xref: /openbmc/u-boot/fs/ubifs/ubifs.c (revision 83d290c56fab2d38cd1ab4c4cc7099559c1d5046)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * This file is part of UBIFS.
4  *
5  * Copyright (C) 2006-2008 Nokia Corporation.
6  *
7  * (C) Copyright 2008-2010
8  * Stefan Roese, DENX Software Engineering, sr@denx.de.
9  *
10  * Authors: Artem Bityutskiy (Битюцкий Артём)
11  *          Adrian Hunter
12  */
13 
14 #include <common.h>
15 #include <memalign.h>
16 #include "ubifs.h"
17 #include <u-boot/zlib.h>
18 
19 #include <linux/err.h>
20 #include <linux/lzo.h>
21 
22 DECLARE_GLOBAL_DATA_PTR;
23 
24 /* compress.c */
25 
26 /*
27  * We need a wrapper for zunzip() because the parameters are
28  * incompatible with the lzo decompressor.
29  */
30 static int gzip_decompress(const unsigned char *in, size_t in_len,
31 			   unsigned char *out, size_t *out_len)
32 {
33 	return zunzip(out, *out_len, (unsigned char *)in,
34 		      (unsigned long *)out_len, 0, 0);
35 }
36 
37 /* Fake description object for the "none" compressor */
38 static struct ubifs_compressor none_compr = {
39 	.compr_type = UBIFS_COMPR_NONE,
40 	.name = "none",
41 	.capi_name = "",
42 	.decompress = NULL,
43 };
44 
45 static struct ubifs_compressor lzo_compr = {
46 	.compr_type = UBIFS_COMPR_LZO,
47 #ifndef __UBOOT__
48 	.comp_mutex = &lzo_mutex,
49 #endif
50 	.name = "lzo",
51 	.capi_name = "lzo",
52 	.decompress = lzo1x_decompress_safe,
53 };
54 
55 static struct ubifs_compressor zlib_compr = {
56 	.compr_type = UBIFS_COMPR_ZLIB,
57 #ifndef __UBOOT__
58 	.comp_mutex = &deflate_mutex,
59 	.decomp_mutex = &inflate_mutex,
60 #endif
61 	.name = "zlib",
62 	.capi_name = "deflate",
63 	.decompress = gzip_decompress,
64 };
65 
66 /* All UBIFS compressors */
67 struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT];
68 
69 
70 #ifdef __UBOOT__
71 /* from mm/util.c */
72 
73 /**
74  * kmemdup - duplicate region of memory
75  *
76  * @src: memory region to duplicate
77  * @len: memory region length
78  * @gfp: GFP mask to use
79  */
80 void *kmemdup(const void *src, size_t len, gfp_t gfp)
81 {
82 	void *p;
83 
84 	p = kmalloc(len, gfp);
85 	if (p)
86 		memcpy(p, src, len);
87 	return p;
88 }
89 
90 struct crypto_comp {
91 	int compressor;
92 };
93 
94 static inline struct crypto_comp
95 *crypto_alloc_comp(const char *alg_name, u32 type, u32 mask)
96 {
97 	struct ubifs_compressor *comp;
98 	struct crypto_comp *ptr;
99 	int i = 0;
100 
101 	ptr = malloc_cache_aligned(sizeof(struct crypto_comp));
102 	while (i < UBIFS_COMPR_TYPES_CNT) {
103 		comp = ubifs_compressors[i];
104 		if (!comp) {
105 			i++;
106 			continue;
107 		}
108 		if (strncmp(alg_name, comp->capi_name, strlen(alg_name)) == 0) {
109 			ptr->compressor = i;
110 			return ptr;
111 		}
112 		i++;
113 	}
114 	if (i >= UBIFS_COMPR_TYPES_CNT) {
115 		dbg_gen("invalid compression type %s", alg_name);
116 		free (ptr);
117 		return NULL;
118 	}
119 	return ptr;
120 }
121 static inline int
122 crypto_comp_decompress(const struct ubifs_info *c, struct crypto_comp *tfm,
123 		       const u8 *src, unsigned int slen, u8 *dst,
124 		       unsigned int *dlen)
125 {
126 	struct ubifs_compressor *compr = ubifs_compressors[tfm->compressor];
127 	int err;
128 
129 	if (compr->compr_type == UBIFS_COMPR_NONE) {
130 		memcpy(dst, src, slen);
131 		*dlen = slen;
132 		return 0;
133 	}
134 
135 	err = compr->decompress(src, slen, dst, (size_t *)dlen);
136 	if (err)
137 		ubifs_err(c, "cannot decompress %d bytes, compressor %s, "
138 			  "error %d", slen, compr->name, err);
139 
140 	return err;
141 
142 	return 0;
143 }
144 
145 /* from shrinker.c */
146 
147 /* Global clean znode counter (for all mounted UBIFS instances) */
148 atomic_long_t ubifs_clean_zn_cnt;
149 
150 #endif
151 
152 /**
153  * ubifs_decompress - decompress data.
154  * @in_buf: data to decompress
155  * @in_len: length of the data to decompress
156  * @out_buf: output buffer where decompressed data should
157  * @out_len: output length is returned here
158  * @compr_type: type of compression
159  *
160  * This function decompresses data from buffer @in_buf into buffer @out_buf.
161  * The length of the uncompressed data is returned in @out_len. This functions
162  * returns %0 on success or a negative error code on failure.
163  */
164 int ubifs_decompress(const struct ubifs_info *c, const void *in_buf,
165 		     int in_len, void *out_buf, int *out_len, int compr_type)
166 {
167 	int err;
168 	struct ubifs_compressor *compr;
169 
170 	if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) {
171 		ubifs_err(c, "invalid compression type %d", compr_type);
172 		return -EINVAL;
173 	}
174 
175 	compr = ubifs_compressors[compr_type];
176 
177 	if (unlikely(!compr->capi_name)) {
178 		ubifs_err(c, "%s compression is not compiled in", compr->name);
179 		return -EINVAL;
180 	}
181 
182 	if (compr_type == UBIFS_COMPR_NONE) {
183 		memcpy(out_buf, in_buf, in_len);
184 		*out_len = in_len;
185 		return 0;
186 	}
187 
188 	if (compr->decomp_mutex)
189 		mutex_lock(compr->decomp_mutex);
190 	err = crypto_comp_decompress(c, compr->cc, in_buf, in_len, out_buf,
191 				     (unsigned int *)out_len);
192 	if (compr->decomp_mutex)
193 		mutex_unlock(compr->decomp_mutex);
194 	if (err)
195 		ubifs_err(c, "cannot decompress %d bytes, compressor %s,"
196 			  " error %d", in_len, compr->name, err);
197 
198 	return err;
199 }
200 
201 /**
202  * compr_init - initialize a compressor.
203  * @compr: compressor description object
204  *
205  * This function initializes the requested compressor and returns zero in case
206  * of success or a negative error code in case of failure.
207  */
208 static int __init compr_init(struct ubifs_compressor *compr)
209 {
210 	ubifs_compressors[compr->compr_type] = compr;
211 
212 #ifdef CONFIG_NEEDS_MANUAL_RELOC
213 	ubifs_compressors[compr->compr_type]->name += gd->reloc_off;
214 	ubifs_compressors[compr->compr_type]->capi_name += gd->reloc_off;
215 	ubifs_compressors[compr->compr_type]->decompress += gd->reloc_off;
216 #endif
217 
218 	if (compr->capi_name) {
219 		compr->cc = crypto_alloc_comp(compr->capi_name, 0, 0);
220 		if (IS_ERR(compr->cc)) {
221 			dbg_gen("cannot initialize compressor %s,"
222 				  " error %ld", compr->name,
223 				  PTR_ERR(compr->cc));
224 			return PTR_ERR(compr->cc);
225 		}
226 	}
227 
228 	return 0;
229 }
230 
231 /**
232  * ubifs_compressors_init - initialize UBIFS compressors.
233  *
234  * This function initializes the compressor which were compiled in. Returns
235  * zero in case of success and a negative error code in case of failure.
236  */
237 int __init ubifs_compressors_init(void)
238 {
239 	int err;
240 
241 	err = compr_init(&lzo_compr);
242 	if (err)
243 		return err;
244 
245 	err = compr_init(&zlib_compr);
246 	if (err)
247 		return err;
248 
249 	err = compr_init(&none_compr);
250 	if (err)
251 		return err;
252 
253 	return 0;
254 }
255 
256 /*
257  * ubifsls...
258  */
259 
260 static int filldir(struct ubifs_info *c, const char *name, int namlen,
261 		   u64 ino, unsigned int d_type)
262 {
263 	struct inode *inode;
264 	char filetime[32];
265 
266 	switch (d_type) {
267 	case UBIFS_ITYPE_REG:
268 		printf("\t");
269 		break;
270 	case UBIFS_ITYPE_DIR:
271 		printf("<DIR>\t");
272 		break;
273 	case UBIFS_ITYPE_LNK:
274 		printf("<LNK>\t");
275 		break;
276 	default:
277 		printf("other\t");
278 		break;
279 	}
280 
281 	inode = ubifs_iget(c->vfs_sb, ino);
282 	if (IS_ERR(inode)) {
283 		printf("%s: Error in ubifs_iget(), ino=%lld ret=%p!\n",
284 		       __func__, ino, inode);
285 		return -1;
286 	}
287 	ctime_r((time_t *)&inode->i_mtime, filetime);
288 	printf("%9lld  %24.24s  ", inode->i_size, filetime);
289 #ifndef __UBOOT__
290 	ubifs_iput(inode);
291 #endif
292 
293 	printf("%s\n", name);
294 
295 	return 0;
296 }
297 
298 static int ubifs_printdir(struct file *file, void *dirent)
299 {
300 	int err, over = 0;
301 	struct qstr nm;
302 	union ubifs_key key;
303 	struct ubifs_dent_node *dent;
304 	struct inode *dir = file->f_path.dentry->d_inode;
305 	struct ubifs_info *c = dir->i_sb->s_fs_info;
306 
307 	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
308 
309 	if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
310 		/*
311 		 * The directory was seek'ed to a senseless position or there
312 		 * are no more entries.
313 		 */
314 		return 0;
315 
316 	if (file->f_pos == 1) {
317 		/* Find the first entry in TNC and save it */
318 		lowest_dent_key(c, &key, dir->i_ino);
319 		nm.name = NULL;
320 		dent = ubifs_tnc_next_ent(c, &key, &nm);
321 		if (IS_ERR(dent)) {
322 			err = PTR_ERR(dent);
323 			goto out;
324 		}
325 
326 		file->f_pos = key_hash_flash(c, &dent->key);
327 		file->private_data = dent;
328 	}
329 
330 	dent = file->private_data;
331 	if (!dent) {
332 		/*
333 		 * The directory was seek'ed to and is now readdir'ed.
334 		 * Find the entry corresponding to @file->f_pos or the
335 		 * closest one.
336 		 */
337 		dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
338 		nm.name = NULL;
339 		dent = ubifs_tnc_next_ent(c, &key, &nm);
340 		if (IS_ERR(dent)) {
341 			err = PTR_ERR(dent);
342 			goto out;
343 		}
344 		file->f_pos = key_hash_flash(c, &dent->key);
345 		file->private_data = dent;
346 	}
347 
348 	while (1) {
349 		dbg_gen("feed '%s', ino %llu, new f_pos %#x",
350 			dent->name, (unsigned long long)le64_to_cpu(dent->inum),
351 			key_hash_flash(c, &dent->key));
352 		ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum);
353 
354 		nm.len = le16_to_cpu(dent->nlen);
355 		over = filldir(c, (char *)dent->name, nm.len,
356 			       le64_to_cpu(dent->inum), dent->type);
357 		if (over)
358 			return 0;
359 
360 		/* Switch to the next entry */
361 		key_read(c, &dent->key, &key);
362 		nm.name = (char *)dent->name;
363 		dent = ubifs_tnc_next_ent(c, &key, &nm);
364 		if (IS_ERR(dent)) {
365 			err = PTR_ERR(dent);
366 			goto out;
367 		}
368 
369 		kfree(file->private_data);
370 		file->f_pos = key_hash_flash(c, &dent->key);
371 		file->private_data = dent;
372 		cond_resched();
373 	}
374 
375 out:
376 	if (err != -ENOENT) {
377 		ubifs_err(c, "cannot find next direntry, error %d", err);
378 		return err;
379 	}
380 
381 	kfree(file->private_data);
382 	file->private_data = NULL;
383 	file->f_pos = 2;
384 	return 0;
385 }
386 
387 static int ubifs_finddir(struct super_block *sb, char *dirname,
388 			 unsigned long root_inum, unsigned long *inum)
389 {
390 	int err;
391 	struct qstr nm;
392 	union ubifs_key key;
393 	struct ubifs_dent_node *dent;
394 	struct ubifs_info *c;
395 	struct file *file;
396 	struct dentry *dentry;
397 	struct inode *dir;
398 	int ret = 0;
399 
400 	file = kzalloc(sizeof(struct file), 0);
401 	dentry = kzalloc(sizeof(struct dentry), 0);
402 	dir = kzalloc(sizeof(struct inode), 0);
403 	if (!file || !dentry || !dir) {
404 		printf("%s: Error, no memory for malloc!\n", __func__);
405 		err = -ENOMEM;
406 		goto out;
407 	}
408 
409 	dir->i_sb = sb;
410 	file->f_path.dentry = dentry;
411 	file->f_path.dentry->d_parent = dentry;
412 	file->f_path.dentry->d_inode = dir;
413 	file->f_path.dentry->d_inode->i_ino = root_inum;
414 	c = sb->s_fs_info;
415 
416 	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
417 
418 	/* Find the first entry in TNC and save it */
419 	lowest_dent_key(c, &key, dir->i_ino);
420 	nm.name = NULL;
421 	dent = ubifs_tnc_next_ent(c, &key, &nm);
422 	if (IS_ERR(dent)) {
423 		err = PTR_ERR(dent);
424 		goto out;
425 	}
426 
427 	file->f_pos = key_hash_flash(c, &dent->key);
428 	file->private_data = dent;
429 
430 	while (1) {
431 		dbg_gen("feed '%s', ino %llu, new f_pos %#x",
432 			dent->name, (unsigned long long)le64_to_cpu(dent->inum),
433 			key_hash_flash(c, &dent->key));
434 		ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum);
435 
436 		nm.len = le16_to_cpu(dent->nlen);
437 		if ((strncmp(dirname, (char *)dent->name, nm.len) == 0) &&
438 		    (strlen(dirname) == nm.len)) {
439 			*inum = le64_to_cpu(dent->inum);
440 			ret = 1;
441 			goto out_free;
442 		}
443 
444 		/* Switch to the next entry */
445 		key_read(c, &dent->key, &key);
446 		nm.name = (char *)dent->name;
447 		dent = ubifs_tnc_next_ent(c, &key, &nm);
448 		if (IS_ERR(dent)) {
449 			err = PTR_ERR(dent);
450 			goto out;
451 		}
452 
453 		kfree(file->private_data);
454 		file->f_pos = key_hash_flash(c, &dent->key);
455 		file->private_data = dent;
456 		cond_resched();
457 	}
458 
459 out:
460 	if (err != -ENOENT)
461 		dbg_gen("cannot find next direntry, error %d", err);
462 
463 out_free:
464 	kfree(file->private_data);
465 	free(file);
466 	free(dentry);
467 	free(dir);
468 
469 	return ret;
470 }
471 
472 static unsigned long ubifs_findfile(struct super_block *sb, char *filename)
473 {
474 	int ret;
475 	char *next;
476 	char fpath[128];
477 	char symlinkpath[128];
478 	char *name = fpath;
479 	unsigned long root_inum = 1;
480 	unsigned long inum;
481 	int symlink_count = 0; /* Don't allow symlink recursion */
482 	char link_name[64];
483 
484 	strcpy(fpath, filename);
485 
486 	/* Remove all leading slashes */
487 	while (*name == '/')
488 		name++;
489 
490 	/*
491 	 * Handle root-direcoty ('/')
492 	 */
493 	inum = root_inum;
494 	if (!name || *name == '\0')
495 		return inum;
496 
497 	for (;;) {
498 		struct inode *inode;
499 		struct ubifs_inode *ui;
500 
501 		/* Extract the actual part from the pathname.  */
502 		next = strchr(name, '/');
503 		if (next) {
504 			/* Remove all leading slashes.  */
505 			while (*next == '/')
506 				*(next++) = '\0';
507 		}
508 
509 		ret = ubifs_finddir(sb, name, root_inum, &inum);
510 		if (!ret)
511 			return 0;
512 		inode = ubifs_iget(sb, inum);
513 
514 		if (!inode)
515 			return 0;
516 		ui = ubifs_inode(inode);
517 
518 		if ((inode->i_mode & S_IFMT) == S_IFLNK) {
519 			char buf[128];
520 
521 			/* We have some sort of symlink recursion, bail out */
522 			if (symlink_count++ > 8) {
523 				printf("Symlink recursion, aborting\n");
524 				return 0;
525 			}
526 			memcpy(link_name, ui->data, ui->data_len);
527 			link_name[ui->data_len] = '\0';
528 
529 			if (link_name[0] == '/') {
530 				/* Absolute path, redo everything without
531 				 * the leading slash */
532 				next = name = link_name + 1;
533 				root_inum = 1;
534 				continue;
535 			}
536 			/* Relative to cur dir */
537 			sprintf(buf, "%s/%s",
538 					link_name, next == NULL ? "" : next);
539 			memcpy(symlinkpath, buf, sizeof(buf));
540 			next = name = symlinkpath;
541 			continue;
542 		}
543 
544 		/*
545 		 * Check if directory with this name exists
546 		 */
547 
548 		/* Found the node!  */
549 		if (!next || *next == '\0')
550 			return inum;
551 
552 		root_inum = inum;
553 		name = next;
554 	}
555 
556 	return 0;
557 }
558 
559 int ubifs_set_blk_dev(struct blk_desc *rbdd, disk_partition_t *info)
560 {
561 	if (rbdd) {
562 		debug("UBIFS cannot be used with normal block devices\n");
563 		return -1;
564 	}
565 
566 	/*
567 	 * Should never happen since blk_get_device_part_str() already checks
568 	 * this, but better safe then sorry.
569 	 */
570 	if (!ubifs_is_mounted()) {
571 		debug("UBIFS not mounted, use ubifsmount to mount volume first!\n");
572 		return -1;
573 	}
574 
575 	return 0;
576 }
577 
578 int ubifs_ls(const char *filename)
579 {
580 	struct ubifs_info *c = ubifs_sb->s_fs_info;
581 	struct file *file;
582 	struct dentry *dentry;
583 	struct inode *dir;
584 	void *dirent = NULL;
585 	unsigned long inum;
586 	int ret = 0;
587 
588 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
589 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
590 	if (!inum) {
591 		ret = -1;
592 		goto out;
593 	}
594 
595 	file = kzalloc(sizeof(struct file), 0);
596 	dentry = kzalloc(sizeof(struct dentry), 0);
597 	dir = kzalloc(sizeof(struct inode), 0);
598 	if (!file || !dentry || !dir) {
599 		printf("%s: Error, no memory for malloc!\n", __func__);
600 		ret = -ENOMEM;
601 		goto out_mem;
602 	}
603 
604 	dir->i_sb = ubifs_sb;
605 	file->f_path.dentry = dentry;
606 	file->f_path.dentry->d_parent = dentry;
607 	file->f_path.dentry->d_inode = dir;
608 	file->f_path.dentry->d_inode->i_ino = inum;
609 	file->f_pos = 1;
610 	file->private_data = NULL;
611 	ubifs_printdir(file, dirent);
612 
613 out_mem:
614 	if (file)
615 		free(file);
616 	if (dentry)
617 		free(dentry);
618 	if (dir)
619 		free(dir);
620 
621 out:
622 	ubi_close_volume(c->ubi);
623 	return ret;
624 }
625 
626 int ubifs_exists(const char *filename)
627 {
628 	struct ubifs_info *c = ubifs_sb->s_fs_info;
629 	unsigned long inum;
630 
631 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
632 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
633 	ubi_close_volume(c->ubi);
634 
635 	return inum != 0;
636 }
637 
638 int ubifs_size(const char *filename, loff_t *size)
639 {
640 	struct ubifs_info *c = ubifs_sb->s_fs_info;
641 	unsigned long inum;
642 	struct inode *inode;
643 	int err = 0;
644 
645 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
646 
647 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
648 	if (!inum) {
649 		err = -1;
650 		goto out;
651 	}
652 
653 	inode = ubifs_iget(ubifs_sb, inum);
654 	if (IS_ERR(inode)) {
655 		printf("%s: Error reading inode %ld!\n", __func__, inum);
656 		err = PTR_ERR(inode);
657 		goto out;
658 	}
659 
660 	*size = inode->i_size;
661 
662 	ubifs_iput(inode);
663 out:
664 	ubi_close_volume(c->ubi);
665 	return err;
666 }
667 
668 /*
669  * ubifsload...
670  */
671 
672 /* file.c */
673 
674 static inline void *kmap(struct page *page)
675 {
676 	return page->addr;
677 }
678 
679 static int read_block(struct inode *inode, void *addr, unsigned int block,
680 		      struct ubifs_data_node *dn)
681 {
682 	struct ubifs_info *c = inode->i_sb->s_fs_info;
683 	int err, len, out_len;
684 	union ubifs_key key;
685 	unsigned int dlen;
686 
687 	data_key_init(c, &key, inode->i_ino, block);
688 	err = ubifs_tnc_lookup(c, &key, dn);
689 	if (err) {
690 		if (err == -ENOENT)
691 			/* Not found, so it must be a hole */
692 			memset(addr, 0, UBIFS_BLOCK_SIZE);
693 		return err;
694 	}
695 
696 	ubifs_assert(le64_to_cpu(dn->ch.sqnum) > ubifs_inode(inode)->creat_sqnum);
697 
698 	len = le32_to_cpu(dn->size);
699 	if (len <= 0 || len > UBIFS_BLOCK_SIZE)
700 		goto dump;
701 
702 	dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
703 	out_len = UBIFS_BLOCK_SIZE;
704 	err = ubifs_decompress(c, &dn->data, dlen, addr, &out_len,
705 			       le16_to_cpu(dn->compr_type));
706 	if (err || len != out_len)
707 		goto dump;
708 
709 	/*
710 	 * Data length can be less than a full block, even for blocks that are
711 	 * not the last in the file (e.g., as a result of making a hole and
712 	 * appending data). Ensure that the remainder is zeroed out.
713 	 */
714 	if (len < UBIFS_BLOCK_SIZE)
715 		memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
716 
717 	return 0;
718 
719 dump:
720 	ubifs_err(c, "bad data node (block %u, inode %lu)",
721 		  block, inode->i_ino);
722 	ubifs_dump_node(c, dn);
723 	return -EINVAL;
724 }
725 
726 static int do_readpage(struct ubifs_info *c, struct inode *inode,
727 		       struct page *page, int last_block_size)
728 {
729 	void *addr;
730 	int err = 0, i;
731 	unsigned int block, beyond;
732 	struct ubifs_data_node *dn;
733 	loff_t i_size = inode->i_size;
734 
735 	dbg_gen("ino %lu, pg %lu, i_size %lld",
736 		inode->i_ino, page->index, i_size);
737 
738 	addr = kmap(page);
739 
740 	block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
741 	beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
742 	if (block >= beyond) {
743 		/* Reading beyond inode */
744 		memset(addr, 0, PAGE_CACHE_SIZE);
745 		goto out;
746 	}
747 
748 	dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
749 	if (!dn)
750 		return -ENOMEM;
751 
752 	i = 0;
753 	while (1) {
754 		int ret;
755 
756 		if (block >= beyond) {
757 			/* Reading beyond inode */
758 			err = -ENOENT;
759 			memset(addr, 0, UBIFS_BLOCK_SIZE);
760 		} else {
761 			/*
762 			 * Reading last block? Make sure to not write beyond
763 			 * the requested size in the destination buffer.
764 			 */
765 			if (((block + 1) == beyond) || last_block_size) {
766 				void *buff;
767 				int dlen;
768 
769 				/*
770 				 * We need to buffer the data locally for the
771 				 * last block. This is to not pad the
772 				 * destination area to a multiple of
773 				 * UBIFS_BLOCK_SIZE.
774 				 */
775 				buff = malloc_cache_aligned(UBIFS_BLOCK_SIZE);
776 				if (!buff) {
777 					printf("%s: Error, malloc fails!\n",
778 					       __func__);
779 					err = -ENOMEM;
780 					break;
781 				}
782 
783 				/* Read block-size into temp buffer */
784 				ret = read_block(inode, buff, block, dn);
785 				if (ret) {
786 					err = ret;
787 					if (err != -ENOENT) {
788 						free(buff);
789 						break;
790 					}
791 				}
792 
793 				if (last_block_size)
794 					dlen = last_block_size;
795 				else
796 					dlen = le32_to_cpu(dn->size);
797 
798 				/* Now copy required size back to dest */
799 				memcpy(addr, buff, dlen);
800 
801 				free(buff);
802 			} else {
803 				ret = read_block(inode, addr, block, dn);
804 				if (ret) {
805 					err = ret;
806 					if (err != -ENOENT)
807 						break;
808 				}
809 			}
810 		}
811 		if (++i >= UBIFS_BLOCKS_PER_PAGE)
812 			break;
813 		block += 1;
814 		addr += UBIFS_BLOCK_SIZE;
815 	}
816 	if (err) {
817 		if (err == -ENOENT) {
818 			/* Not found, so it must be a hole */
819 			dbg_gen("hole");
820 			goto out_free;
821 		}
822 		ubifs_err(c, "cannot read page %lu of inode %lu, error %d",
823 			  page->index, inode->i_ino, err);
824 		goto error;
825 	}
826 
827 out_free:
828 	kfree(dn);
829 out:
830 	return 0;
831 
832 error:
833 	kfree(dn);
834 	return err;
835 }
836 
837 int ubifs_read(const char *filename, void *buf, loff_t offset,
838 	       loff_t size, loff_t *actread)
839 {
840 	struct ubifs_info *c = ubifs_sb->s_fs_info;
841 	unsigned long inum;
842 	struct inode *inode;
843 	struct page page;
844 	int err = 0;
845 	int i;
846 	int count;
847 	int last_block_size = 0;
848 
849 	*actread = 0;
850 
851 	if (offset & (PAGE_SIZE - 1)) {
852 		printf("ubifs: Error offset must be a multiple of %d\n",
853 		       PAGE_SIZE);
854 		return -1;
855 	}
856 
857 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
858 	/* ubifs_findfile will resolve symlinks, so we know that we get
859 	 * the real file here */
860 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
861 	if (!inum) {
862 		err = -1;
863 		goto out;
864 	}
865 
866 	/*
867 	 * Read file inode
868 	 */
869 	inode = ubifs_iget(ubifs_sb, inum);
870 	if (IS_ERR(inode)) {
871 		printf("%s: Error reading inode %ld!\n", __func__, inum);
872 		err = PTR_ERR(inode);
873 		goto out;
874 	}
875 
876 	if (offset > inode->i_size) {
877 		printf("ubifs: Error offset (%lld) > file-size (%lld)\n",
878 		       offset, size);
879 		err = -1;
880 		goto put_inode;
881 	}
882 
883 	/*
884 	 * If no size was specified or if size bigger than filesize
885 	 * set size to filesize
886 	 */
887 	if ((size == 0) || (size > (inode->i_size - offset)))
888 		size = inode->i_size - offset;
889 
890 	count = (size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
891 
892 	page.addr = buf;
893 	page.index = offset / PAGE_SIZE;
894 	page.inode = inode;
895 	for (i = 0; i < count; i++) {
896 		/*
897 		 * Make sure to not read beyond the requested size
898 		 */
899 		if (((i + 1) == count) && (size < inode->i_size))
900 			last_block_size = size - (i * PAGE_SIZE);
901 
902 		err = do_readpage(c, inode, &page, last_block_size);
903 		if (err)
904 			break;
905 
906 		page.addr += PAGE_SIZE;
907 		page.index++;
908 	}
909 
910 	if (err) {
911 		printf("Error reading file '%s'\n", filename);
912 		*actread = i * PAGE_SIZE;
913 	} else {
914 		*actread = size;
915 	}
916 
917 put_inode:
918 	ubifs_iput(inode);
919 
920 out:
921 	ubi_close_volume(c->ubi);
922 	return err;
923 }
924 
925 void ubifs_close(void)
926 {
927 }
928 
929 /* Compat wrappers for common/cmd_ubifs.c */
930 int ubifs_load(char *filename, u32 addr, u32 size)
931 {
932 	loff_t actread;
933 	int err;
934 
935 	printf("Loading file '%s' to addr 0x%08x...\n", filename, addr);
936 
937 	err = ubifs_read(filename, (void *)(uintptr_t)addr, 0, size, &actread);
938 	if (err == 0) {
939 		env_set_hex("filesize", actread);
940 		printf("Done\n");
941 	}
942 
943 	return err;
944 }
945 
946 void uboot_ubifs_umount(void)
947 {
948 	if (ubifs_sb) {
949 		printf("Unmounting UBIFS volume %s!\n",
950 		       ((struct ubifs_info *)(ubifs_sb->s_fs_info))->vi.name);
951 		ubifs_umount(ubifs_sb->s_fs_info);
952 		ubifs_sb = NULL;
953 	}
954 }
955