/* * linux/fs/ext2/ioctl.c * * Copyright (C) 1993, 1994, 1995 * Remy Card (card@masi.ibp.fr) * Laboratoire MASI - Institut Blaise Pascal * Universite Pierre et Marie Curie (Paris VI) */ #include "ext2.h"#include <linux/capability.h>#include <linux/time.h>#include <linux/sched.h>#include <asm/current.h>#include <asm/uaccess.h>  int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,		unsigned long arg){	struct ext2_inode_info *ei = EXT2_I(inode);	unsigned int flags; 	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg); 	switch (cmd) {	case EXT2_IOC_GETFLAGS:		flags = ei->i_flags & EXT2_FL_USER_VISIBLE;		return put_user(flags, (int __user *) arg);	case EXT2_IOC_SETFLAGS: {		unsigned int oldflags; 		if (IS_RDONLY(inode))			return -EROFS; 		if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))			return -EACCES; 		if (get_user(flags, (int __user *) arg))			return -EFAULT; 		if (!S_ISDIR(inode->i_mode))			flags &= ~EXT2_DIRSYNC_FL; 		oldflags = ei->i_flags; 		/*		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by		 * the relevant capability.		 *		 * This test looks nicer. Thanks to Pauline Middelink		 */		if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {			if (!capable(CAP_LINUX_IMMUTABLE))				return -EPERM;		} 		flags = flags & EXT2_FL_USER_MODIFIABLE;		flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;		ei->i_flags = flags; 		ext2_set_inode_flags(inode);		inode->i_ctime = CURRENT_TIME_SEC;		mark_inode_dirty(inode);		return 0;	}	case EXT2_IOC_GETVERSION:		return put_user(inode->i_generation, (int __user *) arg);	case EXT2_IOC_SETVERSION:		if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))			return -EPERM;		if (IS_RDONLY(inode))			return -EROFS;		if (get_user(inode->i_generation, (int __user *) arg))			return -EFAULT;			inode->i_ctime = CURRENT_TIME_SEC;		mark_inode_dirty(inode);		return 0;	default:		return -ENOTTY;	}}