ioctl.c 18.5 KB
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/*
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 * linux/fs/ext4/ioctl.c
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 *
 * 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/capability.h>
#include <linux/time.h>
#include <linux/compat.h>
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#include <linux/mount.h>
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#include <linux/file.h>
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#include <linux/random.h>
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#include <asm/uaccess.h>
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#include "ext4_jbd2.h"
#include "ext4.h"
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#define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)

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/**
 * Swap memory between @a and @b for @len bytes.
 *
 * @a:          pointer to first memory area
 * @b:          pointer to second memory area
 * @len:        number of bytes to swap
 *
 */
static void memswap(void *a, void *b, size_t len)
{
	unsigned char *ap, *bp;

	ap = (unsigned char *)a;
	bp = (unsigned char *)b;
	while (len-- > 0) {
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		swap(*ap, *bp);
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		ap++;
		bp++;
	}
}

/**
 * Swap i_data and associated attributes between @inode1 and @inode2.
 * This function is used for the primary swap between inode1 and inode2
 * and also to revert this primary swap in case of errors.
 *
 * Therefore you have to make sure, that calling this method twice
 * will revert all changes.
 *
 * @inode1:     pointer to first inode
 * @inode2:     pointer to second inode
 */
static void swap_inode_data(struct inode *inode1, struct inode *inode2)
{
	loff_t isize;
	struct ext4_inode_info *ei1;
	struct ext4_inode_info *ei2;

	ei1 = EXT4_I(inode1);
	ei2 = EXT4_I(inode2);

	memswap(&inode1->i_flags, &inode2->i_flags, sizeof(inode1->i_flags));
	memswap(&inode1->i_version, &inode2->i_version,
		  sizeof(inode1->i_version));
	memswap(&inode1->i_blocks, &inode2->i_blocks,
		  sizeof(inode1->i_blocks));
	memswap(&inode1->i_bytes, &inode2->i_bytes, sizeof(inode1->i_bytes));
	memswap(&inode1->i_atime, &inode2->i_atime, sizeof(inode1->i_atime));
	memswap(&inode1->i_mtime, &inode2->i_mtime, sizeof(inode1->i_mtime));

	memswap(ei1->i_data, ei2->i_data, sizeof(ei1->i_data));
	memswap(&ei1->i_flags, &ei2->i_flags, sizeof(ei1->i_flags));
	memswap(&ei1->i_disksize, &ei2->i_disksize, sizeof(ei1->i_disksize));
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	ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS);
	ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS);
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	isize = i_size_read(inode1);
	i_size_write(inode1, i_size_read(inode2));
	i_size_write(inode2, isize);
}

/**
 * Swap the information from the given @inode and the inode
 * EXT4_BOOT_LOADER_INO. It will basically swap i_data and all other
 * important fields of the inodes.
 *
 * @sb:         the super block of the filesystem
 * @inode:      the inode to swap with EXT4_BOOT_LOADER_INO
 *
 */
static long swap_inode_boot_loader(struct super_block *sb,
				struct inode *inode)
{
	handle_t *handle;
	int err;
	struct inode *inode_bl;
	struct ext4_inode_info *ei_bl;
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	struct ext4_sb_info *sbi = EXT4_SB(sb);
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	if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode))
		return -EINVAL;
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	if (!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN))
		return -EPERM;
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	inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO);
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	if (IS_ERR(inode_bl))
		return PTR_ERR(inode_bl);
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	ei_bl = EXT4_I(inode_bl);

	filemap_flush(inode->i_mapping);
	filemap_flush(inode_bl->i_mapping);

	/* Protect orig inodes against a truncate and make sure,
	 * that only 1 swap_inode_boot_loader is running. */
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	lock_two_nondirectories(inode, inode_bl);
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	truncate_inode_pages(&inode->i_data, 0);
	truncate_inode_pages(&inode_bl->i_data, 0);

	/* Wait for all existing dio workers */
	ext4_inode_block_unlocked_dio(inode);
	ext4_inode_block_unlocked_dio(inode_bl);
	inode_dio_wait(inode);
	inode_dio_wait(inode_bl);

	handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2);
	if (IS_ERR(handle)) {
		err = -EINVAL;
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		goto journal_err_out;
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	}

	/* Protect extent tree against block allocations via delalloc */
	ext4_double_down_write_data_sem(inode, inode_bl);

	if (inode_bl->i_nlink == 0) {
		/* this inode has never been used as a BOOT_LOADER */
		set_nlink(inode_bl, 1);
		i_uid_write(inode_bl, 0);
		i_gid_write(inode_bl, 0);
		inode_bl->i_flags = 0;
		ei_bl->i_flags = 0;
		inode_bl->i_version = 1;
		i_size_write(inode_bl, 0);
		inode_bl->i_mode = S_IFREG;
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		if (ext4_has_feature_extents(sb)) {
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			ext4_set_inode_flag(inode_bl, EXT4_INODE_EXTENTS);
			ext4_ext_tree_init(handle, inode_bl);
		} else
			memset(ei_bl->i_data, 0, sizeof(ei_bl->i_data));
	}

	swap_inode_data(inode, inode_bl);

	inode->i_ctime = inode_bl->i_ctime = ext4_current_time(inode);

	spin_lock(&sbi->s_next_gen_lock);
	inode->i_generation = sbi->s_next_generation++;
	inode_bl->i_generation = sbi->s_next_generation++;
	spin_unlock(&sbi->s_next_gen_lock);

	ext4_discard_preallocations(inode);

	err = ext4_mark_inode_dirty(handle, inode);
	if (err < 0) {
		ext4_warning(inode->i_sb,
			"couldn't mark inode #%lu dirty (err %d)",
			inode->i_ino, err);
		/* Revert all changes: */
		swap_inode_data(inode, inode_bl);
	} else {
		err = ext4_mark_inode_dirty(handle, inode_bl);
		if (err < 0) {
			ext4_warning(inode_bl->i_sb,
				"couldn't mark inode #%lu dirty (err %d)",
				inode_bl->i_ino, err);
			/* Revert all changes: */
			swap_inode_data(inode, inode_bl);
			ext4_mark_inode_dirty(handle, inode);
		}
	}
	ext4_journal_stop(handle);
	ext4_double_up_write_data_sem(inode, inode_bl);

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journal_err_out:
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	ext4_inode_resume_unlocked_dio(inode);
	ext4_inode_resume_unlocked_dio(inode_bl);
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	unlock_two_nondirectories(inode, inode_bl);
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	iput(inode_bl);
	return err;
}

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static int uuid_is_zero(__u8 u[16])
{
	int	i;

	for (i = 0; i < 16; i++)
		if (u[i])
			return 0;
	return 1;
}

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long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
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{
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	struct inode *inode = file_inode(filp);
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	struct super_block *sb = inode->i_sb;
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	struct ext4_inode_info *ei = EXT4_I(inode);
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	unsigned int flags;

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	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
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	switch (cmd) {
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	case EXT4_IOC_GETFLAGS:
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		ext4_get_inode_flags(ei);
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		flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
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		return put_user(flags, (int __user *) arg);
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	case EXT4_IOC_SETFLAGS: {
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		handle_t *handle = NULL;
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		int err, migrate = 0;
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		struct ext4_iloc iloc;
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		unsigned int oldflags, mask, i;
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		unsigned int jflag;

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		if (!inode_owner_or_capable(inode))
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			return -EACCES;

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

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		err = mnt_want_write_file(filp);
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		if (err)
			return err;

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		flags = ext4_mask_flags(inode->i_mode, flags);
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		err = -EPERM;
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		mutex_lock(&inode->i_mutex);
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		/* Is it quota file? Do not allow user to mess with it */
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		if (IS_NOQUOTA(inode))
			goto flags_out;

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		oldflags = ei->i_flags;

		/* The JOURNAL_DATA flag is modifiable only by root */
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		jflag = flags & EXT4_JOURNAL_DATA_FL;
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		/*
		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
		 * the relevant capability.
		 *
		 * This test looks nicer. Thanks to Pauline Middelink
		 */
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		if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
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			if (!ns_capable(sb->s_user_ns, CAP_LINUX_IMMUTABLE))
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				goto flags_out;
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		}

		/*
		 * The JOURNAL_DATA flag can only be changed by
		 * the relevant capability.
		 */
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		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
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			if (!ns_capable(sb->s_user_ns, CAP_SYS_RESOURCE))
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				goto flags_out;
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		}
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		if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
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			migrate = 1;
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		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);

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		handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
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		if (IS_ERR(handle)) {
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			err = PTR_ERR(handle);
			goto flags_out;
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		}
		if (IS_SYNC(inode))
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			ext4_handle_sync(handle);
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		err = ext4_reserve_inode_write(handle, inode, &iloc);
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		if (err)
			goto flags_err;

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		for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
			if (!(mask & EXT4_FL_USER_MODIFIABLE))
				continue;
			if (mask & flags)
				ext4_set_inode_flag(inode, i);
			else
				ext4_clear_inode_flag(inode, i);
		}
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		ext4_set_inode_flags(inode);
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		inode->i_ctime = ext4_current_time(inode);
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		err = ext4_mark_iloc_dirty(handle, inode, &iloc);
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flags_err:
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		ext4_journal_stop(handle);
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		if (err)
			goto flags_out;
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		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
			err = ext4_change_inode_journal_flag(inode, jflag);
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		if (err)
			goto flags_out;
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		if (migrate) {
			if (flags & EXT4_EXTENTS_FL)
				err = ext4_ext_migrate(inode);
			else
				err = ext4_ind_migrate(inode);
		}

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flags_out:
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		mutex_unlock(&inode->i_mutex);
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		mnt_drop_write_file(filp);
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		return err;
	}
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	case EXT4_IOC_GETVERSION:
	case EXT4_IOC_GETVERSION_OLD:
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		return put_user(inode->i_generation, (int __user *) arg);
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	case EXT4_IOC_SETVERSION:
	case EXT4_IOC_SETVERSION_OLD: {
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		handle_t *handle;
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		struct ext4_iloc iloc;
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		__u32 generation;
		int err;

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		if (!inode_owner_or_capable(inode))
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			return -EPERM;
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		if (ext4_has_metadata_csum(inode->i_sb)) {
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			ext4_warning(sb, "Setting inode version is not "
				     "supported with metadata_csum enabled.");
			return -ENOTTY;
		}

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		err = mnt_want_write_file(filp);
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		if (err)
			return err;
		if (get_user(generation, (int __user *) arg)) {
			err = -EFAULT;
			goto setversion_out;
		}
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		mutex_lock(&inode->i_mutex);
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		handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
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		if (IS_ERR(handle)) {
			err = PTR_ERR(handle);
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			goto unlock_out;
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		}
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		err = ext4_reserve_inode_write(handle, inode, &iloc);
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		if (err == 0) {
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			inode->i_ctime = ext4_current_time(inode);
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			inode->i_generation = generation;
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			err = ext4_mark_iloc_dirty(handle, inode, &iloc);
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		}
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		ext4_journal_stop(handle);
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unlock_out:
		mutex_unlock(&inode->i_mutex);
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setversion_out:
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		mnt_drop_write_file(filp);
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		return err;
	}
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	case EXT4_IOC_GROUP_EXTEND: {
		ext4_fsblk_t n_blocks_count;
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		int err, err2=0;
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		err = ext4_resize_begin(sb);
		if (err)
			return err;
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		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
			err = -EFAULT;
			goto group_extend_out;
		}
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		if (ext4_has_feature_bigalloc(sb)) {
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			ext4_msg(sb, KERN_ERR,
				 "Online resizing not supported with bigalloc");
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			err = -EOPNOTSUPP;
			goto group_extend_out;
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		}

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		err = mnt_want_write_file(filp);
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		if (err)
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			goto group_extend_out;
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		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
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		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);
		}
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		if (err == 0)
			err = err2;
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		mnt_drop_write_file(filp);
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group_extend_out:
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		ext4_resize_end(sb);
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		return err;
	}
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	case EXT4_IOC_MOVE_EXT: {
		struct move_extent me;
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		struct fd donor;
		int err;
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		if (!(filp->f_mode & FMODE_READ) ||
		    !(filp->f_mode & FMODE_WRITE))
			return -EBADF;

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		if (copy_from_user(&me,
			(struct move_extent __user *)arg, sizeof(me)))
			return -EFAULT;
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		me.moved_len = 0;
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		donor = fdget(me.donor_fd);
		if (!donor.file)
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			return -EBADF;

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		if (!(donor.file->f_mode & FMODE_WRITE)) {
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			err = -EBADF;
			goto mext_out;
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		}

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		if (ext4_has_feature_bigalloc(sb)) {
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			ext4_msg(sb, KERN_ERR,
				 "Online defrag not supported with bigalloc");
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			err = -EOPNOTSUPP;
			goto mext_out;
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		}

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		err = mnt_want_write_file(filp);
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		if (err)
			goto mext_out;

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		err = ext4_move_extents(filp, donor.file, me.orig_start,
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					me.donor_start, me.len, &me.moved_len);
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		mnt_drop_write_file(filp);
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		if (copy_to_user((struct move_extent __user *)arg,
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				 &me, sizeof(me)))
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			err = -EFAULT;
mext_out:
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		fdput(donor);
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		return err;
	}

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	case EXT4_IOC_GROUP_ADD: {
		struct ext4_new_group_data input;
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		int err, err2=0;
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		err = ext4_resize_begin(sb);
		if (err)
			return err;
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		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
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				sizeof(input))) {
			err = -EFAULT;
			goto group_add_out;
		}
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		if (ext4_has_feature_bigalloc(sb)) {
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			ext4_msg(sb, KERN_ERR,
				 "Online resizing not supported with bigalloc");
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			err = -EOPNOTSUPP;
			goto group_add_out;
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		}

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		err = mnt_want_write_file(filp);
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		if (err)
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			goto group_add_out;
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		err = ext4_group_add(sb, &input);
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		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);
		}
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		if (err == 0)
			err = err2;
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		mnt_drop_write_file(filp);
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		if (!err && ext4_has_group_desc_csum(sb) &&
		    test_opt(sb, INIT_INODE_TABLE))
			err = ext4_register_li_request(sb, input.group);
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group_add_out:
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		ext4_resize_end(sb);
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		return err;
	}

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	case EXT4_IOC_MIGRATE:
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	{
		int err;
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		if (!inode_owner_or_capable(inode))
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			return -EACCES;

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		err = mnt_want_write_file(filp);
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		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));
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		mnt_drop_write_file(filp);
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		return err;
	}
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	case EXT4_IOC_ALLOC_DA_BLKS:
	{
		int err;
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		if (!inode_owner_or_capable(inode))
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			return -EACCES;

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		err = mnt_want_write_file(filp);
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		if (err)
			return err;
		err = ext4_alloc_da_blocks(inode);
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		mnt_drop_write_file(filp);
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		return err;
	}

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	case EXT4_IOC_SWAP_BOOT:
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	{
		int err;
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		if (!(filp->f_mode & FMODE_WRITE))
			return -EBADF;
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		err = mnt_want_write_file(filp);
		if (err)
			return err;
		err = swap_inode_boot_loader(sb, inode);
		mnt_drop_write_file(filp);
		return err;
	}
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	case EXT4_IOC_RESIZE_FS: {
		ext4_fsblk_t n_blocks_count;
		int err = 0, err2 = 0;
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		ext4_group_t o_group = EXT4_SB(sb)->s_groups_count;
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		if (ext4_has_feature_bigalloc(sb)) {
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			ext4_msg(sb, KERN_ERR,
				 "Online resizing not (yet) supported with bigalloc");
			return -EOPNOTSUPP;
		}

		if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
				   sizeof(__u64))) {
			return -EFAULT;
		}

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

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		err = mnt_want_write_file(filp);
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		if (err)
			goto resizefs_out;

		err = ext4_resize_fs(sb, 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;
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		mnt_drop_write_file(filp);
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		if (!err && (o_group > EXT4_SB(sb)->s_groups_count) &&
		    ext4_has_group_desc_csum(sb) &&
		    test_opt(sb, INIT_INODE_TABLE))
			err = ext4_register_li_request(sb, o_group);

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resizefs_out:
		ext4_resize_end(sb);
		return err;
	}

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	case FITRIM:
	{
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		struct request_queue *q = bdev_get_queue(sb->s_bdev);
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		struct fstrim_range range;
		int ret = 0;

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		if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
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			return -EPERM;

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

602
		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
603 604 605
		    sizeof(range)))
			return -EFAULT;

606 607
		range.minlen = max((unsigned int)range.minlen,
				   q->limits.discard_granularity);
608 609 610 611
		ret = ext4_trim_fs(sb, &range);
		if (ret < 0)
			return ret;

612
		if (copy_to_user((struct fstrim_range __user *)arg, &range,
613 614 615 616 617
		    sizeof(range)))
			return -EFAULT;

		return 0;
	}
618 619
	case EXT4_IOC_PRECACHE_EXTENTS:
		return ext4_ext_precache(inode);
620 621 622 623 624 625 626 627 628 629 630
	case EXT4_IOC_SET_ENCRYPTION_POLICY: {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct ext4_encryption_policy policy;
		int err = 0;

		if (copy_from_user(&policy,
				   (struct ext4_encryption_policy __user *)arg,
				   sizeof(policy))) {
			err = -EFAULT;
			goto encryption_policy_out;
		}
631

632 633 634 635
		err = mnt_want_write_file(filp);
		if (err)
			goto encryption_policy_out;

636
		err = ext4_process_policy(&policy, inode);
637 638

		mnt_drop_write_file(filp);
639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675
encryption_policy_out:
		return err;
#else
		return -EOPNOTSUPP;
#endif
	}
	case EXT4_IOC_GET_ENCRYPTION_PWSALT: {
		int err, err2;
		struct ext4_sb_info *sbi = EXT4_SB(sb);
		handle_t *handle;

		if (!ext4_sb_has_crypto(sb))
			return -EOPNOTSUPP;
		if (uuid_is_zero(sbi->s_es->s_encrypt_pw_salt)) {
			err = mnt_want_write_file(filp);
			if (err)
				return err;
			handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
			if (IS_ERR(handle)) {
				err = PTR_ERR(handle);
				goto pwsalt_err_exit;
			}
			err = ext4_journal_get_write_access(handle, sbi->s_sbh);
			if (err)
				goto pwsalt_err_journal;
			generate_random_uuid(sbi->s_es->s_encrypt_pw_salt);
			err = ext4_handle_dirty_metadata(handle, NULL,
							 sbi->s_sbh);
		pwsalt_err_journal:
			err2 = ext4_journal_stop(handle);
			if (err2 && !err)
				err = err2;
		pwsalt_err_exit:
			mnt_drop_write_file(filp);
			if (err)
				return err;
		}
676 677
		if (copy_to_user((void __user *) arg,
				 sbi->s_es->s_encrypt_pw_salt, 16))
678 679 680 681 682 683 684 685 686 687 688 689 690
			return -EFAULT;
		return 0;
	}
	case EXT4_IOC_GET_ENCRYPTION_POLICY: {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct ext4_encryption_policy policy;
		int err = 0;

		if (!ext4_encrypted_inode(inode))
			return -ENOENT;
		err = ext4_get_policy(inode, &policy);
		if (err)
			return err;
691
		if (copy_to_user((void __user *)arg, &policy, sizeof(policy)))
692 693 694 695 696 697
			return -EFAULT;
		return 0;
#else
		return -EOPNOTSUPP;
#endif
	}
698 699 700 701 702 703
	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
704
long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
705 706 707
{
	/* These are just misnamed, they actually get/put from/to user an int */
	switch (cmd) {
708 709
	case EXT4_IOC32_GETFLAGS:
		cmd = EXT4_IOC_GETFLAGS;
710
		break;
711 712
	case EXT4_IOC32_SETFLAGS:
		cmd = EXT4_IOC_SETFLAGS;
713
		break;
714 715
	case EXT4_IOC32_GETVERSION:
		cmd = EXT4_IOC_GETVERSION;
716
		break;
717 718
	case EXT4_IOC32_SETVERSION:
		cmd = EXT4_IOC_SETVERSION;
719
		break;
720 721
	case EXT4_IOC32_GROUP_EXTEND:
		cmd = EXT4_IOC_GROUP_EXTEND;
722
		break;
723 724
	case EXT4_IOC32_GETVERSION_OLD:
		cmd = EXT4_IOC_GETVERSION_OLD;
725
		break;
726 727
	case EXT4_IOC32_SETVERSION_OLD:
		cmd = EXT4_IOC_SETVERSION_OLD;
728
		break;
729 730
	case EXT4_IOC32_GETRSVSZ:
		cmd = EXT4_IOC_GETRSVSZ;
731
		break;
732 733
	case EXT4_IOC32_SETRSVSZ:
		cmd = EXT4_IOC_SETRSVSZ;
734
		break;
735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757
	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;
	}
758
	case EXT4_IOC_MOVE_EXT:
759
	case EXT4_IOC_RESIZE_FS:
760
	case EXT4_IOC_PRECACHE_EXTENTS:
761 762 763
	case EXT4_IOC_SET_ENCRYPTION_POLICY:
	case EXT4_IOC_GET_ENCRYPTION_PWSALT:
	case EXT4_IOC_GET_ENCRYPTION_POLICY:
764
		break;
765 766 767
	default:
		return -ENOIOCTLCMD;
	}
768
	return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
769 770
}
#endif