xref: /openbmc/linux/fs/ubifs/debug.c (revision 8f6983ab)
1 /*
2  * This file is part of UBIFS.
3  *
4  * Copyright (C) 2006-2008 Nokia Corporation
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published by
8  * the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along with
16  * this program; if not, write to the Free Software Foundation, Inc., 51
17  * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18  *
19  * Authors: Artem Bityutskiy (Битюцкий Артём)
20  *          Adrian Hunter
21  */
22 
23 /*
24  * This file implements most of the debugging stuff which is compiled in only
25  * when it is enabled. But some debugging check functions are implemented in
26  * corresponding subsystem, just because they are closely related and utilize
27  * various local functions of those subsystems.
28  */
29 
30 #include <linux/module.h>
31 #include <linux/debugfs.h>
32 #include <linux/math64.h>
33 #include <linux/uaccess.h>
34 #include <linux/random.h>
35 #include "ubifs.h"
36 
37 static DEFINE_SPINLOCK(dbg_lock);
38 
39 static const char *get_key_fmt(int fmt)
40 {
41 	switch (fmt) {
42 	case UBIFS_SIMPLE_KEY_FMT:
43 		return "simple";
44 	default:
45 		return "unknown/invalid format";
46 	}
47 }
48 
49 static const char *get_key_hash(int hash)
50 {
51 	switch (hash) {
52 	case UBIFS_KEY_HASH_R5:
53 		return "R5";
54 	case UBIFS_KEY_HASH_TEST:
55 		return "test";
56 	default:
57 		return "unknown/invalid name hash";
58 	}
59 }
60 
61 static const char *get_key_type(int type)
62 {
63 	switch (type) {
64 	case UBIFS_INO_KEY:
65 		return "inode";
66 	case UBIFS_DENT_KEY:
67 		return "direntry";
68 	case UBIFS_XENT_KEY:
69 		return "xentry";
70 	case UBIFS_DATA_KEY:
71 		return "data";
72 	case UBIFS_TRUN_KEY:
73 		return "truncate";
74 	default:
75 		return "unknown/invalid key";
76 	}
77 }
78 
79 static const char *get_dent_type(int type)
80 {
81 	switch (type) {
82 	case UBIFS_ITYPE_REG:
83 		return "file";
84 	case UBIFS_ITYPE_DIR:
85 		return "dir";
86 	case UBIFS_ITYPE_LNK:
87 		return "symlink";
88 	case UBIFS_ITYPE_BLK:
89 		return "blkdev";
90 	case UBIFS_ITYPE_CHR:
91 		return "char dev";
92 	case UBIFS_ITYPE_FIFO:
93 		return "fifo";
94 	case UBIFS_ITYPE_SOCK:
95 		return "socket";
96 	default:
97 		return "unknown/invalid type";
98 	}
99 }
100 
101 const char *dbg_snprintf_key(const struct ubifs_info *c,
102 			     const union ubifs_key *key, char *buffer, int len)
103 {
104 	char *p = buffer;
105 	int type = key_type(c, key);
106 
107 	if (c->key_fmt == UBIFS_SIMPLE_KEY_FMT) {
108 		switch (type) {
109 		case UBIFS_INO_KEY:
110 			len -= snprintf(p, len, "(%lu, %s)",
111 					(unsigned long)key_inum(c, key),
112 					get_key_type(type));
113 			break;
114 		case UBIFS_DENT_KEY:
115 		case UBIFS_XENT_KEY:
116 			len -= snprintf(p, len, "(%lu, %s, %#08x)",
117 					(unsigned long)key_inum(c, key),
118 					get_key_type(type), key_hash(c, key));
119 			break;
120 		case UBIFS_DATA_KEY:
121 			len -= snprintf(p, len, "(%lu, %s, %u)",
122 					(unsigned long)key_inum(c, key),
123 					get_key_type(type), key_block(c, key));
124 			break;
125 		case UBIFS_TRUN_KEY:
126 			len -= snprintf(p, len, "(%lu, %s)",
127 					(unsigned long)key_inum(c, key),
128 					get_key_type(type));
129 			break;
130 		default:
131 			len -= snprintf(p, len, "(bad key type: %#08x, %#08x)",
132 					key->u32[0], key->u32[1]);
133 		}
134 	} else
135 		len -= snprintf(p, len, "bad key format %d", c->key_fmt);
136 	ubifs_assert(len > 0);
137 	return p;
138 }
139 
140 const char *dbg_ntype(int type)
141 {
142 	switch (type) {
143 	case UBIFS_PAD_NODE:
144 		return "padding node";
145 	case UBIFS_SB_NODE:
146 		return "superblock node";
147 	case UBIFS_MST_NODE:
148 		return "master node";
149 	case UBIFS_REF_NODE:
150 		return "reference node";
151 	case UBIFS_INO_NODE:
152 		return "inode node";
153 	case UBIFS_DENT_NODE:
154 		return "direntry node";
155 	case UBIFS_XENT_NODE:
156 		return "xentry node";
157 	case UBIFS_DATA_NODE:
158 		return "data node";
159 	case UBIFS_TRUN_NODE:
160 		return "truncate node";
161 	case UBIFS_IDX_NODE:
162 		return "indexing node";
163 	case UBIFS_CS_NODE:
164 		return "commit start node";
165 	case UBIFS_ORPH_NODE:
166 		return "orphan node";
167 	default:
168 		return "unknown node";
169 	}
170 }
171 
172 static const char *dbg_gtype(int type)
173 {
174 	switch (type) {
175 	case UBIFS_NO_NODE_GROUP:
176 		return "no node group";
177 	case UBIFS_IN_NODE_GROUP:
178 		return "in node group";
179 	case UBIFS_LAST_OF_NODE_GROUP:
180 		return "last of node group";
181 	default:
182 		return "unknown";
183 	}
184 }
185 
186 const char *dbg_cstate(int cmt_state)
187 {
188 	switch (cmt_state) {
189 	case COMMIT_RESTING:
190 		return "commit resting";
191 	case COMMIT_BACKGROUND:
192 		return "background commit requested";
193 	case COMMIT_REQUIRED:
194 		return "commit required";
195 	case COMMIT_RUNNING_BACKGROUND:
196 		return "BACKGROUND commit running";
197 	case COMMIT_RUNNING_REQUIRED:
198 		return "commit running and required";
199 	case COMMIT_BROKEN:
200 		return "broken commit";
201 	default:
202 		return "unknown commit state";
203 	}
204 }
205 
206 const char *dbg_jhead(int jhead)
207 {
208 	switch (jhead) {
209 	case GCHD:
210 		return "0 (GC)";
211 	case BASEHD:
212 		return "1 (base)";
213 	case DATAHD:
214 		return "2 (data)";
215 	default:
216 		return "unknown journal head";
217 	}
218 }
219 
220 static void dump_ch(const struct ubifs_ch *ch)
221 {
222 	pr_err("\tmagic          %#x\n", le32_to_cpu(ch->magic));
223 	pr_err("\tcrc            %#x\n", le32_to_cpu(ch->crc));
224 	pr_err("\tnode_type      %d (%s)\n", ch->node_type,
225 	       dbg_ntype(ch->node_type));
226 	pr_err("\tgroup_type     %d (%s)\n", ch->group_type,
227 	       dbg_gtype(ch->group_type));
228 	pr_err("\tsqnum          %llu\n",
229 	       (unsigned long long)le64_to_cpu(ch->sqnum));
230 	pr_err("\tlen            %u\n", le32_to_cpu(ch->len));
231 }
232 
233 void ubifs_dump_inode(struct ubifs_info *c, const struct inode *inode)
234 {
235 	const struct ubifs_inode *ui = ubifs_inode(inode);
236 	struct qstr nm = { .name = NULL };
237 	union ubifs_key key;
238 	struct ubifs_dent_node *dent, *pdent = NULL;
239 	int count = 2;
240 
241 	pr_err("Dump in-memory inode:");
242 	pr_err("\tinode          %lu\n", inode->i_ino);
243 	pr_err("\tsize           %llu\n",
244 	       (unsigned long long)i_size_read(inode));
245 	pr_err("\tnlink          %u\n", inode->i_nlink);
246 	pr_err("\tuid            %u\n", (unsigned int)i_uid_read(inode));
247 	pr_err("\tgid            %u\n", (unsigned int)i_gid_read(inode));
248 	pr_err("\tatime          %u.%u\n",
249 	       (unsigned int)inode->i_atime.tv_sec,
250 	       (unsigned int)inode->i_atime.tv_nsec);
251 	pr_err("\tmtime          %u.%u\n",
252 	       (unsigned int)inode->i_mtime.tv_sec,
253 	       (unsigned int)inode->i_mtime.tv_nsec);
254 	pr_err("\tctime          %u.%u\n",
255 	       (unsigned int)inode->i_ctime.tv_sec,
256 	       (unsigned int)inode->i_ctime.tv_nsec);
257 	pr_err("\tcreat_sqnum    %llu\n", ui->creat_sqnum);
258 	pr_err("\txattr_size     %u\n", ui->xattr_size);
259 	pr_err("\txattr_cnt      %u\n", ui->xattr_cnt);
260 	pr_err("\txattr_names    %u\n", ui->xattr_names);
261 	pr_err("\tdirty          %u\n", ui->dirty);
262 	pr_err("\txattr          %u\n", ui->xattr);
263 	pr_err("\tbulk_read      %u\n", ui->xattr);
264 	pr_err("\tsynced_i_size  %llu\n",
265 	       (unsigned long long)ui->synced_i_size);
266 	pr_err("\tui_size        %llu\n",
267 	       (unsigned long long)ui->ui_size);
268 	pr_err("\tflags          %d\n", ui->flags);
269 	pr_err("\tcompr_type     %d\n", ui->compr_type);
270 	pr_err("\tlast_page_read %lu\n", ui->last_page_read);
271 	pr_err("\tread_in_a_row  %lu\n", ui->read_in_a_row);
272 	pr_err("\tdata_len       %d\n", ui->data_len);
273 
274 	if (!S_ISDIR(inode->i_mode))
275 		return;
276 
277 	pr_err("List of directory entries:\n");
278 	ubifs_assert(!mutex_is_locked(&c->tnc_mutex));
279 
280 	lowest_dent_key(c, &key, inode->i_ino);
281 	while (1) {
282 		dent = ubifs_tnc_next_ent(c, &key, &nm);
283 		if (IS_ERR(dent)) {
284 			if (PTR_ERR(dent) != -ENOENT)
285 				pr_err("error %ld\n", PTR_ERR(dent));
286 			break;
287 		}
288 
289 		pr_err("\t%d: %s (%s)\n",
290 		       count++, dent->name, get_dent_type(dent->type));
291 
292 		nm.name = dent->name;
293 		nm.len = le16_to_cpu(dent->nlen);
294 		kfree(pdent);
295 		pdent = dent;
296 		key_read(c, &dent->key, &key);
297 	}
298 	kfree(pdent);
299 }
300 
301 void ubifs_dump_node(const struct ubifs_info *c, const void *node)
302 {
303 	int i, n;
304 	union ubifs_key key;
305 	const struct ubifs_ch *ch = node;
306 	char key_buf[DBG_KEY_BUF_LEN];
307 
308 	/* If the magic is incorrect, just hexdump the first bytes */
309 	if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) {
310 		pr_err("Not a node, first %zu bytes:", UBIFS_CH_SZ);
311 		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 32, 1,
312 			       (void *)node, UBIFS_CH_SZ, 1);
313 		return;
314 	}
315 
316 	spin_lock(&dbg_lock);
317 	dump_ch(node);
318 
319 	switch (ch->node_type) {
320 	case UBIFS_PAD_NODE:
321 	{
322 		const struct ubifs_pad_node *pad = node;
323 
324 		pr_err("\tpad_len        %u\n", le32_to_cpu(pad->pad_len));
325 		break;
326 	}
327 	case UBIFS_SB_NODE:
328 	{
329 		const struct ubifs_sb_node *sup = node;
330 		unsigned int sup_flags = le32_to_cpu(sup->flags);
331 
332 		pr_err("\tkey_hash       %d (%s)\n",
333 		       (int)sup->key_hash, get_key_hash(sup->key_hash));
334 		pr_err("\tkey_fmt        %d (%s)\n",
335 		       (int)sup->key_fmt, get_key_fmt(sup->key_fmt));
336 		pr_err("\tflags          %#x\n", sup_flags);
337 		pr_err("\tbig_lpt        %u\n",
338 		       !!(sup_flags & UBIFS_FLG_BIGLPT));
339 		pr_err("\tspace_fixup    %u\n",
340 		       !!(sup_flags & UBIFS_FLG_SPACE_FIXUP));
341 		pr_err("\tmin_io_size    %u\n", le32_to_cpu(sup->min_io_size));
342 		pr_err("\tleb_size       %u\n", le32_to_cpu(sup->leb_size));
343 		pr_err("\tleb_cnt        %u\n", le32_to_cpu(sup->leb_cnt));
344 		pr_err("\tmax_leb_cnt    %u\n", le32_to_cpu(sup->max_leb_cnt));
345 		pr_err("\tmax_bud_bytes  %llu\n",
346 		       (unsigned long long)le64_to_cpu(sup->max_bud_bytes));
347 		pr_err("\tlog_lebs       %u\n", le32_to_cpu(sup->log_lebs));
348 		pr_err("\tlpt_lebs       %u\n", le32_to_cpu(sup->lpt_lebs));
349 		pr_err("\torph_lebs      %u\n", le32_to_cpu(sup->orph_lebs));
350 		pr_err("\tjhead_cnt      %u\n", le32_to_cpu(sup->jhead_cnt));
351 		pr_err("\tfanout         %u\n", le32_to_cpu(sup->fanout));
352 		pr_err("\tlsave_cnt      %u\n", le32_to_cpu(sup->lsave_cnt));
353 		pr_err("\tdefault_compr  %u\n",
354 		       (int)le16_to_cpu(sup->default_compr));
355 		pr_err("\trp_size        %llu\n",
356 		       (unsigned long long)le64_to_cpu(sup->rp_size));
357 		pr_err("\trp_uid         %u\n", le32_to_cpu(sup->rp_uid));
358 		pr_err("\trp_gid         %u\n", le32_to_cpu(sup->rp_gid));
359 		pr_err("\tfmt_version    %u\n", le32_to_cpu(sup->fmt_version));
360 		pr_err("\ttime_gran      %u\n", le32_to_cpu(sup->time_gran));
361 		pr_err("\tUUID           %pUB\n", sup->uuid);
362 		break;
363 	}
364 	case UBIFS_MST_NODE:
365 	{
366 		const struct ubifs_mst_node *mst = node;
367 
368 		pr_err("\thighest_inum   %llu\n",
369 		       (unsigned long long)le64_to_cpu(mst->highest_inum));
370 		pr_err("\tcommit number  %llu\n",
371 		       (unsigned long long)le64_to_cpu(mst->cmt_no));
372 		pr_err("\tflags          %#x\n", le32_to_cpu(mst->flags));
373 		pr_err("\tlog_lnum       %u\n", le32_to_cpu(mst->log_lnum));
374 		pr_err("\troot_lnum      %u\n", le32_to_cpu(mst->root_lnum));
375 		pr_err("\troot_offs      %u\n", le32_to_cpu(mst->root_offs));
376 		pr_err("\troot_len       %u\n", le32_to_cpu(mst->root_len));
377 		pr_err("\tgc_lnum        %u\n", le32_to_cpu(mst->gc_lnum));
378 		pr_err("\tihead_lnum     %u\n", le32_to_cpu(mst->ihead_lnum));
379 		pr_err("\tihead_offs     %u\n", le32_to_cpu(mst->ihead_offs));
380 		pr_err("\tindex_size     %llu\n",
381 		       (unsigned long long)le64_to_cpu(mst->index_size));
382 		pr_err("\tlpt_lnum       %u\n", le32_to_cpu(mst->lpt_lnum));
383 		pr_err("\tlpt_offs       %u\n", le32_to_cpu(mst->lpt_offs));
384 		pr_err("\tnhead_lnum     %u\n", le32_to_cpu(mst->nhead_lnum));
385 		pr_err("\tnhead_offs     %u\n", le32_to_cpu(mst->nhead_offs));
386 		pr_err("\tltab_lnum      %u\n", le32_to_cpu(mst->ltab_lnum));
387 		pr_err("\tltab_offs      %u\n", le32_to_cpu(mst->ltab_offs));
388 		pr_err("\tlsave_lnum     %u\n", le32_to_cpu(mst->lsave_lnum));
389 		pr_err("\tlsave_offs     %u\n", le32_to_cpu(mst->lsave_offs));
390 		pr_err("\tlscan_lnum     %u\n", le32_to_cpu(mst->lscan_lnum));
391 		pr_err("\tleb_cnt        %u\n", le32_to_cpu(mst->leb_cnt));
392 		pr_err("\tempty_lebs     %u\n", le32_to_cpu(mst->empty_lebs));
393 		pr_err("\tidx_lebs       %u\n", le32_to_cpu(mst->idx_lebs));
394 		pr_err("\ttotal_free     %llu\n",
395 		       (unsigned long long)le64_to_cpu(mst->total_free));
396 		pr_err("\ttotal_dirty    %llu\n",
397 		       (unsigned long long)le64_to_cpu(mst->total_dirty));
398 		pr_err("\ttotal_used     %llu\n",
399 		       (unsigned long long)le64_to_cpu(mst->total_used));
400 		pr_err("\ttotal_dead     %llu\n",
401 		       (unsigned long long)le64_to_cpu(mst->total_dead));
402 		pr_err("\ttotal_dark     %llu\n",
403 		       (unsigned long long)le64_to_cpu(mst->total_dark));
404 		break;
405 	}
406 	case UBIFS_REF_NODE:
407 	{
408 		const struct ubifs_ref_node *ref = node;
409 
410 		pr_err("\tlnum           %u\n", le32_to_cpu(ref->lnum));
411 		pr_err("\toffs           %u\n", le32_to_cpu(ref->offs));
412 		pr_err("\tjhead          %u\n", le32_to_cpu(ref->jhead));
413 		break;
414 	}
415 	case UBIFS_INO_NODE:
416 	{
417 		const struct ubifs_ino_node *ino = node;
418 
419 		key_read(c, &ino->key, &key);
420 		pr_err("\tkey            %s\n",
421 		       dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
422 		pr_err("\tcreat_sqnum    %llu\n",
423 		       (unsigned long long)le64_to_cpu(ino->creat_sqnum));
424 		pr_err("\tsize           %llu\n",
425 		       (unsigned long long)le64_to_cpu(ino->size));
426 		pr_err("\tnlink          %u\n", le32_to_cpu(ino->nlink));
427 		pr_err("\tatime          %lld.%u\n",
428 		       (long long)le64_to_cpu(ino->atime_sec),
429 		       le32_to_cpu(ino->atime_nsec));
430 		pr_err("\tmtime          %lld.%u\n",
431 		       (long long)le64_to_cpu(ino->mtime_sec),
432 		       le32_to_cpu(ino->mtime_nsec));
433 		pr_err("\tctime          %lld.%u\n",
434 		       (long long)le64_to_cpu(ino->ctime_sec),
435 		       le32_to_cpu(ino->ctime_nsec));
436 		pr_err("\tuid            %u\n", le32_to_cpu(ino->uid));
437 		pr_err("\tgid            %u\n", le32_to_cpu(ino->gid));
438 		pr_err("\tmode           %u\n", le32_to_cpu(ino->mode));
439 		pr_err("\tflags          %#x\n", le32_to_cpu(ino->flags));
440 		pr_err("\txattr_cnt      %u\n", le32_to_cpu(ino->xattr_cnt));
441 		pr_err("\txattr_size     %u\n", le32_to_cpu(ino->xattr_size));
442 		pr_err("\txattr_names    %u\n", le32_to_cpu(ino->xattr_names));
443 		pr_err("\tcompr_type     %#x\n",
444 		       (int)le16_to_cpu(ino->compr_type));
445 		pr_err("\tdata len       %u\n", le32_to_cpu(ino->data_len));
446 		break;
447 	}
448 	case UBIFS_DENT_NODE:
449 	case UBIFS_XENT_NODE:
450 	{
451 		const struct ubifs_dent_node *dent = node;
452 		int nlen = le16_to_cpu(dent->nlen);
453 
454 		key_read(c, &dent->key, &key);
455 		pr_err("\tkey            %s\n",
456 		       dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
457 		pr_err("\tinum           %llu\n",
458 		       (unsigned long long)le64_to_cpu(dent->inum));
459 		pr_err("\ttype           %d\n", (int)dent->type);
460 		pr_err("\tnlen           %d\n", nlen);
461 		pr_err("\tname           ");
462 
463 		if (nlen > UBIFS_MAX_NLEN)
464 			pr_err("(bad name length, not printing, bad or corrupted node)");
465 		else {
466 			for (i = 0; i < nlen && dent->name[i]; i++)
467 				pr_cont("%c", dent->name[i]);
468 		}
469 		pr_cont("\n");
470 
471 		break;
472 	}
473 	case UBIFS_DATA_NODE:
474 	{
475 		const struct ubifs_data_node *dn = node;
476 		int dlen = le32_to_cpu(ch->len) - UBIFS_DATA_NODE_SZ;
477 
478 		key_read(c, &dn->key, &key);
479 		pr_err("\tkey            %s\n",
480 		       dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
481 		pr_err("\tsize           %u\n", le32_to_cpu(dn->size));
482 		pr_err("\tcompr_typ      %d\n",
483 		       (int)le16_to_cpu(dn->compr_type));
484 		pr_err("\tdata size      %d\n", dlen);
485 		pr_err("\tdata:\n");
486 		print_hex_dump(KERN_ERR, "\t", DUMP_PREFIX_OFFSET, 32, 1,
487 			       (void *)&dn->data, dlen, 0);
488 		break;
489 	}
490 	case UBIFS_TRUN_NODE:
491 	{
492 		const struct ubifs_trun_node *trun = node;
493 
494 		pr_err("\tinum           %u\n", le32_to_cpu(trun->inum));
495 		pr_err("\told_size       %llu\n",
496 		       (unsigned long long)le64_to_cpu(trun->old_size));
497 		pr_err("\tnew_size       %llu\n",
498 		       (unsigned long long)le64_to_cpu(trun->new_size));
499 		break;
500 	}
501 	case UBIFS_IDX_NODE:
502 	{
503 		const struct ubifs_idx_node *idx = node;
504 
505 		n = le16_to_cpu(idx->child_cnt);
506 		pr_err("\tchild_cnt      %d\n", n);
507 		pr_err("\tlevel          %d\n", (int)le16_to_cpu(idx->level));
508 		pr_err("\tBranches:\n");
509 
510 		for (i = 0; i < n && i < c->fanout - 1; i++) {
511 			const struct ubifs_branch *br;
512 
513 			br = ubifs_idx_branch(c, idx, i);
514 			key_read(c, &br->key, &key);
515 			pr_err("\t%d: LEB %d:%d len %d key %s\n",
516 			       i, le32_to_cpu(br->lnum), le32_to_cpu(br->offs),
517 			       le32_to_cpu(br->len),
518 			       dbg_snprintf_key(c, &key, key_buf,
519 						DBG_KEY_BUF_LEN));
520 		}
521 		break;
522 	}
523 	case UBIFS_CS_NODE:
524 		break;
525 	case UBIFS_ORPH_NODE:
526 	{
527 		const struct ubifs_orph_node *orph = node;
528 
529 		pr_err("\tcommit number  %llu\n",
530 		       (unsigned long long)
531 				le64_to_cpu(orph->cmt_no) & LLONG_MAX);
532 		pr_err("\tlast node flag %llu\n",
533 		       (unsigned long long)(le64_to_cpu(orph->cmt_no)) >> 63);
534 		n = (le32_to_cpu(ch->len) - UBIFS_ORPH_NODE_SZ) >> 3;
535 		pr_err("\t%d orphan inode numbers:\n", n);
536 		for (i = 0; i < n; i++)
537 			pr_err("\t  ino %llu\n",
538 			       (unsigned long long)le64_to_cpu(orph->inos[i]));
539 		break;
540 	}
541 	default:
542 		pr_err("node type %d was not recognized\n",
543 		       (int)ch->node_type);
544 	}
545 	spin_unlock(&dbg_lock);
546 }
547 
548 void ubifs_dump_budget_req(const struct ubifs_budget_req *req)
549 {
550 	spin_lock(&dbg_lock);
551 	pr_err("Budgeting request: new_ino %d, dirtied_ino %d\n",
552 	       req->new_ino, req->dirtied_ino);
553 	pr_err("\tnew_ino_d   %d, dirtied_ino_d %d\n",
554 	       req->new_ino_d, req->dirtied_ino_d);
555 	pr_err("\tnew_page    %d, dirtied_page %d\n",
556 	       req->new_page, req->dirtied_page);
557 	pr_err("\tnew_dent    %d, mod_dent     %d\n",
558 	       req->new_dent, req->mod_dent);
559 	pr_err("\tidx_growth  %d\n", req->idx_growth);
560 	pr_err("\tdata_growth %d dd_growth     %d\n",
561 	       req->data_growth, req->dd_growth);
562 	spin_unlock(&dbg_lock);
563 }
564 
565 void ubifs_dump_lstats(const struct ubifs_lp_stats *lst)
566 {
567 	spin_lock(&dbg_lock);
568 	pr_err("(pid %d) Lprops statistics: empty_lebs %d, idx_lebs  %d\n",
569 	       current->pid, lst->empty_lebs, lst->idx_lebs);
570 	pr_err("\ttaken_empty_lebs %d, total_free %lld, total_dirty %lld\n",
571 	       lst->taken_empty_lebs, lst->total_free, lst->total_dirty);
572 	pr_err("\ttotal_used %lld, total_dark %lld, total_dead %lld\n",
573 	       lst->total_used, lst->total_dark, lst->total_dead);
574 	spin_unlock(&dbg_lock);
575 }
576 
577 void ubifs_dump_budg(struct ubifs_info *c, const struct ubifs_budg_info *bi)
578 {
579 	int i;
580 	struct rb_node *rb;
581 	struct ubifs_bud *bud;
582 	struct ubifs_gced_idx_leb *idx_gc;
583 	long long available, outstanding, free;
584 
585 	spin_lock(&c->space_lock);
586 	spin_lock(&dbg_lock);
587 	pr_err("(pid %d) Budgeting info: data budget sum %lld, total budget sum %lld\n",
588 	       current->pid, bi->data_growth + bi->dd_growth,
589 	       bi->data_growth + bi->dd_growth + bi->idx_growth);
590 	pr_err("\tbudg_data_growth %lld, budg_dd_growth %lld, budg_idx_growth %lld\n",
591 	       bi->data_growth, bi->dd_growth, bi->idx_growth);
592 	pr_err("\tmin_idx_lebs %d, old_idx_sz %llu, uncommitted_idx %lld\n",
593 	       bi->min_idx_lebs, bi->old_idx_sz, bi->uncommitted_idx);
594 	pr_err("\tpage_budget %d, inode_budget %d, dent_budget %d\n",
595 	       bi->page_budget, bi->inode_budget, bi->dent_budget);
596 	pr_err("\tnospace %u, nospace_rp %u\n", bi->nospace, bi->nospace_rp);
597 	pr_err("\tdark_wm %d, dead_wm %d, max_idx_node_sz %d\n",
598 	       c->dark_wm, c->dead_wm, c->max_idx_node_sz);
599 
600 	if (bi != &c->bi)
601 		/*
602 		 * If we are dumping saved budgeting data, do not print
603 		 * additional information which is about the current state, not
604 		 * the old one which corresponded to the saved budgeting data.
605 		 */
606 		goto out_unlock;
607 
608 	pr_err("\tfreeable_cnt %d, calc_idx_sz %lld, idx_gc_cnt %d\n",
609 	       c->freeable_cnt, c->calc_idx_sz, c->idx_gc_cnt);
610 	pr_err("\tdirty_pg_cnt %ld, dirty_zn_cnt %ld, clean_zn_cnt %ld\n",
611 	       atomic_long_read(&c->dirty_pg_cnt),
612 	       atomic_long_read(&c->dirty_zn_cnt),
613 	       atomic_long_read(&c->clean_zn_cnt));
614 	pr_err("\tgc_lnum %d, ihead_lnum %d\n", c->gc_lnum, c->ihead_lnum);
615 
616 	/* If we are in R/O mode, journal heads do not exist */
617 	if (c->jheads)
618 		for (i = 0; i < c->jhead_cnt; i++)
619 			pr_err("\tjhead %s\t LEB %d\n",
620 			       dbg_jhead(c->jheads[i].wbuf.jhead),
621 			       c->jheads[i].wbuf.lnum);
622 	for (rb = rb_first(&c->buds); rb; rb = rb_next(rb)) {
623 		bud = rb_entry(rb, struct ubifs_bud, rb);
624 		pr_err("\tbud LEB %d\n", bud->lnum);
625 	}
626 	list_for_each_entry(bud, &c->old_buds, list)
627 		pr_err("\told bud LEB %d\n", bud->lnum);
628 	list_for_each_entry(idx_gc, &c->idx_gc, list)
629 		pr_err("\tGC'ed idx LEB %d unmap %d\n",
630 		       idx_gc->lnum, idx_gc->unmap);
631 	pr_err("\tcommit state %d\n", c->cmt_state);
632 
633 	/* Print budgeting predictions */
634 	available = ubifs_calc_available(c, c->bi.min_idx_lebs);
635 	outstanding = c->bi.data_growth + c->bi.dd_growth;
636 	free = ubifs_get_free_space_nolock(c);
637 	pr_err("Budgeting predictions:\n");
638 	pr_err("\tavailable: %lld, outstanding %lld, free %lld\n",
639 	       available, outstanding, free);
640 out_unlock:
641 	spin_unlock(&dbg_lock);
642 	spin_unlock(&c->space_lock);
643 }
644 
645 void ubifs_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp)
646 {
647 	int i, spc, dark = 0, dead = 0;
648 	struct rb_node *rb;
649 	struct ubifs_bud *bud;
650 
651 	spc = lp->free + lp->dirty;
652 	if (spc < c->dead_wm)
653 		dead = spc;
654 	else
655 		dark = ubifs_calc_dark(c, spc);
656 
657 	if (lp->flags & LPROPS_INDEX)
658 		pr_err("LEB %-7d free %-8d dirty %-8d used %-8d free + dirty %-8d flags %#x (",
659 		       lp->lnum, lp->free, lp->dirty, c->leb_size - spc, spc,
660 		       lp->flags);
661 	else
662 		pr_err("LEB %-7d free %-8d dirty %-8d used %-8d free + dirty %-8d dark %-4d dead %-4d nodes fit %-3d flags %#-4x (",
663 		       lp->lnum, lp->free, lp->dirty, c->leb_size - spc, spc,
664 		       dark, dead, (int)(spc / UBIFS_MAX_NODE_SZ), lp->flags);
665 
666 	if (lp->flags & LPROPS_TAKEN) {
667 		if (lp->flags & LPROPS_INDEX)
668 			pr_cont("index, taken");
669 		else
670 			pr_cont("taken");
671 	} else {
672 		const char *s;
673 
674 		if (lp->flags & LPROPS_INDEX) {
675 			switch (lp->flags & LPROPS_CAT_MASK) {
676 			case LPROPS_DIRTY_IDX:
677 				s = "dirty index";
678 				break;
679 			case LPROPS_FRDI_IDX:
680 				s = "freeable index";
681 				break;
682 			default:
683 				s = "index";
684 			}
685 		} else {
686 			switch (lp->flags & LPROPS_CAT_MASK) {
687 			case LPROPS_UNCAT:
688 				s = "not categorized";
689 				break;
690 			case LPROPS_DIRTY:
691 				s = "dirty";
692 				break;
693 			case LPROPS_FREE:
694 				s = "free";
695 				break;
696 			case LPROPS_EMPTY:
697 				s = "empty";
698 				break;
699 			case LPROPS_FREEABLE:
700 				s = "freeable";
701 				break;
702 			default:
703 				s = NULL;
704 				break;
705 			}
706 		}
707 		pr_cont("%s", s);
708 	}
709 
710 	for (rb = rb_first((struct rb_root *)&c->buds); rb; rb = rb_next(rb)) {
711 		bud = rb_entry(rb, struct ubifs_bud, rb);
712 		if (bud->lnum == lp->lnum) {
713 			int head = 0;
714 			for (i = 0; i < c->jhead_cnt; i++) {
715 				/*
716 				 * Note, if we are in R/O mode or in the middle
717 				 * of mounting/re-mounting, the write-buffers do
718 				 * not exist.
719 				 */
720 				if (c->jheads &&
721 				    lp->lnum == c->jheads[i].wbuf.lnum) {
722 					pr_cont(", jhead %s", dbg_jhead(i));
723 					head = 1;
724 				}
725 			}
726 			if (!head)
727 				pr_cont(", bud of jhead %s",
728 				       dbg_jhead(bud->jhead));
729 		}
730 	}
731 	if (lp->lnum == c->gc_lnum)
732 		pr_cont(", GC LEB");
733 	pr_cont(")\n");
734 }
735 
736 void ubifs_dump_lprops(struct ubifs_info *c)
737 {
738 	int lnum, err;
739 	struct ubifs_lprops lp;
740 	struct ubifs_lp_stats lst;
741 
742 	pr_err("(pid %d) start dumping LEB properties\n", current->pid);
743 	ubifs_get_lp_stats(c, &lst);
744 	ubifs_dump_lstats(&lst);
745 
746 	for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) {
747 		err = ubifs_read_one_lp(c, lnum, &lp);
748 		if (err) {
749 			ubifs_err(c, "cannot read lprops for LEB %d", lnum);
750 			continue;
751 		}
752 
753 		ubifs_dump_lprop(c, &lp);
754 	}
755 	pr_err("(pid %d) finish dumping LEB properties\n", current->pid);
756 }
757 
758 void ubifs_dump_lpt_info(struct ubifs_info *c)
759 {
760 	int i;
761 
762 	spin_lock(&dbg_lock);
763 	pr_err("(pid %d) dumping LPT information\n", current->pid);
764 	pr_err("\tlpt_sz:        %lld\n", c->lpt_sz);
765 	pr_err("\tpnode_sz:      %d\n", c->pnode_sz);
766 	pr_err("\tnnode_sz:      %d\n", c->nnode_sz);
767 	pr_err("\tltab_sz:       %d\n", c->ltab_sz);
768 	pr_err("\tlsave_sz:      %d\n", c->lsave_sz);
769 	pr_err("\tbig_lpt:       %d\n", c->big_lpt);
770 	pr_err("\tlpt_hght:      %d\n", c->lpt_hght);
771 	pr_err("\tpnode_cnt:     %d\n", c->pnode_cnt);
772 	pr_err("\tnnode_cnt:     %d\n", c->nnode_cnt);
773 	pr_err("\tdirty_pn_cnt:  %d\n", c->dirty_pn_cnt);
774 	pr_err("\tdirty_nn_cnt:  %d\n", c->dirty_nn_cnt);
775 	pr_err("\tlsave_cnt:     %d\n", c->lsave_cnt);
776 	pr_err("\tspace_bits:    %d\n", c->space_bits);
777 	pr_err("\tlpt_lnum_bits: %d\n", c->lpt_lnum_bits);
778 	pr_err("\tlpt_offs_bits: %d\n", c->lpt_offs_bits);
779 	pr_err("\tlpt_spc_bits:  %d\n", c->lpt_spc_bits);
780 	pr_err("\tpcnt_bits:     %d\n", c->pcnt_bits);
781 	pr_err("\tlnum_bits:     %d\n", c->lnum_bits);
782 	pr_err("\tLPT root is at %d:%d\n", c->lpt_lnum, c->lpt_offs);
783 	pr_err("\tLPT head is at %d:%d\n",
784 	       c->nhead_lnum, c->nhead_offs);
785 	pr_err("\tLPT ltab is at %d:%d\n", c->ltab_lnum, c->ltab_offs);
786 	if (c->big_lpt)
787 		pr_err("\tLPT lsave is at %d:%d\n",
788 		       c->lsave_lnum, c->lsave_offs);
789 	for (i = 0; i < c->lpt_lebs; i++)
790 		pr_err("\tLPT LEB %d free %d dirty %d tgc %d cmt %d\n",
791 		       i + c->lpt_first, c->ltab[i].free, c->ltab[i].dirty,
792 		       c->ltab[i].tgc, c->ltab[i].cmt);
793 	spin_unlock(&dbg_lock);
794 }
795 
796 void ubifs_dump_sleb(const struct ubifs_info *c,
797 		     const struct ubifs_scan_leb *sleb, int offs)
798 {
799 	struct ubifs_scan_node *snod;
800 
801 	pr_err("(pid %d) start dumping scanned data from LEB %d:%d\n",
802 	       current->pid, sleb->lnum, offs);
803 
804 	list_for_each_entry(snod, &sleb->nodes, list) {
805 		cond_resched();
806 		pr_err("Dumping node at LEB %d:%d len %d\n",
807 		       sleb->lnum, snod->offs, snod->len);
808 		ubifs_dump_node(c, snod->node);
809 	}
810 }
811 
812 void ubifs_dump_leb(const struct ubifs_info *c, int lnum)
813 {
814 	struct ubifs_scan_leb *sleb;
815 	struct ubifs_scan_node *snod;
816 	void *buf;
817 
818 	pr_err("(pid %d) start dumping LEB %d\n", current->pid, lnum);
819 
820 	buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
821 	if (!buf) {
822 		ubifs_err(c, "cannot allocate memory for dumping LEB %d", lnum);
823 		return;
824 	}
825 
826 	sleb = ubifs_scan(c, lnum, 0, buf, 0);
827 	if (IS_ERR(sleb)) {
828 		ubifs_err(c, "scan error %d", (int)PTR_ERR(sleb));
829 		goto out;
830 	}
831 
832 	pr_err("LEB %d has %d nodes ending at %d\n", lnum,
833 	       sleb->nodes_cnt, sleb->endpt);
834 
835 	list_for_each_entry(snod, &sleb->nodes, list) {
836 		cond_resched();
837 		pr_err("Dumping node at LEB %d:%d len %d\n", lnum,
838 		       snod->offs, snod->len);
839 		ubifs_dump_node(c, snod->node);
840 	}
841 
842 	pr_err("(pid %d) finish dumping LEB %d\n", current->pid, lnum);
843 	ubifs_scan_destroy(sleb);
844 
845 out:
846 	vfree(buf);
847 	return;
848 }
849 
850 void ubifs_dump_znode(const struct ubifs_info *c,
851 		      const struct ubifs_znode *znode)
852 {
853 	int n;
854 	const struct ubifs_zbranch *zbr;
855 	char key_buf[DBG_KEY_BUF_LEN];
856 
857 	spin_lock(&dbg_lock);
858 	if (znode->parent)
859 		zbr = &znode->parent->zbranch[znode->iip];
860 	else
861 		zbr = &c->zroot;
862 
863 	pr_err("znode %p, LEB %d:%d len %d parent %p iip %d level %d child_cnt %d flags %lx\n",
864 	       znode, zbr->lnum, zbr->offs, zbr->len, znode->parent, znode->iip,
865 	       znode->level, znode->child_cnt, znode->flags);
866 
867 	if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
868 		spin_unlock(&dbg_lock);
869 		return;
870 	}
871 
872 	pr_err("zbranches:\n");
873 	for (n = 0; n < znode->child_cnt; n++) {
874 		zbr = &znode->zbranch[n];
875 		if (znode->level > 0)
876 			pr_err("\t%d: znode %p LEB %d:%d len %d key %s\n",
877 			       n, zbr->znode, zbr->lnum, zbr->offs, zbr->len,
878 			       dbg_snprintf_key(c, &zbr->key, key_buf,
879 						DBG_KEY_BUF_LEN));
880 		else
881 			pr_err("\t%d: LNC %p LEB %d:%d len %d key %s\n",
882 			       n, zbr->znode, zbr->lnum, zbr->offs, zbr->len,
883 			       dbg_snprintf_key(c, &zbr->key, key_buf,
884 						DBG_KEY_BUF_LEN));
885 	}
886 	spin_unlock(&dbg_lock);
887 }
888 
889 void ubifs_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
890 {
891 	int i;
892 
893 	pr_err("(pid %d) start dumping heap cat %d (%d elements)\n",
894 	       current->pid, cat, heap->cnt);
895 	for (i = 0; i < heap->cnt; i++) {
896 		struct ubifs_lprops *lprops = heap->arr[i];
897 
898 		pr_err("\t%d. LEB %d hpos %d free %d dirty %d flags %d\n",
899 		       i, lprops->lnum, lprops->hpos, lprops->free,
900 		       lprops->dirty, lprops->flags);
901 	}
902 	pr_err("(pid %d) finish dumping heap\n", current->pid);
903 }
904 
905 void ubifs_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
906 		      struct ubifs_nnode *parent, int iip)
907 {
908 	int i;
909 
910 	pr_err("(pid %d) dumping pnode:\n", current->pid);
911 	pr_err("\taddress %zx parent %zx cnext %zx\n",
912 	       (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
913 	pr_err("\tflags %lu iip %d level %d num %d\n",
914 	       pnode->flags, iip, pnode->level, pnode->num);
915 	for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
916 		struct ubifs_lprops *lp = &pnode->lprops[i];
917 
918 		pr_err("\t%d: free %d dirty %d flags %d lnum %d\n",
919 		       i, lp->free, lp->dirty, lp->flags, lp->lnum);
920 	}
921 }
922 
923 void ubifs_dump_tnc(struct ubifs_info *c)
924 {
925 	struct ubifs_znode *znode;
926 	int level;
927 
928 	pr_err("\n");
929 	pr_err("(pid %d) start dumping TNC tree\n", current->pid);
930 	znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
931 	level = znode->level;
932 	pr_err("== Level %d ==\n", level);
933 	while (znode) {
934 		if (level != znode->level) {
935 			level = znode->level;
936 			pr_err("== Level %d ==\n", level);
937 		}
938 		ubifs_dump_znode(c, znode);
939 		znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
940 	}
941 	pr_err("(pid %d) finish dumping TNC tree\n", current->pid);
942 }
943 
944 static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
945 		      void *priv)
946 {
947 	ubifs_dump_znode(c, znode);
948 	return 0;
949 }
950 
951 /**
952  * ubifs_dump_index - dump the on-flash index.
953  * @c: UBIFS file-system description object
954  *
955  * This function dumps whole UBIFS indexing B-tree, unlike 'ubifs_dump_tnc()'
956  * which dumps only in-memory znodes and does not read znodes which from flash.
957  */
958 void ubifs_dump_index(struct ubifs_info *c)
959 {
960 	dbg_walk_index(c, NULL, dump_znode, NULL);
961 }
962 
963 /**
964  * dbg_save_space_info - save information about flash space.
965  * @c: UBIFS file-system description object
966  *
967  * This function saves information about UBIFS free space, dirty space, etc, in
968  * order to check it later.
969  */
970 void dbg_save_space_info(struct ubifs_info *c)
971 {
972 	struct ubifs_debug_info *d = c->dbg;
973 	int freeable_cnt;
974 
975 	spin_lock(&c->space_lock);
976 	memcpy(&d->saved_lst, &c->lst, sizeof(struct ubifs_lp_stats));
977 	memcpy(&d->saved_bi, &c->bi, sizeof(struct ubifs_budg_info));
978 	d->saved_idx_gc_cnt = c->idx_gc_cnt;
979 
980 	/*
981 	 * We use a dirty hack here and zero out @c->freeable_cnt, because it
982 	 * affects the free space calculations, and UBIFS might not know about
983 	 * all freeable eraseblocks. Indeed, we know about freeable eraseblocks
984 	 * only when we read their lprops, and we do this only lazily, upon the
985 	 * need. So at any given point of time @c->freeable_cnt might be not
986 	 * exactly accurate.
987 	 *
988 	 * Just one example about the issue we hit when we did not zero
989 	 * @c->freeable_cnt.
990 	 * 1. The file-system is mounted R/O, c->freeable_cnt is %0. We save the
991 	 *    amount of free space in @d->saved_free
992 	 * 2. We re-mount R/W, which makes UBIFS to read the "lsave"
993 	 *    information from flash, where we cache LEBs from various
994 	 *    categories ('ubifs_remount_fs()' -> 'ubifs_lpt_init()'
995 	 *    -> 'lpt_init_wr()' -> 'read_lsave()' -> 'ubifs_lpt_lookup()'
996 	 *    -> 'ubifs_get_pnode()' -> 'update_cats()'
997 	 *    -> 'ubifs_add_to_cat()').
998 	 * 3. Lsave contains a freeable eraseblock, and @c->freeable_cnt
999 	 *    becomes %1.
1000 	 * 4. We calculate the amount of free space when the re-mount is
1001 	 *    finished in 'dbg_check_space_info()' and it does not match
1002 	 *    @d->saved_free.
1003 	 */
1004 	freeable_cnt = c->freeable_cnt;
1005 	c->freeable_cnt = 0;
1006 	d->saved_free = ubifs_get_free_space_nolock(c);
1007 	c->freeable_cnt = freeable_cnt;
1008 	spin_unlock(&c->space_lock);
1009 }
1010 
1011 /**
1012  * dbg_check_space_info - check flash space information.
1013  * @c: UBIFS file-system description object
1014  *
1015  * This function compares current flash space information with the information
1016  * which was saved when the 'dbg_save_space_info()' function was called.
1017  * Returns zero if the information has not changed, and %-EINVAL it it has
1018  * changed.
1019  */
1020 int dbg_check_space_info(struct ubifs_info *c)
1021 {
1022 	struct ubifs_debug_info *d = c->dbg;
1023 	struct ubifs_lp_stats lst;
1024 	long long free;
1025 	int freeable_cnt;
1026 
1027 	spin_lock(&c->space_lock);
1028 	freeable_cnt = c->freeable_cnt;
1029 	c->freeable_cnt = 0;
1030 	free = ubifs_get_free_space_nolock(c);
1031 	c->freeable_cnt = freeable_cnt;
1032 	spin_unlock(&c->space_lock);
1033 
1034 	if (free != d->saved_free) {
1035 		ubifs_err(c, "free space changed from %lld to %lld",
1036 			  d->saved_free, free);
1037 		goto out;
1038 	}
1039 
1040 	return 0;
1041 
1042 out:
1043 	ubifs_msg(c, "saved lprops statistics dump");
1044 	ubifs_dump_lstats(&d->saved_lst);
1045 	ubifs_msg(c, "saved budgeting info dump");
1046 	ubifs_dump_budg(c, &d->saved_bi);
1047 	ubifs_msg(c, "saved idx_gc_cnt %d", d->saved_idx_gc_cnt);
1048 	ubifs_msg(c, "current lprops statistics dump");
1049 	ubifs_get_lp_stats(c, &lst);
1050 	ubifs_dump_lstats(&lst);
1051 	ubifs_msg(c, "current budgeting info dump");
1052 	ubifs_dump_budg(c, &c->bi);
1053 	dump_stack();
1054 	return -EINVAL;
1055 }
1056 
1057 /**
1058  * dbg_check_synced_i_size - check synchronized inode size.
1059  * @c: UBIFS file-system description object
1060  * @inode: inode to check
1061  *
1062  * If inode is clean, synchronized inode size has to be equivalent to current
1063  * inode size. This function has to be called only for locked inodes (@i_mutex
1064  * has to be locked). Returns %0 if synchronized inode size if correct, and
1065  * %-EINVAL if not.
1066  */
1067 int dbg_check_synced_i_size(const struct ubifs_info *c, struct inode *inode)
1068 {
1069 	int err = 0;
1070 	struct ubifs_inode *ui = ubifs_inode(inode);
1071 
1072 	if (!dbg_is_chk_gen(c))
1073 		return 0;
1074 	if (!S_ISREG(inode->i_mode))
1075 		return 0;
1076 
1077 	mutex_lock(&ui->ui_mutex);
1078 	spin_lock(&ui->ui_lock);
1079 	if (ui->ui_size != ui->synced_i_size && !ui->dirty) {
1080 		ubifs_err(c, "ui_size is %lld, synced_i_size is %lld, but inode is clean",
1081 			  ui->ui_size, ui->synced_i_size);
1082 		ubifs_err(c, "i_ino %lu, i_mode %#x, i_size %lld", inode->i_ino,
1083 			  inode->i_mode, i_size_read(inode));
1084 		dump_stack();
1085 		err = -EINVAL;
1086 	}
1087 	spin_unlock(&ui->ui_lock);
1088 	mutex_unlock(&ui->ui_mutex);
1089 	return err;
1090 }
1091 
1092 /*
1093  * dbg_check_dir - check directory inode size and link count.
1094  * @c: UBIFS file-system description object
1095  * @dir: the directory to calculate size for
1096  * @size: the result is returned here
1097  *
1098  * This function makes sure that directory size and link count are correct.
1099  * Returns zero in case of success and a negative error code in case of
1100  * failure.
1101  *
1102  * Note, it is good idea to make sure the @dir->i_mutex is locked before
1103  * calling this function.
1104  */
1105 int dbg_check_dir(struct ubifs_info *c, const struct inode *dir)
1106 {
1107 	unsigned int nlink = 2;
1108 	union ubifs_key key;
1109 	struct ubifs_dent_node *dent, *pdent = NULL;
1110 	struct qstr nm = { .name = NULL };
1111 	loff_t size = UBIFS_INO_NODE_SZ;
1112 
1113 	if (!dbg_is_chk_gen(c))
1114 		return 0;
1115 
1116 	if (!S_ISDIR(dir->i_mode))
1117 		return 0;
1118 
1119 	lowest_dent_key(c, &key, dir->i_ino);
1120 	while (1) {
1121 		int err;
1122 
1123 		dent = ubifs_tnc_next_ent(c, &key, &nm);
1124 		if (IS_ERR(dent)) {
1125 			err = PTR_ERR(dent);
1126 			if (err == -ENOENT)
1127 				break;
1128 			return err;
1129 		}
1130 
1131 		nm.name = dent->name;
1132 		nm.len = le16_to_cpu(dent->nlen);
1133 		size += CALC_DENT_SIZE(nm.len);
1134 		if (dent->type == UBIFS_ITYPE_DIR)
1135 			nlink += 1;
1136 		kfree(pdent);
1137 		pdent = dent;
1138 		key_read(c, &dent->key, &key);
1139 	}
1140 	kfree(pdent);
1141 
1142 	if (i_size_read(dir) != size) {
1143 		ubifs_err(c, "directory inode %lu has size %llu, but calculated size is %llu",
1144 			  dir->i_ino, (unsigned long long)i_size_read(dir),
1145 			  (unsigned long long)size);
1146 		ubifs_dump_inode(c, dir);
1147 		dump_stack();
1148 		return -EINVAL;
1149 	}
1150 	if (dir->i_nlink != nlink) {
1151 		ubifs_err(c, "directory inode %lu has nlink %u, but calculated nlink is %u",
1152 			  dir->i_ino, dir->i_nlink, nlink);
1153 		ubifs_dump_inode(c, dir);
1154 		dump_stack();
1155 		return -EINVAL;
1156 	}
1157 
1158 	return 0;
1159 }
1160 
1161 /**
1162  * dbg_check_key_order - make sure that colliding keys are properly ordered.
1163  * @c: UBIFS file-system description object
1164  * @zbr1: first zbranch
1165  * @zbr2: following zbranch
1166  *
1167  * In UBIFS indexing B-tree colliding keys has to be sorted in binary order of
1168  * names of the direntries/xentries which are referred by the keys. This
1169  * function reads direntries/xentries referred by @zbr1 and @zbr2 and makes
1170  * sure the name of direntry/xentry referred by @zbr1 is less than
1171  * direntry/xentry referred by @zbr2. Returns zero if this is true, %1 if not,
1172  * and a negative error code in case of failure.
1173  */
1174 static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
1175 			       struct ubifs_zbranch *zbr2)
1176 {
1177 	int err, nlen1, nlen2, cmp;
1178 	struct ubifs_dent_node *dent1, *dent2;
1179 	union ubifs_key key;
1180 	char key_buf[DBG_KEY_BUF_LEN];
1181 
1182 	ubifs_assert(!keys_cmp(c, &zbr1->key, &zbr2->key));
1183 	dent1 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
1184 	if (!dent1)
1185 		return -ENOMEM;
1186 	dent2 = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
1187 	if (!dent2) {
1188 		err = -ENOMEM;
1189 		goto out_free;
1190 	}
1191 
1192 	err = ubifs_tnc_read_node(c, zbr1, dent1);
1193 	if (err)
1194 		goto out_free;
1195 	err = ubifs_validate_entry(c, dent1);
1196 	if (err)
1197 		goto out_free;
1198 
1199 	err = ubifs_tnc_read_node(c, zbr2, dent2);
1200 	if (err)
1201 		goto out_free;
1202 	err = ubifs_validate_entry(c, dent2);
1203 	if (err)
1204 		goto out_free;
1205 
1206 	/* Make sure node keys are the same as in zbranch */
1207 	err = 1;
1208 	key_read(c, &dent1->key, &key);
1209 	if (keys_cmp(c, &zbr1->key, &key)) {
1210 		ubifs_err(c, "1st entry at %d:%d has key %s", zbr1->lnum,
1211 			  zbr1->offs, dbg_snprintf_key(c, &key, key_buf,
1212 						       DBG_KEY_BUF_LEN));
1213 		ubifs_err(c, "but it should have key %s according to tnc",
1214 			  dbg_snprintf_key(c, &zbr1->key, key_buf,
1215 					   DBG_KEY_BUF_LEN));
1216 		ubifs_dump_node(c, dent1);
1217 		goto out_free;
1218 	}
1219 
1220 	key_read(c, &dent2->key, &key);
1221 	if (keys_cmp(c, &zbr2->key, &key)) {
1222 		ubifs_err(c, "2nd entry at %d:%d has key %s", zbr1->lnum,
1223 			  zbr1->offs, dbg_snprintf_key(c, &key, key_buf,
1224 						       DBG_KEY_BUF_LEN));
1225 		ubifs_err(c, "but it should have key %s according to tnc",
1226 			  dbg_snprintf_key(c, &zbr2->key, key_buf,
1227 					   DBG_KEY_BUF_LEN));
1228 		ubifs_dump_node(c, dent2);
1229 		goto out_free;
1230 	}
1231 
1232 	nlen1 = le16_to_cpu(dent1->nlen);
1233 	nlen2 = le16_to_cpu(dent2->nlen);
1234 
1235 	cmp = memcmp(dent1->name, dent2->name, min_t(int, nlen1, nlen2));
1236 	if (cmp < 0 || (cmp == 0 && nlen1 < nlen2)) {
1237 		err = 0;
1238 		goto out_free;
1239 	}
1240 	if (cmp == 0 && nlen1 == nlen2)
1241 		ubifs_err(c, "2 xent/dent nodes with the same name");
1242 	else
1243 		ubifs_err(c, "bad order of colliding key %s",
1244 			  dbg_snprintf_key(c, &key, key_buf, DBG_KEY_BUF_LEN));
1245 
1246 	ubifs_msg(c, "first node at %d:%d\n", zbr1->lnum, zbr1->offs);
1247 	ubifs_dump_node(c, dent1);
1248 	ubifs_msg(c, "second node at %d:%d\n", zbr2->lnum, zbr2->offs);
1249 	ubifs_dump_node(c, dent2);
1250 
1251 out_free:
1252 	kfree(dent2);
1253 	kfree(dent1);
1254 	return err;
1255 }
1256 
1257 /**
1258  * dbg_check_znode - check if znode is all right.
1259  * @c: UBIFS file-system description object
1260  * @zbr: zbranch which points to this znode
1261  *
1262  * This function makes sure that znode referred to by @zbr is all right.
1263  * Returns zero if it is, and %-EINVAL if it is not.
1264  */
1265 static int dbg_check_znode(struct ubifs_info *c, struct ubifs_zbranch *zbr)
1266 {
1267 	struct ubifs_znode *znode = zbr->znode;
1268 	struct ubifs_znode *zp = znode->parent;
1269 	int n, err, cmp;
1270 
1271 	if (znode->child_cnt <= 0 || znode->child_cnt > c->fanout) {
1272 		err = 1;
1273 		goto out;
1274 	}
1275 	if (znode->level < 0) {
1276 		err = 2;
1277 		goto out;
1278 	}
1279 	if (znode->iip < 0 || znode->iip >= c->fanout) {
1280 		err = 3;
1281 		goto out;
1282 	}
1283 
1284 	if (zbr->len == 0)
1285 		/* Only dirty zbranch may have no on-flash nodes */
1286 		if (!ubifs_zn_dirty(znode)) {
1287 			err = 4;
1288 			goto out;
1289 		}
1290 
1291 	if (ubifs_zn_dirty(znode)) {
1292 		/*
1293 		 * If znode is dirty, its parent has to be dirty as well. The
1294 		 * order of the operation is important, so we have to have
1295 		 * memory barriers.
1296 		 */
1297 		smp_mb();
1298 		if (zp && !ubifs_zn_dirty(zp)) {
1299 			/*
1300 			 * The dirty flag is atomic and is cleared outside the
1301 			 * TNC mutex, so znode's dirty flag may now have
1302 			 * been cleared. The child is always cleared before the
1303 			 * parent, so we just need to check again.
1304 			 */
1305 			smp_mb();
1306 			if (ubifs_zn_dirty(znode)) {
1307 				err = 5;
1308 				goto out;
1309 			}
1310 		}
1311 	}
1312 
1313 	if (zp) {
1314 		const union ubifs_key *min, *max;
1315 
1316 		if (znode->level != zp->level - 1) {
1317 			err = 6;
1318 			goto out;
1319 		}
1320 
1321 		/* Make sure the 'parent' pointer in our znode is correct */
1322 		err = ubifs_search_zbranch(c, zp, &zbr->key, &n);
1323 		if (!err) {
1324 			/* This zbranch does not exist in the parent */
1325 			err = 7;
1326 			goto out;
1327 		}
1328 
1329 		if (znode->iip >= zp->child_cnt) {
1330 			err = 8;
1331 			goto out;
1332 		}
1333 
1334 		if (znode->iip != n) {
1335 			/* This may happen only in case of collisions */
1336 			if (keys_cmp(c, &zp->zbranch[n].key,
1337 				     &zp->zbranch[znode->iip].key)) {
1338 				err = 9;
1339 				goto out;
1340 			}
1341 			n = znode->iip;
1342 		}
1343 
1344 		/*
1345 		 * Make sure that the first key in our znode is greater than or
1346 		 * equal to the key in the pointing zbranch.
1347 		 */
1348 		min = &zbr->key;
1349 		cmp = keys_cmp(c, min, &znode->zbranch[0].key);
1350 		if (cmp == 1) {
1351 			err = 10;
1352 			goto out;
1353 		}
1354 
1355 		if (n + 1 < zp->child_cnt) {
1356 			max = &zp->zbranch[n + 1].key;
1357 
1358 			/*
1359 			 * Make sure the last key in our znode is less or
1360 			 * equivalent than the key in the zbranch which goes
1361 			 * after our pointing zbranch.
1362 			 */
1363 			cmp = keys_cmp(c, max,
1364 				&znode->zbranch[znode->child_cnt - 1].key);
1365 			if (cmp == -1) {
1366 				err = 11;
1367 				goto out;
1368 			}
1369 		}
1370 	} else {
1371 		/* This may only be root znode */
1372 		if (zbr != &c->zroot) {
1373 			err = 12;
1374 			goto out;
1375 		}
1376 	}
1377 
1378 	/*
1379 	 * Make sure that next key is greater or equivalent then the previous
1380 	 * one.
1381 	 */
1382 	for (n = 1; n < znode->child_cnt; n++) {
1383 		cmp = keys_cmp(c, &znode->zbranch[n - 1].key,
1384 			       &znode->zbranch[n].key);
1385 		if (cmp > 0) {
1386 			err = 13;
1387 			goto out;
1388 		}
1389 		if (cmp == 0) {
1390 			/* This can only be keys with colliding hash */
1391 			if (!is_hash_key(c, &znode->zbranch[n].key)) {
1392 				err = 14;
1393 				goto out;
1394 			}
1395 
1396 			if (znode->level != 0 || c->replaying)
1397 				continue;
1398 
1399 			/*
1400 			 * Colliding keys should follow binary order of
1401 			 * corresponding xentry/dentry names.
1402 			 */
1403 			err = dbg_check_key_order(c, &znode->zbranch[n - 1],
1404 						  &znode->zbranch[n]);
1405 			if (err < 0)
1406 				return err;
1407 			if (err) {
1408 				err = 15;
1409 				goto out;
1410 			}
1411 		}
1412 	}
1413 
1414 	for (n = 0; n < znode->child_cnt; n++) {
1415 		if (!znode->zbranch[n].znode &&
1416 		    (znode->zbranch[n].lnum == 0 ||
1417 		     znode->zbranch[n].len == 0)) {
1418 			err = 16;
1419 			goto out;
1420 		}
1421 
1422 		if (znode->zbranch[n].lnum != 0 &&
1423 		    znode->zbranch[n].len == 0) {
1424 			err = 17;
1425 			goto out;
1426 		}
1427 
1428 		if (znode->zbranch[n].lnum == 0 &&
1429 		    znode->zbranch[n].len != 0) {
1430 			err = 18;
1431 			goto out;
1432 		}
1433 
1434 		if (znode->zbranch[n].lnum == 0 &&
1435 		    znode->zbranch[n].offs != 0) {
1436 			err = 19;
1437 			goto out;
1438 		}
1439 
1440 		if (znode->level != 0 && znode->zbranch[n].znode)
1441 			if (znode->zbranch[n].znode->parent != znode) {
1442 				err = 20;
1443 				goto out;
1444 			}
1445 	}
1446 
1447 	return 0;
1448 
1449 out:
1450 	ubifs_err(c, "failed, error %d", err);
1451 	ubifs_msg(c, "dump of the znode");
1452 	ubifs_dump_znode(c, znode);
1453 	if (zp) {
1454 		ubifs_msg(c, "dump of the parent znode");
1455 		ubifs_dump_znode(c, zp);
1456 	}
1457 	dump_stack();
1458 	return -EINVAL;
1459 }
1460 
1461 /**
1462  * dbg_check_tnc - check TNC tree.
1463  * @c: UBIFS file-system description object
1464  * @extra: do extra checks that are possible at start commit
1465  *
1466  * This function traverses whole TNC tree and checks every znode. Returns zero
1467  * if everything is all right and %-EINVAL if something is wrong with TNC.
1468  */
1469 int dbg_check_tnc(struct ubifs_info *c, int extra)
1470 {
1471 	struct ubifs_znode *znode;
1472 	long clean_cnt = 0, dirty_cnt = 0;
1473 	int err, last;
1474 
1475 	if (!dbg_is_chk_index(c))
1476 		return 0;
1477 
1478 	ubifs_assert(mutex_is_locked(&c->tnc_mutex));
1479 	if (!c->zroot.znode)
1480 		return 0;
1481 
1482 	znode = ubifs_tnc_postorder_first(c->zroot.znode);
1483 	while (1) {
1484 		struct ubifs_znode *prev;
1485 		struct ubifs_zbranch *zbr;
1486 
1487 		if (!znode->parent)
1488 			zbr = &c->zroot;
1489 		else
1490 			zbr = &znode->parent->zbranch[znode->iip];
1491 
1492 		err = dbg_check_znode(c, zbr);
1493 		if (err)
1494 			return err;
1495 
1496 		if (extra) {
1497 			if (ubifs_zn_dirty(znode))
1498 				dirty_cnt += 1;
1499 			else
1500 				clean_cnt += 1;
1501 		}
1502 
1503 		prev = znode;
1504 		znode = ubifs_tnc_postorder_next(znode);
1505 		if (!znode)
1506 			break;
1507 
1508 		/*
1509 		 * If the last key of this znode is equivalent to the first key
1510 		 * of the next znode (collision), then check order of the keys.
1511 		 */
1512 		last = prev->child_cnt - 1;
1513 		if (prev->level == 0 && znode->level == 0 && !c->replaying &&
1514 		    !keys_cmp(c, &prev->zbranch[last].key,
1515 			      &znode->zbranch[0].key)) {
1516 			err = dbg_check_key_order(c, &prev->zbranch[last],
1517 						  &znode->zbranch[0]);
1518 			if (err < 0)
1519 				return err;
1520 			if (err) {
1521 				ubifs_msg(c, "first znode");
1522 				ubifs_dump_znode(c, prev);
1523 				ubifs_msg(c, "second znode");
1524 				ubifs_dump_znode(c, znode);
1525 				return -EINVAL;
1526 			}
1527 		}
1528 	}
1529 
1530 	if (extra) {
1531 		if (clean_cnt != atomic_long_read(&c->clean_zn_cnt)) {
1532 			ubifs_err(c, "incorrect clean_zn_cnt %ld, calculated %ld",
1533 				  atomic_long_read(&c->clean_zn_cnt),
1534 				  clean_cnt);
1535 			return -EINVAL;
1536 		}
1537 		if (dirty_cnt != atomic_long_read(&c->dirty_zn_cnt)) {
1538 			ubifs_err(c, "incorrect dirty_zn_cnt %ld, calculated %ld",
1539 				  atomic_long_read(&c->dirty_zn_cnt),
1540 				  dirty_cnt);
1541 			return -EINVAL;
1542 		}
1543 	}
1544 
1545 	return 0;
1546 }
1547 
1548 /**
1549  * dbg_walk_index - walk the on-flash index.
1550  * @c: UBIFS file-system description object
1551  * @leaf_cb: called for each leaf node
1552  * @znode_cb: called for each indexing node
1553  * @priv: private data which is passed to callbacks
1554  *
1555  * This function walks the UBIFS index and calls the @leaf_cb for each leaf
1556  * node and @znode_cb for each indexing node. Returns zero in case of success
1557  * and a negative error code in case of failure.
1558  *
1559  * It would be better if this function removed every znode it pulled to into
1560  * the TNC, so that the behavior more closely matched the non-debugging
1561  * behavior.
1562  */
1563 int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
1564 		   dbg_znode_callback znode_cb, void *priv)
1565 {
1566 	int err;
1567 	struct ubifs_zbranch *zbr;
1568 	struct ubifs_znode *znode, *child;
1569 
1570 	mutex_lock(&c->tnc_mutex);
1571 	/* If the root indexing node is not in TNC - pull it */
1572 	if (!c->zroot.znode) {
1573 		c->zroot.znode = ubifs_load_znode(c, &c->zroot, NULL, 0);
1574 		if (IS_ERR(c->zroot.znode)) {
1575 			err = PTR_ERR(c->zroot.znode);
1576 			c->zroot.znode = NULL;
1577 			goto out_unlock;
1578 		}
1579 	}
1580 
1581 	/*
1582 	 * We are going to traverse the indexing tree in the postorder manner.
1583 	 * Go down and find the leftmost indexing node where we are going to
1584 	 * start from.
1585 	 */
1586 	znode = c->zroot.znode;
1587 	while (znode->level > 0) {
1588 		zbr = &znode->zbranch[0];
1589 		child = zbr->znode;
1590 		if (!child) {
1591 			child = ubifs_load_znode(c, zbr, znode, 0);
1592 			if (IS_ERR(child)) {
1593 				err = PTR_ERR(child);
1594 				goto out_unlock;
1595 			}
1596 			zbr->znode = child;
1597 		}
1598 
1599 		znode = child;
1600 	}
1601 
1602 	/* Iterate over all indexing nodes */
1603 	while (1) {
1604 		int idx;
1605 
1606 		cond_resched();
1607 
1608 		if (znode_cb) {
1609 			err = znode_cb(c, znode, priv);
1610 			if (err) {
1611 				ubifs_err(c, "znode checking function returned error %d",
1612 					  err);
1613 				ubifs_dump_znode(c, znode);
1614 				goto out_dump;
1615 			}
1616 		}
1617 		if (leaf_cb && znode->level == 0) {
1618 			for (idx = 0; idx < znode->child_cnt; idx++) {
1619 				zbr = &znode->zbranch[idx];
1620 				err = leaf_cb(c, zbr, priv);
1621 				if (err) {
1622 					ubifs_err(c, "leaf checking function returned error %d, for leaf at LEB %d:%d",
1623 						  err, zbr->lnum, zbr->offs);
1624 					goto out_dump;
1625 				}
1626 			}
1627 		}
1628 
1629 		if (!znode->parent)
1630 			break;
1631 
1632 		idx = znode->iip + 1;
1633 		znode = znode->parent;
1634 		if (idx < znode->child_cnt) {
1635 			/* Switch to the next index in the parent */
1636 			zbr = &znode->zbranch[idx];
1637 			child = zbr->znode;
1638 			if (!child) {
1639 				child = ubifs_load_znode(c, zbr, znode, idx);
1640 				if (IS_ERR(child)) {
1641 					err = PTR_ERR(child);
1642 					goto out_unlock;
1643 				}
1644 				zbr->znode = child;
1645 			}
1646 			znode = child;
1647 		} else
1648 			/*
1649 			 * This is the last child, switch to the parent and
1650 			 * continue.
1651 			 */
1652 			continue;
1653 
1654 		/* Go to the lowest leftmost znode in the new sub-tree */
1655 		while (znode->level > 0) {
1656 			zbr = &znode->zbranch[0];
1657 			child = zbr->znode;
1658 			if (!child) {
1659 				child = ubifs_load_znode(c, zbr, znode, 0);
1660 				if (IS_ERR(child)) {
1661 					err = PTR_ERR(child);
1662 					goto out_unlock;
1663 				}
1664 				zbr->znode = child;
1665 			}
1666 			znode = child;
1667 		}
1668 	}
1669 
1670 	mutex_unlock(&c->tnc_mutex);
1671 	return 0;
1672 
1673 out_dump:
1674 	if (znode->parent)
1675 		zbr = &znode->parent->zbranch[znode->iip];
1676 	else
1677 		zbr = &c->zroot;
1678 	ubifs_msg(c, "dump of znode at LEB %d:%d", zbr->lnum, zbr->offs);
1679 	ubifs_dump_znode(c, znode);
1680 out_unlock:
1681 	mutex_unlock(&c->tnc_mutex);
1682 	return err;
1683 }
1684 
1685 /**
1686  * add_size - add znode size to partially calculated index size.
1687  * @c: UBIFS file-system description object
1688  * @znode: znode to add size for
1689  * @priv: partially calculated index size
1690  *
1691  * This is a helper function for 'dbg_check_idx_size()' which is called for
1692  * every indexing node and adds its size to the 'long long' variable pointed to
1693  * by @priv.
1694  */
1695 static int add_size(struct ubifs_info *c, struct ubifs_znode *znode, void *priv)
1696 {
1697 	long long *idx_size = priv;
1698 	int add;
1699 
1700 	add = ubifs_idx_node_sz(c, znode->child_cnt);
1701 	add = ALIGN(add, 8);
1702 	*idx_size += add;
1703 	return 0;
1704 }
1705 
1706 /**
1707  * dbg_check_idx_size - check index size.
1708  * @c: UBIFS file-system description object
1709  * @idx_size: size to check
1710  *
1711  * This function walks the UBIFS index, calculates its size and checks that the
1712  * size is equivalent to @idx_size. Returns zero in case of success and a
1713  * negative error code in case of failure.
1714  */
1715 int dbg_check_idx_size(struct ubifs_info *c, long long idx_size)
1716 {
1717 	int err;
1718 	long long calc = 0;
1719 
1720 	if (!dbg_is_chk_index(c))
1721 		return 0;
1722 
1723 	err = dbg_walk_index(c, NULL, add_size, &calc);
1724 	if (err) {
1725 		ubifs_err(c, "error %d while walking the index", err);
1726 		return err;
1727 	}
1728 
1729 	if (calc != idx_size) {
1730 		ubifs_err(c, "index size check failed: calculated size is %lld, should be %lld",
1731 			  calc, idx_size);
1732 		dump_stack();
1733 		return -EINVAL;
1734 	}
1735 
1736 	return 0;
1737 }
1738 
1739 /**
1740  * struct fsck_inode - information about an inode used when checking the file-system.
1741  * @rb: link in the RB-tree of inodes
1742  * @inum: inode number
1743  * @mode: inode type, permissions, etc
1744  * @nlink: inode link count
1745  * @xattr_cnt: count of extended attributes
1746  * @references: how many directory/xattr entries refer this inode (calculated
1747  *              while walking the index)
1748  * @calc_cnt: for directory inode count of child directories
1749  * @size: inode size (read from on-flash inode)
1750  * @xattr_sz: summary size of all extended attributes (read from on-flash
1751  *            inode)
1752  * @calc_sz: for directories calculated directory size
1753  * @calc_xcnt: count of extended attributes
1754  * @calc_xsz: calculated summary size of all extended attributes
1755  * @xattr_nms: sum of lengths of all extended attribute names belonging to this
1756  *             inode (read from on-flash inode)
1757  * @calc_xnms: calculated sum of lengths of all extended attribute names
1758  */
1759 struct fsck_inode {
1760 	struct rb_node rb;
1761 	ino_t inum;
1762 	umode_t mode;
1763 	unsigned int nlink;
1764 	unsigned int xattr_cnt;
1765 	int references;
1766 	int calc_cnt;
1767 	long long size;
1768 	unsigned int xattr_sz;
1769 	long long calc_sz;
1770 	long long calc_xcnt;
1771 	long long calc_xsz;
1772 	unsigned int xattr_nms;
1773 	long long calc_xnms;
1774 };
1775 
1776 /**
1777  * struct fsck_data - private FS checking information.
1778  * @inodes: RB-tree of all inodes (contains @struct fsck_inode objects)
1779  */
1780 struct fsck_data {
1781 	struct rb_root inodes;
1782 };
1783 
1784 /**
1785  * add_inode - add inode information to RB-tree of inodes.
1786  * @c: UBIFS file-system description object
1787  * @fsckd: FS checking information
1788  * @ino: raw UBIFS inode to add
1789  *
1790  * This is a helper function for 'check_leaf()' which adds information about
1791  * inode @ino to the RB-tree of inodes. Returns inode information pointer in
1792  * case of success and a negative error code in case of failure.
1793  */
1794 static struct fsck_inode *add_inode(struct ubifs_info *c,
1795 				    struct fsck_data *fsckd,
1796 				    struct ubifs_ino_node *ino)
1797 {
1798 	struct rb_node **p, *parent = NULL;
1799 	struct fsck_inode *fscki;
1800 	ino_t inum = key_inum_flash(c, &ino->key);
1801 	struct inode *inode;
1802 	struct ubifs_inode *ui;
1803 
1804 	p = &fsckd->inodes.rb_node;
1805 	while (*p) {
1806 		parent = *p;
1807 		fscki = rb_entry(parent, struct fsck_inode, rb);
1808 		if (inum < fscki->inum)
1809 			p = &(*p)->rb_left;
1810 		else if (inum > fscki->inum)
1811 			p = &(*p)->rb_right;
1812 		else
1813 			return fscki;
1814 	}
1815 
1816 	if (inum > c->highest_inum) {
1817 		ubifs_err(c, "too high inode number, max. is %lu",
1818 			  (unsigned long)c->highest_inum);
1819 		return ERR_PTR(-EINVAL);
1820 	}
1821 
1822 	fscki = kzalloc(sizeof(struct fsck_inode), GFP_NOFS);
1823 	if (!fscki)
1824 		return ERR_PTR(-ENOMEM);
1825 
1826 	inode = ilookup(c->vfs_sb, inum);
1827 
1828 	fscki->inum = inum;
1829 	/*
1830 	 * If the inode is present in the VFS inode cache, use it instead of
1831 	 * the on-flash inode which might be out-of-date. E.g., the size might
1832 	 * be out-of-date. If we do not do this, the following may happen, for
1833 	 * example:
1834 	 *   1. A power cut happens
1835 	 *   2. We mount the file-system R/O, the replay process fixes up the
1836 	 *      inode size in the VFS cache, but on on-flash.
1837 	 *   3. 'check_leaf()' fails because it hits a data node beyond inode
1838 	 *      size.
1839 	 */
1840 	if (!inode) {
1841 		fscki->nlink = le32_to_cpu(ino->nlink);
1842 		fscki->size = le64_to_cpu(ino->size);
1843 		fscki->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
1844 		fscki->xattr_sz = le32_to_cpu(ino->xattr_size);
1845 		fscki->xattr_nms = le32_to_cpu(ino->xattr_names);
1846 		fscki->mode = le32_to_cpu(ino->mode);
1847 	} else {
1848 		ui = ubifs_inode(inode);
1849 		fscki->nlink = inode->i_nlink;
1850 		fscki->size = inode->i_size;
1851 		fscki->xattr_cnt = ui->xattr_cnt;
1852 		fscki->xattr_sz = ui->xattr_size;
1853 		fscki->xattr_nms = ui->xattr_names;
1854 		fscki->mode = inode->i_mode;
1855 		iput(inode);
1856 	}
1857 
1858 	if (S_ISDIR(fscki->mode)) {
1859 		fscki->calc_sz = UBIFS_INO_NODE_SZ;
1860 		fscki->calc_cnt = 2;
1861 	}
1862 
1863 	rb_link_node(&fscki->rb, parent, p);
1864 	rb_insert_color(&fscki->rb, &fsckd->inodes);
1865 
1866 	return fscki;
1867 }
1868 
1869 /**
1870  * search_inode - search inode in the RB-tree of inodes.
1871  * @fsckd: FS checking information
1872  * @inum: inode number to search
1873  *
1874  * This is a helper function for 'check_leaf()' which searches inode @inum in
1875  * the RB-tree of inodes and returns an inode information pointer or %NULL if
1876  * the inode was not found.
1877  */
1878 static struct fsck_inode *search_inode(struct fsck_data *fsckd, ino_t inum)
1879 {
1880 	struct rb_node *p;
1881 	struct fsck_inode *fscki;
1882 
1883 	p = fsckd->inodes.rb_node;
1884 	while (p) {
1885 		fscki = rb_entry(p, struct fsck_inode, rb);
1886 		if (inum < fscki->inum)
1887 			p = p->rb_left;
1888 		else if (inum > fscki->inum)
1889 			p = p->rb_right;
1890 		else
1891 			return fscki;
1892 	}
1893 	return NULL;
1894 }
1895 
1896 /**
1897  * read_add_inode - read inode node and add it to RB-tree of inodes.
1898  * @c: UBIFS file-system description object
1899  * @fsckd: FS checking information
1900  * @inum: inode number to read
1901  *
1902  * This is a helper function for 'check_leaf()' which finds inode node @inum in
1903  * the index, reads it, and adds it to the RB-tree of inodes. Returns inode
1904  * information pointer in case of success and a negative error code in case of
1905  * failure.
1906  */
1907 static struct fsck_inode *read_add_inode(struct ubifs_info *c,
1908 					 struct fsck_data *fsckd, ino_t inum)
1909 {
1910 	int n, err;
1911 	union ubifs_key key;
1912 	struct ubifs_znode *znode;
1913 	struct ubifs_zbranch *zbr;
1914 	struct ubifs_ino_node *ino;
1915 	struct fsck_inode *fscki;
1916 
1917 	fscki = search_inode(fsckd, inum);
1918 	if (fscki)
1919 		return fscki;
1920 
1921 	ino_key_init(c, &key, inum);
1922 	err = ubifs_lookup_level0(c, &key, &znode, &n);
1923 	if (!err) {
1924 		ubifs_err(c, "inode %lu not found in index", (unsigned long)inum);
1925 		return ERR_PTR(-ENOENT);
1926 	} else if (err < 0) {
1927 		ubifs_err(c, "error %d while looking up inode %lu",
1928 			  err, (unsigned long)inum);
1929 		return ERR_PTR(err);
1930 	}
1931 
1932 	zbr = &znode->zbranch[n];
1933 	if (zbr->len < UBIFS_INO_NODE_SZ) {
1934 		ubifs_err(c, "bad node %lu node length %d",
1935 			  (unsigned long)inum, zbr->len);
1936 		return ERR_PTR(-EINVAL);
1937 	}
1938 
1939 	ino = kmalloc(zbr->len, GFP_NOFS);
1940 	if (!ino)
1941 		return ERR_PTR(-ENOMEM);
1942 
1943 	err = ubifs_tnc_read_node(c, zbr, ino);
1944 	if (err) {
1945 		ubifs_err(c, "cannot read inode node at LEB %d:%d, error %d",
1946 			  zbr->lnum, zbr->offs, err);
1947 		kfree(ino);
1948 		return ERR_PTR(err);
1949 	}
1950 
1951 	fscki = add_inode(c, fsckd, ino);
1952 	kfree(ino);
1953 	if (IS_ERR(fscki)) {
1954 		ubifs_err(c, "error %ld while adding inode %lu node",
1955 			  PTR_ERR(fscki), (unsigned long)inum);
1956 		return fscki;
1957 	}
1958 
1959 	return fscki;
1960 }
1961 
1962 /**
1963  * check_leaf - check leaf node.
1964  * @c: UBIFS file-system description object
1965  * @zbr: zbranch of the leaf node to check
1966  * @priv: FS checking information
1967  *
1968  * This is a helper function for 'dbg_check_filesystem()' which is called for
1969  * every single leaf node while walking the indexing tree. It checks that the
1970  * leaf node referred from the indexing tree exists, has correct CRC, and does
1971  * some other basic validation. This function is also responsible for building
1972  * an RB-tree of inodes - it adds all inodes into the RB-tree. It also
1973  * calculates reference count, size, etc for each inode in order to later
1974  * compare them to the information stored inside the inodes and detect possible
1975  * inconsistencies. Returns zero in case of success and a negative error code
1976  * in case of failure.
1977  */
1978 static int check_leaf(struct ubifs_info *c, struct ubifs_zbranch *zbr,
1979 		      void *priv)
1980 {
1981 	ino_t inum;
1982 	void *node;
1983 	struct ubifs_ch *ch;
1984 	int err, type = key_type(c, &zbr->key);
1985 	struct fsck_inode *fscki;
1986 
1987 	if (zbr->len < UBIFS_CH_SZ) {
1988 		ubifs_err(c, "bad leaf length %d (LEB %d:%d)",
1989 			  zbr->len, zbr->lnum, zbr->offs);
1990 		return -EINVAL;
1991 	}
1992 
1993 	node = kmalloc(zbr->len, GFP_NOFS);
1994 	if (!node)
1995 		return -ENOMEM;
1996 
1997 	err = ubifs_tnc_read_node(c, zbr, node);
1998 	if (err) {
1999 		ubifs_err(c, "cannot read leaf node at LEB %d:%d, error %d",
2000 			  zbr->lnum, zbr->offs, err);
2001 		goto out_free;
2002 	}
2003 
2004 	/* If this is an inode node, add it to RB-tree of inodes */
2005 	if (type == UBIFS_INO_KEY) {
2006 		fscki = add_inode(c, priv, node);
2007 		if (IS_ERR(fscki)) {
2008 			err = PTR_ERR(fscki);
2009 			ubifs_err(c, "error %d while adding inode node", err);
2010 			goto out_dump;
2011 		}
2012 		goto out;
2013 	}
2014 
2015 	if (type != UBIFS_DENT_KEY && type != UBIFS_XENT_KEY &&
2016 	    type != UBIFS_DATA_KEY) {
2017 		ubifs_err(c, "unexpected node type %d at LEB %d:%d",
2018 			  type, zbr->lnum, zbr->offs);
2019 		err = -EINVAL;
2020 		goto out_free;
2021 	}
2022 
2023 	ch = node;
2024 	if (le64_to_cpu(ch->sqnum) > c->max_sqnum) {
2025 		ubifs_err(c, "too high sequence number, max. is %llu",
2026 			  c->max_sqnum);
2027 		err = -EINVAL;
2028 		goto out_dump;
2029 	}
2030 
2031 	if (type == UBIFS_DATA_KEY) {
2032 		long long blk_offs;
2033 		struct ubifs_data_node *dn = node;
2034 
2035 		ubifs_assert(zbr->len >= UBIFS_DATA_NODE_SZ);
2036 
2037 		/*
2038 		 * Search the inode node this data node belongs to and insert
2039 		 * it to the RB-tree of inodes.
2040 		 */
2041 		inum = key_inum_flash(c, &dn->key);
2042 		fscki = read_add_inode(c, priv, inum);
2043 		if (IS_ERR(fscki)) {
2044 			err = PTR_ERR(fscki);
2045 			ubifs_err(c, "error %d while processing data node and trying to find inode node %lu",
2046 				  err, (unsigned long)inum);
2047 			goto out_dump;
2048 		}
2049 
2050 		/* Make sure the data node is within inode size */
2051 		blk_offs = key_block_flash(c, &dn->key);
2052 		blk_offs <<= UBIFS_BLOCK_SHIFT;
2053 		blk_offs += le32_to_cpu(dn->size);
2054 		if (blk_offs > fscki->size) {
2055 			ubifs_err(c, "data node at LEB %d:%d is not within inode size %lld",
2056 				  zbr->lnum, zbr->offs, fscki->size);
2057 			err = -EINVAL;
2058 			goto out_dump;
2059 		}
2060 	} else {
2061 		int nlen;
2062 		struct ubifs_dent_node *dent = node;
2063 		struct fsck_inode *fscki1;
2064 
2065 		ubifs_assert(zbr->len >= UBIFS_DENT_NODE_SZ);
2066 
2067 		err = ubifs_validate_entry(c, dent);
2068 		if (err)
2069 			goto out_dump;
2070 
2071 		/*
2072 		 * Search the inode node this entry refers to and the parent
2073 		 * inode node and insert them to the RB-tree of inodes.
2074 		 */
2075 		inum = le64_to_cpu(dent->inum);
2076 		fscki = read_add_inode(c, priv, inum);
2077 		if (IS_ERR(fscki)) {
2078 			err = PTR_ERR(fscki);
2079 			ubifs_err(c, "error %d while processing entry node and trying to find inode node %lu",
2080 				  err, (unsigned long)inum);
2081 			goto out_dump;
2082 		}
2083 
2084 		/* Count how many direntries or xentries refers this inode */
2085 		fscki->references += 1;
2086 
2087 		inum = key_inum_flash(c, &dent->key);
2088 		fscki1 = read_add_inode(c, priv, inum);
2089 		if (IS_ERR(fscki1)) {
2090 			err = PTR_ERR(fscki1);
2091 			ubifs_err(c, "error %d while processing entry node and trying to find parent inode node %lu",
2092 				  err, (unsigned long)inum);
2093 			goto out_dump;
2094 		}
2095 
2096 		nlen = le16_to_cpu(dent->nlen);
2097 		if (type == UBIFS_XENT_KEY) {
2098 			fscki1->calc_xcnt += 1;
2099 			fscki1->calc_xsz += CALC_DENT_SIZE(nlen);
2100 			fscki1->calc_xsz += CALC_XATTR_BYTES(fscki->size);
2101 			fscki1->calc_xnms += nlen;
2102 		} else {
2103 			fscki1->calc_sz += CALC_DENT_SIZE(nlen);
2104 			if (dent->type == UBIFS_ITYPE_DIR)
2105 				fscki1->calc_cnt += 1;
2106 		}
2107 	}
2108 
2109 out:
2110 	kfree(node);
2111 	return 0;
2112 
2113 out_dump:
2114 	ubifs_msg(c, "dump of node at LEB %d:%d", zbr->lnum, zbr->offs);
2115 	ubifs_dump_node(c, node);
2116 out_free:
2117 	kfree(node);
2118 	return err;
2119 }
2120 
2121 /**
2122  * free_inodes - free RB-tree of inodes.
2123  * @fsckd: FS checking information
2124  */
2125 static void free_inodes(struct fsck_data *fsckd)
2126 {
2127 	struct fsck_inode *fscki, *n;
2128 
2129 	rbtree_postorder_for_each_entry_safe(fscki, n, &fsckd->inodes, rb)
2130 		kfree(fscki);
2131 }
2132 
2133 /**
2134  * check_inodes - checks all inodes.
2135  * @c: UBIFS file-system description object
2136  * @fsckd: FS checking information
2137  *
2138  * This is a helper function for 'dbg_check_filesystem()' which walks the
2139  * RB-tree of inodes after the index scan has been finished, and checks that
2140  * inode nlink, size, etc are correct. Returns zero if inodes are fine,
2141  * %-EINVAL if not, and a negative error code in case of failure.
2142  */
2143 static int check_inodes(struct ubifs_info *c, struct fsck_data *fsckd)
2144 {
2145 	int n, err;
2146 	union ubifs_key key;
2147 	struct ubifs_znode *znode;
2148 	struct ubifs_zbranch *zbr;
2149 	struct ubifs_ino_node *ino;
2150 	struct fsck_inode *fscki;
2151 	struct rb_node *this = rb_first(&fsckd->inodes);
2152 
2153 	while (this) {
2154 		fscki = rb_entry(this, struct fsck_inode, rb);
2155 		this = rb_next(this);
2156 
2157 		if (S_ISDIR(fscki->mode)) {
2158 			/*
2159 			 * Directories have to have exactly one reference (they
2160 			 * cannot have hardlinks), although root inode is an
2161 			 * exception.
2162 			 */
2163 			if (fscki->inum != UBIFS_ROOT_INO &&
2164 			    fscki->references != 1) {
2165 				ubifs_err(c, "directory inode %lu has %d direntries which refer it, but should be 1",
2166 					  (unsigned long)fscki->inum,
2167 					  fscki->references);
2168 				goto out_dump;
2169 			}
2170 			if (fscki->inum == UBIFS_ROOT_INO &&
2171 			    fscki->references != 0) {
2172 				ubifs_err(c, "root inode %lu has non-zero (%d) direntries which refer it",
2173 					  (unsigned long)fscki->inum,
2174 					  fscki->references);
2175 				goto out_dump;
2176 			}
2177 			if (fscki->calc_sz != fscki->size) {
2178 				ubifs_err(c, "directory inode %lu size is %lld, but calculated size is %lld",
2179 					  (unsigned long)fscki->inum,
2180 					  fscki->size, fscki->calc_sz);
2181 				goto out_dump;
2182 			}
2183 			if (fscki->calc_cnt != fscki->nlink) {
2184 				ubifs_err(c, "directory inode %lu nlink is %d, but calculated nlink is %d",
2185 					  (unsigned long)fscki->inum,
2186 					  fscki->nlink, fscki->calc_cnt);
2187 				goto out_dump;
2188 			}
2189 		} else {
2190 			if (fscki->references != fscki->nlink) {
2191 				ubifs_err(c, "inode %lu nlink is %d, but calculated nlink is %d",
2192 					  (unsigned long)fscki->inum,
2193 					  fscki->nlink, fscki->references);
2194 				goto out_dump;
2195 			}
2196 		}
2197 		if (fscki->xattr_sz != fscki->calc_xsz) {
2198 			ubifs_err(c, "inode %lu has xattr size %u, but calculated size is %lld",
2199 				  (unsigned long)fscki->inum, fscki->xattr_sz,
2200 				  fscki->calc_xsz);
2201 			goto out_dump;
2202 		}
2203 		if (fscki->xattr_cnt != fscki->calc_xcnt) {
2204 			ubifs_err(c, "inode %lu has %u xattrs, but calculated count is %lld",
2205 				  (unsigned long)fscki->inum,
2206 				  fscki->xattr_cnt, fscki->calc_xcnt);
2207 			goto out_dump;
2208 		}
2209 		if (fscki->xattr_nms != fscki->calc_xnms) {
2210 			ubifs_err(c, "inode %lu has xattr names' size %u, but calculated names' size is %lld",
2211 				  (unsigned long)fscki->inum, fscki->xattr_nms,
2212 				  fscki->calc_xnms);
2213 			goto out_dump;
2214 		}
2215 	}
2216 
2217 	return 0;
2218 
2219 out_dump:
2220 	/* Read the bad inode and dump it */
2221 	ino_key_init(c, &key, fscki->inum);
2222 	err = ubifs_lookup_level0(c, &key, &znode, &n);
2223 	if (!err) {
2224 		ubifs_err(c, "inode %lu not found in index",
2225 			  (unsigned long)fscki->inum);
2226 		return -ENOENT;
2227 	} else if (err < 0) {
2228 		ubifs_err(c, "error %d while looking up inode %lu",
2229 			  err, (unsigned long)fscki->inum);
2230 		return err;
2231 	}
2232 
2233 	zbr = &znode->zbranch[n];
2234 	ino = kmalloc(zbr->len, GFP_NOFS);
2235 	if (!ino)
2236 		return -ENOMEM;
2237 
2238 	err = ubifs_tnc_read_node(c, zbr, ino);
2239 	if (err) {
2240 		ubifs_err(c, "cannot read inode node at LEB %d:%d, error %d",
2241 			  zbr->lnum, zbr->offs, err);
2242 		kfree(ino);
2243 		return err;
2244 	}
2245 
2246 	ubifs_msg(c, "dump of the inode %lu sitting in LEB %d:%d",
2247 		  (unsigned long)fscki->inum, zbr->lnum, zbr->offs);
2248 	ubifs_dump_node(c, ino);
2249 	kfree(ino);
2250 	return -EINVAL;
2251 }
2252 
2253 /**
2254  * dbg_check_filesystem - check the file-system.
2255  * @c: UBIFS file-system description object
2256  *
2257  * This function checks the file system, namely:
2258  * o makes sure that all leaf nodes exist and their CRCs are correct;
2259  * o makes sure inode nlink, size, xattr size/count are correct (for all
2260  *   inodes).
2261  *
2262  * The function reads whole indexing tree and all nodes, so it is pretty
2263  * heavy-weight. Returns zero if the file-system is consistent, %-EINVAL if
2264  * not, and a negative error code in case of failure.
2265  */
2266 int dbg_check_filesystem(struct ubifs_info *c)
2267 {
2268 	int err;
2269 	struct fsck_data fsckd;
2270 
2271 	if (!dbg_is_chk_fs(c))
2272 		return 0;
2273 
2274 	fsckd.inodes = RB_ROOT;
2275 	err = dbg_walk_index(c, check_leaf, NULL, &fsckd);
2276 	if (err)
2277 		goto out_free;
2278 
2279 	err = check_inodes(c, &fsckd);
2280 	if (err)
2281 		goto out_free;
2282 
2283 	free_inodes(&fsckd);
2284 	return 0;
2285 
2286 out_free:
2287 	ubifs_err(c, "file-system check failed with error %d", err);
2288 	dump_stack();
2289 	free_inodes(&fsckd);
2290 	return err;
2291 }
2292 
2293 /**
2294  * dbg_check_data_nodes_order - check that list of data nodes is sorted.
2295  * @c: UBIFS file-system description object
2296  * @head: the list of nodes ('struct ubifs_scan_node' objects)
2297  *
2298  * This function returns zero if the list of data nodes is sorted correctly,
2299  * and %-EINVAL if not.
2300  */
2301 int dbg_check_data_nodes_order(struct ubifs_info *c, struct list_head *head)
2302 {
2303 	struct list_head *cur;
2304 	struct ubifs_scan_node *sa, *sb;
2305 
2306 	if (!dbg_is_chk_gen(c))
2307 		return 0;
2308 
2309 	for (cur = head->next; cur->next != head; cur = cur->next) {
2310 		ino_t inuma, inumb;
2311 		uint32_t blka, blkb;
2312 
2313 		cond_resched();
2314 		sa = container_of(cur, struct ubifs_scan_node, list);
2315 		sb = container_of(cur->next, struct ubifs_scan_node, list);
2316 
2317 		if (sa->type != UBIFS_DATA_NODE) {
2318 			ubifs_err(c, "bad node type %d", sa->type);
2319 			ubifs_dump_node(c, sa->node);
2320 			return -EINVAL;
2321 		}
2322 		if (sb->type != UBIFS_DATA_NODE) {
2323 			ubifs_err(c, "bad node type %d", sb->type);
2324 			ubifs_dump_node(c, sb->node);
2325 			return -EINVAL;
2326 		}
2327 
2328 		inuma = key_inum(c, &sa->key);
2329 		inumb = key_inum(c, &sb->key);
2330 
2331 		if (inuma < inumb)
2332 			continue;
2333 		if (inuma > inumb) {
2334 			ubifs_err(c, "larger inum %lu goes before inum %lu",
2335 				  (unsigned long)inuma, (unsigned long)inumb);
2336 			goto error_dump;
2337 		}
2338 
2339 		blka = key_block(c, &sa->key);
2340 		blkb = key_block(c, &sb->key);
2341 
2342 		if (blka > blkb) {
2343 			ubifs_err(c, "larger block %u goes before %u", blka, blkb);
2344 			goto error_dump;
2345 		}
2346 		if (blka == blkb) {
2347 			ubifs_err(c, "two data nodes for the same block");
2348 			goto error_dump;
2349 		}
2350 	}
2351 
2352 	return 0;
2353 
2354 error_dump:
2355 	ubifs_dump_node(c, sa->node);
2356 	ubifs_dump_node(c, sb->node);
2357 	return -EINVAL;
2358 }
2359 
2360 /**
2361  * dbg_check_nondata_nodes_order - check that list of data nodes is sorted.
2362  * @c: UBIFS file-system description object
2363  * @head: the list of nodes ('struct ubifs_scan_node' objects)
2364  *
2365  * This function returns zero if the list of non-data nodes is sorted correctly,
2366  * and %-EINVAL if not.
2367  */
2368 int dbg_check_nondata_nodes_order(struct ubifs_info *c, struct list_head *head)
2369 {
2370 	struct list_head *cur;
2371 	struct ubifs_scan_node *sa, *sb;
2372 
2373 	if (!dbg_is_chk_gen(c))
2374 		return 0;
2375 
2376 	for (cur = head->next; cur->next != head; cur = cur->next) {
2377 		ino_t inuma, inumb;
2378 		uint32_t hasha, hashb;
2379 
2380 		cond_resched();
2381 		sa = container_of(cur, struct ubifs_scan_node, list);
2382 		sb = container_of(cur->next, struct ubifs_scan_node, list);
2383 
2384 		if (sa->type != UBIFS_INO_NODE && sa->type != UBIFS_DENT_NODE &&
2385 		    sa->type != UBIFS_XENT_NODE) {
2386 			ubifs_err(c, "bad node type %d", sa->type);
2387 			ubifs_dump_node(c, sa->node);
2388 			return -EINVAL;
2389 		}
2390 		if (sa->type != UBIFS_INO_NODE && sa->type != UBIFS_DENT_NODE &&
2391 		    sa->type != UBIFS_XENT_NODE) {
2392 			ubifs_err(c, "bad node type %d", sb->type);
2393 			ubifs_dump_node(c, sb->node);
2394 			return -EINVAL;
2395 		}
2396 
2397 		if (sa->type != UBIFS_INO_NODE && sb->type == UBIFS_INO_NODE) {
2398 			ubifs_err(c, "non-inode node goes before inode node");
2399 			goto error_dump;
2400 		}
2401 
2402 		if (sa->type == UBIFS_INO_NODE && sb->type != UBIFS_INO_NODE)
2403 			continue;
2404 
2405 		if (sa->type == UBIFS_INO_NODE && sb->type == UBIFS_INO_NODE) {
2406 			/* Inode nodes are sorted in descending size order */
2407 			if (sa->len < sb->len) {
2408 				ubifs_err(c, "smaller inode node goes first");
2409 				goto error_dump;
2410 			}
2411 			continue;
2412 		}
2413 
2414 		/*
2415 		 * This is either a dentry or xentry, which should be sorted in
2416 		 * ascending (parent ino, hash) order.
2417 		 */
2418 		inuma = key_inum(c, &sa->key);
2419 		inumb = key_inum(c, &sb->key);
2420 
2421 		if (inuma < inumb)
2422 			continue;
2423 		if (inuma > inumb) {
2424 			ubifs_err(c, "larger inum %lu goes before inum %lu",
2425 				  (unsigned long)inuma, (unsigned long)inumb);
2426 			goto error_dump;
2427 		}
2428 
2429 		hasha = key_block(c, &sa->key);
2430 		hashb = key_block(c, &sb->key);
2431 
2432 		if (hasha > hashb) {
2433 			ubifs_err(c, "larger hash %u goes before %u",
2434 				  hasha, hashb);
2435 			goto error_dump;
2436 		}
2437 	}
2438 
2439 	return 0;
2440 
2441 error_dump:
2442 	ubifs_msg(c, "dumping first node");
2443 	ubifs_dump_node(c, sa->node);
2444 	ubifs_msg(c, "dumping second node");
2445 	ubifs_dump_node(c, sb->node);
2446 	return -EINVAL;
2447 	return 0;
2448 }
2449 
2450 static inline int chance(unsigned int n, unsigned int out_of)
2451 {
2452 	return !!((prandom_u32() % out_of) + 1 <= n);
2453 
2454 }
2455 
2456 static int power_cut_emulated(struct ubifs_info *c, int lnum, int write)
2457 {
2458 	struct ubifs_debug_info *d = c->dbg;
2459 
2460 	ubifs_assert(dbg_is_tst_rcvry(c));
2461 
2462 	if (!d->pc_cnt) {
2463 		/* First call - decide delay to the power cut */
2464 		if (chance(1, 2)) {
2465 			unsigned long delay;
2466 
2467 			if (chance(1, 2)) {
2468 				d->pc_delay = 1;
2469 				/* Fail within 1 minute */
2470 				delay = prandom_u32() % 60000;
2471 				d->pc_timeout = jiffies;
2472 				d->pc_timeout += msecs_to_jiffies(delay);
2473 				ubifs_warn(c, "failing after %lums", delay);
2474 			} else {
2475 				d->pc_delay = 2;
2476 				delay = prandom_u32() % 10000;
2477 				/* Fail within 10000 operations */
2478 				d->pc_cnt_max = delay;
2479 				ubifs_warn(c, "failing after %lu calls", delay);
2480 			}
2481 		}
2482 
2483 		d->pc_cnt += 1;
2484 	}
2485 
2486 	/* Determine if failure delay has expired */
2487 	if (d->pc_delay == 1 && time_before(jiffies, d->pc_timeout))
2488 			return 0;
2489 	if (d->pc_delay == 2 && d->pc_cnt++ < d->pc_cnt_max)
2490 			return 0;
2491 
2492 	if (lnum == UBIFS_SB_LNUM) {
2493 		if (write && chance(1, 2))
2494 			return 0;
2495 		if (chance(19, 20))
2496 			return 0;
2497 		ubifs_warn(c, "failing in super block LEB %d", lnum);
2498 	} else if (lnum == UBIFS_MST_LNUM || lnum == UBIFS_MST_LNUM + 1) {
2499 		if (chance(19, 20))
2500 			return 0;
2501 		ubifs_warn(c, "failing in master LEB %d", lnum);
2502 	} else if (lnum >= UBIFS_LOG_LNUM && lnum <= c->log_last) {
2503 		if (write && chance(99, 100))
2504 			return 0;
2505 		if (chance(399, 400))
2506 			return 0;
2507 		ubifs_warn(c, "failing in log LEB %d", lnum);
2508 	} else if (lnum >= c->lpt_first && lnum <= c->lpt_last) {
2509 		if (write && chance(7, 8))
2510 			return 0;
2511 		if (chance(19, 20))
2512 			return 0;
2513 		ubifs_warn(c, "failing in LPT LEB %d", lnum);
2514 	} else if (lnum >= c->orph_first && lnum <= c->orph_last) {
2515 		if (write && chance(1, 2))
2516 			return 0;
2517 		if (chance(9, 10))
2518 			return 0;
2519 		ubifs_warn(c, "failing in orphan LEB %d", lnum);
2520 	} else if (lnum == c->ihead_lnum) {
2521 		if (chance(99, 100))
2522 			return 0;
2523 		ubifs_warn(c, "failing in index head LEB %d", lnum);
2524 	} else if (c->jheads && lnum == c->jheads[GCHD].wbuf.lnum) {
2525 		if (chance(9, 10))
2526 			return 0;
2527 		ubifs_warn(c, "failing in GC head LEB %d", lnum);
2528 	} else if (write && !RB_EMPTY_ROOT(&c->buds) &&
2529 		   !ubifs_search_bud(c, lnum)) {
2530 		if (chance(19, 20))
2531 			return 0;
2532 		ubifs_warn(c, "failing in non-bud LEB %d", lnum);
2533 	} else if (c->cmt_state == COMMIT_RUNNING_BACKGROUND ||
2534 		   c->cmt_state == COMMIT_RUNNING_REQUIRED) {
2535 		if (chance(999, 1000))
2536 			return 0;
2537 		ubifs_warn(c, "failing in bud LEB %d commit running", lnum);
2538 	} else {
2539 		if (chance(9999, 10000))
2540 			return 0;
2541 		ubifs_warn(c, "failing in bud LEB %d commit not running", lnum);
2542 	}
2543 
2544 	d->pc_happened = 1;
2545 	ubifs_warn(c, "========== Power cut emulated ==========");
2546 	dump_stack();
2547 	return 1;
2548 }
2549 
2550 static int corrupt_data(const struct ubifs_info *c, const void *buf,
2551 			unsigned int len)
2552 {
2553 	unsigned int from, to, ffs = chance(1, 2);
2554 	unsigned char *p = (void *)buf;
2555 
2556 	from = prandom_u32() % len;
2557 	/* Corruption span max to end of write unit */
2558 	to = min(len, ALIGN(from + 1, c->max_write_size));
2559 
2560 	ubifs_warn(c, "filled bytes %u-%u with %s", from, to - 1,
2561 		   ffs ? "0xFFs" : "random data");
2562 
2563 	if (ffs)
2564 		memset(p + from, 0xFF, to - from);
2565 	else
2566 		prandom_bytes(p + from, to - from);
2567 
2568 	return to;
2569 }
2570 
2571 int dbg_leb_write(struct ubifs_info *c, int lnum, const void *buf,
2572 		  int offs, int len)
2573 {
2574 	int err, failing;
2575 
2576 	if (dbg_is_power_cut(c))
2577 		return -EROFS;
2578 
2579 	failing = power_cut_emulated(c, lnum, 1);
2580 	if (failing) {
2581 		len = corrupt_data(c, buf, len);
2582 		ubifs_warn(c, "actually write %d bytes to LEB %d:%d (the buffer was corrupted)",
2583 			   len, lnum, offs);
2584 	}
2585 	err = ubi_leb_write(c->ubi, lnum, buf, offs, len);
2586 	if (err)
2587 		return err;
2588 	if (failing)
2589 		return -EROFS;
2590 	return 0;
2591 }
2592 
2593 int dbg_leb_change(struct ubifs_info *c, int lnum, const void *buf,
2594 		   int len)
2595 {
2596 	int err;
2597 
2598 	if (dbg_is_power_cut(c))
2599 		return -EROFS;
2600 	if (power_cut_emulated(c, lnum, 1))
2601 		return -EROFS;
2602 	err = ubi_leb_change(c->ubi, lnum, buf, len);
2603 	if (err)
2604 		return err;
2605 	if (power_cut_emulated(c, lnum, 1))
2606 		return -EROFS;
2607 	return 0;
2608 }
2609 
2610 int dbg_leb_unmap(struct ubifs_info *c, int lnum)
2611 {
2612 	int err;
2613 
2614 	if (dbg_is_power_cut(c))
2615 		return -EROFS;
2616 	if (power_cut_emulated(c, lnum, 0))
2617 		return -EROFS;
2618 	err = ubi_leb_unmap(c->ubi, lnum);
2619 	if (err)
2620 		return err;
2621 	if (power_cut_emulated(c, lnum, 0))
2622 		return -EROFS;
2623 	return 0;
2624 }
2625 
2626 int dbg_leb_map(struct ubifs_info *c, int lnum)
2627 {
2628 	int err;
2629 
2630 	if (dbg_is_power_cut(c))
2631 		return -EROFS;
2632 	if (power_cut_emulated(c, lnum, 0))
2633 		return -EROFS;
2634 	err = ubi_leb_map(c->ubi, lnum);
2635 	if (err)
2636 		return err;
2637 	if (power_cut_emulated(c, lnum, 0))
2638 		return -EROFS;
2639 	return 0;
2640 }
2641 
2642 /*
2643  * Root directory for UBIFS stuff in debugfs. Contains sub-directories which
2644  * contain the stuff specific to particular file-system mounts.
2645  */
2646 static struct dentry *dfs_rootdir;
2647 
2648 static int dfs_file_open(struct inode *inode, struct file *file)
2649 {
2650 	file->private_data = inode->i_private;
2651 	return nonseekable_open(inode, file);
2652 }
2653 
2654 /**
2655  * provide_user_output - provide output to the user reading a debugfs file.
2656  * @val: boolean value for the answer
2657  * @u: the buffer to store the answer at
2658  * @count: size of the buffer
2659  * @ppos: position in the @u output buffer
2660  *
2661  * This is a simple helper function which stores @val boolean value in the user
2662  * buffer when the user reads one of UBIFS debugfs files. Returns amount of
2663  * bytes written to @u in case of success and a negative error code in case of
2664  * failure.
2665  */
2666 static int provide_user_output(int val, char __user *u, size_t count,
2667 			       loff_t *ppos)
2668 {
2669 	char buf[3];
2670 
2671 	if (val)
2672 		buf[0] = '1';
2673 	else
2674 		buf[0] = '0';
2675 	buf[1] = '\n';
2676 	buf[2] = 0x00;
2677 
2678 	return simple_read_from_buffer(u, count, ppos, buf, 2);
2679 }
2680 
2681 static ssize_t dfs_file_read(struct file *file, char __user *u, size_t count,
2682 			     loff_t *ppos)
2683 {
2684 	struct dentry *dent = file->f_path.dentry;
2685 	struct ubifs_info *c = file->private_data;
2686 	struct ubifs_debug_info *d = c->dbg;
2687 	int val;
2688 
2689 	if (dent == d->dfs_chk_gen)
2690 		val = d->chk_gen;
2691 	else if (dent == d->dfs_chk_index)
2692 		val = d->chk_index;
2693 	else if (dent == d->dfs_chk_orph)
2694 		val = d->chk_orph;
2695 	else if (dent == d->dfs_chk_lprops)
2696 		val = d->chk_lprops;
2697 	else if (dent == d->dfs_chk_fs)
2698 		val = d->chk_fs;
2699 	else if (dent == d->dfs_tst_rcvry)
2700 		val = d->tst_rcvry;
2701 	else if (dent == d->dfs_ro_error)
2702 		val = c->ro_error;
2703 	else
2704 		return -EINVAL;
2705 
2706 	return provide_user_output(val, u, count, ppos);
2707 }
2708 
2709 /**
2710  * interpret_user_input - interpret user debugfs file input.
2711  * @u: user-provided buffer with the input
2712  * @count: buffer size
2713  *
2714  * This is a helper function which interpret user input to a boolean UBIFS
2715  * debugfs file. Returns %0 or %1 in case of success and a negative error code
2716  * in case of failure.
2717  */
2718 static int interpret_user_input(const char __user *u, size_t count)
2719 {
2720 	size_t buf_size;
2721 	char buf[8];
2722 
2723 	buf_size = min_t(size_t, count, (sizeof(buf) - 1));
2724 	if (copy_from_user(buf, u, buf_size))
2725 		return -EFAULT;
2726 
2727 	if (buf[0] == '1')
2728 		return 1;
2729 	else if (buf[0] == '0')
2730 		return 0;
2731 
2732 	return -EINVAL;
2733 }
2734 
2735 static ssize_t dfs_file_write(struct file *file, const char __user *u,
2736 			      size_t count, loff_t *ppos)
2737 {
2738 	struct ubifs_info *c = file->private_data;
2739 	struct ubifs_debug_info *d = c->dbg;
2740 	struct dentry *dent = file->f_path.dentry;
2741 	int val;
2742 
2743 	/*
2744 	 * TODO: this is racy - the file-system might have already been
2745 	 * unmounted and we'd oops in this case. The plan is to fix it with
2746 	 * help of 'iterate_supers_type()' which we should have in v3.0: when
2747 	 * a debugfs opened, we rember FS's UUID in file->private_data. Then
2748 	 * whenever we access the FS via a debugfs file, we iterate all UBIFS
2749 	 * superblocks and fine the one with the same UUID, and take the
2750 	 * locking right.
2751 	 *
2752 	 * The other way to go suggested by Al Viro is to create a separate
2753 	 * 'ubifs-debug' file-system instead.
2754 	 */
2755 	if (file->f_path.dentry == d->dfs_dump_lprops) {
2756 		ubifs_dump_lprops(c);
2757 		return count;
2758 	}
2759 	if (file->f_path.dentry == d->dfs_dump_budg) {
2760 		ubifs_dump_budg(c, &c->bi);
2761 		return count;
2762 	}
2763 	if (file->f_path.dentry == d->dfs_dump_tnc) {
2764 		mutex_lock(&c->tnc_mutex);
2765 		ubifs_dump_tnc(c);
2766 		mutex_unlock(&c->tnc_mutex);
2767 		return count;
2768 	}
2769 
2770 	val = interpret_user_input(u, count);
2771 	if (val < 0)
2772 		return val;
2773 
2774 	if (dent == d->dfs_chk_gen)
2775 		d->chk_gen = val;
2776 	else if (dent == d->dfs_chk_index)
2777 		d->chk_index = val;
2778 	else if (dent == d->dfs_chk_orph)
2779 		d->chk_orph = val;
2780 	else if (dent == d->dfs_chk_lprops)
2781 		d->chk_lprops = val;
2782 	else if (dent == d->dfs_chk_fs)
2783 		d->chk_fs = val;
2784 	else if (dent == d->dfs_tst_rcvry)
2785 		d->tst_rcvry = val;
2786 	else if (dent == d->dfs_ro_error)
2787 		c->ro_error = !!val;
2788 	else
2789 		return -EINVAL;
2790 
2791 	return count;
2792 }
2793 
2794 static const struct file_operations dfs_fops = {
2795 	.open = dfs_file_open,
2796 	.read = dfs_file_read,
2797 	.write = dfs_file_write,
2798 	.owner = THIS_MODULE,
2799 	.llseek = no_llseek,
2800 };
2801 
2802 /**
2803  * dbg_debugfs_init_fs - initialize debugfs for UBIFS instance.
2804  * @c: UBIFS file-system description object
2805  *
2806  * This function creates all debugfs files for this instance of UBIFS. Returns
2807  * zero in case of success and a negative error code in case of failure.
2808  *
2809  * Note, the only reason we have not merged this function with the
2810  * 'ubifs_debugging_init()' function is because it is better to initialize
2811  * debugfs interfaces at the very end of the mount process, and remove them at
2812  * the very beginning of the mount process.
2813  */
2814 int dbg_debugfs_init_fs(struct ubifs_info *c)
2815 {
2816 	int err, n;
2817 	const char *fname;
2818 	struct dentry *dent;
2819 	struct ubifs_debug_info *d = c->dbg;
2820 
2821 	if (!IS_ENABLED(CONFIG_DEBUG_FS))
2822 		return 0;
2823 
2824 	n = snprintf(d->dfs_dir_name, UBIFS_DFS_DIR_LEN + 1, UBIFS_DFS_DIR_NAME,
2825 		     c->vi.ubi_num, c->vi.vol_id);
2826 	if (n == UBIFS_DFS_DIR_LEN) {
2827 		/* The array size is too small */
2828 		fname = UBIFS_DFS_DIR_NAME;
2829 		dent = ERR_PTR(-EINVAL);
2830 		goto out;
2831 	}
2832 
2833 	fname = d->dfs_dir_name;
2834 	dent = debugfs_create_dir(fname, dfs_rootdir);
2835 	if (IS_ERR_OR_NULL(dent))
2836 		goto out;
2837 	d->dfs_dir = dent;
2838 
2839 	fname = "dump_lprops";
2840 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c, &dfs_fops);
2841 	if (IS_ERR_OR_NULL(dent))
2842 		goto out_remove;
2843 	d->dfs_dump_lprops = dent;
2844 
2845 	fname = "dump_budg";
2846 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c, &dfs_fops);
2847 	if (IS_ERR_OR_NULL(dent))
2848 		goto out_remove;
2849 	d->dfs_dump_budg = dent;
2850 
2851 	fname = "dump_tnc";
2852 	dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, c, &dfs_fops);
2853 	if (IS_ERR_OR_NULL(dent))
2854 		goto out_remove;
2855 	d->dfs_dump_tnc = dent;
2856 
2857 	fname = "chk_general";
2858 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2859 				   &dfs_fops);
2860 	if (IS_ERR_OR_NULL(dent))
2861 		goto out_remove;
2862 	d->dfs_chk_gen = dent;
2863 
2864 	fname = "chk_index";
2865 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2866 				   &dfs_fops);
2867 	if (IS_ERR_OR_NULL(dent))
2868 		goto out_remove;
2869 	d->dfs_chk_index = dent;
2870 
2871 	fname = "chk_orphans";
2872 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2873 				   &dfs_fops);
2874 	if (IS_ERR_OR_NULL(dent))
2875 		goto out_remove;
2876 	d->dfs_chk_orph = dent;
2877 
2878 	fname = "chk_lprops";
2879 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2880 				   &dfs_fops);
2881 	if (IS_ERR_OR_NULL(dent))
2882 		goto out_remove;
2883 	d->dfs_chk_lprops = dent;
2884 
2885 	fname = "chk_fs";
2886 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2887 				   &dfs_fops);
2888 	if (IS_ERR_OR_NULL(dent))
2889 		goto out_remove;
2890 	d->dfs_chk_fs = dent;
2891 
2892 	fname = "tst_recovery";
2893 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2894 				   &dfs_fops);
2895 	if (IS_ERR_OR_NULL(dent))
2896 		goto out_remove;
2897 	d->dfs_tst_rcvry = dent;
2898 
2899 	fname = "ro_error";
2900 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, d->dfs_dir, c,
2901 				   &dfs_fops);
2902 	if (IS_ERR_OR_NULL(dent))
2903 		goto out_remove;
2904 	d->dfs_ro_error = dent;
2905 
2906 	return 0;
2907 
2908 out_remove:
2909 	debugfs_remove_recursive(d->dfs_dir);
2910 out:
2911 	err = dent ? PTR_ERR(dent) : -ENODEV;
2912 	ubifs_err(c, "cannot create \"%s\" debugfs file or directory, error %d\n",
2913 		  fname, err);
2914 	return err;
2915 }
2916 
2917 /**
2918  * dbg_debugfs_exit_fs - remove all debugfs files.
2919  * @c: UBIFS file-system description object
2920  */
2921 void dbg_debugfs_exit_fs(struct ubifs_info *c)
2922 {
2923 	if (IS_ENABLED(CONFIG_DEBUG_FS))
2924 		debugfs_remove_recursive(c->dbg->dfs_dir);
2925 }
2926 
2927 struct ubifs_global_debug_info ubifs_dbg;
2928 
2929 static struct dentry *dfs_chk_gen;
2930 static struct dentry *dfs_chk_index;
2931 static struct dentry *dfs_chk_orph;
2932 static struct dentry *dfs_chk_lprops;
2933 static struct dentry *dfs_chk_fs;
2934 static struct dentry *dfs_tst_rcvry;
2935 
2936 static ssize_t dfs_global_file_read(struct file *file, char __user *u,
2937 				    size_t count, loff_t *ppos)
2938 {
2939 	struct dentry *dent = file->f_path.dentry;
2940 	int val;
2941 
2942 	if (dent == dfs_chk_gen)
2943 		val = ubifs_dbg.chk_gen;
2944 	else if (dent == dfs_chk_index)
2945 		val = ubifs_dbg.chk_index;
2946 	else if (dent == dfs_chk_orph)
2947 		val = ubifs_dbg.chk_orph;
2948 	else if (dent == dfs_chk_lprops)
2949 		val = ubifs_dbg.chk_lprops;
2950 	else if (dent == dfs_chk_fs)
2951 		val = ubifs_dbg.chk_fs;
2952 	else if (dent == dfs_tst_rcvry)
2953 		val = ubifs_dbg.tst_rcvry;
2954 	else
2955 		return -EINVAL;
2956 
2957 	return provide_user_output(val, u, count, ppos);
2958 }
2959 
2960 static ssize_t dfs_global_file_write(struct file *file, const char __user *u,
2961 				     size_t count, loff_t *ppos)
2962 {
2963 	struct dentry *dent = file->f_path.dentry;
2964 	int val;
2965 
2966 	val = interpret_user_input(u, count);
2967 	if (val < 0)
2968 		return val;
2969 
2970 	if (dent == dfs_chk_gen)
2971 		ubifs_dbg.chk_gen = val;
2972 	else if (dent == dfs_chk_index)
2973 		ubifs_dbg.chk_index = val;
2974 	else if (dent == dfs_chk_orph)
2975 		ubifs_dbg.chk_orph = val;
2976 	else if (dent == dfs_chk_lprops)
2977 		ubifs_dbg.chk_lprops = val;
2978 	else if (dent == dfs_chk_fs)
2979 		ubifs_dbg.chk_fs = val;
2980 	else if (dent == dfs_tst_rcvry)
2981 		ubifs_dbg.tst_rcvry = val;
2982 	else
2983 		return -EINVAL;
2984 
2985 	return count;
2986 }
2987 
2988 static const struct file_operations dfs_global_fops = {
2989 	.read = dfs_global_file_read,
2990 	.write = dfs_global_file_write,
2991 	.owner = THIS_MODULE,
2992 	.llseek = no_llseek,
2993 };
2994 
2995 /**
2996  * dbg_debugfs_init - initialize debugfs file-system.
2997  *
2998  * UBIFS uses debugfs file-system to expose various debugging knobs to
2999  * user-space. This function creates "ubifs" directory in the debugfs
3000  * file-system. Returns zero in case of success and a negative error code in
3001  * case of failure.
3002  */
3003 int dbg_debugfs_init(void)
3004 {
3005 	int err;
3006 	const char *fname;
3007 	struct dentry *dent;
3008 
3009 	if (!IS_ENABLED(CONFIG_DEBUG_FS))
3010 		return 0;
3011 
3012 	fname = "ubifs";
3013 	dent = debugfs_create_dir(fname, NULL);
3014 	if (IS_ERR_OR_NULL(dent))
3015 		goto out;
3016 	dfs_rootdir = dent;
3017 
3018 	fname = "chk_general";
3019 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
3020 				   &dfs_global_fops);
3021 	if (IS_ERR_OR_NULL(dent))
3022 		goto out_remove;
3023 	dfs_chk_gen = dent;
3024 
3025 	fname = "chk_index";
3026 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
3027 				   &dfs_global_fops);
3028 	if (IS_ERR_OR_NULL(dent))
3029 		goto out_remove;
3030 	dfs_chk_index = dent;
3031 
3032 	fname = "chk_orphans";
3033 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
3034 				   &dfs_global_fops);
3035 	if (IS_ERR_OR_NULL(dent))
3036 		goto out_remove;
3037 	dfs_chk_orph = dent;
3038 
3039 	fname = "chk_lprops";
3040 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
3041 				   &dfs_global_fops);
3042 	if (IS_ERR_OR_NULL(dent))
3043 		goto out_remove;
3044 	dfs_chk_lprops = dent;
3045 
3046 	fname = "chk_fs";
3047 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
3048 				   &dfs_global_fops);
3049 	if (IS_ERR_OR_NULL(dent))
3050 		goto out_remove;
3051 	dfs_chk_fs = dent;
3052 
3053 	fname = "tst_recovery";
3054 	dent = debugfs_create_file(fname, S_IRUSR | S_IWUSR, dfs_rootdir, NULL,
3055 				   &dfs_global_fops);
3056 	if (IS_ERR_OR_NULL(dent))
3057 		goto out_remove;
3058 	dfs_tst_rcvry = dent;
3059 
3060 	return 0;
3061 
3062 out_remove:
3063 	debugfs_remove_recursive(dfs_rootdir);
3064 out:
3065 	err = dent ? PTR_ERR(dent) : -ENODEV;
3066 	pr_err("UBIFS error (pid %d): cannot create \"%s\" debugfs file or directory, error %d\n",
3067 	       current->pid, fname, err);
3068 	return err;
3069 }
3070 
3071 /**
3072  * dbg_debugfs_exit - remove the "ubifs" directory from debugfs file-system.
3073  */
3074 void dbg_debugfs_exit(void)
3075 {
3076 	if (IS_ENABLED(CONFIG_DEBUG_FS))
3077 		debugfs_remove_recursive(dfs_rootdir);
3078 }
3079 
3080 /**
3081  * ubifs_debugging_init - initialize UBIFS debugging.
3082  * @c: UBIFS file-system description object
3083  *
3084  * This function initializes debugging-related data for the file system.
3085  * Returns zero in case of success and a negative error code in case of
3086  * failure.
3087  */
3088 int ubifs_debugging_init(struct ubifs_info *c)
3089 {
3090 	c->dbg = kzalloc(sizeof(struct ubifs_debug_info), GFP_KERNEL);
3091 	if (!c->dbg)
3092 		return -ENOMEM;
3093 
3094 	return 0;
3095 }
3096 
3097 /**
3098  * ubifs_debugging_exit - free debugging data.
3099  * @c: UBIFS file-system description object
3100  */
3101 void ubifs_debugging_exit(struct ubifs_info *c)
3102 {
3103 	kfree(c->dbg);
3104 }
3105