/* * 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 <linux/compat.h>#include <linux/mount.h>#include <asm/current.h>#include <asm/uaccess.h>  long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg){	struct inode *inode = filp->f_dentry->d_inode;	struct ext2_inode_info *ei = EXT2_I(inode);	unsigned int flags;	unsigned short rsv_window_size;	int ret; 	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg); 	switch (cmd) {	case EXT2_IOC_GETFLAGS:		ext2_get_inode_flags(ei);		flags = ei->i_flags & EXT2_FL_USER_VISIBLE;		return put_user(flags, (int __user *) arg);	case EXT2_IOC_SETFLAGS: {		unsigned int oldflags; 		ret = mnt_want_write_file(filp);		if (ret)			return ret; 		if (!inode_owner_or_capable(inode)) {			ret = -EACCES;			goto setflags_out;		} 		if (get_user(flags, (int __user *) arg)) {			ret = -EFAULT;			goto setflags_out;		} 		flags = ext2_mask_flags(inode->i_mode, flags); 		mutex_lock(&inode->i_mutex);		/* Is it quota file? Do not allow user to mess with it */		if (IS_NOQUOTA(inode)) {			mutex_unlock(&inode->i_mutex);			ret = -EPERM;			goto setflags_out;		}		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)) {				mutex_unlock(&inode->i_mutex);				ret = -EPERM;				goto setflags_out;			}		} 		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;		mutex_unlock(&inode->i_mutex); 		mark_inode_dirty(inode);setflags_out:		mnt_drop_write_file(filp);		return ret;	}	case EXT2_IOC_GETVERSION:		return put_user(inode->i_generation, (int __user *) arg);	case EXT2_IOC_SETVERSION: {		__u32 generation; 		if (!inode_owner_or_capable(inode))			return -EPERM;		ret = mnt_want_write_file(filp);		if (ret)			return ret;		if (get_user(generation, (int __user *) arg)) {			ret = -EFAULT;			goto setversion_out;		} 		mutex_lock(&inode->i_mutex);		inode->i_ctime = CURRENT_TIME_SEC;		inode->i_generation = generation;		mutex_unlock(&inode->i_mutex); 		mark_inode_dirty(inode);setversion_out:		mnt_drop_write_file(filp);		return ret;	}	case EXT2_IOC_GETRSVSZ:		if (test_opt(inode->i_sb, RESERVATION)			&& S_ISREG(inode->i_mode)			&& ei->i_block_alloc_info) {			rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;			return put_user(rsv_window_size, (int __user *)arg);		}		return -ENOTTY;	case EXT2_IOC_SETRSVSZ: { 		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))			return -ENOTTY; 		if (!inode_owner_or_capable(inode))			return -EACCES; 		if (get_user(rsv_window_size, (int __user *)arg))			return -EFAULT; 		ret = mnt_want_write_file(filp);		if (ret)			return ret; 		if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)			rsv_window_size = EXT2_MAX_RESERVE_BLOCKS; 		/*		 * need to allocate reservation structure for this inode		 * before set the window size		 */		/*		 * XXX What lock should protect the rsv_goal_size?		 * Accessed in ext2_get_block only.  ext3 uses i_truncate.		 */		mutex_lock(&ei->truncate_mutex);		if (!ei->i_block_alloc_info)			ext2_init_block_alloc_info(inode); 		if (ei->i_block_alloc_info){			struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;			rsv->rsv_goal_size = rsv_window_size;		}		mutex_unlock(&ei->truncate_mutex);		mnt_drop_write_file(filp);		return 0;	}	default:		return -ENOTTY;	}} #ifdef CONFIG_COMPATlong ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg){	/* These are just misnamed, they actually get/put from/to user an int */	switch (cmd) {	case EXT2_IOC32_GETFLAGS:		cmd = EXT2_IOC_GETFLAGS;		break;	case EXT2_IOC32_SETFLAGS:		cmd = EXT2_IOC_SETFLAGS;		break;	case EXT2_IOC32_GETVERSION:		cmd = EXT2_IOC_GETVERSION;		break;	case EXT2_IOC32_SETVERSION:		cmd = EXT2_IOC_SETVERSION;		break;	default:		return -ENOIOCTLCMD;	}	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));}#endif