diff options
Diffstat (limited to 'fs/ubifs/ioctl.c')
| -rw-r--r-- | fs/ubifs/ioctl.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c new file mode 100644 index 00000000000..5e82cffe969 --- /dev/null +++ b/fs/ubifs/ioctl.c @@ -0,0 +1,204 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * Copyright (C) 2006, 2007 University of Szeged, Hungary + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Zoltan Sogor + * Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* This file implements EXT2-compatible extended attribute ioctl() calls */ + +#include <linux/compat.h> +#include <linux/smp_lock.h> +#include <linux/mount.h> +#include "ubifs.h" + +/** + * ubifs_set_inode_flags - set VFS inode flags. + * @inode: VFS inode to set flags for + * + * This function propagates flags from UBIFS inode object to VFS inode object. + */ +void ubifs_set_inode_flags(struct inode *inode) +{ + unsigned int flags = ubifs_inode(inode)->flags; + + inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_DIRSYNC); + if (flags & UBIFS_SYNC_FL) + inode->i_flags |= S_SYNC; + if (flags & UBIFS_APPEND_FL) + inode->i_flags |= S_APPEND; + if (flags & UBIFS_IMMUTABLE_FL) + inode->i_flags |= S_IMMUTABLE; + if (flags & UBIFS_DIRSYNC_FL) + inode->i_flags |= S_DIRSYNC; +} + +/* + * ioctl2ubifs - convert ioctl inode flags to UBIFS inode flags. + * @ioctl_flags: flags to convert + * + * This function convert ioctl flags (@FS_COMPR_FL, etc) to UBIFS inode flags + * (@UBIFS_COMPR_FL, etc). + */ +static int ioctl2ubifs(int ioctl_flags) +{ + int ubifs_flags = 0; + + if (ioctl_flags & FS_COMPR_FL) + ubifs_flags |= UBIFS_COMPR_FL; + if (ioctl_flags & FS_SYNC_FL) + ubifs_flags |= UBIFS_SYNC_FL; + if (ioctl_flags & FS_APPEND_FL) + ubifs_flags |= UBIFS_APPEND_FL; + if (ioctl_flags & FS_IMMUTABLE_FL) + ubifs_flags |= UBIFS_IMMUTABLE_FL; + if (ioctl_flags & FS_DIRSYNC_FL) + ubifs_flags |= UBIFS_DIRSYNC_FL; + + return ubifs_flags; +} + +/* + * ubifs2ioctl - convert UBIFS inode flags to ioctl inode flags. + * @ubifs_flags: flags to convert + * + * This function convert UBIFS (@UBIFS_COMPR_FL, etc) to ioctl flags + * (@FS_COMPR_FL, etc). + */ +static int ubifs2ioctl(int ubifs_flags) +{ + int ioctl_flags = 0; + + if (ubifs_flags & UBIFS_COMPR_FL) + ioctl_flags |= FS_COMPR_FL; + if (ubifs_flags & UBIFS_SYNC_FL) + ioctl_flags |= FS_SYNC_FL; + if (ubifs_flags & UBIFS_APPEND_FL) + ioctl_flags |= FS_APPEND_FL; + if (ubifs_flags & UBIFS_IMMUTABLE_FL) + ioctl_flags |= FS_IMMUTABLE_FL; + if (ubifs_flags & UBIFS_DIRSYNC_FL) + ioctl_flags |= FS_DIRSYNC_FL; + + return ioctl_flags; +} + +static int setflags(struct inode *inode, int flags) +{ + int oldflags, err, release; + struct ubifs_inode *ui = ubifs_inode(inode); + struct ubifs_info *c = inode->i_sb->s_fs_info; + struct ubifs_budget_req req = { .dirtied_ino = 1, + .dirtied_ino_d = ui->data_len }; + + err = ubifs_budget_space(c, &req); + if (err) + return err; + + /* + * The IMMUTABLE and APPEND_ONLY flags can only be changed by + * the relevant capability. + */ + mutex_lock(&ui->ui_mutex); + oldflags = ubifs2ioctl(ui->flags); + if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { + if (!capable(CAP_LINUX_IMMUTABLE)) { + err = -EPERM; + goto out_unlock; + } + } + + ui->flags = ioctl2ubifs(flags); + ubifs_set_inode_flags(inode); + inode->i_ctime = ubifs_current_time(inode); + release = ui->dirty; + mark_inode_dirty_sync(inode); + mutex_unlock(&ui->ui_mutex); + + if (release) + ubifs_release_budget(c, &req); + if (IS_SYNC(inode)) + err = write_inode_now(inode, 1); + return err; + +out_unlock: + ubifs_err("can't modify inode %lu attributes", inode->i_ino); + mutex_unlock(&ui->ui_mutex); + ubifs_release_budget(c, &req); + return err; +} + +long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + int flags, err; + struct inode *inode = file->f_path.dentry->d_inode; + + switch (cmd) { + case FS_IOC_GETFLAGS: + flags = ubifs2ioctl(ubifs_inode(inode)->flags); + + return put_user(flags, (int __user *) arg); + + case FS_IOC_SETFLAGS: { + if (IS_RDONLY(inode)) + return -EROFS; + + if (!is_owner_or_cap(inode)) + return -EACCES; + + if (get_user(flags, (int __user *) arg)) + return -EFAULT; + + if (!S_ISDIR(inode->i_mode)) + flags &= ~FS_DIRSYNC_FL; + + /* + * Make sure the file-system is read-write and make sure it + * will not become read-only while we are changing the flags. + */ + err = mnt_want_write(file->f_path.mnt); + if (err) + return err; + err = setflags(inode, flags); + mnt_drop_write(file->f_path.mnt); + return err; + } + + default: + return -ENOTTY; + } +} + +#ifdef CONFIG_COMPAT +long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + case FS_IOC32_GETFLAGS: + cmd = FS_IOC_GETFLAGS; + break; + case FS_IOC32_SETFLAGS: + cmd = FS_IOC_SETFLAGS; + break; + default: + return -ENOIOCTLCMD; + } + return ubifs_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); +} +#endif |