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 #include "utils.h"
  24 #include <errno.h>
  25
  26 #define BTRFS_QGROUP_NFILTERS_INCREASE (2 * BTRFS_QGROUP_FILTER_MAX)
  27 #define BTRFS_QGROUP_NCOMPS_INCREASE (2 * BTRFS_QGROUP_COMP_MAX)
  28
  29 struct qgroup_lookup {
  30         struct rb_root root;
  31 };
  32
  33 struct btrfs_qgroup {
  34         struct rb_node rb_node;
  35         struct rb_node sort_node;
  36         /*
  37          *all_parent_node is used to
  38          *filter a qgroup's all parent
  39          */
  40         struct rb_node all_parent_node;
  41         u64 qgroupid;
  42
  43         /*
  44          * info_item
  45          */
  46         u64 generation;
  47         u64 rfer;       /*referenced*/
  48         u64 rfer_cmpr;  /*referenced compressed*/
  49         u64 excl;       /*exclusive*/
  50         u64 excl_cmpr;  /*exclusive compressed*/
  51
  52         /*
  53          *limit_item
  54          */
  55         u64 flags;      /*which limits are set*/
  56         u64 max_rfer;
  57         u64 max_excl;
  58         u64 rsv_rfer;
  59         u64 rsv_excl;
  60
  61         /*qgroups this group is member of*/
  62         struct list_head qgroups;
  63         /*qgroups that are members of this group*/
  64         struct list_head members;
  65 };
  66
  67 /*
  68  * glue structure to represent the relations
  69  * between qgroups
  70  */
  71 struct btrfs_qgroup_list {
  72         struct list_head next_qgroup;
  73         struct list_head next_member;
  74         struct btrfs_qgroup *qgroup;
  75         struct btrfs_qgroup *member;
  76 };
  77
  78 /*
  79  * qgroupid,rfer,excl default to set
  80  */
  81 static struct {
  82         char *name;
  83         char *column_name;
  84         int need_print;
  85         unsigned unit_mode;
  86         int max_len;
  87 } btrfs_qgroup_columns[] = {
  88         {
  89                 .name           = "qgroupid",
  90                 .column_name    = "Qgroupid",
  91                 .need_print     = 1,
  92                 .unit_mode      = 0,
  93                 .max_len        = 8,
  94         },
  95         {
  96                 .name           = "rfer",
  97                 .column_name    = "Rfer",
  98                 .need_print     = 1,
  99                 .unit_mode      = UNITS_DEFAULT,
 100                 .max_len        = 12,
 101         },
 102         {
 103                 .name           = "excl",
 104                 .column_name    = "Excl",
 105                 .need_print     = 1,
 106                 .unit_mode      = UNITS_DEFAULT,
 107                 .max_len        = 12,
 108         },
 109         {       .name           = "max_rfer",
 110                 .column_name    = "Max_rfer",
 111                 .need_print     = 0,
 112                 .unit_mode      = UNITS_DEFAULT,
 113                 .max_len        = 12,
 114         },
 115         {
 116                 .name           = "max_excl",
 117                 .column_name    = "Max_excl",
 118                 .need_print     = 0,
 119                 .unit_mode      = UNITS_DEFAULT,
 120                 .max_len        = 12,
 121         },
 122         {
 123                 .name           = "parent",
 124                 .column_name    = "Parent",
 125                 .need_print     = 0,
 126                 .unit_mode      = 0,
 127                 .max_len        = 7,
 128         },
 129         {
 130                 .name           = "child",
 131                 .column_name    = "Child",
 132                 .need_print     = 0,
 133                 .unit_mode      = 0,
 134                 .max_len        = 5,
 135         },
 136         {
 137                 .name           = NULL,
 138                 .column_name    = NULL,
 139                 .need_print     = 0,
 140                 .unit_mode      = 0,
 141         },
 142 };
 143
 144 static btrfs_qgroup_filter_func all_filter_funcs[];
 145 static btrfs_qgroup_comp_func all_comp_funcs[];
 146
 147 void btrfs_qgroup_setup_print_column(enum btrfs_qgroup_column_enum column)
 148 {
 149         int i;
 150
 151         ASSERT(0 <= column && column <= BTRFS_QGROUP_ALL);
 152
 153         if (column < BTRFS_QGROUP_ALL) {
 154                 btrfs_qgroup_columns[column].need_print = 1;
 155                 return;
 156         }
 157         for (i = 0; i < BTRFS_QGROUP_ALL; i++)
 158                 btrfs_qgroup_columns[i].need_print = 1;
 159 }
 160
 161 void btrfs_qgroup_setup_units(unsigned unit_mode)
 162 {
 163         btrfs_qgroup_columns[BTRFS_QGROUP_RFER].unit_mode = unit_mode;
 164         btrfs_qgroup_columns[BTRFS_QGROUP_EXCL].unit_mode = unit_mode;
 165         btrfs_qgroup_columns[BTRFS_QGROUP_MAX_RFER].unit_mode = unit_mode;
 166         btrfs_qgroup_columns[BTRFS_QGROUP_MAX_EXCL].unit_mode = unit_mode;
 167 }
 168
 169 static int print_parent_column(struct btrfs_qgroup *qgroup)
 170 {
 171         struct btrfs_qgroup_list *list = NULL;
 172         int len = 0;
 173
 174         list_for_each_entry(list, &qgroup->qgroups, next_qgroup) {
 175                 len += printf("%llu/%llu",
 176                               btrfs_qgroup_level(list->qgroup->qgroupid),
 177                               btrfs_qgroup_subvid(list->qgroup->qgroupid));
 178                 if (!list_is_last(&list->next_qgroup, &qgroup->qgroups))
 179                         len += printf(",");
 180         }
 181         if (list_empty(&qgroup->qgroups))
 182                 len += printf("---");
 183
 184         return len;
 185 }
 186
 187 static int print_child_column(struct btrfs_qgroup *qgroup)
 188 {
 189         struct btrfs_qgroup_list *list = NULL;
 190         int len = 0;
 191
 192         list_for_each_entry(list, &qgroup->members, next_member) {
 193                 len += printf("%llu/%llu",
 194                               btrfs_qgroup_level(list->member->qgroupid),
 195                               btrfs_qgroup_subvid(list->member->qgroupid));
 196                 if (!list_is_last(&list->next_member, &qgroup->members))
 197                         len += printf(",");
 198         }
 199         if (list_empty(&qgroup->members))
 200                 len += printf("---");
 201
 202         return len;
 203 }
 204
 205 static void print_qgroup_column_add_blank(enum btrfs_qgroup_column_enum column,
 206                                           int len)
 207 {
 208         len = btrfs_qgroup_columns[column].max_len - len;
 209         while (len--)
 210                 printf(" ");
 211 }
 212
 213 static void print_qgroup_column(struct btrfs_qgroup *qgroup,
 214                                 enum btrfs_qgroup_column_enum column)
 215 {
 216         int len;
 217         int unit_mode = btrfs_qgroup_columns[column].unit_mode;
 218         int max_len = btrfs_qgroup_columns[column].max_len;
 219
 220         ASSERT(0 <= column && column < BTRFS_QGROUP_ALL);
 221
 222         switch (column) {
 223
 224         case BTRFS_QGROUP_QGROUPID:
 225                 len = printf("%llu/%llu",
 226                              btrfs_qgroup_level(qgroup->qgroupid),
 227                              btrfs_qgroup_subvid(qgroup->qgroupid));
 228                 print_qgroup_column_add_blank(BTRFS_QGROUP_QGROUPID, len);
 229                 break;
 230         case BTRFS_QGROUP_RFER:
 231                 len = printf("%*s", max_len, pretty_size_mode(qgroup->rfer, unit_mode));
 232                 break;
 233         case BTRFS_QGROUP_EXCL:
 234                 len = printf("%*s", max_len, pretty_size_mode(qgroup->excl, unit_mode));
 235                 break;
 236         case BTRFS_QGROUP_PARENT:
 237                 len = print_parent_column(qgroup);
 238                 print_qgroup_column_add_blank(BTRFS_QGROUP_PARENT, len);
 239                 break;
 240         case BTRFS_QGROUP_MAX_RFER:
 241                 if (qgroup->flags & BTRFS_QGROUP_LIMIT_MAX_RFER)
 242                         len = printf("%*s", max_len, pretty_size_mode(qgroup->max_rfer, unit_mode));
 243                 else
 244                         len = printf("%*s", max_len, "none");
 245                 break;
 246         case BTRFS_QGROUP_MAX_EXCL:
 247                 if (qgroup->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL)
 248                         len = printf("%*s", max_len, pretty_size_mode(qgroup->max_excl, unit_mode));
 249                 else
 250                         len = printf("%*s", max_len, "none");
 251                 break;
 252         case BTRFS_QGROUP_CHILD:
 253                 len = print_child_column(qgroup);
 254                 print_qgroup_column_add_blank(BTRFS_QGROUP_CHILD, len);
 255                 break;
 256         default:
 257                 break;
 258         }
 259 }
 260
 261 static void print_single_qgroup_table(struct btrfs_qgroup *qgroup)
 262 {
 263         int i;
 264
 265         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 266                 if (!btrfs_qgroup_columns[i].need_print)
 267                         continue;
 268                 print_qgroup_column(qgroup, i);
 269
 270                 if (i != BTRFS_QGROUP_CHILD)
 271                         printf(" ");
 272         }
 273         printf("\n");
 274 }
 275
 276 static void print_table_head(void)
 277 {
 278         int i;
 279         int len;
 280         int max_len;
 281
 282         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 283                 max_len = btrfs_qgroup_columns[i].max_len;
 284                 if (!btrfs_qgroup_columns[i].need_print)
 285                         continue;
 286                 if ((i == BTRFS_QGROUP_QGROUPID) | (i == BTRFS_QGROUP_PARENT) |
 287                         (i == BTRFS_QGROUP_CHILD))
 288                         printf("%-*s", max_len, btrfs_qgroup_columns[i].name);
 289                 else
 290                         printf("%*s", max_len, btrfs_qgroup_columns[i].name);
 291                 printf(" ");
 292         }
 293         printf("\n");
 294         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 295                 max_len = btrfs_qgroup_columns[i].max_len;
 296                 if (!btrfs_qgroup_columns[i].need_print)
 297                         continue;
 298                 if ((i == BTRFS_QGROUP_QGROUPID) | (i == BTRFS_QGROUP_PARENT) |
 299                         (i == BTRFS_QGROUP_CHILD)) {
 300                         len = strlen(btrfs_qgroup_columns[i].name);
 301                         while (len--)
 302                                 printf("-");
 303                         len = max_len - strlen(btrfs_qgroup_columns[i].name);
 304                         while (len--)
 305                                 printf(" ");
 306                 } else {
 307                         len = max_len - strlen(btrfs_qgroup_columns[i].name);
 308                         while (len--)
 309                                 printf(" ");
 310                         len = strlen(btrfs_qgroup_columns[i].name);
 311                         while (len--)
 312                                 printf("-");
 313                 }
 314                 printf(" ");
 315         }
 316         printf("\n");
 317 }
 318
 319 static void qgroup_lookup_init(struct qgroup_lookup *tree)
 320 {
 321         tree->root.rb_node = NULL;
 322 }
 323
 324 static int comp_entry_with_qgroupid(struct btrfs_qgroup *entry1,
 325                                     struct btrfs_qgroup *entry2,
 326                                     int is_descending)
 327 {
 328
 329         int ret;
 330
 331         if (entry1->qgroupid > entry2->qgroupid)
 332                 ret = 1;
 333         else if (entry1->qgroupid < entry2->qgroupid)
 334                 ret = -1;
 335         else
 336                 ret = 0;
 337
 338         return is_descending ? -ret : ret;
 339 }
 340
 341 static int comp_entry_with_rfer(struct btrfs_qgroup *entry1,
 342                                 struct btrfs_qgroup *entry2,
 343                                 int is_descending)
 344 {
 345         int ret;
 346
 347         if (entry1->rfer > entry2->rfer)
 348                 ret = 1;
 349         else if (entry1->rfer < entry2->rfer)
 350                 ret = -1;
 351         else
 352                 ret = 0;
 353
 354         return is_descending ? -ret : ret;
 355 }
 356
 357 static int comp_entry_with_excl(struct btrfs_qgroup *entry1,
 358                                 struct btrfs_qgroup *entry2,
 359                                 int is_descending)
 360 {
 361         int ret;
 362
 363         if (entry1->excl > entry2->excl)
 364                 ret = 1;
 365         else if (entry1->excl < entry2->excl)
 366                 ret = -1;
 367         else
 368                 ret = 0;
 369
 370         return is_descending ? -ret : ret;
 371 }
 372
 373 static int comp_entry_with_max_rfer(struct btrfs_qgroup *entry1,
 374                                     struct btrfs_qgroup *entry2,
 375                                     int is_descending)
 376 {
 377         int ret;
 378
 379         if (entry1->max_rfer > entry2->max_rfer)
 380                 ret = 1;
 381         else if (entry1->max_rfer < entry2->max_rfer)
 382                 ret = -1;
 383         else
 384                 ret = 0;
 385
 386         return is_descending ? -ret : ret;
 387 }
 388
 389 static int comp_entry_with_max_excl(struct btrfs_qgroup *entry1,
 390                                     struct btrfs_qgroup *entry2,
 391                                     int is_descending)
 392 {
 393         int ret;
 394
 395         if (entry1->max_excl > entry2->max_excl)
 396                 ret = 1;
 397         else if (entry1->max_excl < entry2->max_excl)
 398                 ret = -1;
 399         else
 400                 ret = 0;
 401
 402         return is_descending ? -ret : ret;
 403 }
 404
 405 static btrfs_qgroup_comp_func all_comp_funcs[] = {
 406         [BTRFS_QGROUP_COMP_QGROUPID]    = comp_entry_with_qgroupid,
 407         [BTRFS_QGROUP_COMP_RFER]        = comp_entry_with_rfer,
 408         [BTRFS_QGROUP_COMP_EXCL]        = comp_entry_with_excl,
 409         [BTRFS_QGROUP_COMP_MAX_RFER]    = comp_entry_with_max_rfer,
 410         [BTRFS_QGROUP_COMP_MAX_EXCL]    = comp_entry_with_max_excl
 411 };
 412
 413 static char *all_sort_items[] = {
 414         [BTRFS_QGROUP_COMP_QGROUPID]    = "qgroupid",
 415         [BTRFS_QGROUP_COMP_RFER]        = "rfer",
 416         [BTRFS_QGROUP_COMP_EXCL]        = "excl",
 417         [BTRFS_QGROUP_COMP_MAX_RFER]    = "max_rfer",
 418         [BTRFS_QGROUP_COMP_MAX_EXCL]    = "max_excl",
 419         [BTRFS_QGROUP_COMP_MAX]         = NULL,
 420 };
 421
 422 static int  btrfs_qgroup_get_sort_item(char *sort_name)
 423 {
 424         int i;
 425
 426         for (i = 0; i < BTRFS_QGROUP_COMP_MAX; i++) {
 427                 if (strcmp(sort_name, all_sort_items[i]) == 0)
 428                         return i;
 429         }
 430         return -1;
 431 }
 432
 433 struct btrfs_qgroup_comparer_set *btrfs_qgroup_alloc_comparer_set(void)
 434 {
 435         struct btrfs_qgroup_comparer_set *set;
 436         int size;
 437         size = sizeof(struct btrfs_qgroup_comparer_set) +
 438                BTRFS_QGROUP_NCOMPS_INCREASE *
 439                sizeof(struct btrfs_qgroup_comparer);
 440         set = calloc(1, size);
 441         if (!set) {
 442                 error("memory allocation failed");
 443                 exit(1);
 444         }
 445
 446         set->total = BTRFS_QGROUP_NCOMPS_INCREASE;
 447
 448         return set;
 449 }
 450
 451 int btrfs_qgroup_setup_comparer(struct btrfs_qgroup_comparer_set  **comp_set,
 452                                 enum btrfs_qgroup_comp_enum comparer,
 453                                 int is_descending)
 454 {
 455         struct btrfs_qgroup_comparer_set *set = *comp_set;
 456         int size;
 457
 458         ASSERT(set != NULL);
 459         ASSERT(comparer < BTRFS_QGROUP_COMP_MAX);
 460         ASSERT(set->ncomps <= set->total);
 461
 462         if (set->ncomps == set->total) {
 463                 void *tmp;
 464
 465                 size = set->total + BTRFS_QGROUP_NCOMPS_INCREASE;
 466                 size = sizeof(*set) +
 467                        size * sizeof(struct btrfs_qgroup_comparer);
 468                 tmp = set;
 469                 set = realloc(set, size);
 470                 if (!set) {
 471                         error("memory allocation failed");
 472                         free(tmp);
 473                         exit(1);
 474                 }
 475
 476                 memset(&set->comps[set->total], 0,
 477                        BTRFS_QGROUP_NCOMPS_INCREASE *
 478                        sizeof(struct btrfs_qgroup_comparer));
 479                 set->total += BTRFS_QGROUP_NCOMPS_INCREASE;
 480                 *comp_set = set;
 481         }
 482
 483         ASSERT(set->comps[set->ncomps].comp_func == NULL);
 484
 485         set->comps[set->ncomps].comp_func = all_comp_funcs[comparer];
 486         set->comps[set->ncomps].is_descending = is_descending;
 487         set->ncomps++;
 488         return 0;
 489 }
 490
 491 static int sort_comp(struct btrfs_qgroup *entry1, struct btrfs_qgroup *entry2,
 492                      struct btrfs_qgroup_comparer_set *set)
 493 {
 494         int qgroupid_compared = 0;
 495         int i, ret = 0;
 496
 497         if (!set || !set->ncomps)
 498                 goto comp_qgroupid;
 499
 500         for (i = 0; i < set->ncomps; i++) {
 501                 if (!set->comps[i].comp_func)
 502                         break;
 503
 504                 ret = set->comps[i].comp_func(entry1, entry2,
 505                                               set->comps[i].is_descending);
 506                 if (ret)
 507                         return ret;
 508
 509                 if (set->comps[i].comp_func == comp_entry_with_qgroupid)
 510                         qgroupid_compared = 1;
 511         }
 512
 513         if (!qgroupid_compared) {
 514 comp_qgroupid:
 515                 ret = comp_entry_with_qgroupid(entry1, entry2, 0);
 516         }
 517
 518         return ret;
 519 }
 520
 521 /*
 522  * insert a new root into the tree.  returns the existing root entry
 523  * if one is already there.  qgroupid is used
 524  * as the key
 525  */
 526 static int qgroup_tree_insert(struct qgroup_lookup *root_tree,
 527                               struct btrfs_qgroup *ins)
 528 {
 529
 530         struct rb_node **p = &root_tree->root.rb_node;
 531         struct rb_node *parent = NULL;
 532         struct btrfs_qgroup *curr;
 533         int ret;
 534
 535         while (*p) {
 536                 parent = *p;
 537                 curr = rb_entry(parent, struct btrfs_qgroup, rb_node);
 538
 539                 ret = comp_entry_with_qgroupid(ins, curr, 0);
 540                 if (ret < 0)
 541                         p = &(*p)->rb_left;
 542                 else if (ret > 0)
 543                         p = &(*p)->rb_right;
 544                 else
 545                         return -EEXIST;
 546         }
 547         rb_link_node(&ins->rb_node, parent, p);
 548         rb_insert_color(&ins->rb_node, &root_tree->root);
 549         return 0;
 550 }
 551
 552 /*
 553  *find a given qgroupid in the tree. We return the smallest one,
 554  *rb_next can be used to move forward looking for more if required
 555  */
 556 static struct btrfs_qgroup *qgroup_tree_search(struct qgroup_lookup *root_tree,
 557                                                u64 qgroupid)
 558 {
 559         struct rb_node *n = root_tree->root.rb_node;
 560         struct btrfs_qgroup *entry;
 561         struct btrfs_qgroup tmp;
 562         int ret;
 563
 564         tmp.qgroupid = qgroupid;
 565
 566         while (n) {
 567                 entry = rb_entry(n, struct btrfs_qgroup, rb_node);
 568
 569                 ret = comp_entry_with_qgroupid(&tmp, entry, 0);
 570                 if (ret < 0)
 571                         n = n->rb_left;
 572                 else if (ret > 0)
 573                         n = n->rb_right;
 574                 else
 575                         return entry;
 576
 577         }
 578         return NULL;
 579 }
 580
 581 /*
 582  * Lookup or insert btrfs_qgroup into qgroup_lookup.
 583  *
 584  * Search a btrfs_qgroup with @qgroupid from the @qgroup_lookup. If not found,
 585  * initialize a btrfs_qgroup with the given qgroupid and insert it to the
 586  * @qgroup_lookup.
 587  *
 588  * Return the pointer to the btrfs_qgroup if found or if inserted successfully.
 589  * Return ERR_PTR if any error occurred.
 590  */
 591 static struct btrfs_qgroup *get_or_add_qgroup(
 592                 struct qgroup_lookup *qgroup_lookup, u64 qgroupid)
 593 {
 594         struct btrfs_qgroup *bq;
 595         int ret;
 596
 597         bq = qgroup_tree_search(qgroup_lookup, qgroupid);
 598         if (bq)
 599                 return bq;
 600
 601         bq = calloc(1, sizeof(*bq));
 602         if (!bq) {
 603                 error("memory allocation failed");
 604                 return ERR_PTR(-ENOMEM);
 605         }
 606
 607         bq->qgroupid = qgroupid;
 608         INIT_LIST_HEAD(&bq->qgroups);
 609         INIT_LIST_HEAD(&bq->members);
 610
 611         ret = qgroup_tree_insert(qgroup_lookup, bq);
 612         if (ret) {
 613                 error("failed to insert %llu into tree: %s",
 614                        (unsigned long long)bq->qgroupid, strerror(-ret));
 615                 free(bq);
 616                 return ERR_PTR(ret);
 617         }
 618
 619         return bq;
 620 }
 621
 622 static int update_qgroup_info(struct qgroup_lookup *qgroup_lookup, u64 qgroupid,
 623                               struct btrfs_qgroup_info_item *info)
 624 {
 625         struct btrfs_qgroup *bq;
 626
 627         bq = get_or_add_qgroup(qgroup_lookup, qgroupid);
 628         if (IS_ERR_OR_NULL(bq))
 629                 return PTR_ERR(bq);
 630
 631         bq->generation = btrfs_stack_qgroup_info_generation(info);
 632         bq->rfer = btrfs_stack_qgroup_info_referenced(info);
 633         bq->rfer_cmpr = btrfs_stack_qgroup_info_referenced_compressed(info);
 634         bq->excl = btrfs_stack_qgroup_info_exclusive(info);
 635         bq->excl_cmpr = btrfs_stack_qgroup_info_exclusive_compressed(info);
 636
 637         return 0;
 638 }
 639
 640 static int update_qgroup_limit(struct qgroup_lookup *qgroup_lookup,
 641                                u64 qgroupid,
 642                                struct btrfs_qgroup_limit_item *limit)
 643 {
 644         struct btrfs_qgroup *bq;
 645
 646         bq = get_or_add_qgroup(qgroup_lookup, qgroupid);
 647         if (IS_ERR_OR_NULL(bq))
 648                 return PTR_ERR(bq);
 649
 650         bq->flags = btrfs_stack_qgroup_limit_flags(limit);
 651         bq->max_rfer = btrfs_stack_qgroup_limit_max_referenced(limit);
 652         bq->max_excl = btrfs_stack_qgroup_limit_max_exclusive(limit);
 653         bq->rsv_rfer = btrfs_stack_qgroup_limit_rsv_referenced(limit);
 654         bq->rsv_excl = btrfs_stack_qgroup_limit_rsv_exclusive(limit);
 655
 656         return 0;
 657 }
 658
 659 static int update_qgroup_relation(struct qgroup_lookup *qgroup_lookup,
 660                                   u64 child_id, u64 parent_id)
 661 {
 662         struct btrfs_qgroup *child;
 663         struct btrfs_qgroup *parent;
 664         struct btrfs_qgroup_list *list;
 665
 666         child = qgroup_tree_search(qgroup_lookup, child_id);
 667         if (!child) {
 668                 error("cannot find the qgroup %llu/%llu",
 669                       btrfs_qgroup_level(child_id),
 670                       btrfs_qgroup_subvid(child_id));
 671                 return -ENOENT;
 672         }
 673
 674         parent = qgroup_tree_search(qgroup_lookup, parent_id);
 675         if (!parent) {
 676                 error("cannot find the qgroup %llu/%llu",
 677                       btrfs_qgroup_level(parent_id),
 678                       btrfs_qgroup_subvid(parent_id));
 679                 return -ENOENT;
 680         }
 681
 682         list = malloc(sizeof(*list));
 683         if (!list) {
 684                 error("memory allocation failed");
 685                 return -ENOMEM;
 686         }
 687
 688         list->qgroup = parent;
 689         list->member = child;
 690         list_add_tail(&list->next_qgroup, &child->qgroups);
 691         list_add_tail(&list->next_member, &parent->members);
 692
 693         return 0;
 694 }
 695
 696 static void __free_btrfs_qgroup(struct btrfs_qgroup *bq)
 697 {
 698         struct btrfs_qgroup_list *list;
 699         while (!list_empty(&bq->qgroups)) {
 700                 list = list_entry((&bq->qgroups)->next,
 701                                   struct btrfs_qgroup_list,
 702                                   next_qgroup);
 703                 list_del(&list->next_qgroup);
 704                 list_del(&list->next_member);
 705                 free(list);
 706         }
 707         while (!list_empty(&bq->members)) {
 708                 list = list_entry((&bq->members)->next,
 709                                   struct btrfs_qgroup_list,
 710                                   next_member);
 711                 list_del(&list->next_qgroup);
 712                 list_del(&list->next_member);
 713                 free(list);
 714         }
 715         free(bq);
 716 }
 717
 718 static void __free_all_qgroups(struct qgroup_lookup *root_tree)
 719 {
 720         struct btrfs_qgroup *entry;
 721         struct rb_node *n;
 722
 723         n = rb_first(&root_tree->root);
 724         while (n) {
 725                 entry = rb_entry(n, struct btrfs_qgroup, rb_node);
 726                 rb_erase(n, &root_tree->root);
 727                 __free_btrfs_qgroup(entry);
 728
 729                 n = rb_first(&root_tree->root);
 730         }
 731 }
 732
 733 static int filter_all_parent_insert(struct qgroup_lookup *sort_tree,
 734                                     struct btrfs_qgroup *bq)
 735 {
 736         struct rb_node **p = &sort_tree->root.rb_node;
 737         struct rb_node *parent = NULL;
 738         struct btrfs_qgroup *curr;
 739         int ret;
 740
 741         while (*p) {
 742                 parent = *p;
 743                 curr = rb_entry(parent, struct btrfs_qgroup, all_parent_node);
 744
 745                 ret = comp_entry_with_qgroupid(bq, curr, 0);
 746                 if (ret < 0)
 747                         p = &(*p)->rb_left;
 748                 else if (ret > 0)
 749                         p = &(*p)->rb_right;
 750                 else
 751                         return -EEXIST;
 752         }
 753         rb_link_node(&bq->all_parent_node, parent, p);
 754         rb_insert_color(&bq->all_parent_node, &sort_tree->root);
 755         return 0;
 756 }
 757
 758 static int filter_by_parent(struct btrfs_qgroup *bq, u64 data)
 759 {
 760         struct btrfs_qgroup *qgroup =
 761                 (struct btrfs_qgroup *)(unsigned long)data;
 762
 763         if (data == 0)
 764                 return 0;
 765         if (qgroup->qgroupid == bq->qgroupid)
 766                 return 1;
 767         return 0;
 768 }
 769
 770 static int filter_by_all_parent(struct btrfs_qgroup *bq, u64 data)
 771 {
 772         struct qgroup_lookup lookup;
 773         struct qgroup_lookup *ql = &lookup;
 774         struct btrfs_qgroup_list *list;
 775         struct rb_node *n;
 776         struct btrfs_qgroup *qgroup =
 777                          (struct btrfs_qgroup *)(unsigned long)data;
 778
 779         if (data == 0)
 780                 return 0;
 781         if (bq->qgroupid == qgroup->qgroupid)
 782                 return 1;
 783
 784         qgroup_lookup_init(ql);
 785         filter_all_parent_insert(ql, qgroup);
 786         n = rb_first(&ql->root);
 787         while (n) {
 788                 qgroup = rb_entry(n, struct btrfs_qgroup, all_parent_node);
 789                 if (!list_empty(&qgroup->qgroups)) {
 790                         list_for_each_entry(list, &qgroup->qgroups,
 791                                             next_qgroup) {
 792                                 if ((list->qgroup)->qgroupid == bq->qgroupid)
 793                                         return 1;
 794                                 filter_all_parent_insert(ql, list->qgroup);
 795                         }
 796                 }
 797                 rb_erase(n, &ql->root);
 798                 n = rb_first(&ql->root);
 799         }
 800         return 0;
 801 }
 802
 803 static btrfs_qgroup_filter_func all_filter_funcs[] = {
 804         [BTRFS_QGROUP_FILTER_PARENT]            = filter_by_parent,
 805         [BTRFS_QGROUP_FILTER_ALL_PARENT]        = filter_by_all_parent,
 806 };
 807
 808 struct btrfs_qgroup_filter_set *btrfs_qgroup_alloc_filter_set(void)
 809 {
 810         struct btrfs_qgroup_filter_set *set;
 811         int size;
 812
 813         size = sizeof(struct btrfs_qgroup_filter_set) +
 814                BTRFS_QGROUP_NFILTERS_INCREASE *
 815                sizeof(struct btrfs_qgroup_filter);
 816         set = calloc(1, size);
 817         if (!set) {
 818                 error("memory allocation failed");
 819                 exit(1);
 820         }
 821         set->total = BTRFS_QGROUP_NFILTERS_INCREASE;
 822
 823         return set;
 824 }
 825
 826 int btrfs_qgroup_setup_filter(struct btrfs_qgroup_filter_set **filter_set,
 827                               enum btrfs_qgroup_filter_enum filter, u64 data)
 828 {
 829         struct btrfs_qgroup_filter_set *set = *filter_set;
 830         int size;
 831
 832         ASSERT(set != NULL);
 833         ASSERT(filter < BTRFS_QGROUP_FILTER_MAX);
 834         ASSERT(set->nfilters <= set->total);
 835
 836         if (set->nfilters == set->total) {
 837                 void *tmp;
 838
 839                 size = set->total + BTRFS_QGROUP_NFILTERS_INCREASE;
 840                 size = sizeof(*set) + size * sizeof(struct btrfs_qgroup_filter);
 841
 842                 tmp = set;
 843                 set = realloc(set, size);
 844                 if (!set) {
 845                         error("memory allocation failed");
 846                         free(tmp);
 847                         exit(1);
 848                 }
 849                 memset(&set->filters[set->total], 0,
 850                        BTRFS_QGROUP_NFILTERS_INCREASE *
 851                        sizeof(struct btrfs_qgroup_filter));
 852                 set->total += BTRFS_QGROUP_NFILTERS_INCREASE;
 853                 *filter_set = set;
 854         }
 855
 856         ASSERT(set->filters[set->nfilters].filter_func == NULL);
 857         set->filters[set->nfilters].filter_func = all_filter_funcs[filter];
 858         set->filters[set->nfilters].data = data;
 859         set->nfilters++;
 860         return 0;
 861 }
 862
 863 static int filter_qgroup(struct btrfs_qgroup *bq,
 864                          struct btrfs_qgroup_filter_set *set)
 865 {
 866         int i, ret;
 867
 868         if (!set || !set->nfilters)
 869                 return 1;
 870         for (i = 0; i < set->nfilters; i++) {
 871                 if (!set->filters[i].filter_func)
 872                         break;
 873                 ret = set->filters[i].filter_func(bq, set->filters[i].data);
 874                 if (!ret)
 875                         return 0;
 876         }
 877         return 1;
 878 }
 879
 880 static void pre_process_filter_set(struct qgroup_lookup *lookup,
 881                                    struct btrfs_qgroup_filter_set *set)
 882 {
 883         int i;
 884         struct btrfs_qgroup *qgroup_for_filter = NULL;
 885
 886         for (i = 0; i < set->nfilters; i++) {
 887
 888                 if (set->filters[i].filter_func == filter_by_all_parent
 889                     || set->filters[i].filter_func == filter_by_parent) {
 890                         qgroup_for_filter = qgroup_tree_search(lookup,
 891                                             set->filters[i].data);
 892                         set->filters[i].data =
 893                                  (u64)(unsigned long)qgroup_for_filter;
 894                 }
 895         }
 896 }
 897
 898 static int sort_tree_insert(struct qgroup_lookup *sort_tree,
 899                             struct btrfs_qgroup *bq,
 900                             struct btrfs_qgroup_comparer_set *comp_set)
 901 {
 902         struct rb_node **p = &sort_tree->root.rb_node;
 903         struct rb_node *parent = NULL;
 904         struct btrfs_qgroup *curr;
 905         int ret;
 906
 907         while (*p) {
 908                 parent = *p;
 909                 curr = rb_entry(parent, struct btrfs_qgroup, sort_node);
 910
 911                 ret = sort_comp(bq, curr, comp_set);
 912                 if (ret < 0)
 913                         p = &(*p)->rb_left;
 914                 else if (ret > 0)
 915                         p = &(*p)->rb_right;
 916                 else
 917                         return -EEXIST;
 918         }
 919         rb_link_node(&bq->sort_node, parent, p);
 920         rb_insert_color(&bq->sort_node, &sort_tree->root);
 921         return 0;
 922 }
 923
 924 static void __update_columns_max_len(struct btrfs_qgroup *bq,
 925                                      enum btrfs_qgroup_column_enum column)
 926 {
 927         struct btrfs_qgroup_list *list = NULL;
 928         char tmp[100];
 929         int len;
 930         unsigned unit_mode = btrfs_qgroup_columns[column].unit_mode;
 931
 932         ASSERT(0 <= column && column < BTRFS_QGROUP_ALL);
 933
 934         switch (column) {
 935
 936         case BTRFS_QGROUP_QGROUPID:
 937                 sprintf(tmp, "%llu/%llu",
 938                         btrfs_qgroup_level(bq->qgroupid),
 939                         btrfs_qgroup_subvid(bq->qgroupid));
 940                 len = strlen(tmp);
 941                 if (btrfs_qgroup_columns[column].max_len < len)
 942                         btrfs_qgroup_columns[column].max_len = len;
 943                 break;
 944         case BTRFS_QGROUP_RFER:
 945                 len = strlen(pretty_size_mode(bq->rfer, unit_mode));
 946                 if (btrfs_qgroup_columns[column].max_len < len)
 947                         btrfs_qgroup_columns[column].max_len = len;
 948                 break;
 949         case BTRFS_QGROUP_EXCL:
 950                 len = strlen(pretty_size_mode(bq->excl, unit_mode));
 951                 if (btrfs_qgroup_columns[column].max_len < len)
 952                         btrfs_qgroup_columns[column].max_len = len;
 953                 break;
 954         case BTRFS_QGROUP_MAX_RFER:
 955                 len = strlen(pretty_size_mode(bq->max_rfer, unit_mode));
 956                 if (btrfs_qgroup_columns[column].max_len < len)
 957                         btrfs_qgroup_columns[column].max_len = len;
 958                 break;
 959         case BTRFS_QGROUP_MAX_EXCL:
 960                 len = strlen(pretty_size_mode(bq->max_excl, unit_mode));
 961                 if (btrfs_qgroup_columns[column].max_len < len)
 962                         btrfs_qgroup_columns[column].max_len = len;
 963                 break;
 964         case BTRFS_QGROUP_PARENT:
 965                 len = 0;
 966                 list_for_each_entry(list, &bq->qgroups, next_qgroup) {
 967                         len += sprintf(tmp, "%llu/%llu",
 968                                 btrfs_qgroup_level(list->qgroup->qgroupid),
 969                                 btrfs_qgroup_subvid(list->qgroup->qgroupid));
 970                         if (!list_is_last(&list->next_qgroup, &bq->qgroups))
 971                                 len += 1;
 972                 }
 973                 if (btrfs_qgroup_columns[column].max_len < len)
 974                         btrfs_qgroup_columns[column].max_len = len;
 975                 break;
 976         case BTRFS_QGROUP_CHILD:
 977                 len = 0;
 978                 list_for_each_entry(list, &bq->members, next_member) {
 979                         len += sprintf(tmp, "%llu/%llu",
 980                                 btrfs_qgroup_level(list->member->qgroupid),
 981                                 btrfs_qgroup_subvid(list->member->qgroupid));
 982                         if (!list_is_last(&list->next_member, &bq->members))
 983                                 len += 1;
 984                 }
 985                 if (btrfs_qgroup_columns[column].max_len < len)
 986                         btrfs_qgroup_columns[column].max_len = len;
 987                 break;
 988         default:
 989                 break;
 990         }
 991
 992 }
 993
 994 static void update_columns_max_len(struct btrfs_qgroup *bq)
 995 {
 996         int i;
 997
 998         for (i = 0; i < BTRFS_QGROUP_ALL; i++) {
 999                 if (!btrfs_qgroup_columns[i].need_print)
1000                         continue;
1001                 __update_columns_max_len(bq, i);
1002         }
1003 }
1004
1005 static void __filter_and_sort_qgroups(struct qgroup_lookup *all_qgroups,
1006                                  struct qgroup_lookup *sort_tree,
1007                                  struct btrfs_qgroup_filter_set *filter_set,
1008                                  struct btrfs_qgroup_comparer_set *comp_set)
1009 {
1010         struct rb_node *n;
1011         struct btrfs_qgroup *entry;
1012         int ret;
1013
1014         qgroup_lookup_init(sort_tree);
1015         pre_process_filter_set(all_qgroups, filter_set);
1016
1017         n = rb_last(&all_qgroups->root);
1018         while (n) {
1019                 entry = rb_entry(n, struct btrfs_qgroup, rb_node);
1020
1021                 ret = filter_qgroup(entry, filter_set);
1022                 if (ret) {
1023                         sort_tree_insert(sort_tree, entry, comp_set);
1024
1025                         update_columns_max_len(entry);
1026                 }
1027                 n = rb_prev(n);
1028         }
1029 }
1030
1031 static inline void print_status_flag_warning(u64 flags)
1032 {
1033         if (!(flags & BTRFS_QGROUP_STATUS_FLAG_ON))
1034                 warning("quota disabled, qgroup data may be out of date");
1035         else if (flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
1036                 warning("rescan is running, qgroup data may be incorrect");
1037         else if (flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT)
1038                 warning("qgroup data inconsistent, rescan recommended");
1039 }
1040
1041 static int __qgroups_search(int fd, struct qgroup_lookup *qgroup_lookup)
1042 {
1043         int ret;
1044         struct btrfs_ioctl_search_args args;
1045         struct btrfs_ioctl_search_key *sk = &args.key;
1046         struct btrfs_ioctl_search_header *sh;
1047         unsigned long off = 0;
1048         unsigned int i;
1049         struct btrfs_qgroup_info_item *info;
1050         struct btrfs_qgroup_limit_item *limit;
1051         u64 qgroupid;
1052         u64 qgroupid1;
1053
1054         memset(&args, 0, sizeof(args));
1055
1056         sk->tree_id = BTRFS_QUOTA_TREE_OBJECTID;
1057         sk->max_type = BTRFS_QGROUP_RELATION_KEY;
1058         sk->min_type = BTRFS_QGROUP_STATUS_KEY;
1059         sk->max_objectid = (u64)-1;
1060         sk->max_offset = (u64)-1;
1061         sk->max_transid = (u64)-1;
1062         sk->nr_items = 4096;
1063
1064         qgroup_lookup_init(qgroup_lookup);
1065
1066         while (1) {
1067                 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
1068                 if (ret < 0)
1069                         return -errno;
1070
1071                 /* the ioctl returns the number of item it found in nr_items */
1072                 if (sk->nr_items == 0)
1073                         break;
1074
1075                 off = 0;
1076                 /*
1077                  * for each item, pull the key out of the header and then
1078                  * read the root_ref item it contains
1079                  */
1080                 for (i = 0; i < sk->nr_items; i++) {
1081                         sh = (struct btrfs_ioctl_search_header *)(args.buf +
1082                                                                   off);
1083                         off += sizeof(*sh);
1084
1085                         if (btrfs_search_header_type(sh)
1086                             == BTRFS_QGROUP_STATUS_KEY) {
1087                                 struct btrfs_qgroup_status_item *si;
1088                                 u64 flags;
1089
1090                                 si = (struct btrfs_qgroup_status_item *)
1091                                      (args.buf + off);
1092                                 flags = btrfs_stack_qgroup_status_flags(si);
1093                                 print_status_flag_warning(flags);
1094                         } else if (btrfs_search_header_type(sh)
1095                                    == BTRFS_QGROUP_INFO_KEY) {
1096                                 qgroupid = btrfs_search_header_offset(sh);
1097                                 info = (struct btrfs_qgroup_info_item *)
1098                                        (args.buf + off);
1099
1100                                 update_qgroup_info(qgroup_lookup, qgroupid,
1101                                                    info);
1102                         } else if (btrfs_search_header_type(sh)
1103                                    == BTRFS_QGROUP_LIMIT_KEY) {
1104                                 qgroupid = btrfs_search_header_offset(sh);
1105                                 limit = (struct btrfs_qgroup_limit_item *)
1106                                         (args.buf + off);
1107
1108                                 update_qgroup_limit(qgroup_lookup, qgroupid,
1109                                                     limit);
1110                         } else if (btrfs_search_header_type(sh)
1111                                    == BTRFS_QGROUP_RELATION_KEY) {
1112                                 qgroupid = btrfs_search_header_offset(sh);
1113                                 qgroupid1 = btrfs_search_header_objectid(sh);
1114
1115                                 if (qgroupid < qgroupid1)
1116                                         goto skip;
1117
1118                                 update_qgroup_relation(qgroup_lookup, qgroupid,
1119                                                        qgroupid1);
1120                         } else
1121                                 goto done;
1122 skip:
1123                         off += btrfs_search_header_len(sh);
1124
1125                         /*
1126                          * record the mins in sk so we can make sure the
1127                          * next search doesn't repeat this root
1128                          */
1129                         sk->min_type = btrfs_search_header_type(sh);
1130                         sk->min_offset = btrfs_search_header_offset(sh);
1131                         sk->min_objectid = btrfs_search_header_objectid(sh);
1132                 }
1133                 sk->nr_items = 4096;
1134                 /*
1135                  * this iteration is done, step forward one qgroup for the next
1136                  * ioctl
1137                  */
1138                 if (sk->min_offset < (u64)-1)
1139                         sk->min_offset++;
1140                 else
1141                         break;
1142         }
1143
1144 done:
1145         return ret;
1146 }
1147
1148 static void print_all_qgroups(struct qgroup_lookup *qgroup_lookup)
1149 {
1150
1151         struct rb_node *n;
1152         struct btrfs_qgroup *entry;
1153
1154         print_table_head();
1155
1156         n = rb_first(&qgroup_lookup->root);
1157         while (n) {
1158                 entry = rb_entry(n, struct btrfs_qgroup, sort_node);
1159                 print_single_qgroup_table(entry);
1160                 n = rb_next(n);
1161         }
1162 }
1163
1164 int btrfs_show_qgroups(int fd,
1165                        struct btrfs_qgroup_filter_set *filter_set,
1166                        struct btrfs_qgroup_comparer_set *comp_set)
1167 {
1168
1169         struct qgroup_lookup qgroup_lookup;
1170         struct qgroup_lookup sort_tree;
1171         int ret;
1172
1173         ret = __qgroups_search(fd, &qgroup_lookup);
1174         if (ret)
1175                 return ret;
1176         __filter_and_sort_qgroups(&qgroup_lookup, &sort_tree,
1177                                   filter_set, comp_set);
1178         print_all_qgroups(&sort_tree);
1179
1180         __free_all_qgroups(&qgroup_lookup);
1181         free(filter_set);
1182         free(comp_set);
1183         return ret;
1184 }
1185
1186 int btrfs_qgroup_parse_sort_string(const char *opt_arg,
1187                                    struct btrfs_qgroup_comparer_set **comps)
1188 {
1189         int order;
1190         int flag;
1191         char *p;
1192         char **ptr_argv;
1193         int what_to_sort;
1194         char *opt_tmp;
1195         int ret = 0;
1196
1197         opt_tmp = strdup(opt_arg);
1198         if (!opt_tmp)
1199                 return -ENOMEM;
1200
1201         p = strtok(opt_tmp, ",");
1202         while (p) {
1203                 flag = 0;
1204                 ptr_argv = all_sort_items;
1205
1206                 while (*ptr_argv) {
1207                         if (strcmp(*ptr_argv, p) == 0) {
1208                                 flag = 1;
1209                                 break;
1210                         } else {
1211                                 p++;
1212                                 if (strcmp(*ptr_argv, p) == 0) {
1213                                         flag = 1;
1214                                         p--;
1215                                         break;
1216                                 }
1217                                 p--;
1218                         }
1219                         ptr_argv++;
1220                 }
1221
1222                 if (flag == 0) {
1223                         ret = -1;
1224                         goto out;
1225                 } else {
1226                         if (*p == '+') {
1227                                 order = 0;
1228                                 p++;
1229                         } else if (*p == '-') {
1230                                 order = 1;
1231                                 p++;
1232                         } else
1233                                 order = 0;
1234
1235                         what_to_sort = btrfs_qgroup_get_sort_item(p);
1236                         if (what_to_sort < 0) {
1237                                 ret = -1;
1238                                 goto out;
1239                         }
1240                         btrfs_qgroup_setup_comparer(comps, what_to_sort, order);
1241                 }
1242                 p = strtok(NULL, ",");
1243         }
1244
1245 out:
1246         free(opt_tmp);
1247         return ret;
1248 }
1249
1250 int qgroup_inherit_size(struct btrfs_qgroup_inherit *p)
1251 {
1252         return sizeof(*p) + sizeof(p->qgroups[0]) *
1253                             (p->num_qgroups + 2 * p->num_ref_copies +
1254                              2 * p->num_excl_copies);
1255 }
1256
1257 static int
1258 qgroup_inherit_realloc(struct btrfs_qgroup_inherit **inherit, int n, int pos)
1259 {
1260         struct btrfs_qgroup_inherit *out;
1261         int nitems = 0;
1262
1263         if (*inherit) {
1264                 nitems = (*inherit)->num_qgroups +
1265                          (*inherit)->num_ref_copies +
1266                          (*inherit)->num_excl_copies;
1267         }
1268
1269         out = calloc(sizeof(*out) + sizeof(out->qgroups[0]) * (nitems + n), 1);
1270         if (out == NULL) {
1271                 error("not enough memory");
1272                 return -ENOMEM;
1273         }
1274
1275         if (*inherit) {
1276                 struct btrfs_qgroup_inherit *i = *inherit;
1277                 int s = sizeof(out->qgroups[0]);
1278
1279                 out->num_qgroups = i->num_qgroups;
1280                 out->num_ref_copies = i->num_ref_copies;
1281                 out->num_excl_copies = i->num_excl_copies;
1282                 memcpy(out->qgroups, i->qgroups, pos * s);
1283                 memcpy(out->qgroups + pos + n, i->qgroups + pos,
1284                        (nitems - pos) * s);
1285         }
1286         free(*inherit);
1287         *inherit = out;
1288
1289         return 0;
1290 }
1291
1292 int qgroup_inherit_add_group(struct btrfs_qgroup_inherit **inherit, char *arg)
1293 {
1294         int ret;
1295         u64 qgroupid = parse_qgroupid(arg);
1296         int pos = 0;
1297
1298         if (qgroupid == 0) {
1299                 error("invalid qgroup specification, qgroupid must not 0");
1300                 return -EINVAL;
1301         }
1302
1303         if (*inherit)
1304                 pos = (*inherit)->num_qgroups;
1305         ret = qgroup_inherit_realloc(inherit, 1, pos);
1306         if (ret)
1307                 return ret;
1308
1309         (*inherit)->qgroups[(*inherit)->num_qgroups++] = qgroupid;
1310
1311         return 0;
1312 }
1313
1314 int qgroup_inherit_add_copy(struct btrfs_qgroup_inherit **inherit, char *arg,
1315                             int type)
1316 {
1317         int ret;
1318         u64 qgroup_src;
1319         u64 qgroup_dst;
1320         char *p;
1321         int pos = 0;
1322
1323         p = strchr(arg, ':');
1324         if (!p) {
1325 bad:
1326                 error("invalid copy specification, missing separator :");
1327                 return -EINVAL;
1328         }
1329         *p = 0;
1330         qgroup_src = parse_qgroupid(arg);
1331         qgroup_dst = parse_qgroupid(p + 1);
1332         *p = ':';
1333
1334         if (!qgroup_src || !qgroup_dst)
1335                 goto bad;
1336
1337         if (*inherit)
1338                 pos = (*inherit)->num_qgroups +
1339                       (*inherit)->num_ref_copies * 2 * type;
1340
1341         ret = qgroup_inherit_realloc(inherit, 2, pos);
1342         if (ret)
1343                 return ret;
1344
1345         (*inherit)->qgroups[pos++] = qgroup_src;
1346         (*inherit)->qgroups[pos++] = qgroup_dst;
1347
1348         if (!type)
1349                 ++(*inherit)->num_ref_copies;
1350         else
1351                 ++(*inherit)->num_excl_copies;
1352
1353         return 0;
1354 }