| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * linux/fs/befs/linuxvfs.c |
| * |
| * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/fs.h> |
| #include <linux/errno.h> |
| #include <linux/stat.h> |
| #include <linux/nls.h> |
| #include <linux/buffer_head.h> |
| #include <linux/vfs.h> |
| #include <linux/parser.h> |
| #include <linux/namei.h> |
| #include <linux/sched.h> |
| #include <linux/cred.h> |
| #include <linux/exportfs.h> |
| #include <linux/seq_file.h> |
| #include <linux/blkdev.h> |
| |
| #include "befs.h" |
| #include "btree.h" |
| #include "inode.h" |
| #include "datastream.h" |
| #include "super.h" |
| #include "io.h" |
| |
| MODULE_DESCRIPTION("BeOS File System (BeFS) driver"); |
| MODULE_AUTHOR("Will Dyson"); |
| MODULE_LICENSE("GPL"); |
| |
| /* The units the vfs expects inode->i_blocks to be in */ |
| #define VFS_BLOCK_SIZE 512 |
| |
| static int befs_readdir(struct file *, struct dir_context *); |
| static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int); |
| static int befs_read_folio(struct file *file, struct folio *folio); |
| static sector_t befs_bmap(struct address_space *mapping, sector_t block); |
| static struct dentry *befs_lookup(struct inode *, struct dentry *, |
| unsigned int); |
| static struct inode *befs_iget(struct super_block *, unsigned long); |
| static struct inode *befs_alloc_inode(struct super_block *sb); |
| static void befs_free_inode(struct inode *inode); |
| static void befs_destroy_inodecache(void); |
| static int befs_symlink_read_folio(struct file *, struct folio *); |
| static int befs_utf2nls(struct super_block *sb, const char *in, int in_len, |
| char **out, int *out_len); |
| static int befs_nls2utf(struct super_block *sb, const char *in, int in_len, |
| char **out, int *out_len); |
| static void befs_put_super(struct super_block *); |
| static int befs_remount(struct super_block *, int *, char *); |
| static int befs_statfs(struct dentry *, struct kstatfs *); |
| static int befs_show_options(struct seq_file *, struct dentry *); |
| static int parse_options(char *, struct befs_mount_options *); |
| static struct dentry *befs_fh_to_dentry(struct super_block *sb, |
| struct fid *fid, int fh_len, int fh_type); |
| static struct dentry *befs_fh_to_parent(struct super_block *sb, |
| struct fid *fid, int fh_len, int fh_type); |
| static struct dentry *befs_get_parent(struct dentry *child); |
| |
| static const struct super_operations befs_sops = { |
| .alloc_inode = befs_alloc_inode, /* allocate a new inode */ |
| .free_inode = befs_free_inode, /* deallocate an inode */ |
| .put_super = befs_put_super, /* uninit super */ |
| .statfs = befs_statfs, /* statfs */ |
| .remount_fs = befs_remount, |
| .show_options = befs_show_options, |
| }; |
| |
| /* slab cache for befs_inode_info objects */ |
| static struct kmem_cache *befs_inode_cachep; |
| |
| static const struct file_operations befs_dir_operations = { |
| .read = generic_read_dir, |
| .iterate_shared = befs_readdir, |
| .llseek = generic_file_llseek, |
| }; |
| |
| static const struct inode_operations befs_dir_inode_operations = { |
| .lookup = befs_lookup, |
| }; |
| |
| static const struct address_space_operations befs_aops = { |
| .read_folio = befs_read_folio, |
| .bmap = befs_bmap, |
| }; |
| |
| static const struct address_space_operations befs_symlink_aops = { |
| .read_folio = befs_symlink_read_folio, |
| }; |
| |
| static const struct export_operations befs_export_operations = { |
| .encode_fh = generic_encode_ino32_fh, |
| .fh_to_dentry = befs_fh_to_dentry, |
| .fh_to_parent = befs_fh_to_parent, |
| .get_parent = befs_get_parent, |
| }; |
| |
| /* |
| * Called by generic_file_read() to read a folio of data |
| * |
| * In turn, simply calls a generic block read function and |
| * passes it the address of befs_get_block, for mapping file |
| * positions to disk blocks. |
| */ |
| static int befs_read_folio(struct file *file, struct folio *folio) |
| { |
| return block_read_full_folio(folio, befs_get_block); |
| } |
| |
| static sector_t |
| befs_bmap(struct address_space *mapping, sector_t block) |
| { |
| return generic_block_bmap(mapping, block, befs_get_block); |
| } |
| |
| /* |
| * Generic function to map a file position (block) to a |
| * disk offset (passed back in bh_result). |
| * |
| * Used by many higher level functions. |
| * |
| * Calls befs_fblock2brun() in datastream.c to do the real work. |
| */ |
| |
| static int |
| befs_get_block(struct inode *inode, sector_t block, |
| struct buffer_head *bh_result, int create) |
| { |
| struct super_block *sb = inode->i_sb; |
| befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; |
| befs_block_run run = BAD_IADDR; |
| int res; |
| ulong disk_off; |
| |
| befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld", |
| (unsigned long)inode->i_ino, (long)block); |
| if (create) { |
| befs_error(sb, "befs_get_block() was asked to write to " |
| "block %ld in inode %lu", (long)block, |
| (unsigned long)inode->i_ino); |
| return -EPERM; |
| } |
| |
| res = befs_fblock2brun(sb, ds, block, &run); |
| if (res != BEFS_OK) { |
| befs_error(sb, |
| "<--- %s for inode %lu, block %ld ERROR", |
| __func__, (unsigned long)inode->i_ino, |
| (long)block); |
| return -EFBIG; |
| } |
| |
| disk_off = (ulong) iaddr2blockno(sb, &run); |
| |
| map_bh(bh_result, inode->i_sb, disk_off); |
| |
| befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu", |
| __func__, (unsigned long)inode->i_ino, (long)block, |
| (unsigned long)disk_off); |
| |
| return 0; |
| } |
| |
| static struct dentry * |
| befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) |
| { |
| struct inode *inode; |
| struct super_block *sb = dir->i_sb; |
| const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds; |
| befs_off_t offset; |
| int ret; |
| int utfnamelen; |
| char *utfname; |
| const char *name = dentry->d_name.name; |
| |
| befs_debug(sb, "---> %s name %pd inode %ld", __func__, |
| dentry, dir->i_ino); |
| |
| /* Convert to UTF-8 */ |
| if (BEFS_SB(sb)->nls) { |
| ret = |
| befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen); |
| if (ret < 0) { |
| befs_debug(sb, "<--- %s ERROR", __func__); |
| return ERR_PTR(ret); |
| } |
| ret = befs_btree_find(sb, ds, utfname, &offset); |
| kfree(utfname); |
| |
| } else { |
| ret = befs_btree_find(sb, ds, name, &offset); |
| } |
| |
| if (ret == BEFS_BT_NOT_FOUND) { |
| befs_debug(sb, "<--- %s %pd not found", __func__, dentry); |
| inode = NULL; |
| } else if (ret != BEFS_OK || offset == 0) { |
| befs_error(sb, "<--- %s Error", __func__); |
| inode = ERR_PTR(-ENODATA); |
| } else { |
| inode = befs_iget(dir->i_sb, (ino_t) offset); |
| } |
| befs_debug(sb, "<--- %s", __func__); |
| |
| return d_splice_alias(inode, dentry); |
| } |
| |
| static int |
| befs_readdir(struct file *file, struct dir_context *ctx) |
| { |
| struct inode *inode = file_inode(file); |
| struct super_block *sb = inode->i_sb; |
| const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; |
| befs_off_t value; |
| int result; |
| size_t keysize; |
| char keybuf[BEFS_NAME_LEN + 1]; |
| |
| befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld", |
| __func__, file, inode->i_ino, ctx->pos); |
| |
| while (1) { |
| result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1, |
| keybuf, &keysize, &value); |
| |
| if (result == BEFS_ERR) { |
| befs_debug(sb, "<--- %s ERROR", __func__); |
| befs_error(sb, "IO error reading %pD (inode %lu)", |
| file, inode->i_ino); |
| return -EIO; |
| |
| } else if (result == BEFS_BT_END) { |
| befs_debug(sb, "<--- %s END", __func__); |
| return 0; |
| |
| } else if (result == BEFS_BT_EMPTY) { |
| befs_debug(sb, "<--- %s Empty directory", __func__); |
| return 0; |
| } |
| |
| /* Convert to NLS */ |
| if (BEFS_SB(sb)->nls) { |
| char *nlsname; |
| int nlsnamelen; |
| |
| result = |
| befs_utf2nls(sb, keybuf, keysize, &nlsname, |
| &nlsnamelen); |
| if (result < 0) { |
| befs_debug(sb, "<--- %s ERROR", __func__); |
| return result; |
| } |
| if (!dir_emit(ctx, nlsname, nlsnamelen, |
| (ino_t) value, DT_UNKNOWN)) { |
| kfree(nlsname); |
| return 0; |
| } |
| kfree(nlsname); |
| } else { |
| if (!dir_emit(ctx, keybuf, keysize, |
| (ino_t) value, DT_UNKNOWN)) |
| return 0; |
| } |
| ctx->pos++; |
| } |
| } |
| |
| static struct inode * |
| befs_alloc_inode(struct super_block *sb) |
| { |
| struct befs_inode_info *bi; |
| |
| bi = alloc_inode_sb(sb, befs_inode_cachep, GFP_KERNEL); |
| if (!bi) |
| return NULL; |
| return &bi->vfs_inode; |
| } |
| |
| static void befs_free_inode(struct inode *inode) |
| { |
| kmem_cache_free(befs_inode_cachep, BEFS_I(inode)); |
| } |
| |
| static void init_once(void *foo) |
| { |
| struct befs_inode_info *bi = (struct befs_inode_info *) foo; |
| |
| inode_init_once(&bi->vfs_inode); |
| } |
| |
| static struct inode *befs_iget(struct super_block *sb, unsigned long ino) |
| { |
| struct buffer_head *bh; |
| befs_inode *raw_inode; |
| struct befs_sb_info *befs_sb = BEFS_SB(sb); |
| struct befs_inode_info *befs_ino; |
| struct inode *inode; |
| |
| befs_debug(sb, "---> %s inode = %lu", __func__, ino); |
| |
| inode = iget_locked(sb, ino); |
| if (!inode) |
| return ERR_PTR(-ENOMEM); |
| if (!(inode->i_state & I_NEW)) |
| return inode; |
| |
| befs_ino = BEFS_I(inode); |
| |
| /* convert from vfs's inode number to befs's inode number */ |
| befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino); |
| |
| befs_debug(sb, " real inode number [%u, %hu, %hu]", |
| befs_ino->i_inode_num.allocation_group, |
| befs_ino->i_inode_num.start, befs_ino->i_inode_num.len); |
| |
| bh = sb_bread(sb, inode->i_ino); |
| if (!bh) { |
| befs_error(sb, "unable to read inode block - " |
| "inode = %lu", inode->i_ino); |
| goto unacquire_none; |
| } |
| |
| raw_inode = (befs_inode *) bh->b_data; |
| |
| befs_dump_inode(sb, raw_inode); |
| |
| if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) { |
| befs_error(sb, "Bad inode: %lu", inode->i_ino); |
| goto unacquire_bh; |
| } |
| |
| inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode); |
| |
| /* |
| * set uid and gid. But since current BeOS is single user OS, so |
| * you can change by "uid" or "gid" options. |
| */ |
| |
| inode->i_uid = befs_sb->mount_opts.use_uid ? |
| befs_sb->mount_opts.uid : |
| make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid)); |
| inode->i_gid = befs_sb->mount_opts.use_gid ? |
| befs_sb->mount_opts.gid : |
| make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid)); |
| |
| set_nlink(inode, 1); |
| |
| /* |
| * BEFS's time is 64 bits, but current VFS is 32 bits... |
| * BEFS don't have access time. Nor inode change time. VFS |
| * doesn't have creation time. |
| * Also, the lower 16 bits of the last_modified_time and |
| * create_time are just a counter to help ensure uniqueness |
| * for indexing purposes. (PFD, page 54) |
| */ |
| |
| inode_set_mtime(inode, |
| fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16, |
| 0);/* lower 16 bits are not a time */ |
| inode_set_ctime_to_ts(inode, inode_get_mtime(inode)); |
| inode_set_atime_to_ts(inode, inode_get_mtime(inode)); |
| |
| befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num); |
| befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent); |
| befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes); |
| befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags); |
| |
| if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){ |
| inode->i_size = 0; |
| inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE; |
| strscpy(befs_ino->i_data.symlink, raw_inode->data.symlink, |
| BEFS_SYMLINK_LEN); |
| } else { |
| int num_blks; |
| |
| befs_ino->i_data.ds = |
| fsds_to_cpu(sb, &raw_inode->data.datastream); |
| |
| num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds); |
| inode->i_blocks = |
| num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE); |
| inode->i_size = befs_ino->i_data.ds.size; |
| } |
| |
| inode->i_mapping->a_ops = &befs_aops; |
| |
| if (S_ISREG(inode->i_mode)) { |
| inode->i_fop = &generic_ro_fops; |
| } else if (S_ISDIR(inode->i_mode)) { |
| inode->i_op = &befs_dir_inode_operations; |
| inode->i_fop = &befs_dir_operations; |
| } else if (S_ISLNK(inode->i_mode)) { |
| if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { |
| inode->i_op = &page_symlink_inode_operations; |
| inode_nohighmem(inode); |
| inode->i_mapping->a_ops = &befs_symlink_aops; |
| } else { |
| inode->i_link = befs_ino->i_data.symlink; |
| inode->i_op = &simple_symlink_inode_operations; |
| } |
| } else { |
| befs_error(sb, "Inode %lu is not a regular file, " |
| "directory or symlink. THAT IS WRONG! BeFS has no " |
| "on disk special files", inode->i_ino); |
| goto unacquire_bh; |
| } |
| |
| brelse(bh); |
| befs_debug(sb, "<--- %s", __func__); |
| unlock_new_inode(inode); |
| return inode; |
| |
| unacquire_bh: |
| brelse(bh); |
| |
| unacquire_none: |
| iget_failed(inode); |
| befs_debug(sb, "<--- %s - Bad inode", __func__); |
| return ERR_PTR(-EIO); |
| } |
| |
| /* Initialize the inode cache. Called at fs setup. |
| * |
| * Taken from NFS implementation by Al Viro. |
| */ |
| static int __init |
| befs_init_inodecache(void) |
| { |
| befs_inode_cachep = kmem_cache_create_usercopy("befs_inode_cache", |
| sizeof(struct befs_inode_info), 0, |
| (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| |
| SLAB_ACCOUNT), |
| offsetof(struct befs_inode_info, |
| i_data.symlink), |
| sizeof_field(struct befs_inode_info, |
| i_data.symlink), |
| init_once); |
| if (befs_inode_cachep == NULL) |
| return -ENOMEM; |
| |
| return 0; |
| } |
| |
| /* Called at fs teardown. |
| * |
| * Taken from NFS implementation by Al Viro. |
| */ |
| static void |
| befs_destroy_inodecache(void) |
| { |
| /* |
| * Make sure all delayed rcu free inodes are flushed before we |
| * destroy cache. |
| */ |
| rcu_barrier(); |
| kmem_cache_destroy(befs_inode_cachep); |
| } |
| |
| /* |
| * The inode of symbolic link is different to data stream. |
| * The data stream become link name. Unless the LONG_SYMLINK |
| * flag is set. |
| */ |
| static int befs_symlink_read_folio(struct file *unused, struct folio *folio) |
| { |
| struct inode *inode = folio->mapping->host; |
| struct super_block *sb = inode->i_sb; |
| struct befs_inode_info *befs_ino = BEFS_I(inode); |
| befs_data_stream *data = &befs_ino->i_data.ds; |
| befs_off_t len = data->size; |
| char *link = folio_address(folio); |
| |
| if (len == 0 || len > PAGE_SIZE) { |
| befs_error(sb, "Long symlink with illegal length"); |
| goto fail; |
| } |
| befs_debug(sb, "Follow long symlink"); |
| |
| if (befs_read_lsymlink(sb, data, link, len) != len) { |
| befs_error(sb, "Failed to read entire long symlink"); |
| goto fail; |
| } |
| link[len - 1] = '\0'; |
| folio_mark_uptodate(folio); |
| folio_unlock(folio); |
| return 0; |
| fail: |
| folio_set_error(folio); |
| folio_unlock(folio); |
| return -EIO; |
| } |
| |
| /* |
| * UTF-8 to NLS charset convert routine |
| * |
| * Uses uni2char() / char2uni() rather than the nls tables directly |
| */ |
| static int |
| befs_utf2nls(struct super_block *sb, const char *in, |
| int in_len, char **out, int *out_len) |
| { |
| struct nls_table *nls = BEFS_SB(sb)->nls; |
| int i, o; |
| unicode_t uni; |
| int unilen, utflen; |
| char *result; |
| /* The utf8->nls conversion won't make the final nls string bigger |
| * than the utf one, but if the string is pure ascii they'll have the |
| * same width and an extra char is needed to save the additional \0 |
| */ |
| int maxlen = in_len + 1; |
| |
| befs_debug(sb, "---> %s", __func__); |
| |
| if (!nls) { |
| befs_error(sb, "%s called with no NLS table loaded", __func__); |
| return -EINVAL; |
| } |
| |
| *out = result = kmalloc(maxlen, GFP_NOFS); |
| if (!*out) |
| return -ENOMEM; |
| |
| for (i = o = 0; i < in_len; i += utflen, o += unilen) { |
| |
| /* convert from UTF-8 to Unicode */ |
| utflen = utf8_to_utf32(&in[i], in_len - i, &uni); |
| if (utflen < 0) |
| goto conv_err; |
| |
| /* convert from Unicode to nls */ |
| if (uni > MAX_WCHAR_T) |
| goto conv_err; |
| unilen = nls->uni2char(uni, &result[o], in_len - o); |
| if (unilen < 0) |
| goto conv_err; |
| } |
| result[o] = '\0'; |
| *out_len = o; |
| |
| befs_debug(sb, "<--- %s", __func__); |
| |
| return o; |
| |
| conv_err: |
| befs_error(sb, "Name using character set %s contains a character that " |
| "cannot be converted to unicode.", nls->charset); |
| befs_debug(sb, "<--- %s", __func__); |
| kfree(result); |
| return -EILSEQ; |
| } |
| |
| /** |
| * befs_nls2utf - Convert NLS string to utf8 encodeing |
| * @sb: Superblock |
| * @in: Input string buffer in NLS format |
| * @in_len: Length of input string in bytes |
| * @out: The output string in UTF-8 format |
| * @out_len: Length of the output buffer |
| * |
| * Converts input string @in, which is in the format of the loaded NLS map, |
| * into a utf8 string. |
| * |
| * The destination string @out is allocated by this function and the caller is |
| * responsible for freeing it with kfree() |
| * |
| * On return, *@out_len is the length of @out in bytes. |
| * |
| * On success, the return value is the number of utf8 characters written to |
| * the output buffer @out. |
| * |
| * On Failure, a negative number coresponding to the error code is returned. |
| */ |
| |
| static int |
| befs_nls2utf(struct super_block *sb, const char *in, |
| int in_len, char **out, int *out_len) |
| { |
| struct nls_table *nls = BEFS_SB(sb)->nls; |
| int i, o; |
| wchar_t uni; |
| int unilen, utflen; |
| char *result; |
| /* |
| * There are nls characters that will translate to 3-chars-wide UTF-8 |
| * characters, an additional byte is needed to save the final \0 |
| * in special cases |
| */ |
| int maxlen = (3 * in_len) + 1; |
| |
| befs_debug(sb, "---> %s\n", __func__); |
| |
| if (!nls) { |
| befs_error(sb, "%s called with no NLS table loaded.", |
| __func__); |
| return -EINVAL; |
| } |
| |
| *out = result = kmalloc(maxlen, GFP_NOFS); |
| if (!*out) { |
| *out_len = 0; |
| return -ENOMEM; |
| } |
| |
| for (i = o = 0; i < in_len; i += unilen, o += utflen) { |
| |
| /* convert from nls to unicode */ |
| unilen = nls->char2uni(&in[i], in_len - i, &uni); |
| if (unilen < 0) |
| goto conv_err; |
| |
| /* convert from unicode to UTF-8 */ |
| utflen = utf32_to_utf8(uni, &result[o], 3); |
| if (utflen <= 0) |
| goto conv_err; |
| } |
| |
| result[o] = '\0'; |
| *out_len = o; |
| |
| befs_debug(sb, "<--- %s", __func__); |
| |
| return i; |
| |
| conv_err: |
| befs_error(sb, "Name using character set %s contains a character that " |
| "cannot be converted to unicode.", nls->charset); |
| befs_debug(sb, "<--- %s", __func__); |
| kfree(result); |
| return -EILSEQ; |
| } |
| |
| static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino, |
| uint32_t generation) |
| { |
| /* No need to handle i_generation */ |
| return befs_iget(sb, ino); |
| } |
| |
| /* |
| * Map a NFS file handle to a corresponding dentry |
| */ |
| static struct dentry *befs_fh_to_dentry(struct super_block *sb, |
| struct fid *fid, int fh_len, int fh_type) |
| { |
| return generic_fh_to_dentry(sb, fid, fh_len, fh_type, |
| befs_nfs_get_inode); |
| } |
| |
| /* |
| * Find the parent for a file specified by NFS handle |
| */ |
| static struct dentry *befs_fh_to_parent(struct super_block *sb, |
| struct fid *fid, int fh_len, int fh_type) |
| { |
| return generic_fh_to_parent(sb, fid, fh_len, fh_type, |
| befs_nfs_get_inode); |
| } |
| |
| static struct dentry *befs_get_parent(struct dentry *child) |
| { |
| struct inode *parent; |
| struct befs_inode_info *befs_ino = BEFS_I(d_inode(child)); |
| |
| parent = befs_iget(child->d_sb, |
| (unsigned long)befs_ino->i_parent.start); |
| if (IS_ERR(parent)) |
| return ERR_CAST(parent); |
| |
| return d_obtain_alias(parent); |
| } |
| |
| enum { |
| Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err, |
| }; |
| |
| static const match_table_t befs_tokens = { |
| {Opt_uid, "uid=%d"}, |
| {Opt_gid, "gid=%d"}, |
| {Opt_charset, "iocharset=%s"}, |
| {Opt_debug, "debug"}, |
| {Opt_err, NULL} |
| }; |
| |
| static int |
| parse_options(char *options, struct befs_mount_options *opts) |
| { |
| char *p; |
| substring_t args[MAX_OPT_ARGS]; |
| int option; |
| kuid_t uid; |
| kgid_t gid; |
| |
| /* Initialize options */ |
| opts->uid = GLOBAL_ROOT_UID; |
| opts->gid = GLOBAL_ROOT_GID; |
| opts->use_uid = 0; |
| opts->use_gid = 0; |
| opts->iocharset = NULL; |
| opts->debug = 0; |
| |
| if (!options) |
| return 1; |
| |
| while ((p = strsep(&options, ",")) != NULL) { |
| int token; |
| |
| if (!*p) |
| continue; |
| |
| token = match_token(p, befs_tokens, args); |
| switch (token) { |
| case Opt_uid: |
| if (match_int(&args[0], &option)) |
| return 0; |
| uid = INVALID_UID; |
| if (option >= 0) |
| uid = make_kuid(current_user_ns(), option); |
| if (!uid_valid(uid)) { |
| pr_err("Invalid uid %d, " |
| "using default\n", option); |
| break; |
| } |
| opts->uid = uid; |
| opts->use_uid = 1; |
| break; |
| case Opt_gid: |
| if (match_int(&args[0], &option)) |
| return 0; |
| gid = INVALID_GID; |
| if (option >= 0) |
| gid = make_kgid(current_user_ns(), option); |
| if (!gid_valid(gid)) { |
| pr_err("Invalid gid %d, " |
| "using default\n", option); |
| break; |
| } |
| opts->gid = gid; |
| opts->use_gid = 1; |
| break; |
| case Opt_charset: |
| kfree(opts->iocharset); |
| opts->iocharset = match_strdup(&args[0]); |
| if (!opts->iocharset) { |
| pr_err("allocation failure for " |
| "iocharset string\n"); |
| return 0; |
| } |
| break; |
| case Opt_debug: |
| opts->debug = 1; |
| break; |
| default: |
| pr_err("Unrecognized mount option \"%s\" " |
| "or missing value\n", p); |
| return 0; |
| } |
| } |
| return 1; |
| } |
| |
| static int befs_show_options(struct seq_file *m, struct dentry *root) |
| { |
| struct befs_sb_info *befs_sb = BEFS_SB(root->d_sb); |
| struct befs_mount_options *opts = &befs_sb->mount_opts; |
| |
| if (!uid_eq(opts->uid, GLOBAL_ROOT_UID)) |
| seq_printf(m, ",uid=%u", |
| from_kuid_munged(&init_user_ns, opts->uid)); |
| if (!gid_eq(opts->gid, GLOBAL_ROOT_GID)) |
| seq_printf(m, ",gid=%u", |
| from_kgid_munged(&init_user_ns, opts->gid)); |
| if (opts->iocharset) |
| seq_printf(m, ",charset=%s", opts->iocharset); |
| if (opts->debug) |
| seq_puts(m, ",debug"); |
| return 0; |
| } |
| |
| /* This function has the responsibiltiy of getting the |
| * filesystem ready for unmounting. |
| * Basically, we free everything that we allocated in |
| * befs_read_inode |
| */ |
| static void |
| befs_put_super(struct super_block *sb) |
| { |
| kfree(BEFS_SB(sb)->mount_opts.iocharset); |
| BEFS_SB(sb)->mount_opts.iocharset = NULL; |
| unload_nls(BEFS_SB(sb)->nls); |
| kfree(sb->s_fs_info); |
| sb->s_fs_info = NULL; |
| } |
| |
| /* Allocate private field of the superblock, fill it. |
| * |
| * Finish filling the public superblock fields |
| * Make the root directory |
| * Load a set of NLS translations if needed. |
| */ |
| static int |
| befs_fill_super(struct super_block *sb, void *data, int silent) |
| { |
| struct buffer_head *bh; |
| struct befs_sb_info *befs_sb; |
| befs_super_block *disk_sb; |
| struct inode *root; |
| long ret = -EINVAL; |
| const unsigned long sb_block = 0; |
| const off_t x86_sb_off = 512; |
| int blocksize; |
| |
| sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL); |
| if (sb->s_fs_info == NULL) |
| goto unacquire_none; |
| |
| befs_sb = BEFS_SB(sb); |
| |
| if (!parse_options((char *) data, &befs_sb->mount_opts)) { |
| if (!silent) |
| befs_error(sb, "cannot parse mount options"); |
| goto unacquire_priv_sbp; |
| } |
| |
| befs_debug(sb, "---> %s", __func__); |
| |
| if (!sb_rdonly(sb)) { |
| befs_warning(sb, |
| "No write support. Marking filesystem read-only"); |
| sb->s_flags |= SB_RDONLY; |
| } |
| |
| /* |
| * Set dummy blocksize to read super block. |
| * Will be set to real fs blocksize later. |
| * |
| * Linux 2.4.10 and later refuse to read blocks smaller than |
| * the logical block size for the device. But we also need to read at |
| * least 1k to get the second 512 bytes of the volume. |
| */ |
| blocksize = sb_min_blocksize(sb, 1024); |
| if (!blocksize) { |
| if (!silent) |
| befs_error(sb, "unable to set blocksize"); |
| goto unacquire_priv_sbp; |
| } |
| |
| bh = sb_bread(sb, sb_block); |
| if (!bh) { |
| if (!silent) |
| befs_error(sb, "unable to read superblock"); |
| goto unacquire_priv_sbp; |
| } |
| |
| /* account for offset of super block on x86 */ |
| disk_sb = (befs_super_block *) bh->b_data; |
| if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) || |
| (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) { |
| befs_debug(sb, "Using PPC superblock location"); |
| } else { |
| befs_debug(sb, "Using x86 superblock location"); |
| disk_sb = |
| (befs_super_block *) ((void *) bh->b_data + x86_sb_off); |
| } |
| |
| if ((befs_load_sb(sb, disk_sb) != BEFS_OK) || |
| (befs_check_sb(sb) != BEFS_OK)) |
| goto unacquire_bh; |
| |
| befs_dump_super_block(sb, disk_sb); |
| |
| brelse(bh); |
| |
| if (befs_sb->num_blocks > ~((sector_t)0)) { |
| if (!silent) |
| befs_error(sb, "blocks count: %llu is larger than the host can use", |
| befs_sb->num_blocks); |
| goto unacquire_priv_sbp; |
| } |
| |
| /* |
| * set up enough so that it can read an inode |
| * Fill in kernel superblock fields from private sb |
| */ |
| sb->s_magic = BEFS_SUPER_MAGIC; |
| /* Set real blocksize of fs */ |
| sb_set_blocksize(sb, (ulong) befs_sb->block_size); |
| sb->s_op = &befs_sops; |
| sb->s_export_op = &befs_export_operations; |
| sb->s_time_min = 0; |
| sb->s_time_max = 0xffffffffffffll; |
| root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))); |
| if (IS_ERR(root)) { |
| ret = PTR_ERR(root); |
| goto unacquire_priv_sbp; |
| } |
| sb->s_root = d_make_root(root); |
| if (!sb->s_root) { |
| if (!silent) |
| befs_error(sb, "get root inode failed"); |
| goto unacquire_priv_sbp; |
| } |
| |
| /* load nls library */ |
| if (befs_sb->mount_opts.iocharset) { |
| befs_debug(sb, "Loading nls: %s", |
| befs_sb->mount_opts.iocharset); |
| befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset); |
| if (!befs_sb->nls) { |
| befs_warning(sb, "Cannot load nls %s" |
| " loading default nls", |
| befs_sb->mount_opts.iocharset); |
| befs_sb->nls = load_nls_default(); |
| } |
| /* load default nls if none is specified in mount options */ |
| } else { |
| befs_debug(sb, "Loading default nls"); |
| befs_sb->nls = load_nls_default(); |
| } |
| |
| return 0; |
| |
| unacquire_bh: |
| brelse(bh); |
| |
| unacquire_priv_sbp: |
| kfree(befs_sb->mount_opts.iocharset); |
| kfree(sb->s_fs_info); |
| sb->s_fs_info = NULL; |
| |
| unacquire_none: |
| return ret; |
| } |
| |
| static int |
| befs_remount(struct super_block *sb, int *flags, char *data) |
| { |
| sync_filesystem(sb); |
| if (!(*flags & SB_RDONLY)) |
| return -EINVAL; |
| return 0; |
| } |
| |
| static int |
| befs_statfs(struct dentry *dentry, struct kstatfs *buf) |
| { |
| struct super_block *sb = dentry->d_sb; |
| u64 id = huge_encode_dev(sb->s_bdev->bd_dev); |
| |
| befs_debug(sb, "---> %s", __func__); |
| |
| buf->f_type = BEFS_SUPER_MAGIC; |
| buf->f_bsize = sb->s_blocksize; |
| buf->f_blocks = BEFS_SB(sb)->num_blocks; |
| buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks; |
| buf->f_bavail = buf->f_bfree; |
| buf->f_files = 0; /* UNKNOWN */ |
| buf->f_ffree = 0; /* UNKNOWN */ |
| buf->f_fsid = u64_to_fsid(id); |
| buf->f_namelen = BEFS_NAME_LEN; |
| |
| befs_debug(sb, "<--- %s", __func__); |
| |
| return 0; |
| } |
| |
| static struct dentry * |
| befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, |
| void *data) |
| { |
| return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super); |
| } |
| |
| static struct file_system_type befs_fs_type = { |
| .owner = THIS_MODULE, |
| .name = "befs", |
| .mount = befs_mount, |
| .kill_sb = kill_block_super, |
| .fs_flags = FS_REQUIRES_DEV, |
| }; |
| MODULE_ALIAS_FS("befs"); |
| |
| static int __init |
| init_befs_fs(void) |
| { |
| int err; |
| |
| pr_info("version: %s\n", BEFS_VERSION); |
| |
| err = befs_init_inodecache(); |
| if (err) |
| goto unacquire_none; |
| |
| err = register_filesystem(&befs_fs_type); |
| if (err) |
| goto unacquire_inodecache; |
| |
| return 0; |
| |
| unacquire_inodecache: |
| befs_destroy_inodecache(); |
| |
| unacquire_none: |
| return err; |
| } |
| |
| static void __exit |
| exit_befs_fs(void) |
| { |
| befs_destroy_inodecache(); |
| |
| unregister_filesystem(&befs_fs_type); |
| } |
| |
| /* |
| * Macros that typecheck the init and exit functions, |
| * ensures that they are called at init and cleanup, |
| * and eliminates warnings about unused functions. |
| */ |
| module_init(init_befs_fs) |
| module_exit(exit_befs_fs) |