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v6.2
   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
  33/*
  34 * Helpers to access qgroup reservation
  35 *
  36 * Callers should ensure the lock context and type are valid
  37 */
  38
  39static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup)
  40{
  41	u64 ret = 0;
  42	int i;
  43
  44	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
  45		ret += qgroup->rsv.values[i];
  46
  47	return ret;
  48}
  49
  50#ifdef CONFIG_BTRFS_DEBUG
  51static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type)
  52{
  53	if (type == BTRFS_QGROUP_RSV_DATA)
  54		return "data";
  55	if (type == BTRFS_QGROUP_RSV_META_PERTRANS)
  56		return "meta_pertrans";
  57	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
  58		return "meta_prealloc";
  59	return NULL;
  60}
  61#endif
  62
  63static void qgroup_rsv_add(struct btrfs_fs_info *fs_info,
  64			   struct btrfs_qgroup *qgroup, u64 num_bytes,
  65			   enum btrfs_qgroup_rsv_type type)
  66{
  67	trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type);
  68	qgroup->rsv.values[type] += num_bytes;
  69}
  70
  71static void qgroup_rsv_release(struct btrfs_fs_info *fs_info,
  72			       struct btrfs_qgroup *qgroup, u64 num_bytes,
  73			       enum btrfs_qgroup_rsv_type type)
  74{
  75	trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type);
  76	if (qgroup->rsv.values[type] >= num_bytes) {
  77		qgroup->rsv.values[type] -= num_bytes;
  78		return;
  79	}
  80#ifdef CONFIG_BTRFS_DEBUG
  81	WARN_RATELIMIT(1,
  82		"qgroup %llu %s reserved space underflow, have %llu to free %llu",
  83		qgroup->qgroupid, qgroup_rsv_type_str(type),
  84		qgroup->rsv.values[type], num_bytes);
  85#endif
  86	qgroup->rsv.values[type] = 0;
  87}
  88
  89static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info,
  90				     struct btrfs_qgroup *dest,
  91				     struct btrfs_qgroup *src)
  92{
  93	int i;
  94
  95	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
  96		qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i);
  97}
  98
  99static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info,
 100					 struct btrfs_qgroup *dest,
 101					  struct btrfs_qgroup *src)
 102{
 103	int i;
 104
 105	for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++)
 106		qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i);
 107}
 108
 109static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
 110					   int mod)
 111{
 112	if (qg->old_refcnt < seq)
 113		qg->old_refcnt = seq;
 114	qg->old_refcnt += mod;
 115}
 116
 117static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
 118					   int mod)
 119{
 120	if (qg->new_refcnt < seq)
 121		qg->new_refcnt = seq;
 122	qg->new_refcnt += mod;
 123}
 124
 125static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
 126{
 127	if (qg->old_refcnt < seq)
 128		return 0;
 129	return qg->old_refcnt - seq;
 130}
 131
 132static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
 133{
 134	if (qg->new_refcnt < seq)
 135		return 0;
 136	return qg->new_refcnt - seq;
 137}
 138
 139/*
 140 * glue structure to represent the relations between qgroups.
 141 */
 142struct btrfs_qgroup_list {
 143	struct list_head next_group;
 144	struct list_head next_member;
 145	struct btrfs_qgroup *group;
 146	struct btrfs_qgroup *member;
 147};
 148
 149static inline u64 qgroup_to_aux(struct btrfs_qgroup *qg)
 150{
 151	return (u64)(uintptr_t)qg;
 152}
 153
 154static inline struct btrfs_qgroup* unode_aux_to_qgroup(struct ulist_node *n)
 155{
 156	return (struct btrfs_qgroup *)(uintptr_t)n->aux;
 157}
 158
 159static int
 160qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
 161		   int init_flags);
 162static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 163
 164/* must be called with qgroup_ioctl_lock held */
 165static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
 166					   u64 qgroupid)
 167{
 168	struct rb_node *n = fs_info->qgroup_tree.rb_node;
 169	struct btrfs_qgroup *qgroup;
 170
 171	while (n) {
 172		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 173		if (qgroup->qgroupid < qgroupid)
 174			n = n->rb_left;
 175		else if (qgroup->qgroupid > qgroupid)
 176			n = n->rb_right;
 177		else
 178			return qgroup;
 179	}
 180	return NULL;
 181}
 182
 183/* must be called with qgroup_lock held */
 184static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
 185					  u64 qgroupid)
 186{
 187	struct rb_node **p = &fs_info->qgroup_tree.rb_node;
 188	struct rb_node *parent = NULL;
 189	struct btrfs_qgroup *qgroup;
 190
 191	while (*p) {
 192		parent = *p;
 193		qgroup = rb_entry(parent, struct btrfs_qgroup, node);
 194
 195		if (qgroup->qgroupid < qgroupid)
 196			p = &(*p)->rb_left;
 197		else if (qgroup->qgroupid > qgroupid)
 198			p = &(*p)->rb_right;
 199		else
 200			return qgroup;
 201	}
 202
 203	qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
 204	if (!qgroup)
 205		return ERR_PTR(-ENOMEM);
 206
 207	qgroup->qgroupid = qgroupid;
 208	INIT_LIST_HEAD(&qgroup->groups);
 209	INIT_LIST_HEAD(&qgroup->members);
 210	INIT_LIST_HEAD(&qgroup->dirty);
 211
 212	rb_link_node(&qgroup->node, parent, p);
 213	rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
 214
 215	return qgroup;
 216}
 217
 218static void __del_qgroup_rb(struct btrfs_fs_info *fs_info,
 219			    struct btrfs_qgroup *qgroup)
 220{
 221	struct btrfs_qgroup_list *list;
 222
 223	list_del(&qgroup->dirty);
 224	while (!list_empty(&qgroup->groups)) {
 225		list = list_first_entry(&qgroup->groups,
 226					struct btrfs_qgroup_list, next_group);
 227		list_del(&list->next_group);
 228		list_del(&list->next_member);
 229		kfree(list);
 230	}
 231
 232	while (!list_empty(&qgroup->members)) {
 233		list = list_first_entry(&qgroup->members,
 234					struct btrfs_qgroup_list, next_member);
 235		list_del(&list->next_group);
 236		list_del(&list->next_member);
 237		kfree(list);
 238	}
 
 239}
 240
 241/* must be called with qgroup_lock held */
 242static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
 243{
 244	struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
 245
 246	if (!qgroup)
 247		return -ENOENT;
 248
 249	rb_erase(&qgroup->node, &fs_info->qgroup_tree);
 250	__del_qgroup_rb(fs_info, qgroup);
 251	return 0;
 252}
 253
 254/*
 255 * Add relation specified by two qgroups.
 256 *
 257 * Must be called with qgroup_lock held.
 258 *
 259 * Return: 0        on success
 260 *         -ENOENT  if one of the qgroups is NULL
 261 *         <0       other errors
 262 */
 263static int __add_relation_rb(struct btrfs_qgroup *member, struct btrfs_qgroup *parent)
 264{
 
 
 265	struct btrfs_qgroup_list *list;
 266
 
 
 267	if (!member || !parent)
 268		return -ENOENT;
 269
 270	list = kzalloc(sizeof(*list), GFP_ATOMIC);
 271	if (!list)
 272		return -ENOMEM;
 273
 274	list->group = parent;
 275	list->member = member;
 276	list_add_tail(&list->next_group, &member->groups);
 277	list_add_tail(&list->next_member, &parent->members);
 278
 279	return 0;
 280}
 281
 282/*
 283 * Add relation specified by two qgroup ids.
 284 *
 285 * Must be called with qgroup_lock held.
 286 *
 287 * Return: 0        on success
 288 *         -ENOENT  if one of the ids does not exist
 289 *         <0       other errors
 290 */
 291static int add_relation_rb(struct btrfs_fs_info *fs_info, u64 memberid, u64 parentid)
 292{
 293	struct btrfs_qgroup *member;
 294	struct btrfs_qgroup *parent;
 295
 296	member = find_qgroup_rb(fs_info, memberid);
 297	parent = find_qgroup_rb(fs_info, parentid);
 298
 299	return __add_relation_rb(member, parent);
 300}
 301
 302/* Must be called with qgroup_lock held */
 303static int del_relation_rb(struct btrfs_fs_info *fs_info,
 304			   u64 memberid, u64 parentid)
 305{
 306	struct btrfs_qgroup *member;
 307	struct btrfs_qgroup *parent;
 308	struct btrfs_qgroup_list *list;
 309
 310	member = find_qgroup_rb(fs_info, memberid);
 311	parent = find_qgroup_rb(fs_info, parentid);
 312	if (!member || !parent)
 313		return -ENOENT;
 314
 315	list_for_each_entry(list, &member->groups, next_group) {
 316		if (list->group == parent) {
 317			list_del(&list->next_group);
 318			list_del(&list->next_member);
 319			kfree(list);
 320			return 0;
 321		}
 322	}
 323	return -ENOENT;
 324}
 325
 326#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 327int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
 328			       u64 rfer, u64 excl)
 329{
 330	struct btrfs_qgroup *qgroup;
 331
 332	qgroup = find_qgroup_rb(fs_info, qgroupid);
 333	if (!qgroup)
 334		return -EINVAL;
 335	if (qgroup->rfer != rfer || qgroup->excl != excl)
 336		return -EINVAL;
 337	return 0;
 338}
 339#endif
 340
 341static void qgroup_mark_inconsistent(struct btrfs_fs_info *fs_info)
 342{
 343	fs_info->qgroup_flags |= (BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT |
 344				  BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
 345				  BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
 346}
 347
 348/*
 349 * The full config is read in one go, only called from open_ctree()
 350 * It doesn't use any locking, as at this point we're still single-threaded
 351 */
 352int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
 353{
 354	struct btrfs_key key;
 355	struct btrfs_key found_key;
 356	struct btrfs_root *quota_root = fs_info->quota_root;
 357	struct btrfs_path *path = NULL;
 358	struct extent_buffer *l;
 359	int slot;
 360	int ret = 0;
 361	u64 flags = 0;
 362	u64 rescan_progress = 0;
 363
 364	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
 365		return 0;
 366
 367	fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 368	if (!fs_info->qgroup_ulist) {
 369		ret = -ENOMEM;
 370		goto out;
 371	}
 372
 373	path = btrfs_alloc_path();
 374	if (!path) {
 375		ret = -ENOMEM;
 376		goto out;
 377	}
 378
 379	ret = btrfs_sysfs_add_qgroups(fs_info);
 380	if (ret < 0)
 381		goto out;
 382	/* default this to quota off, in case no status key is found */
 383	fs_info->qgroup_flags = 0;
 384
 385	/*
 386	 * pass 1: read status, all qgroup infos and limits
 387	 */
 388	key.objectid = 0;
 389	key.type = 0;
 390	key.offset = 0;
 391	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
 392	if (ret)
 393		goto out;
 394
 395	while (1) {
 396		struct btrfs_qgroup *qgroup;
 397
 398		slot = path->slots[0];
 399		l = path->nodes[0];
 400		btrfs_item_key_to_cpu(l, &found_key, slot);
 401
 402		if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
 403			struct btrfs_qgroup_status_item *ptr;
 404
 405			ptr = btrfs_item_ptr(l, slot,
 406					     struct btrfs_qgroup_status_item);
 407
 408			if (btrfs_qgroup_status_version(l, ptr) !=
 409			    BTRFS_QGROUP_STATUS_VERSION) {
 410				btrfs_err(fs_info,
 411				 "old qgroup version, quota disabled");
 412				goto out;
 413			}
 414			if (btrfs_qgroup_status_generation(l, ptr) !=
 415			    fs_info->generation) {
 416				qgroup_mark_inconsistent(fs_info);
 417				btrfs_err(fs_info,
 418					"qgroup generation mismatch, marked as inconsistent");
 419			}
 420			fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
 421									  ptr);
 422			rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
 423			goto next1;
 424		}
 425
 426		if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
 427		    found_key.type != BTRFS_QGROUP_LIMIT_KEY)
 428			goto next1;
 429
 430		qgroup = find_qgroup_rb(fs_info, found_key.offset);
 431		if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
 432		    (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
 433			btrfs_err(fs_info, "inconsistent qgroup config");
 434			qgroup_mark_inconsistent(fs_info);
 435		}
 436		if (!qgroup) {
 437			qgroup = add_qgroup_rb(fs_info, found_key.offset);
 438			if (IS_ERR(qgroup)) {
 439				ret = PTR_ERR(qgroup);
 440				goto out;
 441			}
 442		}
 443		ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
 444		if (ret < 0)
 445			goto out;
 446
 447		switch (found_key.type) {
 448		case BTRFS_QGROUP_INFO_KEY: {
 449			struct btrfs_qgroup_info_item *ptr;
 450
 451			ptr = btrfs_item_ptr(l, slot,
 452					     struct btrfs_qgroup_info_item);
 453			qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
 454			qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
 455			qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
 456			qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
 457			/* generation currently unused */
 458			break;
 459		}
 460		case BTRFS_QGROUP_LIMIT_KEY: {
 461			struct btrfs_qgroup_limit_item *ptr;
 462
 463			ptr = btrfs_item_ptr(l, slot,
 464					     struct btrfs_qgroup_limit_item);
 465			qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
 466			qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
 467			qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
 468			qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
 469			qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
 470			break;
 471		}
 472		}
 473next1:
 474		ret = btrfs_next_item(quota_root, path);
 475		if (ret < 0)
 476			goto out;
 477		if (ret)
 478			break;
 479	}
 480	btrfs_release_path(path);
 481
 482	/*
 483	 * pass 2: read all qgroup relations
 484	 */
 485	key.objectid = 0;
 486	key.type = BTRFS_QGROUP_RELATION_KEY;
 487	key.offset = 0;
 488	ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
 489	if (ret)
 490		goto out;
 491	while (1) {
 492		slot = path->slots[0];
 493		l = path->nodes[0];
 494		btrfs_item_key_to_cpu(l, &found_key, slot);
 495
 496		if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
 497			goto next2;
 498
 499		if (found_key.objectid > found_key.offset) {
 500			/* parent <- member, not needed to build config */
 501			/* FIXME should we omit the key completely? */
 502			goto next2;
 503		}
 504
 505		ret = add_relation_rb(fs_info, found_key.objectid,
 506				      found_key.offset);
 507		if (ret == -ENOENT) {
 508			btrfs_warn(fs_info,
 509				"orphan qgroup relation 0x%llx->0x%llx",
 510				found_key.objectid, found_key.offset);
 511			ret = 0;	/* ignore the error */
 512		}
 513		if (ret)
 514			goto out;
 515next2:
 516		ret = btrfs_next_item(quota_root, path);
 517		if (ret < 0)
 518			goto out;
 519		if (ret)
 520			break;
 521	}
 522out:
 523	btrfs_free_path(path);
 524	fs_info->qgroup_flags |= flags;
 525	if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
 526		clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
 527	else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
 528		 ret >= 0)
 529		ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
 
 530
 531	if (ret < 0) {
 532		ulist_free(fs_info->qgroup_ulist);
 533		fs_info->qgroup_ulist = NULL;
 534		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
 535		btrfs_sysfs_del_qgroups(fs_info);
 536	}
 537
 538	return ret < 0 ? ret : 0;
 539}
 540
 541/*
 542 * Called in close_ctree() when quota is still enabled.  This verifies we don't
 543 * leak some reserved space.
 544 *
 545 * Return false if no reserved space is left.
 546 * Return true if some reserved space is leaked.
 547 */
 548bool btrfs_check_quota_leak(struct btrfs_fs_info *fs_info)
 549{
 550	struct rb_node *node;
 551	bool ret = false;
 552
 553	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
 554		return ret;
 555	/*
 556	 * Since we're unmounting, there is no race and no need to grab qgroup
 557	 * lock.  And here we don't go post-order to provide a more user
 558	 * friendly sorted result.
 559	 */
 560	for (node = rb_first(&fs_info->qgroup_tree); node; node = rb_next(node)) {
 561		struct btrfs_qgroup *qgroup;
 562		int i;
 563
 564		qgroup = rb_entry(node, struct btrfs_qgroup, node);
 565		for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) {
 566			if (qgroup->rsv.values[i]) {
 567				ret = true;
 568				btrfs_warn(fs_info,
 569		"qgroup %hu/%llu has unreleased space, type %d rsv %llu",
 570				   btrfs_qgroup_level(qgroup->qgroupid),
 571				   btrfs_qgroup_subvolid(qgroup->qgroupid),
 572				   i, qgroup->rsv.values[i]);
 573			}
 574		}
 575	}
 576	return ret;
 577}
 578
 579/*
 580 * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
 581 * first two are in single-threaded paths.And for the third one, we have set
 582 * quota_root to be null with qgroup_lock held before, so it is safe to clean
 583 * up the in-memory structures without qgroup_lock held.
 584 */
 585void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
 586{
 587	struct rb_node *n;
 588	struct btrfs_qgroup *qgroup;
 589
 590	while ((n = rb_first(&fs_info->qgroup_tree))) {
 591		qgroup = rb_entry(n, struct btrfs_qgroup, node);
 592		rb_erase(n, &fs_info->qgroup_tree);
 593		__del_qgroup_rb(fs_info, qgroup);
 594		btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
 595		kfree(qgroup);
 596	}
 597	/*
 598	 * We call btrfs_free_qgroup_config() when unmounting
 599	 * filesystem and disabling quota, so we set qgroup_ulist
 600	 * to be null here to avoid double free.
 601	 */
 602	ulist_free(fs_info->qgroup_ulist);
 603	fs_info->qgroup_ulist = NULL;
 604	btrfs_sysfs_del_qgroups(fs_info);
 605}
 606
 607static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 608				    u64 dst)
 
 609{
 610	int ret;
 611	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 612	struct btrfs_path *path;
 613	struct btrfs_key key;
 614
 615	path = btrfs_alloc_path();
 616	if (!path)
 617		return -ENOMEM;
 618
 619	key.objectid = src;
 620	key.type = BTRFS_QGROUP_RELATION_KEY;
 621	key.offset = dst;
 622
 623	ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
 624
 625	btrfs_mark_buffer_dirty(path->nodes[0]);
 626
 627	btrfs_free_path(path);
 628	return ret;
 629}
 630
 631static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src,
 632				    u64 dst)
 
 633{
 634	int ret;
 635	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 636	struct btrfs_path *path;
 637	struct btrfs_key key;
 638
 639	path = btrfs_alloc_path();
 640	if (!path)
 641		return -ENOMEM;
 642
 643	key.objectid = src;
 644	key.type = BTRFS_QGROUP_RELATION_KEY;
 645	key.offset = dst;
 646
 647	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 648	if (ret < 0)
 649		goto out;
 650
 651	if (ret > 0) {
 652		ret = -ENOENT;
 653		goto out;
 654	}
 655
 656	ret = btrfs_del_item(trans, quota_root, path);
 657out:
 658	btrfs_free_path(path);
 659	return ret;
 660}
 661
 662static int add_qgroup_item(struct btrfs_trans_handle *trans,
 663			   struct btrfs_root *quota_root, u64 qgroupid)
 664{
 665	int ret;
 666	struct btrfs_path *path;
 667	struct btrfs_qgroup_info_item *qgroup_info;
 668	struct btrfs_qgroup_limit_item *qgroup_limit;
 669	struct extent_buffer *leaf;
 670	struct btrfs_key key;
 671
 672	if (btrfs_is_testing(quota_root->fs_info))
 673		return 0;
 674
 675	path = btrfs_alloc_path();
 676	if (!path)
 677		return -ENOMEM;
 678
 679	key.objectid = 0;
 680	key.type = BTRFS_QGROUP_INFO_KEY;
 681	key.offset = qgroupid;
 682
 683	/*
 684	 * Avoid a transaction abort by catching -EEXIST here. In that
 685	 * case, we proceed by re-initializing the existing structure
 686	 * on disk.
 687	 */
 688
 689	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 690				      sizeof(*qgroup_info));
 691	if (ret && ret != -EEXIST)
 692		goto out;
 693
 694	leaf = path->nodes[0];
 695	qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
 696				 struct btrfs_qgroup_info_item);
 697	btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
 698	btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
 699	btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
 700	btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
 701	btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
 702
 703	btrfs_mark_buffer_dirty(leaf);
 704
 705	btrfs_release_path(path);
 706
 707	key.type = BTRFS_QGROUP_LIMIT_KEY;
 708	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 709				      sizeof(*qgroup_limit));
 710	if (ret && ret != -EEXIST)
 711		goto out;
 712
 713	leaf = path->nodes[0];
 714	qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
 715				  struct btrfs_qgroup_limit_item);
 716	btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
 717	btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
 718	btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
 719	btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
 720	btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
 721
 722	btrfs_mark_buffer_dirty(leaf);
 723
 724	ret = 0;
 725out:
 726	btrfs_free_path(path);
 727	return ret;
 728}
 729
 730static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid)
 
 731{
 732	int ret;
 733	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 734	struct btrfs_path *path;
 735	struct btrfs_key key;
 736
 737	path = btrfs_alloc_path();
 738	if (!path)
 739		return -ENOMEM;
 740
 741	key.objectid = 0;
 742	key.type = BTRFS_QGROUP_INFO_KEY;
 743	key.offset = qgroupid;
 744	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 745	if (ret < 0)
 746		goto out;
 747
 748	if (ret > 0) {
 749		ret = -ENOENT;
 750		goto out;
 751	}
 752
 753	ret = btrfs_del_item(trans, quota_root, path);
 754	if (ret)
 755		goto out;
 756
 757	btrfs_release_path(path);
 758
 759	key.type = BTRFS_QGROUP_LIMIT_KEY;
 760	ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
 761	if (ret < 0)
 762		goto out;
 763
 764	if (ret > 0) {
 765		ret = -ENOENT;
 766		goto out;
 767	}
 768
 769	ret = btrfs_del_item(trans, quota_root, path);
 770
 771out:
 772	btrfs_free_path(path);
 773	return ret;
 774}
 775
 776static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
 
 777				    struct btrfs_qgroup *qgroup)
 778{
 779	struct btrfs_root *quota_root = trans->fs_info->quota_root;
 780	struct btrfs_path *path;
 781	struct btrfs_key key;
 782	struct extent_buffer *l;
 783	struct btrfs_qgroup_limit_item *qgroup_limit;
 784	int ret;
 785	int slot;
 786
 787	key.objectid = 0;
 788	key.type = BTRFS_QGROUP_LIMIT_KEY;
 789	key.offset = qgroup->qgroupid;
 790
 791	path = btrfs_alloc_path();
 792	if (!path)
 793		return -ENOMEM;
 794
 795	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 796	if (ret > 0)
 797		ret = -ENOENT;
 798
 799	if (ret)
 800		goto out;
 801
 802	l = path->nodes[0];
 803	slot = path->slots[0];
 804	qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
 805	btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
 806	btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
 807	btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
 808	btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
 809	btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
 810
 811	btrfs_mark_buffer_dirty(l);
 812
 813out:
 814	btrfs_free_path(path);
 815	return ret;
 816}
 817
 818static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
 
 819				   struct btrfs_qgroup *qgroup)
 820{
 821	struct btrfs_fs_info *fs_info = trans->fs_info;
 822	struct btrfs_root *quota_root = fs_info->quota_root;
 823	struct btrfs_path *path;
 824	struct btrfs_key key;
 825	struct extent_buffer *l;
 826	struct btrfs_qgroup_info_item *qgroup_info;
 827	int ret;
 828	int slot;
 829
 830	if (btrfs_is_testing(fs_info))
 831		return 0;
 832
 833	key.objectid = 0;
 834	key.type = BTRFS_QGROUP_INFO_KEY;
 835	key.offset = qgroup->qgroupid;
 836
 837	path = btrfs_alloc_path();
 838	if (!path)
 839		return -ENOMEM;
 840
 841	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 842	if (ret > 0)
 843		ret = -ENOENT;
 844
 845	if (ret)
 846		goto out;
 847
 848	l = path->nodes[0];
 849	slot = path->slots[0];
 850	qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 851	btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 852	btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 853	btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 854	btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 855	btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 856
 857	btrfs_mark_buffer_dirty(l);
 858
 859out:
 860	btrfs_free_path(path);
 861	return ret;
 862}
 863
 864static int update_qgroup_status_item(struct btrfs_trans_handle *trans)
 
 
 865{
 866	struct btrfs_fs_info *fs_info = trans->fs_info;
 867	struct btrfs_root *quota_root = fs_info->quota_root;
 868	struct btrfs_path *path;
 869	struct btrfs_key key;
 870	struct extent_buffer *l;
 871	struct btrfs_qgroup_status_item *ptr;
 872	int ret;
 873	int slot;
 874
 875	key.objectid = 0;
 876	key.type = BTRFS_QGROUP_STATUS_KEY;
 877	key.offset = 0;
 878
 879	path = btrfs_alloc_path();
 880	if (!path)
 881		return -ENOMEM;
 882
 883	ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1);
 884	if (ret > 0)
 885		ret = -ENOENT;
 886
 887	if (ret)
 888		goto out;
 889
 890	l = path->nodes[0];
 891	slot = path->slots[0];
 892	ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 893	btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags &
 894				      BTRFS_QGROUP_STATUS_FLAGS_MASK);
 895	btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 896	btrfs_set_qgroup_status_rescan(l, ptr,
 897				fs_info->qgroup_rescan_progress.objectid);
 898
 899	btrfs_mark_buffer_dirty(l);
 900
 901out:
 902	btrfs_free_path(path);
 903	return ret;
 904}
 905
 906/*
 907 * called with qgroup_lock held
 908 */
 909static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 910				  struct btrfs_root *root)
 911{
 912	struct btrfs_path *path;
 913	struct btrfs_key key;
 914	struct extent_buffer *leaf = NULL;
 915	int ret;
 916	int nr = 0;
 917
 918	path = btrfs_alloc_path();
 919	if (!path)
 920		return -ENOMEM;
 921
 
 
 922	key.objectid = 0;
 923	key.offset = 0;
 924	key.type = 0;
 925
 926	while (1) {
 927		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 928		if (ret < 0)
 929			goto out;
 930		leaf = path->nodes[0];
 931		nr = btrfs_header_nritems(leaf);
 932		if (!nr)
 933			break;
 934		/*
 935		 * delete the leaf one by one
 936		 * since the whole tree is going
 937		 * to be deleted.
 938		 */
 939		path->slots[0] = 0;
 940		ret = btrfs_del_items(trans, root, path, 0, nr);
 941		if (ret)
 942			goto out;
 943
 944		btrfs_release_path(path);
 945	}
 946	ret = 0;
 947out:
 948	btrfs_free_path(path);
 949	return ret;
 950}
 951
 952int btrfs_quota_enable(struct btrfs_fs_info *fs_info)
 
 953{
 954	struct btrfs_root *quota_root;
 955	struct btrfs_root *tree_root = fs_info->tree_root;
 956	struct btrfs_path *path = NULL;
 957	struct btrfs_qgroup_status_item *ptr;
 958	struct extent_buffer *leaf;
 959	struct btrfs_key key;
 960	struct btrfs_key found_key;
 961	struct btrfs_qgroup *qgroup = NULL;
 962	struct btrfs_trans_handle *trans = NULL;
 963	struct ulist *ulist = NULL;
 964	int ret = 0;
 965	int slot;
 966
 967	/*
 968	 * We need to have subvol_sem write locked, to prevent races between
 969	 * concurrent tasks trying to enable quotas, because we will unlock
 970	 * and relock qgroup_ioctl_lock before setting fs_info->quota_root
 971	 * and before setting BTRFS_FS_QUOTA_ENABLED.
 972	 */
 973	lockdep_assert_held_write(&fs_info->subvol_sem);
 974
 975	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
 976		btrfs_err(fs_info,
 977			  "qgroups are currently unsupported in extent tree v2");
 978		return -EINVAL;
 979	}
 980
 981	mutex_lock(&fs_info->qgroup_ioctl_lock);
 982	if (fs_info->quota_root)
 983		goto out;
 984
 985	ulist = ulist_alloc(GFP_KERNEL);
 986	if (!ulist) {
 987		ret = -ENOMEM;
 988		goto out;
 989	}
 990
 991	ret = btrfs_sysfs_add_qgroups(fs_info);
 992	if (ret < 0)
 993		goto out;
 994
 995	/*
 996	 * Unlock qgroup_ioctl_lock before starting the transaction. This is to
 997	 * avoid lock acquisition inversion problems (reported by lockdep) between
 998	 * qgroup_ioctl_lock and the vfs freeze semaphores, acquired when we
 999	 * start a transaction.
1000	 * After we started the transaction lock qgroup_ioctl_lock again and
1001	 * check if someone else created the quota root in the meanwhile. If so,
1002	 * just return success and release the transaction handle.
1003	 *
1004	 * Also we don't need to worry about someone else calling
1005	 * btrfs_sysfs_add_qgroups() after we unlock and getting an error because
1006	 * that function returns 0 (success) when the sysfs entries already exist.
1007	 */
1008	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1009
1010	/*
1011	 * 1 for quota root item
1012	 * 1 for BTRFS_QGROUP_STATUS item
1013	 *
1014	 * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items
1015	 * per subvolume. However those are not currently reserved since it
1016	 * would be a lot of overkill.
1017	 */
1018	trans = btrfs_start_transaction(tree_root, 2);
1019
1020	mutex_lock(&fs_info->qgroup_ioctl_lock);
1021	if (IS_ERR(trans)) {
1022		ret = PTR_ERR(trans);
1023		trans = NULL;
1024		goto out;
1025	}
1026
1027	if (fs_info->quota_root)
1028		goto out;
1029
1030	fs_info->qgroup_ulist = ulist;
1031	ulist = NULL;
1032
1033	/*
1034	 * initially create the quota tree
1035	 */
1036	quota_root = btrfs_create_tree(trans, BTRFS_QUOTA_TREE_OBJECTID);
 
1037	if (IS_ERR(quota_root)) {
1038		ret =  PTR_ERR(quota_root);
1039		btrfs_abort_transaction(trans, ret);
1040		goto out;
1041	}
1042
1043	path = btrfs_alloc_path();
1044	if (!path) {
1045		ret = -ENOMEM;
1046		btrfs_abort_transaction(trans, ret);
1047		goto out_free_root;
1048	}
1049
1050	key.objectid = 0;
1051	key.type = BTRFS_QGROUP_STATUS_KEY;
1052	key.offset = 0;
1053
1054	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
1055				      sizeof(*ptr));
1056	if (ret) {
1057		btrfs_abort_transaction(trans, ret);
1058		goto out_free_path;
1059	}
1060
1061	leaf = path->nodes[0];
1062	ptr = btrfs_item_ptr(leaf, path->slots[0],
1063				 struct btrfs_qgroup_status_item);
1064	btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
1065	btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
1066	fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
1067				BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1068	btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags &
1069				      BTRFS_QGROUP_STATUS_FLAGS_MASK);
1070	btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
1071
1072	btrfs_mark_buffer_dirty(leaf);
1073
1074	key.objectid = 0;
1075	key.type = BTRFS_ROOT_REF_KEY;
1076	key.offset = 0;
1077
1078	btrfs_release_path(path);
1079	ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
1080	if (ret > 0)
1081		goto out_add_root;
1082	if (ret < 0) {
1083		btrfs_abort_transaction(trans, ret);
1084		goto out_free_path;
1085	}
1086
1087	while (1) {
1088		slot = path->slots[0];
1089		leaf = path->nodes[0];
1090		btrfs_item_key_to_cpu(leaf, &found_key, slot);
1091
1092		if (found_key.type == BTRFS_ROOT_REF_KEY) {
1093
1094			/* Release locks on tree_root before we access quota_root */
1095			btrfs_release_path(path);
1096
1097			ret = add_qgroup_item(trans, quota_root,
1098					      found_key.offset);
1099			if (ret) {
1100				btrfs_abort_transaction(trans, ret);
1101				goto out_free_path;
1102			}
1103
1104			qgroup = add_qgroup_rb(fs_info, found_key.offset);
1105			if (IS_ERR(qgroup)) {
1106				ret = PTR_ERR(qgroup);
1107				btrfs_abort_transaction(trans, ret);
1108				goto out_free_path;
1109			}
1110			ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1111			if (ret < 0) {
1112				btrfs_abort_transaction(trans, ret);
1113				goto out_free_path;
1114			}
1115			ret = btrfs_search_slot_for_read(tree_root, &found_key,
1116							 path, 1, 0);
1117			if (ret < 0) {
1118				btrfs_abort_transaction(trans, ret);
1119				goto out_free_path;
1120			}
1121			if (ret > 0) {
1122				/*
1123				 * Shouldn't happen, but in case it does we
1124				 * don't need to do the btrfs_next_item, just
1125				 * continue.
1126				 */
1127				continue;
1128			}
1129		}
1130		ret = btrfs_next_item(tree_root, path);
1131		if (ret < 0) {
1132			btrfs_abort_transaction(trans, ret);
1133			goto out_free_path;
1134		}
1135		if (ret)
1136			break;
1137	}
1138
1139out_add_root:
1140	btrfs_release_path(path);
1141	ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
1142	if (ret) {
1143		btrfs_abort_transaction(trans, ret);
1144		goto out_free_path;
1145	}
1146
1147	qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
1148	if (IS_ERR(qgroup)) {
1149		ret = PTR_ERR(qgroup);
1150		btrfs_abort_transaction(trans, ret);
1151		goto out_free_path;
1152	}
1153	ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1154	if (ret < 0) {
1155		btrfs_abort_transaction(trans, ret);
1156		goto out_free_path;
1157	}
1158
1159	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1160	/*
1161	 * Commit the transaction while not holding qgroup_ioctl_lock, to avoid
1162	 * a deadlock with tasks concurrently doing other qgroup operations, such
1163	 * adding/removing qgroups or adding/deleting qgroup relations for example,
1164	 * because all qgroup operations first start or join a transaction and then
1165	 * lock the qgroup_ioctl_lock mutex.
1166	 * We are safe from a concurrent task trying to enable quotas, by calling
1167	 * this function, since we are serialized by fs_info->subvol_sem.
1168	 */
1169	ret = btrfs_commit_transaction(trans);
1170	trans = NULL;
1171	mutex_lock(&fs_info->qgroup_ioctl_lock);
1172	if (ret)
1173		goto out_free_path;
1174
1175	/*
1176	 * Set quota enabled flag after committing the transaction, to avoid
1177	 * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot
1178	 * creation.
1179	 */
1180	spin_lock(&fs_info->qgroup_lock);
1181	fs_info->quota_root = quota_root;
1182	set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1183	spin_unlock(&fs_info->qgroup_lock);
1184
1185	ret = qgroup_rescan_init(fs_info, 0, 1);
1186	if (!ret) {
1187	        qgroup_rescan_zero_tracking(fs_info);
1188		fs_info->qgroup_rescan_running = true;
1189	        btrfs_queue_work(fs_info->qgroup_rescan_workers,
1190	                         &fs_info->qgroup_rescan_work);
1191	} else {
1192		/*
1193		 * We have set both BTRFS_FS_QUOTA_ENABLED and
1194		 * BTRFS_QGROUP_STATUS_FLAG_ON, so we can only fail with
1195		 * -EINPROGRESS. That can happen because someone started the
1196		 * rescan worker by calling quota rescan ioctl before we
1197		 * attempted to initialize the rescan worker. Failure due to
1198		 * quotas disabled in the meanwhile is not possible, because
1199		 * we are holding a write lock on fs_info->subvol_sem, which
1200		 * is also acquired when disabling quotas.
1201		 * Ignore such error, and any other error would need to undo
1202		 * everything we did in the transaction we just committed.
1203		 */
1204		ASSERT(ret == -EINPROGRESS);
1205		ret = 0;
1206	}
1207
1208out_free_path:
1209	btrfs_free_path(path);
1210out_free_root:
1211	if (ret)
1212		btrfs_put_root(quota_root);
 
 
 
1213out:
1214	if (ret) {
1215		ulist_free(fs_info->qgroup_ulist);
1216		fs_info->qgroup_ulist = NULL;
1217		btrfs_sysfs_del_qgroups(fs_info);
1218	}
1219	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1220	if (ret && trans)
1221		btrfs_end_transaction(trans);
1222	else if (trans)
1223		ret = btrfs_end_transaction(trans);
1224	ulist_free(ulist);
1225	return ret;
1226}
1227
1228int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
 
1229{
1230	struct btrfs_root *quota_root;
1231	struct btrfs_trans_handle *trans = NULL;
1232	int ret = 0;
1233
1234	/*
1235	 * We need to have subvol_sem write locked, to prevent races between
1236	 * concurrent tasks trying to disable quotas, because we will unlock
1237	 * and relock qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes.
1238	 */
1239	lockdep_assert_held_write(&fs_info->subvol_sem);
1240
1241	mutex_lock(&fs_info->qgroup_ioctl_lock);
1242	if (!fs_info->quota_root)
1243		goto out;
1244
1245	/*
1246	 * Unlock the qgroup_ioctl_lock mutex before waiting for the rescan worker to
1247	 * complete. Otherwise we can deadlock because btrfs_remove_qgroup() needs
1248	 * to lock that mutex while holding a transaction handle and the rescan
1249	 * worker needs to commit a transaction.
1250	 */
1251	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1252
1253	/*
1254	 * Request qgroup rescan worker to complete and wait for it. This wait
1255	 * must be done before transaction start for quota disable since it may
1256	 * deadlock with transaction by the qgroup rescan worker.
1257	 */
1258	clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1259	btrfs_qgroup_wait_for_completion(fs_info, false);
1260
1261	/*
1262	 * 1 For the root item
1263	 *
1264	 * We should also reserve enough items for the quota tree deletion in
1265	 * btrfs_clean_quota_tree but this is not done.
1266	 *
1267	 * Also, we must always start a transaction without holding the mutex
1268	 * qgroup_ioctl_lock, see btrfs_quota_enable().
1269	 */
1270	trans = btrfs_start_transaction(fs_info->tree_root, 1);
1271
1272	mutex_lock(&fs_info->qgroup_ioctl_lock);
1273	if (IS_ERR(trans)) {
1274		ret = PTR_ERR(trans);
1275		trans = NULL;
1276		set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1277		goto out;
1278	}
1279
1280	if (!fs_info->quota_root)
1281		goto out;
1282
1283	spin_lock(&fs_info->qgroup_lock);
1284	quota_root = fs_info->quota_root;
1285	fs_info->quota_root = NULL;
1286	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
1287	fs_info->qgroup_drop_subtree_thres = BTRFS_MAX_LEVEL;
1288	spin_unlock(&fs_info->qgroup_lock);
1289
1290	btrfs_free_qgroup_config(fs_info);
1291
1292	ret = btrfs_clean_quota_tree(trans, quota_root);
1293	if (ret) {
1294		btrfs_abort_transaction(trans, ret);
1295		goto out;
1296	}
1297
1298	ret = btrfs_del_root(trans, &quota_root->root_key);
1299	if (ret) {
1300		btrfs_abort_transaction(trans, ret);
1301		goto out;
1302	}
1303
1304	list_del(&quota_root->dirty_list);
1305
1306	btrfs_tree_lock(quota_root->node);
1307	btrfs_clean_tree_block(quota_root->node);
1308	btrfs_tree_unlock(quota_root->node);
1309	btrfs_free_tree_block(trans, btrfs_root_id(quota_root),
1310			      quota_root->node, 0, 1);
1311
1312	btrfs_put_root(quota_root);
1313
 
 
 
1314out:
1315	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1316	if (ret && trans)
1317		btrfs_end_transaction(trans);
1318	else if (trans)
1319		ret = btrfs_end_transaction(trans);
1320
1321	return ret;
1322}
1323
1324static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1325			 struct btrfs_qgroup *qgroup)
1326{
1327	if (list_empty(&qgroup->dirty))
1328		list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1329}
1330
1331/*
1332 * The easy accounting, we're updating qgroup relationship whose child qgroup
1333 * only has exclusive extents.
1334 *
1335 * In this case, all exclusive extents will also be exclusive for parent, so
1336 * excl/rfer just get added/removed.
1337 *
1338 * So is qgroup reservation space, which should also be added/removed to
1339 * parent.
1340 * Or when child tries to release reservation space, parent will underflow its
1341 * reservation (for relationship adding case).
1342 *
1343 * Caller should hold fs_info->qgroup_lock.
1344 */
1345static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1346				    struct ulist *tmp, u64 ref_root,
1347				    struct btrfs_qgroup *src, int sign)
1348{
1349	struct btrfs_qgroup *qgroup;
1350	struct btrfs_qgroup_list *glist;
1351	struct ulist_node *unode;
1352	struct ulist_iterator uiter;
1353	u64 num_bytes = src->excl;
1354	int ret = 0;
1355
1356	qgroup = find_qgroup_rb(fs_info, ref_root);
1357	if (!qgroup)
1358		goto out;
1359
1360	qgroup->rfer += sign * num_bytes;
1361	qgroup->rfer_cmpr += sign * num_bytes;
1362
1363	WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1364	qgroup->excl += sign * num_bytes;
1365	qgroup->excl_cmpr += sign * num_bytes;
1366
1367	if (sign > 0)
1368		qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1369	else
1370		qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1371
1372	qgroup_dirty(fs_info, qgroup);
1373
1374	/* Get all of the parent groups that contain this qgroup */
1375	list_for_each_entry(glist, &qgroup->groups, next_group) {
1376		ret = ulist_add(tmp, glist->group->qgroupid,
1377				qgroup_to_aux(glist->group), GFP_ATOMIC);
1378		if (ret < 0)
1379			goto out;
1380	}
1381
1382	/* Iterate all of the parents and adjust their reference counts */
1383	ULIST_ITER_INIT(&uiter);
1384	while ((unode = ulist_next(tmp, &uiter))) {
1385		qgroup = unode_aux_to_qgroup(unode);
1386		qgroup->rfer += sign * num_bytes;
1387		qgroup->rfer_cmpr += sign * num_bytes;
1388		WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1389		qgroup->excl += sign * num_bytes;
1390		if (sign > 0)
1391			qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1392		else
1393			qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1394		qgroup->excl_cmpr += sign * num_bytes;
1395		qgroup_dirty(fs_info, qgroup);
1396
1397		/* Add any parents of the parents */
1398		list_for_each_entry(glist, &qgroup->groups, next_group) {
1399			ret = ulist_add(tmp, glist->group->qgroupid,
1400					qgroup_to_aux(glist->group), GFP_ATOMIC);
1401			if (ret < 0)
1402				goto out;
1403		}
1404	}
1405	ret = 0;
1406out:
1407	return ret;
1408}
1409
1410
1411/*
1412 * Quick path for updating qgroup with only excl refs.
1413 *
1414 * In that case, just update all parent will be enough.
1415 * Or we needs to do a full rescan.
1416 * Caller should also hold fs_info->qgroup_lock.
1417 *
1418 * Return 0 for quick update, return >0 for need to full rescan
1419 * and mark INCONSISTENT flag.
1420 * Return < 0 for other error.
1421 */
1422static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1423				   struct ulist *tmp, u64 src, u64 dst,
1424				   int sign)
1425{
1426	struct btrfs_qgroup *qgroup;
1427	int ret = 1;
1428	int err = 0;
1429
1430	qgroup = find_qgroup_rb(fs_info, src);
1431	if (!qgroup)
1432		goto out;
1433	if (qgroup->excl == qgroup->rfer) {
1434		ret = 0;
1435		err = __qgroup_excl_accounting(fs_info, tmp, dst,
1436					       qgroup, sign);
1437		if (err < 0) {
1438			ret = err;
1439			goto out;
1440		}
1441	}
1442out:
1443	if (ret)
1444		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1445	return ret;
1446}
1447
1448int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1449			      u64 dst)
1450{
1451	struct btrfs_fs_info *fs_info = trans->fs_info;
1452	struct btrfs_qgroup *parent;
1453	struct btrfs_qgroup *member;
1454	struct btrfs_qgroup_list *list;
1455	struct ulist *tmp;
1456	unsigned int nofs_flag;
1457	int ret = 0;
1458
1459	/* Check the level of src and dst first */
1460	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1461		return -EINVAL;
1462
1463	/* We hold a transaction handle open, must do a NOFS allocation. */
1464	nofs_flag = memalloc_nofs_save();
1465	tmp = ulist_alloc(GFP_KERNEL);
1466	memalloc_nofs_restore(nofs_flag);
1467	if (!tmp)
1468		return -ENOMEM;
1469
1470	mutex_lock(&fs_info->qgroup_ioctl_lock);
1471	if (!fs_info->quota_root) {
1472		ret = -ENOTCONN;
 
1473		goto out;
1474	}
1475	member = find_qgroup_rb(fs_info, src);
1476	parent = find_qgroup_rb(fs_info, dst);
1477	if (!member || !parent) {
1478		ret = -EINVAL;
1479		goto out;
1480	}
1481
1482	/* check if such qgroup relation exist firstly */
1483	list_for_each_entry(list, &member->groups, next_group) {
1484		if (list->group == parent) {
1485			ret = -EEXIST;
1486			goto out;
1487		}
1488	}
1489
1490	ret = add_qgroup_relation_item(trans, src, dst);
1491	if (ret)
1492		goto out;
1493
1494	ret = add_qgroup_relation_item(trans, dst, src);
1495	if (ret) {
1496		del_qgroup_relation_item(trans, src, dst);
1497		goto out;
1498	}
1499
1500	spin_lock(&fs_info->qgroup_lock);
1501	ret = __add_relation_rb(member, parent);
1502	if (ret < 0) {
1503		spin_unlock(&fs_info->qgroup_lock);
1504		goto out;
1505	}
1506	ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1507	spin_unlock(&fs_info->qgroup_lock);
1508out:
1509	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1510	ulist_free(tmp);
1511	return ret;
1512}
1513
1514static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1515				 u64 dst)
1516{
1517	struct btrfs_fs_info *fs_info = trans->fs_info;
1518	struct btrfs_qgroup *parent;
1519	struct btrfs_qgroup *member;
1520	struct btrfs_qgroup_list *list;
1521	struct ulist *tmp;
1522	bool found = false;
1523	unsigned int nofs_flag;
1524	int ret = 0;
1525	int ret2;
1526
1527	/* We hold a transaction handle open, must do a NOFS allocation. */
1528	nofs_flag = memalloc_nofs_save();
1529	tmp = ulist_alloc(GFP_KERNEL);
1530	memalloc_nofs_restore(nofs_flag);
1531	if (!tmp)
1532		return -ENOMEM;
1533
1534	if (!fs_info->quota_root) {
1535		ret = -ENOTCONN;
 
1536		goto out;
1537	}
1538
1539	member = find_qgroup_rb(fs_info, src);
1540	parent = find_qgroup_rb(fs_info, dst);
1541	/*
1542	 * The parent/member pair doesn't exist, then try to delete the dead
1543	 * relation items only.
1544	 */
1545	if (!member || !parent)
1546		goto delete_item;
1547
1548	/* check if such qgroup relation exist firstly */
1549	list_for_each_entry(list, &member->groups, next_group) {
1550		if (list->group == parent) {
1551			found = true;
1552			break;
1553		}
1554	}
 
 
 
 
 
 
 
1555
1556delete_item:
1557	ret = del_qgroup_relation_item(trans, src, dst);
1558	if (ret < 0 && ret != -ENOENT)
1559		goto out;
1560	ret2 = del_qgroup_relation_item(trans, dst, src);
1561	if (ret2 < 0 && ret2 != -ENOENT)
1562		goto out;
1563
1564	/* At least one deletion succeeded, return 0 */
1565	if (!ret || !ret2)
1566		ret = 0;
1567
1568	if (found) {
1569		spin_lock(&fs_info->qgroup_lock);
1570		del_relation_rb(fs_info, src, dst);
1571		ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1572		spin_unlock(&fs_info->qgroup_lock);
1573	}
1574out:
1575	ulist_free(tmp);
1576	return ret;
1577}
1578
1579int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
1580			      u64 dst)
1581{
1582	struct btrfs_fs_info *fs_info = trans->fs_info;
1583	int ret = 0;
1584
1585	mutex_lock(&fs_info->qgroup_ioctl_lock);
1586	ret = __del_qgroup_relation(trans, src, dst);
1587	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1588
1589	return ret;
1590}
1591
1592int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 
1593{
1594	struct btrfs_fs_info *fs_info = trans->fs_info;
1595	struct btrfs_root *quota_root;
1596	struct btrfs_qgroup *qgroup;
1597	int ret = 0;
1598
1599	mutex_lock(&fs_info->qgroup_ioctl_lock);
1600	if (!fs_info->quota_root) {
1601		ret = -ENOTCONN;
 
1602		goto out;
1603	}
1604	quota_root = fs_info->quota_root;
1605	qgroup = find_qgroup_rb(fs_info, qgroupid);
1606	if (qgroup) {
1607		ret = -EEXIST;
1608		goto out;
1609	}
1610
1611	ret = add_qgroup_item(trans, quota_root, qgroupid);
1612	if (ret)
1613		goto out;
1614
1615	spin_lock(&fs_info->qgroup_lock);
1616	qgroup = add_qgroup_rb(fs_info, qgroupid);
1617	spin_unlock(&fs_info->qgroup_lock);
1618
1619	if (IS_ERR(qgroup)) {
1620		ret = PTR_ERR(qgroup);
1621		goto out;
1622	}
1623	ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup);
1624out:
1625	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1626	return ret;
1627}
1628
1629int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid)
 
1630{
1631	struct btrfs_fs_info *fs_info = trans->fs_info;
1632	struct btrfs_qgroup *qgroup;
1633	struct btrfs_qgroup_list *list;
1634	int ret = 0;
1635
1636	mutex_lock(&fs_info->qgroup_ioctl_lock);
1637	if (!fs_info->quota_root) {
1638		ret = -ENOTCONN;
 
1639		goto out;
1640	}
1641
1642	qgroup = find_qgroup_rb(fs_info, qgroupid);
1643	if (!qgroup) {
1644		ret = -ENOENT;
1645		goto out;
 
 
 
 
 
 
1646	}
1647
1648	/* Check if there are no children of this qgroup */
1649	if (!list_empty(&qgroup->members)) {
1650		ret = -EBUSY;
1651		goto out;
1652	}
1653
1654	ret = del_qgroup_item(trans, qgroupid);
1655	if (ret && ret != -ENOENT)
1656		goto out;
1657
1658	while (!list_empty(&qgroup->groups)) {
1659		list = list_first_entry(&qgroup->groups,
1660					struct btrfs_qgroup_list, next_group);
1661		ret = __del_qgroup_relation(trans, qgroupid,
1662					    list->group->qgroupid);
 
1663		if (ret)
1664			goto out;
1665	}
1666
1667	spin_lock(&fs_info->qgroup_lock);
1668	del_qgroup_rb(fs_info, qgroupid);
1669	spin_unlock(&fs_info->qgroup_lock);
1670
1671	/*
1672	 * Remove the qgroup from sysfs now without holding the qgroup_lock
1673	 * spinlock, since the sysfs_remove_group() function needs to take
1674	 * the mutex kernfs_mutex through kernfs_remove_by_name_ns().
1675	 */
1676	btrfs_sysfs_del_one_qgroup(fs_info, qgroup);
1677	kfree(qgroup);
1678out:
1679	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1680	return ret;
1681}
1682
1683int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
 
1684		       struct btrfs_qgroup_limit *limit)
1685{
1686	struct btrfs_fs_info *fs_info = trans->fs_info;
1687	struct btrfs_qgroup *qgroup;
1688	int ret = 0;
1689	/* Sometimes we would want to clear the limit on this qgroup.
1690	 * To meet this requirement, we treat the -1 as a special value
1691	 * which tell kernel to clear the limit on this qgroup.
1692	 */
1693	const u64 CLEAR_VALUE = -1;
1694
1695	mutex_lock(&fs_info->qgroup_ioctl_lock);
1696	if (!fs_info->quota_root) {
1697		ret = -ENOTCONN;
 
1698		goto out;
1699	}
1700
1701	qgroup = find_qgroup_rb(fs_info, qgroupid);
1702	if (!qgroup) {
1703		ret = -ENOENT;
1704		goto out;
1705	}
1706
1707	spin_lock(&fs_info->qgroup_lock);
1708	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1709		if (limit->max_rfer == CLEAR_VALUE) {
1710			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1711			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1712			qgroup->max_rfer = 0;
1713		} else {
1714			qgroup->max_rfer = limit->max_rfer;
1715		}
1716	}
1717	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1718		if (limit->max_excl == CLEAR_VALUE) {
1719			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1720			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1721			qgroup->max_excl = 0;
1722		} else {
1723			qgroup->max_excl = limit->max_excl;
1724		}
1725	}
1726	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1727		if (limit->rsv_rfer == CLEAR_VALUE) {
1728			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1729			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1730			qgroup->rsv_rfer = 0;
1731		} else {
1732			qgroup->rsv_rfer = limit->rsv_rfer;
1733		}
1734	}
1735	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1736		if (limit->rsv_excl == CLEAR_VALUE) {
1737			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1738			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1739			qgroup->rsv_excl = 0;
1740		} else {
1741			qgroup->rsv_excl = limit->rsv_excl;
1742		}
1743	}
1744	qgroup->lim_flags |= limit->flags;
1745
1746	spin_unlock(&fs_info->qgroup_lock);
1747
1748	ret = update_qgroup_limit_item(trans, qgroup);
1749	if (ret) {
1750		qgroup_mark_inconsistent(fs_info);
1751		btrfs_info(fs_info, "unable to update quota limit for %llu",
1752		       qgroupid);
1753	}
1754
1755out:
1756	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1757	return ret;
1758}
1759
1760int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1761				struct btrfs_delayed_ref_root *delayed_refs,
1762				struct btrfs_qgroup_extent_record *record)
1763{
1764	struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1765	struct rb_node *parent_node = NULL;
1766	struct btrfs_qgroup_extent_record *entry;
1767	u64 bytenr = record->bytenr;
1768
1769	lockdep_assert_held(&delayed_refs->lock);
1770	trace_btrfs_qgroup_trace_extent(fs_info, record);
1771
1772	while (*p) {
1773		parent_node = *p;
1774		entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1775				 node);
1776		if (bytenr < entry->bytenr) {
1777			p = &(*p)->rb_left;
1778		} else if (bytenr > entry->bytenr) {
1779			p = &(*p)->rb_right;
1780		} else {
1781			if (record->data_rsv && !entry->data_rsv) {
1782				entry->data_rsv = record->data_rsv;
1783				entry->data_rsv_refroot =
1784					record->data_rsv_refroot;
1785			}
1786			return 1;
1787		}
1788	}
1789
1790	rb_link_node(&record->node, parent_node, p);
1791	rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1792	return 0;
1793}
1794
1795int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans,
1796				   struct btrfs_qgroup_extent_record *qrecord)
1797{
1798	struct btrfs_backref_walk_ctx ctx = { 0 };
 
1799	int ret;
1800
1801	/*
1802	 * We are always called in a context where we are already holding a
1803	 * transaction handle. Often we are called when adding a data delayed
1804	 * reference from btrfs_truncate_inode_items() (truncating or unlinking),
1805	 * in which case we will be holding a write lock on extent buffer from a
1806	 * subvolume tree. In this case we can't allow btrfs_find_all_roots() to
1807	 * acquire fs_info->commit_root_sem, because that is a higher level lock
1808	 * that must be acquired before locking any extent buffers.
1809	 *
1810	 * So we want btrfs_find_all_roots() to not acquire the commit_root_sem
1811	 * but we can't pass it a non-NULL transaction handle, because otherwise
1812	 * it would not use commit roots and would lock extent buffers, causing
1813	 * a deadlock if it ends up trying to read lock the same extent buffer
1814	 * that was previously write locked at btrfs_truncate_inode_items().
1815	 *
1816	 * So pass a NULL transaction handle to btrfs_find_all_roots() and
1817	 * explicitly tell it to not acquire the commit_root_sem - if we are
1818	 * holding a transaction handle we don't need its protection.
1819	 */
1820	ASSERT(trans != NULL);
1821
1822	if (trans->fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
1823		return 0;
1824
1825	ctx.bytenr = qrecord->bytenr;
1826	ctx.fs_info = trans->fs_info;
1827
1828	ret = btrfs_find_all_roots(&ctx, true);
1829	if (ret < 0) {
1830		qgroup_mark_inconsistent(trans->fs_info);
1831		btrfs_warn(trans->fs_info,
1832"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1833			ret);
1834		return 0;
1835	}
1836
1837	/*
1838	 * Here we don't need to get the lock of
1839	 * trans->transaction->delayed_refs, since inserted qrecord won't
1840	 * be deleted, only qrecord->node may be modified (new qrecord insert)
1841	 *
1842	 * So modifying qrecord->old_roots is safe here
1843	 */
1844	qrecord->old_roots = ctx.roots;
1845	return 0;
1846}
1847
1848int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
1849			      u64 num_bytes)
 
1850{
1851	struct btrfs_fs_info *fs_info = trans->fs_info;
1852	struct btrfs_qgroup_extent_record *record;
1853	struct btrfs_delayed_ref_root *delayed_refs;
1854	int ret;
1855
1856	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)
1857	    || bytenr == 0 || num_bytes == 0)
1858		return 0;
1859	record = kzalloc(sizeof(*record), GFP_NOFS);
 
 
1860	if (!record)
1861		return -ENOMEM;
1862
1863	delayed_refs = &trans->transaction->delayed_refs;
1864	record->bytenr = bytenr;
1865	record->num_bytes = num_bytes;
1866	record->old_roots = NULL;
1867
1868	spin_lock(&delayed_refs->lock);
1869	ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
1870	spin_unlock(&delayed_refs->lock);
1871	if (ret > 0) {
1872		kfree(record);
1873		return 0;
1874	}
1875	return btrfs_qgroup_trace_extent_post(trans, record);
1876}
1877
1878int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
 
1879				  struct extent_buffer *eb)
1880{
1881	struct btrfs_fs_info *fs_info = trans->fs_info;
1882	int nr = btrfs_header_nritems(eb);
1883	int i, extent_type, ret;
1884	struct btrfs_key key;
1885	struct btrfs_file_extent_item *fi;
1886	u64 bytenr, num_bytes;
1887
1888	/* We can be called directly from walk_up_proc() */
1889	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1890		return 0;
1891
1892	for (i = 0; i < nr; i++) {
1893		btrfs_item_key_to_cpu(eb, &key, i);
1894
1895		if (key.type != BTRFS_EXTENT_DATA_KEY)
1896			continue;
1897
1898		fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
1899		/* filter out non qgroup-accountable extents  */
1900		extent_type = btrfs_file_extent_type(eb, fi);
1901
1902		if (extent_type == BTRFS_FILE_EXTENT_INLINE)
1903			continue;
1904
1905		bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
1906		if (!bytenr)
1907			continue;
1908
1909		num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
1910
1911		ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes);
 
1912		if (ret)
1913			return ret;
1914	}
1915	cond_resched();
1916	return 0;
1917}
1918
1919/*
1920 * Walk up the tree from the bottom, freeing leaves and any interior
1921 * nodes which have had all slots visited. If a node (leaf or
1922 * interior) is freed, the node above it will have it's slot
1923 * incremented. The root node will never be freed.
1924 *
1925 * At the end of this function, we should have a path which has all
1926 * slots incremented to the next position for a search. If we need to
1927 * read a new node it will be NULL and the node above it will have the
1928 * correct slot selected for a later read.
1929 *
1930 * If we increment the root nodes slot counter past the number of
1931 * elements, 1 is returned to signal completion of the search.
1932 */
1933static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
1934{
1935	int level = 0;
1936	int nr, slot;
1937	struct extent_buffer *eb;
1938
1939	if (root_level == 0)
1940		return 1;
1941
1942	while (level <= root_level) {
1943		eb = path->nodes[level];
1944		nr = btrfs_header_nritems(eb);
1945		path->slots[level]++;
1946		slot = path->slots[level];
1947		if (slot >= nr || level == 0) {
1948			/*
1949			 * Don't free the root -  we will detect this
1950			 * condition after our loop and return a
1951			 * positive value for caller to stop walking the tree.
1952			 */
1953			if (level != root_level) {
1954				btrfs_tree_unlock_rw(eb, path->locks[level]);
1955				path->locks[level] = 0;
1956
1957				free_extent_buffer(eb);
1958				path->nodes[level] = NULL;
1959				path->slots[level] = 0;
1960			}
1961		} else {
1962			/*
1963			 * We have a valid slot to walk back down
1964			 * from. Stop here so caller can process these
1965			 * new nodes.
1966			 */
1967			break;
1968		}
1969
1970		level++;
1971	}
1972
1973	eb = path->nodes[root_level];
1974	if (path->slots[root_level] >= btrfs_header_nritems(eb))
1975		return 1;
1976
1977	return 0;
1978}
1979
1980/*
1981 * Helper function to trace a subtree tree block swap.
1982 *
1983 * The swap will happen in highest tree block, but there may be a lot of
1984 * tree blocks involved.
1985 *
1986 * For example:
1987 *  OO = Old tree blocks
1988 *  NN = New tree blocks allocated during balance
1989 *
1990 *           File tree (257)                  Reloc tree for 257
1991 * L2              OO                                NN
1992 *               /    \                            /    \
1993 * L1          OO      OO (a)                    OO      NN (a)
1994 *            / \     / \                       / \     / \
1995 * L0       OO   OO OO   OO                   OO   OO NN   NN
1996 *                  (b)  (c)                          (b)  (c)
1997 *
1998 * When calling qgroup_trace_extent_swap(), we will pass:
1999 * @src_eb = OO(a)
2000 * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
2001 * @dst_level = 0
2002 * @root_level = 1
2003 *
2004 * In that case, qgroup_trace_extent_swap() will search from OO(a) to
2005 * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.
2006 *
2007 * The main work of qgroup_trace_extent_swap() can be split into 3 parts:
2008 *
2009 * 1) Tree search from @src_eb
2010 *    It should acts as a simplified btrfs_search_slot().
2011 *    The key for search can be extracted from @dst_path->nodes[dst_level]
2012 *    (first key).
2013 *
2014 * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
2015 *    NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
2016 *    They should be marked during previous (@dst_level = 1) iteration.
2017 *
2018 * 3) Mark file extents in leaves dirty
2019 *    We don't have good way to pick out new file extents only.
2020 *    So we still follow the old method by scanning all file extents in
2021 *    the leave.
2022 *
2023 * This function can free us from keeping two paths, thus later we only need
2024 * to care about how to iterate all new tree blocks in reloc tree.
2025 */
2026static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans,
2027				    struct extent_buffer *src_eb,
2028				    struct btrfs_path *dst_path,
2029				    int dst_level, int root_level,
2030				    bool trace_leaf)
2031{
2032	struct btrfs_key key;
2033	struct btrfs_path *src_path;
2034	struct btrfs_fs_info *fs_info = trans->fs_info;
2035	u32 nodesize = fs_info->nodesize;
2036	int cur_level = root_level;
2037	int ret;
2038
2039	BUG_ON(dst_level > root_level);
2040	/* Level mismatch */
2041	if (btrfs_header_level(src_eb) != root_level)
2042		return -EINVAL;
2043
2044	src_path = btrfs_alloc_path();
2045	if (!src_path) {
2046		ret = -ENOMEM;
2047		goto out;
2048	}
2049
2050	if (dst_level)
2051		btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2052	else
2053		btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0);
2054
2055	/* For src_path */
2056	atomic_inc(&src_eb->refs);
2057	src_path->nodes[root_level] = src_eb;
2058	src_path->slots[root_level] = dst_path->slots[root_level];
2059	src_path->locks[root_level] = 0;
2060
2061	/* A simplified version of btrfs_search_slot() */
2062	while (cur_level >= dst_level) {
2063		struct btrfs_key src_key;
2064		struct btrfs_key dst_key;
2065
2066		if (src_path->nodes[cur_level] == NULL) {
2067			struct extent_buffer *eb;
2068			int parent_slot;
2069
2070			eb = src_path->nodes[cur_level + 1];
2071			parent_slot = src_path->slots[cur_level + 1];
2072
2073			eb = btrfs_read_node_slot(eb, parent_slot);
2074			if (IS_ERR(eb)) {
2075				ret = PTR_ERR(eb);
2076				goto out;
2077			}
2078
2079			src_path->nodes[cur_level] = eb;
2080
2081			btrfs_tree_read_lock(eb);
2082			src_path->locks[cur_level] = BTRFS_READ_LOCK;
2083		}
2084
2085		src_path->slots[cur_level] = dst_path->slots[cur_level];
2086		if (cur_level) {
2087			btrfs_node_key_to_cpu(dst_path->nodes[cur_level],
2088					&dst_key, dst_path->slots[cur_level]);
2089			btrfs_node_key_to_cpu(src_path->nodes[cur_level],
2090					&src_key, src_path->slots[cur_level]);
2091		} else {
2092			btrfs_item_key_to_cpu(dst_path->nodes[cur_level],
2093					&dst_key, dst_path->slots[cur_level]);
2094			btrfs_item_key_to_cpu(src_path->nodes[cur_level],
2095					&src_key, src_path->slots[cur_level]);
2096		}
2097		/* Content mismatch, something went wrong */
2098		if (btrfs_comp_cpu_keys(&dst_key, &src_key)) {
2099			ret = -ENOENT;
2100			goto out;
2101		}
2102		cur_level--;
2103	}
2104
2105	/*
2106	 * Now both @dst_path and @src_path have been populated, record the tree
2107	 * blocks for qgroup accounting.
2108	 */
2109	ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start,
2110					nodesize);
2111	if (ret < 0)
2112		goto out;
2113	ret = btrfs_qgroup_trace_extent(trans, dst_path->nodes[dst_level]->start,
2114					nodesize);
2115	if (ret < 0)
2116		goto out;
2117
2118	/* Record leaf file extents */
2119	if (dst_level == 0 && trace_leaf) {
2120		ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]);
2121		if (ret < 0)
2122			goto out;
2123		ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]);
2124	}
2125out:
2126	btrfs_free_path(src_path);
2127	return ret;
2128}
2129
2130/*
2131 * Helper function to do recursive generation-aware depth-first search, to
2132 * locate all new tree blocks in a subtree of reloc tree.
2133 *
2134 * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot)
2135 *         reloc tree
2136 * L2         NN (a)
2137 *          /    \
2138 * L1    OO        NN (b)
2139 *      /  \      /  \
2140 * L0  OO  OO    OO  NN
2141 *               (c) (d)
2142 * If we pass:
2143 * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ],
2144 * @cur_level = 1
2145 * @root_level = 1
2146 *
2147 * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace
2148 * above tree blocks along with their counter parts in file tree.
2149 * While during search, old tree blocks OO(c) will be skipped as tree block swap
2150 * won't affect OO(c).
2151 */
2152static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans,
2153					   struct extent_buffer *src_eb,
2154					   struct btrfs_path *dst_path,
2155					   int cur_level, int root_level,
2156					   u64 last_snapshot, bool trace_leaf)
2157{
2158	struct btrfs_fs_info *fs_info = trans->fs_info;
2159	struct extent_buffer *eb;
2160	bool need_cleanup = false;
2161	int ret = 0;
2162	int i;
2163
2164	/* Level sanity check */
2165	if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 ||
2166	    root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 ||
2167	    root_level < cur_level) {
2168		btrfs_err_rl(fs_info,
2169			"%s: bad levels, cur_level=%d root_level=%d",
2170			__func__, cur_level, root_level);
2171		return -EUCLEAN;
2172	}
2173
2174	/* Read the tree block if needed */
2175	if (dst_path->nodes[cur_level] == NULL) {
2176		int parent_slot;
2177		u64 child_gen;
2178
2179		/*
2180		 * dst_path->nodes[root_level] must be initialized before
2181		 * calling this function.
2182		 */
2183		if (cur_level == root_level) {
2184			btrfs_err_rl(fs_info,
2185	"%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d",
2186				__func__, root_level, root_level, cur_level);
2187			return -EUCLEAN;
2188		}
2189
2190		/*
2191		 * We need to get child blockptr/gen from parent before we can
2192		 * read it.
2193		  */
2194		eb = dst_path->nodes[cur_level + 1];
2195		parent_slot = dst_path->slots[cur_level + 1];
2196		child_gen = btrfs_node_ptr_generation(eb, parent_slot);
2197
2198		/* This node is old, no need to trace */
2199		if (child_gen < last_snapshot)
2200			goto out;
2201
2202		eb = btrfs_read_node_slot(eb, parent_slot);
2203		if (IS_ERR(eb)) {
2204			ret = PTR_ERR(eb);
2205			goto out;
2206		}
2207
2208		dst_path->nodes[cur_level] = eb;
2209		dst_path->slots[cur_level] = 0;
2210
2211		btrfs_tree_read_lock(eb);
2212		dst_path->locks[cur_level] = BTRFS_READ_LOCK;
2213		need_cleanup = true;
2214	}
2215
2216	/* Now record this tree block and its counter part for qgroups */
2217	ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level,
2218				       root_level, trace_leaf);
2219	if (ret < 0)
2220		goto cleanup;
2221
2222	eb = dst_path->nodes[cur_level];
2223
2224	if (cur_level > 0) {
2225		/* Iterate all child tree blocks */
2226		for (i = 0; i < btrfs_header_nritems(eb); i++) {
2227			/* Skip old tree blocks as they won't be swapped */
2228			if (btrfs_node_ptr_generation(eb, i) < last_snapshot)
2229				continue;
2230			dst_path->slots[cur_level] = i;
2231
2232			/* Recursive call (at most 7 times) */
2233			ret = qgroup_trace_new_subtree_blocks(trans, src_eb,
2234					dst_path, cur_level - 1, root_level,
2235					last_snapshot, trace_leaf);
2236			if (ret < 0)
2237				goto cleanup;
2238		}
2239	}
2240
2241cleanup:
2242	if (need_cleanup) {
2243		/* Clean up */
2244		btrfs_tree_unlock_rw(dst_path->nodes[cur_level],
2245				     dst_path->locks[cur_level]);
2246		free_extent_buffer(dst_path->nodes[cur_level]);
2247		dst_path->nodes[cur_level] = NULL;
2248		dst_path->slots[cur_level] = 0;
2249		dst_path->locks[cur_level] = 0;
2250	}
2251out:
2252	return ret;
2253}
2254
2255static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans,
2256				struct extent_buffer *src_eb,
2257				struct extent_buffer *dst_eb,
2258				u64 last_snapshot, bool trace_leaf)
2259{
2260	struct btrfs_fs_info *fs_info = trans->fs_info;
2261	struct btrfs_path *dst_path = NULL;
2262	int level;
2263	int ret;
2264
2265	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2266		return 0;
2267
2268	/* Wrong parameter order */
2269	if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) {
2270		btrfs_err_rl(fs_info,
2271		"%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__,
2272			     btrfs_header_generation(src_eb),
2273			     btrfs_header_generation(dst_eb));
2274		return -EUCLEAN;
2275	}
2276
2277	if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) {
2278		ret = -EIO;
2279		goto out;
2280	}
2281
2282	level = btrfs_header_level(dst_eb);
2283	dst_path = btrfs_alloc_path();
2284	if (!dst_path) {
2285		ret = -ENOMEM;
2286		goto out;
2287	}
2288	/* For dst_path */
2289	atomic_inc(&dst_eb->refs);
2290	dst_path->nodes[level] = dst_eb;
2291	dst_path->slots[level] = 0;
2292	dst_path->locks[level] = 0;
2293
2294	/* Do the generation aware breadth-first search */
2295	ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level,
2296					      level, last_snapshot, trace_leaf);
2297	if (ret < 0)
2298		goto out;
2299	ret = 0;
2300
2301out:
2302	btrfs_free_path(dst_path);
2303	if (ret < 0)
2304		qgroup_mark_inconsistent(fs_info);
2305	return ret;
2306}
2307
2308int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
 
2309			       struct extent_buffer *root_eb,
2310			       u64 root_gen, int root_level)
2311{
2312	struct btrfs_fs_info *fs_info = trans->fs_info;
2313	int ret = 0;
2314	int level;
2315	u8 drop_subptree_thres;
2316	struct extent_buffer *eb = root_eb;
2317	struct btrfs_path *path = NULL;
2318
2319	BUG_ON(root_level < 0 || root_level >= BTRFS_MAX_LEVEL);
2320	BUG_ON(root_eb == NULL);
2321
2322	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2323		return 0;
2324
2325	spin_lock(&fs_info->qgroup_lock);
2326	drop_subptree_thres = fs_info->qgroup_drop_subtree_thres;
2327	spin_unlock(&fs_info->qgroup_lock);
2328
2329	/*
2330	 * This function only gets called for snapshot drop, if we hit a high
2331	 * node here, it means we are going to change ownership for quite a lot
2332	 * of extents, which will greatly slow down btrfs_commit_transaction().
2333	 *
2334	 * So here if we find a high tree here, we just skip the accounting and
2335	 * mark qgroup inconsistent.
2336	 */
2337	if (root_level >= drop_subptree_thres) {
2338		qgroup_mark_inconsistent(fs_info);
2339		return 0;
2340	}
2341
2342	if (!extent_buffer_uptodate(root_eb)) {
2343		struct btrfs_tree_parent_check check = {
2344			.has_first_key = false,
2345			.transid = root_gen,
2346			.level = root_level
2347		};
2348
2349		ret = btrfs_read_extent_buffer(root_eb, &check);
2350		if (ret)
2351			goto out;
2352	}
2353
2354	if (root_level == 0) {
2355		ret = btrfs_qgroup_trace_leaf_items(trans, root_eb);
2356		goto out;
2357	}
2358
2359	path = btrfs_alloc_path();
2360	if (!path)
2361		return -ENOMEM;
2362
2363	/*
2364	 * Walk down the tree.  Missing extent blocks are filled in as
2365	 * we go. Metadata is accounted every time we read a new
2366	 * extent block.
2367	 *
2368	 * When we reach a leaf, we account for file extent items in it,
2369	 * walk back up the tree (adjusting slot pointers as we go)
2370	 * and restart the search process.
2371	 */
2372	atomic_inc(&root_eb->refs);	/* For path */
2373	path->nodes[root_level] = root_eb;
2374	path->slots[root_level] = 0;
2375	path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
2376walk_down:
2377	level = root_level;
2378	while (level >= 0) {
2379		if (path->nodes[level] == NULL) {
 
2380			int parent_slot;
 
2381			u64 child_bytenr;
2382
2383			/*
2384			 * We need to get child blockptr from parent before we
2385			 * can read it.
2386			  */
2387			eb = path->nodes[level + 1];
2388			parent_slot = path->slots[level + 1];
2389			child_bytenr = btrfs_node_blockptr(eb, parent_slot);
 
 
2390
2391			eb = btrfs_read_node_slot(eb, parent_slot);
 
2392			if (IS_ERR(eb)) {
2393				ret = PTR_ERR(eb);
2394				goto out;
 
 
 
 
2395			}
2396
2397			path->nodes[level] = eb;
2398			path->slots[level] = 0;
2399
2400			btrfs_tree_read_lock(eb);
2401			path->locks[level] = BTRFS_READ_LOCK;
 
2402
2403			ret = btrfs_qgroup_trace_extent(trans, child_bytenr,
2404							fs_info->nodesize);
 
 
2405			if (ret)
2406				goto out;
2407		}
2408
2409		if (level == 0) {
2410			ret = btrfs_qgroup_trace_leaf_items(trans,
2411							    path->nodes[level]);
2412			if (ret)
2413				goto out;
2414
2415			/* Nonzero return here means we completed our search */
2416			ret = adjust_slots_upwards(path, root_level);
2417			if (ret)
2418				break;
2419
2420			/* Restart search with new slots */
2421			goto walk_down;
2422		}
2423
2424		level--;
2425	}
2426
2427	ret = 0;
2428out:
2429	btrfs_free_path(path);
2430
2431	return ret;
2432}
2433
2434#define UPDATE_NEW	0
2435#define UPDATE_OLD	1
2436/*
2437 * Walk all of the roots that points to the bytenr and adjust their refcnts.
2438 */
2439static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
2440				struct ulist *roots, struct ulist *tmp,
2441				struct ulist *qgroups, u64 seq, int update_old)
2442{
2443	struct ulist_node *unode;
2444	struct ulist_iterator uiter;
2445	struct ulist_node *tmp_unode;
2446	struct ulist_iterator tmp_uiter;
2447	struct btrfs_qgroup *qg;
2448	int ret = 0;
2449
2450	if (!roots)
2451		return 0;
2452	ULIST_ITER_INIT(&uiter);
2453	while ((unode = ulist_next(roots, &uiter))) {
2454		qg = find_qgroup_rb(fs_info, unode->val);
2455		if (!qg)
2456			continue;
2457
2458		ulist_reinit(tmp);
2459		ret = ulist_add(qgroups, qg->qgroupid, qgroup_to_aux(qg),
2460				GFP_ATOMIC);
2461		if (ret < 0)
2462			return ret;
2463		ret = ulist_add(tmp, qg->qgroupid, qgroup_to_aux(qg), GFP_ATOMIC);
2464		if (ret < 0)
2465			return ret;
2466		ULIST_ITER_INIT(&tmp_uiter);
2467		while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
2468			struct btrfs_qgroup_list *glist;
2469
2470			qg = unode_aux_to_qgroup(tmp_unode);
2471			if (update_old)
2472				btrfs_qgroup_update_old_refcnt(qg, seq, 1);
2473			else
2474				btrfs_qgroup_update_new_refcnt(qg, seq, 1);
2475			list_for_each_entry(glist, &qg->groups, next_group) {
2476				ret = ulist_add(qgroups, glist->group->qgroupid,
2477						qgroup_to_aux(glist->group),
2478						GFP_ATOMIC);
2479				if (ret < 0)
2480					return ret;
2481				ret = ulist_add(tmp, glist->group->qgroupid,
2482						qgroup_to_aux(glist->group),
2483						GFP_ATOMIC);
2484				if (ret < 0)
2485					return ret;
2486			}
2487		}
2488	}
2489	return 0;
2490}
2491
2492/*
2493 * Update qgroup rfer/excl counters.
2494 * Rfer update is easy, codes can explain themselves.
2495 *
2496 * Excl update is tricky, the update is split into 2 parts.
2497 * Part 1: Possible exclusive <-> sharing detect:
2498 *	|	A	|	!A	|
2499 *  -------------------------------------
2500 *  B	|	*	|	-	|
2501 *  -------------------------------------
2502 *  !B	|	+	|	**	|
2503 *  -------------------------------------
2504 *
2505 * Conditions:
2506 * A:	cur_old_roots < nr_old_roots	(not exclusive before)
2507 * !A:	cur_old_roots == nr_old_roots	(possible exclusive before)
2508 * B:	cur_new_roots < nr_new_roots	(not exclusive now)
2509 * !B:	cur_new_roots == nr_new_roots	(possible exclusive now)
2510 *
2511 * Results:
2512 * +: Possible sharing -> exclusive	-: Possible exclusive -> sharing
2513 * *: Definitely not changed.		**: Possible unchanged.
2514 *
2515 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
2516 *
2517 * To make the logic clear, we first use condition A and B to split
2518 * combination into 4 results.
2519 *
2520 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
2521 * only on variant maybe 0.
2522 *
2523 * Lastly, check result **, since there are 2 variants maybe 0, split them
2524 * again(2x2).
2525 * But this time we don't need to consider other things, the codes and logic
2526 * is easy to understand now.
2527 */
2528static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
2529				  struct ulist *qgroups,
2530				  u64 nr_old_roots,
2531				  u64 nr_new_roots,
2532				  u64 num_bytes, u64 seq)
2533{
2534	struct ulist_node *unode;
2535	struct ulist_iterator uiter;
2536	struct btrfs_qgroup *qg;
2537	u64 cur_new_count, cur_old_count;
2538
2539	ULIST_ITER_INIT(&uiter);
2540	while ((unode = ulist_next(qgroups, &uiter))) {
2541		bool dirty = false;
2542
2543		qg = unode_aux_to_qgroup(unode);
2544		cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
2545		cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
2546
2547		trace_qgroup_update_counters(fs_info, qg, cur_old_count,
2548					     cur_new_count);
2549
2550		/* Rfer update part */
2551		if (cur_old_count == 0 && cur_new_count > 0) {
2552			qg->rfer += num_bytes;
2553			qg->rfer_cmpr += num_bytes;
2554			dirty = true;
2555		}
2556		if (cur_old_count > 0 && cur_new_count == 0) {
2557			qg->rfer -= num_bytes;
2558			qg->rfer_cmpr -= num_bytes;
2559			dirty = true;
2560		}
2561
2562		/* Excl update part */
2563		/* Exclusive/none -> shared case */
2564		if (cur_old_count == nr_old_roots &&
2565		    cur_new_count < nr_new_roots) {
2566			/* Exclusive -> shared */
2567			if (cur_old_count != 0) {
2568				qg->excl -= num_bytes;
2569				qg->excl_cmpr -= num_bytes;
2570				dirty = true;
2571			}
2572		}
2573
2574		/* Shared -> exclusive/none case */
2575		if (cur_old_count < nr_old_roots &&
2576		    cur_new_count == nr_new_roots) {
2577			/* Shared->exclusive */
2578			if (cur_new_count != 0) {
2579				qg->excl += num_bytes;
2580				qg->excl_cmpr += num_bytes;
2581				dirty = true;
2582			}
2583		}
2584
2585		/* Exclusive/none -> exclusive/none case */
2586		if (cur_old_count == nr_old_roots &&
2587		    cur_new_count == nr_new_roots) {
2588			if (cur_old_count == 0) {
2589				/* None -> exclusive/none */
2590
2591				if (cur_new_count != 0) {
2592					/* None -> exclusive */
2593					qg->excl += num_bytes;
2594					qg->excl_cmpr += num_bytes;
2595					dirty = true;
2596				}
2597				/* None -> none, nothing changed */
2598			} else {
2599				/* Exclusive -> exclusive/none */
2600
2601				if (cur_new_count == 0) {
2602					/* Exclusive -> none */
2603					qg->excl -= num_bytes;
2604					qg->excl_cmpr -= num_bytes;
2605					dirty = true;
2606				}
2607				/* Exclusive -> exclusive, nothing changed */
2608			}
2609		}
2610
2611		if (dirty)
2612			qgroup_dirty(fs_info, qg);
2613	}
2614	return 0;
2615}
2616
2617/*
2618 * Check if the @roots potentially is a list of fs tree roots
2619 *
2620 * Return 0 for definitely not a fs/subvol tree roots ulist
2621 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
2622 *          one as well)
2623 */
2624static int maybe_fs_roots(struct ulist *roots)
2625{
2626	struct ulist_node *unode;
2627	struct ulist_iterator uiter;
2628
2629	/* Empty one, still possible for fs roots */
2630	if (!roots || roots->nnodes == 0)
2631		return 1;
2632
2633	ULIST_ITER_INIT(&uiter);
2634	unode = ulist_next(roots, &uiter);
2635	if (!unode)
2636		return 1;
2637
2638	/*
2639	 * If it contains fs tree roots, then it must belong to fs/subvol
2640	 * trees.
2641	 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
2642	 */
2643	return is_fstree(unode->val);
2644}
2645
2646int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
2647				u64 num_bytes, struct ulist *old_roots,
2648				struct ulist *new_roots)
 
 
2649{
2650	struct btrfs_fs_info *fs_info = trans->fs_info;
2651	struct ulist *qgroups = NULL;
2652	struct ulist *tmp = NULL;
2653	u64 seq;
2654	u64 nr_new_roots = 0;
2655	u64 nr_old_roots = 0;
2656	int ret = 0;
2657
2658	/*
2659	 * If quotas get disabled meanwhile, the resources need to be freed and
2660	 * we can't just exit here.
2661	 */
2662	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
2663	    fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)
2664		goto out_free;
2665
2666	if (new_roots) {
2667		if (!maybe_fs_roots(new_roots))
2668			goto out_free;
2669		nr_new_roots = new_roots->nnodes;
2670	}
2671	if (old_roots) {
2672		if (!maybe_fs_roots(old_roots))
2673			goto out_free;
2674		nr_old_roots = old_roots->nnodes;
2675	}
2676
2677	/* Quick exit, either not fs tree roots, or won't affect any qgroup */
2678	if (nr_old_roots == 0 && nr_new_roots == 0)
2679		goto out_free;
2680
2681	BUG_ON(!fs_info->quota_root);
2682
2683	trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr,
2684					num_bytes, nr_old_roots, nr_new_roots);
2685
2686	qgroups = ulist_alloc(GFP_NOFS);
2687	if (!qgroups) {
2688		ret = -ENOMEM;
2689		goto out_free;
2690	}
2691	tmp = ulist_alloc(GFP_NOFS);
2692	if (!tmp) {
2693		ret = -ENOMEM;
2694		goto out_free;
2695	}
2696
2697	mutex_lock(&fs_info->qgroup_rescan_lock);
2698	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2699		if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2700			mutex_unlock(&fs_info->qgroup_rescan_lock);
2701			ret = 0;
2702			goto out_free;
2703		}
2704	}
2705	mutex_unlock(&fs_info->qgroup_rescan_lock);
2706
2707	spin_lock(&fs_info->qgroup_lock);
2708	seq = fs_info->qgroup_seq;
2709
2710	/* Update old refcnts using old_roots */
2711	ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
2712				   UPDATE_OLD);
2713	if (ret < 0)
2714		goto out;
2715
2716	/* Update new refcnts using new_roots */
2717	ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
2718				   UPDATE_NEW);
2719	if (ret < 0)
2720		goto out;
2721
2722	qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
2723			       num_bytes, seq);
2724
2725	/*
2726	 * Bump qgroup_seq to avoid seq overlap
2727	 */
2728	fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
2729out:
2730	spin_unlock(&fs_info->qgroup_lock);
2731out_free:
2732	ulist_free(tmp);
2733	ulist_free(qgroups);
2734	ulist_free(old_roots);
2735	ulist_free(new_roots);
2736	return ret;
2737}
2738
2739int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2740{
2741	struct btrfs_fs_info *fs_info = trans->fs_info;
2742	struct btrfs_qgroup_extent_record *record;
2743	struct btrfs_delayed_ref_root *delayed_refs;
2744	struct ulist *new_roots = NULL;
2745	struct rb_node *node;
2746	u64 num_dirty_extents = 0;
2747	u64 qgroup_to_skip;
2748	int ret = 0;
2749
2750	delayed_refs = &trans->transaction->delayed_refs;
2751	qgroup_to_skip = delayed_refs->qgroup_to_skip;
2752	while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2753		record = rb_entry(node, struct btrfs_qgroup_extent_record,
2754				  node);
2755
2756		num_dirty_extents++;
2757		trace_btrfs_qgroup_account_extents(fs_info, record);
2758
2759		if (!ret && !(fs_info->qgroup_flags &
2760			      BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)) {
2761			struct btrfs_backref_walk_ctx ctx = { 0 };
2762
2763			ctx.bytenr = record->bytenr;
2764			ctx.fs_info = fs_info;
2765
2766			/*
2767			 * Old roots should be searched when inserting qgroup
2768			 * extent record.
2769			 *
2770			 * But for INCONSISTENT (NO_ACCOUNTING) -> rescan case,
2771			 * we may have some record inserted during
2772			 * NO_ACCOUNTING (thus no old_roots populated), but
2773			 * later we start rescan, which clears NO_ACCOUNTING,
2774			 * leaving some inserted records without old_roots
2775			 * populated.
2776			 *
2777			 * Those cases are rare and should not cause too much
2778			 * time spent during commit_transaction().
2779			 */
2780			if (!record->old_roots) {
2781				/* Search commit root to find old_roots */
2782				ret = btrfs_find_all_roots(&ctx, false);
 
 
2783				if (ret < 0)
2784					goto cleanup;
2785				record->old_roots = ctx.roots;
2786				ctx.roots = NULL;
2787			}
2788
2789			/* Free the reserved data space */
2790			btrfs_qgroup_free_refroot(fs_info,
2791					record->data_rsv_refroot,
2792					record->data_rsv,
2793					BTRFS_QGROUP_RSV_DATA);
2794			/*
2795			 * Use BTRFS_SEQ_LAST as time_seq to do special search,
2796			 * which doesn't lock tree or delayed_refs and search
2797			 * current root. It's safe inside commit_transaction().
2798			 */
2799			ctx.trans = trans;
2800			ctx.time_seq = BTRFS_SEQ_LAST;
2801			ret = btrfs_find_all_roots(&ctx, false);
2802			if (ret < 0)
2803				goto cleanup;
2804			new_roots = ctx.roots;
2805			if (qgroup_to_skip) {
2806				ulist_del(new_roots, qgroup_to_skip, 0);
2807				ulist_del(record->old_roots, qgroup_to_skip,
2808					  0);
2809			}
2810			ret = btrfs_qgroup_account_extent(trans, record->bytenr,
2811							  record->num_bytes,
2812							  record->old_roots,
2813							  new_roots);
2814			record->old_roots = NULL;
2815			new_roots = NULL;
2816		}
2817cleanup:
2818		ulist_free(record->old_roots);
2819		ulist_free(new_roots);
2820		new_roots = NULL;
2821		rb_erase(node, &delayed_refs->dirty_extent_root);
2822		kfree(record);
2823
2824	}
2825	trace_qgroup_num_dirty_extents(fs_info, trans->transid,
2826				       num_dirty_extents);
2827	return ret;
2828}
2829
2830/*
2831 * called from commit_transaction. Writes all changed qgroups to disk.
2832 */
2833int btrfs_run_qgroups(struct btrfs_trans_handle *trans)
 
2834{
2835	struct btrfs_fs_info *fs_info = trans->fs_info;
2836	int ret = 0;
2837
2838	if (!fs_info->quota_root)
2839		return ret;
2840
2841	spin_lock(&fs_info->qgroup_lock);
2842	while (!list_empty(&fs_info->dirty_qgroups)) {
2843		struct btrfs_qgroup *qgroup;
2844		qgroup = list_first_entry(&fs_info->dirty_qgroups,
2845					  struct btrfs_qgroup, dirty);
2846		list_del_init(&qgroup->dirty);
2847		spin_unlock(&fs_info->qgroup_lock);
2848		ret = update_qgroup_info_item(trans, qgroup);
2849		if (ret)
2850			qgroup_mark_inconsistent(fs_info);
2851		ret = update_qgroup_limit_item(trans, qgroup);
 
2852		if (ret)
2853			qgroup_mark_inconsistent(fs_info);
 
2854		spin_lock(&fs_info->qgroup_lock);
2855	}
2856	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2857		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
2858	else
2859		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
2860	spin_unlock(&fs_info->qgroup_lock);
2861
2862	ret = update_qgroup_status_item(trans);
2863	if (ret)
2864		qgroup_mark_inconsistent(fs_info);
2865
2866	return ret;
2867}
2868
2869/*
2870 * Copy the accounting information between qgroups. This is necessary
2871 * when a snapshot or a subvolume is created. Throwing an error will
2872 * cause a transaction abort so we take extra care here to only error
2873 * when a readonly fs is a reasonable outcome.
2874 */
2875int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
2876			 u64 objectid, struct btrfs_qgroup_inherit *inherit)
 
2877{
2878	int ret = 0;
2879	int i;
2880	u64 *i_qgroups;
2881	bool committing = false;
2882	struct btrfs_fs_info *fs_info = trans->fs_info;
2883	struct btrfs_root *quota_root;
2884	struct btrfs_qgroup *srcgroup;
2885	struct btrfs_qgroup *dstgroup;
2886	bool need_rescan = false;
2887	u32 level_size = 0;
2888	u64 nums;
2889
2890	/*
2891	 * There are only two callers of this function.
2892	 *
2893	 * One in create_subvol() in the ioctl context, which needs to hold
2894	 * the qgroup_ioctl_lock.
2895	 *
2896	 * The other one in create_pending_snapshot() where no other qgroup
2897	 * code can modify the fs as they all need to either start a new trans
2898	 * or hold a trans handler, thus we don't need to hold
2899	 * qgroup_ioctl_lock.
2900	 * This would avoid long and complex lock chain and make lockdep happy.
2901	 */
2902	spin_lock(&fs_info->trans_lock);
2903	if (trans->transaction->state == TRANS_STATE_COMMIT_DOING)
2904		committing = true;
2905	spin_unlock(&fs_info->trans_lock);
2906
2907	if (!committing)
2908		mutex_lock(&fs_info->qgroup_ioctl_lock);
2909	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2910		goto out;
2911
2912	quota_root = fs_info->quota_root;
2913	if (!quota_root) {
2914		ret = -EINVAL;
2915		goto out;
2916	}
2917
2918	if (inherit) {
2919		i_qgroups = (u64 *)(inherit + 1);
2920		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
2921		       2 * inherit->num_excl_copies;
2922		for (i = 0; i < nums; ++i) {
2923			srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
2924
2925			/*
2926			 * Zero out invalid groups so we can ignore
2927			 * them later.
2928			 */
2929			if (!srcgroup ||
2930			    ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
2931				*i_qgroups = 0ULL;
2932
2933			++i_qgroups;
2934		}
2935	}
2936
2937	/*
2938	 * create a tracking group for the subvol itself
2939	 */
2940	ret = add_qgroup_item(trans, quota_root, objectid);
2941	if (ret)
2942		goto out;
2943
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2944	/*
2945	 * add qgroup to all inherited groups
2946	 */
2947	if (inherit) {
2948		i_qgroups = (u64 *)(inherit + 1);
2949		for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
2950			if (*i_qgroups == 0)
2951				continue;
2952			ret = add_qgroup_relation_item(trans, objectid,
2953						       *i_qgroups);
2954			if (ret && ret != -EEXIST)
2955				goto out;
2956			ret = add_qgroup_relation_item(trans, *i_qgroups,
2957						       objectid);
2958			if (ret && ret != -EEXIST)
2959				goto out;
2960		}
2961		ret = 0;
2962	}
2963
2964
2965	spin_lock(&fs_info->qgroup_lock);
2966
2967	dstgroup = add_qgroup_rb(fs_info, objectid);
2968	if (IS_ERR(dstgroup)) {
2969		ret = PTR_ERR(dstgroup);
2970		goto unlock;
2971	}
2972
2973	if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
2974		dstgroup->lim_flags = inherit->lim.flags;
2975		dstgroup->max_rfer = inherit->lim.max_rfer;
2976		dstgroup->max_excl = inherit->lim.max_excl;
2977		dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
2978		dstgroup->rsv_excl = inherit->lim.rsv_excl;
2979
2980		qgroup_dirty(fs_info, dstgroup);
 
 
 
 
 
 
 
2981	}
2982
2983	if (srcid) {
2984		srcgroup = find_qgroup_rb(fs_info, srcid);
2985		if (!srcgroup)
2986			goto unlock;
2987
2988		/*
2989		 * We call inherit after we clone the root in order to make sure
2990		 * our counts don't go crazy, so at this point the only
2991		 * difference between the two roots should be the root node.
2992		 */
2993		level_size = fs_info->nodesize;
2994		dstgroup->rfer = srcgroup->rfer;
2995		dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
2996		dstgroup->excl = level_size;
2997		dstgroup->excl_cmpr = level_size;
2998		srcgroup->excl = level_size;
2999		srcgroup->excl_cmpr = level_size;
3000
3001		/* inherit the limit info */
3002		dstgroup->lim_flags = srcgroup->lim_flags;
3003		dstgroup->max_rfer = srcgroup->max_rfer;
3004		dstgroup->max_excl = srcgroup->max_excl;
3005		dstgroup->rsv_rfer = srcgroup->rsv_rfer;
3006		dstgroup->rsv_excl = srcgroup->rsv_excl;
3007
3008		qgroup_dirty(fs_info, dstgroup);
3009		qgroup_dirty(fs_info, srcgroup);
3010	}
3011
3012	if (!inherit)
3013		goto unlock;
3014
3015	i_qgroups = (u64 *)(inherit + 1);
3016	for (i = 0; i < inherit->num_qgroups; ++i) {
3017		if (*i_qgroups) {
3018			ret = add_relation_rb(fs_info, objectid, *i_qgroups);
3019			if (ret)
3020				goto unlock;
3021		}
3022		++i_qgroups;
3023
3024		/*
3025		 * If we're doing a snapshot, and adding the snapshot to a new
3026		 * qgroup, the numbers are guaranteed to be incorrect.
3027		 */
3028		if (srcid)
3029			need_rescan = true;
3030	}
3031
3032	for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
3033		struct btrfs_qgroup *src;
3034		struct btrfs_qgroup *dst;
3035
3036		if (!i_qgroups[0] || !i_qgroups[1])
3037			continue;
3038
3039		src = find_qgroup_rb(fs_info, i_qgroups[0]);
3040		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3041
3042		if (!src || !dst) {
3043			ret = -EINVAL;
3044			goto unlock;
3045		}
3046
3047		dst->rfer = src->rfer - level_size;
3048		dst->rfer_cmpr = src->rfer_cmpr - level_size;
3049
3050		/* Manually tweaking numbers certainly needs a rescan */
3051		need_rescan = true;
3052	}
3053	for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
3054		struct btrfs_qgroup *src;
3055		struct btrfs_qgroup *dst;
3056
3057		if (!i_qgroups[0] || !i_qgroups[1])
3058			continue;
3059
3060		src = find_qgroup_rb(fs_info, i_qgroups[0]);
3061		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
3062
3063		if (!src || !dst) {
3064			ret = -EINVAL;
3065			goto unlock;
3066		}
3067
3068		dst->excl = src->excl + level_size;
3069		dst->excl_cmpr = src->excl_cmpr + level_size;
3070		need_rescan = true;
3071	}
3072
3073unlock:
3074	spin_unlock(&fs_info->qgroup_lock);
3075	if (!ret)
3076		ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup);
3077out:
3078	if (!committing)
3079		mutex_unlock(&fs_info->qgroup_ioctl_lock);
3080	if (need_rescan)
3081		qgroup_mark_inconsistent(fs_info);
3082	return ret;
3083}
3084
3085static bool qgroup_check_limits(const struct btrfs_qgroup *qg, u64 num_bytes)
 
 
 
 
 
 
 
 
 
 
3086{
 
 
 
3087	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
3088	    qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
3089		return false;
3090
3091	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
3092	    qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
3093		return false;
3094
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3095	return true;
3096}
3097
3098static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
3099			  enum btrfs_qgroup_rsv_type type)
3100{
 
3101	struct btrfs_qgroup *qgroup;
3102	struct btrfs_fs_info *fs_info = root->fs_info;
3103	u64 ref_root = root->root_key.objectid;
3104	int ret = 0;
3105	struct ulist_node *unode;
3106	struct ulist_iterator uiter;
3107
3108	if (!is_fstree(ref_root))
3109		return 0;
3110
3111	if (num_bytes == 0)
3112		return 0;
3113
3114	if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
3115	    capable(CAP_SYS_RESOURCE))
3116		enforce = false;
3117
3118	spin_lock(&fs_info->qgroup_lock);
3119	if (!fs_info->quota_root)
 
3120		goto out;
3121
3122	qgroup = find_qgroup_rb(fs_info, ref_root);
3123	if (!qgroup)
3124		goto out;
3125
3126	/*
3127	 * in a first step, we check all affected qgroups if any limits would
3128	 * be exceeded
3129	 */
3130	ulist_reinit(fs_info->qgroup_ulist);
3131	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3132			qgroup_to_aux(qgroup), GFP_ATOMIC);
3133	if (ret < 0)
3134		goto out;
3135	ULIST_ITER_INIT(&uiter);
3136	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3137		struct btrfs_qgroup *qg;
3138		struct btrfs_qgroup_list *glist;
3139
3140		qg = unode_aux_to_qgroup(unode);
3141
3142		if (enforce && !qgroup_check_limits(qg, num_bytes)) {
3143			ret = -EDQUOT;
3144			goto out;
3145		}
3146
3147		list_for_each_entry(glist, &qg->groups, next_group) {
3148			ret = ulist_add(fs_info->qgroup_ulist,
3149					glist->group->qgroupid,
3150					qgroup_to_aux(glist->group), GFP_ATOMIC);
3151			if (ret < 0)
3152				goto out;
3153		}
3154	}
3155	ret = 0;
3156	/*
3157	 * no limits exceeded, now record the reservation into all qgroups
3158	 */
3159	ULIST_ITER_INIT(&uiter);
3160	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3161		struct btrfs_qgroup *qg;
3162
3163		qg = unode_aux_to_qgroup(unode);
3164
 
3165		qgroup_rsv_add(fs_info, qg, num_bytes, type);
3166	}
3167
3168out:
3169	spin_unlock(&fs_info->qgroup_lock);
3170	return ret;
3171}
3172
3173/*
3174 * Free @num_bytes of reserved space with @type for qgroup.  (Normally level 0
3175 * qgroup).
3176 *
3177 * Will handle all higher level qgroup too.
3178 *
3179 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
3180 * This special case is only used for META_PERTRANS type.
3181 */
3182void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
3183			       u64 ref_root, u64 num_bytes,
3184			       enum btrfs_qgroup_rsv_type type)
3185{
 
3186	struct btrfs_qgroup *qgroup;
3187	struct ulist_node *unode;
3188	struct ulist_iterator uiter;
3189	int ret = 0;
3190
3191	if (!is_fstree(ref_root))
3192		return;
3193
3194	if (num_bytes == 0)
3195		return;
3196
3197	if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
3198		WARN(1, "%s: Invalid type to free", __func__);
3199		return;
3200	}
3201	spin_lock(&fs_info->qgroup_lock);
3202
3203	if (!fs_info->quota_root)
 
3204		goto out;
3205
3206	qgroup = find_qgroup_rb(fs_info, ref_root);
3207	if (!qgroup)
3208		goto out;
3209
3210	if (num_bytes == (u64)-1)
3211		/*
3212		 * We're freeing all pertrans rsv, get reserved value from
3213		 * level 0 qgroup as real num_bytes to free.
3214		 */
3215		num_bytes = qgroup->rsv.values[type];
3216
3217	ulist_reinit(fs_info->qgroup_ulist);
3218	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3219			qgroup_to_aux(qgroup), GFP_ATOMIC);
3220	if (ret < 0)
3221		goto out;
3222	ULIST_ITER_INIT(&uiter);
3223	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3224		struct btrfs_qgroup *qg;
3225		struct btrfs_qgroup_list *glist;
3226
3227		qg = unode_aux_to_qgroup(unode);
3228
 
3229		qgroup_rsv_release(fs_info, qg, num_bytes, type);
3230
3231		list_for_each_entry(glist, &qg->groups, next_group) {
3232			ret = ulist_add(fs_info->qgroup_ulist,
3233					glist->group->qgroupid,
3234					qgroup_to_aux(glist->group), GFP_ATOMIC);
3235			if (ret < 0)
3236				goto out;
3237		}
3238	}
3239
3240out:
3241	spin_unlock(&fs_info->qgroup_lock);
3242}
3243
3244/*
3245 * Check if the leaf is the last leaf. Which means all node pointers
3246 * are at their last position.
3247 */
3248static bool is_last_leaf(struct btrfs_path *path)
3249{
3250	int i;
3251
3252	for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
3253		if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1)
3254			return false;
3255	}
3256	return true;
3257}
3258
3259/*
3260 * returns < 0 on error, 0 when more leafs are to be scanned.
3261 * returns 1 when done.
3262 */
3263static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans,
3264			      struct btrfs_path *path)
 
3265{
3266	struct btrfs_fs_info *fs_info = trans->fs_info;
3267	struct btrfs_root *extent_root;
3268	struct btrfs_key found;
3269	struct extent_buffer *scratch_leaf = NULL;
 
 
3270	u64 num_bytes;
3271	bool done;
3272	int slot;
3273	int ret;
3274
3275	mutex_lock(&fs_info->qgroup_rescan_lock);
3276	extent_root = btrfs_extent_root(fs_info,
3277				fs_info->qgroup_rescan_progress.objectid);
3278	ret = btrfs_search_slot_for_read(extent_root,
3279					 &fs_info->qgroup_rescan_progress,
3280					 path, 1, 0);
3281
3282	btrfs_debug(fs_info,
3283		"current progress key (%llu %u %llu), search_slot ret %d",
3284		fs_info->qgroup_rescan_progress.objectid,
3285		fs_info->qgroup_rescan_progress.type,
3286		fs_info->qgroup_rescan_progress.offset, ret);
3287
3288	if (ret) {
3289		/*
3290		 * The rescan is about to end, we will not be scanning any
3291		 * further blocks. We cannot unset the RESCAN flag here, because
3292		 * we want to commit the transaction if everything went well.
3293		 * To make the live accounting work in this phase, we set our
3294		 * scan progress pointer such that every real extent objectid
3295		 * will be smaller.
3296		 */
3297		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3298		btrfs_release_path(path);
3299		mutex_unlock(&fs_info->qgroup_rescan_lock);
3300		return ret;
3301	}
3302	done = is_last_leaf(path);
3303
3304	btrfs_item_key_to_cpu(path->nodes[0], &found,
3305			      btrfs_header_nritems(path->nodes[0]) - 1);
3306	fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
3307
 
3308	scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
3309	if (!scratch_leaf) {
3310		ret = -ENOMEM;
3311		mutex_unlock(&fs_info->qgroup_rescan_lock);
3312		goto out;
3313	}
 
 
 
3314	slot = path->slots[0];
3315	btrfs_release_path(path);
3316	mutex_unlock(&fs_info->qgroup_rescan_lock);
3317
3318	for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
3319		struct btrfs_backref_walk_ctx ctx = { 0 };
3320
3321		btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
3322		if (found.type != BTRFS_EXTENT_ITEM_KEY &&
3323		    found.type != BTRFS_METADATA_ITEM_KEY)
3324			continue;
3325		if (found.type == BTRFS_METADATA_ITEM_KEY)
3326			num_bytes = fs_info->nodesize;
3327		else
3328			num_bytes = found.offset;
3329
3330		ctx.bytenr = found.objectid;
3331		ctx.fs_info = fs_info;
3332
3333		ret = btrfs_find_all_roots(&ctx, false);
3334		if (ret < 0)
3335			goto out;
3336		/* For rescan, just pass old_roots as NULL */
3337		ret = btrfs_qgroup_account_extent(trans, found.objectid,
3338						  num_bytes, NULL, ctx.roots);
3339		if (ret < 0)
3340			goto out;
3341	}
3342out:
3343	if (scratch_leaf)
 
3344		free_extent_buffer(scratch_leaf);
3345
3346	if (done && !ret) {
3347		ret = 1;
3348		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
3349	}
3350	return ret;
3351}
3352
3353static bool rescan_should_stop(struct btrfs_fs_info *fs_info)
3354{
3355	return btrfs_fs_closing(fs_info) ||
3356		test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state) ||
3357		!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3358			  fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN;
3359}
3360
3361static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
3362{
3363	struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
3364						     qgroup_rescan_work);
3365	struct btrfs_path *path;
3366	struct btrfs_trans_handle *trans = NULL;
3367	int err = -ENOMEM;
3368	int ret = 0;
3369	bool stopped = false;
3370	bool did_leaf_rescans = false;
3371
3372	path = btrfs_alloc_path();
3373	if (!path)
3374		goto out;
3375	/*
3376	 * Rescan should only search for commit root, and any later difference
3377	 * should be recorded by qgroup
3378	 */
3379	path->search_commit_root = 1;
3380	path->skip_locking = 1;
3381
3382	err = 0;
3383	while (!err && !(stopped = rescan_should_stop(fs_info))) {
3384		trans = btrfs_start_transaction(fs_info->fs_root, 0);
3385		if (IS_ERR(trans)) {
3386			err = PTR_ERR(trans);
3387			break;
3388		}
3389
3390		err = qgroup_rescan_leaf(trans, path);
3391		did_leaf_rescans = true;
3392
 
3393		if (err > 0)
3394			btrfs_commit_transaction(trans);
3395		else
3396			btrfs_end_transaction(trans);
3397	}
3398
3399out:
3400	btrfs_free_path(path);
3401
3402	mutex_lock(&fs_info->qgroup_rescan_lock);
 
 
 
3403	if (err > 0 &&
3404	    fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
3405		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3406	} else if (err < 0 || stopped) {
3407		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
3408	}
3409	mutex_unlock(&fs_info->qgroup_rescan_lock);
3410
3411	/*
3412	 * Only update status, since the previous part has already updated the
3413	 * qgroup info, and only if we did any actual work. This also prevents
3414	 * race with a concurrent quota disable, which has already set
3415	 * fs_info->quota_root to NULL and cleared BTRFS_FS_QUOTA_ENABLED at
3416	 * btrfs_quota_disable().
3417	 */
3418	if (did_leaf_rescans) {
3419		trans = btrfs_start_transaction(fs_info->quota_root, 1);
3420		if (IS_ERR(trans)) {
3421			err = PTR_ERR(trans);
3422			trans = NULL;
3423			btrfs_err(fs_info,
3424				  "fail to start transaction for status update: %d",
3425				  err);
3426		}
3427	} else {
3428		trans = NULL;
3429	}
3430
3431	mutex_lock(&fs_info->qgroup_rescan_lock);
3432	if (!stopped ||
3433	    fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN)
3434		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3435	if (trans) {
3436		ret = update_qgroup_status_item(trans);
3437		if (ret < 0) {
3438			err = ret;
3439			btrfs_err(fs_info, "fail to update qgroup status: %d",
3440				  err);
3441		}
3442	}
3443	fs_info->qgroup_rescan_running = false;
3444	fs_info->qgroup_flags &= ~BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN;
3445	complete_all(&fs_info->qgroup_rescan_completion);
3446	mutex_unlock(&fs_info->qgroup_rescan_lock);
3447
3448	if (!trans)
3449		return;
3450
3451	btrfs_end_transaction(trans);
3452
3453	if (stopped) {
3454		btrfs_info(fs_info, "qgroup scan paused");
3455	} else if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) {
3456		btrfs_info(fs_info, "qgroup scan cancelled");
3457	} else if (err >= 0) {
3458		btrfs_info(fs_info, "qgroup scan completed%s",
3459			err > 0 ? " (inconsistency flag cleared)" : "");
3460	} else {
3461		btrfs_err(fs_info, "qgroup scan failed with %d", err);
3462	}
 
 
 
 
 
 
3463}
3464
3465/*
3466 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
3467 * memory required for the rescan context.
3468 */
3469static int
3470qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
3471		   int init_flags)
3472{
3473	int ret = 0;
3474
3475	if (!init_flags) {
3476		/* we're resuming qgroup rescan at mount time */
3477		if (!(fs_info->qgroup_flags &
3478		      BTRFS_QGROUP_STATUS_FLAG_RESCAN)) {
3479			btrfs_warn(fs_info,
3480			"qgroup rescan init failed, qgroup rescan is not queued");
3481			ret = -EINVAL;
3482		} else if (!(fs_info->qgroup_flags &
3483			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3484			btrfs_warn(fs_info,
3485			"qgroup rescan init failed, qgroup is not enabled");
3486			ret = -EINVAL;
3487		}
3488
3489		if (ret)
3490			return ret;
3491	}
3492
3493	mutex_lock(&fs_info->qgroup_rescan_lock);
 
3494
3495	if (init_flags) {
3496		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3497			btrfs_warn(fs_info,
3498				   "qgroup rescan is already in progress");
3499			ret = -EINPROGRESS;
3500		} else if (!(fs_info->qgroup_flags &
3501			     BTRFS_QGROUP_STATUS_FLAG_ON)) {
3502			btrfs_warn(fs_info,
3503			"qgroup rescan init failed, qgroup is not enabled");
3504			ret = -EINVAL;
3505		} else if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
3506			/* Quota disable is in progress */
3507			ret = -EBUSY;
3508		}
3509
3510		if (ret) {
 
3511			mutex_unlock(&fs_info->qgroup_rescan_lock);
3512			return ret;
3513		}
3514		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3515	}
3516
3517	memset(&fs_info->qgroup_rescan_progress, 0,
3518		sizeof(fs_info->qgroup_rescan_progress));
3519	fs_info->qgroup_flags &= ~(BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN |
3520				   BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING);
3521	fs_info->qgroup_rescan_progress.objectid = progress_objectid;
3522	init_completion(&fs_info->qgroup_rescan_completion);
 
 
 
3523	mutex_unlock(&fs_info->qgroup_rescan_lock);
3524
 
 
3525	btrfs_init_work(&fs_info->qgroup_rescan_work,
 
3526			btrfs_qgroup_rescan_worker, NULL, NULL);
 
 
 
 
 
 
 
3527	return 0;
3528}
3529
3530static void
3531qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
3532{
3533	struct rb_node *n;
3534	struct btrfs_qgroup *qgroup;
3535
3536	spin_lock(&fs_info->qgroup_lock);
3537	/* clear all current qgroup tracking information */
3538	for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
3539		qgroup = rb_entry(n, struct btrfs_qgroup, node);
3540		qgroup->rfer = 0;
3541		qgroup->rfer_cmpr = 0;
3542		qgroup->excl = 0;
3543		qgroup->excl_cmpr = 0;
3544		qgroup_dirty(fs_info, qgroup);
3545	}
3546	spin_unlock(&fs_info->qgroup_lock);
3547}
3548
3549int
3550btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
3551{
3552	int ret = 0;
3553	struct btrfs_trans_handle *trans;
3554
3555	ret = qgroup_rescan_init(fs_info, 0, 1);
3556	if (ret)
3557		return ret;
3558
3559	/*
3560	 * We have set the rescan_progress to 0, which means no more
3561	 * delayed refs will be accounted by btrfs_qgroup_account_ref.
3562	 * However, btrfs_qgroup_account_ref may be right after its call
3563	 * to btrfs_find_all_roots, in which case it would still do the
3564	 * accounting.
3565	 * To solve this, we're committing the transaction, which will
3566	 * ensure we run all delayed refs and only after that, we are
3567	 * going to clear all tracking information for a clean start.
3568	 */
3569
3570	trans = btrfs_join_transaction(fs_info->fs_root);
3571	if (IS_ERR(trans)) {
3572		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3573		return PTR_ERR(trans);
3574	}
3575	ret = btrfs_commit_transaction(trans);
3576	if (ret) {
3577		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
3578		return ret;
3579	}
3580
3581	qgroup_rescan_zero_tracking(fs_info);
3582
3583	mutex_lock(&fs_info->qgroup_rescan_lock);
3584	fs_info->qgroup_rescan_running = true;
3585	btrfs_queue_work(fs_info->qgroup_rescan_workers,
3586			 &fs_info->qgroup_rescan_work);
3587	mutex_unlock(&fs_info->qgroup_rescan_lock);
3588
3589	return 0;
3590}
3591
3592int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
3593				     bool interruptible)
3594{
3595	int running;
3596	int ret = 0;
3597
3598	mutex_lock(&fs_info->qgroup_rescan_lock);
 
3599	running = fs_info->qgroup_rescan_running;
 
3600	mutex_unlock(&fs_info->qgroup_rescan_lock);
3601
3602	if (!running)
3603		return 0;
3604
3605	if (interruptible)
3606		ret = wait_for_completion_interruptible(
3607					&fs_info->qgroup_rescan_completion);
3608	else
3609		wait_for_completion(&fs_info->qgroup_rescan_completion);
3610
3611	return ret;
3612}
3613
3614/*
3615 * this is only called from open_ctree where we're still single threaded, thus
3616 * locking is omitted here.
3617 */
3618void
3619btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
3620{
3621	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3622		mutex_lock(&fs_info->qgroup_rescan_lock);
3623		fs_info->qgroup_rescan_running = true;
3624		btrfs_queue_work(fs_info->qgroup_rescan_workers,
3625				 &fs_info->qgroup_rescan_work);
3626		mutex_unlock(&fs_info->qgroup_rescan_lock);
3627	}
3628}
3629
3630#define rbtree_iterate_from_safe(node, next, start)				\
3631       for (node = start; node && ({ next = rb_next(node); 1;}); node = next)
3632
3633static int qgroup_unreserve_range(struct btrfs_inode *inode,
3634				  struct extent_changeset *reserved, u64 start,
3635				  u64 len)
3636{
3637	struct rb_node *node;
3638	struct rb_node *next;
3639	struct ulist_node *entry;
3640	int ret = 0;
3641
3642	node = reserved->range_changed.root.rb_node;
3643	if (!node)
3644		return 0;
3645	while (node) {
3646		entry = rb_entry(node, struct ulist_node, rb_node);
3647		if (entry->val < start)
3648			node = node->rb_right;
3649		else
3650			node = node->rb_left;
3651	}
3652
3653	if (entry->val > start && rb_prev(&entry->rb_node))
3654		entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node,
3655				 rb_node);
3656
3657	rbtree_iterate_from_safe(node, next, &entry->rb_node) {
3658		u64 entry_start;
3659		u64 entry_end;
3660		u64 entry_len;
3661		int clear_ret;
3662
3663		entry = rb_entry(node, struct ulist_node, rb_node);
3664		entry_start = entry->val;
3665		entry_end = entry->aux;
3666		entry_len = entry_end - entry_start + 1;
3667
3668		if (entry_start >= start + len)
3669			break;
3670		if (entry_start + entry_len <= start)
3671			continue;
3672		/*
3673		 * Now the entry is in [start, start + len), revert the
3674		 * EXTENT_QGROUP_RESERVED bit.
3675		 */
3676		clear_ret = clear_extent_bits(&inode->io_tree, entry_start,
3677					      entry_end, EXTENT_QGROUP_RESERVED);
3678		if (!ret && clear_ret < 0)
3679			ret = clear_ret;
3680
3681		ulist_del(&reserved->range_changed, entry->val, entry->aux);
3682		if (likely(reserved->bytes_changed >= entry_len)) {
3683			reserved->bytes_changed -= entry_len;
3684		} else {
3685			WARN_ON(1);
3686			reserved->bytes_changed = 0;
3687		}
3688	}
3689
3690	return ret;
3691}
3692
3693/*
3694 * Try to free some space for qgroup.
3695 *
3696 * For qgroup, there are only 3 ways to free qgroup space:
3697 * - Flush nodatacow write
3698 *   Any nodatacow write will free its reserved data space at run_delalloc_range().
3699 *   In theory, we should only flush nodatacow inodes, but it's not yet
3700 *   possible, so we need to flush the whole root.
3701 *
3702 * - Wait for ordered extents
3703 *   When ordered extents are finished, their reserved metadata is finally
3704 *   converted to per_trans status, which can be freed by later commit
3705 *   transaction.
3706 *
3707 * - Commit transaction
3708 *   This would free the meta_per_trans space.
3709 *   In theory this shouldn't provide much space, but any more qgroup space
3710 *   is needed.
3711 */
3712static int try_flush_qgroup(struct btrfs_root *root)
3713{
3714	struct btrfs_trans_handle *trans;
3715	int ret;
3716
3717	/* Can't hold an open transaction or we run the risk of deadlocking. */
3718	ASSERT(current->journal_info == NULL);
3719	if (WARN_ON(current->journal_info))
3720		return 0;
3721
3722	/*
3723	 * We don't want to run flush again and again, so if there is a running
3724	 * one, we won't try to start a new flush, but exit directly.
3725	 */
3726	if (test_and_set_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)) {
3727		wait_event(root->qgroup_flush_wait,
3728			!test_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state));
3729		return 0;
3730	}
3731
3732	ret = btrfs_start_delalloc_snapshot(root, true);
3733	if (ret < 0)
3734		goto out;
3735	btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
3736
3737	trans = btrfs_join_transaction(root);
3738	if (IS_ERR(trans)) {
3739		ret = PTR_ERR(trans);
3740		goto out;
3741	}
3742
3743	ret = btrfs_commit_transaction(trans);
3744out:
3745	clear_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state);
3746	wake_up(&root->qgroup_flush_wait);
3747	return ret;
3748}
3749
3750static int qgroup_reserve_data(struct btrfs_inode *inode,
3751			struct extent_changeset **reserved_ret, u64 start,
3752			u64 len)
3753{
3754	struct btrfs_root *root = inode->root;
 
 
3755	struct extent_changeset *reserved;
3756	bool new_reserved = false;
3757	u64 orig_reserved;
3758	u64 to_reserve;
3759	int ret;
3760
3761	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags) ||
3762	    !is_fstree(root->root_key.objectid) || len == 0)
3763		return 0;
3764
3765	/* @reserved parameter is mandatory for qgroup */
3766	if (WARN_ON(!reserved_ret))
3767		return -EINVAL;
3768	if (!*reserved_ret) {
3769		new_reserved = true;
3770		*reserved_ret = extent_changeset_alloc();
3771		if (!*reserved_ret)
3772			return -ENOMEM;
3773	}
3774	reserved = *reserved_ret;
3775	/* Record already reserved space */
3776	orig_reserved = reserved->bytes_changed;
3777	ret = set_record_extent_bits(&inode->io_tree, start,
3778			start + len -1, EXTENT_QGROUP_RESERVED, reserved);
3779
3780	/* Newly reserved space */
3781	to_reserve = reserved->bytes_changed - orig_reserved;
3782	trace_btrfs_qgroup_reserve_data(&inode->vfs_inode, start, len,
3783					to_reserve, QGROUP_RESERVE);
3784	if (ret < 0)
3785		goto out;
3786	ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
3787	if (ret < 0)
3788		goto cleanup;
3789
3790	return ret;
3791
3792cleanup:
3793	qgroup_unreserve_range(inode, reserved, start, len);
3794out:
3795	if (new_reserved) {
3796		extent_changeset_free(reserved);
3797		*reserved_ret = NULL;
3798	}
3799	return ret;
3800}
3801
3802/*
3803 * Reserve qgroup space for range [start, start + len).
3804 *
3805 * This function will either reserve space from related qgroups or do nothing
3806 * if the range is already reserved.
3807 *
3808 * Return 0 for successful reservation
3809 * Return <0 for error (including -EQUOT)
3810 *
3811 * NOTE: This function may sleep for memory allocation, dirty page flushing and
3812 *	 commit transaction. So caller should not hold any dirty page locked.
3813 */
3814int btrfs_qgroup_reserve_data(struct btrfs_inode *inode,
3815			struct extent_changeset **reserved_ret, u64 start,
3816			u64 len)
3817{
3818	int ret;
3819
3820	ret = qgroup_reserve_data(inode, reserved_ret, start, len);
3821	if (ret <= 0 && ret != -EDQUOT)
3822		return ret;
3823
3824	ret = try_flush_qgroup(inode->root);
3825	if (ret < 0)
3826		return ret;
3827	return qgroup_reserve_data(inode, reserved_ret, start, len);
3828}
3829
3830/* Free ranges specified by @reserved, normally in error path */
3831static int qgroup_free_reserved_data(struct btrfs_inode *inode,
3832			struct extent_changeset *reserved, u64 start, u64 len)
3833{
3834	struct btrfs_root *root = inode->root;
3835	struct ulist_node *unode;
3836	struct ulist_iterator uiter;
3837	struct extent_changeset changeset;
3838	int freed = 0;
3839	int ret;
3840
3841	extent_changeset_init(&changeset);
3842	len = round_up(start + len, root->fs_info->sectorsize);
3843	start = round_down(start, root->fs_info->sectorsize);
3844
3845	ULIST_ITER_INIT(&uiter);
3846	while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
3847		u64 range_start = unode->val;
3848		/* unode->aux is the inclusive end */
3849		u64 range_len = unode->aux - range_start + 1;
3850		u64 free_start;
3851		u64 free_len;
3852
3853		extent_changeset_release(&changeset);
3854
3855		/* Only free range in range [start, start + len) */
3856		if (range_start >= start + len ||
3857		    range_start + range_len <= start)
3858			continue;
3859		free_start = max(range_start, start);
3860		free_len = min(start + len, range_start + range_len) -
3861			   free_start;
3862		/*
3863		 * TODO: To also modify reserved->ranges_reserved to reflect
3864		 * the modification.
3865		 *
3866		 * However as long as we free qgroup reserved according to
3867		 * EXTENT_QGROUP_RESERVED, we won't double free.
3868		 * So not need to rush.
3869		 */
3870		ret = clear_record_extent_bits(&inode->io_tree, free_start,
3871				free_start + free_len - 1,
3872				EXTENT_QGROUP_RESERVED, &changeset);
3873		if (ret < 0)
3874			goto out;
3875		freed += changeset.bytes_changed;
3876	}
3877	btrfs_qgroup_free_refroot(root->fs_info, root->root_key.objectid, freed,
3878				  BTRFS_QGROUP_RSV_DATA);
3879	ret = freed;
3880out:
3881	extent_changeset_release(&changeset);
3882	return ret;
3883}
3884
3885static int __btrfs_qgroup_release_data(struct btrfs_inode *inode,
3886			struct extent_changeset *reserved, u64 start, u64 len,
3887			int free)
3888{
3889	struct extent_changeset changeset;
3890	int trace_op = QGROUP_RELEASE;
3891	int ret;
3892
3893	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &inode->root->fs_info->flags))
3894		return 0;
3895
3896	/* In release case, we shouldn't have @reserved */
3897	WARN_ON(!free && reserved);
3898	if (free && reserved)
3899		return qgroup_free_reserved_data(inode, reserved, start, len);
3900	extent_changeset_init(&changeset);
3901	ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1,
3902				       EXTENT_QGROUP_RESERVED, &changeset);
3903	if (ret < 0)
3904		goto out;
3905
3906	if (free)
3907		trace_op = QGROUP_FREE;
3908	trace_btrfs_qgroup_release_data(&inode->vfs_inode, start, len,
3909					changeset.bytes_changed, trace_op);
3910	if (free)
3911		btrfs_qgroup_free_refroot(inode->root->fs_info,
3912				inode->root->root_key.objectid,
3913				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3914	ret = changeset.bytes_changed;
3915out:
3916	extent_changeset_release(&changeset);
3917	return ret;
3918}
3919
3920/*
3921 * Free a reserved space range from io_tree and related qgroups
3922 *
3923 * Should be called when a range of pages get invalidated before reaching disk.
3924 * Or for error cleanup case.
3925 * if @reserved is given, only reserved range in [@start, @start + @len) will
3926 * be freed.
3927 *
3928 * For data written to disk, use btrfs_qgroup_release_data().
3929 *
3930 * NOTE: This function may sleep for memory allocation.
3931 */
3932int btrfs_qgroup_free_data(struct btrfs_inode *inode,
3933			struct extent_changeset *reserved, u64 start, u64 len)
3934{
3935	return __btrfs_qgroup_release_data(inode, reserved, start, len, 1);
3936}
3937
3938/*
3939 * Release a reserved space range from io_tree only.
3940 *
3941 * Should be called when a range of pages get written to disk and corresponding
3942 * FILE_EXTENT is inserted into corresponding root.
3943 *
3944 * Since new qgroup accounting framework will only update qgroup numbers at
3945 * commit_transaction() time, its reserved space shouldn't be freed from
3946 * related qgroups.
3947 *
3948 * But we should release the range from io_tree, to allow further write to be
3949 * COWed.
3950 *
3951 * NOTE: This function may sleep for memory allocation.
3952 */
3953int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len)
3954{
3955	return __btrfs_qgroup_release_data(inode, NULL, start, len, 0);
3956}
3957
3958static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3959			      enum btrfs_qgroup_rsv_type type)
3960{
3961	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3962	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
3963		return;
3964	if (num_bytes == 0)
3965		return;
3966
3967	spin_lock(&root->qgroup_meta_rsv_lock);
3968	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
3969		root->qgroup_meta_rsv_prealloc += num_bytes;
3970	else
3971		root->qgroup_meta_rsv_pertrans += num_bytes;
3972	spin_unlock(&root->qgroup_meta_rsv_lock);
3973}
3974
3975static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3976			     enum btrfs_qgroup_rsv_type type)
3977{
3978	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3979	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
3980		return 0;
3981	if (num_bytes == 0)
3982		return 0;
3983
3984	spin_lock(&root->qgroup_meta_rsv_lock);
3985	if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
3986		num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
3987				  num_bytes);
3988		root->qgroup_meta_rsv_prealloc -= num_bytes;
3989	} else {
3990		num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
3991				  num_bytes);
3992		root->qgroup_meta_rsv_pertrans -= num_bytes;
3993	}
3994	spin_unlock(&root->qgroup_meta_rsv_lock);
3995	return num_bytes;
3996}
3997
3998int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
3999			      enum btrfs_qgroup_rsv_type type, bool enforce)
4000{
4001	struct btrfs_fs_info *fs_info = root->fs_info;
4002	int ret;
4003
4004	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
4005	    !is_fstree(root->root_key.objectid) || num_bytes == 0)
4006		return 0;
4007
4008	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4009	trace_qgroup_meta_reserve(root, (s64)num_bytes, type);
4010	ret = qgroup_reserve(root, num_bytes, enforce, type);
4011	if (ret < 0)
4012		return ret;
4013	/*
4014	 * Record what we have reserved into root.
4015	 *
4016	 * To avoid quota disabled->enabled underflow.
4017	 * In that case, we may try to free space we haven't reserved
4018	 * (since quota was disabled), so record what we reserved into root.
4019	 * And ensure later release won't underflow this number.
4020	 */
4021	add_root_meta_rsv(root, num_bytes, type);
4022	return ret;
4023}
4024
4025int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
4026				enum btrfs_qgroup_rsv_type type, bool enforce,
4027				bool noflush)
4028{
4029	int ret;
4030
4031	ret = btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4032	if ((ret <= 0 && ret != -EDQUOT) || noflush)
4033		return ret;
4034
4035	ret = try_flush_qgroup(root);
4036	if (ret < 0)
4037		return ret;
4038	return btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce);
4039}
4040
4041void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
4042{
4043	struct btrfs_fs_info *fs_info = root->fs_info;
4044
4045	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
4046	    !is_fstree(root->root_key.objectid))
4047		return;
4048
4049	/* TODO: Update trace point to handle such free */
4050	trace_qgroup_meta_free_all_pertrans(root);
4051	/* Special value -1 means to free all reserved space */
4052	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid, (u64)-1,
4053				  BTRFS_QGROUP_RSV_META_PERTRANS);
4054}
4055
4056void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
4057			      enum btrfs_qgroup_rsv_type type)
4058{
4059	struct btrfs_fs_info *fs_info = root->fs_info;
4060
4061	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
4062	    !is_fstree(root->root_key.objectid))
4063		return;
4064
4065	/*
4066	 * reservation for META_PREALLOC can happen before quota is enabled,
4067	 * which can lead to underflow.
4068	 * Here ensure we will only free what we really have reserved.
4069	 */
4070	num_bytes = sub_root_meta_rsv(root, num_bytes, type);
4071	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
4072	trace_qgroup_meta_reserve(root, -(s64)num_bytes, type);
4073	btrfs_qgroup_free_refroot(fs_info, root->root_key.objectid,
4074				  num_bytes, type);
4075}
4076
4077static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
4078				int num_bytes)
4079{
 
4080	struct btrfs_qgroup *qgroup;
4081	struct ulist_node *unode;
4082	struct ulist_iterator uiter;
4083	int ret = 0;
4084
4085	if (num_bytes == 0)
4086		return;
4087	if (!fs_info->quota_root)
4088		return;
4089
4090	spin_lock(&fs_info->qgroup_lock);
4091	qgroup = find_qgroup_rb(fs_info, ref_root);
4092	if (!qgroup)
4093		goto out;
4094	ulist_reinit(fs_info->qgroup_ulist);
4095	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
4096		       qgroup_to_aux(qgroup), GFP_ATOMIC);
4097	if (ret < 0)
4098		goto out;
4099	ULIST_ITER_INIT(&uiter);
4100	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
4101		struct btrfs_qgroup *qg;
4102		struct btrfs_qgroup_list *glist;
4103
4104		qg = unode_aux_to_qgroup(unode);
4105
4106		qgroup_rsv_release(fs_info, qg, num_bytes,
4107				BTRFS_QGROUP_RSV_META_PREALLOC);
4108		qgroup_rsv_add(fs_info, qg, num_bytes,
4109				BTRFS_QGROUP_RSV_META_PERTRANS);
4110		list_for_each_entry(glist, &qg->groups, next_group) {
4111			ret = ulist_add(fs_info->qgroup_ulist,
4112					glist->group->qgroupid,
4113					qgroup_to_aux(glist->group), GFP_ATOMIC);
4114			if (ret < 0)
4115				goto out;
4116		}
4117	}
4118out:
4119	spin_unlock(&fs_info->qgroup_lock);
4120}
4121
4122void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
4123{
4124	struct btrfs_fs_info *fs_info = root->fs_info;
4125
4126	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
4127	    !is_fstree(root->root_key.objectid))
4128		return;
4129	/* Same as btrfs_qgroup_free_meta_prealloc() */
4130	num_bytes = sub_root_meta_rsv(root, num_bytes,
4131				      BTRFS_QGROUP_RSV_META_PREALLOC);
4132	trace_qgroup_meta_convert(root, num_bytes);
4133	qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
4134}
4135
4136/*
4137 * Check qgroup reserved space leaking, normally at destroy inode
4138 * time
4139 */
4140void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode)
4141{
4142	struct extent_changeset changeset;
4143	struct ulist_node *unode;
4144	struct ulist_iterator iter;
4145	int ret;
4146
4147	extent_changeset_init(&changeset);
4148	ret = clear_record_extent_bits(&inode->io_tree, 0, (u64)-1,
4149			EXTENT_QGROUP_RESERVED, &changeset);
4150
4151	WARN_ON(ret < 0);
4152	if (WARN_ON(changeset.bytes_changed)) {
4153		ULIST_ITER_INIT(&iter);
4154		while ((unode = ulist_next(&changeset.range_changed, &iter))) {
4155			btrfs_warn(inode->root->fs_info,
4156		"leaking qgroup reserved space, ino: %llu, start: %llu, end: %llu",
4157				btrfs_ino(inode), unode->val, unode->aux);
4158		}
4159		btrfs_qgroup_free_refroot(inode->root->fs_info,
4160				inode->root->root_key.objectid,
4161				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
4162
4163	}
4164	extent_changeset_release(&changeset);
4165}
4166
4167void btrfs_qgroup_init_swapped_blocks(
4168	struct btrfs_qgroup_swapped_blocks *swapped_blocks)
4169{
4170	int i;
4171
4172	spin_lock_init(&swapped_blocks->lock);
4173	for (i = 0; i < BTRFS_MAX_LEVEL; i++)
4174		swapped_blocks->blocks[i] = RB_ROOT;
4175	swapped_blocks->swapped = false;
4176}
4177
4178/*
4179 * Delete all swapped blocks record of @root.
4180 * Every record here means we skipped a full subtree scan for qgroup.
4181 *
4182 * Gets called when committing one transaction.
4183 */
4184void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root)
4185{
4186	struct btrfs_qgroup_swapped_blocks *swapped_blocks;
4187	int i;
4188
4189	swapped_blocks = &root->swapped_blocks;
4190
4191	spin_lock(&swapped_blocks->lock);
4192	if (!swapped_blocks->swapped)
4193		goto out;
4194	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4195		struct rb_root *cur_root = &swapped_blocks->blocks[i];
4196		struct btrfs_qgroup_swapped_block *entry;
4197		struct btrfs_qgroup_swapped_block *next;
4198
4199		rbtree_postorder_for_each_entry_safe(entry, next, cur_root,
4200						     node)
4201			kfree(entry);
4202		swapped_blocks->blocks[i] = RB_ROOT;
4203	}
4204	swapped_blocks->swapped = false;
4205out:
4206	spin_unlock(&swapped_blocks->lock);
4207}
4208
4209/*
4210 * Add subtree roots record into @subvol_root.
4211 *
4212 * @subvol_root:	tree root of the subvolume tree get swapped
4213 * @bg:			block group under balance
4214 * @subvol_parent/slot:	pointer to the subtree root in subvolume tree
4215 * @reloc_parent/slot:	pointer to the subtree root in reloc tree
4216 *			BOTH POINTERS ARE BEFORE TREE SWAP
4217 * @last_snapshot:	last snapshot generation of the subvolume tree
4218 */
4219int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans,
4220		struct btrfs_root *subvol_root,
4221		struct btrfs_block_group *bg,
4222		struct extent_buffer *subvol_parent, int subvol_slot,
4223		struct extent_buffer *reloc_parent, int reloc_slot,
4224		u64 last_snapshot)
4225{
4226	struct btrfs_fs_info *fs_info = subvol_root->fs_info;
4227	struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks;
4228	struct btrfs_qgroup_swapped_block *block;
4229	struct rb_node **cur;
4230	struct rb_node *parent = NULL;
4231	int level = btrfs_header_level(subvol_parent) - 1;
4232	int ret = 0;
4233
4234	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
4235		return 0;
4236
4237	if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) >
4238	    btrfs_node_ptr_generation(reloc_parent, reloc_slot)) {
4239		btrfs_err_rl(fs_info,
4240		"%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu",
4241			__func__,
4242			btrfs_node_ptr_generation(subvol_parent, subvol_slot),
4243			btrfs_node_ptr_generation(reloc_parent, reloc_slot));
4244		return -EUCLEAN;
4245	}
4246
4247	block = kmalloc(sizeof(*block), GFP_NOFS);
4248	if (!block) {
4249		ret = -ENOMEM;
4250		goto out;
4251	}
4252
4253	/*
4254	 * @reloc_parent/slot is still before swap, while @block is going to
4255	 * record the bytenr after swap, so we do the swap here.
4256	 */
4257	block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot);
4258	block->subvol_generation = btrfs_node_ptr_generation(reloc_parent,
4259							     reloc_slot);
4260	block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot);
4261	block->reloc_generation = btrfs_node_ptr_generation(subvol_parent,
4262							    subvol_slot);
4263	block->last_snapshot = last_snapshot;
4264	block->level = level;
4265
4266	/*
4267	 * If we have bg == NULL, we're called from btrfs_recover_relocation(),
4268	 * no one else can modify tree blocks thus we qgroup will not change
4269	 * no matter the value of trace_leaf.
4270	 */
4271	if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA)
4272		block->trace_leaf = true;
4273	else
4274		block->trace_leaf = false;
4275	btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot);
4276
4277	/* Insert @block into @blocks */
4278	spin_lock(&blocks->lock);
4279	cur = &blocks->blocks[level].rb_node;
4280	while (*cur) {
4281		struct btrfs_qgroup_swapped_block *entry;
4282
4283		parent = *cur;
4284		entry = rb_entry(parent, struct btrfs_qgroup_swapped_block,
4285				 node);
4286
4287		if (entry->subvol_bytenr < block->subvol_bytenr) {
4288			cur = &(*cur)->rb_left;
4289		} else if (entry->subvol_bytenr > block->subvol_bytenr) {
4290			cur = &(*cur)->rb_right;
4291		} else {
4292			if (entry->subvol_generation !=
4293					block->subvol_generation ||
4294			    entry->reloc_bytenr != block->reloc_bytenr ||
4295			    entry->reloc_generation !=
4296					block->reloc_generation) {
4297				/*
4298				 * Duplicated but mismatch entry found.
4299				 * Shouldn't happen.
4300				 *
4301				 * Marking qgroup inconsistent should be enough
4302				 * for end users.
4303				 */
4304				WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
4305				ret = -EEXIST;
4306			}
4307			kfree(block);
4308			goto out_unlock;
4309		}
4310	}
4311	rb_link_node(&block->node, parent, cur);
4312	rb_insert_color(&block->node, &blocks->blocks[level]);
4313	blocks->swapped = true;
4314out_unlock:
4315	spin_unlock(&blocks->lock);
4316out:
4317	if (ret < 0)
4318		qgroup_mark_inconsistent(fs_info);
4319	return ret;
4320}
4321
4322/*
4323 * Check if the tree block is a subtree root, and if so do the needed
4324 * delayed subtree trace for qgroup.
4325 *
4326 * This is called during btrfs_cow_block().
4327 */
4328int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans,
4329					 struct btrfs_root *root,
4330					 struct extent_buffer *subvol_eb)
4331{
4332	struct btrfs_fs_info *fs_info = root->fs_info;
4333	struct btrfs_tree_parent_check check = { 0 };
4334	struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks;
4335	struct btrfs_qgroup_swapped_block *block;
4336	struct extent_buffer *reloc_eb = NULL;
4337	struct rb_node *node;
4338	bool found = false;
4339	bool swapped = false;
4340	int level = btrfs_header_level(subvol_eb);
4341	int ret = 0;
4342	int i;
4343
4344	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
4345		return 0;
4346	if (!is_fstree(root->root_key.objectid) || !root->reloc_root)
4347		return 0;
4348
4349	spin_lock(&blocks->lock);
4350	if (!blocks->swapped) {
4351		spin_unlock(&blocks->lock);
4352		return 0;
4353	}
4354	node = blocks->blocks[level].rb_node;
4355
4356	while (node) {
4357		block = rb_entry(node, struct btrfs_qgroup_swapped_block, node);
4358		if (block->subvol_bytenr < subvol_eb->start) {
4359			node = node->rb_left;
4360		} else if (block->subvol_bytenr > subvol_eb->start) {
4361			node = node->rb_right;
4362		} else {
4363			found = true;
4364			break;
4365		}
4366	}
4367	if (!found) {
4368		spin_unlock(&blocks->lock);
4369		goto out;
4370	}
4371	/* Found one, remove it from @blocks first and update blocks->swapped */
4372	rb_erase(&block->node, &blocks->blocks[level]);
4373	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
4374		if (RB_EMPTY_ROOT(&blocks->blocks[i])) {
4375			swapped = true;
4376			break;
4377		}
4378	}
4379	blocks->swapped = swapped;
4380	spin_unlock(&blocks->lock);
4381
4382	check.level = block->level;
4383	check.transid = block->reloc_generation;
4384	check.has_first_key = true;
4385	memcpy(&check.first_key, &block->first_key, sizeof(check.first_key));
4386
4387	/* Read out reloc subtree root */
4388	reloc_eb = read_tree_block(fs_info, block->reloc_bytenr, &check);
4389	if (IS_ERR(reloc_eb)) {
4390		ret = PTR_ERR(reloc_eb);
4391		reloc_eb = NULL;
4392		goto free_out;
4393	}
4394	if (!extent_buffer_uptodate(reloc_eb)) {
4395		ret = -EIO;
4396		goto free_out;
4397	}
4398
4399	ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb,
4400			block->last_snapshot, block->trace_leaf);
4401free_out:
4402	kfree(block);
4403	free_extent_buffer(reloc_eb);
4404out:
4405	if (ret < 0) {
4406		btrfs_err_rl(fs_info,
4407			     "failed to account subtree at bytenr %llu: %d",
4408			     subvol_eb->start, ret);
4409		qgroup_mark_inconsistent(fs_info);
4410	}
4411	return ret;
4412}
4413
4414void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans)
4415{
4416	struct btrfs_qgroup_extent_record *entry;
4417	struct btrfs_qgroup_extent_record *next;
4418	struct rb_root *root;
4419
4420	root = &trans->delayed_refs.dirty_extent_root;
4421	rbtree_postorder_for_each_entry_safe(entry, next, root, node) {
4422		ulist_free(entry->old_roots);
4423		kfree(entry);
4424	}
4425}
v4.17
   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
  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 fuer 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 umounting
 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,
 534				    struct btrfs_root *quota_root,
 535				    u64 src, u64 dst)
 536{
 537	int ret;
 
 538	struct btrfs_path *path;
 539	struct btrfs_key key;
 540
 541	path = btrfs_alloc_path();
 542	if (!path)
 543		return -ENOMEM;
 544
 545	key.objectid = src;
 546	key.type = BTRFS_QGROUP_RELATION_KEY;
 547	key.offset = dst;
 548
 549	ret = btrfs_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,
 558				    struct btrfs_root *quota_root,
 559				    u64 src, u64 dst)
 560{
 561	int ret;
 
 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,
 657			   struct btrfs_root *quota_root, u64 qgroupid)
 658{
 659	int ret;
 
 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_root *root,
 704				    struct btrfs_qgroup *qgroup)
 705{
 
 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, 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_root *root,
 746				   struct btrfs_qgroup *qgroup)
 747{
 
 
 748	struct btrfs_path *path;
 749	struct btrfs_key key;
 750	struct extent_buffer *l;
 751	struct btrfs_qgroup_info_item *qgroup_info;
 752	int ret;
 753	int slot;
 754
 755	if (btrfs_is_testing(root->fs_info))
 756		return 0;
 757
 758	key.objectid = 0;
 759	key.type = BTRFS_QGROUP_INFO_KEY;
 760	key.offset = qgroup->qgroupid;
 761
 762	path = btrfs_alloc_path();
 763	if (!path)
 764		return -ENOMEM;
 765
 766	ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 767	if (ret > 0)
 768		ret = -ENOENT;
 769
 770	if (ret)
 771		goto out;
 772
 773	l = path->nodes[0];
 774	slot = path->slots[0];
 775	qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
 776	btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
 777	btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
 778	btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
 779	btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
 780	btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
 781
 782	btrfs_mark_buffer_dirty(l);
 783
 784out:
 785	btrfs_free_path(path);
 786	return ret;
 787}
 788
 789static int update_qgroup_status_item(struct btrfs_trans_handle *trans,
 790				     struct btrfs_fs_info *fs_info,
 791				    struct btrfs_root *root)
 792{
 
 
 793	struct btrfs_path *path;
 794	struct btrfs_key key;
 795	struct extent_buffer *l;
 796	struct btrfs_qgroup_status_item *ptr;
 797	int ret;
 798	int slot;
 799
 800	key.objectid = 0;
 801	key.type = BTRFS_QGROUP_STATUS_KEY;
 802	key.offset = 0;
 803
 804	path = btrfs_alloc_path();
 805	if (!path)
 806		return -ENOMEM;
 807
 808	ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
 809	if (ret > 0)
 810		ret = -ENOENT;
 811
 812	if (ret)
 813		goto out;
 814
 815	l = path->nodes[0];
 816	slot = path->slots[0];
 817	ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
 818	btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
 
 819	btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
 820	btrfs_set_qgroup_status_rescan(l, ptr,
 821				fs_info->qgroup_rescan_progress.objectid);
 822
 823	btrfs_mark_buffer_dirty(l);
 824
 825out:
 826	btrfs_free_path(path);
 827	return ret;
 828}
 829
 830/*
 831 * called with qgroup_lock held
 832 */
 833static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 834				  struct btrfs_root *root)
 835{
 836	struct btrfs_path *path;
 837	struct btrfs_key key;
 838	struct extent_buffer *leaf = NULL;
 839	int ret;
 840	int nr = 0;
 841
 842	path = btrfs_alloc_path();
 843	if (!path)
 844		return -ENOMEM;
 845
 846	path->leave_spinning = 1;
 847
 848	key.objectid = 0;
 849	key.offset = 0;
 850	key.type = 0;
 851
 852	while (1) {
 853		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
 854		if (ret < 0)
 855			goto out;
 856		leaf = path->nodes[0];
 857		nr = btrfs_header_nritems(leaf);
 858		if (!nr)
 859			break;
 860		/*
 861		 * delete the leaf one by one
 862		 * since the whole tree is going
 863		 * to be deleted.
 864		 */
 865		path->slots[0] = 0;
 866		ret = btrfs_del_items(trans, root, path, 0, nr);
 867		if (ret)
 868			goto out;
 869
 870		btrfs_release_path(path);
 871	}
 872	ret = 0;
 873out:
 874	btrfs_free_path(path);
 875	return ret;
 876}
 877
 878int btrfs_quota_enable(struct btrfs_trans_handle *trans,
 879		       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	int ret = 0;
 890	int slot;
 891
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 892	mutex_lock(&fs_info->qgroup_ioctl_lock);
 893	if (fs_info->quota_root)
 894		goto out;
 895
 896	fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL);
 897	if (!fs_info->qgroup_ulist) {
 898		ret = -ENOMEM;
 899		goto out;
 900	}
 901
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 902	/*
 903	 * initially create the quota tree
 904	 */
 905	quota_root = btrfs_create_tree(trans, fs_info,
 906				       BTRFS_QUOTA_TREE_OBJECTID);
 907	if (IS_ERR(quota_root)) {
 908		ret =  PTR_ERR(quota_root);
 
 909		goto out;
 910	}
 911
 912	path = btrfs_alloc_path();
 913	if (!path) {
 914		ret = -ENOMEM;
 
 915		goto out_free_root;
 916	}
 917
 918	key.objectid = 0;
 919	key.type = BTRFS_QGROUP_STATUS_KEY;
 920	key.offset = 0;
 921
 922	ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
 923				      sizeof(*ptr));
 924	if (ret)
 
 925		goto out_free_path;
 
 926
 927	leaf = path->nodes[0];
 928	ptr = btrfs_item_ptr(leaf, path->slots[0],
 929				 struct btrfs_qgroup_status_item);
 930	btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
 931	btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
 932	fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
 933				BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
 934	btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
 
 935	btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
 936
 937	btrfs_mark_buffer_dirty(leaf);
 938
 939	key.objectid = 0;
 940	key.type = BTRFS_ROOT_REF_KEY;
 941	key.offset = 0;
 942
 943	btrfs_release_path(path);
 944	ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
 945	if (ret > 0)
 946		goto out_add_root;
 947	if (ret < 0)
 
 948		goto out_free_path;
 949
 950
 951	while (1) {
 952		slot = path->slots[0];
 953		leaf = path->nodes[0];
 954		btrfs_item_key_to_cpu(leaf, &found_key, slot);
 955
 956		if (found_key.type == BTRFS_ROOT_REF_KEY) {
 
 
 
 
 957			ret = add_qgroup_item(trans, quota_root,
 958					      found_key.offset);
 959			if (ret)
 
 960				goto out_free_path;
 
 961
 962			qgroup = add_qgroup_rb(fs_info, found_key.offset);
 963			if (IS_ERR(qgroup)) {
 964				ret = PTR_ERR(qgroup);
 
 
 
 
 
 
 965				goto out_free_path;
 966			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 967		}
 968		ret = btrfs_next_item(tree_root, path);
 969		if (ret < 0)
 
 970			goto out_free_path;
 
 971		if (ret)
 972			break;
 973	}
 974
 975out_add_root:
 976	btrfs_release_path(path);
 977	ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
 978	if (ret)
 
 979		goto out_free_path;
 
 980
 981	qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
 982	if (IS_ERR(qgroup)) {
 983		ret = PTR_ERR(qgroup);
 
 984		goto out_free_path;
 985	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 986	spin_lock(&fs_info->qgroup_lock);
 987	fs_info->quota_root = quota_root;
 988	set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
 989	spin_unlock(&fs_info->qgroup_lock);
 
 990	ret = qgroup_rescan_init(fs_info, 0, 1);
 991	if (!ret) {
 992	        qgroup_rescan_zero_tracking(fs_info);
 
 993	        btrfs_queue_work(fs_info->qgroup_rescan_workers,
 994	                         &fs_info->qgroup_rescan_work);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 995	}
 996
 997out_free_path:
 998	btrfs_free_path(path);
 999out_free_root:
1000	if (ret) {
1001		free_extent_buffer(quota_root->node);
1002		free_extent_buffer(quota_root->commit_root);
1003		kfree(quota_root);
1004	}
1005out:
1006	if (ret) {
1007		ulist_free(fs_info->qgroup_ulist);
1008		fs_info->qgroup_ulist = NULL;
 
1009	}
1010	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
1011	return ret;
1012}
1013
1014int btrfs_quota_disable(struct btrfs_trans_handle *trans,
1015			struct btrfs_fs_info *fs_info)
1016{
1017	struct btrfs_root *quota_root;
 
1018	int ret = 0;
1019
 
 
 
 
 
 
 
1020	mutex_lock(&fs_info->qgroup_ioctl_lock);
1021	if (!fs_info->quota_root)
1022		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1023	clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1024	btrfs_qgroup_wait_for_completion(fs_info, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1025	spin_lock(&fs_info->qgroup_lock);
1026	quota_root = fs_info->quota_root;
1027	fs_info->quota_root = NULL;
1028	fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
 
1029	spin_unlock(&fs_info->qgroup_lock);
1030
1031	btrfs_free_qgroup_config(fs_info);
1032
1033	ret = btrfs_clean_quota_tree(trans, quota_root);
1034	if (ret)
 
1035		goto out;
 
1036
1037	ret = btrfs_del_root(trans, fs_info, &quota_root->root_key);
1038	if (ret)
 
1039		goto out;
 
1040
1041	list_del(&quota_root->dirty_list);
1042
1043	btrfs_tree_lock(quota_root->node);
1044	clean_tree_block(fs_info, quota_root->node);
1045	btrfs_tree_unlock(quota_root->node);
1046	btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
 
 
 
1047
1048	free_extent_buffer(quota_root->node);
1049	free_extent_buffer(quota_root->commit_root);
1050	kfree(quota_root);
1051out:
1052	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
1053	return ret;
1054}
1055
1056static void qgroup_dirty(struct btrfs_fs_info *fs_info,
1057			 struct btrfs_qgroup *qgroup)
1058{
1059	if (list_empty(&qgroup->dirty))
1060		list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
1061}
1062
1063/*
1064 * The easy accounting, we're updating qgroup relationship whose child qgroup
1065 * only has exclusive extents.
1066 *
1067 * In this case, all exclsuive extents will also be exlusive for parent, so
1068 * excl/rfer just get added/removed.
1069 *
1070 * So is qgroup reservation space, which should also be added/removed to
1071 * parent.
1072 * Or when child tries to release reservation space, parent will underflow its
1073 * reservation (for relationship adding case).
1074 *
1075 * Caller should hold fs_info->qgroup_lock.
1076 */
1077static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
1078				    struct ulist *tmp, u64 ref_root,
1079				    struct btrfs_qgroup *src, int sign)
1080{
1081	struct btrfs_qgroup *qgroup;
1082	struct btrfs_qgroup_list *glist;
1083	struct ulist_node *unode;
1084	struct ulist_iterator uiter;
1085	u64 num_bytes = src->excl;
1086	int ret = 0;
1087
1088	qgroup = find_qgroup_rb(fs_info, ref_root);
1089	if (!qgroup)
1090		goto out;
1091
1092	qgroup->rfer += sign * num_bytes;
1093	qgroup->rfer_cmpr += sign * num_bytes;
1094
1095	WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1096	qgroup->excl += sign * num_bytes;
1097	qgroup->excl_cmpr += sign * num_bytes;
1098
1099	if (sign > 0)
1100		qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1101	else
1102		qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1103
1104	qgroup_dirty(fs_info, qgroup);
1105
1106	/* Get all of the parent groups that contain this qgroup */
1107	list_for_each_entry(glist, &qgroup->groups, next_group) {
1108		ret = ulist_add(tmp, glist->group->qgroupid,
1109				qgroup_to_aux(glist->group), GFP_ATOMIC);
1110		if (ret < 0)
1111			goto out;
1112	}
1113
1114	/* Iterate all of the parents and adjust their reference counts */
1115	ULIST_ITER_INIT(&uiter);
1116	while ((unode = ulist_next(tmp, &uiter))) {
1117		qgroup = unode_aux_to_qgroup(unode);
1118		qgroup->rfer += sign * num_bytes;
1119		qgroup->rfer_cmpr += sign * num_bytes;
1120		WARN_ON(sign < 0 && qgroup->excl < num_bytes);
1121		qgroup->excl += sign * num_bytes;
1122		if (sign > 0)
1123			qgroup_rsv_add_by_qgroup(fs_info, qgroup, src);
1124		else
1125			qgroup_rsv_release_by_qgroup(fs_info, qgroup, src);
1126		qgroup->excl_cmpr += sign * num_bytes;
1127		qgroup_dirty(fs_info, qgroup);
1128
1129		/* Add any parents of the parents */
1130		list_for_each_entry(glist, &qgroup->groups, next_group) {
1131			ret = ulist_add(tmp, glist->group->qgroupid,
1132					qgroup_to_aux(glist->group), GFP_ATOMIC);
1133			if (ret < 0)
1134				goto out;
1135		}
1136	}
1137	ret = 0;
1138out:
1139	return ret;
1140}
1141
1142
1143/*
1144 * Quick path for updating qgroup with only excl refs.
1145 *
1146 * In that case, just update all parent will be enough.
1147 * Or we needs to do a full rescan.
1148 * Caller should also hold fs_info->qgroup_lock.
1149 *
1150 * Return 0 for quick update, return >0 for need to full rescan
1151 * and mark INCONSISTENT flag.
1152 * Return < 0 for other error.
1153 */
1154static int quick_update_accounting(struct btrfs_fs_info *fs_info,
1155				   struct ulist *tmp, u64 src, u64 dst,
1156				   int sign)
1157{
1158	struct btrfs_qgroup *qgroup;
1159	int ret = 1;
1160	int err = 0;
1161
1162	qgroup = find_qgroup_rb(fs_info, src);
1163	if (!qgroup)
1164		goto out;
1165	if (qgroup->excl == qgroup->rfer) {
1166		ret = 0;
1167		err = __qgroup_excl_accounting(fs_info, tmp, dst,
1168					       qgroup, sign);
1169		if (err < 0) {
1170			ret = err;
1171			goto out;
1172		}
1173	}
1174out:
1175	if (ret)
1176		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1177	return ret;
1178}
1179
1180int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
1181			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1182{
1183	struct btrfs_root *quota_root;
1184	struct btrfs_qgroup *parent;
1185	struct btrfs_qgroup *member;
1186	struct btrfs_qgroup_list *list;
1187	struct ulist *tmp;
 
1188	int ret = 0;
1189
1190	/* Check the level of src and dst first */
1191	if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
1192		return -EINVAL;
1193
 
 
1194	tmp = ulist_alloc(GFP_KERNEL);
 
1195	if (!tmp)
1196		return -ENOMEM;
1197
1198	mutex_lock(&fs_info->qgroup_ioctl_lock);
1199	quota_root = fs_info->quota_root;
1200	if (!quota_root) {
1201		ret = -EINVAL;
1202		goto out;
1203	}
1204	member = find_qgroup_rb(fs_info, src);
1205	parent = find_qgroup_rb(fs_info, dst);
1206	if (!member || !parent) {
1207		ret = -EINVAL;
1208		goto out;
1209	}
1210
1211	/* check if such qgroup relation exist firstly */
1212	list_for_each_entry(list, &member->groups, next_group) {
1213		if (list->group == parent) {
1214			ret = -EEXIST;
1215			goto out;
1216		}
1217	}
1218
1219	ret = add_qgroup_relation_item(trans, quota_root, src, dst);
1220	if (ret)
1221		goto out;
1222
1223	ret = add_qgroup_relation_item(trans, quota_root, dst, src);
1224	if (ret) {
1225		del_qgroup_relation_item(trans, quota_root, src, dst);
1226		goto out;
1227	}
1228
1229	spin_lock(&fs_info->qgroup_lock);
1230	ret = add_relation_rb(fs_info, src, dst);
1231	if (ret < 0) {
1232		spin_unlock(&fs_info->qgroup_lock);
1233		goto out;
1234	}
1235	ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
1236	spin_unlock(&fs_info->qgroup_lock);
1237out:
1238	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1239	ulist_free(tmp);
1240	return ret;
1241}
1242
1243static int __del_qgroup_relation(struct btrfs_trans_handle *trans,
1244			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1245{
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	int err;
1253
 
 
1254	tmp = ulist_alloc(GFP_KERNEL);
 
1255	if (!tmp)
1256		return -ENOMEM;
1257
1258	quota_root = fs_info->quota_root;
1259	if (!quota_root) {
1260		ret = -EINVAL;
1261		goto out;
1262	}
1263
1264	member = find_qgroup_rb(fs_info, src);
1265	parent = find_qgroup_rb(fs_info, dst);
1266	if (!member || !parent) {
1267		ret = -EINVAL;
1268		goto out;
1269	}
 
 
1270
1271	/* check if such qgroup relation exist firstly */
1272	list_for_each_entry(list, &member->groups, next_group) {
1273		if (list->group == parent)
1274			goto exist;
 
 
1275	}
1276	ret = -ENOENT;
1277	goto out;
1278exist:
1279	ret = del_qgroup_relation_item(trans, quota_root, src, dst);
1280	err = del_qgroup_relation_item(trans, quota_root, dst, src);
1281	if (err && !ret)
1282		ret = err;
1283
1284	spin_lock(&fs_info->qgroup_lock);
1285	del_relation_rb(fs_info, src, dst);
1286	ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
1287	spin_unlock(&fs_info->qgroup_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1288out:
1289	ulist_free(tmp);
1290	return ret;
1291}
1292
1293int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
1294			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
1295{
 
1296	int ret = 0;
1297
1298	mutex_lock(&fs_info->qgroup_ioctl_lock);
1299	ret = __del_qgroup_relation(trans, fs_info, src, dst);
1300	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1301
1302	return ret;
1303}
1304
1305int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
1306			struct btrfs_fs_info *fs_info, u64 qgroupid)
1307{
 
1308	struct btrfs_root *quota_root;
1309	struct btrfs_qgroup *qgroup;
1310	int ret = 0;
1311
1312	mutex_lock(&fs_info->qgroup_ioctl_lock);
1313	quota_root = fs_info->quota_root;
1314	if (!quota_root) {
1315		ret = -EINVAL;
1316		goto out;
1317	}
 
1318	qgroup = find_qgroup_rb(fs_info, qgroupid);
1319	if (qgroup) {
1320		ret = -EEXIST;
1321		goto out;
1322	}
1323
1324	ret = add_qgroup_item(trans, quota_root, qgroupid);
1325	if (ret)
1326		goto out;
1327
1328	spin_lock(&fs_info->qgroup_lock);
1329	qgroup = add_qgroup_rb(fs_info, qgroupid);
1330	spin_unlock(&fs_info->qgroup_lock);
1331
1332	if (IS_ERR(qgroup))
1333		ret = PTR_ERR(qgroup);
 
 
 
1334out:
1335	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1336	return ret;
1337}
1338
1339int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
1340			struct btrfs_fs_info *fs_info, u64 qgroupid)
1341{
1342	struct btrfs_root *quota_root;
1343	struct btrfs_qgroup *qgroup;
1344	struct btrfs_qgroup_list *list;
1345	int ret = 0;
1346
1347	mutex_lock(&fs_info->qgroup_ioctl_lock);
1348	quota_root = fs_info->quota_root;
1349	if (!quota_root) {
1350		ret = -EINVAL;
1351		goto out;
1352	}
1353
1354	qgroup = find_qgroup_rb(fs_info, qgroupid);
1355	if (!qgroup) {
1356		ret = -ENOENT;
1357		goto out;
1358	} else {
1359		/* check if there are no children of this qgroup */
1360		if (!list_empty(&qgroup->members)) {
1361			ret = -EBUSY;
1362			goto out;
1363		}
1364	}
1365	ret = del_qgroup_item(trans, quota_root, qgroupid);
 
 
 
 
 
 
 
1366	if (ret && ret != -ENOENT)
1367		goto out;
1368
1369	while (!list_empty(&qgroup->groups)) {
1370		list = list_first_entry(&qgroup->groups,
1371					struct btrfs_qgroup_list, next_group);
1372		ret = __del_qgroup_relation(trans, fs_info,
1373					   qgroupid,
1374					   list->group->qgroupid);
1375		if (ret)
1376			goto out;
1377	}
1378
1379	spin_lock(&fs_info->qgroup_lock);
1380	del_qgroup_rb(fs_info, qgroupid);
1381	spin_unlock(&fs_info->qgroup_lock);
 
 
 
 
 
 
 
 
1382out:
1383	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1384	return ret;
1385}
1386
1387int btrfs_limit_qgroup(struct btrfs_trans_handle *trans,
1388		       struct btrfs_fs_info *fs_info, u64 qgroupid,
1389		       struct btrfs_qgroup_limit *limit)
1390{
1391	struct btrfs_root *quota_root;
1392	struct btrfs_qgroup *qgroup;
1393	int ret = 0;
1394	/* Sometimes we would want to clear the limit on this qgroup.
1395	 * To meet this requirement, we treat the -1 as a special value
1396	 * which tell kernel to clear the limit on this qgroup.
1397	 */
1398	const u64 CLEAR_VALUE = -1;
1399
1400	mutex_lock(&fs_info->qgroup_ioctl_lock);
1401	quota_root = fs_info->quota_root;
1402	if (!quota_root) {
1403		ret = -EINVAL;
1404		goto out;
1405	}
1406
1407	qgroup = find_qgroup_rb(fs_info, qgroupid);
1408	if (!qgroup) {
1409		ret = -ENOENT;
1410		goto out;
1411	}
1412
1413	spin_lock(&fs_info->qgroup_lock);
1414	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) {
1415		if (limit->max_rfer == CLEAR_VALUE) {
1416			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1417			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
1418			qgroup->max_rfer = 0;
1419		} else {
1420			qgroup->max_rfer = limit->max_rfer;
1421		}
1422	}
1423	if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
1424		if (limit->max_excl == CLEAR_VALUE) {
1425			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1426			limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
1427			qgroup->max_excl = 0;
1428		} else {
1429			qgroup->max_excl = limit->max_excl;
1430		}
1431	}
1432	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
1433		if (limit->rsv_rfer == CLEAR_VALUE) {
1434			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1435			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
1436			qgroup->rsv_rfer = 0;
1437		} else {
1438			qgroup->rsv_rfer = limit->rsv_rfer;
1439		}
1440	}
1441	if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
1442		if (limit->rsv_excl == CLEAR_VALUE) {
1443			qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1444			limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
1445			qgroup->rsv_excl = 0;
1446		} else {
1447			qgroup->rsv_excl = limit->rsv_excl;
1448		}
1449	}
1450	qgroup->lim_flags |= limit->flags;
1451
1452	spin_unlock(&fs_info->qgroup_lock);
1453
1454	ret = update_qgroup_limit_item(trans, quota_root, qgroup);
1455	if (ret) {
1456		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1457		btrfs_info(fs_info, "unable to update quota limit for %llu",
1458		       qgroupid);
1459	}
1460
1461out:
1462	mutex_unlock(&fs_info->qgroup_ioctl_lock);
1463	return ret;
1464}
1465
1466int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info,
1467				struct btrfs_delayed_ref_root *delayed_refs,
1468				struct btrfs_qgroup_extent_record *record)
1469{
1470	struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
1471	struct rb_node *parent_node = NULL;
1472	struct btrfs_qgroup_extent_record *entry;
1473	u64 bytenr = record->bytenr;
1474
1475	lockdep_assert_held(&delayed_refs->lock);
1476	trace_btrfs_qgroup_trace_extent(fs_info, record);
1477
1478	while (*p) {
1479		parent_node = *p;
1480		entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
1481				 node);
1482		if (bytenr < entry->bytenr)
1483			p = &(*p)->rb_left;
1484		else if (bytenr > entry->bytenr)
1485			p = &(*p)->rb_right;
1486		else
 
 
 
 
 
1487			return 1;
 
1488	}
1489
1490	rb_link_node(&record->node, parent_node, p);
1491	rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
1492	return 0;
1493}
1494
1495int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info,
1496				   struct btrfs_qgroup_extent_record *qrecord)
1497{
1498	struct ulist *old_root;
1499	u64 bytenr = qrecord->bytenr;
1500	int ret;
1501
1502	ret = btrfs_find_all_roots(NULL, fs_info, bytenr, 0, &old_root, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1503	if (ret < 0) {
1504		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
1505		btrfs_warn(fs_info,
1506"error accounting new delayed refs extent (err code: %d), quota inconsistent",
1507			ret);
1508		return 0;
1509	}
1510
1511	/*
1512	 * Here we don't need to get the lock of
1513	 * trans->transaction->delayed_refs, since inserted qrecord won't
1514	 * be deleted, only qrecord->node may be modified (new qrecord insert)
1515	 *
1516	 * So modifying qrecord->old_roots is safe here
1517	 */
1518	qrecord->old_roots = old_root;
1519	return 0;
1520}
1521
1522int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans,
1523		struct btrfs_fs_info *fs_info, u64 bytenr, u64 num_bytes,
1524		gfp_t gfp_flag)
1525{
 
1526	struct btrfs_qgroup_extent_record *record;
1527	struct btrfs_delayed_ref_root *delayed_refs;
1528	int ret;
1529
1530	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)
1531	    || bytenr == 0 || num_bytes == 0)
1532		return 0;
1533	if (WARN_ON(trans == NULL))
1534		return -EINVAL;
1535	record = kmalloc(sizeof(*record), gfp_flag);
1536	if (!record)
1537		return -ENOMEM;
1538
1539	delayed_refs = &trans->transaction->delayed_refs;
1540	record->bytenr = bytenr;
1541	record->num_bytes = num_bytes;
1542	record->old_roots = NULL;
1543
1544	spin_lock(&delayed_refs->lock);
1545	ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record);
1546	spin_unlock(&delayed_refs->lock);
1547	if (ret > 0) {
1548		kfree(record);
1549		return 0;
1550	}
1551	return btrfs_qgroup_trace_extent_post(fs_info, record);
1552}
1553
1554int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
1555				  struct btrfs_fs_info *fs_info,
1556				  struct extent_buffer *eb)
1557{
 
1558	int nr = btrfs_header_nritems(eb);
1559	int i, extent_type, ret;
1560	struct btrfs_key key;
1561	struct btrfs_file_extent_item *fi;
1562	u64 bytenr, num_bytes;
1563
1564	/* We can be called directly from walk_up_proc() */
1565	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1566		return 0;
1567
1568	for (i = 0; i < nr; i++) {
1569		btrfs_item_key_to_cpu(eb, &key, i);
1570
1571		if (key.type != BTRFS_EXTENT_DATA_KEY)
1572			continue;
1573
1574		fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
1575		/* filter out non qgroup-accountable extents  */
1576		extent_type = btrfs_file_extent_type(eb, fi);
1577
1578		if (extent_type == BTRFS_FILE_EXTENT_INLINE)
1579			continue;
1580
1581		bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
1582		if (!bytenr)
1583			continue;
1584
1585		num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
1586
1587		ret = btrfs_qgroup_trace_extent(trans, fs_info, bytenr,
1588						num_bytes, GFP_NOFS);
1589		if (ret)
1590			return ret;
1591	}
1592	cond_resched();
1593	return 0;
1594}
1595
1596/*
1597 * Walk up the tree from the bottom, freeing leaves and any interior
1598 * nodes which have had all slots visited. If a node (leaf or
1599 * interior) is freed, the node above it will have it's slot
1600 * incremented. The root node will never be freed.
1601 *
1602 * At the end of this function, we should have a path which has all
1603 * slots incremented to the next position for a search. If we need to
1604 * read a new node it will be NULL and the node above it will have the
1605 * correct slot selected for a later read.
1606 *
1607 * If we increment the root nodes slot counter past the number of
1608 * elements, 1 is returned to signal completion of the search.
1609 */
1610static int adjust_slots_upwards(struct btrfs_path *path, int root_level)
1611{
1612	int level = 0;
1613	int nr, slot;
1614	struct extent_buffer *eb;
1615
1616	if (root_level == 0)
1617		return 1;
1618
1619	while (level <= root_level) {
1620		eb = path->nodes[level];
1621		nr = btrfs_header_nritems(eb);
1622		path->slots[level]++;
1623		slot = path->slots[level];
1624		if (slot >= nr || level == 0) {
1625			/*
1626			 * Don't free the root -  we will detect this
1627			 * condition after our loop and return a
1628			 * positive value for caller to stop walking the tree.
1629			 */
1630			if (level != root_level) {
1631				btrfs_tree_unlock_rw(eb, path->locks[level]);
1632				path->locks[level] = 0;
1633
1634				free_extent_buffer(eb);
1635				path->nodes[level] = NULL;
1636				path->slots[level] = 0;
1637			}
1638		} else {
1639			/*
1640			 * We have a valid slot to walk back down
1641			 * from. Stop here so caller can process these
1642			 * new nodes.
1643			 */
1644			break;
1645		}
1646
1647		level++;
1648	}
1649
1650	eb = path->nodes[root_level];
1651	if (path->slots[root_level] >= btrfs_header_nritems(eb))
1652		return 1;
1653
1654	return 0;
1655}
1656
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1657int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
1658			       struct btrfs_root *root,
1659			       struct extent_buffer *root_eb,
1660			       u64 root_gen, int root_level)
1661{
1662	struct btrfs_fs_info *fs_info = root->fs_info;
1663	int ret = 0;
1664	int level;
 
1665	struct extent_buffer *eb = root_eb;
1666	struct btrfs_path *path = NULL;
1667
1668	BUG_ON(root_level < 0 || root_level >= BTRFS_MAX_LEVEL);
1669	BUG_ON(root_eb == NULL);
1670
1671	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1672		return 0;
1673
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1674	if (!extent_buffer_uptodate(root_eb)) {
1675		ret = btrfs_read_buffer(root_eb, root_gen, root_level, NULL);
 
 
 
 
 
 
1676		if (ret)
1677			goto out;
1678	}
1679
1680	if (root_level == 0) {
1681		ret = btrfs_qgroup_trace_leaf_items(trans, fs_info, root_eb);
1682		goto out;
1683	}
1684
1685	path = btrfs_alloc_path();
1686	if (!path)
1687		return -ENOMEM;
1688
1689	/*
1690	 * Walk down the tree.  Missing extent blocks are filled in as
1691	 * we go. Metadata is accounted every time we read a new
1692	 * extent block.
1693	 *
1694	 * When we reach a leaf, we account for file extent items in it,
1695	 * walk back up the tree (adjusting slot pointers as we go)
1696	 * and restart the search process.
1697	 */
1698	extent_buffer_get(root_eb); /* For path */
1699	path->nodes[root_level] = root_eb;
1700	path->slots[root_level] = 0;
1701	path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
1702walk_down:
1703	level = root_level;
1704	while (level >= 0) {
1705		if (path->nodes[level] == NULL) {
1706			struct btrfs_key first_key;
1707			int parent_slot;
1708			u64 child_gen;
1709			u64 child_bytenr;
1710
1711			/*
1712			 * We need to get child blockptr/gen from parent before
1713			 * we can read it.
1714			  */
1715			eb = path->nodes[level + 1];
1716			parent_slot = path->slots[level + 1];
1717			child_bytenr = btrfs_node_blockptr(eb, parent_slot);
1718			child_gen = btrfs_node_ptr_generation(eb, parent_slot);
1719			btrfs_node_key_to_cpu(eb, &first_key, parent_slot);
1720
1721			eb = read_tree_block(fs_info, child_bytenr, child_gen,
1722					     level, &first_key);
1723			if (IS_ERR(eb)) {
1724				ret = PTR_ERR(eb);
1725				goto out;
1726			} else if (!extent_buffer_uptodate(eb)) {
1727				free_extent_buffer(eb);
1728				ret = -EIO;
1729				goto out;
1730			}
1731
1732			path->nodes[level] = eb;
1733			path->slots[level] = 0;
1734
1735			btrfs_tree_read_lock(eb);
1736			btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
1737			path->locks[level] = BTRFS_READ_LOCK_BLOCKING;
1738
1739			ret = btrfs_qgroup_trace_extent(trans, fs_info,
1740							child_bytenr,
1741							fs_info->nodesize,
1742							GFP_NOFS);
1743			if (ret)
1744				goto out;
1745		}
1746
1747		if (level == 0) {
1748			ret = btrfs_qgroup_trace_leaf_items(trans,fs_info,
1749							   path->nodes[level]);
1750			if (ret)
1751				goto out;
1752
1753			/* Nonzero return here means we completed our search */
1754			ret = adjust_slots_upwards(path, root_level);
1755			if (ret)
1756				break;
1757
1758			/* Restart search with new slots */
1759			goto walk_down;
1760		}
1761
1762		level--;
1763	}
1764
1765	ret = 0;
1766out:
1767	btrfs_free_path(path);
1768
1769	return ret;
1770}
1771
1772#define UPDATE_NEW	0
1773#define UPDATE_OLD	1
1774/*
1775 * Walk all of the roots that points to the bytenr and adjust their refcnts.
1776 */
1777static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
1778				struct ulist *roots, struct ulist *tmp,
1779				struct ulist *qgroups, u64 seq, int update_old)
1780{
1781	struct ulist_node *unode;
1782	struct ulist_iterator uiter;
1783	struct ulist_node *tmp_unode;
1784	struct ulist_iterator tmp_uiter;
1785	struct btrfs_qgroup *qg;
1786	int ret = 0;
1787
1788	if (!roots)
1789		return 0;
1790	ULIST_ITER_INIT(&uiter);
1791	while ((unode = ulist_next(roots, &uiter))) {
1792		qg = find_qgroup_rb(fs_info, unode->val);
1793		if (!qg)
1794			continue;
1795
1796		ulist_reinit(tmp);
1797		ret = ulist_add(qgroups, qg->qgroupid, qgroup_to_aux(qg),
1798				GFP_ATOMIC);
1799		if (ret < 0)
1800			return ret;
1801		ret = ulist_add(tmp, qg->qgroupid, qgroup_to_aux(qg), GFP_ATOMIC);
1802		if (ret < 0)
1803			return ret;
1804		ULIST_ITER_INIT(&tmp_uiter);
1805		while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
1806			struct btrfs_qgroup_list *glist;
1807
1808			qg = unode_aux_to_qgroup(tmp_unode);
1809			if (update_old)
1810				btrfs_qgroup_update_old_refcnt(qg, seq, 1);
1811			else
1812				btrfs_qgroup_update_new_refcnt(qg, seq, 1);
1813			list_for_each_entry(glist, &qg->groups, next_group) {
1814				ret = ulist_add(qgroups, glist->group->qgroupid,
1815						qgroup_to_aux(glist->group),
1816						GFP_ATOMIC);
1817				if (ret < 0)
1818					return ret;
1819				ret = ulist_add(tmp, glist->group->qgroupid,
1820						qgroup_to_aux(glist->group),
1821						GFP_ATOMIC);
1822				if (ret < 0)
1823					return ret;
1824			}
1825		}
1826	}
1827	return 0;
1828}
1829
1830/*
1831 * Update qgroup rfer/excl counters.
1832 * Rfer update is easy, codes can explain themselves.
1833 *
1834 * Excl update is tricky, the update is split into 2 part.
1835 * Part 1: Possible exclusive <-> sharing detect:
1836 *	|	A	|	!A	|
1837 *  -------------------------------------
1838 *  B	|	*	|	-	|
1839 *  -------------------------------------
1840 *  !B	|	+	|	**	|
1841 *  -------------------------------------
1842 *
1843 * Conditions:
1844 * A:	cur_old_roots < nr_old_roots	(not exclusive before)
1845 * !A:	cur_old_roots == nr_old_roots	(possible exclusive before)
1846 * B:	cur_new_roots < nr_new_roots	(not exclusive now)
1847 * !B:	cur_new_roots == nr_new_roots	(possible exclusive now)
1848 *
1849 * Results:
1850 * +: Possible sharing -> exclusive	-: Possible exclusive -> sharing
1851 * *: Definitely not changed.		**: Possible unchanged.
1852 *
1853 * For !A and !B condition, the exception is cur_old/new_roots == 0 case.
1854 *
1855 * To make the logic clear, we first use condition A and B to split
1856 * combination into 4 results.
1857 *
1858 * Then, for result "+" and "-", check old/new_roots == 0 case, as in them
1859 * only on variant maybe 0.
1860 *
1861 * Lastly, check result **, since there are 2 variants maybe 0, split them
1862 * again(2x2).
1863 * But this time we don't need to consider other things, the codes and logic
1864 * is easy to understand now.
1865 */
1866static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
1867				  struct ulist *qgroups,
1868				  u64 nr_old_roots,
1869				  u64 nr_new_roots,
1870				  u64 num_bytes, u64 seq)
1871{
1872	struct ulist_node *unode;
1873	struct ulist_iterator uiter;
1874	struct btrfs_qgroup *qg;
1875	u64 cur_new_count, cur_old_count;
1876
1877	ULIST_ITER_INIT(&uiter);
1878	while ((unode = ulist_next(qgroups, &uiter))) {
1879		bool dirty = false;
1880
1881		qg = unode_aux_to_qgroup(unode);
1882		cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
1883		cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
1884
1885		trace_qgroup_update_counters(fs_info, qg->qgroupid,
1886					     cur_old_count, cur_new_count);
1887
1888		/* Rfer update part */
1889		if (cur_old_count == 0 && cur_new_count > 0) {
1890			qg->rfer += num_bytes;
1891			qg->rfer_cmpr += num_bytes;
1892			dirty = true;
1893		}
1894		if (cur_old_count > 0 && cur_new_count == 0) {
1895			qg->rfer -= num_bytes;
1896			qg->rfer_cmpr -= num_bytes;
1897			dirty = true;
1898		}
1899
1900		/* Excl update part */
1901		/* Exclusive/none -> shared case */
1902		if (cur_old_count == nr_old_roots &&
1903		    cur_new_count < nr_new_roots) {
1904			/* Exclusive -> shared */
1905			if (cur_old_count != 0) {
1906				qg->excl -= num_bytes;
1907				qg->excl_cmpr -= num_bytes;
1908				dirty = true;
1909			}
1910		}
1911
1912		/* Shared -> exclusive/none case */
1913		if (cur_old_count < nr_old_roots &&
1914		    cur_new_count == nr_new_roots) {
1915			/* Shared->exclusive */
1916			if (cur_new_count != 0) {
1917				qg->excl += num_bytes;
1918				qg->excl_cmpr += num_bytes;
1919				dirty = true;
1920			}
1921		}
1922
1923		/* Exclusive/none -> exclusive/none case */
1924		if (cur_old_count == nr_old_roots &&
1925		    cur_new_count == nr_new_roots) {
1926			if (cur_old_count == 0) {
1927				/* None -> exclusive/none */
1928
1929				if (cur_new_count != 0) {
1930					/* None -> exclusive */
1931					qg->excl += num_bytes;
1932					qg->excl_cmpr += num_bytes;
1933					dirty = true;
1934				}
1935				/* None -> none, nothing changed */
1936			} else {
1937				/* Exclusive -> exclusive/none */
1938
1939				if (cur_new_count == 0) {
1940					/* Exclusive -> none */
1941					qg->excl -= num_bytes;
1942					qg->excl_cmpr -= num_bytes;
1943					dirty = true;
1944				}
1945				/* Exclusive -> exclusive, nothing changed */
1946			}
1947		}
1948
1949		if (dirty)
1950			qgroup_dirty(fs_info, qg);
1951	}
1952	return 0;
1953}
1954
1955/*
1956 * Check if the @roots potentially is a list of fs tree roots
1957 *
1958 * Return 0 for definitely not a fs/subvol tree roots ulist
1959 * Return 1 for possible fs/subvol tree roots in the list (considering an empty
1960 *          one as well)
1961 */
1962static int maybe_fs_roots(struct ulist *roots)
1963{
1964	struct ulist_node *unode;
1965	struct ulist_iterator uiter;
1966
1967	/* Empty one, still possible for fs roots */
1968	if (!roots || roots->nnodes == 0)
1969		return 1;
1970
1971	ULIST_ITER_INIT(&uiter);
1972	unode = ulist_next(roots, &uiter);
1973	if (!unode)
1974		return 1;
1975
1976	/*
1977	 * If it contains fs tree roots, then it must belong to fs/subvol
1978	 * trees.
1979	 * If it contains a non-fs tree, it won't be shared with fs/subvol trees.
1980	 */
1981	return is_fstree(unode->val);
1982}
1983
1984int
1985btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans,
1986			    struct btrfs_fs_info *fs_info,
1987			    u64 bytenr, u64 num_bytes,
1988			    struct ulist *old_roots, struct ulist *new_roots)
1989{
 
1990	struct ulist *qgroups = NULL;
1991	struct ulist *tmp = NULL;
1992	u64 seq;
1993	u64 nr_new_roots = 0;
1994	u64 nr_old_roots = 0;
1995	int ret = 0;
1996
1997	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
1998		return 0;
 
 
 
 
 
1999
2000	if (new_roots) {
2001		if (!maybe_fs_roots(new_roots))
2002			goto out_free;
2003		nr_new_roots = new_roots->nnodes;
2004	}
2005	if (old_roots) {
2006		if (!maybe_fs_roots(old_roots))
2007			goto out_free;
2008		nr_old_roots = old_roots->nnodes;
2009	}
2010
2011	/* Quick exit, either not fs tree roots, or won't affect any qgroup */
2012	if (nr_old_roots == 0 && nr_new_roots == 0)
2013		goto out_free;
2014
2015	BUG_ON(!fs_info->quota_root);
2016
2017	trace_btrfs_qgroup_account_extent(fs_info, bytenr, num_bytes,
2018					  nr_old_roots, nr_new_roots);
2019
2020	qgroups = ulist_alloc(GFP_NOFS);
2021	if (!qgroups) {
2022		ret = -ENOMEM;
2023		goto out_free;
2024	}
2025	tmp = ulist_alloc(GFP_NOFS);
2026	if (!tmp) {
2027		ret = -ENOMEM;
2028		goto out_free;
2029	}
2030
2031	mutex_lock(&fs_info->qgroup_rescan_lock);
2032	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
2033		if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
2034			mutex_unlock(&fs_info->qgroup_rescan_lock);
2035			ret = 0;
2036			goto out_free;
2037		}
2038	}
2039	mutex_unlock(&fs_info->qgroup_rescan_lock);
2040
2041	spin_lock(&fs_info->qgroup_lock);
2042	seq = fs_info->qgroup_seq;
2043
2044	/* Update old refcnts using old_roots */
2045	ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
2046				   UPDATE_OLD);
2047	if (ret < 0)
2048		goto out;
2049
2050	/* Update new refcnts using new_roots */
2051	ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
2052				   UPDATE_NEW);
2053	if (ret < 0)
2054		goto out;
2055
2056	qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
2057			       num_bytes, seq);
2058
2059	/*
2060	 * Bump qgroup_seq to avoid seq overlap
2061	 */
2062	fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
2063out:
2064	spin_unlock(&fs_info->qgroup_lock);
2065out_free:
2066	ulist_free(tmp);
2067	ulist_free(qgroups);
2068	ulist_free(old_roots);
2069	ulist_free(new_roots);
2070	return ret;
2071}
2072
2073int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans)
2074{
2075	struct btrfs_fs_info *fs_info = trans->fs_info;
2076	struct btrfs_qgroup_extent_record *record;
2077	struct btrfs_delayed_ref_root *delayed_refs;
2078	struct ulist *new_roots = NULL;
2079	struct rb_node *node;
 
2080	u64 qgroup_to_skip;
2081	int ret = 0;
2082
2083	delayed_refs = &trans->transaction->delayed_refs;
2084	qgroup_to_skip = delayed_refs->qgroup_to_skip;
2085	while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
2086		record = rb_entry(node, struct btrfs_qgroup_extent_record,
2087				  node);
2088
 
2089		trace_btrfs_qgroup_account_extents(fs_info, record);
2090
2091		if (!ret) {
 
 
 
 
 
 
2092			/*
2093			 * Old roots should be searched when inserting qgroup
2094			 * extent record
 
 
 
 
 
 
 
 
 
 
2095			 */
2096			if (WARN_ON(!record->old_roots)) {
2097				/* Search commit root to find old_roots */
2098				ret = btrfs_find_all_roots(NULL, fs_info,
2099						record->bytenr, 0,
2100						&record->old_roots, false);
2101				if (ret < 0)
2102					goto cleanup;
 
 
2103			}
2104
 
 
 
 
 
2105			/*
2106			 * Use SEQ_LAST as time_seq to do special search, which
2107			 * doesn't lock tree or delayed_refs and search current
2108			 * root. It's safe inside commit_transaction().
2109			 */
2110			ret = btrfs_find_all_roots(trans, fs_info,
2111				record->bytenr, SEQ_LAST, &new_roots, false);
 
2112			if (ret < 0)
2113				goto cleanup;
 
2114			if (qgroup_to_skip) {
2115				ulist_del(new_roots, qgroup_to_skip, 0);
2116				ulist_del(record->old_roots, qgroup_to_skip,
2117					  0);
2118			}
2119			ret = btrfs_qgroup_account_extent(trans, fs_info,
2120					record->bytenr, record->num_bytes,
2121					record->old_roots, new_roots);
 
2122			record->old_roots = NULL;
2123			new_roots = NULL;
2124		}
2125cleanup:
2126		ulist_free(record->old_roots);
2127		ulist_free(new_roots);
2128		new_roots = NULL;
2129		rb_erase(node, &delayed_refs->dirty_extent_root);
2130		kfree(record);
2131
2132	}
 
 
2133	return ret;
2134}
2135
2136/*
2137 * called from commit_transaction. Writes all changed qgroups to disk.
2138 */
2139int btrfs_run_qgroups(struct btrfs_trans_handle *trans,
2140		      struct btrfs_fs_info *fs_info)
2141{
2142	struct btrfs_root *quota_root = fs_info->quota_root;
2143	int ret = 0;
2144
2145	if (!quota_root)
2146		return ret;
2147
2148	spin_lock(&fs_info->qgroup_lock);
2149	while (!list_empty(&fs_info->dirty_qgroups)) {
2150		struct btrfs_qgroup *qgroup;
2151		qgroup = list_first_entry(&fs_info->dirty_qgroups,
2152					  struct btrfs_qgroup, dirty);
2153		list_del_init(&qgroup->dirty);
2154		spin_unlock(&fs_info->qgroup_lock);
2155		ret = update_qgroup_info_item(trans, quota_root, qgroup);
2156		if (ret)
2157			fs_info->qgroup_flags |=
2158					BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2159		ret = update_qgroup_limit_item(trans, quota_root, qgroup);
2160		if (ret)
2161			fs_info->qgroup_flags |=
2162					BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2163		spin_lock(&fs_info->qgroup_lock);
2164	}
2165	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2166		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
2167	else
2168		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
2169	spin_unlock(&fs_info->qgroup_lock);
2170
2171	ret = update_qgroup_status_item(trans, fs_info, quota_root);
2172	if (ret)
2173		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2174
2175	return ret;
2176}
2177
2178/*
2179 * Copy the accounting information between qgroups. This is necessary
2180 * when a snapshot or a subvolume is created. Throwing an error will
2181 * cause a transaction abort so we take extra care here to only error
2182 * when a readonly fs is a reasonable outcome.
2183 */
2184int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans,
2185			 struct btrfs_fs_info *fs_info, u64 srcid, u64 objectid,
2186			 struct btrfs_qgroup_inherit *inherit)
2187{
2188	int ret = 0;
2189	int i;
2190	u64 *i_qgroups;
2191	struct btrfs_root *quota_root = fs_info->quota_root;
 
 
2192	struct btrfs_qgroup *srcgroup;
2193	struct btrfs_qgroup *dstgroup;
 
2194	u32 level_size = 0;
2195	u64 nums;
2196
2197	mutex_lock(&fs_info->qgroup_ioctl_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2198	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
2199		goto out;
2200
 
2201	if (!quota_root) {
2202		ret = -EINVAL;
2203		goto out;
2204	}
2205
2206	if (inherit) {
2207		i_qgroups = (u64 *)(inherit + 1);
2208		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
2209		       2 * inherit->num_excl_copies;
2210		for (i = 0; i < nums; ++i) {
2211			srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
2212
2213			/*
2214			 * Zero out invalid groups so we can ignore
2215			 * them later.
2216			 */
2217			if (!srcgroup ||
2218			    ((srcgroup->qgroupid >> 48) <= (objectid >> 48)))
2219				*i_qgroups = 0ULL;
2220
2221			++i_qgroups;
2222		}
2223	}
2224
2225	/*
2226	 * create a tracking group for the subvol itself
2227	 */
2228	ret = add_qgroup_item(trans, quota_root, objectid);
2229	if (ret)
2230		goto out;
2231
2232	if (srcid) {
2233		struct btrfs_root *srcroot;
2234		struct btrfs_key srckey;
2235
2236		srckey.objectid = srcid;
2237		srckey.type = BTRFS_ROOT_ITEM_KEY;
2238		srckey.offset = (u64)-1;
2239		srcroot = btrfs_read_fs_root_no_name(fs_info, &srckey);
2240		if (IS_ERR(srcroot)) {
2241			ret = PTR_ERR(srcroot);
2242			goto out;
2243		}
2244
2245		level_size = fs_info->nodesize;
2246	}
2247
2248	/*
2249	 * add qgroup to all inherited groups
2250	 */
2251	if (inherit) {
2252		i_qgroups = (u64 *)(inherit + 1);
2253		for (i = 0; i < inherit->num_qgroups; ++i, ++i_qgroups) {
2254			if (*i_qgroups == 0)
2255				continue;
2256			ret = add_qgroup_relation_item(trans, quota_root,
2257						       objectid, *i_qgroups);
2258			if (ret && ret != -EEXIST)
2259				goto out;
2260			ret = add_qgroup_relation_item(trans, quota_root,
2261						       *i_qgroups, objectid);
2262			if (ret && ret != -EEXIST)
2263				goto out;
2264		}
2265		ret = 0;
2266	}
2267
2268
2269	spin_lock(&fs_info->qgroup_lock);
2270
2271	dstgroup = add_qgroup_rb(fs_info, objectid);
2272	if (IS_ERR(dstgroup)) {
2273		ret = PTR_ERR(dstgroup);
2274		goto unlock;
2275	}
2276
2277	if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
2278		dstgroup->lim_flags = inherit->lim.flags;
2279		dstgroup->max_rfer = inherit->lim.max_rfer;
2280		dstgroup->max_excl = inherit->lim.max_excl;
2281		dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
2282		dstgroup->rsv_excl = inherit->lim.rsv_excl;
2283
2284		ret = update_qgroup_limit_item(trans, quota_root, dstgroup);
2285		if (ret) {
2286			fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2287			btrfs_info(fs_info,
2288				   "unable to update quota limit for %llu",
2289				   dstgroup->qgroupid);
2290			goto unlock;
2291		}
2292	}
2293
2294	if (srcid) {
2295		srcgroup = find_qgroup_rb(fs_info, srcid);
2296		if (!srcgroup)
2297			goto unlock;
2298
2299		/*
2300		 * We call inherit after we clone the root in order to make sure
2301		 * our counts don't go crazy, so at this point the only
2302		 * difference between the two roots should be the root node.
2303		 */
 
2304		dstgroup->rfer = srcgroup->rfer;
2305		dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
2306		dstgroup->excl = level_size;
2307		dstgroup->excl_cmpr = level_size;
2308		srcgroup->excl = level_size;
2309		srcgroup->excl_cmpr = level_size;
2310
2311		/* inherit the limit info */
2312		dstgroup->lim_flags = srcgroup->lim_flags;
2313		dstgroup->max_rfer = srcgroup->max_rfer;
2314		dstgroup->max_excl = srcgroup->max_excl;
2315		dstgroup->rsv_rfer = srcgroup->rsv_rfer;
2316		dstgroup->rsv_excl = srcgroup->rsv_excl;
2317
2318		qgroup_dirty(fs_info, dstgroup);
2319		qgroup_dirty(fs_info, srcgroup);
2320	}
2321
2322	if (!inherit)
2323		goto unlock;
2324
2325	i_qgroups = (u64 *)(inherit + 1);
2326	for (i = 0; i < inherit->num_qgroups; ++i) {
2327		if (*i_qgroups) {
2328			ret = add_relation_rb(fs_info, objectid, *i_qgroups);
2329			if (ret)
2330				goto unlock;
2331		}
2332		++i_qgroups;
 
 
 
 
 
 
 
2333	}
2334
2335	for (i = 0; i <  inherit->num_ref_copies; ++i, i_qgroups += 2) {
2336		struct btrfs_qgroup *src;
2337		struct btrfs_qgroup *dst;
2338
2339		if (!i_qgroups[0] || !i_qgroups[1])
2340			continue;
2341
2342		src = find_qgroup_rb(fs_info, i_qgroups[0]);
2343		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2344
2345		if (!src || !dst) {
2346			ret = -EINVAL;
2347			goto unlock;
2348		}
2349
2350		dst->rfer = src->rfer - level_size;
2351		dst->rfer_cmpr = src->rfer_cmpr - level_size;
 
 
 
2352	}
2353	for (i = 0; i <  inherit->num_excl_copies; ++i, i_qgroups += 2) {
2354		struct btrfs_qgroup *src;
2355		struct btrfs_qgroup *dst;
2356
2357		if (!i_qgroups[0] || !i_qgroups[1])
2358			continue;
2359
2360		src = find_qgroup_rb(fs_info, i_qgroups[0]);
2361		dst = find_qgroup_rb(fs_info, i_qgroups[1]);
2362
2363		if (!src || !dst) {
2364			ret = -EINVAL;
2365			goto unlock;
2366		}
2367
2368		dst->excl = src->excl + level_size;
2369		dst->excl_cmpr = src->excl_cmpr + level_size;
 
2370	}
2371
2372unlock:
2373	spin_unlock(&fs_info->qgroup_lock);
 
 
2374out:
2375	mutex_unlock(&fs_info->qgroup_ioctl_lock);
 
 
 
2376	return ret;
2377}
2378
2379/*
2380 * Two limits to commit transaction in advance.
2381 *
2382 * For RATIO, it will be 1/RATIO of the remaining limit
2383 * (excluding data and prealloc meta) as threshold.
2384 * For SIZE, it will be in byte unit as threshold.
2385 */
2386#define QGROUP_PERTRANS_RATIO		32
2387#define QGROUP_PERTRANS_SIZE		SZ_32M
2388static bool qgroup_check_limits(struct btrfs_fs_info *fs_info,
2389				const struct btrfs_qgroup *qg, u64 num_bytes)
2390{
2391	u64 limit;
2392	u64 threshold;
2393
2394	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
2395	    qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer)
2396		return false;
2397
2398	if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
2399	    qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl)
2400		return false;
2401
2402	/*
2403	 * Even if we passed the check, it's better to check if reservation
2404	 * for meta_pertrans is pushing us near limit.
2405	 * If there is too much pertrans reservation or it's near the limit,
2406	 * let's try commit transaction to free some, using transaction_kthread
2407	 */
2408	if ((qg->lim_flags & (BTRFS_QGROUP_LIMIT_MAX_RFER |
2409			      BTRFS_QGROUP_LIMIT_MAX_EXCL))) {
2410		if (qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL)
2411			limit = qg->max_excl;
2412		else
2413			limit = qg->max_rfer;
2414		threshold = (limit - qg->rsv.values[BTRFS_QGROUP_RSV_DATA] -
2415			    qg->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC]) /
2416			    QGROUP_PERTRANS_RATIO;
2417		threshold = min_t(u64, threshold, QGROUP_PERTRANS_SIZE);
2418
2419		/*
2420		 * Use transaction_kthread to commit transaction, so we no
2421		 * longer need to bother nested transaction nor lock context.
2422		 */
2423		if (qg->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > threshold)
2424			btrfs_commit_transaction_locksafe(fs_info);
2425	}
2426
2427	return true;
2428}
2429
2430static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
2431			  enum btrfs_qgroup_rsv_type type)
2432{
2433	struct btrfs_root *quota_root;
2434	struct btrfs_qgroup *qgroup;
2435	struct btrfs_fs_info *fs_info = root->fs_info;
2436	u64 ref_root = root->root_key.objectid;
2437	int ret = 0;
2438	struct ulist_node *unode;
2439	struct ulist_iterator uiter;
2440
2441	if (!is_fstree(ref_root))
2442		return 0;
2443
2444	if (num_bytes == 0)
2445		return 0;
2446
2447	if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) &&
2448	    capable(CAP_SYS_RESOURCE))
2449		enforce = false;
2450
2451	spin_lock(&fs_info->qgroup_lock);
2452	quota_root = fs_info->quota_root;
2453	if (!quota_root)
2454		goto out;
2455
2456	qgroup = find_qgroup_rb(fs_info, ref_root);
2457	if (!qgroup)
2458		goto out;
2459
2460	/*
2461	 * in a first step, we check all affected qgroups if any limits would
2462	 * be exceeded
2463	 */
2464	ulist_reinit(fs_info->qgroup_ulist);
2465	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2466			qgroup_to_aux(qgroup), GFP_ATOMIC);
2467	if (ret < 0)
2468		goto out;
2469	ULIST_ITER_INIT(&uiter);
2470	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2471		struct btrfs_qgroup *qg;
2472		struct btrfs_qgroup_list *glist;
2473
2474		qg = unode_aux_to_qgroup(unode);
2475
2476		if (enforce && !qgroup_check_limits(fs_info, qg, num_bytes)) {
2477			ret = -EDQUOT;
2478			goto out;
2479		}
2480
2481		list_for_each_entry(glist, &qg->groups, next_group) {
2482			ret = ulist_add(fs_info->qgroup_ulist,
2483					glist->group->qgroupid,
2484					qgroup_to_aux(glist->group), GFP_ATOMIC);
2485			if (ret < 0)
2486				goto out;
2487		}
2488	}
2489	ret = 0;
2490	/*
2491	 * no limits exceeded, now record the reservation into all qgroups
2492	 */
2493	ULIST_ITER_INIT(&uiter);
2494	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2495		struct btrfs_qgroup *qg;
2496
2497		qg = unode_aux_to_qgroup(unode);
2498
2499		trace_qgroup_update_reserve(fs_info, qg, num_bytes, type);
2500		qgroup_rsv_add(fs_info, qg, num_bytes, type);
2501	}
2502
2503out:
2504	spin_unlock(&fs_info->qgroup_lock);
2505	return ret;
2506}
2507
2508/*
2509 * Free @num_bytes of reserved space with @type for qgroup.  (Normally level 0
2510 * qgroup).
2511 *
2512 * Will handle all higher level qgroup too.
2513 *
2514 * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup.
2515 * This special case is only used for META_PERTRANS type.
2516 */
2517void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
2518			       u64 ref_root, u64 num_bytes,
2519			       enum btrfs_qgroup_rsv_type type)
2520{
2521	struct btrfs_root *quota_root;
2522	struct btrfs_qgroup *qgroup;
2523	struct ulist_node *unode;
2524	struct ulist_iterator uiter;
2525	int ret = 0;
2526
2527	if (!is_fstree(ref_root))
2528		return;
2529
2530	if (num_bytes == 0)
2531		return;
2532
2533	if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) {
2534		WARN(1, "%s: Invalid type to free", __func__);
2535		return;
2536	}
2537	spin_lock(&fs_info->qgroup_lock);
2538
2539	quota_root = fs_info->quota_root;
2540	if (!quota_root)
2541		goto out;
2542
2543	qgroup = find_qgroup_rb(fs_info, ref_root);
2544	if (!qgroup)
2545		goto out;
2546
2547	if (num_bytes == (u64)-1)
2548		/*
2549		 * We're freeing all pertrans rsv, get reserved value from
2550		 * level 0 qgroup as real num_bytes to free.
2551		 */
2552		num_bytes = qgroup->rsv.values[type];
2553
2554	ulist_reinit(fs_info->qgroup_ulist);
2555	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
2556			qgroup_to_aux(qgroup), GFP_ATOMIC);
2557	if (ret < 0)
2558		goto out;
2559	ULIST_ITER_INIT(&uiter);
2560	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
2561		struct btrfs_qgroup *qg;
2562		struct btrfs_qgroup_list *glist;
2563
2564		qg = unode_aux_to_qgroup(unode);
2565
2566		trace_qgroup_update_reserve(fs_info, qg, -(s64)num_bytes, type);
2567		qgroup_rsv_release(fs_info, qg, num_bytes, type);
2568
2569		list_for_each_entry(glist, &qg->groups, next_group) {
2570			ret = ulist_add(fs_info->qgroup_ulist,
2571					glist->group->qgroupid,
2572					qgroup_to_aux(glist->group), GFP_ATOMIC);
2573			if (ret < 0)
2574				goto out;
2575		}
2576	}
2577
2578out:
2579	spin_unlock(&fs_info->qgroup_lock);
2580}
2581
2582/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2583 * returns < 0 on error, 0 when more leafs are to be scanned.
2584 * returns 1 when done.
2585 */
2586static int
2587qgroup_rescan_leaf(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
2588		   struct btrfs_trans_handle *trans)
2589{
 
 
2590	struct btrfs_key found;
2591	struct extent_buffer *scratch_leaf = NULL;
2592	struct ulist *roots = NULL;
2593	struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
2594	u64 num_bytes;
 
2595	int slot;
2596	int ret;
2597
2598	mutex_lock(&fs_info->qgroup_rescan_lock);
2599	ret = btrfs_search_slot_for_read(fs_info->extent_root,
 
 
2600					 &fs_info->qgroup_rescan_progress,
2601					 path, 1, 0);
2602
2603	btrfs_debug(fs_info,
2604		"current progress key (%llu %u %llu), search_slot ret %d",
2605		fs_info->qgroup_rescan_progress.objectid,
2606		fs_info->qgroup_rescan_progress.type,
2607		fs_info->qgroup_rescan_progress.offset, ret);
2608
2609	if (ret) {
2610		/*
2611		 * The rescan is about to end, we will not be scanning any
2612		 * further blocks. We cannot unset the RESCAN flag here, because
2613		 * we want to commit the transaction if everything went well.
2614		 * To make the live accounting work in this phase, we set our
2615		 * scan progress pointer such that every real extent objectid
2616		 * will be smaller.
2617		 */
2618		fs_info->qgroup_rescan_progress.objectid = (u64)-1;
2619		btrfs_release_path(path);
2620		mutex_unlock(&fs_info->qgroup_rescan_lock);
2621		return ret;
2622	}
 
2623
2624	btrfs_item_key_to_cpu(path->nodes[0], &found,
2625			      btrfs_header_nritems(path->nodes[0]) - 1);
2626	fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
2627
2628	btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
2629	scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]);
2630	if (!scratch_leaf) {
2631		ret = -ENOMEM;
2632		mutex_unlock(&fs_info->qgroup_rescan_lock);
2633		goto out;
2634	}
2635	extent_buffer_get(scratch_leaf);
2636	btrfs_tree_read_lock(scratch_leaf);
2637	btrfs_set_lock_blocking_rw(scratch_leaf, BTRFS_READ_LOCK);
2638	slot = path->slots[0];
2639	btrfs_release_path(path);
2640	mutex_unlock(&fs_info->qgroup_rescan_lock);
2641
2642	for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
 
 
2643		btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
2644		if (found.type != BTRFS_EXTENT_ITEM_KEY &&
2645		    found.type != BTRFS_METADATA_ITEM_KEY)
2646			continue;
2647		if (found.type == BTRFS_METADATA_ITEM_KEY)
2648			num_bytes = fs_info->nodesize;
2649		else
2650			num_bytes = found.offset;
2651
2652		ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
2653					   &roots, false);
 
 
2654		if (ret < 0)
2655			goto out;
2656		/* For rescan, just pass old_roots as NULL */
2657		ret = btrfs_qgroup_account_extent(trans, fs_info,
2658				found.objectid, num_bytes, NULL, roots);
2659		if (ret < 0)
2660			goto out;
2661	}
2662out:
2663	if (scratch_leaf) {
2664		btrfs_tree_read_unlock_blocking(scratch_leaf);
2665		free_extent_buffer(scratch_leaf);
 
 
 
 
2666	}
2667	btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
 
2668
2669	return ret;
 
 
 
 
 
2670}
2671
2672static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
2673{
2674	struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
2675						     qgroup_rescan_work);
2676	struct btrfs_path *path;
2677	struct btrfs_trans_handle *trans = NULL;
2678	int err = -ENOMEM;
2679	int ret = 0;
 
 
2680
2681	path = btrfs_alloc_path();
2682	if (!path)
2683		goto out;
 
 
 
 
 
 
2684
2685	err = 0;
2686	while (!err && !btrfs_fs_closing(fs_info)) {
2687		trans = btrfs_start_transaction(fs_info->fs_root, 0);
2688		if (IS_ERR(trans)) {
2689			err = PTR_ERR(trans);
2690			break;
2691		}
2692		if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
2693			err = -EINTR;
2694		} else {
2695			err = qgroup_rescan_leaf(fs_info, path, trans);
2696		}
2697		if (err > 0)
2698			btrfs_commit_transaction(trans);
2699		else
2700			btrfs_end_transaction(trans);
2701	}
2702
2703out:
2704	btrfs_free_path(path);
2705
2706	mutex_lock(&fs_info->qgroup_rescan_lock);
2707	if (!btrfs_fs_closing(fs_info))
2708		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2709
2710	if (err > 0 &&
2711	    fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
2712		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2713	} else if (err < 0) {
2714		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
2715	}
2716	mutex_unlock(&fs_info->qgroup_rescan_lock);
2717
2718	/*
2719	 * only update status, since the previous part has already updated the
2720	 * qgroup info.
 
 
 
2721	 */
2722	trans = btrfs_start_transaction(fs_info->quota_root, 1);
2723	if (IS_ERR(trans)) {
2724		err = PTR_ERR(trans);
2725		btrfs_err(fs_info,
2726			  "fail to start transaction for status update: %d",
2727			  err);
2728		goto done;
 
 
 
 
2729	}
2730	ret = update_qgroup_status_item(trans, fs_info, fs_info->quota_root);
2731	if (ret < 0) {
2732		err = ret;
2733		btrfs_err(fs_info, "fail to update qgroup status: %d", err);
 
 
 
 
 
 
 
 
2734	}
 
 
 
 
 
 
 
 
2735	btrfs_end_transaction(trans);
2736
2737	if (btrfs_fs_closing(fs_info)) {
2738		btrfs_info(fs_info, "qgroup scan paused");
 
 
2739	} else if (err >= 0) {
2740		btrfs_info(fs_info, "qgroup scan completed%s",
2741			err > 0 ? " (inconsistency flag cleared)" : "");
2742	} else {
2743		btrfs_err(fs_info, "qgroup scan failed with %d", err);
2744	}
2745
2746done:
2747	mutex_lock(&fs_info->qgroup_rescan_lock);
2748	fs_info->qgroup_rescan_running = false;
2749	mutex_unlock(&fs_info->qgroup_rescan_lock);
2750	complete_all(&fs_info->qgroup_rescan_completion);
2751}
2752
2753/*
2754 * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
2755 * memory required for the rescan context.
2756 */
2757static int
2758qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
2759		   int init_flags)
2760{
2761	int ret = 0;
2762
2763	if (!init_flags &&
2764	    (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ||
2765	     !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))) {
2766		ret = -EINVAL;
2767		goto err;
 
 
 
 
 
 
 
 
 
 
 
2768	}
2769
2770	mutex_lock(&fs_info->qgroup_rescan_lock);
2771	spin_lock(&fs_info->qgroup_lock);
2772
2773	if (init_flags) {
2774		if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
 
 
2775			ret = -EINPROGRESS;
2776		else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
 
 
 
2777			ret = -EINVAL;
 
 
 
 
2778
2779		if (ret) {
2780			spin_unlock(&fs_info->qgroup_lock);
2781			mutex_unlock(&fs_info->qgroup_rescan_lock);
2782			goto err;
2783		}
2784		fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2785	}
2786
2787	memset(&fs_info->qgroup_rescan_progress, 0,
2788		sizeof(fs_info->qgroup_rescan_progress));
 
 
2789	fs_info->qgroup_rescan_progress.objectid = progress_objectid;
2790	init_completion(&fs_info->qgroup_rescan_completion);
2791	fs_info->qgroup_rescan_running = true;
2792
2793	spin_unlock(&fs_info->qgroup_lock);
2794	mutex_unlock(&fs_info->qgroup_rescan_lock);
2795
2796	memset(&fs_info->qgroup_rescan_work, 0,
2797	       sizeof(fs_info->qgroup_rescan_work));
2798	btrfs_init_work(&fs_info->qgroup_rescan_work,
2799			btrfs_qgroup_rescan_helper,
2800			btrfs_qgroup_rescan_worker, NULL, NULL);
2801
2802	if (ret) {
2803err:
2804		btrfs_info(fs_info, "qgroup_rescan_init failed with %d", ret);
2805		return ret;
2806	}
2807
2808	return 0;
2809}
2810
2811static void
2812qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
2813{
2814	struct rb_node *n;
2815	struct btrfs_qgroup *qgroup;
2816
2817	spin_lock(&fs_info->qgroup_lock);
2818	/* clear all current qgroup tracking information */
2819	for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
2820		qgroup = rb_entry(n, struct btrfs_qgroup, node);
2821		qgroup->rfer = 0;
2822		qgroup->rfer_cmpr = 0;
2823		qgroup->excl = 0;
2824		qgroup->excl_cmpr = 0;
 
2825	}
2826	spin_unlock(&fs_info->qgroup_lock);
2827}
2828
2829int
2830btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
2831{
2832	int ret = 0;
2833	struct btrfs_trans_handle *trans;
2834
2835	ret = qgroup_rescan_init(fs_info, 0, 1);
2836	if (ret)
2837		return ret;
2838
2839	/*
2840	 * We have set the rescan_progress to 0, which means no more
2841	 * delayed refs will be accounted by btrfs_qgroup_account_ref.
2842	 * However, btrfs_qgroup_account_ref may be right after its call
2843	 * to btrfs_find_all_roots, in which case it would still do the
2844	 * accounting.
2845	 * To solve this, we're committing the transaction, which will
2846	 * ensure we run all delayed refs and only after that, we are
2847	 * going to clear all tracking information for a clean start.
2848	 */
2849
2850	trans = btrfs_join_transaction(fs_info->fs_root);
2851	if (IS_ERR(trans)) {
2852		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2853		return PTR_ERR(trans);
2854	}
2855	ret = btrfs_commit_transaction(trans);
2856	if (ret) {
2857		fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
2858		return ret;
2859	}
2860
2861	qgroup_rescan_zero_tracking(fs_info);
2862
 
 
2863	btrfs_queue_work(fs_info->qgroup_rescan_workers,
2864			 &fs_info->qgroup_rescan_work);
 
2865
2866	return 0;
2867}
2868
2869int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
2870				     bool interruptible)
2871{
2872	int running;
2873	int ret = 0;
2874
2875	mutex_lock(&fs_info->qgroup_rescan_lock);
2876	spin_lock(&fs_info->qgroup_lock);
2877	running = fs_info->qgroup_rescan_running;
2878	spin_unlock(&fs_info->qgroup_lock);
2879	mutex_unlock(&fs_info->qgroup_rescan_lock);
2880
2881	if (!running)
2882		return 0;
2883
2884	if (interruptible)
2885		ret = wait_for_completion_interruptible(
2886					&fs_info->qgroup_rescan_completion);
2887	else
2888		wait_for_completion(&fs_info->qgroup_rescan_completion);
2889
2890	return ret;
2891}
2892
2893/*
2894 * this is only called from open_ctree where we're still single threaded, thus
2895 * locking is omitted here.
2896 */
2897void
2898btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
2899{
2900	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
 
 
2901		btrfs_queue_work(fs_info->qgroup_rescan_workers,
2902				 &fs_info->qgroup_rescan_work);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2903}
2904
2905/*
2906 * Reserve qgroup space for range [start, start + len).
2907 *
2908 * This function will either reserve space from related qgroups or doing
2909 * nothing if the range is already reserved.
 
 
 
2910 *
2911 * Return 0 for successful reserve
2912 * Return <0 for error (including -EQUOT)
 
 
2913 *
2914 * NOTE: this function may sleep for memory allocation.
2915 *       if btrfs_qgroup_reserve_data() is called multiple times with
2916 *       same @reserved, caller must ensure when error happens it's OK
2917 *       to free *ALL* reserved space.
2918 */
2919int btrfs_qgroup_reserve_data(struct inode *inode,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2920			struct extent_changeset **reserved_ret, u64 start,
2921			u64 len)
2922{
2923	struct btrfs_root *root = BTRFS_I(inode)->root;
2924	struct ulist_node *unode;
2925	struct ulist_iterator uiter;
2926	struct extent_changeset *reserved;
 
2927	u64 orig_reserved;
2928	u64 to_reserve;
2929	int ret;
2930
2931	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &root->fs_info->flags) ||
2932	    !is_fstree(root->objectid) || len == 0)
2933		return 0;
2934
2935	/* @reserved parameter is mandatory for qgroup */
2936	if (WARN_ON(!reserved_ret))
2937		return -EINVAL;
2938	if (!*reserved_ret) {
 
2939		*reserved_ret = extent_changeset_alloc();
2940		if (!*reserved_ret)
2941			return -ENOMEM;
2942	}
2943	reserved = *reserved_ret;
2944	/* Record already reserved space */
2945	orig_reserved = reserved->bytes_changed;
2946	ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start,
2947			start + len -1, EXTENT_QGROUP_RESERVED, reserved);
2948
2949	/* Newly reserved space */
2950	to_reserve = reserved->bytes_changed - orig_reserved;
2951	trace_btrfs_qgroup_reserve_data(inode, start, len,
2952					to_reserve, QGROUP_RESERVE);
2953	if (ret < 0)
2954		goto cleanup;
2955	ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA);
2956	if (ret < 0)
2957		goto cleanup;
2958
2959	return ret;
2960
2961cleanup:
2962	/* cleanup *ALL* already reserved ranges */
2963	ULIST_ITER_INIT(&uiter);
2964	while ((unode = ulist_next(&reserved->range_changed, &uiter)))
2965		clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val,
2966				 unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL);
2967	extent_changeset_release(reserved);
2968	return ret;
2969}
2970
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2971/* Free ranges specified by @reserved, normally in error path */
2972static int qgroup_free_reserved_data(struct inode *inode,
2973			struct extent_changeset *reserved, u64 start, u64 len)
2974{
2975	struct btrfs_root *root = BTRFS_I(inode)->root;
2976	struct ulist_node *unode;
2977	struct ulist_iterator uiter;
2978	struct extent_changeset changeset;
2979	int freed = 0;
2980	int ret;
2981
2982	extent_changeset_init(&changeset);
2983	len = round_up(start + len, root->fs_info->sectorsize);
2984	start = round_down(start, root->fs_info->sectorsize);
2985
2986	ULIST_ITER_INIT(&uiter);
2987	while ((unode = ulist_next(&reserved->range_changed, &uiter))) {
2988		u64 range_start = unode->val;
2989		/* unode->aux is the inclusive end */
2990		u64 range_len = unode->aux - range_start + 1;
2991		u64 free_start;
2992		u64 free_len;
2993
2994		extent_changeset_release(&changeset);
2995
2996		/* Only free range in range [start, start + len) */
2997		if (range_start >= start + len ||
2998		    range_start + range_len <= start)
2999			continue;
3000		free_start = max(range_start, start);
3001		free_len = min(start + len, range_start + range_len) -
3002			   free_start;
3003		/*
3004		 * TODO: To also modify reserved->ranges_reserved to reflect
3005		 * the modification.
3006		 *
3007		 * However as long as we free qgroup reserved according to
3008		 * EXTENT_QGROUP_RESERVED, we won't double free.
3009		 * So not need to rush.
3010		 */
3011		ret = clear_record_extent_bits(&BTRFS_I(inode)->io_failure_tree,
3012				free_start, free_start + free_len - 1,
3013				EXTENT_QGROUP_RESERVED, &changeset);
3014		if (ret < 0)
3015			goto out;
3016		freed += changeset.bytes_changed;
3017	}
3018	btrfs_qgroup_free_refroot(root->fs_info, root->objectid, freed,
3019				  BTRFS_QGROUP_RSV_DATA);
3020	ret = freed;
3021out:
3022	extent_changeset_release(&changeset);
3023	return ret;
3024}
3025
3026static int __btrfs_qgroup_release_data(struct inode *inode,
3027			struct extent_changeset *reserved, u64 start, u64 len,
3028			int free)
3029{
3030	struct extent_changeset changeset;
3031	int trace_op = QGROUP_RELEASE;
3032	int ret;
3033
 
 
 
3034	/* In release case, we shouldn't have @reserved */
3035	WARN_ON(!free && reserved);
3036	if (free && reserved)
3037		return qgroup_free_reserved_data(inode, reserved, start, len);
3038	extent_changeset_init(&changeset);
3039	ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, start, 
3040			start + len -1, EXTENT_QGROUP_RESERVED, &changeset);
3041	if (ret < 0)
3042		goto out;
3043
3044	if (free)
3045		trace_op = QGROUP_FREE;
3046	trace_btrfs_qgroup_release_data(inode, start, len,
3047					changeset.bytes_changed, trace_op);
3048	if (free)
3049		btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
3050				BTRFS_I(inode)->root->objectid,
3051				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3052	ret = changeset.bytes_changed;
3053out:
3054	extent_changeset_release(&changeset);
3055	return ret;
3056}
3057
3058/*
3059 * Free a reserved space range from io_tree and related qgroups
3060 *
3061 * Should be called when a range of pages get invalidated before reaching disk.
3062 * Or for error cleanup case.
3063 * if @reserved is given, only reserved range in [@start, @start + @len) will
3064 * be freed.
3065 *
3066 * For data written to disk, use btrfs_qgroup_release_data().
3067 *
3068 * NOTE: This function may sleep for memory allocation.
3069 */
3070int btrfs_qgroup_free_data(struct inode *inode,
3071			struct extent_changeset *reserved, u64 start, u64 len)
3072{
3073	return __btrfs_qgroup_release_data(inode, reserved, start, len, 1);
3074}
3075
3076/*
3077 * Release a reserved space range from io_tree only.
3078 *
3079 * Should be called when a range of pages get written to disk and corresponding
3080 * FILE_EXTENT is inserted into corresponding root.
3081 *
3082 * Since new qgroup accounting framework will only update qgroup numbers at
3083 * commit_transaction() time, its reserved space shouldn't be freed from
3084 * related qgroups.
3085 *
3086 * But we should release the range from io_tree, to allow further write to be
3087 * COWed.
3088 *
3089 * NOTE: This function may sleep for memory allocation.
3090 */
3091int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len)
3092{
3093	return __btrfs_qgroup_release_data(inode, NULL, start, len, 0);
3094}
3095
3096static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3097			      enum btrfs_qgroup_rsv_type type)
3098{
3099	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3100	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
3101		return;
3102	if (num_bytes == 0)
3103		return;
3104
3105	spin_lock(&root->qgroup_meta_rsv_lock);
3106	if (type == BTRFS_QGROUP_RSV_META_PREALLOC)
3107		root->qgroup_meta_rsv_prealloc += num_bytes;
3108	else
3109		root->qgroup_meta_rsv_pertrans += num_bytes;
3110	spin_unlock(&root->qgroup_meta_rsv_lock);
3111}
3112
3113static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes,
3114			     enum btrfs_qgroup_rsv_type type)
3115{
3116	if (type != BTRFS_QGROUP_RSV_META_PREALLOC &&
3117	    type != BTRFS_QGROUP_RSV_META_PERTRANS)
3118		return 0;
3119	if (num_bytes == 0)
3120		return 0;
3121
3122	spin_lock(&root->qgroup_meta_rsv_lock);
3123	if (type == BTRFS_QGROUP_RSV_META_PREALLOC) {
3124		num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc,
3125				  num_bytes);
3126		root->qgroup_meta_rsv_prealloc -= num_bytes;
3127	} else {
3128		num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans,
3129				  num_bytes);
3130		root->qgroup_meta_rsv_pertrans -= num_bytes;
3131	}
3132	spin_unlock(&root->qgroup_meta_rsv_lock);
3133	return num_bytes;
3134}
3135
3136int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
3137				enum btrfs_qgroup_rsv_type type, bool enforce)
3138{
3139	struct btrfs_fs_info *fs_info = root->fs_info;
3140	int ret;
3141
3142	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3143	    !is_fstree(root->objectid) || num_bytes == 0)
3144		return 0;
3145
3146	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
3147	trace_qgroup_meta_reserve(root, type, (s64)num_bytes);
3148	ret = qgroup_reserve(root, num_bytes, enforce, type);
3149	if (ret < 0)
3150		return ret;
3151	/*
3152	 * Record what we have reserved into root.
3153	 *
3154	 * To avoid quota disabled->enabled underflow.
3155	 * In that case, we may try to free space we haven't reserved
3156	 * (since quota was disabled), so record what we reserved into root.
3157	 * And ensure later release won't underflow this number.
3158	 */
3159	add_root_meta_rsv(root, num_bytes, type);
3160	return ret;
3161}
3162
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3163void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root)
3164{
3165	struct btrfs_fs_info *fs_info = root->fs_info;
3166
3167	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3168	    !is_fstree(root->objectid))
3169		return;
3170
3171	/* TODO: Update trace point to handle such free */
3172	trace_qgroup_meta_free_all_pertrans(root);
3173	/* Special value -1 means to free all reserved space */
3174	btrfs_qgroup_free_refroot(fs_info, root->objectid, (u64)-1,
3175				  BTRFS_QGROUP_RSV_META_PERTRANS);
3176}
3177
3178void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
3179			      enum btrfs_qgroup_rsv_type type)
3180{
3181	struct btrfs_fs_info *fs_info = root->fs_info;
3182
3183	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3184	    !is_fstree(root->objectid))
3185		return;
3186
3187	/*
3188	 * reservation for META_PREALLOC can happen before quota is enabled,
3189	 * which can lead to underflow.
3190	 * Here ensure we will only free what we really have reserved.
3191	 */
3192	num_bytes = sub_root_meta_rsv(root, num_bytes, type);
3193	BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize));
3194	trace_qgroup_meta_reserve(root, type, -(s64)num_bytes);
3195	btrfs_qgroup_free_refroot(fs_info, root->objectid, num_bytes, type);
 
3196}
3197
3198static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
3199				int num_bytes)
3200{
3201	struct btrfs_root *quota_root = fs_info->quota_root;
3202	struct btrfs_qgroup *qgroup;
3203	struct ulist_node *unode;
3204	struct ulist_iterator uiter;
3205	int ret = 0;
3206
3207	if (num_bytes == 0)
3208		return;
3209	if (!quota_root)
3210		return;
3211
3212	spin_lock(&fs_info->qgroup_lock);
3213	qgroup = find_qgroup_rb(fs_info, ref_root);
3214	if (!qgroup)
3215		goto out;
3216	ulist_reinit(fs_info->qgroup_ulist);
3217	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
3218		       qgroup_to_aux(qgroup), GFP_ATOMIC);
3219	if (ret < 0)
3220		goto out;
3221	ULIST_ITER_INIT(&uiter);
3222	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
3223		struct btrfs_qgroup *qg;
3224		struct btrfs_qgroup_list *glist;
3225
3226		qg = unode_aux_to_qgroup(unode);
3227
3228		qgroup_rsv_release(fs_info, qg, num_bytes,
3229				BTRFS_QGROUP_RSV_META_PREALLOC);
3230		qgroup_rsv_add(fs_info, qg, num_bytes,
3231				BTRFS_QGROUP_RSV_META_PERTRANS);
3232		list_for_each_entry(glist, &qg->groups, next_group) {
3233			ret = ulist_add(fs_info->qgroup_ulist,
3234					glist->group->qgroupid,
3235					qgroup_to_aux(glist->group), GFP_ATOMIC);
3236			if (ret < 0)
3237				goto out;
3238		}
3239	}
3240out:
3241	spin_unlock(&fs_info->qgroup_lock);
3242}
3243
3244void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
3245{
3246	struct btrfs_fs_info *fs_info = root->fs_info;
3247
3248	if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) ||
3249	    !is_fstree(root->objectid))
3250		return;
3251	/* Same as btrfs_qgroup_free_meta_prealloc() */
3252	num_bytes = sub_root_meta_rsv(root, num_bytes,
3253				      BTRFS_QGROUP_RSV_META_PREALLOC);
3254	trace_qgroup_meta_convert(root, num_bytes);
3255	qgroup_convert_meta(fs_info, root->objectid, num_bytes);
3256}
3257
3258/*
3259 * Check qgroup reserved space leaking, normally at destroy inode
3260 * time
3261 */
3262void btrfs_qgroup_check_reserved_leak(struct inode *inode)
3263{
3264	struct extent_changeset changeset;
3265	struct ulist_node *unode;
3266	struct ulist_iterator iter;
3267	int ret;
3268
3269	extent_changeset_init(&changeset);
3270	ret = clear_record_extent_bits(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
3271			EXTENT_QGROUP_RESERVED, &changeset);
3272
3273	WARN_ON(ret < 0);
3274	if (WARN_ON(changeset.bytes_changed)) {
3275		ULIST_ITER_INIT(&iter);
3276		while ((unode = ulist_next(&changeset.range_changed, &iter))) {
3277			btrfs_warn(BTRFS_I(inode)->root->fs_info,
3278				"leaking qgroup reserved space, ino: %lu, start: %llu, end: %llu",
3279				inode->i_ino, unode->val, unode->aux);
3280		}
3281		btrfs_qgroup_free_refroot(BTRFS_I(inode)->root->fs_info,
3282				BTRFS_I(inode)->root->objectid,
3283				changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA);
3284
3285	}
3286	extent_changeset_release(&changeset);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3287}