/*

   * linux/fs/ext4/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 <linux/fs.h>

  #include <linux/jbd2.h>

  #include <linux/capability.h>

  #include <linux/ext4_fs.h>

  #include <linux/ext4_jbd2.h>

  #include <linux/time.h>
  #include <linux/compat.h>
  #include <linux/smp_lock.h>
  #include <asm/uaccess.h>

  int ext4_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,

  		unsigned long arg)
  {

  	struct ext4_inode_info *ei = EXT4_I(inode);

  	unsigned int flags;
  	unsigned short rsv_window_size;

  	ext4_debug ("cmd = %u, arg = %lu
  ", cmd, arg);

  
  	switch (cmd) {

  	case EXT4_IOC_GETFLAGS:

  		ext4_get_inode_flags(ei);

  		flags = ei->i_flags & EXT4_FL_USER_VISIBLE;

  		return put_user(flags, (int __user *) arg);

  	case EXT4_IOC_SETFLAGS: {

  		handle_t *handle = NULL;
  		int err;

  		struct ext4_iloc iloc;

  		unsigned int oldflags;
  		unsigned int jflag;
  
  		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 &= ~EXT4_DIRSYNC_FL;

  
  		mutex_lock(&inode->i_mutex);
  		oldflags = ei->i_flags;
  
  		/* The JOURNAL_DATA flag is modifiable only by root */

  		jflag = flags & EXT4_JOURNAL_DATA_FL;

  
  		/*
  		 * 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) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {

  			if (!capable(CAP_LINUX_IMMUTABLE)) {
  				mutex_unlock(&inode->i_mutex);
  				return -EPERM;
  			}
  		}
  
  		/*
  		 * The JOURNAL_DATA flag can only be changed by
  		 * the relevant capability.
  		 */

  		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {

  			if (!capable(CAP_SYS_RESOURCE)) {
  				mutex_unlock(&inode->i_mutex);
  				return -EPERM;
  			}
  		}

  		handle = ext4_journal_start(inode, 1);

  		if (IS_ERR(handle)) {
  			mutex_unlock(&inode->i_mutex);
  			return PTR_ERR(handle);
  		}
  		if (IS_SYNC(inode))
  			handle->h_sync = 1;

  		err = ext4_reserve_inode_write(handle, inode, &iloc);

  		if (err)
  			goto flags_err;

  		flags = flags & EXT4_FL_USER_MODIFIABLE;
  		flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE;

  		ei->i_flags = flags;

  		ext4_set_inode_flags(inode);

  		inode->i_ctime = ext4_current_time(inode);

  		err = ext4_mark_iloc_dirty(handle, inode, &iloc);

  flags_err:

  		ext4_journal_stop(handle);

  		if (err) {
  			mutex_unlock(&inode->i_mutex);
  			return err;
  		}

  		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
  			err = ext4_change_inode_journal_flag(inode, jflag);

  		mutex_unlock(&inode->i_mutex);
  		return err;
  	}

  	case EXT4_IOC_GETVERSION:
  	case EXT4_IOC_GETVERSION_OLD:

  		return put_user(inode->i_generation, (int __user *) arg);

  	case EXT4_IOC_SETVERSION:
  	case EXT4_IOC_SETVERSION_OLD: {

  		handle_t *handle;

  		struct ext4_iloc iloc;

  		__u32 generation;
  		int err;

  		if (!is_owner_or_cap(inode))

  			return -EPERM;
  		if (IS_RDONLY(inode))
  			return -EROFS;
  		if (get_user(generation, (int __user *) arg))
  			return -EFAULT;

  		handle = ext4_journal_start(inode, 1);

  		if (IS_ERR(handle))
  			return PTR_ERR(handle);

  		err = ext4_reserve_inode_write(handle, inode, &iloc);

  		if (err == 0) {

  			inode->i_ctime = ext4_current_time(inode);

  			inode->i_generation = generation;

  			err = ext4_mark_iloc_dirty(handle, inode, &iloc);

  		}

  		ext4_journal_stop(handle);

  		return err;
  	}

  #ifdef CONFIG_JBD2_DEBUG

  	case EXT4_IOC_WAIT_FOR_READONLY:

  		/*
  		 * This is racy - by the time we're woken up and running,
  		 * the superblock could be released.  And the module could
  		 * have been unloaded.  So sue me.
  		 *
  		 * Returns 1 if it slept, else zero.
  		 */
  		{
  			struct super_block *sb = inode->i_sb;
  			DECLARE_WAITQUEUE(wait, current);
  			int ret = 0;
  
  			set_current_state(TASK_INTERRUPTIBLE);

  			add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
  			if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) {

  				schedule();
  				ret = 1;
  			}

  			remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);

  			return ret;
  		}
  #endif

  	case EXT4_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 EXT4_IOC_SETRSVSZ: {

  
  		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
  			return -ENOTTY;
  
  		if (IS_RDONLY(inode))
  			return -EROFS;

  		if (!is_owner_or_cap(inode))

  			return -EACCES;
  
  		if (get_user(rsv_window_size, (int __user *)arg))
  			return -EFAULT;

  		if (rsv_window_size > EXT4_MAX_RESERVE_BLOCKS)
  			rsv_window_size = EXT4_MAX_RESERVE_BLOCKS;

  
  		/*
  		 * need to allocate reservation structure for this inode
  		 * before set the window size
  		 */
  		mutex_lock(&ei->truncate_mutex);
  		if (!ei->i_block_alloc_info)

  			ext4_init_block_alloc_info(inode);

  
  		if (ei->i_block_alloc_info){

  			struct ext4_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;

  			rsv->rsv_goal_size = rsv_window_size;
  		}
  		mutex_unlock(&ei->truncate_mutex);
  		return 0;
  	}

  	case EXT4_IOC_GROUP_EXTEND: {
  		ext4_fsblk_t n_blocks_count;

  		struct super_block *sb = inode->i_sb;
  		int err;
  
  		if (!capable(CAP_SYS_RESOURCE))
  			return -EPERM;
  
  		if (IS_RDONLY(inode))
  			return -EROFS;
  
  		if (get_user(n_blocks_count, (__u32 __user *)arg))
  			return -EFAULT;

  		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);

  		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
  		jbd2_journal_flush(EXT4_SB(sb)->s_journal);
  		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);

  
  		return err;
  	}

  	case EXT4_IOC_GROUP_ADD: {
  		struct ext4_new_group_data input;

  		struct super_block *sb = inode->i_sb;
  		int err;
  
  		if (!capable(CAP_SYS_RESOURCE))
  			return -EPERM;
  
  		if (IS_RDONLY(inode))
  			return -EROFS;

  		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,

  				sizeof(input)))
  			return -EFAULT;

  		err = ext4_group_add(sb, &input);

  		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
  		jbd2_journal_flush(EXT4_SB(sb)->s_journal);
  		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);

  
  		return err;
  	}

  	default:
  		return -ENOTTY;
  	}
  }
  
  #ifdef CONFIG_COMPAT

  long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

  {

  	struct inode *inode = file->f_path.dentry->d_inode;

  	int ret;
  
  	/* These are just misnamed, they actually get/put from/to user an int */
  	switch (cmd) {

  	case EXT4_IOC32_GETFLAGS:
  		cmd = EXT4_IOC_GETFLAGS;

  		break;

  	case EXT4_IOC32_SETFLAGS:
  		cmd = EXT4_IOC_SETFLAGS;

  		break;

  	case EXT4_IOC32_GETVERSION:
  		cmd = EXT4_IOC_GETVERSION;

  		break;

  	case EXT4_IOC32_SETVERSION:
  		cmd = EXT4_IOC_SETVERSION;

  		break;

  	case EXT4_IOC32_GROUP_EXTEND:
  		cmd = EXT4_IOC_GROUP_EXTEND;

  		break;

  	case EXT4_IOC32_GETVERSION_OLD:
  		cmd = EXT4_IOC_GETVERSION_OLD;

  		break;

  	case EXT4_IOC32_SETVERSION_OLD:
  		cmd = EXT4_IOC_SETVERSION_OLD;

  		break;

  #ifdef CONFIG_JBD2_DEBUG

  	case EXT4_IOC32_WAIT_FOR_READONLY:
  		cmd = EXT4_IOC_WAIT_FOR_READONLY;

  		break;
  #endif

  	case EXT4_IOC32_GETRSVSZ:
  		cmd = EXT4_IOC_GETRSVSZ;

  		break;

  	case EXT4_IOC32_SETRSVSZ:
  		cmd = EXT4_IOC_SETRSVSZ;

  		break;

  	case EXT4_IOC_GROUP_ADD:

  		break;
  	default:
  		return -ENOIOCTLCMD;
  	}
  	lock_kernel();

  	ret = ext4_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));

  	unlock_kernel();
  	return ret;
  }
  #endif