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v4.6
 
   1/*
   2 * Copyright (C) 2011 STRATO.  All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public
   6 * License v2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public
  14 * License along with this program; if not, write to the
  15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16 * Boston, MA 021110-1307, USA.
  17 */
  18
  19#include <linux/sched.h>
  20#include <linux/pagemap.h>
  21#include <linux/writeback.h>
  22#include <linux/blkdev.h>
  23#include <linux/rbtree.h>
  24#include <linux/slab.h>
  25#include <linux/workqueue.h>
  26#include <linux/btrfs.h>
 
  27
  28#include "ctree.h"
  29#include "transaction.h"
  30#include "disk-io.h"
  31#include "locking.h"
  32#include "ulist.h"
  33#include "backref.h"
  34#include "extent_io.h"
  35#include "qgroup.h"
 
 
 
 
 
 
 
 
  36
 
 
 
 
 
 
 
 
  37
  38/* TODO XXX FIXME
  39 *  - subvol delete -> delete when ref goes to 0? delete limits also?
  40 *  - reorganize keys
  41 *  - compressed
  42 *  - sync
  43 *  - copy also limits on subvol creation
  44 *  - limit
  45 *  - caches fuer ulists
  46 *  - performance benchmarks
  47 *  - check all ioctl parameters
  48 */
  49
  50/*
  51 * one struct for each qgroup, organized in fs_info->qgroup_tree.
 
 
  52 */
  53struct btrfs_qgroup {
  54	u64 qgroupid;
  55
  56	/*
  57	 * state
  58	 */
  59	u64 rfer;	/* referenced */
  60	u64 rfer_cmpr;	/* referenced compressed */
  61	u64 excl;	/* exclusive */
  62	u64 excl_cmpr;	/* exclusive compressed */
  63
  64	/*
  65	 * limits
  66	 */
  67	u64 lim_flags;	/* which limits are set */
  68	u64 max_rfer;
  69	u64 max_excl;
  70	u64 rsv_rfer;
  71	u64 rsv_excl;
  72
  73	/*
  74	 * reservation tracking
  75	 */
  76	u64 reserved;
  77
  78	/*
  79	 * lists
  80	 */
  81	struct list_head groups;  /* groups this group is member of */
  82	struct list_head members; /* groups that are members of this group */
  83	struct list_head dirty;   /* dirty groups */
  84	struct rb_node node;	  /* tree of qgroups */
 
 
 
 
 
  85
  86	/*
  87	 * temp variables for accounting operations
  88	 * Refer to qgroup_shared_accouting() for details.
  89	 */
  90	u64 old_refcnt;
  91	u64 new_refcnt;
  92};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  93
  94static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
  95					   int mod)
  96{
  97	if (qg->old_refcnt < seq)
  98		qg->old_refcnt = seq;
  99	qg->old_refcnt += mod;
 100}
 101
 102static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
 103					   int mod)
 104{
 105	if (qg->new_refcnt < seq)
 106		qg->new_refcnt = seq;
 107	qg->new_refcnt += mod;
 108}
 109
 110static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
 111{
 112	if (qg->old_refcnt < seq)
 113		return 0;
 114	return qg->old_refcnt - seq;
 115}
 116
 117static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
 118{
 119	if (qg->new_refcnt < seq)
 120		return 0;
 121	return qg->new_refcnt - seq;
 122}
 123
 124/*
 125 * glue structure to represent the relations between qgroups.
 126 */
 127struct btrfs_qgroup_list {
 128	struct list_head next_group;
 129	struct list_head next_member;
 130	struct btrfs_qgroup *group;
 131	struct btrfs_qgroup *member;
 132};
 133
 134#define ptr_to_u64(x) ((u64)(uintptr_t)x)
 135#define u64_to_ptr(x) ((struct btrfs_qgroup *)(uintptr_t)x)
 136
 137static int
 138qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
 139		   int init_flags);
 140static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 141
 142/* must be called with qgroup_ioctl_lock held */
 143static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
 144					   u64 qgroupid)
 145{
 146	struct rb_node *n = fs_info->qgroup_tree.rb_node;
 147	struct btrfs_qgroup *qgroup;
 148
 149	while (n) {
 150		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 151		if (qgroup->qgroupid < qgroupid)
 152			n = n->rb_left;
 153		else if (qgroup->qgroupid > qgroupid)
 154			n = n->rb_right;
 155		else
 156			return qgroup;
 157	}
 158	return NULL;
 159}
 160
 161/* must be called with qgroup_lock held */
 
 
 
 
 
 
 
 162static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
 
 163					  u64 qgroupid)
 164{
 165	struct rb_node **p = &fs_info->qgroup_tree.rb_node;
 166	struct rb_node *parent = NULL;
 167	struct btrfs_qgroup *qgroup;
 168
 
 
 
 169	while (*p) {
 170		parent = *p;
 171		qgroup = rb_entry(parent, struct btrfs_qgroup, node);
 172
 173		if (qgroup->qgroupid < qgroupid)
 174			p = &(*p)->rb_left;
 175		else if (qgroup->qgroupid > qgroupid)
 176			p = &(*p)->rb_right;
 177		else
 
 178			return qgroup;
 
 179	}
 180
 181	qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
 182	if (!qgroup)
 183		return ERR_PTR(-ENOMEM);
 184
 185	qgroup->qgroupid = qgroupid;
 186	INIT_LIST_HEAD(&qgroup->groups);
 187	INIT_LIST_HEAD(&qgroup->members);
 188	INIT_LIST_HEAD(&qgroup->dirty);
 
 
 189
 190	rb_link_node(&qgroup->node, parent, p);
 191	rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
 192
 193	return qgroup;
 194}
 195
 196static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
 
 197{
 198	struct btrfs_qgroup_list *list;
 199
 200	list_del(&qgroup->dirty);
 201	while (!list_empty(&qgroup->groups)) {
 202		list = list_first_entry(&qgroup->groups,
 203					struct btrfs_qgroup_list, next_group);
 204		list_del(&list->next_group);
 205		list_del(&list->next_member);
 206		kfree(list);
 207	}
 208
 209	while (!list_empty(&qgroup->members)) {
 210		list = list_first_entry(&qgroup->members,
 211					struct btrfs_qgroup_list, next_member);
 212		list_del(&list->next_group);
 213		list_del(&list->next_member);
 214		kfree(list);
 215	}
 216	kfree(qgroup);
 217}
 218
 219/* must be called with qgroup_lock held */
 220static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
 221{
 222	struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
 223
 224	if (!qgroup)
 225		return -ENOENT;
 226
 227	rb_erase(&qgroup->node, &fs_info->qgroup_tree);
 228	__del_qgroup_rb(qgroup);
 229	return 0;
 230}
 231
 232/* must be called with qgroup_lock held */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 233static int add_relation_rb(struct btrfs_fs_info *fs_info,
 
 234			   u64 memberid, u64 parentid)
 235{
 236	struct btrfs_qgroup *member;
 237	struct btrfs_qgroup *parent;
 238	struct btrfs_qgroup_list *list;
 239
 240	member = find_qgroup_rb(fs_info, memberid);
 241	parent = find_qgroup_rb(fs_info, parentid);
 242	if (!member || !parent)
 243		return -ENOENT;
 244
 245	list = kzalloc(sizeof(*list), GFP_ATOMIC);
 246	if (!list)
 247		return -ENOMEM;
 248
 249	list->group = parent;
 250	list->member = member;
 251	list_add_tail(&list->next_group, &member->groups);
 252	list_add_tail(&list->next_member, &parent->members);
 253
 254	return 0;
 255}
 256
 257/* must be called with qgroup_lock held */
 258static int del_relation_rb(struct btrfs_fs_info *fs_info,
 259			   u64 memberid, u64 parentid)
 260{
 261	struct btrfs_qgroup *member;
 262	struct btrfs_qgroup *parent;
 263	struct btrfs_qgroup_list *list;
 264
 265	member = find_qgroup_rb(fs_info, memberid);
 266	parent = find_qgroup_rb(fs_info, parentid);
 267	if (!member || !parent)
 268		return -ENOENT;
 269
 270	list_for_each_entry(list, &member->groups, next_group) {
 271		if (list->group == parent) {
 272			list_del(&list->next_group);
 273			list_del(&list->next_member);
 274			kfree(list);
 275			return 0;
 276		}
 277	}
 278	return -ENOENT;
 279}
 280
 281#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 282int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
 283			       u64 rfer, u64 excl)
 284{
 285	struct btrfs_qgroup *qgroup;
 286
 287	qgroup = find_qgroup_rb(fs_info, qgroupid);
 288	if (!qgroup)
 289		return -EINVAL;
 290	if (qgroup->rfer != rfer || qgroup->excl != excl)
 291		return -EINVAL;
 292	return 0;
 293}
 294#endif
 295
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 296/*
 297 * The full config is read in one go, only called from open_ctree()
 298 * It doesn't use any locking, as at this point we're still single-threaded
 299 */
 300int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
 301{
 302	struct btrfs_key key;
 303	struct btrfs_key found_key;
 304	struct btrfs_root *quota_root = fs_info->quota_root;
 305	struct btrfs_path *path = NULL;
 306	struct extent_buffer *l;
 307	int slot;
 308	int ret = 0;
 309	u64 flags = 0;
 310	u64 rescan_progress = 0;
 311
 312	if (!fs_info->quota_enabled)
 313		return 0;
 314
 315	fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
 316	if (!fs_info->qgroup_ulist) {
 317		ret = -ENOMEM;
 318		goto out;
 319	}
 320
 321	path = btrfs_alloc_path();
 322	if (!path) {
 323		ret = -ENOMEM;
 324		goto out;
 325	}
 326
 
 
 
 327	/* default this to quota off, in case no status key is found */
 328	fs_info->qgroup_flags = 0;
 329
 330	/*
 331	 * pass 1: read status, all qgroup infos and limits
 332	 */
 333	key.objectid = 0;
 334	key.type = 0;
 335	key.offset = 0;
 336	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
 337	if (ret)
 338		goto out;
 339
 340	while (1) {
 341		struct btrfs_qgroup *qgroup;
 342
 343		slot = path->slots[0];
 344		l = path->nodes[0];
 345		btrfs_item_key_to_cpu(l, &found_key, slot);
 346
 347		if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
 348			struct btrfs_qgroup_status_item *ptr;
 349
 350			ptr = btrfs_item_ptr(l, slot,
 351					     struct btrfs_qgroup_status_item);
 352
 353			if (btrfs_qgroup_status_version(l, ptr) !=
 354			    BTRFS_QGROUP_STATUS_VERSION) {
 355				btrfs_err(fs_info,
 356				 "old qgroup version, quota disabled");
 357				goto out;
 358			}
 359			if (btrfs_qgroup_status_generation(l, ptr) !=
 360			    fs_info->generation) {
 361				flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 
 
 362				btrfs_err(fs_info,
 363					"qgroup generation mismatch, "
 364					"marked as inconsistent");
 365			}
 366			fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
 367									  ptr);
 368			rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
 369			goto next1;
 370		}
 371
 372		if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
 373		    found_key.type != BTRFS_QGROUP_LIMIT_KEY)
 374			goto next1;
 375
 376		qgroup = find_qgroup_rb(fs_info, found_key.offset);
 377		if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
 378		    (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
 379			btrfs_err(fs_info, "inconsistent qgroup config");
 380			flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 381		}
 382		if (!qgroup) {
 383			qgroup = add_qgroup_rb(fs_info, found_key.offset);
 384			if (IS_ERR(qgroup)) {
 385				ret = PTR_ERR(qgroup);
 
 
 386				goto out;
 387			}
 
 388		}
 
 
 
 
 389		switch (found_key.type) {
 390		case BTRFS_QGROUP_INFO_KEY: {
 391			struct btrfs_qgroup_info_item *ptr;
 392
 393			ptr = btrfs_item_ptr(l, slot,
 394					     struct btrfs_qgroup_info_item);
 395			qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
 396			qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
 397			qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
 398			qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
 399			/* generation currently unused */
 400			break;
 401		}
 402		case BTRFS_QGROUP_LIMIT_KEY: {
 403			struct btrfs_qgroup_limit_item *ptr;
 404
 405			ptr = btrfs_item_ptr(l, slot,
 406					     struct btrfs_qgroup_limit_item);
 407			qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
 408			qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
 409			qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
 410			qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
 411			qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
 412			break;
 413		}
 414		}
 415next1:
 416		ret = btrfs_next_item(quota_root, path);
 417		if (ret < 0)
 418			goto out;
 419		if (ret)
 420			break;
 421	}
 422	btrfs_release_path(path);
 423
 424	/*
 425	 * pass 2: read all qgroup relations
 426	 */
 427	key.objectid = 0;
 428	key.type = BTRFS_QGROUP_RELATION_KEY;
 429	key.offset = 0;
 430	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
 431	if (ret)
 432		goto out;
 433	while (1) {
 
 
 434		slot = path->slots[0];
 435		l = path->nodes[0];
 436		btrfs_item_key_to_cpu(l, &found_key, slot);
 437
 438		if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
 439			goto next2;
 440
 441		if (found_key.objectid > found_key.offset) {
 442			/* parent <- member, not needed to build config */
 443			/* FIXME should we omit the key completely? */
 444			goto next2;
 445		}
 446
 447		ret = add_relation_rb(fs_info, found_key.objectid,
 
 
 
 
 
 448				      found_key.offset);
 
 449		if (ret == -ENOENT) {
 450			btrfs_warn(fs_info,
 451				"orphan qgroup relation 0x%llx->0x%llx",
 452				found_key.objectid, found_key.offset);
 453			ret = 0;	/* ignore the error */
 454		}
 455		if (ret)
 456			goto out;
 457next2:
 458		ret = btrfs_next_item(quota_root, path);
 459		if (ret < 0)
 460			goto out;
 461		if (ret)
 462			break;
 463	}
 464out:
 465	fs_info->qgroup_flags |= flags;
 466	if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)) {
 467		fs_info->quota_enabled = 0;
 468		fs_info->pending_quota_state = 0;
 469	} else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
 470		   ret >= 0) {
 471		ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
 472	}
 473	btrfs_free_path(path);
 474
 475	if (ret < 0) {
 
 
 
 
 
 476		ulist_free(fs_info->qgroup_ulist);
 477		fs_info->qgroup_ulist = NULL;
 478		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
 
 479	}
 480
 481	return ret < 0 ? ret : 0;
 482}
 483
 484/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 485 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
 486 * first two are in single-threaded paths.And for the third one, we have set
 487 * quota_root to be null with qgroup_lock held before, so it is safe to clean
 488 * up the in-memory structures without qgroup_lock held.
 489 */
 490void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
 491{
 492	struct rb_node *n;
 493	struct btrfs_qgroup *qgroup;
 494
 495	while ((n = rb_first(&fs_info->qgroup_tree))) {
 496		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 497		rb_erase(n, &fs_info->qgroup_tree);
 498		__del_qgroup_rb(qgroup);
 
 
 499	}
 500	/*
 501	 * we call btrfs_free_qgroup_config() when umounting
 502	 * filesystem and disabling quota, so we set qgroup_ulit
 503	 * to be null here to avoid double free.
 504	 */
 505	ulist_free(fs_info->qgroup_ulist);
 506	fs_info->qgroup_ulist = NULL;
 
 507}
 508
 509static int add_qgroup_relation_item(struct btrfs_trans_handle *trans,
 510				    struct btrfs_root *quota_root,
 511				    u64 src, u64 dst)
 512{
 513	int ret;
 
 514	struct btrfs_path *path;
 515	struct btrfs_key key;
 516
 517	path = btrfs_alloc_path();
 518	if (!path)
 519		return -ENOMEM;
 520
 521	key.objectid = src;
 522	key.type = BTRFS_QGROUP_RELATION_KEY;
 523	key.offset = dst;
 524
 525	ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
 526
 527	btrfs_mark_buffer_dirty(path->nodes[0]);
 528
 529	btrfs_free_path(path);
 530	return ret;
 531}
 532
 533static int del_qgroup_relation_item(struct btrfs_trans_handle *trans,
 534				    struct btrfs_root *quota_root,
 535				    u64 src, u64 dst)
 536{
 537	int ret;
 
 538	struct btrfs_path *path;
 539	struct btrfs_key key;
 540
 541	path = btrfs_alloc_path();
 542	if (!path)
 543		return -ENOMEM;
 544
 545	key.objectid = src;
 546	key.type = BTRFS_QGROUP_RELATION_KEY;
 547	key.offset = dst;
 548
 549	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 550	if (ret < 0)
 551		goto out;
 552
 553	if (ret > 0) {
 554		ret = -ENOENT;
 555		goto out;
 556	}
 557
 558	ret = btrfs_del_item(trans, quota_root, path);
 559out:
 560	btrfs_free_path(path);
 561	return ret;
 562}
 563
 564static int add_qgroup_item(struct btrfs_trans_handle *trans,
 565			   struct btrfs_root *quota_root, u64 qgroupid)
 566{
 567	int ret;
 568	struct btrfs_path *path;
 569	struct btrfs_qgroup_info_item *qgroup_info;
 570	struct btrfs_qgroup_limit_item *qgroup_limit;
 571	struct extent_buffer *leaf;
 572	struct btrfs_key key;
 573
 574	if (btrfs_test_is_dummy_root(quota_root))
 575		return 0;
 576
 577	path = btrfs_alloc_path();
 578	if (!path)
 579		return -ENOMEM;
 580
 581	key.objectid = 0;
 582	key.type = BTRFS_QGROUP_INFO_KEY;
 583	key.offset = qgroupid;
 584
 585	/*
 586	 * Avoid a transaction abort by catching -EEXIST here. In that
 587	 * case, we proceed by re-initializing the existing structure
 588	 * on disk.
 589	 */
 590
 591	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 592				      sizeof(*qgroup_info));
 593	if (ret && ret != -EEXIST)
 594		goto out;
 595
 596	leaf = path->nodes[0];
 597	qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
 598				 struct btrfs_qgroup_info_item);
 599	btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
 600	btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
 601	btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
 602	btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
 603	btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
 604
 605	btrfs_mark_buffer_dirty(leaf);
 606
 607	btrfs_release_path(path);
 608
 609	key.type = BTRFS_QGROUP_LIMIT_KEY;
 610	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 611				      sizeof(*qgroup_limit));
 612	if (ret && ret != -EEXIST)
 613		goto out;
 614
 615	leaf = path->nodes[0];
 616	qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
 617				  struct btrfs_qgroup_limit_item);
 618	btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
 619	btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
 620	btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
 621	btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
 622	btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
 623
 624	btrfs_mark_buffer_dirty(leaf);
 625
 626	ret = 0;
 627out:
 628	btrfs_free_path(path);
 629	return ret;
 630}
 631
 632static int del_qgroup_item(struct btrfs_trans_handle *trans,
 633			   struct btrfs_root *quota_root, u64 qgroupid)
 634{
 635	int ret;
 
 636	struct btrfs_path *path;
 637	struct btrfs_key key;
 638
 639	path = btrfs_alloc_path();
 640	if (!path)
 641		return -ENOMEM;
 642
 643	key.objectid = 0;
 644	key.type = BTRFS_QGROUP_INFO_KEY;
 645	key.offset = qgroupid;
 646	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 647	if (ret < 0)
 648		goto out;
 649
 650	if (ret > 0) {
 651		ret = -ENOENT;
 652		goto out;
 653	}
 654
 655	ret = btrfs_del_item(trans, quota_root, path);
 656	if (ret)
 657		goto out;
 658
 659	btrfs_release_path(path);
 660
 661	key.type = BTRFS_QGROUP_LIMIT_KEY;
 662	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 663	if (ret < 0)
 664		goto out;
 665
 666	if (ret > 0) {
 667		ret = -ENOENT;
 668		goto out;
 669	}
 670
 671	ret = btrfs_del_item(trans, quota_root, path);
 672
 673out:
 674	btrfs_free_path(path);
 675	return ret;
 676}
 677
 678static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
 679				    struct btrfs_root *root,
 680				    struct btrfs_qgroup *qgroup)
 681{
 
 682	struct btrfs_path *path;
 683	struct btrfs_key key;
 684	struct extent_buffer *l;
 685	struct btrfs_qgroup_limit_item *qgroup_limit;
 686	int ret;
 687	int slot;
 688
 689	key.objectid = 0;
 690	key.type = BTRFS_QGROUP_LIMIT_KEY;
 691	key.offset = qgroup->qgroupid;
 692
 693	path = btrfs_alloc_path();
 694	if (!path)
 695		return -ENOMEM;
 696
 697	ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 698	if (ret > 0)
 699		ret = -ENOENT;
 700
 701	if (ret)
 702		goto out;
 703
 704	l = path->nodes[0];
 705	slot = path->slots[0];
 706	qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
 707	btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
 708	btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
 709	btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
 710	btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
 711	btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
 712
 713	btrfs_mark_buffer_dirty(l);
 714
 715out:
 716	btrfs_free_path(path);
 717	return ret;
 718}
 719
 720static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
 721				   struct btrfs_root *root,
 722				   struct btrfs_qgroup *qgroup)
 723{
 
 
 724	struct btrfs_path *path;
 725	struct btrfs_key key;
 726	struct extent_buffer *l;
 727	struct btrfs_qgroup_info_item *qgroup_info;
 728	int ret;
 729	int slot;
 730
 731	if (btrfs_test_is_dummy_root(root))
 732		return 0;
 733
 734	key.objectid = 0;
 735	key.type = BTRFS_QGROUP_INFO_KEY;
 736	key.offset = qgroup->qgroupid;
 737
 738	path = btrfs_alloc_path();
 739	if (!path)
 740		return -ENOMEM;
 741
 742	ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 743	if (ret > 0)
 744		ret = -ENOENT;
 745
 746	if (ret)
 747		goto out;
 748
 749	l = path->nodes[0];
 750	slot = path->slots[0];
 751	qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 752	btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 753	btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 754	btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 755	btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 756	btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 757
 758	btrfs_mark_buffer_dirty(l);
 759
 760out:
 761	btrfs_free_path(path);
 762	return ret;
 763}
 764
 765static int update_qgroup_status_item(struct btrfs_trans_handle *trans,
 766				     struct btrfs_fs_info *fs_info,
 767				    struct btrfs_root *root)
 768{
 
 
 769	struct btrfs_path *path;
 770	struct btrfs_key key;
 771	struct extent_buffer *l;
 772	struct btrfs_qgroup_status_item *ptr;
 773	int ret;
 774	int slot;
 775
 776	key.objectid = 0;
 777	key.type = BTRFS_QGROUP_STATUS_KEY;
 778	key.offset = 0;
 779
 780	path = btrfs_alloc_path();
 781	if (!path)
 782		return -ENOMEM;
 783
 784	ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 785	if (ret > 0)
 786		ret = -ENOENT;
 787
 788	if (ret)
 789		goto out;
 790
 791	l = path->nodes[0];
 792	slot = path->slots[0];
 793	ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 794	btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
 
 795	btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 796	btrfs_set_qgroup_status_rescan(l, ptr,
 797				fs_info->qgroup_rescan_progress.objectid);
 798
 799	btrfs_mark_buffer_dirty(l);
 800
 801out:
 802	btrfs_free_path(path);
 803	return ret;
 804}
 805
 806/*
 807 * called with qgroup_lock held
 808 */
 809static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 810				  struct btrfs_root *root)
 811{
 812	struct btrfs_path *path;
 813	struct btrfs_key key;
 814	struct extent_buffer *leaf = NULL;
 815	int ret;
 816	int nr = 0;
 817
 818	path = btrfs_alloc_path();
 819	if (!path)
 820		return -ENOMEM;
 821
 822	path->leave_spinning = 1;
 823
 824	key.objectid = 0;
 825	key.offset = 0;
 826	key.type = 0;
 827
 828	while (1) {
 829		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 830		if (ret < 0)
 831			goto out;
 832		leaf = path->nodes[0];
 833		nr = btrfs_header_nritems(leaf);
 834		if (!nr)
 835			break;
 836		/*
 837		 * delete the leaf one by one
 838		 * since the whole tree is going
 839		 * to be deleted.
 840		 */
 841		path->slots[0] = 0;
 842		ret = btrfs_del_items(trans, root, path, 0, nr);
 843		if (ret)
 844			goto out;
 845
 846		btrfs_release_path(path);
 847	}
 848	ret = 0;
 849out:
 850	root->fs_info->pending_quota_state = 0;
 851	btrfs_free_path(path);
 852	return ret;
 853}
 854
 855int btrfs_quota_enable(struct btrfs_trans_handle *trans,
 856		       struct btrfs_fs_info *fs_info)
 857{
 858	struct btrfs_root *quota_root;
 859	struct btrfs_root *tree_root = fs_info->tree_root;
 860	struct btrfs_path *path = NULL;
 861	struct btrfs_qgroup_status_item *ptr;
 862	struct extent_buffer *leaf;
 863	struct btrfs_key key;
 864	struct btrfs_key found_key;
 865	struct btrfs_qgroup *qgroup = NULL;
 
 
 
 
 866	int ret = 0;
 867	int slot;
 868
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 869	mutex_lock(&fs_info->qgroup_ioctl_lock);
 870	if (fs_info->quota_root) {
 871		fs_info->pending_quota_state = 1;
 872		goto out;
 873	}
 874
 875	fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
 876	if (!fs_info->qgroup_ulist) {
 877		ret = -ENOMEM;
 878		goto out;
 879	}
 880
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 881	/*
 882	 * initially create the quota tree
 883	 */
 884	quota_root = btrfs_create_tree(trans, fs_info,
 885				       BTRFS_QUOTA_TREE_OBJECTID);
 886	if (IS_ERR(quota_root)) {
 887		ret =  PTR_ERR(quota_root);
 
 888		goto out;
 889	}
 890
 891	path = btrfs_alloc_path();
 892	if (!path) {
 893		ret = -ENOMEM;
 
 894		goto out_free_root;
 895	}
 896
 897	key.objectid = 0;
 898	key.type = BTRFS_QGROUP_STATUS_KEY;
 899	key.offset = 0;
 900
 901	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 902				      sizeof(*ptr));
 903	if (ret)
 
 904		goto out_free_path;
 
 905
 906	leaf = path->nodes[0];
 907	ptr = btrfs_item_ptr(leaf, path->slots[0],
 908				 struct btrfs_qgroup_status_item);
 909	btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
 910	btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
 911	fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
 912				BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 913	btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
 
 
 
 
 
 
 914	btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
 915
 916	btrfs_mark_buffer_dirty(leaf);
 917
 918	key.objectid = 0;
 919	key.type = BTRFS_ROOT_REF_KEY;
 920	key.offset = 0;
 921
 922	btrfs_release_path(path);
 923	ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
 924	if (ret > 0)
 925		goto out_add_root;
 926	if (ret < 0)
 
 927		goto out_free_path;
 928
 929
 930	while (1) {
 931		slot = path->slots[0];
 932		leaf = path->nodes[0];
 933		btrfs_item_key_to_cpu(leaf, &found_key, slot);
 934
 935		if (found_key.type == BTRFS_ROOT_REF_KEY) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 936			ret = add_qgroup_item(trans, quota_root,
 937					      found_key.offset);
 938			if (ret)
 
 939				goto out_free_path;
 
 940
 941			qgroup = add_qgroup_rb(fs_info, found_key.offset);
 
 942			if (IS_ERR(qgroup)) {
 943				ret = PTR_ERR(qgroup);
 
 
 
 
 
 
 
 
 
 
 
 
 944				goto out_free_path;
 945			}
 
 
 
 
 
 
 
 
 946		}
 947		ret = btrfs_next_item(tree_root, path);
 948		if (ret < 0)
 
 949			goto out_free_path;
 
 950		if (ret)
 951			break;
 952	}
 953
 954out_add_root:
 955	btrfs_release_path(path);
 956	ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
 957	if (ret)
 
 958		goto out_free_path;
 
 959
 960	qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
 961	if (IS_ERR(qgroup)) {
 962		ret = PTR_ERR(qgroup);
 
 963		goto out_free_path;
 964	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 965	spin_lock(&fs_info->qgroup_lock);
 966	fs_info->quota_root = quota_root;
 967	fs_info->pending_quota_state = 1;
 
 
 968	spin_unlock(&fs_info->qgroup_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 969out_free_path:
 970	btrfs_free_path(path);
 971out_free_root:
 972	if (ret) {
 973		free_extent_buffer(quota_root->node);
 974		free_extent_buffer(quota_root->commit_root);
 975		kfree(quota_root);
 976	}
 977out:
 978	if (ret) {
 979		ulist_free(fs_info->qgroup_ulist);
 980		fs_info->qgroup_ulist = NULL;
 
 981	}
 982	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 983	return ret;
 984}
 985
 986int btrfs_quota_disable(struct btrfs_trans_handle *trans,
 987			struct btrfs_fs_info *fs_info)
 988{
 989	struct btrfs_root *tree_root = fs_info->tree_root;
 990	struct btrfs_root *quota_root;
 
 991	int ret = 0;
 992
 
 
 
 
 
 
 
 
 
 
 
 
 993	mutex_lock(&fs_info->qgroup_ioctl_lock);
 994	if (!fs_info->quota_root)
 995		goto out;
 996	fs_info->quota_enabled = 0;
 997	fs_info->pending_quota_state = 0;
 998	btrfs_qgroup_wait_for_completion(fs_info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 999	spin_lock(&fs_info->qgroup_lock);
1000	quota_root = fs_info->quota_root;
1001	fs_info->quota_root = NULL;
1002	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
 
 
1003	spin_unlock(&fs_info->qgroup_lock);
1004
1005	btrfs_free_qgroup_config(fs_info);
1006
1007	ret = btrfs_clean_quota_tree(trans, quota_root);
1008	if (ret)
 
1009		goto out;
 
1010
1011	ret = btrfs_del_root(trans, tree_root, &quota_root->root_key);
1012	if (ret)
 
1013		goto out;
 
1014
 
1015	list_del(&quota_root->dirty_list);
 
1016
1017	btrfs_tree_lock(quota_root->node);
1018	clean_tree_block(trans, tree_root->fs_info, quota_root->node);
1019	btrfs_tree_unlock(quota_root->node);
1020	btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
 
 
 
1021
1022	free_extent_buffer(quota_root->node);
1023	free_extent_buffer(quota_root->commit_root);
1024	kfree(quota_root);
1025out:
1026	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
1027	return ret;
1028}
1029
1030static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1031			 struct btrfs_qgroup *qgroup)
1032{
1033	if (list_empty(&qgroup->dirty))
1034		list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1035}
1036
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1037/*
1038 * The easy accounting, if we are adding/removing the only ref for an extent
1039 * then this qgroup and all of the parent qgroups get their refrence and
1040 * exclusive counts adjusted.
 
 
 
 
 
 
 
1041 *
1042 * Caller should hold fs_info->qgroup_lock.
1043 */
1044static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1045				    struct ulist *tmp, u64 ref_root,
1046				    u64 num_bytes, int sign)
1047{
1048	struct btrfs_qgroup *qgroup;
1049	struct btrfs_qgroup_list *glist;
1050	struct ulist_node *unode;
1051	struct ulist_iterator uiter;
1052	int ret = 0;
1053
1054	qgroup = find_qgroup_rb(fs_info, ref_root);
1055	if (!qgroup)
1056		goto out;
1057
1058	qgroup->rfer += sign * num_bytes;
1059	qgroup->rfer_cmpr += sign * num_bytes;
1060
1061	WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1062	qgroup->excl += sign * num_bytes;
1063	qgroup->excl_cmpr += sign * num_bytes;
1064	if (sign > 0)
1065		qgroup->reserved -= num_bytes;
1066
1067	qgroup_dirty(fs_info, qgroup);
1068
1069	/* Get all of the parent groups that contain this qgroup */
1070	list_for_each_entry(glist, &qgroup->groups, next_group) {
1071		ret = ulist_add(tmp, glist->group->qgroupid,
1072				ptr_to_u64(glist->group), GFP_ATOMIC);
1073		if (ret < 0)
1074			goto out;
1075	}
1076
1077	/* Iterate all of the parents and adjust their reference counts */
1078	ULIST_ITER_INIT(&uiter);
1079	while ((unode = ulist_next(tmp, &uiter))) {
1080		qgroup = u64_to_ptr(unode->aux);
1081		qgroup->rfer += sign * num_bytes;
1082		qgroup->rfer_cmpr += sign * num_bytes;
 
1083		WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1084		qgroup->excl += sign * num_bytes;
1085		if (sign > 0)
1086			qgroup->reserved -= num_bytes;
1087		qgroup->excl_cmpr += sign * num_bytes;
 
 
 
 
 
1088		qgroup_dirty(fs_info, qgroup);
1089
1090		/* Add any parents of the parents */
1091		list_for_each_entry(glist, &qgroup->groups, next_group) {
1092			ret = ulist_add(tmp, glist->group->qgroupid,
1093					ptr_to_u64(glist->group), GFP_ATOMIC);
1094			if (ret < 0)
1095				goto out;
1096		}
1097	}
1098	ret = 0;
1099out:
 
1100	return ret;
1101}
1102
1103
1104/*
1105 * Quick path for updating qgroup with only excl refs.
1106 *
1107 * In that case, just update all parent will be enough.
1108 * Or we needs to do a full rescan.
1109 * Caller should also hold fs_info->qgroup_lock.
1110 *
1111 * Return 0 for quick update, return >0 for need to full rescan
1112 * and mark INCONSISTENT flag.
1113 * Return < 0 for other error.
1114 */
1115static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1116				   struct ulist *tmp, u64 src, u64 dst,
1117				   int sign)
1118{
1119	struct btrfs_qgroup *qgroup;
1120	int ret = 1;
1121	int err = 0;
1122
1123	qgroup = find_qgroup_rb(fs_info, src);
1124	if (!qgroup)
1125		goto out;
1126	if (qgroup->excl == qgroup->rfer) {
1127		ret = 0;
1128		err = __qgroup_excl_accounting(fs_info, tmp, dst,
1129					       qgroup->excl, sign);
1130		if (err < 0) {
1131			ret = err;
1132			goto out;
1133		}
1134	}
1135out:
1136	if (ret)
1137		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1138	return ret;
1139}
1140
1141int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
1142			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1143{
1144	struct btrfs_root *quota_root;
1145	struct btrfs_qgroup *parent;
1146	struct btrfs_qgroup *member;
1147	struct btrfs_qgroup_list *list;
1148	struct ulist *tmp;
1149	int ret = 0;
1150
1151	/* Check the level of src and dst first */
1152	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1153		return -EINVAL;
1154
1155	tmp = ulist_alloc(GFP_NOFS);
1156	if (!tmp)
1157		return -ENOMEM;
1158
1159	mutex_lock(&fs_info->qgroup_ioctl_lock);
1160	quota_root = fs_info->quota_root;
1161	if (!quota_root) {
1162		ret = -EINVAL;
1163		goto out;
1164	}
1165	member = find_qgroup_rb(fs_info, src);
1166	parent = find_qgroup_rb(fs_info, dst);
1167	if (!member || !parent) {
1168		ret = -EINVAL;
1169		goto out;
1170	}
1171
1172	/* check if such qgroup relation exist firstly */
1173	list_for_each_entry(list, &member->groups, next_group) {
1174		if (list->group == parent) {
1175			ret = -EEXIST;
1176			goto out;
1177		}
1178	}
1179
1180	ret = add_qgroup_relation_item(trans, quota_root, src, dst);
 
 
 
 
 
1181	if (ret)
1182		goto out;
1183
1184	ret = add_qgroup_relation_item(trans, quota_root, dst, src);
1185	if (ret) {
1186		del_qgroup_relation_item(trans, quota_root, src, dst);
1187		goto out;
1188	}
1189
1190	spin_lock(&fs_info->qgroup_lock);
1191	ret = add_relation_rb(quota_root->fs_info, src, dst);
 
1192	if (ret < 0) {
1193		spin_unlock(&fs_info->qgroup_lock);
1194		goto out;
1195	}
1196	ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1197	spin_unlock(&fs_info->qgroup_lock);
1198out:
 
1199	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1200	ulist_free(tmp);
1201	return ret;
1202}
1203
1204int __del_qgroup_relation(struct btrfs_trans_handle *trans,
1205			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1206{
1207	struct btrfs_root *quota_root;
1208	struct btrfs_qgroup *parent;
1209	struct btrfs_qgroup *member;
1210	struct btrfs_qgroup_list *list;
1211	struct ulist *tmp;
1212	int ret = 0;
1213	int err;
1214
1215	tmp = ulist_alloc(GFP_NOFS);
1216	if (!tmp)
1217		return -ENOMEM;
1218
1219	quota_root = fs_info->quota_root;
1220	if (!quota_root) {
1221		ret = -EINVAL;
1222		goto out;
1223	}
1224
1225	member = find_qgroup_rb(fs_info, src);
1226	parent = find_qgroup_rb(fs_info, dst);
1227	if (!member || !parent) {
1228		ret = -EINVAL;
1229		goto out;
1230	}
 
 
1231
1232	/* check if such qgroup relation exist firstly */
1233	list_for_each_entry(list, &member->groups, next_group) {
1234		if (list->group == parent)
1235			goto exist;
 
 
1236	}
1237	ret = -ENOENT;
1238	goto out;
1239exist:
1240	ret = del_qgroup_relation_item(trans, quota_root, src, dst);
1241	err = del_qgroup_relation_item(trans, quota_root, dst, src);
1242	if (err && !ret)
1243		ret = err;
1244
1245	spin_lock(&fs_info->qgroup_lock);
1246	del_relation_rb(fs_info, src, dst);
1247	ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1248	spin_unlock(&fs_info->qgroup_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1249out:
1250	ulist_free(tmp);
1251	return ret;
1252}
1253
1254int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
1255			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1256{
 
1257	int ret = 0;
1258
1259	mutex_lock(&fs_info->qgroup_ioctl_lock);
1260	ret = __del_qgroup_relation(trans, fs_info, src, dst);
1261	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1262
1263	return ret;
1264}
1265
1266int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
1267			struct btrfs_fs_info *fs_info, u64 qgroupid)
1268{
 
1269	struct btrfs_root *quota_root;
1270	struct btrfs_qgroup *qgroup;
 
1271	int ret = 0;
1272
 
 
 
1273	mutex_lock(&fs_info->qgroup_ioctl_lock);
1274	quota_root = fs_info->quota_root;
1275	if (!quota_root) {
1276		ret = -EINVAL;
1277		goto out;
1278	}
 
1279	qgroup = find_qgroup_rb(fs_info, qgroupid);
1280	if (qgroup) {
1281		ret = -EEXIST;
1282		goto out;
1283	}
1284
 
 
 
 
 
 
1285	ret = add_qgroup_item(trans, quota_root, qgroupid);
1286	if (ret)
1287		goto out;
1288
1289	spin_lock(&fs_info->qgroup_lock);
1290	qgroup = add_qgroup_rb(fs_info, qgroupid);
1291	spin_unlock(&fs_info->qgroup_lock);
 
1292
1293	if (IS_ERR(qgroup))
1294		ret = PTR_ERR(qgroup);
1295out:
1296	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
1297	return ret;
1298}
1299
1300int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
1301			struct btrfs_fs_info *fs_info, u64 qgroupid)
1302{
1303	struct btrfs_root *quota_root;
 
 
 
 
 
 
 
 
 
1304	struct btrfs_qgroup *qgroup;
1305	struct btrfs_qgroup_list *list;
1306	int ret = 0;
1307
1308	mutex_lock(&fs_info->qgroup_ioctl_lock);
1309	quota_root = fs_info->quota_root;
1310	if (!quota_root) {
1311		ret = -EINVAL;
1312		goto out;
1313	}
1314
1315	qgroup = find_qgroup_rb(fs_info, qgroupid);
1316	if (!qgroup) {
1317		ret = -ENOENT;
1318		goto out;
1319	} else {
1320		/* check if there are no children of this qgroup */
1321		if (!list_empty(&qgroup->members)) {
1322			ret = -EBUSY;
1323			goto out;
1324		}
1325	}
1326	ret = del_qgroup_item(trans, quota_root, qgroupid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1327
1328	while (!list_empty(&qgroup->groups)) {
1329		list = list_first_entry(&qgroup->groups,
1330					struct btrfs_qgroup_list, next_group);
1331		ret = __del_qgroup_relation(trans, fs_info,
1332					   qgroupid,
1333					   list->group->qgroupid);
1334		if (ret)
1335			goto out;
1336	}
1337
1338	spin_lock(&fs_info->qgroup_lock);
1339	del_qgroup_rb(quota_root->fs_info, qgroupid);
1340	spin_unlock(&fs_info->qgroup_lock);
 
 
 
 
 
 
 
 
1341out:
1342	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1343	return ret;
1344}
1345
1346int btrfs_limit_qgroup(struct btrfs_trans_handle *trans,
1347		       struct btrfs_fs_info *fs_info, u64 qgroupid,
1348		       struct btrfs_qgroup_limit *limit)
1349{
1350	struct btrfs_root *quota_root;
1351	struct btrfs_qgroup *qgroup;
1352	int ret = 0;
1353	/* Sometimes we would want to clear the limit on this qgroup.
1354	 * To meet this requirement, we treat the -1 as a special value
1355	 * which tell kernel to clear the limit on this qgroup.
1356	 */
1357	const u64 CLEAR_VALUE = -1;
1358
1359	mutex_lock(&fs_info->qgroup_ioctl_lock);
1360	quota_root = fs_info->quota_root;
1361	if (!quota_root) {
1362		ret = -EINVAL;
1363		goto out;
1364	}
1365
1366	qgroup = find_qgroup_rb(fs_info, qgroupid);
1367	if (!qgroup) {
1368		ret = -ENOENT;
1369		goto out;
1370	}
1371
1372	spin_lock(&fs_info->qgroup_lock);
1373	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1374		if (limit->max_rfer == CLEAR_VALUE) {
1375			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1376			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1377			qgroup->max_rfer = 0;
1378		} else {
1379			qgroup->max_rfer = limit->max_rfer;
1380		}
1381	}
1382	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1383		if (limit->max_excl == CLEAR_VALUE) {
1384			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1385			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1386			qgroup->max_excl = 0;
1387		} else {
1388			qgroup->max_excl = limit->max_excl;
1389		}
1390	}
1391	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1392		if (limit->rsv_rfer == CLEAR_VALUE) {
1393			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1394			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1395			qgroup->rsv_rfer = 0;
1396		} else {
1397			qgroup->rsv_rfer = limit->rsv_rfer;
1398		}
1399	}
1400	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1401		if (limit->rsv_excl == CLEAR_VALUE) {
1402			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1403			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1404			qgroup->rsv_excl = 0;
1405		} else {
1406			qgroup->rsv_excl = limit->rsv_excl;
1407		}
1408	}
1409	qgroup->lim_flags |= limit->flags;
1410
1411	spin_unlock(&fs_info->qgroup_lock);
1412
1413	ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1414	if (ret) {
1415		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1416		btrfs_info(fs_info, "unable to update quota limit for %llu",
1417		       qgroupid);
1418	}
1419
1420out:
1421	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1422	return ret;
1423}
1424
1425int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans,
1426					 struct btrfs_fs_info *fs_info)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1427{
 
1428	struct btrfs_qgroup_extent_record *record;
1429	struct btrfs_delayed_ref_root *delayed_refs;
1430	struct rb_node *node;
1431	u64 qgroup_to_skip;
1432	int ret = 0;
 
 
 
 
1433
1434	delayed_refs = &trans->transaction->delayed_refs;
1435	qgroup_to_skip = delayed_refs->qgroup_to_skip;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1436
1437	/*
1438	 * No need to do lock, since this function will only be called in
1439	 * btrfs_commmit_transaction().
1440	 */
1441	node = rb_first(&delayed_refs->dirty_extent_root);
1442	while (node) {
1443		record = rb_entry(node, struct btrfs_qgroup_extent_record,
1444				  node);
1445		ret = btrfs_find_all_roots(NULL, fs_info, record->bytenr, 0,
1446					   &record->old_roots);
 
 
 
 
 
 
1447		if (ret < 0)
1448			break;
1449		if (qgroup_to_skip)
1450			ulist_del(record->old_roots, qgroup_to_skip, 0);
1451		node = rb_next(node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1452	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1453	return ret;
1454}
1455
1456struct btrfs_qgroup_extent_record
1457*btrfs_qgroup_insert_dirty_extent(struct btrfs_delayed_ref_root *delayed_refs,
1458				  struct btrfs_qgroup_extent_record *record)
 
 
 
 
 
 
 
 
 
 
1459{
1460	struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1461	struct rb_node *parent_node = NULL;
1462	struct btrfs_qgroup_extent_record *entry;
1463	u64 bytenr = record->bytenr;
 
 
1464
1465	assert_spin_locked(&delayed_refs->lock);
1466	trace_btrfs_qgroup_insert_dirty_extent(record);
1467
1468	while (*p) {
1469		parent_node = *p;
1470		entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1471				 node);
1472		if (bytenr < entry->bytenr)
1473			p = &(*p)->rb_left;
1474		else if (bytenr > entry->bytenr)
1475			p = &(*p)->rb_right;
1476		else
1477			return entry;
 
 
 
 
 
 
 
 
1478	}
1479
1480	rb_link_node(&record->node, parent_node, p);
1481	rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1482	return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1483}
1484
1485#define UPDATE_NEW	0
1486#define UPDATE_OLD	1
1487/*
1488 * Walk all of the roots that points to the bytenr and adjust their refcnts.
1489 */
1490static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
1491				struct ulist *roots, struct ulist *tmp,
1492				struct ulist *qgroups, u64 seq, int update_old)
1493{
1494	struct ulist_node *unode;
1495	struct ulist_iterator uiter;
1496	struct ulist_node *tmp_unode;
1497	struct ulist_iterator tmp_uiter;
1498	struct btrfs_qgroup *qg;
1499	int ret = 0;
1500
1501	if (!roots)
1502		return 0;
1503	ULIST_ITER_INIT(&uiter);
1504	while ((unode = ulist_next(roots, &uiter))) {
 
 
1505		qg = find_qgroup_rb(fs_info, unode->val);
1506		if (!qg)
1507			continue;
1508
1509		ulist_reinit(tmp);
1510		ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
1511				GFP_ATOMIC);
1512		if (ret < 0)
1513			return ret;
1514		ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg), GFP_ATOMIC);
1515		if (ret < 0)
1516			return ret;
1517		ULIST_ITER_INIT(&tmp_uiter);
1518		while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
1519			struct btrfs_qgroup_list *glist;
1520
1521			qg = u64_to_ptr(tmp_unode->aux);
1522			if (update_old)
1523				btrfs_qgroup_update_old_refcnt(qg, seq, 1);
1524			else
1525				btrfs_qgroup_update_new_refcnt(qg, seq, 1);
 
1526			list_for_each_entry(glist, &qg->groups, next_group) {
1527				ret = ulist_add(qgroups, glist->group->qgroupid,
1528						ptr_to_u64(glist->group),
1529						GFP_ATOMIC);
1530				if (ret < 0)
1531					return ret;
1532				ret = ulist_add(tmp, glist->group->qgroupid,
1533						ptr_to_u64(glist->group),
1534						GFP_ATOMIC);
1535				if (ret < 0)
1536					return ret;
1537			}
1538		}
 
1539	}
1540	return 0;
1541}
1542
1543/*
1544 * Update qgroup rfer/excl counters.
1545 * Rfer update is easy, codes can explain themselves.
1546 *
1547 * Excl update is tricky, the update is split into 2 part.
1548 * Part 1: Possible exclusive <-> sharing detect:
1549 *	|	A	|	!A	|
1550 *  -------------------------------------
1551 *  B	|	*	|	-	|
1552 *  -------------------------------------
1553 *  !B	|	+	|	**	|
1554 *  -------------------------------------
1555 *
1556 * Conditions:
1557 * A:	cur_old_roots < nr_old_roots	(not exclusive before)
1558 * !A:	cur_old_roots == nr_old_roots	(possible exclusive before)
1559 * B:	cur_new_roots < nr_new_roots	(not exclusive now)
1560 * !B:	cur_new_roots == nr_new_roots	(possible exclsuive now)
1561 *
1562 * Results:
1563 * +: Possible sharing -> exclusive	-: Possible exclusive -> sharing
1564 * *: Definitely not changed.		**: Possible unchanged.
1565 *
1566 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
1567 *
1568 * To make the logic clear, we first use condition A and B to split
1569 * combination into 4 results.
1570 *
1571 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
1572 * only on variant maybe 0.
1573 *
1574 * Lastly, check result **, since there are 2 variants maybe 0, split them
1575 * again(2x2).
1576 * But this time we don't need to consider other things, the codes and logic
1577 * is easy to understand now.
1578 */
1579static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
1580				  struct ulist *qgroups,
1581				  u64 nr_old_roots,
1582				  u64 nr_new_roots,
1583				  u64 num_bytes, u64 seq)
1584{
1585	struct ulist_node *unode;
1586	struct ulist_iterator uiter;
1587	struct btrfs_qgroup *qg;
1588	u64 cur_new_count, cur_old_count;
1589
1590	ULIST_ITER_INIT(&uiter);
1591	while ((unode = ulist_next(qgroups, &uiter))) {
1592		bool dirty = false;
1593
1594		qg = u64_to_ptr(unode->aux);
1595		cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
1596		cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
1597
1598		trace_qgroup_update_counters(qg->qgroupid, cur_old_count,
1599					     cur_new_count);
1600
1601		/* Rfer update part */
1602		if (cur_old_count == 0 && cur_new_count > 0) {
1603			qg->rfer += num_bytes;
1604			qg->rfer_cmpr += num_bytes;
1605			dirty = true;
1606		}
1607		if (cur_old_count > 0 && cur_new_count == 0) {
1608			qg->rfer -= num_bytes;
1609			qg->rfer_cmpr -= num_bytes;
1610			dirty = true;
1611		}
1612
1613		/* Excl update part */
1614		/* Exclusive/none -> shared case */
1615		if (cur_old_count == nr_old_roots &&
1616		    cur_new_count < nr_new_roots) {
1617			/* Exclusive -> shared */
1618			if (cur_old_count != 0) {
1619				qg->excl -= num_bytes;
1620				qg->excl_cmpr -= num_bytes;
1621				dirty = true;
1622			}
1623		}
1624
1625		/* Shared -> exclusive/none case */
1626		if (cur_old_count < nr_old_roots &&
1627		    cur_new_count == nr_new_roots) {
1628			/* Shared->exclusive */
1629			if (cur_new_count != 0) {
1630				qg->excl += num_bytes;
1631				qg->excl_cmpr += num_bytes;
1632				dirty = true;
1633			}
1634		}
1635
1636		/* Exclusive/none -> exclusive/none case */
1637		if (cur_old_count == nr_old_roots &&
1638		    cur_new_count == nr_new_roots) {
1639			if (cur_old_count == 0) {
1640				/* None -> exclusive/none */
1641
1642				if (cur_new_count != 0) {
1643					/* None -> exclusive */
1644					qg->excl += num_bytes;
1645					qg->excl_cmpr += num_bytes;
1646					dirty = true;
1647				}
1648				/* None -> none, nothing changed */
1649			} else {
1650				/* Exclusive -> exclusive/none */
1651
1652				if (cur_new_count == 0) {
1653					/* Exclusive -> none */
1654					qg->excl -= num_bytes;
1655					qg->excl_cmpr -= num_bytes;
1656					dirty = true;
1657				}
1658				/* Exclusive -> exclusive, nothing changed */
1659			}
1660		}
1661
1662		if (dirty)
1663			qgroup_dirty(fs_info, qg);
1664	}
1665	return 0;
1666}
1667
1668int
1669btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans,
1670			    struct btrfs_fs_info *fs_info,
1671			    u64 bytenr, u64 num_bytes,
1672			    struct ulist *old_roots, struct ulist *new_roots)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1673{
1674	struct ulist *qgroups = NULL;
1675	struct ulist *tmp = NULL;
1676	u64 seq;
1677	u64 nr_new_roots = 0;
1678	u64 nr_old_roots = 0;
1679	int ret = 0;
1680
1681	if (new_roots)
 
 
 
 
 
 
 
 
 
 
1682		nr_new_roots = new_roots->nnodes;
1683	if (old_roots)
 
 
 
1684		nr_old_roots = old_roots->nnodes;
 
1685
1686	if (!fs_info->quota_enabled)
 
1687		goto out_free;
1688	BUG_ON(!fs_info->quota_root);
1689
1690	trace_btrfs_qgroup_account_extent(bytenr, num_bytes, nr_old_roots,
1691					  nr_new_roots);
1692
1693	qgroups = ulist_alloc(GFP_NOFS);
1694	if (!qgroups) {
1695		ret = -ENOMEM;
1696		goto out_free;
1697	}
1698	tmp = ulist_alloc(GFP_NOFS);
1699	if (!tmp) {
1700		ret = -ENOMEM;
1701		goto out_free;
1702	}
1703
1704	mutex_lock(&fs_info->qgroup_rescan_lock);
1705	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
1706		if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
1707			mutex_unlock(&fs_info->qgroup_rescan_lock);
1708			ret = 0;
1709			goto out_free;
1710		}
1711	}
1712	mutex_unlock(&fs_info->qgroup_rescan_lock);
1713
1714	spin_lock(&fs_info->qgroup_lock);
1715	seq = fs_info->qgroup_seq;
1716
1717	/* Update old refcnts using old_roots */
1718	ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
1719				   UPDATE_OLD);
1720	if (ret < 0)
1721		goto out;
1722
1723	/* Update new refcnts using new_roots */
1724	ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
1725				   UPDATE_NEW);
1726	if (ret < 0)
1727		goto out;
1728
1729	qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
1730			       num_bytes, seq);
1731
1732	/*
 
 
 
 
 
 
 
1733	 * Bump qgroup_seq to avoid seq overlap
1734	 */
1735	fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
1736out:
1737	spin_unlock(&fs_info->qgroup_lock);
1738out_free:
1739	ulist_free(tmp);
1740	ulist_free(qgroups);
1741	ulist_free(old_roots);
1742	ulist_free(new_roots);
1743	return ret;
1744}
1745
1746int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans,
1747				 struct btrfs_fs_info *fs_info)
1748{
 
1749	struct btrfs_qgroup_extent_record *record;
1750	struct btrfs_delayed_ref_root *delayed_refs;
1751	struct ulist *new_roots = NULL;
1752	struct rb_node *node;
 
1753	u64 qgroup_to_skip;
1754	int ret = 0;
1755
 
 
 
1756	delayed_refs = &trans->transaction->delayed_refs;
1757	qgroup_to_skip = delayed_refs->qgroup_to_skip;
1758	while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
1759		record = rb_entry(node, struct btrfs_qgroup_extent_record,
1760				  node);
1761
1762		trace_btrfs_qgroup_account_extents(record);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1763
1764		if (!ret) {
1765			/*
1766			 * Use (u64)-1 as time_seq to do special search, which
1767			 * doesn't lock tree or delayed_refs and search current
1768			 * root. It's safe inside commit_transaction().
1769			 */
1770			ret = btrfs_find_all_roots(trans, fs_info,
1771					record->bytenr, (u64)-1, &new_roots);
 
1772			if (ret < 0)
1773				goto cleanup;
1774			if (qgroup_to_skip)
 
1775				ulist_del(new_roots, qgroup_to_skip, 0);
1776			ret = btrfs_qgroup_account_extent(trans, fs_info,
1777					record->bytenr, record->num_bytes,
1778					record->old_roots, new_roots);
 
 
 
 
1779			record->old_roots = NULL;
1780			new_roots = NULL;
1781		}
 
 
 
 
 
1782cleanup:
1783		ulist_free(record->old_roots);
1784		ulist_free(new_roots);
1785		new_roots = NULL;
1786		rb_erase(node, &delayed_refs->dirty_extent_root);
1787		kfree(record);
1788
1789	}
 
 
1790	return ret;
1791}
1792
1793/*
1794 * called from commit_transaction. Writes all changed qgroups to disk.
 
1795 */
1796int btrfs_run_qgroups(struct btrfs_trans_handle *trans,
1797		      struct btrfs_fs_info *fs_info)
1798{
1799	struct btrfs_root *quota_root = fs_info->quota_root;
1800	int ret = 0;
1801	int start_rescan_worker = 0;
1802
1803	if (!quota_root)
1804		goto out;
1805
1806	if (!fs_info->quota_enabled && fs_info->pending_quota_state)
1807		start_rescan_worker = 1;
 
 
 
 
 
1808
1809	fs_info->quota_enabled = fs_info->pending_quota_state;
 
1810
1811	spin_lock(&fs_info->qgroup_lock);
1812	while (!list_empty(&fs_info->dirty_qgroups)) {
1813		struct btrfs_qgroup *qgroup;
1814		qgroup = list_first_entry(&fs_info->dirty_qgroups,
1815					  struct btrfs_qgroup, dirty);
1816		list_del_init(&qgroup->dirty);
1817		spin_unlock(&fs_info->qgroup_lock);
1818		ret = update_qgroup_info_item(trans, quota_root, qgroup);
1819		if (ret)
1820			fs_info->qgroup_flags |=
1821					BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1822		ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1823		if (ret)
1824			fs_info->qgroup_flags |=
1825					BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1826		spin_lock(&fs_info->qgroup_lock);
1827	}
1828	if (fs_info->quota_enabled)
1829		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
1830	else
1831		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1832	spin_unlock(&fs_info->qgroup_lock);
1833
1834	ret = update_qgroup_status_item(trans, fs_info, quota_root);
1835	if (ret)
1836		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1837
1838	if (!ret && start_rescan_worker) {
1839		ret = qgroup_rescan_init(fs_info, 0, 1);
1840		if (!ret) {
1841			qgroup_rescan_zero_tracking(fs_info);
1842			btrfs_queue_work(fs_info->qgroup_rescan_workers,
1843					 &fs_info->qgroup_rescan_work);
 
 
 
 
 
 
 
 
 
 
 
 
1844		}
1845		ret = 0;
1846	}
 
 
1847
1848out:
 
 
 
 
 
 
 
 
 
 
1849
1850	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1851}
1852
1853/*
1854 * Copy the acounting information between qgroups. This is necessary
1855 * when a snapshot or a subvolume is created. Throwing an error will
1856 * cause a transaction abort so we take extra care here to only error
1857 * when a readonly fs is a reasonable outcome.
1858 */
1859int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans,
1860			 struct btrfs_fs_info *fs_info, u64 srcid, u64 objectid,
1861			 struct btrfs_qgroup_inherit *inherit)
1862{
1863	int ret = 0;
1864	int i;
1865	u64 *i_qgroups;
1866	struct btrfs_root *quota_root = fs_info->quota_root;
 
 
1867	struct btrfs_qgroup *srcgroup;
1868	struct btrfs_qgroup *dstgroup;
 
 
 
 
1869	u32 level_size = 0;
1870	u64 nums;
1871
1872	mutex_lock(&fs_info->qgroup_ioctl_lock);
1873	if (!fs_info->quota_enabled)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1874		goto out;
1875
 
1876	if (!quota_root) {
1877		ret = -EINVAL;
1878		goto out;
1879	}
1880
 
 
 
 
 
 
 
1881	if (inherit) {
1882		i_qgroups = (u64 *)(inherit + 1);
1883		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
1884		       2 * inherit->num_excl_copies;
1885		for (i = 0; i < nums; ++i) {
1886			srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
1887
1888			/*
1889			 * Zero out invalid groups so we can ignore
1890			 * them later.
1891			 */
1892			if (!srcgroup ||
1893			    ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
1894				*i_qgroups = 0ULL;
1895
1896			++i_qgroups;
1897		}
1898	}
1899
1900	/*
1901	 * create a tracking group for the subvol itself
1902	 */
1903	ret = add_qgroup_item(trans, quota_root, objectid);
1904	if (ret)
1905		goto out;
1906
1907	if (srcid) {
1908		struct btrfs_root *srcroot;
1909		struct btrfs_key srckey;
1910
1911		srckey.objectid = srcid;
1912		srckey.type = BTRFS_ROOT_ITEM_KEY;
1913		srckey.offset = (u64)-1;
1914		srcroot = btrfs_read_fs_root_no_name(fs_info, &srckey);
1915		if (IS_ERR(srcroot)) {
1916			ret = PTR_ERR(srcroot);
1917			goto out;
1918		}
1919
1920		rcu_read_lock();
1921		level_size = srcroot->nodesize;
1922		rcu_read_unlock();
1923	}
1924
1925	/*
1926	 * add qgroup to all inherited groups
1927	 */
1928	if (inherit) {
1929		i_qgroups = (u64 *)(inherit + 1);
1930		for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
1931			if (*i_qgroups == 0)
1932				continue;
1933			ret = add_qgroup_relation_item(trans, quota_root,
1934						       objectid, *i_qgroups);
1935			if (ret && ret != -EEXIST)
1936				goto out;
1937			ret = add_qgroup_relation_item(trans, quota_root,
1938						       *i_qgroups, objectid);
1939			if (ret && ret != -EEXIST)
1940				goto out;
1941		}
1942		ret = 0;
1943	}
1944
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1945
1946	spin_lock(&fs_info->qgroup_lock);
1947
1948	dstgroup = add_qgroup_rb(fs_info, objectid);
1949	if (IS_ERR(dstgroup)) {
1950		ret = PTR_ERR(dstgroup);
1951		goto unlock;
1952	}
1953
1954	if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
1955		dstgroup->lim_flags = inherit->lim.flags;
1956		dstgroup->max_rfer = inherit->lim.max_rfer;
1957		dstgroup->max_excl = inherit->lim.max_excl;
1958		dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
1959		dstgroup->rsv_excl = inherit->lim.rsv_excl;
1960
1961		ret = update_qgroup_limit_item(trans, quota_root, dstgroup);
1962		if (ret) {
1963			fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1964			btrfs_info(fs_info, "unable to update quota limit for %llu",
1965			       dstgroup->qgroupid);
1966			goto unlock;
1967		}
1968	}
1969
1970	if (srcid) {
1971		srcgroup = find_qgroup_rb(fs_info, srcid);
1972		if (!srcgroup)
1973			goto unlock;
1974
1975		/*
1976		 * We call inherit after we clone the root in order to make sure
1977		 * our counts don't go crazy, so at this point the only
1978		 * difference between the two roots should be the root node.
1979		 */
 
1980		dstgroup->rfer = srcgroup->rfer;
1981		dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
1982		dstgroup->excl = level_size;
1983		dstgroup->excl_cmpr = level_size;
1984		srcgroup->excl = level_size;
1985		srcgroup->excl_cmpr = level_size;
1986
1987		/* inherit the limit info */
1988		dstgroup->lim_flags = srcgroup->lim_flags;
1989		dstgroup->max_rfer = srcgroup->max_rfer;
1990		dstgroup->max_excl = srcgroup->max_excl;
1991		dstgroup->rsv_rfer = srcgroup->rsv_rfer;
1992		dstgroup->rsv_excl = srcgroup->rsv_excl;
1993
1994		qgroup_dirty(fs_info, dstgroup);
1995		qgroup_dirty(fs_info, srcgroup);
 
 
 
 
 
 
 
1996	}
1997
1998	if (!inherit)
1999		goto unlock;
2000
2001	i_qgroups = (u64 *)(inherit + 1);
2002	for (i = 0; i < inherit->num_qgroups; ++i) {
2003		if (*i_qgroups) {
2004			ret = add_relation_rb(quota_root->fs_info, objectid,
2005					      *i_qgroups);
 
2006			if (ret)
2007				goto unlock;
2008		}
 
 
 
 
 
 
 
 
 
2009		++i_qgroups;
2010	}
2011
2012	for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
2013		struct btrfs_qgroup *src;
2014		struct btrfs_qgroup *dst;
2015
2016		if (!i_qgroups[0] || !i_qgroups[1])
2017			continue;
2018
2019		src = find_qgroup_rb(fs_info, i_qgroups[0]);
2020		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2021
2022		if (!src || !dst) {
2023			ret = -EINVAL;
2024			goto unlock;
2025		}
2026
2027		dst->rfer = src->rfer - level_size;
2028		dst->rfer_cmpr = src->rfer_cmpr - level_size;
 
 
 
2029	}
2030	for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
2031		struct btrfs_qgroup *src;
2032		struct btrfs_qgroup *dst;
2033
2034		if (!i_qgroups[0] || !i_qgroups[1])
2035			continue;
2036
2037		src = find_qgroup_rb(fs_info, i_qgroups[0]);
2038		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2039
2040		if (!src || !dst) {
2041			ret = -EINVAL;
2042			goto unlock;
2043		}
2044
2045		dst->excl = src->excl + level_size;
2046		dst->excl_cmpr = src->excl_cmpr + level_size;
 
2047	}
2048
2049unlock:
2050	spin_unlock(&fs_info->qgroup_lock);
 
 
2051out:
2052	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
 
 
 
 
 
 
2053	return ret;
2054}
2055
2056static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2057{
2058	struct btrfs_root *quota_root;
2059	struct btrfs_qgroup *qgroup;
2060	struct btrfs_fs_info *fs_info = root->fs_info;
2061	u64 ref_root = root->root_key.objectid;
2062	int ret = 0;
2063	struct ulist_node *unode;
2064	struct ulist_iterator uiter;
2065
2066	if (!is_fstree(ref_root))
2067		return 0;
2068
2069	if (num_bytes == 0)
2070		return 0;
2071
 
 
 
 
2072	spin_lock(&fs_info->qgroup_lock);
2073	quota_root = fs_info->quota_root;
2074	if (!quota_root)
2075		goto out;
2076
2077	qgroup = find_qgroup_rb(fs_info, ref_root);
2078	if (!qgroup)
2079		goto out;
2080
2081	/*
2082	 * in a first step, we check all affected qgroups if any limits would
2083	 * be exceeded
2084	 */
2085	ulist_reinit(fs_info->qgroup_ulist);
2086	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2087			(uintptr_t)qgroup, GFP_ATOMIC);
2088	if (ret < 0)
2089		goto out;
2090	ULIST_ITER_INIT(&uiter);
2091	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2092		struct btrfs_qgroup *qg;
2093		struct btrfs_qgroup_list *glist;
2094
2095		qg = u64_to_ptr(unode->aux);
2096
2097		if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2098		    qg->reserved + (s64)qg->rfer + num_bytes >
2099		    qg->max_rfer) {
2100			ret = -EDQUOT;
2101			goto out;
2102		}
2103
2104		if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2105		    qg->reserved + (s64)qg->excl + num_bytes >
2106		    qg->max_excl) {
2107			ret = -EDQUOT;
2108			goto out;
2109		}
2110
2111		list_for_each_entry(glist, &qg->groups, next_group) {
2112			ret = ulist_add(fs_info->qgroup_ulist,
2113					glist->group->qgroupid,
2114					(uintptr_t)glist->group, GFP_ATOMIC);
2115			if (ret < 0)
2116				goto out;
2117		}
2118	}
 
2119	ret = 0;
2120	/*
2121	 * no limits exceeded, now record the reservation into all qgroups
2122	 */
2123	ULIST_ITER_INIT(&uiter);
2124	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2125		struct btrfs_qgroup *qg;
2126
2127		qg = u64_to_ptr(unode->aux);
2128
2129		qg->reserved += num_bytes;
2130	}
2131
2132out:
 
2133	spin_unlock(&fs_info->qgroup_lock);
2134	return ret;
2135}
2136
 
 
 
 
 
 
 
 
 
2137void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
2138			       u64 ref_root, u64 num_bytes)
 
2139{
2140	struct btrfs_root *quota_root;
2141	struct btrfs_qgroup *qgroup;
2142	struct ulist_node *unode;
2143	struct ulist_iterator uiter;
2144	int ret = 0;
2145
2146	if (!is_fstree(ref_root))
2147		return;
2148
2149	if (num_bytes == 0)
2150		return;
2151
 
 
 
 
2152	spin_lock(&fs_info->qgroup_lock);
2153
2154	quota_root = fs_info->quota_root;
2155	if (!quota_root)
2156		goto out;
2157
2158	qgroup = find_qgroup_rb(fs_info, ref_root);
2159	if (!qgroup)
2160		goto out;
2161
2162	ulist_reinit(fs_info->qgroup_ulist);
2163	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2164			(uintptr_t)qgroup, GFP_ATOMIC);
2165	if (ret < 0)
2166		goto out;
2167	ULIST_ITER_INIT(&uiter);
2168	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2169		struct btrfs_qgroup *qg;
2170		struct btrfs_qgroup_list *glist;
2171
2172		qg = u64_to_ptr(unode->aux);
2173
2174		qg->reserved -= num_bytes;
 
 
2175
2176		list_for_each_entry(glist, &qg->groups, next_group) {
2177			ret = ulist_add(fs_info->qgroup_ulist,
2178					glist->group->qgroupid,
2179					(uintptr_t)glist->group, GFP_ATOMIC);
2180			if (ret < 0)
2181				goto out;
2182		}
2183	}
2184
2185out:
 
2186	spin_unlock(&fs_info->qgroup_lock);
2187}
2188
2189static inline void qgroup_free(struct btrfs_root *root, u64 num_bytes)
2190{
2191	return btrfs_qgroup_free_refroot(root->fs_info, root->objectid,
2192					 num_bytes);
2193}
2194void assert_qgroups_uptodate(struct btrfs_trans_handle *trans)
2195{
2196	if (list_empty(&trans->qgroup_ref_list) && !trans->delayed_ref_elem.seq)
2197		return;
2198	btrfs_err(trans->root->fs_info,
2199		"qgroups not uptodate in trans handle %p:  list is%s empty, "
2200		"seq is %#x.%x",
2201		trans, list_empty(&trans->qgroup_ref_list) ? "" : " not",
2202		(u32)(trans->delayed_ref_elem.seq >> 32),
2203		(u32)trans->delayed_ref_elem.seq);
2204	BUG();
2205}
2206
2207/*
2208 * returns < 0 on error, 0 when more leafs are to be scanned.
2209 * returns 1 when done.
2210 */
2211static int
2212qgroup_rescan_leaf(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
2213		   struct btrfs_trans_handle *trans)
2214{
 
 
2215	struct btrfs_key found;
2216	struct extent_buffer *scratch_leaf = NULL;
2217	struct ulist *roots = NULL;
2218	struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
2219	u64 num_bytes;
 
2220	int slot;
2221	int ret;
2222
 
 
 
2223	mutex_lock(&fs_info->qgroup_rescan_lock);
2224	ret = btrfs_search_slot_for_read(fs_info->extent_root,
 
 
2225					 &fs_info->qgroup_rescan_progress,
2226					 path, 1, 0);
2227
2228	pr_debug("current progress key (%llu %u %llu), search_slot ret %d\n",
2229		 fs_info->qgroup_rescan_progress.objectid,
2230		 fs_info->qgroup_rescan_progress.type,
2231		 fs_info->qgroup_rescan_progress.offset, ret);
 
2232
2233	if (ret) {
2234		/*
2235		 * The rescan is about to end, we will not be scanning any
2236		 * further blocks. We cannot unset the RESCAN flag here, because
2237		 * we want to commit the transaction if everything went well.
2238		 * To make the live accounting work in this phase, we set our
2239		 * scan progress pointer such that every real extent objectid
2240		 * will be smaller.
2241		 */
2242		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
2243		btrfs_release_path(path);
2244		mutex_unlock(&fs_info->qgroup_rescan_lock);
2245		return ret;
2246	}
 
2247
2248	btrfs_item_key_to_cpu(path->nodes[0], &found,
2249			      btrfs_header_nritems(path->nodes[0]) - 1);
2250	fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
2251
2252	btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2253	scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
2254	if (!scratch_leaf) {
2255		ret = -ENOMEM;
2256		mutex_unlock(&fs_info->qgroup_rescan_lock);
2257		goto out;
2258	}
2259	extent_buffer_get(scratch_leaf);
2260	btrfs_tree_read_lock(scratch_leaf);
2261	btrfs_set_lock_blocking_rw(scratch_leaf, BTRFS_READ_LOCK);
2262	slot = path->slots[0];
2263	btrfs_release_path(path);
2264	mutex_unlock(&fs_info->qgroup_rescan_lock);
2265
2266	for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
 
 
2267		btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
2268		if (found.type != BTRFS_EXTENT_ITEM_KEY &&
2269		    found.type != BTRFS_METADATA_ITEM_KEY)
2270			continue;
2271		if (found.type == BTRFS_METADATA_ITEM_KEY)
2272			num_bytes = fs_info->extent_root->nodesize;
2273		else
2274			num_bytes = found.offset;
2275
2276		ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
2277					   &roots);
 
 
2278		if (ret < 0)
2279			goto out;
2280		/* For rescan, just pass old_roots as NULL */
2281		ret = btrfs_qgroup_account_extent(trans, fs_info,
2282				found.objectid, num_bytes, NULL, roots);
2283		if (ret < 0)
2284			goto out;
2285	}
2286out:
2287	if (scratch_leaf) {
2288		btrfs_tree_read_unlock_blocking(scratch_leaf);
2289		free_extent_buffer(scratch_leaf);
2290	}
2291	btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2292
 
 
 
 
2293	return ret;
2294}
2295
 
 
 
 
 
 
 
 
 
 
 
 
 
2296static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
2297{
2298	struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
2299						     qgroup_rescan_work);
2300	struct btrfs_path *path;
2301	struct btrfs_trans_handle *trans = NULL;
2302	int err = -ENOMEM;
2303	int ret = 0;
 
 
 
 
 
2304
2305	path = btrfs_alloc_path();
2306	if (!path)
2307		goto out;
 
 
 
 
 
 
2308
2309	err = 0;
2310	while (!err && !btrfs_fs_closing(fs_info)) {
2311		trans = btrfs_start_transaction(fs_info->fs_root, 0);
2312		if (IS_ERR(trans)) {
2313			err = PTR_ERR(trans);
2314			break;
2315		}
2316		if (!fs_info->quota_enabled) {
2317			err = -EINTR;
2318		} else {
2319			err = qgroup_rescan_leaf(fs_info, path, trans);
2320		}
2321		if (err > 0)
2322			btrfs_commit_transaction(trans, fs_info->fs_root);
2323		else
2324			btrfs_end_transaction(trans, fs_info->fs_root);
2325	}
2326
2327out:
2328	btrfs_free_path(path);
2329
2330	mutex_lock(&fs_info->qgroup_rescan_lock);
2331	if (!btrfs_fs_closing(fs_info))
2332		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2333
2334	if (err > 0 &&
2335	    fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
2336		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2337	} else if (err < 0) {
2338		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2339	}
2340	mutex_unlock(&fs_info->qgroup_rescan_lock);
2341
2342	/*
2343	 * only update status, since the previous part has alreay updated the
2344	 * qgroup info.
 
 
 
2345	 */
2346	trans = btrfs_start_transaction(fs_info->quota_root, 1);
2347	if (IS_ERR(trans)) {
2348		err = PTR_ERR(trans);
2349		btrfs_err(fs_info,
2350			  "fail to start transaction for status update: %d\n",
2351			  err);
2352		goto done;
 
 
 
 
2353	}
2354	ret = update_qgroup_status_item(trans, fs_info, fs_info->quota_root);
2355	if (ret < 0) {
2356		err = ret;
2357		btrfs_err(fs_info, "fail to update qgroup status: %d\n", err);
 
 
 
 
 
 
 
 
2358	}
2359	btrfs_end_transaction(trans, fs_info->quota_root);
 
 
 
 
 
 
2360
2361	if (btrfs_fs_closing(fs_info)) {
 
 
2362		btrfs_info(fs_info, "qgroup scan paused");
 
 
2363	} else if (err >= 0) {
2364		btrfs_info(fs_info, "qgroup scan completed%s",
2365			err > 0 ? " (inconsistency flag cleared)" : "");
2366	} else {
2367		btrfs_err(fs_info, "qgroup scan failed with %d", err);
2368	}
2369
2370done:
2371	complete_all(&fs_info->qgroup_rescan_completion);
2372}
2373
2374/*
2375 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
2376 * memory required for the rescan context.
2377 */
2378static int
2379qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
2380		   int init_flags)
2381{
2382	int ret = 0;
2383
2384	if (!init_flags &&
2385	    (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ||
2386	     !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))) {
2387		ret = -EINVAL;
2388		goto err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2389	}
2390
2391	mutex_lock(&fs_info->qgroup_rescan_lock);
2392	spin_lock(&fs_info->qgroup_lock);
2393
2394	if (init_flags) {
2395		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
 
 
2396			ret = -EINPROGRESS;
2397		else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
 
 
 
2398			ret = -EINVAL;
 
 
 
 
2399
2400		if (ret) {
2401			spin_unlock(&fs_info->qgroup_lock);
2402			mutex_unlock(&fs_info->qgroup_rescan_lock);
2403			goto err;
2404		}
2405		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2406	}
2407
2408	memset(&fs_info->qgroup_rescan_progress, 0,
2409		sizeof(fs_info->qgroup_rescan_progress));
 
 
2410	fs_info->qgroup_rescan_progress.objectid = progress_objectid;
2411	init_completion(&fs_info->qgroup_rescan_completion);
2412
2413	spin_unlock(&fs_info->qgroup_lock);
2414	mutex_unlock(&fs_info->qgroup_rescan_lock);
2415
2416	memset(&fs_info->qgroup_rescan_work, 0,
2417	       sizeof(fs_info->qgroup_rescan_work));
2418	btrfs_init_work(&fs_info->qgroup_rescan_work,
2419			btrfs_qgroup_rescan_helper,
2420			btrfs_qgroup_rescan_worker, NULL, NULL);
2421
2422	if (ret) {
2423err:
2424		btrfs_info(fs_info, "qgroup_rescan_init failed with %d", ret);
2425		return ret;
2426	}
2427
2428	return 0;
2429}
2430
2431static void
2432qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
2433{
2434	struct rb_node *n;
2435	struct btrfs_qgroup *qgroup;
2436
2437	spin_lock(&fs_info->qgroup_lock);
2438	/* clear all current qgroup tracking information */
2439	for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
2440		qgroup = rb_entry(n, struct btrfs_qgroup, node);
2441		qgroup->rfer = 0;
2442		qgroup->rfer_cmpr = 0;
2443		qgroup->excl = 0;
2444		qgroup->excl_cmpr = 0;
 
2445	}
2446	spin_unlock(&fs_info->qgroup_lock);
2447}
2448
2449int
2450btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
2451{
2452	int ret = 0;
2453	struct btrfs_trans_handle *trans;
2454
2455	ret = qgroup_rescan_init(fs_info, 0, 1);
2456	if (ret)
2457		return ret;
2458
2459	/*
2460	 * We have set the rescan_progress to 0, which means no more
2461	 * delayed refs will be accounted by btrfs_qgroup_account_ref.
2462	 * However, btrfs_qgroup_account_ref may be right after its call
2463	 * to btrfs_find_all_roots, in which case it would still do the
2464	 * accounting.
2465	 * To solve this, we're committing the transaction, which will
2466	 * ensure we run all delayed refs and only after that, we are
2467	 * going to clear all tracking information for a clean start.
2468	 */
2469
2470	trans = btrfs_join_transaction(fs_info->fs_root);
2471	if (IS_ERR(trans)) {
2472		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2473		return PTR_ERR(trans);
2474	}
2475	ret = btrfs_commit_transaction(trans, fs_info->fs_root);
2476	if (ret) {
2477		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2478		return ret;
 
2479	}
2480
2481	qgroup_rescan_zero_tracking(fs_info);
2482
 
 
2483	btrfs_queue_work(fs_info->qgroup_rescan_workers,
2484			 &fs_info->qgroup_rescan_work);
 
2485
2486	return 0;
2487}
2488
2489int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info)
 
2490{
2491	int running;
2492	int ret = 0;
2493
2494	mutex_lock(&fs_info->qgroup_rescan_lock);
2495	spin_lock(&fs_info->qgroup_lock);
2496	running = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2497	spin_unlock(&fs_info->qgroup_lock);
2498	mutex_unlock(&fs_info->qgroup_rescan_lock);
2499
2500	if (running)
 
 
 
2501		ret = wait_for_completion_interruptible(
2502					&fs_info->qgroup_rescan_completion);
 
 
2503
2504	return ret;
2505}
2506
2507/*
2508 * this is only called from open_ctree where we're still single threaded, thus
2509 * locking is omitted here.
2510 */
2511void
2512btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
2513{
2514	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
 
 
2515		btrfs_queue_work(fs_info->qgroup_rescan_workers,
2516				 &fs_info->qgroup_rescan_work);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2517}
2518
2519/*
2520 * Reserve qgroup space for range [start, start + len).
2521 *
2522 * This function will either reserve space from related qgroups or doing
2523 * nothing if the range is already reserved.
 
 
 
2524 *
2525 * Return 0 for successful reserve
2526 * Return <0 for error (including -EQUOT)
 
 
2527 *
2528 * NOTE: this function may sleep for memory allocation.
 
 
 
2529 */
2530int btrfs_qgroup_reserve_data(struct inode *inode, u64 start, u64 len)
2531{
2532	struct btrfs_root *root = BTRFS_I(inode)->root;
2533	struct extent_changeset changeset;
2534	struct ulist_node *unode;
2535	struct ulist_iterator uiter;
2536	int ret;
2537
2538	if (!root->fs_info->quota_enabled || !is_fstree(root->objectid) ||
2539	    len == 0)
 
 
 
 
 
 
 
 
 
 
2540		return 0;
 
2541
2542	changeset.bytes_changed = 0;
2543	changeset.range_changed = ulist_alloc(GFP_NOFS);
2544	ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
2545			start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS,
2546			&changeset);
2547	trace_btrfs_qgroup_reserve_data(inode, start, len,
2548					changeset.bytes_changed,
2549					QGROUP_RESERVE);
2550	if (ret < 0)
2551		goto cleanup;
2552	ret = qgroup_reserve(root, changeset.bytes_changed);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2553	if (ret < 0)
2554		goto cleanup;
2555
2556	ulist_free(changeset.range_changed);
2557	return ret;
2558
2559cleanup:
2560	/* cleanup already reserved ranges */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2561	ULIST_ITER_INIT(&uiter);
2562	while ((unode = ulist_next(changeset.range_changed, &uiter)))
2563		clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val,
2564				 unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL,
2565				 GFP_NOFS);
2566	ulist_free(changeset.range_changed);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2567	return ret;
2568}
2569
2570static int __btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len,
2571				       int free)
 
2572{
2573	struct extent_changeset changeset;
2574	int trace_op = QGROUP_RELEASE;
2575	int ret;
2576
2577	changeset.bytes_changed = 0;
2578	changeset.range_changed = ulist_alloc(GFP_NOFS);
2579	if (!changeset.range_changed)
2580		return -ENOMEM;
 
 
2581
2582	ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, start, 
2583			start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS,
2584			&changeset);
 
 
 
 
2585	if (ret < 0)
2586		goto out;
2587
2588	if (free) {
2589		qgroup_free(BTRFS_I(inode)->root, changeset.bytes_changed);
2590		trace_op = QGROUP_FREE;
2591	}
2592	trace_btrfs_qgroup_release_data(inode, start, len,
2593					changeset.bytes_changed, trace_op);
 
 
 
 
 
 
2594out:
2595	ulist_free(changeset.range_changed);
2596	return ret;
2597}
2598
2599/*
2600 * Free a reserved space range from io_tree and related qgroups
2601 *
2602 * Should be called when a range of pages get invalidated before reaching disk.
2603 * Or for error cleanup case.
 
 
2604 *
2605 * For data written to disk, use btrfs_qgroup_release_data().
2606 *
2607 * NOTE: This function may sleep for memory allocation.
2608 */
2609int btrfs_qgroup_free_data(struct inode *inode, u64 start, u64 len)
 
 
2610{
2611	return __btrfs_qgroup_release_data(inode, start, len, 1);
2612}
2613
2614/*
2615 * Release a reserved space range from io_tree only.
2616 *
2617 * Should be called when a range of pages get written to disk and corresponding
2618 * FILE_EXTENT is inserted into corresponding root.
2619 *
2620 * Since new qgroup accounting framework will only update qgroup numbers at
2621 * commit_transaction() time, its reserved space shouldn't be freed from
2622 * related qgroups.
2623 *
2624 * But we should release the range from io_tree, to allow further write to be
2625 * COWed.
2626 *
2627 * NOTE: This function may sleep for memory allocation.
2628 */
2629int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
 
 
 
 
 
 
2630{
2631	return __btrfs_qgroup_release_data(inode, start, len, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2632}
2633
2634int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes)
 
2635{
 
2636	int ret;
2637
2638	if (!root->fs_info->quota_enabled || !is_fstree(root->objectid) ||
2639	    num_bytes == 0)
2640		return 0;
2641
2642	BUG_ON(num_bytes != round_down(num_bytes, root->nodesize));
2643	ret = qgroup_reserve(root, num_bytes);
 
2644	if (ret < 0)
2645		return ret;
2646	atomic_add(num_bytes, &root->qgroup_meta_rsv);
 
 
 
 
 
 
 
 
2647	return ret;
2648}
2649
2650void btrfs_qgroup_free_meta_all(struct btrfs_root *root)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2651{
2652	int reserved;
2653
2654	if (!root->fs_info->quota_enabled || !is_fstree(root->objectid))
 
2655		return;
2656
2657	reserved = atomic_xchg(&root->qgroup_meta_rsv, 0);
2658	if (reserved == 0)
 
 
 
 
 
 
 
 
 
 
 
 
2659		return;
2660	qgroup_free(root, reserved);
 
 
 
 
 
 
 
 
 
 
2661}
2662
2663void btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes)
 
2664{
2665	if (!root->fs_info->quota_enabled || !is_fstree(root->objectid))
 
 
 
 
 
2666		return;
2667
2668	BUG_ON(num_bytes != round_down(num_bytes, root->nodesize));
2669	WARN_ON(atomic_read(&root->qgroup_meta_rsv) < num_bytes);
2670	atomic_sub(num_bytes, &root->qgroup_meta_rsv);
2671	qgroup_free(root, num_bytes);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2672}
2673
2674/*
2675 * Check qgroup reserved space leaking, normally at destory inode
2676 * time
2677 */
2678void btrfs_qgroup_check_reserved_leak(struct inode *inode)
2679{
2680	struct extent_changeset changeset;
2681	struct ulist_node *unode;
2682	struct ulist_iterator iter;
2683	int ret;
2684
2685	changeset.bytes_changed = 0;
2686	changeset.range_changed = ulist_alloc(GFP_NOFS);
2687	if (WARN_ON(!changeset.range_changed))
2688		return;
2689
2690	ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
2691			EXTENT_QGROUP_RESERVED, GFP_NOFS, &changeset);
2692
2693	WARN_ON(ret < 0);
2694	if (WARN_ON(changeset.bytes_changed)) {
2695		ULIST_ITER_INIT(&iter);
2696		while ((unode = ulist_next(changeset.range_changed, &iter))) {
2697			btrfs_warn(BTRFS_I(inode)->root->fs_info,
2698				"leaking qgroup reserved space, ino: %lu, start: %llu, end: %llu",
2699				inode->i_ino, unode->val, unode->aux);
2700		}
2701		qgroup_free(BTRFS_I(inode)->root, changeset.bytes_changed);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2702	}
2703	ulist_free(changeset.range_changed);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2704}
v6.9.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2011 STRATO.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   4 */
   5
   6#include <linux/sched.h>
   7#include <linux/pagemap.h>
   8#include <linux/writeback.h>
   9#include <linux/blkdev.h>
  10#include <linux/rbtree.h>
  11#include <linux/slab.h>
  12#include <linux/workqueue.h>
  13#include <linux/btrfs.h>
  14#include <linux/sched/mm.h>
  15
  16#include "ctree.h"
  17#include "transaction.h"
  18#include "disk-io.h"
  19#include "locking.h"
  20#include "ulist.h"
  21#include "backref.h"
  22#include "extent_io.h"
  23#include "qgroup.h"
  24#include "block-group.h"
  25#include "sysfs.h"
  26#include "tree-mod-log.h"
  27#include "fs.h"
  28#include "accessors.h"
  29#include "extent-tree.h"
  30#include "root-tree.h"
  31#include "tree-checker.h"
  32
  33enum btrfs_qgroup_mode btrfs_qgroup_mode(struct btrfs_fs_info *fs_info)
  34{
  35	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
  36		return BTRFS_QGROUP_MODE_DISABLED;
  37	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE)
  38		return BTRFS_QGROUP_MODE_SIMPLE;
  39	return BTRFS_QGROUP_MODE_FULL;
  40}
  41
  42bool btrfs_qgroup_enabled(struct btrfs_fs_info *fs_info)
  43{
  44	return btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_DISABLED;
  45}
  46
  47bool btrfs_qgroup_full_accounting(struct btrfs_fs_info *fs_info)
  48{
  49	return btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL;
  50}
 
 
  51
  52/*
  53 * Helpers to access qgroup reservation
  54 *
  55 * Callers should ensure the lock context and type are valid
  56 */
 
 
  57
  58static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup)
  59{
  60	u64 ret = 0;
  61	int i;
 
 
 
  62
  63	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
  64		ret += qgroup->rsv.values[i];
 
 
 
 
 
 
  65
  66	return ret;
  67}
 
 
  68
  69#ifdef CONFIG_BTRFS_DEBUG
  70static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type)
  71{
  72	if (type == BTRFS_QGROUP_RSV_DATA)
  73		return "data";
  74	if (type == BTRFS_QGROUP_RSV_META_PERTRANS)
  75		return "meta_pertrans";
  76	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
  77		return "meta_prealloc";
  78	return NULL;
  79}
  80#endif
  81
  82static void qgroup_rsv_add(struct btrfs_fs_info *fs_info,
  83			   struct btrfs_qgroup *qgroup, u64 num_bytes,
  84			   enum btrfs_qgroup_rsv_type type)
  85{
  86	trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type);
  87	qgroup->rsv.values[type] += num_bytes;
  88}
  89
  90static void qgroup_rsv_release(struct btrfs_fs_info *fs_info,
  91			       struct btrfs_qgroup *qgroup, u64 num_bytes,
  92			       enum btrfs_qgroup_rsv_type type)
  93{
  94	trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type);
  95	if (qgroup->rsv.values[type] >= num_bytes) {
  96		qgroup->rsv.values[type] -= num_bytes;
  97		return;
  98	}
  99#ifdef CONFIG_BTRFS_DEBUG
 100	WARN_RATELIMIT(1,
 101		"qgroup %llu %s reserved space underflow, have %llu to free %llu",
 102		qgroup->qgroupid, qgroup_rsv_type_str(type),
 103		qgroup->rsv.values[type], num_bytes);
 104#endif
 105	qgroup->rsv.values[type] = 0;
 106}
 107
 108static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info,
 109				     struct btrfs_qgroup *dest,
 110				     struct btrfs_qgroup *src)
 111{
 112	int i;
 113
 114	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 115		qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i);
 116}
 117
 118static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info,
 119					 struct btrfs_qgroup *dest,
 120					  struct btrfs_qgroup *src)
 121{
 122	int i;
 123
 124	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 125		qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i);
 126}
 127
 128static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
 129					   int mod)
 130{
 131	if (qg->old_refcnt < seq)
 132		qg->old_refcnt = seq;
 133	qg->old_refcnt += mod;
 134}
 135
 136static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
 137					   int mod)
 138{
 139	if (qg->new_refcnt < seq)
 140		qg->new_refcnt = seq;
 141	qg->new_refcnt += mod;
 142}
 143
 144static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
 145{
 146	if (qg->old_refcnt < seq)
 147		return 0;
 148	return qg->old_refcnt - seq;
 149}
 150
 151static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
 152{
 153	if (qg->new_refcnt < seq)
 154		return 0;
 155	return qg->new_refcnt - seq;
 156}
 157
 158/*
 159 * glue structure to represent the relations between qgroups.
 160 */
 161struct btrfs_qgroup_list {
 162	struct list_head next_group;
 163	struct list_head next_member;
 164	struct btrfs_qgroup *group;
 165	struct btrfs_qgroup *member;
 166};
 167
 
 
 
 168static int
 169qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
 170		   int init_flags);
 171static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 172
 173/* must be called with qgroup_ioctl_lock held */
 174static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
 175					   u64 qgroupid)
 176{
 177	struct rb_node *n = fs_info->qgroup_tree.rb_node;
 178	struct btrfs_qgroup *qgroup;
 179
 180	while (n) {
 181		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 182		if (qgroup->qgroupid < qgroupid)
 183			n = n->rb_left;
 184		else if (qgroup->qgroupid > qgroupid)
 185			n = n->rb_right;
 186		else
 187			return qgroup;
 188	}
 189	return NULL;
 190}
 191
 192/*
 193 * Add qgroup to the filesystem's qgroup tree.
 194 *
 195 * Must be called with qgroup_lock held and @prealloc preallocated.
 196 *
 197 * The control on the lifespan of @prealloc would be transferred to this
 198 * function, thus caller should no longer touch @prealloc.
 199 */
 200static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
 201					  struct btrfs_qgroup *prealloc,
 202					  u64 qgroupid)
 203{
 204	struct rb_node **p = &fs_info->qgroup_tree.rb_node;
 205	struct rb_node *parent = NULL;
 206	struct btrfs_qgroup *qgroup;
 207
 208	/* Caller must have pre-allocated @prealloc. */
 209	ASSERT(prealloc);
 210
 211	while (*p) {
 212		parent = *p;
 213		qgroup = rb_entry(parent, struct btrfs_qgroup, node);
 214
 215		if (qgroup->qgroupid < qgroupid) {
 216			p = &(*p)->rb_left;
 217		} else if (qgroup->qgroupid > qgroupid) {
 218			p = &(*p)->rb_right;
 219		} else {
 220			kfree(prealloc);
 221			return qgroup;
 222		}
 223	}
 224
 225	qgroup = prealloc;
 
 
 
 226	qgroup->qgroupid = qgroupid;
 227	INIT_LIST_HEAD(&qgroup->groups);
 228	INIT_LIST_HEAD(&qgroup->members);
 229	INIT_LIST_HEAD(&qgroup->dirty);
 230	INIT_LIST_HEAD(&qgroup->iterator);
 231	INIT_LIST_HEAD(&qgroup->nested_iterator);
 232
 233	rb_link_node(&qgroup->node, parent, p);
 234	rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
 235
 236	return qgroup;
 237}
 238
 239static void __del_qgroup_rb(struct btrfs_fs_info *fs_info,
 240			    struct btrfs_qgroup *qgroup)
 241{
 242	struct btrfs_qgroup_list *list;
 243
 244	list_del(&qgroup->dirty);
 245	while (!list_empty(&qgroup->groups)) {
 246		list = list_first_entry(&qgroup->groups,
 247					struct btrfs_qgroup_list, next_group);
 248		list_del(&list->next_group);
 249		list_del(&list->next_member);
 250		kfree(list);
 251	}
 252
 253	while (!list_empty(&qgroup->members)) {
 254		list = list_first_entry(&qgroup->members,
 255					struct btrfs_qgroup_list, next_member);
 256		list_del(&list->next_group);
 257		list_del(&list->next_member);
 258		kfree(list);
 259	}
 
 260}
 261
 262/* must be called with qgroup_lock held */
 263static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
 264{
 265	struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
 266
 267	if (!qgroup)
 268		return -ENOENT;
 269
 270	rb_erase(&qgroup->node, &fs_info->qgroup_tree);
 271	__del_qgroup_rb(fs_info, qgroup);
 272	return 0;
 273}
 274
 275/*
 276 * Add relation specified by two qgroups.
 277 *
 278 * Must be called with qgroup_lock held, the ownership of @prealloc is
 279 * transferred to this function and caller should not touch it anymore.
 280 *
 281 * Return: 0        on success
 282 *         -ENOENT  if one of the qgroups is NULL
 283 *         <0       other errors
 284 */
 285static int __add_relation_rb(struct btrfs_qgroup_list *prealloc,
 286			     struct btrfs_qgroup *member,
 287			     struct btrfs_qgroup *parent)
 288{
 289	if (!member || !parent) {
 290		kfree(prealloc);
 291		return -ENOENT;
 292	}
 293
 294	prealloc->group = parent;
 295	prealloc->member = member;
 296	list_add_tail(&prealloc->next_group, &member->groups);
 297	list_add_tail(&prealloc->next_member, &parent->members);
 298
 299	return 0;
 300}
 301
 302/*
 303 * Add relation specified by two qgroup ids.
 304 *
 305 * Must be called with qgroup_lock held.
 306 *
 307 * Return: 0        on success
 308 *         -ENOENT  if one of the ids does not exist
 309 *         <0       other errors
 310 */
 311static int add_relation_rb(struct btrfs_fs_info *fs_info,
 312			   struct btrfs_qgroup_list *prealloc,
 313			   u64 memberid, u64 parentid)
 314{
 315	struct btrfs_qgroup *member;
 316	struct btrfs_qgroup *parent;
 
 317
 318	member = find_qgroup_rb(fs_info, memberid);
 319	parent = find_qgroup_rb(fs_info, parentid);
 
 
 
 
 
 
 320
 321	return __add_relation_rb(prealloc, member, parent);
 
 
 
 
 
 322}
 323
 324/* Must be called with qgroup_lock held */
 325static int del_relation_rb(struct btrfs_fs_info *fs_info,
 326			   u64 memberid, u64 parentid)
 327{
 328	struct btrfs_qgroup *member;
 329	struct btrfs_qgroup *parent;
 330	struct btrfs_qgroup_list *list;
 331
 332	member = find_qgroup_rb(fs_info, memberid);
 333	parent = find_qgroup_rb(fs_info, parentid);
 334	if (!member || !parent)
 335		return -ENOENT;
 336
 337	list_for_each_entry(list, &member->groups, next_group) {
 338		if (list->group == parent) {
 339			list_del(&list->next_group);
 340			list_del(&list->next_member);
 341			kfree(list);
 342			return 0;
 343		}
 344	}
 345	return -ENOENT;
 346}
 347
 348#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 349int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
 350			       u64 rfer, u64 excl)
 351{
 352	struct btrfs_qgroup *qgroup;
 353
 354	qgroup = find_qgroup_rb(fs_info, qgroupid);
 355	if (!qgroup)
 356		return -EINVAL;
 357	if (qgroup->rfer != rfer || qgroup->excl != excl)
 358		return -EINVAL;
 359	return 0;
 360}
 361#endif
 362
 363static void qgroup_mark_inconsistent(struct btrfs_fs_info *fs_info)
 364{
 365	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
 366		return;
 367	fs_info->qgroup_flags |= (BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT |
 368				  BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
 369				  BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
 370}
 371
 372static void qgroup_read_enable_gen(struct btrfs_fs_info *fs_info,
 373				   struct extent_buffer *leaf, int slot,
 374				   struct btrfs_qgroup_status_item *ptr)
 375{
 376	ASSERT(btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
 377	ASSERT(btrfs_item_size(leaf, slot) >= sizeof(*ptr));
 378	fs_info->qgroup_enable_gen = btrfs_qgroup_status_enable_gen(leaf, ptr);
 379}
 380
 381/*
 382 * The full config is read in one go, only called from open_ctree()
 383 * It doesn't use any locking, as at this point we're still single-threaded
 384 */
 385int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
 386{
 387	struct btrfs_key key;
 388	struct btrfs_key found_key;
 389	struct btrfs_root *quota_root = fs_info->quota_root;
 390	struct btrfs_path *path = NULL;
 391	struct extent_buffer *l;
 392	int slot;
 393	int ret = 0;
 394	u64 flags = 0;
 395	u64 rescan_progress = 0;
 396
 397	if (!fs_info->quota_root)
 398		return 0;
 399
 400	fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 401	if (!fs_info->qgroup_ulist) {
 402		ret = -ENOMEM;
 403		goto out;
 404	}
 405
 406	path = btrfs_alloc_path();
 407	if (!path) {
 408		ret = -ENOMEM;
 409		goto out;
 410	}
 411
 412	ret = btrfs_sysfs_add_qgroups(fs_info);
 413	if (ret < 0)
 414		goto out;
 415	/* default this to quota off, in case no status key is found */
 416	fs_info->qgroup_flags = 0;
 417
 418	/*
 419	 * pass 1: read status, all qgroup infos and limits
 420	 */
 421	key.objectid = 0;
 422	key.type = 0;
 423	key.offset = 0;
 424	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
 425	if (ret)
 426		goto out;
 427
 428	while (1) {
 429		struct btrfs_qgroup *qgroup;
 430
 431		slot = path->slots[0];
 432		l = path->nodes[0];
 433		btrfs_item_key_to_cpu(l, &found_key, slot);
 434
 435		if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
 436			struct btrfs_qgroup_status_item *ptr;
 437
 438			ptr = btrfs_item_ptr(l, slot,
 439					     struct btrfs_qgroup_status_item);
 440
 441			if (btrfs_qgroup_status_version(l, ptr) !=
 442			    BTRFS_QGROUP_STATUS_VERSION) {
 443				btrfs_err(fs_info,
 444				 "old qgroup version, quota disabled");
 445				goto out;
 446			}
 447			fs_info->qgroup_flags = btrfs_qgroup_status_flags(l, ptr);
 448			if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE) {
 449				qgroup_read_enable_gen(fs_info, l, slot, ptr);
 450			} else if (btrfs_qgroup_status_generation(l, ptr) != fs_info->generation) {
 451				qgroup_mark_inconsistent(fs_info);
 452				btrfs_err(fs_info,
 453					"qgroup generation mismatch, marked as inconsistent");
 
 454			}
 
 
 455			rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
 456			goto next1;
 457		}
 458
 459		if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
 460		    found_key.type != BTRFS_QGROUP_LIMIT_KEY)
 461			goto next1;
 462
 463		qgroup = find_qgroup_rb(fs_info, found_key.offset);
 464		if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
 465		    (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
 466			btrfs_err(fs_info, "inconsistent qgroup config");
 467			qgroup_mark_inconsistent(fs_info);
 468		}
 469		if (!qgroup) {
 470			struct btrfs_qgroup *prealloc;
 471
 472			prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL);
 473			if (!prealloc) {
 474				ret = -ENOMEM;
 475				goto out;
 476			}
 477			qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset);
 478		}
 479		ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
 480		if (ret < 0)
 481			goto out;
 482
 483		switch (found_key.type) {
 484		case BTRFS_QGROUP_INFO_KEY: {
 485			struct btrfs_qgroup_info_item *ptr;
 486
 487			ptr = btrfs_item_ptr(l, slot,
 488					     struct btrfs_qgroup_info_item);
 489			qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
 490			qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
 491			qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
 492			qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
 493			/* generation currently unused */
 494			break;
 495		}
 496		case BTRFS_QGROUP_LIMIT_KEY: {
 497			struct btrfs_qgroup_limit_item *ptr;
 498
 499			ptr = btrfs_item_ptr(l, slot,
 500					     struct btrfs_qgroup_limit_item);
 501			qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
 502			qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
 503			qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
 504			qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
 505			qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
 506			break;
 507		}
 508		}
 509next1:
 510		ret = btrfs_next_item(quota_root, path);
 511		if (ret < 0)
 512			goto out;
 513		if (ret)
 514			break;
 515	}
 516	btrfs_release_path(path);
 517
 518	/*
 519	 * pass 2: read all qgroup relations
 520	 */
 521	key.objectid = 0;
 522	key.type = BTRFS_QGROUP_RELATION_KEY;
 523	key.offset = 0;
 524	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
 525	if (ret)
 526		goto out;
 527	while (1) {
 528		struct btrfs_qgroup_list *list = NULL;
 529
 530		slot = path->slots[0];
 531		l = path->nodes[0];
 532		btrfs_item_key_to_cpu(l, &found_key, slot);
 533
 534		if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
 535			goto next2;
 536
 537		if (found_key.objectid > found_key.offset) {
 538			/* parent <- member, not needed to build config */
 539			/* FIXME should we omit the key completely? */
 540			goto next2;
 541		}
 542
 543		list = kzalloc(sizeof(*list), GFP_KERNEL);
 544		if (!list) {
 545			ret = -ENOMEM;
 546			goto out;
 547		}
 548		ret = add_relation_rb(fs_info, list, found_key.objectid,
 549				      found_key.offset);
 550		list = NULL;
 551		if (ret == -ENOENT) {
 552			btrfs_warn(fs_info,
 553				"orphan qgroup relation 0x%llx->0x%llx",
 554				found_key.objectid, found_key.offset);
 555			ret = 0;	/* ignore the error */
 556		}
 557		if (ret)
 558			goto out;
 559next2:
 560		ret = btrfs_next_item(quota_root, path);
 561		if (ret < 0)
 562			goto out;
 563		if (ret)
 564			break;
 565	}
 566out:
 
 
 
 
 
 
 
 
 567	btrfs_free_path(path);
 568	fs_info->qgroup_flags |= flags;
 569	if (ret >= 0) {
 570		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)
 571			set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
 572		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
 573			ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
 574	} else {
 575		ulist_free(fs_info->qgroup_ulist);
 576		fs_info->qgroup_ulist = NULL;
 577		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
 578		btrfs_sysfs_del_qgroups(fs_info);
 579	}
 580
 581	return ret < 0 ? ret : 0;
 582}
 583
 584/*
 585 * Called in close_ctree() when quota is still enabled.  This verifies we don't
 586 * leak some reserved space.
 587 *
 588 * Return false if no reserved space is left.
 589 * Return true if some reserved space is leaked.
 590 */
 591bool btrfs_check_quota_leak(struct btrfs_fs_info *fs_info)
 592{
 593	struct rb_node *node;
 594	bool ret = false;
 595
 596	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
 597		return ret;
 598	/*
 599	 * Since we're unmounting, there is no race and no need to grab qgroup
 600	 * lock.  And here we don't go post-order to provide a more user
 601	 * friendly sorted result.
 602	 */
 603	for (node = rb_first(&fs_info->qgroup_tree); node; node = rb_next(node)) {
 604		struct btrfs_qgroup *qgroup;
 605		int i;
 606
 607		qgroup = rb_entry(node, struct btrfs_qgroup, node);
 608		for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) {
 609			if (qgroup->rsv.values[i]) {
 610				ret = true;
 611				btrfs_warn(fs_info,
 612		"qgroup %hu/%llu has unreleased space, type %d rsv %llu",
 613				   btrfs_qgroup_level(qgroup->qgroupid),
 614				   btrfs_qgroup_subvolid(qgroup->qgroupid),
 615				   i, qgroup->rsv.values[i]);
 616			}
 617		}
 618	}
 619	return ret;
 620}
 621
 622/*
 623 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
 624 * first two are in single-threaded paths.And for the third one, we have set
 625 * quota_root to be null with qgroup_lock held before, so it is safe to clean
 626 * up the in-memory structures without qgroup_lock held.
 627 */
 628void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
 629{
 630	struct rb_node *n;
 631	struct btrfs_qgroup *qgroup;
 632
 633	while ((n = rb_first(&fs_info->qgroup_tree))) {
 634		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 635		rb_erase(n, &fs_info->qgroup_tree);
 636		__del_qgroup_rb(fs_info, qgroup);
 637		btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
 638		kfree(qgroup);
 639	}
 640	/*
 641	 * We call btrfs_free_qgroup_config() when unmounting
 642	 * filesystem and disabling quota, so we set qgroup_ulist
 643	 * to be null here to avoid double free.
 644	 */
 645	ulist_free(fs_info->qgroup_ulist);
 646	fs_info->qgroup_ulist = NULL;
 647	btrfs_sysfs_del_qgroups(fs_info);
 648}
 649
 650static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 651				    u64 dst)
 
 652{
 653	int ret;
 654	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 655	struct btrfs_path *path;
 656	struct btrfs_key key;
 657
 658	path = btrfs_alloc_path();
 659	if (!path)
 660		return -ENOMEM;
 661
 662	key.objectid = src;
 663	key.type = BTRFS_QGROUP_RELATION_KEY;
 664	key.offset = dst;
 665
 666	ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
 667
 668	btrfs_mark_buffer_dirty(trans, path->nodes[0]);
 669
 670	btrfs_free_path(path);
 671	return ret;
 672}
 673
 674static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 675				    u64 dst)
 
 676{
 677	int ret;
 678	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 679	struct btrfs_path *path;
 680	struct btrfs_key key;
 681
 682	path = btrfs_alloc_path();
 683	if (!path)
 684		return -ENOMEM;
 685
 686	key.objectid = src;
 687	key.type = BTRFS_QGROUP_RELATION_KEY;
 688	key.offset = dst;
 689
 690	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 691	if (ret < 0)
 692		goto out;
 693
 694	if (ret > 0) {
 695		ret = -ENOENT;
 696		goto out;
 697	}
 698
 699	ret = btrfs_del_item(trans, quota_root, path);
 700out:
 701	btrfs_free_path(path);
 702	return ret;
 703}
 704
 705static int add_qgroup_item(struct btrfs_trans_handle *trans,
 706			   struct btrfs_root *quota_root, u64 qgroupid)
 707{
 708	int ret;
 709	struct btrfs_path *path;
 710	struct btrfs_qgroup_info_item *qgroup_info;
 711	struct btrfs_qgroup_limit_item *qgroup_limit;
 712	struct extent_buffer *leaf;
 713	struct btrfs_key key;
 714
 715	if (btrfs_is_testing(quota_root->fs_info))
 716		return 0;
 717
 718	path = btrfs_alloc_path();
 719	if (!path)
 720		return -ENOMEM;
 721
 722	key.objectid = 0;
 723	key.type = BTRFS_QGROUP_INFO_KEY;
 724	key.offset = qgroupid;
 725
 726	/*
 727	 * Avoid a transaction abort by catching -EEXIST here. In that
 728	 * case, we proceed by re-initializing the existing structure
 729	 * on disk.
 730	 */
 731
 732	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 733				      sizeof(*qgroup_info));
 734	if (ret && ret != -EEXIST)
 735		goto out;
 736
 737	leaf = path->nodes[0];
 738	qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
 739				 struct btrfs_qgroup_info_item);
 740	btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
 741	btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
 742	btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
 743	btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
 744	btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
 745
 746	btrfs_mark_buffer_dirty(trans, leaf);
 747
 748	btrfs_release_path(path);
 749
 750	key.type = BTRFS_QGROUP_LIMIT_KEY;
 751	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 752				      sizeof(*qgroup_limit));
 753	if (ret && ret != -EEXIST)
 754		goto out;
 755
 756	leaf = path->nodes[0];
 757	qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
 758				  struct btrfs_qgroup_limit_item);
 759	btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
 760	btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
 761	btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
 762	btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
 763	btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
 764
 765	btrfs_mark_buffer_dirty(trans, leaf);
 766
 767	ret = 0;
 768out:
 769	btrfs_free_path(path);
 770	return ret;
 771}
 772
 773static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid)
 
 774{
 775	int ret;
 776	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 777	struct btrfs_path *path;
 778	struct btrfs_key key;
 779
 780	path = btrfs_alloc_path();
 781	if (!path)
 782		return -ENOMEM;
 783
 784	key.objectid = 0;
 785	key.type = BTRFS_QGROUP_INFO_KEY;
 786	key.offset = qgroupid;
 787	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 788	if (ret < 0)
 789		goto out;
 790
 791	if (ret > 0) {
 792		ret = -ENOENT;
 793		goto out;
 794	}
 795
 796	ret = btrfs_del_item(trans, quota_root, path);
 797	if (ret)
 798		goto out;
 799
 800	btrfs_release_path(path);
 801
 802	key.type = BTRFS_QGROUP_LIMIT_KEY;
 803	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 804	if (ret < 0)
 805		goto out;
 806
 807	if (ret > 0) {
 808		ret = -ENOENT;
 809		goto out;
 810	}
 811
 812	ret = btrfs_del_item(trans, quota_root, path);
 813
 814out:
 815	btrfs_free_path(path);
 816	return ret;
 817}
 818
 819static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
 
 820				    struct btrfs_qgroup *qgroup)
 821{
 822	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 823	struct btrfs_path *path;
 824	struct btrfs_key key;
 825	struct extent_buffer *l;
 826	struct btrfs_qgroup_limit_item *qgroup_limit;
 827	int ret;
 828	int slot;
 829
 830	key.objectid = 0;
 831	key.type = BTRFS_QGROUP_LIMIT_KEY;
 832	key.offset = qgroup->qgroupid;
 833
 834	path = btrfs_alloc_path();
 835	if (!path)
 836		return -ENOMEM;
 837
 838	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 839	if (ret > 0)
 840		ret = -ENOENT;
 841
 842	if (ret)
 843		goto out;
 844
 845	l = path->nodes[0];
 846	slot = path->slots[0];
 847	qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
 848	btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
 849	btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
 850	btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
 851	btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
 852	btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
 853
 854	btrfs_mark_buffer_dirty(trans, l);
 855
 856out:
 857	btrfs_free_path(path);
 858	return ret;
 859}
 860
 861static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
 
 862				   struct btrfs_qgroup *qgroup)
 863{
 864	struct btrfs_fs_info *fs_info = trans->fs_info;
 865	struct btrfs_root *quota_root = fs_info->quota_root;
 866	struct btrfs_path *path;
 867	struct btrfs_key key;
 868	struct extent_buffer *l;
 869	struct btrfs_qgroup_info_item *qgroup_info;
 870	int ret;
 871	int slot;
 872
 873	if (btrfs_is_testing(fs_info))
 874		return 0;
 875
 876	key.objectid = 0;
 877	key.type = BTRFS_QGROUP_INFO_KEY;
 878	key.offset = qgroup->qgroupid;
 879
 880	path = btrfs_alloc_path();
 881	if (!path)
 882		return -ENOMEM;
 883
 884	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 885	if (ret > 0)
 886		ret = -ENOENT;
 887
 888	if (ret)
 889		goto out;
 890
 891	l = path->nodes[0];
 892	slot = path->slots[0];
 893	qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 894	btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 895	btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 896	btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 897	btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 898	btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 899
 900	btrfs_mark_buffer_dirty(trans, l);
 901
 902out:
 903	btrfs_free_path(path);
 904	return ret;
 905}
 906
 907static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
 
 
 908{
 909	struct btrfs_fs_info *fs_info = trans->fs_info;
 910	struct btrfs_root *quota_root = fs_info->quota_root;
 911	struct btrfs_path *path;
 912	struct btrfs_key key;
 913	struct extent_buffer *l;
 914	struct btrfs_qgroup_status_item *ptr;
 915	int ret;
 916	int slot;
 917
 918	key.objectid = 0;
 919	key.type = BTRFS_QGROUP_STATUS_KEY;
 920	key.offset = 0;
 921
 922	path = btrfs_alloc_path();
 923	if (!path)
 924		return -ENOMEM;
 925
 926	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 927	if (ret > 0)
 928		ret = -ENOENT;
 929
 930	if (ret)
 931		goto out;
 932
 933	l = path->nodes[0];
 934	slot = path->slots[0];
 935	ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 936	btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags &
 937				      BTRFS_QGROUP_STATUS_FLAGS_MASK);
 938	btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 939	btrfs_set_qgroup_status_rescan(l, ptr,
 940				fs_info->qgroup_rescan_progress.objectid);
 941
 942	btrfs_mark_buffer_dirty(trans, l);
 943
 944out:
 945	btrfs_free_path(path);
 946	return ret;
 947}
 948
 949/*
 950 * called with qgroup_lock held
 951 */
 952static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 953				  struct btrfs_root *root)
 954{
 955	struct btrfs_path *path;
 956	struct btrfs_key key;
 957	struct extent_buffer *leaf = NULL;
 958	int ret;
 959	int nr = 0;
 960
 961	path = btrfs_alloc_path();
 962	if (!path)
 963		return -ENOMEM;
 964
 
 
 965	key.objectid = 0;
 966	key.offset = 0;
 967	key.type = 0;
 968
 969	while (1) {
 970		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 971		if (ret < 0)
 972			goto out;
 973		leaf = path->nodes[0];
 974		nr = btrfs_header_nritems(leaf);
 975		if (!nr)
 976			break;
 977		/*
 978		 * delete the leaf one by one
 979		 * since the whole tree is going
 980		 * to be deleted.
 981		 */
 982		path->slots[0] = 0;
 983		ret = btrfs_del_items(trans, root, path, 0, nr);
 984		if (ret)
 985			goto out;
 986
 987		btrfs_release_path(path);
 988	}
 989	ret = 0;
 990out:
 
 991	btrfs_free_path(path);
 992	return ret;
 993}
 994
 995int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
 996		       struct btrfs_ioctl_quota_ctl_args *quota_ctl_args)
 997{
 998	struct btrfs_root *quota_root;
 999	struct btrfs_root *tree_root = fs_info->tree_root;
1000	struct btrfs_path *path = NULL;
1001	struct btrfs_qgroup_status_item *ptr;
1002	struct extent_buffer *leaf;
1003	struct btrfs_key key;
1004	struct btrfs_key found_key;
1005	struct btrfs_qgroup *qgroup = NULL;
1006	struct btrfs_qgroup *prealloc = NULL;
1007	struct btrfs_trans_handle *trans = NULL;
1008	struct ulist *ulist = NULL;
1009	const bool simple = (quota_ctl_args->cmd == BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA);
1010	int ret = 0;
1011	int slot;
1012
1013	/*
1014	 * We need to have subvol_sem write locked, to prevent races between
1015	 * concurrent tasks trying to enable quotas, because we will unlock
1016	 * and relock qgroup_ioctl_lock before setting fs_info->quota_root
1017	 * and before setting BTRFS_FS_QUOTA_ENABLED.
1018	 */
1019	lockdep_assert_held_write(&fs_info->subvol_sem);
1020
1021	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
1022		btrfs_err(fs_info,
1023			  "qgroups are currently unsupported in extent tree v2");
1024		return -EINVAL;
1025	}
1026
1027	mutex_lock(&fs_info->qgroup_ioctl_lock);
1028	if (fs_info->quota_root)
 
1029		goto out;
 
1030
1031	ulist = ulist_alloc(GFP_KERNEL);
1032	if (!ulist) {
1033		ret = -ENOMEM;
1034		goto out;
1035	}
1036
1037	ret = btrfs_sysfs_add_qgroups(fs_info);
1038	if (ret < 0)
1039		goto out;
1040
1041	/*
1042	 * Unlock qgroup_ioctl_lock before starting the transaction. This is to
1043	 * avoid lock acquisition inversion problems (reported by lockdep) between
1044	 * qgroup_ioctl_lock and the vfs freeze semaphores, acquired when we
1045	 * start a transaction.
1046	 * After we started the transaction lock qgroup_ioctl_lock again and
1047	 * check if someone else created the quota root in the meanwhile. If so,
1048	 * just return success and release the transaction handle.
1049	 *
1050	 * Also we don't need to worry about someone else calling
1051	 * btrfs_sysfs_add_qgroups() after we unlock and getting an error because
1052	 * that function returns 0 (success) when the sysfs entries already exist.
1053	 */
1054	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1055
1056	/*
1057	 * 1 for quota root item
1058	 * 1 for BTRFS_QGROUP_STATUS item
1059	 *
1060	 * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items
1061	 * per subvolume. However those are not currently reserved since it
1062	 * would be a lot of overkill.
1063	 */
1064	trans = btrfs_start_transaction(tree_root, 2);
1065
1066	mutex_lock(&fs_info->qgroup_ioctl_lock);
1067	if (IS_ERR(trans)) {
1068		ret = PTR_ERR(trans);
1069		trans = NULL;
1070		goto out;
1071	}
1072
1073	if (fs_info->quota_root)
1074		goto out;
1075
1076	fs_info->qgroup_ulist = ulist;
1077	ulist = NULL;
1078
1079	/*
1080	 * initially create the quota tree
1081	 */
1082	quota_root = btrfs_create_tree(trans, BTRFS_QUOTA_TREE_OBJECTID);
 
1083	if (IS_ERR(quota_root)) {
1084		ret =  PTR_ERR(quota_root);
1085		btrfs_abort_transaction(trans, ret);
1086		goto out;
1087	}
1088
1089	path = btrfs_alloc_path();
1090	if (!path) {
1091		ret = -ENOMEM;
1092		btrfs_abort_transaction(trans, ret);
1093		goto out_free_root;
1094	}
1095
1096	key.objectid = 0;
1097	key.type = BTRFS_QGROUP_STATUS_KEY;
1098	key.offset = 0;
1099
1100	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
1101				      sizeof(*ptr));
1102	if (ret) {
1103		btrfs_abort_transaction(trans, ret);
1104		goto out_free_path;
1105	}
1106
1107	leaf = path->nodes[0];
1108	ptr = btrfs_item_ptr(leaf, path->slots[0],
1109				 struct btrfs_qgroup_status_item);
1110	btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
1111	btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
1112	fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON;
1113	if (simple) {
1114		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1115		btrfs_set_qgroup_status_enable_gen(leaf, ptr, trans->transid);
1116	} else {
1117		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1118	}
1119	btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags &
1120				      BTRFS_QGROUP_STATUS_FLAGS_MASK);
1121	btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
1122
1123	btrfs_mark_buffer_dirty(trans, leaf);
1124
1125	key.objectid = 0;
1126	key.type = BTRFS_ROOT_REF_KEY;
1127	key.offset = 0;
1128
1129	btrfs_release_path(path);
1130	ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
1131	if (ret > 0)
1132		goto out_add_root;
1133	if (ret < 0) {
1134		btrfs_abort_transaction(trans, ret);
1135		goto out_free_path;
1136	}
1137
1138	while (1) {
1139		slot = path->slots[0];
1140		leaf = path->nodes[0];
1141		btrfs_item_key_to_cpu(leaf, &found_key, slot);
1142
1143		if (found_key.type == BTRFS_ROOT_REF_KEY) {
1144
1145			/* Release locks on tree_root before we access quota_root */
1146			btrfs_release_path(path);
1147
1148			/* We should not have a stray @prealloc pointer. */
1149			ASSERT(prealloc == NULL);
1150			prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1151			if (!prealloc) {
1152				ret = -ENOMEM;
1153				btrfs_abort_transaction(trans, ret);
1154				goto out_free_path;
1155			}
1156
1157			ret = add_qgroup_item(trans, quota_root,
1158					      found_key.offset);
1159			if (ret) {
1160				btrfs_abort_transaction(trans, ret);
1161				goto out_free_path;
1162			}
1163
1164			qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset);
1165			prealloc = NULL;
1166			if (IS_ERR(qgroup)) {
1167				ret = PTR_ERR(qgroup);
1168				btrfs_abort_transaction(trans, ret);
1169				goto out_free_path;
1170			}
1171			ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1172			if (ret < 0) {
1173				btrfs_abort_transaction(trans, ret);
1174				goto out_free_path;
1175			}
1176			ret = btrfs_search_slot_for_read(tree_root, &found_key,
1177							 path, 1, 0);
1178			if (ret < 0) {
1179				btrfs_abort_transaction(trans, ret);
1180				goto out_free_path;
1181			}
1182			if (ret > 0) {
1183				/*
1184				 * Shouldn't happen, but in case it does we
1185				 * don't need to do the btrfs_next_item, just
1186				 * continue.
1187				 */
1188				continue;
1189			}
1190		}
1191		ret = btrfs_next_item(tree_root, path);
1192		if (ret < 0) {
1193			btrfs_abort_transaction(trans, ret);
1194			goto out_free_path;
1195		}
1196		if (ret)
1197			break;
1198	}
1199
1200out_add_root:
1201	btrfs_release_path(path);
1202	ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
1203	if (ret) {
1204		btrfs_abort_transaction(trans, ret);
1205		goto out_free_path;
1206	}
1207
1208	ASSERT(prealloc == NULL);
1209	prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1210	if (!prealloc) {
1211		ret = -ENOMEM;
1212		goto out_free_path;
1213	}
1214	qgroup = add_qgroup_rb(fs_info, prealloc, BTRFS_FS_TREE_OBJECTID);
1215	prealloc = NULL;
1216	ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1217	if (ret < 0) {
1218		btrfs_abort_transaction(trans, ret);
1219		goto out_free_path;
1220	}
1221
1222	fs_info->qgroup_enable_gen = trans->transid;
1223
1224	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1225	/*
1226	 * Commit the transaction while not holding qgroup_ioctl_lock, to avoid
1227	 * a deadlock with tasks concurrently doing other qgroup operations, such
1228	 * adding/removing qgroups or adding/deleting qgroup relations for example,
1229	 * because all qgroup operations first start or join a transaction and then
1230	 * lock the qgroup_ioctl_lock mutex.
1231	 * We are safe from a concurrent task trying to enable quotas, by calling
1232	 * this function, since we are serialized by fs_info->subvol_sem.
1233	 */
1234	ret = btrfs_commit_transaction(trans);
1235	trans = NULL;
1236	mutex_lock(&fs_info->qgroup_ioctl_lock);
1237	if (ret)
1238		goto out_free_path;
1239
1240	/*
1241	 * Set quota enabled flag after committing the transaction, to avoid
1242	 * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot
1243	 * creation.
1244	 */
1245	spin_lock(&fs_info->qgroup_lock);
1246	fs_info->quota_root = quota_root;
1247	set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1248	if (simple)
1249		btrfs_set_fs_incompat(fs_info, SIMPLE_QUOTA);
1250	spin_unlock(&fs_info->qgroup_lock);
1251
1252	/* Skip rescan for simple qgroups. */
1253	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
1254		goto out_free_path;
1255
1256	ret = qgroup_rescan_init(fs_info, 0, 1);
1257	if (!ret) {
1258	        qgroup_rescan_zero_tracking(fs_info);
1259		fs_info->qgroup_rescan_running = true;
1260	        btrfs_queue_work(fs_info->qgroup_rescan_workers,
1261	                         &fs_info->qgroup_rescan_work);
1262	} else {
1263		/*
1264		 * We have set both BTRFS_FS_QUOTA_ENABLED and
1265		 * BTRFS_QGROUP_STATUS_FLAG_ON, so we can only fail with
1266		 * -EINPROGRESS. That can happen because someone started the
1267		 * rescan worker by calling quota rescan ioctl before we
1268		 * attempted to initialize the rescan worker. Failure due to
1269		 * quotas disabled in the meanwhile is not possible, because
1270		 * we are holding a write lock on fs_info->subvol_sem, which
1271		 * is also acquired when disabling quotas.
1272		 * Ignore such error, and any other error would need to undo
1273		 * everything we did in the transaction we just committed.
1274		 */
1275		ASSERT(ret == -EINPROGRESS);
1276		ret = 0;
1277	}
1278
1279out_free_path:
1280	btrfs_free_path(path);
1281out_free_root:
1282	if (ret)
1283		btrfs_put_root(quota_root);
 
 
 
1284out:
1285	if (ret) {
1286		ulist_free(fs_info->qgroup_ulist);
1287		fs_info->qgroup_ulist = NULL;
1288		btrfs_sysfs_del_qgroups(fs_info);
1289	}
1290	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1291	if (ret && trans)
1292		btrfs_end_transaction(trans);
1293	else if (trans)
1294		ret = btrfs_end_transaction(trans);
1295	ulist_free(ulist);
1296	kfree(prealloc);
1297	return ret;
1298}
1299
1300/*
1301 * It is possible to have outstanding ordered extents which reserved bytes
1302 * before we disabled. We need to fully flush delalloc, ordered extents, and a
1303 * commit to ensure that we don't leak such reservations, only to have them
1304 * come back if we re-enable.
1305 *
1306 * - enable simple quotas
1307 * - reserve space
1308 * - release it, store rsv_bytes in OE
1309 * - disable quotas
1310 * - enable simple quotas (qgroup rsv are all 0)
1311 * - OE finishes
1312 * - run delayed refs
1313 * - free rsv_bytes, resulting in miscounting or even underflow
1314 */
1315static int flush_reservations(struct btrfs_fs_info *fs_info)
1316{
1317	struct btrfs_trans_handle *trans;
1318	int ret;
1319
1320	ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
1321	if (ret)
1322		return ret;
1323	btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1324	trans = btrfs_join_transaction(fs_info->tree_root);
1325	if (IS_ERR(trans))
1326		return PTR_ERR(trans);
1327	ret = btrfs_commit_transaction(trans);
1328
1329	return ret;
1330}
1331
1332int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
 
1333{
 
1334	struct btrfs_root *quota_root;
1335	struct btrfs_trans_handle *trans = NULL;
1336	int ret = 0;
1337
1338	/*
1339	 * We need to have subvol_sem write locked to prevent races with
1340	 * snapshot creation.
1341	 */
1342	lockdep_assert_held_write(&fs_info->subvol_sem);
1343
1344	/*
1345	 * Relocation will mess with backrefs, so make sure we have the
1346	 * cleaner_mutex held to protect us from relocate.
1347	 */
1348	lockdep_assert_held(&fs_info->cleaner_mutex);
1349
1350	mutex_lock(&fs_info->qgroup_ioctl_lock);
1351	if (!fs_info->quota_root)
1352		goto out;
1353
1354	/*
1355	 * Unlock the qgroup_ioctl_lock mutex before waiting for the rescan worker to
1356	 * complete. Otherwise we can deadlock because btrfs_remove_qgroup() needs
1357	 * to lock that mutex while holding a transaction handle and the rescan
1358	 * worker needs to commit a transaction.
1359	 */
1360	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1361
1362	/*
1363	 * Request qgroup rescan worker to complete and wait for it. This wait
1364	 * must be done before transaction start for quota disable since it may
1365	 * deadlock with transaction by the qgroup rescan worker.
1366	 */
1367	clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1368	btrfs_qgroup_wait_for_completion(fs_info, false);
1369
1370	/*
1371	 * We have nothing held here and no trans handle, just return the error
1372	 * if there is one.
1373	 */
1374	ret = flush_reservations(fs_info);
1375	if (ret)
1376		return ret;
1377
1378	/*
1379	 * 1 For the root item
1380	 *
1381	 * We should also reserve enough items for the quota tree deletion in
1382	 * btrfs_clean_quota_tree but this is not done.
1383	 *
1384	 * Also, we must always start a transaction without holding the mutex
1385	 * qgroup_ioctl_lock, see btrfs_quota_enable().
1386	 */
1387	trans = btrfs_start_transaction(fs_info->tree_root, 1);
1388
1389	mutex_lock(&fs_info->qgroup_ioctl_lock);
1390	if (IS_ERR(trans)) {
1391		ret = PTR_ERR(trans);
1392		trans = NULL;
1393		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1394		goto out;
1395	}
1396
1397	if (!fs_info->quota_root)
1398		goto out;
1399
1400	spin_lock(&fs_info->qgroup_lock);
1401	quota_root = fs_info->quota_root;
1402	fs_info->quota_root = NULL;
1403	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1404	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1405	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1406	spin_unlock(&fs_info->qgroup_lock);
1407
1408	btrfs_free_qgroup_config(fs_info);
1409
1410	ret = btrfs_clean_quota_tree(trans, quota_root);
1411	if (ret) {
1412		btrfs_abort_transaction(trans, ret);
1413		goto out;
1414	}
1415
1416	ret = btrfs_del_root(trans, &quota_root->root_key);
1417	if (ret) {
1418		btrfs_abort_transaction(trans, ret);
1419		goto out;
1420	}
1421
1422	spin_lock(&fs_info->trans_lock);
1423	list_del(&quota_root->dirty_list);
1424	spin_unlock(&fs_info->trans_lock);
1425
1426	btrfs_tree_lock(quota_root->node);
1427	btrfs_clear_buffer_dirty(trans, quota_root->node);
1428	btrfs_tree_unlock(quota_root->node);
1429	btrfs_free_tree_block(trans, btrfs_root_id(quota_root),
1430			      quota_root->node, 0, 1);
1431
1432	btrfs_put_root(quota_root);
1433
 
 
 
1434out:
1435	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1436	if (ret && trans)
1437		btrfs_end_transaction(trans);
1438	else if (trans)
1439		ret = btrfs_commit_transaction(trans);
1440	return ret;
1441}
1442
1443static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1444			 struct btrfs_qgroup *qgroup)
1445{
1446	if (list_empty(&qgroup->dirty))
1447		list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1448}
1449
1450static void qgroup_iterator_add(struct list_head *head, struct btrfs_qgroup *qgroup)
1451{
1452	if (!list_empty(&qgroup->iterator))
1453		return;
1454
1455	list_add_tail(&qgroup->iterator, head);
1456}
1457
1458static void qgroup_iterator_clean(struct list_head *head)
1459{
1460	while (!list_empty(head)) {
1461		struct btrfs_qgroup *qgroup;
1462
1463		qgroup = list_first_entry(head, struct btrfs_qgroup, iterator);
1464		list_del_init(&qgroup->iterator);
1465	}
1466}
1467
1468/*
1469 * The easy accounting, we're updating qgroup relationship whose child qgroup
1470 * only has exclusive extents.
1471 *
1472 * In this case, all exclusive extents will also be exclusive for parent, so
1473 * excl/rfer just get added/removed.
1474 *
1475 * So is qgroup reservation space, which should also be added/removed to
1476 * parent.
1477 * Or when child tries to release reservation space, parent will underflow its
1478 * reservation (for relationship adding case).
1479 *
1480 * Caller should hold fs_info->qgroup_lock.
1481 */
1482static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info, u64 ref_root,
1483				    struct btrfs_qgroup *src, int sign)
 
1484{
1485	struct btrfs_qgroup *qgroup;
1486	struct btrfs_qgroup *cur;
1487	LIST_HEAD(qgroup_list);
1488	u64 num_bytes = src->excl;
1489	int ret = 0;
1490
1491	qgroup = find_qgroup_rb(fs_info, ref_root);
1492	if (!qgroup)
1493		goto out;
1494
1495	qgroup_iterator_add(&qgroup_list, qgroup);
1496	list_for_each_entry(cur, &qgroup_list, iterator) {
1497		struct btrfs_qgroup_list *glist;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1498
 
 
 
 
1499		qgroup->rfer += sign * num_bytes;
1500		qgroup->rfer_cmpr += sign * num_bytes;
1501
1502		WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1503		qgroup->excl += sign * num_bytes;
 
 
1504		qgroup->excl_cmpr += sign * num_bytes;
1505
1506		if (sign > 0)
1507			qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1508		else
1509			qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1510		qgroup_dirty(fs_info, qgroup);
1511
1512		/* Append parent qgroups to @qgroup_list. */
1513		list_for_each_entry(glist, &qgroup->groups, next_group)
1514			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
 
1515	}
1516	ret = 0;
1517out:
1518	qgroup_iterator_clean(&qgroup_list);
1519	return ret;
1520}
1521
1522
1523/*
1524 * Quick path for updating qgroup with only excl refs.
1525 *
1526 * In that case, just update all parent will be enough.
1527 * Or we needs to do a full rescan.
1528 * Caller should also hold fs_info->qgroup_lock.
1529 *
1530 * Return 0 for quick update, return >0 for need to full rescan
1531 * and mark INCONSISTENT flag.
1532 * Return < 0 for other error.
1533 */
1534static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1535				   u64 src, u64 dst, int sign)
 
1536{
1537	struct btrfs_qgroup *qgroup;
1538	int ret = 1;
1539	int err = 0;
1540
1541	qgroup = find_qgroup_rb(fs_info, src);
1542	if (!qgroup)
1543		goto out;
1544	if (qgroup->excl == qgroup->rfer) {
1545		ret = 0;
1546		err = __qgroup_excl_accounting(fs_info, dst, qgroup, sign);
 
1547		if (err < 0) {
1548			ret = err;
1549			goto out;
1550		}
1551	}
1552out:
1553	if (ret)
1554		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1555	return ret;
1556}
1557
1558int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst)
 
1559{
1560	struct btrfs_fs_info *fs_info = trans->fs_info;
1561	struct btrfs_qgroup *parent;
1562	struct btrfs_qgroup *member;
1563	struct btrfs_qgroup_list *list;
1564	struct btrfs_qgroup_list *prealloc = NULL;
1565	int ret = 0;
1566
1567	/* Check the level of src and dst first */
1568	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1569		return -EINVAL;
1570
 
 
 
 
1571	mutex_lock(&fs_info->qgroup_ioctl_lock);
1572	if (!fs_info->quota_root) {
1573		ret = -ENOTCONN;
 
1574		goto out;
1575	}
1576	member = find_qgroup_rb(fs_info, src);
1577	parent = find_qgroup_rb(fs_info, dst);
1578	if (!member || !parent) {
1579		ret = -EINVAL;
1580		goto out;
1581	}
1582
1583	/* check if such qgroup relation exist firstly */
1584	list_for_each_entry(list, &member->groups, next_group) {
1585		if (list->group == parent) {
1586			ret = -EEXIST;
1587			goto out;
1588		}
1589	}
1590
1591	prealloc = kzalloc(sizeof(*list), GFP_NOFS);
1592	if (!prealloc) {
1593		ret = -ENOMEM;
1594		goto out;
1595	}
1596	ret = add_qgroup_relation_item(trans, src, dst);
1597	if (ret)
1598		goto out;
1599
1600	ret = add_qgroup_relation_item(trans, dst, src);
1601	if (ret) {
1602		del_qgroup_relation_item(trans, src, dst);
1603		goto out;
1604	}
1605
1606	spin_lock(&fs_info->qgroup_lock);
1607	ret = __add_relation_rb(prealloc, member, parent);
1608	prealloc = NULL;
1609	if (ret < 0) {
1610		spin_unlock(&fs_info->qgroup_lock);
1611		goto out;
1612	}
1613	ret = quick_update_accounting(fs_info, src, dst, 1);
1614	spin_unlock(&fs_info->qgroup_lock);
1615out:
1616	kfree(prealloc);
1617	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
1618	return ret;
1619}
1620
1621static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1622				 u64 dst)
1623{
1624	struct btrfs_fs_info *fs_info = trans->fs_info;
1625	struct btrfs_qgroup *parent;
1626	struct btrfs_qgroup *member;
1627	struct btrfs_qgroup_list *list;
1628	bool found = false;
1629	int ret = 0;
1630	int ret2;
 
 
 
 
1631
1632	if (!fs_info->quota_root) {
1633		ret = -ENOTCONN;
 
1634		goto out;
1635	}
1636
1637	member = find_qgroup_rb(fs_info, src);
1638	parent = find_qgroup_rb(fs_info, dst);
1639	/*
1640	 * The parent/member pair doesn't exist, then try to delete the dead
1641	 * relation items only.
1642	 */
1643	if (!member || !parent)
1644		goto delete_item;
1645
1646	/* check if such qgroup relation exist firstly */
1647	list_for_each_entry(list, &member->groups, next_group) {
1648		if (list->group == parent) {
1649			found = true;
1650			break;
1651		}
1652	}
 
 
 
 
 
 
 
1653
1654delete_item:
1655	ret = del_qgroup_relation_item(trans, src, dst);
1656	if (ret < 0 && ret != -ENOENT)
1657		goto out;
1658	ret2 = del_qgroup_relation_item(trans, dst, src);
1659	if (ret2 < 0 && ret2 != -ENOENT)
1660		goto out;
1661
1662	/* At least one deletion succeeded, return 0 */
1663	if (!ret || !ret2)
1664		ret = 0;
1665
1666	if (found) {
1667		spin_lock(&fs_info->qgroup_lock);
1668		del_relation_rb(fs_info, src, dst);
1669		ret = quick_update_accounting(fs_info, src, dst, -1);
1670		spin_unlock(&fs_info->qgroup_lock);
1671	}
1672out:
 
1673	return ret;
1674}
1675
1676int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1677			      u64 dst)
1678{
1679	struct btrfs_fs_info *fs_info = trans->fs_info;
1680	int ret = 0;
1681
1682	mutex_lock(&fs_info->qgroup_ioctl_lock);
1683	ret = __del_qgroup_relation(trans, src, dst);
1684	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1685
1686	return ret;
1687}
1688
1689int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 
1690{
1691	struct btrfs_fs_info *fs_info = trans->fs_info;
1692	struct btrfs_root *quota_root;
1693	struct btrfs_qgroup *qgroup;
1694	struct btrfs_qgroup *prealloc = NULL;
1695	int ret = 0;
1696
1697	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
1698		return 0;
1699
1700	mutex_lock(&fs_info->qgroup_ioctl_lock);
1701	if (!fs_info->quota_root) {
1702		ret = -ENOTCONN;
 
1703		goto out;
1704	}
1705	quota_root = fs_info->quota_root;
1706	qgroup = find_qgroup_rb(fs_info, qgroupid);
1707	if (qgroup) {
1708		ret = -EEXIST;
1709		goto out;
1710	}
1711
1712	prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1713	if (!prealloc) {
1714		ret = -ENOMEM;
1715		goto out;
1716	}
1717
1718	ret = add_qgroup_item(trans, quota_root, qgroupid);
1719	if (ret)
1720		goto out;
1721
1722	spin_lock(&fs_info->qgroup_lock);
1723	qgroup = add_qgroup_rb(fs_info, prealloc, qgroupid);
1724	spin_unlock(&fs_info->qgroup_lock);
1725	prealloc = NULL;
1726
1727	ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
 
1728out:
1729	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1730	kfree(prealloc);
1731	return ret;
1732}
1733
1734static bool qgroup_has_usage(struct btrfs_qgroup *qgroup)
 
1735{
1736	return (qgroup->rfer > 0 || qgroup->rfer_cmpr > 0 ||
1737		qgroup->excl > 0 || qgroup->excl_cmpr > 0 ||
1738		qgroup->rsv.values[BTRFS_QGROUP_RSV_DATA] > 0 ||
1739		qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC] > 0 ||
1740		qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > 0);
1741}
1742
1743int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1744{
1745	struct btrfs_fs_info *fs_info = trans->fs_info;
1746	struct btrfs_qgroup *qgroup;
1747	struct btrfs_qgroup_list *list;
1748	int ret = 0;
1749
1750	mutex_lock(&fs_info->qgroup_ioctl_lock);
1751	if (!fs_info->quota_root) {
1752		ret = -ENOTCONN;
 
1753		goto out;
1754	}
1755
1756	qgroup = find_qgroup_rb(fs_info, qgroupid);
1757	if (!qgroup) {
1758		ret = -ENOENT;
1759		goto out;
 
 
 
 
 
 
1760	}
1761
1762	if (is_fstree(qgroupid) && qgroup_has_usage(qgroup)) {
1763		ret = -EBUSY;
1764		goto out;
1765	}
1766
1767	/* Check if there are no children of this qgroup */
1768	if (!list_empty(&qgroup->members)) {
1769		ret = -EBUSY;
1770		goto out;
1771	}
1772
1773	ret = del_qgroup_item(trans, qgroupid);
1774	if (ret && ret != -ENOENT)
1775		goto out;
1776
1777	while (!list_empty(&qgroup->groups)) {
1778		list = list_first_entry(&qgroup->groups,
1779					struct btrfs_qgroup_list, next_group);
1780		ret = __del_qgroup_relation(trans, qgroupid,
1781					    list->group->qgroupid);
 
1782		if (ret)
1783			goto out;
1784	}
1785
1786	spin_lock(&fs_info->qgroup_lock);
1787	del_qgroup_rb(fs_info, qgroupid);
1788	spin_unlock(&fs_info->qgroup_lock);
1789
1790	/*
1791	 * Remove the qgroup from sysfs now without holding the qgroup_lock
1792	 * spinlock, since the sysfs_remove_group() function needs to take
1793	 * the mutex kernfs_mutex through kernfs_remove_by_name_ns().
1794	 */
1795	btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1796	kfree(qgroup);
1797out:
1798	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1799	return ret;
1800}
1801
1802int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
 
1803		       struct btrfs_qgroup_limit *limit)
1804{
1805	struct btrfs_fs_info *fs_info = trans->fs_info;
1806	struct btrfs_qgroup *qgroup;
1807	int ret = 0;
1808	/* Sometimes we would want to clear the limit on this qgroup.
1809	 * To meet this requirement, we treat the -1 as a special value
1810	 * which tell kernel to clear the limit on this qgroup.
1811	 */
1812	const u64 CLEAR_VALUE = -1;
1813
1814	mutex_lock(&fs_info->qgroup_ioctl_lock);
1815	if (!fs_info->quota_root) {
1816		ret = -ENOTCONN;
 
1817		goto out;
1818	}
1819
1820	qgroup = find_qgroup_rb(fs_info, qgroupid);
1821	if (!qgroup) {
1822		ret = -ENOENT;
1823		goto out;
1824	}
1825
1826	spin_lock(&fs_info->qgroup_lock);
1827	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1828		if (limit->max_rfer == CLEAR_VALUE) {
1829			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1830			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1831			qgroup->max_rfer = 0;
1832		} else {
1833			qgroup->max_rfer = limit->max_rfer;
1834		}
1835	}
1836	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1837		if (limit->max_excl == CLEAR_VALUE) {
1838			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1839			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1840			qgroup->max_excl = 0;
1841		} else {
1842			qgroup->max_excl = limit->max_excl;
1843		}
1844	}
1845	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1846		if (limit->rsv_rfer == CLEAR_VALUE) {
1847			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1848			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1849			qgroup->rsv_rfer = 0;
1850		} else {
1851			qgroup->rsv_rfer = limit->rsv_rfer;
1852		}
1853	}
1854	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1855		if (limit->rsv_excl == CLEAR_VALUE) {
1856			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1857			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1858			qgroup->rsv_excl = 0;
1859		} else {
1860			qgroup->rsv_excl = limit->rsv_excl;
1861		}
1862	}
1863	qgroup->lim_flags |= limit->flags;
1864
1865	spin_unlock(&fs_info->qgroup_lock);
1866
1867	ret = update_qgroup_limit_item(trans, qgroup);
1868	if (ret) {
1869		qgroup_mark_inconsistent(fs_info);
1870		btrfs_info(fs_info, "unable to update quota limit for %llu",
1871		       qgroupid);
1872	}
1873
1874out:
1875	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1876	return ret;
1877}
1878
1879/*
1880 * Inform qgroup to trace one dirty extent, its info is recorded in @record.
1881 * So qgroup can account it at transaction committing time.
1882 *
1883 * No lock version, caller must acquire delayed ref lock and allocated memory,
1884 * then call btrfs_qgroup_trace_extent_post() after exiting lock context.
1885 *
1886 * Return 0 for success insert
1887 * Return >0 for existing record, caller can free @record safely.
1888 * Error is not possible
1889 */
1890int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1891				struct btrfs_delayed_ref_root *delayed_refs,
1892				struct btrfs_qgroup_extent_record *record)
1893{
1894	struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1895	struct rb_node *parent_node = NULL;
1896	struct btrfs_qgroup_extent_record *entry;
1897	u64 bytenr = record->bytenr;
1898
1899	if (!btrfs_qgroup_full_accounting(fs_info))
1900		return 1;
1901
1902	lockdep_assert_held(&delayed_refs->lock);
1903	trace_btrfs_qgroup_trace_extent(fs_info, record);
1904
1905	while (*p) {
1906		parent_node = *p;
1907		entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1908				 node);
1909		if (bytenr < entry->bytenr) {
1910			p = &(*p)->rb_left;
1911		} else if (bytenr > entry->bytenr) {
1912			p = &(*p)->rb_right;
1913		} else {
1914			if (record->data_rsv && !entry->data_rsv) {
1915				entry->data_rsv = record->data_rsv;
1916				entry->data_rsv_refroot =
1917					record->data_rsv_refroot;
1918			}
1919			return 1;
1920		}
1921	}
1922
1923	rb_link_node(&record->node, parent_node, p);
1924	rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1925	return 0;
1926}
1927
1928/*
1929 * Post handler after qgroup_trace_extent_nolock().
1930 *
1931 * NOTE: Current qgroup does the expensive backref walk at transaction
1932 * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming
1933 * new transaction.
1934 * This is designed to allow btrfs_find_all_roots() to get correct new_roots
1935 * result.
1936 *
1937 * However for old_roots there is no need to do backref walk at that time,
1938 * since we search commit roots to walk backref and result will always be
1939 * correct.
1940 *
1941 * Due to the nature of no lock version, we can't do backref there.
1942 * So we must call btrfs_qgroup_trace_extent_post() after exiting
1943 * spinlock context.
1944 *
1945 * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result
1946 * using current root, then we can move all expensive backref walk out of
1947 * transaction committing, but not now as qgroup accounting will be wrong again.
1948 */
1949int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans,
1950				   struct btrfs_qgroup_extent_record *qrecord)
1951{
1952	struct btrfs_backref_walk_ctx ctx = { 0 };
1953	int ret;
1954
1955	if (!btrfs_qgroup_full_accounting(trans->fs_info))
1956		return 0;
1957	/*
1958	 * We are always called in a context where we are already holding a
1959	 * transaction handle. Often we are called when adding a data delayed
1960	 * reference from btrfs_truncate_inode_items() (truncating or unlinking),
1961	 * in which case we will be holding a write lock on extent buffer from a
1962	 * subvolume tree. In this case we can't allow btrfs_find_all_roots() to
1963	 * acquire fs_info->commit_root_sem, because that is a higher level lock
1964	 * that must be acquired before locking any extent buffers.
1965	 *
1966	 * So we want btrfs_find_all_roots() to not acquire the commit_root_sem
1967	 * but we can't pass it a non-NULL transaction handle, because otherwise
1968	 * it would not use commit roots and would lock extent buffers, causing
1969	 * a deadlock if it ends up trying to read lock the same extent buffer
1970	 * that was previously write locked at btrfs_truncate_inode_items().
1971	 *
1972	 * So pass a NULL transaction handle to btrfs_find_all_roots() and
1973	 * explicitly tell it to not acquire the commit_root_sem - if we are
1974	 * holding a transaction handle we don't need its protection.
1975	 */
1976	ASSERT(trans != NULL);
1977
1978	if (trans->fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
1979		return 0;
1980
1981	ctx.bytenr = qrecord->bytenr;
1982	ctx.fs_info = trans->fs_info;
1983
1984	ret = btrfs_find_all_roots(&ctx, true);
1985	if (ret < 0) {
1986		qgroup_mark_inconsistent(trans->fs_info);
1987		btrfs_warn(trans->fs_info,
1988"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1989			ret);
1990		return 0;
1991	}
1992
1993	/*
1994	 * Here we don't need to get the lock of
1995	 * trans->transaction->delayed_refs, since inserted qrecord won't
1996	 * be deleted, only qrecord->node may be modified (new qrecord insert)
1997	 *
1998	 * So modifying qrecord->old_roots is safe here
1999	 */
2000	qrecord->old_roots = ctx.roots;
2001	return 0;
2002}
2003
2004/*
2005 * Inform qgroup to trace one dirty extent, specified by @bytenr and
2006 * @num_bytes.
2007 * So qgroup can account it at commit trans time.
2008 *
2009 * Better encapsulated version, with memory allocation and backref walk for
2010 * commit roots.
2011 * So this can sleep.
2012 *
2013 * Return 0 if the operation is done.
2014 * Return <0 for error, like memory allocation failure or invalid parameter
2015 * (NULL trans)
2016 */
2017int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2018			      u64 num_bytes)
2019{
2020	struct btrfs_fs_info *fs_info = trans->fs_info;
2021	struct btrfs_qgroup_extent_record *record;
2022	struct btrfs_delayed_ref_root *delayed_refs;
2023	int ret;
2024
2025	if (!btrfs_qgroup_full_accounting(fs_info) || bytenr == 0 || num_bytes == 0)
2026		return 0;
2027	record = kzalloc(sizeof(*record), GFP_NOFS);
2028	if (!record)
2029		return -ENOMEM;
2030
2031	delayed_refs = &trans->transaction->delayed_refs;
2032	record->bytenr = bytenr;
2033	record->num_bytes = num_bytes;
2034	record->old_roots = NULL;
2035
2036	spin_lock(&delayed_refs->lock);
2037	ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
2038	spin_unlock(&delayed_refs->lock);
2039	if (ret > 0) {
2040		kfree(record);
2041		return 0;
2042	}
2043	return btrfs_qgroup_trace_extent_post(trans, record);
2044}
2045
2046/*
2047 * Inform qgroup to trace all leaf items of data
2048 *
2049 * Return 0 for success
2050 * Return <0 for error(ENOMEM)
2051 */
2052int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
2053				  struct extent_buffer *eb)
2054{
2055	struct btrfs_fs_info *fs_info = trans->fs_info;
2056	int nr = btrfs_header_nritems(eb);
2057	int i, extent_type, ret;
2058	struct btrfs_key key;
2059	struct btrfs_file_extent_item *fi;
2060	u64 bytenr, num_bytes;
2061
2062	/* We can be called directly from walk_up_proc() */
2063	if (!btrfs_qgroup_full_accounting(fs_info))
2064		return 0;
2065
2066	for (i = 0; i < nr; i++) {
2067		btrfs_item_key_to_cpu(eb, &key, i);
2068
2069		if (key.type != BTRFS_EXTENT_DATA_KEY)
2070			continue;
2071
2072		fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
2073		/* filter out non qgroup-accountable extents  */
2074		extent_type = btrfs_file_extent_type(eb, fi);
2075
2076		if (extent_type == BTRFS_FILE_EXTENT_INLINE)
2077			continue;
2078
2079		bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
2080		if (!bytenr)
2081			continue;
2082
2083		num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
2084
2085		ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes);
2086		if (ret)
2087			return ret;
2088	}
2089	cond_resched();
2090	return 0;
2091}
2092
2093/*
2094 * Walk up the tree from the bottom, freeing leaves and any interior
2095 * nodes which have had all slots visited. If a node (leaf or
2096 * interior) is freed, the node above it will have it's slot
2097 * incremented. The root node will never be freed.
2098 *
2099 * At the end of this function, we should have a path which has all
2100 * slots incremented to the next position for a search. If we need to
2101 * read a new node it will be NULL and the node above it will have the
2102 * correct slot selected for a later read.
2103 *
2104 * If we increment the root nodes slot counter past the number of
2105 * elements, 1 is returned to signal completion of the search.
2106 */
2107static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
2108{
2109	int level = 0;
2110	int nr, slot;
2111	struct extent_buffer *eb;
2112
2113	if (root_level == 0)
2114		return 1;
2115
2116	while (level <= root_level) {
2117		eb = path->nodes[level];
2118		nr = btrfs_header_nritems(eb);
2119		path->slots[level]++;
2120		slot = path->slots[level];
2121		if (slot >= nr || level == 0) {
2122			/*
2123			 * Don't free the root -  we will detect this
2124			 * condition after our loop and return a
2125			 * positive value for caller to stop walking the tree.
2126			 */
2127			if (level != root_level) {
2128				btrfs_tree_unlock_rw(eb, path->locks[level]);
2129				path->locks[level] = 0;
2130
2131				free_extent_buffer(eb);
2132				path->nodes[level] = NULL;
2133				path->slots[level] = 0;
2134			}
2135		} else {
2136			/*
2137			 * We have a valid slot to walk back down
2138			 * from. Stop here so caller can process these
2139			 * new nodes.
2140			 */
2141			break;
2142		}
2143
2144		level++;
2145	}
2146
2147	eb = path->nodes[root_level];
2148	if (path->slots[root_level] >= btrfs_header_nritems(eb))
2149		return 1;
2150
2151	return 0;
2152}
2153
2154/*
2155 * Helper function to trace a subtree tree block swap.
2156 *
2157 * The swap will happen in highest tree block, but there may be a lot of
2158 * tree blocks involved.
2159 *
2160 * For example:
2161 *  OO = Old tree blocks
2162 *  NN = New tree blocks allocated during balance
2163 *
2164 *           File tree (257)                  Reloc tree for 257
2165 * L2              OO                                NN
2166 *               /    \                            /    \
2167 * L1          OO      OO (a)                    OO      NN (a)
2168 *            / \     / \                       / \     / \
2169 * L0       OO   OO OO   OO                   OO   OO NN   NN
2170 *                  (b)  (c)                          (b)  (c)
2171 *
2172 * When calling qgroup_trace_extent_swap(), we will pass:
2173 * @src_eb = OO(a)
2174 * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
2175 * @dst_level = 0
2176 * @root_level = 1
2177 *
2178 * In that case, qgroup_trace_extent_swap() will search from OO(a) to
2179 * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
2180 *
2181 * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
2182 *
2183 * 1) Tree search from @src_eb
2184 *    It should acts as a simplified btrfs_search_slot().
2185 *    The key for search can be extracted from @dst_path->nodes[dst_level]
2186 *    (first key).
2187 *
2188 * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
2189 *    NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
2190 *    They should be marked during previous (@dst_level = 1) iteration.
2191 *
2192 * 3) Mark file extents in leaves dirty
2193 *    We don't have good way to pick out new file extents only.
2194 *    So we still follow the old method by scanning all file extents in
2195 *    the leave.
2196 *
2197 * This function can free us from keeping two paths, thus later we only need
2198 * to care about how to iterate all new tree blocks in reloc tree.
2199 */
2200static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
2201				    struct extent_buffer *src_eb,
2202				    struct btrfs_path *dst_path,
2203				    int dst_level, int root_level,
2204				    bool trace_leaf)
2205{
2206	struct btrfs_key key;
2207	struct btrfs_path *src_path;
2208	struct btrfs_fs_info *fs_info = trans->fs_info;
2209	u32 nodesize = fs_info->nodesize;
2210	int cur_level = root_level;
2211	int ret;
2212
2213	BUG_ON(dst_level > root_level);
2214	/* Level mismatch */
2215	if (btrfs_header_level(src_eb) != root_level)
2216		return -EINVAL;
2217
2218	src_path = btrfs_alloc_path();
2219	if (!src_path) {
2220		ret = -ENOMEM;
2221		goto out;
2222	}
2223
2224	if (dst_level)
2225		btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2226	else
2227		btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2228
2229	/* For src_path */
2230	atomic_inc(&src_eb->refs);
2231	src_path->nodes[root_level] = src_eb;
2232	src_path->slots[root_level] = dst_path->slots[root_level];
2233	src_path->locks[root_level] = 0;
2234
2235	/* A simplified version of btrfs_search_slot() */
2236	while (cur_level >= dst_level) {
2237		struct btrfs_key src_key;
2238		struct btrfs_key dst_key;
2239
2240		if (src_path->nodes[cur_level] == NULL) {
2241			struct extent_buffer *eb;
2242			int parent_slot;
2243
2244			eb = src_path->nodes[cur_level + 1];
2245			parent_slot = src_path->slots[cur_level + 1];
2246
2247			eb = btrfs_read_node_slot(eb, parent_slot);
2248			if (IS_ERR(eb)) {
2249				ret = PTR_ERR(eb);
2250				goto out;
2251			}
2252
2253			src_path->nodes[cur_level] = eb;
2254
2255			btrfs_tree_read_lock(eb);
2256			src_path->locks[cur_level] = BTRFS_READ_LOCK;
2257		}
2258
2259		src_path->slots[cur_level] = dst_path->slots[cur_level];
2260		if (cur_level) {
2261			btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
2262					&dst_key, dst_path->slots[cur_level]);
2263			btrfs_node_key_to_cpu(src_path->nodes[cur_level],
2264					&src_key, src_path->slots[cur_level]);
2265		} else {
2266			btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
2267					&dst_key, dst_path->slots[cur_level]);
2268			btrfs_item_key_to_cpu(src_path->nodes[cur_level],
2269					&src_key, src_path->slots[cur_level]);
2270		}
2271		/* Content mismatch, something went wrong */
2272		if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
2273			ret = -ENOENT;
2274			goto out;
2275		}
2276		cur_level--;
2277	}
2278
2279	/*
2280	 * Now both @dst_path and @src_path have been populated, record the tree
2281	 * blocks for qgroup accounting.
2282	 */
2283	ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
2284					nodesize);
2285	if (ret < 0)
2286		goto out;
2287	ret = btrfs_qgroup_trace_extent(trans, dst_path->nodes[dst_level]->start,
2288					nodesize);
2289	if (ret < 0)
2290		goto out;
2291
2292	/* Record leaf file extents */
2293	if (dst_level == 0 && trace_leaf) {
2294		ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
2295		if (ret < 0)
2296			goto out;
2297		ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
2298	}
2299out:
2300	btrfs_free_path(src_path);
2301	return ret;
2302}
2303
2304/*
2305 * Helper function to do recursive generation-aware depth-first search, to
2306 * locate all new tree blocks in a subtree of reloc tree.
2307 *
2308 * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
2309 *         reloc tree
2310 * L2         NN (a)
2311 *          /    \
2312 * L1    OO        NN (b)
2313 *      /  \      /  \
2314 * L0  OO  OO    OO  NN
2315 *               (c) (d)
2316 * If we pass:
2317 * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
2318 * @cur_level = 1
2319 * @root_level = 1
2320 *
2321 * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
2322 * above tree blocks along with their counter parts in file tree.
2323 * While during search, old tree blocks OO(c) will be skipped as tree block swap
2324 * won't affect OO(c).
2325 */
2326static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
2327					   struct extent_buffer *src_eb,
2328					   struct btrfs_path *dst_path,
2329					   int cur_level, int root_level,
2330					   u64 last_snapshot, bool trace_leaf)
2331{
2332	struct btrfs_fs_info *fs_info = trans->fs_info;
2333	struct extent_buffer *eb;
2334	bool need_cleanup = false;
2335	int ret = 0;
2336	int i;
2337
2338	/* Level sanity check */
2339	if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 ||
2340	    root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 ||
2341	    root_level < cur_level) {
2342		btrfs_err_rl(fs_info,
2343			"%s: bad levels, cur_level=%d root_level=%d",
2344			__func__, cur_level, root_level);
2345		return -EUCLEAN;
2346	}
2347
2348	/* Read the tree block if needed */
2349	if (dst_path->nodes[cur_level] == NULL) {
2350		int parent_slot;
2351		u64 child_gen;
2352
2353		/*
2354		 * dst_path->nodes[root_level] must be initialized before
2355		 * calling this function.
2356		 */
2357		if (cur_level == root_level) {
2358			btrfs_err_rl(fs_info,
2359	"%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
2360				__func__, root_level, root_level, cur_level);
2361			return -EUCLEAN;
2362		}
2363
2364		/*
2365		 * We need to get child blockptr/gen from parent before we can
2366		 * read it.
2367		  */
2368		eb = dst_path->nodes[cur_level + 1];
2369		parent_slot = dst_path->slots[cur_level + 1];
2370		child_gen = btrfs_node_ptr_generation(eb, parent_slot);
2371
2372		/* This node is old, no need to trace */
2373		if (child_gen < last_snapshot)
2374			goto out;
2375
2376		eb = btrfs_read_node_slot(eb, parent_slot);
2377		if (IS_ERR(eb)) {
2378			ret = PTR_ERR(eb);
2379			goto out;
2380		}
2381
2382		dst_path->nodes[cur_level] = eb;
2383		dst_path->slots[cur_level] = 0;
2384
2385		btrfs_tree_read_lock(eb);
2386		dst_path->locks[cur_level] = BTRFS_READ_LOCK;
2387		need_cleanup = true;
2388	}
2389
2390	/* Now record this tree block and its counter part for qgroups */
2391	ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
2392				       root_level, trace_leaf);
2393	if (ret < 0)
2394		goto cleanup;
2395
2396	eb = dst_path->nodes[cur_level];
2397
2398	if (cur_level > 0) {
2399		/* Iterate all child tree blocks */
2400		for (i = 0; i < btrfs_header_nritems(eb); i++) {
2401			/* Skip old tree blocks as they won't be swapped */
2402			if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
2403				continue;
2404			dst_path->slots[cur_level] = i;
2405
2406			/* Recursive call (at most 7 times) */
2407			ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
2408					dst_path, cur_level - 1, root_level,
2409					last_snapshot, trace_leaf);
2410			if (ret < 0)
2411				goto cleanup;
2412		}
2413	}
2414
2415cleanup:
2416	if (need_cleanup) {
2417		/* Clean up */
2418		btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2419				     dst_path->locks[cur_level]);
2420		free_extent_buffer(dst_path->nodes[cur_level]);
2421		dst_path->nodes[cur_level] = NULL;
2422		dst_path->slots[cur_level] = 0;
2423		dst_path->locks[cur_level] = 0;
2424	}
2425out:
2426	return ret;
2427}
2428
2429static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2430				struct extent_buffer *src_eb,
2431				struct extent_buffer *dst_eb,
2432				u64 last_snapshot, bool trace_leaf)
2433{
2434	struct btrfs_fs_info *fs_info = trans->fs_info;
2435	struct btrfs_path *dst_path = NULL;
2436	int level;
2437	int ret;
2438
2439	if (!btrfs_qgroup_full_accounting(fs_info))
2440		return 0;
2441
2442	/* Wrong parameter order */
2443	if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) {
2444		btrfs_err_rl(fs_info,
2445		"%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2446			     btrfs_header_generation(src_eb),
2447			     btrfs_header_generation(dst_eb));
2448		return -EUCLEAN;
2449	}
2450
2451	if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2452		ret = -EIO;
2453		goto out;
2454	}
2455
2456	level = btrfs_header_level(dst_eb);
2457	dst_path = btrfs_alloc_path();
2458	if (!dst_path) {
2459		ret = -ENOMEM;
2460		goto out;
2461	}
2462	/* For dst_path */
2463	atomic_inc(&dst_eb->refs);
2464	dst_path->nodes[level] = dst_eb;
2465	dst_path->slots[level] = 0;
2466	dst_path->locks[level] = 0;
2467
2468	/* Do the generation aware breadth-first search */
2469	ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2470					      level, last_snapshot, trace_leaf);
2471	if (ret < 0)
2472		goto out;
2473	ret = 0;
2474
2475out:
2476	btrfs_free_path(dst_path);
2477	if (ret < 0)
2478		qgroup_mark_inconsistent(fs_info);
2479	return ret;
2480}
2481
2482/*
2483 * Inform qgroup to trace a whole subtree, including all its child tree
2484 * blocks and data.
2485 * The root tree block is specified by @root_eb.
2486 *
2487 * Normally used by relocation(tree block swap) and subvolume deletion.
2488 *
2489 * Return 0 for success
2490 * Return <0 for error(ENOMEM or tree search error)
2491 */
2492int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
2493			       struct extent_buffer *root_eb,
2494			       u64 root_gen, int root_level)
2495{
2496	struct btrfs_fs_info *fs_info = trans->fs_info;
2497	int ret = 0;
2498	int level;
2499	u8 drop_subptree_thres;
2500	struct extent_buffer *eb = root_eb;
2501	struct btrfs_path *path = NULL;
2502
2503	ASSERT(0 <= root_level && root_level < BTRFS_MAX_LEVEL);
2504	ASSERT(root_eb != NULL);
2505
2506	if (!btrfs_qgroup_full_accounting(fs_info))
2507		return 0;
2508
2509	spin_lock(&fs_info->qgroup_lock);
2510	drop_subptree_thres = fs_info->qgroup_drop_subtree_thres;
2511	spin_unlock(&fs_info->qgroup_lock);
2512
2513	/*
2514	 * This function only gets called for snapshot drop, if we hit a high
2515	 * node here, it means we are going to change ownership for quite a lot
2516	 * of extents, which will greatly slow down btrfs_commit_transaction().
2517	 *
2518	 * So here if we find a high tree here, we just skip the accounting and
2519	 * mark qgroup inconsistent.
2520	 */
2521	if (root_level >= drop_subptree_thres) {
2522		qgroup_mark_inconsistent(fs_info);
2523		return 0;
2524	}
2525
2526	if (!extent_buffer_uptodate(root_eb)) {
2527		struct btrfs_tree_parent_check check = {
2528			.has_first_key = false,
2529			.transid = root_gen,
2530			.level = root_level
2531		};
2532
2533		ret = btrfs_read_extent_buffer(root_eb, &check);
2534		if (ret)
2535			goto out;
2536	}
2537
2538	if (root_level == 0) {
2539		ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2540		goto out;
2541	}
2542
2543	path = btrfs_alloc_path();
2544	if (!path)
2545		return -ENOMEM;
2546
2547	/*
2548	 * Walk down the tree.  Missing extent blocks are filled in as
2549	 * we go. Metadata is accounted every time we read a new
2550	 * extent block.
2551	 *
2552	 * When we reach a leaf, we account for file extent items in it,
2553	 * walk back up the tree (adjusting slot pointers as we go)
2554	 * and restart the search process.
2555	 */
2556	atomic_inc(&root_eb->refs);	/* For path */
2557	path->nodes[root_level] = root_eb;
2558	path->slots[root_level] = 0;
2559	path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2560walk_down:
2561	level = root_level;
2562	while (level >= 0) {
2563		if (path->nodes[level] == NULL) {
2564			int parent_slot;
2565			u64 child_bytenr;
2566
2567			/*
2568			 * We need to get child blockptr from parent before we
2569			 * can read it.
2570			  */
2571			eb = path->nodes[level + 1];
2572			parent_slot = path->slots[level + 1];
2573			child_bytenr = btrfs_node_blockptr(eb, parent_slot);
2574
2575			eb = btrfs_read_node_slot(eb, parent_slot);
2576			if (IS_ERR(eb)) {
2577				ret = PTR_ERR(eb);
2578				goto out;
2579			}
2580
2581			path->nodes[level] = eb;
2582			path->slots[level] = 0;
2583
2584			btrfs_tree_read_lock(eb);
2585			path->locks[level] = BTRFS_READ_LOCK;
2586
2587			ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2588							fs_info->nodesize);
2589			if (ret)
2590				goto out;
2591		}
2592
2593		if (level == 0) {
2594			ret = btrfs_qgroup_trace_leaf_items(trans,
2595							    path->nodes[level]);
2596			if (ret)
2597				goto out;
2598
2599			/* Nonzero return here means we completed our search */
2600			ret = adjust_slots_upwards(path, root_level);
2601			if (ret)
2602				break;
2603
2604			/* Restart search with new slots */
2605			goto walk_down;
2606		}
2607
2608		level--;
2609	}
2610
2611	ret = 0;
2612out:
2613	btrfs_free_path(path);
2614
2615	return ret;
2616}
2617
2618static void qgroup_iterator_nested_add(struct list_head *head, struct btrfs_qgroup *qgroup)
2619{
2620	if (!list_empty(&qgroup->nested_iterator))
2621		return;
2622
2623	list_add_tail(&qgroup->nested_iterator, head);
2624}
2625
2626static void qgroup_iterator_nested_clean(struct list_head *head)
2627{
2628	while (!list_empty(head)) {
2629		struct btrfs_qgroup *qgroup;
2630
2631		qgroup = list_first_entry(head, struct btrfs_qgroup, nested_iterator);
2632		list_del_init(&qgroup->nested_iterator);
2633	}
2634}
2635
2636#define UPDATE_NEW	0
2637#define UPDATE_OLD	1
2638/*
2639 * Walk all of the roots that points to the bytenr and adjust their refcnts.
2640 */
2641static void qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2642				 struct ulist *roots, struct list_head *qgroups,
2643				 u64 seq, int update_old)
2644{
2645	struct ulist_node *unode;
2646	struct ulist_iterator uiter;
 
 
2647	struct btrfs_qgroup *qg;
 
2648
2649	if (!roots)
2650		return;
2651	ULIST_ITER_INIT(&uiter);
2652	while ((unode = ulist_next(roots, &uiter))) {
2653		LIST_HEAD(tmp);
2654
2655		qg = find_qgroup_rb(fs_info, unode->val);
2656		if (!qg)
2657			continue;
2658
2659		qgroup_iterator_nested_add(qgroups, qg);
2660		qgroup_iterator_add(&tmp, qg);
2661		list_for_each_entry(qg, &tmp, iterator) {
 
 
 
 
 
 
 
2662			struct btrfs_qgroup_list *glist;
2663
 
2664			if (update_old)
2665				btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2666			else
2667				btrfs_qgroup_update_new_refcnt(qg, seq, 1);
2668
2669			list_for_each_entry(glist, &qg->groups, next_group) {
2670				qgroup_iterator_nested_add(qgroups, glist->group);
2671				qgroup_iterator_add(&tmp, glist->group);
 
 
 
 
 
 
 
 
2672			}
2673		}
2674		qgroup_iterator_clean(&tmp);
2675	}
 
2676}
2677
2678/*
2679 * Update qgroup rfer/excl counters.
2680 * Rfer update is easy, codes can explain themselves.
2681 *
2682 * Excl update is tricky, the update is split into 2 parts.
2683 * Part 1: Possible exclusive <-> sharing detect:
2684 *	|	A	|	!A	|
2685 *  -------------------------------------
2686 *  B	|	*	|	-	|
2687 *  -------------------------------------
2688 *  !B	|	+	|	**	|
2689 *  -------------------------------------
2690 *
2691 * Conditions:
2692 * A:	cur_old_roots < nr_old_roots	(not exclusive before)
2693 * !A:	cur_old_roots == nr_old_roots	(possible exclusive before)
2694 * B:	cur_new_roots < nr_new_roots	(not exclusive now)
2695 * !B:	cur_new_roots == nr_new_roots	(possible exclusive now)
2696 *
2697 * Results:
2698 * +: Possible sharing -> exclusive	-: Possible exclusive -> sharing
2699 * *: Definitely not changed.		**: Possible unchanged.
2700 *
2701 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2702 *
2703 * To make the logic clear, we first use condition A and B to split
2704 * combination into 4 results.
2705 *
2706 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2707 * only on variant maybe 0.
2708 *
2709 * Lastly, check result **, since there are 2 variants maybe 0, split them
2710 * again(2x2).
2711 * But this time we don't need to consider other things, the codes and logic
2712 * is easy to understand now.
2713 */
2714static void qgroup_update_counters(struct btrfs_fs_info *fs_info,
2715				   struct list_head *qgroups, u64 nr_old_roots,
2716				   u64 nr_new_roots, u64 num_bytes, u64 seq)
 
 
2717{
 
 
2718	struct btrfs_qgroup *qg;
 
2719
2720	list_for_each_entry(qg, qgroups, nested_iterator) {
2721		u64 cur_new_count, cur_old_count;
2722		bool dirty = false;
2723
 
2724		cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2725		cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2726
2727		trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2728					     cur_new_count);
2729
2730		/* Rfer update part */
2731		if (cur_old_count == 0 && cur_new_count > 0) {
2732			qg->rfer += num_bytes;
2733			qg->rfer_cmpr += num_bytes;
2734			dirty = true;
2735		}
2736		if (cur_old_count > 0 && cur_new_count == 0) {
2737			qg->rfer -= num_bytes;
2738			qg->rfer_cmpr -= num_bytes;
2739			dirty = true;
2740		}
2741
2742		/* Excl update part */
2743		/* Exclusive/none -> shared case */
2744		if (cur_old_count == nr_old_roots &&
2745		    cur_new_count < nr_new_roots) {
2746			/* Exclusive -> shared */
2747			if (cur_old_count != 0) {
2748				qg->excl -= num_bytes;
2749				qg->excl_cmpr -= num_bytes;
2750				dirty = true;
2751			}
2752		}
2753
2754		/* Shared -> exclusive/none case */
2755		if (cur_old_count < nr_old_roots &&
2756		    cur_new_count == nr_new_roots) {
2757			/* Shared->exclusive */
2758			if (cur_new_count != 0) {
2759				qg->excl += num_bytes;
2760				qg->excl_cmpr += num_bytes;
2761				dirty = true;
2762			}
2763		}
2764
2765		/* Exclusive/none -> exclusive/none case */
2766		if (cur_old_count == nr_old_roots &&
2767		    cur_new_count == nr_new_roots) {
2768			if (cur_old_count == 0) {
2769				/* None -> exclusive/none */
2770
2771				if (cur_new_count != 0) {
2772					/* None -> exclusive */
2773					qg->excl += num_bytes;
2774					qg->excl_cmpr += num_bytes;
2775					dirty = true;
2776				}
2777				/* None -> none, nothing changed */
2778			} else {
2779				/* Exclusive -> exclusive/none */
2780
2781				if (cur_new_count == 0) {
2782					/* Exclusive -> none */
2783					qg->excl -= num_bytes;
2784					qg->excl_cmpr -= num_bytes;
2785					dirty = true;
2786				}
2787				/* Exclusive -> exclusive, nothing changed */
2788			}
2789		}
2790
2791		if (dirty)
2792			qgroup_dirty(fs_info, qg);
2793	}
 
2794}
2795
2796/*
2797 * Check if the @roots potentially is a list of fs tree roots
2798 *
2799 * Return 0 for definitely not a fs/subvol tree roots ulist
2800 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2801 *          one as well)
2802 */
2803static int maybe_fs_roots(struct ulist *roots)
2804{
2805	struct ulist_node *unode;
2806	struct ulist_iterator uiter;
2807
2808	/* Empty one, still possible for fs roots */
2809	if (!roots || roots->nnodes == 0)
2810		return 1;
2811
2812	ULIST_ITER_INIT(&uiter);
2813	unode = ulist_next(roots, &uiter);
2814	if (!unode)
2815		return 1;
2816
2817	/*
2818	 * If it contains fs tree roots, then it must belong to fs/subvol
2819	 * trees.
2820	 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2821	 */
2822	return is_fstree(unode->val);
2823}
2824
2825int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2826				u64 num_bytes, struct ulist *old_roots,
2827				struct ulist *new_roots)
2828{
2829	struct btrfs_fs_info *fs_info = trans->fs_info;
2830	LIST_HEAD(qgroups);
2831	u64 seq;
2832	u64 nr_new_roots = 0;
2833	u64 nr_old_roots = 0;
2834	int ret = 0;
2835
2836	/*
2837	 * If quotas get disabled meanwhile, the resources need to be freed and
2838	 * we can't just exit here.
2839	 */
2840	if (!btrfs_qgroup_full_accounting(fs_info) ||
2841	    fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
2842		goto out_free;
2843
2844	if (new_roots) {
2845		if (!maybe_fs_roots(new_roots))
2846			goto out_free;
2847		nr_new_roots = new_roots->nnodes;
2848	}
2849	if (old_roots) {
2850		if (!maybe_fs_roots(old_roots))
2851			goto out_free;
2852		nr_old_roots = old_roots->nnodes;
2853	}
2854
2855	/* Quick exit, either not fs tree roots, or won't affect any qgroup */
2856	if (nr_old_roots == 0 && nr_new_roots == 0)
2857		goto out_free;
 
 
 
 
2858
2859	trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2860					num_bytes, nr_old_roots, nr_new_roots);
 
 
 
 
 
 
 
 
2861
2862	mutex_lock(&fs_info->qgroup_rescan_lock);
2863	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2864		if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2865			mutex_unlock(&fs_info->qgroup_rescan_lock);
2866			ret = 0;
2867			goto out_free;
2868		}
2869	}
2870	mutex_unlock(&fs_info->qgroup_rescan_lock);
2871
2872	spin_lock(&fs_info->qgroup_lock);
2873	seq = fs_info->qgroup_seq;
2874
2875	/* Update old refcnts using old_roots */
2876	qgroup_update_refcnt(fs_info, old_roots, &qgroups, seq, UPDATE_OLD);
 
 
 
2877
2878	/* Update new refcnts using new_roots */
2879	qgroup_update_refcnt(fs_info, new_roots, &qgroups, seq, UPDATE_NEW);
 
 
 
2880
2881	qgroup_update_counters(fs_info, &qgroups, nr_old_roots, nr_new_roots,
2882			       num_bytes, seq);
2883
2884	/*
2885	 * We're done using the iterator, release all its qgroups while holding
2886	 * fs_info->qgroup_lock so that we don't race with btrfs_remove_qgroup()
2887	 * and trigger use-after-free accesses to qgroups.
2888	 */
2889	qgroup_iterator_nested_clean(&qgroups);
2890
2891	/*
2892	 * Bump qgroup_seq to avoid seq overlap
2893	 */
2894	fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
 
2895	spin_unlock(&fs_info->qgroup_lock);
2896out_free:
 
 
2897	ulist_free(old_roots);
2898	ulist_free(new_roots);
2899	return ret;
2900}
2901
2902int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
 
2903{
2904	struct btrfs_fs_info *fs_info = trans->fs_info;
2905	struct btrfs_qgroup_extent_record *record;
2906	struct btrfs_delayed_ref_root *delayed_refs;
2907	struct ulist *new_roots = NULL;
2908	struct rb_node *node;
2909	u64 num_dirty_extents = 0;
2910	u64 qgroup_to_skip;
2911	int ret = 0;
2912
2913	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
2914		return 0;
2915
2916	delayed_refs = &trans->transaction->delayed_refs;
2917	qgroup_to_skip = delayed_refs->qgroup_to_skip;
2918	while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2919		record = rb_entry(node, struct btrfs_qgroup_extent_record,
2920				  node);
2921
2922		num_dirty_extents++;
2923		trace_btrfs_qgroup_account_extents(fs_info, record);
2924
2925		if (!ret && !(fs_info->qgroup_flags &
2926			      BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)) {
2927			struct btrfs_backref_walk_ctx ctx = { 0 };
2928
2929			ctx.bytenr = record->bytenr;
2930			ctx.fs_info = fs_info;
2931
2932			/*
2933			 * Old roots should be searched when inserting qgroup
2934			 * extent record.
2935			 *
2936			 * But for INCONSISTENT (NO_ACCOUNTING) -> rescan case,
2937			 * we may have some record inserted during
2938			 * NO_ACCOUNTING (thus no old_roots populated), but
2939			 * later we start rescan, which clears NO_ACCOUNTING,
2940			 * leaving some inserted records without old_roots
2941			 * populated.
2942			 *
2943			 * Those cases are rare and should not cause too much
2944			 * time spent during commit_transaction().
2945			 */
2946			if (!record->old_roots) {
2947				/* Search commit root to find old_roots */
2948				ret = btrfs_find_all_roots(&ctx, false);
2949				if (ret < 0)
2950					goto cleanup;
2951				record->old_roots = ctx.roots;
2952				ctx.roots = NULL;
2953			}
2954
 
2955			/*
2956			 * Use BTRFS_SEQ_LAST as time_seq to do special search,
2957			 * which doesn't lock tree or delayed_refs and search
2958			 * current root. It's safe inside commit_transaction().
2959			 */
2960			ctx.trans = trans;
2961			ctx.time_seq = BTRFS_SEQ_LAST;
2962			ret = btrfs_find_all_roots(&ctx, false);
2963			if (ret < 0)
2964				goto cleanup;
2965			new_roots = ctx.roots;
2966			if (qgroup_to_skip) {
2967				ulist_del(new_roots, qgroup_to_skip, 0);
2968				ulist_del(record->old_roots, qgroup_to_skip,
2969					  0);
2970			}
2971			ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2972							  record->num_bytes,
2973							  record->old_roots,
2974							  new_roots);
2975			record->old_roots = NULL;
2976			new_roots = NULL;
2977		}
2978		/* Free the reserved data space */
2979		btrfs_qgroup_free_refroot(fs_info,
2980				record->data_rsv_refroot,
2981				record->data_rsv,
2982				BTRFS_QGROUP_RSV_DATA);
2983cleanup:
2984		ulist_free(record->old_roots);
2985		ulist_free(new_roots);
2986		new_roots = NULL;
2987		rb_erase(node, &delayed_refs->dirty_extent_root);
2988		kfree(record);
2989
2990	}
2991	trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2992				       num_dirty_extents);
2993	return ret;
2994}
2995
2996/*
2997 * Writes all changed qgroups to disk.
2998 * Called by the transaction commit path and the qgroup assign ioctl.
2999 */
3000int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
 
3001{
3002	struct btrfs_fs_info *fs_info = trans->fs_info;
3003	int ret = 0;
 
 
 
 
3004
3005	/*
3006	 * In case we are called from the qgroup assign ioctl, assert that we
3007	 * are holding the qgroup_ioctl_lock, otherwise we can race with a quota
3008	 * disable operation (ioctl) and access a freed quota root.
3009	 */
3010	if (trans->transaction->state != TRANS_STATE_COMMIT_DOING)
3011		lockdep_assert_held(&fs_info->qgroup_ioctl_lock);
3012
3013	if (!fs_info->quota_root)
3014		return ret;
3015
3016	spin_lock(&fs_info->qgroup_lock);
3017	while (!list_empty(&fs_info->dirty_qgroups)) {
3018		struct btrfs_qgroup *qgroup;
3019		qgroup = list_first_entry(&fs_info->dirty_qgroups,
3020					  struct btrfs_qgroup, dirty);
3021		list_del_init(&qgroup->dirty);
3022		spin_unlock(&fs_info->qgroup_lock);
3023		ret = update_qgroup_info_item(trans, qgroup);
3024		if (ret)
3025			qgroup_mark_inconsistent(fs_info);
3026		ret = update_qgroup_limit_item(trans, qgroup);
 
3027		if (ret)
3028			qgroup_mark_inconsistent(fs_info);
 
3029		spin_lock(&fs_info->qgroup_lock);
3030	}
3031	if (btrfs_qgroup_enabled(fs_info))
3032		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
3033	else
3034		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
3035	spin_unlock(&fs_info->qgroup_lock);
3036
3037	ret = update_qgroup_status_item(trans);
3038	if (ret)
3039		qgroup_mark_inconsistent(fs_info);
3040
3041	return ret;
3042}
3043
3044int btrfs_qgroup_check_inherit(struct btrfs_fs_info *fs_info,
3045			       struct btrfs_qgroup_inherit *inherit,
3046			       size_t size)
3047{
3048	if (!btrfs_qgroup_enabled(fs_info))
3049		return 0;
3050	if (inherit->flags & ~BTRFS_QGROUP_INHERIT_FLAGS_SUPP)
3051		return -EOPNOTSUPP;
3052	if (size < sizeof(*inherit) || size > PAGE_SIZE)
3053		return -EINVAL;
3054
3055	/*
3056	 * In the past we allowed btrfs_qgroup_inherit to specify to copy
3057	 * rfer/excl numbers directly from other qgroups.  This behavior has
3058	 * been disabled in userspace for a very long time, but here we should
3059	 * also disable it in kernel, as this behavior is known to mark qgroup
3060	 * inconsistent, and a rescan would wipe out the changes anyway.
3061	 *
3062	 * Reject any btrfs_qgroup_inherit with num_ref_copies or num_excl_copies.
3063	 */
3064	if (inherit->num_ref_copies > 0 || inherit->num_excl_copies > 0)
3065		return -EINVAL;
3066
3067	if (inherit->num_qgroups > PAGE_SIZE)
3068		return -EINVAL;
3069
3070	if (size != struct_size(inherit, qgroups, inherit->num_qgroups))
3071		return -EINVAL;
3072
3073	/*
3074	 * Now check all the remaining qgroups, they should all:
3075	 *
3076	 * - Exist
3077	 * - Be higher level qgroups.
3078	 */
3079	for (int i = 0; i < inherit->num_qgroups; i++) {
3080		struct btrfs_qgroup *qgroup;
3081		u64 qgroupid = inherit->qgroups[i];
3082
3083		if (btrfs_qgroup_level(qgroupid) == 0)
3084			return -EINVAL;
3085
3086		spin_lock(&fs_info->qgroup_lock);
3087		qgroup = find_qgroup_rb(fs_info, qgroupid);
3088		if (!qgroup) {
3089			spin_unlock(&fs_info->qgroup_lock);
3090			return -ENOENT;
3091		}
3092		spin_unlock(&fs_info->qgroup_lock);
3093	}
3094	return 0;
3095}
3096
3097static int qgroup_auto_inherit(struct btrfs_fs_info *fs_info,
3098			       u64 inode_rootid,
3099			       struct btrfs_qgroup_inherit **inherit)
3100{
3101	int i = 0;
3102	u64 num_qgroups = 0;
3103	struct btrfs_qgroup *inode_qg;
3104	struct btrfs_qgroup_list *qg_list;
3105	struct btrfs_qgroup_inherit *res;
3106	size_t struct_sz;
3107	u64 *qgids;
3108
3109	if (*inherit)
3110		return -EEXIST;
3111
3112	inode_qg = find_qgroup_rb(fs_info, inode_rootid);
3113	if (!inode_qg)
3114		return -ENOENT;
3115
3116	num_qgroups = list_count_nodes(&inode_qg->groups);
3117
3118	if (!num_qgroups)
3119		return 0;
3120
3121	struct_sz = struct_size(res, qgroups, num_qgroups);
3122	if (struct_sz == SIZE_MAX)
3123		return -ERANGE;
3124
3125	res = kzalloc(struct_sz, GFP_NOFS);
3126	if (!res)
3127		return -ENOMEM;
3128	res->num_qgroups = num_qgroups;
3129	qgids = res->qgroups;
3130
3131	list_for_each_entry(qg_list, &inode_qg->groups, next_group)
3132		qgids[i] = qg_list->group->qgroupid;
3133
3134	*inherit = res;
3135	return 0;
3136}
3137
3138/*
3139 * Check if we can skip rescan when inheriting qgroups.  If @src has a single
3140 * @parent, and that @parent is owning all its bytes exclusively, we can skip
3141 * the full rescan, by just adding nodesize to the @parent's excl/rfer.
3142 *
3143 * Return <0 for fatal errors (like srcid/parentid has no qgroup).
3144 * Return 0 if a quick inherit is done.
3145 * Return >0 if a quick inherit is not possible, and a full rescan is needed.
3146 */
3147static int qgroup_snapshot_quick_inherit(struct btrfs_fs_info *fs_info,
3148					 u64 srcid, u64 parentid)
3149{
3150	struct btrfs_qgroup *src;
3151	struct btrfs_qgroup *parent;
3152	struct btrfs_qgroup_list *list;
3153	int nr_parents = 0;
3154
3155	src = find_qgroup_rb(fs_info, srcid);
3156	if (!src)
3157		return -ENOENT;
3158	parent = find_qgroup_rb(fs_info, parentid);
3159	if (!parent)
3160		return -ENOENT;
3161
3162	/*
3163	 * Source has no parent qgroup, but our new qgroup would have one.
3164	 * Qgroup numbers would become inconsistent.
3165	 */
3166	if (list_empty(&src->groups))
3167		return 1;
3168
3169	list_for_each_entry(list, &src->groups, next_group) {
3170		/* The parent is not the same, quick update is not possible. */
3171		if (list->group->qgroupid != parentid)
3172			return 1;
3173		nr_parents++;
3174		/*
3175		 * More than one parent qgroup, we can't be sure about accounting
3176		 * consistency.
3177		 */
3178		if (nr_parents > 1)
3179			return 1;
3180	}
3181
3182	/*
3183	 * The parent is not exclusively owning all its bytes.  We're not sure
3184	 * if the source has any bytes not fully owned by the parent.
3185	 */
3186	if (parent->excl != parent->rfer)
3187		return 1;
3188
3189	parent->excl += fs_info->nodesize;
3190	parent->rfer += fs_info->nodesize;
3191	return 0;
3192}
3193
3194/*
3195 * Copy the accounting information between qgroups. This is necessary
3196 * when a snapshot or a subvolume is created. Throwing an error will
3197 * cause a transaction abort so we take extra care here to only error
3198 * when a readonly fs is a reasonable outcome.
3199 */
3200int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
3201			 u64 objectid, u64 inode_rootid,
3202			 struct btrfs_qgroup_inherit *inherit)
3203{
3204	int ret = 0;
3205	int i;
3206	u64 *i_qgroups;
3207	bool committing = false;
3208	struct btrfs_fs_info *fs_info = trans->fs_info;
3209	struct btrfs_root *quota_root;
3210	struct btrfs_qgroup *srcgroup;
3211	struct btrfs_qgroup *dstgroup;
3212	struct btrfs_qgroup *prealloc;
3213	struct btrfs_qgroup_list **qlist_prealloc = NULL;
3214	bool free_inherit = false;
3215	bool need_rescan = false;
3216	u32 level_size = 0;
3217	u64 nums;
3218
3219	prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
3220	if (!prealloc)
3221		return -ENOMEM;
3222
3223	/*
3224	 * There are only two callers of this function.
3225	 *
3226	 * One in create_subvol() in the ioctl context, which needs to hold
3227	 * the qgroup_ioctl_lock.
3228	 *
3229	 * The other one in create_pending_snapshot() where no other qgroup
3230	 * code can modify the fs as they all need to either start a new trans
3231	 * or hold a trans handler, thus we don't need to hold
3232	 * qgroup_ioctl_lock.
3233	 * This would avoid long and complex lock chain and make lockdep happy.
3234	 */
3235	spin_lock(&fs_info->trans_lock);
3236	if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
3237		committing = true;
3238	spin_unlock(&fs_info->trans_lock);
3239
3240	if (!committing)
3241		mutex_lock(&fs_info->qgroup_ioctl_lock);
3242	if (!btrfs_qgroup_enabled(fs_info))
3243		goto out;
3244
3245	quota_root = fs_info->quota_root;
3246	if (!quota_root) {
3247		ret = -EINVAL;
3248		goto out;
3249	}
3250
3251	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE && !inherit) {
3252		ret = qgroup_auto_inherit(fs_info, inode_rootid, &inherit);
3253		if (ret)
3254			goto out;
3255		free_inherit = true;
3256	}
3257
3258	if (inherit) {
3259		i_qgroups = (u64 *)(inherit + 1);
3260		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
3261		       2 * inherit->num_excl_copies;
3262		for (i = 0; i < nums; ++i) {
3263			srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
3264
3265			/*
3266			 * Zero out invalid groups so we can ignore
3267			 * them later.
3268			 */
3269			if (!srcgroup ||
3270			    ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
3271				*i_qgroups = 0ULL;
3272
3273			++i_qgroups;
3274		}
3275	}
3276
3277	/*
3278	 * create a tracking group for the subvol itself
3279	 */
3280	ret = add_qgroup_item(trans, quota_root, objectid);
3281	if (ret)
3282		goto out;
3283
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3284	/*
3285	 * add qgroup to all inherited groups
3286	 */
3287	if (inherit) {
3288		i_qgroups = (u64 *)(inherit + 1);
3289		for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
3290			if (*i_qgroups == 0)
3291				continue;
3292			ret = add_qgroup_relation_item(trans, objectid,
3293						       *i_qgroups);
3294			if (ret && ret != -EEXIST)
3295				goto out;
3296			ret = add_qgroup_relation_item(trans, *i_qgroups,
3297						       objectid);
3298			if (ret && ret != -EEXIST)
3299				goto out;
3300		}
3301		ret = 0;
 
3302
3303		qlist_prealloc = kcalloc(inherit->num_qgroups,
3304					 sizeof(struct btrfs_qgroup_list *),
3305					 GFP_NOFS);
3306		if (!qlist_prealloc) {
3307			ret = -ENOMEM;
3308			goto out;
3309		}
3310		for (int i = 0; i < inherit->num_qgroups; i++) {
3311			qlist_prealloc[i] = kzalloc(sizeof(struct btrfs_qgroup_list),
3312						    GFP_NOFS);
3313			if (!qlist_prealloc[i]) {
3314				ret = -ENOMEM;
3315				goto out;
3316			}
3317		}
3318	}
3319
3320	spin_lock(&fs_info->qgroup_lock);
3321
3322	dstgroup = add_qgroup_rb(fs_info, prealloc, objectid);
3323	prealloc = NULL;
 
 
 
3324
3325	if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
3326		dstgroup->lim_flags = inherit->lim.flags;
3327		dstgroup->max_rfer = inherit->lim.max_rfer;
3328		dstgroup->max_excl = inherit->lim.max_excl;
3329		dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
3330		dstgroup->rsv_excl = inherit->lim.rsv_excl;
3331
3332		qgroup_dirty(fs_info, dstgroup);
 
 
 
 
 
 
3333	}
3334
3335	if (srcid && btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL) {
3336		srcgroup = find_qgroup_rb(fs_info, srcid);
3337		if (!srcgroup)
3338			goto unlock;
3339
3340		/*
3341		 * We call inherit after we clone the root in order to make sure
3342		 * our counts don't go crazy, so at this point the only
3343		 * difference between the two roots should be the root node.
3344		 */
3345		level_size = fs_info->nodesize;
3346		dstgroup->rfer = srcgroup->rfer;
3347		dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
3348		dstgroup->excl = level_size;
3349		dstgroup->excl_cmpr = level_size;
3350		srcgroup->excl = level_size;
3351		srcgroup->excl_cmpr = level_size;
3352
3353		/* inherit the limit info */
3354		dstgroup->lim_flags = srcgroup->lim_flags;
3355		dstgroup->max_rfer = srcgroup->max_rfer;
3356		dstgroup->max_excl = srcgroup->max_excl;
3357		dstgroup->rsv_rfer = srcgroup->rsv_rfer;
3358		dstgroup->rsv_excl = srcgroup->rsv_excl;
3359
3360		qgroup_dirty(fs_info, dstgroup);
3361		qgroup_dirty(fs_info, srcgroup);
3362
3363		/*
3364		 * If the source qgroup has parent but the new one doesn't,
3365		 * we need a full rescan.
3366		 */
3367		if (!inherit && !list_empty(&srcgroup->groups))
3368			need_rescan = true;
3369	}
3370
3371	if (!inherit)
3372		goto unlock;
3373
3374	i_qgroups = (u64 *)(inherit + 1);
3375	for (i = 0; i < inherit->num_qgroups; ++i) {
3376		if (*i_qgroups) {
3377			ret = add_relation_rb(fs_info, qlist_prealloc[i], objectid,
3378					      *i_qgroups);
3379			qlist_prealloc[i] = NULL;
3380			if (ret)
3381				goto unlock;
3382		}
3383		if (srcid) {
3384			/* Check if we can do a quick inherit. */
3385			ret = qgroup_snapshot_quick_inherit(fs_info, srcid, *i_qgroups);
3386			if (ret < 0)
3387				goto unlock;
3388			if (ret > 0)
3389				need_rescan = true;
3390			ret = 0;
3391		}
3392		++i_qgroups;
3393	}
3394
3395	for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
3396		struct btrfs_qgroup *src;
3397		struct btrfs_qgroup *dst;
3398
3399		if (!i_qgroups[0] || !i_qgroups[1])
3400			continue;
3401
3402		src = find_qgroup_rb(fs_info, i_qgroups[0]);
3403		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3404
3405		if (!src || !dst) {
3406			ret = -EINVAL;
3407			goto unlock;
3408		}
3409
3410		dst->rfer = src->rfer - level_size;
3411		dst->rfer_cmpr = src->rfer_cmpr - level_size;
3412
3413		/* Manually tweaking numbers certainly needs a rescan */
3414		need_rescan = true;
3415	}
3416	for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
3417		struct btrfs_qgroup *src;
3418		struct btrfs_qgroup *dst;
3419
3420		if (!i_qgroups[0] || !i_qgroups[1])
3421			continue;
3422
3423		src = find_qgroup_rb(fs_info, i_qgroups[0]);
3424		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3425
3426		if (!src || !dst) {
3427			ret = -EINVAL;
3428			goto unlock;
3429		}
3430
3431		dst->excl = src->excl + level_size;
3432		dst->excl_cmpr = src->excl_cmpr + level_size;
3433		need_rescan = true;
3434	}
3435
3436unlock:
3437	spin_unlock(&fs_info->qgroup_lock);
3438	if (!ret)
3439		ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup);
3440out:
3441	if (!committing)
3442		mutex_unlock(&fs_info->qgroup_ioctl_lock);
3443	if (need_rescan)
3444		qgroup_mark_inconsistent(fs_info);
3445	if (qlist_prealloc) {
3446		for (int i = 0; i < inherit->num_qgroups; i++)
3447			kfree(qlist_prealloc[i]);
3448		kfree(qlist_prealloc);
3449	}
3450	if (free_inherit)
3451		kfree(inherit);
3452	kfree(prealloc);
3453	return ret;
3454}
3455
3456static bool qgroup_check_limits(const struct btrfs_qgroup *qg, u64 num_bytes)
3457{
3458	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
3459	    qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
3460		return false;
3461
3462	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
3463	    qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
3464		return false;
3465
3466	return true;
3467}
3468
3469static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
3470			  enum btrfs_qgroup_rsv_type type)
3471{
 
3472	struct btrfs_qgroup *qgroup;
3473	struct btrfs_fs_info *fs_info = root->fs_info;
3474	u64 ref_root = root->root_key.objectid;
3475	int ret = 0;
3476	LIST_HEAD(qgroup_list);
 
3477
3478	if (!is_fstree(ref_root))
3479		return 0;
3480
3481	if (num_bytes == 0)
3482		return 0;
3483
3484	if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
3485	    capable(CAP_SYS_RESOURCE))
3486		enforce = false;
3487
3488	spin_lock(&fs_info->qgroup_lock);
3489	if (!fs_info->quota_root)
 
3490		goto out;
3491
3492	qgroup = find_qgroup_rb(fs_info, ref_root);
3493	if (!qgroup)
3494		goto out;
3495
3496	qgroup_iterator_add(&qgroup_list, qgroup);
3497	list_for_each_entry(qgroup, &qgroup_list, iterator) {
 
 
 
 
 
 
 
 
 
 
3498		struct btrfs_qgroup_list *glist;
3499
3500		if (enforce && !qgroup_check_limits(qgroup, num_bytes)) {
 
 
 
 
3501			ret = -EDQUOT;
3502			goto out;
3503		}
3504
3505		list_for_each_entry(glist, &qgroup->groups, next_group)
3506			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
 
 
 
 
 
 
 
 
 
3507	}
3508
3509	ret = 0;
3510	/*
3511	 * no limits exceeded, now record the reservation into all qgroups
3512	 */
3513	list_for_each_entry(qgroup, &qgroup_list, iterator)
3514		qgroup_rsv_add(fs_info, qgroup, num_bytes, type);
 
 
 
 
 
 
3515
3516out:
3517	qgroup_iterator_clean(&qgroup_list);
3518	spin_unlock(&fs_info->qgroup_lock);
3519	return ret;
3520}
3521
3522/*
3523 * Free @num_bytes of reserved space with @type for qgroup.  (Normally level 0
3524 * qgroup).
3525 *
3526 * Will handle all higher level qgroup too.
3527 *
3528 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
3529 * This special case is only used for META_PERTRANS type.
3530 */
3531void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
3532			       u64 ref_root, u64 num_bytes,
3533			       enum btrfs_qgroup_rsv_type type)
3534{
 
3535	struct btrfs_qgroup *qgroup;
3536	LIST_HEAD(qgroup_list);
 
 
3537
3538	if (!is_fstree(ref_root))
3539		return;
3540
3541	if (num_bytes == 0)
3542		return;
3543
3544	if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
3545		WARN(1, "%s: Invalid type to free", __func__);
3546		return;
3547	}
3548	spin_lock(&fs_info->qgroup_lock);
3549
3550	if (!fs_info->quota_root)
 
3551		goto out;
3552
3553	qgroup = find_qgroup_rb(fs_info, ref_root);
3554	if (!qgroup)
3555		goto out;
3556
3557	if (num_bytes == (u64)-1)
3558		/*
3559		 * We're freeing all pertrans rsv, get reserved value from
3560		 * level 0 qgroup as real num_bytes to free.
3561		 */
3562		num_bytes = qgroup->rsv.values[type];
 
 
 
 
 
3563
3564	qgroup_iterator_add(&qgroup_list, qgroup);
3565	list_for_each_entry(qgroup, &qgroup_list, iterator) {
3566		struct btrfs_qgroup_list *glist;
3567
3568		qgroup_rsv_release(fs_info, qgroup, num_bytes, type);
3569		list_for_each_entry(glist, &qgroup->groups, next_group) {
3570			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
3571		}
3572	}
 
3573out:
3574	qgroup_iterator_clean(&qgroup_list);
3575	spin_unlock(&fs_info->qgroup_lock);
3576}
3577
3578/*
3579 * Check if the leaf is the last leaf. Which means all node pointers
3580 * are at their last position.
3581 */
3582static bool is_last_leaf(struct btrfs_path *path)
 
3583{
3584	int i;
3585
3586	for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3587		if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3588			return false;
3589	}
3590	return true;
 
 
3591}
3592
3593/*
3594 * returns < 0 on error, 0 when more leafs are to be scanned.
3595 * returns 1 when done.
3596 */
3597static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3598			      struct btrfs_path *path)
 
3599{
3600	struct btrfs_fs_info *fs_info = trans->fs_info;
3601	struct btrfs_root *extent_root;
3602	struct btrfs_key found;
3603	struct extent_buffer *scratch_leaf = NULL;
 
 
3604	u64 num_bytes;
3605	bool done;
3606	int slot;
3607	int ret;
3608
3609	if (!btrfs_qgroup_full_accounting(fs_info))
3610		return 1;
3611
3612	mutex_lock(&fs_info->qgroup_rescan_lock);
3613	extent_root = btrfs_extent_root(fs_info,
3614				fs_info->qgroup_rescan_progress.objectid);
3615	ret = btrfs_search_slot_for_read(extent_root,
3616					 &fs_info->qgroup_rescan_progress,
3617					 path, 1, 0);
3618
3619	btrfs_debug(fs_info,
3620		"current progress key (%llu %u %llu), search_slot ret %d",
3621		fs_info->qgroup_rescan_progress.objectid,
3622		fs_info->qgroup_rescan_progress.type,
3623		fs_info->qgroup_rescan_progress.offset, ret);
3624
3625	if (ret) {
3626		/*
3627		 * The rescan is about to end, we will not be scanning any
3628		 * further blocks. We cannot unset the RESCAN flag here, because
3629		 * we want to commit the transaction if everything went well.
3630		 * To make the live accounting work in this phase, we set our
3631		 * scan progress pointer such that every real extent objectid
3632		 * will be smaller.
3633		 */
3634		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3635		btrfs_release_path(path);
3636		mutex_unlock(&fs_info->qgroup_rescan_lock);
3637		return ret;
3638	}
3639	done = is_last_leaf(path);
3640
3641	btrfs_item_key_to_cpu(path->nodes[0], &found,
3642			      btrfs_header_nritems(path->nodes[0]) - 1);
3643	fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3644
 
3645	scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3646	if (!scratch_leaf) {
3647		ret = -ENOMEM;
3648		mutex_unlock(&fs_info->qgroup_rescan_lock);
3649		goto out;
3650	}
 
 
 
3651	slot = path->slots[0];
3652	btrfs_release_path(path);
3653	mutex_unlock(&fs_info->qgroup_rescan_lock);
3654
3655	for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
3656		struct btrfs_backref_walk_ctx ctx = { 0 };
3657
3658		btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3659		if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3660		    found.type != BTRFS_METADATA_ITEM_KEY)
3661			continue;
3662		if (found.type == BTRFS_METADATA_ITEM_KEY)
3663			num_bytes = fs_info->nodesize;
3664		else
3665			num_bytes = found.offset;
3666
3667		ctx.bytenr = found.objectid;
3668		ctx.fs_info = fs_info;
3669
3670		ret = btrfs_find_all_roots(&ctx, false);
3671		if (ret < 0)
3672			goto out;
3673		/* For rescan, just pass old_roots as NULL */
3674		ret = btrfs_qgroup_account_extent(trans, found.objectid,
3675						  num_bytes, NULL, ctx.roots);
3676		if (ret < 0)
3677			goto out;
3678	}
3679out:
3680	if (scratch_leaf)
 
3681		free_extent_buffer(scratch_leaf);
 
 
3682
3683	if (done && !ret) {
3684		ret = 1;
3685		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3686	}
3687	return ret;
3688}
3689
3690static bool rescan_should_stop(struct btrfs_fs_info *fs_info)
3691{
3692	if (btrfs_fs_closing(fs_info))
3693		return true;
3694	if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
3695		return true;
3696	if (!btrfs_qgroup_enabled(fs_info))
3697		return true;
3698	if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3699		return true;
3700	return false;
3701}
3702
3703static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3704{
3705	struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3706						     qgroup_rescan_work);
3707	struct btrfs_path *path;
3708	struct btrfs_trans_handle *trans = NULL;
3709	int err = -ENOMEM;
3710	int ret = 0;
3711	bool stopped = false;
3712	bool did_leaf_rescans = false;
3713
3714	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
3715		return;
3716
3717	path = btrfs_alloc_path();
3718	if (!path)
3719		goto out;
3720	/*
3721	 * Rescan should only search for commit root, and any later difference
3722	 * should be recorded by qgroup
3723	 */
3724	path->search_commit_root = 1;
3725	path->skip_locking = 1;
3726
3727	err = 0;
3728	while (!err && !(stopped = rescan_should_stop(fs_info))) {
3729		trans = btrfs_start_transaction(fs_info->fs_root, 0);
3730		if (IS_ERR(trans)) {
3731			err = PTR_ERR(trans);
3732			break;
3733		}
3734
3735		err = qgroup_rescan_leaf(trans, path);
3736		did_leaf_rescans = true;
3737
 
3738		if (err > 0)
3739			btrfs_commit_transaction(trans);
3740		else
3741			btrfs_end_transaction(trans);
3742	}
3743
3744out:
3745	btrfs_free_path(path);
3746
3747	mutex_lock(&fs_info->qgroup_rescan_lock);
 
 
 
3748	if (err > 0 &&
3749	    fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3750		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3751	} else if (err < 0 || stopped) {
3752		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3753	}
3754	mutex_unlock(&fs_info->qgroup_rescan_lock);
3755
3756	/*
3757	 * Only update status, since the previous part has already updated the
3758	 * qgroup info, and only if we did any actual work. This also prevents
3759	 * race with a concurrent quota disable, which has already set
3760	 * fs_info->quota_root to NULL and cleared BTRFS_FS_QUOTA_ENABLED at
3761	 * btrfs_quota_disable().
3762	 */
3763	if (did_leaf_rescans) {
3764		trans = btrfs_start_transaction(fs_info->quota_root, 1);
3765		if (IS_ERR(trans)) {
3766			err = PTR_ERR(trans);
3767			trans = NULL;
3768			btrfs_err(fs_info,
3769				  "fail to start transaction for status update: %d",
3770				  err);
3771		}
3772	} else {
3773		trans = NULL;
3774	}
3775
3776	mutex_lock(&fs_info->qgroup_rescan_lock);
3777	if (!stopped ||
3778	    fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3779		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3780	if (trans) {
3781		ret = update_qgroup_status_item(trans);
3782		if (ret < 0) {
3783			err = ret;
3784			btrfs_err(fs_info, "fail to update qgroup status: %d",
3785				  err);
3786		}
3787	}
3788	fs_info->qgroup_rescan_running = false;
3789	fs_info->qgroup_flags &= ~BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN;
3790	complete_all(&fs_info->qgroup_rescan_completion);
3791	mutex_unlock(&fs_info->qgroup_rescan_lock);
3792
3793	if (!trans)
3794		return;
3795
3796	btrfs_end_transaction(trans);
3797
3798	if (stopped) {
3799		btrfs_info(fs_info, "qgroup scan paused");
3800	} else if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) {
3801		btrfs_info(fs_info, "qgroup scan cancelled");
3802	} else if (err >= 0) {
3803		btrfs_info(fs_info, "qgroup scan completed%s",
3804			err > 0 ? " (inconsistency flag cleared)" : "");
3805	} else {
3806		btrfs_err(fs_info, "qgroup scan failed with %d", err);
3807	}
 
 
 
3808}
3809
3810/*
3811 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3812 * memory required for the rescan context.
3813 */
3814static int
3815qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3816		   int init_flags)
3817{
3818	int ret = 0;
3819
3820	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) {
3821		btrfs_warn(fs_info, "qgroup rescan init failed, running in simple mode");
3822		return -EINVAL;
3823	}
3824
3825	if (!init_flags) {
3826		/* we're resuming qgroup rescan at mount time */
3827		if (!(fs_info->qgroup_flags &
3828		      BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3829			btrfs_warn(fs_info,
3830			"qgroup rescan init failed, qgroup rescan is not queued");
3831			ret = -EINVAL;
3832		} else if (!(fs_info->qgroup_flags &
3833			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3834			btrfs_warn(fs_info,
3835			"qgroup rescan init failed, qgroup is not enabled");
3836			ret = -EINVAL;
3837		}
3838
3839		if (ret)
3840			return ret;
3841	}
3842
3843	mutex_lock(&fs_info->qgroup_rescan_lock);
 
3844
3845	if (init_flags) {
3846		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3847			btrfs_warn(fs_info,
3848				   "qgroup rescan is already in progress");
3849			ret = -EINPROGRESS;
3850		} else if (!(fs_info->qgroup_flags &
3851			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3852			btrfs_warn(fs_info,
3853			"qgroup rescan init failed, qgroup is not enabled");
3854			ret = -EINVAL;
3855		} else if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
3856			/* Quota disable is in progress */
3857			ret = -EBUSY;
3858		}
3859
3860		if (ret) {
 
3861			mutex_unlock(&fs_info->qgroup_rescan_lock);
3862			return ret;
3863		}
3864		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3865	}
3866
3867	memset(&fs_info->qgroup_rescan_progress, 0,
3868		sizeof(fs_info->qgroup_rescan_progress));
3869	fs_info->qgroup_flags &= ~(BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
3870				   BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
3871	fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3872	init_completion(&fs_info->qgroup_rescan_completion);
 
 
3873	mutex_unlock(&fs_info->qgroup_rescan_lock);
3874
 
 
3875	btrfs_init_work(&fs_info->qgroup_rescan_work,
3876			btrfs_qgroup_rescan_worker, NULL);
 
 
 
 
 
 
 
 
3877	return 0;
3878}
3879
3880static void
3881qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3882{
3883	struct rb_node *n;
3884	struct btrfs_qgroup *qgroup;
3885
3886	spin_lock(&fs_info->qgroup_lock);
3887	/* clear all current qgroup tracking information */
3888	for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3889		qgroup = rb_entry(n, struct btrfs_qgroup, node);
3890		qgroup->rfer = 0;
3891		qgroup->rfer_cmpr = 0;
3892		qgroup->excl = 0;
3893		qgroup->excl_cmpr = 0;
3894		qgroup_dirty(fs_info, qgroup);
3895	}
3896	spin_unlock(&fs_info->qgroup_lock);
3897}
3898
3899int
3900btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3901{
3902	int ret = 0;
3903	struct btrfs_trans_handle *trans;
3904
3905	ret = qgroup_rescan_init(fs_info, 0, 1);
3906	if (ret)
3907		return ret;
3908
3909	/*
3910	 * We have set the rescan_progress to 0, which means no more
3911	 * delayed refs will be accounted by btrfs_qgroup_account_ref.
3912	 * However, btrfs_qgroup_account_ref may be right after its call
3913	 * to btrfs_find_all_roots, in which case it would still do the
3914	 * accounting.
3915	 * To solve this, we're committing the transaction, which will
3916	 * ensure we run all delayed refs and only after that, we are
3917	 * going to clear all tracking information for a clean start.
3918	 */
3919
3920	trans = btrfs_attach_transaction_barrier(fs_info->fs_root);
3921	if (IS_ERR(trans) && trans != ERR_PTR(-ENOENT)) {
3922		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3923		return PTR_ERR(trans);
3924	} else if (trans != ERR_PTR(-ENOENT)) {
3925		ret = btrfs_commit_transaction(trans);
3926		if (ret) {
3927			fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3928			return ret;
3929		}
3930	}
3931
3932	qgroup_rescan_zero_tracking(fs_info);
3933
3934	mutex_lock(&fs_info->qgroup_rescan_lock);
3935	fs_info->qgroup_rescan_running = true;
3936	btrfs_queue_work(fs_info->qgroup_rescan_workers,
3937			 &fs_info->qgroup_rescan_work);
3938	mutex_unlock(&fs_info->qgroup_rescan_lock);
3939
3940	return 0;
3941}
3942
3943int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3944				     bool interruptible)
3945{
3946	int running;
3947	int ret = 0;
3948
3949	mutex_lock(&fs_info->qgroup_rescan_lock);
3950	running = fs_info->qgroup_rescan_running;
 
 
3951	mutex_unlock(&fs_info->qgroup_rescan_lock);
3952
3953	if (!running)
3954		return 0;
3955
3956	if (interruptible)
3957		ret = wait_for_completion_interruptible(
3958					&fs_info->qgroup_rescan_completion);
3959	else
3960		wait_for_completion(&fs_info->qgroup_rescan_completion);
3961
3962	return ret;
3963}
3964
3965/*
3966 * this is only called from open_ctree where we're still single threaded, thus
3967 * locking is omitted here.
3968 */
3969void
3970btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3971{
3972	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3973		mutex_lock(&fs_info->qgroup_rescan_lock);
3974		fs_info->qgroup_rescan_running = true;
3975		btrfs_queue_work(fs_info->qgroup_rescan_workers,
3976				 &fs_info->qgroup_rescan_work);
3977		mutex_unlock(&fs_info->qgroup_rescan_lock);
3978	}
3979}
3980
3981#define rbtree_iterate_from_safe(node, next, start)				\
3982       for (node = start; node && ({ next = rb_next(node); 1;}); node = next)
3983
3984static int qgroup_unreserve_range(struct btrfs_inode *inode,
3985				  struct extent_changeset *reserved, u64 start,
3986				  u64 len)
3987{
3988	struct rb_node *node;
3989	struct rb_node *next;
3990	struct ulist_node *entry;
3991	int ret = 0;
3992
3993	node = reserved->range_changed.root.rb_node;
3994	if (!node)
3995		return 0;
3996	while (node) {
3997		entry = rb_entry(node, struct ulist_node, rb_node);
3998		if (entry->val < start)
3999			node = node->rb_right;
4000		else
4001			node = node->rb_left;
4002	}
4003
4004	if (entry->val > start && rb_prev(&entry->rb_node))
4005		entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node,
4006				 rb_node);
4007
4008	rbtree_iterate_from_safe(node, next, &entry->rb_node) {
4009		u64 entry_start;
4010		u64 entry_end;
4011		u64 entry_len;
4012		int clear_ret;
4013
4014		entry = rb_entry(node, struct ulist_node, rb_node);
4015		entry_start = entry->val;
4016		entry_end = entry->aux;
4017		entry_len = entry_end - entry_start + 1;
4018
4019		if (entry_start >= start + len)
4020			break;
4021		if (entry_start + entry_len <= start)
4022			continue;
4023		/*
4024		 * Now the entry is in [start, start + len), revert the
4025		 * EXTENT_QGROUP_RESERVED bit.
4026		 */
4027		clear_ret = clear_extent_bits(&inode->io_tree, entry_start,
4028					      entry_end, EXTENT_QGROUP_RESERVED);
4029		if (!ret && clear_ret < 0)
4030			ret = clear_ret;
4031
4032		ulist_del(&reserved->range_changed, entry->val, entry->aux);
4033		if (likely(reserved->bytes_changed >= entry_len)) {
4034			reserved->bytes_changed -= entry_len;
4035		} else {
4036			WARN_ON(1);
4037			reserved->bytes_changed = 0;
4038		}
4039	}
4040
4041	return ret;
4042}
4043
4044/*
4045 * Try to free some space for qgroup.
4046 *
4047 * For qgroup, there are only 3 ways to free qgroup space:
4048 * - Flush nodatacow write
4049 *   Any nodatacow write will free its reserved data space at run_delalloc_range().
4050 *   In theory, we should only flush nodatacow inodes, but it's not yet
4051 *   possible, so we need to flush the whole root.
4052 *
4053 * - Wait for ordered extents
4054 *   When ordered extents are finished, their reserved metadata is finally
4055 *   converted to per_trans status, which can be freed by later commit
4056 *   transaction.
4057 *
4058 * - Commit transaction
4059 *   This would free the meta_per_trans space.
4060 *   In theory this shouldn't provide much space, but any more qgroup space
4061 *   is needed.
4062 */
4063static int try_flush_qgroup(struct btrfs_root *root)
4064{
4065	struct btrfs_trans_handle *trans;
 
 
 
4066	int ret;
4067
4068	/* Can't hold an open transaction or we run the risk of deadlocking. */
4069	ASSERT(current->journal_info == NULL);
4070	if (WARN_ON(current->journal_info))
4071		return 0;
4072
4073	/*
4074	 * We don't want to run flush again and again, so if there is a running
4075	 * one, we won't try to start a new flush, but exit directly.
4076	 */
4077	if (test_and_set_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)) {
4078		wait_event(root->qgroup_flush_wait,
4079			!test_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state));
4080		return 0;
4081	}
4082
4083	ret = btrfs_start_delalloc_snapshot(root, true);
 
 
 
 
 
 
 
4084	if (ret < 0)
4085		goto out;
4086	btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
4087
4088	trans = btrfs_attach_transaction_barrier(root);
4089	if (IS_ERR(trans)) {
4090		ret = PTR_ERR(trans);
4091		if (ret == -ENOENT)
4092			ret = 0;
4093		goto out;
4094	}
4095
4096	ret = btrfs_commit_transaction(trans);
4097out:
4098	clear_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state);
4099	wake_up(&root->qgroup_flush_wait);
4100	return ret;
4101}
4102
4103static int qgroup_reserve_data(struct btrfs_inode *inode,
4104			struct extent_changeset **reserved_ret, u64 start,
4105			u64 len)
4106{
4107	struct btrfs_root *root = inode->root;
4108	struct extent_changeset *reserved;
4109	bool new_reserved = false;
4110	u64 orig_reserved;
4111	u64 to_reserve;
4112	int ret;
4113
4114	if (btrfs_qgroup_mode(root->fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4115	    !is_fstree(root->root_key.objectid) || len == 0)
4116		return 0;
4117
4118	/* @reserved parameter is mandatory for qgroup */
4119	if (WARN_ON(!reserved_ret))
4120		return -EINVAL;
4121	if (!*reserved_ret) {
4122		new_reserved = true;
4123		*reserved_ret = extent_changeset_alloc();
4124		if (!*reserved_ret)
4125			return -ENOMEM;
4126	}
4127	reserved = *reserved_ret;
4128	/* Record already reserved space */
4129	orig_reserved = reserved->bytes_changed;
4130	ret = set_record_extent_bits(&inode->io_tree, start,
4131			start + len -1, EXTENT_QGROUP_RESERVED, reserved);
4132
4133	/* Newly reserved space */
4134	to_reserve = reserved->bytes_changed - orig_reserved;
4135	trace_btrfs_qgroup_reserve_data(&inode->vfs_inode, start, len,
4136					to_reserve, QGROUP_RESERVE);
4137	if (ret < 0)
4138		goto out;
4139	ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
4140	if (ret < 0)
4141		goto cleanup;
4142
 
4143	return ret;
4144
4145cleanup:
4146	qgroup_unreserve_range(inode, reserved, start, len);
4147out:
4148	if (new_reserved) {
4149		extent_changeset_free(reserved);
4150		*reserved_ret = NULL;
4151	}
4152	return ret;
4153}
4154
4155/*
4156 * Reserve qgroup space for range [start, start + len).
4157 *
4158 * This function will either reserve space from related qgroups or do nothing
4159 * if the range is already reserved.
4160 *
4161 * Return 0 for successful reservation
4162 * Return <0 for error (including -EQUOT)
4163 *
4164 * NOTE: This function may sleep for memory allocation, dirty page flushing and
4165 *	 commit transaction. So caller should not hold any dirty page locked.
4166 */
4167int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
4168			struct extent_changeset **reserved_ret, u64 start,
4169			u64 len)
4170{
4171	int ret;
4172
4173	ret = qgroup_reserve_data(inode, reserved_ret, start, len);
4174	if (ret <= 0 && ret != -EDQUOT)
4175		return ret;
4176
4177	ret = try_flush_qgroup(inode->root);
4178	if (ret < 0)
4179		return ret;
4180	return qgroup_reserve_data(inode, reserved_ret, start, len);
4181}
4182
4183/* Free ranges specified by @reserved, normally in error path */
4184static int qgroup_free_reserved_data(struct btrfs_inode *inode,
4185				     struct extent_changeset *reserved,
4186				     u64 start, u64 len, u64 *freed_ret)
4187{
4188	struct btrfs_root *root = inode->root;
4189	struct ulist_node *unode;
4190	struct ulist_iterator uiter;
4191	struct extent_changeset changeset;
4192	u64 freed = 0;
4193	int ret;
4194
4195	extent_changeset_init(&changeset);
4196	len = round_up(start + len, root->fs_info->sectorsize);
4197	start = round_down(start, root->fs_info->sectorsize);
4198
4199	ULIST_ITER_INIT(&uiter);
4200	while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
4201		u64 range_start = unode->val;
4202		/* unode->aux is the inclusive end */
4203		u64 range_len = unode->aux - range_start + 1;
4204		u64 free_start;
4205		u64 free_len;
4206
4207		extent_changeset_release(&changeset);
4208
4209		/* Only free range in range [start, start + len) */
4210		if (range_start >= start + len ||
4211		    range_start + range_len <= start)
4212			continue;
4213		free_start = max(range_start, start);
4214		free_len = min(start + len, range_start + range_len) -
4215			   free_start;
4216		/*
4217		 * TODO: To also modify reserved->ranges_reserved to reflect
4218		 * the modification.
4219		 *
4220		 * However as long as we free qgroup reserved according to
4221		 * EXTENT_QGROUP_RESERVED, we won't double free.
4222		 * So not need to rush.
4223		 */
4224		ret = clear_record_extent_bits(&inode->io_tree, free_start,
4225				free_start + free_len - 1,
4226				EXTENT_QGROUP_RESERVED, &changeset);
4227		if (ret < 0)
4228			goto out;
4229		freed += changeset.bytes_changed;
4230	}
4231	btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
4232				  BTRFS_QGROUP_RSV_DATA);
4233	if (freed_ret)
4234		*freed_ret = freed;
4235	ret = 0;
4236out:
4237	extent_changeset_release(&changeset);
4238	return ret;
4239}
4240
4241static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
4242			struct extent_changeset *reserved, u64 start, u64 len,
4243			u64 *released, int free)
4244{
4245	struct extent_changeset changeset;
4246	int trace_op = QGROUP_RELEASE;
4247	int ret;
4248
4249	if (btrfs_qgroup_mode(inode->root->fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
4250		extent_changeset_init(&changeset);
4251		return clear_record_extent_bits(&inode->io_tree, start,
4252						start + len - 1,
4253						EXTENT_QGROUP_RESERVED, &changeset);
4254	}
4255
4256	/* In release case, we shouldn't have @reserved */
4257	WARN_ON(!free && reserved);
4258	if (free && reserved)
4259		return qgroup_free_reserved_data(inode, reserved, start, len, released);
4260	extent_changeset_init(&changeset);
4261	ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1,
4262				       EXTENT_QGROUP_RESERVED, &changeset);
4263	if (ret < 0)
4264		goto out;
4265
4266	if (free)
 
4267		trace_op = QGROUP_FREE;
4268	trace_btrfs_qgroup_release_data(&inode->vfs_inode, start, len,
 
4269					changeset.bytes_changed, trace_op);
4270	if (free)
4271		btrfs_qgroup_free_refroot(inode->root->fs_info,
4272				inode->root->root_key.objectid,
4273				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4274	if (released)
4275		*released = changeset.bytes_changed;
4276out:
4277	extent_changeset_release(&changeset);
4278	return ret;
4279}
4280
4281/*
4282 * Free a reserved space range from io_tree and related qgroups
4283 *
4284 * Should be called when a range of pages get invalidated before reaching disk.
4285 * Or for error cleanup case.
4286 * if @reserved is given, only reserved range in [@start, @start + @len) will
4287 * be freed.
4288 *
4289 * For data written to disk, use btrfs_qgroup_release_data().
4290 *
4291 * NOTE: This function may sleep for memory allocation.
4292 */
4293int btrfs_qgroup_free_data(struct btrfs_inode *inode,
4294			   struct extent_changeset *reserved,
4295			   u64 start, u64 len, u64 *freed)
4296{
4297	return __btrfs_qgroup_release_data(inode, reserved, start, len, freed, 1);
4298}
4299
4300/*
4301 * Release a reserved space range from io_tree only.
4302 *
4303 * Should be called when a range of pages get written to disk and corresponding
4304 * FILE_EXTENT is inserted into corresponding root.
4305 *
4306 * Since new qgroup accounting framework will only update qgroup numbers at
4307 * commit_transaction() time, its reserved space shouldn't be freed from
4308 * related qgroups.
4309 *
4310 * But we should release the range from io_tree, to allow further write to be
4311 * COWed.
4312 *
4313 * NOTE: This function may sleep for memory allocation.
4314 */
4315int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released)
4316{
4317	return __btrfs_qgroup_release_data(inode, NULL, start, len, released, 0);
4318}
4319
4320static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4321			      enum btrfs_qgroup_rsv_type type)
4322{
4323	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4324	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
4325		return;
4326	if (num_bytes == 0)
4327		return;
4328
4329	spin_lock(&root->qgroup_meta_rsv_lock);
4330	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
4331		root->qgroup_meta_rsv_prealloc += num_bytes;
4332	else
4333		root->qgroup_meta_rsv_pertrans += num_bytes;
4334	spin_unlock(&root->qgroup_meta_rsv_lock);
4335}
4336
4337static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4338			     enum btrfs_qgroup_rsv_type type)
4339{
4340	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4341	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
4342		return 0;
4343	if (num_bytes == 0)
4344		return 0;
4345
4346	spin_lock(&root->qgroup_meta_rsv_lock);
4347	if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
4348		num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
4349				  num_bytes);
4350		root->qgroup_meta_rsv_prealloc -= num_bytes;
4351	} else {
4352		num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
4353				  num_bytes);
4354		root->qgroup_meta_rsv_pertrans -= num_bytes;
4355	}
4356	spin_unlock(&root->qgroup_meta_rsv_lock);
4357	return num_bytes;
4358}
4359
4360int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4361			      enum btrfs_qgroup_rsv_type type, bool enforce)
4362{
4363	struct btrfs_fs_info *fs_info = root->fs_info;
4364	int ret;
4365
4366	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4367	    !is_fstree(root->root_key.objectid) || num_bytes == 0)
4368		return 0;
4369
4370	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4371	trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
4372	ret = qgroup_reserve(root, num_bytes, enforce, type);
4373	if (ret < 0)
4374		return ret;
4375	/*
4376	 * Record what we have reserved into root.
4377	 *
4378	 * To avoid quota disabled->enabled underflow.
4379	 * In that case, we may try to free space we haven't reserved
4380	 * (since quota was disabled), so record what we reserved into root.
4381	 * And ensure later release won't underflow this number.
4382	 */
4383	add_root_meta_rsv(root, num_bytes, type);
4384	return ret;
4385}
4386
4387int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4388				enum btrfs_qgroup_rsv_type type, bool enforce,
4389				bool noflush)
4390{
4391	int ret;
4392
4393	ret = btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4394	if ((ret <= 0 && ret != -EDQUOT) || noflush)
4395		return ret;
4396
4397	ret = try_flush_qgroup(root);
4398	if (ret < 0)
4399		return ret;
4400	return btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4401}
4402
4403/*
4404 * Per-transaction meta reservation should be all freed at transaction commit
4405 * time
4406 */
4407void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
4408{
4409	struct btrfs_fs_info *fs_info = root->fs_info;
4410
4411	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4412	    !is_fstree(root->root_key.objectid))
4413		return;
4414
4415	/* TODO: Update trace point to handle such free */
4416	trace_qgroup_meta_free_all_pertrans(root);
4417	/* Special value -1 means to free all reserved space */
4418	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
4419				  BTRFS_QGROUP_RSV_META_PERTRANS);
4420}
4421
4422void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
4423			      enum btrfs_qgroup_rsv_type type)
4424{
4425	struct btrfs_fs_info *fs_info = root->fs_info;
4426
4427	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4428	    !is_fstree(root->root_key.objectid))
4429		return;
4430
4431	/*
4432	 * reservation for META_PREALLOC can happen before quota is enabled,
4433	 * which can lead to underflow.
4434	 * Here ensure we will only free what we really have reserved.
4435	 */
4436	num_bytes = sub_root_meta_rsv(root, num_bytes, type);
4437	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4438	trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
4439	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
4440				  num_bytes, type);
4441}
4442
4443static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
4444				int num_bytes)
4445{
4446	struct btrfs_qgroup *qgroup;
4447	LIST_HEAD(qgroup_list);
4448
4449	if (num_bytes == 0)
4450		return;
4451	if (!fs_info->quota_root)
4452		return;
4453
4454	spin_lock(&fs_info->qgroup_lock);
4455	qgroup = find_qgroup_rb(fs_info, ref_root);
4456	if (!qgroup)
4457		goto out;
4458
4459	qgroup_iterator_add(&qgroup_list, qgroup);
4460	list_for_each_entry(qgroup, &qgroup_list, iterator) {
4461		struct btrfs_qgroup_list *glist;
4462
4463		qgroup_rsv_release(fs_info, qgroup, num_bytes,
4464				BTRFS_QGROUP_RSV_META_PREALLOC);
4465		if (!sb_rdonly(fs_info->sb))
4466			qgroup_rsv_add(fs_info, qgroup, num_bytes,
4467				       BTRFS_QGROUP_RSV_META_PERTRANS);
4468
4469		list_for_each_entry(glist, &qgroup->groups, next_group)
4470			qgroup_iterator_add(&qgroup_list, glist->group);
4471	}
4472out:
4473	qgroup_iterator_clean(&qgroup_list);
4474	spin_unlock(&fs_info->qgroup_lock);
4475}
4476
4477/*
4478 * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS.
4479 *
4480 * This is called when preallocated meta reservation needs to be used.
4481 * Normally after btrfs_join_transaction() call.
4482 */
4483void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
4484{
4485	struct btrfs_fs_info *fs_info = root->fs_info;
4486
4487	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4488	    !is_fstree(root->root_key.objectid))
4489		return;
4490	/* Same as btrfs_qgroup_free_meta_prealloc() */
4491	num_bytes = sub_root_meta_rsv(root, num_bytes,
4492				      BTRFS_QGROUP_RSV_META_PREALLOC);
4493	trace_qgroup_meta_convert(root, num_bytes);
4494	qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
4495	if (!sb_rdonly(fs_info->sb))
4496		add_root_meta_rsv(root, num_bytes, BTRFS_QGROUP_RSV_META_PERTRANS);
4497}
4498
4499/*
4500 * Check qgroup reserved space leaking, normally at destroy inode
4501 * time
4502 */
4503void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode)
4504{
4505	struct extent_changeset changeset;
4506	struct ulist_node *unode;
4507	struct ulist_iterator iter;
4508	int ret;
4509
4510	extent_changeset_init(&changeset);
4511	ret = clear_record_extent_bits(&inode->io_tree, 0, (u64)-1,
4512			EXTENT_QGROUP_RESERVED, &changeset);
 
 
 
 
4513
4514	WARN_ON(ret < 0);
4515	if (WARN_ON(changeset.bytes_changed)) {
4516		ULIST_ITER_INIT(&iter);
4517		while ((unode = ulist_next(&changeset.range_changed, &iter))) {
4518			btrfs_warn(inode->root->fs_info,
4519		"leaking qgroup reserved space, ino: %llu, start: %llu, end: %llu",
4520				btrfs_ino(inode), unode->val, unode->aux);
4521		}
4522		btrfs_qgroup_free_refroot(inode->root->fs_info,
4523				inode->root->root_key.objectid,
4524				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4525
4526	}
4527	extent_changeset_release(&changeset);
4528}
4529
4530void btrfs_qgroup_init_swapped_blocks(
4531	struct btrfs_qgroup_swapped_blocks *swapped_blocks)
4532{
4533	int i;
4534
4535	spin_lock_init(&swapped_blocks->lock);
4536	for (i = 0; i < BTRFS_MAX_LEVEL; i++)
4537		swapped_blocks->blocks[i] = RB_ROOT;
4538	swapped_blocks->swapped = false;
4539}
4540
4541/*
4542 * Delete all swapped blocks record of @root.
4543 * Every record here means we skipped a full subtree scan for qgroup.
4544 *
4545 * Gets called when committing one transaction.
4546 */
4547void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root)
4548{
4549	struct btrfs_qgroup_swapped_blocks *swapped_blocks;
4550	int i;
4551
4552	swapped_blocks = &root->swapped_blocks;
4553
4554	spin_lock(&swapped_blocks->lock);
4555	if (!swapped_blocks->swapped)
4556		goto out;
4557	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4558		struct rb_root *cur_root = &swapped_blocks->blocks[i];
4559		struct btrfs_qgroup_swapped_block *entry;
4560		struct btrfs_qgroup_swapped_block *next;
4561
4562		rbtree_postorder_for_each_entry_safe(entry, next, cur_root,
4563						     node)
4564			kfree(entry);
4565		swapped_blocks->blocks[i] = RB_ROOT;
4566	}
4567	swapped_blocks->swapped = false;
4568out:
4569	spin_unlock(&swapped_blocks->lock);
4570}
4571
4572/*
4573 * Add subtree roots record into @subvol_root.
4574 *
4575 * @subvol_root:	tree root of the subvolume tree get swapped
4576 * @bg:			block group under balance
4577 * @subvol_parent/slot:	pointer to the subtree root in subvolume tree
4578 * @reloc_parent/slot:	pointer to the subtree root in reloc tree
4579 *			BOTH POINTERS ARE BEFORE TREE SWAP
4580 * @last_snapshot:	last snapshot generation of the subvolume tree
4581 */
4582int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
4583		struct btrfs_root *subvol_root,
4584		struct btrfs_block_group *bg,
4585		struct extent_buffer *subvol_parent, int subvol_slot,
4586		struct extent_buffer *reloc_parent, int reloc_slot,
4587		u64 last_snapshot)
4588{
4589	struct btrfs_fs_info *fs_info = subvol_root->fs_info;
4590	struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks;
4591	struct btrfs_qgroup_swapped_block *block;
4592	struct rb_node **cur;
4593	struct rb_node *parent = NULL;
4594	int level = btrfs_header_level(subvol_parent) - 1;
4595	int ret = 0;
4596
4597	if (!btrfs_qgroup_full_accounting(fs_info))
4598		return 0;
4599
4600	if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) >
4601	    btrfs_node_ptr_generation(reloc_parent, reloc_slot)) {
4602		btrfs_err_rl(fs_info,
4603		"%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu",
4604			__func__,
4605			btrfs_node_ptr_generation(subvol_parent, subvol_slot),
4606			btrfs_node_ptr_generation(reloc_parent, reloc_slot));
4607		return -EUCLEAN;
4608	}
4609
4610	block = kmalloc(sizeof(*block), GFP_NOFS);
4611	if (!block) {
4612		ret = -ENOMEM;
4613		goto out;
4614	}
4615
4616	/*
4617	 * @reloc_parent/slot is still before swap, while @block is going to
4618	 * record the bytenr after swap, so we do the swap here.
4619	 */
4620	block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot);
4621	block->subvol_generation = btrfs_node_ptr_generation(reloc_parent,
4622							     reloc_slot);
4623	block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot);
4624	block->reloc_generation = btrfs_node_ptr_generation(subvol_parent,
4625							    subvol_slot);
4626	block->last_snapshot = last_snapshot;
4627	block->level = level;
4628
4629	/*
4630	 * If we have bg == NULL, we're called from btrfs_recover_relocation(),
4631	 * no one else can modify tree blocks thus we qgroup will not change
4632	 * no matter the value of trace_leaf.
4633	 */
4634	if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA)
4635		block->trace_leaf = true;
4636	else
4637		block->trace_leaf = false;
4638	btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot);
4639
4640	/* Insert @block into @blocks */
4641	spin_lock(&blocks->lock);
4642	cur = &blocks->blocks[level].rb_node;
4643	while (*cur) {
4644		struct btrfs_qgroup_swapped_block *entry;
4645
4646		parent = *cur;
4647		entry = rb_entry(parent, struct btrfs_qgroup_swapped_block,
4648				 node);
4649
4650		if (entry->subvol_bytenr < block->subvol_bytenr) {
4651			cur = &(*cur)->rb_left;
4652		} else if (entry->subvol_bytenr > block->subvol_bytenr) {
4653			cur = &(*cur)->rb_right;
4654		} else {
4655			if (entry->subvol_generation !=
4656					block->subvol_generation ||
4657			    entry->reloc_bytenr != block->reloc_bytenr ||
4658			    entry->reloc_generation !=
4659					block->reloc_generation) {
4660				/*
4661				 * Duplicated but mismatch entry found.
4662				 * Shouldn't happen.
4663				 *
4664				 * Marking qgroup inconsistent should be enough
4665				 * for end users.
4666				 */
4667				WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4668				ret = -EEXIST;
4669			}
4670			kfree(block);
4671			goto out_unlock;
4672		}
4673	}
4674	rb_link_node(&block->node, parent, cur);
4675	rb_insert_color(&block->node, &blocks->blocks[level]);
4676	blocks->swapped = true;
4677out_unlock:
4678	spin_unlock(&blocks->lock);
4679out:
4680	if (ret < 0)
4681		qgroup_mark_inconsistent(fs_info);
4682	return ret;
4683}
4684
4685/*
4686 * Check if the tree block is a subtree root, and if so do the needed
4687 * delayed subtree trace for qgroup.
4688 *
4689 * This is called during btrfs_cow_block().
4690 */
4691int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
4692					 struct btrfs_root *root,
4693					 struct extent_buffer *subvol_eb)
4694{
4695	struct btrfs_fs_info *fs_info = root->fs_info;
4696	struct btrfs_tree_parent_check check = { 0 };
4697	struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks;
4698	struct btrfs_qgroup_swapped_block *block;
4699	struct extent_buffer *reloc_eb = NULL;
4700	struct rb_node *node;
4701	bool found = false;
4702	bool swapped = false;
4703	int level = btrfs_header_level(subvol_eb);
4704	int ret = 0;
4705	int i;
4706
4707	if (!btrfs_qgroup_full_accounting(fs_info))
4708		return 0;
4709	if (!is_fstree(root->root_key.objectid) || !root->reloc_root)
4710		return 0;
4711
4712	spin_lock(&blocks->lock);
4713	if (!blocks->swapped) {
4714		spin_unlock(&blocks->lock);
4715		return 0;
4716	}
4717	node = blocks->blocks[level].rb_node;
4718
4719	while (node) {
4720		block = rb_entry(node, struct btrfs_qgroup_swapped_block, node);
4721		if (block->subvol_bytenr < subvol_eb->start) {
4722			node = node->rb_left;
4723		} else if (block->subvol_bytenr > subvol_eb->start) {
4724			node = node->rb_right;
4725		} else {
4726			found = true;
4727			break;
4728		}
4729	}
4730	if (!found) {
4731		spin_unlock(&blocks->lock);
4732		goto out;
4733	}
4734	/* Found one, remove it from @blocks first and update blocks->swapped */
4735	rb_erase(&block->node, &blocks->blocks[level]);
4736	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4737		if (RB_EMPTY_ROOT(&blocks->blocks[i])) {
4738			swapped = true;
4739			break;
4740		}
4741	}
4742	blocks->swapped = swapped;
4743	spin_unlock(&blocks->lock);
4744
4745	check.level = block->level;
4746	check.transid = block->reloc_generation;
4747	check.has_first_key = true;
4748	memcpy(&check.first_key, &block->first_key, sizeof(check.first_key));
4749
4750	/* Read out reloc subtree root */
4751	reloc_eb = read_tree_block(fs_info, block->reloc_bytenr, &check);
4752	if (IS_ERR(reloc_eb)) {
4753		ret = PTR_ERR(reloc_eb);
4754		reloc_eb = NULL;
4755		goto free_out;
4756	}
4757	if (!extent_buffer_uptodate(reloc_eb)) {
4758		ret = -EIO;
4759		goto free_out;
4760	}
4761
4762	ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb,
4763			block->last_snapshot, block->trace_leaf);
4764free_out:
4765	kfree(block);
4766	free_extent_buffer(reloc_eb);
4767out:
4768	if (ret < 0) {
4769		btrfs_err_rl(fs_info,
4770			     "failed to account subtree at bytenr %llu: %d",
4771			     subvol_eb->start, ret);
4772		qgroup_mark_inconsistent(fs_info);
4773	}
4774	return ret;
4775}
4776
4777void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans)
4778{
4779	struct btrfs_qgroup_extent_record *entry;
4780	struct btrfs_qgroup_extent_record *next;
4781	struct rb_root *root;
4782
4783	root = &trans->delayed_refs.dirty_extent_root;
4784	rbtree_postorder_for_each_entry_safe(entry, next, root, node) {
4785		ulist_free(entry->old_roots);
4786		kfree(entry);
4787	}
4788	*root = RB_ROOT;
4789}
4790
4791void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes)
4792{
4793	if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4794		return;
4795
4796	if (!is_fstree(root))
4797		return;
4798
4799	btrfs_qgroup_free_refroot(fs_info, root, rsv_bytes, BTRFS_QGROUP_RSV_DATA);
4800}
4801
4802int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
4803			      struct btrfs_squota_delta *delta)
4804{
4805	int ret;
4806	struct btrfs_qgroup *qgroup;
4807	struct btrfs_qgroup *qg;
4808	LIST_HEAD(qgroup_list);
4809	u64 root = delta->root;
4810	u64 num_bytes = delta->num_bytes;
4811	const int sign = (delta->is_inc ? 1 : -1);
4812
4813	if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4814		return 0;
4815
4816	if (!is_fstree(root))
4817		return 0;
4818
4819	/* If the extent predates enabling quotas, don't count it. */
4820	if (delta->generation < fs_info->qgroup_enable_gen)
4821		return 0;
4822
4823	spin_lock(&fs_info->qgroup_lock);
4824	qgroup = find_qgroup_rb(fs_info, root);
4825	if (!qgroup) {
4826		ret = -ENOENT;
4827		goto out;
4828	}
4829
4830	ret = 0;
4831	qgroup_iterator_add(&qgroup_list, qgroup);
4832	list_for_each_entry(qg, &qgroup_list, iterator) {
4833		struct btrfs_qgroup_list *glist;
4834
4835		qg->excl += num_bytes * sign;
4836		qg->rfer += num_bytes * sign;
4837		qgroup_dirty(fs_info, qg);
4838
4839		list_for_each_entry(glist, &qg->groups, next_group)
4840			qgroup_iterator_add(&qgroup_list, glist->group);
4841	}
4842	qgroup_iterator_clean(&qgroup_list);
4843
4844out:
4845	spin_unlock(&fs_info->qgroup_lock);
4846	return ret;
4847}