qgroup.c

   1 /*
   2  * Copyright (C) 2012 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 "qgroup.h"
  20 #include <sys/ioctl.h>
  21 #include "ctree.h"
  22 #include "ioctl.h"
  23
  24 #define BTRFS_QGROUP_NFILTERS_INCREASE (2 * BTRFS_QGROUP_FILTER_MAX)
  25 #define BTRFS_QGROUP_NCOMPS_INCREASE (2 * BTRFS_QGROUP_COMP_MAX)
  26
  27 struct qgroup_lookup {
  28         struct rb_root root;
  29 };
  30
  31 struct btrfs_qgroup {
  32         struct rb_node rb_node;
  33         struct rb_node sort_node;
  34         /*
  35          *all_parent_node is used to
  36          *filter a qgroup's all parent
  37          */
  38         struct rb_node all_parent_node;
  39         u64 qgroupid;
  40
  41         /*
  42          * info_item
  43          */
  44         u64 generation;
  45         u64 rfer;       /*referenced*/
  46         u64 rfer_cmpr;  /*referenced compressed*/
  47         u64 excl;       /*exclusive*/
  48         u64 excl_cmpr;  /*exclusive compressed*/
  49
  50         /*
  51          *limit_item
  52          */
  53         u64 flags;      /*which limits are set*/
  54         u64 max_rfer;
  55         u64 max_excl;
  56         u64 rsv_rfer;
  57         u64 rsv_excl;
  58
  59         /*qgroups this group is member of*/
  60         struct list_head qgroups;
  61         /*qgroups that are members of this group*/
  62         struct list_head members;
  63 };
  64
  65 /*
  66  * glue structure to represent the relations
  67  * between qgroups
  68  */
  69 struct btrfs_qgroup_list {
  70         struct list_head next_qgroup;
  71         struct list_head next_member;
  72         struct btrfs_qgroup *qgroup;
  73         struct btrfs_qgroup *member;
  74 };
  75
  76 /*
  77  * qgroupid,rfer,excl default to set
  78  */
  79 struct {
  80         char *name;
  81         char *column_name;
  82         int need_print;
  83         int max_len;
  84 } btrfs_qgroup_columns[] = {
  85         {
  86                 .name           = "qgroupid",
  87                 .column_name    = "Qgroupid",
  88                 .need_print     = 1,
  89                 .max_len        = 8,
  90         },
  91         {
  92                 .name           = "rfer",
  93                 .column_name    = "Rfer",
  94                 .need_print     = 1,
  95                 .max_len        = 4,
  96         },
  97         {
  98                 .name           = "excl",
  99                 .column_name    = "Excl",
 100                 .need_print     = 1,
 101                 .max_len        = 4,
 102         },
 103         {       .name           = "max_rfer",
 104                 .column_name    = "Max_rfer",
 105                 .need_print     = 0,
 106                 .max_len        = 8,
 107         },
 108         {
 109                 .name           = "max_excl",
 110                 .column_name    = "Max_excl",
 111                 .need_print     = 0,
 112                 .max_len        = 8,
 113         },
 114         {
 115                 .name           = "parent",
 116                 .column_name    = "Parent",
 117                 .need_print     = 0,
 118                 .max_len        = 7,
 119         },
 120         {
 121                 .name           = "child",
 122                 .column_name    = "Child",
 123                 .need_print     = 0,
 124                 .max_len        = 5,
 125         },
 126         {
 127                 .name           = NULL,
 128                 .column_name    = NULL,
 129                 .need_print     = 0,
 130         },
 131 };
 132
 133 static btrfs_qgroup_filter_func all_filter_funcs[];
 134 static btrfs_qgroup_comp_func all_comp_funcs[];
 135
 136 void btrfs_qgroup_setup_print_column(enum btrfs_qgroup_column_enum column)
 137 {
 138         int i;
 139
 140         BUG_ON(column < 0 || column > BTRFS_QGROUP_ALL);
 141
 142         if (column < BTRFS_QGROUP_ALL) {
 143                 btrfs_qgroup_columns[column].need_print = 1;
 144                 return;
 145         }
 146         for (i = 0; i < BTRFS_QGROUP_ALL; i++)
 147                 btrfs_qgroup_columns[i].need_print = 1;
 148 }
 149
 150 static int print_parent_column(struct btrfs_qgroup *qgroup)
 151 {
 152         struct btrfs_qgroup_list *list = NULL;
 153         int len = 0;
 154
 155         list_for_each_entry(list, &qgroup->qgroups, next_qgroup) {
 156                 len += printf("%llu/%llu", (list->qgroup)->qgroupid >> 48,
 157                         ((1ll << 48) - 1) & (list->qgroup)->qgroupid);
 158                 if (!list_is_last(&list->next_qgroup, &qgroup->qgroups))
 159                         len += printf(",");
 160         }
 161         if (list_empty(&qgroup->qgroups))
 162                 len += printf("---");
 163
 164         return len;
 165 }
 166
 167 static int print_child_column(struct btrfs_qgroup *qgroup)
 168 {
 169         struct btrfs_qgroup_list *list = NULL;
 170         int len = 0;
 171
 172         list_for_each_entry(list, &qgroup->members, next_member) {
 173                 len += printf("%llu/%llu", (list->member)->qgroupid >> 48,
 174                                 ((1ll << 48) - 1) & (list->member)->qgroupid);
 175                 if (!list_is_last(&list->next_member, &qgroup->members))
 176                         len += printf(",");
 177         }
 178         if (list_empty(&qgroup->members))
 179                 len += printf("---");
 180
 181         return len;
 182 }
 183
 184 static void print_qgroup_column_add_blank(enum btrfs_qgroup_column_enum column,
 185                                           int len)
 186 {
 187         len = btrfs_qgroup_columns[column].max_len - len;
 188         while (len--)
 189                 printf(" ");
 190 }
 191
 192 static void print_qgroup_column(struct btrfs_qgroup *qgroup,
 193                                 enum btrfs_qgroup_column_enum column)
 194 {
 195         BUG_ON(column >= BTRFS_QGROUP_ALL || column < 0);
 196         int len;
 197
 198         switch (column) {
 199
 200         case BTRFS_QGROUP_QGROUPID:
 201                 len = printf("%llu/%llu", qgroup->qgroupid >> 48,
 202                                 ((1ll << 48) - 1) & qgroup->qgroupid);
 203                 print_qgroup_column_add_blank(BTRFS_QGROUP_QGROUPID, len);
 204                 break;
 205         case BTRFS_QGROUP_RFER:
 206                 len = printf("%lld", qgroup->rfer);
 207                 print_qgroup_column_add_blank(BTRFS_QGROUP_RFER, len);
 208                 break;
 209         case BTRFS_QGROUP_EXCL:
 210                 len = printf("%lld", qgroup->excl);
 211                 print_qgroup_column_add_blank(BTRFS_QGROUP_EXCL, len);
 212                 break;
 213         case BTRFS_QGROUP_PARENT:
 214                 len = print_parent_column(qgroup);
 215                 print_qgroup_column_add_blank(BTRFS_QGROUP_PARENT, len);
 216                 break;
 217         case BTRFS_QGROUP_MAX_RFER:
 218                 len = printf("%llu", qgroup->max_rfer);
 219                 print_qgroup_column_add_blank(BTRFS_QGROUP_MAX_RFER, len);
 220                 break;
 221         case BTRFS_QGROUP_MAX_EXCL:
 222                 len = printf("%llu", qgroup->max_excl);
 223                 print_qgroup_column_add_blank(BTRFS_QGROUP_MAX_EXCL, len);
 224                 break;
 225         case BTRFS_QGROUP_CHILD:
 226                 len = print_child_column(qgroup);
 227                 print_qgroup_column_add_blank(BTRFS_QGROUP_CHILD, len);
 228                 break;
 229         default:
 230                 break;
 231         }
 232 }
 233
 234 static void print_single_qgroup_table(struct btrfs_qgroup *qgroup)
 235 {
 236         int i;
 237
 238         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 239                 if (!btrfs_qgroup_columns[i].need_print)
 240                         continue;
 241                 print_qgroup_column(qgroup, i);
 242
 243                 if (i != BTRFS_QGROUP_CHILD)
 244                         printf(" ");
 245         }
 246         printf("\n");
 247 }
 248
 249 static void print_table_head()
 250 {
 251         int i;
 252         int len;
 253
 254         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 255                 if (!btrfs_qgroup_columns[i].need_print)
 256                         continue;
 257                 printf("%s", btrfs_qgroup_columns[i].name);
 258                 len = btrfs_qgroup_columns[i].max_len -
 259                       strlen(btrfs_qgroup_columns[i].name);
 260                 while (len--)
 261                         printf(" ");
 262                 printf(" ");
 263         }
 264         printf("\n");
 265         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 266                 if (!btrfs_qgroup_columns[i].need_print)
 267                         continue;
 268
 269                 len = strlen(btrfs_qgroup_columns[i].name);
 270                 while (len--)
 271                         printf("-");
 272                 len = btrfs_qgroup_columns[i].max_len -
 273                       strlen(btrfs_qgroup_columns[i].name);
 274                 printf(" ");
 275                 while (len--)
 276                         printf(" ");
 277         }
 278         printf("\n");
 279 }
 280
 281 static void qgroup_lookup_init(struct qgroup_lookup *tree)
 282 {
 283         tree->root.rb_node = NULL;
 284 }
 285
 286 static int comp_entry_with_qgroupid(struct btrfs_qgroup *entry1,
 287                                     struct btrfs_qgroup *entry2,
 288                                     int is_descending)
 289 {
 290
 291         int ret;
 292
 293         if (entry1->qgroupid > entry2->qgroupid)
 294                 ret = 1;
 295         else if (entry1->qgroupid < entry2->qgroupid)
 296                 ret = -1;
 297         else
 298                 ret = 0;
 299
 300         return is_descending ? -ret : ret;
 301 }
 302
 303 static int comp_entry_with_rfer(struct btrfs_qgroup *entry1,
 304                                 struct btrfs_qgroup *entry2,
 305                                 int is_descending)
 306 {
 307         int ret;
 308
 309         if (entry1->rfer > entry2->rfer)
 310                 ret = 1;
 311         else if (entry1->rfer < entry2->rfer)
 312                 ret = -1;
 313         else
 314                 ret = 0;
 315
 316         return is_descending ? -ret : ret;
 317 }
 318
 319 static int comp_entry_with_excl(struct btrfs_qgroup *entry1,
 320                                 struct btrfs_qgroup *entry2,
 321                                 int is_descending)
 322 {
 323         int ret;
 324
 325         if (entry1->excl > entry2->excl)
 326                 ret = 1;
 327         else if (entry1->excl < entry2->excl)
 328                 ret = -1;
 329         else
 330                 ret = 0;
 331
 332         return is_descending ? -ret : ret;
 333 }
 334
 335 static int comp_entry_with_max_rfer(struct btrfs_qgroup *entry1,
 336                                     struct btrfs_qgroup *entry2,
 337                                     int is_descending)
 338 {
 339         int ret;
 340
 341         if (entry1->max_rfer > entry2->max_rfer)
 342                 ret = 1;
 343         else if (entry1->max_rfer < entry2->max_rfer)
 344                 ret = -1;
 345         else
 346                 ret = 0;
 347
 348         return is_descending ? -ret : ret;
 349 }
 350
 351 static int comp_entry_with_max_excl(struct btrfs_qgroup *entry1,
 352                                     struct btrfs_qgroup *entry2,
 353                                     int is_descending)
 354 {
 355         int ret;
 356
 357         if (entry1->max_excl > entry2->max_excl)
 358                 ret = 1;
 359         else if (entry1->max_excl < entry2->max_excl)
 360                 ret = -1;
 361         else
 362                 ret = 0;
 363
 364         return is_descending ? -ret : ret;
 365 }
 366
 367 static btrfs_qgroup_comp_func all_comp_funcs[] = {
 368         [BTRFS_QGROUP_COMP_QGROUPID]    = comp_entry_with_qgroupid,
 369         [BTRFS_QGROUP_COMP_RFER]        = comp_entry_with_rfer,
 370         [BTRFS_QGROUP_COMP_EXCL]        = comp_entry_with_excl,
 371         [BTRFS_QGROUP_COMP_MAX_RFER]    = comp_entry_with_max_rfer,
 372         [BTRFS_QGROUP_COMP_MAX_EXCL]    = comp_entry_with_max_excl
 373 };
 374
 375 static char *all_sort_items[] = {
 376         [BTRFS_QGROUP_COMP_QGROUPID]    = "qgroupid",
 377         [BTRFS_QGROUP_COMP_RFER]        = "rfer",
 378         [BTRFS_QGROUP_COMP_EXCL]        = "excl",
 379         [BTRFS_QGROUP_COMP_MAX_RFER]    = "max_rfer",
 380         [BTRFS_QGROUP_COMP_MAX_EXCL]    = "max_excl",
 381         [BTRFS_QGROUP_COMP_MAX]         = NULL,
 382 };
 383
 384 static int  btrfs_qgroup_get_sort_item(char *sort_name)
 385 {
 386         int i;
 387
 388         for (i = 0; i < BTRFS_QGROUP_COMP_MAX; i++) {
 389                 if (strcmp(sort_name, all_sort_items[i]) == 0)
 390                         return i;
 391         }
 392         return -1;
 393 }
 394
 395 struct btrfs_qgroup_comparer_set *btrfs_qgroup_alloc_comparer_set(void)
 396 {
 397         struct btrfs_qgroup_comparer_set *set;
 398         int size;
 399         size = sizeof(struct btrfs_qgroup_comparer_set) +
 400                BTRFS_QGROUP_NCOMPS_INCREASE *
 401                sizeof(struct btrfs_qgroup_comparer);
 402         set = malloc(size);
 403         if (!set) {
 404                 fprintf(stderr, "memory allocation failed\n");
 405                 exit(1);
 406         }
 407
 408         memset(set, 0, size);
 409         set->total = BTRFS_QGROUP_NCOMPS_INCREASE;
 410
 411         return set;
 412 }
 413
 414 void btrfs_qgroup_free_comparer_set(struct btrfs_qgroup_comparer_set *comp_set)
 415 {
 416         free(comp_set);
 417 }
 418
 419 int btrfs_qgroup_setup_comparer(struct btrfs_qgroup_comparer_set  **comp_set,
 420                                 enum btrfs_qgroup_comp_enum comparer,
 421                                 int is_descending)
 422 {
 423         struct btrfs_qgroup_comparer_set *set = *comp_set;
 424         int size;
 425
 426         BUG_ON(!set);
 427         BUG_ON(comparer >= BTRFS_QGROUP_COMP_MAX);
 428         BUG_ON(set->ncomps > set->total);
 429
 430         if (set->ncomps == set->total) {
 431                 size = set->total + BTRFS_QGROUP_NCOMPS_INCREASE;
 432                 size = sizeof(*set) +
 433                        size * sizeof(struct btrfs_qgroup_comparer);
 434                 set = realloc(set, size);
 435                 if (!set) {
 436                         fprintf(stderr, "memory allocation failed\n");
 437                         exit(1);
 438                 }
 439
 440                 memset(&set->comps[set->total], 0,
 441                        BTRFS_QGROUP_NCOMPS_INCREASE *
 442                        sizeof(struct btrfs_qgroup_comparer));
 443                 set->total += BTRFS_QGROUP_NCOMPS_INCREASE;
 444                 *comp_set = set;
 445         }
 446
 447         BUG_ON(set->comps[set->ncomps].comp_func);
 448
 449         set->comps[set->ncomps].comp_func = all_comp_funcs[comparer];
 450         set->comps[set->ncomps].is_descending = is_descending;
 451         set->ncomps++;
 452         return 0;
 453 }
 454
 455 static int sort_comp(struct btrfs_qgroup *entry1, struct btrfs_qgroup *entry2,
 456                      struct btrfs_qgroup_comparer_set *set)
 457 {
 458         int qgroupid_compared = 0;
 459         int i, ret = 0;
 460
 461         if (!set || !set->ncomps)
 462                 goto comp_qgroupid;
 463
 464         for (i = 0; i < set->ncomps; i++) {
 465                 if (!set->comps[i].comp_func)
 466                         break;
 467
 468                 ret = set->comps[i].comp_func(entry1, entry2,
 469                                               set->comps[i].is_descending);
 470                 if (ret)
 471                         return ret;
 472
 473                 if (set->comps[i].comp_func == comp_entry_with_qgroupid)
 474                         qgroupid_compared = 1;
 475         }
 476
 477         if (!qgroupid_compared) {
 478 comp_qgroupid:
 479                 ret = comp_entry_with_qgroupid(entry1, entry2, 0);
 480         }
 481
 482         return ret;
 483 }
 484
 485 /*
 486  * insert a new root into the tree.  returns the existing root entry
 487  * if one is already there.  qgroupid is used
 488  * as the key
 489  */
 490 static int qgroup_tree_insert(struct qgroup_lookup *root_tree,
 491                               struct btrfs_qgroup *ins)
 492 {
 493
 494         struct rb_node **p = &root_tree->root.rb_node;
 495         struct rb_node *parent = NULL;
 496         struct btrfs_qgroup *curr;
 497         int ret;
 498
 499         while (*p) {
 500                 parent = *p;
 501                 curr = rb_entry(parent, struct btrfs_qgroup, rb_node);
 502
 503                 ret = comp_entry_with_qgroupid(ins, curr, 0);
 504                 if (ret < 0)
 505                         p = &(*p)->rb_left;
 506                 else if (ret > 0)
 507                         p = &(*p)->rb_right;
 508                 else
 509                         return -EEXIST;
 510         }
 511         rb_link_node(&ins->rb_node, parent, p);
 512         rb_insert_color(&ins->rb_node, &root_tree->root);
 513         return 0;
 514 }
 515
 516 /*
 517  *find a given qgroupid in the tree. We return the smallest one,
 518  *rb_next can be used to move forward looking for more if required
 519  */
 520 static struct btrfs_qgroup *qgroup_tree_search(struct qgroup_lookup *root_tree,
 521                                                u64 qgroupid)
 522 {
 523         struct rb_node *n = root_tree->root.rb_node;
 524         struct btrfs_qgroup *entry;
 525         struct btrfs_qgroup tmp;
 526         int ret;
 527
 528         tmp.qgroupid = qgroupid;
 529
 530         while (n) {
 531                 entry = rb_entry(n, struct btrfs_qgroup, rb_node);
 532
 533                 ret = comp_entry_with_qgroupid(&tmp, entry, 0);
 534                 if (ret < 0)
 535                         n = n->rb_left;
 536                 else if (ret > 0)
 537                         n = n->rb_right;
 538                 else
 539                         return entry;
 540
 541         }
 542         return NULL;
 543 }
 544
 545 static int update_qgroup(struct qgroup_lookup *qgroup_lookup, u64 qgroupid,
 546                          u64 generation, u64 rfer, u64 rfer_cmpr, u64 excl,
 547                          u64 excl_cmpr, u64 flags, u64 max_rfer, u64 max_excl,
 548                          u64 rsv_rfer, u64 rsv_excl, struct btrfs_qgroup *pa,
 549                          struct btrfs_qgroup *child)
 550 {
 551         struct btrfs_qgroup *bq;
 552         struct btrfs_qgroup_list *list;
 553
 554         bq = qgroup_tree_search(qgroup_lookup, qgroupid);
 555         if (!bq || bq->qgroupid != qgroupid)
 556                 return -ENOENT;
 557
 558         if (generation)
 559                 bq->generation = generation;
 560         if (rfer)
 561                 bq->rfer = rfer;
 562         if (rfer_cmpr)
 563                 bq->rfer_cmpr = rfer_cmpr;
 564         if (excl)
 565                 bq->excl = excl;
 566         if (excl_cmpr)
 567                 bq->excl_cmpr = excl_cmpr;
 568         if (flags)
 569                 bq->flags = flags;
 570         if (max_rfer)
 571                 bq->max_rfer = max_rfer;
 572         if (max_excl)
 573                 bq->max_excl = max_excl;
 574         if (rsv_rfer)
 575                 bq->rsv_rfer = rsv_rfer;
 576         if (pa && child) {
 577                 list = malloc(sizeof(*list));
 578                 if (!list) {
 579                         fprintf(stderr, "memory allocation failed\n");
 580                         exit(1);
 581                 }
 582                 list->qgroup = pa;
 583                 list->member = child;
 584                 list_add_tail(&list->next_qgroup, &child->qgroups);
 585                 list_add_tail(&list->next_member, &pa->members);
 586         }
 587         return 0;
 588 }
 589
 590 static int add_qgroup(struct qgroup_lookup *qgroup_lookup, u64 qgroupid,
 591                       u64 generation, u64 rfer, u64 rfer_cmpr, u64 excl,
 592                       u64 excl_cmpr, u64 flags, u64 max_rfer, u64 max_excl,
 593                       u64 rsv_rfer, u64 rsv_excl, struct btrfs_qgroup *parent,
 594                       struct btrfs_qgroup *child)
 595 {
 596         struct btrfs_qgroup *bq;
 597         struct btrfs_qgroup_list *list;
 598         int ret;
 599
 600         ret = update_qgroup(qgroup_lookup, qgroupid, generation, rfer,
 601                             rfer_cmpr, excl, excl_cmpr, flags, max_rfer,
 602                             max_excl, rsv_rfer, rsv_excl, parent, child);
 603         if (!ret)
 604                 return 0;
 605
 606         bq = malloc(sizeof(*bq));
 607         if (!bq) {
 608                 printf("memory allocation failed\n");
 609                 exit(1);
 610         }
 611         memset(bq, 0, sizeof(*bq));
 612         if (qgroupid) {
 613                 bq->qgroupid = qgroupid;
 614                 INIT_LIST_HEAD(&bq->qgroups);
 615                 INIT_LIST_HEAD(&bq->members);
 616         }
 617         if (generation)
 618                 bq->generation = generation;
 619         if (rfer)
 620                 bq->rfer = rfer;
 621         if (rfer_cmpr)
 622                 bq->rfer_cmpr = rfer_cmpr;
 623         if (excl)
 624                 bq->excl = excl;
 625         if (excl_cmpr)
 626                 bq->excl_cmpr = excl_cmpr;
 627         if (flags)
 628                 bq->flags = flags;
 629         if (max_rfer)
 630                 bq->max_rfer = max_rfer;
 631         if (max_excl)
 632                 bq->max_excl = max_excl;
 633         if (rsv_rfer)
 634                 bq->rsv_rfer = rsv_rfer;
 635         if (parent && child) {
 636                 list = malloc(sizeof(*list));
 637                 if (!list) {
 638                         fprintf(stderr, "memory allocation failed\n");
 639                         exit(1);
 640                 }
 641                 list->qgroup = parent;
 642                 list->member = child;
 643                 list_add_tail(&list->next_qgroup, &child->qgroups);
 644                 list_add_tail(&list->next_member, &parent->members);
 645         }
 646         ret = qgroup_tree_insert(qgroup_lookup, bq);
 647         if (ret) {
 648                 printf("failed to insert tree %llu\n",
 649                        bq->qgroupid);
 650                 exit(1);
 651         }
 652         return ret;
 653 }
 654
 655 void __free_btrfs_qgroup(struct btrfs_qgroup *bq)
 656 {
 657         struct btrfs_qgroup_list *list;
 658         while (!list_empty(&bq->qgroups)) {
 659                 list = list_entry((&bq->qgroups)->next,
 660                                   struct btrfs_qgroup_list,
 661                                   next_qgroup);
 662                 list_del(&list->next_qgroup);
 663                 list_del(&list->next_member);
 664                 free(list);
 665         }
 666         while (!list_empty(&bq->members)) {
 667                 list = list_entry((&bq->members)->next,
 668                                   struct btrfs_qgroup_list,
 669                                   next_member);
 670                 list_del(&list->next_qgroup);
 671                 list_del(&list->next_member);
 672                 free(list);
 673         }
 674         free(bq);
 675 }
 676
 677 void __free_all_qgroups(struct qgroup_lookup *root_tree)
 678 {
 679         struct btrfs_qgroup *entry;
 680         struct rb_node *n;
 681
 682         n = rb_first(&root_tree->root);
 683         while (n) {
 684                 entry = rb_entry(n, struct btrfs_qgroup, rb_node);
 685                 rb_erase(n, &root_tree->root);
 686                 __free_btrfs_qgroup(entry);
 687
 688                 n = rb_first(&root_tree->root);
 689         }
 690 }
 691
 692 static int filter_all_parent_insert(struct qgroup_lookup *sort_tree,
 693                                     struct btrfs_qgroup *bq)
 694 {
 695         struct rb_node **p = &sort_tree->root.rb_node;
 696         struct rb_node *parent = NULL;
 697         struct btrfs_qgroup *curr;
 698         int ret;
 699
 700         while (*p) {
 701                 parent = *p;
 702                 curr = rb_entry(parent, struct btrfs_qgroup, all_parent_node);
 703
 704                 ret = comp_entry_with_qgroupid(bq, curr, 0);
 705                 if (ret < 0)
 706                         p = &(*p)->rb_left;
 707                 else if (ret > 0)
 708                         p = &(*p)->rb_right;
 709                 else
 710                         return -EEXIST;
 711         }
 712         rb_link_node(&bq->all_parent_node, parent, p);
 713         rb_insert_color(&bq->all_parent_node, &sort_tree->root);
 714         return 0;
 715 }
 716
 717 static int filter_by_parent(struct btrfs_qgroup *bq, u64 data)
 718 {
 719         struct btrfs_qgroup *qgroup =
 720                 (struct btrfs_qgroup *)(unsigned long)data;
 721
 722         if (data == 0)
 723                 return 0;
 724         if (qgroup->qgroupid == bq->qgroupid)
 725                 return 1;
 726         return 0;
 727 }
 728
 729 static int filter_by_all_parent(struct btrfs_qgroup *bq, u64 data)
 730 {
 731         struct qgroup_lookup lookup;
 732         struct qgroup_lookup *ql = &lookup;
 733         struct btrfs_qgroup_list *list;
 734         struct rb_node *n;
 735         struct btrfs_qgroup *qgroup =
 736                          (struct btrfs_qgroup *)(unsigned long)data;
 737
 738         if (data == 0)
 739                 return 0;
 740         if (bq->qgroupid == qgroup->qgroupid)
 741                 return 1;
 742
 743         qgroup_lookup_init(ql);
 744         filter_all_parent_insert(ql, qgroup);
 745         n = rb_first(&ql->root);
 746         while (n) {
 747                 qgroup = rb_entry(n, struct btrfs_qgroup, all_parent_node);
 748                 if (!list_empty(&qgroup->qgroups)) {
 749                         list_for_each_entry(list, &qgroup->qgroups,
 750                                             next_qgroup) {
 751                                 if ((list->qgroup)->qgroupid == bq->qgroupid)
 752                                         return 1;
 753                                 filter_all_parent_insert(ql, list->qgroup);
 754                         }
 755                 }
 756                 rb_erase(n, &ql->root);
 757                 n = rb_first(&ql->root);
 758         }
 759         return 0;
 760 }
 761
 762 static btrfs_qgroup_filter_func all_filter_funcs[] = {
 763         [BTRFS_QGROUP_FILTER_PARENT]            = filter_by_parent,
 764         [BTRFS_QGROUP_FILTER_ALL_PARENT]        = filter_by_all_parent,
 765 };
 766
 767 struct btrfs_qgroup_filter_set *btrfs_qgroup_alloc_filter_set(void)
 768 {
 769         struct btrfs_qgroup_filter_set *set;
 770         int size;
 771
 772         size = sizeof(struct btrfs_qgroup_filter_set) +
 773                BTRFS_QGROUP_NFILTERS_INCREASE *
 774                sizeof(struct btrfs_qgroup_filter);
 775         set = malloc(size);
 776         if (!set) {
 777                 fprintf(stderr, "memory allocation failed\n");
 778                 exit(1);
 779         }
 780         memset(set, 0, size);
 781         set->total = BTRFS_QGROUP_NFILTERS_INCREASE;
 782
 783         return set;
 784 }
 785
 786 void btrfs_qgroup_free_filter_set(struct btrfs_qgroup_filter_set *filter_set)
 787 {
 788         free(filter_set);
 789 }
 790
 791 int btrfs_qgroup_setup_filter(struct btrfs_qgroup_filter_set **filter_set,
 792                               enum btrfs_qgroup_filter_enum filter, u64 data)
 793 {
 794         struct btrfs_qgroup_filter_set *set = *filter_set;
 795         int size;
 796
 797         BUG_ON(!set);
 798         BUG_ON(filter >= BTRFS_QGROUP_FILTER_MAX);
 799         BUG_ON(set->nfilters > set->total);
 800
 801         if (set->nfilters == set->total) {
 802                 size = set->total + BTRFS_QGROUP_NFILTERS_INCREASE;
 803                 size = sizeof(*set) + size * sizeof(struct btrfs_qgroup_filter);
 804
 805                 set = realloc(set, size);
 806                 if (!set) {
 807                         fprintf(stderr, "memory allocation failed\n");
 808                         exit(1);
 809                 }
 810                 memset(&set->filters[set->total], 0,
 811                        BTRFS_QGROUP_NFILTERS_INCREASE *
 812                        sizeof(struct btrfs_qgroup_filter));
 813                 set->total += BTRFS_QGROUP_NFILTERS_INCREASE;
 814                 *filter_set = set;
 815         }
 816         BUG_ON(set->filters[set->nfilters].filter_func);
 817         set->filters[set->nfilters].filter_func = all_filter_funcs[filter];
 818         set->filters[set->nfilters].data = data;
 819         set->nfilters++;
 820         return 0;
 821 }
 822
 823 static int filter_qgroup(struct btrfs_qgroup *bq,
 824                          struct btrfs_qgroup_filter_set *set)
 825 {
 826         int i, ret;
 827
 828         if (!set || !set->nfilters)
 829                 return 1;
 830         for (i = 0; i < set->nfilters; i++) {
 831                 if (!set->filters[i].filter_func)
 832                         break;
 833                 ret = set->filters[i].filter_func(bq, set->filters[i].data);
 834                 if (!ret)
 835                         return 0;
 836         }
 837         return 1;
 838 }
 839
 840 static void pre_process_filter_set(struct qgroup_lookup *lookup,
 841                                    struct btrfs_qgroup_filter_set *set)
 842 {
 843         int i;
 844         struct btrfs_qgroup *qgroup_for_filter = NULL;
 845
 846         for (i = 0; i < set->nfilters; i++) {
 847
 848                 if (set->filters[i].filter_func == filter_by_all_parent
 849                     || set->filters[i].filter_func == filter_by_parent) {
 850                         qgroup_for_filter = qgroup_tree_search(lookup,
 851                                             set->filters[i].data);
 852                         set->filters[i].data =
 853                                  (u64)(unsigned long)qgroup_for_filter;
 854                 }
 855         }
 856 }
 857
 858 static int sort_tree_insert(struct qgroup_lookup *sort_tree,
 859                             struct btrfs_qgroup *bq,
 860                             struct btrfs_qgroup_comparer_set *comp_set)
 861 {
 862         struct rb_node **p = &sort_tree->root.rb_node;
 863         struct rb_node *parent = NULL;
 864         struct btrfs_qgroup *curr;
 865         int ret;
 866
 867         while (*p) {
 868                 parent = *p;
 869                 curr = rb_entry(parent, struct btrfs_qgroup, sort_node);
 870
 871                 ret = sort_comp(bq, curr, comp_set);
 872                 if (ret < 0)
 873                         p = &(*p)->rb_left;
 874                 else if (ret > 0)
 875                         p = &(*p)->rb_right;
 876                 else
 877                         return -EEXIST;
 878         }
 879         rb_link_node(&bq->sort_node, parent, p);
 880         rb_insert_color(&bq->sort_node, &sort_tree->root);
 881         return 0;
 882 }
 883
 884 static void __update_columns_max_len(struct btrfs_qgroup *bq,
 885                                      enum btrfs_qgroup_column_enum column)
 886 {
 887         BUG_ON(column >= BTRFS_QGROUP_ALL || column < 0);
 888         struct btrfs_qgroup_list *list = NULL;
 889         char tmp[100];
 890         int len;
 891
 892         switch (column) {
 893
 894         case BTRFS_QGROUP_QGROUPID:
 895                 sprintf(tmp, "%llu/%llu", (bq->qgroupid >> 48),
 896                         bq->qgroupid & ((1ll << 48) - 1));
 897                 len = strlen(tmp);
 898                 if (btrfs_qgroup_columns[column].max_len < len)
 899                         btrfs_qgroup_columns[column].max_len = len;
 900                 break;
 901         case BTRFS_QGROUP_RFER:
 902                 sprintf(tmp, "%llu", bq->rfer);
 903                 len = strlen(tmp);
 904                 if (btrfs_qgroup_columns[column].max_len < len)
 905                         btrfs_qgroup_columns[column].max_len = len;
 906                 break;
 907         case BTRFS_QGROUP_EXCL:
 908                 sprintf(tmp, "%llu", bq->excl);
 909                 len = strlen(tmp);
 910                 if (btrfs_qgroup_columns[column].max_len < len)
 911                         btrfs_qgroup_columns[column].max_len = len;
 912                 break;
 913         case BTRFS_QGROUP_MAX_RFER:
 914                 sprintf(tmp, "%llu", bq->max_rfer);
 915                 len = strlen(tmp);
 916                 if (btrfs_qgroup_columns[column].max_len < len)
 917                         btrfs_qgroup_columns[column].max_len = len;
 918                 break;
 919         case BTRFS_QGROUP_MAX_EXCL:
 920                 sprintf(tmp, "%llu", bq->max_excl);
 921                 len = strlen(tmp);
 922                 if (btrfs_qgroup_columns[column].max_len < len)
 923                         btrfs_qgroup_columns[column].max_len = len;
 924                 break;
 925         case BTRFS_QGROUP_PARENT:
 926                 len = 0;
 927                 list_for_each_entry(list, &bq->qgroups, next_qgroup) {
 928                         len += sprintf(tmp, "%llu/%llu",
 929                                 (list->qgroup)->qgroupid >> 48,
 930                                 ((1ll << 48) - 1) & (list->qgroup)->qgroupid);
 931                         if (!list_is_last(&list->next_qgroup, &bq->qgroups))
 932                                 len += 1;
 933                 }
 934                 if (btrfs_qgroup_columns[column].max_len < len)
 935                         btrfs_qgroup_columns[column].max_len = len;
 936                 break;
 937         case BTRFS_QGROUP_CHILD:
 938                 len = 0;
 939                 list_for_each_entry(list, &bq->members, next_member) {
 940                         len += sprintf(tmp, "%llu/%llu",
 941                                 (list->member)->qgroupid >> 48,
 942                                 ((1ll << 48) - 1) & (list->member)->qgroupid);
 943                         if (!list_is_last(&list->next_member, &bq->members))
 944                                 len += 1;
 945                 }
 946                 if (btrfs_qgroup_columns[column].max_len < len)
 947                         btrfs_qgroup_columns[column].max_len = len;
 948                 break;
 949         default:
 950                 break;
 951         }
 952
 953 }
 954
 955 static void update_columns_max_len(struct btrfs_qgroup *bq)
 956 {
 957         int i;
 958
 959         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 960                 if (!btrfs_qgroup_columns[i].need_print)
 961                         continue;
 962                 __update_columns_max_len(bq, i);
 963         }
 964 }
 965
 966 static void __filter_and_sort_qgroups(struct qgroup_lookup *all_qgroups,
 967                                  struct qgroup_lookup *sort_tree,
 968                                  struct btrfs_qgroup_filter_set *filter_set,
 969                                  struct btrfs_qgroup_comparer_set *comp_set)
 970 {
 971         struct rb_node *n;
 972         struct btrfs_qgroup *entry;
 973         int ret;
 974
 975         qgroup_lookup_init(sort_tree);
 976         pre_process_filter_set(all_qgroups, filter_set);
 977
 978         n = rb_last(&all_qgroups->root);
 979         while (n) {
 980                 entry = rb_entry(n, struct btrfs_qgroup, rb_node);
 981
 982                 ret = filter_qgroup(entry, filter_set);
 983                 if (ret) {
 984                         sort_tree_insert(sort_tree, entry, comp_set);
 985
 986                         update_columns_max_len(entry);
 987                 }
 988                 n = rb_prev(n);
 989         }
 990 }
 991 static int __qgroups_search(int fd, struct qgroup_lookup *qgroup_lookup)
 992 {
 993         int ret;
 994         struct btrfs_ioctl_search_args args;
 995         struct btrfs_ioctl_search_key *sk = &args.key;
 996         struct btrfs_ioctl_search_header *sh;
 997         unsigned long off = 0;
 998         unsigned int i;
 999         int e;
1000         struct btrfs_qgroup_info_item *info;
1001         struct btrfs_qgroup_limit_item *limit;
1002         struct btrfs_qgroup *bq;
1003         struct btrfs_qgroup *bq1;
1004         u64 a1;
1005         u64 a2;
1006         u64 a3;
1007         u64 a4;
1008         u64 a5;
1009
1010         memset(&args, 0, sizeof(args));
1011
1012         sk->tree_id = BTRFS_QUOTA_TREE_OBJECTID;
1013         sk->max_type = BTRFS_QGROUP_RELATION_KEY;
1014         sk->min_type = BTRFS_QGROUP_INFO_KEY;
1015         sk->max_objectid = (u64)-1;
1016         sk->max_offset = (u64)-1;
1017         sk->max_transid = (u64)-1;
1018         sk->nr_items = 4096;
1019
1020         qgroup_lookup_init(qgroup_lookup);
1021
1022         while (1) {
1023                 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
1024                 e = errno;
1025                 if (ret < 0) {
1026                         fprintf(stderr,
1027                                 "ERROR: can't perform the search - %s\n",
1028                                 strerror(e));
1029                         return ret;
1030                 }
1031                 /* the ioctl returns the number of item it found in nr_items */
1032                 if (sk->nr_items == 0)
1033                         break;
1034
1035                 off = 0;
1036                 /*
1037                  * for each item, pull the key out of the header and then
1038                  * read the root_ref item it contains
1039                  */
1040                 for (i = 0; i < sk->nr_items; i++) {
1041                         sh = (struct btrfs_ioctl_search_header *)(args.buf +
1042                                                                   off);
1043                         off += sizeof(*sh);
1044
1045                         if (sh->type == BTRFS_QGROUP_INFO_KEY) {
1046                                 info = (struct btrfs_qgroup_info_item *)
1047                                        (args.buf + off);
1048                                 a1 = btrfs_stack_qgroup_info_generation(info);
1049                                 a2 = btrfs_stack_qgroup_info_referenced(info);
1050                                 a3 =
1051                                   btrfs_stack_qgroup_info_referenced_compressed
1052                                   (info);
1053                                 a4 = btrfs_stack_qgroup_info_exclusive(info);
1054                                 a5 =
1055                                   btrfs_stack_qgroup_info_exclusive_compressed
1056                                   (info);
1057                                 add_qgroup(qgroup_lookup, sh->offset, a1, a2,
1058                                            a3, a4, a5, 0, 0, 0, 0, 0, 0, 0);
1059                         } else if (sh->type == BTRFS_QGROUP_LIMIT_KEY) {
1060                                 limit = (struct btrfs_qgroup_limit_item *)
1061                                     (args.buf + off);
1062
1063                                 a1 = btrfs_stack_qgroup_limit_flags(limit);
1064                                 a2 = btrfs_stack_qgroup_limit_max_referenced
1065                                      (limit);
1066                                 a3 = btrfs_stack_qgroup_limit_max_exclusive
1067                                      (limit);
1068                                 a4 = btrfs_stack_qgroup_limit_rsv_referenced
1069                                      (limit);
1070                                 a5 = btrfs_stack_qgroup_limit_rsv_exclusive
1071                                      (limit);
1072                                 add_qgroup(qgroup_lookup, sh->offset, 0, 0,
1073                                            0, 0, 0, a1, a2, a3, a4, a5, 0, 0);
1074                         } else if (sh->type == BTRFS_QGROUP_RELATION_KEY) {
1075                                 if (sh->offset < sh->objectid)
1076                                         goto skip;
1077                                 bq = qgroup_tree_search(qgroup_lookup,
1078                                                         sh->offset);
1079                                 if (!bq)
1080                                         goto skip;
1081                                 bq1 = qgroup_tree_search(qgroup_lookup,
1082                                                          sh->objectid);
1083                                 if (!bq1)
1084                                         goto skip;
1085                                 add_qgroup(qgroup_lookup, sh->offset, 0, 0,
1086                                            0, 0, 0, 0, 0, 0, 0, 0, bq, bq1);
1087                         } else
1088                                 goto done;
1089 skip:
1090                         off += sh->len;
1091
1092                         /*
1093                          * record the mins in sk so we can make sure the
1094                          * next search doesn't repeat this root
1095                          */
1096                         sk->min_type = sh->type;
1097                         sk->min_offset = sh->offset;
1098                         sk->min_objectid = sh->objectid;
1099                 }
1100                 sk->nr_items = 4096;
1101                 /*
1102                  * this iteration is done, step forward one qgroup for the next
1103                  * ioctl
1104                  */
1105                 if (sk->min_offset < (u64)-1)
1106                         sk->min_offset++;
1107                 else
1108                         break;
1109         }
1110
1111 done:
1112         return ret;
1113 }
1114
1115 static void print_all_qgroups(struct qgroup_lookup *qgroup_lookup)
1116 {
1117
1118         struct rb_node *n;
1119         struct btrfs_qgroup *entry;
1120
1121         print_table_head();
1122
1123         n = rb_first(&qgroup_lookup->root);
1124         while (n) {
1125                 entry = rb_entry(n, struct btrfs_qgroup, sort_node);
1126                 print_single_qgroup_table(entry);
1127                 n = rb_next(n);
1128         }
1129 }
1130
1131 int btrfs_show_qgroups(int fd,
1132                        struct btrfs_qgroup_filter_set *filter_set,
1133                        struct btrfs_qgroup_comparer_set *comp_set)
1134 {
1135
1136         struct qgroup_lookup qgroup_lookup;
1137         struct qgroup_lookup sort_tree;
1138         int ret;
1139
1140         ret = __qgroups_search(fd, &qgroup_lookup);
1141         if (ret)
1142                 return ret;
1143         __filter_and_sort_qgroups(&qgroup_lookup, &sort_tree,
1144                                   filter_set, comp_set);
1145         print_all_qgroups(&sort_tree);
1146
1147         __free_all_qgroups(&qgroup_lookup);
1148         btrfs_qgroup_free_filter_set(filter_set);
1149         return ret;
1150 }
1151
1152 u64 btrfs_get_path_rootid(int fd)
1153 {
1154         int  ret;
1155         struct btrfs_ioctl_ino_lookup_args args;
1156
1157         memset(&args, 0, sizeof(args));
1158         args.objectid = BTRFS_FIRST_FREE_OBJECTID;
1159
1160         ret = ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args);
1161         if (ret < 0) {
1162                 fprintf(stderr,
1163                         "ERROR: can't perform the search -%s\n",
1164                         strerror(errno));
1165                 return ret;
1166         }
1167         return args.treeid;
1168 }
1169
1170 int btrfs_qgroup_parse_sort_string(char *opt_arg,
1171                                    struct btrfs_qgroup_comparer_set **comps)
1172 {
1173         int order;
1174         int flag;
1175         char *p;
1176         char **ptr_argv;
1177         int what_to_sort;
1178
1179         while ((p = strtok(opt_arg, ",")) != NULL) {
1180                 flag = 0;
1181                 ptr_argv = all_sort_items;
1182
1183                 while (*ptr_argv) {
1184                         if (strcmp(*ptr_argv, p) == 0) {
1185                                 flag = 1;
1186                                 break;
1187                         } else {
1188                                 p++;
1189                                 if (strcmp(*ptr_argv, p) == 0) {
1190                                         flag = 1;
1191                                         p--;
1192                                         break;
1193                                 }
1194                                 p--;
1195                         }
1196                         ptr_argv++;
1197                 }
1198
1199                 if (flag == 0)
1200                         return -1;
1201
1202                 else {
1203                         if (*p == '+') {
1204                                 order = 0;
1205                                 p++;
1206                         } else if (*p == '-') {
1207                                 order = 1;
1208                                 p++;
1209                         } else
1210                                 order = 0;
1211
1212                         what_to_sort = btrfs_qgroup_get_sort_item(p);
1213                         if (what_to_sort < 0)
1214                                 return -1;
1215                         btrfs_qgroup_setup_comparer(comps, what_to_sort, order);
1216                 }
1217                 opt_arg = NULL;
1218         }
1219
1220         return 0;
1221 }
1222
1223 u64 parse_qgroupid(char *p)
1224 {
1225         char *s = strchr(p, '/');
1226         char *ptr_src_end = p + strlen(p);
1227         char *ptr_parse_end = NULL;
1228         u64 level;
1229         u64 id;
1230
1231         if (!s) {
1232                 id = strtoull(p, &ptr_parse_end, 10);
1233                 if (ptr_parse_end != ptr_src_end)
1234                         goto err;
1235                 return id;
1236         }
1237         level = strtoull(p, &ptr_parse_end, 10);
1238         if (ptr_parse_end != s)
1239                 goto err;
1240
1241         id = strtoull(s+1, &ptr_parse_end, 10);
1242         if (ptr_parse_end != ptr_src_end)
1243                 goto  err;
1244
1245         return (level << 48) | id;
1246 err:
1247         fprintf(stderr, "ERROR:invalid qgroupid\n");
1248         exit(-1);
1249 }
1250
1251 int qgroup_inherit_size(struct btrfs_qgroup_inherit *p)
1252 {
1253         return sizeof(*p) + sizeof(p->qgroups[0]) *
1254                             (p->num_qgroups + 2 * p->num_ref_copies +
1255                              2 * p->num_excl_copies);
1256 }
1257
1258 static int
1259 qgroup_inherit_realloc(struct btrfs_qgroup_inherit **inherit, int n, int pos)
1260 {
1261         struct btrfs_qgroup_inherit *out;
1262         int nitems = 0;
1263
1264         if (*inherit) {
1265                 nitems = (*inherit)->num_qgroups +
1266                          (*inherit)->num_ref_copies +
1267                          (*inherit)->num_excl_copies;
1268         }
1269
1270         out = calloc(sizeof(*out) + sizeof(out->qgroups[0]) * (nitems + n), 1);
1271         if (out == NULL) {
1272                 fprintf(stderr, "ERROR: Not enough memory\n");
1273                 return 13;
1274         }
1275
1276         if (*inherit) {
1277                 struct btrfs_qgroup_inherit *i = *inherit;
1278                 int s = sizeof(out->qgroups[0]);
1279
1280                 out->num_qgroups = i->num_qgroups;
1281                 out->num_ref_copies = i->num_ref_copies;
1282                 out->num_excl_copies = i->num_excl_copies;
1283                 memcpy(out->qgroups, i->qgroups, pos * s);
1284                 memcpy(out->qgroups + pos + n, i->qgroups + pos,
1285                        (nitems - pos) * s);
1286         }
1287         free(*inherit);
1288         *inherit = out;
1289
1290         return 0;
1291 }
1292
1293 int qgroup_inherit_add_group(struct btrfs_qgroup_inherit **inherit, char *arg)
1294 {
1295         int ret;
1296         u64 qgroupid = parse_qgroupid(arg);
1297         int pos = 0;
1298
1299         if (qgroupid == 0) {
1300                 fprintf(stderr, "ERROR: bad qgroup specification\n");
1301                 return 12;
1302         }
1303
1304         if (*inherit)
1305                 pos = (*inherit)->num_qgroups;
1306         ret = qgroup_inherit_realloc(inherit, 1, pos);
1307         if (ret)
1308                 return ret;
1309
1310         (*inherit)->qgroups[(*inherit)->num_qgroups++] = qgroupid;
1311
1312         return 0;
1313 }
1314
1315 int qgroup_inherit_add_copy(struct btrfs_qgroup_inherit **inherit, char *arg,
1316                             int type)
1317 {
1318         int ret;
1319         u64 qgroup_src;
1320         u64 qgroup_dst;
1321         char *p;
1322         int pos = 0;
1323
1324         p = strchr(arg, ':');
1325         if (!p) {
1326 bad:
1327                 fprintf(stderr, "ERROR: bad copy specification\n");
1328                 return 12;
1329         }
1330         *p = 0;
1331         qgroup_src = parse_qgroupid(arg);
1332         qgroup_dst = parse_qgroupid(p + 1);
1333         *p = ':';
1334
1335         if (!qgroup_src || !qgroup_dst)
1336                 goto bad;
1337
1338         if (*inherit)
1339                 pos = (*inherit)->num_qgroups +
1340                       (*inherit)->num_ref_copies * 2 * type;
1341
1342         ret = qgroup_inherit_realloc(inherit, 2, pos);
1343         if (ret)
1344                 return ret;
1345
1346         (*inherit)->qgroups[pos++] = qgroup_src;
1347         (*inherit)->qgroups[pos++] = qgroup_dst;
1348
1349         if (!type)
1350                 ++(*inherit)->num_ref_copies;
1351         else
1352                 ++(*inherit)->num_excl_copies;
1353
1354         return 0;
1355 }