From 990e194e69009028e029b7d25da68c38241ec4f0 Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Thu, 6 Nov 2008 12:53:45 -0800 Subject: fat: move fs/vfat/* and fs/msdos/* to fs/fat This just moves those files, but change link order from MSDOS, VFAT to VFAT, MSDOS. Signed-off-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/Makefile | 6 +- fs/fat/namei_msdos.c | 702 +++++++++++++++++++++++++++++++++ fs/fat/namei_vfat.c | 1055 ++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1762 insertions(+), 1 deletion(-) create mode 100644 fs/fat/namei_msdos.c create mode 100644 fs/fat/namei_vfat.c (limited to 'fs/fat') diff --git a/fs/fat/Makefile b/fs/fat/Makefile index bfb5f06cf2c8..e06190322c1c 100644 --- a/fs/fat/Makefile +++ b/fs/fat/Makefile @@ -3,5 +3,9 @@ # obj-$(CONFIG_FAT_FS) += fat.o +obj-$(CONFIG_VFAT_FS) += vfat.o +obj-$(CONFIG_MSDOS_FS) += msdos.o -fat-objs := cache.o dir.o fatent.o file.o inode.o misc.o +fat-y := cache.o dir.o fatent.o file.o inode.o misc.o +vfat-y := namei_vfat.o +msdos-y := namei_msdos.o diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c new file mode 100644 index 000000000000..e844b9809d27 --- /dev/null +++ b/fs/fat/namei_msdos.c @@ -0,0 +1,702 @@ +/* + * linux/fs/msdos/namei.c + * + * Written 1992,1993 by Werner Almesberger + * Hidden files 1995 by Albert Cahalan + * Rewritten for constant inumbers 1999 by Al Viro + */ + +#include +#include +#include +#include +#include + +/* 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) diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c new file mode 100644 index 000000000000..155c10b4adbd --- /dev/null +++ b/fs/fat/namei_vfat.c @@ -0,0 +1,1055 @@ +/* + * linux/fs/vfat/namei.c + * + * Written 1992,1993 by Werner Almesberger + * + * Windows95/Windows NT compatible extended MSDOS filesystem + * by Gordon Chaffee Copyright (C) 1995. Send bug reports for the + * VFAT filesystem to . Specify + * what file operation caused you trouble and if you can duplicate + * the problem, send a script that demonstrates it. + * + * Short name translation 1999, 2001 by Wolfram Pienkoss + * + * Support Multibyte characters and cleanup by + * OGAWA Hirofumi + */ + +#include + +#include +#include +#include +#include +#include +#include +#include + +static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd) +{ + int ret = 1; + + if (!dentry->d_inode && + nd && !(nd->flags & LOOKUP_CONTINUE) && (nd->flags & LOOKUP_CREATE)) + /* + * negative dentry is dropped, in order to make sure + * to use the name which a user desires if this is + * create path. + */ + ret = 0; + else { + spin_lock(&dentry->d_lock); + if (dentry->d_time != dentry->d_parent->d_inode->i_version) + ret = 0; + spin_unlock(&dentry->d_lock); + } + return ret; +} + +/* returns the length of a struct qstr, ignoring trailing dots */ +static unsigned int vfat_striptail_len(struct qstr *qstr) +{ + unsigned int len = qstr->len; + + while (len && qstr->name[len - 1] == '.') + len--; + return len; +} + +/* + * Compute the hash for the vfat 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 vfat fs routines will + * return ENOENT or EINVAL as appropriate. + */ +static int vfat_hash(struct dentry *dentry, struct qstr *qstr) +{ + qstr->hash = full_name_hash(qstr->name, vfat_striptail_len(qstr)); + return 0; +} + +/* + * Compute the hash for the vfat 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 vfat fs routines will + * return ENOENT or EINVAL as appropriate. + */ +static int vfat_hashi(struct dentry *dentry, struct qstr *qstr) +{ + struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io; + const unsigned char *name; + unsigned int len; + unsigned long hash; + + name = qstr->name; + len = vfat_striptail_len(qstr); + + hash = init_name_hash(); + while (len--) + hash = partial_name_hash(nls_tolower(t, *name++), hash); + qstr->hash = end_name_hash(hash); + + return 0; +} + +/* + * Case insensitive compare of two vfat names. + */ +static int vfat_cmpi(struct dentry *dentry, struct qstr *a, struct qstr *b) +{ + struct nls_table *t = MSDOS_SB(dentry->d_inode->i_sb)->nls_io; + unsigned int alen, blen; + + /* A filename cannot end in '.' or we treat it like it has none */ + alen = vfat_striptail_len(a); + blen = vfat_striptail_len(b); + if (alen == blen) { + if (nls_strnicmp(t, a->name, b->name, alen) == 0) + return 0; + } + return 1; +} + +/* + * Case sensitive compare of two vfat names. + */ +static int vfat_cmp(struct dentry *dentry, struct qstr *a, struct qstr *b) +{ + unsigned int alen, blen; + + /* A filename cannot end in '.' or we treat it like it has none */ + alen = vfat_striptail_len(a); + blen = vfat_striptail_len(b); + if (alen == blen) { + if (strncmp(a->name, b->name, alen) == 0) + return 0; + } + return 1; +} + +static struct dentry_operations vfat_dentry_ops[4] = { + { + .d_hash = vfat_hashi, + .d_compare = vfat_cmpi, + }, + { + .d_revalidate = vfat_revalidate, + .d_hash = vfat_hashi, + .d_compare = vfat_cmpi, + }, + { + .d_hash = vfat_hash, + .d_compare = vfat_cmp, + }, + { + .d_revalidate = vfat_revalidate, + .d_hash = vfat_hash, + .d_compare = vfat_cmp, + } +}; + +/* Characters that are undesirable in an MS-DOS file name */ + +static inline wchar_t vfat_bad_char(wchar_t w) +{ + return (w < 0x0020) + || (w == '*') || (w == '?') || (w == '<') || (w == '>') + || (w == '|') || (w == '"') || (w == ':') || (w == '/') + || (w == '\\'); +} + +static inline wchar_t vfat_replace_char(wchar_t w) +{ + return (w == '[') || (w == ']') || (w == ';') || (w == ',') + || (w == '+') || (w == '='); +} + +static wchar_t vfat_skip_char(wchar_t w) +{ + return (w == '.') || (w == ' '); +} + +static inline int vfat_is_used_badchars(const wchar_t *s, int len) +{ + int i; + + for (i = 0; i < len; i++) + if (vfat_bad_char(s[i])) + return -EINVAL; + + if (s[i - 1] == ' ') /* last character cannot be space */ + return -EINVAL; + + return 0; +} + +static int vfat_find_form(struct inode *dir, unsigned char *name) +{ + struct fat_slot_info sinfo; + int err = fat_scan(dir, name, &sinfo); + if (err) + return -ENOENT; + brelse(sinfo.bh); + return 0; +} + +/* + * 1) Valid characters for the 8.3 format alias are any combination of + * letters, uppercase alphabets, digits, any of the + * following special characters: + * $ % ' ` - @ { } ~ ! # ( ) & _ ^ + * In this case Longfilename is not stored in disk. + * + * WinNT's Extension: + * File name and extension name is contain uppercase/lowercase + * only. And it is expressed by CASE_LOWER_BASE and CASE_LOWER_EXT. + * + * 2) File name is 8.3 format, but it contain the uppercase and + * lowercase char, muliti bytes char, etc. In this case numtail is not + * added, but Longfilename is stored. + * + * 3) When the one except for the above, or the following special + * character are contained: + * . [ ] ; , + = + * numtail is added, and Longfilename must be stored in disk . + */ +struct shortname_info { + unsigned char lower:1, + upper:1, + valid:1; +}; +#define INIT_SHORTNAME_INFO(x) do { \ + (x)->lower = 1; \ + (x)->upper = 1; \ + (x)->valid = 1; \ +} while (0) + +static inline int to_shortname_char(struct nls_table *nls, + unsigned char *buf, int buf_size, + wchar_t *src, struct shortname_info *info) +{ + int len; + + if (vfat_skip_char(*src)) { + info->valid = 0; + return 0; + } + if (vfat_replace_char(*src)) { + info->valid = 0; + buf[0] = '_'; + return 1; + } + + len = nls->uni2char(*src, buf, buf_size); + if (len <= 0) { + info->valid = 0; + buf[0] = '_'; + len = 1; + } else if (len == 1) { + unsigned char prev = buf[0]; + + if (buf[0] >= 0x7F) { + info->lower = 0; + info->upper = 0; + } + + buf[0] = nls_toupper(nls, buf[0]); + if (isalpha(buf[0])) { + if (buf[0] == prev) + info->lower = 0; + else + info->upper = 0; + } + } else { + info->lower = 0; + info->upper = 0; + } + + return len; +} + +/* + * Given a valid longname, create a unique shortname. Make sure the + * shortname does not exist + * Returns negative number on error, 0 for a normal + * return, and 1 for valid shortname + */ +static int vfat_create_shortname(struct inode *dir, struct nls_table *nls, + wchar_t *uname, int ulen, + unsigned char *name_res, unsigned char *lcase) +{ + struct fat_mount_options *opts = &MSDOS_SB(dir->i_sb)->options; + wchar_t *ip, *ext_start, *end, *name_start; + unsigned char base[9], ext[4], buf[8], *p; + unsigned char charbuf[NLS_MAX_CHARSET_SIZE]; + int chl, chi; + int sz = 0, extlen, baselen, i, numtail_baselen, numtail2_baselen; + int is_shortname; + struct shortname_info base_info, ext_info; + + is_shortname = 1; + INIT_SHORTNAME_INFO(&base_info); + INIT_SHORTNAME_INFO(&ext_info); + + /* Now, we need to create a shortname from the long name */ + ext_start = end = &uname[ulen]; + while (--ext_start >= uname) { + if (*ext_start == 0x002E) { /* is `.' */ + if (ext_start == end - 1) { + sz = ulen; + ext_start = NULL; + } + break; + } + } + + if (ext_start == uname - 1) { + sz = ulen; + ext_start = NULL; + } else if (ext_start) { + /* + * Names which start with a dot could be just + * an extension eg. "...test". In this case Win95 + * uses the extension as the name and sets no extension. + */ + name_start = &uname[0]; + while (name_start < ext_start) { + if (!vfat_skip_char(*name_start)) + break; + name_start++; + } + if (name_start != ext_start) { + sz = ext_start - uname; + ext_start++; + } else { + sz = ulen; + ext_start = NULL; + } + } + + numtail_baselen = 6; + numtail2_baselen = 2; + for (baselen = i = 0, p = base, ip = uname; i < sz; i++, ip++) { + chl = to_shortname_char(nls, charbuf, sizeof(charbuf), + ip, &base_info); + if (chl == 0) + continue; + + if (baselen < 2 && (baselen + chl) > 2) + numtail2_baselen = baselen; + if (baselen < 6 && (baselen + chl) > 6) + numtail_baselen = baselen; + for (chi = 0; chi < chl; chi++) { + *p++ = charbuf[chi]; + baselen++; + if (baselen >= 8) + break; + } + if (baselen >= 8) { + if ((chi < chl - 1) || (ip + 1) - uname < sz) + is_shortname = 0; + break; + } + } + if (baselen == 0) { + return -EINVAL; + } + + extlen = 0; + if (ext_start) { + for (p = ext, ip = ext_start; extlen < 3 && ip < end; ip++) { + chl = to_shortname_char(nls, charbuf, sizeof(charbuf), + ip, &ext_info); + if (chl == 0) + continue; + + if ((extlen + chl) > 3) { + is_shortname = 0; + break; + } + for (chi = 0; chi < chl; chi++) { + *p++ = charbuf[chi]; + extlen++; + } + if (extlen >= 3) { + if (ip + 1 != end) + is_shortname = 0; + break; + } + } + } + ext[extlen] = '\0'; + base[baselen] = '\0'; + + /* Yes, it can happen. ".\xe5" would do it. */ + if (base[0] == DELETED_FLAG) + base[0] = 0x05; + + /* OK, at this point we know that base is not longer than 8 symbols, + * ext is not longer than 3, base is nonempty, both don't contain + * any bad symbols (lowercase transformed to uppercase). + */ + + memset(name_res, ' ', MSDOS_NAME); + memcpy(name_res, base, baselen); + memcpy(name_res + 8, ext, extlen); + *lcase = 0; + if (is_shortname && base_info.valid && ext_info.valid) { + if (vfat_find_form(dir, name_res) == 0) + return -EEXIST; + + if (opts->shortname & VFAT_SFN_CREATE_WIN95) { + return (base_info.upper && ext_info.upper); + } else if (opts->shortname & VFAT_SFN_CREATE_WINNT) { + if ((base_info.upper || base_info.lower) && + (ext_info.upper || ext_info.lower)) { + if (!base_info.upper && base_info.lower) + *lcase |= CASE_LOWER_BASE; + if (!ext_info.upper && ext_info.lower) + *lcase |= CASE_LOWER_EXT; + return 1; + } + return 0; + } else { + BUG(); + } + } + + if (opts->numtail == 0) + if (vfat_find_form(dir, name_res) < 0) + return 0; + + /* + * Try to find a unique extension. This used to + * iterate through all possibilities sequentially, + * but that gave extremely bad performance. Windows + * only tries a few cases before using random + * values for part of the base. + */ + + if (baselen > 6) { + baselen = numtail_baselen; + name_res[7] = ' '; + } + name_res[baselen] = '~'; + for (i = 1; i < 10; i++) { + name_res[baselen + 1] = i + '0'; + if (vfat_find_form(dir, name_res) < 0) + return 0; + } + + i = jiffies & 0xffff; + sz = (jiffies >> 16) & 0x7; + if (baselen > 2) { + baselen = numtail2_baselen; + name_res[7] = ' '; + } + name_res[baselen + 4] = '~'; + name_res[baselen + 5] = '1' + sz; + while (1) { + sprintf(buf, "%04X", i); + memcpy(&name_res[baselen], buf, 4); + if (vfat_find_form(dir, name_res) < 0) + break; + i -= 11; + } + return 0; +} + +/* Translate a string, including coded sequences into Unicode */ +static int +xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, + int *longlen, int *outlen, int escape, int utf8, + struct nls_table *nls) +{ + const unsigned char *ip; + unsigned char nc; + unsigned char *op; + unsigned int ec; + int i, k, fill; + int charlen; + + if (utf8) { + int name_len = strlen(name); + + *outlen = utf8_mbstowcs((wchar_t *)outname, name, PATH_MAX); + + /* + * We stripped '.'s before and set len appropriately, + * but utf8_mbstowcs doesn't care about len + */ + *outlen -= (name_len - len); + + if (*outlen > 255) + return -ENAMETOOLONG; + + op = &outname[*outlen * sizeof(wchar_t)]; + } else { + if (nls) { + for (i = 0, ip = name, op = outname, *outlen = 0; + i < len && *outlen <= 255; + *outlen += 1) + { + if (escape && (*ip == ':')) { + if (i > len - 5) + return -EINVAL; + ec = 0; + for (k = 1; k < 5; k++) { + nc = ip[k]; + ec <<= 4; + if (nc >= '0' && nc <= '9') { + ec |= nc - '0'; + continue; + } + if (nc >= 'a' && nc <= 'f') { + ec |= nc - ('a' - 10); + continue; + } + if (nc >= 'A' && nc <= 'F') { + ec |= nc - ('A' - 10); + continue; + } + return -EINVAL; + } + *op++ = ec & 0xFF; + *op++ = ec >> 8; + ip += 5; + i += 5; + } else { + if ((charlen = nls->char2uni(ip, len - i, (wchar_t *)op)) < 0) + return -EINVAL; + ip += charlen; + i += charlen; + op += 2; + } + } + if (i < len) + return -ENAMETOOLONG; + } else { + for (i = 0, ip = name, op = outname, *outlen = 0; + i < len && *outlen <= 255; + i++, *outlen += 1) + { + *op++ = *ip++; + *op++ = 0; + } + if (i < len) + return -ENAMETOOLONG; + } + } + + *longlen = *outlen; + if (*outlen % 13) { + *op++ = 0; + *op++ = 0; + *outlen += 1; + if (*outlen % 13) { + fill = 13 - (*outlen % 13); + for (i = 0; i < fill; i++) { + *op++ = 0xff; + *op++ = 0xff; + } + *outlen += fill; + } + } + + return 0; +} + +static int vfat_build_slots(struct inode *dir, const unsigned char *name, + int len, int is_dir, int cluster, + struct timespec *ts, + struct msdos_dir_slot *slots, int *nr_slots) +{ + struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb); + struct fat_mount_options *opts = &sbi->options; + struct msdos_dir_slot *ps; + struct msdos_dir_entry *de; + unsigned char cksum, lcase; + unsigned char msdos_name[MSDOS_NAME]; + wchar_t *uname; + __le16 time, date; + int err, ulen, usize, i; + loff_t offset; + + *nr_slots = 0; + + uname = __getname(); + if (!uname) + return -ENOMEM; + + err = xlate_to_uni(name, len, (unsigned char *)uname, &ulen, &usize, + opts->unicode_xlate, opts->utf8, sbi->nls_io); + if (err) + goto out_free; + + err = vfat_is_used_badchars(uname, ulen); + if (err) + goto out_free; + + err = vfat_create_shortname(dir, sbi->nls_disk, uname, ulen, + msdos_name, &lcase); + if (err < 0) + goto out_free; + else if (err == 1) { + de = (struct msdos_dir_entry *)slots; + err = 0; + goto shortname; + } + + /* build the entry of long file name */ + cksum = fat_checksum(msdos_name); + + *nr_slots = usize / 13; + for (ps = slots, i = *nr_slots; i > 0; i--, ps++) { + ps->id = i; + ps->attr = ATTR_EXT; + ps->reserved = 0; + ps->alias_checksum = cksum; + ps->start = 0; + offset = (i - 1) * 13; + fatwchar_to16(ps->name0_4, uname + offset, 5); + fatwchar_to16(ps->name5_10, uname + offset + 5, 6); + fatwchar_to16(ps->name11_12, uname + offset + 11, 2); + } + slots[0].id |= 0x40; + de = (struct msdos_dir_entry *)ps; + +shortname: + /* build the entry of 8.3 alias name */ + (*nr_slots)++; + memcpy(de->name, msdos_name, MSDOS_NAME); + de->attr = is_dir ? ATTR_DIR : ATTR_ARCH; + de->lcase = lcase; + fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc); + de->time = de->ctime = time; + de->date = de->cdate = de->adate = date; + de->ctime_cs = 0; + de->start = cpu_to_le16(cluster); + de->starthi = cpu_to_le16(cluster >> 16); + de->size = 0; +out_free: + __putname(uname); + return err; +} + +static int vfat_add_entry(struct inode *dir, struct qstr *qname, int is_dir, + int cluster, struct timespec *ts, + struct fat_slot_info *sinfo) +{ + struct msdos_dir_slot *slots; + unsigned int len; + int err, nr_slots; + + len = vfat_striptail_len(qname); + if (len == 0) + return -ENOENT; + + slots = kmalloc(sizeof(*slots) * MSDOS_SLOTS, GFP_NOFS); + if (slots == NULL) + return -ENOMEM; + + err = vfat_build_slots(dir, qname->name, len, is_dir, cluster, ts, + slots, &nr_slots); + if (err) + goto cleanup; + + err = fat_add_entries(dir, slots, nr_slots, sinfo); + if (err) + goto cleanup; + + /* update timestamp */ + dir->i_ctime = dir->i_mtime = dir->i_atime = *ts; + if (IS_DIRSYNC(dir)) + (void)fat_sync_inode(dir); + else + mark_inode_dirty(dir); +cleanup: + kfree(slots); + return err; +} + +static int vfat_find(struct inode *dir, struct qstr *qname, + struct fat_slot_info *sinfo) +{ + unsigned int len = vfat_striptail_len(qname); + if (len == 0) + return -ENOENT; + return fat_search_long(dir, qname->name, len, sinfo); +} + +static struct dentry *vfat_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; + struct dentry *alias; + int err, table; + + lock_super(sb); + table = (MSDOS_SB(sb)->options.name_check == 's') ? 2 : 0; + dentry->d_op = &vfat_dentry_ops[table]; + + err = vfat_find(dir, &dentry->d_name, &sinfo); + if (err) { + table++; + goto error; + } + inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos); + brelse(sinfo.bh); + if (IS_ERR(inode)) { + unlock_super(sb); + return ERR_CAST(inode); + } + alias = d_find_alias(inode); + if (alias) { + if (d_invalidate(alias) == 0) + dput(alias); + else { + iput(inode); + unlock_super(sb); + return alias; + } + + } +error: + unlock_super(sb); + dentry->d_op = &vfat_dentry_ops[table]; + dentry->d_time = dentry->d_parent->d_inode->i_version; + dentry = d_splice_alias(inode, dentry); + if (dentry) { + dentry->d_op = &vfat_dentry_ops[table]; + dentry->d_time = dentry->d_parent->d_inode->i_version; + } + return dentry; +} + +static int vfat_create(struct inode *dir, struct dentry *dentry, int mode, + struct nameidata *nd) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + struct fat_slot_info sinfo; + struct timespec ts; + int err; + + lock_super(sb); + + ts = CURRENT_TIME_SEC; + err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo); + if (err) + goto out; + dir->i_version++; + + 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_version++; + inode->i_mtime = inode->i_atime = inode->i_ctime = ts; + /* timestamp is already written, so mark_inode_dirty() is unneeded. */ + + dentry->d_time = dentry->d_parent->d_inode->i_version; + d_instantiate(dentry, inode); +out: + unlock_super(sb); + return err; +} + +static int vfat_rmdir(struct inode *dir, struct dentry *dentry) +{ + struct inode *inode = dentry->d_inode; + struct super_block *sb = dir->i_sb; + struct fat_slot_info sinfo; + int err; + + lock_super(sb); + + err = fat_dir_empty(inode); + if (err) + goto out; + err = vfat_find(dir, &dentry->d_name, &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_mtime = inode->i_atime = CURRENT_TIME_SEC; + fat_detach(inode); +out: + unlock_super(sb); + + return err; +} + +static int vfat_unlink(struct inode *dir, struct dentry *dentry) +{ + struct inode *inode = dentry->d_inode; + struct super_block *sb = dir->i_sb; + struct fat_slot_info sinfo; + int err; + + lock_super(sb); + + err = vfat_find(dir, &dentry->d_name, &sinfo); + if (err) + goto out; + + err = fat_remove_entries(dir, &sinfo); /* and releases bh */ + if (err) + goto out; + clear_nlink(inode); + inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC; + fat_detach(inode); +out: + unlock_super(sb); + + return err; +} + +static int vfat_mkdir(struct inode *dir, struct dentry *dentry, int mode) +{ + struct super_block *sb = dir->i_sb; + struct inode *inode; + struct fat_slot_info sinfo; + struct timespec ts; + int err, cluster; + + lock_super(sb); + + ts = CURRENT_TIME_SEC; + cluster = fat_alloc_new_dir(dir, &ts); + if (cluster < 0) { + err = cluster; + goto out; + } + err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &ts, &sinfo); + if (err) + goto out_free; + dir->i_version++; + 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_version++; + inode->i_nlink = 2; + inode->i_mtime = inode->i_atime = inode->i_ctime = ts; + /* timestamp is already written, so mark_inode_dirty() is unneeded. */ + + dentry->d_time = dentry->d_parent->d_inode->i_version; + d_instantiate(dentry, inode); + + unlock_super(sb); + return 0; + +out_free: + fat_free_clusters(dir, cluster); +out: + unlock_super(sb); + return err; +} + +static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + 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, is_dir, update_dotdot, corrupt = 0; + struct super_block *sb = old_dir->i_sb; + + old_sinfo.bh = sinfo.bh = dotdot_bh = NULL; + old_inode = old_dentry->d_inode; + new_inode = new_dentry->d_inode; + lock_super(sb); + err = vfat_find(old_dir, &old_dentry->d_name, &old_sinfo); + if (err) + 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; + } + } + + ts = CURRENT_TIME_SEC; + if (new_inode) { + 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 = vfat_add_entry(new_dir, &new_dentry->d_name, is_dir, 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_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); + unlock_super(sb); + + 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); + 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; +} + +static const struct inode_operations vfat_dir_inode_operations = { + .create = vfat_create, + .lookup = vfat_lookup, + .unlink = vfat_unlink, + .mkdir = vfat_mkdir, + .rmdir = vfat_rmdir, + .rename = vfat_rename, + .setattr = fat_setattr, + .getattr = fat_getattr, +}; + +static int vfat_fill_super(struct super_block *sb, void *data, int silent) +{ + int res; + + res = fat_fill_super(sb, data, silent, &vfat_dir_inode_operations, 1); + if (res) + return res; + + if (MSDOS_SB(sb)->options.name_check != 's') + sb->s_root->d_op = &vfat_dentry_ops[0]; + else + sb->s_root->d_op = &vfat_dentry_ops[2]; + + return 0; +} + +static int vfat_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, vfat_fill_super, + mnt); +} + +static struct file_system_type vfat_fs_type = { + .owner = THIS_MODULE, + .name = "vfat", + .get_sb = vfat_get_sb, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; + +static int __init init_vfat_fs(void) +{ + return register_filesystem(&vfat_fs_type); +} + +static void __exit exit_vfat_fs(void) +{ + unregister_filesystem(&vfat_fs_type); +} + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("VFAT filesystem support"); +MODULE_AUTHOR("Gordon Chaffee"); + +module_init(init_vfat_fs) +module_exit(exit_vfat_fs) -- cgit v1.2.3 From 9e975dae2970d22557662761c8505ce9fd165684 Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Thu, 6 Nov 2008 12:53:46 -0800 Subject: fat: split include/msdos_fs.h This splits __KERNEL__ stuff in include/msdos_fs.h into fs/fat/fat.h. Signed-off-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/cache.c | 2 +- fs/fat/dir.c | 2 +- fs/fat/fat.h | 274 +++++++++++++++++++++++++++++++++++++++++++++++++++ fs/fat/fatent.c | 1 + fs/fat/file.c | 2 +- fs/fat/inode.c | 2 +- fs/fat/misc.c | 2 +- fs/fat/namei_msdos.c | 2 +- fs/fat/namei_vfat.c | 3 +- 9 files changed, 282 insertions(+), 8 deletions(-) create mode 100644 fs/fat/fat.h (limited to 'fs/fat') diff --git a/fs/fat/cache.c b/fs/fat/cache.c index 3222f51c41cf..589edde9053c 100644 --- a/fs/fat/cache.c +++ b/fs/fat/cache.c @@ -9,8 +9,8 @@ */ #include -#include #include +#include "fat.h" /* this must be > 0. */ #define FAT_MAX_CACHE 8 diff --git a/fs/fat/dir.c b/fs/fat/dir.c index bae1c3292522..08b23ad25f1c 100644 --- a/fs/fat/dir.c +++ b/fs/fat/dir.c @@ -16,11 +16,11 @@ #include #include #include -#include #include #include #include #include +#include "fat.h" static inline loff_t fat_make_i_pos(struct super_block *sb, struct buffer_head *bh, diff --git a/fs/fat/fat.h b/fs/fat/fat.h new file mode 100644 index 000000000000..51f1c42ca5e3 --- /dev/null +++ b/fs/fat/fat.h @@ -0,0 +1,274 @@ +#ifndef _FAT_H +#define _FAT_H + +#include +#include +#include +#include +#include +#include + +/* + * vfat shortname flags + */ +#define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */ +#define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */ +#define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */ +#define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */ +#define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */ + +struct fat_mount_options { + uid_t fs_uid; + gid_t fs_gid; + unsigned short fs_fmask; + unsigned short fs_dmask; + unsigned short codepage; /* Codepage for shortname conversions */ + char *iocharset; /* Charset used for filename input/display */ + unsigned short shortname; /* flags for shortname display/create rule */ + unsigned char name_check; /* r = relaxed, n = normal, s = strict */ + unsigned short allow_utime;/* permission for setting the [am]time */ + unsigned quiet:1, /* set = fake successful chmods and chowns */ + showexec:1, /* set = only set x bit for com/exe/bat */ + sys_immutable:1, /* set = system files are immutable */ + dotsOK:1, /* set = hidden and system files are named '.filename' */ + isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ + utf8:1, /* Use of UTF-8 character set (Default) */ + unicode_xlate:1, /* create escape sequences for unhandled Unicode */ + numtail:1, /* Does first alias have a numeric '~1' type tail? */ + flush:1, /* write things quickly */ + nocase:1, /* Does this need case conversion? 0=need case conversion*/ + usefree:1, /* Use free_clusters for FAT32 */ + tz_utc:1; /* Filesystem timestamps are in UTC */ +}; + +#define FAT_HASH_BITS 8 +#define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) +#define FAT_HASH_MASK (FAT_HASH_SIZE-1) + +/* + * MS-DOS file system in-core superblock data + */ +struct msdos_sb_info { + unsigned short sec_per_clus; /* sectors/cluster */ + unsigned short cluster_bits; /* log2(cluster_size) */ + unsigned int cluster_size; /* cluster size */ + unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ + unsigned short fat_start; + unsigned long fat_length; /* FAT start & length (sec.) */ + unsigned long dir_start; + unsigned short dir_entries; /* root dir start & entries */ + unsigned long data_start; /* first data sector */ + unsigned long max_cluster; /* maximum cluster number */ + unsigned long root_cluster; /* first cluster of the root directory */ + unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ + struct mutex fat_lock; + unsigned int prev_free; /* previously allocated cluster number */ + unsigned int free_clusters; /* -1 if undefined */ + unsigned int free_clus_valid; /* is free_clusters valid? */ + struct fat_mount_options options; + struct nls_table *nls_disk; /* Codepage used on disk */ + struct nls_table *nls_io; /* Charset used for input and display */ + const void *dir_ops; /* Opaque; default directory operations */ + int dir_per_block; /* dir entries per block */ + int dir_per_block_bits; /* log2(dir_per_block) */ + + int fatent_shift; + struct fatent_operations *fatent_ops; + + spinlock_t inode_hash_lock; + struct hlist_head inode_hashtable[FAT_HASH_SIZE]; +}; + +#define FAT_CACHE_VALID 0 /* special case for valid cache */ + +/* + * MS-DOS file system inode data in memory + */ +struct msdos_inode_info { + spinlock_t cache_lru_lock; + struct list_head cache_lru; + int nr_caches; + /* for avoiding the race between fat_free() and fat_get_cluster() */ + unsigned int cache_valid_id; + + loff_t mmu_private; + int i_start; /* first cluster or 0 */ + int i_logstart; /* logical first cluster */ + int i_attrs; /* unused attribute bits */ + loff_t i_pos; /* on-disk position of directory entry or 0 */ + struct hlist_node i_fat_hash; /* hash by i_location */ + struct inode vfs_inode; +}; + +struct fat_slot_info { + loff_t i_pos; /* on-disk position of directory entry */ + loff_t slot_off; /* offset for slot or de start */ + int nr_slots; /* number of slots + 1(de) in filename */ + struct msdos_dir_entry *de; + struct buffer_head *bh; +}; + +static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) +{ + return sb->s_fs_info; +} + +static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) +{ + return container_of(inode, struct msdos_inode_info, vfs_inode); +} + +/* Return the FAT attribute byte for this inode */ +static inline u8 fat_attr(struct inode *inode) +{ + return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) | + (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) | + MSDOS_I(inode)->i_attrs; +} + +static inline unsigned char fat_checksum(const __u8 *name) +{ + unsigned char s = name[0]; + s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; + s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; + s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; + s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; + s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; + return s; +} + +static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) +{ + return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus + + sbi->data_start; +} + +static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) +{ +#ifdef __BIG_ENDIAN + while (len--) { + *dst++ = src[0] | (src[1] << 8); + src += 2; + } +#else + memcpy(dst, src, len * 2); +#endif +} + +static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) +{ +#ifdef __BIG_ENDIAN + while (len--) { + dst[0] = *src & 0x00FF; + dst[1] = (*src & 0xFF00) >> 8; + dst += 2; + src++; + } +#else + memcpy(dst, src, len * 2); +#endif +} + +/* fat/cache.c */ +extern void fat_cache_inval_inode(struct inode *inode); +extern int fat_get_cluster(struct inode *inode, int cluster, + int *fclus, int *dclus); +extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, + unsigned long *mapped_blocks); + +/* fat/dir.c */ +extern const struct file_operations fat_dir_operations; +extern int fat_search_long(struct inode *inode, const unsigned char *name, + int name_len, struct fat_slot_info *sinfo); +extern int fat_dir_empty(struct inode *dir); +extern int fat_subdirs(struct inode *dir); +extern int fat_scan(struct inode *dir, const unsigned char *name, + struct fat_slot_info *sinfo); +extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, + struct msdos_dir_entry **de, loff_t *i_pos); +extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); +extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, + struct fat_slot_info *sinfo); +extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); + +/* fat/fatent.c */ +struct fat_entry { + int entry; + union { + u8 *ent12_p[2]; + __le16 *ent16_p; + __le32 *ent32_p; + } u; + int nr_bhs; + struct buffer_head *bhs[2]; +}; + +static inline void fatent_init(struct fat_entry *fatent) +{ + fatent->nr_bhs = 0; + fatent->entry = 0; + fatent->u.ent32_p = NULL; + fatent->bhs[0] = fatent->bhs[1] = NULL; +} + +static inline void fatent_set_entry(struct fat_entry *fatent, int entry) +{ + fatent->entry = entry; + fatent->u.ent32_p = NULL; +} + +static inline void fatent_brelse(struct fat_entry *fatent) +{ + int i; + fatent->u.ent32_p = NULL; + for (i = 0; i < fatent->nr_bhs; i++) + brelse(fatent->bhs[i]); + fatent->nr_bhs = 0; + fatent->bhs[0] = fatent->bhs[1] = NULL; +} + +extern void fat_ent_access_init(struct super_block *sb); +extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, + int entry); +extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, + int new, int wait); +extern int fat_alloc_clusters(struct inode *inode, int *cluster, + int nr_cluster); +extern int fat_free_clusters(struct inode *inode, int cluster); +extern int fat_count_free_clusters(struct super_block *sb); + +/* fat/file.c */ +extern int fat_generic_ioctl(struct inode *inode, struct file *filp, + unsigned int cmd, unsigned long arg); +extern const struct file_operations fat_file_operations; +extern const struct inode_operations fat_file_inode_operations; +extern int fat_setattr(struct dentry * dentry, struct iattr * attr); +extern void fat_truncate(struct inode *inode); +extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat); + +/* fat/inode.c */ +extern void fat_attach(struct inode *inode, loff_t i_pos); +extern void fat_detach(struct inode *inode); +extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); +extern struct inode *fat_build_inode(struct super_block *sb, + struct msdos_dir_entry *de, loff_t i_pos); +extern int fat_sync_inode(struct inode *inode); +extern int fat_fill_super(struct super_block *sb, void *data, int silent, + const struct inode_operations *fs_dir_inode_ops, int isvfat); + +extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, + struct inode *i2); +/* fat/misc.c */ +extern void fat_fs_panic(struct super_block *s, const char *fmt, ...); +extern void fat_clusters_flush(struct super_block *sb); +extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); +extern int date_dos2unix(unsigned short time, unsigned short date, int tz_utc); +extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date, + int tz_utc); +extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); + +int fat_cache_init(void); +void fat_cache_destroy(void); + +#endif /* !_FAT_H */ diff --git a/fs/fat/fatent.c b/fs/fat/fatent.c index fb98b3d847ed..5b5f49061b7c 100644 --- a/fs/fat/fatent.c +++ b/fs/fat/fatent.c @@ -7,6 +7,7 @@ #include #include #include +#include "fat.h" struct fatent_operations { void (*ent_blocknr)(struct super_block *, int, int *, sector_t *); diff --git a/fs/fat/file.c b/fs/fat/file.c index ddde37025ca6..b21973f266a1 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -10,13 +10,13 @@ #include #include #include -#include #include #include #include #include #include #include +#include "fat.h" int fat_generic_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 2b2eec1283bf..3921de2013a4 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include #include @@ -28,6 +27,7 @@ #include #include #include +#include "fat.h" #ifndef CONFIG_FAT_DEFAULT_IOCHARSET /* if user don't select VFAT, this is undefined. */ diff --git a/fs/fat/misc.c b/fs/fat/misc.c index 79fb98ad36d4..91ad9be18ff9 100644 --- a/fs/fat/misc.c +++ b/fs/fat/misc.c @@ -8,8 +8,8 @@ #include #include -#include #include +#include "fat.h" /* * fat_fs_panic reports a severe file system problem and sets the file system diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c index e844b9809d27..c0a4d5cd99b2 100644 --- a/fs/fat/namei_msdos.c +++ b/fs/fat/namei_msdos.c @@ -9,8 +9,8 @@ #include #include #include -#include #include +#include "fat.h" /* Characters that are undesirable in an MS-DOS file name */ static unsigned char bad_chars[] = "*?<>|\""; diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c index 155c10b4adbd..facf3bf0211a 100644 --- a/fs/fat/namei_vfat.c +++ b/fs/fat/namei_vfat.c @@ -16,14 +16,13 @@ */ #include - #include -#include #include #include #include #include #include +#include "fat.h" static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd) { -- cgit v1.2.3 From 7decd1cb0305b97243f283fa7f4baf5fe613edeb Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Thu, 6 Nov 2008 12:53:47 -0800 Subject: fat: Fix and cleanup timestamp conversion This cleans date_dos2unix()/fat_date_unix2dos() up. New code should be much more readable. And this fixes those old functions. Those doesn't handle 2100 correctly. 2100 isn't leap year, but old one handles it as leap year. Also, with this, centi sec is handled and is fixed. Signed-off-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/dir.c | 6 ++- fs/fat/fat.h | 7 +-- fs/fat/inode.c | 34 ++++-------- fs/fat/misc.c | 148 +++++++++++++++++++++++++++++++++++++-------------- fs/fat/namei_msdos.c | 2 +- fs/fat/namei_vfat.c | 5 +- 6 files changed, 130 insertions(+), 72 deletions(-) (limited to 'fs/fat') diff --git a/fs/fat/dir.c b/fs/fat/dir.c index 08b23ad25f1c..a601c6d45bc0 100644 --- a/fs/fat/dir.c +++ b/fs/fat/dir.c @@ -1089,6 +1089,7 @@ int fat_alloc_new_dir(struct inode *dir, struct timespec *ts) struct msdos_dir_entry *de; sector_t blknr; __le16 date, time; + u8 time_cs; int err, cluster; err = fat_alloc_clusters(dir, &cluster, 1); @@ -1102,7 +1103,7 @@ int fat_alloc_new_dir(struct inode *dir, struct timespec *ts) goto error_free; } - fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc); + fat_time_unix2fat(sbi, ts, &time, &date, &time_cs); de = (struct msdos_dir_entry *)bhs[0]->b_data; /* filling the new directory slots ("." and ".." entries) */ @@ -1112,13 +1113,14 @@ int fat_alloc_new_dir(struct inode *dir, struct timespec *ts) de[0].lcase = de[1].lcase = 0; de[0].time = de[1].time = time; de[0].date = de[1].date = date; - de[0].ctime_cs = de[1].ctime_cs = 0; if (sbi->options.isvfat) { /* extra timestamps */ de[0].ctime = de[1].ctime = time; + de[0].ctime_cs = de[1].ctime_cs = time_cs; de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date; } else { de[0].ctime = de[1].ctime = 0; + de[0].ctime_cs = de[1].ctime_cs = 0; de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0; } de[0].start = cpu_to_le16(cluster); diff --git a/fs/fat/fat.h b/fs/fat/fat.h index 51f1c42ca5e3..a2a570f81719 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -263,9 +263,10 @@ extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, extern void fat_fs_panic(struct super_block *s, const char *fmt, ...); extern void fat_clusters_flush(struct super_block *sb); extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); -extern int date_dos2unix(unsigned short time, unsigned short date, int tz_utc); -extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date, - int tz_utc); +extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts, + __le16 __time, __le16 __date, u8 time_cs); +extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts, + __le16 *time, __le16 *date, u8 *time_cs); extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); int fat_cache_init(void); diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 3921de2013a4..079d9d5e0d36 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -381,22 +381,12 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de) MSDOS_I(inode)->i_attrs = de->attr & ATTR_UNUSED; inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1)) & ~((loff_t)sbi->cluster_size - 1)) >> 9; - inode->i_mtime.tv_sec = - date_dos2unix(le16_to_cpu(de->time), le16_to_cpu(de->date), - sbi->options.tz_utc); - inode->i_mtime.tv_nsec = 0; + + fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0); if (sbi->options.isvfat) { - int secs = de->ctime_cs / 100; - int csecs = de->ctime_cs % 100; - inode->i_ctime.tv_sec = - date_dos2unix(le16_to_cpu(de->ctime), - le16_to_cpu(de->cdate), - sbi->options.tz_utc) + secs; - inode->i_ctime.tv_nsec = csecs * 10000000; - inode->i_atime.tv_sec = - date_dos2unix(0, le16_to_cpu(de->adate), - sbi->options.tz_utc); - inode->i_atime.tv_nsec = 0; + fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime, + de->cdate, de->ctime_cs); + fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0); } else inode->i_ctime = inode->i_atime = inode->i_mtime; @@ -591,16 +581,14 @@ retry: raw_entry->attr = fat_attr(inode); raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart); raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16); - fat_date_unix2dos(inode->i_mtime.tv_sec, &raw_entry->time, - &raw_entry->date, sbi->options.tz_utc); + fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time, + &raw_entry->date, NULL); if (sbi->options.isvfat) { __le16 atime; - fat_date_unix2dos(inode->i_ctime.tv_sec, &raw_entry->ctime, - &raw_entry->cdate, sbi->options.tz_utc); - fat_date_unix2dos(inode->i_atime.tv_sec, &atime, - &raw_entry->adate, sbi->options.tz_utc); - raw_entry->ctime_cs = (inode->i_ctime.tv_sec & 1) * 100 + - inode->i_ctime.tv_nsec / 10000000; + fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime, + &raw_entry->cdate, &raw_entry->ctime_cs); + fat_time_unix2fat(sbi, &inode->i_atime, &atime, + &raw_entry->adate, NULL); } spin_unlock(&sbi->inode_hash_lock); mark_buffer_dirty(bh); diff --git a/fs/fat/misc.c b/fs/fat/misc.c index 91ad9be18ff9..a191e79e66a9 100644 --- a/fs/fat/misc.c +++ b/fs/fat/misc.c @@ -135,65 +135,131 @@ int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster) extern struct timezone sys_tz; +/* + * The epoch of FAT timestamp is 1980. + * : bits : value + * date: 0 - 4: day (1 -