fs/isofs/inode.c

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This source file includes following definitions.
isofs_put_super
isofs_alloc_inode
isofs_free_inode
init_once
init_inodecache
destroy_inodecache
isofs_remount
isofs_hashi_common
isofs_dentry_cmp_common
isofs_hashi
isofs_dentry_cmpi
isofs_hash_common
isofs_hash_ms
isofs_hashi_ms
isofs_dentry_cmp_ms
isofs_dentry_cmpi_ms
parse_options
isofs_show_options
isofs_get_last_session
rootdir_empty
isofs_fill_super
isofs_statfs
isofs_get_blocks
isofs_get_block
isofs_bmap
isofs_bread
isofs_readpage
isofs_readpages
_isofs_bmap
isofs_read_level3_size
isofs_read_inode
isofs_iget5_test
isofs_iget5_set
__isofs_iget
isofs_mount
init_iso9660_fs
exit_iso9660_fs
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/fs/isofs/inode.c
   4  *
   5  *  (C) 1991  Linus Torvalds - minix filesystem
   6  *      1992, 1993, 1994  Eric Youngdale Modified for ISO 9660 filesystem.
   7  *      1994  Eberhard Mönkeberg - multi session handling.
   8  *      1995  Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
   9  *      1997  Gordon Chaffee - Joliet CDs
  10  *      1998  Eric Lammerts - ISO 9660 Level 3
  11  *      2004  Paul Serice - Inode Support pushed out from 4GB to 128GB
  12  *      2004  Paul Serice - NFS Export Operations
  13  */
  14 
  15 #include <linux/init.h>
  16 #include <linux/module.h>
  17 
  18 #include <linux/slab.h>
  19 #include <linux/cred.h>
  20 #include <linux/nls.h>
  21 #include <linux/ctype.h>
  22 #include <linux/statfs.h>
  23 #include <linux/cdrom.h>
  24 #include <linux/parser.h>
  25 #include <linux/mpage.h>
  26 #include <linux/user_namespace.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/blkdev.h>
  29 
  30 #include "isofs.h"
  31 #include "zisofs.h"
  32 
  33 /* max tz offset is 13 hours */
  34 #define MAX_TZ_OFFSET (52*15*60)
  35 
  36 #define BEQUIET
  37 
  38 static int isofs_hashi(const struct dentry *parent, struct qstr *qstr);
  39 static int isofs_dentry_cmpi(const struct dentry *dentry,
  40                 unsigned int len, const char *str, const struct qstr *name);
  41 
  42 #ifdef CONFIG_JOLIET
  43 static int isofs_hashi_ms(const struct dentry *parent, struct qstr *qstr);
  44 static int isofs_hash_ms(const struct dentry *parent, struct qstr *qstr);
  45 static int isofs_dentry_cmpi_ms(const struct dentry *dentry,
  46                 unsigned int len, const char *str, const struct qstr *name);
  47 static int isofs_dentry_cmp_ms(const struct dentry *dentry,
  48                 unsigned int len, const char *str, const struct qstr *name);
  49 #endif
  50 
  51 static void isofs_put_super(struct super_block *sb)
  52 {
  53         struct isofs_sb_info *sbi = ISOFS_SB(sb);
  54 
  55 #ifdef CONFIG_JOLIET
  56         unload_nls(sbi->s_nls_iocharset);
  57 #endif
  58 
  59         kfree(sbi);
  60         sb->s_fs_info = NULL;
  61         return;
  62 }
  63 
  64 static int isofs_read_inode(struct inode *, int relocated);
  65 static int isofs_statfs (struct dentry *, struct kstatfs *);
  66 static int isofs_show_options(struct seq_file *, struct dentry *);
  67 
  68 static struct kmem_cache *isofs_inode_cachep;
  69 
  70 static struct inode *isofs_alloc_inode(struct super_block *sb)
  71 {
  72         struct iso_inode_info *ei;
  73         ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
  74         if (!ei)
  75                 return NULL;
  76         return &ei->vfs_inode;
  77 }
  78 
  79 static void isofs_free_inode(struct inode *inode)
  80 {
  81         kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
  82 }
  83 
  84 static void init_once(void *foo)
  85 {
  86         struct iso_inode_info *ei = foo;
  87 
  88         inode_init_once(&ei->vfs_inode);
  89 }
  90 
  91 static int __init init_inodecache(void)
  92 {
  93         isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
  94                                         sizeof(struct iso_inode_info),
  95                                         0, (SLAB_RECLAIM_ACCOUNT|
  96                                         SLAB_MEM_SPREAD|SLAB_ACCOUNT),
  97                                         init_once);
  98         if (!isofs_inode_cachep)
  99                 return -ENOMEM;
 100         return 0;
 101 }
 102 
 103 static void destroy_inodecache(void)
 104 {
 105         /*
 106          * Make sure all delayed rcu free inodes are flushed before we
 107          * destroy cache.
 108          */
 109         rcu_barrier();
 110         kmem_cache_destroy(isofs_inode_cachep);
 111 }
 112 
 113 static int isofs_remount(struct super_block *sb, int *flags, char *data)
 114 {
 115         sync_filesystem(sb);
 116         if (!(*flags & SB_RDONLY))
 117                 return -EROFS;
 118         return 0;
 119 }
 120 
 121 static const struct super_operations isofs_sops = {
 122         .alloc_inode    = isofs_alloc_inode,
 123         .free_inode     = isofs_free_inode,
 124         .put_super      = isofs_put_super,
 125         .statfs         = isofs_statfs,
 126         .remount_fs     = isofs_remount,
 127         .show_options   = isofs_show_options,
 128 };
 129 
 130 
 131 static const struct dentry_operations isofs_dentry_ops[] = {
 132         {
 133                 .d_hash         = isofs_hashi,
 134                 .d_compare      = isofs_dentry_cmpi,
 135         },
 136 #ifdef CONFIG_JOLIET
 137         {
 138                 .d_hash         = isofs_hash_ms,
 139                 .d_compare      = isofs_dentry_cmp_ms,
 140         },
 141         {
 142                 .d_hash         = isofs_hashi_ms,
 143                 .d_compare      = isofs_dentry_cmpi_ms,
 144         },
 145 #endif
 146 };
 147 
 148 struct iso9660_options{
 149         unsigned int rock:1;
 150         unsigned int joliet:1;
 151         unsigned int cruft:1;
 152         unsigned int hide:1;
 153         unsigned int showassoc:1;
 154         unsigned int nocompress:1;
 155         unsigned int overriderockperm:1;
 156         unsigned int uid_set:1;
 157         unsigned int gid_set:1;
 158         unsigned int utf8:1;
 159         unsigned char map;
 160         unsigned char check;
 161         unsigned int blocksize;
 162         umode_t fmode;
 163         umode_t dmode;
 164         kgid_t gid;
 165         kuid_t uid;
 166         char *iocharset;
 167         /* LVE */
 168         s32 session;
 169         s32 sbsector;
 170 };
 171 
 172 /*
 173  * Compute the hash for the isofs name corresponding to the dentry.
 174  */
 175 static int
 176 isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
 177 {
 178         const char *name;
 179         int len;
 180         char c;
 181         unsigned long hash;
 182 
 183         len = qstr->len;
 184         name = qstr->name;
 185         if (ms) {
 186                 while (len && name[len-1] == '.')
 187                         len--;
 188         }
 189 
 190         hash = init_name_hash(dentry);
 191         while (len--) {
 192                 c = tolower(*name++);
 193                 hash = partial_name_hash(c, hash);
 194         }
 195         qstr->hash = end_name_hash(hash);
 196 
 197         return 0;
 198 }
 199 
 200 /*
 201  * Compare of two isofs names.
 202  */
 203 static int isofs_dentry_cmp_common(
 204                 unsigned int len, const char *str,
 205                 const struct qstr *name, int ms, int ci)
 206 {
 207         int alen, blen;
 208 
 209         /* A filename cannot end in '.' or we treat it like it has none */
 210         alen = name->len;
 211         blen = len;
 212         if (ms) {
 213                 while (alen && name->name[alen-1] == '.')
 214                         alen--;
 215                 while (blen && str[blen-1] == '.')
 216                         blen--;
 217         }
 218         if (alen == blen) {
 219                 if (ci) {
 220                         if (strncasecmp(name->name, str, alen) == 0)
 221                                 return 0;
 222                 } else {
 223                         if (strncmp(name->name, str, alen) == 0)
 224                                 return 0;
 225                 }
 226         }
 227         return 1;
 228 }
 229 
 230 static int
 231 isofs_hashi(const struct dentry *dentry, struct qstr *qstr)
 232 {
 233         return isofs_hashi_common(dentry, qstr, 0);
 234 }
 235 
 236 static int
 237 isofs_dentry_cmpi(const struct dentry *dentry,
 238                 unsigned int len, const char *str, const struct qstr *name)
 239 {
 240         return isofs_dentry_cmp_common(len, str, name, 0, 1);
 241 }
 242 
 243 #ifdef CONFIG_JOLIET
 244 /*
 245  * Compute the hash for the isofs name corresponding to the dentry.
 246  */
 247 static int
 248 isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
 249 {
 250         const char *name;
 251         int len;
 252 
 253         len = qstr->len;
 254         name = qstr->name;
 255         if (ms) {
 256                 while (len && name[len-1] == '.')
 257                         len--;
 258         }
 259 
 260         qstr->hash = full_name_hash(dentry, name, len);
 261 
 262         return 0;
 263 }
 264 
 265 static int
 266 isofs_hash_ms(const struct dentry *dentry, struct qstr *qstr)
 267 {
 268         return isofs_hash_common(dentry, qstr, 1);
 269 }
 270 
 271 static int
 272 isofs_hashi_ms(const struct dentry *dentry, struct qstr *qstr)
 273 {
 274         return isofs_hashi_common(dentry, qstr, 1);
 275 }
 276 
 277 static int
 278 isofs_dentry_cmp_ms(const struct dentry *dentry,
 279                 unsigned int len, const char *str, const struct qstr *name)
 280 {
 281         return isofs_dentry_cmp_common(len, str, name, 1, 0);
 282 }
 283 
 284 static int
 285 isofs_dentry_cmpi_ms(const struct dentry *dentry,
 286                 unsigned int len, const char *str, const struct qstr *name)
 287 {
 288         return isofs_dentry_cmp_common(len, str, name, 1, 1);
 289 }
 290 #endif
 291 
 292 enum {
 293         Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
 294         Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
 295         Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
 296         Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
 297 };
 298 
 299 static const match_table_t tokens = {
 300         {Opt_norock, "norock"},
 301         {Opt_nojoliet, "nojoliet"},
 302         {Opt_unhide, "unhide"},
 303         {Opt_hide, "hide"},
 304         {Opt_showassoc, "showassoc"},
 305         {Opt_cruft, "cruft"},
 306         {Opt_utf8, "utf8"},
 307         {Opt_iocharset, "iocharset=%s"},
 308         {Opt_map_a, "map=acorn"},
 309         {Opt_map_a, "map=a"},
 310         {Opt_map_n, "map=normal"},
 311         {Opt_map_n, "map=n"},
 312         {Opt_map_o, "map=off"},
 313         {Opt_map_o, "map=o"},
 314         {Opt_session, "session=%u"},
 315         {Opt_sb, "sbsector=%u"},
 316         {Opt_check_r, "check=relaxed"},
 317         {Opt_check_r, "check=r"},
 318         {Opt_check_s, "check=strict"},
 319         {Opt_check_s, "check=s"},
 320         {Opt_uid, "uid=%u"},
 321         {Opt_gid, "gid=%u"},
 322         {Opt_mode, "mode=%u"},
 323         {Opt_dmode, "dmode=%u"},
 324         {Opt_overriderockperm, "overriderockperm"},
 325         {Opt_block, "block=%u"},
 326         {Opt_ignore, "conv=binary"},
 327         {Opt_ignore, "conv=b"},
 328         {Opt_ignore, "conv=text"},
 329         {Opt_ignore, "conv=t"},
 330         {Opt_ignore, "conv=mtext"},
 331         {Opt_ignore, "conv=m"},
 332         {Opt_ignore, "conv=auto"},
 333         {Opt_ignore, "conv=a"},
 334         {Opt_nocompress, "nocompress"},
 335         {Opt_err, NULL}
 336 };
 337 
 338 static int parse_options(char *options, struct iso9660_options *popt)
 339 {
 340         char *p;
 341         int option;
 342 
 343         popt->map = 'n';
 344         popt->rock = 1;
 345         popt->joliet = 1;
 346         popt->cruft = 0;
 347         popt->hide = 0;
 348         popt->showassoc = 0;
 349         popt->check = 'u';              /* unset */
 350         popt->nocompress = 0;
 351         popt->blocksize = 1024;
 352         popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
 353         popt->uid_set = 0;
 354         popt->gid_set = 0;
 355         popt->gid = GLOBAL_ROOT_GID;
 356         popt->uid = GLOBAL_ROOT_UID;
 357         popt->iocharset = NULL;
 358         popt->utf8 = 0;
 359         popt->overriderockperm = 0;
 360         popt->session=-1;
 361         popt->sbsector=-1;
 362         if (!options)
 363                 return 1;
 364 
 365         while ((p = strsep(&options, ",")) != NULL) {
 366                 int token;
 367                 substring_t args[MAX_OPT_ARGS];
 368                 unsigned n;
 369 
 370                 if (!*p)
 371                         continue;
 372 
 373                 token = match_token(p, tokens, args);
 374                 switch (token) {
 375                 case Opt_norock:
 376                         popt->rock = 0;
 377                         break;
 378                 case Opt_nojoliet:
 379                         popt->joliet = 0;
 380                         break;
 381                 case Opt_hide:
 382                         popt->hide = 1;
 383                         break;
 384                 case Opt_unhide:
 385                 case Opt_showassoc:
 386                         popt->showassoc = 1;
 387                         break;
 388                 case Opt_cruft:
 389                         popt->cruft = 1;
 390                         break;
 391                 case Opt_utf8:
 392                         popt->utf8 = 1;
 393                         break;
 394 #ifdef CONFIG_JOLIET
 395                 case Opt_iocharset:
 396                         kfree(popt->iocharset);
 397                         popt->iocharset = match_strdup(&args[0]);
 398                         if (!popt->iocharset)
 399                                 return 0;
 400                         break;
 401 #endif
 402                 case Opt_map_a:
 403                         popt->map = 'a';
 404                         break;
 405                 case Opt_map_o:
 406                         popt->map = 'o';
 407                         break;
 408                 case Opt_map_n:
 409                         popt->map = 'n';
 410                         break;
 411                 case Opt_session:
 412                         if (match_int(&args[0], &option))
 413                                 return 0;
 414                         n = option;
 415                         /*
 416                          * Track numbers are supposed to be in range 1-99, the
 417                          * mount option starts indexing at 0.
 418                          */
 419                         if (n >= 99)
 420                                 return 0;
 421                         popt->session = n + 1;
 422                         break;
 423                 case Opt_sb:
 424                         if (match_int(&args[0], &option))
 425                                 return 0;
 426                         popt->sbsector = option;
 427                         break;
 428                 case Opt_check_r:
 429                         popt->check = 'r';
 430                         break;
 431                 case Opt_check_s:
 432                         popt->check = 's';
 433                         break;
 434                 case Opt_ignore:
 435                         break;
 436                 case Opt_uid:
 437                         if (match_int(&args[0], &option))
 438                                 return 0;
 439                         popt->uid = make_kuid(current_user_ns(), option);
 440                         if (!uid_valid(popt->uid))
 441                                 return 0;
 442                         popt->uid_set = 1;
 443                         break;
 444                 case Opt_gid:
 445                         if (match_int(&args[0], &option))
 446                                 return 0;
 447                         popt->gid = make_kgid(current_user_ns(), option);
 448                         if (!gid_valid(popt->gid))
 449                                 return 0;
 450                         popt->gid_set = 1;
 451                         break;
 452                 case Opt_mode:
 453                         if (match_int(&args[0], &option))
 454                                 return 0;
 455                         popt->fmode = option;
 456                         break;
 457                 case Opt_dmode:
 458                         if (match_int(&args[0], &option))
 459                                 return 0;
 460                         popt->dmode = option;
 461                         break;
 462                 case Opt_overriderockperm:
 463                         popt->overriderockperm = 1;
 464                         break;
 465                 case Opt_block:
 466                         if (match_int(&args[0], &option))
 467                                 return 0;
 468                         n = option;
 469                         if (n != 512 && n != 1024 && n != 2048)
 470                                 return 0;
 471                         popt->blocksize = n;
 472                         break;
 473                 case Opt_nocompress:
 474                         popt->nocompress = 1;
 475                         break;
 476                 default:
 477                         return 0;
 478                 }
 479         }
 480         return 1;
 481 }
 482 
 483 /*
 484  * Display the mount options in /proc/mounts.
 485  */
 486 static int isofs_show_options(struct seq_file *m, struct dentry *root)
 487 {
 488         struct isofs_sb_info *sbi = ISOFS_SB(root->d_sb);
 489 
 490         if (!sbi->s_rock)               seq_puts(m, ",norock");
 491         else if (!sbi->s_joliet_level)  seq_puts(m, ",nojoliet");
 492         if (sbi->s_cruft)               seq_puts(m, ",cruft");
 493         if (sbi->s_hide)                seq_puts(m, ",hide");
 494         if (sbi->s_nocompress)          seq_puts(m, ",nocompress");
 495         if (sbi->s_overriderockperm)    seq_puts(m, ",overriderockperm");
 496         if (sbi->s_showassoc)           seq_puts(m, ",showassoc");
 497         if (sbi->s_utf8)                seq_puts(m, ",utf8");
 498 
 499         if (sbi->s_check)               seq_printf(m, ",check=%c", sbi->s_check);
 500         if (sbi->s_mapping)             seq_printf(m, ",map=%c", sbi->s_mapping);
 501         if (sbi->s_session != 255)      seq_printf(m, ",session=%u", sbi->s_session - 1);
 502         if (sbi->s_sbsector != -1)      seq_printf(m, ",sbsector=%u", sbi->s_sbsector);
 503 
 504         if (root->d_sb->s_blocksize != 1024)
 505                 seq_printf(m, ",blocksize=%lu", root->d_sb->s_blocksize);
 506 
 507         if (sbi->s_uid_set)
 508                 seq_printf(m, ",uid=%u",
 509                            from_kuid_munged(&init_user_ns, sbi->s_uid));
 510         if (sbi->s_gid_set)
 511                 seq_printf(m, ",gid=%u",
 512                            from_kgid_munged(&init_user_ns, sbi->s_gid));
 513 
 514         if (sbi->s_dmode != ISOFS_INVALID_MODE)
 515                 seq_printf(m, ",dmode=%o", sbi->s_dmode);
 516         if (sbi->s_fmode != ISOFS_INVALID_MODE)
 517                 seq_printf(m, ",fmode=%o", sbi->s_fmode);
 518 
 519 #ifdef CONFIG_JOLIET
 520         if (sbi->s_nls_iocharset &&
 521             strcmp(sbi->s_nls_iocharset->charset, CONFIG_NLS_DEFAULT) != 0)
 522                 seq_printf(m, ",iocharset=%s", sbi->s_nls_iocharset->charset);
 523 #endif
 524         return 0;
 525 }
 526 
 527 /*
 528  * look if the driver can tell the multi session redirection value
 529  *
 530  * don't change this if you don't know what you do, please!
 531  * Multisession is legal only with XA disks.
 532  * A non-XA disk with more than one volume descriptor may do it right, but
 533  * usually is written in a nowhere standardized "multi-partition" manner.
 534  * Multisession uses absolute addressing (solely the first frame of the whole
 535  * track is #0), multi-partition uses relative addressing (each first frame of
 536  * each track is #0), and a track is not a session.
 537  *
 538  * A broken CDwriter software or drive firmware does not set new standards,
 539  * at least not if conflicting with the existing ones.
 540  *
 541  * emoenke@gwdg.de
 542  */
 543 #define WE_OBEY_THE_WRITTEN_STANDARDS 1
 544 
 545 static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
 546 {
 547         struct cdrom_multisession ms_info;
 548         unsigned int vol_desc_start;
 549         struct block_device *bdev = sb->s_bdev;
 550         int i;
 551 
 552         vol_desc_start=0;
 553         ms_info.addr_format=CDROM_LBA;
 554         if (session > 0) {
 555                 struct cdrom_tocentry Te;
 556                 Te.cdte_track=session;
 557                 Te.cdte_format=CDROM_LBA;
 558                 i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
 559                 if (!i) {
 560                         printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
 561                                 session, Te.cdte_addr.lba,
 562                                 Te.cdte_ctrl&CDROM_DATA_TRACK);
 563                         if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
 564                                 return Te.cdte_addr.lba;
 565                 }
 566 
 567                 printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
 568         }
 569         i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
 570         if (session > 0)
 571                 printk(KERN_ERR "ISOFS: Invalid session number\n");
 572 #if 0
 573         printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
 574         if (i==0) {
 575                 printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
 576                 printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
 577         }
 578 #endif
 579         if (i==0)
 580 #if WE_OBEY_THE_WRITTEN_STANDARDS
 581                 if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
 582 #endif
 583                         vol_desc_start=ms_info.addr.lba;
 584         return vol_desc_start;
 585 }
 586 
 587 /*
 588  * Check if root directory is empty (has less than 3 files).
 589  *
 590  * Used to detect broken CDs where ISO root directory is empty but Joliet root
 591  * directory is OK. If such CD has Rock Ridge extensions, they will be disabled
 592  * (and Joliet used instead) or else no files would be visible.
 593  */
 594 static bool rootdir_empty(struct super_block *sb, unsigned long block)
 595 {
 596         int offset = 0, files = 0, de_len;
 597         struct iso_directory_record *de;
 598         struct buffer_head *bh;
 599 
 600         bh = sb_bread(sb, block);
 601         if (!bh)
 602                 return true;
 603         while (files < 3) {
 604                 de = (struct iso_directory_record *) (bh->b_data + offset);
 605                 de_len = *(unsigned char *) de;
 606                 if (de_len == 0)
 607                         break;
 608                 files++;
 609                 offset += de_len;
 610         }
 611         brelse(bh);
 612         return files < 3;
 613 }
 614 
 615 /*
 616  * Initialize the superblock and read the root inode.
 617  *
 618  * Note: a check_disk_change() has been done immediately prior
 619  * to this call, so we don't need to check again.
 620  */
 621 static int isofs_fill_super(struct super_block *s, void *data, int silent)
 622 {
 623         struct buffer_head *bh = NULL, *pri_bh = NULL;
 624         struct hs_primary_descriptor *h_pri = NULL;
 625         struct iso_primary_descriptor *pri = NULL;
 626         struct iso_supplementary_descriptor *sec = NULL;
 627         struct iso_directory_record *rootp;
 628         struct inode *inode;
 629         struct iso9660_options opt;
 630         struct isofs_sb_info *sbi;
 631         unsigned long first_data_zone;
 632         int joliet_level = 0;
 633         int iso_blknum, block;
 634         int orig_zonesize;
 635         int table, error = -EINVAL;
 636         unsigned int vol_desc_start;
 637 
 638         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 639         if (!sbi)
 640                 return -ENOMEM;
 641         s->s_fs_info = sbi;
 642 
 643         if (!parse_options((char *)data, &opt))
 644                 goto out_freesbi;
 645 
 646         /*
 647          * First of all, get the hardware blocksize for this device.
 648          * If we don't know what it is, or the hardware blocksize is
 649          * larger than the blocksize the user specified, then use
 650          * that value.
 651          */
 652         /*
 653          * What if bugger tells us to go beyond page size?
 654          */
 655         if (bdev_logical_block_size(s->s_bdev) > 2048) {
 656                 printk(KERN_WARNING
 657                        "ISOFS: unsupported/invalid hardware sector size %d\n",
 658                         bdev_logical_block_size(s->s_bdev));
 659                 goto out_freesbi;
 660         }
 661         opt.blocksize = sb_min_blocksize(s, opt.blocksize);
 662 
 663         sbi->s_high_sierra = 0; /* default is iso9660 */
 664         sbi->s_session = opt.session;
 665         sbi->s_sbsector = opt.sbsector;
 666 
 667         vol_desc_start = (opt.sbsector != -1) ?
 668                 opt.sbsector : isofs_get_last_session(s,opt.session);
 669 
 670         for (iso_blknum = vol_desc_start+16;
 671                 iso_blknum < vol_desc_start+100; iso_blknum++) {
 672                 struct hs_volume_descriptor *hdp;
 673                 struct iso_volume_descriptor  *vdp;
 674 
 675                 block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
 676                 if (!(bh = sb_bread(s, block)))
 677                         goto out_no_read;
 678 
 679                 vdp = (struct iso_volume_descriptor *)bh->b_data;
 680                 hdp = (struct hs_volume_descriptor *)bh->b_data;
 681 
 682                 /*
 683                  * Due to the overlapping physical location of the descriptors,
 684                  * ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
 685                  * proper identification in this case, we first check for ISO.
 686                  */
 687                 if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
 688                         if (isonum_711(vdp->type) == ISO_VD_END)
 689                                 break;
 690                         if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
 691                                 if (!pri) {
 692                                         pri = (struct iso_primary_descriptor *)vdp;
 693                                         /* Save the buffer in case we need it ... */
 694                                         pri_bh = bh;
 695                                         bh = NULL;
 696                                 }
 697                         }
 698 #ifdef CONFIG_JOLIET
 699                         else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
 700                                 sec = (struct iso_supplementary_descriptor *)vdp;
 701                                 if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
 702                                         if (opt.joliet) {
 703                                                 if (sec->escape[2] == 0x40)
 704                                                         joliet_level = 1;
 705                                                 else if (sec->escape[2] == 0x43)
 706                                                         joliet_level = 2;
 707                                                 else if (sec->escape[2] == 0x45)
 708                                                         joliet_level = 3;
 709 
 710                                                 printk(KERN_DEBUG "ISO 9660 Extensions: "
 711                                                         "Microsoft Joliet Level %d\n",
 712                                                         joliet_level);
 713                                         }
 714                                         goto root_found;
 715                                 } else {
 716                                 /* Unknown supplementary volume descriptor */
 717                                 sec = NULL;
 718                                 }
 719                         }
 720 #endif
 721                 } else {
 722                         if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
 723                                 if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
 724                                         goto out_freebh;
 725 
 726                                 sbi->s_high_sierra = 1;
 727                                 opt.rock = 0;
 728                                 h_pri = (struct hs_primary_descriptor *)vdp;
 729                                 goto root_found;
 730                         }
 731                 }
 732 
 733                 /* Just skip any volume descriptors we don't recognize */
 734 
 735                 brelse(bh);
 736                 bh = NULL;
 737         }
 738         /*
 739          * If we fall through, either no volume descriptor was found,
 740          * or else we passed a primary descriptor looking for others.
 741          */
 742         if (!pri)
 743                 goto out_unknown_format;
 744         brelse(bh);
 745         bh = pri_bh;
 746         pri_bh = NULL;
 747 
 748 root_found:
 749         /* We don't support read-write mounts */
 750         if (!sb_rdonly(s)) {
 751                 error = -EACCES;
 752                 goto out_freebh;
 753         }
 754 
 755         if (joliet_level && (!pri || !opt.rock)) {
 756                 /* This is the case of Joliet with the norock mount flag.
 757                  * A disc with both Joliet and Rock Ridge is handled later
 758                  */
 759                 pri = (struct iso_primary_descriptor *) sec;
 760         }
 761 
 762         if(sbi->s_high_sierra){
 763                 rootp = (struct iso_directory_record *) h_pri->root_directory_record;
 764                 sbi->s_nzones = isonum_733(h_pri->volume_space_size);
 765                 sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
 766                 sbi->s_max_size = isonum_733(h_pri->volume_space_size);
 767         } else {
 768                 if (!pri)
 769                         goto out_freebh;
 770                 rootp = (struct iso_directory_record *) pri->root_directory_record;
 771                 sbi->s_nzones = isonum_733(pri->volume_space_size);
 772                 sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
 773                 sbi->s_max_size = isonum_733(pri->volume_space_size);
 774         }
 775 
 776         sbi->s_ninodes = 0; /* No way to figure this out easily */
 777 
 778         orig_zonesize = sbi->s_log_zone_size;
 779         /*
 780          * If the zone size is smaller than the hardware sector size,
 781          * this is a fatal error.  This would occur if the disc drive
 782          * had sectors that were 2048 bytes, but the filesystem had
 783          * blocks that were 512 bytes (which should only very rarely
 784          * happen.)
 785          */
 786         if (orig_zonesize < opt.blocksize)
 787                 goto out_bad_size;
 788 
 789         /* RDE: convert log zone size to bit shift */
 790         switch (sbi->s_log_zone_size) {
 791         case  512: sbi->s_log_zone_size =  9; break;
 792         case 1024: sbi->s_log_zone_size = 10; break;
 793         case 2048: sbi->s_log_zone_size = 11; break;
 794 
 795         default:
 796                 goto out_bad_zone_size;
 797         }
 798 
 799         s->s_magic = ISOFS_SUPER_MAGIC;
 800 
 801         /*
 802          * With multi-extent files, file size is only limited by the maximum
 803          * size of a file system, which is 8 TB.
 804          */
 805         s->s_maxbytes = 0x80000000000LL;
 806 
 807         /* ECMA-119 timestamp from 1900/1/1 with tz offset */
 808         s->s_time_min = mktime64(1900, 1, 1, 0, 0, 0) - MAX_TZ_OFFSET;
 809         s->s_time_max = mktime64(U8_MAX+1900, 12, 31, 23, 59, 59) + MAX_TZ_OFFSET;
 810 
 811         /* Set this for reference. Its not currently used except on write
 812            which we don't have .. */
 813 
 814         first_data_zone = isonum_733(rootp->extent) +
 815                           isonum_711(rootp->ext_attr_length);
 816         sbi->s_firstdatazone = first_data_zone;
 817 #ifndef BEQUIET
 818         printk(KERN_DEBUG "ISOFS: Max size:%ld   Log zone size:%ld\n",
 819                 sbi->s_max_size, 1UL << sbi->s_log_zone_size);
 820         printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
 821         if(sbi->s_high_sierra)
 822                 printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
 823 #endif
 824 
 825         /*
 826          * If the Joliet level is set, we _may_ decide to use the
 827          * secondary descriptor, but can't be sure until after we
 828          * read the root inode. But before reading the root inode
 829          * we may need to change the device blocksize, and would
 830          * rather release the old buffer first. So, we cache the
 831          * first_data_zone value from the secondary descriptor.
 832          */
 833         if (joliet_level) {
 834                 pri = (struct iso_primary_descriptor *) sec;
 835                 rootp = (struct iso_directory_record *)
 836                         pri->root_directory_record;
 837                 first_data_zone = isonum_733(rootp->extent) +
 838                                 isonum_711(rootp->ext_attr_length);
 839         }
 840 
 841         /*
 842          * We're all done using the volume descriptor, and may need
 843          * to change the device blocksize, so release the buffer now.
 844          */
 845         brelse(pri_bh);
 846         brelse(bh);
 847 
 848         /*
 849          * Force the blocksize to 512 for 512 byte sectors.  The file
 850          * read primitives really get it wrong in a bad way if we don't
 851          * do this.
 852          *
 853          * Note - we should never be setting the blocksize to something
 854          * less than the hardware sector size for the device.  If we
 855          * do, we would end up having to read larger buffers and split
 856          * out portions to satisfy requests.
 857          *
 858          * Note2- the idea here is that we want to deal with the optimal
 859          * zonesize in the filesystem.  If we have it set to something less,
 860          * then we have horrible problems with trying to piece together
 861          * bits of adjacent blocks in order to properly read directory
 862          * entries.  By forcing the blocksize in this way, we ensure
 863          * that we will never be required to do this.
 864          */
 865         sb_set_blocksize(s, orig_zonesize);
 866 
 867         sbi->s_nls_iocharset = NULL;
 868 
 869 #ifdef CONFIG_JOLIET
 870         if (joliet_level && opt.utf8 == 0) {
 871                 char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
 872                 sbi->s_nls_iocharset = load_nls(p);
 873                 if (! sbi->s_nls_iocharset) {
 874                         /* Fail only if explicit charset specified */
 875                         if (opt.iocharset)
 876                                 goto out_freesbi;
 877                         sbi->s_nls_iocharset = load_nls_default();
 878                 }
 879         }
 880 #endif
 881         s->s_op = &isofs_sops;
 882         s->s_export_op = &isofs_export_ops;
 883         sbi->s_mapping = opt.map;
 884         sbi->s_rock = (opt.rock ? 2 : 0);
 885         sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
 886         sbi->s_cruft = opt.cruft;
 887         sbi->s_hide = opt.hide;
 888         sbi->s_showassoc = opt.showassoc;
 889         sbi->s_uid = opt.uid;
 890         sbi->s_gid = opt.gid;
 891         sbi->s_uid_set = opt.uid_set;
 892         sbi->s_gid_set = opt.gid_set;
 893         sbi->s_utf8 = opt.utf8;
 894         sbi->s_nocompress = opt.nocompress;
 895         sbi->s_overriderockperm = opt.overriderockperm;
 896         /*
 897          * It would be incredibly stupid to allow people to mark every file
 898          * on the disk as suid, so we merely allow them to set the default
 899          * permissions.
 900          */
 901         if (opt.fmode != ISOFS_INVALID_MODE)
 902                 sbi->s_fmode = opt.fmode & 0777;
 903         else
 904                 sbi->s_fmode = ISOFS_INVALID_MODE;
 905         if (opt.dmode != ISOFS_INVALID_MODE)
 906                 sbi->s_dmode = opt.dmode & 0777;
 907         else
 908                 sbi->s_dmode = ISOFS_INVALID_MODE;
 909 
 910         /*
 911          * Read the root inode, which _may_ result in changing
 912          * the s_rock flag. Once we have the final s_rock value,
 913          * we then decide whether to use the Joliet descriptor.
 914          */
 915         inode = isofs_iget(s, sbi->s_firstdatazone, 0);
 916         if (IS_ERR(inode))
 917                 goto out_no_root;
 918 
 919         /*
 920          * Fix for broken CDs with Rock Ridge and empty ISO root directory but
 921          * correct Joliet root directory.
 922          */
 923         if (sbi->s_rock == 1 && joliet_level &&
 924                                 rootdir_empty(s, sbi->s_firstdatazone)) {
 925                 printk(KERN_NOTICE
 926                         "ISOFS: primary root directory is empty. "
 927                         "Disabling Rock Ridge and switching to Joliet.");
 928                 sbi->s_rock = 0;
 929         }
 930 
 931         /*
 932          * If this disk has both Rock Ridge and Joliet on it, then we
 933          * want to use Rock Ridge by default.  This can be overridden
 934          * by using the norock mount option.  There is still one other
 935          * possibility that is not taken into account: a Rock Ridge
 936          * CD with Unicode names.  Until someone sees such a beast, it
 937          * will not be supported.
 938          */
 939         if (sbi->s_rock == 1) {
 940                 joliet_level = 0;
 941         } else if (joliet_level) {
 942                 sbi->s_rock = 0;
 943                 if (sbi->s_firstdatazone != first_data_zone) {
 944                         sbi->s_firstdatazone = first_data_zone;
 945                         printk(KERN_DEBUG
 946                                 "ISOFS: changing to secondary root\n");
 947                         iput(inode);
 948                         inode = isofs_iget(s, sbi->s_firstdatazone, 0);
 949                         if (IS_ERR(inode))
 950                                 goto out_no_root;
 951                 }
 952         }
 953 
 954         if (opt.check == 'u') {
 955                 /* Only Joliet is case insensitive by default */
 956                 if (joliet_level)
 957                         opt.check = 'r';
 958                 else
 959                         opt.check = 's';
 960         }
 961         sbi->s_joliet_level = joliet_level;
 962 
 963         /* Make sure the root inode is a directory */
 964         if (!S_ISDIR(inode->i_mode)) {
 965                 printk(KERN_WARNING
 966                         "isofs_fill_super: root inode is not a directory. "
 967                         "Corrupted media?\n");
 968                 goto out_iput;
 969         }
 970 
 971         table = 0;
 972         if (joliet_level)
 973                 table += 2;
 974         if (opt.check == 'r')
 975                 table++;
 976         sbi->s_check = opt.check;
 977 
 978         if (table)
 979                 s->s_d_op = &isofs_dentry_ops[table - 1];
 980 
 981         /* get the root dentry */
 982         s->s_root = d_make_root(inode);
 983         if (!(s->s_root)) {
 984                 error = -ENOMEM;
 985                 goto out_no_inode;
 986         }
 987 
 988         kfree(opt.iocharset);
 989 
 990         return 0;
 991 
 992         /*
 993          * Display error messages and free resources.
 994          */
 995 out_iput:
 996         iput(inode);
 997         goto out_no_inode;
 998 out_no_root:
 999         error = PTR_ERR(inode);
1000         if (error != -ENOMEM)
1001                 printk(KERN_WARNING "%s: get root inode failed\n", __func__);
1002 out_no_inode:
1003 #ifdef CONFIG_JOLIET
1004         unload_nls(sbi->s_nls_iocharset);
1005 #endif
1006         goto out_freesbi;
1007 out_no_read:
1008         printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
1009                 __func__, s->s_id, iso_blknum, block);
1010         goto out_freebh;
1011 out_bad_zone_size:
1012         printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
1013                 sbi->s_log_zone_size);
1014         goto out_freebh;
1015 out_bad_size:
1016         printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
1017                 orig_zonesize, opt.blocksize);
1018         goto out_freebh;
1019 out_unknown_format:
1020         if (!silent)
1021                 printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
1022 
1023 out_freebh:
1024         brelse(bh);
1025         brelse(pri_bh);
1026 out_freesbi:
1027         kfree(opt.iocharset);
1028         kfree(sbi);
1029         s->s_fs_info = NULL;
1030         return error;
1031 }
1032 
1033 static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
1034 {
1035         struct super_block *sb = dentry->d_sb;
1036         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1037 
1038         buf->f_type = ISOFS_SUPER_MAGIC;
1039         buf->f_bsize = sb->s_blocksize;
1040         buf->f_blocks = (ISOFS_SB(sb)->s_nzones
1041                 << (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
1042         buf->f_bfree = 0;
1043         buf->f_bavail = 0;
1044         buf->f_files = ISOFS_SB(sb)->s_ninodes;
1045         buf->f_ffree = 0;
1046         buf->f_fsid.val[0] = (u32)id;
1047         buf->f_fsid.val[1] = (u32)(id >> 32);
1048         buf->f_namelen = NAME_MAX;
1049         return 0;
1050 }
1051 
1052 /*
1053  * Get a set of blocks; filling in buffer_heads if already allocated
1054  * or getblk() if they are not.  Returns the number of blocks inserted
1055  * (-ve == error.)
1056  */
1057 int isofs_get_blocks(struct inode *inode, sector_t iblock,
1058                      struct buffer_head **bh, unsigned long nblocks)
1059 {
1060         unsigned long b_off = iblock;
1061         unsigned offset, sect_size;
1062         unsigned int firstext;
1063         unsigned long nextblk, nextoff;
1064         int section, rv, error;
1065         struct iso_inode_info *ei = ISOFS_I(inode);
1066 
1067         error = -EIO;
1068         rv = 0;
1069         if (iblock != b_off) {
1070                 printk(KERN_DEBUG "%s: block number too large\n", __func__);
1071                 goto abort;
1072         }
1073 
1074 
1075         offset = 0;
1076         firstext = ei->i_first_extent;
1077         sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
1078         nextblk = ei->i_next_section_block;
1079         nextoff = ei->i_next_section_offset;
1080         section = 0;
1081 
1082         while (nblocks) {
1083                 /* If we are *way* beyond the end of the file, print a message.
1084                  * Access beyond the end of the file up to the next page boundary
1085                  * is normal, however because of the way the page cache works.
1086                  * In this case, we just return 0 so that we can properly fill
1087                  * the page with useless information without generating any
1088                  * I/O errors.
1089                  */
1090                 if (b_off > ((inode->i_size + PAGE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
1091                         printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
1092                                 __func__, b_off,
1093                                 (unsigned long long)inode->i_size);
1094                         goto abort;
1095                 }
1096 
1097                 /* On the last section, nextblk == 0, section size is likely to
1098                  * exceed sect_size by a partial block, and access beyond the
1099                  * end of the file will reach beyond the section size, too.
1100                  */
1101                 while (nextblk && (b_off >= (offset + sect_size))) {
1102                         struct inode *ninode;
1103 
1104                         offset += sect_size;
1105                         ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
1106                         if (IS_ERR(ninode)) {
1107                                 error = PTR_ERR(ninode);
1108                                 goto abort;
1109                         }
1110                         firstext  = ISOFS_I(ninode)->i_first_extent;
1111                         sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
1112                         nextblk   = ISOFS_I(ninode)->i_next_section_block;
1113                         nextoff   = ISOFS_I(ninode)->i_next_section_offset;
1114                         iput(ninode);
1115 
1116                         if (++section > 100) {
1117                                 printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
1118                                         " aborting...\n", __func__);
1119                                 printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
1120                                         "nextblk=%lu nextoff=%lu\n", __func__,
1121                                         b_off, firstext, (unsigned) sect_size,
1122                                         nextblk, nextoff);
1123                                 goto abort;
1124                         }
1125                 }
1126 
1127                 if (*bh) {
1128                         map_bh(*bh, inode->i_sb, firstext + b_off - offset);
1129                 } else {
1130                         *bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
1131                         if (!*bh)
1132                                 goto abort;
1133                 }
1134                 bh++;   /* Next buffer head */
1135                 b_off++;        /* Next buffer offset */
1136                 nblocks--;
1137                 rv++;
1138         }
1139 
1140         error = 0;
1141 abort:
1142         return rv != 0 ? rv : error;
1143 }
1144 
1145 /*
1146  * Used by the standard interfaces.
1147  */
1148 static int isofs_get_block(struct inode *inode, sector_t iblock,
1149                     struct buffer_head *bh_result, int create)
1150 {
1151         int ret;
1152 
1153         if (create) {
1154                 printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
1155                 return -EROFS;
1156         }
1157 
1158         ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
1159         return ret < 0 ? ret : 0;
1160 }
1161 
1162 static int isofs_bmap(struct inode *inode, sector_t block)
1163 {
1164         struct buffer_head dummy;
1165         int error;
1166 
1167         dummy.b_state = 0;
1168         dummy.b_blocknr = -1000;
1169         error = isofs_get_block(inode, block, &dummy, 0);
1170         if (!error)
1171                 return dummy.b_blocknr;
1172         return 0;
1173 }
1174 
1175 struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
1176 {
1177         sector_t blknr = isofs_bmap(inode, block);
1178         if (!blknr)
1179                 return NULL;
1180         return sb_bread(inode->i_sb, blknr);
1181 }
1182 
1183 static int isofs_readpage(struct file *file, struct page *page)
1184 {
1185         return mpage_readpage(page, isofs_get_block);
1186 }
1187 
1188 static int isofs_readpages(struct file *file, struct address_space *mapping,
1189                         struct list_head *pages, unsigned nr_pages)
1190 {
1191         return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
1192 }
1193 
1194 static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
1195 {
1196         return generic_block_bmap(mapping,block,isofs_get_block);
1197 }
1198 
1199 static const struct address_space_operations isofs_aops = {
1200         .readpage = isofs_readpage,
1201         .readpages = isofs_readpages,
1202         .bmap = _isofs_bmap
1203 };
1204 
1205 static int isofs_read_level3_size(struct inode *inode)
1206 {
1207         unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1208         int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
1209         struct buffer_head *bh = NULL;
1210         unsigned long block, offset, block_saved, offset_saved;
1211         int i = 0;
1212         int more_entries = 0;
1213         struct iso_directory_record *tmpde = NULL;
1214         struct iso_inode_info *ei = ISOFS_I(inode);
1215 
1216         inode->i_size = 0;
1217 
1218         /* The first 16 blocks are reserved as the System Area.  Thus,
1219          * no inodes can appear in block 0.  We use this to flag that
1220          * this is the last section. */
1221         ei->i_next_section_block = 0;
1222         ei->i_next_section_offset = 0;
1223 
1224         block = ei->i_iget5_block;
1225         offset = ei->i_iget5_offset;
1226 
1227         do {
1228                 struct iso_directory_record *de;
1229                 unsigned int de_len;
1230 
1231                 if (!bh) {
1232                         bh = sb_bread(inode->i_sb, block);
1233                         if (!bh)
1234                                 goto out_noread;
1235                 }
1236                 de = (struct iso_directory_record *) (bh->b_data + offset);
1237                 de_len = *(unsigned char *) de;
1238 
1239                 if (de_len == 0) {
1240                         brelse(bh);
1241                         bh = NULL;
1242                         ++block;
1243                         offset = 0;
1244                         continue;
1245                 }
1246 
1247                 block_saved = block;
1248                 offset_saved = offset;
1249                 offset += de_len;
1250 
1251                 /* Make sure we have a full directory entry */
1252                 if (offset >= bufsize) {
1253                         int slop = bufsize - offset + de_len;
1254                         if (!tmpde) {
1255                                 tmpde = kmalloc(256, GFP_KERNEL);
1256                                 if (!tmpde)
1257                                         goto out_nomem;
1258                         }
1259                         memcpy(tmpde, de, slop);
1260                         offset &= bufsize - 1;
1261                         block++;
1262                         brelse(bh);
1263                         bh = NULL;
1264                         if (offset) {
1265                                 bh = sb_bread(inode->i_sb, block);
1266                                 if (!bh)
1267                                         goto out_noread;
1268                                 memcpy((void *)tmpde+slop, bh->b_data, offset);
1269                         }
1270                         de = tmpde;
1271                 }
1272 
1273                 inode->i_size += isonum_733(de->size);
1274                 if (i == 1) {
1275                         ei->i_next_section_block = block_saved;
1276                         ei->i_next_section_offset = offset_saved;
1277                 }
1278 
1279                 more_entries = de->flags[-high_sierra] & 0x80;
1280 
1281                 i++;
1282                 if (i > 100)
1283                         goto out_toomany;
1284         } while (more_entries);
1285 out:
1286         kfree(tmpde);
1287         if (bh)
1288                 brelse(bh);
1289         return 0;
1290 
1291 out_nomem:
1292         if (bh)
1293                 brelse(bh);
1294         return -ENOMEM;
1295 
1296 out_noread:
1297         printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
1298         kfree(tmpde);
1299         return -EIO;
1300 
1301 out_toomany:
1302         printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
1303                 "isofs_read_level3_size: inode=%lu\n",
1304                 __func__, inode->i_ino);
1305         goto out;
1306 }
1307 
1308 static int isofs_read_inode(struct inode *inode, int relocated)
1309 {
1310         struct super_block *sb = inode->i_sb;
1311         struct isofs_sb_info *sbi = ISOFS_SB(sb);
1312         unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
1313         unsigned long block;
1314         int high_sierra = sbi->s_high_sierra;
1315         struct buffer_head *bh;
1316         struct iso_directory_record *de;
1317         struct iso_directory_record *tmpde = NULL;
1318         unsigned int de_len;
1319         unsigned long offset;
1320         struct iso_inode_info *ei = ISOFS_I(inode);
1321         int ret = -EIO;
1322 
1323         block = ei->i_iget5_block;
1324         bh = sb_bread(inode->i_sb, block);
1325         if (!bh)
1326                 goto out_badread;
1327 
1328         offset = ei->i_iget5_offset;
1329 
1330         de = (struct iso_directory_record *) (bh->b_data + offset);
1331         de_len = *(unsigned char *) de;
1332 
1333         if (offset + de_len > bufsize) {
1334                 int frag1 = bufsize - offset;
1335 
1336                 tmpde = kmalloc(de_len, GFP_KERNEL);
1337                 if (!tmpde) {
1338                         ret = -ENOMEM;
1339                         goto fail;
1340                 }
1341                 memcpy(tmpde, bh->b_data + offset, frag1);
1342                 brelse(bh);
1343                 bh = sb_bread(inode->i_sb, ++block);
1344                 if (!bh)
1345                         goto out_badread;
1346                 memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
1347                 de = tmpde;
1348         }
1349 
1350         inode->i_ino = isofs_get_ino(ei->i_iget5_block,
1351                                         ei->i_iget5_offset,
1352                                         ISOFS_BUFFER_BITS(inode));
1353 
1354         /* Assume it is a normal-format file unless told otherwise */
1355         ei->i_file_format = isofs_file_normal;
1356 
1357         if (de->flags[-high_sierra] & 2) {
1358                 if (sbi->s_dmode != ISOFS_INVALID_MODE)
1359                         inode->i_mode = S_IFDIR | sbi->s_dmode;
1360                 else
1361                         inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
1362                 set_nlink(inode, 1);    /*
1363                                          * Set to 1.  We know there are 2, but
1364                                          * the find utility tries to optimize
1365                                          * if it is 2, and it screws up.  It is
1366                                          * easier to give 1 which tells find to
1367                                          * do it the hard way.
1368                                          */
1369         } else {
1370                 if (sbi->s_fmode != ISOFS_INVALID_MODE) {
1371                         inode->i_mode = S_IFREG | sbi->s_fmode;
1372                 } else {
1373                         /*
1374                          * Set default permissions: r-x for all.  The disc
1375                          * could be shared with DOS machines so virtually
1376                          * anything could be a valid executable.
1377                          */
1378                         inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
1379                 }
1380                 set_nlink(inode, 1);
1381         }
1382         inode->i_uid = sbi->s_uid;
1383         inode->i_gid = sbi->s_gid;
1384         inode->i_blocks = 0;
1385 
1386         ei->i_format_parm[0] = 0;
1387         ei->i_format_parm[1] = 0;
1388         ei->i_format_parm[2] = 0;
1389 
1390         ei->i_section_size = isonum_733(de->size);
1391         if (de->flags[-high_sierra] & 0x80) {
1392                 ret = isofs_read_level3_size(inode);
1393                 if (ret < 0)
1394                         goto fail;
1395                 ret = -EIO;
1396         } else {
1397                 ei->i_next_section_block = 0;
1398                 ei->i_next_section_offset = 0;
1399                 inode->i_size = isonum_733(de->size);
1400         }
1401 
1402         /*
1403          * Some dipshit decided to store some other bit of information
1404          * in the high byte of the file length.  Truncate size in case
1405          * this CDROM was mounted with the cruft option.
1406          */
1407 
1408         if (sbi->s_cruft)
1409                 inode->i_size &= 0x00ffffff;
1410 
1411         if (de->interleave[0]) {
1412                 printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
1413                 inode->i_size = 0;
1414         }
1415 
1416         /* I have no idea what file_unit_size is used for, so
1417            we will flag it for now */
1418         if (de->file_unit_size[0] != 0) {
1419                 printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
1420                         inode->i_ino);
1421         }
1422 
1423         /* I have no idea what other flag bits are used for, so
1424            we will flag it for now */
1425 #ifdef DEBUG
1426         if((de->flags[-high_sierra] & ~2)!= 0){
1427                 printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
1428                                 "(%ld %x).\n",
1429                         inode->i_ino, de->flags[-high_sierra]);
1430         }
1431 #endif
1432 
1433         inode->i_mtime.tv_sec =
1434         inode->i_atime.tv_sec =
1435         inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
1436         inode->i_mtime.tv_nsec =
1437         inode->i_atime.tv_nsec =
1438         inode->i_ctime.tv_nsec = 0;
1439 
1440         ei->i_first_extent = (isonum_733(de->extent) +
1441                         isonum_711(de->ext_attr_length));
1442 
1443         /* Set the number of blocks for stat() - should be done before RR */
1444         inode->i_blocks = (inode->i_size + 511) >> 9;
1445 
1446         /*
1447          * Now test for possible Rock Ridge extensions which will override
1448          * some of these numbers in the inode structure.
1449          */
1450 
1451         if (!high_sierra) {
1452                 parse_rock_ridge_inode(de, inode, relocated);
1453                 /* if we want uid/gid set, override the rock ridge setting */
1454                 if (sbi->s_uid_set)
1455                         inode->i_uid = sbi->s_uid;
1456                 if (sbi->s_gid_set)
1457                         inode->i_gid = sbi->s_gid;
1458         }
1459         /* Now set final access rights if overriding rock ridge setting */
1460         if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
1461             sbi->s_dmode != ISOFS_INVALID_MODE)
1462                 inode->i_mode = S_IFDIR | sbi->s_dmode;
1463         if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
1464             sbi->s_fmode != ISOFS_INVALID_MODE)
1465                 inode->i_mode = S_IFREG | sbi->s_fmode;
1466 
1467         /* Install the inode operations vector */
1468         if (S_ISREG(inode->i_mode)) {
1469                 inode->i_fop = &generic_ro_fops;
1470                 switch (ei->i_file_format) {
1471 #ifdef CONFIG_ZISOFS
1472                 case isofs_file_compressed:
1473                         inode->i_data.a_ops = &zisofs_aops;
1474                         break;
1475 #endif
1476                 default:
1477                         inode->i_data.a_ops = &isofs_aops;
1478                         break;
1479                 }
1480         } else if (S_ISDIR(inode->i_mode)) {
1481                 inode->i_op = &isofs_dir_inode_operations;
1482                 inode->i_fop = &isofs_dir_operations;
1483         } else if (S_ISLNK(inode->i_mode)) {
1484                 inode->i_op = &page_symlink_inode_operations;
1485                 inode_nohighmem(inode);
1486                 inode->i_data.a_ops = &isofs_symlink_aops;
1487         } else
1488                 /* XXX - parse_rock_ridge_inode() had already set i_rdev. */
1489                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
1490 
1491         ret = 0;
1492 out:
1493         kfree(tmpde);
1494         if (bh)
1495                 brelse(bh);
1496         return ret;
1497 
1498 out_badread:
1499         printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
1500 fail:
1501         goto out;
1502 }
1503 
1504 struct isofs_iget5_callback_data {
1505         unsigned long block;
1506         unsigned long offset;
1507 };
1508 
1509 static int isofs_iget5_test(struct inode *ino, void *data)
1510 {
1511         struct iso_inode_info *i = ISOFS_I(ino);
1512         struct isofs_iget5_callback_data *d =
1513                 (struct isofs_iget5_callback_data*)data;
1514         return (i->i_iget5_block == d->block)
1515                 && (i->i_iget5_offset == d->offset);
1516 }
1517 
1518 static int isofs_iget5_set(struct inode *ino, void *data)
1519 {
1520         struct iso_inode_info *i = ISOFS_I(ino);
1521         struct isofs_iget5_callback_data *d =
1522                 (struct isofs_iget5_callback_data*)data;
1523         i->i_iget5_block = d->block;
1524         i->i_iget5_offset = d->offset;
1525         return 0;
1526 }
1527 
1528 /* Store, in the inode's containing structure, the block and block
1529  * offset that point to the underlying meta-data for the inode.  The
1530  * code below is otherwise similar to the iget() code in
1531  * include/linux/fs.h */
1532 struct inode *__isofs_iget(struct super_block *sb,
1533                            unsigned long block,
1534                            unsigned long offset,
1535                            int relocated)
1536 {
1537         unsigned long hashval;
1538         struct inode *inode;
1539         struct isofs_iget5_callback_data data;
1540         long ret;
1541 
1542         if (offset >= 1ul << sb->s_blocksize_bits)
1543                 return ERR_PTR(-EINVAL);
1544 
1545         data.block = block;
1546         data.offset = offset;
1547 
1548         hashval = (block << sb->s_blocksize_bits) | offset;
1549 
1550         inode = iget5_locked(sb, hashval, &isofs_iget5_test,
1551                                 &isofs_iget5_set, &data);
1552 
1553         if (!inode)
1554                 return ERR_PTR(-ENOMEM);
1555 
1556         if (inode->i_state & I_NEW) {
1557                 ret = isofs_read_inode(inode, relocated);
1558                 if (ret < 0) {
1559                         iget_failed(inode);
1560                         inode = ERR_PTR(ret);
1561                 } else {
1562                         unlock_new_inode(inode);
1563                 }
1564         }
1565 
1566         return inode;
1567 }
1568 
1569 static struct dentry *isofs_mount(struct file_system_type *fs_type,
1570         int flags, const char *dev_name, void *data)
1571 {
1572         return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
1573 }
1574 
1575 static struct file_system_type iso9660_fs_type = {
1576         .owner          = THIS_MODULE,
1577         .name           = "iso9660",
1578         .mount          = isofs_mount,
1579         .kill_sb        = kill_block_super,
1580         .fs_flags       = FS_REQUIRES_DEV,
1581 };
1582 MODULE_ALIAS_FS("iso9660");
1583 MODULE_ALIAS("iso9660");
1584 
1585 static int __init init_iso9660_fs(void)
1586 {
1587         int err = init_inodecache();
1588         if (err)
1589                 goto out;
1590 #ifdef CONFIG_ZISOFS
1591         err = zisofs_init();
1592         if (err)
1593                 goto out1;
1594 #endif
1595         err = register_filesystem(&iso9660_fs_type);
1596         if (err)
1597                 goto out2;
1598         return 0;
1599 out2:
1600 #ifdef CONFIG_ZISOFS
1601         zisofs_cleanup();
1602 out1:
1603 #endif
1604         destroy_inodecache();
1605 out:
1606         return err;
1607 }
1608 
1609 static void __exit exit_iso9660_fs(void)
1610 {
1611         unregister_filesystem(&iso9660_fs_type);
1612 #ifdef CONFIG_ZISOFS
1613         zisofs_cleanup();
1614 #endif
1615         destroy_inodecache();
1616 }
1617 
1618 module_init(init_iso9660_fs)
1619 module_exit(exit_iso9660_fs)
1620 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/fs/isofs/inode.c

DEFINITIONS
