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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * linux/fs/befs/linuxvfs.c4 *5 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com6 *7 */8 9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt10 11#include <linux/module.h>12#include <linux/slab.h>13#include <linux/fs.h>14#include <linux/errno.h>15#include <linux/stat.h>16#include <linux/nls.h>17#include <linux/buffer_head.h>18#include <linux/vfs.h>19#include <linux/parser.h>20#include <linux/namei.h>21#include <linux/sched.h>22#include <linux/cred.h>23#include <linux/exportfs.h>24#include <linux/seq_file.h>25#include <linux/blkdev.h>26 27#include "befs.h"28#include "btree.h"29#include "inode.h"30#include "datastream.h"31#include "super.h"32#include "io.h"33 34MODULE_DESCRIPTION("BeOS File System (BeFS) driver");35MODULE_AUTHOR("Will Dyson");36MODULE_LICENSE("GPL");37 38/* The units the vfs expects inode->i_blocks to be in */39#define VFS_BLOCK_SIZE 51240 41static int befs_readdir(struct file *, struct dir_context *);42static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);43static int befs_read_folio(struct file *file, struct folio *folio);44static sector_t befs_bmap(struct address_space *mapping, sector_t block);45static struct dentry *befs_lookup(struct inode *, struct dentry *,46 unsigned int);47static struct inode *befs_iget(struct super_block *, unsigned long);48static struct inode *befs_alloc_inode(struct super_block *sb);49static void befs_free_inode(struct inode *inode);50static void befs_destroy_inodecache(void);51static int befs_symlink_read_folio(struct file *, struct folio *);52static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,53 char **out, int *out_len);54static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,55 char **out, int *out_len);56static void befs_put_super(struct super_block *);57static int befs_remount(struct super_block *, int *, char *);58static int befs_statfs(struct dentry *, struct kstatfs *);59static int befs_show_options(struct seq_file *, struct dentry *);60static int parse_options(char *, struct befs_mount_options *);61static struct dentry *befs_fh_to_dentry(struct super_block *sb,62 struct fid *fid, int fh_len, int fh_type);63static struct dentry *befs_fh_to_parent(struct super_block *sb,64 struct fid *fid, int fh_len, int fh_type);65static struct dentry *befs_get_parent(struct dentry *child);66 67static const struct super_operations befs_sops = {68 .alloc_inode = befs_alloc_inode, /* allocate a new inode */69 .free_inode = befs_free_inode, /* deallocate an inode */70 .put_super = befs_put_super, /* uninit super */71 .statfs = befs_statfs, /* statfs */72 .remount_fs = befs_remount,73 .show_options = befs_show_options,74};75 76/* slab cache for befs_inode_info objects */77static struct kmem_cache *befs_inode_cachep;78 79static const struct file_operations befs_dir_operations = {80 .read = generic_read_dir,81 .iterate_shared = befs_readdir,82 .llseek = generic_file_llseek,83};84 85static const struct inode_operations befs_dir_inode_operations = {86 .lookup = befs_lookup,87};88 89static const struct address_space_operations befs_aops = {90 .read_folio = befs_read_folio,91 .bmap = befs_bmap,92};93 94static const struct address_space_operations befs_symlink_aops = {95 .read_folio = befs_symlink_read_folio,96};97 98static const struct export_operations befs_export_operations = {99 .encode_fh = generic_encode_ino32_fh,100 .fh_to_dentry = befs_fh_to_dentry,101 .fh_to_parent = befs_fh_to_parent,102 .get_parent = befs_get_parent,103};104 105/*106 * Called by generic_file_read() to read a folio of data107 *108 * In turn, simply calls a generic block read function and109 * passes it the address of befs_get_block, for mapping file110 * positions to disk blocks.111 */112static int befs_read_folio(struct file *file, struct folio *folio)113{114 return block_read_full_folio(folio, befs_get_block);115}116 117static sector_t118befs_bmap(struct address_space *mapping, sector_t block)119{120 return generic_block_bmap(mapping, block, befs_get_block);121}122 123/*124 * Generic function to map a file position (block) to a125 * disk offset (passed back in bh_result).126 *127 * Used by many higher level functions.128 *129 * Calls befs_fblock2brun() in datastream.c to do the real work.130 */131 132static int133befs_get_block(struct inode *inode, sector_t block,134 struct buffer_head *bh_result, int create)135{136 struct super_block *sb = inode->i_sb;137 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;138 befs_block_run run = BAD_IADDR;139 int res;140 ulong disk_off;141 142 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",143 (unsigned long)inode->i_ino, (long)block);144 if (create) {145 befs_error(sb, "befs_get_block() was asked to write to "146 "block %ld in inode %lu", (long)block,147 (unsigned long)inode->i_ino);148 return -EPERM;149 }150 151 res = befs_fblock2brun(sb, ds, block, &run);152 if (res != BEFS_OK) {153 befs_error(sb,154 "<--- %s for inode %lu, block %ld ERROR",155 __func__, (unsigned long)inode->i_ino,156 (long)block);157 return -EFBIG;158 }159 160 disk_off = (ulong) iaddr2blockno(sb, &run);161 162 map_bh(bh_result, inode->i_sb, disk_off);163 164 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",165 __func__, (unsigned long)inode->i_ino, (long)block,166 (unsigned long)disk_off);167 168 return 0;169}170 171static struct dentry *172befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)173{174 struct inode *inode;175 struct super_block *sb = dir->i_sb;176 const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;177 befs_off_t offset;178 int ret;179 int utfnamelen;180 char *utfname;181 const char *name = dentry->d_name.name;182 183 befs_debug(sb, "---> %s name %pd inode %ld", __func__,184 dentry, dir->i_ino);185 186 /* Convert to UTF-8 */187 if (BEFS_SB(sb)->nls) {188 ret =189 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);190 if (ret < 0) {191 befs_debug(sb, "<--- %s ERROR", __func__);192 return ERR_PTR(ret);193 }194 ret = befs_btree_find(sb, ds, utfname, &offset);195 kfree(utfname);196 197 } else {198 ret = befs_btree_find(sb, ds, name, &offset);199 }200 201 if (ret == BEFS_BT_NOT_FOUND) {202 befs_debug(sb, "<--- %s %pd not found", __func__, dentry);203 inode = NULL;204 } else if (ret != BEFS_OK || offset == 0) {205 befs_error(sb, "<--- %s Error", __func__);206 inode = ERR_PTR(-ENODATA);207 } else {208 inode = befs_iget(dir->i_sb, (ino_t) offset);209 }210 befs_debug(sb, "<--- %s", __func__);211 212 return d_splice_alias(inode, dentry);213}214 215static int216befs_readdir(struct file *file, struct dir_context *ctx)217{218 struct inode *inode = file_inode(file);219 struct super_block *sb = inode->i_sb;220 const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;221 befs_off_t value;222 int result;223 size_t keysize;224 char keybuf[BEFS_NAME_LEN + 1];225 226 befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld",227 __func__, file, inode->i_ino, ctx->pos);228 229 while (1) {230 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,231 keybuf, &keysize, &value);232 233 if (result == BEFS_ERR) {234 befs_debug(sb, "<--- %s ERROR", __func__);235 befs_error(sb, "IO error reading %pD (inode %lu)",236 file, inode->i_ino);237 return -EIO;238 239 } else if (result == BEFS_BT_END) {240 befs_debug(sb, "<--- %s END", __func__);241 return 0;242 243 } else if (result == BEFS_BT_EMPTY) {244 befs_debug(sb, "<--- %s Empty directory", __func__);245 return 0;246 }247 248 /* Convert to NLS */249 if (BEFS_SB(sb)->nls) {250 char *nlsname;251 int nlsnamelen;252 253 result =254 befs_utf2nls(sb, keybuf, keysize, &nlsname,255 &nlsnamelen);256 if (result < 0) {257 befs_debug(sb, "<--- %s ERROR", __func__);258 return result;259 }260 if (!dir_emit(ctx, nlsname, nlsnamelen,261 (ino_t) value, DT_UNKNOWN)) {262 kfree(nlsname);263 return 0;264 }265 kfree(nlsname);266 } else {267 if (!dir_emit(ctx, keybuf, keysize,268 (ino_t) value, DT_UNKNOWN))269 return 0;270 }271 ctx->pos++;272 }273}274 275static struct inode *276befs_alloc_inode(struct super_block *sb)277{278 struct befs_inode_info *bi;279 280 bi = alloc_inode_sb(sb, befs_inode_cachep, GFP_KERNEL);281 if (!bi)282 return NULL;283 return &bi->vfs_inode;284}285 286static void befs_free_inode(struct inode *inode)287{288 kmem_cache_free(befs_inode_cachep, BEFS_I(inode));289}290 291static void init_once(void *foo)292{293 struct befs_inode_info *bi = (struct befs_inode_info *) foo;294 295 inode_init_once(&bi->vfs_inode);296}297 298static struct inode *befs_iget(struct super_block *sb, unsigned long ino)299{300 struct buffer_head *bh;301 befs_inode *raw_inode;302 struct befs_sb_info *befs_sb = BEFS_SB(sb);303 struct befs_inode_info *befs_ino;304 struct inode *inode;305 306 befs_debug(sb, "---> %s inode = %lu", __func__, ino);307 308 inode = iget_locked(sb, ino);309 if (!inode)310 return ERR_PTR(-ENOMEM);311 if (!(inode->i_state & I_NEW))312 return inode;313 314 befs_ino = BEFS_I(inode);315 316 /* convert from vfs's inode number to befs's inode number */317 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);318 319 befs_debug(sb, " real inode number [%u, %hu, %hu]",320 befs_ino->i_inode_num.allocation_group,321 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);322 323 bh = sb_bread(sb, inode->i_ino);324 if (!bh) {325 befs_error(sb, "unable to read inode block - "326 "inode = %lu", inode->i_ino);327 goto unacquire_none;328 }329 330 raw_inode = (befs_inode *) bh->b_data;331 332 befs_dump_inode(sb, raw_inode);333 334 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {335 befs_error(sb, "Bad inode: %lu", inode->i_ino);336 goto unacquire_bh;337 }338 339 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);340 341 /*342 * set uid and gid. But since current BeOS is single user OS, so343 * you can change by "uid" or "gid" options.344 */345 346 inode->i_uid = befs_sb->mount_opts.use_uid ?347 befs_sb->mount_opts.uid :348 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));349 inode->i_gid = befs_sb->mount_opts.use_gid ?350 befs_sb->mount_opts.gid :351 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));352 353 set_nlink(inode, 1);354 355 /*356 * BEFS's time is 64 bits, but current VFS is 32 bits...357 * BEFS don't have access time. Nor inode change time. VFS358 * doesn't have creation time.359 * Also, the lower 16 bits of the last_modified_time and360 * create_time are just a counter to help ensure uniqueness361 * for indexing purposes. (PFD, page 54)362 */363 364 inode_set_mtime(inode,365 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16,366 0);/* lower 16 bits are not a time */367 inode_set_ctime_to_ts(inode, inode_get_mtime(inode));368 inode_set_atime_to_ts(inode, inode_get_mtime(inode));369 370 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);371 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);372 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);373 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);374 375 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){376 inode->i_size = 0;377 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;378 strscpy(befs_ino->i_data.symlink, raw_inode->data.symlink,379 BEFS_SYMLINK_LEN);380 } else {381 int num_blks;382 383 befs_ino->i_data.ds =384 fsds_to_cpu(sb, &raw_inode->data.datastream);385 386 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);387 inode->i_blocks =388 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);389 inode->i_size = befs_ino->i_data.ds.size;390 }391 392 inode->i_mapping->a_ops = &befs_aops;393 394 if (S_ISREG(inode->i_mode)) {395 inode->i_fop = &generic_ro_fops;396 } else if (S_ISDIR(inode->i_mode)) {397 inode->i_op = &befs_dir_inode_operations;398 inode->i_fop = &befs_dir_operations;399 } else if (S_ISLNK(inode->i_mode)) {400 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {401 inode->i_op = &page_symlink_inode_operations;402 inode_nohighmem(inode);403 inode->i_mapping->a_ops = &befs_symlink_aops;404 } else {405 inode->i_link = befs_ino->i_data.symlink;406 inode->i_op = &simple_symlink_inode_operations;407 }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, "<--- %s", __func__);417 unlock_new_inode(inode);418 return inode;419 420unacquire_bh:421 brelse(bh);422 423unacquire_none:424 iget_failed(inode);425 befs_debug(sb, "<--- %s - Bad inode", __func__);426 return ERR_PTR(-EIO);427}428 429/* Initialize the inode cache. Called at fs setup.430 *431 * Taken from NFS implementation by Al Viro.432 */433static int __init434befs_init_inodecache(void)435{436 befs_inode_cachep = kmem_cache_create_usercopy("befs_inode_cache",437 sizeof(struct befs_inode_info), 0,438 SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,439 offsetof(struct befs_inode_info,440 i_data.symlink),441 sizeof_field(struct befs_inode_info,442 i_data.symlink),443 init_once);444 if (befs_inode_cachep == NULL)445 return -ENOMEM;446 447 return 0;448}449 450/* Called at fs teardown.451 *452 * Taken from NFS implementation by Al Viro.453 */454static void455befs_destroy_inodecache(void)456{457 /*458 * Make sure all delayed rcu free inodes are flushed before we459 * destroy cache.460 */461 rcu_barrier();462 kmem_cache_destroy(befs_inode_cachep);463}464 465/*466 * The inode of symbolic link is different to data stream.467 * The data stream become link name. Unless the LONG_SYMLINK468 * flag is set.469 */470static int befs_symlink_read_folio(struct file *unused, struct folio *folio)471{472 struct inode *inode = folio->mapping->host;473 struct super_block *sb = inode->i_sb;474 struct befs_inode_info *befs_ino = BEFS_I(inode);475 befs_data_stream *data = &befs_ino->i_data.ds;476 befs_off_t len = data->size;477 char *link = folio_address(folio);478 int err = -EIO;479 480 if (len == 0 || len > PAGE_SIZE) {481 befs_error(sb, "Long symlink with illegal length");482 goto fail;483 }484 befs_debug(sb, "Follow long symlink");485 486 if (befs_read_lsymlink(sb, data, link, len) != len) {487 befs_error(sb, "Failed to read entire long symlink");488 goto fail;489 }490 link[len - 1] = '\0';491 err = 0;492fail:493 folio_end_read(folio, err == 0);494 return err;495}496 497/*498 * UTF-8 to NLS charset convert routine499 *500 * Uses uni2char() / char2uni() rather than the nls tables directly501 */502static int503befs_utf2nls(struct super_block *sb, const char *in,504 int in_len, char **out, int *out_len)505{506 struct nls_table *nls = BEFS_SB(sb)->nls;507 int i, o;508 unicode_t uni;509 int unilen, utflen;510 char *result;511 /* The utf8->nls conversion won't make the final nls string bigger512 * than the utf one, but if the string is pure ascii they'll have the513 * same width and an extra char is needed to save the additional \0514 */515 int maxlen = in_len + 1;516 517 befs_debug(sb, "---> %s", __func__);518 519 if (!nls) {520 befs_error(sb, "%s called with no NLS table loaded", __func__);521 return -EINVAL;522 }523 524 *out = result = kmalloc(maxlen, GFP_NOFS);525 if (!*out)526 return -ENOMEM;527 528 for (i = o = 0; i < in_len; i += utflen, o += unilen) {529 530 /* convert from UTF-8 to Unicode */531 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);532 if (utflen < 0)533 goto conv_err;534 535 /* convert from Unicode to nls */536 if (uni > MAX_WCHAR_T)537 goto conv_err;538 unilen = nls->uni2char(uni, &result[o], in_len - o);539 if (unilen < 0)540 goto conv_err;541 }542 result[o] = '\0';543 *out_len = o;544 545 befs_debug(sb, "<--- %s", __func__);546 547 return o;548 549conv_err:550 befs_error(sb, "Name using character set %s contains a character that "551 "cannot be converted to unicode.", nls->charset);552 befs_debug(sb, "<--- %s", __func__);553 kfree(result);554 return -EILSEQ;555}556 557/**558 * befs_nls2utf - Convert NLS string to utf8 encodeing559 * @sb: Superblock560 * @in: Input string buffer in NLS format561 * @in_len: Length of input string in bytes562 * @out: The output string in UTF-8 format563 * @out_len: Length of the output buffer564 *565 * Converts input string @in, which is in the format of the loaded NLS map,566 * into a utf8 string.567 *568 * The destination string @out is allocated by this function and the caller is569 * responsible for freeing it with kfree()570 *571 * On return, *@out_len is the length of @out in bytes.572 *573 * On success, the return value is the number of utf8 characters written to574 * the output buffer @out.575 *576 * On Failure, a negative number coresponding to the error code is returned.577 */578 579static int580befs_nls2utf(struct super_block *sb, const char *in,581 int in_len, char **out, int *out_len)582{583 struct nls_table *nls = BEFS_SB(sb)->nls;584 int i, o;585 wchar_t uni;586 int unilen, utflen;587 char *result;588 /*589 * There are nls characters that will translate to 3-chars-wide UTF-8590 * characters, an additional byte is needed to save the final \0591 * in special cases592 */593 int maxlen = (3 * in_len) + 1;594 595 befs_debug(sb, "---> %s\n", __func__);596 597 if (!nls) {598 befs_error(sb, "%s called with no NLS table loaded.",599 __func__);600 return -EINVAL;601 }602 603 *out = result = kmalloc(maxlen, GFP_NOFS);604 if (!*out) {605 *out_len = 0;606 return -ENOMEM;607 }608 609 for (i = o = 0; i < in_len; i += unilen, o += utflen) {610 611 /* convert from nls to unicode */612 unilen = nls->char2uni(&in[i], in_len - i, &uni);613 if (unilen < 0)614 goto conv_err;615 616 /* convert from unicode to UTF-8 */617 utflen = utf32_to_utf8(uni, &result[o], 3);618 if (utflen <= 0)619 goto conv_err;620 }621 622 result[o] = '\0';623 *out_len = o;624 625 befs_debug(sb, "<--- %s", __func__);626 627 return i;628 629conv_err:630 befs_error(sb, "Name using character set %s contains a character that "631 "cannot be converted to unicode.", nls->charset);632 befs_debug(sb, "<--- %s", __func__);633 kfree(result);634 return -EILSEQ;635}636 637static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino,638 uint32_t generation)639{640 /* No need to handle i_generation */641 return befs_iget(sb, ino);642}643 644/*645 * Map a NFS file handle to a corresponding dentry646 */647static struct dentry *befs_fh_to_dentry(struct super_block *sb,648 struct fid *fid, int fh_len, int fh_type)649{650 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,651 befs_nfs_get_inode);652}653 654/*655 * Find the parent for a file specified by NFS handle656 */657static struct dentry *befs_fh_to_parent(struct super_block *sb,658 struct fid *fid, int fh_len, int fh_type)659{660 return generic_fh_to_parent(sb, fid, fh_len, fh_type,661 befs_nfs_get_inode);662}663 664static struct dentry *befs_get_parent(struct dentry *child)665{666 struct inode *parent;667 struct befs_inode_info *befs_ino = BEFS_I(d_inode(child));668 669 parent = befs_iget(child->d_sb,670 (unsigned long)befs_ino->i_parent.start);671 return d_obtain_alias(parent);672}673 674enum {675 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,676};677 678static const match_table_t befs_tokens = {679 {Opt_uid, "uid=%d"},680 {Opt_gid, "gid=%d"},681 {Opt_charset, "iocharset=%s"},682 {Opt_debug, "debug"},683 {Opt_err, NULL}684};685 686static int687parse_options(char *options, struct befs_mount_options *opts)688{689 char *p;690 substring_t args[MAX_OPT_ARGS];691 int option;692 kuid_t uid;693 kgid_t gid;694 695 /* Initialize options */696 opts->uid = GLOBAL_ROOT_UID;697 opts->gid = GLOBAL_ROOT_GID;698 opts->use_uid = 0;699 opts->use_gid = 0;700 opts->iocharset = NULL;701 opts->debug = 0;702 703 if (!options)704 return 1;705 706 while ((p = strsep(&options, ",")) != NULL) {707 int token;708 709 if (!*p)710 continue;711 712 token = match_token(p, befs_tokens, args);713 switch (token) {714 case Opt_uid:715 if (match_int(&args[0], &option))716 return 0;717 uid = INVALID_UID;718 if (option >= 0)719 uid = make_kuid(current_user_ns(), option);720 if (!uid_valid(uid)) {721 pr_err("Invalid uid %d, "722 "using default\n", option);723 break;724 }725 opts->uid = uid;726 opts->use_uid = 1;727 break;728 case Opt_gid:729 if (match_int(&args[0], &option))730 return 0;731 gid = INVALID_GID;732 if (option >= 0)733 gid = make_kgid(current_user_ns(), option);734 if (!gid_valid(gid)) {735 pr_err("Invalid gid %d, "736 "using default\n", option);737 break;738 }739 opts->gid = gid;740 opts->use_gid = 1;741 break;742 case Opt_charset:743 kfree(opts->iocharset);744 opts->iocharset = match_strdup(&args[0]);745 if (!opts->iocharset) {746 pr_err("allocation failure for "747 "iocharset string\n");748 return 0;749 }750 break;751 case Opt_debug:752 opts->debug = 1;753 break;754 default:755 pr_err("Unrecognized mount option \"%s\" "756 "or missing value\n", p);757 return 0;758 }759 }760 return 1;761}762 763static int befs_show_options(struct seq_file *m, struct dentry *root)764{765 struct befs_sb_info *befs_sb = BEFS_SB(root->d_sb);766 struct befs_mount_options *opts = &befs_sb->mount_opts;767 768 if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))769 seq_printf(m, ",uid=%u",770 from_kuid_munged(&init_user_ns, opts->uid));771 if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))772 seq_printf(m, ",gid=%u",773 from_kgid_munged(&init_user_ns, opts->gid));774 if (opts->iocharset)775 seq_printf(m, ",charset=%s", opts->iocharset);776 if (opts->debug)777 seq_puts(m, ",debug");778 return 0;779}780 781/* This function has the responsibiltiy of getting the782 * filesystem ready for unmounting.783 * Basically, we free everything that we allocated in784 * befs_read_inode785 */786static void787befs_put_super(struct super_block *sb)788{789 kfree(BEFS_SB(sb)->mount_opts.iocharset);790 BEFS_SB(sb)->mount_opts.iocharset = NULL;791 unload_nls(BEFS_SB(sb)->nls);792 kfree(sb->s_fs_info);793 sb->s_fs_info = NULL;794}795 796/* Allocate private field of the superblock, fill it.797 *798 * Finish filling the public superblock fields799 * Make the root directory800 * Load a set of NLS translations if needed.801 */802static int803befs_fill_super(struct super_block *sb, void *data, int silent)804{805 struct buffer_head *bh;806 struct befs_sb_info *befs_sb;807 befs_super_block *disk_sb;808 struct inode *root;809 long ret = -EINVAL;810 const unsigned long sb_block = 0;811 const off_t x86_sb_off = 512;812 int blocksize;813 814 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);815 if (sb->s_fs_info == NULL)816 goto unacquire_none;817 818 befs_sb = BEFS_SB(sb);819 820 if (!parse_options((char *) data, &befs_sb->mount_opts)) {821 if (!silent)822 befs_error(sb, "cannot parse mount options");823 goto unacquire_priv_sbp;824 }825 826 befs_debug(sb, "---> %s", __func__);827 828 if (!sb_rdonly(sb)) {829 befs_warning(sb,830 "No write support. Marking filesystem read-only");831 sb->s_flags |= SB_RDONLY;832 }833 834 /*835 * Set dummy blocksize to read super block.836 * Will be set to real fs blocksize later.837 *838 * Linux 2.4.10 and later refuse to read blocks smaller than839 * the logical block size for the device. But we also need to read at840 * least 1k to get the second 512 bytes of the volume.841 */842 blocksize = sb_min_blocksize(sb, 1024);843 if (!blocksize) {844 if (!silent)845 befs_error(sb, "unable to set blocksize");846 goto unacquire_priv_sbp;847 }848 849 bh = sb_bread(sb, sb_block);850 if (!bh) {851 if (!silent)852 befs_error(sb, "unable to read superblock");853 goto unacquire_priv_sbp;854 }855 856 /* account for offset of super block on x86 */857 disk_sb = (befs_super_block *) bh->b_data;858 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||859 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {860 befs_debug(sb, "Using PPC superblock location");861 } else {862 befs_debug(sb, "Using x86 superblock location");863 disk_sb =864 (befs_super_block *) ((void *) bh->b_data + x86_sb_off);865 }866 867 if ((befs_load_sb(sb, disk_sb) != BEFS_OK) ||868 (befs_check_sb(sb) != BEFS_OK))869 goto unacquire_bh;870 871 befs_dump_super_block(sb, disk_sb);872 873 brelse(bh);874 875 if (befs_sb->num_blocks > ~((sector_t)0)) {876 if (!silent)877 befs_error(sb, "blocks count: %llu is larger than the host can use",878 befs_sb->num_blocks);879 goto unacquire_priv_sbp;880 }881 882 /*883 * set up enough so that it can read an inode884 * Fill in kernel superblock fields from private sb885 */886 sb->s_magic = BEFS_SUPER_MAGIC;887 /* Set real blocksize of fs */888 sb_set_blocksize(sb, (ulong) befs_sb->block_size);889 sb->s_op = &befs_sops;890 sb->s_export_op = &befs_export_operations;891 sb->s_time_min = 0;892 sb->s_time_max = 0xffffffffffffll;893 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));894 if (IS_ERR(root)) {895 ret = PTR_ERR(root);896 goto unacquire_priv_sbp;897 }898 sb->s_root = d_make_root(root);899 if (!sb->s_root) {900 if (!silent)901 befs_error(sb, "get root inode failed");902 goto unacquire_priv_sbp;903 }904 905 /* load nls library */906 if (befs_sb->mount_opts.iocharset) {907 befs_debug(sb, "Loading nls: %s",908 befs_sb->mount_opts.iocharset);909 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);910 if (!befs_sb->nls) {911 befs_warning(sb, "Cannot load nls %s"912 " loading default nls",913 befs_sb->mount_opts.iocharset);914 befs_sb->nls = load_nls_default();915 }916 /* load default nls if none is specified in mount options */917 } else {918 befs_debug(sb, "Loading default nls");919 befs_sb->nls = load_nls_default();920 }921 922 return 0;923 924unacquire_bh:925 brelse(bh);926 927unacquire_priv_sbp:928 kfree(befs_sb->mount_opts.iocharset);929 kfree(sb->s_fs_info);930 sb->s_fs_info = NULL;931 932unacquire_none:933 return ret;934}935 936static int937befs_remount(struct super_block *sb, int *flags, char *data)938{939 sync_filesystem(sb);940 if (!(*flags & SB_RDONLY))941 return -EINVAL;942 return 0;943}944 945static int946befs_statfs(struct dentry *dentry, struct kstatfs *buf)947{948 struct super_block *sb = dentry->d_sb;949 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);950 951 befs_debug(sb, "---> %s", __func__);952 953 buf->f_type = BEFS_SUPER_MAGIC;954 buf->f_bsize = sb->s_blocksize;955 buf->f_blocks = BEFS_SB(sb)->num_blocks;956 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;957 buf->f_bavail = buf->f_bfree;958 buf->f_files = 0; /* UNKNOWN */959 buf->f_ffree = 0; /* UNKNOWN */960 buf->f_fsid = u64_to_fsid(id);961 buf->f_namelen = BEFS_NAME_LEN;962 963 befs_debug(sb, "<--- %s", __func__);964 965 return 0;966}967 968static struct dentry *969befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,970 void *data)971{972 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);973}974 975static struct file_system_type befs_fs_type = {976 .owner = THIS_MODULE,977 .name = "befs",978 .mount = befs_mount,979 .kill_sb = kill_block_super,980 .fs_flags = FS_REQUIRES_DEV,981};982MODULE_ALIAS_FS("befs");983 984static int __init985init_befs_fs(void)986{987 int err;988 989 pr_info("version: %s\n", BEFS_VERSION);990 991 err = befs_init_inodecache();992 if (err)993 goto unacquire_none;994 995 err = register_filesystem(&befs_fs_type);996 if (err)997 goto unacquire_inodecache;998 999 return 0;1000 1001unacquire_inodecache:1002 befs_destroy_inodecache();1003 1004unacquire_none:1005 return err;1006}1007 1008static void __exit1009exit_befs_fs(void)1010{1011 befs_destroy_inodecache();1012 1013 unregister_filesystem(&befs_fs_type);1014}1015 1016/*1017 * Macros that typecheck the init and exit functions,1018 * ensures that they are called at init and cleanup,1019 * and eliminates warnings about unused functions.1020 */1021module_init(init_befs_fs)1022module_exit(exit_befs_fs)1023