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v5.4
   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/sizes.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
  26/* TODO XXX FIXME
  27 *  - subvol delete -> delete when ref goes to 0? delete limits also?
  28 *  - reorganize keys
  29 *  - compressed
  30 *  - sync
  31 *  - copy also limits on subvol creation
  32 *  - limit
  33 *  - caches for ulists
  34 *  - performance benchmarks
  35 *  - check all ioctl parameters
  36 */
 
 
 
 
 
 
 
  37
  38/*
  39 * Helpers to access qgroup reservation
  40 *
  41 * Callers should ensure the lock context and type are valid
  42 */
  43
  44static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup)
  45{
  46	u64 ret = 0;
  47	int i;
  48
  49	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
  50		ret += qgroup->rsv.values[i];
  51
  52	return ret;
  53}
  54
  55#ifdef CONFIG_BTRFS_DEBUG
  56static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type)
  57{
  58	if (type == BTRFS_QGROUP_RSV_DATA)
  59		return "data";
  60	if (type == BTRFS_QGROUP_RSV_META_PERTRANS)
  61		return "meta_pertrans";
  62	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
  63		return "meta_prealloc";
  64	return NULL;
  65}
  66#endif
  67
  68static void qgroup_rsv_add(struct btrfs_fs_info *fs_info,
  69			   struct btrfs_qgroup *qgroup, u64 num_bytes,
  70			   enum btrfs_qgroup_rsv_type type)
  71{
  72	trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type);
  73	qgroup->rsv.values[type] += num_bytes;
  74}
  75
  76static void qgroup_rsv_release(struct btrfs_fs_info *fs_info,
  77			       struct btrfs_qgroup *qgroup, u64 num_bytes,
  78			       enum btrfs_qgroup_rsv_type type)
  79{
  80	trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type);
  81	if (qgroup->rsv.values[type] >= num_bytes) {
  82		qgroup->rsv.values[type] -= num_bytes;
  83		return;
  84	}
  85#ifdef CONFIG_BTRFS_DEBUG
  86	WARN_RATELIMIT(1,
  87		"qgroup %llu %s reserved space underflow, have %llu to free %llu",
  88		qgroup->qgroupid, qgroup_rsv_type_str(type),
  89		qgroup->rsv.values[type], num_bytes);
  90#endif
  91	qgroup->rsv.values[type] = 0;
  92}
  93
  94static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info,
  95				     struct btrfs_qgroup *dest,
  96				     struct btrfs_qgroup *src)
  97{
  98	int i;
  99
 100	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 101		qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i);
 102}
 103
 104static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info,
 105					 struct btrfs_qgroup *dest,
 106					  struct btrfs_qgroup *src)
 107{
 108	int i;
 109
 110	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 111		qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i);
 112}
 113
 114static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
 115					   int mod)
 116{
 117	if (qg->old_refcnt < seq)
 118		qg->old_refcnt = seq;
 119	qg->old_refcnt += mod;
 120}
 121
 122static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
 123					   int mod)
 124{
 125	if (qg->new_refcnt < seq)
 126		qg->new_refcnt = seq;
 127	qg->new_refcnt += mod;
 128}
 129
 130static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
 131{
 132	if (qg->old_refcnt < seq)
 133		return 0;
 134	return qg->old_refcnt - seq;
 135}
 136
 137static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
 138{
 139	if (qg->new_refcnt < seq)
 140		return 0;
 141	return qg->new_refcnt - seq;
 142}
 143
 144/*
 145 * glue structure to represent the relations between qgroups.
 146 */
 147struct btrfs_qgroup_list {
 148	struct list_head next_group;
 149	struct list_head next_member;
 150	struct btrfs_qgroup *group;
 151	struct btrfs_qgroup *member;
 152};
 153
 154static inline u64 qgroup_to_aux(struct btrfs_qgroup *qg)
 155{
 156	return (u64)(uintptr_t)qg;
 157}
 158
 159static inline struct btrfs_qgroup* unode_aux_to_qgroup(struct ulist_node *n)
 160{
 161	return (struct btrfs_qgroup *)(uintptr_t)n->aux;
 162}
 163
 164static int
 165qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
 166		   int init_flags);
 167static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 168
 169/* must be called with qgroup_ioctl_lock held */
 170static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
 171					   u64 qgroupid)
 172{
 173	struct rb_node *n = fs_info->qgroup_tree.rb_node;
 174	struct btrfs_qgroup *qgroup;
 175
 176	while (n) {
 177		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 178		if (qgroup->qgroupid < qgroupid)
 179			n = n->rb_left;
 180		else if (qgroup->qgroupid > qgroupid)
 181			n = n->rb_right;
 182		else
 183			return qgroup;
 184	}
 185	return NULL;
 186}
 187
 188/* must be called with qgroup_lock held */
 
 
 
 
 
 
 
 189static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
 
 190					  u64 qgroupid)
 191{
 192	struct rb_node **p = &fs_info->qgroup_tree.rb_node;
 193	struct rb_node *parent = NULL;
 194	struct btrfs_qgroup *qgroup;
 195
 
 
 
 196	while (*p) {
 197		parent = *p;
 198		qgroup = rb_entry(parent, struct btrfs_qgroup, node);
 199
 200		if (qgroup->qgroupid < qgroupid)
 201			p = &(*p)->rb_left;
 202		else if (qgroup->qgroupid > qgroupid)
 203			p = &(*p)->rb_right;
 204		else
 
 205			return qgroup;
 
 206	}
 207
 208	qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
 209	if (!qgroup)
 210		return ERR_PTR(-ENOMEM);
 211
 212	qgroup->qgroupid = qgroupid;
 213	INIT_LIST_HEAD(&qgroup->groups);
 214	INIT_LIST_HEAD(&qgroup->members);
 215	INIT_LIST_HEAD(&qgroup->dirty);
 
 
 216
 217	rb_link_node(&qgroup->node, parent, p);
 218	rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
 219
 220	return qgroup;
 221}
 222
 223static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
 
 224{
 225	struct btrfs_qgroup_list *list;
 226
 227	list_del(&qgroup->dirty);
 228	while (!list_empty(&qgroup->groups)) {
 229		list = list_first_entry(&qgroup->groups,
 230					struct btrfs_qgroup_list, next_group);
 231		list_del(&list->next_group);
 232		list_del(&list->next_member);
 233		kfree(list);
 234	}
 235
 236	while (!list_empty(&qgroup->members)) {
 237		list = list_first_entry(&qgroup->members,
 238					struct btrfs_qgroup_list, next_member);
 239		list_del(&list->next_group);
 240		list_del(&list->next_member);
 241		kfree(list);
 242	}
 243	kfree(qgroup);
 244}
 245
 246/* must be called with qgroup_lock held */
 247static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
 248{
 249	struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
 250
 251	if (!qgroup)
 252		return -ENOENT;
 253
 254	rb_erase(&qgroup->node, &fs_info->qgroup_tree);
 255	__del_qgroup_rb(qgroup);
 256	return 0;
 257}
 258
 259/* must be called with qgroup_lock held */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 260static int add_relation_rb(struct btrfs_fs_info *fs_info,
 
 261			   u64 memberid, u64 parentid)
 262{
 263	struct btrfs_qgroup *member;
 264	struct btrfs_qgroup *parent;
 265	struct btrfs_qgroup_list *list;
 266
 267	member = find_qgroup_rb(fs_info, memberid);
 268	parent = find_qgroup_rb(fs_info, parentid);
 269	if (!member || !parent)
 270		return -ENOENT;
 271
 272	list = kzalloc(sizeof(*list), GFP_ATOMIC);
 273	if (!list)
 274		return -ENOMEM;
 275
 276	list->group = parent;
 277	list->member = member;
 278	list_add_tail(&list->next_group, &member->groups);
 279	list_add_tail(&list->next_member, &parent->members);
 280
 281	return 0;
 282}
 283
 284/* must be called with qgroup_lock held */
 285static int del_relation_rb(struct btrfs_fs_info *fs_info,
 286			   u64 memberid, u64 parentid)
 287{
 288	struct btrfs_qgroup *member;
 289	struct btrfs_qgroup *parent;
 290	struct btrfs_qgroup_list *list;
 291
 292	member = find_qgroup_rb(fs_info, memberid);
 293	parent = find_qgroup_rb(fs_info, parentid);
 294	if (!member || !parent)
 295		return -ENOENT;
 296
 297	list_for_each_entry(list, &member->groups, next_group) {
 298		if (list->group == parent) {
 299			list_del(&list->next_group);
 300			list_del(&list->next_member);
 301			kfree(list);
 302			return 0;
 303		}
 304	}
 305	return -ENOENT;
 306}
 307
 308#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 309int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
 310			       u64 rfer, u64 excl)
 311{
 312	struct btrfs_qgroup *qgroup;
 313
 314	qgroup = find_qgroup_rb(fs_info, qgroupid);
 315	if (!qgroup)
 316		return -EINVAL;
 317	if (qgroup->rfer != rfer || qgroup->excl != excl)
 318		return -EINVAL;
 319	return 0;
 320}
 321#endif
 322
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 323/*
 324 * The full config is read in one go, only called from open_ctree()
 325 * It doesn't use any locking, as at this point we're still single-threaded
 326 */
 327int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
 328{
 329	struct btrfs_key key;
 330	struct btrfs_key found_key;
 331	struct btrfs_root *quota_root = fs_info->quota_root;
 332	struct btrfs_path *path = NULL;
 333	struct extent_buffer *l;
 334	int slot;
 335	int ret = 0;
 336	u64 flags = 0;
 337	u64 rescan_progress = 0;
 338
 339	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
 340		return 0;
 341
 342	fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 343	if (!fs_info->qgroup_ulist) {
 344		ret = -ENOMEM;
 345		goto out;
 346	}
 347
 348	path = btrfs_alloc_path();
 349	if (!path) {
 350		ret = -ENOMEM;
 351		goto out;
 352	}
 353
 
 
 
 354	/* default this to quota off, in case no status key is found */
 355	fs_info->qgroup_flags = 0;
 356
 357	/*
 358	 * pass 1: read status, all qgroup infos and limits
 359	 */
 360	key.objectid = 0;
 361	key.type = 0;
 362	key.offset = 0;
 363	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
 364	if (ret)
 365		goto out;
 366
 367	while (1) {
 368		struct btrfs_qgroup *qgroup;
 369
 370		slot = path->slots[0];
 371		l = path->nodes[0];
 372		btrfs_item_key_to_cpu(l, &found_key, slot);
 373
 374		if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
 375			struct btrfs_qgroup_status_item *ptr;
 376
 377			ptr = btrfs_item_ptr(l, slot,
 378					     struct btrfs_qgroup_status_item);
 379
 380			if (btrfs_qgroup_status_version(l, ptr) !=
 381			    BTRFS_QGROUP_STATUS_VERSION) {
 382				btrfs_err(fs_info,
 383				 "old qgroup version, quota disabled");
 384				goto out;
 385			}
 386			if (btrfs_qgroup_status_generation(l, ptr) !=
 387			    fs_info->generation) {
 388				flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 
 
 389				btrfs_err(fs_info,
 390					"qgroup generation mismatch, marked as inconsistent");
 391			}
 392			fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
 393									  ptr);
 394			rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
 395			goto next1;
 396		}
 397
 398		if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
 399		    found_key.type != BTRFS_QGROUP_LIMIT_KEY)
 400			goto next1;
 401
 402		qgroup = find_qgroup_rb(fs_info, found_key.offset);
 403		if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
 404		    (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
 405			btrfs_err(fs_info, "inconsistent qgroup config");
 406			flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 407		}
 408		if (!qgroup) {
 409			qgroup = add_qgroup_rb(fs_info, found_key.offset);
 410			if (IS_ERR(qgroup)) {
 411				ret = PTR_ERR(qgroup);
 
 
 412				goto out;
 413			}
 
 414		}
 
 
 
 
 415		switch (found_key.type) {
 416		case BTRFS_QGROUP_INFO_KEY: {
 417			struct btrfs_qgroup_info_item *ptr;
 418
 419			ptr = btrfs_item_ptr(l, slot,
 420					     struct btrfs_qgroup_info_item);
 421			qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
 422			qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
 423			qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
 424			qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
 425			/* generation currently unused */
 426			break;
 427		}
 428		case BTRFS_QGROUP_LIMIT_KEY: {
 429			struct btrfs_qgroup_limit_item *ptr;
 430
 431			ptr = btrfs_item_ptr(l, slot,
 432					     struct btrfs_qgroup_limit_item);
 433			qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
 434			qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
 435			qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
 436			qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
 437			qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
 438			break;
 439		}
 440		}
 441next1:
 442		ret = btrfs_next_item(quota_root, path);
 443		if (ret < 0)
 444			goto out;
 445		if (ret)
 446			break;
 447	}
 448	btrfs_release_path(path);
 449
 450	/*
 451	 * pass 2: read all qgroup relations
 452	 */
 453	key.objectid = 0;
 454	key.type = BTRFS_QGROUP_RELATION_KEY;
 455	key.offset = 0;
 456	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
 457	if (ret)
 458		goto out;
 459	while (1) {
 
 
 460		slot = path->slots[0];
 461		l = path->nodes[0];
 462		btrfs_item_key_to_cpu(l, &found_key, slot);
 463
 464		if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
 465			goto next2;
 466
 467		if (found_key.objectid > found_key.offset) {
 468			/* parent <- member, not needed to build config */
 469			/* FIXME should we omit the key completely? */
 470			goto next2;
 471		}
 472
 473		ret = add_relation_rb(fs_info, found_key.objectid,
 
 
 
 
 
 474				      found_key.offset);
 
 475		if (ret == -ENOENT) {
 476			btrfs_warn(fs_info,
 477				"orphan qgroup relation 0x%llx->0x%llx",
 478				found_key.objectid, found_key.offset);
 479			ret = 0;	/* ignore the error */
 480		}
 481		if (ret)
 482			goto out;
 483next2:
 484		ret = btrfs_next_item(quota_root, path);
 485		if (ret < 0)
 486			goto out;
 487		if (ret)
 488			break;
 489	}
 490out:
 491	fs_info->qgroup_flags |= flags;
 492	if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
 493		clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
 494	else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
 495		 ret >= 0)
 496		ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
 497	btrfs_free_path(path);
 498
 499	if (ret < 0) {
 
 
 
 
 
 500		ulist_free(fs_info->qgroup_ulist);
 501		fs_info->qgroup_ulist = NULL;
 502		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
 
 503	}
 504
 505	return ret < 0 ? ret : 0;
 506}
 507
 508/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 509 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
 510 * first two are in single-threaded paths.And for the third one, we have set
 511 * quota_root to be null with qgroup_lock held before, so it is safe to clean
 512 * up the in-memory structures without qgroup_lock held.
 513 */
 514void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
 515{
 516	struct rb_node *n;
 517	struct btrfs_qgroup *qgroup;
 518
 519	while ((n = rb_first(&fs_info->qgroup_tree))) {
 520		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 521		rb_erase(n, &fs_info->qgroup_tree);
 522		__del_qgroup_rb(qgroup);
 
 
 523	}
 524	/*
 525	 * We call btrfs_free_qgroup_config() when unmounting
 526	 * filesystem and disabling quota, so we set qgroup_ulist
 527	 * to be null here to avoid double free.
 528	 */
 529	ulist_free(fs_info->qgroup_ulist);
 530	fs_info->qgroup_ulist = NULL;
 
 531}
 532
 533static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 534				    u64 dst)
 535{
 536	int ret;
 537	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 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_insert_empty_item(trans, quota_root, path, &key, 0);
 550
 551	btrfs_mark_buffer_dirty(path->nodes[0]);
 552
 553	btrfs_free_path(path);
 554	return ret;
 555}
 556
 557static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 558				    u64 dst)
 559{
 560	int ret;
 561	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 562	struct btrfs_path *path;
 563	struct btrfs_key key;
 564
 565	path = btrfs_alloc_path();
 566	if (!path)
 567		return -ENOMEM;
 568
 569	key.objectid = src;
 570	key.type = BTRFS_QGROUP_RELATION_KEY;
 571	key.offset = dst;
 572
 573	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 574	if (ret < 0)
 575		goto out;
 576
 577	if (ret > 0) {
 578		ret = -ENOENT;
 579		goto out;
 580	}
 581
 582	ret = btrfs_del_item(trans, quota_root, path);
 583out:
 584	btrfs_free_path(path);
 585	return ret;
 586}
 587
 588static int add_qgroup_item(struct btrfs_trans_handle *trans,
 589			   struct btrfs_root *quota_root, u64 qgroupid)
 590{
 591	int ret;
 592	struct btrfs_path *path;
 593	struct btrfs_qgroup_info_item *qgroup_info;
 594	struct btrfs_qgroup_limit_item *qgroup_limit;
 595	struct extent_buffer *leaf;
 596	struct btrfs_key key;
 597
 598	if (btrfs_is_testing(quota_root->fs_info))
 599		return 0;
 600
 601	path = btrfs_alloc_path();
 602	if (!path)
 603		return -ENOMEM;
 604
 605	key.objectid = 0;
 606	key.type = BTRFS_QGROUP_INFO_KEY;
 607	key.offset = qgroupid;
 608
 609	/*
 610	 * Avoid a transaction abort by catching -EEXIST here. In that
 611	 * case, we proceed by re-initializing the existing structure
 612	 * on disk.
 613	 */
 614
 615	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 616				      sizeof(*qgroup_info));
 617	if (ret && ret != -EEXIST)
 618		goto out;
 619
 620	leaf = path->nodes[0];
 621	qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
 622				 struct btrfs_qgroup_info_item);
 623	btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
 624	btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
 625	btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
 626	btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
 627	btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
 628
 629	btrfs_mark_buffer_dirty(leaf);
 630
 631	btrfs_release_path(path);
 632
 633	key.type = BTRFS_QGROUP_LIMIT_KEY;
 634	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 635				      sizeof(*qgroup_limit));
 636	if (ret && ret != -EEXIST)
 637		goto out;
 638
 639	leaf = path->nodes[0];
 640	qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
 641				  struct btrfs_qgroup_limit_item);
 642	btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
 643	btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
 644	btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
 645	btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
 646	btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
 647
 648	btrfs_mark_buffer_dirty(leaf);
 649
 650	ret = 0;
 651out:
 652	btrfs_free_path(path);
 653	return ret;
 654}
 655
 656static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid)
 657{
 658	int ret;
 659	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 660	struct btrfs_path *path;
 661	struct btrfs_key key;
 662
 663	path = btrfs_alloc_path();
 664	if (!path)
 665		return -ENOMEM;
 666
 667	key.objectid = 0;
 668	key.type = BTRFS_QGROUP_INFO_KEY;
 669	key.offset = qgroupid;
 670	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 671	if (ret < 0)
 672		goto out;
 673
 674	if (ret > 0) {
 675		ret = -ENOENT;
 676		goto out;
 677	}
 678
 679	ret = btrfs_del_item(trans, quota_root, path);
 680	if (ret)
 681		goto out;
 682
 683	btrfs_release_path(path);
 684
 685	key.type = BTRFS_QGROUP_LIMIT_KEY;
 686	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 687	if (ret < 0)
 688		goto out;
 689
 690	if (ret > 0) {
 691		ret = -ENOENT;
 692		goto out;
 693	}
 694
 695	ret = btrfs_del_item(trans, quota_root, path);
 696
 697out:
 698	btrfs_free_path(path);
 699	return ret;
 700}
 701
 702static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
 703				    struct btrfs_qgroup *qgroup)
 704{
 705	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 706	struct btrfs_path *path;
 707	struct btrfs_key key;
 708	struct extent_buffer *l;
 709	struct btrfs_qgroup_limit_item *qgroup_limit;
 710	int ret;
 711	int slot;
 712
 713	key.objectid = 0;
 714	key.type = BTRFS_QGROUP_LIMIT_KEY;
 715	key.offset = qgroup->qgroupid;
 716
 717	path = btrfs_alloc_path();
 718	if (!path)
 719		return -ENOMEM;
 720
 721	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 722	if (ret > 0)
 723		ret = -ENOENT;
 724
 725	if (ret)
 726		goto out;
 727
 728	l = path->nodes[0];
 729	slot = path->slots[0];
 730	qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
 731	btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
 732	btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
 733	btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
 734	btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
 735	btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
 736
 737	btrfs_mark_buffer_dirty(l);
 738
 739out:
 740	btrfs_free_path(path);
 741	return ret;
 742}
 743
 744static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
 745				   struct btrfs_qgroup *qgroup)
 746{
 747	struct btrfs_fs_info *fs_info = trans->fs_info;
 748	struct btrfs_root *quota_root = fs_info->quota_root;
 749	struct btrfs_path *path;
 750	struct btrfs_key key;
 751	struct extent_buffer *l;
 752	struct btrfs_qgroup_info_item *qgroup_info;
 753	int ret;
 754	int slot;
 755
 756	if (btrfs_is_testing(fs_info))
 757		return 0;
 758
 759	key.objectid = 0;
 760	key.type = BTRFS_QGROUP_INFO_KEY;
 761	key.offset = qgroup->qgroupid;
 762
 763	path = btrfs_alloc_path();
 764	if (!path)
 765		return -ENOMEM;
 766
 767	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 768	if (ret > 0)
 769		ret = -ENOENT;
 770
 771	if (ret)
 772		goto out;
 773
 774	l = path->nodes[0];
 775	slot = path->slots[0];
 776	qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 777	btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 778	btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 779	btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 780	btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 781	btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 782
 783	btrfs_mark_buffer_dirty(l);
 784
 785out:
 786	btrfs_free_path(path);
 787	return ret;
 788}
 789
 790static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
 791{
 792	struct btrfs_fs_info *fs_info = trans->fs_info;
 793	struct btrfs_root *quota_root = fs_info->quota_root;
 794	struct btrfs_path *path;
 795	struct btrfs_key key;
 796	struct extent_buffer *l;
 797	struct btrfs_qgroup_status_item *ptr;
 798	int ret;
 799	int slot;
 800
 801	key.objectid = 0;
 802	key.type = BTRFS_QGROUP_STATUS_KEY;
 803	key.offset = 0;
 804
 805	path = btrfs_alloc_path();
 806	if (!path)
 807		return -ENOMEM;
 808
 809	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 810	if (ret > 0)
 811		ret = -ENOENT;
 812
 813	if (ret)
 814		goto out;
 815
 816	l = path->nodes[0];
 817	slot = path->slots[0];
 818	ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 819	btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
 
 820	btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 821	btrfs_set_qgroup_status_rescan(l, ptr,
 822				fs_info->qgroup_rescan_progress.objectid);
 823
 824	btrfs_mark_buffer_dirty(l);
 825
 826out:
 827	btrfs_free_path(path);
 828	return ret;
 829}
 830
 831/*
 832 * called with qgroup_lock held
 833 */
 834static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 835				  struct btrfs_root *root)
 836{
 837	struct btrfs_path *path;
 838	struct btrfs_key key;
 839	struct extent_buffer *leaf = NULL;
 840	int ret;
 841	int nr = 0;
 842
 843	path = btrfs_alloc_path();
 844	if (!path)
 845		return -ENOMEM;
 846
 847	path->leave_spinning = 1;
 848
 849	key.objectid = 0;
 850	key.offset = 0;
 851	key.type = 0;
 852
 853	while (1) {
 854		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 855		if (ret < 0)
 856			goto out;
 857		leaf = path->nodes[0];
 858		nr = btrfs_header_nritems(leaf);
 859		if (!nr)
 860			break;
 861		/*
 862		 * delete the leaf one by one
 863		 * since the whole tree is going
 864		 * to be deleted.
 865		 */
 866		path->slots[0] = 0;
 867		ret = btrfs_del_items(trans, root, path, 0, nr);
 868		if (ret)
 869			goto out;
 870
 871		btrfs_release_path(path);
 872	}
 873	ret = 0;
 874out:
 875	btrfs_free_path(path);
 876	return ret;
 877}
 878
 879int btrfs_quota_enable(struct btrfs_fs_info *fs_info)
 
 880{
 881	struct btrfs_root *quota_root;
 882	struct btrfs_root *tree_root = fs_info->tree_root;
 883	struct btrfs_path *path = NULL;
 884	struct btrfs_qgroup_status_item *ptr;
 885	struct extent_buffer *leaf;
 886	struct btrfs_key key;
 887	struct btrfs_key found_key;
 888	struct btrfs_qgroup *qgroup = NULL;
 
 889	struct btrfs_trans_handle *trans = NULL;
 
 
 890	int ret = 0;
 891	int slot;
 892
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 893	mutex_lock(&fs_info->qgroup_ioctl_lock);
 894	if (fs_info->quota_root)
 895		goto out;
 896
 897	fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 898	if (!fs_info->qgroup_ulist) {
 899		ret = -ENOMEM;
 900		goto out;
 901	}
 902
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 903	/*
 904	 * 1 for quota root item
 905	 * 1 for BTRFS_QGROUP_STATUS item
 906	 *
 907	 * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items
 908	 * per subvolume. However those are not currently reserved since it
 909	 * would be a lot of overkill.
 910	 */
 911	trans = btrfs_start_transaction(tree_root, 2);
 
 
 912	if (IS_ERR(trans)) {
 913		ret = PTR_ERR(trans);
 914		trans = NULL;
 915		goto out;
 916	}
 917
 
 
 
 
 
 
 918	/*
 919	 * initially create the quota tree
 920	 */
 921	quota_root = btrfs_create_tree(trans, BTRFS_QUOTA_TREE_OBJECTID);
 922	if (IS_ERR(quota_root)) {
 923		ret =  PTR_ERR(quota_root);
 924		btrfs_abort_transaction(trans, ret);
 925		goto out;
 926	}
 927
 928	path = btrfs_alloc_path();
 929	if (!path) {
 930		ret = -ENOMEM;
 931		btrfs_abort_transaction(trans, ret);
 932		goto out_free_root;
 933	}
 934
 935	key.objectid = 0;
 936	key.type = BTRFS_QGROUP_STATUS_KEY;
 937	key.offset = 0;
 938
 939	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 940				      sizeof(*ptr));
 941	if (ret) {
 942		btrfs_abort_transaction(trans, ret);
 943		goto out_free_path;
 944	}
 945
 946	leaf = path->nodes[0];
 947	ptr = btrfs_item_ptr(leaf, path->slots[0],
 948				 struct btrfs_qgroup_status_item);
 949	btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
 950	btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
 951	fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
 952				BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 953	btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
 
 
 
 
 
 
 954	btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
 955
 956	btrfs_mark_buffer_dirty(leaf);
 957
 958	key.objectid = 0;
 959	key.type = BTRFS_ROOT_REF_KEY;
 960	key.offset = 0;
 961
 962	btrfs_release_path(path);
 963	ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
 964	if (ret > 0)
 965		goto out_add_root;
 966	if (ret < 0) {
 967		btrfs_abort_transaction(trans, ret);
 968		goto out_free_path;
 969	}
 970
 971	while (1) {
 972		slot = path->slots[0];
 973		leaf = path->nodes[0];
 974		btrfs_item_key_to_cpu(leaf, &found_key, slot);
 975
 976		if (found_key.type == BTRFS_ROOT_REF_KEY) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 977			ret = add_qgroup_item(trans, quota_root,
 978					      found_key.offset);
 979			if (ret) {
 980				btrfs_abort_transaction(trans, ret);
 981				goto out_free_path;
 982			}
 983
 984			qgroup = add_qgroup_rb(fs_info, found_key.offset);
 
 985			if (IS_ERR(qgroup)) {
 986				ret = PTR_ERR(qgroup);
 987				btrfs_abort_transaction(trans, ret);
 988				goto out_free_path;
 989			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 990		}
 991		ret = btrfs_next_item(tree_root, path);
 992		if (ret < 0) {
 993			btrfs_abort_transaction(trans, ret);
 994			goto out_free_path;
 995		}
 996		if (ret)
 997			break;
 998	}
 999
1000out_add_root:
1001	btrfs_release_path(path);
1002	ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
1003	if (ret) {
1004		btrfs_abort_transaction(trans, ret);
1005		goto out_free_path;
1006	}
1007
1008	qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
1009	if (IS_ERR(qgroup)) {
1010		ret = PTR_ERR(qgroup);
 
 
 
 
 
 
 
1011		btrfs_abort_transaction(trans, ret);
1012		goto out_free_path;
1013	}
1014
 
 
 
 
 
 
 
 
 
 
 
 
1015	ret = btrfs_commit_transaction(trans);
1016	trans = NULL;
 
1017	if (ret)
1018		goto out_free_path;
1019
1020	/*
1021	 * Set quota enabled flag after committing the transaction, to avoid
1022	 * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot
1023	 * creation.
1024	 */
1025	spin_lock(&fs_info->qgroup_lock);
1026	fs_info->quota_root = quota_root;
1027	set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
 
 
1028	spin_unlock(&fs_info->qgroup_lock);
1029
 
 
 
 
1030	ret = qgroup_rescan_init(fs_info, 0, 1);
1031	if (!ret) {
1032	        qgroup_rescan_zero_tracking(fs_info);
 
1033	        btrfs_queue_work(fs_info->qgroup_rescan_workers,
1034	                         &fs_info->qgroup_rescan_work);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1035	}
1036
1037out_free_path:
1038	btrfs_free_path(path);
1039out_free_root:
1040	if (ret) {
1041		free_extent_buffer(quota_root->node);
1042		free_extent_buffer(quota_root->commit_root);
1043		kfree(quota_root);
1044	}
1045out:
1046	if (ret) {
1047		ulist_free(fs_info->qgroup_ulist);
1048		fs_info->qgroup_ulist = NULL;
1049		if (trans)
1050			btrfs_end_transaction(trans);
1051	}
1052	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1053	return ret;
1054}
1055
1056int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
1057{
1058	struct btrfs_root *quota_root;
1059	struct btrfs_trans_handle *trans = NULL;
1060	int ret = 0;
1061
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1062	mutex_lock(&fs_info->qgroup_ioctl_lock);
1063	if (!fs_info->quota_root)
1064		goto out;
1065
1066	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1067	 * 1 For the root item
1068	 *
1069	 * We should also reserve enough items for the quota tree deletion in
1070	 * btrfs_clean_quota_tree but this is not done.
 
 
 
1071	 */
1072	trans = btrfs_start_transaction(fs_info->tree_root, 1);
 
 
1073	if (IS_ERR(trans)) {
1074		ret = PTR_ERR(trans);
 
 
1075		goto out;
1076	}
1077
1078	clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1079	btrfs_qgroup_wait_for_completion(fs_info, false);
 
1080	spin_lock(&fs_info->qgroup_lock);
1081	quota_root = fs_info->quota_root;
1082	fs_info->quota_root = NULL;
1083	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
 
 
1084	spin_unlock(&fs_info->qgroup_lock);
1085
1086	btrfs_free_qgroup_config(fs_info);
1087
1088	ret = btrfs_clean_quota_tree(trans, quota_root);
1089	if (ret) {
1090		btrfs_abort_transaction(trans, ret);
1091		goto end_trans;
1092	}
1093
1094	ret = btrfs_del_root(trans, &quota_root->root_key);
1095	if (ret) {
1096		btrfs_abort_transaction(trans, ret);
1097		goto end_trans;
1098	}
1099
 
1100	list_del(&quota_root->dirty_list);
 
1101
1102	btrfs_tree_lock(quota_root->node);
1103	btrfs_clean_tree_block(quota_root->node);
1104	btrfs_tree_unlock(quota_root->node);
1105	btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
 
1106
1107	free_extent_buffer(quota_root->node);
1108	free_extent_buffer(quota_root->commit_root);
1109	kfree(quota_root);
1110
1111end_trans:
1112	ret = btrfs_end_transaction(trans);
1113out:
1114	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
 
 
1115	return ret;
1116}
1117
1118static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1119			 struct btrfs_qgroup *qgroup)
1120{
1121	if (list_empty(&qgroup->dirty))
1122		list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1123}
1124
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1125/*
1126 * The easy accounting, we're updating qgroup relationship whose child qgroup
1127 * only has exclusive extents.
1128 *
1129 * In this case, all exclusive extents will also be exclusive for parent, so
1130 * excl/rfer just get added/removed.
1131 *
1132 * So is qgroup reservation space, which should also be added/removed to
1133 * parent.
1134 * Or when child tries to release reservation space, parent will underflow its
1135 * reservation (for relationship adding case).
1136 *
1137 * Caller should hold fs_info->qgroup_lock.
1138 */
1139static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1140				    struct ulist *tmp, u64 ref_root,
1141				    struct btrfs_qgroup *src, int sign)
1142{
1143	struct btrfs_qgroup *qgroup;
1144	struct btrfs_qgroup_list *glist;
1145	struct ulist_node *unode;
1146	struct ulist_iterator uiter;
1147	u64 num_bytes = src->excl;
1148	int ret = 0;
1149
1150	qgroup = find_qgroup_rb(fs_info, ref_root);
1151	if (!qgroup)
1152		goto out;
1153
1154	qgroup->rfer += sign * num_bytes;
1155	qgroup->rfer_cmpr += sign * num_bytes;
1156
1157	WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1158	qgroup->excl += sign * num_bytes;
1159	qgroup->excl_cmpr += sign * num_bytes;
1160
1161	if (sign > 0)
1162		qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1163	else
1164		qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1165
1166	qgroup_dirty(fs_info, qgroup);
1167
1168	/* Get all of the parent groups that contain this qgroup */
1169	list_for_each_entry(glist, &qgroup->groups, next_group) {
1170		ret = ulist_add(tmp, glist->group->qgroupid,
1171				qgroup_to_aux(glist->group), GFP_ATOMIC);
1172		if (ret < 0)
1173			goto out;
1174	}
1175
1176	/* Iterate all of the parents and adjust their reference counts */
1177	ULIST_ITER_INIT(&uiter);
1178	while ((unode = ulist_next(tmp, &uiter))) {
1179		qgroup = unode_aux_to_qgroup(unode);
1180		qgroup->rfer += sign * num_bytes;
1181		qgroup->rfer_cmpr += sign * num_bytes;
 
1182		WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1183		qgroup->excl += sign * num_bytes;
 
 
1184		if (sign > 0)
1185			qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1186		else
1187			qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1188		qgroup->excl_cmpr += sign * num_bytes;
1189		qgroup_dirty(fs_info, qgroup);
1190
1191		/* Add any parents of the parents */
1192		list_for_each_entry(glist, &qgroup->groups, next_group) {
1193			ret = ulist_add(tmp, glist->group->qgroupid,
1194					qgroup_to_aux(glist->group), GFP_ATOMIC);
1195			if (ret < 0)
1196				goto out;
1197		}
1198	}
1199	ret = 0;
1200out:
 
1201	return ret;
1202}
1203
1204
1205/*
1206 * Quick path for updating qgroup with only excl refs.
1207 *
1208 * In that case, just update all parent will be enough.
1209 * Or we needs to do a full rescan.
1210 * Caller should also hold fs_info->qgroup_lock.
1211 *
1212 * Return 0 for quick update, return >0 for need to full rescan
1213 * and mark INCONSISTENT flag.
1214 * Return < 0 for other error.
1215 */
1216static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1217				   struct ulist *tmp, u64 src, u64 dst,
1218				   int sign)
1219{
1220	struct btrfs_qgroup *qgroup;
1221	int ret = 1;
1222	int err = 0;
1223
1224	qgroup = find_qgroup_rb(fs_info, src);
1225	if (!qgroup)
1226		goto out;
1227	if (qgroup->excl == qgroup->rfer) {
1228		ret = 0;
1229		err = __qgroup_excl_accounting(fs_info, tmp, dst,
1230					       qgroup, sign);
1231		if (err < 0) {
1232			ret = err;
1233			goto out;
1234		}
1235	}
1236out:
1237	if (ret)
1238		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1239	return ret;
1240}
1241
1242int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1243			      u64 dst)
1244{
1245	struct btrfs_fs_info *fs_info = trans->fs_info;
1246	struct btrfs_root *quota_root;
1247	struct btrfs_qgroup *parent;
1248	struct btrfs_qgroup *member;
1249	struct btrfs_qgroup_list *list;
1250	struct ulist *tmp;
1251	int ret = 0;
1252
1253	/* Check the level of src and dst first */
1254	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1255		return -EINVAL;
1256
1257	tmp = ulist_alloc(GFP_KERNEL);
1258	if (!tmp)
1259		return -ENOMEM;
1260
1261	mutex_lock(&fs_info->qgroup_ioctl_lock);
1262	quota_root = fs_info->quota_root;
1263	if (!quota_root) {
1264		ret = -EINVAL;
1265		goto out;
1266	}
1267	member = find_qgroup_rb(fs_info, src);
1268	parent = find_qgroup_rb(fs_info, dst);
1269	if (!member || !parent) {
1270		ret = -EINVAL;
1271		goto out;
1272	}
1273
1274	/* check if such qgroup relation exist firstly */
1275	list_for_each_entry(list, &member->groups, next_group) {
1276		if (list->group == parent) {
1277			ret = -EEXIST;
1278			goto out;
1279		}
1280	}
1281
 
 
 
 
 
1282	ret = add_qgroup_relation_item(trans, src, dst);
1283	if (ret)
1284		goto out;
1285
1286	ret = add_qgroup_relation_item(trans, dst, src);
1287	if (ret) {
1288		del_qgroup_relation_item(trans, src, dst);
1289		goto out;
1290	}
1291
1292	spin_lock(&fs_info->qgroup_lock);
1293	ret = add_relation_rb(fs_info, src, dst);
 
1294	if (ret < 0) {
1295		spin_unlock(&fs_info->qgroup_lock);
1296		goto out;
1297	}
1298	ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1299	spin_unlock(&fs_info->qgroup_lock);
1300out:
 
1301	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1302	ulist_free(tmp);
1303	return ret;
1304}
1305
1306static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1307				 u64 dst)
1308{
1309	struct btrfs_fs_info *fs_info = trans->fs_info;
1310	struct btrfs_root *quota_root;
1311	struct btrfs_qgroup *parent;
1312	struct btrfs_qgroup *member;
1313	struct btrfs_qgroup_list *list;
1314	struct ulist *tmp;
1315	bool found = false;
1316	int ret = 0;
1317	int ret2;
1318
1319	tmp = ulist_alloc(GFP_KERNEL);
1320	if (!tmp)
1321		return -ENOMEM;
1322
1323	quota_root = fs_info->quota_root;
1324	if (!quota_root) {
1325		ret = -EINVAL;
1326		goto out;
1327	}
1328
1329	member = find_qgroup_rb(fs_info, src);
1330	parent = find_qgroup_rb(fs_info, dst);
1331	/*
1332	 * The parent/member pair doesn't exist, then try to delete the dead
1333	 * relation items only.
1334	 */
1335	if (!member || !parent)
1336		goto delete_item;
1337
1338	/* check if such qgroup relation exist firstly */
1339	list_for_each_entry(list, &member->groups, next_group) {
1340		if (list->group == parent) {
1341			found = true;
1342			break;
1343		}
1344	}
1345
1346delete_item:
1347	ret = del_qgroup_relation_item(trans, src, dst);
1348	if (ret < 0 && ret != -ENOENT)
1349		goto out;
1350	ret2 = del_qgroup_relation_item(trans, dst, src);
1351	if (ret2 < 0 && ret2 != -ENOENT)
1352		goto out;
1353
1354	/* At least one deletion succeeded, return 0 */
1355	if (!ret || !ret2)
1356		ret = 0;
1357
1358	if (found) {
1359		spin_lock(&fs_info->qgroup_lock);
1360		del_relation_rb(fs_info, src, dst);
1361		ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1362		spin_unlock(&fs_info->qgroup_lock);
1363	}
1364out:
1365	ulist_free(tmp);
1366	return ret;
1367}
1368
1369int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1370			      u64 dst)
1371{
1372	struct btrfs_fs_info *fs_info = trans->fs_info;
1373	int ret = 0;
1374
1375	mutex_lock(&fs_info->qgroup_ioctl_lock);
1376	ret = __del_qgroup_relation(trans, src, dst);
1377	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1378
1379	return ret;
1380}
1381
1382int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1383{
1384	struct btrfs_fs_info *fs_info = trans->fs_info;
1385	struct btrfs_root *quota_root;
1386	struct btrfs_qgroup *qgroup;
 
1387	int ret = 0;
1388
 
 
 
1389	mutex_lock(&fs_info->qgroup_ioctl_lock);
1390	quota_root = fs_info->quota_root;
1391	if (!quota_root) {
1392		ret = -EINVAL;
1393		goto out;
1394	}
 
1395	qgroup = find_qgroup_rb(fs_info, qgroupid);
1396	if (qgroup) {
1397		ret = -EEXIST;
1398		goto out;
1399	}
1400
 
 
 
 
 
 
1401	ret = add_qgroup_item(trans, quota_root, qgroupid);
1402	if (ret)
1403		goto out;
1404
1405	spin_lock(&fs_info->qgroup_lock);
1406	qgroup = add_qgroup_rb(fs_info, qgroupid);
1407	spin_unlock(&fs_info->qgroup_lock);
 
1408
1409	if (IS_ERR(qgroup))
1410		ret = PTR_ERR(qgroup);
1411out:
1412	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
1413	return ret;
1414}
1415
 
 
 
 
 
 
 
 
 
1416int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1417{
1418	struct btrfs_fs_info *fs_info = trans->fs_info;
1419	struct btrfs_root *quota_root;
1420	struct btrfs_qgroup *qgroup;
1421	struct btrfs_qgroup_list *list;
1422	int ret = 0;
1423
1424	mutex_lock(&fs_info->qgroup_ioctl_lock);
1425	quota_root = fs_info->quota_root;
1426	if (!quota_root) {
1427		ret = -EINVAL;
1428		goto out;
1429	}
1430
1431	qgroup = find_qgroup_rb(fs_info, qgroupid);
1432	if (!qgroup) {
1433		ret = -ENOENT;
1434		goto out;
1435	}
1436
 
 
 
 
 
1437	/* Check if there are no children of this qgroup */
1438	if (!list_empty(&qgroup->members)) {
1439		ret = -EBUSY;
1440		goto out;
1441	}
1442
1443	ret = del_qgroup_item(trans, qgroupid);
1444	if (ret && ret != -ENOENT)
1445		goto out;
1446
1447	while (!list_empty(&qgroup->groups)) {
1448		list = list_first_entry(&qgroup->groups,
1449					struct btrfs_qgroup_list, next_group);
1450		ret = __del_qgroup_relation(trans, qgroupid,
1451					    list->group->qgroupid);
1452		if (ret)
1453			goto out;
1454	}
1455
1456	spin_lock(&fs_info->qgroup_lock);
1457	del_qgroup_rb(fs_info, qgroupid);
1458	spin_unlock(&fs_info->qgroup_lock);
 
 
 
 
 
 
 
 
1459out:
1460	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1461	return ret;
1462}
1463
1464int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
1465		       struct btrfs_qgroup_limit *limit)
1466{
1467	struct btrfs_fs_info *fs_info = trans->fs_info;
1468	struct btrfs_root *quota_root;
1469	struct btrfs_qgroup *qgroup;
1470	int ret = 0;
1471	/* Sometimes we would want to clear the limit on this qgroup.
1472	 * To meet this requirement, we treat the -1 as a special value
1473	 * which tell kernel to clear the limit on this qgroup.
1474	 */
1475	const u64 CLEAR_VALUE = -1;
1476
1477	mutex_lock(&fs_info->qgroup_ioctl_lock);
1478	quota_root = fs_info->quota_root;
1479	if (!quota_root) {
1480		ret = -EINVAL;
1481		goto out;
1482	}
1483
1484	qgroup = find_qgroup_rb(fs_info, qgroupid);
1485	if (!qgroup) {
1486		ret = -ENOENT;
1487		goto out;
1488	}
1489
1490	spin_lock(&fs_info->qgroup_lock);
1491	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1492		if (limit->max_rfer == CLEAR_VALUE) {
1493			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1494			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1495			qgroup->max_rfer = 0;
1496		} else {
1497			qgroup->max_rfer = limit->max_rfer;
1498		}
1499	}
1500	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1501		if (limit->max_excl == CLEAR_VALUE) {
1502			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1503			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1504			qgroup->max_excl = 0;
1505		} else {
1506			qgroup->max_excl = limit->max_excl;
1507		}
1508	}
1509	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1510		if (limit->rsv_rfer == CLEAR_VALUE) {
1511			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1512			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1513			qgroup->rsv_rfer = 0;
1514		} else {
1515			qgroup->rsv_rfer = limit->rsv_rfer;
1516		}
1517	}
1518	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1519		if (limit->rsv_excl == CLEAR_VALUE) {
1520			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1521			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1522			qgroup->rsv_excl = 0;
1523		} else {
1524			qgroup->rsv_excl = limit->rsv_excl;
1525		}
1526	}
1527	qgroup->lim_flags |= limit->flags;
1528
1529	spin_unlock(&fs_info->qgroup_lock);
1530
1531	ret = update_qgroup_limit_item(trans, qgroup);
1532	if (ret) {
1533		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1534		btrfs_info(fs_info, "unable to update quota limit for %llu",
1535		       qgroupid);
1536	}
1537
1538out:
1539	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1540	return ret;
1541}
1542
 
 
 
 
 
 
 
 
 
 
 
1543int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1544				struct btrfs_delayed_ref_root *delayed_refs,
1545				struct btrfs_qgroup_extent_record *record)
1546{
1547	struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1548	struct rb_node *parent_node = NULL;
1549	struct btrfs_qgroup_extent_record *entry;
1550	u64 bytenr = record->bytenr;
1551
 
 
 
1552	lockdep_assert_held(&delayed_refs->lock);
1553	trace_btrfs_qgroup_trace_extent(fs_info, record);
1554
1555	while (*p) {
1556		parent_node = *p;
1557		entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1558				 node);
1559		if (bytenr < entry->bytenr) {
1560			p = &(*p)->rb_left;
1561		} else if (bytenr > entry->bytenr) {
1562			p = &(*p)->rb_right;
1563		} else {
1564			if (record->data_rsv && !entry->data_rsv) {
1565				entry->data_rsv = record->data_rsv;
1566				entry->data_rsv_refroot =
1567					record->data_rsv_refroot;
1568			}
1569			return 1;
1570		}
1571	}
1572
1573	rb_link_node(&record->node, parent_node, p);
1574	rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1575	return 0;
1576}
1577
1578int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1579				   struct btrfs_qgroup_extent_record *qrecord)
1580{
1581	struct ulist *old_root;
1582	u64 bytenr = qrecord->bytenr;
1583	int ret;
1584
1585	ret = btrfs_find_all_roots(NULL, fs_info, bytenr, 0, &old_root, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1586	if (ret < 0) {
1587		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1588		btrfs_warn(fs_info,
1589"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1590			ret);
1591		return 0;
1592	}
1593
1594	/*
1595	 * Here we don't need to get the lock of
1596	 * trans->transaction->delayed_refs, since inserted qrecord won't
1597	 * be deleted, only qrecord->node may be modified (new qrecord insert)
1598	 *
1599	 * So modifying qrecord->old_roots is safe here
1600	 */
1601	qrecord->old_roots = old_root;
1602	return 0;
1603}
1604
 
 
 
 
 
 
 
 
 
 
 
 
 
1605int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
1606			      u64 num_bytes, gfp_t gfp_flag)
1607{
1608	struct btrfs_fs_info *fs_info = trans->fs_info;
1609	struct btrfs_qgroup_extent_record *record;
1610	struct btrfs_delayed_ref_root *delayed_refs;
1611	int ret;
1612
1613	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)
1614	    || bytenr == 0 || num_bytes == 0)
1615		return 0;
1616	record = kzalloc(sizeof(*record), gfp_flag);
1617	if (!record)
1618		return -ENOMEM;
1619
1620	delayed_refs = &trans->transaction->delayed_refs;
1621	record->bytenr = bytenr;
1622	record->num_bytes = num_bytes;
1623	record->old_roots = NULL;
1624
1625	spin_lock(&delayed_refs->lock);
1626	ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
1627	spin_unlock(&delayed_refs->lock);
1628	if (ret > 0) {
1629		kfree(record);
1630		return 0;
1631	}
1632	return btrfs_qgroup_trace_extent_post(fs_info, record);
1633}
1634
 
 
 
 
 
 
1635int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
1636				  struct extent_buffer *eb)
1637{
1638	struct btrfs_fs_info *fs_info = trans->fs_info;
1639	int nr = btrfs_header_nritems(eb);
1640	int i, extent_type, ret;
1641	struct btrfs_key key;
1642	struct btrfs_file_extent_item *fi;
1643	u64 bytenr, num_bytes;
1644
1645	/* We can be called directly from walk_up_proc() */
1646	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1647		return 0;
1648
1649	for (i = 0; i < nr; i++) {
1650		btrfs_item_key_to_cpu(eb, &key, i);
1651
1652		if (key.type != BTRFS_EXTENT_DATA_KEY)
1653			continue;
1654
1655		fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
1656		/* filter out non qgroup-accountable extents  */
1657		extent_type = btrfs_file_extent_type(eb, fi);
1658
1659		if (extent_type == BTRFS_FILE_EXTENT_INLINE)
1660			continue;
1661
1662		bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
1663		if (!bytenr)
1664			continue;
1665
1666		num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
1667
1668		ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes,
1669						GFP_NOFS);
1670		if (ret)
1671			return ret;
1672	}
1673	cond_resched();
1674	return 0;
1675}
1676
1677/*
1678 * Walk up the tree from the bottom, freeing leaves and any interior
1679 * nodes which have had all slots visited. If a node (leaf or
1680 * interior) is freed, the node above it will have it's slot
1681 * incremented. The root node will never be freed.
1682 *
1683 * At the end of this function, we should have a path which has all
1684 * slots incremented to the next position for a search. If we need to
1685 * read a new node it will be NULL and the node above it will have the
1686 * correct slot selected for a later read.
1687 *
1688 * If we increment the root nodes slot counter past the number of
1689 * elements, 1 is returned to signal completion of the search.
1690 */
1691static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
1692{
1693	int level = 0;
1694	int nr, slot;
1695	struct extent_buffer *eb;
1696
1697	if (root_level == 0)
1698		return 1;
1699
1700	while (level <= root_level) {
1701		eb = path->nodes[level];
1702		nr = btrfs_header_nritems(eb);
1703		path->slots[level]++;
1704		slot = path->slots[level];
1705		if (slot >= nr || level == 0) {
1706			/*
1707			 * Don't free the root -  we will detect this
1708			 * condition after our loop and return a
1709			 * positive value for caller to stop walking the tree.
1710			 */
1711			if (level != root_level) {
1712				btrfs_tree_unlock_rw(eb, path->locks[level]);
1713				path->locks[level] = 0;
1714
1715				free_extent_buffer(eb);
1716				path->nodes[level] = NULL;
1717				path->slots[level] = 0;
1718			}
1719		} else {
1720			/*
1721			 * We have a valid slot to walk back down
1722			 * from. Stop here so caller can process these
1723			 * new nodes.
1724			 */
1725			break;
1726		}
1727
1728		level++;
1729	}
1730
1731	eb = path->nodes[root_level];
1732	if (path->slots[root_level] >= btrfs_header_nritems(eb))
1733		return 1;
1734
1735	return 0;
1736}
1737
1738/*
1739 * Helper function to trace a subtree tree block swap.
1740 *
1741 * The swap will happen in highest tree block, but there may be a lot of
1742 * tree blocks involved.
1743 *
1744 * For example:
1745 *  OO = Old tree blocks
1746 *  NN = New tree blocks allocated during balance
1747 *
1748 *           File tree (257)                  Reloc tree for 257
1749 * L2              OO                                NN
1750 *               /    \                            /    \
1751 * L1          OO      OO (a)                    OO      NN (a)
1752 *            / \     / \                       / \     / \
1753 * L0       OO   OO OO   OO                   OO   OO NN   NN
1754 *                  (b)  (c)                          (b)  (c)
1755 *
1756 * When calling qgroup_trace_extent_swap(), we will pass:
1757 * @src_eb = OO(a)
1758 * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
1759 * @dst_level = 0
1760 * @root_level = 1
1761 *
1762 * In that case, qgroup_trace_extent_swap() will search from OO(a) to
1763 * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
1764 *
1765 * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
1766 *
1767 * 1) Tree search from @src_eb
1768 *    It should acts as a simplified btrfs_search_slot().
1769 *    The key for search can be extracted from @dst_path->nodes[dst_level]
1770 *    (first key).
1771 *
1772 * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
1773 *    NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
1774 *    They should be marked during previous (@dst_level = 1) iteration.
1775 *
1776 * 3) Mark file extents in leaves dirty
1777 *    We don't have good way to pick out new file extents only.
1778 *    So we still follow the old method by scanning all file extents in
1779 *    the leave.
1780 *
1781 * This function can free us from keeping two paths, thus later we only need
1782 * to care about how to iterate all new tree blocks in reloc tree.
1783 */
1784static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
1785				    struct extent_buffer *src_eb,
1786				    struct btrfs_path *dst_path,
1787				    int dst_level, int root_level,
1788				    bool trace_leaf)
1789{
1790	struct btrfs_key key;
1791	struct btrfs_path *src_path;
1792	struct btrfs_fs_info *fs_info = trans->fs_info;
1793	u32 nodesize = fs_info->nodesize;
1794	int cur_level = root_level;
1795	int ret;
1796
1797	BUG_ON(dst_level > root_level);
1798	/* Level mismatch */
1799	if (btrfs_header_level(src_eb) != root_level)
1800		return -EINVAL;
1801
1802	src_path = btrfs_alloc_path();
1803	if (!src_path) {
1804		ret = -ENOMEM;
1805		goto out;
1806	}
1807
1808	if (dst_level)
1809		btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
1810	else
1811		btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
1812
1813	/* For src_path */
1814	extent_buffer_get(src_eb);
1815	src_path->nodes[root_level] = src_eb;
1816	src_path->slots[root_level] = dst_path->slots[root_level];
1817	src_path->locks[root_level] = 0;
1818
1819	/* A simplified version of btrfs_search_slot() */
1820	while (cur_level >= dst_level) {
1821		struct btrfs_key src_key;
1822		struct btrfs_key dst_key;
1823
1824		if (src_path->nodes[cur_level] == NULL) {
1825			struct btrfs_key first_key;
1826			struct extent_buffer *eb;
1827			int parent_slot;
1828			u64 child_gen;
1829			u64 child_bytenr;
1830
1831			eb = src_path->nodes[cur_level + 1];
1832			parent_slot = src_path->slots[cur_level + 1];
1833			child_bytenr = btrfs_node_blockptr(eb, parent_slot);
1834			child_gen = btrfs_node_ptr_generation(eb, parent_slot);
1835			btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
1836
1837			eb = read_tree_block(fs_info, child_bytenr, child_gen,
1838					     cur_level, &first_key);
1839			if (IS_ERR(eb)) {
1840				ret = PTR_ERR(eb);
1841				goto out;
1842			} else if (!extent_buffer_uptodate(eb)) {
1843				free_extent_buffer(eb);
1844				ret = -EIO;
1845				goto out;
1846			}
1847
1848			src_path->nodes[cur_level] = eb;
1849
1850			btrfs_tree_read_lock(eb);
1851			btrfs_set_lock_blocking_read(eb);
1852			src_path->locks[cur_level] = BTRFS_READ_LOCK_BLOCKING;
1853		}
1854
1855		src_path->slots[cur_level] = dst_path->slots[cur_level];
1856		if (cur_level) {
1857			btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
1858					&dst_key, dst_path->slots[cur_level]);
1859			btrfs_node_key_to_cpu(src_path->nodes[cur_level],
1860					&src_key, src_path->slots[cur_level]);
1861		} else {
1862			btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
1863					&dst_key, dst_path->slots[cur_level]);
1864			btrfs_item_key_to_cpu(src_path->nodes[cur_level],
1865					&src_key, src_path->slots[cur_level]);
1866		}
1867		/* Content mismatch, something went wrong */
1868		if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
1869			ret = -ENOENT;
1870			goto out;
1871		}
1872		cur_level--;
1873	}
1874
1875	/*
1876	 * Now both @dst_path and @src_path have been populated, record the tree
1877	 * blocks for qgroup accounting.
1878	 */
1879	ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
1880			nodesize, GFP_NOFS);
1881	if (ret < 0)
1882		goto out;
1883	ret = btrfs_qgroup_trace_extent(trans,
1884			dst_path->nodes[dst_level]->start,
1885			nodesize, GFP_NOFS);
1886	if (ret < 0)
1887		goto out;
1888
1889	/* Record leaf file extents */
1890	if (dst_level == 0 && trace_leaf) {
1891		ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
1892		if (ret < 0)
1893			goto out;
1894		ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
1895	}
1896out:
1897	btrfs_free_path(src_path);
1898	return ret;
1899}
1900
1901/*
1902 * Helper function to do recursive generation-aware depth-first search, to
1903 * locate all new tree blocks in a subtree of reloc tree.
1904 *
1905 * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
1906 *         reloc tree
1907 * L2         NN (a)
1908 *          /    \
1909 * L1    OO        NN (b)
1910 *      /  \      /  \
1911 * L0  OO  OO    OO  NN
1912 *               (c) (d)
1913 * If we pass:
1914 * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
1915 * @cur_level = 1
1916 * @root_level = 1
1917 *
1918 * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
1919 * above tree blocks along with their counter parts in file tree.
1920 * While during search, old tree blocks OO(c) will be skipped as tree block swap
1921 * won't affect OO(c).
1922 */
1923static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
1924					   struct extent_buffer *src_eb,
1925					   struct btrfs_path *dst_path,
1926					   int cur_level, int root_level,
1927					   u64 last_snapshot, bool trace_leaf)
1928{
1929	struct btrfs_fs_info *fs_info = trans->fs_info;
1930	struct extent_buffer *eb;
1931	bool need_cleanup = false;
1932	int ret = 0;
1933	int i;
1934
1935	/* Level sanity check */
1936	if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 ||
1937	    root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 ||
1938	    root_level < cur_level) {
1939		btrfs_err_rl(fs_info,
1940			"%s: bad levels, cur_level=%d root_level=%d",
1941			__func__, cur_level, root_level);
1942		return -EUCLEAN;
1943	}
1944
1945	/* Read the tree block if needed */
1946	if (dst_path->nodes[cur_level] == NULL) {
1947		struct btrfs_key first_key;
1948		int parent_slot;
1949		u64 child_gen;
1950		u64 child_bytenr;
1951
1952		/*
1953		 * dst_path->nodes[root_level] must be initialized before
1954		 * calling this function.
1955		 */
1956		if (cur_level == root_level) {
1957			btrfs_err_rl(fs_info,
1958	"%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
1959				__func__, root_level, root_level, cur_level);
1960			return -EUCLEAN;
1961		}
1962
1963		/*
1964		 * We need to get child blockptr/gen from parent before we can
1965		 * read it.
1966		  */
1967		eb = dst_path->nodes[cur_level + 1];
1968		parent_slot = dst_path->slots[cur_level + 1];
1969		child_bytenr = btrfs_node_blockptr(eb, parent_slot);
1970		child_gen = btrfs_node_ptr_generation(eb, parent_slot);
1971		btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
1972
1973		/* This node is old, no need to trace */
1974		if (child_gen < last_snapshot)
1975			goto out;
1976
1977		eb = read_tree_block(fs_info, child_bytenr, child_gen,
1978				     cur_level, &first_key);
1979		if (IS_ERR(eb)) {
1980			ret = PTR_ERR(eb);
1981			goto out;
1982		} else if (!extent_buffer_uptodate(eb)) {
1983			free_extent_buffer(eb);
1984			ret = -EIO;
1985			goto out;
1986		}
1987
1988		dst_path->nodes[cur_level] = eb;
1989		dst_path->slots[cur_level] = 0;
1990
1991		btrfs_tree_read_lock(eb);
1992		btrfs_set_lock_blocking_read(eb);
1993		dst_path->locks[cur_level] = BTRFS_READ_LOCK_BLOCKING;
1994		need_cleanup = true;
1995	}
1996
1997	/* Now record this tree block and its counter part for qgroups */
1998	ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
1999				       root_level, trace_leaf);
2000	if (ret < 0)
2001		goto cleanup;
2002
2003	eb = dst_path->nodes[cur_level];
2004
2005	if (cur_level > 0) {
2006		/* Iterate all child tree blocks */
2007		for (i = 0; i < btrfs_header_nritems(eb); i++) {
2008			/* Skip old tree blocks as they won't be swapped */
2009			if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
2010				continue;
2011			dst_path->slots[cur_level] = i;
2012
2013			/* Recursive call (at most 7 times) */
2014			ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
2015					dst_path, cur_level - 1, root_level,
2016					last_snapshot, trace_leaf);
2017			if (ret < 0)
2018				goto cleanup;
2019		}
2020	}
2021
2022cleanup:
2023	if (need_cleanup) {
2024		/* Clean up */
2025		btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2026				     dst_path->locks[cur_level]);
2027		free_extent_buffer(dst_path->nodes[cur_level]);
2028		dst_path->nodes[cur_level] = NULL;
2029		dst_path->slots[cur_level] = 0;
2030		dst_path->locks[cur_level] = 0;
2031	}
2032out:
2033	return ret;
2034}
2035
2036static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2037				struct extent_buffer *src_eb,
2038				struct extent_buffer *dst_eb,
2039				u64 last_snapshot, bool trace_leaf)
2040{
2041	struct btrfs_fs_info *fs_info = trans->fs_info;
2042	struct btrfs_path *dst_path = NULL;
2043	int level;
2044	int ret;
2045
2046	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2047		return 0;
2048
2049	/* Wrong parameter order */
2050	if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) {
2051		btrfs_err_rl(fs_info,
2052		"%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2053			     btrfs_header_generation(src_eb),
2054			     btrfs_header_generation(dst_eb));
2055		return -EUCLEAN;
2056	}
2057
2058	if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2059		ret = -EIO;
2060		goto out;
2061	}
2062
2063	level = btrfs_header_level(dst_eb);
2064	dst_path = btrfs_alloc_path();
2065	if (!dst_path) {
2066		ret = -ENOMEM;
2067		goto out;
2068	}
2069	/* For dst_path */
2070	extent_buffer_get(dst_eb);
2071	dst_path->nodes[level] = dst_eb;
2072	dst_path->slots[level] = 0;
2073	dst_path->locks[level] = 0;
2074
2075	/* Do the generation aware breadth-first search */
2076	ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2077					      level, last_snapshot, trace_leaf);
2078	if (ret < 0)
2079		goto out;
2080	ret = 0;
2081
2082out:
2083	btrfs_free_path(dst_path);
2084	if (ret < 0)
2085		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2086	return ret;
2087}
2088
 
 
 
 
 
 
 
 
 
 
2089int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
2090			       struct extent_buffer *root_eb,
2091			       u64 root_gen, int root_level)
2092{
2093	struct btrfs_fs_info *fs_info = trans->fs_info;
2094	int ret = 0;
2095	int level;
 
2096	struct extent_buffer *eb = root_eb;
2097	struct btrfs_path *path = NULL;
2098
2099	BUG_ON(root_level < 0 || root_level >= BTRFS_MAX_LEVEL);
2100	BUG_ON(root_eb == NULL);
2101
2102	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2103		return 0;
2104
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2105	if (!extent_buffer_uptodate(root_eb)) {
2106		ret = btrfs_read_buffer(root_eb, root_gen, root_level, NULL);
 
 
 
 
 
 
2107		if (ret)
2108			goto out;
2109	}
2110
2111	if (root_level == 0) {
2112		ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2113		goto out;
2114	}
2115
2116	path = btrfs_alloc_path();
2117	if (!path)
2118		return -ENOMEM;
2119
2120	/*
2121	 * Walk down the tree.  Missing extent blocks are filled in as
2122	 * we go. Metadata is accounted every time we read a new
2123	 * extent block.
2124	 *
2125	 * When we reach a leaf, we account for file extent items in it,
2126	 * walk back up the tree (adjusting slot pointers as we go)
2127	 * and restart the search process.
2128	 */
2129	extent_buffer_get(root_eb); /* For path */
2130	path->nodes[root_level] = root_eb;
2131	path->slots[root_level] = 0;
2132	path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2133walk_down:
2134	level = root_level;
2135	while (level >= 0) {
2136		if (path->nodes[level] == NULL) {
2137			struct btrfs_key first_key;
2138			int parent_slot;
2139			u64 child_gen;
2140			u64 child_bytenr;
2141
2142			/*
2143			 * We need to get child blockptr/gen from parent before
2144			 * we can read it.
2145			  */
2146			eb = path->nodes[level + 1];
2147			parent_slot = path->slots[level + 1];
2148			child_bytenr = btrfs_node_blockptr(eb, parent_slot);
2149			child_gen = btrfs_node_ptr_generation(eb, parent_slot);
2150			btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
2151
2152			eb = read_tree_block(fs_info, child_bytenr, child_gen,
2153					     level, &first_key);
2154			if (IS_ERR(eb)) {
2155				ret = PTR_ERR(eb);
2156				goto out;
2157			} else if (!extent_buffer_uptodate(eb)) {
2158				free_extent_buffer(eb);
2159				ret = -EIO;
2160				goto out;
2161			}
2162
2163			path->nodes[level] = eb;
2164			path->slots[level] = 0;
2165
2166			btrfs_tree_read_lock(eb);
2167			btrfs_set_lock_blocking_read(eb);
2168			path->locks[level] = BTRFS_READ_LOCK_BLOCKING;
2169
2170			ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2171							fs_info->nodesize,
2172							GFP_NOFS);
2173			if (ret)
2174				goto out;
2175		}
2176
2177		if (level == 0) {
2178			ret = btrfs_qgroup_trace_leaf_items(trans,
2179							    path->nodes[level]);
2180			if (ret)
2181				goto out;
2182
2183			/* Nonzero return here means we completed our search */
2184			ret = adjust_slots_upwards(path, root_level);
2185			if (ret)
2186				break;
2187
2188			/* Restart search with new slots */
2189			goto walk_down;
2190		}
2191
2192		level--;
2193	}
2194
2195	ret = 0;
2196out:
2197	btrfs_free_path(path);
2198
2199	return ret;
2200}
2201
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2202#define UPDATE_NEW	0
2203#define UPDATE_OLD	1
2204/*
2205 * Walk all of the roots that points to the bytenr and adjust their refcnts.
2206 */
2207static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2208				struct ulist *roots, struct ulist *tmp,
2209				struct ulist *qgroups, u64 seq, int update_old)
2210{
2211	struct ulist_node *unode;
2212	struct ulist_iterator uiter;
2213	struct ulist_node *tmp_unode;
2214	struct ulist_iterator tmp_uiter;
2215	struct btrfs_qgroup *qg;
2216	int ret = 0;
2217
2218	if (!roots)
2219		return 0;
2220	ULIST_ITER_INIT(&uiter);
2221	while ((unode = ulist_next(roots, &uiter))) {
 
 
2222		qg = find_qgroup_rb(fs_info, unode->val);
2223		if (!qg)
2224			continue;
2225
2226		ulist_reinit(tmp);
2227		ret = ulist_add(qgroups, qg->qgroupid, qgroup_to_aux(qg),
2228				GFP_ATOMIC);
2229		if (ret < 0)
2230			return ret;
2231		ret = ulist_add(tmp, qg->qgroupid, qgroup_to_aux(qg), GFP_ATOMIC);
2232		if (ret < 0)
2233			return ret;
2234		ULIST_ITER_INIT(&tmp_uiter);
2235		while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
2236			struct btrfs_qgroup_list *glist;
2237
2238			qg = unode_aux_to_qgroup(tmp_unode);
2239			if (update_old)
2240				btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2241			else
2242				btrfs_qgroup_update_new_refcnt(qg, seq, 1);
 
2243			list_for_each_entry(glist, &qg->groups, next_group) {
2244				ret = ulist_add(qgroups, glist->group->qgroupid,
2245						qgroup_to_aux(glist->group),
2246						GFP_ATOMIC);
2247				if (ret < 0)
2248					return ret;
2249				ret = ulist_add(tmp, glist->group->qgroupid,
2250						qgroup_to_aux(glist->group),
2251						GFP_ATOMIC);
2252				if (ret < 0)
2253					return ret;
2254			}
2255		}
 
2256	}
2257	return 0;
2258}
2259
2260/*
2261 * Update qgroup rfer/excl counters.
2262 * Rfer update is easy, codes can explain themselves.
2263 *
2264 * Excl update is tricky, the update is split into 2 part.
2265 * Part 1: Possible exclusive <-> sharing detect:
2266 *	|	A	|	!A	|
2267 *  -------------------------------------
2268 *  B	|	*	|	-	|
2269 *  -------------------------------------
2270 *  !B	|	+	|	**	|
2271 *  -------------------------------------
2272 *
2273 * Conditions:
2274 * A:	cur_old_roots < nr_old_roots	(not exclusive before)
2275 * !A:	cur_old_roots == nr_old_roots	(possible exclusive before)
2276 * B:	cur_new_roots < nr_new_roots	(not exclusive now)
2277 * !B:	cur_new_roots == nr_new_roots	(possible exclusive now)
2278 *
2279 * Results:
2280 * +: Possible sharing -> exclusive	-: Possible exclusive -> sharing
2281 * *: Definitely not changed.		**: Possible unchanged.
2282 *
2283 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2284 *
2285 * To make the logic clear, we first use condition A and B to split
2286 * combination into 4 results.
2287 *
2288 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2289 * only on variant maybe 0.
2290 *
2291 * Lastly, check result **, since there are 2 variants maybe 0, split them
2292 * again(2x2).
2293 * But this time we don't need to consider other things, the codes and logic
2294 * is easy to understand now.
2295 */
2296static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
2297				  struct ulist *qgroups,
2298				  u64 nr_old_roots,
2299				  u64 nr_new_roots,
2300				  u64 num_bytes, u64 seq)
2301{
2302	struct ulist_node *unode;
2303	struct ulist_iterator uiter;
2304	struct btrfs_qgroup *qg;
2305	u64 cur_new_count, cur_old_count;
2306
2307	ULIST_ITER_INIT(&uiter);
2308	while ((unode = ulist_next(qgroups, &uiter))) {
2309		bool dirty = false;
2310
2311		qg = unode_aux_to_qgroup(unode);
2312		cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2313		cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2314
2315		trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2316					     cur_new_count);
2317
2318		/* Rfer update part */
2319		if (cur_old_count == 0 && cur_new_count > 0) {
2320			qg->rfer += num_bytes;
2321			qg->rfer_cmpr += num_bytes;
2322			dirty = true;
2323		}
2324		if (cur_old_count > 0 && cur_new_count == 0) {
2325			qg->rfer -= num_bytes;
2326			qg->rfer_cmpr -= num_bytes;
2327			dirty = true;
2328		}
2329
2330		/* Excl update part */
2331		/* Exclusive/none -> shared case */
2332		if (cur_old_count == nr_old_roots &&
2333		    cur_new_count < nr_new_roots) {
2334			/* Exclusive -> shared */
2335			if (cur_old_count != 0) {
2336				qg->excl -= num_bytes;
2337				qg->excl_cmpr -= num_bytes;
2338				dirty = true;
2339			}
2340		}
2341
2342		/* Shared -> exclusive/none case */
2343		if (cur_old_count < nr_old_roots &&
2344		    cur_new_count == nr_new_roots) {
2345			/* Shared->exclusive */
2346			if (cur_new_count != 0) {
2347				qg->excl += num_bytes;
2348				qg->excl_cmpr += num_bytes;
2349				dirty = true;
2350			}
2351		}
2352
2353		/* Exclusive/none -> exclusive/none case */
2354		if (cur_old_count == nr_old_roots &&
2355		    cur_new_count == nr_new_roots) {
2356			if (cur_old_count == 0) {
2357				/* None -> exclusive/none */
2358
2359				if (cur_new_count != 0) {
2360					/* None -> exclusive */
2361					qg->excl += num_bytes;
2362					qg->excl_cmpr += num_bytes;
2363					dirty = true;
2364				}
2365				/* None -> none, nothing changed */
2366			} else {
2367				/* Exclusive -> exclusive/none */
2368
2369				if (cur_new_count == 0) {
2370					/* Exclusive -> none */
2371					qg->excl -= num_bytes;
2372					qg->excl_cmpr -= num_bytes;
2373					dirty = true;
2374				}
2375				/* Exclusive -> exclusive, nothing changed */
2376			}
2377		}
2378
2379		if (dirty)
2380			qgroup_dirty(fs_info, qg);
2381	}
2382	return 0;
2383}
2384
2385/*
2386 * Check if the @roots potentially is a list of fs tree roots
2387 *
2388 * Return 0 for definitely not a fs/subvol tree roots ulist
2389 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2390 *          one as well)
2391 */
2392static int maybe_fs_roots(struct ulist *roots)
2393{
2394	struct ulist_node *unode;
2395	struct ulist_iterator uiter;
2396
2397	/* Empty one, still possible for fs roots */
2398	if (!roots || roots->nnodes == 0)
2399		return 1;
2400
2401	ULIST_ITER_INIT(&uiter);
2402	unode = ulist_next(roots, &uiter);
2403	if (!unode)
2404		return 1;
2405
2406	/*
2407	 * If it contains fs tree roots, then it must belong to fs/subvol
2408	 * trees.
2409	 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2410	 */
2411	return is_fstree(unode->val);
2412}
2413
2414int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2415				u64 num_bytes, struct ulist *old_roots,
2416				struct ulist *new_roots)
2417{
2418	struct btrfs_fs_info *fs_info = trans->fs_info;
2419	struct ulist *qgroups = NULL;
2420	struct ulist *tmp = NULL;
2421	u64 seq;
2422	u64 nr_new_roots = 0;
2423	u64 nr_old_roots = 0;
2424	int ret = 0;
2425
2426	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2427		return 0;
 
 
 
 
 
2428
2429	if (new_roots) {
2430		if (!maybe_fs_roots(new_roots))
2431			goto out_free;
2432		nr_new_roots = new_roots->nnodes;
2433	}
2434	if (old_roots) {
2435		if (!maybe_fs_roots(old_roots))
2436			goto out_free;
2437		nr_old_roots = old_roots->nnodes;
2438	}
2439
2440	/* Quick exit, either not fs tree roots, or won't affect any qgroup */
2441	if (nr_old_roots == 0 && nr_new_roots == 0)
2442		goto out_free;
2443
2444	BUG_ON(!fs_info->quota_root);
2445
2446	trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2447					num_bytes, nr_old_roots, nr_new_roots);
2448
2449	qgroups = ulist_alloc(GFP_NOFS);
2450	if (!qgroups) {
2451		ret = -ENOMEM;
2452		goto out_free;
2453	}
2454	tmp = ulist_alloc(GFP_NOFS);
2455	if (!tmp) {
2456		ret = -ENOMEM;
2457		goto out_free;
2458	}
2459
2460	mutex_lock(&fs_info->qgroup_rescan_lock);
2461	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2462		if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2463			mutex_unlock(&fs_info->qgroup_rescan_lock);
2464			ret = 0;
2465			goto out_free;
2466		}
2467	}
2468	mutex_unlock(&fs_info->qgroup_rescan_lock);
2469
2470	spin_lock(&fs_info->qgroup_lock);
2471	seq = fs_info->qgroup_seq;
2472
2473	/* Update old refcnts using old_roots */
2474	ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
2475				   UPDATE_OLD);
2476	if (ret < 0)
2477		goto out;
2478
2479	/* Update new refcnts using new_roots */
2480	ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
2481				   UPDATE_NEW);
2482	if (ret < 0)
2483		goto out;
2484
2485	qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
2486			       num_bytes, seq);
2487
2488	/*
 
 
 
 
 
 
 
2489	 * Bump qgroup_seq to avoid seq overlap
2490	 */
2491	fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
2492out:
2493	spin_unlock(&fs_info->qgroup_lock);
2494out_free:
2495	ulist_free(tmp);
2496	ulist_free(qgroups);
2497	ulist_free(old_roots);
2498	ulist_free(new_roots);
2499	return ret;
2500}
2501
2502int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2503{
2504	struct btrfs_fs_info *fs_info = trans->fs_info;
2505	struct btrfs_qgroup_extent_record *record;
2506	struct btrfs_delayed_ref_root *delayed_refs;
2507	struct ulist *new_roots = NULL;
2508	struct rb_node *node;
2509	u64 num_dirty_extents = 0;
2510	u64 qgroup_to_skip;
2511	int ret = 0;
2512
 
 
 
2513	delayed_refs = &trans->transaction->delayed_refs;
2514	qgroup_to_skip = delayed_refs->qgroup_to_skip;
2515	while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2516		record = rb_entry(node, struct btrfs_qgroup_extent_record,
2517				  node);
2518
2519		num_dirty_extents++;
2520		trace_btrfs_qgroup_account_extents(fs_info, record);
2521
2522		if (!ret) {
 
 
 
 
 
 
2523			/*
2524			 * Old roots should be searched when inserting qgroup
2525			 * extent record
 
 
 
 
 
 
 
 
 
 
2526			 */
2527			if (WARN_ON(!record->old_roots)) {
2528				/* Search commit root to find old_roots */
2529				ret = btrfs_find_all_roots(NULL, fs_info,
2530						record->bytenr, 0,
2531						&record->old_roots, false);
2532				if (ret < 0)
2533					goto cleanup;
 
 
2534			}
2535
2536			/* Free the reserved data space */
2537			btrfs_qgroup_free_refroot(fs_info,
2538					record->data_rsv_refroot,
2539					record->data_rsv,
2540					BTRFS_QGROUP_RSV_DATA);
2541			/*
2542			 * Use SEQ_LAST as time_seq to do special search, which
2543			 * doesn't lock tree or delayed_refs and search current
2544			 * root. It's safe inside commit_transaction().
2545			 */
2546			ret = btrfs_find_all_roots(trans, fs_info,
2547				record->bytenr, SEQ_LAST, &new_roots, false);
 
2548			if (ret < 0)
2549				goto cleanup;
 
2550			if (qgroup_to_skip) {
2551				ulist_del(new_roots, qgroup_to_skip, 0);
2552				ulist_del(record->old_roots, qgroup_to_skip,
2553					  0);
2554			}
2555			ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2556							  record->num_bytes,
2557							  record->old_roots,
2558							  new_roots);
2559			record->old_roots = NULL;
2560			new_roots = NULL;
2561		}
2562cleanup:
2563		ulist_free(record->old_roots);
2564		ulist_free(new_roots);
2565		new_roots = NULL;
2566		rb_erase(node, &delayed_refs->dirty_extent_root);
2567		kfree(record);
2568
2569	}
2570	trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2571				       num_dirty_extents);
2572	return ret;
2573}
2574
2575/*
2576 * called from commit_transaction. Writes all changed qgroups to disk.
 
2577 */
2578int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
2579{
2580	struct btrfs_fs_info *fs_info = trans->fs_info;
2581	struct btrfs_root *quota_root = fs_info->quota_root;
2582	int ret = 0;
2583
2584	if (!quota_root)
 
 
 
 
 
 
 
 
2585		return ret;
2586
2587	spin_lock(&fs_info->qgroup_lock);
2588	while (!list_empty(&fs_info->dirty_qgroups)) {
2589		struct btrfs_qgroup *qgroup;
2590		qgroup = list_first_entry(&fs_info->dirty_qgroups,
2591					  struct btrfs_qgroup, dirty);
2592		list_del_init(&qgroup->dirty);
2593		spin_unlock(&fs_info->qgroup_lock);
2594		ret = update_qgroup_info_item(trans, qgroup);
2595		if (ret)
2596			fs_info->qgroup_flags |=
2597					BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2598		ret = update_qgroup_limit_item(trans, qgroup);
2599		if (ret)
2600			fs_info->qgroup_flags |=
2601					BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2602		spin_lock(&fs_info->qgroup_lock);
2603	}
2604	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2605		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
2606	else
2607		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
2608	spin_unlock(&fs_info->qgroup_lock);
2609
2610	ret = update_qgroup_status_item(trans);
2611	if (ret)
2612		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2613
2614	return ret;
2615}
2616
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2617/*
2618 * Copy the accounting information between qgroups. This is necessary
2619 * when a snapshot or a subvolume is created. Throwing an error will
2620 * cause a transaction abort so we take extra care here to only error
2621 * when a readonly fs is a reasonable outcome.
2622 */
2623int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
2624			 u64 objectid, struct btrfs_qgroup_inherit *inherit)
 
2625{
2626	int ret = 0;
2627	int i;
2628	u64 *i_qgroups;
2629	bool committing = false;
2630	struct btrfs_fs_info *fs_info = trans->fs_info;
2631	struct btrfs_root *quota_root;
2632	struct btrfs_qgroup *srcgroup;
2633	struct btrfs_qgroup *dstgroup;
 
 
 
 
2634	u32 level_size = 0;
2635	u64 nums;
2636
 
 
 
 
2637	/*
2638	 * There are only two callers of this function.
2639	 *
2640	 * One in create_subvol() in the ioctl context, which needs to hold
2641	 * the qgroup_ioctl_lock.
2642	 *
2643	 * The other one in create_pending_snapshot() where no other qgroup
2644	 * code can modify the fs as they all need to either start a new trans
2645	 * or hold a trans handler, thus we don't need to hold
2646	 * qgroup_ioctl_lock.
2647	 * This would avoid long and complex lock chain and make lockdep happy.
2648	 */
2649	spin_lock(&fs_info->trans_lock);
2650	if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
2651		committing = true;
2652	spin_unlock(&fs_info->trans_lock);
2653
2654	if (!committing)
2655		mutex_lock(&fs_info->qgroup_ioctl_lock);
2656	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2657		goto out;
2658
2659	quota_root = fs_info->quota_root;
2660	if (!quota_root) {
2661		ret = -EINVAL;
2662		goto out;
2663	}
2664
 
 
 
 
 
 
 
2665	if (inherit) {
2666		i_qgroups = (u64 *)(inherit + 1);
2667		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
2668		       2 * inherit->num_excl_copies;
2669		for (i = 0; i < nums; ++i) {
2670			srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
2671
2672			/*
2673			 * Zero out invalid groups so we can ignore
2674			 * them later.
2675			 */
2676			if (!srcgroup ||
2677			    ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
2678				*i_qgroups = 0ULL;
2679
2680			++i_qgroups;
2681		}
2682	}
2683
2684	/*
2685	 * create a tracking group for the subvol itself
2686	 */
2687	ret = add_qgroup_item(trans, quota_root, objectid);
2688	if (ret)
2689		goto out;
2690
2691	/*
2692	 * add qgroup to all inherited groups
2693	 */
2694	if (inherit) {
2695		i_qgroups = (u64 *)(inherit + 1);
2696		for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
2697			if (*i_qgroups == 0)
2698				continue;
2699			ret = add_qgroup_relation_item(trans, objectid,
2700						       *i_qgroups);
2701			if (ret && ret != -EEXIST)
2702				goto out;
2703			ret = add_qgroup_relation_item(trans, *i_qgroups,
2704						       objectid);
2705			if (ret && ret != -EEXIST)
2706				goto out;
2707		}
2708		ret = 0;
2709	}
2710
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2711
2712	spin_lock(&fs_info->qgroup_lock);
2713
2714	dstgroup = add_qgroup_rb(fs_info, objectid);
2715	if (IS_ERR(dstgroup)) {
2716		ret = PTR_ERR(dstgroup);
2717		goto unlock;
2718	}
2719
2720	if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
2721		dstgroup->lim_flags = inherit->lim.flags;
2722		dstgroup->max_rfer = inherit->lim.max_rfer;
2723		dstgroup->max_excl = inherit->lim.max_excl;
2724		dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
2725		dstgroup->rsv_excl = inherit->lim.rsv_excl;
2726
2727		ret = update_qgroup_limit_item(trans, dstgroup);
2728		if (ret) {
2729			fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2730			btrfs_info(fs_info,
2731				   "unable to update quota limit for %llu",
2732				   dstgroup->qgroupid);
2733			goto unlock;
2734		}
2735	}
2736
2737	if (srcid) {
2738		srcgroup = find_qgroup_rb(fs_info, srcid);
2739		if (!srcgroup)
2740			goto unlock;
2741
2742		/*
2743		 * We call inherit after we clone the root in order to make sure
2744		 * our counts don't go crazy, so at this point the only
2745		 * difference between the two roots should be the root node.
2746		 */
2747		level_size = fs_info->nodesize;
2748		dstgroup->rfer = srcgroup->rfer;
2749		dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
2750		dstgroup->excl = level_size;
2751		dstgroup->excl_cmpr = level_size;
2752		srcgroup->excl = level_size;
2753		srcgroup->excl_cmpr = level_size;
2754
2755		/* inherit the limit info */
2756		dstgroup->lim_flags = srcgroup->lim_flags;
2757		dstgroup->max_rfer = srcgroup->max_rfer;
2758		dstgroup->max_excl = srcgroup->max_excl;
2759		dstgroup->rsv_rfer = srcgroup->rsv_rfer;
2760		dstgroup->rsv_excl = srcgroup->rsv_excl;
2761
2762		qgroup_dirty(fs_info, dstgroup);
2763		qgroup_dirty(fs_info, srcgroup);
2764	}
2765
2766	if (!inherit)
2767		goto unlock;
2768
2769	i_qgroups = (u64 *)(inherit + 1);
2770	for (i = 0; i < inherit->num_qgroups; ++i) {
2771		if (*i_qgroups) {
2772			ret = add_relation_rb(fs_info, objectid, *i_qgroups);
 
 
2773			if (ret)
2774				goto unlock;
2775		}
2776		++i_qgroups;
 
 
 
 
 
 
 
2777	}
2778
2779	for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
2780		struct btrfs_qgroup *src;
2781		struct btrfs_qgroup *dst;
2782
2783		if (!i_qgroups[0] || !i_qgroups[1])
2784			continue;
2785
2786		src = find_qgroup_rb(fs_info, i_qgroups[0]);
2787		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2788
2789		if (!src || !dst) {
2790			ret = -EINVAL;
2791			goto unlock;
2792		}
2793
2794		dst->rfer = src->rfer - level_size;
2795		dst->rfer_cmpr = src->rfer_cmpr - level_size;
 
 
 
2796	}
2797	for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
2798		struct btrfs_qgroup *src;
2799		struct btrfs_qgroup *dst;
2800
2801		if (!i_qgroups[0] || !i_qgroups[1])
2802			continue;
2803
2804		src = find_qgroup_rb(fs_info, i_qgroups[0]);
2805		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2806
2807		if (!src || !dst) {
2808			ret = -EINVAL;
2809			goto unlock;
2810		}
2811
2812		dst->excl = src->excl + level_size;
2813		dst->excl_cmpr = src->excl_cmpr + level_size;
 
2814	}
2815
2816unlock:
2817	spin_unlock(&fs_info->qgroup_lock);
 
 
2818out:
2819	if (!committing)
2820		mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
 
 
 
 
 
2821	return ret;
2822}
2823
2824/*
2825 * Two limits to commit transaction in advance.
2826 *
2827 * For RATIO, it will be 1/RATIO of the remaining limit as threshold.
2828 * For SIZE, it will be in byte unit as threshold.
2829 */
2830#define QGROUP_FREE_RATIO		32
2831#define QGROUP_FREE_SIZE		SZ_32M
2832static bool qgroup_check_limits(struct btrfs_fs_info *fs_info,
2833				const struct btrfs_qgroup *qg, u64 num_bytes)
2834{
2835	u64 free;
2836	u64 threshold;
2837
2838	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2839	    qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
2840		return false;
2841
2842	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2843	    qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
2844		return false;
2845
2846	/*
2847	 * Even if we passed the check, it's better to check if reservation
2848	 * for meta_pertrans is pushing us near limit.
2849	 * If there is too much pertrans reservation or it's near the limit,
2850	 * let's try commit transaction to free some, using transaction_kthread
2851	 */
2852	if ((qg->lim_flags & (BTRFS_QGROUP_LIMIT_MAX_RFER |
2853			      BTRFS_QGROUP_LIMIT_MAX_EXCL))) {
2854		if (qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
2855			free = qg->max_excl - qgroup_rsv_total(qg) - qg->excl;
2856			threshold = min_t(u64, qg->max_excl / QGROUP_FREE_RATIO,
2857					  QGROUP_FREE_SIZE);
2858		} else {
2859			free = qg->max_rfer - qgroup_rsv_total(qg) - qg->rfer;
2860			threshold = min_t(u64, qg->max_rfer / QGROUP_FREE_RATIO,
2861					  QGROUP_FREE_SIZE);
2862		}
2863
2864		/*
2865		 * Use transaction_kthread to commit transaction, so we no
2866		 * longer need to bother nested transaction nor lock context.
2867		 */
2868		if (free < threshold)
2869			btrfs_commit_transaction_locksafe(fs_info);
2870	}
2871
2872	return true;
2873}
2874
2875static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
2876			  enum btrfs_qgroup_rsv_type type)
2877{
2878	struct btrfs_root *quota_root;
2879	struct btrfs_qgroup *qgroup;
2880	struct btrfs_fs_info *fs_info = root->fs_info;
2881	u64 ref_root = root->root_key.objectid;
2882	int ret = 0;
2883	struct ulist_node *unode;
2884	struct ulist_iterator uiter;
2885
2886	if (!is_fstree(ref_root))
2887		return 0;
2888
2889	if (num_bytes == 0)
2890		return 0;
2891
2892	if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
2893	    capable(CAP_SYS_RESOURCE))
2894		enforce = false;
2895
2896	spin_lock(&fs_info->qgroup_lock);
2897	quota_root = fs_info->quota_root;
2898	if (!quota_root)
2899		goto out;
2900
2901	qgroup = find_qgroup_rb(fs_info, ref_root);
2902	if (!qgroup)
2903		goto out;
2904
2905	/*
2906	 * in a first step, we check all affected qgroups if any limits would
2907	 * be exceeded
2908	 */
2909	ulist_reinit(fs_info->qgroup_ulist);
2910	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2911			qgroup_to_aux(qgroup), GFP_ATOMIC);
2912	if (ret < 0)
2913		goto out;
2914	ULIST_ITER_INIT(&uiter);
2915	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2916		struct btrfs_qgroup *qg;
2917		struct btrfs_qgroup_list *glist;
2918
2919		qg = unode_aux_to_qgroup(unode);
2920
2921		if (enforce && !qgroup_check_limits(fs_info, qg, num_bytes)) {
2922			ret = -EDQUOT;
2923			goto out;
2924		}
2925
2926		list_for_each_entry(glist, &qg->groups, next_group) {
2927			ret = ulist_add(fs_info->qgroup_ulist,
2928					glist->group->qgroupid,
2929					qgroup_to_aux(glist->group), GFP_ATOMIC);
2930			if (ret < 0)
2931				goto out;
2932		}
2933	}
 
2934	ret = 0;
2935	/*
2936	 * no limits exceeded, now record the reservation into all qgroups
2937	 */
2938	ULIST_ITER_INIT(&uiter);
2939	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2940		struct btrfs_qgroup *qg;
2941
2942		qg = unode_aux_to_qgroup(unode);
2943
2944		qgroup_rsv_add(fs_info, qg, num_bytes, type);
2945	}
2946
2947out:
 
2948	spin_unlock(&fs_info->qgroup_lock);
2949	return ret;
2950}
2951
2952/*
2953 * Free @num_bytes of reserved space with @type for qgroup.  (Normally level 0
2954 * qgroup).
2955 *
2956 * Will handle all higher level qgroup too.
2957 *
2958 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
2959 * This special case is only used for META_PERTRANS type.
2960 */
2961void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
2962			       u64 ref_root, u64 num_bytes,
2963			       enum btrfs_qgroup_rsv_type type)
2964{
2965	struct btrfs_root *quota_root;
2966	struct btrfs_qgroup *qgroup;
2967	struct ulist_node *unode;
2968	struct ulist_iterator uiter;
2969	int ret = 0;
2970
2971	if (!is_fstree(ref_root))
2972		return;
2973
2974	if (num_bytes == 0)
2975		return;
2976
2977	if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
2978		WARN(1, "%s: Invalid type to free", __func__);
2979		return;
2980	}
2981	spin_lock(&fs_info->qgroup_lock);
2982
2983	quota_root = fs_info->quota_root;
2984	if (!quota_root)
2985		goto out;
2986
2987	qgroup = find_qgroup_rb(fs_info, ref_root);
2988	if (!qgroup)
2989		goto out;
2990
2991	if (num_bytes == (u64)-1)
2992		/*
2993		 * We're freeing all pertrans rsv, get reserved value from
2994		 * level 0 qgroup as real num_bytes to free.
2995		 */
2996		num_bytes = qgroup->rsv.values[type];
2997
2998	ulist_reinit(fs_info->qgroup_ulist);
2999	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3000			qgroup_to_aux(qgroup), GFP_ATOMIC);
3001	if (ret < 0)
3002		goto out;
3003	ULIST_ITER_INIT(&uiter);
3004	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3005		struct btrfs_qgroup *qg;
3006		struct btrfs_qgroup_list *glist;
3007
3008		qg = unode_aux_to_qgroup(unode);
3009
3010		qgroup_rsv_release(fs_info, qg, num_bytes, type);
3011
3012		list_for_each_entry(glist, &qg->groups, next_group) {
3013			ret = ulist_add(fs_info->qgroup_ulist,
3014					glist->group->qgroupid,
3015					qgroup_to_aux(glist->group), GFP_ATOMIC);
3016			if (ret < 0)
3017				goto out;
3018		}
3019	}
3020
3021out:
 
3022	spin_unlock(&fs_info->qgroup_lock);
3023}
3024
3025/*
3026 * Check if the leaf is the last leaf. Which means all node pointers
3027 * are at their last position.
3028 */
3029static bool is_last_leaf(struct btrfs_path *path)
3030{
3031	int i;
3032
3033	for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3034		if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3035			return false;
3036	}
3037	return true;
3038}
3039
3040/*
3041 * returns < 0 on error, 0 when more leafs are to be scanned.
3042 * returns 1 when done.
3043 */
3044static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3045			      struct btrfs_path *path)
3046{
3047	struct btrfs_fs_info *fs_info = trans->fs_info;
 
3048	struct btrfs_key found;
3049	struct extent_buffer *scratch_leaf = NULL;
3050	struct ulist *roots = NULL;
3051	u64 num_bytes;
3052	bool done;
3053	int slot;
3054	int ret;
3055
 
 
 
3056	mutex_lock(&fs_info->qgroup_rescan_lock);
3057	ret = btrfs_search_slot_for_read(fs_info->extent_root,
 
 
3058					 &fs_info->qgroup_rescan_progress,
3059					 path, 1, 0);
3060
3061	btrfs_debug(fs_info,
3062		"current progress key (%llu %u %llu), search_slot ret %d",
3063		fs_info->qgroup_rescan_progress.objectid,
3064		fs_info->qgroup_rescan_progress.type,
3065		fs_info->qgroup_rescan_progress.offset, ret);
3066
3067	if (ret) {
3068		/*
3069		 * The rescan is about to end, we will not be scanning any
3070		 * further blocks. We cannot unset the RESCAN flag here, because
3071		 * we want to commit the transaction if everything went well.
3072		 * To make the live accounting work in this phase, we set our
3073		 * scan progress pointer such that every real extent objectid
3074		 * will be smaller.
3075		 */
3076		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3077		btrfs_release_path(path);
3078		mutex_unlock(&fs_info->qgroup_rescan_lock);
3079		return ret;
3080	}
3081	done = is_last_leaf(path);
3082
3083	btrfs_item_key_to_cpu(path->nodes[0], &found,
3084			      btrfs_header_nritems(path->nodes[0]) - 1);
3085	fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3086
3087	scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3088	if (!scratch_leaf) {
3089		ret = -ENOMEM;
3090		mutex_unlock(&fs_info->qgroup_rescan_lock);
3091		goto out;
3092	}
3093	slot = path->slots[0];
3094	btrfs_release_path(path);
3095	mutex_unlock(&fs_info->qgroup_rescan_lock);
3096
3097	for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
 
 
3098		btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3099		if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3100		    found.type != BTRFS_METADATA_ITEM_KEY)
3101			continue;
3102		if (found.type == BTRFS_METADATA_ITEM_KEY)
3103			num_bytes = fs_info->nodesize;
3104		else
3105			num_bytes = found.offset;
3106
3107		ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
3108					   &roots, false);
 
 
3109		if (ret < 0)
3110			goto out;
3111		/* For rescan, just pass old_roots as NULL */
3112		ret = btrfs_qgroup_account_extent(trans, found.objectid,
3113						  num_bytes, NULL, roots);
3114		if (ret < 0)
3115			goto out;
3116	}
3117out:
3118	if (scratch_leaf)
3119		free_extent_buffer(scratch_leaf);
3120
3121	if (done && !ret) {
3122		ret = 1;
3123		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3124	}
3125	return ret;
3126}
3127
 
 
 
 
 
 
 
 
 
 
 
 
 
3128static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3129{
3130	struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3131						     qgroup_rescan_work);
3132	struct btrfs_path *path;
3133	struct btrfs_trans_handle *trans = NULL;
3134	int err = -ENOMEM;
3135	int ret = 0;
 
 
 
 
 
3136
3137	path = btrfs_alloc_path();
3138	if (!path)
3139		goto out;
3140	/*
3141	 * Rescan should only search for commit root, and any later difference
3142	 * should be recorded by qgroup
3143	 */
3144	path->search_commit_root = 1;
3145	path->skip_locking = 1;
3146
3147	err = 0;
3148	while (!err && !btrfs_fs_closing(fs_info)) {
3149		trans = btrfs_start_transaction(fs_info->fs_root, 0);
3150		if (IS_ERR(trans)) {
3151			err = PTR_ERR(trans);
3152			break;
3153		}
3154		if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
3155			err = -EINTR;
3156		} else {
3157			err = qgroup_rescan_leaf(trans, path);
3158		}
3159		if (err > 0)
3160			btrfs_commit_transaction(trans);
3161		else
3162			btrfs_end_transaction(trans);
3163	}
3164
3165out:
3166	btrfs_free_path(path);
3167
3168	mutex_lock(&fs_info->qgroup_rescan_lock);
3169	if (err > 0 &&
3170	    fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3171		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3172	} else if (err < 0) {
3173		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3174	}
3175	mutex_unlock(&fs_info->qgroup_rescan_lock);
3176
3177	/*
3178	 * only update status, since the previous part has already updated the
3179	 * qgroup info.
 
 
 
3180	 */
3181	trans = btrfs_start_transaction(fs_info->quota_root, 1);
3182	if (IS_ERR(trans)) {
3183		err = PTR_ERR(trans);
 
 
 
 
 
 
 
3184		trans = NULL;
3185		btrfs_err(fs_info,
3186			  "fail to start transaction for status update: %d",
3187			  err);
3188	}
3189
3190	mutex_lock(&fs_info->qgroup_rescan_lock);
3191	if (!btrfs_fs_closing(fs_info))
 
3192		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3193	if (trans) {
3194		ret = update_qgroup_status_item(trans);
3195		if (ret < 0) {
3196			err = ret;
3197			btrfs_err(fs_info, "fail to update qgroup status: %d",
3198				  err);
3199		}
3200	}
3201	fs_info->qgroup_rescan_running = false;
 
3202	complete_all(&fs_info->qgroup_rescan_completion);
3203	mutex_unlock(&fs_info->qgroup_rescan_lock);
3204
3205	if (!trans)
3206		return;
3207
3208	btrfs_end_transaction(trans);
3209
3210	if (btrfs_fs_closing(fs_info)) {
3211		btrfs_info(fs_info, "qgroup scan paused");
 
 
3212	} else if (err >= 0) {
3213		btrfs_info(fs_info, "qgroup scan completed%s",
3214			err > 0 ? " (inconsistency flag cleared)" : "");
3215	} else {
3216		btrfs_err(fs_info, "qgroup scan failed with %d", err);
3217	}
3218}
3219
3220/*
3221 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3222 * memory required for the rescan context.
3223 */
3224static int
3225qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3226		   int init_flags)
3227{
3228	int ret = 0;
3229
 
 
 
 
 
3230	if (!init_flags) {
3231		/* we're resuming qgroup rescan at mount time */
3232		if (!(fs_info->qgroup_flags &
3233		      BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3234			btrfs_warn(fs_info,
3235			"qgroup rescan init failed, qgroup is not enabled");
3236			ret = -EINVAL;
3237		} else if (!(fs_info->qgroup_flags &
3238			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3239			btrfs_warn(fs_info,
3240			"qgroup rescan init failed, qgroup rescan is not queued");
3241			ret = -EINVAL;
3242		}
3243
3244		if (ret)
3245			return ret;
3246	}
3247
3248	mutex_lock(&fs_info->qgroup_rescan_lock);
3249	spin_lock(&fs_info->qgroup_lock);
3250
3251	if (init_flags) {
3252		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3253			btrfs_warn(fs_info,
3254				   "qgroup rescan is already in progress");
3255			ret = -EINPROGRESS;
3256		} else if (!(fs_info->qgroup_flags &
3257			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3258			btrfs_warn(fs_info,
3259			"qgroup rescan init failed, qgroup is not enabled");
3260			ret = -EINVAL;
 
 
 
3261		}
3262
3263		if (ret) {
3264			spin_unlock(&fs_info->qgroup_lock);
3265			mutex_unlock(&fs_info->qgroup_rescan_lock);
3266			return ret;
3267		}
3268		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3269	}
3270
3271	memset(&fs_info->qgroup_rescan_progress, 0,
3272		sizeof(fs_info->qgroup_rescan_progress));
 
 
3273	fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3274	init_completion(&fs_info->qgroup_rescan_completion);
3275	fs_info->qgroup_rescan_running = true;
3276
3277	spin_unlock(&fs_info->qgroup_lock);
3278	mutex_unlock(&fs_info->qgroup_rescan_lock);
3279
3280	memset(&fs_info->qgroup_rescan_work, 0,
3281	       sizeof(fs_info->qgroup_rescan_work));
3282	btrfs_init_work(&fs_info->qgroup_rescan_work,
3283			btrfs_qgroup_rescan_helper,
3284			btrfs_qgroup_rescan_worker, NULL, NULL);
3285	return 0;
3286}
3287
3288static void
3289qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3290{
3291	struct rb_node *n;
3292	struct btrfs_qgroup *qgroup;
3293
3294	spin_lock(&fs_info->qgroup_lock);
3295	/* clear all current qgroup tracking information */
3296	for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3297		qgroup = rb_entry(n, struct btrfs_qgroup, node);
3298		qgroup->rfer = 0;
3299		qgroup->rfer_cmpr = 0;
3300		qgroup->excl = 0;
3301		qgroup->excl_cmpr = 0;
3302		qgroup_dirty(fs_info, qgroup);
3303	}
3304	spin_unlock(&fs_info->qgroup_lock);
3305}
3306
3307int
3308btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3309{
3310	int ret = 0;
3311	struct btrfs_trans_handle *trans;
3312
3313	ret = qgroup_rescan_init(fs_info, 0, 1);
3314	if (ret)
3315		return ret;
3316
3317	/*
3318	 * We have set the rescan_progress to 0, which means no more
3319	 * delayed refs will be accounted by btrfs_qgroup_account_ref.
3320	 * However, btrfs_qgroup_account_ref may be right after its call
3321	 * to btrfs_find_all_roots, in which case it would still do the
3322	 * accounting.
3323	 * To solve this, we're committing the transaction, which will
3324	 * ensure we run all delayed refs and only after that, we are
3325	 * going to clear all tracking information for a clean start.
3326	 */
3327
3328	trans = btrfs_join_transaction(fs_info->fs_root);
3329	if (IS_ERR(trans)) {
3330		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3331		return PTR_ERR(trans);
3332	}
3333	ret = btrfs_commit_transaction(trans);
3334	if (ret) {
3335		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3336		return ret;
 
3337	}
3338
3339	qgroup_rescan_zero_tracking(fs_info);
3340
 
 
3341	btrfs_queue_work(fs_info->qgroup_rescan_workers,
3342			 &fs_info->qgroup_rescan_work);
 
3343
3344	return 0;
3345}
3346
3347int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3348				     bool interruptible)
3349{
3350	int running;
3351	int ret = 0;
3352
3353	mutex_lock(&fs_info->qgroup_rescan_lock);
3354	spin_lock(&fs_info->qgroup_lock);
3355	running = fs_info->qgroup_rescan_running;
3356	spin_unlock(&fs_info->qgroup_lock);
3357	mutex_unlock(&fs_info->qgroup_rescan_lock);
3358
3359	if (!running)
3360		return 0;
3361
3362	if (interruptible)
3363		ret = wait_for_completion_interruptible(
3364					&fs_info->qgroup_rescan_completion);
3365	else
3366		wait_for_completion(&fs_info->qgroup_rescan_completion);
3367
3368	return ret;
3369}
3370
3371/*
3372 * this is only called from open_ctree where we're still single threaded, thus
3373 * locking is omitted here.
3374 */
3375void
3376btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3377{
3378	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
 
 
3379		btrfs_queue_work(fs_info->qgroup_rescan_workers,
3380				 &fs_info->qgroup_rescan_work);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3381}
3382
3383/*
3384 * Reserve qgroup space for range [start, start + len).
3385 *
3386 * This function will either reserve space from related qgroups or doing
3387 * nothing if the range is already reserved.
3388 *
3389 * Return 0 for successful reserve
3390 * Return <0 for error (including -EQUOT)
3391 *
3392 * NOTE: this function may sleep for memory allocation.
3393 *       if btrfs_qgroup_reserve_data() is called multiple times with
3394 *       same @reserved, caller must ensure when error happens it's OK
3395 *       to free *ALL* reserved space.
 
 
 
 
 
 
 
 
3396 */
3397int btrfs_qgroup_reserve_data(struct inode *inode,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3398			struct extent_changeset **reserved_ret, u64 start,
3399			u64 len)
3400{
3401	struct btrfs_root *root = BTRFS_I(inode)->root;
3402	struct ulist_node *unode;
3403	struct ulist_iterator uiter;
3404	struct extent_changeset *reserved;
 
3405	u64 orig_reserved;
3406	u64 to_reserve;
3407	int ret;
3408
3409	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags) ||
3410	    !is_fstree(root->root_key.objectid) || len == 0)
3411		return 0;
3412
3413	/* @reserved parameter is mandatory for qgroup */
3414	if (WARN_ON(!reserved_ret))
3415		return -EINVAL;
3416	if (!*reserved_ret) {
 
3417		*reserved_ret = extent_changeset_alloc();
3418		if (!*reserved_ret)
3419			return -ENOMEM;
3420	}
3421	reserved = *reserved_ret;
3422	/* Record already reserved space */
3423	orig_reserved = reserved->bytes_changed;
3424	ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
3425			start + len -1, EXTENT_QGROUP_RESERVED, reserved);
3426
3427	/* Newly reserved space */
3428	to_reserve = reserved->bytes_changed - orig_reserved;
3429	trace_btrfs_qgroup_reserve_data(inode, start, len,
3430					to_reserve, QGROUP_RESERVE);
3431	if (ret < 0)
3432		goto cleanup;
3433	ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
3434	if (ret < 0)
3435		goto cleanup;
3436
3437	return ret;
3438
3439cleanup:
3440	/* cleanup *ALL* already reserved ranges */
3441	ULIST_ITER_INIT(&uiter);
3442	while ((unode = ulist_next(&reserved->range_changed, &uiter)))
3443		clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val,
3444				 unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL);
3445	/* Also free data bytes of already reserved one */
3446	btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid,
3447				  orig_reserved, BTRFS_QGROUP_RSV_DATA);
3448	extent_changeset_release(reserved);
3449	return ret;
3450}
3451
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3452/* Free ranges specified by @reserved, normally in error path */
3453static int qgroup_free_reserved_data(struct inode *inode,
3454			struct extent_changeset *reserved, u64 start, u64 len)
 
3455{
3456	struct btrfs_root *root = BTRFS_I(inode)->root;
3457	struct ulist_node *unode;
3458	struct ulist_iterator uiter;
3459	struct extent_changeset changeset;
3460	int freed = 0;
3461	int ret;
3462
3463	extent_changeset_init(&changeset);
3464	len = round_up(start + len, root->fs_info->sectorsize);
3465	start = round_down(start, root->fs_info->sectorsize);
3466
3467	ULIST_ITER_INIT(&uiter);
3468	while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
3469		u64 range_start = unode->val;
3470		/* unode->aux is the inclusive end */
3471		u64 range_len = unode->aux - range_start + 1;
3472		u64 free_start;
3473		u64 free_len;
3474
3475		extent_changeset_release(&changeset);
3476
3477		/* Only free range in range [start, start + len) */
3478		if (range_start >= start + len ||
3479		    range_start + range_len <= start)
3480			continue;
3481		free_start = max(range_start, start);
3482		free_len = min(start + len, range_start + range_len) -
3483			   free_start;
3484		/*
3485		 * TODO: To also modify reserved->ranges_reserved to reflect
3486		 * the modification.
3487		 *
3488		 * However as long as we free qgroup reserved according to
3489		 * EXTENT_QGROUP_RESERVED, we won't double free.
3490		 * So not need to rush.
3491		 */
3492		ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree,
3493				free_start, free_start + free_len - 1,
3494				EXTENT_QGROUP_RESERVED, &changeset);
3495		if (ret < 0)
3496			goto out;
3497		freed += changeset.bytes_changed;
3498	}
3499	btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
3500				  BTRFS_QGROUP_RSV_DATA);
3501	ret = freed;
 
 
3502out:
3503	extent_changeset_release(&changeset);
3504	return ret;
3505}
3506
3507static int __btrfs_qgroup_release_data(struct inode *inode,
3508			struct extent_changeset *reserved, u64 start, u64 len,
3509			int free)
3510{
3511	struct extent_changeset changeset;
3512	int trace_op = QGROUP_RELEASE;
3513	int ret;
3514
3515	if (!test_bit(BTRFS_FS_QUOTA_ENABLED,
3516		      &BTRFS_I(inode)->root->fs_info->flags))
3517		return 0;
 
 
 
3518
3519	/* In release case, we shouldn't have @reserved */
3520	WARN_ON(!free && reserved);
3521	if (free && reserved)
3522		return qgroup_free_reserved_data(inode, reserved, start, len);
3523	extent_changeset_init(&changeset);
3524	ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, start, 
3525			start + len -1, EXTENT_QGROUP_RESERVED, &changeset);
3526	if (ret < 0)
3527		goto out;
3528
3529	if (free)
3530		trace_op = QGROUP_FREE;
3531	trace_btrfs_qgroup_release_data(inode, start, len,
3532					changeset.bytes_changed, trace_op);
3533	if (free)
3534		btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
3535				BTRFS_I(inode)->root->root_key.objectid,
3536				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3537	ret = changeset.bytes_changed;
 
3538out:
3539	extent_changeset_release(&changeset);
3540	return ret;
3541}
3542
3543/*
3544 * Free a reserved space range from io_tree and related qgroups
3545 *
3546 * Should be called when a range of pages get invalidated before reaching disk.
3547 * Or for error cleanup case.
3548 * if @reserved is given, only reserved range in [@start, @start + @len) will
3549 * be freed.
3550 *
3551 * For data written to disk, use btrfs_qgroup_release_data().
3552 *
3553 * NOTE: This function may sleep for memory allocation.
3554 */
3555int btrfs_qgroup_free_data(struct inode *inode,
3556			struct extent_changeset *reserved, u64 start, u64 len)
 
3557{
3558	return __btrfs_qgroup_release_data(inode, reserved, start, len, 1);
3559}
3560
3561/*
3562 * Release a reserved space range from io_tree only.
3563 *
3564 * Should be called when a range of pages get written to disk and corresponding
3565 * FILE_EXTENT is inserted into corresponding root.
3566 *
3567 * Since new qgroup accounting framework will only update qgroup numbers at
3568 * commit_transaction() time, its reserved space shouldn't be freed from
3569 * related qgroups.
3570 *
3571 * But we should release the range from io_tree, to allow further write to be
3572 * COWed.
3573 *
3574 * NOTE: This function may sleep for memory allocation.
3575 */
3576int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
3577{
3578	return __btrfs_qgroup_release_data(inode, NULL, start, len, 0);
3579}
3580
3581static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3582			      enum btrfs_qgroup_rsv_type type)
3583{
3584	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3585	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
3586		return;
3587	if (num_bytes == 0)
3588		return;
3589
3590	spin_lock(&root->qgroup_meta_rsv_lock);
3591	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
3592		root->qgroup_meta_rsv_prealloc += num_bytes;
3593	else
3594		root->qgroup_meta_rsv_pertrans += num_bytes;
3595	spin_unlock(&root->qgroup_meta_rsv_lock);
3596}
3597
3598static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3599			     enum btrfs_qgroup_rsv_type type)
3600{
3601	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3602	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
3603		return 0;
3604	if (num_bytes == 0)
3605		return 0;
3606
3607	spin_lock(&root->qgroup_meta_rsv_lock);
3608	if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
3609		num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
3610				  num_bytes);
3611		root->qgroup_meta_rsv_prealloc -= num_bytes;
3612	} else {
3613		num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
3614				  num_bytes);
3615		root->qgroup_meta_rsv_pertrans -= num_bytes;
3616	}
3617	spin_unlock(&root->qgroup_meta_rsv_lock);
3618	return num_bytes;
3619}
3620
3621int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
3622				enum btrfs_qgroup_rsv_type type, bool enforce)
3623{
3624	struct btrfs_fs_info *fs_info = root->fs_info;
3625	int ret;
3626
3627	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3628	    !is_fstree(root->root_key.objectid) || num_bytes == 0)
3629		return 0;
3630
3631	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
3632	trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
3633	ret = qgroup_reserve(root, num_bytes, enforce, type);
3634	if (ret < 0)
3635		return ret;
3636	/*
3637	 * Record what we have reserved into root.
3638	 *
3639	 * To avoid quota disabled->enabled underflow.
3640	 * In that case, we may try to free space we haven't reserved
3641	 * (since quota was disabled), so record what we reserved into root.
3642	 * And ensure later release won't underflow this number.
3643	 */
3644	add_root_meta_rsv(root, num_bytes, type);
3645	return ret;
3646}
3647
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3648void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
3649{
3650	struct btrfs_fs_info *fs_info = root->fs_info;
3651
3652	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3653	    !is_fstree(root->root_key.objectid))
3654		return;
3655
3656	/* TODO: Update trace point to handle such free */
3657	trace_qgroup_meta_free_all_pertrans(root);
3658	/* Special value -1 means to free all reserved space */
3659	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
3660				  BTRFS_QGROUP_RSV_META_PERTRANS);
3661}
3662
3663void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
3664			      enum btrfs_qgroup_rsv_type type)
3665{
3666	struct btrfs_fs_info *fs_info = root->fs_info;
3667
3668	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3669	    !is_fstree(root->root_key.objectid))
3670		return;
3671
3672	/*
3673	 * reservation for META_PREALLOC can happen before quota is enabled,
3674	 * which can lead to underflow.
3675	 * Here ensure we will only free what we really have reserved.
3676	 */
3677	num_bytes = sub_root_meta_rsv(root, num_bytes, type);
3678	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
3679	trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
3680	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
3681				  num_bytes, type);
3682}
3683
3684static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
3685				int num_bytes)
3686{
3687	struct btrfs_root *quota_root = fs_info->quota_root;
3688	struct btrfs_qgroup *qgroup;
3689	struct ulist_node *unode;
3690	struct ulist_iterator uiter;
3691	int ret = 0;
3692
3693	if (num_bytes == 0)
3694		return;
3695	if (!quota_root)
3696		return;
3697
3698	spin_lock(&fs_info->qgroup_lock);
3699	qgroup = find_qgroup_rb(fs_info, ref_root);
3700	if (!qgroup)
3701		goto out;
3702	ulist_reinit(fs_info->qgroup_ulist);
3703	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3704		       qgroup_to_aux(qgroup), GFP_ATOMIC);
3705	if (ret < 0)
3706		goto out;
3707	ULIST_ITER_INIT(&uiter);
3708	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3709		struct btrfs_qgroup *qg;
3710		struct btrfs_qgroup_list *glist;
3711
3712		qg = unode_aux_to_qgroup(unode);
 
 
3713
3714		qgroup_rsv_release(fs_info, qg, num_bytes,
3715				BTRFS_QGROUP_RSV_META_PREALLOC);
3716		qgroup_rsv_add(fs_info, qg, num_bytes,
3717				BTRFS_QGROUP_RSV_META_PERTRANS);
3718		list_for_each_entry(glist, &qg->groups, next_group) {
3719			ret = ulist_add(fs_info->qgroup_ulist,
3720					glist->group->qgroupid,
3721					qgroup_to_aux(glist->group), GFP_ATOMIC);
3722			if (ret < 0)
3723				goto out;
3724		}
3725	}
3726out:
 
3727	spin_unlock(&fs_info->qgroup_lock);
3728}
3729
 
 
 
 
 
 
3730void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
3731{
3732	struct btrfs_fs_info *fs_info = root->fs_info;
3733
3734	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3735	    !is_fstree(root->root_key.objectid))
3736		return;
3737	/* Same as btrfs_qgroup_free_meta_prealloc() */
3738	num_bytes = sub_root_meta_rsv(root, num_bytes,
3739				      BTRFS_QGROUP_RSV_META_PREALLOC);
3740	trace_qgroup_meta_convert(root, num_bytes);
3741	qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
3742}
3743
3744/*
3745 * Check qgroup reserved space leaking, normally at destroy inode
3746 * time
3747 */
3748void btrfs_qgroup_check_reserved_leak(struct inode *inode)
3749{
3750	struct extent_changeset changeset;
3751	struct ulist_node *unode;
3752	struct ulist_iterator iter;
3753	int ret;
3754
3755	extent_changeset_init(&changeset);
3756	ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
3757			EXTENT_QGROUP_RESERVED, &changeset);
3758
3759	WARN_ON(ret < 0);
3760	if (WARN_ON(changeset.bytes_changed)) {
3761		ULIST_ITER_INIT(&iter);
3762		while ((unode = ulist_next(&changeset.range_changed, &iter))) {
3763			btrfs_warn(BTRFS_I(inode)->root->fs_info,
3764				"leaking qgroup reserved space, ino: %lu, start: %llu, end: %llu",
3765				inode->i_ino, unode->val, unode->aux);
3766		}
3767		btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
3768				BTRFS_I(inode)->root->root_key.objectid,
3769				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3770
3771	}
3772	extent_changeset_release(&changeset);
3773}
3774
3775void btrfs_qgroup_init_swapped_blocks(
3776	struct btrfs_qgroup_swapped_blocks *swapped_blocks)
3777{
3778	int i;
3779
3780	spin_lock_init(&swapped_blocks->lock);
3781	for (i = 0; i < BTRFS_MAX_LEVEL; i++)
3782		swapped_blocks->blocks[i] = RB_ROOT;
3783	swapped_blocks->swapped = false;
3784}
3785
3786/*
3787 * Delete all swapped blocks record of @root.
3788 * Every record here means we skipped a full subtree scan for qgroup.
3789 *
3790 * Gets called when committing one transaction.
3791 */
3792void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root)
3793{
3794	struct btrfs_qgroup_swapped_blocks *swapped_blocks;
3795	int i;
3796
3797	swapped_blocks = &root->swapped_blocks;
3798
3799	spin_lock(&swapped_blocks->lock);
3800	if (!swapped_blocks->swapped)
3801		goto out;
3802	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
3803		struct rb_root *cur_root = &swapped_blocks->blocks[i];
3804		struct btrfs_qgroup_swapped_block *entry;
3805		struct btrfs_qgroup_swapped_block *next;
3806
3807		rbtree_postorder_for_each_entry_safe(entry, next, cur_root,
3808						     node)
3809			kfree(entry);
3810		swapped_blocks->blocks[i] = RB_ROOT;
3811	}
3812	swapped_blocks->swapped = false;
3813out:
3814	spin_unlock(&swapped_blocks->lock);
3815}
3816
3817/*
3818 * Add subtree roots record into @subvol_root.
3819 *
3820 * @subvol_root:	tree root of the subvolume tree get swapped
3821 * @bg:			block group under balance
3822 * @subvol_parent/slot:	pointer to the subtree root in subvolume tree
3823 * @reloc_parent/slot:	pointer to the subtree root in reloc tree
3824 *			BOTH POINTERS ARE BEFORE TREE SWAP
3825 * @last_snapshot:	last snapshot generation of the subvolume tree
3826 */
3827int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
3828		struct btrfs_root *subvol_root,
3829		struct btrfs_block_group_cache *bg,
3830		struct extent_buffer *subvol_parent, int subvol_slot,
3831		struct extent_buffer *reloc_parent, int reloc_slot,
3832		u64 last_snapshot)
3833{
3834	struct btrfs_fs_info *fs_info = subvol_root->fs_info;
3835	struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks;
3836	struct btrfs_qgroup_swapped_block *block;
3837	struct rb_node **cur;
3838	struct rb_node *parent = NULL;
3839	int level = btrfs_header_level(subvol_parent) - 1;
3840	int ret = 0;
3841
3842	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
3843		return 0;
3844
3845	if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) >
3846	    btrfs_node_ptr_generation(reloc_parent, reloc_slot)) {
3847		btrfs_err_rl(fs_info,
3848		"%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu",
3849			__func__,
3850			btrfs_node_ptr_generation(subvol_parent, subvol_slot),
3851			btrfs_node_ptr_generation(reloc_parent, reloc_slot));
3852		return -EUCLEAN;
3853	}
3854
3855	block = kmalloc(sizeof(*block), GFP_NOFS);
3856	if (!block) {
3857		ret = -ENOMEM;
3858		goto out;
3859	}
3860
3861	/*
3862	 * @reloc_parent/slot is still before swap, while @block is going to
3863	 * record the bytenr after swap, so we do the swap here.
3864	 */
3865	block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot);
3866	block->subvol_generation = btrfs_node_ptr_generation(reloc_parent,
3867							     reloc_slot);
3868	block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot);
3869	block->reloc_generation = btrfs_node_ptr_generation(subvol_parent,
3870							    subvol_slot);
3871	block->last_snapshot = last_snapshot;
3872	block->level = level;
3873
3874	/*
3875	 * If we have bg == NULL, we're called from btrfs_recover_relocation(),
3876	 * no one else can modify tree blocks thus we qgroup will not change
3877	 * no matter the value of trace_leaf.
3878	 */
3879	if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA)
3880		block->trace_leaf = true;
3881	else
3882		block->trace_leaf = false;
3883	btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot);
3884
3885	/* Insert @block into @blocks */
3886	spin_lock(&blocks->lock);
3887	cur = &blocks->blocks[level].rb_node;
3888	while (*cur) {
3889		struct btrfs_qgroup_swapped_block *entry;
3890
3891		parent = *cur;
3892		entry = rb_entry(parent, struct btrfs_qgroup_swapped_block,
3893				 node);
3894
3895		if (entry->subvol_bytenr < block->subvol_bytenr) {
3896			cur = &(*cur)->rb_left;
3897		} else if (entry->subvol_bytenr > block->subvol_bytenr) {
3898			cur = &(*cur)->rb_right;
3899		} else {
3900			if (entry->subvol_generation !=
3901					block->subvol_generation ||
3902			    entry->reloc_bytenr != block->reloc_bytenr ||
3903			    entry->reloc_generation !=
3904					block->reloc_generation) {
3905				/*
3906				 * Duplicated but mismatch entry found.
3907				 * Shouldn't happen.
3908				 *
3909				 * Marking qgroup inconsistent should be enough
3910				 * for end users.
3911				 */
3912				WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
3913				ret = -EEXIST;
3914			}
3915			kfree(block);
3916			goto out_unlock;
3917		}
3918	}
3919	rb_link_node(&block->node, parent, cur);
3920	rb_insert_color(&block->node, &blocks->blocks[level]);
3921	blocks->swapped = true;
3922out_unlock:
3923	spin_unlock(&blocks->lock);
3924out:
3925	if (ret < 0)
3926		fs_info->qgroup_flags |=
3927			BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3928	return ret;
3929}
3930
3931/*
3932 * Check if the tree block is a subtree root, and if so do the needed
3933 * delayed subtree trace for qgroup.
3934 *
3935 * This is called during btrfs_cow_block().
3936 */
3937int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
3938					 struct btrfs_root *root,
3939					 struct extent_buffer *subvol_eb)
3940{
3941	struct btrfs_fs_info *fs_info = root->fs_info;
 
3942	struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks;
3943	struct btrfs_qgroup_swapped_block *block;
3944	struct extent_buffer *reloc_eb = NULL;
3945	struct rb_node *node;
3946	bool found = false;
3947	bool swapped = false;
3948	int level = btrfs_header_level(subvol_eb);
3949	int ret = 0;
3950	int i;
3951
3952	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
3953		return 0;
3954	if (!is_fstree(root->root_key.objectid) || !root->reloc_root)
3955		return 0;
3956
3957	spin_lock(&blocks->lock);
3958	if (!blocks->swapped) {
3959		spin_unlock(&blocks->lock);
3960		return 0;
3961	}
3962	node = blocks->blocks[level].rb_node;
3963
3964	while (node) {
3965		block = rb_entry(node, struct btrfs_qgroup_swapped_block, node);
3966		if (block->subvol_bytenr < subvol_eb->start) {
3967			node = node->rb_left;
3968		} else if (block->subvol_bytenr > subvol_eb->start) {
3969			node = node->rb_right;
3970		} else {
3971			found = true;
3972			break;
3973		}
3974	}
3975	if (!found) {
3976		spin_unlock(&blocks->lock);
3977		goto out;
3978	}
3979	/* Found one, remove it from @blocks first and update blocks->swapped */
3980	rb_erase(&block->node, &blocks->blocks[level]);
3981	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
3982		if (RB_EMPTY_ROOT(&blocks->blocks[i])) {
3983			swapped = true;
3984			break;
3985		}
3986	}
3987	blocks->swapped = swapped;
3988	spin_unlock(&blocks->lock);
3989
 
 
 
 
 
3990	/* Read out reloc subtree root */
3991	reloc_eb = read_tree_block(fs_info, block->reloc_bytenr,
3992				   block->reloc_generation, block->level,
3993				   &block->first_key);
3994	if (IS_ERR(reloc_eb)) {
3995		ret = PTR_ERR(reloc_eb);
3996		reloc_eb = NULL;
3997		goto free_out;
3998	}
3999	if (!extent_buffer_uptodate(reloc_eb)) {
4000		ret = -EIO;
4001		goto free_out;
4002	}
4003
4004	ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb,
4005			block->last_snapshot, block->trace_leaf);
4006free_out:
4007	kfree(block);
4008	free_extent_buffer(reloc_eb);
4009out:
4010	if (ret < 0) {
4011		btrfs_err_rl(fs_info,
4012			     "failed to account subtree at bytenr %llu: %d",
4013			     subvol_eb->start, ret);
4014		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4015	}
 
 
 
 
4016	return ret;
4017}
v6.8
   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	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	 * Lock the cleaner mutex to prevent races with concurrent relocation,
1346	 * because relocation may be building backrefs for blocks of the quota
1347	 * root while we are deleting the root. This is like dropping fs roots
1348	 * of deleted snapshots/subvolumes, we need the same protection.
1349	 *
1350	 * This also prevents races between concurrent tasks trying to disable
1351	 * quotas, because we will unlock and relock qgroup_ioctl_lock across
1352	 * BTRFS_FS_QUOTA_ENABLED changes.
1353	 */
1354	mutex_lock(&fs_info->cleaner_mutex);
1355
1356	mutex_lock(&fs_info->qgroup_ioctl_lock);
1357	if (!fs_info->quota_root)
1358		goto out;
1359
1360	/*
1361	 * Unlock the qgroup_ioctl_lock mutex before waiting for the rescan worker to
1362	 * complete. Otherwise we can deadlock because btrfs_remove_qgroup() needs
1363	 * to lock that mutex while holding a transaction handle and the rescan
1364	 * worker needs to commit a transaction.
1365	 */
1366	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1367
1368	/*
1369	 * Request qgroup rescan worker to complete and wait for it. This wait
1370	 * must be done before transaction start for quota disable since it may
1371	 * deadlock with transaction by the qgroup rescan worker.
1372	 */
1373	clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1374	btrfs_qgroup_wait_for_completion(fs_info, false);
1375
1376	ret = flush_reservations(fs_info);
1377	if (ret)
1378		goto out_unlock_cleaner;
1379
1380	/*
1381	 * 1 For the root item
1382	 *
1383	 * We should also reserve enough items for the quota tree deletion in
1384	 * btrfs_clean_quota_tree but this is not done.
1385	 *
1386	 * Also, we must always start a transaction without holding the mutex
1387	 * qgroup_ioctl_lock, see btrfs_quota_enable().
1388	 */
1389	trans = btrfs_start_transaction(fs_info->tree_root, 1);
1390
1391	mutex_lock(&fs_info->qgroup_ioctl_lock);
1392	if (IS_ERR(trans)) {
1393		ret = PTR_ERR(trans);
1394		trans = NULL;
1395		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1396		goto out;
1397	}
1398
1399	if (!fs_info->quota_root)
1400		goto out;
1401
1402	spin_lock(&fs_info->qgroup_lock);
1403	quota_root = fs_info->quota_root;
1404	fs_info->quota_root = NULL;
1405	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1406	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE;
1407	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1408	spin_unlock(&fs_info->qgroup_lock);
1409
1410	btrfs_free_qgroup_config(fs_info);
1411
1412	ret = btrfs_clean_quota_tree(trans, quota_root);
1413	if (ret) {
1414		btrfs_abort_transaction(trans, ret);
1415		goto out;
1416	}
1417
1418	ret = btrfs_del_root(trans, &quota_root->root_key);
1419	if (ret) {
1420		btrfs_abort_transaction(trans, ret);
1421		goto out;
1422	}
1423
1424	spin_lock(&fs_info->trans_lock);
1425	list_del(&quota_root->dirty_list);
1426	spin_unlock(&fs_info->trans_lock);
1427
1428	btrfs_tree_lock(quota_root->node);
1429	btrfs_clear_buffer_dirty(trans, quota_root->node);
1430	btrfs_tree_unlock(quota_root->node);
1431	btrfs_free_tree_block(trans, btrfs_root_id(quota_root),
1432			      quota_root->node, 0, 1);
1433
1434	btrfs_put_root(quota_root);
 
 
1435
 
 
1436out:
1437	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1438	if (ret && trans)
1439		btrfs_end_transaction(trans);
1440	else if (trans)
1441		ret = btrfs_commit_transaction(trans);
1442out_unlock_cleaner:
1443	mutex_unlock(&fs_info->cleaner_mutex);
1444
1445	return ret;
1446}
1447
1448static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1449			 struct btrfs_qgroup *qgroup)
1450{
1451	if (list_empty(&qgroup->dirty))
1452		list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1453}
1454
1455static void qgroup_iterator_add(struct list_head *head, struct btrfs_qgroup *qgroup)
1456{
1457	if (!list_empty(&qgroup->iterator))
1458		return;
1459
1460	list_add_tail(&qgroup->iterator, head);
1461}
1462
1463static void qgroup_iterator_clean(struct list_head *head)
1464{
1465	while (!list_empty(head)) {
1466		struct btrfs_qgroup *qgroup;
1467
1468		qgroup = list_first_entry(head, struct btrfs_qgroup, iterator);
1469		list_del_init(&qgroup->iterator);
1470	}
1471}
1472
1473/*
1474 * The easy accounting, we're updating qgroup relationship whose child qgroup
1475 * only has exclusive extents.
1476 *
1477 * In this case, all exclusive extents will also be exclusive for parent, so
1478 * excl/rfer just get added/removed.
1479 *
1480 * So is qgroup reservation space, which should also be added/removed to
1481 * parent.
1482 * Or when child tries to release reservation space, parent will underflow its
1483 * reservation (for relationship adding case).
1484 *
1485 * Caller should hold fs_info->qgroup_lock.
1486 */
1487static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info, u64 ref_root,
 
1488				    struct btrfs_qgroup *src, int sign)
1489{
1490	struct btrfs_qgroup *qgroup;
1491	struct btrfs_qgroup *cur;
1492	LIST_HEAD(qgroup_list);
 
1493	u64 num_bytes = src->excl;
1494	int ret = 0;
1495
1496	qgroup = find_qgroup_rb(fs_info, ref_root);
1497	if (!qgroup)
1498		goto out;
1499
1500	qgroup_iterator_add(&qgroup_list, qgroup);
1501	list_for_each_entry(cur, &qgroup_list, iterator) {
1502		struct btrfs_qgroup_list *glist;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1503
 
 
 
 
1504		qgroup->rfer += sign * num_bytes;
1505		qgroup->rfer_cmpr += sign * num_bytes;
1506
1507		WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1508		qgroup->excl += sign * num_bytes;
1509		qgroup->excl_cmpr += sign * num_bytes;
1510
1511		if (sign > 0)
1512			qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1513		else
1514			qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
 
1515		qgroup_dirty(fs_info, qgroup);
1516
1517		/* Append parent qgroups to @qgroup_list. */
1518		list_for_each_entry(glist, &qgroup->groups, next_group)
1519			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
 
1520	}
1521	ret = 0;
1522out:
1523	qgroup_iterator_clean(&qgroup_list);
1524	return ret;
1525}
1526
1527
1528/*
1529 * Quick path for updating qgroup with only excl refs.
1530 *
1531 * In that case, just update all parent will be enough.
1532 * Or we needs to do a full rescan.
1533 * Caller should also hold fs_info->qgroup_lock.
1534 *
1535 * Return 0 for quick update, return >0 for need to full rescan
1536 * and mark INCONSISTENT flag.
1537 * Return < 0 for other error.
1538 */
1539static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1540				   u64 src, u64 dst, int sign)
 
1541{
1542	struct btrfs_qgroup *qgroup;
1543	int ret = 1;
1544	int err = 0;
1545
1546	qgroup = find_qgroup_rb(fs_info, src);
1547	if (!qgroup)
1548		goto out;
1549	if (qgroup->excl == qgroup->rfer) {
1550		ret = 0;
1551		err = __qgroup_excl_accounting(fs_info, dst, qgroup, sign);
 
1552		if (err < 0) {
1553			ret = err;
1554			goto out;
1555		}
1556	}
1557out:
1558	if (ret)
1559		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1560	return ret;
1561}
1562
1563int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst)
 
1564{
1565	struct btrfs_fs_info *fs_info = trans->fs_info;
 
1566	struct btrfs_qgroup *parent;
1567	struct btrfs_qgroup *member;
1568	struct btrfs_qgroup_list *list;
1569	struct btrfs_qgroup_list *prealloc = NULL;
1570	int ret = 0;
1571
1572	/* Check the level of src and dst first */
1573	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1574		return -EINVAL;
1575
 
 
 
 
1576	mutex_lock(&fs_info->qgroup_ioctl_lock);
1577	if (!fs_info->quota_root) {
1578		ret = -ENOTCONN;
 
1579		goto out;
1580	}
1581	member = find_qgroup_rb(fs_info, src);
1582	parent = find_qgroup_rb(fs_info, dst);
1583	if (!member || !parent) {
1584		ret = -EINVAL;
1585		goto out;
1586	}
1587
1588	/* check if such qgroup relation exist firstly */
1589	list_for_each_entry(list, &member->groups, next_group) {
1590		if (list->group == parent) {
1591			ret = -EEXIST;
1592			goto out;
1593		}
1594	}
1595
1596	prealloc = kzalloc(sizeof(*list), GFP_NOFS);
1597	if (!prealloc) {
1598		ret = -ENOMEM;
1599		goto out;
1600	}
1601	ret = add_qgroup_relation_item(trans, src, dst);
1602	if (ret)
1603		goto out;
1604
1605	ret = add_qgroup_relation_item(trans, dst, src);
1606	if (ret) {
1607		del_qgroup_relation_item(trans, src, dst);
1608		goto out;
1609	}
1610
1611	spin_lock(&fs_info->qgroup_lock);
1612	ret = __add_relation_rb(prealloc, member, parent);
1613	prealloc = NULL;
1614	if (ret < 0) {
1615		spin_unlock(&fs_info->qgroup_lock);
1616		goto out;
1617	}
1618	ret = quick_update_accounting(fs_info, src, dst, 1);
1619	spin_unlock(&fs_info->qgroup_lock);
1620out:
1621	kfree(prealloc);
1622	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
1623	return ret;
1624}
1625
1626static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1627				 u64 dst)
1628{
1629	struct btrfs_fs_info *fs_info = trans->fs_info;
 
1630	struct btrfs_qgroup *parent;
1631	struct btrfs_qgroup *member;
1632	struct btrfs_qgroup_list *list;
 
1633	bool found = false;
1634	int ret = 0;
1635	int ret2;
1636
1637	if (!fs_info->quota_root) {
1638		ret = -ENOTCONN;
 
 
 
 
 
1639		goto out;
1640	}
1641
1642	member = find_qgroup_rb(fs_info, src);
1643	parent = find_qgroup_rb(fs_info, dst);
1644	/*
1645	 * The parent/member pair doesn't exist, then try to delete the dead
1646	 * relation items only.
1647	 */
1648	if (!member || !parent)
1649		goto delete_item;
1650
1651	/* check if such qgroup relation exist firstly */
1652	list_for_each_entry(list, &member->groups, next_group) {
1653		if (list->group == parent) {
1654			found = true;
1655			break;
1656		}
1657	}
1658
1659delete_item:
1660	ret = del_qgroup_relation_item(trans, src, dst);
1661	if (ret < 0 && ret != -ENOENT)
1662		goto out;
1663	ret2 = del_qgroup_relation_item(trans, dst, src);
1664	if (ret2 < 0 && ret2 != -ENOENT)
1665		goto out;
1666
1667	/* At least one deletion succeeded, return 0 */
1668	if (!ret || !ret2)
1669		ret = 0;
1670
1671	if (found) {
1672		spin_lock(&fs_info->qgroup_lock);
1673		del_relation_rb(fs_info, src, dst);
1674		ret = quick_update_accounting(fs_info, src, dst, -1);
1675		spin_unlock(&fs_info->qgroup_lock);
1676	}
1677out:
 
1678	return ret;
1679}
1680
1681int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1682			      u64 dst)
1683{
1684	struct btrfs_fs_info *fs_info = trans->fs_info;
1685	int ret = 0;
1686
1687	mutex_lock(&fs_info->qgroup_ioctl_lock);
1688	ret = __del_qgroup_relation(trans, src, dst);
1689	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1690
1691	return ret;
1692}
1693
1694int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1695{
1696	struct btrfs_fs_info *fs_info = trans->fs_info;
1697	struct btrfs_root *quota_root;
1698	struct btrfs_qgroup *qgroup;
1699	struct btrfs_qgroup *prealloc = NULL;
1700	int ret = 0;
1701
1702	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED)
1703		return 0;
1704
1705	mutex_lock(&fs_info->qgroup_ioctl_lock);
1706	if (!fs_info->quota_root) {
1707		ret = -ENOTCONN;
 
1708		goto out;
1709	}
1710	quota_root = fs_info->quota_root;
1711	qgroup = find_qgroup_rb(fs_info, qgroupid);
1712	if (qgroup) {
1713		ret = -EEXIST;
1714		goto out;
1715	}
1716
1717	prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
1718	if (!prealloc) {
1719		ret = -ENOMEM;
1720		goto out;
1721	}
1722
1723	ret = add_qgroup_item(trans, quota_root, qgroupid);
1724	if (ret)
1725		goto out;
1726
1727	spin_lock(&fs_info->qgroup_lock);
1728	qgroup = add_qgroup_rb(fs_info, prealloc, qgroupid);
1729	spin_unlock(&fs_info->qgroup_lock);
1730	prealloc = NULL;
1731
1732	ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
 
1733out:
1734	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1735	kfree(prealloc);
1736	return ret;
1737}
1738
1739static bool qgroup_has_usage(struct btrfs_qgroup *qgroup)
1740{
1741	return (qgroup->rfer > 0 || qgroup->rfer_cmpr > 0 ||
1742		qgroup->excl > 0 || qgroup->excl_cmpr > 0 ||
1743		qgroup->rsv.values[BTRFS_QGROUP_RSV_DATA] > 0 ||
1744		qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC] > 0 ||
1745		qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > 0);
1746}
1747
1748int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
1749{
1750	struct btrfs_fs_info *fs_info = trans->fs_info;
 
1751	struct btrfs_qgroup *qgroup;
1752	struct btrfs_qgroup_list *list;
1753	int ret = 0;
1754
1755	mutex_lock(&fs_info->qgroup_ioctl_lock);
1756	if (!fs_info->quota_root) {
1757		ret = -ENOTCONN;
 
1758		goto out;
1759	}
1760
1761	qgroup = find_qgroup_rb(fs_info, qgroupid);
1762	if (!qgroup) {
1763		ret = -ENOENT;
1764		goto out;
1765	}
1766
1767	if (is_fstree(qgroupid) && qgroup_has_usage(qgroup)) {
1768		ret = -EBUSY;
1769		goto out;
1770	}
1771
1772	/* Check if there are no children of this qgroup */
1773	if (!list_empty(&qgroup->members)) {
1774		ret = -EBUSY;
1775		goto out;
1776	}
1777
1778	ret = del_qgroup_item(trans, qgroupid);
1779	if (ret && ret != -ENOENT)
1780		goto out;
1781
1782	while (!list_empty(&qgroup->groups)) {
1783		list = list_first_entry(&qgroup->groups,
1784					struct btrfs_qgroup_list, next_group);
1785		ret = __del_qgroup_relation(trans, qgroupid,
1786					    list->group->qgroupid);
1787		if (ret)
1788			goto out;
1789	}
1790
1791	spin_lock(&fs_info->qgroup_lock);
1792	del_qgroup_rb(fs_info, qgroupid);
1793	spin_unlock(&fs_info->qgroup_lock);
1794
1795	/*
1796	 * Remove the qgroup from sysfs now without holding the qgroup_lock
1797	 * spinlock, since the sysfs_remove_group() function needs to take
1798	 * the mutex kernfs_mutex through kernfs_remove_by_name_ns().
1799	 */
1800	btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1801	kfree(qgroup);
1802out:
1803	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1804	return ret;
1805}
1806
1807int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
1808		       struct btrfs_qgroup_limit *limit)
1809{
1810	struct btrfs_fs_info *fs_info = trans->fs_info;
 
1811	struct btrfs_qgroup *qgroup;
1812	int ret = 0;
1813	/* Sometimes we would want to clear the limit on this qgroup.
1814	 * To meet this requirement, we treat the -1 as a special value
1815	 * which tell kernel to clear the limit on this qgroup.
1816	 */
1817	const u64 CLEAR_VALUE = -1;
1818
1819	mutex_lock(&fs_info->qgroup_ioctl_lock);
1820	if (!fs_info->quota_root) {
1821		ret = -ENOTCONN;
 
1822		goto out;
1823	}
1824
1825	qgroup = find_qgroup_rb(fs_info, qgroupid);
1826	if (!qgroup) {
1827		ret = -ENOENT;
1828		goto out;
1829	}
1830
1831	spin_lock(&fs_info->qgroup_lock);
1832	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1833		if (limit->max_rfer == CLEAR_VALUE) {
1834			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1835			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1836			qgroup->max_rfer = 0;
1837		} else {
1838			qgroup->max_rfer = limit->max_rfer;
1839		}
1840	}
1841	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1842		if (limit->max_excl == CLEAR_VALUE) {
1843			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1844			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1845			qgroup->max_excl = 0;
1846		} else {
1847			qgroup->max_excl = limit->max_excl;
1848		}
1849	}
1850	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1851		if (limit->rsv_rfer == CLEAR_VALUE) {
1852			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1853			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1854			qgroup->rsv_rfer = 0;
1855		} else {
1856			qgroup->rsv_rfer = limit->rsv_rfer;
1857		}
1858	}
1859	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1860		if (limit->rsv_excl == CLEAR_VALUE) {
1861			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1862			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1863			qgroup->rsv_excl = 0;
1864		} else {
1865			qgroup->rsv_excl = limit->rsv_excl;
1866		}
1867	}
1868	qgroup->lim_flags |= limit->flags;
1869
1870	spin_unlock(&fs_info->qgroup_lock);
1871
1872	ret = update_qgroup_limit_item(trans, qgroup);
1873	if (ret) {
1874		qgroup_mark_inconsistent(fs_info);
1875		btrfs_info(fs_info, "unable to update quota limit for %llu",
1876		       qgroupid);
1877	}
1878
1879out:
1880	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1881	return ret;
1882}
1883
1884/*
1885 * Inform qgroup to trace one dirty extent, its info is recorded in @record.
1886 * So qgroup can account it at transaction committing time.
1887 *
1888 * No lock version, caller must acquire delayed ref lock and allocated memory,
1889 * then call btrfs_qgroup_trace_extent_post() after exiting lock context.
1890 *
1891 * Return 0 for success insert
1892 * Return >0 for existing record, caller can free @record safely.
1893 * Error is not possible
1894 */
1895int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1896				struct btrfs_delayed_ref_root *delayed_refs,
1897				struct btrfs_qgroup_extent_record *record)
1898{
1899	struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1900	struct rb_node *parent_node = NULL;
1901	struct btrfs_qgroup_extent_record *entry;
1902	u64 bytenr = record->bytenr;
1903
1904	if (!btrfs_qgroup_full_accounting(fs_info))
1905		return 1;
1906
1907	lockdep_assert_held(&delayed_refs->lock);
1908	trace_btrfs_qgroup_trace_extent(fs_info, record);
1909
1910	while (*p) {
1911		parent_node = *p;
1912		entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1913				 node);
1914		if (bytenr < entry->bytenr) {
1915			p = &(*p)->rb_left;
1916		} else if (bytenr > entry->bytenr) {
1917			p = &(*p)->rb_right;
1918		} else {
1919			if (record->data_rsv && !entry->data_rsv) {
1920				entry->data_rsv = record->data_rsv;
1921				entry->data_rsv_refroot =
1922					record->data_rsv_refroot;
1923			}
1924			return 1;
1925		}
1926	}
1927
1928	rb_link_node(&record->node, parent_node, p);
1929	rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1930	return 0;
1931}
1932
1933/*
1934 * Post handler after qgroup_trace_extent_nolock().
1935 *
1936 * NOTE: Current qgroup does the expensive backref walk at transaction
1937 * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming
1938 * new transaction.
1939 * This is designed to allow btrfs_find_all_roots() to get correct new_roots
1940 * result.
1941 *
1942 * However for old_roots there is no need to do backref walk at that time,
1943 * since we search commit roots to walk backref and result will always be
1944 * correct.
1945 *
1946 * Due to the nature of no lock version, we can't do backref there.
1947 * So we must call btrfs_qgroup_trace_extent_post() after exiting
1948 * spinlock context.
1949 *
1950 * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result
1951 * using current root, then we can move all expensive backref walk out of
1952 * transaction committing, but not now as qgroup accounting will be wrong again.
1953 */
1954int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans,
1955				   struct btrfs_qgroup_extent_record *qrecord)
1956{
1957	struct btrfs_backref_walk_ctx ctx = { 0 };
 
1958	int ret;
1959
1960	if (!btrfs_qgroup_full_accounting(trans->fs_info))
1961		return 0;
1962	/*
1963	 * We are always called in a context where we are already holding a
1964	 * transaction handle. Often we are called when adding a data delayed
1965	 * reference from btrfs_truncate_inode_items() (truncating or unlinking),
1966	 * in which case we will be holding a write lock on extent buffer from a
1967	 * subvolume tree. In this case we can't allow btrfs_find_all_roots() to
1968	 * acquire fs_info->commit_root_sem, because that is a higher level lock
1969	 * that must be acquired before locking any extent buffers.
1970	 *
1971	 * So we want btrfs_find_all_roots() to not acquire the commit_root_sem
1972	 * but we can't pass it a non-NULL transaction handle, because otherwise
1973	 * it would not use commit roots and would lock extent buffers, causing
1974	 * a deadlock if it ends up trying to read lock the same extent buffer
1975	 * that was previously write locked at btrfs_truncate_inode_items().
1976	 *
1977	 * So pass a NULL transaction handle to btrfs_find_all_roots() and
1978	 * explicitly tell it to not acquire the commit_root_sem - if we are
1979	 * holding a transaction handle we don't need its protection.
1980	 */
1981	ASSERT(trans != NULL);
1982
1983	if (trans->fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
1984		return 0;
1985
1986	ctx.bytenr = qrecord->bytenr;
1987	ctx.fs_info = trans->fs_info;
1988
1989	ret = btrfs_find_all_roots(&ctx, true);
1990	if (ret < 0) {
1991		qgroup_mark_inconsistent(trans->fs_info);
1992		btrfs_warn(trans->fs_info,
1993"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1994			ret);
1995		return 0;
1996	}
1997
1998	/*
1999	 * Here we don't need to get the lock of
2000	 * trans->transaction->delayed_refs, since inserted qrecord won't
2001	 * be deleted, only qrecord->node may be modified (new qrecord insert)
2002	 *
2003	 * So modifying qrecord->old_roots is safe here
2004	 */
2005	qrecord->old_roots = ctx.roots;
2006	return 0;
2007}
2008
2009/*
2010 * Inform qgroup to trace one dirty extent, specified by @bytenr and
2011 * @num_bytes.
2012 * So qgroup can account it at commit trans time.
2013 *
2014 * Better encapsulated version, with memory allocation and backref walk for
2015 * commit roots.
2016 * So this can sleep.
2017 *
2018 * Return 0 if the operation is done.
2019 * Return <0 for error, like memory allocation failure or invalid parameter
2020 * (NULL trans)
2021 */
2022int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2023			      u64 num_bytes)
2024{
2025	struct btrfs_fs_info *fs_info = trans->fs_info;
2026	struct btrfs_qgroup_extent_record *record;
2027	struct btrfs_delayed_ref_root *delayed_refs;
2028	int ret;
2029
2030	if (!btrfs_qgroup_full_accounting(fs_info) || bytenr == 0 || num_bytes == 0)
 
2031		return 0;
2032	record = kzalloc(sizeof(*record), GFP_NOFS);
2033	if (!record)
2034		return -ENOMEM;
2035
2036	delayed_refs = &trans->transaction->delayed_refs;
2037	record->bytenr = bytenr;
2038	record->num_bytes = num_bytes;
2039	record->old_roots = NULL;
2040
2041	spin_lock(&delayed_refs->lock);
2042	ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
2043	spin_unlock(&delayed_refs->lock);
2044	if (ret > 0) {
2045		kfree(record);
2046		return 0;
2047	}
2048	return btrfs_qgroup_trace_extent_post(trans, record);
2049}
2050
2051/*
2052 * Inform qgroup to trace all leaf items of data
2053 *
2054 * Return 0 for success
2055 * Return <0 for error(ENOMEM)
2056 */
2057int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
2058				  struct extent_buffer *eb)
2059{
2060	struct btrfs_fs_info *fs_info = trans->fs_info;
2061	int nr = btrfs_header_nritems(eb);
2062	int i, extent_type, ret;
2063	struct btrfs_key key;
2064	struct btrfs_file_extent_item *fi;
2065	u64 bytenr, num_bytes;
2066
2067	/* We can be called directly from walk_up_proc() */
2068	if (!btrfs_qgroup_full_accounting(fs_info))
2069		return 0;
2070
2071	for (i = 0; i < nr; i++) {
2072		btrfs_item_key_to_cpu(eb, &key, i);
2073
2074		if (key.type != BTRFS_EXTENT_DATA_KEY)
2075			continue;
2076
2077		fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
2078		/* filter out non qgroup-accountable extents  */
2079		extent_type = btrfs_file_extent_type(eb, fi);
2080
2081		if (extent_type == BTRFS_FILE_EXTENT_INLINE)
2082			continue;
2083
2084		bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
2085		if (!bytenr)
2086			continue;
2087
2088		num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
2089
2090		ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes);
 
2091		if (ret)
2092			return ret;
2093	}
2094	cond_resched();
2095	return 0;
2096}
2097
2098/*
2099 * Walk up the tree from the bottom, freeing leaves and any interior
2100 * nodes which have had all slots visited. If a node (leaf or
2101 * interior) is freed, the node above it will have it's slot
2102 * incremented. The root node will never be freed.
2103 *
2104 * At the end of this function, we should have a path which has all
2105 * slots incremented to the next position for a search. If we need to
2106 * read a new node it will be NULL and the node above it will have the
2107 * correct slot selected for a later read.
2108 *
2109 * If we increment the root nodes slot counter past the number of
2110 * elements, 1 is returned to signal completion of the search.
2111 */
2112static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
2113{
2114	int level = 0;
2115	int nr, slot;
2116	struct extent_buffer *eb;
2117
2118	if (root_level == 0)
2119		return 1;
2120
2121	while (level <= root_level) {
2122		eb = path->nodes[level];
2123		nr = btrfs_header_nritems(eb);
2124		path->slots[level]++;
2125		slot = path->slots[level];
2126		if (slot >= nr || level == 0) {
2127			/*
2128			 * Don't free the root -  we will detect this
2129			 * condition after our loop and return a
2130			 * positive value for caller to stop walking the tree.
2131			 */
2132			if (level != root_level) {
2133				btrfs_tree_unlock_rw(eb, path->locks[level]);
2134				path->locks[level] = 0;
2135
2136				free_extent_buffer(eb);
2137				path->nodes[level] = NULL;
2138				path->slots[level] = 0;
2139			}
2140		} else {
2141			/*
2142			 * We have a valid slot to walk back down
2143			 * from. Stop here so caller can process these
2144			 * new nodes.
2145			 */
2146			break;
2147		}
2148
2149		level++;
2150	}
2151
2152	eb = path->nodes[root_level];
2153	if (path->slots[root_level] >= btrfs_header_nritems(eb))
2154		return 1;
2155
2156	return 0;
2157}
2158
2159/*
2160 * Helper function to trace a subtree tree block swap.
2161 *
2162 * The swap will happen in highest tree block, but there may be a lot of
2163 * tree blocks involved.
2164 *
2165 * For example:
2166 *  OO = Old tree blocks
2167 *  NN = New tree blocks allocated during balance
2168 *
2169 *           File tree (257)                  Reloc tree for 257
2170 * L2              OO                                NN
2171 *               /    \                            /    \
2172 * L1          OO      OO (a)                    OO      NN (a)
2173 *            / \     / \                       / \     / \
2174 * L0       OO   OO OO   OO                   OO   OO NN   NN
2175 *                  (b)  (c)                          (b)  (c)
2176 *
2177 * When calling qgroup_trace_extent_swap(), we will pass:
2178 * @src_eb = OO(a)
2179 * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
2180 * @dst_level = 0
2181 * @root_level = 1
2182 *
2183 * In that case, qgroup_trace_extent_swap() will search from OO(a) to
2184 * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
2185 *
2186 * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
2187 *
2188 * 1) Tree search from @src_eb
2189 *    It should acts as a simplified btrfs_search_slot().
2190 *    The key for search can be extracted from @dst_path->nodes[dst_level]
2191 *    (first key).
2192 *
2193 * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
2194 *    NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
2195 *    They should be marked during previous (@dst_level = 1) iteration.
2196 *
2197 * 3) Mark file extents in leaves dirty
2198 *    We don't have good way to pick out new file extents only.
2199 *    So we still follow the old method by scanning all file extents in
2200 *    the leave.
2201 *
2202 * This function can free us from keeping two paths, thus later we only need
2203 * to care about how to iterate all new tree blocks in reloc tree.
2204 */
2205static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
2206				    struct extent_buffer *src_eb,
2207				    struct btrfs_path *dst_path,
2208				    int dst_level, int root_level,
2209				    bool trace_leaf)
2210{
2211	struct btrfs_key key;
2212	struct btrfs_path *src_path;
2213	struct btrfs_fs_info *fs_info = trans->fs_info;
2214	u32 nodesize = fs_info->nodesize;
2215	int cur_level = root_level;
2216	int ret;
2217
2218	BUG_ON(dst_level > root_level);
2219	/* Level mismatch */
2220	if (btrfs_header_level(src_eb) != root_level)
2221		return -EINVAL;
2222
2223	src_path = btrfs_alloc_path();
2224	if (!src_path) {
2225		ret = -ENOMEM;
2226		goto out;
2227	}
2228
2229	if (dst_level)
2230		btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2231	else
2232		btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2233
2234	/* For src_path */
2235	atomic_inc(&src_eb->refs);
2236	src_path->nodes[root_level] = src_eb;
2237	src_path->slots[root_level] = dst_path->slots[root_level];
2238	src_path->locks[root_level] = 0;
2239
2240	/* A simplified version of btrfs_search_slot() */
2241	while (cur_level >= dst_level) {
2242		struct btrfs_key src_key;
2243		struct btrfs_key dst_key;
2244
2245		if (src_path->nodes[cur_level] == NULL) {
 
2246			struct extent_buffer *eb;
2247			int parent_slot;
 
 
2248
2249			eb = src_path->nodes[cur_level + 1];
2250			parent_slot = src_path->slots[cur_level + 1];
 
 
 
2251
2252			eb = btrfs_read_node_slot(eb, parent_slot);
 
2253			if (IS_ERR(eb)) {
2254				ret = PTR_ERR(eb);
2255				goto out;
 
 
 
 
2256			}
2257
2258			src_path->nodes[cur_level] = eb;
2259
2260			btrfs_tree_read_lock(eb);
2261			src_path->locks[cur_level] = BTRFS_READ_LOCK;
 
2262		}
2263
2264		src_path->slots[cur_level] = dst_path->slots[cur_level];
2265		if (cur_level) {
2266			btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
2267					&dst_key, dst_path->slots[cur_level]);
2268			btrfs_node_key_to_cpu(src_path->nodes[cur_level],
2269					&src_key, src_path->slots[cur_level]);
2270		} else {
2271			btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
2272					&dst_key, dst_path->slots[cur_level]);
2273			btrfs_item_key_to_cpu(src_path->nodes[cur_level],
2274					&src_key, src_path->slots[cur_level]);
2275		}
2276		/* Content mismatch, something went wrong */
2277		if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
2278			ret = -ENOENT;
2279			goto out;
2280		}
2281		cur_level--;
2282	}
2283
2284	/*
2285	 * Now both @dst_path and @src_path have been populated, record the tree
2286	 * blocks for qgroup accounting.
2287	 */
2288	ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
2289					nodesize);
2290	if (ret < 0)
2291		goto out;
2292	ret = btrfs_qgroup_trace_extent(trans, dst_path->nodes[dst_level]->start,
2293					nodesize);
 
2294	if (ret < 0)
2295		goto out;
2296
2297	/* Record leaf file extents */
2298	if (dst_level == 0 && trace_leaf) {
2299		ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
2300		if (ret < 0)
2301			goto out;
2302		ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
2303	}
2304out:
2305	btrfs_free_path(src_path);
2306	return ret;
2307}
2308
2309/*
2310 * Helper function to do recursive generation-aware depth-first search, to
2311 * locate all new tree blocks in a subtree of reloc tree.
2312 *
2313 * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
2314 *         reloc tree
2315 * L2         NN (a)
2316 *          /    \
2317 * L1    OO        NN (b)
2318 *      /  \      /  \
2319 * L0  OO  OO    OO  NN
2320 *               (c) (d)
2321 * If we pass:
2322 * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
2323 * @cur_level = 1
2324 * @root_level = 1
2325 *
2326 * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
2327 * above tree blocks along with their counter parts in file tree.
2328 * While during search, old tree blocks OO(c) will be skipped as tree block swap
2329 * won't affect OO(c).
2330 */
2331static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
2332					   struct extent_buffer *src_eb,
2333					   struct btrfs_path *dst_path,
2334					   int cur_level, int root_level,
2335					   u64 last_snapshot, bool trace_leaf)
2336{
2337	struct btrfs_fs_info *fs_info = trans->fs_info;
2338	struct extent_buffer *eb;
2339	bool need_cleanup = false;
2340	int ret = 0;
2341	int i;
2342
2343	/* Level sanity check */
2344	if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 ||
2345	    root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 ||
2346	    root_level < cur_level) {
2347		btrfs_err_rl(fs_info,
2348			"%s: bad levels, cur_level=%d root_level=%d",
2349			__func__, cur_level, root_level);
2350		return -EUCLEAN;
2351	}
2352
2353	/* Read the tree block if needed */
2354	if (dst_path->nodes[cur_level] == NULL) {
 
2355		int parent_slot;
2356		u64 child_gen;
 
2357
2358		/*
2359		 * dst_path->nodes[root_level] must be initialized before
2360		 * calling this function.
2361		 */
2362		if (cur_level == root_level) {
2363			btrfs_err_rl(fs_info,
2364	"%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
2365				__func__, root_level, root_level, cur_level);
2366			return -EUCLEAN;
2367		}
2368
2369		/*
2370		 * We need to get child blockptr/gen from parent before we can
2371		 * read it.
2372		  */
2373		eb = dst_path->nodes[cur_level + 1];
2374		parent_slot = dst_path->slots[cur_level + 1];
 
2375		child_gen = btrfs_node_ptr_generation(eb, parent_slot);
 
2376
2377		/* This node is old, no need to trace */
2378		if (child_gen < last_snapshot)
2379			goto out;
2380
2381		eb = btrfs_read_node_slot(eb, parent_slot);
 
2382		if (IS_ERR(eb)) {
2383			ret = PTR_ERR(eb);
2384			goto out;
 
 
 
 
2385		}
2386
2387		dst_path->nodes[cur_level] = eb;
2388		dst_path->slots[cur_level] = 0;
2389
2390		btrfs_tree_read_lock(eb);
2391		dst_path->locks[cur_level] = BTRFS_READ_LOCK;
 
2392		need_cleanup = true;
2393	}
2394
2395	/* Now record this tree block and its counter part for qgroups */
2396	ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
2397				       root_level, trace_leaf);
2398	if (ret < 0)
2399		goto cleanup;
2400
2401	eb = dst_path->nodes[cur_level];
2402
2403	if (cur_level > 0) {
2404		/* Iterate all child tree blocks */
2405		for (i = 0; i < btrfs_header_nritems(eb); i++) {
2406			/* Skip old tree blocks as they won't be swapped */
2407			if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
2408				continue;
2409			dst_path->slots[cur_level] = i;
2410
2411			/* Recursive call (at most 7 times) */
2412			ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
2413					dst_path, cur_level - 1, root_level,
2414					last_snapshot, trace_leaf);
2415			if (ret < 0)
2416				goto cleanup;
2417		}
2418	}
2419
2420cleanup:
2421	if (need_cleanup) {
2422		/* Clean up */
2423		btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2424				     dst_path->locks[cur_level]);
2425		free_extent_buffer(dst_path->nodes[cur_level]);
2426		dst_path->nodes[cur_level] = NULL;
2427		dst_path->slots[cur_level] = 0;
2428		dst_path->locks[cur_level] = 0;
2429	}
2430out:
2431	return ret;
2432}
2433
2434static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2435				struct extent_buffer *src_eb,
2436				struct extent_buffer *dst_eb,
2437				u64 last_snapshot, bool trace_leaf)
2438{
2439	struct btrfs_fs_info *fs_info = trans->fs_info;
2440	struct btrfs_path *dst_path = NULL;
2441	int level;
2442	int ret;
2443
2444	if (!btrfs_qgroup_full_accounting(fs_info))
2445		return 0;
2446
2447	/* Wrong parameter order */
2448	if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) {
2449		btrfs_err_rl(fs_info,
2450		"%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2451			     btrfs_header_generation(src_eb),
2452			     btrfs_header_generation(dst_eb));
2453		return -EUCLEAN;
2454	}
2455
2456	if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2457		ret = -EIO;
2458		goto out;
2459	}
2460
2461	level = btrfs_header_level(dst_eb);
2462	dst_path = btrfs_alloc_path();
2463	if (!dst_path) {
2464		ret = -ENOMEM;
2465		goto out;
2466	}
2467	/* For dst_path */
2468	atomic_inc(&dst_eb->refs);
2469	dst_path->nodes[level] = dst_eb;
2470	dst_path->slots[level] = 0;
2471	dst_path->locks[level] = 0;
2472
2473	/* Do the generation aware breadth-first search */
2474	ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2475					      level, last_snapshot, trace_leaf);
2476	if (ret < 0)
2477		goto out;
2478	ret = 0;
2479
2480out:
2481	btrfs_free_path(dst_path);
2482	if (ret < 0)
2483		qgroup_mark_inconsistent(fs_info);
2484	return ret;
2485}
2486
2487/*
2488 * Inform qgroup to trace a whole subtree, including all its child tree
2489 * blocks and data.
2490 * The root tree block is specified by @root_eb.
2491 *
2492 * Normally used by relocation(tree block swap) and subvolume deletion.
2493 *
2494 * Return 0 for success
2495 * Return <0 for error(ENOMEM or tree search error)
2496 */
2497int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
2498			       struct extent_buffer *root_eb,
2499			       u64 root_gen, int root_level)
2500{
2501	struct btrfs_fs_info *fs_info = trans->fs_info;
2502	int ret = 0;
2503	int level;
2504	u8 drop_subptree_thres;
2505	struct extent_buffer *eb = root_eb;
2506	struct btrfs_path *path = NULL;
2507
2508	BUG_ON(root_level < 0 || root_level >= BTRFS_MAX_LEVEL);
2509	BUG_ON(root_eb == NULL);
2510
2511	if (!btrfs_qgroup_full_accounting(fs_info))
2512		return 0;
2513
2514	spin_lock(&fs_info->qgroup_lock);
2515	drop_subptree_thres = fs_info->qgroup_drop_subtree_thres;
2516	spin_unlock(&fs_info->qgroup_lock);
2517
2518	/*
2519	 * This function only gets called for snapshot drop, if we hit a high
2520	 * node here, it means we are going to change ownership for quite a lot
2521	 * of extents, which will greatly slow down btrfs_commit_transaction().
2522	 *
2523	 * So here if we find a high tree here, we just skip the accounting and
2524	 * mark qgroup inconsistent.
2525	 */
2526	if (root_level >= drop_subptree_thres) {
2527		qgroup_mark_inconsistent(fs_info);
2528		return 0;
2529	}
2530
2531	if (!extent_buffer_uptodate(root_eb)) {
2532		struct btrfs_tree_parent_check check = {
2533			.has_first_key = false,
2534			.transid = root_gen,
2535			.level = root_level
2536		};
2537
2538		ret = btrfs_read_extent_buffer(root_eb, &check);
2539		if (ret)
2540			goto out;
2541	}
2542
2543	if (root_level == 0) {
2544		ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2545		goto out;
2546	}
2547
2548	path = btrfs_alloc_path();
2549	if (!path)
2550		return -ENOMEM;
2551
2552	/*
2553	 * Walk down the tree.  Missing extent blocks are filled in as
2554	 * we go. Metadata is accounted every time we read a new
2555	 * extent block.
2556	 *
2557	 * When we reach a leaf, we account for file extent items in it,
2558	 * walk back up the tree (adjusting slot pointers as we go)
2559	 * and restart the search process.
2560	 */
2561	atomic_inc(&root_eb->refs);	/* For path */
2562	path->nodes[root_level] = root_eb;
2563	path->slots[root_level] = 0;
2564	path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2565walk_down:
2566	level = root_level;
2567	while (level >= 0) {
2568		if (path->nodes[level] == NULL) {
 
2569			int parent_slot;
 
2570			u64 child_bytenr;
2571
2572			/*
2573			 * We need to get child blockptr from parent before we
2574			 * can read it.
2575			  */
2576			eb = path->nodes[level + 1];
2577			parent_slot = path->slots[level + 1];
2578			child_bytenr = btrfs_node_blockptr(eb, parent_slot);
 
 
2579
2580			eb = btrfs_read_node_slot(eb, parent_slot);
 
2581			if (IS_ERR(eb)) {
2582				ret = PTR_ERR(eb);
2583				goto out;
 
 
 
 
2584			}
2585
2586			path->nodes[level] = eb;
2587			path->slots[level] = 0;
2588
2589			btrfs_tree_read_lock(eb);
2590			path->locks[level] = BTRFS_READ_LOCK;
 
2591
2592			ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2593							fs_info->nodesize);
 
2594			if (ret)
2595				goto out;
2596		}
2597
2598		if (level == 0) {
2599			ret = btrfs_qgroup_trace_leaf_items(trans,
2600							    path->nodes[level]);
2601			if (ret)
2602				goto out;
2603
2604			/* Nonzero return here means we completed our search */
2605			ret = adjust_slots_upwards(path, root_level);
2606			if (ret)
2607				break;
2608
2609			/* Restart search with new slots */
2610			goto walk_down;
2611		}
2612
2613		level--;
2614	}
2615
2616	ret = 0;
2617out:
2618	btrfs_free_path(path);
2619
2620	return ret;
2621}
2622
2623static void qgroup_iterator_nested_add(struct list_head *head, struct btrfs_qgroup *qgroup)
2624{
2625	if (!list_empty(&qgroup->nested_iterator))
2626		return;
2627
2628	list_add_tail(&qgroup->nested_iterator, head);
2629}
2630
2631static void qgroup_iterator_nested_clean(struct list_head *head)
2632{
2633	while (!list_empty(head)) {
2634		struct btrfs_qgroup *qgroup;
2635
2636		qgroup = list_first_entry(head, struct btrfs_qgroup, nested_iterator);
2637		list_del_init(&qgroup->nested_iterator);
2638	}
2639}
2640
2641#define UPDATE_NEW	0
2642#define UPDATE_OLD	1
2643/*
2644 * Walk all of the roots that points to the bytenr and adjust their refcnts.
2645 */
2646static void qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2647				 struct ulist *roots, struct list_head *qgroups,
2648				 u64 seq, int update_old)
2649{
2650	struct ulist_node *unode;
2651	struct ulist_iterator uiter;
 
 
2652	struct btrfs_qgroup *qg;
 
2653
2654	if (!roots)
2655		return;
2656	ULIST_ITER_INIT(&uiter);
2657	while ((unode = ulist_next(roots, &uiter))) {
2658		LIST_HEAD(tmp);
2659
2660		qg = find_qgroup_rb(fs_info, unode->val);
2661		if (!qg)
2662			continue;
2663
2664		qgroup_iterator_nested_add(qgroups, qg);
2665		qgroup_iterator_add(&tmp, qg);
2666		list_for_each_entry(qg, &tmp, iterator) {
 
 
 
 
 
 
 
2667			struct btrfs_qgroup_list *glist;
2668
 
2669			if (update_old)
2670				btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2671			else
2672				btrfs_qgroup_update_new_refcnt(qg, seq, 1);
2673
2674			list_for_each_entry(glist, &qg->groups, next_group) {
2675				qgroup_iterator_nested_add(qgroups, glist->group);
2676				qgroup_iterator_add(&tmp, glist->group);
 
 
 
 
 
 
 
 
2677			}
2678		}
2679		qgroup_iterator_clean(&tmp);
2680	}
 
2681}
2682
2683/*
2684 * Update qgroup rfer/excl counters.
2685 * Rfer update is easy, codes can explain themselves.
2686 *
2687 * Excl update is tricky, the update is split into 2 parts.
2688 * Part 1: Possible exclusive <-> sharing detect:
2689 *	|	A	|	!A	|
2690 *  -------------------------------------
2691 *  B	|	*	|	-	|
2692 *  -------------------------------------
2693 *  !B	|	+	|	**	|
2694 *  -------------------------------------
2695 *
2696 * Conditions:
2697 * A:	cur_old_roots < nr_old_roots	(not exclusive before)
2698 * !A:	cur_old_roots == nr_old_roots	(possible exclusive before)
2699 * B:	cur_new_roots < nr_new_roots	(not exclusive now)
2700 * !B:	cur_new_roots == nr_new_roots	(possible exclusive now)
2701 *
2702 * Results:
2703 * +: Possible sharing -> exclusive	-: Possible exclusive -> sharing
2704 * *: Definitely not changed.		**: Possible unchanged.
2705 *
2706 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2707 *
2708 * To make the logic clear, we first use condition A and B to split
2709 * combination into 4 results.
2710 *
2711 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2712 * only on variant maybe 0.
2713 *
2714 * Lastly, check result **, since there are 2 variants maybe 0, split them
2715 * again(2x2).
2716 * But this time we don't need to consider other things, the codes and logic
2717 * is easy to understand now.
2718 */
2719static void qgroup_update_counters(struct btrfs_fs_info *fs_info,
2720				   struct list_head *qgroups, u64 nr_old_roots,
2721				   u64 nr_new_roots, u64 num_bytes, u64 seq)
 
 
2722{
 
 
2723	struct btrfs_qgroup *qg;
 
2724
2725	list_for_each_entry(qg, qgroups, nested_iterator) {
2726		u64 cur_new_count, cur_old_count;
2727		bool dirty = false;
2728
 
2729		cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2730		cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2731
2732		trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2733					     cur_new_count);
2734
2735		/* Rfer update part */
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		if (cur_old_count > 0 && cur_new_count == 0) {
2742			qg->rfer -= num_bytes;
2743			qg->rfer_cmpr -= num_bytes;
2744			dirty = true;
2745		}
2746
2747		/* Excl update part */
2748		/* Exclusive/none -> shared case */
2749		if (cur_old_count == nr_old_roots &&
2750		    cur_new_count < nr_new_roots) {
2751			/* Exclusive -> shared */
2752			if (cur_old_count != 0) {
2753				qg->excl -= num_bytes;
2754				qg->excl_cmpr -= num_bytes;
2755				dirty = true;
2756			}
2757		}
2758
2759		/* Shared -> exclusive/none case */
2760		if (cur_old_count < nr_old_roots &&
2761		    cur_new_count == nr_new_roots) {
2762			/* Shared->exclusive */
2763			if (cur_new_count != 0) {
2764				qg->excl += num_bytes;
2765				qg->excl_cmpr += num_bytes;
2766				dirty = true;
2767			}
2768		}
2769
2770		/* Exclusive/none -> exclusive/none case */
2771		if (cur_old_count == nr_old_roots &&
2772		    cur_new_count == nr_new_roots) {
2773			if (cur_old_count == 0) {
2774				/* None -> exclusive/none */
2775
2776				if (cur_new_count != 0) {
2777					/* None -> exclusive */
2778					qg->excl += num_bytes;
2779					qg->excl_cmpr += num_bytes;
2780					dirty = true;
2781				}
2782				/* None -> none, nothing changed */
2783			} else {
2784				/* Exclusive -> exclusive/none */
2785
2786				if (cur_new_count == 0) {
2787					/* Exclusive -> none */
2788					qg->excl -= num_bytes;
2789					qg->excl_cmpr -= num_bytes;
2790					dirty = true;
2791				}
2792				/* Exclusive -> exclusive, nothing changed */
2793			}
2794		}
2795
2796		if (dirty)
2797			qgroup_dirty(fs_info, qg);
2798	}
 
2799}
2800
2801/*
2802 * Check if the @roots potentially is a list of fs tree roots
2803 *
2804 * Return 0 for definitely not a fs/subvol tree roots ulist
2805 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2806 *          one as well)
2807 */
2808static int maybe_fs_roots(struct ulist *roots)
2809{
2810	struct ulist_node *unode;
2811	struct ulist_iterator uiter;
2812
2813	/* Empty one, still possible for fs roots */
2814	if (!roots || roots->nnodes == 0)
2815		return 1;
2816
2817	ULIST_ITER_INIT(&uiter);
2818	unode = ulist_next(roots, &uiter);
2819	if (!unode)
2820		return 1;
2821
2822	/*
2823	 * If it contains fs tree roots, then it must belong to fs/subvol
2824	 * trees.
2825	 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2826	 */
2827	return is_fstree(unode->val);
2828}
2829
2830int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2831				u64 num_bytes, struct ulist *old_roots,
2832				struct ulist *new_roots)
2833{
2834	struct btrfs_fs_info *fs_info = trans->fs_info;
2835	LIST_HEAD(qgroups);
 
2836	u64 seq;
2837	u64 nr_new_roots = 0;
2838	u64 nr_old_roots = 0;
2839	int ret = 0;
2840
2841	/*
2842	 * If quotas get disabled meanwhile, the resources need to be freed and
2843	 * we can't just exit here.
2844	 */
2845	if (!btrfs_qgroup_full_accounting(fs_info) ||
2846	    fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
2847		goto out_free;
2848
2849	if (new_roots) {
2850		if (!maybe_fs_roots(new_roots))
2851			goto out_free;
2852		nr_new_roots = new_roots->nnodes;
2853	}
2854	if (old_roots) {
2855		if (!maybe_fs_roots(old_roots))
2856			goto out_free;
2857		nr_old_roots = old_roots->nnodes;
2858	}
2859
2860	/* Quick exit, either not fs tree roots, or won't affect any qgroup */
2861	if (nr_old_roots == 0 && nr_new_roots == 0)
2862		goto out_free;
2863
2864	BUG_ON(!fs_info->quota_root);
2865
2866	trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2867					num_bytes, nr_old_roots, nr_new_roots);
2868
 
 
 
 
 
 
 
 
 
 
 
2869	mutex_lock(&fs_info->qgroup_rescan_lock);
2870	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2871		if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2872			mutex_unlock(&fs_info->qgroup_rescan_lock);
2873			ret = 0;
2874			goto out_free;
2875		}
2876	}
2877	mutex_unlock(&fs_info->qgroup_rescan_lock);
2878
2879	spin_lock(&fs_info->qgroup_lock);
2880	seq = fs_info->qgroup_seq;
2881
2882	/* Update old refcnts using old_roots */
2883	qgroup_update_refcnt(fs_info, old_roots, &qgroups, seq, UPDATE_OLD);
 
 
 
2884
2885	/* Update new refcnts using new_roots */
2886	qgroup_update_refcnt(fs_info, new_roots, &qgroups, seq, UPDATE_NEW);
 
 
 
2887
2888	qgroup_update_counters(fs_info, &qgroups, nr_old_roots, nr_new_roots,
2889			       num_bytes, seq);
2890
2891	/*
2892	 * We're done using the iterator, release all its qgroups while holding
2893	 * fs_info->qgroup_lock so that we don't race with btrfs_remove_qgroup()
2894	 * and trigger use-after-free accesses to qgroups.
2895	 */
2896	qgroup_iterator_nested_clean(&qgroups);
2897
2898	/*
2899	 * Bump qgroup_seq to avoid seq overlap
2900	 */
2901	fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
 
2902	spin_unlock(&fs_info->qgroup_lock);
2903out_free:
 
 
2904	ulist_free(old_roots);
2905	ulist_free(new_roots);
2906	return ret;
2907}
2908
2909int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2910{
2911	struct btrfs_fs_info *fs_info = trans->fs_info;
2912	struct btrfs_qgroup_extent_record *record;
2913	struct btrfs_delayed_ref_root *delayed_refs;
2914	struct ulist *new_roots = NULL;
2915	struct rb_node *node;
2916	u64 num_dirty_extents = 0;
2917	u64 qgroup_to_skip;
2918	int ret = 0;
2919
2920	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
2921		return 0;
2922
2923	delayed_refs = &trans->transaction->delayed_refs;
2924	qgroup_to_skip = delayed_refs->qgroup_to_skip;
2925	while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2926		record = rb_entry(node, struct btrfs_qgroup_extent_record,
2927				  node);
2928
2929		num_dirty_extents++;
2930		trace_btrfs_qgroup_account_extents(fs_info, record);
2931
2932		if (!ret && !(fs_info->qgroup_flags &
2933			      BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)) {
2934			struct btrfs_backref_walk_ctx ctx = { 0 };
2935
2936			ctx.bytenr = record->bytenr;
2937			ctx.fs_info = fs_info;
2938
2939			/*
2940			 * Old roots should be searched when inserting qgroup
2941			 * extent record.
2942			 *
2943			 * But for INCONSISTENT (NO_ACCOUNTING) -> rescan case,
2944			 * we may have some record inserted during
2945			 * NO_ACCOUNTING (thus no old_roots populated), but
2946			 * later we start rescan, which clears NO_ACCOUNTING,
2947			 * leaving some inserted records without old_roots
2948			 * populated.
2949			 *
2950			 * Those cases are rare and should not cause too much
2951			 * time spent during commit_transaction().
2952			 */
2953			if (!record->old_roots) {
2954				/* Search commit root to find old_roots */
2955				ret = btrfs_find_all_roots(&ctx, false);
 
 
2956				if (ret < 0)
2957					goto cleanup;
2958				record->old_roots = ctx.roots;
2959				ctx.roots = NULL;
2960			}
2961
2962			/* Free the reserved data space */
2963			btrfs_qgroup_free_refroot(fs_info,
2964					record->data_rsv_refroot,
2965					record->data_rsv,
2966					BTRFS_QGROUP_RSV_DATA);
2967			/*
2968			 * Use BTRFS_SEQ_LAST as time_seq to do special search,
2969			 * which doesn't lock tree or delayed_refs and search
2970			 * current root. It's safe inside commit_transaction().
2971			 */
2972			ctx.trans = trans;
2973			ctx.time_seq = BTRFS_SEQ_LAST;
2974			ret = btrfs_find_all_roots(&ctx, false);
2975			if (ret < 0)
2976				goto cleanup;
2977			new_roots = ctx.roots;
2978			if (qgroup_to_skip) {
2979				ulist_del(new_roots, qgroup_to_skip, 0);
2980				ulist_del(record->old_roots, qgroup_to_skip,
2981					  0);
2982			}
2983			ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2984							  record->num_bytes,
2985							  record->old_roots,
2986							  new_roots);
2987			record->old_roots = NULL;
2988			new_roots = NULL;
2989		}
2990cleanup:
2991		ulist_free(record->old_roots);
2992		ulist_free(new_roots);
2993		new_roots = NULL;
2994		rb_erase(node, &delayed_refs->dirty_extent_root);
2995		kfree(record);
2996
2997	}
2998	trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2999				       num_dirty_extents);
3000	return ret;
3001}
3002
3003/*
3004 * Writes all changed qgroups to disk.
3005 * Called by the transaction commit path and the qgroup assign ioctl.
3006 */
3007int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
3008{
3009	struct btrfs_fs_info *fs_info = trans->fs_info;
 
3010	int ret = 0;
3011
3012	/*
3013	 * In case we are called from the qgroup assign ioctl, assert that we
3014	 * are holding the qgroup_ioctl_lock, otherwise we can race with a quota
3015	 * disable operation (ioctl) and access a freed quota root.
3016	 */
3017	if (trans->transaction->state != TRANS_STATE_COMMIT_DOING)
3018		lockdep_assert_held(&fs_info->qgroup_ioctl_lock);
3019
3020	if (!fs_info->quota_root)
3021		return ret;
3022
3023	spin_lock(&fs_info->qgroup_lock);
3024	while (!list_empty(&fs_info->dirty_qgroups)) {
3025		struct btrfs_qgroup *qgroup;
3026		qgroup = list_first_entry(&fs_info->dirty_qgroups,
3027					  struct btrfs_qgroup, dirty);
3028		list_del_init(&qgroup->dirty);
3029		spin_unlock(&fs_info->qgroup_lock);
3030		ret = update_qgroup_info_item(trans, qgroup);
3031		if (ret)
3032			qgroup_mark_inconsistent(fs_info);
 
3033		ret = update_qgroup_limit_item(trans, qgroup);
3034		if (ret)
3035			qgroup_mark_inconsistent(fs_info);
 
3036		spin_lock(&fs_info->qgroup_lock);
3037	}
3038	if (btrfs_qgroup_enabled(fs_info))
3039		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
3040	else
3041		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
3042	spin_unlock(&fs_info->qgroup_lock);
3043
3044	ret = update_qgroup_status_item(trans);
3045	if (ret)
3046		qgroup_mark_inconsistent(fs_info);
3047
3048	return ret;
3049}
3050
3051static int qgroup_auto_inherit(struct btrfs_fs_info *fs_info,
3052			       u64 inode_rootid,
3053			       struct btrfs_qgroup_inherit **inherit)
3054{
3055	int i = 0;
3056	u64 num_qgroups = 0;
3057	struct btrfs_qgroup *inode_qg;
3058	struct btrfs_qgroup_list *qg_list;
3059	struct btrfs_qgroup_inherit *res;
3060	size_t struct_sz;
3061	u64 *qgids;
3062
3063	if (*inherit)
3064		return -EEXIST;
3065
3066	inode_qg = find_qgroup_rb(fs_info, inode_rootid);
3067	if (!inode_qg)
3068		return -ENOENT;
3069
3070	num_qgroups = list_count_nodes(&inode_qg->groups);
3071
3072	if (!num_qgroups)
3073		return 0;
3074
3075	struct_sz = struct_size(res, qgroups, num_qgroups);
3076	if (struct_sz == SIZE_MAX)
3077		return -ERANGE;
3078
3079	res = kzalloc(struct_sz, GFP_NOFS);
3080	if (!res)
3081		return -ENOMEM;
3082	res->num_qgroups = num_qgroups;
3083	qgids = res->qgroups;
3084
3085	list_for_each_entry(qg_list, &inode_qg->groups, next_group)
3086		qgids[i] = qg_list->group->qgroupid;
3087
3088	*inherit = res;
3089	return 0;
3090}
3091
3092/*
3093 * Copy the accounting information between qgroups. This is necessary
3094 * when a snapshot or a subvolume is created. Throwing an error will
3095 * cause a transaction abort so we take extra care here to only error
3096 * when a readonly fs is a reasonable outcome.
3097 */
3098int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
3099			 u64 objectid, u64 inode_rootid,
3100			 struct btrfs_qgroup_inherit *inherit)
3101{
3102	int ret = 0;
3103	int i;
3104	u64 *i_qgroups;
3105	bool committing = false;
3106	struct btrfs_fs_info *fs_info = trans->fs_info;
3107	struct btrfs_root *quota_root;
3108	struct btrfs_qgroup *srcgroup;
3109	struct btrfs_qgroup *dstgroup;
3110	struct btrfs_qgroup *prealloc;
3111	struct btrfs_qgroup_list **qlist_prealloc = NULL;
3112	bool free_inherit = false;
3113	bool need_rescan = false;
3114	u32 level_size = 0;
3115	u64 nums;
3116
3117	prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS);
3118	if (!prealloc)
3119		return -ENOMEM;
3120
3121	/*
3122	 * There are only two callers of this function.
3123	 *
3124	 * One in create_subvol() in the ioctl context, which needs to hold
3125	 * the qgroup_ioctl_lock.
3126	 *
3127	 * The other one in create_pending_snapshot() where no other qgroup
3128	 * code can modify the fs as they all need to either start a new trans
3129	 * or hold a trans handler, thus we don't need to hold
3130	 * qgroup_ioctl_lock.
3131	 * This would avoid long and complex lock chain and make lockdep happy.
3132	 */
3133	spin_lock(&fs_info->trans_lock);
3134	if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
3135		committing = true;
3136	spin_unlock(&fs_info->trans_lock);
3137
3138	if (!committing)
3139		mutex_lock(&fs_info->qgroup_ioctl_lock);
3140	if (!btrfs_qgroup_enabled(fs_info))
3141		goto out;
3142
3143	quota_root = fs_info->quota_root;
3144	if (!quota_root) {
3145		ret = -EINVAL;
3146		goto out;
3147	}
3148
3149	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE && !inherit) {
3150		ret = qgroup_auto_inherit(fs_info, inode_rootid, &inherit);
3151		if (ret)
3152			goto out;
3153		free_inherit = true;
3154	}
3155
3156	if (inherit) {
3157		i_qgroups = (u64 *)(inherit + 1);
3158		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
3159		       2 * inherit->num_excl_copies;
3160		for (i = 0; i < nums; ++i) {
3161			srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
3162
3163			/*
3164			 * Zero out invalid groups so we can ignore
3165			 * them later.
3166			 */
3167			if (!srcgroup ||
3168			    ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
3169				*i_qgroups = 0ULL;
3170
3171			++i_qgroups;
3172		}
3173	}
3174
3175	/*
3176	 * create a tracking group for the subvol itself
3177	 */
3178	ret = add_qgroup_item(trans, quota_root, objectid);
3179	if (ret)
3180		goto out;
3181
3182	/*
3183	 * add qgroup to all inherited groups
3184	 */
3185	if (inherit) {
3186		i_qgroups = (u64 *)(inherit + 1);
3187		for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
3188			if (*i_qgroups == 0)
3189				continue;
3190			ret = add_qgroup_relation_item(trans, objectid,
3191						       *i_qgroups);
3192			if (ret && ret != -EEXIST)
3193				goto out;
3194			ret = add_qgroup_relation_item(trans, *i_qgroups,
3195						       objectid);
3196			if (ret && ret != -EEXIST)
3197				goto out;
3198		}
3199		ret = 0;
 
3200
3201		qlist_prealloc = kcalloc(inherit->num_qgroups,
3202					 sizeof(struct btrfs_qgroup_list *),
3203					 GFP_NOFS);
3204		if (!qlist_prealloc) {
3205			ret = -ENOMEM;
3206			goto out;
3207		}
3208		for (int i = 0; i < inherit->num_qgroups; i++) {
3209			qlist_prealloc[i] = kzalloc(sizeof(struct btrfs_qgroup_list),
3210						    GFP_NOFS);
3211			if (!qlist_prealloc[i]) {
3212				ret = -ENOMEM;
3213				goto out;
3214			}
3215		}
3216	}
3217
3218	spin_lock(&fs_info->qgroup_lock);
3219
3220	dstgroup = add_qgroup_rb(fs_info, prealloc, objectid);
3221	prealloc = NULL;
 
 
 
3222
3223	if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
3224		dstgroup->lim_flags = inherit->lim.flags;
3225		dstgroup->max_rfer = inherit->lim.max_rfer;
3226		dstgroup->max_excl = inherit->lim.max_excl;
3227		dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
3228		dstgroup->rsv_excl = inherit->lim.rsv_excl;
3229
3230		qgroup_dirty(fs_info, dstgroup);
 
 
 
 
 
 
 
3231	}
3232
3233	if (srcid && btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL) {
3234		srcgroup = find_qgroup_rb(fs_info, srcid);
3235		if (!srcgroup)
3236			goto unlock;
3237
3238		/*
3239		 * We call inherit after we clone the root in order to make sure
3240		 * our counts don't go crazy, so at this point the only
3241		 * difference between the two roots should be the root node.
3242		 */
3243		level_size = fs_info->nodesize;
3244		dstgroup->rfer = srcgroup->rfer;
3245		dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
3246		dstgroup->excl = level_size;
3247		dstgroup->excl_cmpr = level_size;
3248		srcgroup->excl = level_size;
3249		srcgroup->excl_cmpr = level_size;
3250
3251		/* inherit the limit info */
3252		dstgroup->lim_flags = srcgroup->lim_flags;
3253		dstgroup->max_rfer = srcgroup->max_rfer;
3254		dstgroup->max_excl = srcgroup->max_excl;
3255		dstgroup->rsv_rfer = srcgroup->rsv_rfer;
3256		dstgroup->rsv_excl = srcgroup->rsv_excl;
3257
3258		qgroup_dirty(fs_info, dstgroup);
3259		qgroup_dirty(fs_info, srcgroup);
3260	}
3261
3262	if (!inherit)
3263		goto unlock;
3264
3265	i_qgroups = (u64 *)(inherit + 1);
3266	for (i = 0; i < inherit->num_qgroups; ++i) {
3267		if (*i_qgroups) {
3268			ret = add_relation_rb(fs_info, qlist_prealloc[i], objectid,
3269					      *i_qgroups);
3270			qlist_prealloc[i] = NULL;
3271			if (ret)
3272				goto unlock;
3273		}
3274		++i_qgroups;
3275
3276		/*
3277		 * If we're doing a snapshot, and adding the snapshot to a new
3278		 * qgroup, the numbers are guaranteed to be incorrect.
3279		 */
3280		if (srcid)
3281			need_rescan = true;
3282	}
3283
3284	for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
3285		struct btrfs_qgroup *src;
3286		struct btrfs_qgroup *dst;
3287
3288		if (!i_qgroups[0] || !i_qgroups[1])
3289			continue;
3290
3291		src = find_qgroup_rb(fs_info, i_qgroups[0]);
3292		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3293
3294		if (!src || !dst) {
3295			ret = -EINVAL;
3296			goto unlock;
3297		}
3298
3299		dst->rfer = src->rfer - level_size;
3300		dst->rfer_cmpr = src->rfer_cmpr - level_size;
3301
3302		/* Manually tweaking numbers certainly needs a rescan */
3303		need_rescan = true;
3304	}
3305	for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
3306		struct btrfs_qgroup *src;
3307		struct btrfs_qgroup *dst;
3308
3309		if (!i_qgroups[0] || !i_qgroups[1])
3310			continue;
3311
3312		src = find_qgroup_rb(fs_info, i_qgroups[0]);
3313		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3314
3315		if (!src || !dst) {
3316			ret = -EINVAL;
3317			goto unlock;
3318		}
3319
3320		dst->excl = src->excl + level_size;
3321		dst->excl_cmpr = src->excl_cmpr + level_size;
3322		need_rescan = true;
3323	}
3324
3325unlock:
3326	spin_unlock(&fs_info->qgroup_lock);
3327	if (!ret)
3328		ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup);
3329out:
3330	if (!committing)
3331		mutex_unlock(&fs_info->qgroup_ioctl_lock);
3332	if (need_rescan)
3333		qgroup_mark_inconsistent(fs_info);
3334	if (qlist_prealloc) {
3335		for (int i = 0; i < inherit->num_qgroups; i++)
3336			kfree(qlist_prealloc[i]);
3337		kfree(qlist_prealloc);
3338	}
3339	if (free_inherit)
3340		kfree(inherit);
3341	kfree(prealloc);
3342	return ret;
3343}
3344
3345static bool qgroup_check_limits(const struct btrfs_qgroup *qg, u64 num_bytes)
 
 
 
 
 
 
 
 
 
3346{
 
 
 
3347	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
3348	    qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
3349		return false;
3350
3351	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
3352	    qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
3353		return false;
3354
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3355	return true;
3356}
3357
3358static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
3359			  enum btrfs_qgroup_rsv_type type)
3360{
 
3361	struct btrfs_qgroup *qgroup;
3362	struct btrfs_fs_info *fs_info = root->fs_info;
3363	u64 ref_root = root->root_key.objectid;
3364	int ret = 0;
3365	LIST_HEAD(qgroup_list);
 
3366
3367	if (!is_fstree(ref_root))
3368		return 0;
3369
3370	if (num_bytes == 0)
3371		return 0;
3372
3373	if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
3374	    capable(CAP_SYS_RESOURCE))
3375		enforce = false;
3376
3377	spin_lock(&fs_info->qgroup_lock);
3378	if (!fs_info->quota_root)
 
3379		goto out;
3380
3381	qgroup = find_qgroup_rb(fs_info, ref_root);
3382	if (!qgroup)
3383		goto out;
3384
3385	qgroup_iterator_add(&qgroup_list, qgroup);
3386	list_for_each_entry(qgroup, &qgroup_list, iterator) {
 
 
 
 
 
 
 
 
 
 
3387		struct btrfs_qgroup_list *glist;
3388
3389		if (enforce && !qgroup_check_limits(qgroup, num_bytes)) {
 
 
3390			ret = -EDQUOT;
3391			goto out;
3392		}
3393
3394		list_for_each_entry(glist, &qgroup->groups, next_group)
3395			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
 
 
3396	}
3397
3398	ret = 0;
3399	/*
3400	 * no limits exceeded, now record the reservation into all qgroups
3401	 */
3402	list_for_each_entry(qgroup, &qgroup_list, iterator)
3403		qgroup_rsv_add(fs_info, qgroup, num_bytes, type);
 
 
 
 
 
 
3404
3405out:
3406	qgroup_iterator_clean(&qgroup_list);
3407	spin_unlock(&fs_info->qgroup_lock);
3408	return ret;
3409}
3410
3411/*
3412 * Free @num_bytes of reserved space with @type for qgroup.  (Normally level 0
3413 * qgroup).
3414 *
3415 * Will handle all higher level qgroup too.
3416 *
3417 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
3418 * This special case is only used for META_PERTRANS type.
3419 */
3420void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
3421			       u64 ref_root, u64 num_bytes,
3422			       enum btrfs_qgroup_rsv_type type)
3423{
 
3424	struct btrfs_qgroup *qgroup;
3425	LIST_HEAD(qgroup_list);
 
 
3426
3427	if (!is_fstree(ref_root))
3428		return;
3429
3430	if (num_bytes == 0)
3431		return;
3432
3433	if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
3434		WARN(1, "%s: Invalid type to free", __func__);
3435		return;
3436	}
3437	spin_lock(&fs_info->qgroup_lock);
3438
3439	if (!fs_info->quota_root)
 
3440		goto out;
3441
3442	qgroup = find_qgroup_rb(fs_info, ref_root);
3443	if (!qgroup)
3444		goto out;
3445
3446	if (num_bytes == (u64)-1)
3447		/*
3448		 * We're freeing all pertrans rsv, get reserved value from
3449		 * level 0 qgroup as real num_bytes to free.
3450		 */
3451		num_bytes = qgroup->rsv.values[type];
3452
3453	qgroup_iterator_add(&qgroup_list, qgroup);
3454	list_for_each_entry(qgroup, &qgroup_list, iterator) {
 
 
 
 
 
 
3455		struct btrfs_qgroup_list *glist;
3456
3457		qgroup_rsv_release(fs_info, qgroup, num_bytes, type);
3458		list_for_each_entry(glist, &qgroup->groups, next_group) {
3459			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
 
 
 
 
3460		}
3461	}
 
3462out:
3463	qgroup_iterator_clean(&qgroup_list);
3464	spin_unlock(&fs_info->qgroup_lock);
3465}
3466
3467/*
3468 * Check if the leaf is the last leaf. Which means all node pointers
3469 * are at their last position.
3470 */
3471static bool is_last_leaf(struct btrfs_path *path)
3472{
3473	int i;
3474
3475	for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3476		if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3477			return false;
3478	}
3479	return true;
3480}
3481
3482/*
3483 * returns < 0 on error, 0 when more leafs are to be scanned.
3484 * returns 1 when done.
3485 */
3486static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3487			      struct btrfs_path *path)
3488{
3489	struct btrfs_fs_info *fs_info = trans->fs_info;
3490	struct btrfs_root *extent_root;
3491	struct btrfs_key found;
3492	struct extent_buffer *scratch_leaf = NULL;
 
3493	u64 num_bytes;
3494	bool done;
3495	int slot;
3496	int ret;
3497
3498	if (!btrfs_qgroup_full_accounting(fs_info))
3499		return 1;
3500
3501	mutex_lock(&fs_info->qgroup_rescan_lock);
3502	extent_root = btrfs_extent_root(fs_info,
3503				fs_info->qgroup_rescan_progress.objectid);
3504	ret = btrfs_search_slot_for_read(extent_root,
3505					 &fs_info->qgroup_rescan_progress,
3506					 path, 1, 0);
3507
3508	btrfs_debug(fs_info,
3509		"current progress key (%llu %u %llu), search_slot ret %d",
3510		fs_info->qgroup_rescan_progress.objectid,
3511		fs_info->qgroup_rescan_progress.type,
3512		fs_info->qgroup_rescan_progress.offset, ret);
3513
3514	if (ret) {
3515		/*
3516		 * The rescan is about to end, we will not be scanning any
3517		 * further blocks. We cannot unset the RESCAN flag here, because
3518		 * we want to commit the transaction if everything went well.
3519		 * To make the live accounting work in this phase, we set our
3520		 * scan progress pointer such that every real extent objectid
3521		 * will be smaller.
3522		 */
3523		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3524		btrfs_release_path(path);
3525		mutex_unlock(&fs_info->qgroup_rescan_lock);
3526		return ret;
3527	}
3528	done = is_last_leaf(path);
3529
3530	btrfs_item_key_to_cpu(path->nodes[0], &found,
3531			      btrfs_header_nritems(path->nodes[0]) - 1);
3532	fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3533
3534	scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3535	if (!scratch_leaf) {
3536		ret = -ENOMEM;
3537		mutex_unlock(&fs_info->qgroup_rescan_lock);
3538		goto out;
3539	}
3540	slot = path->slots[0];
3541	btrfs_release_path(path);
3542	mutex_unlock(&fs_info->qgroup_rescan_lock);
3543
3544	for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
3545		struct btrfs_backref_walk_ctx ctx = { 0 };
3546
3547		btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3548		if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3549		    found.type != BTRFS_METADATA_ITEM_KEY)
3550			continue;
3551		if (found.type == BTRFS_METADATA_ITEM_KEY)
3552			num_bytes = fs_info->nodesize;
3553		else
3554			num_bytes = found.offset;
3555
3556		ctx.bytenr = found.objectid;
3557		ctx.fs_info = fs_info;
3558
3559		ret = btrfs_find_all_roots(&ctx, false);
3560		if (ret < 0)
3561			goto out;
3562		/* For rescan, just pass old_roots as NULL */
3563		ret = btrfs_qgroup_account_extent(trans, found.objectid,
3564						  num_bytes, NULL, ctx.roots);
3565		if (ret < 0)
3566			goto out;
3567	}
3568out:
3569	if (scratch_leaf)
3570		free_extent_buffer(scratch_leaf);
3571
3572	if (done && !ret) {
3573		ret = 1;
3574		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3575	}
3576	return ret;
3577}
3578
3579static bool rescan_should_stop(struct btrfs_fs_info *fs_info)
3580{
3581	if (btrfs_fs_closing(fs_info))
3582		return true;
3583	if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
3584		return true;
3585	if (!btrfs_qgroup_enabled(fs_info))
3586		return true;
3587	if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3588		return true;
3589	return false;
3590}
3591
3592static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3593{
3594	struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3595						     qgroup_rescan_work);
3596	struct btrfs_path *path;
3597	struct btrfs_trans_handle *trans = NULL;
3598	int err = -ENOMEM;
3599	int ret = 0;
3600	bool stopped = false;
3601	bool did_leaf_rescans = false;
3602
3603	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE)
3604		return;
3605
3606	path = btrfs_alloc_path();
3607	if (!path)
3608		goto out;
3609	/*
3610	 * Rescan should only search for commit root, and any later difference
3611	 * should be recorded by qgroup
3612	 */
3613	path->search_commit_root = 1;
3614	path->skip_locking = 1;
3615
3616	err = 0;
3617	while (!err && !(stopped = rescan_should_stop(fs_info))) {
3618		trans = btrfs_start_transaction(fs_info->fs_root, 0);
3619		if (IS_ERR(trans)) {
3620			err = PTR_ERR(trans);
3621			break;
3622		}
3623
3624		err = qgroup_rescan_leaf(trans, path);
3625		did_leaf_rescans = true;
3626
 
3627		if (err > 0)
3628			btrfs_commit_transaction(trans);
3629		else
3630			btrfs_end_transaction(trans);
3631	}
3632
3633out:
3634	btrfs_free_path(path);
3635
3636	mutex_lock(&fs_info->qgroup_rescan_lock);
3637	if (err > 0 &&
3638	    fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3639		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3640	} else if (err < 0 || stopped) {
3641		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3642	}
3643	mutex_unlock(&fs_info->qgroup_rescan_lock);
3644
3645	/*
3646	 * Only update status, since the previous part has already updated the
3647	 * qgroup info, and only if we did any actual work. This also prevents
3648	 * race with a concurrent quota disable, which has already set
3649	 * fs_info->quota_root to NULL and cleared BTRFS_FS_QUOTA_ENABLED at
3650	 * btrfs_quota_disable().
3651	 */
3652	if (did_leaf_rescans) {
3653		trans = btrfs_start_transaction(fs_info->quota_root, 1);
3654		if (IS_ERR(trans)) {
3655			err = PTR_ERR(trans);
3656			trans = NULL;
3657			btrfs_err(fs_info,
3658				  "fail to start transaction for status update: %d",
3659				  err);
3660		}
3661	} else {
3662		trans = NULL;
 
 
 
3663	}
3664
3665	mutex_lock(&fs_info->qgroup_rescan_lock);
3666	if (!stopped ||
3667	    fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3668		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3669	if (trans) {
3670		ret = update_qgroup_status_item(trans);
3671		if (ret < 0) {
3672			err = ret;
3673			btrfs_err(fs_info, "fail to update qgroup status: %d",
3674				  err);
3675		}
3676	}
3677	fs_info->qgroup_rescan_running = false;
3678	fs_info->qgroup_flags &= ~BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN;
3679	complete_all(&fs_info->qgroup_rescan_completion);
3680	mutex_unlock(&fs_info->qgroup_rescan_lock);
3681
3682	if (!trans)
3683		return;
3684
3685	btrfs_end_transaction(trans);
3686
3687	if (stopped) {
3688		btrfs_info(fs_info, "qgroup scan paused");
3689	} else if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) {
3690		btrfs_info(fs_info, "qgroup scan cancelled");
3691	} else if (err >= 0) {
3692		btrfs_info(fs_info, "qgroup scan completed%s",
3693			err > 0 ? " (inconsistency flag cleared)" : "");
3694	} else {
3695		btrfs_err(fs_info, "qgroup scan failed with %d", err);
3696	}
3697}
3698
3699/*
3700 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3701 * memory required for the rescan context.
3702 */
3703static int
3704qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3705		   int init_flags)
3706{
3707	int ret = 0;
3708
3709	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) {
3710		btrfs_warn(fs_info, "qgroup rescan init failed, running in simple mode");
3711		return -EINVAL;
3712	}
3713
3714	if (!init_flags) {
3715		/* we're resuming qgroup rescan at mount time */
3716		if (!(fs_info->qgroup_flags &
3717		      BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3718			btrfs_warn(fs_info,
3719			"qgroup rescan init failed, qgroup rescan is not queued");
3720			ret = -EINVAL;
3721		} else if (!(fs_info->qgroup_flags &
3722			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3723			btrfs_warn(fs_info,
3724			"qgroup rescan init failed, qgroup is not enabled");
3725			ret = -EINVAL;
3726		}
3727
3728		if (ret)
3729			return ret;
3730	}
3731
3732	mutex_lock(&fs_info->qgroup_rescan_lock);
 
3733
3734	if (init_flags) {
3735		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3736			btrfs_warn(fs_info,
3737				   "qgroup rescan is already in progress");
3738			ret = -EINPROGRESS;
3739		} else if (!(fs_info->qgroup_flags &
3740			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3741			btrfs_warn(fs_info,
3742			"qgroup rescan init failed, qgroup is not enabled");
3743			ret = -EINVAL;
3744		} else if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
3745			/* Quota disable is in progress */
3746			ret = -EBUSY;
3747		}
3748
3749		if (ret) {
 
3750			mutex_unlock(&fs_info->qgroup_rescan_lock);
3751			return ret;
3752		}
3753		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3754	}
3755
3756	memset(&fs_info->qgroup_rescan_progress, 0,
3757		sizeof(fs_info->qgroup_rescan_progress));
3758	fs_info->qgroup_flags &= ~(BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
3759				   BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
3760	fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3761	init_completion(&fs_info->qgroup_rescan_completion);
 
 
 
3762	mutex_unlock(&fs_info->qgroup_rescan_lock);
3763
 
 
3764	btrfs_init_work(&fs_info->qgroup_rescan_work,
3765			btrfs_qgroup_rescan_worker, NULL);
 
3766	return 0;
3767}
3768
3769static void
3770qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3771{
3772	struct rb_node *n;
3773	struct btrfs_qgroup *qgroup;
3774
3775	spin_lock(&fs_info->qgroup_lock);
3776	/* clear all current qgroup tracking information */
3777	for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3778		qgroup = rb_entry(n, struct btrfs_qgroup, node);
3779		qgroup->rfer = 0;
3780		qgroup->rfer_cmpr = 0;
3781		qgroup->excl = 0;
3782		qgroup->excl_cmpr = 0;
3783		qgroup_dirty(fs_info, qgroup);
3784	}
3785	spin_unlock(&fs_info->qgroup_lock);
3786}
3787
3788int
3789btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3790{
3791	int ret = 0;
3792	struct btrfs_trans_handle *trans;
3793
3794	ret = qgroup_rescan_init(fs_info, 0, 1);
3795	if (ret)
3796		return ret;
3797
3798	/*
3799	 * We have set the rescan_progress to 0, which means no more
3800	 * delayed refs will be accounted by btrfs_qgroup_account_ref.
3801	 * However, btrfs_qgroup_account_ref may be right after its call
3802	 * to btrfs_find_all_roots, in which case it would still do the
3803	 * accounting.
3804	 * To solve this, we're committing the transaction, which will
3805	 * ensure we run all delayed refs and only after that, we are
3806	 * going to clear all tracking information for a clean start.
3807	 */
3808
3809	trans = btrfs_attach_transaction_barrier(fs_info->fs_root);
3810	if (IS_ERR(trans) && trans != ERR_PTR(-ENOENT)) {
3811		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3812		return PTR_ERR(trans);
3813	} else if (trans != ERR_PTR(-ENOENT)) {
3814		ret = btrfs_commit_transaction(trans);
3815		if (ret) {
3816			fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3817			return ret;
3818		}
3819	}
3820
3821	qgroup_rescan_zero_tracking(fs_info);
3822
3823	mutex_lock(&fs_info->qgroup_rescan_lock);
3824	fs_info->qgroup_rescan_running = true;
3825	btrfs_queue_work(fs_info->qgroup_rescan_workers,
3826			 &fs_info->qgroup_rescan_work);
3827	mutex_unlock(&fs_info->qgroup_rescan_lock);
3828
3829	return 0;
3830}
3831
3832int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3833				     bool interruptible)
3834{
3835	int running;
3836	int ret = 0;
3837
3838	mutex_lock(&fs_info->qgroup_rescan_lock);
 
3839	running = fs_info->qgroup_rescan_running;
 
3840	mutex_unlock(&fs_info->qgroup_rescan_lock);
3841
3842	if (!running)
3843		return 0;
3844
3845	if (interruptible)
3846		ret = wait_for_completion_interruptible(
3847					&fs_info->qgroup_rescan_completion);
3848	else
3849		wait_for_completion(&fs_info->qgroup_rescan_completion);
3850
3851	return ret;
3852}
3853
3854/*
3855 * this is only called from open_ctree where we're still single threaded, thus
3856 * locking is omitted here.
3857 */
3858void
3859btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3860{
3861	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3862		mutex_lock(&fs_info->qgroup_rescan_lock);
3863		fs_info->qgroup_rescan_running = true;
3864		btrfs_queue_work(fs_info->qgroup_rescan_workers,
3865				 &fs_info->qgroup_rescan_work);
3866		mutex_unlock(&fs_info->qgroup_rescan_lock);
3867	}
3868}
3869
3870#define rbtree_iterate_from_safe(node, next, start)				\
3871       for (node = start; node && ({ next = rb_next(node); 1;}); node = next)
3872
3873static int qgroup_unreserve_range(struct btrfs_inode *inode,
3874				  struct extent_changeset *reserved, u64 start,
3875				  u64 len)
3876{
3877	struct rb_node *node;
3878	struct rb_node *next;
3879	struct ulist_node *entry;
3880	int ret = 0;
3881
3882	node = reserved->range_changed.root.rb_node;
3883	if (!node)
3884		return 0;
3885	while (node) {
3886		entry = rb_entry(node, struct ulist_node, rb_node);
3887		if (entry->val < start)
3888			node = node->rb_right;
3889		else
3890			node = node->rb_left;
3891	}
3892
3893	if (entry->val > start && rb_prev(&entry->rb_node))
3894		entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node,
3895				 rb_node);
3896
3897	rbtree_iterate_from_safe(node, next, &entry->rb_node) {
3898		u64 entry_start;
3899		u64 entry_end;
3900		u64 entry_len;
3901		int clear_ret;
3902
3903		entry = rb_entry(node, struct ulist_node, rb_node);
3904		entry_start = entry->val;
3905		entry_end = entry->aux;
3906		entry_len = entry_end - entry_start + 1;
3907
3908		if (entry_start >= start + len)
3909			break;
3910		if (entry_start + entry_len <= start)
3911			continue;
3912		/*
3913		 * Now the entry is in [start, start + len), revert the
3914		 * EXTENT_QGROUP_RESERVED bit.
3915		 */
3916		clear_ret = clear_extent_bits(&inode->io_tree, entry_start,
3917					      entry_end, EXTENT_QGROUP_RESERVED);
3918		if (!ret && clear_ret < 0)
3919			ret = clear_ret;
3920
3921		ulist_del(&reserved->range_changed, entry->val, entry->aux);
3922		if (likely(reserved->bytes_changed >= entry_len)) {
3923			reserved->bytes_changed -= entry_len;
3924		} else {
3925			WARN_ON(1);
3926			reserved->bytes_changed = 0;
3927		}
3928	}
3929
3930	return ret;
3931}
3932
3933/*
3934 * Try to free some space for qgroup.
 
 
 
3935 *
3936 * For qgroup, there are only 3 ways to free qgroup space:
3937 * - Flush nodatacow write
3938 *   Any nodatacow write will free its reserved data space at run_delalloc_range().
3939 *   In theory, we should only flush nodatacow inodes, but it's not yet
3940 *   possible, so we need to flush the whole root.
3941 *
3942 * - Wait for ordered extents
3943 *   When ordered extents are finished, their reserved metadata is finally
3944 *   converted to per_trans status, which can be freed by later commit
3945 *   transaction.
3946 *
3947 * - Commit transaction
3948 *   This would free the meta_per_trans space.
3949 *   In theory this shouldn't provide much space, but any more qgroup space
3950 *   is needed.
3951 */
3952static int try_flush_qgroup(struct btrfs_root *root)
3953{
3954	struct btrfs_trans_handle *trans;
3955	int ret;
3956
3957	/* Can't hold an open transaction or we run the risk of deadlocking. */
3958	ASSERT(current->journal_info == NULL);
3959	if (WARN_ON(current->journal_info))
3960		return 0;
3961
3962	/*
3963	 * We don't want to run flush again and again, so if there is a running
3964	 * one, we won't try to start a new flush, but exit directly.
3965	 */
3966	if (test_and_set_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)) {
3967		wait_event(root->qgroup_flush_wait,
3968			!test_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state));
3969		return 0;
3970	}
3971
3972	ret = btrfs_start_delalloc_snapshot(root, true);
3973	if (ret < 0)
3974		goto out;
3975	btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
3976
3977	trans = btrfs_attach_transaction_barrier(root);
3978	if (IS_ERR(trans)) {
3979		ret = PTR_ERR(trans);
3980		if (ret == -ENOENT)
3981			ret = 0;
3982		goto out;
3983	}
3984
3985	ret = btrfs_commit_transaction(trans);
3986out:
3987	clear_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state);
3988	wake_up(&root->qgroup_flush_wait);
3989	return ret;
3990}
3991
3992static int qgroup_reserve_data(struct btrfs_inode *inode,
3993			struct extent_changeset **reserved_ret, u64 start,
3994			u64 len)
3995{
3996	struct btrfs_root *root = inode->root;
 
 
3997	struct extent_changeset *reserved;
3998	bool new_reserved = false;
3999	u64 orig_reserved;
4000	u64 to_reserve;
4001	int ret;
4002
4003	if (btrfs_qgroup_mode(root->fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4004	    !is_fstree(root->root_key.objectid) || len == 0)
4005		return 0;
4006
4007	/* @reserved parameter is mandatory for qgroup */
4008	if (WARN_ON(!reserved_ret))
4009		return -EINVAL;
4010	if (!*reserved_ret) {
4011		new_reserved = true;
4012		*reserved_ret = extent_changeset_alloc();
4013		if (!*reserved_ret)
4014			return -ENOMEM;
4015	}
4016	reserved = *reserved_ret;
4017	/* Record already reserved space */
4018	orig_reserved = reserved->bytes_changed;
4019	ret = set_record_extent_bits(&inode->io_tree, start,
4020			start + len -1, EXTENT_QGROUP_RESERVED, reserved);
4021
4022	/* Newly reserved space */
4023	to_reserve = reserved->bytes_changed - orig_reserved;
4024	trace_btrfs_qgroup_reserve_data(&inode->vfs_inode, start, len,
4025					to_reserve, QGROUP_RESERVE);
4026	if (ret < 0)
4027		goto out;
4028	ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
4029	if (ret < 0)
4030		goto cleanup;
4031
4032	return ret;
4033
4034cleanup:
4035	qgroup_unreserve_range(inode, reserved, start, len);
4036out:
4037	if (new_reserved) {
4038		extent_changeset_free(reserved);
4039		*reserved_ret = NULL;
4040	}
 
 
 
4041	return ret;
4042}
4043
4044/*
4045 * Reserve qgroup space for range [start, start + len).
4046 *
4047 * This function will either reserve space from related qgroups or do nothing
4048 * if the range is already reserved.
4049 *
4050 * Return 0 for successful reservation
4051 * Return <0 for error (including -EQUOT)
4052 *
4053 * NOTE: This function may sleep for memory allocation, dirty page flushing and
4054 *	 commit transaction. So caller should not hold any dirty page locked.
4055 */
4056int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
4057			struct extent_changeset **reserved_ret, u64 start,
4058			u64 len)
4059{
4060	int ret;
4061
4062	ret = qgroup_reserve_data(inode, reserved_ret, start, len);
4063	if (ret <= 0 && ret != -EDQUOT)
4064		return ret;
4065
4066	ret = try_flush_qgroup(inode->root);
4067	if (ret < 0)
4068		return ret;
4069	return qgroup_reserve_data(inode, reserved_ret, start, len);
4070}
4071
4072/* Free ranges specified by @reserved, normally in error path */
4073static int qgroup_free_reserved_data(struct btrfs_inode *inode,
4074				     struct extent_changeset *reserved,
4075				     u64 start, u64 len, u64 *freed_ret)
4076{
4077	struct btrfs_root *root = inode->root;
4078	struct ulist_node *unode;
4079	struct ulist_iterator uiter;
4080	struct extent_changeset changeset;
4081	u64 freed = 0;
4082	int ret;
4083
4084	extent_changeset_init(&changeset);
4085	len = round_up(start + len, root->fs_info->sectorsize);
4086	start = round_down(start, root->fs_info->sectorsize);
4087
4088	ULIST_ITER_INIT(&uiter);
4089	while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
4090		u64 range_start = unode->val;
4091		/* unode->aux is the inclusive end */
4092		u64 range_len = unode->aux - range_start + 1;
4093		u64 free_start;
4094		u64 free_len;
4095
4096		extent_changeset_release(&changeset);
4097
4098		/* Only free range in range [start, start + len) */
4099		if (range_start >= start + len ||
4100		    range_start + range_len <= start)
4101			continue;
4102		free_start = max(range_start, start);
4103		free_len = min(start + len, range_start + range_len) -
4104			   free_start;
4105		/*
4106		 * TODO: To also modify reserved->ranges_reserved to reflect
4107		 * the modification.
4108		 *
4109		 * However as long as we free qgroup reserved according to
4110		 * EXTENT_QGROUP_RESERVED, we won't double free.
4111		 * So not need to rush.
4112		 */
4113		ret = clear_record_extent_bits(&inode->io_tree, free_start,
4114				free_start + free_len - 1,
4115				EXTENT_QGROUP_RESERVED, &changeset);
4116		if (ret < 0)
4117			goto out;
4118		freed += changeset.bytes_changed;
4119	}
4120	btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
4121				  BTRFS_QGROUP_RSV_DATA);
4122	if (freed_ret)
4123		*freed_ret = freed;
4124	ret = 0;
4125out:
4126	extent_changeset_release(&changeset);
4127	return ret;
4128}
4129
4130static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
4131			struct extent_changeset *reserved, u64 start, u64 len,
4132			u64 *released, int free)
4133{
4134	struct extent_changeset changeset;
4135	int trace_op = QGROUP_RELEASE;
4136	int ret;
4137
4138	if (btrfs_qgroup_mode(inode->root->fs_info) == BTRFS_QGROUP_MODE_DISABLED) {
4139		extent_changeset_init(&changeset);
4140		return clear_record_extent_bits(&inode->io_tree, start,
4141						start + len - 1,
4142						EXTENT_QGROUP_RESERVED, &changeset);
4143	}
4144
4145	/* In release case, we shouldn't have @reserved */
4146	WARN_ON(!free && reserved);
4147	if (free && reserved)
4148		return qgroup_free_reserved_data(inode, reserved, start, len, released);
4149	extent_changeset_init(&changeset);
4150	ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1,
4151				       EXTENT_QGROUP_RESERVED, &changeset);
4152	if (ret < 0)
4153		goto out;
4154
4155	if (free)
4156		trace_op = QGROUP_FREE;
4157	trace_btrfs_qgroup_release_data(&inode->vfs_inode, start, len,
4158					changeset.bytes_changed, trace_op);
4159	if (free)
4160		btrfs_qgroup_free_refroot(inode->root->fs_info,
4161				inode->root->root_key.objectid,
4162				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4163	if (released)
4164		*released = changeset.bytes_changed;
4165out:
4166	extent_changeset_release(&changeset);
4167	return ret;
4168}
4169
4170/*
4171 * Free a reserved space range from io_tree and related qgroups
4172 *
4173 * Should be called when a range of pages get invalidated before reaching disk.
4174 * Or for error cleanup case.
4175 * if @reserved is given, only reserved range in [@start, @start + @len) will
4176 * be freed.
4177 *
4178 * For data written to disk, use btrfs_qgroup_release_data().
4179 *
4180 * NOTE: This function may sleep for memory allocation.
4181 */
4182int btrfs_qgroup_free_data(struct btrfs_inode *inode,
4183			   struct extent_changeset *reserved,
4184			   u64 start, u64 len, u64 *freed)
4185{
4186	return __btrfs_qgroup_release_data(inode, reserved, start, len, freed, 1);
4187}
4188
4189/*
4190 * Release a reserved space range from io_tree only.
4191 *
4192 * Should be called when a range of pages get written to disk and corresponding
4193 * FILE_EXTENT is inserted into corresponding root.
4194 *
4195 * Since new qgroup accounting framework will only update qgroup numbers at
4196 * commit_transaction() time, its reserved space shouldn't be freed from
4197 * related qgroups.
4198 *
4199 * But we should release the range from io_tree, to allow further write to be
4200 * COWed.
4201 *
4202 * NOTE: This function may sleep for memory allocation.
4203 */
4204int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released)
4205{
4206	return __btrfs_qgroup_release_data(inode, NULL, start, len, released, 0);
4207}
4208
4209static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4210			      enum btrfs_qgroup_rsv_type type)
4211{
4212	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4213	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
4214		return;
4215	if (num_bytes == 0)
4216		return;
4217
4218	spin_lock(&root->qgroup_meta_rsv_lock);
4219	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
4220		root->qgroup_meta_rsv_prealloc += num_bytes;
4221	else
4222		root->qgroup_meta_rsv_pertrans += num_bytes;
4223	spin_unlock(&root->qgroup_meta_rsv_lock);
4224}
4225
4226static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
4227			     enum btrfs_qgroup_rsv_type type)
4228{
4229	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
4230	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
4231		return 0;
4232	if (num_bytes == 0)
4233		return 0;
4234
4235	spin_lock(&root->qgroup_meta_rsv_lock);
4236	if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
4237		num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
4238				  num_bytes);
4239		root->qgroup_meta_rsv_prealloc -= num_bytes;
4240	} else {
4241		num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
4242				  num_bytes);
4243		root->qgroup_meta_rsv_pertrans -= num_bytes;
4244	}
4245	spin_unlock(&root->qgroup_meta_rsv_lock);
4246	return num_bytes;
4247}
4248
4249int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4250			      enum btrfs_qgroup_rsv_type type, bool enforce)
4251{
4252	struct btrfs_fs_info *fs_info = root->fs_info;
4253	int ret;
4254
4255	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4256	    !is_fstree(root->root_key.objectid) || num_bytes == 0)
4257		return 0;
4258
4259	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4260	trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
4261	ret = qgroup_reserve(root, num_bytes, enforce, type);
4262	if (ret < 0)
4263		return ret;
4264	/*
4265	 * Record what we have reserved into root.
4266	 *
4267	 * To avoid quota disabled->enabled underflow.
4268	 * In that case, we may try to free space we haven't reserved
4269	 * (since quota was disabled), so record what we reserved into root.
4270	 * And ensure later release won't underflow this number.
4271	 */
4272	add_root_meta_rsv(root, num_bytes, type);
4273	return ret;
4274}
4275
4276int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4277				enum btrfs_qgroup_rsv_type type, bool enforce,
4278				bool noflush)
4279{
4280	int ret;
4281
4282	ret = btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4283	if ((ret <= 0 && ret != -EDQUOT) || noflush)
4284		return ret;
4285
4286	ret = try_flush_qgroup(root);
4287	if (ret < 0)
4288		return ret;
4289	return btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4290}
4291
4292/*
4293 * Per-transaction meta reservation should be all freed at transaction commit
4294 * time
4295 */
4296void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
4297{
4298	struct btrfs_fs_info *fs_info = root->fs_info;
4299
4300	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4301	    !is_fstree(root->root_key.objectid))
4302		return;
4303
4304	/* TODO: Update trace point to handle such free */
4305	trace_qgroup_meta_free_all_pertrans(root);
4306	/* Special value -1 means to free all reserved space */
4307	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
4308				  BTRFS_QGROUP_RSV_META_PERTRANS);
4309}
4310
4311void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
4312			      enum btrfs_qgroup_rsv_type type)
4313{
4314	struct btrfs_fs_info *fs_info = root->fs_info;
4315
4316	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4317	    !is_fstree(root->root_key.objectid))
4318		return;
4319
4320	/*
4321	 * reservation for META_PREALLOC can happen before quota is enabled,
4322	 * which can lead to underflow.
4323	 * Here ensure we will only free what we really have reserved.
4324	 */
4325	num_bytes = sub_root_meta_rsv(root, num_bytes, type);
4326	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4327	trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
4328	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
4329				  num_bytes, type);
4330}
4331
4332static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
4333				int num_bytes)
4334{
 
4335	struct btrfs_qgroup *qgroup;
4336	LIST_HEAD(qgroup_list);
 
 
4337
4338	if (num_bytes == 0)
4339		return;
4340	if (!fs_info->quota_root)
4341		return;
4342
4343	spin_lock(&fs_info->qgroup_lock);
4344	qgroup = find_qgroup_rb(fs_info, ref_root);
4345	if (!qgroup)
4346		goto out;
 
 
 
 
 
 
 
 
 
4347
4348	qgroup_iterator_add(&qgroup_list, qgroup);
4349	list_for_each_entry(qgroup, &qgroup_list, iterator) {
4350		struct btrfs_qgroup_list *glist;
4351
4352		qgroup_rsv_release(fs_info, qgroup, num_bytes,
4353				BTRFS_QGROUP_RSV_META_PREALLOC);
4354		if (!sb_rdonly(fs_info->sb))
4355			qgroup_rsv_add(fs_info, qgroup, num_bytes,
4356				       BTRFS_QGROUP_RSV_META_PERTRANS);
4357
4358		list_for_each_entry(glist, &qgroup->groups, next_group)
4359			qgroup_iterator_add(&qgroup_list, glist->group);
 
 
 
4360	}
4361out:
4362	qgroup_iterator_clean(&qgroup_list);
4363	spin_unlock(&fs_info->qgroup_lock);
4364}
4365
4366/*
4367 * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS.
4368 *
4369 * This is called when preallocated meta reservation needs to be used.
4370 * Normally after btrfs_join_transaction() call.
4371 */
4372void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
4373{
4374	struct btrfs_fs_info *fs_info = root->fs_info;
4375
4376	if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED ||
4377	    !is_fstree(root->root_key.objectid))
4378		return;
4379	/* Same as btrfs_qgroup_free_meta_prealloc() */
4380	num_bytes = sub_root_meta_rsv(root, num_bytes,
4381				      BTRFS_QGROUP_RSV_META_PREALLOC);
4382	trace_qgroup_meta_convert(root, num_bytes);
4383	qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
4384}
4385
4386/*
4387 * Check qgroup reserved space leaking, normally at destroy inode
4388 * time
4389 */
4390void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode)
4391{
4392	struct extent_changeset changeset;
4393	struct ulist_node *unode;
4394	struct ulist_iterator iter;
4395	int ret;
4396
4397	extent_changeset_init(&changeset);
4398	ret = clear_record_extent_bits(&inode->io_tree, 0, (u64)-1,
4399			EXTENT_QGROUP_RESERVED, &changeset);
4400
4401	WARN_ON(ret < 0);
4402	if (WARN_ON(changeset.bytes_changed)) {
4403		ULIST_ITER_INIT(&iter);
4404		while ((unode = ulist_next(&changeset.range_changed, &iter))) {
4405			btrfs_warn(inode->root->fs_info,
4406		"leaking qgroup reserved space, ino: %llu, start: %llu, end: %llu",
4407				btrfs_ino(inode), unode->val, unode->aux);
4408		}
4409		btrfs_qgroup_free_refroot(inode->root->fs_info,
4410				inode->root->root_key.objectid,
4411				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4412
4413	}
4414	extent_changeset_release(&changeset);
4415}
4416
4417void btrfs_qgroup_init_swapped_blocks(
4418	struct btrfs_qgroup_swapped_blocks *swapped_blocks)
4419{
4420	int i;
4421
4422	spin_lock_init(&swapped_blocks->lock);
4423	for (i = 0; i < BTRFS_MAX_LEVEL; i++)
4424		swapped_blocks->blocks[i] = RB_ROOT;
4425	swapped_blocks->swapped = false;
4426}
4427
4428/*
4429 * Delete all swapped blocks record of @root.
4430 * Every record here means we skipped a full subtree scan for qgroup.
4431 *
4432 * Gets called when committing one transaction.
4433 */
4434void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root)
4435{
4436	struct btrfs_qgroup_swapped_blocks *swapped_blocks;
4437	int i;
4438
4439	swapped_blocks = &root->swapped_blocks;
4440
4441	spin_lock(&swapped_blocks->lock);
4442	if (!swapped_blocks->swapped)
4443		goto out;
4444	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4445		struct rb_root *cur_root = &swapped_blocks->blocks[i];
4446		struct btrfs_qgroup_swapped_block *entry;
4447		struct btrfs_qgroup_swapped_block *next;
4448
4449		rbtree_postorder_for_each_entry_safe(entry, next, cur_root,
4450						     node)
4451			kfree(entry);
4452		swapped_blocks->blocks[i] = RB_ROOT;
4453	}
4454	swapped_blocks->swapped = false;
4455out:
4456	spin_unlock(&swapped_blocks->lock);
4457}
4458
4459/*
4460 * Add subtree roots record into @subvol_root.
4461 *
4462 * @subvol_root:	tree root of the subvolume tree get swapped
4463 * @bg:			block group under balance
4464 * @subvol_parent/slot:	pointer to the subtree root in subvolume tree
4465 * @reloc_parent/slot:	pointer to the subtree root in reloc tree
4466 *			BOTH POINTERS ARE BEFORE TREE SWAP
4467 * @last_snapshot:	last snapshot generation of the subvolume tree
4468 */
4469int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
4470		struct btrfs_root *subvol_root,
4471		struct btrfs_block_group *bg,
4472		struct extent_buffer *subvol_parent, int subvol_slot,
4473		struct extent_buffer *reloc_parent, int reloc_slot,
4474		u64 last_snapshot)
4475{
4476	struct btrfs_fs_info *fs_info = subvol_root->fs_info;
4477	struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks;
4478	struct btrfs_qgroup_swapped_block *block;
4479	struct rb_node **cur;
4480	struct rb_node *parent = NULL;
4481	int level = btrfs_header_level(subvol_parent) - 1;
4482	int ret = 0;
4483
4484	if (!btrfs_qgroup_full_accounting(fs_info))
4485		return 0;
4486
4487	if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) >
4488	    btrfs_node_ptr_generation(reloc_parent, reloc_slot)) {
4489		btrfs_err_rl(fs_info,
4490		"%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu",
4491			__func__,
4492			btrfs_node_ptr_generation(subvol_parent, subvol_slot),
4493			btrfs_node_ptr_generation(reloc_parent, reloc_slot));
4494		return -EUCLEAN;
4495	}
4496
4497	block = kmalloc(sizeof(*block), GFP_NOFS);
4498	if (!block) {
4499		ret = -ENOMEM;
4500		goto out;
4501	}
4502
4503	/*
4504	 * @reloc_parent/slot is still before swap, while @block is going to
4505	 * record the bytenr after swap, so we do the swap here.
4506	 */
4507	block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot);
4508	block->subvol_generation = btrfs_node_ptr_generation(reloc_parent,
4509							     reloc_slot);
4510	block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot);
4511	block->reloc_generation = btrfs_node_ptr_generation(subvol_parent,
4512							    subvol_slot);
4513	block->last_snapshot = last_snapshot;
4514	block->level = level;
4515
4516	/*
4517	 * If we have bg == NULL, we're called from btrfs_recover_relocation(),
4518	 * no one else can modify tree blocks thus we qgroup will not change
4519	 * no matter the value of trace_leaf.
4520	 */
4521	if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA)
4522		block->trace_leaf = true;
4523	else
4524		block->trace_leaf = false;
4525	btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot);
4526
4527	/* Insert @block into @blocks */
4528	spin_lock(&blocks->lock);
4529	cur = &blocks->blocks[level].rb_node;
4530	while (*cur) {
4531		struct btrfs_qgroup_swapped_block *entry;
4532
4533		parent = *cur;
4534		entry = rb_entry(parent, struct btrfs_qgroup_swapped_block,
4535				 node);
4536
4537		if (entry->subvol_bytenr < block->subvol_bytenr) {
4538			cur = &(*cur)->rb_left;
4539		} else if (entry->subvol_bytenr > block->subvol_bytenr) {
4540			cur = &(*cur)->rb_right;
4541		} else {
4542			if (entry->subvol_generation !=
4543					block->subvol_generation ||
4544			    entry->reloc_bytenr != block->reloc_bytenr ||
4545			    entry->reloc_generation !=
4546					block->reloc_generation) {
4547				/*
4548				 * Duplicated but mismatch entry found.
4549				 * Shouldn't happen.
4550				 *
4551				 * Marking qgroup inconsistent should be enough
4552				 * for end users.
4553				 */
4554				WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4555				ret = -EEXIST;
4556			}
4557			kfree(block);
4558			goto out_unlock;
4559		}
4560	}
4561	rb_link_node(&block->node, parent, cur);
4562	rb_insert_color(&block->node, &blocks->blocks[level]);
4563	blocks->swapped = true;
4564out_unlock:
4565	spin_unlock(&blocks->lock);
4566out:
4567	if (ret < 0)
4568		qgroup_mark_inconsistent(fs_info);
 
4569	return ret;
4570}
4571
4572/*
4573 * Check if the tree block is a subtree root, and if so do the needed
4574 * delayed subtree trace for qgroup.
4575 *
4576 * This is called during btrfs_cow_block().
4577 */
4578int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
4579					 struct btrfs_root *root,
4580					 struct extent_buffer *subvol_eb)
4581{
4582	struct btrfs_fs_info *fs_info = root->fs_info;
4583	struct btrfs_tree_parent_check check = { 0 };
4584	struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks;
4585	struct btrfs_qgroup_swapped_block *block;
4586	struct extent_buffer *reloc_eb = NULL;
4587	struct rb_node *node;
4588	bool found = false;
4589	bool swapped = false;
4590	int level = btrfs_header_level(subvol_eb);
4591	int ret = 0;
4592	int i;
4593
4594	if (!btrfs_qgroup_full_accounting(fs_info))
4595		return 0;
4596	if (!is_fstree(root->root_key.objectid) || !root->reloc_root)
4597		return 0;
4598
4599	spin_lock(&blocks->lock);
4600	if (!blocks->swapped) {
4601		spin_unlock(&blocks->lock);
4602		return 0;
4603	}
4604	node = blocks->blocks[level].rb_node;
4605
4606	while (node) {
4607		block = rb_entry(node, struct btrfs_qgroup_swapped_block, node);
4608		if (block->subvol_bytenr < subvol_eb->start) {
4609			node = node->rb_left;
4610		} else if (block->subvol_bytenr > subvol_eb->start) {
4611			node = node->rb_right;
4612		} else {
4613			found = true;
4614			break;
4615		}
4616	}
4617	if (!found) {
4618		spin_unlock(&blocks->lock);
4619		goto out;
4620	}
4621	/* Found one, remove it from @blocks first and update blocks->swapped */
4622	rb_erase(&block->node, &blocks->blocks[level]);
4623	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4624		if (RB_EMPTY_ROOT(&blocks->blocks[i])) {
4625			swapped = true;
4626			break;
4627		}
4628	}
4629	blocks->swapped = swapped;
4630	spin_unlock(&blocks->lock);
4631
4632	check.level = block->level;
4633	check.transid = block->reloc_generation;
4634	check.has_first_key = true;
4635	memcpy(&check.first_key, &block->first_key, sizeof(check.first_key));
4636
4637	/* Read out reloc subtree root */
4638	reloc_eb = read_tree_block(fs_info, block->reloc_bytenr, &check);
 
 
4639	if (IS_ERR(reloc_eb)) {
4640		ret = PTR_ERR(reloc_eb);
4641		reloc_eb = NULL;
4642		goto free_out;
4643	}
4644	if (!extent_buffer_uptodate(reloc_eb)) {
4645		ret = -EIO;
4646		goto free_out;
4647	}
4648
4649	ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb,
4650			block->last_snapshot, block->trace_leaf);
4651free_out:
4652	kfree(block);
4653	free_extent_buffer(reloc_eb);
4654out:
4655	if (ret < 0) {
4656		btrfs_err_rl(fs_info,
4657			     "failed to account subtree at bytenr %llu: %d",
4658			     subvol_eb->start, ret);
4659		qgroup_mark_inconsistent(fs_info);
4660	}
4661	return ret;
4662}
4663
4664void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans)
4665{
4666	struct btrfs_qgroup_extent_record *entry;
4667	struct btrfs_qgroup_extent_record *next;
4668	struct rb_root *root;
4669
4670	root = &trans->delayed_refs.dirty_extent_root;
4671	rbtree_postorder_for_each_entry_safe(entry, next, root, node) {
4672		ulist_free(entry->old_roots);
4673		kfree(entry);
4674	}
4675	*root = RB_ROOT;
4676}
4677
4678void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes)
4679{
4680	if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4681		return;
4682
4683	if (!is_fstree(root))
4684		return;
4685
4686	btrfs_qgroup_free_refroot(fs_info, root, rsv_bytes, BTRFS_QGROUP_RSV_DATA);
4687}
4688
4689int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info,
4690			      struct btrfs_squota_delta *delta)
4691{
4692	int ret;
4693	struct btrfs_qgroup *qgroup;
4694	struct btrfs_qgroup *qg;
4695	LIST_HEAD(qgroup_list);
4696	u64 root = delta->root;
4697	u64 num_bytes = delta->num_bytes;
4698	const int sign = (delta->is_inc ? 1 : -1);
4699
4700	if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE)
4701		return 0;
4702
4703	if (!is_fstree(root))
4704		return 0;
4705
4706	/* If the extent predates enabling quotas, don't count it. */
4707	if (delta->generation < fs_info->qgroup_enable_gen)
4708		return 0;
4709
4710	spin_lock(&fs_info->qgroup_lock);
4711	qgroup = find_qgroup_rb(fs_info, root);
4712	if (!qgroup) {
4713		ret = -ENOENT;
4714		goto out;
4715	}
4716
4717	ret = 0;
4718	qgroup_iterator_add(&qgroup_list, qgroup);
4719	list_for_each_entry(qg, &qgroup_list, iterator) {
4720		struct btrfs_qgroup_list *glist;
4721
4722		qg->excl += num_bytes * sign;
4723		qg->rfer += num_bytes * sign;
4724		qgroup_dirty(fs_info, qg);
4725
4726		list_for_each_entry(glist, &qg->groups, next_group)
4727			qgroup_iterator_add(&qgroup_list, glist->group);
4728	}
4729	qgroup_iterator_clean(&qgroup_list);
4730
4731out:
4732	spin_unlock(&fs_info->qgroup_lock);
4733	return ret;
4734}