linux/fs/befs/linuxvfs.c
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   1/*
   2 * linux/fs/befs/linuxvfs.c
   3 *
   4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
   5 *
   6 */
   7
   8#include <linux/module.h>
   9#include <linux/slab.h>
  10#include <linux/fs.h>
  11#include <linux/errno.h>
  12#include <linux/stat.h>
  13#include <linux/nls.h>
  14#include <linux/buffer_head.h>
  15#include <linux/vfs.h>
  16#include <linux/parser.h>
  17#include <linux/namei.h>
  18
  19#include "befs.h"
  20#include "btree.h"
  21#include "inode.h"
  22#include "datastream.h"
  23#include "super.h"
  24#include "io.h"
  25
  26MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
  27MODULE_AUTHOR("Will Dyson");
  28MODULE_LICENSE("GPL");
  29
  30/* The units the vfs expects inode->i_blocks to be in */
  31#define VFS_BLOCK_SIZE 512
  32
  33static int befs_readdir(struct file *, void *, filldir_t);
  34static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
  35static int befs_readpage(struct file *file, struct page *page);
  36static sector_t befs_bmap(struct address_space *mapping, sector_t block);
  37static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int);
  38static struct inode *befs_iget(struct super_block *, unsigned long);
  39static struct inode *befs_alloc_inode(struct super_block *sb);
  40static void befs_destroy_inode(struct inode *inode);
  41static int befs_init_inodecache(void);
  42static void befs_destroy_inodecache(void);
  43static void *befs_follow_link(struct dentry *, struct nameidata *);
  44static void befs_put_link(struct dentry *, struct nameidata *, void *);
  45static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
  46                        char **out, int *out_len);
  47static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
  48                        char **out, int *out_len);
  49static void befs_put_super(struct super_block *);
  50static int befs_remount(struct super_block *, int *, char *);
  51static int befs_statfs(struct dentry *, struct kstatfs *);
  52static int parse_options(char *, befs_mount_options *);
  53
  54static const struct super_operations befs_sops = {
  55        .alloc_inode    = befs_alloc_inode,     /* allocate a new inode */
  56        .destroy_inode  = befs_destroy_inode, /* deallocate an inode */
  57        .put_super      = befs_put_super,       /* uninit super */
  58        .statfs         = befs_statfs,  /* statfs */
  59        .remount_fs     = befs_remount,
  60        .show_options   = generic_show_options,
  61};
  62
  63/* slab cache for befs_inode_info objects */
  64static struct kmem_cache *befs_inode_cachep;
  65
  66static const struct file_operations befs_dir_operations = {
  67        .read           = generic_read_dir,
  68        .readdir        = befs_readdir,
  69        .llseek         = generic_file_llseek,
  70};
  71
  72static const struct inode_operations befs_dir_inode_operations = {
  73        .lookup         = befs_lookup,
  74};
  75
  76static const struct address_space_operations befs_aops = {
  77        .readpage       = befs_readpage,
  78        .bmap           = befs_bmap,
  79};
  80
  81static const struct inode_operations befs_symlink_inode_operations = {
  82        .readlink       = generic_readlink,
  83        .follow_link    = befs_follow_link,
  84        .put_link       = befs_put_link,
  85};
  86
  87/* 
  88 * Called by generic_file_read() to read a page of data
  89 * 
  90 * In turn, simply calls a generic block read function and
  91 * passes it the address of befs_get_block, for mapping file
  92 * positions to disk blocks.
  93 */
  94static int
  95befs_readpage(struct file *file, struct page *page)
  96{
  97        return block_read_full_page(page, befs_get_block);
  98}
  99
 100static sector_t
 101befs_bmap(struct address_space *mapping, sector_t block)
 102{
 103        return generic_block_bmap(mapping, block, befs_get_block);
 104}
 105
 106/* 
 107 * Generic function to map a file position (block) to a 
 108 * disk offset (passed back in bh_result).
 109 *
 110 * Used by many higher level functions.
 111 *
 112 * Calls befs_fblock2brun() in datastream.c to do the real work.
 113 *
 114 * -WD 10-26-01
 115 */
 116
 117static int
 118befs_get_block(struct inode *inode, sector_t block,
 119               struct buffer_head *bh_result, int create)
 120{
 121        struct super_block *sb = inode->i_sb;
 122        befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
 123        befs_block_run run = BAD_IADDR;
 124        int res = 0;
 125        ulong disk_off;
 126
 127        befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
 128                   inode->i_ino, block);
 129
 130        if (block < 0) {
 131                befs_error(sb, "befs_get_block() was asked for a block "
 132                           "number less than zero: block %ld in inode %lu",
 133                           block, inode->i_ino);
 134                return -EIO;
 135        }
 136
 137        if (create) {
 138                befs_error(sb, "befs_get_block() was asked to write to "
 139                           "block %ld in inode %lu", block, inode->i_ino);
 140                return -EPERM;
 141        }
 142
 143        res = befs_fblock2brun(sb, ds, block, &run);
 144        if (res != BEFS_OK) {
 145                befs_error(sb,
 146                           "<--- befs_get_block() for inode %lu, block "
 147                           "%ld ERROR", inode->i_ino, block);
 148                return -EFBIG;
 149        }
 150
 151        disk_off = (ulong) iaddr2blockno(sb, &run);
 152
 153        map_bh(bh_result, inode->i_sb, disk_off);
 154
 155        befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
 156                   "disk address %lu", inode->i_ino, block, disk_off);
 157
 158        return 0;
 159}
 160
 161static struct dentry *
 162befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 163{
 164        struct inode *inode = NULL;
 165        struct super_block *sb = dir->i_sb;
 166        befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
 167        befs_off_t offset;
 168        int ret;
 169        int utfnamelen;
 170        char *utfname;
 171        const char *name = dentry->d_name.name;
 172
 173        befs_debug(sb, "---> befs_lookup() "
 174                   "name %s inode %ld", dentry->d_name.name, dir->i_ino);
 175
 176        /* Convert to UTF-8 */
 177        if (BEFS_SB(sb)->nls) {
 178                ret =
 179                    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
 180                if (ret < 0) {
 181                        befs_debug(sb, "<--- befs_lookup() ERROR");
 182                        return ERR_PTR(ret);
 183                }
 184                ret = befs_btree_find(sb, ds, utfname, &offset);
 185                kfree(utfname);
 186
 187        } else {
 188                ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
 189        }
 190
 191        if (ret == BEFS_BT_NOT_FOUND) {
 192                befs_debug(sb, "<--- befs_lookup() %s not found",
 193                           dentry->d_name.name);
 194                return ERR_PTR(-ENOENT);
 195
 196        } else if (ret != BEFS_OK || offset == 0) {
 197                befs_warning(sb, "<--- befs_lookup() Error");
 198                return ERR_PTR(-ENODATA);
 199        }
 200
 201        inode = befs_iget(dir->i_sb, (ino_t) offset);
 202        if (IS_ERR(inode))
 203                return ERR_CAST(inode);
 204
 205        d_add(dentry, inode);
 206
 207        befs_debug(sb, "<--- befs_lookup()");
 208
 209        return NULL;
 210}
 211
 212static int
 213befs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 214{
 215        struct inode *inode = filp->f_path.dentry->d_inode;
 216        struct super_block *sb = inode->i_sb;
 217        befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
 218        befs_off_t value;
 219        int result;
 220        size_t keysize;
 221        unsigned char d_type;
 222        char keybuf[BEFS_NAME_LEN + 1];
 223        char *nlsname;
 224        int nlsnamelen;
 225        const char *dirname = filp->f_path.dentry->d_name.name;
 226
 227        befs_debug(sb, "---> befs_readdir() "
 228                   "name %s, inode %ld, filp->f_pos %Ld",
 229                   dirname, inode->i_ino, filp->f_pos);
 230
 231        result = befs_btree_read(sb, ds, filp->f_pos, BEFS_NAME_LEN + 1,
 232                                 keybuf, &keysize, &value);
 233
 234        if (result == BEFS_ERR) {
 235                befs_debug(sb, "<--- befs_readdir() ERROR");
 236                befs_error(sb, "IO error reading %s (inode %lu)",
 237                           dirname, inode->i_ino);
 238                return -EIO;
 239
 240        } else if (result == BEFS_BT_END) {
 241                befs_debug(sb, "<--- befs_readdir() END");
 242                return 0;
 243
 244        } else if (result == BEFS_BT_EMPTY) {
 245                befs_debug(sb, "<--- befs_readdir() Empty directory");
 246                return 0;
 247        }
 248
 249        d_type = DT_UNKNOWN;
 250
 251        /* Convert to NLS */
 252        if (BEFS_SB(sb)->nls) {
 253                result =
 254                    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
 255                if (result < 0) {
 256                        befs_debug(sb, "<--- befs_readdir() ERROR");
 257                        return result;
 258                }
 259                result = filldir(dirent, nlsname, nlsnamelen, filp->f_pos,
 260                                 (ino_t) value, d_type);
 261                kfree(nlsname);
 262
 263        } else {
 264                result = filldir(dirent, keybuf, keysize, filp->f_pos,
 265                                 (ino_t) value, d_type);
 266        }
 267
 268        filp->f_pos++;
 269
 270        befs_debug(sb, "<--- befs_readdir() filp->f_pos %Ld", filp->f_pos);
 271
 272        return 0;
 273}
 274
 275static struct inode *
 276befs_alloc_inode(struct super_block *sb)
 277{
 278        struct befs_inode_info *bi;
 279        bi = (struct befs_inode_info *)kmem_cache_alloc(befs_inode_cachep,
 280                                                        GFP_KERNEL);
 281        if (!bi)
 282                return NULL;
 283        return &bi->vfs_inode;
 284}
 285
 286static void befs_i_callback(struct rcu_head *head)
 287{
 288        struct inode *inode = container_of(head, struct inode, i_rcu);
 289        kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
 290}
 291
 292static void befs_destroy_inode(struct inode *inode)
 293{
 294        call_rcu(&inode->i_rcu, befs_i_callback);
 295}
 296
 297static void init_once(void *foo)
 298{
 299        struct befs_inode_info *bi = (struct befs_inode_info *) foo;
 300
 301        inode_init_once(&bi->vfs_inode);
 302}
 303
 304static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
 305{
 306        struct buffer_head *bh = NULL;
 307        befs_inode *raw_inode = NULL;
 308
 309        befs_sb_info *befs_sb = BEFS_SB(sb);
 310        befs_inode_info *befs_ino = NULL;
 311        struct inode *inode;
 312        long ret = -EIO;
 313
 314        befs_debug(sb, "---> befs_read_inode() " "inode = %lu", ino);
 315
 316        inode = iget_locked(sb, ino);
 317        if (IS_ERR(inode))
 318                return inode;
 319        if (!(inode->i_state & I_NEW))
 320                return inode;
 321
 322        befs_ino = BEFS_I(inode);
 323
 324        /* convert from vfs's inode number to befs's inode number */
 325        befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
 326
 327        befs_debug(sb, "  real inode number [%u, %hu, %hu]",
 328                   befs_ino->i_inode_num.allocation_group,
 329                   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
 330
 331        bh = befs_bread(sb, inode->i_ino);
 332        if (!bh) {
 333                befs_error(sb, "unable to read inode block - "
 334                           "inode = %lu", inode->i_ino);
 335                goto unacquire_none;
 336        }
 337
 338        raw_inode = (befs_inode *) bh->b_data;
 339
 340        befs_dump_inode(sb, raw_inode);
 341
 342        if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
 343                befs_error(sb, "Bad inode: %lu", inode->i_ino);
 344                goto unacquire_bh;
 345        }
 346
 347        inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
 348
 349        /*
 350         * set uid and gid.  But since current BeOS is single user OS, so
 351         * you can change by "uid" or "gid" options.
 352         */   
 353
 354        inode->i_uid = befs_sb->mount_opts.use_uid ?
 355            befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
 356        inode->i_gid = befs_sb->mount_opts.use_gid ?
 357            befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
 358
 359        set_nlink(inode, 1);
 360
 361        /*
 362         * BEFS's time is 64 bits, but current VFS is 32 bits...
 363         * BEFS don't have access time. Nor inode change time. VFS
 364         * doesn't have creation time.
 365         * Also, the lower 16 bits of the last_modified_time and 
 366         * create_time are just a counter to help ensure uniqueness
 367         * for indexing purposes. (PFD, page 54)
 368         */
 369
 370        inode->i_mtime.tv_sec =
 371            fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
 372        inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */        
 373        inode->i_ctime = inode->i_mtime;
 374        inode->i_atime = inode->i_mtime;
 375
 376        befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
 377        befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
 378        befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
 379        befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
 380
 381        if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
 382                inode->i_size = 0;
 383                inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
 384                strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
 385                        BEFS_SYMLINK_LEN - 1);
 386                befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
 387        } else {
 388                int num_blks;
 389
 390                befs_ino->i_data.ds =
 391                    fsds_to_cpu(sb, &raw_inode->data.datastream);
 392
 393                num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
 394                inode->i_blocks =
 395                    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
 396                inode->i_size = befs_ino->i_data.ds.size;
 397        }
 398
 399        inode->i_mapping->a_ops = &befs_aops;
 400
 401        if (S_ISREG(inode->i_mode)) {
 402                inode->i_fop = &generic_ro_fops;
 403        } else if (S_ISDIR(inode->i_mode)) {
 404                inode->i_op = &befs_dir_inode_operations;
 405                inode->i_fop = &befs_dir_operations;
 406        } else if (S_ISLNK(inode->i_mode)) {
 407                inode->i_op = &befs_symlink_inode_operations;
 408        } else {
 409                befs_error(sb, "Inode %lu is not a regular file, "
 410                           "directory or symlink. THAT IS WRONG! BeFS has no "
 411                           "on disk special files", inode->i_ino);
 412                goto unacquire_bh;
 413        }
 414
 415        brelse(bh);
 416        befs_debug(sb, "<--- befs_read_inode()");
 417        unlock_new_inode(inode);
 418        return inode;
 419
 420      unacquire_bh:
 421        brelse(bh);
 422
 423      unacquire_none:
 424        iget_failed(inode);
 425        befs_debug(sb, "<--- befs_read_inode() - Bad inode");
 426        return ERR_PTR(ret);
 427}
 428
 429/* Initialize the inode cache. Called at fs setup.
 430 *
 431 * Taken from NFS implementation by Al Viro.
 432 */
 433static int
 434befs_init_inodecache(void)
 435{
 436        befs_inode_cachep = kmem_cache_create("befs_inode_cache",
 437                                              sizeof (struct befs_inode_info),
 438                                              0, (SLAB_RECLAIM_ACCOUNT|
 439                                                SLAB_MEM_SPREAD),
 440                                              init_once);
 441        if (befs_inode_cachep == NULL) {
 442                printk(KERN_ERR "befs_init_inodecache: "
 443                       "Couldn't initialize inode slabcache\n");
 444                return -ENOMEM;
 445        }
 446
 447        return 0;
 448}
 449
 450/* Called at fs teardown.
 451 * 
 452 * Taken from NFS implementation by Al Viro.
 453 */
 454static void
 455befs_destroy_inodecache(void)
 456{
 457        kmem_cache_destroy(befs_inode_cachep);
 458}
 459
 460/*
 461 * The inode of symbolic link is different to data stream.
 462 * The data stream become link name. Unless the LONG_SYMLINK
 463 * flag is set.
 464 */
 465static void *
 466befs_follow_link(struct dentry *dentry, struct nameidata *nd)
 467{
 468        befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
 469        char *link;
 470
 471        if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
 472                struct super_block *sb = dentry->d_sb;
 473                befs_data_stream *data = &befs_ino->i_data.ds;
 474                befs_off_t len = data->size;
 475
 476                if (len == 0) {
 477                        befs_error(sb, "Long symlink with illegal length");
 478                        link = ERR_PTR(-EIO);
 479                } else {
 480                        befs_debug(sb, "Follow long symlink");
 481
 482                        link = kmalloc(len, GFP_NOFS);
 483                        if (!link) {
 484                                link = ERR_PTR(-ENOMEM);
 485                        } else if (befs_read_lsymlink(sb, data, link, len) != len) {
 486                                kfree(link);
 487                                befs_error(sb, "Failed to read entire long symlink");
 488                                link = ERR_PTR(-EIO);
 489                        } else {
 490                                link[len - 1] = '\0';
 491                        }
 492                }
 493        } else {
 494                link = befs_ino->i_data.symlink;
 495        }
 496
 497        nd_set_link(nd, link);
 498        return NULL;
 499}
 500
 501static void befs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
 502{
 503        befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
 504        if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
 505                char *link = nd_get_link(nd);
 506                if (!IS_ERR(link))
 507                        kfree(link);
 508        }
 509}
 510
 511/*
 512 * UTF-8 to NLS charset  convert routine
 513 * 
 514 *
 515 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
 516 * the nls tables directly
 517 */
 518
 519static int
 520befs_utf2nls(struct super_block *sb, const char *in,
 521             int in_len, char **out, int *out_len)
 522{
 523        struct nls_table *nls = BEFS_SB(sb)->nls;
 524        int i, o;
 525        unicode_t uni;
 526        int unilen, utflen;
 527        char *result;
 528        /* The utf8->nls conversion won't make the final nls string bigger
 529         * than the utf one, but if the string is pure ascii they'll have the
 530         * same width and an extra char is needed to save the additional \0
 531         */
 532        int maxlen = in_len + 1;
 533
 534        befs_debug(sb, "---> utf2nls()");
 535
 536        if (!nls) {
 537                befs_error(sb, "befs_utf2nls called with no NLS table loaded");
 538                return -EINVAL;
 539        }
 540
 541        *out = result = kmalloc(maxlen, GFP_NOFS);
 542        if (!*out) {
 543                befs_error(sb, "befs_utf2nls() cannot allocate memory");
 544                *out_len = 0;
 545                return -ENOMEM;
 546        }
 547
 548        for (i = o = 0; i < in_len; i += utflen, o += unilen) {
 549
 550                /* convert from UTF-8 to Unicode */
 551                utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
 552                if (utflen < 0)
 553                        goto conv_err;
 554
 555                /* convert from Unicode to nls */
 556                if (uni > MAX_WCHAR_T)
 557                        goto conv_err;
 558                unilen = nls->uni2char(uni, &result[o], in_len - o);
 559                if (unilen < 0)
 560                        goto conv_err;
 561        }
 562        result[o] = '\0';
 563        *out_len = o;
 564
 565        befs_debug(sb, "<--- utf2nls()");
 566
 567        return o;
 568
 569      conv_err:
 570        befs_error(sb, "Name using character set %s contains a character that "
 571                   "cannot be converted to unicode.", nls->charset);
 572        befs_debug(sb, "<--- utf2nls()");
 573        kfree(result);
 574        return -EILSEQ;
 575}
 576
 577/**
 578 * befs_nls2utf - Convert NLS string to utf8 encodeing
 579 * @sb: Superblock
 580 * @src: Input string buffer in NLS format
 581 * @srclen: Length of input string in bytes
 582 * @dest: The output string in UTF-8 format
 583 * @destlen: Length of the output buffer
 584 * 
 585 * Converts input string @src, which is in the format of the loaded NLS map,
 586 * into a utf8 string.
 587 * 
 588 * The destination string @dest is allocated by this function and the caller is
 589 * responsible for freeing it with kfree()
 590 * 
 591 * On return, *@destlen is the length of @dest in bytes.
 592 *
 593 * On success, the return value is the number of utf8 characters written to
 594 * the output buffer @dest.
 595 *  
 596 * On Failure, a negative number coresponding to the error code is returned.
 597 */
 598
 599static int
 600befs_nls2utf(struct super_block *sb, const char *in,
 601             int in_len, char **out, int *out_len)
 602{
 603        struct nls_table *nls = BEFS_SB(sb)->nls;
 604        int i, o;
 605        wchar_t uni;
 606        int unilen, utflen;
 607        char *result;
 608        /* There're nls characters that will translate to 3-chars-wide UTF-8
 609         * characters, a additional byte is needed to save the final \0
 610         * in special cases */
 611        int maxlen = (3 * in_len) + 1;
 612
 613        befs_debug(sb, "---> nls2utf()\n");
 614
 615        if (!nls) {
 616                befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
 617                return -EINVAL;
 618        }
 619
 620        *out = result = kmalloc(maxlen, GFP_NOFS);
 621        if (!*out) {
 622                befs_error(sb, "befs_nls2utf() cannot allocate memory");
 623                *out_len = 0;
 624                return -ENOMEM;
 625        }
 626
 627        for (i = o = 0; i < in_len; i += unilen, o += utflen) {
 628
 629                /* convert from nls to unicode */
 630                unilen = nls->char2uni(&in[i], in_len - i, &uni);
 631                if (unilen < 0)
 632                        goto conv_err;
 633
 634                /* convert from unicode to UTF-8 */
 635                utflen = utf32_to_utf8(uni, &result[o], 3);
 636                if (utflen <= 0)
 637                        goto conv_err;
 638        }
 639
 640        result[o] = '\0';
 641        *out_len = o;
 642
 643        befs_debug(sb, "<--- nls2utf()");
 644
 645        return i;
 646
 647      conv_err:
 648        befs_error(sb, "Name using charecter set %s contains a charecter that "
 649                   "cannot be converted to unicode.", nls->charset);
 650        befs_debug(sb, "<--- nls2utf()");
 651        kfree(result);
 652        return -EILSEQ;
 653}
 654
 655/**
 656 * Use the
 657 *
 658 */
 659enum {
 660        Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
 661};
 662
 663static const match_table_t befs_tokens = {
 664        {Opt_uid, "uid=%d"},
 665        {Opt_gid, "gid=%d"},
 666        {Opt_charset, "iocharset=%s"},
 667        {Opt_debug, "debug"},
 668        {Opt_err, NULL}
 669};
 670
 671static int
 672parse_options(char *options, befs_mount_options * opts)
 673{
 674        char *p;
 675        substring_t args[MAX_OPT_ARGS];
 676        int option;
 677
 678        /* Initialize options */
 679        opts->uid = 0;
 680        opts->gid = 0;
 681        opts->use_uid = 0;
 682        opts->use_gid = 0;
 683        opts->iocharset = NULL;
 684        opts->debug = 0;
 685
 686        if (!options)
 687                return 1;
 688
 689        while ((p = strsep(&options, ",")) != NULL) {
 690                int token;
 691                if (!*p)
 692                        continue;
 693
 694                token = match_token(p, befs_tokens, args);
 695                switch (token) {
 696                case Opt_uid:
 697                        if (match_int(&args[0], &option))
 698                                return 0;
 699                        if (option < 0) {
 700                                printk(KERN_ERR "BeFS: Invalid uid %d, "
 701                                                "using default\n", option);
 702                                break;
 703                        }
 704                        opts->uid = option;
 705                        opts->use_uid = 1;
 706                        break;
 707                case Opt_gid:
 708                        if (match_int(&args[0], &option))
 709                                return 0;
 710                        if (option < 0) {
 711                                printk(KERN_ERR "BeFS: Invalid gid %d, "
 712                                                "using default\n", option);
 713                                break;
 714                        }
 715                        opts->gid = option;
 716                        opts->use_gid = 1;
 717                        break;
 718                case Opt_charset:
 719                        kfree(opts->iocharset);
 720                        opts->iocharset = match_strdup(&args[0]);
 721                        if (!opts->iocharset) {
 722                                printk(KERN_ERR "BeFS: allocation failure for "
 723                                                "iocharset string\n");
 724                                return 0;
 725                        }
 726                        break;
 727                case Opt_debug:
 728                        opts->debug = 1;
 729                        break;
 730                default:
 731                        printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
 732                                        "or missing value\n", p);
 733                        return 0;
 734                }
 735        }
 736        return 1;
 737}
 738
 739/* This function has the responsibiltiy of getting the
 740 * filesystem ready for unmounting. 
 741 * Basically, we free everything that we allocated in
 742 * befs_read_inode
 743 */
 744static void
 745befs_put_super(struct super_block *sb)
 746{
 747        kfree(BEFS_SB(sb)->mount_opts.iocharset);
 748        BEFS_SB(sb)->mount_opts.iocharset = NULL;
 749        unload_nls(BEFS_SB(sb)->nls);
 750        kfree(sb->s_fs_info);
 751        sb->s_fs_info = NULL;
 752}
 753
 754/* Allocate private field of the superblock, fill it.
 755 *
 756 * Finish filling the public superblock fields
 757 * Make the root directory
 758 * Load a set of NLS translations if needed.
 759 */
 760static int
 761befs_fill_super(struct super_block *sb, void *data, int silent)
 762{
 763        struct buffer_head *bh;
 764        befs_sb_info *befs_sb;
 765        befs_super_block *disk_sb;
 766        struct inode *root;
 767        long ret = -EINVAL;
 768        const unsigned long sb_block = 0;
 769        const off_t x86_sb_off = 512;
 770
 771        save_mount_options(sb, data);
 772
 773        sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
 774        if (sb->s_fs_info == NULL) {
 775                printk(KERN_ERR
 776                       "BeFS(%s): Unable to allocate memory for private "
 777                       "portion of superblock. Bailing.\n", sb->s_id);
 778                goto unacquire_none;
 779        }
 780        befs_sb = BEFS_SB(sb);
 781        memset(befs_sb, 0, sizeof(befs_sb_info));
 782
 783        if (!parse_options((char *) data, &befs_sb->mount_opts)) {
 784                befs_error(sb, "cannot parse mount options");
 785                goto unacquire_priv_sbp;
 786        }
 787
 788        befs_debug(sb, "---> befs_fill_super()");
 789
 790#ifndef CONFIG_BEFS_RW
 791        if (!(sb->s_flags & MS_RDONLY)) {
 792                befs_warning(sb,
 793                             "No write support. Marking filesystem read-only");
 794                sb->s_flags |= MS_RDONLY;
 795        }
 796#endif                          /* CONFIG_BEFS_RW */
 797
 798        /*
 799         * Set dummy blocksize to read super block.
 800         * Will be set to real fs blocksize later.
 801         *
 802         * Linux 2.4.10 and later refuse to read blocks smaller than
 803         * the hardsect size for the device. But we also need to read at 
 804         * least 1k to get the second 512 bytes of the volume.
 805         * -WD 10-26-01
 806         */ 
 807        sb_min_blocksize(sb, 1024);
 808
 809        if (!(bh = sb_bread(sb, sb_block))) {
 810                befs_error(sb, "unable to read superblock");
 811                goto unacquire_priv_sbp;
 812        }
 813
 814        /* account for offset of super block on x86 */
 815        disk_sb = (befs_super_block *) bh->b_data;
 816        if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
 817            (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
 818                befs_debug(sb, "Using PPC superblock location");
 819        } else {
 820                befs_debug(sb, "Using x86 superblock location");
 821                disk_sb =
 822                    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
 823        }
 824
 825        if (befs_load_sb(sb, disk_sb) != BEFS_OK)
 826                goto unacquire_bh;
 827
 828        befs_dump_super_block(sb, disk_sb);
 829
 830        brelse(bh);
 831
 832        if (befs_check_sb(sb) != BEFS_OK)
 833                goto unacquire_priv_sbp;
 834
 835        if( befs_sb->num_blocks > ~((sector_t)0) ) {
 836                befs_error(sb, "blocks count: %Lu "
 837                        "is larger than the host can use",
 838                        befs_sb->num_blocks);
 839                goto unacquire_priv_sbp;
 840        }
 841
 842        /*
 843         * set up enough so that it can read an inode
 844         * Fill in kernel superblock fields from private sb
 845         */
 846        sb->s_magic = BEFS_SUPER_MAGIC;
 847        /* Set real blocksize of fs */
 848        sb_set_blocksize(sb, (ulong) befs_sb->block_size);
 849        sb->s_op = &befs_sops;
 850        root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
 851        if (IS_ERR(root)) {
 852                ret = PTR_ERR(root);
 853                goto unacquire_priv_sbp;
 854        }
 855        sb->s_root = d_make_root(root);
 856        if (!sb->s_root) {
 857                befs_error(sb, "get root inode failed");
 858                goto unacquire_priv_sbp;
 859        }
 860
 861        /* load nls library */
 862        if (befs_sb->mount_opts.iocharset) {
 863                befs_debug(sb, "Loading nls: %s",
 864                           befs_sb->mount_opts.iocharset);
 865                befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
 866                if (!befs_sb->nls) {
 867                        befs_warning(sb, "Cannot load nls %s"
 868                                        " loading default nls",
 869                                        befs_sb->mount_opts.iocharset);
 870                        befs_sb->nls = load_nls_default();
 871                }
 872        /* load default nls if none is specified  in mount options */
 873        } else {
 874                befs_debug(sb, "Loading default nls");
 875                befs_sb->nls = load_nls_default();
 876        }
 877
 878        return 0;
 879/*****************/
 880      unacquire_bh:
 881        brelse(bh);
 882
 883      unacquire_priv_sbp:
 884        kfree(befs_sb->mount_opts.iocharset);
 885        kfree(sb->s_fs_info);
 886
 887      unacquire_none:
 888        sb->s_fs_info = NULL;
 889        return ret;
 890}
 891
 892static int
 893befs_remount(struct super_block *sb, int *flags, char *data)
 894{
 895        if (!(*flags & MS_RDONLY))
 896                return -EINVAL;
 897        return 0;
 898}
 899
 900static int
 901befs_statfs(struct dentry *dentry, struct kstatfs *buf)
 902{
 903        struct super_block *sb = dentry->d_sb;
 904        u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 905
 906        befs_debug(sb, "---> befs_statfs()");
 907
 908        buf->f_type = BEFS_SUPER_MAGIC;
 909        buf->f_bsize = sb->s_blocksize;
 910        buf->f_blocks = BEFS_SB(sb)->num_blocks;
 911        buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
 912        buf->f_bavail = buf->f_bfree;
 913        buf->f_files = 0;       /* UNKNOWN */
 914        buf->f_ffree = 0;       /* UNKNOWN */
 915        buf->f_fsid.val[0] = (u32)id;
 916        buf->f_fsid.val[1] = (u32)(id >> 32);
 917        buf->f_namelen = BEFS_NAME_LEN;
 918
 919        befs_debug(sb, "<--- befs_statfs()");
 920
 921        return 0;
 922}
 923
 924static struct dentry *
 925befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
 926            void *data)
 927{
 928        return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
 929}
 930
 931static struct file_system_type befs_fs_type = {
 932        .owner          = THIS_MODULE,
 933        .name           = "befs",
 934        .mount          = befs_mount,
 935        .kill_sb        = kill_block_super,
 936        .fs_flags       = FS_REQUIRES_DEV,      
 937};
 938
 939static int __init
 940init_befs_fs(void)
 941{
 942        int err;
 943
 944        printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
 945
 946        err = befs_init_inodecache();
 947        if (err)
 948                goto unacquire_none;
 949
 950        err = register_filesystem(&befs_fs_type);
 951        if (err)
 952                goto unacquire_inodecache;
 953
 954        return 0;
 955
 956unacquire_inodecache:
 957        befs_destroy_inodecache();
 958
 959unacquire_none:
 960        return err;
 961}
 962
 963static void __exit
 964exit_befs_fs(void)
 965{
 966        befs_destroy_inodecache();
 967
 968        unregister_filesystem(&befs_fs_type);
 969}
 970
 971/*
 972Macros that typecheck the init and exit functions,
 973ensures that they are called at init and cleanup,
 974and eliminates warnings about unused functions.
 975*/
 976module_init(init_befs_fs)
 977module_exit(exit_befs_fs)
 978
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