fs/ubifs/ubifs.c

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