xref: /openbmc/u-boot/fs/ubifs/ubifs.c (revision 93322749)
1 /*
2  * This file is part of UBIFS.
3  *
4  * Copyright (C) 2006-2008 Nokia Corporation.
5  *
6  * (C) Copyright 2008-2010
7  * Stefan Roese, DENX Software Engineering, sr@denx.de.
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published by
11  * the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but WITHOUT
14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16  * more details.
17  *
18  * You should have received a copy of the GNU General Public License along with
19  * this program; if not, write to the Free Software Foundation, Inc., 51
20  * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21  *
22  * Authors: Artem Bityutskiy (Битюцкий Артём)
23  *          Adrian Hunter
24  */
25 
26 #include "ubifs.h"
27 #include <u-boot/zlib.h>
28 
29 #include <linux/err.h>
30 #include <linux/lzo.h>
31 
32 DECLARE_GLOBAL_DATA_PTR;
33 
34 /* compress.c */
35 
36 /*
37  * We need a wrapper for zunzip() because the parameters are
38  * incompatible with the lzo decompressor.
39  */
40 static int gzip_decompress(const unsigned char *in, size_t in_len,
41 			   unsigned char *out, size_t *out_len)
42 {
43 	return zunzip(out, *out_len, (unsigned char *)in,
44 		      (unsigned long *)out_len, 0, 0);
45 }
46 
47 /* Fake description object for the "none" compressor */
48 static struct ubifs_compressor none_compr = {
49 	.compr_type = UBIFS_COMPR_NONE,
50 	.name = "none",
51 	.capi_name = "",
52 	.decompress = NULL,
53 };
54 
55 static struct ubifs_compressor lzo_compr = {
56 	.compr_type = UBIFS_COMPR_LZO,
57 #ifndef __UBOOT__
58 	.comp_mutex = &lzo_mutex,
59 #endif
60 	.name = "lzo",
61 	.capi_name = "lzo",
62 	.decompress = lzo1x_decompress_safe,
63 };
64 
65 static struct ubifs_compressor zlib_compr = {
66 	.compr_type = UBIFS_COMPR_ZLIB,
67 #ifndef __UBOOT__
68 	.comp_mutex = &deflate_mutex,
69 	.decomp_mutex = &inflate_mutex,
70 #endif
71 	.name = "zlib",
72 	.capi_name = "deflate",
73 	.decompress = gzip_decompress,
74 };
75 
76 /* All UBIFS compressors */
77 struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
78 
79 
80 #ifdef __UBOOT__
81 /* from mm/util.c */
82 
83 /**
84  * kmemdup - duplicate region of memory
85  *
86  * @src: memory region to duplicate
87  * @len: memory region length
88  * @gfp: GFP mask to use
89  */
90 void *kmemdup(const void *src, size_t len, gfp_t gfp)
91 {
92 	void *p;
93 
94 	p = kmalloc(len, gfp);
95 	if (p)
96 		memcpy(p, src, len);
97 	return p;
98 }
99 
100 struct crypto_comp {
101 	int compressor;
102 };
103 
104 static inline struct crypto_comp *crypto_alloc_comp(const char *alg_name,
105 						u32 type, u32 mask)
106 {
107 	struct ubifs_compressor *comp;
108 	struct crypto_comp *ptr;
109 	int i = 0;
110 
111 	ptr = malloc(sizeof(struct crypto_comp));
112 	while (i < UBIFS_COMPR_TYPES_CNT) {
113 		comp = ubifs_compressors[i];
114 		if (!comp) {
115 			i++;
116 			continue;
117 		}
118 		if (strncmp(alg_name, comp->capi_name, strlen(alg_name)) == 0) {
119 			ptr->compressor = i;
120 			return ptr;
121 		}
122 		i++;
123 	}
124 	if (i >= UBIFS_COMPR_TYPES_CNT) {
125 		ubifs_err("invalid compression type %s", alg_name);
126 		free (ptr);
127 		return NULL;
128 	}
129 	return ptr;
130 }
131 static inline int crypto_comp_decompress(struct crypto_comp *tfm,
132 				const u8 *src, unsigned int slen,
133 				u8 *dst, unsigned int *dlen)
134 {
135 	struct ubifs_compressor *compr = ubifs_compressors[tfm->compressor];
136 	int err;
137 
138 	if (compr->compr_type == UBIFS_COMPR_NONE) {
139 		memcpy(dst, src, slen);
140 		*dlen = slen;
141 		return 0;
142 	}
143 
144 	err = compr->decompress(src, slen, dst, (size_t *)dlen);
145 	if (err)
146 		ubifs_err("cannot decompress %d bytes, compressor %s, "
147 			  "error %d", slen, compr->name, err);
148 
149 	return err;
150 
151 	return 0;
152 }
153 #endif
154 
155 /**
156  * ubifs_decompress - decompress data.
157  * @in_buf: data to decompress
158  * @in_len: length of the data to decompress
159  * @out_buf: output buffer where decompressed data should
160  * @out_len: output length is returned here
161  * @compr_type: type of compression
162  *
163  * This function decompresses data from buffer @in_buf into buffer @out_buf.
164  * The length of the uncompressed data is returned in @out_len. This functions
165  * returns %0 on success or a negative error code on failure.
166  */
167 int ubifs_decompress(const void *in_buf, int in_len, void *out_buf,
168 		     int *out_len, int compr_type)
169 {
170 	int err;
171 	struct ubifs_compressor *compr;
172 
173 	if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) {
174 		ubifs_err("invalid compression type %d", compr_type);
175 		return -EINVAL;
176 	}
177 
178 	compr = ubifs_compressors[compr_type];
179 
180 	if (unlikely(!compr->capi_name)) {
181 		ubifs_err("%s compression is not compiled in", compr->name);
182 		return -EINVAL;
183 	}
184 
185 	if (compr_type == UBIFS_COMPR_NONE) {
186 		memcpy(out_buf, in_buf, in_len);
187 		*out_len = in_len;
188 		return 0;
189 	}
190 
191 	if (compr->decomp_mutex)
192 		mutex_lock(compr->decomp_mutex);
193 	err = crypto_comp_decompress(compr->cc, in_buf, in_len, out_buf,
194 				     (unsigned int *)out_len);
195 	if (compr->decomp_mutex)
196 		mutex_unlock(compr->decomp_mutex);
197 	if (err)
198 		ubifs_err("cannot decompress %d bytes, compressor %s, error %d",
199 			  in_len, compr->name, err);
200 
201 	return err;
202 }
203 
204 /**
205  * compr_init - initialize a compressor.
206  * @compr: compressor description object
207  *
208  * This function initializes the requested compressor and returns zero in case
209  * of success or a negative error code in case of failure.
210  */
211 static int __init compr_init(struct ubifs_compressor *compr)
212 {
213 	ubifs_compressors[compr->compr_type] = compr;
214 
215 #ifdef CONFIG_NEEDS_MANUAL_RELOC
216 	ubifs_compressors[compr->compr_type]->name += gd->reloc_off;
217 	ubifs_compressors[compr->compr_type]->capi_name += gd->reloc_off;
218 	ubifs_compressors[compr->compr_type]->decompress += gd->reloc_off;
219 #endif
220 
221 	if (compr->capi_name) {
222 		compr->cc = crypto_alloc_comp(compr->capi_name, 0, 0);
223 		if (IS_ERR(compr->cc)) {
224 			ubifs_err("cannot initialize compressor %s, error %ld",
225 				  compr->name, PTR_ERR(compr->cc));
226 			return PTR_ERR(compr->cc);
227 		}
228 	}
229 
230 	return 0;
231 }
232 
233 /**
234  * ubifs_compressors_init - initialize UBIFS compressors.
235  *
236  * This function initializes the compressor which were compiled in. Returns
237  * zero in case of success and a negative error code in case of failure.
238  */
239 int __init ubifs_compressors_init(void)
240 {
241 	int err;
242 
243 	err = compr_init(&lzo_compr);
244 	if (err)
245 		return err;
246 
247 	err = compr_init(&zlib_compr);
248 	if (err)
249 		return err;
250 
251 	err = compr_init(&none_compr);
252 	if (err)
253 		return err;
254 
255 	return 0;
256 }
257 
258 /*
259  * ubifsls...
260  */
261 
262 static int filldir(struct ubifs_info *c, const char *name, int namlen,
263 		   u64 ino, unsigned int d_type)
264 {
265 	struct inode *inode;
266 	char filetime[32];
267 
268 	switch (d_type) {
269 	case UBIFS_ITYPE_REG:
270 		printf("\t");
271 		break;
272 	case UBIFS_ITYPE_DIR:
273 		printf("<DIR>\t");
274 		break;
275 	case UBIFS_ITYPE_LNK:
276 		printf("<LNK>\t");
277 		break;
278 	default:
279 		printf("other\t");
280 		break;
281 	}
282 
283 	inode = ubifs_iget(c->vfs_sb, ino);
284 	if (IS_ERR(inode)) {
285 		printf("%s: Error in ubifs_iget(), ino=%lld ret=%p!\n",
286 		       __func__, ino, inode);
287 		return -1;
288 	}
289 	ctime_r((time_t *)&inode->i_mtime, filetime);
290 	printf("%9lld  %24.24s  ", inode->i_size, filetime);
291 #ifndef __UBOOT__
292 	ubifs_iput(inode);
293 #endif
294 
295 	printf("%s\n", name);
296 
297 	return 0;
298 }
299 
300 static int ubifs_printdir(struct file *file, void *dirent)
301 {
302 	int err, over = 0;
303 	struct qstr nm;
304 	union ubifs_key key;
305 	struct ubifs_dent_node *dent;
306 	struct inode *dir = file->f_path.dentry->d_inode;
307 	struct ubifs_info *c = dir->i_sb->s_fs_info;
308 
309 	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
310 
311 	if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
312 		/*
313 		 * The directory was seek'ed to a senseless position or there
314 		 * are no more entries.
315 		 */
316 		return 0;
317 
318 	if (file->f_pos == 1) {
319 		/* Find the first entry in TNC and save it */
320 		lowest_dent_key(c, &key, dir->i_ino);
321 		nm.name = NULL;
322 		dent = ubifs_tnc_next_ent(c, &key, &nm);
323 		if (IS_ERR(dent)) {
324 			err = PTR_ERR(dent);
325 			goto out;
326 		}
327 
328 		file->f_pos = key_hash_flash(c, &dent->key);
329 		file->private_data = dent;
330 	}
331 
332 	dent = file->private_data;
333 	if (!dent) {
334 		/*
335 		 * The directory was seek'ed to and is now readdir'ed.
336 		 * Find the entry corresponding to @file->f_pos or the
337 		 * closest one.
338 		 */
339 		dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
340 		nm.name = NULL;
341 		dent = ubifs_tnc_next_ent(c, &key, &nm);
342 		if (IS_ERR(dent)) {
343 			err = PTR_ERR(dent);
344 			goto out;
345 		}
346 		file->f_pos = key_hash_flash(c, &dent->key);
347 		file->private_data = dent;
348 	}
349 
350 	while (1) {
351 		dbg_gen("feed '%s', ino %llu, new f_pos %#x",
352 			dent->name, (unsigned long long)le64_to_cpu(dent->inum),
353 			key_hash_flash(c, &dent->key));
354 		ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum);
355 
356 		nm.len = le16_to_cpu(dent->nlen);
357 		over = filldir(c, (char *)dent->name, nm.len,
358 			       le64_to_cpu(dent->inum), dent->type);
359 		if (over)
360 			return 0;
361 
362 		/* Switch to the next entry */
363 		key_read(c, &dent->key, &key);
364 		nm.name = (char *)dent->name;
365 		dent = ubifs_tnc_next_ent(c, &key, &nm);
366 		if (IS_ERR(dent)) {
367 			err = PTR_ERR(dent);
368 			goto out;
369 		}
370 
371 		kfree(file->private_data);
372 		file->f_pos = key_hash_flash(c, &dent->key);
373 		file->private_data = dent;
374 		cond_resched();
375 	}
376 
377 out:
378 	if (err != -ENOENT) {
379 		ubifs_err("cannot find next direntry, error %d", err);
380 		return err;
381 	}
382 
383 	kfree(file->private_data);
384 	file->private_data = NULL;
385 	file->f_pos = 2;
386 	return 0;
387 }
388 
389 static int ubifs_finddir(struct super_block *sb, char *dirname,
390 			 unsigned long root_inum, unsigned long *inum)
391 {
392 	int err;
393 	struct qstr nm;
394 	union ubifs_key key;
395 	struct ubifs_dent_node *dent;
396 	struct ubifs_info *c;
397 	struct file *file;
398 	struct dentry *dentry;
399 	struct inode *dir;
400 	int ret = 0;
401 
402 	file = kzalloc(sizeof(struct file), 0);
403 	dentry = kzalloc(sizeof(struct dentry), 0);
404 	dir = kzalloc(sizeof(struct inode), 0);
405 	if (!file || !dentry || !dir) {
406 		printf("%s: Error, no memory for malloc!\n", __func__);
407 		err = -ENOMEM;
408 		goto out;
409 	}
410 
411 	dir->i_sb = sb;
412 	file->f_path.dentry = dentry;
413 	file->f_path.dentry->d_parent = dentry;
414 	file->f_path.dentry->d_inode = dir;
415 	file->f_path.dentry->d_inode->i_ino = root_inum;
416 	c = sb->s_fs_info;
417 
418 	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
419 
420 	/* Find the first entry in TNC and save it */
421 	lowest_dent_key(c, &key, dir->i_ino);
422 	nm.name = NULL;
423 	dent = ubifs_tnc_next_ent(c, &key, &nm);
424 	if (IS_ERR(dent)) {
425 		err = PTR_ERR(dent);
426 		goto out;
427 	}
428 
429 	file->f_pos = key_hash_flash(c, &dent->key);
430 	file->private_data = dent;
431 
432 	while (1) {
433 		dbg_gen("feed '%s', ino %llu, new f_pos %#x",
434 			dent->name, (unsigned long long)le64_to_cpu(dent->inum),
435 			key_hash_flash(c, &dent->key));
436 		ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum);
437 
438 		nm.len = le16_to_cpu(dent->nlen);
439 		if ((strncmp(dirname, (char *)dent->name, nm.len) == 0) &&
440 		    (strlen(dirname) == nm.len)) {
441 			*inum = le64_to_cpu(dent->inum);
442 			ret = 1;
443 			goto out_free;
444 		}
445 
446 		/* Switch to the next entry */
447 		key_read(c, &dent->key, &key);
448 		nm.name = (char *)dent->name;
449 		dent = ubifs_tnc_next_ent(c, &key, &nm);
450 		if (IS_ERR(dent)) {
451 			err = PTR_ERR(dent);
452 			goto out;
453 		}
454 
455 		kfree(file->private_data);
456 		file->f_pos = key_hash_flash(c, &dent->key);
457 		file->private_data = dent;
458 		cond_resched();
459 	}
460 
461 out:
462 	if (err != -ENOENT)
463 		ubifs_err("cannot find next direntry, error %d", err);
464 
465 out_free:
466 	if (file->private_data)
467 		kfree(file->private_data);
468 	if (file)
469 		free(file);
470 	if (dentry)
471 		free(dentry);
472 	if (dir)
473 		free(dir);
474 
475 	return ret;
476 }
477 
478 static unsigned long ubifs_findfile(struct super_block *sb, char *filename)
479 {
480 	int ret;
481 	char *next;
482 	char fpath[128];
483 	char symlinkpath[128];
484 	char *name = fpath;
485 	unsigned long root_inum = 1;
486 	unsigned long inum;
487 	int symlink_count = 0; /* Don't allow symlink recursion */
488 	char link_name[64];
489 
490 	strcpy(fpath, filename);
491 
492 	/* Remove all leading slashes */
493 	while (*name == '/')
494 		name++;
495 
496 	/*
497 	 * Handle root-direcoty ('/')
498 	 */
499 	inum = root_inum;
500 	if (!name || *name == '\0')
501 		return inum;
502 
503 	for (;;) {
504 		struct inode *inode;
505 		struct ubifs_inode *ui;
506 
507 		/* Extract the actual part from the pathname.  */
508 		next = strchr(name, '/');
509 		if (next) {
510 			/* Remove all leading slashes.  */
511 			while (*next == '/')
512 				*(next++) = '\0';
513 		}
514 
515 		ret = ubifs_finddir(sb, name, root_inum, &inum);
516 		if (!ret)
517 			return 0;
518 		inode = ubifs_iget(sb, inum);
519 
520 		if (!inode)
521 			return 0;
522 		ui = ubifs_inode(inode);
523 
524 		if ((inode->i_mode & S_IFMT) == S_IFLNK) {
525 			char buf[128];
526 
527 			/* We have some sort of symlink recursion, bail out */
528 			if (symlink_count++ > 8) {
529 				printf("Symlink recursion, aborting\n");
530 				return 0;
531 			}
532 			memcpy(link_name, ui->data, ui->data_len);
533 			link_name[ui->data_len] = '\0';
534 
535 			if (link_name[0] == '/') {
536 				/* Absolute path, redo everything without
537 				 * the leading slash */
538 				next = name = link_name + 1;
539 				root_inum = 1;
540 				continue;
541 			}
542 			/* Relative to cur dir */
543 			sprintf(buf, "%s/%s",
544 					link_name, next == NULL ? "" : next);
545 			memcpy(symlinkpath, buf, sizeof(buf));
546 			next = name = symlinkpath;
547 			continue;
548 		}
549 
550 		/*
551 		 * Check if directory with this name exists
552 		 */
553 
554 		/* Found the node!  */
555 		if (!next || *next == '\0')
556 			return inum;
557 
558 		root_inum = inum;
559 		name = next;
560 	}
561 
562 	return 0;
563 }
564 
565 int ubifs_ls(char *filename)
566 {
567 	struct ubifs_info *c = ubifs_sb->s_fs_info;
568 	struct file *file;
569 	struct dentry *dentry;
570 	struct inode *dir;
571 	void *dirent = NULL;
572 	unsigned long inum;
573 	int ret = 0;
574 
575 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
576 	inum = ubifs_findfile(ubifs_sb, filename);
577 	if (!inum) {
578 		ret = -1;
579 		goto out;
580 	}
581 
582 	file = kzalloc(sizeof(struct file), 0);
583 	dentry = kzalloc(sizeof(struct dentry), 0);
584 	dir = kzalloc(sizeof(struct inode), 0);
585 	if (!file || !dentry || !dir) {
586 		printf("%s: Error, no memory for malloc!\n", __func__);
587 		ret = -ENOMEM;
588 		goto out_mem;
589 	}
590 
591 	dir->i_sb = ubifs_sb;
592 	file->f_path.dentry = dentry;
593 	file->f_path.dentry->d_parent = dentry;
594 	file->f_path.dentry->d_inode = dir;
595 	file->f_path.dentry->d_inode->i_ino = inum;
596 	file->f_pos = 1;
597 	file->private_data = NULL;
598 	ubifs_printdir(file, dirent);
599 
600 out_mem:
601 	if (file)
602 		free(file);
603 	if (dentry)
604 		free(dentry);
605 	if (dir)
606 		free(dir);
607 
608 out:
609 	ubi_close_volume(c->ubi);
610 	return ret;
611 }
612 
613 /*
614  * ubifsload...
615  */
616 
617 /* file.c */
618 
619 static inline void *kmap(struct page *page)
620 {
621 	return page->addr;
622 }
623 
624 static int read_block(struct inode *inode, void *addr, unsigned int block,
625 		      struct ubifs_data_node *dn)
626 {
627 	struct ubifs_info *c = inode->i_sb->s_fs_info;
628 	int err, len, out_len;
629 	union ubifs_key key;
630 	unsigned int dlen;
631 
632 	data_key_init(c, &key, inode->i_ino, block);
633 	err = ubifs_tnc_lookup(c, &key, dn);
634 	if (err) {
635 		if (err == -ENOENT)
636 			/* Not found, so it must be a hole */
637 			memset(addr, 0, UBIFS_BLOCK_SIZE);
638 		return err;
639 	}
640 
641 	ubifs_assert(le64_to_cpu(dn->ch.sqnum) > ubifs_inode(inode)->creat_sqnum);
642 
643 	len = le32_to_cpu(dn->size);
644 	if (len <= 0 || len > UBIFS_BLOCK_SIZE)
645 		goto dump;
646 
647 	dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
648 	out_len = UBIFS_BLOCK_SIZE;
649 	err = ubifs_decompress(&dn->data, dlen, addr, &out_len,
650 			       le16_to_cpu(dn->compr_type));
651 	if (err || len != out_len)
652 		goto dump;
653 
654 	/*
655 	 * Data length can be less than a full block, even for blocks that are
656 	 * not the last in the file (e.g., as a result of making a hole and
657 	 * appending data). Ensure that the remainder is zeroed out.
658 	 */
659 	if (len < UBIFS_BLOCK_SIZE)
660 		memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
661 
662 	return 0;
663 
664 dump:
665 	ubifs_err("bad data node (block %u, inode %lu)",
666 		  block, inode->i_ino);
667 	ubifs_dump_node(c, dn);
668 	return -EINVAL;
669 }
670 
671 static int do_readpage(struct ubifs_info *c, struct inode *inode,
672 		       struct page *page, int last_block_size)
673 {
674 	void *addr;
675 	int err = 0, i;
676 	unsigned int block, beyond;
677 	struct ubifs_data_node *dn;
678 	loff_t i_size = inode->i_size;
679 
680 	dbg_gen("ino %lu, pg %lu, i_size %lld",
681 		inode->i_ino, page->index, i_size);
682 
683 	addr = kmap(page);
684 
685 	block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
686 	beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
687 	if (block >= beyond) {
688 		/* Reading beyond inode */
689 		memset(addr, 0, PAGE_CACHE_SIZE);
690 		goto out;
691 	}
692 
693 	dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
694 	if (!dn)
695 		return -ENOMEM;
696 
697 	i = 0;
698 	while (1) {
699 		int ret;
700 
701 		if (block >= beyond) {
702 			/* Reading beyond inode */
703 			err = -ENOENT;
704 			memset(addr, 0, UBIFS_BLOCK_SIZE);
705 		} else {
706 			/*
707 			 * Reading last block? Make sure to not write beyond
708 			 * the requested size in the destination buffer.
709 			 */
710 			if (((block + 1) == beyond) || last_block_size) {
711 				void *buff;
712 				int dlen;
713 
714 				/*
715 				 * We need to buffer the data locally for the
716 				 * last block. This is to not pad the
717 				 * destination area to a multiple of
718 				 * UBIFS_BLOCK_SIZE.
719 				 */
720 				buff = malloc(UBIFS_BLOCK_SIZE);
721 				if (!buff) {
722 					printf("%s: Error, malloc fails!\n",
723 					       __func__);
724 					err = -ENOMEM;
725 					break;
726 				}
727 
728 				/* Read block-size into temp buffer */
729 				ret = read_block(inode, buff, block, dn);
730 				if (ret) {
731 					err = ret;
732 					if (err != -ENOENT) {
733 						free(buff);
734 						break;
735 					}
736 				}
737 
738 				if (last_block_size)
739 					dlen = last_block_size;
740 				else
741 					dlen = le32_to_cpu(dn->size);
742 
743 				/* Now copy required size back to dest */
744 				memcpy(addr, buff, dlen);
745 
746 				free(buff);
747 			} else {
748 				ret = read_block(inode, addr, block, dn);
749 				if (ret) {
750 					err = ret;
751 					if (err != -ENOENT)
752 						break;
753 				}
754 			}
755 		}
756 		if (++i >= UBIFS_BLOCKS_PER_PAGE)
757 			break;
758 		block += 1;
759 		addr += UBIFS_BLOCK_SIZE;
760 	}
761 	if (err) {
762 		if (err == -ENOENT) {
763 			/* Not found, so it must be a hole */
764 			dbg_gen("hole");
765 			goto out_free;
766 		}
767 		ubifs_err("cannot read page %lu of inode %lu, error %d",
768 			  page->index, inode->i_ino, err);
769 		goto error;
770 	}
771 
772 out_free:
773 	kfree(dn);
774 out:
775 	return 0;
776 
777 error:
778 	kfree(dn);
779 	return err;
780 }
781 
782 int ubifs_load(char *filename, u32 addr, u32 size)
783 {
784 	struct ubifs_info *c = ubifs_sb->s_fs_info;
785 	unsigned long inum;
786 	struct inode *inode;
787 	struct page page;
788 	int err = 0;
789 	int i;
790 	int count;
791 	int last_block_size = 0;
792 
793 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
794 	/* ubifs_findfile will resolve symlinks, so we know that we get
795 	 * the real file here */
796 	inum = ubifs_findfile(ubifs_sb, filename);
797 	if (!inum) {
798 		err = -1;
799 		goto out;
800 	}
801 
802 	/*
803 	 * Read file inode
804 	 */
805 	inode = ubifs_iget(ubifs_sb, inum);
806 	if (IS_ERR(inode)) {
807 		printf("%s: Error reading inode %ld!\n", __func__, inum);
808 		err = PTR_ERR(inode);
809 		goto out;
810 	}
811 
812 	/*
813 	 * If no size was specified or if size bigger than filesize
814 	 * set size to filesize
815 	 */
816 	if ((size == 0) || (size > inode->i_size))
817 		size = inode->i_size;
818 
819 	count = (size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
820 	printf("Loading file '%s' to addr 0x%08x with size %d (0x%08x)...\n",
821 	       filename, addr, size, size);
822 
823 	page.addr = (void *)addr;
824 	page.index = 0;
825 	page.inode = inode;
826 	for (i = 0; i < count; i++) {
827 		/*
828 		 * Make sure to not read beyond the requested size
829 		 */
830 		if (((i + 1) == count) && (size < inode->i_size))
831 			last_block_size = size - (i * PAGE_SIZE);
832 
833 		err = do_readpage(c, inode, &page, last_block_size);
834 		if (err)
835 			break;
836 
837 		page.addr += PAGE_SIZE;
838 		page.index++;
839 	}
840 
841 	if (err)
842 		printf("Error reading file '%s'\n", filename);
843 	else {
844 		setenv_hex("filesize", size);
845 		printf("Done\n");
846 	}
847 
848 	ubifs_iput(inode);
849 
850 out:
851 	ubi_close_volume(c->ubi);
852 	return err;
853 }
854