xref: /openbmc/linux/fs/ubifs/lpt_commit.c (revision 4800cd83)
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: Adrian Hunter
20  *          Artem Bityutskiy (Битюцкий Артём)
21  */
22 
23 /*
24  * This file implements commit-related functionality of the LEB properties
25  * subsystem.
26  */
27 
28 #include <linux/crc16.h>
29 #include <linux/slab.h>
30 #include "ubifs.h"
31 
32 /**
33  * first_dirty_cnode - find first dirty cnode.
34  * @c: UBIFS file-system description object
35  * @nnode: nnode at which to start
36  *
37  * This function returns the first dirty cnode or %NULL if there is not one.
38  */
39 static struct ubifs_cnode *first_dirty_cnode(struct ubifs_nnode *nnode)
40 {
41 	ubifs_assert(nnode);
42 	while (1) {
43 		int i, cont = 0;
44 
45 		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
46 			struct ubifs_cnode *cnode;
47 
48 			cnode = nnode->nbranch[i].cnode;
49 			if (cnode &&
50 			    test_bit(DIRTY_CNODE, &cnode->flags)) {
51 				if (cnode->level == 0)
52 					return cnode;
53 				nnode = (struct ubifs_nnode *)cnode;
54 				cont = 1;
55 				break;
56 			}
57 		}
58 		if (!cont)
59 			return (struct ubifs_cnode *)nnode;
60 	}
61 }
62 
63 /**
64  * next_dirty_cnode - find next dirty cnode.
65  * @cnode: cnode from which to begin searching
66  *
67  * This function returns the next dirty cnode or %NULL if there is not one.
68  */
69 static struct ubifs_cnode *next_dirty_cnode(struct ubifs_cnode *cnode)
70 {
71 	struct ubifs_nnode *nnode;
72 	int i;
73 
74 	ubifs_assert(cnode);
75 	nnode = cnode->parent;
76 	if (!nnode)
77 		return NULL;
78 	for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) {
79 		cnode = nnode->nbranch[i].cnode;
80 		if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) {
81 			if (cnode->level == 0)
82 				return cnode; /* cnode is a pnode */
83 			/* cnode is a nnode */
84 			return first_dirty_cnode((struct ubifs_nnode *)cnode);
85 		}
86 	}
87 	return (struct ubifs_cnode *)nnode;
88 }
89 
90 /**
91  * get_cnodes_to_commit - create list of dirty cnodes to commit.
92  * @c: UBIFS file-system description object
93  *
94  * This function returns the number of cnodes to commit.
95  */
96 static int get_cnodes_to_commit(struct ubifs_info *c)
97 {
98 	struct ubifs_cnode *cnode, *cnext;
99 	int cnt = 0;
100 
101 	if (!c->nroot)
102 		return 0;
103 
104 	if (!test_bit(DIRTY_CNODE, &c->nroot->flags))
105 		return 0;
106 
107 	c->lpt_cnext = first_dirty_cnode(c->nroot);
108 	cnode = c->lpt_cnext;
109 	if (!cnode)
110 		return 0;
111 	cnt += 1;
112 	while (1) {
113 		ubifs_assert(!test_bit(COW_ZNODE, &cnode->flags));
114 		__set_bit(COW_ZNODE, &cnode->flags);
115 		cnext = next_dirty_cnode(cnode);
116 		if (!cnext) {
117 			cnode->cnext = c->lpt_cnext;
118 			break;
119 		}
120 		cnode->cnext = cnext;
121 		cnode = cnext;
122 		cnt += 1;
123 	}
124 	dbg_cmt("committing %d cnodes", cnt);
125 	dbg_lp("committing %d cnodes", cnt);
126 	ubifs_assert(cnt == c->dirty_nn_cnt + c->dirty_pn_cnt);
127 	return cnt;
128 }
129 
130 /**
131  * upd_ltab - update LPT LEB properties.
132  * @c: UBIFS file-system description object
133  * @lnum: LEB number
134  * @free: amount of free space
135  * @dirty: amount of dirty space to add
136  */
137 static void upd_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
138 {
139 	dbg_lp("LEB %d free %d dirty %d to %d +%d",
140 	       lnum, c->ltab[lnum - c->lpt_first].free,
141 	       c->ltab[lnum - c->lpt_first].dirty, free, dirty);
142 	ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
143 	c->ltab[lnum - c->lpt_first].free = free;
144 	c->ltab[lnum - c->lpt_first].dirty += dirty;
145 }
146 
147 /**
148  * alloc_lpt_leb - allocate an LPT LEB that is empty.
149  * @c: UBIFS file-system description object
150  * @lnum: LEB number is passed and returned here
151  *
152  * This function finds the next empty LEB in the ltab starting from @lnum. If a
153  * an empty LEB is found it is returned in @lnum and the function returns %0.
154  * Otherwise the function returns -ENOSPC.  Note however, that LPT is designed
155  * never to run out of space.
156  */
157 static int alloc_lpt_leb(struct ubifs_info *c, int *lnum)
158 {
159 	int i, n;
160 
161 	n = *lnum - c->lpt_first + 1;
162 	for (i = n; i < c->lpt_lebs; i++) {
163 		if (c->ltab[i].tgc || c->ltab[i].cmt)
164 			continue;
165 		if (c->ltab[i].free == c->leb_size) {
166 			c->ltab[i].cmt = 1;
167 			*lnum = i + c->lpt_first;
168 			return 0;
169 		}
170 	}
171 
172 	for (i = 0; i < n; i++) {
173 		if (c->ltab[i].tgc || c->ltab[i].cmt)
174 			continue;
175 		if (c->ltab[i].free == c->leb_size) {
176 			c->ltab[i].cmt = 1;
177 			*lnum = i + c->lpt_first;
178 			return 0;
179 		}
180 	}
181 	return -ENOSPC;
182 }
183 
184 /**
185  * layout_cnodes - layout cnodes for commit.
186  * @c: UBIFS file-system description object
187  *
188  * This function returns %0 on success and a negative error code on failure.
189  */
190 static int layout_cnodes(struct ubifs_info *c)
191 {
192 	int lnum, offs, len, alen, done_lsave, done_ltab, err;
193 	struct ubifs_cnode *cnode;
194 
195 	err = dbg_chk_lpt_sz(c, 0, 0);
196 	if (err)
197 		return err;
198 	cnode = c->lpt_cnext;
199 	if (!cnode)
200 		return 0;
201 	lnum = c->nhead_lnum;
202 	offs = c->nhead_offs;
203 	/* Try to place lsave and ltab nicely */
204 	done_lsave = !c->big_lpt;
205 	done_ltab = 0;
206 	if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
207 		done_lsave = 1;
208 		c->lsave_lnum = lnum;
209 		c->lsave_offs = offs;
210 		offs += c->lsave_sz;
211 		dbg_chk_lpt_sz(c, 1, c->lsave_sz);
212 	}
213 
214 	if (offs + c->ltab_sz <= c->leb_size) {
215 		done_ltab = 1;
216 		c->ltab_lnum = lnum;
217 		c->ltab_offs = offs;
218 		offs += c->ltab_sz;
219 		dbg_chk_lpt_sz(c, 1, c->ltab_sz);
220 	}
221 
222 	do {
223 		if (cnode->level) {
224 			len = c->nnode_sz;
225 			c->dirty_nn_cnt -= 1;
226 		} else {
227 			len = c->pnode_sz;
228 			c->dirty_pn_cnt -= 1;
229 		}
230 		while (offs + len > c->leb_size) {
231 			alen = ALIGN(offs, c->min_io_size);
232 			upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
233 			dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
234 			err = alloc_lpt_leb(c, &lnum);
235 			if (err)
236 				goto no_space;
237 			offs = 0;
238 			ubifs_assert(lnum >= c->lpt_first &&
239 				     lnum <= c->lpt_last);
240 			/* Try to place lsave and ltab nicely */
241 			if (!done_lsave) {
242 				done_lsave = 1;
243 				c->lsave_lnum = lnum;
244 				c->lsave_offs = offs;
245 				offs += c->lsave_sz;
246 				dbg_chk_lpt_sz(c, 1, c->lsave_sz);
247 				continue;
248 			}
249 			if (!done_ltab) {
250 				done_ltab = 1;
251 				c->ltab_lnum = lnum;
252 				c->ltab_offs = offs;
253 				offs += c->ltab_sz;
254 				dbg_chk_lpt_sz(c, 1, c->ltab_sz);
255 				continue;
256 			}
257 			break;
258 		}
259 		if (cnode->parent) {
260 			cnode->parent->nbranch[cnode->iip].lnum = lnum;
261 			cnode->parent->nbranch[cnode->iip].offs = offs;
262 		} else {
263 			c->lpt_lnum = lnum;
264 			c->lpt_offs = offs;
265 		}
266 		offs += len;
267 		dbg_chk_lpt_sz(c, 1, len);
268 		cnode = cnode->cnext;
269 	} while (cnode && cnode != c->lpt_cnext);
270 
271 	/* Make sure to place LPT's save table */
272 	if (!done_lsave) {
273 		if (offs + c->lsave_sz > c->leb_size) {
274 			alen = ALIGN(offs, c->min_io_size);
275 			upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
276 			dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
277 			err = alloc_lpt_leb(c, &lnum);
278 			if (err)
279 				goto no_space;
280 			offs = 0;
281 			ubifs_assert(lnum >= c->lpt_first &&
282 				     lnum <= c->lpt_last);
283 		}
284 		done_lsave = 1;
285 		c->lsave_lnum = lnum;
286 		c->lsave_offs = offs;
287 		offs += c->lsave_sz;
288 		dbg_chk_lpt_sz(c, 1, c->lsave_sz);
289 	}
290 
291 	/* Make sure to place LPT's own lprops table */
292 	if (!done_ltab) {
293 		if (offs + c->ltab_sz > c->leb_size) {
294 			alen = ALIGN(offs, c->min_io_size);
295 			upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
296 			dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
297 			err = alloc_lpt_leb(c, &lnum);
298 			if (err)
299 				goto no_space;
300 			offs = 0;
301 			ubifs_assert(lnum >= c->lpt_first &&
302 				     lnum <= c->lpt_last);
303 		}
304 		done_ltab = 1;
305 		c->ltab_lnum = lnum;
306 		c->ltab_offs = offs;
307 		offs += c->ltab_sz;
308 		dbg_chk_lpt_sz(c, 1, c->ltab_sz);
309 	}
310 
311 	alen = ALIGN(offs, c->min_io_size);
312 	upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
313 	dbg_chk_lpt_sz(c, 4, alen - offs);
314 	err = dbg_chk_lpt_sz(c, 3, alen);
315 	if (err)
316 		return err;
317 	return 0;
318 
319 no_space:
320 	ubifs_err("LPT out of space");
321 	dbg_err("LPT out of space at LEB %d:%d needing %d, done_ltab %d, "
322 		"done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
323 	dbg_dump_lpt_info(c);
324 	dbg_dump_lpt_lebs(c);
325 	dump_stack();
326 	return err;
327 }
328 
329 /**
330  * realloc_lpt_leb - allocate an LPT LEB that is empty.
331  * @c: UBIFS file-system description object
332  * @lnum: LEB number is passed and returned here
333  *
334  * This function duplicates exactly the results of the function alloc_lpt_leb.
335  * It is used during end commit to reallocate the same LEB numbers that were
336  * allocated by alloc_lpt_leb during start commit.
337  *
338  * This function finds the next LEB that was allocated by the alloc_lpt_leb
339  * function starting from @lnum. If a LEB is found it is returned in @lnum and
340  * the function returns %0. Otherwise the function returns -ENOSPC.
341  * Note however, that LPT is designed never to run out of space.
342  */
343 static int realloc_lpt_leb(struct ubifs_info *c, int *lnum)
344 {
345 	int i, n;
346 
347 	n = *lnum - c->lpt_first + 1;
348 	for (i = n; i < c->lpt_lebs; i++)
349 		if (c->ltab[i].cmt) {
350 			c->ltab[i].cmt = 0;
351 			*lnum = i + c->lpt_first;
352 			return 0;
353 		}
354 
355 	for (i = 0; i < n; i++)
356 		if (c->ltab[i].cmt) {
357 			c->ltab[i].cmt = 0;
358 			*lnum = i + c->lpt_first;
359 			return 0;
360 		}
361 	return -ENOSPC;
362 }
363 
364 /**
365  * write_cnodes - write cnodes for commit.
366  * @c: UBIFS file-system description object
367  *
368  * This function returns %0 on success and a negative error code on failure.
369  */
370 static int write_cnodes(struct ubifs_info *c)
371 {
372 	int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave;
373 	struct ubifs_cnode *cnode;
374 	void *buf = c->lpt_buf;
375 
376 	cnode = c->lpt_cnext;
377 	if (!cnode)
378 		return 0;
379 	lnum = c->nhead_lnum;
380 	offs = c->nhead_offs;
381 	from = offs;
382 	/* Ensure empty LEB is unmapped */
383 	if (offs == 0) {
384 		err = ubifs_leb_unmap(c, lnum);
385 		if (err)
386 			return err;
387 	}
388 	/* Try to place lsave and ltab nicely */
389 	done_lsave = !c->big_lpt;
390 	done_ltab = 0;
391 	if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
392 		done_lsave = 1;
393 		ubifs_pack_lsave(c, buf + offs, c->lsave);
394 		offs += c->lsave_sz;
395 		dbg_chk_lpt_sz(c, 1, c->lsave_sz);
396 	}
397 
398 	if (offs + c->ltab_sz <= c->leb_size) {
399 		done_ltab = 1;
400 		ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
401 		offs += c->ltab_sz;
402 		dbg_chk_lpt_sz(c, 1, c->ltab_sz);
403 	}
404 
405 	/* Loop for each cnode */
406 	do {
407 		if (cnode->level)
408 			len = c->nnode_sz;
409 		else
410 			len = c->pnode_sz;
411 		while (offs + len > c->leb_size) {
412 			wlen = offs - from;
413 			if (wlen) {
414 				alen = ALIGN(wlen, c->min_io_size);
415 				memset(buf + offs, 0xff, alen - wlen);
416 				err = ubifs_leb_write(c, lnum, buf + from, from,
417 						       alen, UBI_SHORTTERM);
418 				if (err)
419 					return err;
420 			}
421 			dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
422 			err = realloc_lpt_leb(c, &lnum);
423 			if (err)
424 				goto no_space;
425 			offs = from = 0;
426 			ubifs_assert(lnum >= c->lpt_first &&
427 				     lnum <= c->lpt_last);
428 			err = ubifs_leb_unmap(c, lnum);
429 			if (err)
430 				return err;
431 			/* Try to place lsave and ltab nicely */
432 			if (!done_lsave) {
433 				done_lsave = 1;
434 				ubifs_pack_lsave(c, buf + offs, c->lsave);
435 				offs += c->lsave_sz;
436 				dbg_chk_lpt_sz(c, 1, c->lsave_sz);
437 				continue;
438 			}
439 			if (!done_ltab) {
440 				done_ltab = 1;
441 				ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
442 				offs += c->ltab_sz;
443 				dbg_chk_lpt_sz(c, 1, c->ltab_sz);
444 				continue;
445 			}
446 			break;
447 		}
448 		if (cnode->level)
449 			ubifs_pack_nnode(c, buf + offs,
450 					 (struct ubifs_nnode *)cnode);
451 		else
452 			ubifs_pack_pnode(c, buf + offs,
453 					 (struct ubifs_pnode *)cnode);
454 		/*
455 		 * The reason for the barriers is the same as in case of TNC.
456 		 * See comment in 'write_index()'. 'dirty_cow_nnode()' and
457 		 * 'dirty_cow_pnode()' are the functions for which this is
458 		 * important.
459 		 */
460 		clear_bit(DIRTY_CNODE, &cnode->flags);
461 		smp_mb__before_clear_bit();
462 		clear_bit(COW_ZNODE, &cnode->flags);
463 		smp_mb__after_clear_bit();
464 		offs += len;
465 		dbg_chk_lpt_sz(c, 1, len);
466 		cnode = cnode->cnext;
467 	} while (cnode && cnode != c->lpt_cnext);
468 
469 	/* Make sure to place LPT's save table */
470 	if (!done_lsave) {
471 		if (offs + c->lsave_sz > c->leb_size) {
472 			wlen = offs - from;
473 			alen = ALIGN(wlen, c->min_io_size);
474 			memset(buf + offs, 0xff, alen - wlen);
475 			err = ubifs_leb_write(c, lnum, buf + from, from, alen,
476 					      UBI_SHORTTERM);
477 			if (err)
478 				return err;
479 			dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
480 			err = realloc_lpt_leb(c, &lnum);
481 			if (err)
482 				goto no_space;
483 			offs = from = 0;
484 			ubifs_assert(lnum >= c->lpt_first &&
485 				     lnum <= c->lpt_last);
486 			err = ubifs_leb_unmap(c, lnum);
487 			if (err)
488 				return err;
489 		}
490 		done_lsave = 1;
491 		ubifs_pack_lsave(c, buf + offs, c->lsave);
492 		offs += c->lsave_sz;
493 		dbg_chk_lpt_sz(c, 1, c->lsave_sz);
494 	}
495 
496 	/* Make sure to place LPT's own lprops table */
497 	if (!done_ltab) {
498 		if (offs + c->ltab_sz > c->leb_size) {
499 			wlen = offs - from;
500 			alen = ALIGN(wlen, c->min_io_size);
501 			memset(buf + offs, 0xff, alen - wlen);
502 			err = ubifs_leb_write(c, lnum, buf + from, from, alen,
503 					      UBI_SHORTTERM);
504 			if (err)
505 				return err;
506 			dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
507 			err = realloc_lpt_leb(c, &lnum);
508 			if (err)
509 				goto no_space;
510 			offs = from = 0;
511 			ubifs_assert(lnum >= c->lpt_first &&
512 				     lnum <= c->lpt_last);
513 			err = ubifs_leb_unmap(c, lnum);
514 			if (err)
515 				return err;
516 		}
517 		done_ltab = 1;
518 		ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
519 		offs += c->ltab_sz;
520 		dbg_chk_lpt_sz(c, 1, c->ltab_sz);
521 	}
522 
523 	/* Write remaining data in buffer */
524 	wlen = offs - from;
525 	alen = ALIGN(wlen, c->min_io_size);
526 	memset(buf + offs, 0xff, alen - wlen);
527 	err = ubifs_leb_write(c, lnum, buf + from, from, alen, UBI_SHORTTERM);
528 	if (err)
529 		return err;
530 
531 	dbg_chk_lpt_sz(c, 4, alen - wlen);
532 	err = dbg_chk_lpt_sz(c, 3, ALIGN(offs, c->min_io_size));
533 	if (err)
534 		return err;
535 
536 	c->nhead_lnum = lnum;
537 	c->nhead_offs = ALIGN(offs, c->min_io_size);
538 
539 	dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
540 	dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
541 	dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
542 	if (c->big_lpt)
543 		dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
544 
545 	return 0;
546 
547 no_space:
548 	ubifs_err("LPT out of space mismatch");
549 	dbg_err("LPT out of space mismatch at LEB %d:%d needing %d, done_ltab "
550 		"%d, done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
551 	dbg_dump_lpt_info(c);
552 	dbg_dump_lpt_lebs(c);
553 	dump_stack();
554 	return err;
555 }
556 
557 /**
558  * next_pnode_to_dirty - find next pnode to dirty.
559  * @c: UBIFS file-system description object
560  * @pnode: pnode
561  *
562  * This function returns the next pnode to dirty or %NULL if there are no more
563  * pnodes.  Note that pnodes that have never been written (lnum == 0) are
564  * skipped.
565  */
566 static struct ubifs_pnode *next_pnode_to_dirty(struct ubifs_info *c,
567 					       struct ubifs_pnode *pnode)
568 {
569 	struct ubifs_nnode *nnode;
570 	int iip;
571 
572 	/* Try to go right */
573 	nnode = pnode->parent;
574 	for (iip = pnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
575 		if (nnode->nbranch[iip].lnum)
576 			return ubifs_get_pnode(c, nnode, iip);
577 	}
578 
579 	/* Go up while can't go right */
580 	do {
581 		iip = nnode->iip + 1;
582 		nnode = nnode->parent;
583 		if (!nnode)
584 			return NULL;
585 		for (; iip < UBIFS_LPT_FANOUT; iip++) {
586 			if (nnode->nbranch[iip].lnum)
587 				break;
588 		}
589        } while (iip >= UBIFS_LPT_FANOUT);
590 
591 	/* Go right */
592 	nnode = ubifs_get_nnode(c, nnode, iip);
593 	if (IS_ERR(nnode))
594 		return (void *)nnode;
595 
596 	/* Go down to level 1 */
597 	while (nnode->level > 1) {
598 		for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) {
599 			if (nnode->nbranch[iip].lnum)
600 				break;
601 		}
602 		if (iip >= UBIFS_LPT_FANOUT) {
603 			/*
604 			 * Should not happen, but we need to keep going
605 			 * if it does.
606 			 */
607 			iip = 0;
608 		}
609 		nnode = ubifs_get_nnode(c, nnode, iip);
610 		if (IS_ERR(nnode))
611 			return (void *)nnode;
612 	}
613 
614 	for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++)
615 		if (nnode->nbranch[iip].lnum)
616 			break;
617 	if (iip >= UBIFS_LPT_FANOUT)
618 		/* Should not happen, but we need to keep going if it does */
619 		iip = 0;
620 	return ubifs_get_pnode(c, nnode, iip);
621 }
622 
623 /**
624  * pnode_lookup - lookup a pnode in the LPT.
625  * @c: UBIFS file-system description object
626  * @i: pnode number (0 to main_lebs - 1)
627  *
628  * This function returns a pointer to the pnode on success or a negative
629  * error code on failure.
630  */
631 static struct ubifs_pnode *pnode_lookup(struct ubifs_info *c, int i)
632 {
633 	int err, h, iip, shft;
634 	struct ubifs_nnode *nnode;
635 
636 	if (!c->nroot) {
637 		err = ubifs_read_nnode(c, NULL, 0);
638 		if (err)
639 			return ERR_PTR(err);
640 	}
641 	i <<= UBIFS_LPT_FANOUT_SHIFT;
642 	nnode = c->nroot;
643 	shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
644 	for (h = 1; h < c->lpt_hght; h++) {
645 		iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
646 		shft -= UBIFS_LPT_FANOUT_SHIFT;
647 		nnode = ubifs_get_nnode(c, nnode, iip);
648 		if (IS_ERR(nnode))
649 			return ERR_CAST(nnode);
650 	}
651 	iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
652 	return ubifs_get_pnode(c, nnode, iip);
653 }
654 
655 /**
656  * add_pnode_dirt - add dirty space to LPT LEB properties.
657  * @c: UBIFS file-system description object
658  * @pnode: pnode for which to add dirt
659  */
660 static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
661 {
662 	ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
663 			   c->pnode_sz);
664 }
665 
666 /**
667  * do_make_pnode_dirty - mark a pnode dirty.
668  * @c: UBIFS file-system description object
669  * @pnode: pnode to mark dirty
670  */
671 static void do_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode)
672 {
673 	/* Assumes cnext list is empty i.e. not called during commit */
674 	if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
675 		struct ubifs_nnode *nnode;
676 
677 		c->dirty_pn_cnt += 1;
678 		add_pnode_dirt(c, pnode);
679 		/* Mark parent and ancestors dirty too */
680 		nnode = pnode->parent;
681 		while (nnode) {
682 			if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
683 				c->dirty_nn_cnt += 1;
684 				ubifs_add_nnode_dirt(c, nnode);
685 				nnode = nnode->parent;
686 			} else
687 				break;
688 		}
689 	}
690 }
691 
692 /**
693  * make_tree_dirty - mark the entire LEB properties tree dirty.
694  * @c: UBIFS file-system description object
695  *
696  * This function is used by the "small" LPT model to cause the entire LEB
697  * properties tree to be written.  The "small" LPT model does not use LPT
698  * garbage collection because it is more efficient to write the entire tree
699  * (because it is small).
700  *
701  * This function returns %0 on success and a negative error code on failure.
702  */
703 static int make_tree_dirty(struct ubifs_info *c)
704 {
705 	struct ubifs_pnode *pnode;
706 
707 	pnode = pnode_lookup(c, 0);
708 	if (IS_ERR(pnode))
709 		return PTR_ERR(pnode);
710 
711 	while (pnode) {
712 		do_make_pnode_dirty(c, pnode);
713 		pnode = next_pnode_to_dirty(c, pnode);
714 		if (IS_ERR(pnode))
715 			return PTR_ERR(pnode);
716 	}
717 	return 0;
718 }
719 
720 /**
721  * need_write_all - determine if the LPT area is running out of free space.
722  * @c: UBIFS file-system description object
723  *
724  * This function returns %1 if the LPT area is running out of free space and %0
725  * if it is not.
726  */
727 static int need_write_all(struct ubifs_info *c)
728 {
729 	long long free = 0;
730 	int i;
731 
732 	for (i = 0; i < c->lpt_lebs; i++) {
733 		if (i + c->lpt_first == c->nhead_lnum)
734 			free += c->leb_size - c->nhead_offs;
735 		else if (c->ltab[i].free == c->leb_size)
736 			free += c->leb_size;
737 		else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
738 			free += c->leb_size;
739 	}
740 	/* Less than twice the size left */
741 	if (free <= c->lpt_sz * 2)
742 		return 1;
743 	return 0;
744 }
745 
746 /**
747  * lpt_tgc_start - start trivial garbage collection of LPT LEBs.
748  * @c: UBIFS file-system description object
749  *
750  * LPT trivial garbage collection is where a LPT LEB contains only dirty and
751  * free space and so may be reused as soon as the next commit is completed.
752  * This function is called during start commit to mark LPT LEBs for trivial GC.
753  */
754 static void lpt_tgc_start(struct ubifs_info *c)
755 {
756 	int i;
757 
758 	for (i = 0; i < c->lpt_lebs; i++) {
759 		if (i + c->lpt_first == c->nhead_lnum)
760 			continue;
761 		if (c->ltab[i].dirty > 0 &&
762 		    c->ltab[i].free + c->ltab[i].dirty == c->leb_size) {
763 			c->ltab[i].tgc = 1;
764 			c->ltab[i].free = c->leb_size;
765 			c->ltab[i].dirty = 0;
766 			dbg_lp("LEB %d", i + c->lpt_first);
767 		}
768 	}
769 }
770 
771 /**
772  * lpt_tgc_end - end trivial garbage collection of LPT LEBs.
773  * @c: UBIFS file-system description object
774  *
775  * LPT trivial garbage collection is where a LPT LEB contains only dirty and
776  * free space and so may be reused as soon as the next commit is completed.
777  * This function is called after the commit is completed (master node has been
778  * written) and un-maps LPT LEBs that were marked for trivial GC.
779  */
780 static int lpt_tgc_end(struct ubifs_info *c)
781 {
782 	int i, err;
783 
784 	for (i = 0; i < c->lpt_lebs; i++)
785 		if (c->ltab[i].tgc) {
786 			err = ubifs_leb_unmap(c, i + c->lpt_first);
787 			if (err)
788 				return err;
789 			c->ltab[i].tgc = 0;
790 			dbg_lp("LEB %d", i + c->lpt_first);
791 		}
792 	return 0;
793 }
794 
795 /**
796  * populate_lsave - fill the lsave array with important LEB numbers.
797  * @c: the UBIFS file-system description object
798  *
799  * This function is only called for the "big" model. It records a small number
800  * of LEB numbers of important LEBs.  Important LEBs are ones that are (from
801  * most important to least important): empty, freeable, freeable index, dirty
802  * index, dirty or free. Upon mount, we read this list of LEB numbers and bring
803  * their pnodes into memory.  That will stop us from having to scan the LPT
804  * straight away. For the "small" model we assume that scanning the LPT is no
805  * big deal.
806  */
807 static void populate_lsave(struct ubifs_info *c)
808 {
809 	struct ubifs_lprops *lprops;
810 	struct ubifs_lpt_heap *heap;
811 	int i, cnt = 0;
812 
813 	ubifs_assert(c->big_lpt);
814 	if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
815 		c->lpt_drty_flgs |= LSAVE_DIRTY;
816 		ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
817 	}
818 	list_for_each_entry(lprops, &c->empty_list, list) {
819 		c->lsave[cnt++] = lprops->lnum;
820 		if (cnt >= c->lsave_cnt)
821 			return;
822 	}
823 	list_for_each_entry(lprops, &c->freeable_list, list) {
824 		c->lsave[cnt++] = lprops->lnum;
825 		if (cnt >= c->lsave_cnt)
826 			return;
827 	}
828 	list_for_each_entry(lprops, &c->frdi_idx_list, list) {
829 		c->lsave[cnt++] = lprops->lnum;
830 		if (cnt >= c->lsave_cnt)
831 			return;
832 	}
833 	heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
834 	for (i = 0; i < heap->cnt; i++) {
835 		c->lsave[cnt++] = heap->arr[i]->lnum;
836 		if (cnt >= c->lsave_cnt)
837 			return;
838 	}
839 	heap = &c->lpt_heap[LPROPS_DIRTY - 1];
840 	for (i = 0; i < heap->cnt; i++) {
841 		c->lsave[cnt++] = heap->arr[i]->lnum;
842 		if (cnt >= c->lsave_cnt)
843 			return;
844 	}
845 	heap = &c->lpt_heap[LPROPS_FREE - 1];
846 	for (i = 0; i < heap->cnt; i++) {
847 		c->lsave[cnt++] = heap->arr[i]->lnum;
848 		if (cnt >= c->lsave_cnt)
849 			return;
850 	}
851 	/* Fill it up completely */
852 	while (cnt < c->lsave_cnt)
853 		c->lsave[cnt++] = c->main_first;
854 }
855 
856 /**
857  * nnode_lookup - lookup a nnode in the LPT.
858  * @c: UBIFS file-system description object
859  * @i: nnode number
860  *
861  * This function returns a pointer to the nnode on success or a negative
862  * error code on failure.
863  */
864 static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i)
865 {
866 	int err, iip;
867 	struct ubifs_nnode *nnode;
868 
869 	if (!c->nroot) {
870 		err = ubifs_read_nnode(c, NULL, 0);
871 		if (err)
872 			return ERR_PTR(err);
873 	}
874 	nnode = c->nroot;
875 	while (1) {
876 		iip = i & (UBIFS_LPT_FANOUT - 1);
877 		i >>= UBIFS_LPT_FANOUT_SHIFT;
878 		if (!i)
879 			break;
880 		nnode = ubifs_get_nnode(c, nnode, iip);
881 		if (IS_ERR(nnode))
882 			return nnode;
883 	}
884 	return nnode;
885 }
886 
887 /**
888  * make_nnode_dirty - find a nnode and, if found, make it dirty.
889  * @c: UBIFS file-system description object
890  * @node_num: nnode number of nnode to make dirty
891  * @lnum: LEB number where nnode was written
892  * @offs: offset where nnode was written
893  *
894  * This function is used by LPT garbage collection.  LPT garbage collection is
895  * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
896  * simply involves marking all the nodes in the LEB being garbage-collected as
897  * dirty.  The dirty nodes are written next commit, after which the LEB is free
898  * to be reused.
899  *
900  * This function returns %0 on success and a negative error code on failure.
901  */
902 static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum,
903 			    int offs)
904 {
905 	struct ubifs_nnode *nnode;
906 
907 	nnode = nnode_lookup(c, node_num);
908 	if (IS_ERR(nnode))
909 		return PTR_ERR(nnode);
910 	if (nnode->parent) {
911 		struct ubifs_nbranch *branch;
912 
913 		branch = &nnode->parent->nbranch[nnode->iip];
914 		if (branch->lnum != lnum || branch->offs != offs)
915 			return 0; /* nnode is obsolete */
916 	} else if (c->lpt_lnum != lnum || c->lpt_offs != offs)
917 			return 0; /* nnode is obsolete */
918 	/* Assumes cnext list is empty i.e. not called during commit */
919 	if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
920 		c->dirty_nn_cnt += 1;
921 		ubifs_add_nnode_dirt(c, nnode);
922 		/* Mark parent and ancestors dirty too */
923 		nnode = nnode->parent;
924 		while (nnode) {
925 			if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
926 				c->dirty_nn_cnt += 1;
927 				ubifs_add_nnode_dirt(c, nnode);
928 				nnode = nnode->parent;
929 			} else
930 				break;
931 		}
932 	}
933 	return 0;
934 }
935 
936 /**
937  * make_pnode_dirty - find a pnode and, if found, make it dirty.
938  * @c: UBIFS file-system description object
939  * @node_num: pnode number of pnode to make dirty
940  * @lnum: LEB number where pnode was written
941  * @offs: offset where pnode was written
942  *
943  * This function is used by LPT garbage collection.  LPT garbage collection is
944  * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
945  * simply involves marking all the nodes in the LEB being garbage-collected as
946  * dirty.  The dirty nodes are written next commit, after which the LEB is free
947  * to be reused.
948  *
949  * This function returns %0 on success and a negative error code on failure.
950  */
951 static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum,
952 			    int offs)
953 {
954 	struct ubifs_pnode *pnode;
955 	struct ubifs_nbranch *branch;
956 
957 	pnode = pnode_lookup(c, node_num);
958 	if (IS_ERR(pnode))
959 		return PTR_ERR(pnode);
960 	branch = &pnode->parent->nbranch[pnode->iip];
961 	if (branch->lnum != lnum || branch->offs != offs)
962 		return 0;
963 	do_make_pnode_dirty(c, pnode);
964 	return 0;
965 }
966 
967 /**
968  * make_ltab_dirty - make ltab node dirty.
969  * @c: UBIFS file-system description object
970  * @lnum: LEB number where ltab was written
971  * @offs: offset where ltab was written
972  *
973  * This function is used by LPT garbage collection.  LPT garbage collection is
974  * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
975  * simply involves marking all the nodes in the LEB being garbage-collected as
976  * dirty.  The dirty nodes are written next commit, after which the LEB is free
977  * to be reused.
978  *
979  * This function returns %0 on success and a negative error code on failure.
980  */
981 static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
982 {
983 	if (lnum != c->ltab_lnum || offs != c->ltab_offs)
984 		return 0; /* This ltab node is obsolete */
985 	if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
986 		c->lpt_drty_flgs |= LTAB_DIRTY;
987 		ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
988 	}
989 	return 0;
990 }
991 
992 /**
993  * make_lsave_dirty - make lsave node dirty.
994  * @c: UBIFS file-system description object
995  * @lnum: LEB number where lsave was written
996  * @offs: offset where lsave was written
997  *
998  * This function is used by LPT garbage collection.  LPT garbage collection is
999  * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
1000  * simply involves marking all the nodes in the LEB being garbage-collected as
1001  * dirty.  The dirty nodes are written next commit, after which the LEB is free
1002  * to be reused.
1003  *
1004  * This function returns %0 on success and a negative error code on failure.
1005  */
1006 static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
1007 {
1008 	if (lnum != c->lsave_lnum || offs != c->lsave_offs)
1009 		return 0; /* This lsave node is obsolete */
1010 	if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
1011 		c->lpt_drty_flgs |= LSAVE_DIRTY;
1012 		ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
1013 	}
1014 	return 0;
1015 }
1016 
1017 /**
1018  * make_node_dirty - make node dirty.
1019  * @c: UBIFS file-system description object
1020  * @node_type: LPT node type
1021  * @node_num: node number
1022  * @lnum: LEB number where node was written
1023  * @offs: offset where node was written
1024  *
1025  * This function is used by LPT garbage collection.  LPT garbage collection is
1026  * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
1027  * simply involves marking all the nodes in the LEB being garbage-collected as
1028  * dirty.  The dirty nodes are written next commit, after which the LEB is free
1029  * to be reused.
1030  *
1031  * This function returns %0 on success and a negative error code on failure.
1032  */
1033 static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num,
1034 			   int lnum, int offs)
1035 {
1036 	switch (node_type) {
1037 	case UBIFS_LPT_NNODE:
1038 		return make_nnode_dirty(c, node_num, lnum, offs);
1039 	case UBIFS_LPT_PNODE:
1040 		return make_pnode_dirty(c, node_num, lnum, offs);
1041 	case UBIFS_LPT_LTAB:
1042 		return make_ltab_dirty(c, lnum, offs);
1043 	case UBIFS_LPT_LSAVE:
1044 		return make_lsave_dirty(c, lnum, offs);
1045 	}
1046 	return -EINVAL;
1047 }
1048 
1049 /**
1050  * get_lpt_node_len - return the length of a node based on its type.
1051  * @c: UBIFS file-system description object
1052  * @node_type: LPT node type
1053  */
1054 static int get_lpt_node_len(const struct ubifs_info *c, int node_type)
1055 {
1056 	switch (node_type) {
1057 	case UBIFS_LPT_NNODE:
1058 		return c->nnode_sz;
1059 	case UBIFS_LPT_PNODE:
1060 		return c->pnode_sz;
1061 	case UBIFS_LPT_LTAB:
1062 		return c->ltab_sz;
1063 	case UBIFS_LPT_LSAVE:
1064 		return c->lsave_sz;
1065 	}
1066 	return 0;
1067 }
1068 
1069 /**
1070  * get_pad_len - return the length of padding in a buffer.
1071  * @c: UBIFS file-system description object
1072  * @buf: buffer
1073  * @len: length of buffer
1074  */
1075 static int get_pad_len(const struct ubifs_info *c, uint8_t *buf, int len)
1076 {
1077 	int offs, pad_len;
1078 
1079 	if (c->min_io_size == 1)
1080 		return 0;
1081 	offs = c->leb_size - len;
1082 	pad_len = ALIGN(offs, c->min_io_size) - offs;
1083 	return pad_len;
1084 }
1085 
1086 /**
1087  * get_lpt_node_type - return type (and node number) of a node in a buffer.
1088  * @c: UBIFS file-system description object
1089  * @buf: buffer
1090  * @node_num: node number is returned here
1091  */
1092 static int get_lpt_node_type(const struct ubifs_info *c, uint8_t *buf,
1093 			     int *node_num)
1094 {
1095 	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1096 	int pos = 0, node_type;
1097 
1098 	node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
1099 	*node_num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
1100 	return node_type;
1101 }
1102 
1103 /**
1104  * is_a_node - determine if a buffer contains a node.
1105  * @c: UBIFS file-system description object
1106  * @buf: buffer
1107  * @len: length of buffer
1108  *
1109  * This function returns %1 if the buffer contains a node or %0 if it does not.
1110  */
1111 static int is_a_node(const struct ubifs_info *c, uint8_t *buf, int len)
1112 {
1113 	uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1114 	int pos = 0, node_type, node_len;
1115 	uint16_t crc, calc_crc;
1116 
1117 	if (len < UBIFS_LPT_CRC_BYTES + (UBIFS_LPT_TYPE_BITS + 7) / 8)
1118 		return 0;
1119 	node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
1120 	if (node_type == UBIFS_LPT_NOT_A_NODE)
1121 		return 0;
1122 	node_len = get_lpt_node_len(c, node_type);
1123 	if (!node_len || node_len > len)
1124 		return 0;
1125 	pos = 0;
1126 	addr = buf;
1127 	crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
1128 	calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
1129 			 node_len - UBIFS_LPT_CRC_BYTES);
1130 	if (crc != calc_crc)
1131 		return 0;
1132 	return 1;
1133 }
1134 
1135 /**
1136  * lpt_gc_lnum - garbage collect a LPT LEB.
1137  * @c: UBIFS file-system description object
1138  * @lnum: LEB number to garbage collect
1139  *
1140  * LPT garbage collection is used only for the "big" LPT model
1141  * (c->big_lpt == 1).  Garbage collection simply involves marking all the nodes
1142  * in the LEB being garbage-collected as dirty.  The dirty nodes are written
1143  * next commit, after which the LEB is free to be reused.
1144  *
1145  * This function returns %0 on success and a negative error code on failure.
1146  */
1147 static int lpt_gc_lnum(struct ubifs_info *c, int lnum)
1148 {
1149 	int err, len = c->leb_size, node_type, node_num, node_len, offs;
1150 	void *buf = c->lpt_buf;
1151 
1152 	dbg_lp("LEB %d", lnum);
1153 	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
1154 	if (err) {
1155 		ubifs_err("cannot read LEB %d, error %d", lnum, err);
1156 		return err;
1157 	}
1158 	while (1) {
1159 		if (!is_a_node(c, buf, len)) {
1160 			int pad_len;
1161 
1162 			pad_len = get_pad_len(c, buf, len);
1163 			if (pad_len) {
1164 				buf += pad_len;
1165 				len -= pad_len;
1166 				continue;
1167 			}
1168 			return 0;
1169 		}
1170 		node_type = get_lpt_node_type(c, buf, &node_num);
1171 		node_len = get_lpt_node_len(c, node_type);
1172 		offs = c->leb_size - len;
1173 		ubifs_assert(node_len != 0);
1174 		mutex_lock(&c->lp_mutex);
1175 		err = make_node_dirty(c, node_type, node_num, lnum, offs);
1176 		mutex_unlock(&c->lp_mutex);
1177 		if (err)
1178 			return err;
1179 		buf += node_len;
1180 		len -= node_len;
1181 	}
1182 	return 0;
1183 }
1184 
1185 /**
1186  * lpt_gc - LPT garbage collection.
1187  * @c: UBIFS file-system description object
1188  *
1189  * Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'.
1190  * Returns %0 on success and a negative error code on failure.
1191  */
1192 static int lpt_gc(struct ubifs_info *c)
1193 {
1194 	int i, lnum = -1, dirty = 0;
1195 
1196 	mutex_lock(&c->lp_mutex);
1197 	for (i = 0; i < c->lpt_lebs; i++) {
1198 		ubifs_assert(!c->ltab[i].tgc);
1199 		if (i + c->lpt_first == c->nhead_lnum ||
1200 		    c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
1201 			continue;
1202 		if (c->ltab[i].dirty > dirty) {
1203 			dirty = c->ltab[i].dirty;
1204 			lnum = i + c->lpt_first;
1205 		}
1206 	}
1207 	mutex_unlock(&c->lp_mutex);
1208 	if (lnum == -1)
1209 		return -ENOSPC;
1210 	return lpt_gc_lnum(c, lnum);
1211 }
1212 
1213 /**
1214  * ubifs_lpt_start_commit - UBIFS commit starts.
1215  * @c: the UBIFS file-system description object
1216  *
1217  * This function has to be called when UBIFS starts the commit operation.
1218  * This function "freezes" all currently dirty LEB properties and does not
1219  * change them anymore. Further changes are saved and tracked separately
1220  * because they are not part of this commit. This function returns zero in case
1221  * of success and a negative error code in case of failure.
1222  */
1223 int ubifs_lpt_start_commit(struct ubifs_info *c)
1224 {
1225 	int err, cnt;
1226 
1227 	dbg_lp("");
1228 
1229 	mutex_lock(&c->lp_mutex);
1230 	err = dbg_chk_lpt_free_spc(c);
1231 	if (err)
1232 		goto out;
1233 	err = dbg_check_ltab(c);
1234 	if (err)
1235 		goto out;
1236 
1237 	if (c->check_lpt_free) {
1238 		/*
1239 		 * We ensure there is enough free space in
1240 		 * ubifs_lpt_post_commit() by marking nodes dirty. That
1241 		 * information is lost when we unmount, so we also need
1242 		 * to check free space once after mounting also.
1243 		 */
1244 		c->check_lpt_free = 0;
1245 		while (need_write_all(c)) {
1246 			mutex_unlock(&c->lp_mutex);
1247 			err = lpt_gc(c);
1248 			if (err)
1249 				return err;
1250 			mutex_lock(&c->lp_mutex);
1251 		}
1252 	}
1253 
1254 	lpt_tgc_start(c);
1255 
1256 	if (!c->dirty_pn_cnt) {
1257 		dbg_cmt("no cnodes to commit");
1258 		err = 0;
1259 		goto out;
1260 	}
1261 
1262 	if (!c->big_lpt && need_write_all(c)) {
1263 		/* If needed, write everything */
1264 		err = make_tree_dirty(c);
1265 		if (err)
1266 			goto out;
1267 		lpt_tgc_start(c);
1268 	}
1269 
1270 	if (c->big_lpt)
1271 		populate_lsave(c);
1272 
1273 	cnt = get_cnodes_to_commit(c);
1274 	ubifs_assert(cnt != 0);
1275 
1276 	err = layout_cnodes(c);
1277 	if (err)
1278 		goto out;
1279 
1280 	/* Copy the LPT's own lprops for end commit to write */
1281 	memcpy(c->ltab_cmt, c->ltab,
1282 	       sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1283 	c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY);
1284 
1285 out:
1286 	mutex_unlock(&c->lp_mutex);
1287 	return err;
1288 }
1289 
1290 /**
1291  * free_obsolete_cnodes - free obsolete cnodes for commit end.
1292  * @c: UBIFS file-system description object
1293  */
1294 static void free_obsolete_cnodes(struct ubifs_info *c)
1295 {
1296 	struct ubifs_cnode *cnode, *cnext;
1297 
1298 	cnext = c->lpt_cnext;
1299 	if (!cnext)
1300 		return;
1301 	do {
1302 		cnode = cnext;
1303 		cnext = cnode->cnext;
1304 		if (test_bit(OBSOLETE_CNODE, &cnode->flags))
1305 			kfree(cnode);
1306 		else
1307 			cnode->cnext = NULL;
1308 	} while (cnext != c->lpt_cnext);
1309 	c->lpt_cnext = NULL;
1310 }
1311 
1312 /**
1313  * ubifs_lpt_end_commit - finish the commit operation.
1314  * @c: the UBIFS file-system description object
1315  *
1316  * This function has to be called when the commit operation finishes. It
1317  * flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to
1318  * the media. Returns zero in case of success and a negative error code in case
1319  * of failure.
1320  */
1321 int ubifs_lpt_end_commit(struct ubifs_info *c)
1322 {
1323 	int err;
1324 
1325 	dbg_lp("");
1326 
1327 	if (!c->lpt_cnext)
1328 		return 0;
1329 
1330 	err = write_cnodes(c);
1331 	if (err)
1332 		return err;
1333 
1334 	mutex_lock(&c->lp_mutex);
1335 	free_obsolete_cnodes(c);
1336 	mutex_unlock(&c->lp_mutex);
1337 
1338 	return 0;
1339 }
1340 
1341 /**
1342  * ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC.
1343  * @c: UBIFS file-system description object
1344  *
1345  * LPT trivial GC is completed after a commit. Also LPT GC is done after a
1346  * commit for the "big" LPT model.
1347  */
1348 int ubifs_lpt_post_commit(struct ubifs_info *c)
1349 {
1350 	int err;
1351 
1352 	mutex_lock(&c->lp_mutex);
1353 	err = lpt_tgc_end(c);
1354 	if (err)
1355 		goto out;
1356 	if (c->big_lpt)
1357 		while (need_write_all(c)) {
1358 			mutex_unlock(&c->lp_mutex);
1359 			err = lpt_gc(c);
1360 			if (err)
1361 				return err;
1362 			mutex_lock(&c->lp_mutex);
1363 		}
1364 out:
1365 	mutex_unlock(&c->lp_mutex);
1366 	return err;
1367 }
1368 
1369 /**
1370  * first_nnode - find the first nnode in memory.
1371  * @c: UBIFS file-system description object
1372  * @hght: height of tree where nnode found is returned here
1373  *
1374  * This function returns a pointer to the nnode found or %NULL if no nnode is
1375  * found. This function is a helper to 'ubifs_lpt_free()'.
1376  */
1377 static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght)
1378 {
1379 	struct ubifs_nnode *nnode;
1380 	int h, i, found;
1381 
1382 	nnode = c->nroot;
1383 	*hght = 0;
1384 	if (!nnode)
1385 		return NULL;
1386 	for (h = 1; h < c->lpt_hght; h++) {
1387 		found = 0;
1388 		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1389 			if (nnode->nbranch[i].nnode) {
1390 				found = 1;
1391 				nnode = nnode->nbranch[i].nnode;
1392 				*hght = h;
1393 				break;
1394 			}
1395 		}
1396 		if (!found)
1397 			break;
1398 	}
1399 	return nnode;
1400 }
1401 
1402 /**
1403  * next_nnode - find the next nnode in memory.
1404  * @c: UBIFS file-system description object
1405  * @nnode: nnode from which to start.
1406  * @hght: height of tree where nnode is, is passed and returned here
1407  *
1408  * This function returns a pointer to the nnode found or %NULL if no nnode is
1409  * found. This function is a helper to 'ubifs_lpt_free()'.
1410  */
1411 static struct ubifs_nnode *next_nnode(struct ubifs_info *c,
1412 				      struct ubifs_nnode *nnode, int *hght)
1413 {
1414 	struct ubifs_nnode *parent;
1415 	int iip, h, i, found;
1416 
1417 	parent = nnode->parent;
1418 	if (!parent)
1419 		return NULL;
1420 	if (nnode->iip == UBIFS_LPT_FANOUT - 1) {
1421 		*hght -= 1;
1422 		return parent;
1423 	}
1424 	for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
1425 		nnode = parent->nbranch[iip].nnode;
1426 		if (nnode)
1427 			break;
1428 	}
1429 	if (!nnode) {
1430 		*hght -= 1;
1431 		return parent;
1432 	}
1433 	for (h = *hght + 1; h < c->lpt_hght; h++) {
1434 		found = 0;
1435 		for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1436 			if (nnode->nbranch[i].nnode) {
1437 				found = 1;
1438 				nnode = nnode->nbranch[i].nnode;
1439 				*hght = h;
1440 				break;
1441 			}
1442 		}
1443 		if (!found)
1444 			break;
1445 	}
1446 	return nnode;
1447 }
1448 
1449 /**
1450  * ubifs_lpt_free - free resources owned by the LPT.
1451  * @c: UBIFS file-system description object
1452  * @wr_only: free only resources used for writing
1453  */
1454 void ubifs_lpt_free(struct ubifs_info *c, int wr_only)
1455 {
1456 	struct ubifs_nnode *nnode;
1457 	int i, hght;
1458 
1459 	/* Free write-only things first */
1460 
1461 	free_obsolete_cnodes(c); /* Leftover from a failed commit */
1462 
1463 	vfree(c->ltab_cmt);
1464 	c->ltab_cmt = NULL;
1465 	vfree(c->lpt_buf);
1466 	c->lpt_buf = NULL;
1467 	kfree(c->lsave);
1468 	c->lsave = NULL;
1469 
1470 	if (wr_only)
1471 		return;
1472 
1473 	/* Now free the rest */
1474 
1475 	nnode = first_nnode(c, &hght);
1476 	while (nnode) {
1477 		for (i = 0; i < UBIFS_LPT_FANOUT; i++)
1478 			kfree(nnode->nbranch[i].nnode);
1479 		nnode = next_nnode(c, nnode, &hght);
1480 	}
1481 	for (i = 0; i < LPROPS_HEAP_CNT; i++)
1482 		kfree(c->lpt_heap[i].arr);
1483 	kfree(c->dirty_idx.arr);
1484 	kfree(c->nroot);
1485 	vfree(c->ltab);
1486 	kfree(c->lpt_nod_buf);
1487 }
1488 
1489 #ifdef CONFIG_UBIFS_FS_DEBUG
1490 
1491 /**
1492  * dbg_is_all_ff - determine if a buffer contains only 0xFF bytes.
1493  * @buf: buffer
1494  * @len: buffer length
1495  */
1496 static int dbg_is_all_ff(uint8_t *buf, int len)
1497 {
1498 	int i;
1499 
1500 	for (i = 0; i < len; i++)
1501 		if (buf[i] != 0xff)
1502 			return 0;
1503 	return 1;
1504 }
1505 
1506 /**
1507  * dbg_is_nnode_dirty - determine if a nnode is dirty.
1508  * @c: the UBIFS file-system description object
1509  * @lnum: LEB number where nnode was written
1510  * @offs: offset where nnode was written
1511  */
1512 static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs)
1513 {
1514 	struct ubifs_nnode *nnode;
1515 	int hght;
1516 
1517 	/* Entire tree is in memory so first_nnode / next_nnode are OK */
1518 	nnode = first_nnode(c, &hght);
1519 	for (; nnode; nnode = next_nnode(c, nnode, &hght)) {
1520 		struct ubifs_nbranch *branch;
1521 
1522 		cond_resched();
1523 		if (nnode->parent) {
1524 			branch = &nnode->parent->nbranch[nnode->iip];
1525 			if (branch->lnum != lnum || branch->offs != offs)
1526 				continue;
1527 			if (test_bit(DIRTY_CNODE, &nnode->flags))
1528 				return 1;
1529 			return 0;
1530 		} else {
1531 			if (c->lpt_lnum != lnum || c->lpt_offs != offs)
1532 				continue;
1533 			if (test_bit(DIRTY_CNODE, &nnode->flags))
1534 				return 1;
1535 			return 0;
1536 		}
1537 	}
1538 	return 1;
1539 }
1540 
1541 /**
1542  * dbg_is_pnode_dirty - determine if a pnode is dirty.
1543  * @c: the UBIFS file-system description object
1544  * @lnum: LEB number where pnode was written
1545  * @offs: offset where pnode was written
1546  */
1547 static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs)
1548 {
1549 	int i, cnt;
1550 
1551 	cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
1552 	for (i = 0; i < cnt; i++) {
1553 		struct ubifs_pnode *pnode;
1554 		struct ubifs_nbranch *branch;
1555 
1556 		cond_resched();
1557 		pnode = pnode_lookup(c, i);
1558 		if (IS_ERR(pnode))
1559 			return PTR_ERR(pnode);
1560 		branch = &pnode->parent->nbranch[pnode->iip];
1561 		if (branch->lnum != lnum || branch->offs != offs)
1562 			continue;
1563 		if (test_bit(DIRTY_CNODE, &pnode->flags))
1564 			return 1;
1565 		return 0;
1566 	}
1567 	return 1;
1568 }
1569 
1570 /**
1571  * dbg_is_ltab_dirty - determine if a ltab node is dirty.
1572  * @c: the UBIFS file-system description object
1573  * @lnum: LEB number where ltab node was written
1574  * @offs: offset where ltab node was written
1575  */
1576 static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
1577 {
1578 	if (lnum != c->ltab_lnum || offs != c->ltab_offs)
1579 		return 1;
1580 	return (c->lpt_drty_flgs & LTAB_DIRTY) != 0;
1581 }
1582 
1583 /**
1584  * dbg_is_lsave_dirty - determine if a lsave node is dirty.
1585  * @c: the UBIFS file-system description object
1586  * @lnum: LEB number where lsave node was written
1587  * @offs: offset where lsave node was written
1588  */
1589 static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
1590 {
1591 	if (lnum != c->lsave_lnum || offs != c->lsave_offs)
1592 		return 1;
1593 	return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0;
1594 }
1595 
1596 /**
1597  * dbg_is_node_dirty - determine if a node is dirty.
1598  * @c: the UBIFS file-system description object
1599  * @node_type: node type
1600  * @lnum: LEB number where node was written
1601  * @offs: offset where node was written
1602  */
1603 static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum,
1604 			     int offs)
1605 {
1606 	switch (node_type) {
1607 	case UBIFS_LPT_NNODE:
1608 		return dbg_is_nnode_dirty(c, lnum, offs);
1609 	case UBIFS_LPT_PNODE:
1610 		return dbg_is_pnode_dirty(c, lnum, offs);
1611 	case UBIFS_LPT_LTAB:
1612 		return dbg_is_ltab_dirty(c, lnum, offs);
1613 	case UBIFS_LPT_LSAVE:
1614 		return dbg_is_lsave_dirty(c, lnum, offs);
1615 	}
1616 	return 1;
1617 }
1618 
1619 /**
1620  * dbg_check_ltab_lnum - check the ltab for a LPT LEB number.
1621  * @c: the UBIFS file-system description object
1622  * @lnum: LEB number where node was written
1623  * @offs: offset where node was written
1624  *
1625  * This function returns %0 on success and a negative error code on failure.
1626  */
1627 static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
1628 {
1629 	int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len;
1630 	int ret;
1631 	void *buf = c->dbg->buf;
1632 
1633 	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
1634 		return 0;
1635 
1636 	dbg_lp("LEB %d", lnum);
1637 	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
1638 	if (err) {
1639 		dbg_msg("ubi_read failed, LEB %d, error %d", lnum, err);
1640 		return err;
1641 	}
1642 	while (1) {
1643 		if (!is_a_node(c, buf, len)) {
1644 			int i, pad_len;
1645 
1646 			pad_len = get_pad_len(c, buf, len);
1647 			if (pad_len) {
1648 				buf += pad_len;
1649 				len -= pad_len;
1650 				dirty += pad_len;
1651 				continue;
1652 			}
1653 			if (!dbg_is_all_ff(buf, len)) {
1654 				dbg_msg("invalid empty space in LEB %d at %d",
1655 					lnum, c->leb_size - len);
1656 				err = -EINVAL;
1657 			}
1658 			i = lnum - c->lpt_first;
1659 			if (len != c->ltab[i].free) {
1660 				dbg_msg("invalid free space in LEB %d "
1661 					"(free %d, expected %d)",
1662 					lnum, len, c->ltab[i].free);
1663 				err = -EINVAL;
1664 			}
1665 			if (dirty != c->ltab[i].dirty) {
1666 				dbg_msg("invalid dirty space in LEB %d "
1667 					"(dirty %d, expected %d)",
1668 					lnum, dirty, c->ltab[i].dirty);
1669 				err = -EINVAL;
1670 			}
1671 			return err;
1672 		}
1673 		node_type = get_lpt_node_type(c, buf, &node_num);
1674 		node_len = get_lpt_node_len(c, node_type);
1675 		ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len);
1676 		if (ret == 1)
1677 			dirty += node_len;
1678 		buf += node_len;
1679 		len -= node_len;
1680 	}
1681 }
1682 
1683 /**
1684  * dbg_check_ltab - check the free and dirty space in the ltab.
1685  * @c: the UBIFS file-system description object
1686  *
1687  * This function returns %0 on success and a negative error code on failure.
1688  */
1689 int dbg_check_ltab(struct ubifs_info *c)
1690 {
1691 	int lnum, err, i, cnt;
1692 
1693 	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
1694 		return 0;
1695 
1696 	/* Bring the entire tree into memory */
1697 	cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
1698 	for (i = 0; i < cnt; i++) {
1699 		struct ubifs_pnode *pnode;
1700 
1701 		pnode = pnode_lookup(c, i);
1702 		if (IS_ERR(pnode))
1703 			return PTR_ERR(pnode);
1704 		cond_resched();
1705 	}
1706 
1707 	/* Check nodes */
1708 	err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)c->nroot, 0, 0);
1709 	if (err)
1710 		return err;
1711 
1712 	/* Check each LEB */
1713 	for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
1714 		err = dbg_check_ltab_lnum(c, lnum);
1715 		if (err) {
1716 			dbg_err("failed at LEB %d", lnum);
1717 			return err;
1718 		}
1719 	}
1720 
1721 	dbg_lp("succeeded");
1722 	return 0;
1723 }
1724 
1725 /**
1726  * dbg_chk_lpt_free_spc - check LPT free space is enough to write entire LPT.
1727  * @c: the UBIFS file-system description object
1728  *
1729  * This function returns %0 on success and a negative error code on failure.
1730  */
1731 int dbg_chk_lpt_free_spc(struct ubifs_info *c)
1732 {
1733 	long long free = 0;
1734 	int i;
1735 
1736 	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
1737 		return 0;
1738 
1739 	for (i = 0; i < c->lpt_lebs; i++) {
1740 		if (c->ltab[i].tgc || c->ltab[i].cmt)
1741 			continue;
1742 		if (i + c->lpt_first == c->nhead_lnum)
1743 			free += c->leb_size - c->nhead_offs;
1744 		else if (c->ltab[i].free == c->leb_size)
1745 			free += c->leb_size;
1746 	}
1747 	if (free < c->lpt_sz) {
1748 		dbg_err("LPT space error: free %lld lpt_sz %lld",
1749 			free, c->lpt_sz);
1750 		dbg_dump_lpt_info(c);
1751 		dbg_dump_lpt_lebs(c);
1752 		dump_stack();
1753 		return -EINVAL;
1754 	}
1755 	return 0;
1756 }
1757 
1758 /**
1759  * dbg_chk_lpt_sz - check LPT does not write more than LPT size.
1760  * @c: the UBIFS file-system description object
1761  * @action: what to do
1762  * @len: length written
1763  *
1764  * This function returns %0 on success and a negative error code on failure.
1765  * The @action argument may be one of:
1766  *   o %0 - LPT debugging checking starts, initialize debugging variables;
1767  *   o %1 - wrote an LPT node, increase LPT size by @len bytes;
1768  *   o %2 - switched to a different LEB and wasted @len bytes;
1769  *   o %3 - check that we've written the right number of bytes.
1770  *   o %4 - wasted @len bytes;
1771  */
1772 int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
1773 {
1774 	struct ubifs_debug_info *d = c->dbg;
1775 	long long chk_lpt_sz, lpt_sz;
1776 	int err = 0;
1777 
1778 	if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
1779 		return 0;
1780 
1781 	switch (action) {
1782 	case 0:
1783 		d->chk_lpt_sz = 0;
1784 		d->chk_lpt_sz2 = 0;
1785 		d->chk_lpt_lebs = 0;
1786 		d->chk_lpt_wastage = 0;
1787 		if (c->dirty_pn_cnt > c->pnode_cnt) {
1788 			dbg_err("dirty pnodes %d exceed max %d",
1789 				c->dirty_pn_cnt, c->pnode_cnt);
1790 			err = -EINVAL;
1791 		}
1792 		if (c->dirty_nn_cnt > c->nnode_cnt) {
1793 			dbg_err("dirty nnodes %d exceed max %d",
1794 				c->dirty_nn_cnt, c->nnode_cnt);
1795 			err = -EINVAL;
1796 		}
1797 		return err;
1798 	case 1:
1799 		d->chk_lpt_sz += len;
1800 		return 0;
1801 	case 2:
1802 		d->chk_lpt_sz += len;
1803 		d->chk_lpt_wastage += len;
1804 		d->chk_lpt_lebs += 1;
1805 		return 0;
1806 	case 3:
1807 		chk_lpt_sz = c->leb_size;
1808 		chk_lpt_sz *= d->chk_lpt_lebs;
1809 		chk_lpt_sz += len - c->nhead_offs;
1810 		if (d->chk_lpt_sz != chk_lpt_sz) {
1811 			dbg_err("LPT wrote %lld but space used was %lld",
1812 				d->chk_lpt_sz, chk_lpt_sz);
1813 			err = -EINVAL;
1814 		}
1815 		if (d->chk_lpt_sz > c->lpt_sz) {
1816 			dbg_err("LPT wrote %lld but lpt_sz is %lld",
1817 				d->chk_lpt_sz, c->lpt_sz);
1818 			err = -EINVAL;
1819 		}
1820 		if (d->chk_lpt_sz2 && d->chk_lpt_sz != d->chk_lpt_sz2) {
1821 			dbg_err("LPT layout size %lld but wrote %lld",
1822 				d->chk_lpt_sz, d->chk_lpt_sz2);
1823 			err = -EINVAL;
1824 		}
1825 		if (d->chk_lpt_sz2 && d->new_nhead_offs != len) {
1826 			dbg_err("LPT new nhead offs: expected %d was %d",
1827 				d->new_nhead_offs, len);
1828 			err = -EINVAL;
1829 		}
1830 		lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
1831 		lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
1832 		lpt_sz += c->ltab_sz;
1833 		if (c->big_lpt)
1834 			lpt_sz += c->lsave_sz;
1835 		if (d->chk_lpt_sz - d->chk_lpt_wastage > lpt_sz) {
1836 			dbg_err("LPT chk_lpt_sz %lld + waste %lld exceeds %lld",
1837 				d->chk_lpt_sz, d->chk_lpt_wastage, lpt_sz);
1838 			err = -EINVAL;
1839 		}
1840 		if (err) {
1841 			dbg_dump_lpt_info(c);
1842 			dbg_dump_lpt_lebs(c);
1843 			dump_stack();
1844 		}
1845 		d->chk_lpt_sz2 = d->chk_lpt_sz;
1846 		d->chk_lpt_sz = 0;
1847 		d->chk_lpt_wastage = 0;
1848 		d->chk_lpt_lebs = 0;
1849 		d->new_nhead_offs = len;
1850 		return err;
1851 	case 4:
1852 		d->chk_lpt_sz += len;
1853 		d->chk_lpt_wastage += len;
1854 		return 0;
1855 	default:
1856 		return -EINVAL;
1857 	}
1858 }
1859 
1860 /**
1861  * dbg_dump_lpt_leb - dump an LPT LEB.
1862  * @c: UBIFS file-system description object
1863  * @lnum: LEB number to dump
1864  *
1865  * This function dumps an LEB from LPT area. Nodes in this area are very
1866  * different to nodes in the main area (e.g., they do not have common headers,
1867  * they do not have 8-byte alignments, etc), so we have a separate function to
1868  * dump LPT area LEBs. Note, LPT has to be locked by the caller.
1869  */
1870 static void dump_lpt_leb(const struct ubifs_info *c, int lnum)
1871 {
1872 	int err, len = c->leb_size, node_type, node_num, node_len, offs;
1873 	void *buf = c->dbg->buf;
1874 
1875 	printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
1876 	       current->pid, lnum);
1877 	err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
1878 	if (err) {
1879 		ubifs_err("cannot read LEB %d, error %d", lnum, err);
1880 		return;
1881 	}
1882 	while (1) {
1883 		offs = c->leb_size - len;
1884 		if (!is_a_node(c, buf, len)) {
1885 			int pad_len;
1886 
1887 			pad_len = get_pad_len(c, buf, len);
1888 			if (pad_len) {
1889 				printk(KERN_DEBUG "LEB %d:%d, pad %d bytes\n",
1890 				       lnum, offs, pad_len);
1891 				buf += pad_len;
1892 				len -= pad_len;
1893 				continue;
1894 			}
1895 			if (len)
1896 				printk(KERN_DEBUG "LEB %d:%d, free %d bytes\n",
1897 				       lnum, offs, len);
1898 			break;
1899 		}
1900 
1901 		node_type = get_lpt_node_type(c, buf, &node_num);
1902 		switch (node_type) {
1903 		case UBIFS_LPT_PNODE:
1904 		{
1905 			node_len = c->pnode_sz;
1906 			if (c->big_lpt)
1907 				printk(KERN_DEBUG "LEB %d:%d, pnode num %d\n",
1908 				       lnum, offs, node_num);
1909 			else
1910 				printk(KERN_DEBUG "LEB %d:%d, pnode\n",
1911 				       lnum, offs);
1912 			break;
1913 		}
1914 		case UBIFS_LPT_NNODE:
1915 		{
1916 			int i;
1917 			struct ubifs_nnode nnode;
1918 
1919 			node_len = c->nnode_sz;
1920 			if (c->big_lpt)
1921 				printk(KERN_DEBUG "LEB %d:%d, nnode num %d, ",
1922 				       lnum, offs, node_num);
1923 			else
1924 				printk(KERN_DEBUG "LEB %d:%d, nnode, ",
1925 				       lnum, offs);
1926 			err = ubifs_unpack_nnode(c, buf, &nnode);
1927 			for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1928 				printk(KERN_CONT "%d:%d", nnode.nbranch[i].lnum,
1929 				       nnode.nbranch[i].offs);
1930 				if (i != UBIFS_LPT_FANOUT - 1)
1931 					printk(KERN_CONT ", ");
1932 			}
1933 			printk(KERN_CONT "\n");
1934 			break;
1935 		}
1936 		case UBIFS_LPT_LTAB:
1937 			node_len = c->ltab_sz;
1938 			printk(KERN_DEBUG "LEB %d:%d, ltab\n",
1939 			       lnum, offs);
1940 			break;
1941 		case UBIFS_LPT_LSAVE:
1942 			node_len = c->lsave_sz;
1943 			printk(KERN_DEBUG "LEB %d:%d, lsave len\n", lnum, offs);
1944 			break;
1945 		default:
1946 			ubifs_err("LPT node type %d not recognized", node_type);
1947 			return;
1948 		}
1949 
1950 		buf += node_len;
1951 		len -= node_len;
1952 	}
1953 
1954 	printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
1955 	       current->pid, lnum);
1956 }
1957 
1958 /**
1959  * dbg_dump_lpt_lebs - dump LPT lebs.
1960  * @c: UBIFS file-system description object
1961  *
1962  * This function dumps all LPT LEBs. The caller has to make sure the LPT is
1963  * locked.
1964  */
1965 void dbg_dump_lpt_lebs(const struct ubifs_info *c)
1966 {
1967 	int i;
1968 
1969 	printk(KERN_DEBUG "(pid %d) start dumping all LPT LEBs\n",
1970 	       current->pid);
1971 	for (i = 0; i < c->lpt_lebs; i++)
1972 		dump_lpt_leb(c, i + c->lpt_first);
1973 	printk(KERN_DEBUG "(pid %d) finish dumping all LPT LEBs\n",
1974 	       current->pid);
1975 }
1976 
1977 #endif /* CONFIG_UBIFS_FS_DEBUG */
1978