diff options
Diffstat (limited to 'fs/msdos/namei.c')
-rw-r--r-- | fs/msdos/namei.c | 702 |
1 files changed, 0 insertions, 702 deletions
diff --git a/fs/msdos/namei.c b/fs/msdos/namei.c deleted file mode 100644 index e844b9809d2..00000000000 --- a/fs/msdos/namei.c +++ /dev/null @@ -1,702 +0,0 @@ -/* - * linux/fs/msdos/namei.c - * - * Written 1992,1993 by Werner Almesberger - * Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu> - * Rewritten for constant inumbers 1999 by Al Viro - */ - -#include <linux/module.h> -#include <linux/time.h> -#include <linux/buffer_head.h> -#include <linux/msdos_fs.h> -#include <linux/smp_lock.h> - -/* Characters that are undesirable in an MS-DOS file name */ -static unsigned char bad_chars[] = "*?<>|\""; -static unsigned char bad_if_strict[] = "+=,; "; - -/***** Formats an MS-DOS file name. Rejects invalid names. */ -static int msdos_format_name(const unsigned char *name, int len, - unsigned char *res, struct fat_mount_options *opts) - /* - * name is the proposed name, len is its length, res is - * the resulting name, opts->name_check is either (r)elaxed, - * (n)ormal or (s)trict, opts->dotsOK allows dots at the - * beginning of name (for hidden files) - */ -{ - unsigned char *walk; - unsigned char c; - int space; - - if (name[0] == '.') { /* dotfile because . and .. already done */ - if (opts->dotsOK) { - /* Get rid of dot - test for it elsewhere */ - name++; - len--; - } else - return -EINVAL; - } - /* - * disallow names that _really_ start with a dot - */ - space = 1; - c = 0; - for (walk = res; len && walk - res < 8; walk++) { - c = *name++; - len--; - if (opts->name_check != 'r' && strchr(bad_chars, c)) - return -EINVAL; - if (opts->name_check == 's' && strchr(bad_if_strict, c)) - return -EINVAL; - if (c >= 'A' && c <= 'Z' && opts->name_check == 's') - return -EINVAL; - if (c < ' ' || c == ':' || c == '\\') - return -EINVAL; - /* - * 0xE5 is legal as a first character, but we must substitute - * 0x05 because 0xE5 marks deleted files. Yes, DOS really - * does this. - * It seems that Microsoft hacked DOS to support non-US - * characters after the 0xE5 character was already in use to - * mark deleted files. - */ - if ((res == walk) && (c == 0xE5)) - c = 0x05; - if (c == '.') - break; - space = (c == ' '); - *walk = (!opts->nocase && c >= 'a' && c <= 'z') ? c - 32 : c; - } - if (space) - return -EINVAL; - if (opts->name_check == 's' && len && c != '.') { - c = *name++; - len--; - if (c != '.') - return -EINVAL; - } - while (c != '.' && len--) - c = *name++; - if (c == '.') { - while (walk - res < 8) - *walk++ = ' '; - while (len > 0 && walk - res < MSDOS_NAME) { - c = *name++; - len--; - if (opts->name_check != 'r' && strchr(bad_chars, c)) - return -EINVAL; - if (opts->name_check == 's' && - strchr(bad_if_strict, c)) - return -EINVAL; - if (c < ' ' || c == ':' || c == '\\') - return -EINVAL; - if (c == '.') { - if (opts->name_check == 's') - return -EINVAL; - break; - } - if (c >= 'A' && c <= 'Z' && opts->name_check == 's') - return -EINVAL; - space = c == ' '; - if (!opts->nocase && c >= 'a' && c <= 'z') - *walk++ = c - 32; - else - *walk++ = c; - } - if (space) - return -EINVAL; - if (opts->name_check == 's' && len) - return -EINVAL; - } - while (walk - res < MSDOS_NAME) - *walk++ = ' '; - - return 0; -} - -/***** Locates a directory entry. Uses unformatted name. */ -static int msdos_find(struct inode *dir, const unsigned char *name, int len, - struct fat_slot_info *sinfo) -{ - struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb); - unsigned char msdos_name[MSDOS_NAME]; - int err; - - err = msdos_format_name(name, len, msdos_name, &sbi->options); - if (err) - return -ENOENT; - - err = fat_scan(dir, msdos_name, sinfo); - if (!err && sbi->options.dotsOK) { - if (name[0] == '.') { - if (!(sinfo->de->attr & ATTR_HIDDEN)) - err = -ENOENT; - } else { - if (sinfo->de->attr & ATTR_HIDDEN) - err = -ENOENT; - } - if (err) - brelse(sinfo->bh); - } - return err; -} - -/* - * Compute the hash for the msdos name corresponding to the dentry. - * Note: if the name is invalid, we leave the hash code unchanged so - * that the existing dentry can be used. The msdos fs routines will - * return ENOENT or EINVAL as appropriate. - */ -static int msdos_hash(struct dentry *dentry, struct qstr *qstr) -{ - struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options; - unsigned char msdos_name[MSDOS_NAME]; - int error; - - error = msdos_format_name(qstr->name, qstr->len, msdos_name, options); - if (!error) - qstr->hash = full_name_hash(msdos_name, MSDOS_NAME); - return 0; -} - -/* - * Compare two msdos names. If either of the names are invalid, - * we fall back to doing the standard name comparison. - */ -static int msdos_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b) -{ - struct fat_mount_options *options = &MSDOS_SB(dentry->d_sb)->options; - unsigned char a_msdos_name[MSDOS_NAME], b_msdos_name[MSDOS_NAME]; - int error; - - error = msdos_format_name(a->name, a->len, a_msdos_name, options); - if (error) - goto old_compare; - error = msdos_format_name(b->name, b->len, b_msdos_name, options); - if (error) - goto old_compare; - error = memcmp(a_msdos_name, b_msdos_name, MSDOS_NAME); -out: - return error; - -old_compare: - error = 1; - if (a->len == b->len) - error = memcmp(a->name, b->name, a->len); - goto out; -} - -static struct dentry_operations msdos_dentry_operations = { - .d_hash = msdos_hash, - .d_compare = msdos_cmp, -}; - -/* - * AV. Wrappers for FAT sb operations. Is it wise? - */ - -/***** Get inode using directory and name */ -static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry, - struct nameidata *nd) -{ - struct super_block *sb = dir->i_sb; - struct fat_slot_info sinfo; - struct inode *inode = NULL; - int res; - - dentry->d_op = &msdos_dentry_operations; - - lock_super(sb); - res = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo); - if (res == -ENOENT) - goto add; - if (res < 0) - goto out; - inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); - brelse(sinfo.bh); - if (IS_ERR(inode)) { - res = PTR_ERR(inode); - goto out; - } -add: - res = 0; - dentry = d_splice_alias(inode, dentry); - if (dentry) - dentry->d_op = &msdos_dentry_operations; -out: - unlock_super(sb); - if (!res) - return dentry; - return ERR_PTR(res); -} - -/***** Creates a directory entry (name is already formatted). */ -static int msdos_add_entry(struct inode *dir, const unsigned char *name, - int is_dir, int is_hid, int cluster, - struct timespec *ts, struct fat_slot_info *sinfo) -{ - struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb); - struct msdos_dir_entry de; - __le16 time, date; - int err; - - memcpy(de.name, name, MSDOS_NAME); - de.attr = is_dir ? ATTR_DIR : ATTR_ARCH; - if (is_hid) - de.attr |= ATTR_HIDDEN; - de.lcase = 0; - fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc); - de.cdate = de.adate = 0; - de.ctime = 0; - de.ctime_cs = 0; - de.time = time; - de.date = date; - de.start = cpu_to_le16(cluster); - de.starthi = cpu_to_le16(cluster >> 16); - de.size = 0; - - err = fat_add_entries(dir, &de, 1, sinfo); - if (err) - return err; - - dir->i_ctime = dir->i_mtime = *ts; - if (IS_DIRSYNC(dir)) - (void)fat_sync_inode(dir); - else - mark_inode_dirty(dir); - - return 0; -} - -/***** Create a file */ -static int msdos_create(struct inode *dir, struct dentry *dentry, int mode, - struct nameidata *nd) -{ - struct super_block *sb = dir->i_sb; - struct inode *inode = NULL; - struct fat_slot_info sinfo; - struct timespec ts; - unsigned char msdos_name[MSDOS_NAME]; - int err, is_hid; - - lock_super(sb); - - err = msdos_format_name(dentry->d_name.name, dentry->d_name.len, - msdos_name, &MSDOS_SB(sb)->options); - if (err) - goto out; - is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.'); - /* Have to do it due to foo vs. .foo conflicts */ - if (!fat_scan(dir, msdos_name, &sinfo)) { - brelse(sinfo.bh); - err = -EINVAL; - goto out; - } - - ts = CURRENT_TIME_SEC; - err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo); - if (err) - goto out; - inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); - brelse(sinfo.bh); - if (IS_ERR(inode)) { - err = PTR_ERR(inode); - goto out; - } - inode->i_mtime = inode->i_atime = inode->i_ctime = ts; - /* timestamp is already written, so mark_inode_dirty() is unneeded. */ - - d_instantiate(dentry, inode); -out: - unlock_super(sb); - if (!err) - err = fat_flush_inodes(sb, dir, inode); - return err; -} - -/***** Remove a directory */ -static int msdos_rmdir(struct inode *dir, struct dentry *dentry) -{ - struct super_block *sb = dir->i_sb; - struct inode *inode = dentry->d_inode; - struct fat_slot_info sinfo; - int err; - - lock_super(sb); - /* - * Check whether the directory is not in use, then check - * whether it is empty. - */ - err = fat_dir_empty(inode); - if (err) - goto out; - err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo); - if (err) - goto out; - - err = fat_remove_entries(dir, &sinfo); /* and releases bh */ - if (err) - goto out; - drop_nlink(dir); - - clear_nlink(inode); - inode->i_ctime = CURRENT_TIME_SEC; - fat_detach(inode); -out: - unlock_super(sb); - if (!err) - err = fat_flush_inodes(sb, dir, inode); - - return err; -} - -/***** Make a directory */ -static int msdos_mkdir(struct inode *dir, struct dentry *dentry, int mode) -{ - struct super_block *sb = dir->i_sb; - struct fat_slot_info sinfo; - struct inode *inode; - unsigned char msdos_name[MSDOS_NAME]; - struct timespec ts; - int err, is_hid, cluster; - - lock_super(sb); - - err = msdos_format_name(dentry->d_name.name, dentry->d_name.len, - msdos_name, &MSDOS_SB(sb)->options); - if (err) - goto out; - is_hid = (dentry->d_name.name[0] == '.') && (msdos_name[0] != '.'); - /* foo vs .foo situation */ - if (!fat_scan(dir, msdos_name, &sinfo)) { - brelse(sinfo.bh); - err = -EINVAL; - goto out; - } - - ts = CURRENT_TIME_SEC; - cluster = fat_alloc_new_dir(dir, &ts); - if (cluster < 0) { - err = cluster; - goto out; - } - err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo); - if (err) - goto out_free; - inc_nlink(dir); - - inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); - brelse(sinfo.bh); - if (IS_ERR(inode)) { - err = PTR_ERR(inode); - /* the directory was completed, just return a error */ - goto out; - } - inode->i_nlink = 2; - inode->i_mtime = inode->i_atime = inode->i_ctime = ts; - /* timestamp is already written, so mark_inode_dirty() is unneeded. */ - - d_instantiate(dentry, inode); - - unlock_super(sb); - fat_flush_inodes(sb, dir, inode); - return 0; - -out_free: - fat_free_clusters(dir, cluster); -out: - unlock_super(sb); - return err; -} - -/***** Unlink a file */ -static int msdos_unlink(struct inode *dir, struct dentry *dentry) -{ - struct inode *inode = dentry->d_inode; - struct super_block *sb= inode->i_sb; - struct fat_slot_info sinfo; - int err; - - lock_super(sb); - err = msdos_find(dir, dentry->d_name.name, dentry->d_name.len, &sinfo); - if (err) - goto out; - - err = fat_remove_entries(dir, &sinfo); /* and releases bh */ - if (err) - goto out; - clear_nlink(inode); - inode->i_ctime = CURRENT_TIME_SEC; - fat_detach(inode); -out: - unlock_super(sb); - if (!err) - err = fat_flush_inodes(sb, dir, inode); - - return err; -} - -static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name, - struct dentry *old_dentry, - struct inode *new_dir, unsigned char *new_name, - struct dentry *new_dentry, int is_hid) -{ - struct buffer_head *dotdot_bh; - struct msdos_dir_entry *dotdot_de; - struct inode *old_inode, *new_inode; - struct fat_slot_info old_sinfo, sinfo; - struct timespec ts; - loff_t dotdot_i_pos, new_i_pos; - int err, old_attrs, is_dir, update_dotdot, corrupt = 0; - - old_sinfo.bh = sinfo.bh = dotdot_bh = NULL; - old_inode = old_dentry->d_inode; - new_inode = new_dentry->d_inode; - - err = fat_scan(old_dir, old_name, &old_sinfo); - if (err) { - err = -EIO; - goto out; - } - - is_dir = S_ISDIR(old_inode->i_mode); - update_dotdot = (is_dir && old_dir != new_dir); - if (update_dotdot) { - if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de, - &dotdot_i_pos) < 0) { - err = -EIO; - goto out; - } - } - - old_attrs = MSDOS_I(old_inode)->i_attrs; - err = fat_scan(new_dir, new_name, &sinfo); - if (!err) { - if (!new_inode) { - /* "foo" -> ".foo" case. just change the ATTR_HIDDEN */ - if (sinfo.de != old_sinfo.de) { - err = -EINVAL; - goto out; - } - if (is_hid) - MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN; - else - MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN; - if (IS_DIRSYNC(old_dir)) { - err = fat_sync_inode(old_inode); - if (err) { - MSDOS_I(old_inode)->i_attrs = old_attrs; - goto out; - } - } else - mark_inode_dirty(old_inode); - - old_dir->i_version++; - old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; - if (IS_DIRSYNC(old_dir)) - (void)fat_sync_inode(old_dir); - else - mark_inode_dirty(old_dir); - goto out; - } - } - - ts = CURRENT_TIME_SEC; - if (new_inode) { - if (err) - goto out; - if (is_dir) { - err = fat_dir_empty(new_inode); - if (err) - goto out; - } - new_i_pos = MSDOS_I(new_inode)->i_pos; - fat_detach(new_inode); - } else { - err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0, - &ts, &sinfo); - if (err) - goto out; - new_i_pos = sinfo.i_pos; - } - new_dir->i_version++; - - fat_detach(old_inode); - fat_attach(old_inode, new_i_pos); - if (is_hid) - MSDOS_I(old_inode)->i_attrs |= ATTR_HIDDEN; - else - MSDOS_I(old_inode)->i_attrs &= ~ATTR_HIDDEN; - if (IS_DIRSYNC(new_dir)) { - err = fat_sync_inode(old_inode); - if (err) - goto error_inode; - } else - mark_inode_dirty(old_inode); - - if (update_dotdot) { - int start = MSDOS_I(new_dir)->i_logstart; - dotdot_de->start = cpu_to_le16(start); - dotdot_de->starthi = cpu_to_le16(start >> 16); - mark_buffer_dirty(dotdot_bh); - if (IS_DIRSYNC(new_dir)) { - err = sync_dirty_buffer(dotdot_bh); - if (err) - goto error_dotdot; - } - drop_nlink(old_dir); - if (!new_inode) - inc_nlink(new_dir); - } - - err = fat_remove_entries(old_dir, &old_sinfo); /* and releases bh */ - old_sinfo.bh = NULL; - if (err) - goto error_dotdot; - old_dir->i_version++; - old_dir->i_ctime = old_dir->i_mtime = ts; - if (IS_DIRSYNC(old_dir)) - (void)fat_sync_inode(old_dir); - else - mark_inode_dirty(old_dir); - - if (new_inode) { - drop_nlink(new_inode); - if (is_dir) - drop_nlink(new_inode); - new_inode->i_ctime = ts; - } -out: - brelse(sinfo.bh); - brelse(dotdot_bh); - brelse(old_sinfo.bh); - return err; - -error_dotdot: - /* data cluster is shared, serious corruption */ - corrupt = 1; - - if (update_dotdot) { - int start = MSDOS_I(old_dir)->i_logstart; - dotdot_de->start = cpu_to_le16(start); - dotdot_de->starthi = cpu_to_le16(start >> 16); - mark_buffer_dirty(dotdot_bh); - corrupt |= sync_dirty_buffer(dotdot_bh); - } -error_inode: - fat_detach(old_inode); - fat_attach(old_inode, old_sinfo.i_pos); - MSDOS_I(old_inode)->i_attrs = old_attrs; - if (new_inode) { - fat_attach(new_inode, new_i_pos); - if (corrupt) - corrupt |= fat_sync_inode(new_inode); - } else { - /* - * If new entry was not sharing the data cluster, it - * shouldn't be serious corruption. - */ - int err2 = fat_remove_entries(new_dir, &sinfo); - if (corrupt) - corrupt |= err2; - sinfo.bh = NULL; - } - if (corrupt < 0) { - fat_fs_panic(new_dir->i_sb, - "%s: Filesystem corrupted (i_pos %lld)", - __func__, sinfo.i_pos); - } - goto out; -} - -/***** Rename, a wrapper for rename_same_dir & rename_diff_dir */ -static int msdos_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) -{ - struct super_block *sb = old_dir->i_sb; - unsigned char old_msdos_name[MSDOS_NAME], new_msdos_name[MSDOS_NAME]; - int err, is_hid; - - lock_super(sb); - - err = msdos_format_name(old_dentry->d_name.name, - old_dentry->d_name.len, old_msdos_name, - &MSDOS_SB(old_dir->i_sb)->options); - if (err) - goto out; - err = msdos_format_name(new_dentry->d_name.name, - new_dentry->d_name.len, new_msdos_name, - &MSDOS_SB(new_dir->i_sb)->options); - if (err) - goto out; - - is_hid = - (new_dentry->d_name.name[0] == '.') && (new_msdos_name[0] != '.'); - - err = do_msdos_rename(old_dir, old_msdos_name, old_dentry, - new_dir, new_msdos_name, new_dentry, is_hid); -out: - unlock_super(sb); - if (!err) - err = fat_flush_inodes(sb, old_dir, new_dir); - return err; -} - -static const struct inode_operations msdos_dir_inode_operations = { - .create = msdos_create, - .lookup = msdos_lookup, - .unlink = msdos_unlink, - .mkdir = msdos_mkdir, - .rmdir = msdos_rmdir, - .rename = msdos_rename, - .setattr = fat_setattr, - .getattr = fat_getattr, -}; - -static int msdos_fill_super(struct super_block *sb, void *data, int silent) -{ - int res; - - res = fat_fill_super(sb, data, silent, &msdos_dir_inode_operations, 0); - if (res) - return res; - - sb->s_flags |= MS_NOATIME; - sb->s_root->d_op = &msdos_dentry_operations; - return 0; -} - -static int msdos_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *data, struct vfsmount *mnt) -{ - return get_sb_bdev(fs_type, flags, dev_name, data, msdos_fill_super, - mnt); -} - -static struct file_system_type msdos_fs_type = { - .owner = THIS_MODULE, - .name = "msdos", - .get_sb = msdos_get_sb, - .kill_sb = kill_block_super, - .fs_flags = FS_REQUIRES_DEV, -}; - -static int __init init_msdos_fs(void) -{ - return register_filesystem(&msdos_fs_type); -} - -static void __exit exit_msdos_fs(void) -{ - unregister_filesystem(&msdos_fs_type); -} - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Werner Almesberger"); -MODULE_DESCRIPTION("MS-DOS filesystem support"); - -module_init(init_msdos_fs) -module_exit(exit_msdos_fs) |