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#include <linux/sched.h>
  19
  20#include "befs.h"
  21#include "btree.h"
  22#include "inode.h"
  23#include "datastream.h"
  24#include "super.h"
  25#include "io.h"
  26
  27MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
  28MODULE_AUTHOR("Will Dyson");
  29MODULE_LICENSE("GPL");
  30
  31/* The units the vfs expects inode->i_blocks to be in */
  32#define VFS_BLOCK_SIZE 512
  33
  34static int befs_readdir(struct file *, struct dir_context *);
  35static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
  36static int befs_readpage(struct file *file, struct page *page);
  37static sector_t befs_bmap(struct address_space *mapping, sector_t block);
  38static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int);
  39static struct inode *befs_iget(struct super_block *, unsigned long);
  40static struct inode *befs_alloc_inode(struct super_block *sb);
  41static void befs_destroy_inode(struct inode *inode);
  42static int befs_init_inodecache(void);
  43static void befs_destroy_inodecache(void);
  44static void *befs_follow_link(struct dentry *, struct nameidata *);
  45static void *befs_fast_follow_link(struct dentry *, struct nameidata *);
  46static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
  47                        char **out, int *out_len);
  48static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
  49                        char **out, int *out_len);
  50static void befs_put_super(struct super_block *);
  51static int befs_remount(struct super_block *, int *, char *);
  52static int befs_statfs(struct dentry *, struct kstatfs *);
  53static int parse_options(char *, befs_mount_options *);
  54
  55static const struct super_operations befs_sops = {
  56        .alloc_inode    = befs_alloc_inode,     /* allocate a new inode */
  57        .destroy_inode  = befs_destroy_inode, /* deallocate an inode */
  58        .put_super      = befs_put_super,       /* uninit super */
  59        .statfs         = befs_statfs,  /* statfs */
  60        .remount_fs     = befs_remount,
  61        .show_options   = generic_show_options,
  62};
  63
  64/* slab cache for befs_inode_info objects */
  65static struct kmem_cache *befs_inode_cachep;
  66
  67static const struct file_operations befs_dir_operations = {
  68        .read           = generic_read_dir,
  69        .iterate        = befs_readdir,
  70        .llseek         = generic_file_llseek,
  71};
  72
  73static const struct inode_operations befs_dir_inode_operations = {
  74        .lookup         = befs_lookup,
  75};
  76
  77static const struct address_space_operations befs_aops = {
  78        .readpage       = befs_readpage,
  79        .bmap           = befs_bmap,
  80};
  81
  82static const struct inode_operations befs_fast_symlink_inode_operations = {
  83        .readlink       = generic_readlink,
  84        .follow_link    = befs_fast_follow_link,
  85};
  86
  87static const struct inode_operations befs_symlink_inode_operations = {
  88        .readlink       = generic_readlink,
  89        .follow_link    = befs_follow_link,
  90        .put_link       = kfree_put_link,
  91};
  92
  93/* 
  94 * Called by generic_file_read() to read a page of data
  95 * 
  96 * In turn, simply calls a generic block read function and
  97 * passes it the address of befs_get_block, for mapping file
  98 * positions to disk blocks.
  99 */
 100static int
 101befs_readpage(struct file *file, struct page *page)
 102{
 103        return block_read_full_page(page, befs_get_block);
 104}
 105
 106static sector_t
 107befs_bmap(struct address_space *mapping, sector_t block)
 108{
 109        return generic_block_bmap(mapping, block, befs_get_block);
 110}
 111
 112/* 
 113 * Generic function to map a file position (block) to a 
 114 * disk offset (passed back in bh_result).
 115 *
 116 * Used by many higher level functions.
 117 *
 118 * Calls befs_fblock2brun() in datastream.c to do the real work.
 119 *
 120 * -WD 10-26-01
 121 */
 122
 123static int
 124befs_get_block(struct inode *inode, sector_t block,
 125               struct buffer_head *bh_result, int create)
 126{
 127        struct super_block *sb = inode->i_sb;
 128        befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
 129        befs_block_run run = BAD_IADDR;
 130        int res = 0;
 131        ulong disk_off;
 132
 133        befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
 134                   inode->i_ino, block);
 135
 136        if (block < 0) {
 137                befs_error(sb, "befs_get_block() was asked for a block "
 138                           "number less than zero: block %ld in inode %lu",
 139                           block, inode->i_ino);
 140                return -EIO;
 141        }
 142
 143        if (create) {
 144                befs_error(sb, "befs_get_block() was asked to write to "
 145                           "block %ld in inode %lu", block, inode->i_ino);
 146                return -EPERM;
 147        }
 148
 149        res = befs_fblock2brun(sb, ds, block, &run);
 150        if (res != BEFS_OK) {
 151                befs_error(sb,
 152                           "<--- befs_get_block() for inode %lu, block "
 153                           "%ld ERROR", inode->i_ino, block);
 154                return -EFBIG;
 155        }
 156
 157        disk_off = (ulong) iaddr2blockno(sb, &run);
 158
 159        map_bh(bh_result, inode->i_sb, disk_off);
 160
 161        befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
 162                   "disk address %lu", inode->i_ino, block, disk_off);
 163
 164        return 0;
 165}
 166
 167static struct dentry *
 168befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 169{
 170        struct inode *inode = NULL;
 171        struct super_block *sb = dir->i_sb;
 172        befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
 173        befs_off_t offset;
 174        int ret;
 175        int utfnamelen;
 176        char *utfname;
 177        const char *name = dentry->d_name.name;
 178
 179        befs_debug(sb, "---> befs_lookup() "
 180                   "name %s inode %ld", dentry->d_name.name, dir->i_ino);
 181
 182        /* Convert to UTF-8 */
 183        if (BEFS_SB(sb)->nls) {
 184                ret =
 185                    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
 186                if (ret < 0) {
 187                        befs_debug(sb, "<--- befs_lookup() ERROR");
 188                        return ERR_PTR(ret);
 189                }
 190                ret = befs_btree_find(sb, ds, utfname, &offset);
 191                kfree(utfname);
 192
 193        } else {
 194                ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
 195        }
 196
 197        if (ret == BEFS_BT_NOT_FOUND) {
 198                befs_debug(sb, "<--- befs_lookup() %s not found",
 199                           dentry->d_name.name);
 200                return ERR_PTR(-ENOENT);
 201
 202        } else if (ret != BEFS_OK || offset == 0) {
 203                befs_warning(sb, "<--- befs_lookup() Error");
 204                return ERR_PTR(-ENODATA);
 205        }
 206
 207        inode = befs_iget(dir->i_sb, (ino_t) offset);
 208        if (IS_ERR(inode))
 209                return ERR_CAST(inode);
 210
 211        d_add(dentry, inode);
 212
 213        befs_debug(sb, "<--- befs_lookup()");
 214
 215        return NULL;
 216}
 217
 218static int
 219befs_readdir(struct file *file, struct dir_context *ctx)
 220{
 221        struct inode *inode = file_inode(file);
 222        struct super_block *sb = inode->i_sb;
 223        befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
 224        befs_off_t value;
 225        int result;
 226        size_t keysize;
 227        unsigned char d_type;
 228        char keybuf[BEFS_NAME_LEN + 1];
 229        const char *dirname = file->f_path.dentry->d_name.name;
 230
 231        befs_debug(sb, "---> befs_readdir() "
 232                   "name %s, inode %ld, ctx->pos %Ld",
 233                   dirname, inode->i_ino, ctx->pos);
 234
 235more:
 236        result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
 237                                 keybuf, &keysize, &value);
 238
 239        if (result == BEFS_ERR) {
 240                befs_debug(sb, "<--- befs_readdir() ERROR");
 241                befs_error(sb, "IO error reading %s (inode %lu)",
 242                           dirname, inode->i_ino);
 243                return -EIO;
 244
 245        } else if (result == BEFS_BT_END) {
 246                befs_debug(sb, "<--- befs_readdir() END");
 247                return 0;
 248
 249        } else if (result == BEFS_BT_EMPTY) {
 250                befs_debug(sb, "<--- befs_readdir() Empty directory");
 251                return 0;
 252        }
 253
 254        d_type = DT_UNKNOWN;
 255
 256        /* Convert to NLS */
 257        if (BEFS_SB(sb)->nls) {
 258                char *nlsname;
 259                int nlsnamelen;
 260                result =
 261                    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
 262                if (result < 0) {
 263                        befs_debug(sb, "<--- befs_readdir() ERROR");
 264                        return result;
 265                }
 266                if (!dir_emit(ctx, nlsname, nlsnamelen,
 267                                 (ino_t) value, d_type)) {
 268                        kfree(nlsname);
 269                        return 0;
 270                }
 271                kfree(nlsname);
 272        } else {
 273                if (!dir_emit(ctx, keybuf, keysize,
 274                                 (ino_t) value, d_type))
 275                        return 0;
 276        }
 277        ctx->pos++;
 278        goto more;
 279
 280        befs_debug(sb, "<--- befs_readdir() pos %Ld", ctx->pos);
 281
 282        return 0;
 283}
 284
 285static struct inode *
 286befs_alloc_inode(struct super_block *sb)
 287{
 288        struct befs_inode_info *bi;
 289        bi = (struct befs_inode_info *)kmem_cache_alloc(befs_inode_cachep,
 290                                                        GFP_KERNEL);
 291        if (!bi)
 292                return NULL;
 293        return &bi->vfs_inode;
 294}
 295
 296static void befs_i_callback(struct rcu_head *head)
 297{
 298        struct inode *inode = container_of(head, struct inode, i_rcu);
 299        kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
 300}
 301
 302static void befs_destroy_inode(struct inode *inode)
 303{
 304        call_rcu(&inode->i_rcu, befs_i_callback);
 305}
 306
 307static void init_once(void *foo)
 308{
 309        struct befs_inode_info *bi = (struct befs_inode_info *) foo;
 310
 311        inode_init_once(&bi->vfs_inode);
 312}
 313
 314static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
 315{
 316        struct buffer_head *bh = NULL;
 317        befs_inode *raw_inode = NULL;
 318
 319        befs_sb_info *befs_sb = BEFS_SB(sb);
 320        befs_inode_info *befs_ino = NULL;
 321        struct inode *inode;
 322        long ret = -EIO;
 323
 324        befs_debug(sb, "---> befs_read_inode() " "inode = %lu", ino);
 325
 326        inode = iget_locked(sb, ino);
 327        if (!inode)
 328                return ERR_PTR(-ENOMEM);
 329        if (!(inode->i_state & I_NEW))
 330                return inode;
 331
 332        befs_ino = BEFS_I(inode);
 333
 334        /* convert from vfs's inode number to befs's inode number */
 335        befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
 336
 337        befs_debug(sb, "  real inode number [%u, %hu, %hu]",
 338                   befs_ino->i_inode_num.allocation_group,
 339                   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
 340
 341        bh = befs_bread(sb, inode->i_ino);
 342        if (!bh) {
 343                befs_error(sb, "unable to read inode block - "
 344                           "inode = %lu", inode->i_ino);
 345                goto unacquire_none;
 346        }
 347
 348        raw_inode = (befs_inode *) bh->b_data;
 349
 350        befs_dump_inode(sb, raw_inode);
 351
 352        if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
 353                befs_error(sb, "Bad inode: %lu", inode->i_ino);
 354                goto unacquire_bh;
 355        }
 356
 357        inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
 358
 359        /*
 360         * set uid and gid.  But since current BeOS is single user OS, so
 361         * you can change by "uid" or "gid" options.
 362         */   
 363
 364        inode->i_uid = befs_sb->mount_opts.use_uid ?
 365                befs_sb->mount_opts.uid :
 366                make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
 367        inode->i_gid = befs_sb->mount_opts.use_gid ?
 368                befs_sb->mount_opts.gid :
 369                make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
 370
 371        set_nlink(inode, 1);
 372
 373        /*
 374         * BEFS's time is 64 bits, but current VFS is 32 bits...
 375         * BEFS don't have access time. Nor inode change time. VFS
 376         * doesn't have creation time.
 377         * Also, the lower 16 bits of the last_modified_time and 
 378         * create_time are just a counter to help ensure uniqueness
 379         * for indexing purposes. (PFD, page 54)
 380         */
 381
 382        inode->i_mtime.tv_sec =
 383            fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
 384        inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */        
 385        inode->i_ctime = inode->i_mtime;
 386        inode->i_atime = inode->i_mtime;
 387
 388        befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
 389        befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
 390        befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
 391        befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
 392
 393        if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
 394                inode->i_size = 0;
 395                inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
 396                strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
 397                        BEFS_SYMLINK_LEN - 1);
 398                befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
 399        } else {
 400                int num_blks;
 401
 402                befs_ino->i_data.ds =
 403                    fsds_to_cpu(sb, &raw_inode->data.datastream);
 404
 405                num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
 406                inode->i_blocks =
 407                    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
 408                inode->i_size = befs_ino->i_data.ds.size;
 409        }
 410
 411        inode->i_mapping->a_ops = &befs_aops;
 412
 413        if (S_ISREG(inode->i_mode)) {
 414                inode->i_fop = &generic_ro_fops;
 415        } else if (S_ISDIR(inode->i_mode)) {
 416                inode->i_op = &befs_dir_inode_operations;
 417                inode->i_fop = &befs_dir_operations;
 418        } else if (S_ISLNK(inode->i_mode)) {
 419                if (befs_ino->i_flags & BEFS_LONG_SYMLINK)
 420                        inode->i_op = &befs_symlink_inode_operations;
 421                else
 422                        inode->i_op = &befs_fast_symlink_inode_operations;
 423        } else {
 424                befs_error(sb, "Inode %lu is not a regular file, "
 425                           "directory or symlink. THAT IS WRONG! BeFS has no "
 426                           "on disk special files", inode->i_ino);
 427                goto unacquire_bh;
 428        }
 429
 430        brelse(bh);
 431        befs_debug(sb, "<--- befs_read_inode()");
 432        unlock_new_inode(inode);
 433        return inode;
 434
 435      unacquire_bh:
 436        brelse(bh);
 437
 438      unacquire_none:
 439        iget_failed(inode);
 440        befs_debug(sb, "<--- befs_read_inode() - Bad inode");
 441        return ERR_PTR(ret);
 442}
 443
 444/* Initialize the inode cache. Called at fs setup.
 445 *
 446 * Taken from NFS implementation by Al Viro.
 447 */
 448static int
 449befs_init_inodecache(void)
 450{
 451        befs_inode_cachep = kmem_cache_create("befs_inode_cache",
 452                                              sizeof (struct befs_inode_info),
 453                                              0, (SLAB_RECLAIM_ACCOUNT|
 454                                                SLAB_MEM_SPREAD),
 455                                              init_once);
 456        if (befs_inode_cachep == NULL) {
 457                printk(KERN_ERR "befs_init_inodecache: "
 458                       "Couldn't initialize inode slabcache\n");
 459                return -ENOMEM;
 460        }
 461
 462        return 0;
 463}
 464
 465/* Called at fs teardown.
 466 * 
 467 * Taken from NFS implementation by Al Viro.
 468 */
 469static void
 470befs_destroy_inodecache(void)
 471{
 472        /*
 473         * Make sure all delayed rcu free inodes are flushed before we
 474         * destroy cache.
 475         */
 476        rcu_barrier();
 477        kmem_cache_destroy(befs_inode_cachep);
 478}
 479
 480/*
 481 * The inode of symbolic link is different to data stream.
 482 * The data stream become link name. Unless the LONG_SYMLINK
 483 * flag is set.
 484 */
 485static void *
 486befs_follow_link(struct dentry *dentry, struct nameidata *nd)
 487{
 488        struct super_block *sb = dentry->d_sb;
 489        befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
 490        befs_data_stream *data = &befs_ino->i_data.ds;
 491        befs_off_t len = data->size;
 492        char *link;
 493
 494        if (len == 0) {
 495                befs_error(sb, "Long symlink with illegal length");
 496                link = ERR_PTR(-EIO);
 497        } else {
 498                befs_debug(sb, "Follow long symlink");
 499
 500                link = kmalloc(len, GFP_NOFS);
 501                if (!link) {
 502                        link = ERR_PTR(-ENOMEM);
 503                } else if (befs_read_lsymlink(sb, data, link, len) != len) {
 504                        kfree(link);
 505                        befs_error(sb, "Failed to read entire long symlink");
 506                        link = ERR_PTR(-EIO);
 507                } else {
 508                        link[len - 1] = '\0';
 509                }
 510        }
 511        nd_set_link(nd, link);
 512        return NULL;
 513}
 514
 515
 516static void *
 517befs_fast_follow_link(struct dentry *dentry, struct nameidata *nd)
 518{
 519        befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
 520        nd_set_link(nd, befs_ino->i_data.symlink);
 521        return NULL;
 522}
 523
 524/*
 525 * UTF-8 to NLS charset  convert routine
 526 * 
 527 *
 528 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
 529 * the nls tables directly
 530 */
 531
 532static int
 533befs_utf2nls(struct super_block *sb, const char *in,
 534             int in_len, char **out, int *out_len)
 535{
 536        struct nls_table *nls = BEFS_SB(sb)->nls;
 537        int i, o;
 538        unicode_t uni;
 539        int unilen, utflen;
 540        char *result;
 541        /* The utf8->nls conversion won't make the final nls string bigger
 542         * than the utf one, but if the string is pure ascii they'll have the
 543         * same width and an extra char is needed to save the additional \0
 544         */
 545        int maxlen = in_len + 1;
 546
 547        befs_debug(sb, "---> utf2nls()");
 548
 549        if (!nls) {
 550                befs_error(sb, "befs_utf2nls called with no NLS table loaded");
 551                return -EINVAL;
 552        }
 553
 554        *out = result = kmalloc(maxlen, GFP_NOFS);
 555        if (!*out) {
 556                befs_error(sb, "befs_utf2nls() cannot allocate memory");
 557                *out_len = 0;
 558                return -ENOMEM;
 559        }
 560
 561        for (i = o = 0; i < in_len; i += utflen, o += unilen) {
 562
 563                /* convert from UTF-8 to Unicode */
 564                utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
 565                if (utflen < 0)
 566                        goto conv_err;
 567
 568                /* convert from Unicode to nls */
 569                if (uni > MAX_WCHAR_T)
 570                        goto conv_err;
 571                unilen = nls->uni2char(uni, &result[o], in_len - o);
 572                if (unilen < 0)
 573                        goto conv_err;
 574        }
 575        result[o] = '\0';
 576        *out_len = o;
 577
 578        befs_debug(sb, "<--- utf2nls()");
 579
 580        return o;
 581
 582      conv_err:
 583        befs_error(sb, "Name using character set %s contains a character that "
 584                   "cannot be converted to unicode.", nls->charset);
 585        befs_debug(sb, "<--- utf2nls()");
 586        kfree(result);
 587        return -EILSEQ;
 588}
 589
 590/**
 591 * befs_nls2utf - Convert NLS string to utf8 encodeing
 592 * @sb: Superblock
 593 * @src: Input string buffer in NLS format
 594 * @srclen: Length of input string in bytes
 595 * @dest: The output string in UTF-8 format
 596 * @destlen: Length of the output buffer
 597 * 
 598 * Converts input string @src, which is in the format of the loaded NLS map,
 599 * into a utf8 string.
 600 * 
 601 * The destination string @dest is allocated by this function and the caller is
 602 * responsible for freeing it with kfree()
 603 * 
 604 * On return, *@destlen is the length of @dest in bytes.
 605 *
 606 * On success, the return value is the number of utf8 characters written to
 607 * the output buffer @dest.
 608 *  
 609 * On Failure, a negative number coresponding to the error code is returned.
 610 */
 611
 612static int
 613befs_nls2utf(struct super_block *sb, const char *in,
 614             int in_len, char **out, int *out_len)
 615{
 616        struct nls_table *nls = BEFS_SB(sb)->nls;
 617        int i, o;
 618        wchar_t uni;
 619        int unilen, utflen;
 620        char *result;
 621        /* There're nls characters that will translate to 3-chars-wide UTF-8
 622         * characters, a additional byte is needed to save the final \0
 623         * in special cases */
 624        int maxlen = (3 * in_len) + 1;
 625
 626        befs_debug(sb, "---> nls2utf()\n");
 627
 628        if (!nls) {
 629                befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
 630                return -EINVAL;
 631        }
 632
 633        *out = result = kmalloc(maxlen, GFP_NOFS);
 634        if (!*out) {
 635                befs_error(sb, "befs_nls2utf() cannot allocate memory");
 636                *out_len = 0;
 637                return -ENOMEM;
 638        }
 639
 640        for (i = o = 0; i < in_len; i += unilen, o += utflen) {
 641
 642                /* convert from nls to unicode */
 643                unilen = nls->char2uni(&in[i], in_len - i, &uni);
 644                if (unilen < 0)
 645                        goto conv_err;
 646
 647                /* convert from unicode to UTF-8 */
 648                utflen = utf32_to_utf8(uni, &result[o], 3);
 649                if (utflen <= 0)
 650                        goto conv_err;
 651        }
 652
 653        result[o] = '\0';
 654        *out_len = o;
 655
 656        befs_debug(sb, "<--- nls2utf()");
 657
 658        return i;
 659
 660      conv_err:
 661        befs_error(sb, "Name using charecter set %s contains a charecter that "
 662                   "cannot be converted to unicode.", nls->charset);
 663        befs_debug(sb, "<--- nls2utf()");
 664        kfree(result);
 665        return -EILSEQ;
 666}
 667
 668/**
 669 * Use the
 670 *
 671 */
 672enum {
 673        Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
 674};
 675
 676static const match_table_t befs_tokens = {
 677        {Opt_uid, "uid=%d"},
 678        {Opt_gid, "gid=%d"},
 679        {Opt_charset, "iocharset=%s"},
 680        {Opt_debug, "debug"},
 681        {Opt_err, NULL}
 682};
 683
 684static int
 685parse_options(char *options, befs_mount_options * opts)
 686{
 687        char *p;
 688        substring_t args[MAX_OPT_ARGS];
 689        int option;
 690        kuid_t uid;
 691        kgid_t gid;
 692
 693        /* Initialize options */
 694        opts->uid = GLOBAL_ROOT_UID;
 695        opts->gid = GLOBAL_ROOT_GID;
 696        opts->use_uid = 0;
 697        opts->use_gid = 0;
 698        opts->iocharset = NULL;
 699        opts->debug = 0;
 700
 701        if (!options)
 702                return 1;
 703
 704        while ((p = strsep(&options, ",")) != NULL) {
 705                int token;
 706                if (!*p)
 707                        continue;
 708
 709                token = match_token(p, befs_tokens, args);
 710                switch (token) {
 711                case Opt_uid:
 712                        if (match_int(&args[0], &option))
 713                                return 0;
 714                        uid = INVALID_UID;
 715                        if (option >= 0)
 716                                uid = make_kuid(current_user_ns(), option);
 717                        if (!uid_valid(uid)) {
 718                                printk(KERN_ERR "BeFS: Invalid uid %d, "
 719                                                "using default\n", option);
 720                                break;
 721                        }
 722                        opts->uid = uid;
 723                        opts->use_uid = 1;
 724                        break;
 725                case Opt_gid:
 726                        if (match_int(&args[0], &option))
 727                                return 0;
 728                        gid = INVALID_GID;
 729                        if (option >= 0)
 730                                gid = make_kgid(current_user_ns(), option);
 731                        if (!gid_valid(gid)) {
 732                                printk(KERN_ERR "BeFS: Invalid gid %d, "
 733                                                "using default\n", option);
 734                                break;
 735                        }
 736                        opts->gid = gid;
 737                        opts->use_gid = 1;
 738                        break;
 739                case Opt_charset:
 740                        kfree(opts->iocharset);
 741                        opts->iocharset = match_strdup(&args[0]);
 742                        if (!opts->iocharset) {
 743                                printk(KERN_ERR "BeFS: allocation failure for "
 744                                                "iocharset string\n");
 745                                return 0;
 746                        }
 747                        break;
 748                case Opt_debug:
 749                        opts->debug = 1;
 750                        break;
 751                default:
 752                        printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
 753                                        "or missing value\n", p);
 754                        return 0;
 755                }
 756        }
 757        return 1;
 758}
 759
 760/* This function has the responsibiltiy of getting the
 761 * filesystem ready for unmounting. 
 762 * Basically, we free everything that we allocated in
 763 * befs_read_inode
 764 */
 765static void
 766befs_put_super(struct super_block *sb)
 767{
 768        kfree(BEFS_SB(sb)->mount_opts.iocharset);
 769        BEFS_SB(sb)->mount_opts.iocharset = NULL;
 770        unload_nls(BEFS_SB(sb)->nls);
 771        kfree(sb->s_fs_info);
 772        sb->s_fs_info = NULL;
 773}
 774
 775/* Allocate private field of the superblock, fill it.
 776 *
 777 * Finish filling the public superblock fields
 778 * Make the root directory
 779 * Load a set of NLS translations if needed.
 780 */
 781static int
 782befs_fill_super(struct super_block *sb, void *data, int silent)
 783{
 784        struct buffer_head *bh;
 785        befs_sb_info *befs_sb;
 786        befs_super_block *disk_sb;
 787        struct inode *root;
 788        long ret = -EINVAL;
 789        const unsigned long sb_block = 0;
 790        const off_t x86_sb_off = 512;
 791
 792        save_mount_options(sb, data);
 793
 794        sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
 795        if (sb->s_fs_info == NULL) {
 796                printk(KERN_ERR
 797                       "BeFS(%s): Unable to allocate memory for private "
 798                       "portion of superblock. Bailing.\n", sb->s_id);
 799                goto unacquire_none;
 800        }
 801        befs_sb = BEFS_SB(sb);
 802        memset(befs_sb, 0, sizeof(befs_sb_info));
 803
 804        if (!parse_options((char *) data, &befs_sb->mount_opts)) {
 805                befs_error(sb, "cannot parse mount options");
 806                goto unacquire_priv_sbp;
 807        }
 808
 809        befs_debug(sb, "---> befs_fill_super()");
 810
 811#ifndef CONFIG_BEFS_RW
 812        if (!(sb->s_flags & MS_RDONLY)) {
 813                befs_warning(sb,
 814                             "No write support. Marking filesystem read-only");
 815                sb->s_flags |= MS_RDONLY;
 816        }
 817#endif                          /* CONFIG_BEFS_RW */
 818
 819        /*
 820         * Set dummy blocksize to read super block.
 821         * Will be set to real fs blocksize later.
 822         *
 823         * Linux 2.4.10 and later refuse to read blocks smaller than
 824         * the hardsect size for the device. But we also need to read at 
 825         * least 1k to get the second 512 bytes of the volume.
 826         * -WD 10-26-01
 827         */ 
 828        sb_min_blocksize(sb, 1024);
 829
 830        if (!(bh = sb_bread(sb, sb_block))) {
 831                befs_error(sb, "unable to read superblock");
 832                goto unacquire_priv_sbp;
 833        }
 834
 835        /* account for offset of super block on x86 */
 836        disk_sb = (befs_super_block *) bh->b_data;
 837        if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
 838            (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
 839                befs_debug(sb, "Using PPC superblock location");
 840        } else {
 841                befs_debug(sb, "Using x86 superblock location");
 842                disk_sb =
 843                    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
 844        }
 845
 846        if (befs_load_sb(sb, disk_sb) != BEFS_OK)
 847                goto unacquire_bh;
 848
 849        befs_dump_super_block(sb, disk_sb);
 850
 851        brelse(bh);
 852
 853        if (befs_check_sb(sb) != BEFS_OK)
 854                goto unacquire_priv_sbp;
 855
 856        if( befs_sb->num_blocks > ~((sector_t)0) ) {
 857                befs_error(sb, "blocks count: %Lu "
 858                        "is larger than the host can use",
 859                        befs_sb->num_blocks);
 860                goto unacquire_priv_sbp;
 861        }
 862
 863        /*
 864         * set up enough so that it can read an inode
 865         * Fill in kernel superblock fields from private sb
 866         */
 867        sb->s_magic = BEFS_SUPER_MAGIC;
 868        /* Set real blocksize of fs */
 869        sb_set_blocksize(sb, (ulong) befs_sb->block_size);
 870        sb->s_op = &befs_sops;
 871        root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
 872        if (IS_ERR(root)) {
 873                ret = PTR_ERR(root);
 874                goto unacquire_priv_sbp;
 875        }
 876        sb->s_root = d_make_root(root);
 877        if (!sb->s_root) {
 878                befs_error(sb, "get root inode failed");
 879                goto unacquire_priv_sbp;
 880        }
 881
 882        /* load nls library */
 883        if (befs_sb->mount_opts.iocharset) {
 884                befs_debug(sb, "Loading nls: %s",
 885                           befs_sb->mount_opts.iocharset);
 886                befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
 887                if (!befs_sb->nls) {
 888                        befs_warning(sb, "Cannot load nls %s"
 889                                        " loading default nls",
 890                                        befs_sb->mount_opts.iocharset);
 891                        befs_sb->nls = load_nls_default();
 892                }
 893        /* load default nls if none is specified  in mount options */
 894        } else {
 895                befs_debug(sb, "Loading default nls");
 896                befs_sb->nls = load_nls_default();
 897        }
 898
 899        return 0;
 900/*****************/
 901      unacquire_bh:
 902        brelse(bh);
 903
 904      unacquire_priv_sbp:
 905        kfree(befs_sb->mount_opts.iocharset);
 906        kfree(sb->s_fs_info);
 907
 908      unacquire_none:
 909        sb->s_fs_info = NULL;
 910        return ret;
 911}
 912
 913static int
 914befs_remount(struct super_block *sb, int *flags, char *data)
 915{
 916        if (!(*flags & MS_RDONLY))
 917                return -EINVAL;
 918        return 0;
 919}
 920
 921static int
 922befs_statfs(struct dentry *dentry, struct kstatfs *buf)
 923{
 924        struct super_block *sb = dentry->d_sb;
 925        u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 926
 927        befs_debug(sb, "---> befs_statfs()");
 928
 929        buf->f_type = BEFS_SUPER_MAGIC;
 930        buf->f_bsize = sb->s_blocksize;
 931        buf->f_blocks = BEFS_SB(sb)->num_blocks;
 932        buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
 933        buf->f_bavail = buf->f_bfree;
 934        buf->f_files = 0;       /* UNKNOWN */
 935        buf->f_ffree = 0;       /* UNKNOWN */
 936        buf->f_fsid.val[0] = (u32)id;
 937        buf->f_fsid.val[1] = (u32)(id >> 32);
 938        buf->f_namelen = BEFS_NAME_LEN;
 939
 940        befs_debug(sb, "<--- befs_statfs()");
 941
 942        return 0;
 943}
 944
 945static struct dentry *
 946befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
 947            void *data)
 948{
 949        return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
 950}
 951
 952static struct file_system_type befs_fs_type = {
 953        .owner          = THIS_MODULE,
 954        .name           = "befs",
 955        .mount          = befs_mount,
 956        .kill_sb        = kill_block_super,
 957        .fs_flags       = FS_REQUIRES_DEV,      
 958};
 959MODULE_ALIAS_FS("befs");
 960
 961static int __init
 962init_befs_fs(void)
 963{
 964        int err;
 965
 966        printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
 967
 968        err = befs_init_inodecache();
 969        if (err)
 970                goto unacquire_none;
 971
 972        err = register_filesystem(&befs_fs_type);
 973        if (err)
 974                goto unacquire_inodecache;
 975
 976        return 0;
 977
 978unacquire_inodecache:
 979        befs_destroy_inodecache();
 980
 981unacquire_none:
 982        return err;
 983}
 984
 985static void __exit
 986exit_befs_fs(void)
 987{
 988        befs_destroy_inodecache();
 989
 990        unregister_filesystem(&befs_fs_type);
 991}
 992
 993/*
 994Macros that typecheck the init and exit functions,
 995ensures that they are called at init and cleanup,
 996and eliminates warnings about unused functions.
 997*/
 998module_init(init_befs_fs)
 999module_exit(exit_befs_fs)
1000
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