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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * This file is part of UBIFS.4 *5 * Copyright (C) 2006-2008 Nokia Corporation.6 *7 * Author: Adrian Hunter8 */9 10#include "ubifs.h"11 12/*13 * An orphan is an inode number whose inode node has been committed to the index14 * with a link count of zero. That happens when an open file is deleted15 * (unlinked) and then a commit is run. In the normal course of events the inode16 * would be deleted when the file is closed. However in the case of an unclean17 * unmount, orphans need to be accounted for. After an unclean unmount, the18 * orphans' inodes must be deleted which means either scanning the entire index19 * looking for them, or keeping a list on flash somewhere. This unit implements20 * the latter approach.21 *22 * The orphan area is a fixed number of LEBs situated between the LPT area and23 * the main area. The number of orphan area LEBs is specified when the file24 * system is created. The minimum number is 1. The size of the orphan area25 * should be so that it can hold the maximum number of orphans that are expected26 * to ever exist at one time.27 *28 * The number of orphans that can fit in a LEB is:29 *30 *         (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)31 *32 * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough.33 *34 * Orphans are accumulated in a rb-tree. When an inode's link count drops to35 * zero, the inode number is added to the rb-tree. It is removed from the tree36 * when the inode is deleted.  Any new orphans that are in the orphan tree when37 * the commit is run, are written to the orphan area in 1 or more orphan nodes.38 * If the orphan area is full, it is consolidated to make space.  There is39 * always enough space because validation prevents the user from creating more40 * than the maximum number of orphans allowed.41 */42 43static int dbg_check_orphans(struct ubifs_info *c);44 45/**46 * ubifs_add_orphan - add an orphan.47 * @c: UBIFS file-system description object48 * @inum: orphan inode number49 *50 * Add an orphan. This function is called when an inodes link count drops to51 * zero.52 */53int ubifs_add_orphan(struct ubifs_info *c, ino_t inum)54{55	struct ubifs_orphan *orphan, *o;56	struct rb_node **p, *parent = NULL;57 58	orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_NOFS);59	if (!orphan)60		return -ENOMEM;61	orphan->inum = inum;62	orphan->new = 1;63 64	spin_lock(&c->orphan_lock);65	if (c->tot_orphans >= c->max_orphans) {66		spin_unlock(&c->orphan_lock);67		kfree(orphan);68		return -ENFILE;69	}70	p = &c->orph_tree.rb_node;71	while (*p) {72		parent = *p;73		o = rb_entry(parent, struct ubifs_orphan, rb);74		if (inum < o->inum)75			p = &(*p)->rb_left;76		else if (inum > o->inum)77			p = &(*p)->rb_right;78		else {79			ubifs_err(c, "orphaned twice");80			spin_unlock(&c->orphan_lock);81			kfree(orphan);82			return -EINVAL;83		}84	}85	c->tot_orphans += 1;86	c->new_orphans += 1;87	rb_link_node(&orphan->rb, parent, p);88	rb_insert_color(&orphan->rb, &c->orph_tree);89	list_add_tail(&orphan->list, &c->orph_list);90	list_add_tail(&orphan->new_list, &c->orph_new);91 92	spin_unlock(&c->orphan_lock);93	dbg_gen("ino %lu", (unsigned long)inum);94	return 0;95}96 97static struct ubifs_orphan *lookup_orphan(struct ubifs_info *c, ino_t inum)98{99	struct ubifs_orphan *o;100	struct rb_node *p;101 102	p = c->orph_tree.rb_node;103	while (p) {104		o = rb_entry(p, struct ubifs_orphan, rb);105		if (inum < o->inum)106			p = p->rb_left;107		else if (inum > o->inum)108			p = p->rb_right;109		else {110			return o;111		}112	}113	return NULL;114}115 116static void __orphan_drop(struct ubifs_info *c, struct ubifs_orphan *o)117{118	rb_erase(&o->rb, &c->orph_tree);119	list_del(&o->list);120	c->tot_orphans -= 1;121 122	if (o->new) {123		list_del(&o->new_list);124		c->new_orphans -= 1;125	}126 127	kfree(o);128}129 130static void orphan_delete(struct ubifs_info *c, struct ubifs_orphan *orph)131{132	if (orph->del) {133		dbg_gen("deleted twice ino %lu", (unsigned long)orph->inum);134		return;135	}136 137	if (orph->cmt) {138		orph->del = 1;139		rb_erase(&orph->rb, &c->orph_tree);140		orph->dnext = c->orph_dnext;141		c->orph_dnext = orph;142		dbg_gen("delete later ino %lu", (unsigned long)orph->inum);143		return;144	}145 146	__orphan_drop(c, orph);147}148 149/**150 * ubifs_delete_orphan - delete an orphan.151 * @c: UBIFS file-system description object152 * @inum: orphan inode number153 *154 * Delete an orphan. This function is called when an inode is deleted.155 */156void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum)157{158	struct ubifs_orphan *orph;159 160	spin_lock(&c->orphan_lock);161 162	orph = lookup_orphan(c, inum);163	if (!orph) {164		spin_unlock(&c->orphan_lock);165		ubifs_err(c, "missing orphan ino %lu", (unsigned long)inum);166		dump_stack();167 168		return;169	}170 171	orphan_delete(c, orph);172 173	spin_unlock(&c->orphan_lock);174}175 176/**177 * ubifs_orphan_start_commit - start commit of orphans.178 * @c: UBIFS file-system description object179 *180 * Start commit of orphans.181 */182int ubifs_orphan_start_commit(struct ubifs_info *c)183{184	struct ubifs_orphan *orphan, **last;185 186	spin_lock(&c->orphan_lock);187	last = &c->orph_cnext;188	list_for_each_entry(orphan, &c->orph_new, new_list) {189		ubifs_assert(c, orphan->new);190		ubifs_assert(c, !orphan->cmt);191		orphan->new = 0;192		orphan->cmt = 1;193		*last = orphan;194		last = &orphan->cnext;195	}196	*last = NULL;197	c->cmt_orphans = c->new_orphans;198	c->new_orphans = 0;199	dbg_cmt("%d orphans to commit", c->cmt_orphans);200	INIT_LIST_HEAD(&c->orph_new);201	if (c->tot_orphans == 0)202		c->no_orphs = 1;203	else204		c->no_orphs = 0;205	spin_unlock(&c->orphan_lock);206	return 0;207}208 209/**210 * avail_orphs - calculate available space.211 * @c: UBIFS file-system description object212 *213 * This function returns the number of orphans that can be written in the214 * available space.215 */216static int avail_orphs(struct ubifs_info *c)217{218	int avail_lebs, avail, gap;219 220	avail_lebs = c->orph_lebs - (c->ohead_lnum - c->orph_first) - 1;221	avail = avail_lebs *222	       ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));223	gap = c->leb_size - c->ohead_offs;224	if (gap >= UBIFS_ORPH_NODE_SZ + sizeof(__le64))225		avail += (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);226	return avail;227}228 229/**230 * tot_avail_orphs - calculate total space.231 * @c: UBIFS file-system description object232 *233 * This function returns the number of orphans that can be written in half234 * the total space. That leaves half the space for adding new orphans.235 */236static int tot_avail_orphs(struct ubifs_info *c)237{238	int avail_lebs, avail;239 240	avail_lebs = c->orph_lebs;241	avail = avail_lebs *242	       ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));243	return avail / 2;244}245 246/**247 * do_write_orph_node - write a node to the orphan head.248 * @c: UBIFS file-system description object249 * @len: length of node250 * @atomic: write atomically251 *252 * This function writes a node to the orphan head from the orphan buffer. If253 * %atomic is not zero, then the write is done atomically. On success, %0 is254 * returned, otherwise a negative error code is returned.255 */256static int do_write_orph_node(struct ubifs_info *c, int len, int atomic)257{258	int err = 0;259 260	if (atomic) {261		ubifs_assert(c, c->ohead_offs == 0);262		ubifs_prepare_node(c, c->orph_buf, len, 1);263		len = ALIGN(len, c->min_io_size);264		err = ubifs_leb_change(c, c->ohead_lnum, c->orph_buf, len);265	} else {266		if (c->ohead_offs == 0) {267			/* Ensure LEB has been unmapped */268			err = ubifs_leb_unmap(c, c->ohead_lnum);269			if (err)270				return err;271		}272		err = ubifs_write_node(c, c->orph_buf, len, c->ohead_lnum,273				       c->ohead_offs);274	}275	return err;276}277 278/**279 * write_orph_node - write an orphan node.280 * @c: UBIFS file-system description object281 * @atomic: write atomically282 *283 * This function builds an orphan node from the cnext list and writes it to the284 * orphan head. On success, %0 is returned, otherwise a negative error code285 * is returned.286 */287static int write_orph_node(struct ubifs_info *c, int atomic)288{289	struct ubifs_orphan *orphan, *cnext;290	struct ubifs_orph_node *orph;291	int gap, err, len, cnt, i;292 293	ubifs_assert(c, c->cmt_orphans > 0);294	gap = c->leb_size - c->ohead_offs;295	if (gap < UBIFS_ORPH_NODE_SZ + sizeof(__le64)) {296		c->ohead_lnum += 1;297		c->ohead_offs = 0;298		gap = c->leb_size;299		if (c->ohead_lnum > c->orph_last) {300			/*301			 * We limit the number of orphans so that this should302			 * never happen.303			 */304			ubifs_err(c, "out of space in orphan area");305			return -EINVAL;306		}307	}308	cnt = (gap - UBIFS_ORPH_NODE_SZ) / sizeof(__le64);309	if (cnt > c->cmt_orphans)310		cnt = c->cmt_orphans;311	len = UBIFS_ORPH_NODE_SZ + cnt * sizeof(__le64);312	ubifs_assert(c, c->orph_buf);313	orph = c->orph_buf;314	orph->ch.node_type = UBIFS_ORPH_NODE;315	spin_lock(&c->orphan_lock);316	cnext = c->orph_cnext;317	for (i = 0; i < cnt; i++) {318		orphan = cnext;319		ubifs_assert(c, orphan->cmt);320		orph->inos[i] = cpu_to_le64(orphan->inum);321		orphan->cmt = 0;322		cnext = orphan->cnext;323		orphan->cnext = NULL;324	}325	c->orph_cnext = cnext;326	c->cmt_orphans -= cnt;327	spin_unlock(&c->orphan_lock);328	if (c->cmt_orphans)329		orph->cmt_no = cpu_to_le64(c->cmt_no);330	else331		/* Mark the last node of the commit */332		orph->cmt_no = cpu_to_le64((c->cmt_no) | (1ULL << 63));333	ubifs_assert(c, c->ohead_offs + len <= c->leb_size);334	ubifs_assert(c, c->ohead_lnum >= c->orph_first);335	ubifs_assert(c, c->ohead_lnum <= c->orph_last);336	err = do_write_orph_node(c, len, atomic);337	c->ohead_offs += ALIGN(len, c->min_io_size);338	c->ohead_offs = ALIGN(c->ohead_offs, 8);339	return err;340}341 342/**343 * write_orph_nodes - write orphan nodes until there are no more to commit.344 * @c: UBIFS file-system description object345 * @atomic: write atomically346 *347 * This function writes orphan nodes for all the orphans to commit. On success,348 * %0 is returned, otherwise a negative error code is returned.349 */350static int write_orph_nodes(struct ubifs_info *c, int atomic)351{352	int err;353 354	while (c->cmt_orphans > 0) {355		err = write_orph_node(c, atomic);356		if (err)357			return err;358	}359	if (atomic) {360		int lnum;361 362		/* Unmap any unused LEBs after consolidation */363		for (lnum = c->ohead_lnum + 1; lnum <= c->orph_last; lnum++) {364			err = ubifs_leb_unmap(c, lnum);365			if (err)366				return err;367		}368	}369	return 0;370}371 372/**373 * consolidate - consolidate the orphan area.374 * @c: UBIFS file-system description object375 *376 * This function enables consolidation by putting all the orphans into the list377 * to commit. The list is in the order that the orphans were added, and the378 * LEBs are written atomically in order, so at no time can orphans be lost by379 * an unclean unmount.380 *381 * This function returns %0 on success and a negative error code on failure.382 */383static int consolidate(struct ubifs_info *c)384{385	int tot_avail = tot_avail_orphs(c), err = 0;386 387	spin_lock(&c->orphan_lock);388	dbg_cmt("there is space for %d orphans and there are %d",389		tot_avail, c->tot_orphans);390	if (c->tot_orphans - c->new_orphans <= tot_avail) {391		struct ubifs_orphan *orphan, **last;392		int cnt = 0;393 394		/* Change the cnext list to include all non-new orphans */395		last = &c->orph_cnext;396		list_for_each_entry(orphan, &c->orph_list, list) {397			if (orphan->new)398				continue;399			orphan->cmt = 1;400			*last = orphan;401			last = &orphan->cnext;402			cnt += 1;403		}404		*last = NULL;405		ubifs_assert(c, cnt == c->tot_orphans - c->new_orphans);406		c->cmt_orphans = cnt;407		c->ohead_lnum = c->orph_first;408		c->ohead_offs = 0;409	} else {410		/*411		 * We limit the number of orphans so that this should412		 * never happen.413		 */414		ubifs_err(c, "out of space in orphan area");415		err = -EINVAL;416	}417	spin_unlock(&c->orphan_lock);418	return err;419}420 421/**422 * commit_orphans - commit orphans.423 * @c: UBIFS file-system description object424 *425 * This function commits orphans to flash. On success, %0 is returned,426 * otherwise a negative error code is returned.427 */428static int commit_orphans(struct ubifs_info *c)429{430	int avail, atomic = 0, err;431 432	ubifs_assert(c, c->cmt_orphans > 0);433	avail = avail_orphs(c);434	if (avail < c->cmt_orphans) {435		/* Not enough space to write new orphans, so consolidate */436		err = consolidate(c);437		if (err)438			return err;439		atomic = 1;440	}441	err = write_orph_nodes(c, atomic);442	return err;443}444 445/**446 * erase_deleted - erase the orphans marked for deletion.447 * @c: UBIFS file-system description object448 *449 * During commit, the orphans being committed cannot be deleted, so they are450 * marked for deletion and deleted by this function. Also, the recovery451 * adds killed orphans to the deletion list, and therefore they are deleted452 * here too.453 */454static void erase_deleted(struct ubifs_info *c)455{456	struct ubifs_orphan *orphan, *dnext;457 458	spin_lock(&c->orphan_lock);459	dnext = c->orph_dnext;460	while (dnext) {461		orphan = dnext;462		dnext = orphan->dnext;463		ubifs_assert(c, !orphan->new);464		ubifs_assert(c, orphan->del);465		list_del(&orphan->list);466		c->tot_orphans -= 1;467		dbg_gen("deleting orphan ino %lu", (unsigned long)orphan->inum);468		kfree(orphan);469	}470	c->orph_dnext = NULL;471	spin_unlock(&c->orphan_lock);472}473 474/**475 * ubifs_orphan_end_commit - end commit of orphans.476 * @c: UBIFS file-system description object477 *478 * End commit of orphans.479 */480int ubifs_orphan_end_commit(struct ubifs_info *c)481{482	int err;483 484	if (c->cmt_orphans != 0) {485		err = commit_orphans(c);486		if (err)487			return err;488	}489	erase_deleted(c);490	err = dbg_check_orphans(c);491	return err;492}493 494/**495 * ubifs_clear_orphans - erase all LEBs used for orphans.496 * @c: UBIFS file-system description object497 *498 * If recovery is not required, then the orphans from the previous session499 * are not needed. This function locates the LEBs used to record500 * orphans, and un-maps them.501 */502int ubifs_clear_orphans(struct ubifs_info *c)503{504	int lnum, err;505 506	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {507		err = ubifs_leb_unmap(c, lnum);508		if (err)509			return err;510	}511	c->ohead_lnum = c->orph_first;512	c->ohead_offs = 0;513	return 0;514}515 516/**517 * do_kill_orphans - remove orphan inodes from the index.518 * @c: UBIFS file-system description object519 * @sleb: scanned LEB520 * @last_cmt_no: cmt_no of last orphan node read is passed and returned here521 * @outofdate: whether the LEB is out of date is returned here522 * @last_flagged: whether the end orphan node is encountered523 *524 * This function is a helper to the 'kill_orphans()' function. It goes through525 * every orphan node in a LEB and for every inode number recorded, removes526 * all keys for that inode from the TNC.527 */528static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,529			   unsigned long long *last_cmt_no, int *outofdate,530			   int *last_flagged)531{532	struct ubifs_scan_node *snod;533	struct ubifs_orph_node *orph;534	struct ubifs_ino_node *ino = NULL;535	unsigned long long cmt_no;536	ino_t inum;537	int i, n, err, first = 1;538 539	ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);540	if (!ino)541		return -ENOMEM;542 543	list_for_each_entry(snod, &sleb->nodes, list) {544		if (snod->type != UBIFS_ORPH_NODE) {545			ubifs_err(c, "invalid node type %d in orphan area at %d:%d",546				  snod->type, sleb->lnum, snod->offs);547			ubifs_dump_node(c, snod->node,548					c->leb_size - snod->offs);549			err = -EINVAL;550			goto out_free;551		}552 553		orph = snod->node;554 555		/* Check commit number */556		cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX;557		/*558		 * The commit number on the master node may be less, because559		 * of a failed commit. If there are several failed commits in a560		 * row, the commit number written on orphan nodes will continue561		 * to increase (because the commit number is adjusted here) even562		 * though the commit number on the master node stays the same563		 * because the master node has not been re-written.564		 */565		if (cmt_no > c->cmt_no)566			c->cmt_no = cmt_no;567		if (cmt_no < *last_cmt_no && *last_flagged) {568			/*569			 * The last orphan node had a higher commit number and570			 * was flagged as the last written for that commit571			 * number. That makes this orphan node, out of date.572			 */573			if (!first) {574				ubifs_err(c, "out of order commit number %llu in orphan node at %d:%d",575					  cmt_no, sleb->lnum, snod->offs);576				ubifs_dump_node(c, snod->node,577						c->leb_size - snod->offs);578				err = -EINVAL;579				goto out_free;580			}581			dbg_rcvry("out of date LEB %d", sleb->lnum);582			*outofdate = 1;583			err = 0;584			goto out_free;585		}586 587		if (first)588			first = 0;589 590		n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;591		for (i = 0; i < n; i++) {592			union ubifs_key key;593 594			inum = le64_to_cpu(orph->inos[i]);595 596			ino_key_init(c, &key, inum);597			err = ubifs_tnc_lookup(c, &key, ino);598			if (err && err != -ENOENT)599				goto out_free;600 601			/*602			 * Check whether an inode can really get deleted.603			 * linkat() with O_TMPFILE allows rebirth of an inode.604			 */605			if (err == 0 && ino->nlink == 0) {606				dbg_rcvry("deleting orphaned inode %lu",607					  (unsigned long)inum);608 609				err = ubifs_tnc_remove_ino(c, inum);610				if (err)611					goto out_ro;612			}613		}614 615		*last_cmt_no = cmt_no;616		if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) {617			dbg_rcvry("last orph node for commit %llu at %d:%d",618				  cmt_no, sleb->lnum, snod->offs);619			*last_flagged = 1;620		} else621			*last_flagged = 0;622	}623 624	err = 0;625out_free:626	kfree(ino);627	return err;628 629out_ro:630	ubifs_ro_mode(c, err);631	kfree(ino);632	return err;633}634 635/**636 * kill_orphans - remove all orphan inodes from the index.637 * @c: UBIFS file-system description object638 *639 * If recovery is required, then orphan inodes recorded during the previous640 * session (which ended with an unclean unmount) must be deleted from the index.641 * This is done by updating the TNC, but since the index is not updated until642 * the next commit, the LEBs where the orphan information is recorded are not643 * erased until the next commit.644 */645static int kill_orphans(struct ubifs_info *c)646{647	unsigned long long last_cmt_no = 0;648	int lnum, err = 0, outofdate = 0, last_flagged = 0;649 650	c->ohead_lnum = c->orph_first;651	c->ohead_offs = 0;652	/* Check no-orphans flag and skip this if no orphans */653	if (c->no_orphs) {654		dbg_rcvry("no orphans");655		return 0;656	}657	/*658	 * Orph nodes always start at c->orph_first and are written to each659	 * successive LEB in turn. Generally unused LEBs will have been unmapped660	 * but may contain out of date orphan nodes if the unmap didn't go661	 * through. In addition, the last orphan node written for each commit is662	 * marked (top bit of orph->cmt_no is set to 1). It is possible that663	 * there are orphan nodes from the next commit (i.e. the commit did not664	 * complete successfully). In that case, no orphans will have been lost665	 * due to the way that orphans are written, and any orphans added will666	 * be valid orphans anyway and so can be deleted.667	 */668	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {669		struct ubifs_scan_leb *sleb;670 671		dbg_rcvry("LEB %d", lnum);672		sleb = ubifs_scan(c, lnum, 0, c->sbuf, 1);673		if (IS_ERR(sleb)) {674			if (PTR_ERR(sleb) == -EUCLEAN)675				sleb = ubifs_recover_leb(c, lnum, 0,676							 c->sbuf, -1);677			if (IS_ERR(sleb)) {678				err = PTR_ERR(sleb);679				break;680			}681		}682		err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate,683				      &last_flagged);684		if (err || outofdate) {685			ubifs_scan_destroy(sleb);686			break;687		}688		if (sleb->endpt) {689			c->ohead_lnum = lnum;690			c->ohead_offs = sleb->endpt;691		}692		ubifs_scan_destroy(sleb);693	}694	return err;695}696 697/**698 * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them.699 * @c: UBIFS file-system description object700 * @unclean: indicates recovery from unclean unmount701 * @read_only: indicates read only mount702 *703 * This function is called when mounting to erase orphans from the previous704 * session. If UBIFS was not unmounted cleanly, then the inodes recorded as705 * orphans are deleted.706 */707int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)708{709	int err = 0;710 711	c->max_orphans = tot_avail_orphs(c);712 713	if (!read_only) {714		c->orph_buf = vmalloc(c->leb_size);715		if (!c->orph_buf)716			return -ENOMEM;717	}718 719	if (unclean)720		err = kill_orphans(c);721	else if (!read_only)722		err = ubifs_clear_orphans(c);723 724	return err;725}726 727/*728 * Everything below is related to debugging.729 */730 731struct check_orphan {732	struct rb_node rb;733	ino_t inum;734};735 736struct check_info {737	unsigned long last_ino;738	unsigned long tot_inos;739	unsigned long missing;740	unsigned long long leaf_cnt;741	struct ubifs_ino_node *node;742	struct rb_root root;743};744 745static bool dbg_find_orphan(struct ubifs_info *c, ino_t inum)746{747	bool found = false;748 749	spin_lock(&c->orphan_lock);750	found = !!lookup_orphan(c, inum);751	spin_unlock(&c->orphan_lock);752 753	return found;754}755 756static int dbg_ins_check_orphan(struct rb_root *root, ino_t inum)757{758	struct check_orphan *orphan, *o;759	struct rb_node **p, *parent = NULL;760 761	orphan = kzalloc(sizeof(struct check_orphan), GFP_NOFS);762	if (!orphan)763		return -ENOMEM;764	orphan->inum = inum;765 766	p = &root->rb_node;767	while (*p) {768		parent = *p;769		o = rb_entry(parent, struct check_orphan, rb);770		if (inum < o->inum)771			p = &(*p)->rb_left;772		else if (inum > o->inum)773			p = &(*p)->rb_right;774		else {775			kfree(orphan);776			return 0;777		}778	}779	rb_link_node(&orphan->rb, parent, p);780	rb_insert_color(&orphan->rb, root);781	return 0;782}783 784static int dbg_find_check_orphan(struct rb_root *root, ino_t inum)785{786	struct check_orphan *o;787	struct rb_node *p;788 789	p = root->rb_node;790	while (p) {791		o = rb_entry(p, struct check_orphan, rb);792		if (inum < o->inum)793			p = p->rb_left;794		else if (inum > o->inum)795			p = p->rb_right;796		else797			return 1;798	}799	return 0;800}801 802static void dbg_free_check_tree(struct rb_root *root)803{804	struct check_orphan *o, *n;805 806	rbtree_postorder_for_each_entry_safe(o, n, root, rb)807		kfree(o);808}809 810static int dbg_orphan_check(struct ubifs_info *c, struct ubifs_zbranch *zbr,811			    void *priv)812{813	struct check_info *ci = priv;814	ino_t inum;815	int err;816 817	inum = key_inum(c, &zbr->key);818	if (inum != ci->last_ino) {819		/*820		 * Lowest node type is the inode node or xattr entry(when821		 * selinux/encryption is enabled), so it comes first822		 */823		if (key_type(c, &zbr->key) != UBIFS_INO_KEY &&824		    key_type(c, &zbr->key) != UBIFS_XENT_KEY)825			ubifs_err(c, "found orphan node ino %lu, type %d",826				  (unsigned long)inum, key_type(c, &zbr->key));827		ci->last_ino = inum;828		ci->tot_inos += 1;829		err = ubifs_tnc_read_node(c, zbr, ci->node);830		if (err) {831			ubifs_err(c, "node read failed, error %d", err);832			return err;833		}834		if (ci->node->nlink == 0)835			/* Must be recorded as an orphan */836			if (!dbg_find_check_orphan(&ci->root, inum) &&837			    !dbg_find_orphan(c, inum)) {838				ubifs_err(c, "missing orphan, ino %lu",839					  (unsigned long)inum);840				ci->missing += 1;841			}842	}843	ci->leaf_cnt += 1;844	return 0;845}846 847static int dbg_read_orphans(struct check_info *ci, struct ubifs_scan_leb *sleb)848{849	struct ubifs_scan_node *snod;850	struct ubifs_orph_node *orph;851	ino_t inum;852	int i, n, err;853 854	list_for_each_entry(snod, &sleb->nodes, list) {855		cond_resched();856		if (snod->type != UBIFS_ORPH_NODE)857			continue;858		orph = snod->node;859		n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;860		for (i = 0; i < n; i++) {861			inum = le64_to_cpu(orph->inos[i]);862			err = dbg_ins_check_orphan(&ci->root, inum);863			if (err)864				return err;865		}866	}867	return 0;868}869 870static int dbg_scan_orphans(struct ubifs_info *c, struct check_info *ci)871{872	int lnum, err = 0;873	void *buf;874 875	/* Check no-orphans flag and skip this if no orphans */876	if (c->no_orphs)877		return 0;878 879	buf = __vmalloc(c->leb_size, GFP_NOFS);880	if (!buf) {881		ubifs_err(c, "cannot allocate memory to check orphans");882		return 0;883	}884 885	for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {886		struct ubifs_scan_leb *sleb;887 888		sleb = ubifs_scan(c, lnum, 0, buf, 0);889		if (IS_ERR(sleb)) {890			err = PTR_ERR(sleb);891			break;892		}893 894		err = dbg_read_orphans(ci, sleb);895		ubifs_scan_destroy(sleb);896		if (err)897			break;898	}899 900	vfree(buf);901	return err;902}903 904static int dbg_check_orphans(struct ubifs_info *c)905{906	struct check_info ci;907	int err;908 909	if (!dbg_is_chk_orph(c))910		return 0;911 912	ci.last_ino = 0;913	ci.tot_inos = 0;914	ci.missing  = 0;915	ci.leaf_cnt = 0;916	ci.root = RB_ROOT;917	ci.node = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);918	if (!ci.node) {919		ubifs_err(c, "out of memory");920		return -ENOMEM;921	}922 923	err = dbg_scan_orphans(c, &ci);924	if (err)925		goto out;926 927	err = dbg_walk_index(c, &dbg_orphan_check, NULL, &ci);928	if (err) {929		ubifs_err(c, "cannot scan TNC, error %d", err);930		goto out;931	}932 933	if (ci.missing) {934		ubifs_err(c, "%lu missing orphan(s)", ci.missing);935		err = -EINVAL;936		goto out;937	}938 939	dbg_cmt("last inode number is %lu", ci.last_ino);940	dbg_cmt("total number of inodes is %lu", ci.tot_inos);941	dbg_cmt("total number of leaf nodes is %llu", ci.leaf_cnt);942 943out:944	dbg_free_check_tree(&ci.root);945	kfree(ci.node);946	return err;947}948