/*

   * 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/time.h>
  #include <linux/compat.h>

  #include <linux/mount.h>

  #include <linux/file.h>

  #include <asm/uaccess.h>

  #include "ext4_jbd2.h"
  #include "ext4.h"

  long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)

  {

  	struct inode *inode = filp->f_dentry->d_inode;

  	struct super_block *sb = inode->i_sb;

  	struct ext4_inode_info *ei = EXT4_I(inode);

  	unsigned int flags;

  	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, migrate = 0;

  		struct ext4_iloc iloc;

  		unsigned int oldflags;
  		unsigned int jflag;

  		if (!inode_owner_or_capable(inode))

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

  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			return err;

  		flags = ext4_mask_flags(inode->i_mode, flags);

  		err = -EPERM;

  		mutex_lock(&inode->i_mutex);

  		/* Is it quota file? Do not allow user to mess with it */

  		if (IS_NOQUOTA(inode))
  			goto flags_out;

  		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))
  				goto flags_out;

  		}
  
  		/*
  		 * The JOURNAL_DATA flag can only be changed by
  		 * the relevant capability.
  		 */

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

  			if (!capable(CAP_SYS_RESOURCE))
  				goto flags_out;

  		}

  		if (oldflags & EXT4_EXTENTS_FL) {
  			/* We don't support clearning extent flags */
  			if (!(flags & EXT4_EXTENTS_FL)) {
  				err = -EOPNOTSUPP;
  				goto flags_out;
  			}
  		} else if (flags & EXT4_EXTENTS_FL) {
  			/* migrate the file */
  			migrate = 1;
  			flags &= ~EXT4_EXTENTS_FL;
  		}

  		if (flags & EXT4_EOFBLOCKS_FL) {
  			/* we don't support adding EOFBLOCKS flag */
  			if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
  				err = -EOPNOTSUPP;
  				goto flags_out;
  			}
  		} else if (oldflags & EXT4_EOFBLOCKS_FL)
  			ext4_truncate(inode);

  		handle = ext4_journal_start(inode, 1);

  		if (IS_ERR(handle)) {

  			err = PTR_ERR(handle);
  			goto flags_out;

  		}
  		if (IS_SYNC(inode))

  			ext4_handle_sync(handle);

  		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)
  			goto flags_out;

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

  		if (err)
  			goto flags_out;
  		if (migrate)
  			err = ext4_ext_migrate(inode);

  flags_out:

  		mutex_unlock(&inode->i_mutex);

  		mnt_drop_write(filp->f_path.mnt);

  		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 (!inode_owner_or_capable(inode))

  			return -EPERM;

  
  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			return err;
  		if (get_user(generation, (int __user *) arg)) {
  			err = -EFAULT;
  			goto setversion_out;
  		}

  		handle = ext4_journal_start(inode, 1);

  		if (IS_ERR(handle)) {
  			err = PTR_ERR(handle);
  			goto setversion_out;
  		}

  		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);

  setversion_out:
  		mnt_drop_write(filp->f_path.mnt);

  		return err;
  	}

  	case EXT4_IOC_GROUP_EXTEND: {
  		ext4_fsblk_t n_blocks_count;

  		int err, err2=0;

  		err = ext4_resize_begin(sb);
  		if (err)
  			return err;

  		if (get_user(n_blocks_count, (__u32 __user *)arg))
  			return -EFAULT;

  		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
  			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
  			ext4_msg(sb, KERN_ERR,
  				 "Online resizing not supported with bigalloc");
  			return -EOPNOTSUPP;
  		}

  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			return err;

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

  		if (EXT4_SB(sb)->s_journal) {
  			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
  			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
  			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
  		}

  		if (err == 0)
  			err = err2;

  		mnt_drop_write(filp->f_path.mnt);

  		ext4_resize_end(sb);

  
  		return err;
  	}

  
  	case EXT4_IOC_MOVE_EXT: {
  		struct move_extent me;
  		struct file *donor_filp;
  		int err;

  		if (!(filp->f_mode & FMODE_READ) ||
  		    !(filp->f_mode & FMODE_WRITE))
  			return -EBADF;

  		if (copy_from_user(&me,
  			(struct move_extent __user *)arg, sizeof(me)))
  			return -EFAULT;

  		me.moved_len = 0;

  
  		donor_filp = fget(me.donor_fd);
  		if (!donor_filp)
  			return -EBADF;

  		if (!(donor_filp->f_mode & FMODE_WRITE)) {
  			err = -EBADF;
  			goto mext_out;

  		}

  		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
  			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
  			ext4_msg(sb, KERN_ERR,
  				 "Online defrag not supported with bigalloc");
  			return -EOPNOTSUPP;
  		}

  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			goto mext_out;

  		err = ext4_move_extents(filp, donor_filp, me.orig_start,
  					me.donor_start, me.len, &me.moved_len);

  		mnt_drop_write(filp->f_path.mnt);
  		if (me.moved_len > 0)
  			file_remove_suid(donor_filp);

  		if (copy_to_user((struct move_extent __user *)arg,

  				 &me, sizeof(me)))

  			err = -EFAULT;
  mext_out:
  		fput(donor_filp);

  		return err;
  	}

  	case EXT4_IOC_GROUP_ADD: {
  		struct ext4_new_group_data input;

  		int err, err2=0;

  		err = ext4_resize_begin(sb);
  		if (err)
  			return err;

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

  				sizeof(input)))
  			return -EFAULT;

  		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
  			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
  			ext4_msg(sb, KERN_ERR,
  				 "Online resizing not supported with bigalloc");
  			return -EOPNOTSUPP;
  		}

  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			return err;

  		err = ext4_group_add(sb, &input);

  		if (EXT4_SB(sb)->s_journal) {
  			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
  			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
  			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
  		}

  		if (err == 0)
  			err = err2;

  		mnt_drop_write(filp->f_path.mnt);

  		ext4_resize_end(sb);

  
  		return err;
  	}

  	case EXT4_IOC_MIGRATE:

  	{
  		int err;

  		if (!inode_owner_or_capable(inode))

  			return -EACCES;
  
  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			return err;
  		/*
  		 * inode_mutex prevent write and truncate on the file.
  		 * Read still goes through. We take i_data_sem in
  		 * ext4_ext_swap_inode_data before we switch the
  		 * inode format to prevent read.
  		 */
  		mutex_lock(&(inode->i_mutex));
  		err = ext4_ext_migrate(inode);
  		mutex_unlock(&(inode->i_mutex));
  		mnt_drop_write(filp->f_path.mnt);
  		return err;
  	}

  	case EXT4_IOC_ALLOC_DA_BLKS:
  	{
  		int err;

  		if (!inode_owner_or_capable(inode))

  			return -EACCES;
  
  		err = mnt_want_write(filp->f_path.mnt);
  		if (err)
  			return err;
  		err = ext4_alloc_da_blocks(inode);
  		mnt_drop_write(filp->f_path.mnt);
  		return err;
  	}

  	case FITRIM:
  	{

  		struct request_queue *q = bdev_get_queue(sb->s_bdev);

  		struct fstrim_range range;
  		int ret = 0;
  
  		if (!capable(CAP_SYS_ADMIN))
  			return -EPERM;

  		if (!blk_queue_discard(q))
  			return -EOPNOTSUPP;

  		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
  			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
  			ext4_msg(sb, KERN_ERR,
  				 "FITRIM not supported with bigalloc");
  			return -EOPNOTSUPP;
  		}

  		if (copy_from_user(&range, (struct fstrim_range __user *)arg,

  		    sizeof(range)))
  			return -EFAULT;

  		range.minlen = max((unsigned int)range.minlen,
  				   q->limits.discard_granularity);

  		ret = ext4_trim_fs(sb, &range);
  		if (ret < 0)
  			return ret;

  		if (copy_to_user((struct fstrim_range __user *)arg, &range,

  		    sizeof(range)))
  			return -EFAULT;
  
  		return 0;
  	}

  	default:
  		return -ENOTTY;
  	}
  }
  
  #ifdef CONFIG_COMPAT

  long ext4_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 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;

  	case EXT4_IOC32_GETRSVSZ:
  		cmd = EXT4_IOC_GETRSVSZ;

  		break;

  	case EXT4_IOC32_SETRSVSZ:
  		cmd = EXT4_IOC_SETRSVSZ;

  		break;

  	case EXT4_IOC32_GROUP_ADD: {
  		struct compat_ext4_new_group_input __user *uinput;
  		struct ext4_new_group_input input;
  		mm_segment_t old_fs;
  		int err;
  
  		uinput = compat_ptr(arg);
  		err = get_user(input.group, &uinput->group);
  		err |= get_user(input.block_bitmap, &uinput->block_bitmap);
  		err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
  		err |= get_user(input.inode_table, &uinput->inode_table);
  		err |= get_user(input.blocks_count, &uinput->blocks_count);
  		err |= get_user(input.reserved_blocks,
  				&uinput->reserved_blocks);
  		if (err)
  			return -EFAULT;
  		old_fs = get_fs();
  		set_fs(KERNEL_DS);
  		err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
  				 (unsigned long) &input);
  		set_fs(old_fs);
  		return err;
  	}

  	case EXT4_IOC_MOVE_EXT:

  	case FITRIM:

  		break;

  	default:
  		return -ENOIOCTLCMD;
  	}

  	return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));

  }
  #endif