_group) {
1092                         ret = ulist_add(tmp, glist->group->qgroupid,
1093                                         ptr_to_u64(glist->group), GFP_ATOMIC);
1094                         if (ret < 0)
1095                                 goto out;
1096                 }
1097         }
1098         ret = 0;
1099 out:
1100         return ret;
1101 }
1102
1103
1104 /*
1105  * Quick path for updating qgroup with only excl refs.
1106  *
1107  * In that case, just update all parent will be enough.
1108  * Or we needs to do a full rescan.
1109  * Caller should also hold fs_info->qgroup_lock.
1110  *
1111  * Return 0 for quick update, return >0 for need to full rescan
1112  * and mark INCONSISTENT flag.
1113  * Return < 0 for other error.
1114  */
1115 static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1116                                    struct ulist *tmp, u64 src, u64 dst,
1117                                    int sign)
1118 {
1119         struct btrfs_qgroup *qgroup;
1120         int ret = 1;
1121         int err = 0;
1122
1123         qgroup = find_qgroup_rb(fs_info, src);
1124         if (!qgroup)
1125                 goto out;
1126         if (qgroup->excl == qgroup->rfer) {
1127                 ret = 0;
1128                 err = __qgroup_excl_accounting(fs_info, tmp, dst,
1129                                                qgroup->excl, sign);
1130                 if (err < 0) {
1131                         ret = err;
1132                         goto out;
1133                 }
1134         }
1135 out:
1136         if (ret)
1137                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1138         return ret;
1139 }
1140
1141 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
1142                               struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1143 {
1144         struct btrfs_root *quota_root;
1145         struct btrfs_qgroup *parent;
1146         struct btrfs_qgroup *member;
1147         struct btrfs_qgroup_list *list;
1148         struct ulist *tmp;
1149         int ret = 0;
1150
1151         /* Check the level of src and dst first */
1152         if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1153                 return -EINVAL;
1154
1155         tmp = ulist_alloc(GFP_NOFS);
1156         if (!tmp)
1157                 return -ENOMEM;
1158
1159         mutex_lock(&fs_info->qgroup_ioctl_lock);
1160         quota_root = fs_info->quota_root;
1161         if (!quota_root) {
1162                 ret = -EINVAL;
1163                 goto out;
1164         }
1165         member = find_qgroup_rb(fs_info, src);
1166         parent = find_qgroup_rb(fs_info, dst);
1167         if (!member || !parent) {
1168                 ret = -EINVAL;
1169                 goto out;
1170         }
1171
1172         /* check if such qgroup relation exist firstly */
1173         list_for_each_entry(list, &member->groups, next_group) {
1174                 if (list->group == parent) {
1175                         ret = -EEXIST;
1176                         goto out;
1177                 }
1178         }
1179
1180         ret = add_qgroup_relation_item(trans, quota_root, src, dst);
1181         if (ret)
1182                 goto out;
1183
1184         ret = add_qgroup_relation_item(trans, quota_root, dst, src);
1185         if (ret) {
1186                 del_qgroup_relation_item(trans, quota_root, src, dst);
1187                 goto out;
1188         }
1189
1190         spin_lock(&fs_info->qgroup_lock);
1191         ret = add_relation_rb(quota_root->fs_info, src, dst);
1192         if (ret < 0) {
1193                 spin_unlock(&fs_info->qgroup_lock);
1194                 goto out;
1195         }
1196         ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1197         spin_unlock(&fs_info->qgroup_lock);
1198 out:
1199         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1200         ulist_free(tmp);
1201         return ret;
1202 }
1203
1204 int __del_qgroup_relation(struct btrfs_trans_handle *trans,
1205                               struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1206 {
1207         struct btrfs_root *quota_root;
1208         struct btrfs_qgroup *parent;
1209         struct btrfs_qgroup *member;
1210         struct btrfs_qgroup_list *list;
1211         struct ulist *tmp;
1212         int ret = 0;
1213         int err;
1214
1215         tmp = ulist_alloc(GFP_NOFS);
1216         if (!tmp)
1217                 return -ENOMEM;
1218
1219         quota_root = fs_info->quota_root;
1220         if (!quota_root) {
1221                 ret = -EINVAL;
1222                 goto out;
1223         }
1224
1225         member = find_qgroup_rb(fs_info, src);
1226         parent = find_qgroup_rb(fs_info, dst);
1227         if (!member || !parent) {
1228                 ret = -EINVAL;
1229                 goto out;
1230         }
1231
1232         /* check if such qgroup relation exist firstly */
1233         list_for_each_entry(list, &member->groups, next_group) {
1234                 if (list->group == parent)
1235                         goto exist;
1236         }
1237         ret = -ENOENT;
1238         goto out;
1239 exist:
1240         ret = del_qgroup_relation_item(trans, quota_root, src, dst);
1241         err = del_qgroup_relation_item(trans, quota_root, dst, src);
1242         if (err && !ret)
1243                 ret = err;
1244
1245         spin_lock(&fs_info->qgroup_lock);
1246         del_relation_rb(fs_info, src, dst);
1247         ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1248         spin_unlock(&fs_info->qgroup_lock);
1249 out:
1250         ulist_free(tmp);
1251         return ret;
1252 }
1253
1254 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
1255                               struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1256 {
1257         int ret = 0;
1258
1259         mutex_lock(&fs_info->qgroup_ioctl_lock);
1260         ret = __del_qgroup_relation(trans, fs_info, src, dst);
1261         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1262
1263         return ret;
1264 }
1265
1266 int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
1267                         struct btrfs_fs_info *fs_info, u64 qgroupid)
1268 {
1269         struct btrfs_root *quota_root;
1270         struct btrfs_qgroup *qgroup;
1271         int ret = 0;
1272
1273         mutex_lock(&fs_info->qgroup_ioctl_lock);
1274         quota_root = fs_info->quota_root;
1275         if (!quota_root) {
1276                 ret = -EINVAL;
1277                 goto out;
1278         }
1279         qgroup = find_qgroup_rb(fs_info, qgroupid);
1280         if (qgroup) {
1281                 ret = -EEXIST;
1282                 goto out;
1283         }
1284
1285         ret = add_qgroup_item(trans, quota_root, qgroupid);
1286         if (ret)
1287                 goto out;
1288
1289         spin_lock(&fs_info->qgroup_lock);
1290         qgroup = add_qgroup_rb(fs_info, qgroupid);
1291         spin_unlock(&fs_info->qgroup_lock);
1292
1293         if (IS_ERR(qgroup))
1294                 ret = PTR_ERR(qgroup);
1295 out:
1296         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1297         return ret;
1298 }
1299
1300 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
1301                         struct btrfs_fs_info *fs_info, u64 qgroupid)
1302 {
1303         struct btrfs_root *quota_root;
1304         struct btrfs_qgroup *qgroup;
1305         struct btrfs_qgroup_list *list;
1306         int ret = 0;
1307
1308         mutex_lock(&fs_info->qgroup_ioctl_lock);
1309         quota_root = fs_info->quota_root;
1310         if (!quota_root) {
1311                 ret = -EINVAL;
1312                 goto out;
1313         }
1314
1315         qgroup = find_qgroup_rb(fs_info, qgroupid);
1316         if (!qgroup) {
1317                 ret = -ENOENT;
1318                 goto out;
1319         } else {
1320                 /* check if there are no children of this qgroup */
1321                 if (!list_empty(&qgroup->members)) {
1322                         ret = -EBUSY;
1323                         goto out;
1324                 }
1325         }
1326         ret = del_qgroup_item(trans, quota_root, qgroupid);
1327
1328         while (!list_empty(&qgroup->groups)) {
1329                 list = list_first_entry(&qgroup->groups,
1330                                         struct btrfs_qgroup_list, next_group);
1331                 ret = __del_qgroup_relation(trans, fs_info,
1332                                            qgroupid,
1333                                            list->group->qgroupid);
1334                 if (ret)
1335                         goto out;
1336         }
1337
1338         spin_lock(&fs_info->qgroup_lock);
1339         del_qgroup_rb(quota_root->fs_info, qgroupid);
1340         spin_unlock(&fs_info->qgroup_lock);
1341 out:
1342         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1343         return ret;
1344 }
1345
1346 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans,
1347                        struct btrfs_fs_info *fs_info, u64 qgroupid,
1348                        struct btrfs_qgroup_limit *limit)
1349 {
1350         struct btrfs_root *quota_root;
1351         struct btrfs_qgroup *qgroup;
1352         int ret = 0;
1353         /* Sometimes we would want to clear the limit on this qgroup.
1354          * To meet this requirement, we treat the -1 as a special value
1355          * which tell kernel to clear the limit on this qgroup.
1356          */
1357         const u64 CLEAR_VALUE = -1;
1358
1359         mutex_lock(&fs_info->qgroup_ioctl_lock);
1360         quota_root = fs_info->quota_root;
1361         if (!quota_root) {
1362                 ret = -EINVAL;
1363                 goto out;
1364         }
1365
1366         qgroup = find_qgroup_rb(fs_info, qgroupid);
1367         if (!qgroup) {
1368                 ret = -ENOENT;
1369                 goto out;
1370         }
1371
1372         spin_lock(&fs_info->qgroup_lock);
1373         if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1374                 if (limit->max_rfer == CLEAR_VALUE) {
1375                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1376                         limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1377                         qgroup->max_rfer = 0;
1378                 } else {
1379                         qgroup->max_rfer = limit->max_rfer;
1380                 }
1381         }
1382         if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1383                 if (limit->max_excl == CLEAR_VALUE) {
1384                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1385                         limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1386                         qgroup->max_excl = 0;
1387                 } else {
1388                         qgroup->max_excl = limit->max_excl;
1389                 }
1390         }
1391         if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1392                 if (limit->rsv_rfer == CLEAR_VALUE) {
1393                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1394                         limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1395                         qgroup->rsv_rfer = 0;
1396                 } else {
1397                         qgroup->rsv_rfer = limit->rsv_rfer;
1398                 }
1399         }
1400         if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1401                 if (limit->rsv_excl == CLEAR_VALUE) {
1402                         qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1403                         limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1404                         qgroup->rsv_excl = 0;
1405                 } else {
1406                         qgroup->rsv_excl = limit->rsv_excl;
1407                 }
1408         }
1409         qgroup->lim_flags |= limit->flags;
1410
1411         spin_unlock(&fs_info->qgroup_lock);
1412
1413         ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1414         if (ret) {
1415                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1416                 btrfs_info(fs_info, "unable to update quota limit for %llu",
1417                        qgroupid);
1418         }
1419
1420 out:
1421         mutex_unlock(&fs_info->qgroup_ioctl_lock);
1422         return ret;
1423 }
1424
1425 int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans,
1426                                          struct btrfs_fs_info *fs_info)
1427 {
1428         struct btrfs_qgroup_extent_record *record;
1429         struct btrfs_delayed_ref_root *delayed_refs;
1430         struct rb_node *node;
1431         u64 qgroup_to_skip;
1432         int ret = 0;
1433
1434         delayed_refs = &trans->transaction->delayed_refs;
1435         qgroup_to_skip = delayed_refs->qgroup_to_skip;
1436
1437         /*
1438          * No need to do lock, since this function will only be called in
1439          * btrfs_commmit_transaction().
1440          */
1441         node = rb_first(&delayed_refs->dirty_extent_root);
1442         while (node) {
1443                 record = rb_entry(node, struct btrfs_qgroup_extent_record,
1444                                   node);
1445                 ret = btrfs_find_all_roots(NULL, fs_info, record->bytenr, 0,
1446                                            &record->old_roots);
1447                 if (ret < 0)
1448                         break;
1449                 if (qgroup_to_skip)
1450                         ulist_del(record->old_roots, qgroup_to_skip, 0);
1451                 node = rb_next(node);
1452         }
1453         return ret;
1454 }
1455
1456 struct btrfs_qgroup_extent_record
1457 *btrfs_qgroup_insert_dirty_extent(struct btrfs_delayed_ref_root *delayed_refs,
1458                                   struct btrfs_qgroup_extent_record *record)
1459 {
1460         struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1461         struct rb_node *parent_node = NULL;
1462         struct btrfs_qgroup_extent_record *entry;
1463         u64 bytenr = record->bytenr;
1464
1465         while (*p) {
1466                 parent_node = *p;
1467                 entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1468                                  node);
1469                 if (bytenr < entry->bytenr)
1470                         p = &(*p)->rb_left;
1471                 else if (bytenr > entry->bytenr)
1472                         p = &(*p)->rb_right;
1473                 else
1474                         return entry;
1475         }
1476
1477         rb_link_node(&record->node, parent_node, p);
1478         rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1479         return NULL;
1480 }
1481
1482 #define UPDATE_NEW      0
1483 #define UPDATE_OLD      1
1484 /*
1485  * Walk all of the roots that points to the bytenr and adjust their refcnts.
1486  */
1487 static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
1488                                 struct ulist *roots, struct ulist *tmp,
1489                                 struct ulist *qgroups, u64 seq, int update_old)
1490 {
1491         struct ulist_node *unode;
1492         struct ulist_iterator uiter;
1493         struct ulist_node *tmp_unode;
1494         struct ulist_iterator tmp_uiter;
1495         struct btrfs_qgroup *qg;
1496         int ret = 0;
1497
1498         if (!roots)
1499                 return 0;
1500         ULIST_ITER_INIT(&uiter);
1501         while ((unode = ulist_next(roots, &uiter))) {
1502                 qg = find_qgroup_rb(fs_info, unode->val);
1503                 if (!qg)
1504                         continue;
1505
1506                 ulist_reinit(tmp);
1507                 ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
1508                                 GFP_ATOMIC);
1509                 if (ret < 0)
1510                         return ret;
1511                 ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg), GFP_ATOMIC);
1512                 if (ret < 0)
1513                         return ret;
1514                 ULIST_ITER_INIT(&tmp_uiter);
1515                 while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
1516                         struct btrfs_qgroup_list *glist;
1517
1518                         qg = u64_to_ptr(tmp_unode->aux);
1519                         if (update_old)
1520                                 btrfs_qgroup_update_old_refcnt(qg, seq, 1);
1521                         else
1522                                 btrfs_qgroup_update_new_refcnt(qg, seq, 1);
1523                         list_for_each_entry(glist, &qg->groups, next_group) {
1524                                 ret = ulist_add(qgroups, glist->group->qgroupid,
1525                                                 ptr_to_u64(glist->group),
1526                                                 GFP_ATOMIC);
1527                                 if (ret < 0)
1528                                         return ret;
1529                                 ret = ulist_add(tmp, glist->group->qgroupid,
1530                                                 ptr_to_u64(glist->group),
1531                                                 GFP_ATOMIC);
1532                                 if (ret < 0)
1533                                         return ret;
1534                         }
1535                 }
1536         }
1537         return 0;
1538 }
1539
1540 /*
1541  * Update qgroup rfer/excl counters.
1542  * Rfer update is easy, codes can explain themselves.
1543  *
1544  * Excl update is tricky, the update is split into 2 part.
1545  * Part 1: Possible exclusive <-> sharing detect:
1546  *      |       A       |       !A      |
1547  *  -------------------------------------
1548  *  B   |       *       |       -       |
1549  *  -------------------------------------
1550  *  !B  |       +       |       **      |
1551  *  -------------------------------------
1552  *
1553  * Conditions:
1554  * A:   cur_old_roots < nr_old_roots    (not exclusive before)
1555  * !A:  cur_old_roots == nr_old_roots   (possible exclusive before)
1556  * B:   cur_new_roots < nr_new_roots    (not exclusive now)
1557  * !B:  cur_new_roots == nr_new_roots   (possible exclsuive now)
1558  *
1559  * Results:
1560  * +: Possible sharing -> exclusive     -: Possible exclusive -> sharing
1561  * *: Definitely not changed.           **: Possible unchanged.
1562  *
1563  * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
1564  *
1565  * To make the logic clear, we first use condition A and B to split
1566  * combination into 4 results.
1567  *
1568  * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
1569  * only on variant maybe 0.
1570  *
1571  * Lastly, check result **, since there are 2 variants maybe 0, split them
1572  * again(2x2).
1573  * But this time we don't need to consider other things, the codes and logic
1574  * is easy to understand now.
1575  */
1576 static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
1577                                   struct ulist *qgroups,
1578                                   u64 nr_old_roots,
1579                                   u64 nr_new_roots,
1580                                   u64 num_bytes, u64 seq)
1581 {
1582         struct ulist_node *unode;
1583         struct ulist_iterator uiter;
1584         struct btrfs_qgroup *qg;
1585         u64 cur_new_count, cur_old_count;
1586
1587         ULIST_ITER_INIT(&uiter);
1588         while ((unode = ulist_next(qgroups, &uiter))) {
1589                 bool dirty = false;
1590
1591                 qg = u64_to_ptr(unode->aux);
1592                 cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
1593                 cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
1594
1595                 /* Rfer update part */
1596                 if (cur_old_count == 0 && cur_new_count > 0) {
1597                         qg->rfer += num_bytes;
1598                         qg->rfer_cmpr += num_bytes;
1599                         dirty = true;
1600                 }
1601                 if (cur_old_count > 0 && cur_new_count == 0) {
1602                         qg->rfer -= num_bytes;
1603                         qg->rfer_cmpr -= num_bytes;
1604                         dirty = true;
1605                 }
1606
1607                 /* Excl update part */
1608                 /* Exclusive/none -> shared case */
1609                 if (cur_old_count == nr_old_roots &&
1610                     cur_new_count < nr_new_roots) {
1611                         /* Exclusive -> shared */
1612                         if (cur_old_count != 0) {
1613                                 qg->excl -= num_bytes;
1614                                 qg->excl_cmpr -= num_bytes;
1615                                 dirty = true;
1616                         }
1617                 }
1618
1619                 /* Shared -> exclusive/none case */
1620                 if (cur_old_count < nr_old_roots &&
1621                     cur_new_count == nr_new_roots) {
1622                         /* Shared->exclusive */
1623                         if (cur_new_count != 0) {
1624                                 qg->excl += num_bytes;
1625                                 qg->excl_cmpr += num_bytes;
1626                                 dirty = true;
1627                         }
1628                 }
1629
1630                 /* Exclusive/none -> exclusive/none case */
1631                 if (cur_old_count == nr_old_roots &&
1632                     cur_new_count == nr_new_roots) {
1633                         if (cur_old_count == 0) {
1634                                 /* None -> exclusive/none */
1635
1636                                 if (cur_new_count != 0) {
1637                                         /* None -> exclusive */
1638                                         qg->excl += num_bytes;
1639                                         qg->excl_cmpr += num_bytes;
1640                                         dirty = true;
1641                                 }
1642                                 /* None -> none, nothing changed */
1643                         } else {
1644                                 /* Exclusive -> exclusive/none */
1645
1646                                 if (cur_new_count == 0) {
1647                                         /* Exclusive -> none */
1648                                         qg->excl -= num_bytes;
1649                                         qg->excl_cmpr -= num_bytes;
1650                                         dirty = true;
1651                                 }
1652                                 /* Exclusive -> exclusive, nothing changed */
1653                         }
1654                 }
1655
1656                 if (dirty)
1657                         qgroup_dirty(fs_info, qg);
1658         }
1659         return 0;
1660 }
1661
1662 int
1663 btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans,
1664                             struct btrfs_fs_info *fs_info,
1665                             u64 bytenr, u64 num_bytes,
1666                             struct ulist *old_roots, struct ulist *new_roots)
1667 {
1668         struct ulist *qgroups = NULL;
1669         struct ulist *tmp = NULL;
1670         u64 seq;
1671         u64 nr_new_roots = 0;
1672         u64 nr_old_roots = 0;
1673         int ret = 0;
1674
1675         if (new_roots)
1676                 nr_new_roots = new_roots->nnodes;
1677         if (old_roots)
1678                 nr_old_roots = old_roots->nnodes;
1679
1680         if (!fs_info->quota_enabled)
1681                 goto out_free;
1682         BUG_ON(!fs_info->quota_root);
1683
1684         qgroups = ulist_alloc(GFP_NOFS);
1685         if (!qgroups) {
1686                 ret = -ENOMEM;
1687                 goto out_free;
1688         }
1689         tmp = ulist_alloc(GFP_NOFS);
1690         if (!tmp) {
1691                 ret = -ENOMEM;
1692                 goto out_free;
1693         }
1694
1695         mutex_lock(&fs_info->qgroup_rescan_lock);
1696         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
1697                 if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
1698                         mutex_unlock(&fs_info->qgroup_rescan_lock);
1699                         ret = 0;
1700                         goto out_free;
1701                 }
1702         }
1703         mutex_unlock(&fs_info->qgroup_rescan_lock);
1704
1705         spin_lock(&fs_info->qgroup_lock);
1706         seq = fs_info->qgroup_seq;
1707
1708         /* Update old refcnts using old_roots */
1709         ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
1710                                    UPDATE_OLD);
1711         if (ret < 0)
1712                 goto out;
1713
1714         /* Update new refcnts using new_roots */
1715         ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
1716                                    UPDATE_NEW);
1717         if (ret < 0)
1718                 goto out;
1719
1720         qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
1721                                num_bytes, seq);
1722
1723         /*
1724          * Bump qgroup_seq to avoid seq overlap
1725          */
1726         fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
1727 out:
1728         spin_unlock(&fs_info->qgroup_lock);
1729 out_free:
1730         ulist_free(tmp);
1731         ulist_free(qgroups);
1732         ulist_free(old_roots);
1733         ulist_free(new_roots);
1734         return ret;
1735 }
1736
1737 int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans,
1738                                  struct btrfs_fs_info *fs_info)
1739 {
1740         struct btrfs_qgroup_extent_record *record;
1741         struct btrfs_delayed_ref_root *delayed_refs;
1742         struct ulist *new_roots = NULL;
1743         struct rb_node *node;
1744         u64 qgroup_to_skip;
1745         int ret = 0;
1746
1747         delayed_refs = &trans->transaction->delayed_refs;
1748         qgroup_to_skip = delayed_refs->qgroup_to_skip;
1749         while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
1750                 record = rb_entry(node, struct btrfs_qgroup_extent_record,
1751                                   node);
1752
1753                 if (!ret) {
1754                         /*
1755                          * Use (u64)-1 as time_seq to do special search, which
1756                          * doesn't lock tree or delayed_refs and search current
1757                          * root. It's safe inside commit_transaction().
1758                          */
1759                         ret = btrfs_find_all_roots(trans, fs_info,
1760                                         record->bytenr, (u64)-1, &new_roots);
1761                         if (ret < 0)
1762                                 goto cleanup;
1763                         if (qgroup_to_skip)
1764                                 ulist_del(new_roots, qgroup_to_skip, 0);
1765                         ret = btrfs_qgroup_account_extent(trans, fs_info,
1766                                         record->bytenr, record->num_bytes,
1767                                         record->old_roots, new_roots);
1768                         record->old_roots = NULL;
1769                         new_roots = NULL;
1770                 }
1771 cleanup:
1772                 ulist_free(record->old_roots);
1773                 ulist_free(new_roots);
1774                 new_roots = NULL;
1775                 rb_erase(node, &delayed_refs->dirty_extent_root);
1776                 kfree(record);
1777
1778         }
1779         return ret;
1780 }
1781
1782 /*
1783  * called from commit_transaction. Writes all changed qgroups to disk.
1784  */
1785 int btrfs_run_qgroups(struct btrfs_trans_handle *trans,
1786                       struct btrfs_fs_info *fs_info)
1787 {
1788         struct btrfs_root *quota_root = fs_info->quota_root;
1789         int ret = 0;
1790         int start_rescan_worker = 0;
1791
1792         if (!quota_root)
1793                 goto out;
1794
1795         if (!fs_info->quota_enabled && fs_info->pending_quota_state)
1796                 start_rescan_worker = 1;
1797
1798         fs_info->quota_enabled = fs_info->pending_quota_state;
1799
1800         spin_lock(&fs_info->qgroup_lock);
1801         while (!list_empty(&fs_info->dirty_qgroups)) {
1802                 struct btrfs_qgroup *qgroup;
1803                 qgroup = list_first_entry(&fs_info->dirty_qgroups,
1804                                           struct btrfs_qgroup, dirty);
1805                 list_del_init(&qgroup->dirty);
1806                 spin_unlock(&fs_info->qgroup_lock);
1807                 ret = update_qgroup_info_item(trans, quota_root, qgroup);
1808                 if (ret)
1809                         fs_info->qgroup_flags |=
1810                                         BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1811                 ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1812                 if (ret)
1813                         fs_info->qgroup_flags |=
1814                                         BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1815                 spin_lock(&fs_info->qgroup_lock);
1816         }
1817         if (fs_info->quota_enabled)
1818                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
1819         else
1820                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1821         spin_unlock(&fs_info->qgroup_lock);
1822
1823         ret = update_qgroup_status_item(trans, fs_info, quota_root);
1824         if (ret)
1825                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1826
1827         if (!ret && start_rescan_worker) {
1828                 ret = qgroup_rescan_init(fs_info, 0, 1);
1829                 if (!ret) {
1830                         qgroup_rescan_zero_tracking(fs_info);
1831                         btrfs_queue_work(fs_info->qgroup_rescan_workers,
1832                                          &fs_info->qgroup_rescan_work);
1833                 }
1834                 ret = 0;
1835         }
1836
1837 out:
1838
1839         return ret;
1840 }
1841
1842 /*
1843  * copy the acounting information between qgroups. This is necessary when a
1844  * snapshot or a subvolume is created
1845  */
1846 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans,
1847                          struct btrfs_fs_info *fs_info, u64 srcid, u64 objectid,
1848                          struct btrfs_qgroup_inherit *inherit)
1849 {
1850         int ret = 0;
1851         int i;
1852         u64 *i_qgroups;
1853         struct btrfs_root *quota_root = fs_info->quota_root;
1854         struct btrfs_qgroup *srcgroup;
1855         struct btrfs_qgroup *dstgroup;
1856         u32 level_size = 0;
1857         u64 nums;
1858
1859         mutex_lock(&fs_info->qgroup_ioctl_lock);
1860         if (!fs_info->quota_enabled)
1861                 goto out;
1862
1863         if (!quota_root) {
1864                 ret = -EINVAL;
1865                 goto out;
1866         }
1867
1868         if (inherit) {
1869                 i_qgroups = (u64 *)(inherit + 1);
1870                 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
1871                        2 * inherit->num_excl_copies;
1872                 for (i = 0; i < nums; ++i) {
1873                         srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
1874                         if (!srcgroup) {
1875                                 ret = -EINVAL;
1876                                 goto out;
1877                         }
1878
1879                         if ((srcgroup->qgroupid >> 48) <= (objectid >> 48)) {
1880                                 ret = -EINVAL;
1881                                 goto out;
1882                         }
1883                         ++i_qgroups;
1884                 }
1885         }
1886
1887         /*
1888          * create a tracking group for the subvol itself
1889          */
1890         ret = add_qgroup_item(trans, quota_root, objectid);
1891         if (ret)
1892                 goto out;
1893
1894         if (srcid) {
1895                 struct btrfs_root *srcroot;
1896                 struct btrfs_key srckey;
1897
1898                 srckey.objectid = srcid;
1899                 srckey.type = BTRFS_ROOT_ITEM_KEY;
1900                 srckey.offset = (u64)-1;
1901                 srcroot = btrfs_read_fs_root_no_name(fs_info, &srckey);
1902                 if (IS_ERR(srcroot)) {
1903                         ret = PTR_ERR(srcroot);
1904                         goto out;
1905                 }
1906
1907                 rcu_read_lock();
1908                 level_size = srcroot->nodesize;
1909                 rcu_read_unlock();
1910         }
1911
1912         /*
1913          * add qgroup to all inherited groups
1914          */
1915         if (inherit) {
1916                 i_qgroups = (u64 *)(inherit + 1);
1917                 for (i = 0; i < inherit->num_qgroups; ++i) {
1918                         ret = add_qgroup_relation_item(trans, quota_root,
1919                                                        objectid, *i_qgroups);
1920                         if (ret)
1921                                 goto out;
1922                         ret = add_qgroup_relation_item(trans, quota_root,
1923                                                        *i_qgroups, objectid);
1924                         if (ret)
1925                                 goto out;
1926                         ++i_qgroups;
1927                 }
1928         }
1929
1930
1931         spin_lock(&fs_info->qgroup_lock);
1932
1933         dstgroup = add_qgroup_rb(fs_info, objectid);
1934         if (IS_ERR(dstgroup)) {
1935                 ret = PTR_ERR(dstgroup);
1936                 goto unlock;
1937         }
1938
1939         if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
1940                 dstgroup->lim_flags = inherit->lim.flags;
1941                 dstgroup->max_rfer = inherit->lim.max_rfer;
1942                 dstgroup->max_excl = inherit->lim.max_excl;
1943                 dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
1944                 dstgroup->rsv_excl = inherit->lim.rsv_excl;
1945
1946                 ret = update_qgroup_limit_item(trans, quota_root, dstgroup);
1947                 if (ret) {
1948                         fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1949                         btrfs_info(fs_info, "unable to update quota limit for %llu",
1950                                dstgroup->qgroupid);
1951                         goto unlock;
1952                 }
1953         }
1954
1955         if (srcid) {
1956                 srcgroup = find_qgroup_rb(fs_info, srcid);
1957                 if (!srcgroup)
1958                         goto unlock;
1959
1960                 /*
1961                  * We call inherit after we clone the root in order to make sure
1962                  * our counts don't go crazy, so at this point the only
1963                  * difference between the two roots should be the root node.
1964                  */
1965                 dstgroup->rfer = srcgroup->rfer;
1966                 dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
1967                 dstgroup->excl = level_size;
1968                 dstgroup->excl_cmpr = level_size;
1969                 srcgroup->excl = level_size;
1970                 srcgroup->excl_cmpr = level_size;
1971
1972                 /* inherit the limit info */
1973                 dstgroup->lim_flags = srcgroup->lim_flags;
1974                 dstgroup->max_rfer = srcgroup->max_rfer;
1975                 dstgroup->max_excl = srcgroup->max_excl;
1976                 dstgroup->rsv_rfer = srcgroup->rsv_rfer;
1977                 dstgroup->rsv_excl = srcgroup->rsv_excl;
1978
1979                 qgroup_dirty(fs_info, dstgroup);
1980                 qgroup_dirty(fs_info, srcgroup);
1981         }
1982
1983         if (!inherit)
1984                 goto unlock;
1985
1986         i_qgroups = (u64 *)(inherit + 1);
1987         for (i = 0; i < inherit->num_qgroups; ++i) {
1988                 ret = add_relation_rb(quota_root->fs_info, objectid,
1989                                       *i_qgroups);
1990                 if (ret)
1991                         goto unlock;
1992                 ++i_qgroups;
1993         }
1994
1995         for (i = 0; i <  inherit->num_ref_copies; ++i) {
1996                 struct btrfs_qgroup *src;
1997                 struct btrfs_qgroup *dst;
1998
1999                 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2000                 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2001
2002                 if (!src || !dst) {
2003                         ret = -EINVAL;
2004                         goto unlock;
2005                 }
2006
2007                 dst->rfer = src->rfer - level_size;
2008                 dst->rfer_cmpr = src->rfer_cmpr - level_size;
2009                 i_qgroups += 2;
2010         }
2011         for (i = 0; i <  inherit->num_excl_copies; ++i) {
2012                 struct btrfs_qgroup *src;
2013                 struct btrfs_qgroup *dst;
2014
2015                 src = find_qgroup_rb(fs_info, i_qgroups[0]);
2016                 dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2017
2018                 if (!src || !dst) {
2019                         ret = -EINVAL;
2020                         goto unlock;
2021                 }
2022
2023                 dst->excl = src->excl + level_size;
2024                 dst->excl_cmpr = src->excl_cmpr + level_size;
2025                 i_qgroups += 2;
2026         }
2027
2028 unlock:
2029         spin_unlock(&fs_info->qgroup_lock);
2030 out:
2031         mutex_unlock(&fs_info->qgroup_ioctl_lock);
2032         return ret;
2033 }
2034
2035 static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes)
2036 {
2037         struct btrfs_root *quota_root;
2038         struct btrfs_qgroup *qgroup;
2039         struct btrfs_fs_info *fs_info = root->fs_info;
2040         u64 ref_root = root->root_key.objectid;
2041         int ret = 0;
2042         struct ulist_node *unode;
2043         struct ulist_iterator uiter;
2044
2045         if (!is_fstree(ref_root))
2046                 return 0;
2047
2048         if (num_bytes == 0)
2049                 return 0;
2050
2051         spin_lock(&fs_info->qgroup_lock);
2052         quota_root = fs_info->quota_root;
2053         if (!quota_root)
2054                 goto out;
2055
2056         qgroup = find_qgroup_rb(fs_info, ref_root);
2057         if (!qgroup)
2058                 goto out;
2059
2060         /*
2061          * in a first step, we check all affected qgroups if any limits would
2062          * be exceeded
2063          */
2064         ulist_reinit(fs_info->qgroup_ulist);
2065         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2066                         (uintptr_t)qgroup, GFP_ATOMIC);
2067         if (ret < 0)
2068                 goto out;
2069         ULIST_ITER_INIT(&uiter);
2070         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2071                 struct btrfs_qgroup *qg;
2072                 struct btrfs_qgroup_list *glist;
2073
2074                 qg = u64_to_ptr(unode->aux);
2075
2076                 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2077                     qg->reserved + (s64)qg->rfer + num_bytes >
2078                     qg->max_rfer) {
2079                         ret = -EDQUOT;
2080                         goto out;
2081                 }
2082
2083                 if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2084                     qg->reserved + (s64)qg->excl + num_bytes >
2085                     qg->max_excl) {
2086                         ret = -EDQUOT;
2087                         goto out;
2088                 }
2089
2090                 list_for_each_entry(glist, &qg->groups, next_group) {
2091                         ret = ulist_add(fs_info->qgroup_ulist,
2092                                         glist->group->qgroupid,
2093                                         (uintptr_t)glist->group, GFP_ATOMIC);
2094                         if (ret < 0)
2095                                 goto out;
2096                 }
2097         }
2098         ret = 0;
2099         /*
2100          * no limits exceeded, now record the reservation into all qgroups
2101          */
2102         ULIST_ITER_INIT(&uiter);
2103         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2104                 struct btrfs_qgroup *qg;
2105
2106                 qg = u64_to_ptr(unode->aux);
2107
2108                 qg->reserved += num_bytes;
2109         }
2110
2111 out:
2112         spin_unlock(&fs_info->qgroup_lock);
2113         return ret;
2114 }
2115
2116 void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
2117                                u64 ref_root, u64 num_bytes)
2118 {
2119         struct btrfs_root *quota_root;
2120         struct btrfs_qgroup *qgroup;
2121         struct ulist_node *unode;
2122         struct ulist_iterator uiter;
2123         int ret = 0;
2124
2125         if (!is_fstree(ref_root))
2126                 return;
2127
2128         if (num_bytes == 0)
2129                 return;
2130
2131         spin_lock(&fs_info->qgroup_lock);
2132
2133         quota_root = fs_info->quota_root;
2134         if (!quota_root)
2135                 goto out;
2136
2137         qgroup = find_qgroup_rb(fs_info, ref_root);
2138         if (!qgroup)
2139                 goto out;
2140
2141         ulist_reinit(fs_info->qgroup_ulist);
2142         ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2143                         (uintptr_t)qgroup, GFP_ATOMIC);
2144         if (ret < 0)
2145                 goto out;
2146         ULIST_ITER_INIT(&uiter);
2147         while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2148                 struct btrfs_qgroup *qg;
2149                 struct btrfs_qgroup_list *glist;
2150
2151                 qg = u64_to_ptr(unode->aux);
2152
2153                 qg->reserved -= num_bytes;
2154
2155                 list_for_each_entry(glist, &qg->groups, next_group) {
2156                         ret = ulist_add(fs_info->qgroup_ulist,
2157                                         glist->group->qgroupid,
2158                                         (uintptr_t)glist->group, GFP_ATOMIC);
2159                         if (ret < 0)
2160                                 goto out;
2161                 }
2162         }
2163
2164 out:
2165         spin_unlock(&fs_info->qgroup_lock);
2166 }
2167
2168 static inline void qgroup_free(struct btrfs_root *root, u64 num_bytes)
2169 {
2170         return btrfs_qgroup_free_refroot(root->fs_info, root->objectid,
2171                                          num_bytes);
2172 }
2173 void assert_qgroups_uptodate(struct btrfs_trans_handle *trans)
2174 {
2175         if (list_empty(&trans->qgroup_ref_list) && !trans->delayed_ref_elem.seq)
2176                 return;
2177         btrfs_err(trans->root->fs_info,
2178                 "qgroups not uptodate in trans handle %p:  list is%s empty, "
2179                 "seq is %#x.%x",
2180                 trans, list_empty(&trans->qgroup_ref_list) ? "" : " not",
2181                 (u32)(trans->delayed_ref_elem.seq >> 32),
2182                 (u32)trans->delayed_ref_elem.seq);
2183         BUG();
2184 }
2185
2186 /*
2187  * returns < 0 on error, 0 when more leafs are to be scanned.
2188  * returns 1 when done.
2189  */
2190 static int
2191 qgroup_rescan_leaf(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
2192                    struct btrfs_trans_handle *trans)
2193 {
2194         struct btrfs_key found;
2195         struct extent_buffer *scratch_leaf = NULL;
2196         struct ulist *roots = NULL;
2197         struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
2198         u64 num_bytes;
2199         int slot;
2200         int ret;
2201
2202         mutex_lock(&fs_info->qgroup_rescan_lock);
2203         ret = btrfs_search_slot_for_read(fs_info->extent_root,
2204                                          &fs_info->qgroup_rescan_progress,
2205                                          path, 1, 0);
2206
2207         pr_debug("current progress key (%llu %u %llu), search_slot ret %d\n",
2208                  fs_info->qgroup_rescan_progress.objectid,
2209                  fs_info->qgroup_rescan_progress.type,
2210                  fs_info->qgroup_rescan_progress.offset, ret);
2211
2212         if (ret) {
2213                 /*
2214                  * The rescan is about to end, we will not be scanning any
2215                  * further blocks. We cannot unset the RESCAN flag here, because
2216                  * we want to commit the transaction if everything went well.
2217                  * To make the live accounting work in this phase, we set our
2218                  * scan progress pointer such that every real extent objectid
2219                  * will be smaller.
2220                  */
2221                 fs_info->qgroup_rescan_progress.objectid = (u64)-1;
2222                 btrfs_release_path(path);
2223                 mutex_unlock(&fs_info->qgroup_rescan_lock);
2224                 return ret;
2225         }
2226
2227         btrfs_item_key_to_cpu(path->nodes[0], &found,
2228                               btrfs_header_nritems(path->nodes[0]) - 1);
2229         fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
2230
2231         btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2232         scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
2233         if (!scratch_leaf) {
2234                 ret = -ENOMEM;
2235                 mutex_unlock(&fs_info->qgroup_rescan_lock);
2236                 goto out;
2237         }
2238         extent_buffer_get(scratch_leaf);
2239         btrfs_tree_read_lock(scratch_leaf);
2240         btrfs_set_lock_blocking_rw(scratch_leaf, BTRFS_READ_LOCK);
2241         slot = path->slots[0];
2242         btrfs_release_path(path);
2243         mutex_unlock(&fs_info->qgroup_rescan_lock);
2244
2245         for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
2246                 btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
2247                 if (found.type != BTRFS_EXTENT_ITEM_KEY &&
2248                     found.type != BTRFS_METADATA_ITEM_KEY)
2249                         continue;
2250                 if (found.type == BTRFS_METADATA_ITEM_KEY)
2251                         num_bytes = fs_info->extent_root->nodesize;
2252                 else
2253                         num_bytes = found.offset;
2254
2255                 ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
2256                                            &roots);
2257                 if (ret < 0)
2258                         goto out;
2259                 /* For rescan, just pass old_roots as NULL */
2260                 ret = btrfs_qgroup_account_extent(trans, fs_info,
2261                                 found.objectid, num_bytes, NULL, roots);
2262                 if (ret < 0)
2263                         goto out;
2264         }
2265 out:
2266         if (scratch_leaf) {
2267                 btrfs_tree_read_unlock_blocking(scratch_leaf);
2268                 free_extent_buffer(scratch_leaf);
2269         }
2270         btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2271
2272         return ret;
2273 }
2274
2275 static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
2276 {
2277         struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
2278                                                      qgroup_rescan_work);
2279         struct btrfs_path *path;
2280         struct btrfs_trans_handle *trans = NULL;
2281         int err = -ENOMEM;
2282         int ret = 0;
2283
2284         path = btrfs_alloc_path();
2285         if (!path)
2286                 goto out;
2287
2288         err = 0;
2289         while (!err && !btrfs_fs_closing(fs_info)) {
2290                 trans = btrfs_start_transaction(fs_info->fs_root, 0);
2291                 if (IS_ERR(trans)) {
2292                         err = PTR_ERR(trans);
2293                         break;
2294                 }
2295                 if (!fs_info->quota_enabled) {
2296                         err = -EINTR;
2297                 } else {
2298                         err = qgroup_rescan_leaf(fs_info, path, trans);
2299                 }
2300                 if (err > 0)
2301                         btrfs_commit_transaction(trans, fs_info->fs_root);
2302                 else
2303                         btrfs_end_transaction(trans, fs_info->fs_root);
2304         }
2305
2306 out:
2307         btrfs_free_path(path);
2308
2309         mutex_lock(&fs_info->qgroup_rescan_lock);
2310         if (!btrfs_fs_closing(fs_info))
2311                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2312
2313         if (err > 0 &&
2314             fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
2315                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2316         } else if (err < 0) {
2317                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2318         }
2319         mutex_unlock(&fs_info->qgroup_rescan_lock);
2320
2321         /*
2322          * only update status, since the previous part has alreay updated the
2323          * qgroup info.
2324          */
2325         trans = btrfs_start_transaction(fs_info->quota_root, 1);
2326         if (IS_ERR(trans)) {
2327                 err = PTR_ERR(trans);
2328                 btrfs_err(fs_info,
2329                           "fail to start transaction for status update: %d\n",
2330                           err);
2331                 goto done;
2332         }
2333         ret = update_qgroup_status_item(trans, fs_info, fs_info->quota_root);
2334         if (ret < 0) {
2335                 err = ret;
2336                 btrfs_err(fs_info, "fail to update qgroup status: %d\n", err);
2337         }
2338         btrfs_end_transaction(trans, fs_info->quota_root);
2339
2340         if (btrfs_fs_closing(fs_info)) {
2341                 btrfs_info(fs_info, "qgroup scan paused");
2342         } else if (err >= 0) {
2343                 btrfs_info(fs_info, "qgroup scan completed%s",
2344                         err > 0 ? " (inconsistency flag cleared)" : "");
2345         } else {
2346                 btrfs_err(fs_info, "qgroup scan failed with %d", err);
2347         }
2348
2349 done:
2350         complete_all(&fs_info->qgroup_rescan_completion);
2351 }
2352
2353 /*
2354  * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
2355  * memory required for the rescan context.
2356  */
2357 static int
2358 qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
2359                    int init_flags)
2360 {
2361         int ret = 0;
2362
2363         if (!init_flags &&
2364             (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ||
2365              !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))) {
2366                 ret = -EINVAL;
2367                 goto err;
2368         }
2369
2370         mutex_lock(&fs_info->qgroup_rescan_lock);
2371         spin_lock(&fs_info->qgroup_lock);
2372
2373         if (init_flags) {
2374                 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
2375                         ret = -EINPROGRESS;
2376                 else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
2377                         ret = -EINVAL;
2378
2379                 if (ret) {
2380                         spin_unlock(&fs_info->qgroup_lock);
2381                         mutex_unlock(&fs_info->qgroup_rescan_lock);
2382                         goto err;
2383                 }
2384                 fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2385         }
2386
2387         memset(&fs_info->qgroup_rescan_progress, 0,
2388                 sizeof(fs_info->qgroup_rescan_progress));
2389         fs_info->qgroup_rescan_progress.objectid = progress_objectid;
2390         init_completion(&fs_info->qgroup_rescan_completion);
2391
2392         spin_unlock(&fs_info->qgroup_lock);
2393         mutex_unlock(&fs_info->qgroup_rescan_lock);
2394
2395         memset(&fs_info->qgroup_rescan_work, 0,
2396                sizeof(fs_info->qgroup_rescan_work));
2397         btrfs_init_work(&fs_info->qgroup_rescan_work,
2398                         btrfs_qgroup_rescan_helper,
2399                         btrfs_qgroup_rescan_worker, NULL, NULL);
2400
2401         if (ret) {
2402 err:
2403                 btrfs_info(fs_info, "qgroup_rescan_init failed with %d", ret);
2404                 return ret;
2405         }
2406
2407         return 0;
2408 }
2409
2410 static void
2411 qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
2412 {
2413         struct rb_node *n;
2414         struct btrfs_qgroup *qgroup;
2415
2416         spin_lock(&fs_info->qgroup_lock);
2417         /* clear all current qgroup tracking information */
2418         for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
2419                 qgroup = rb_entry(n, struct btrfs_qgroup, node);
2420                 qgroup->rfer = 0;
2421                 qgroup->rfer_cmpr = 0;
2422                 qgroup->excl = 0;
2423                 qgroup->excl_cmpr = 0;
2424         }
2425         spin_unlock(&fs_info->qgroup_lock);
2426 }
2427
2428 int
2429 btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
2430 {
2431         int ret = 0;
2432         struct btrfs_trans_handle *trans;
2433
2434         ret = qgroup_rescan_init(fs_info, 0, 1);
2435         if (ret)
2436                 return ret;
2437
2438         /*
2439          * We have set the rescan_progress to 0, which means no more
2440          * delayed refs will be accounted by btrfs_qgroup_account_ref.
2441          * However, btrfs_qgroup_account_ref may be right after its call
2442          * to btrfs_find_all_roots, in which case it would still do the
2443          * accounting.
2444          * To solve this, we're committing the transaction, which will
2445          * ensure we run all delayed refs and only after that, we are
2446          * going to clear all tracking information for a clean start.
2447          */
2448
2449         trans = btrfs_join_transaction(fs_info->fs_root);
2450         if (IS_ERR(trans)) {
2451                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2452                 return PTR_ERR(trans);
2453         }
2454         ret = btrfs_commit_transaction(trans, fs_info->fs_root);
2455         if (ret) {
2456                 fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2457                 return ret;
2458         }
2459
2460         qgroup_rescan_zero_tracking(fs_info);
2461
2462         btrfs_queue_work(fs_info->qgroup_rescan_workers,
2463                          &fs_info->qgroup_rescan_work);
2464
2465         return 0;
2466 }
2467
2468 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info)
2469 {
2470         int running;
2471         int ret = 0;
2472
2473         mutex_lock(&fs_info->qgroup_rescan_lock);
2474         spin_lock(&fs_info->qgroup_lock);
2475         running = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2476         spin_unlock(&fs_info->qgroup_lock);
2477         mutex_unlock(&fs_info->qgroup_rescan_lock);
2478
2479         if (running)
2480                 ret = wait_for_completion_interruptible(
2481                                         &fs_info->qgroup_rescan_completion);
2482
2483         return ret;
2484 }
2485
2486 /*
2487  * this is only called from open_ctree where we're still single threaded, thus
2488  * locking is omitted here.
2489  */
2490 void
2491 btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
2492 {
2493         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
2494                 btrfs_queue_work(fs_info->qgroup_rescan_workers,
2495                                  &fs_info->qgroup_rescan_work);
2496 }
2497
2498 /*
2499  * Reserve qgroup space for range [start, start + len).
2500  *
2501  * This function will either reserve space from related qgroups or doing
2502  * nothing if the range is already reserved.
2503  *
2504  * Return 0 for successful reserve
2505  * Return <0 for error (including -EQUOT)
2506  *
2507  * NOTE: this function may sleep for memory allocation.
2508  */
2509 int btrfs_qgroup_reserve_data(struct inode *inode, u64 start, u64 len)
2510 {
2511         struct btrfs_root *root = BTRFS_I(inode)->root;
2512         struct extent_changeset changeset;
2513         struct ulist_node *unode;
2514         struct ulist_iterator uiter;
2515         int ret;
2516
2517         if (!root->fs_info->quota_enabled || !is_fstree(root->objectid) ||
2518             len == 0)
2519                 return 0;
2520
2521         changeset.bytes_changed = 0;
2522         changeset.range_changed = ulist_alloc(GFP_NOFS);
2523         ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
2524                         start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS,
2525                         &changeset);
2526         trace_btrfs_qgroup_reserve_data(inode, start, len,
2527                                         changeset.bytes_changed,
2528                                         QGROUP_RESERVE);
2529         if (ret < 0)
2530                 goto cleanup;
2531         ret = qgroup_reserve(root, changeset.bytes_changed);
2532         if (ret < 0)
2533                 goto cleanup;
2534
2535         ulist_free(changeset.range_changed);
2536         return ret;
2537
2538 cleanup:
2539         /* cleanup already reserved ranges */
2540         ULIST_ITER_INIT(&uiter);
2541         while ((unode = ulist_next(changeset.range_changed, &uiter)))
2542                 clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val,
2543                                  unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL,
2544                                  GFP_NOFS);
2545         ulist_free(changeset.range_changed);
2546         return ret;
2547 }
2548
2549 static int __btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len,
2550                                        int free)
2551 {
2552         struct extent_changeset changeset;
2553         int trace_op = QGROUP_RELEASE;
2554         int ret;
2555
2556         changeset.bytes_changed = 0;
2557         changeset.range_changed = ulist_alloc(GFP_NOFS);
2558         if (!changeset.range_changed)
2559                 return -ENOMEM;
2560
2561         ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
2562                         start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS,
2563                         &changeset);
2564         if (ret < 0)
2565                 goto out;
2566
2567         if (free) {
2568                 qgroup_free(BTRFS_I(inode)->root, changeset.bytes_changed);
2569                 trace_op = QGROUP_FREE;
2570         }
2571         trace_btrfs_qgroup_release_data(inode, start, len,
2572                                         changeset.bytes_changed, trace_op);
2573 out:
2574         ulist_free(changeset.range_changed);
2575         return ret;
2576 }
2577
2578 /*
2579  * Free a reserved space range from io_tree and related qgroups
2580  *
2581  * Should be called when a range of pages get invalidated before reaching disk.
2582  * Or for error cleanup case.
2583  *
2584  * For data written to disk, use btrfs_qgroup_release_data().
2585  *
2586  * NOTE: This function may sleep for memory allocation.
2587  */
2588 int btrfs_qgroup_free_data(struct inode *inode, u64 start, u64 len)
2589 {
2590         return __btrfs_qgroup_release_data(inode, start, len, 1);
2591 }
2592
2593 /*
2594  * Release a reserved space range from io_tree only.
2595  *
2596  * Should be called when a range of pages get written to disk and corresponding
2597  * FILE_EXTENT is inserted into corresponding root.
2598  *
2599  * Since new qgroup accounting framework will only update qgroup numbers at
2600  * commit_transaction() time, its reserved space shouldn't be freed from
2601  * related qgroups.
2602  *
2603  * But we should release the range from io_tree, to allow further write to be
2604  * COWed.
2605  *
2606  * NOTE: This function may sleep for memory allocation.
2607  */
2608 int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
2609 {
2610         return __btrfs_qgroup_release_data(inode, start, len, 0);
2611 }
2612
2613 int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes)
2614 {
2615         int ret;
2616
2617         if (!root->fs_info->quota_enabled || !is_fstree(root->objectid) ||
2618             num_bytes == 0)
2619                 return 0;
2620
2621         BUG_ON(num_bytes != round_down(num_bytes, root->nodesize));
2622         ret = qgroup_reserve(root, num_bytes);
2623         if (ret < 0)
2624                 return ret;
2625         atomic_add(num_bytes, &root->qgroup_meta_rsv);
2626         return ret;
2627 }
2628
2629 void btrfs_qgroup_free_meta_all(struct btrfs_root *root)
2630 {
2631         int reserved;
2632
2633         if (!root->fs_info->quota_enabled || !is_fstree(root->objectid))
2634                 return;
2635
2636         reserved = atomic_xchg(&root->qgroup_meta_rsv, 0);
2637         if (reserved == 0)
2638                 return;
2639         qgroup_free(root, reserved);
2640 }
2641
2642 void btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes)
2643 {
2644         if (!root->fs_info->quota_enabled || !is_fstree(root->objectid))
2645                 return;
2646
2647         BUG_ON(num_bytes != round_down(num_bytes, root->nodesize));
2648         WARN_ON(atomic_read(&root->qgroup_meta_rsv) < num_bytes);
2649         atomic_sub(num_bytes, &root->qgroup_meta_rsv);
2650         qgroup_free(root, num_bytes);
2651 }
2652
2653 /*
2654  * Check qgroup reserved space leaking, normally at destory inode
2655  * time
2656  */
2657 void btrfs_qgroup_check_reserved_leak(struct inode *inode)
2658 {
2659         struct extent_changeset changeset;
2660         struct ulist_node *unode;
2661         struct ulist_iterator iter;
2662         int ret;
2663
2664         changeset.bytes_changed = 0;
2665         changeset.range_changed = ulist_alloc(GFP_NOFS);
2666         if (WARN_ON(!changeset.range_changed))
2667                 return;
2668
2669         ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
2670                         EXTENT_QGROUP_RESERVED, GFP_NOFS, &changeset);
2671
2672         WARN_ON(ret < 0);
2673         if (WARN_ON(changeset.bytes_changed)) {
2674                 ULIST_ITER_INIT(&iter);
2675                 while ((unode = ulist_next(changeset.range_changed, &iter))) {
2676                         btrfs_warn(BTRFS_I(inode)->root->fs_info,
2677                                 "leaking qgroup reserved space, ino: %lu, start: %llu, end: %llu",
2678                                 inode->i_ino, unode->val, unode->aux);
2679                 }
2680                 qgroup_free(BTRFS_I(inode)->root, changeset.bytes_changed);
2681         }
2682         ulist_free(changeset.range_changed);
2683 }