xref: /openbmc/u-boot/fs/ubifs/ubifs.c (revision 6f443330)
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  */
gzip_decompress(const unsigned char * in,size_t in_len,unsigned char * out,size_t * out_len)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  */
kmemdup(const void * src,size_t len,gfp_t gfp)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
crypto_alloc_comp(const char * alg_name,u32 type,u32 mask)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
crypto_comp_decompress(const struct ubifs_info * c,struct crypto_comp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)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 	size_t tmp_len = *dlen;
129 
130 	if (compr->compr_type == UBIFS_COMPR_NONE) {
131 		memcpy(dst, src, slen);
132 		*dlen = slen;
133 		return 0;
134 	}
135 
136 	err = compr->decompress(src, slen, dst, &tmp_len);
137 	if (err)
138 		ubifs_err(c, "cannot decompress %d bytes, compressor %s, "
139 			  "error %d", slen, compr->name, err);
140 
141 	*dlen = tmp_len;
142 	return err;
143 
144 	return 0;
145 }
146 
147 /* from shrinker.c */
148 
149 /* Global clean znode counter (for all mounted UBIFS instances) */
150 atomic_long_t ubifs_clean_zn_cnt;
151 
152 #endif
153 
154 /**
155  * ubifs_decompress - decompress data.
156  * @in_buf: data to decompress
157  * @in_len: length of the data to decompress
158  * @out_buf: output buffer where decompressed data should
159  * @out_len: output length is returned here
160  * @compr_type: type of compression
161  *
162  * This function decompresses data from buffer @in_buf into buffer @out_buf.
163  * The length of the uncompressed data is returned in @out_len. This functions
164  * returns %0 on success or a negative error code on failure.
165  */
ubifs_decompress(const struct ubifs_info * c,const void * in_buf,int in_len,void * out_buf,int * out_len,int compr_type)166 int ubifs_decompress(const struct ubifs_info *c, const void *in_buf,
167 		     int in_len, void *out_buf, int *out_len, int compr_type)
168 {
169 	int err;
170 	struct ubifs_compressor *compr;
171 
172 	if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) {
173 		ubifs_err(c, "invalid compression type %d", compr_type);
174 		return -EINVAL;
175 	}
176 
177 	compr = ubifs_compressors[compr_type];
178 
179 	if (unlikely(!compr->capi_name)) {
180 		ubifs_err(c, "%s compression is not compiled in", compr->name);
181 		return -EINVAL;
182 	}
183 
184 	if (compr_type == UBIFS_COMPR_NONE) {
185 		memcpy(out_buf, in_buf, in_len);
186 		*out_len = in_len;
187 		return 0;
188 	}
189 
190 	if (compr->decomp_mutex)
191 		mutex_lock(compr->decomp_mutex);
192 	err = crypto_comp_decompress(c, compr->cc, in_buf, in_len, out_buf,
193 				     (unsigned int *)out_len);
194 	if (compr->decomp_mutex)
195 		mutex_unlock(compr->decomp_mutex);
196 	if (err)
197 		ubifs_err(c, "cannot decompress %d bytes, compressor %s,"
198 			  " error %d", in_len, compr->name, err);
199 
200 	return err;
201 }
202 
203 /**
204  * compr_init - initialize a compressor.
205  * @compr: compressor description object
206  *
207  * This function initializes the requested compressor and returns zero in case
208  * of success or a negative error code in case of failure.
209  */
compr_init(struct ubifs_compressor * compr)210 static int __init compr_init(struct ubifs_compressor *compr)
211 {
212 	ubifs_compressors[compr->compr_type] = compr;
213 
214 #ifdef CONFIG_NEEDS_MANUAL_RELOC
215 	ubifs_compressors[compr->compr_type]->name += gd->reloc_off;
216 	ubifs_compressors[compr->compr_type]->capi_name += gd->reloc_off;
217 	ubifs_compressors[compr->compr_type]->decompress += gd->reloc_off;
218 #endif
219 
220 	if (compr->capi_name) {
221 		compr->cc = crypto_alloc_comp(compr->capi_name, 0, 0);
222 		if (IS_ERR(compr->cc)) {
223 			dbg_gen("cannot initialize compressor %s,"
224 				  " error %ld", compr->name,
225 				  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  */
ubifs_compressors_init(void)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 
filldir(struct ubifs_info * c,const char * name,int namlen,u64 ino,unsigned int d_type)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 
ubifs_printdir(struct file * file,void * dirent)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 #ifndef __UBOOT__
355 		ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum);
356 #endif
357 
358 		nm.len = le16_to_cpu(dent->nlen);
359 		over = filldir(c, (char *)dent->name, nm.len,
360 			       le64_to_cpu(dent->inum), dent->type);
361 		if (over)
362 			return 0;
363 
364 		/* Switch to the next entry */
365 		key_read(c, &dent->key, &key);
366 		nm.name = (char *)dent->name;
367 		dent = ubifs_tnc_next_ent(c, &key, &nm);
368 		if (IS_ERR(dent)) {
369 			err = PTR_ERR(dent);
370 			goto out;
371 		}
372 
373 		kfree(file->private_data);
374 		file->f_pos = key_hash_flash(c, &dent->key);
375 		file->private_data = dent;
376 		cond_resched();
377 	}
378 
379 out:
380 	if (err != -ENOENT) {
381 		ubifs_err(c, "cannot find next direntry, error %d", err);
382 		return err;
383 	}
384 
385 	kfree(file->private_data);
386 	file->private_data = NULL;
387 	file->f_pos = 2;
388 	return 0;
389 }
390 
ubifs_finddir(struct super_block * sb,char * dirname,unsigned long root_inum,unsigned long * inum)391 static int ubifs_finddir(struct super_block *sb, char *dirname,
392 			 unsigned long root_inum, unsigned long *inum)
393 {
394 	int err;
395 	struct qstr nm;
396 	union ubifs_key key;
397 	struct ubifs_dent_node *dent;
398 	struct ubifs_info *c;
399 	struct file *file;
400 	struct dentry *dentry;
401 	struct inode *dir;
402 	int ret = 0;
403 
404 	file = kzalloc(sizeof(struct file), 0);
405 	dentry = kzalloc(sizeof(struct dentry), 0);
406 	dir = kzalloc(sizeof(struct inode), 0);
407 	if (!file || !dentry || !dir) {
408 		printf("%s: Error, no memory for malloc!\n", __func__);
409 		err = -ENOMEM;
410 		goto out;
411 	}
412 
413 	dir->i_sb = sb;
414 	file->f_path.dentry = dentry;
415 	file->f_path.dentry->d_parent = dentry;
416 	file->f_path.dentry->d_inode = dir;
417 	file->f_path.dentry->d_inode->i_ino = root_inum;
418 	c = sb->s_fs_info;
419 
420 	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
421 
422 	/* Find the first entry in TNC and save it */
423 	lowest_dent_key(c, &key, dir->i_ino);
424 	nm.name = NULL;
425 	dent = ubifs_tnc_next_ent(c, &key, &nm);
426 	if (IS_ERR(dent)) {
427 		err = PTR_ERR(dent);
428 		goto out;
429 	}
430 
431 	file->f_pos = key_hash_flash(c, &dent->key);
432 	file->private_data = dent;
433 
434 	while (1) {
435 		dbg_gen("feed '%s', ino %llu, new f_pos %#x",
436 			dent->name, (unsigned long long)le64_to_cpu(dent->inum),
437 			key_hash_flash(c, &dent->key));
438 #ifndef __UBOOT__
439 		ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum);
440 #endif
441 
442 		nm.len = le16_to_cpu(dent->nlen);
443 		if ((strncmp(dirname, (char *)dent->name, nm.len) == 0) &&
444 		    (strlen(dirname) == nm.len)) {
445 			*inum = le64_to_cpu(dent->inum);
446 			ret = 1;
447 			goto out_free;
448 		}
449 
450 		/* Switch to the next entry */
451 		key_read(c, &dent->key, &key);
452 		nm.name = (char *)dent->name;
453 		dent = ubifs_tnc_next_ent(c, &key, &nm);
454 		if (IS_ERR(dent)) {
455 			err = PTR_ERR(dent);
456 			goto out;
457 		}
458 
459 		kfree(file->private_data);
460 		file->f_pos = key_hash_flash(c, &dent->key);
461 		file->private_data = dent;
462 		cond_resched();
463 	}
464 
465 out:
466 	if (err != -ENOENT)
467 		dbg_gen("cannot find next direntry, error %d", err);
468 
469 out_free:
470 	kfree(file->private_data);
471 	free(file);
472 	free(dentry);
473 	free(dir);
474 
475 	return ret;
476 }
477 
ubifs_findfile(struct super_block * sb,char * filename)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 
ubifs_set_blk_dev(struct blk_desc * rbdd,disk_partition_t * info)565 int ubifs_set_blk_dev(struct blk_desc *rbdd, disk_partition_t *info)
566 {
567 	if (rbdd) {
568 		debug("UBIFS cannot be used with normal block devices\n");
569 		return -1;
570 	}
571 
572 	/*
573 	 * Should never happen since blk_get_device_part_str() already checks
574 	 * this, but better safe then sorry.
575 	 */
576 	if (!ubifs_is_mounted()) {
577 		debug("UBIFS not mounted, use ubifsmount to mount volume first!\n");
578 		return -1;
579 	}
580 
581 	return 0;
582 }
583 
ubifs_ls(const char * filename)584 int ubifs_ls(const char *filename)
585 {
586 	struct ubifs_info *c = ubifs_sb->s_fs_info;
587 	struct file *file;
588 	struct dentry *dentry;
589 	struct inode *dir;
590 	void *dirent = NULL;
591 	unsigned long inum;
592 	int ret = 0;
593 
594 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
595 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
596 	if (!inum) {
597 		ret = -1;
598 		goto out;
599 	}
600 
601 	file = kzalloc(sizeof(struct file), 0);
602 	dentry = kzalloc(sizeof(struct dentry), 0);
603 	dir = kzalloc(sizeof(struct inode), 0);
604 	if (!file || !dentry || !dir) {
605 		printf("%s: Error, no memory for malloc!\n", __func__);
606 		ret = -ENOMEM;
607 		goto out_mem;
608 	}
609 
610 	dir->i_sb = ubifs_sb;
611 	file->f_path.dentry = dentry;
612 	file->f_path.dentry->d_parent = dentry;
613 	file->f_path.dentry->d_inode = dir;
614 	file->f_path.dentry->d_inode->i_ino = inum;
615 	file->f_pos = 1;
616 	file->private_data = NULL;
617 	ubifs_printdir(file, dirent);
618 
619 out_mem:
620 	if (file)
621 		free(file);
622 	if (dentry)
623 		free(dentry);
624 	if (dir)
625 		free(dir);
626 
627 out:
628 	ubi_close_volume(c->ubi);
629 	return ret;
630 }
631 
ubifs_exists(const char * filename)632 int ubifs_exists(const char *filename)
633 {
634 	struct ubifs_info *c = ubifs_sb->s_fs_info;
635 	unsigned long inum;
636 
637 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
638 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
639 	ubi_close_volume(c->ubi);
640 
641 	return inum != 0;
642 }
643 
ubifs_size(const char * filename,loff_t * size)644 int ubifs_size(const char *filename, loff_t *size)
645 {
646 	struct ubifs_info *c = ubifs_sb->s_fs_info;
647 	unsigned long inum;
648 	struct inode *inode;
649 	int err = 0;
650 
651 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
652 
653 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
654 	if (!inum) {
655 		err = -1;
656 		goto out;
657 	}
658 
659 	inode = ubifs_iget(ubifs_sb, inum);
660 	if (IS_ERR(inode)) {
661 		printf("%s: Error reading inode %ld!\n", __func__, inum);
662 		err = PTR_ERR(inode);
663 		goto out;
664 	}
665 
666 	*size = inode->i_size;
667 
668 	ubifs_iput(inode);
669 out:
670 	ubi_close_volume(c->ubi);
671 	return err;
672 }
673 
674 /*
675  * ubifsload...
676  */
677 
678 /* file.c */
679 
kmap(struct page * page)680 static inline void *kmap(struct page *page)
681 {
682 	return page->addr;
683 }
684 
read_block(struct inode * inode,void * addr,unsigned int block,struct ubifs_data_node * dn)685 static int read_block(struct inode *inode, void *addr, unsigned int block,
686 		      struct ubifs_data_node *dn)
687 {
688 	struct ubifs_info *c = inode->i_sb->s_fs_info;
689 	int err, len, out_len;
690 	union ubifs_key key;
691 	unsigned int dlen;
692 
693 	data_key_init(c, &key, inode->i_ino, block);
694 	err = ubifs_tnc_lookup(c, &key, dn);
695 	if (err) {
696 		if (err == -ENOENT)
697 			/* Not found, so it must be a hole */
698 			memset(addr, 0, UBIFS_BLOCK_SIZE);
699 		return err;
700 	}
701 
702 	ubifs_assert(le64_to_cpu(dn->ch.sqnum) > ubifs_inode(inode)->creat_sqnum);
703 
704 	len = le32_to_cpu(dn->size);
705 	if (len <= 0 || len > UBIFS_BLOCK_SIZE)
706 		goto dump;
707 
708 	dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
709 	out_len = UBIFS_BLOCK_SIZE;
710 	err = ubifs_decompress(c, &dn->data, dlen, addr, &out_len,
711 			       le16_to_cpu(dn->compr_type));
712 	if (err || len != out_len)
713 		goto dump;
714 
715 	/*
716 	 * Data length can be less than a full block, even for blocks that are
717 	 * not the last in the file (e.g., as a result of making a hole and
718 	 * appending data). Ensure that the remainder is zeroed out.
719 	 */
720 	if (len < UBIFS_BLOCK_SIZE)
721 		memset(addr + len, 0, UBIFS_BLOCK_SIZE - len);
722 
723 	return 0;
724 
725 dump:
726 	ubifs_err(c, "bad data node (block %u, inode %lu)",
727 		  block, inode->i_ino);
728 	ubifs_dump_node(c, dn);
729 	return -EINVAL;
730 }
731 
do_readpage(struct ubifs_info * c,struct inode * inode,struct page * page,int last_block_size)732 static int do_readpage(struct ubifs_info *c, struct inode *inode,
733 		       struct page *page, int last_block_size)
734 {
735 	void *addr;
736 	int err = 0, i;
737 	unsigned int block, beyond;
738 	struct ubifs_data_node *dn;
739 	loff_t i_size = inode->i_size;
740 
741 	dbg_gen("ino %lu, pg %lu, i_size %lld",
742 		inode->i_ino, page->index, i_size);
743 
744 	addr = kmap(page);
745 
746 	block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT;
747 	beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
748 	if (block >= beyond) {
749 		/* Reading beyond inode */
750 		memset(addr, 0, PAGE_CACHE_SIZE);
751 		goto out;
752 	}
753 
754 	dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS);
755 	if (!dn)
756 		return -ENOMEM;
757 
758 	i = 0;
759 	while (1) {
760 		int ret;
761 
762 		if (block >= beyond) {
763 			/* Reading beyond inode */
764 			err = -ENOENT;
765 			memset(addr, 0, UBIFS_BLOCK_SIZE);
766 		} else {
767 			/*
768 			 * Reading last block? Make sure to not write beyond
769 			 * the requested size in the destination buffer.
770 			 */
771 			if (((block + 1) == beyond) || last_block_size) {
772 				void *buff;
773 				int dlen;
774 
775 				/*
776 				 * We need to buffer the data locally for the
777 				 * last block. This is to not pad the
778 				 * destination area to a multiple of
779 				 * UBIFS_BLOCK_SIZE.
780 				 */
781 				buff = malloc_cache_aligned(UBIFS_BLOCK_SIZE);
782 				if (!buff) {
783 					printf("%s: Error, malloc fails!\n",
784 					       __func__);
785 					err = -ENOMEM;
786 					break;
787 				}
788 
789 				/* Read block-size into temp buffer */
790 				ret = read_block(inode, buff, block, dn);
791 				if (ret) {
792 					err = ret;
793 					if (err != -ENOENT) {
794 						free(buff);
795 						break;
796 					}
797 				}
798 
799 				if (last_block_size)
800 					dlen = last_block_size;
801 				else
802 					dlen = le32_to_cpu(dn->size);
803 
804 				/* Now copy required size back to dest */
805 				memcpy(addr, buff, dlen);
806 
807 				free(buff);
808 			} else {
809 				ret = read_block(inode, addr, block, dn);
810 				if (ret) {
811 					err = ret;
812 					if (err != -ENOENT)
813 						break;
814 				}
815 			}
816 		}
817 		if (++i >= UBIFS_BLOCKS_PER_PAGE)
818 			break;
819 		block += 1;
820 		addr += UBIFS_BLOCK_SIZE;
821 	}
822 	if (err) {
823 		if (err == -ENOENT) {
824 			/* Not found, so it must be a hole */
825 			dbg_gen("hole");
826 			goto out_free;
827 		}
828 		ubifs_err(c, "cannot read page %lu of inode %lu, error %d",
829 			  page->index, inode->i_ino, err);
830 		goto error;
831 	}
832 
833 out_free:
834 	kfree(dn);
835 out:
836 	return 0;
837 
838 error:
839 	kfree(dn);
840 	return err;
841 }
842 
ubifs_read(const char * filename,void * buf,loff_t offset,loff_t size,loff_t * actread)843 int ubifs_read(const char *filename, void *buf, loff_t offset,
844 	       loff_t size, loff_t *actread)
845 {
846 	struct ubifs_info *c = ubifs_sb->s_fs_info;
847 	unsigned long inum;
848 	struct inode *inode;
849 	struct page page;
850 	int err = 0;
851 	int i;
852 	int count;
853 	int last_block_size = 0;
854 
855 	*actread = 0;
856 
857 	if (offset & (PAGE_SIZE - 1)) {
858 		printf("ubifs: Error offset must be a multiple of %d\n",
859 		       PAGE_SIZE);
860 		return -1;
861 	}
862 
863 	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
864 	/* ubifs_findfile will resolve symlinks, so we know that we get
865 	 * the real file here */
866 	inum = ubifs_findfile(ubifs_sb, (char *)filename);
867 	if (!inum) {
868 		err = -1;
869 		goto out;
870 	}
871 
872 	/*
873 	 * Read file inode
874 	 */
875 	inode = ubifs_iget(ubifs_sb, inum);
876 	if (IS_ERR(inode)) {
877 		printf("%s: Error reading inode %ld!\n", __func__, inum);
878 		err = PTR_ERR(inode);
879 		goto out;
880 	}
881 
882 	if (offset > inode->i_size) {
883 		printf("ubifs: Error offset (%lld) > file-size (%lld)\n",
884 		       offset, size);
885 		err = -1;
886 		goto put_inode;
887 	}
888 
889 	/*
890 	 * If no size was specified or if size bigger than filesize
891 	 * set size to filesize
892 	 */
893 	if ((size == 0) || (size > (inode->i_size - offset)))
894 		size = inode->i_size - offset;
895 
896 	count = (size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT;
897 
898 	page.addr = buf;
899 	page.index = offset / PAGE_SIZE;
900 	page.inode = inode;
901 	for (i = 0; i < count; i++) {
902 		/*
903 		 * Make sure to not read beyond the requested size
904 		 */
905 		if (((i + 1) == count) && (size < inode->i_size))
906 			last_block_size = size - (i * PAGE_SIZE);
907 
908 		err = do_readpage(c, inode, &page, last_block_size);
909 		if (err)
910 			break;
911 
912 		page.addr += PAGE_SIZE;
913 		page.index++;
914 	}
915 
916 	if (err) {
917 		printf("Error reading file '%s'\n", filename);
918 		*actread = i * PAGE_SIZE;
919 	} else {
920 		*actread = size;
921 	}
922 
923 put_inode:
924 	ubifs_iput(inode);
925 
926 out:
927 	ubi_close_volume(c->ubi);
928 	return err;
929 }
930 
ubifs_close(void)931 void ubifs_close(void)
932 {
933 }
934 
935 /* Compat wrappers for common/cmd_ubifs.c */
ubifs_load(char * filename,u32 addr,u32 size)936 int ubifs_load(char *filename, u32 addr, u32 size)
937 {
938 	loff_t actread;
939 	int err;
940 
941 	printf("Loading file '%s' to addr 0x%08x...\n", filename, addr);
942 
943 	err = ubifs_read(filename, (void *)(uintptr_t)addr, 0, size, &actread);
944 	if (err == 0) {
945 		env_set_hex("filesize", actread);
946 		printf("Done\n");
947 	}
948 
949 	return err;
950 }
951 
uboot_ubifs_umount(void)952 void uboot_ubifs_umount(void)
953 {
954 	if (ubifs_sb) {
955 		printf("Unmounting UBIFS volume %s!\n",
956 		       ((struct ubifs_info *)(ubifs_sb->s_fs_info))->vi.name);
957 		ubifs_umount(ubifs_sb->s_fs_info);
958 		ubifs_sb = NULL;
959 	}
960 }
961