[linux-2.6-block.git] / fs / ext4 / migrate.c

// SPDX-License-Identifier: LGPL-2.1
/*
 * Copyright IBM Corporation, 2007
 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
 *
 */

#include <linux/slab.h>
#include "ext4_jbd2.h"
#include "ext4_extents.h"

/*
 * The contiguous blocks details which can be
 * represented by a single extent
 */
struct migrate_struct {
	ext4_lblk_t first_block, last_block, curr_block;
	ext4_fsblk_t first_pblock, last_pblock;
};

static int finish_range(handle_t *handle, struct inode *inode,
				struct migrate_struct *lb)

{
	int retval = 0, needed;
	struct ext4_extent newext;
	struct ext4_ext_path *path;
	if (lb->first_pblock == 0)
		return 0;

	/* Add the extent to temp inode*/
	newext.ee_block = cpu_to_le32(lb->first_block);
	newext.ee_len   = cpu_to_le16(lb->last_block - lb->first_block + 1);
	ext4_ext_store_pblock(&newext, lb->first_pblock);
	/* Locking only for convinience since we are operating on temp inode */
	down_write(&EXT4_I(inode)->i_data_sem);
	path = ext4_find_extent(inode, lb->first_block, NULL, 0);
	if (IS_ERR(path)) {
		retval = PTR_ERR(path);
		path = NULL;
		goto err_out;
	}

	/*
	 * Calculate the credit needed to inserting this extent
	 * Since we are doing this in loop we may accumalate extra
	 * credit. But below we try to not accumalate too much
	 * of them by restarting the journal.
	 */
	needed = ext4_ext_calc_credits_for_single_extent(inode,
		    lb->last_block - lb->first_block + 1, path);

	/*
	 * Make sure the credit we accumalated is not really high
	 */
	if (needed && ext4_handle_has_enough_credits(handle,
						EXT4_RESERVE_TRANS_BLOCKS)) {
		up_write((&EXT4_I(inode)->i_data_sem));
		retval = ext4_journal_restart(handle, needed);
		down_write((&EXT4_I(inode)->i_data_sem));
		if (retval)
			goto err_out;
	} else if (needed) {
		retval = ext4_journal_extend(handle, needed);
		if (retval) {
			/*
			 * IF not able to extend the journal restart the journal
			 */
			up_write((&EXT4_I(inode)->i_data_sem));
			retval = ext4_journal_restart(handle, needed);
			down_write((&EXT4_I(inode)->i_data_sem));
			if (retval)
				goto err_out;
		}
	}
	retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
err_out:
	up_write((&EXT4_I(inode)->i_data_sem));
	ext4_ext_drop_refs(path);
	kfree(path);
	lb->first_pblock = 0;
	return retval;
}

static int update_extent_range(handle_t *handle, struct inode *inode,
			       ext4_fsblk_t pblock, struct migrate_struct *lb)
{
	int retval;
	/*
	 * See if we can add on to the existing range (if it exists)
	 */
	if (lb->first_pblock &&
		(lb->last_pblock+1 == pblock) &&
		(lb->last_block+1 == lb->curr_block)) {
		lb->last_pblock = pblock;
		lb->last_block = lb->curr_block;
		lb->curr_block++;
		return 0;
	}
	/*
	 * Start a new range.
	 */
	retval = finish_range(handle, inode, lb);
	lb->first_pblock = lb->last_pblock = pblock;
	lb->first_block = lb->last_block = lb->curr_block;
	lb->curr_block++;
	return retval;
}

static int update_ind_extent_range(handle_t *handle, struct inode *inode,
				   ext4_fsblk_t pblock,
				   struct migrate_struct *lb)
{
	struct buffer_head *bh;
	__le32 *i_data;
	int i, retval = 0;
	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;

	bh = sb_bread(inode->i_sb, pblock);
	if (!bh)
		return -EIO;

	i_data = (__le32 *)bh->b_data;
	for (i = 0; i < max_entries; i++) {
		if (i_data[i]) {
			retval = update_extent_range(handle, inode,
						le32_to_cpu(i_data[i]), lb);
			if (retval)
				break;
		} else {
			lb->curr_block++;
		}
	}
	put_bh(bh);
	return retval;

}

static int update_dind_extent_range(handle_t *handle, struct inode *inode,
				    ext4_fsblk_t pblock,
				    struct migrate_struct *lb)
{
	struct buffer_head *bh;
	__le32 *i_data;
	int i, retval = 0;
	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;

	bh = sb_bread(inode->i_sb, pblock);
	if (!bh)
		return -EIO;

	i_data = (__le32 *)bh->b_data;
	for (i = 0; i < max_entries; i++) {
		if (i_data[i]) {
			retval = update_ind_extent_range(handle, inode,
						le32_to_cpu(i_data[i]), lb);
			if (retval)
				break;
		} else {
			/* Only update the file block number */
			lb->curr_block += max_entries;
		}
	}
	put_bh(bh);
	return retval;

}

static int update_tind_extent_range(handle_t *handle, struct inode *inode,
				    ext4_fsblk_t pblock,
				    struct migrate_struct *lb)
{
	struct buffer_head *bh;
	__le32 *i_data;
	int i, retval = 0;
	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;

	bh = sb_bread(inode->i_sb, pblock);
	if (!bh)
		return -EIO;

	i_data = (__le32 *)bh->b_data;
	for (i = 0; i < max_entries; i++) {
		if (i_data[i]) {
			retval = update_dind_extent_range(handle, inode,
						le32_to_cpu(i_data[i]), lb);
			if (retval)
				break;
		} else {
			/* Only update the file block number */
			lb->curr_block += max_entries * max_entries;
		}
	}
	put_bh(bh);
	return retval;

}

static int extend_credit_for_blkdel(handle_t *handle, struct inode *inode)
{
	int retval = 0, needed;

	if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
		return 0;
	/*
	 * We are freeing a blocks. During this we touch
	 * superblock, group descriptor and block bitmap.
	 * So allocate a credit of 3. We may update
	 * quota (user and group).
	 */
	needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);

	if (ext4_journal_extend(handle, needed) != 0)
		retval = ext4_journal_restart(handle, needed);

	return retval;
}

static int free_dind_blocks(handle_t *handle,
				struct inode *inode, __le32 i_data)
{
	int i;
	__le32 *tmp_idata;
	struct buffer_head *bh;
	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;

	bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
	if (!bh)
		return -EIO;

	tmp_idata = (__le32 *)bh->b_data;
	for (i = 0; i < max_entries; i++) {
		if (tmp_idata[i]) {
			extend_credit_for_blkdel(handle, inode);
			ext4_free_blocks(handle, inode, NULL,
					 le32_to_cpu(tmp_idata[i]), 1,
					 EXT4_FREE_BLOCKS_METADATA |
					 EXT4_FREE_BLOCKS_FORGET);
		}
	}
	put_bh(bh);
	extend_credit_for_blkdel(handle, inode);
	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
			 EXT4_FREE_BLOCKS_METADATA |
			 EXT4_FREE_BLOCKS_FORGET);
	return 0;
}

static int free_tind_blocks(handle_t *handle,
				struct inode *inode, __le32 i_data)
{
	int i, retval = 0;
	__le32 *tmp_idata;
	struct buffer_head *bh;
	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;

	bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
	if (!bh)
		return -EIO;

	tmp_idata = (__le32 *)bh->b_data;
	for (i = 0; i < max_entries; i++) {
		if (tmp_idata[i]) {
			retval = free_dind_blocks(handle,
					inode, tmp_idata[i]);
			if (retval) {
				put_bh(bh);
				return retval;
			}
		}
	}
	put_bh(bh);
	extend_credit_for_blkdel(handle, inode);
	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
			 EXT4_FREE_BLOCKS_METADATA |
			 EXT4_FREE_BLOCKS_FORGET);
	return 0;
}

static int free_ind_block(handle_t *handle, struct inode *inode, __le32 *i_data)
{
	int retval;

	/* ei->i_data[EXT4_IND_BLOCK] */
	if (i_data[0]) {
		extend_credit_for_blkdel(handle, inode);
		ext4_free_blocks(handle, inode, NULL,
				le32_to_cpu(i_data[0]), 1,
				 EXT4_FREE_BLOCKS_METADATA |
				 EXT4_FREE_BLOCKS_FORGET);
	}

	/* ei->i_data[EXT4_DIND_BLOCK] */
	if (i_data[1]) {
		retval = free_dind_blocks(handle, inode, i_data[1]);
		if (retval)
			return retval;
	}

	/* ei->i_data[EXT4_TIND_BLOCK] */
	if (i_data[2]) {
		retval = free_tind_blocks(handle, inode, i_data[2]);
		if (retval)
			return retval;
	}
	return 0;
}

static int ext4_ext_swap_inode_data(handle_t *handle, struct inode *inode,
						struct inode *tmp_inode)
{
	int retval;
	__le32	i_data[3];
	struct ext4_inode_info *ei = EXT4_I(inode);
	struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);

	/*
	 * One credit accounted for writing the
	 * i_data field of the original inode
	 */
	retval = ext4_journal_extend(handle, 1);
	if (retval) {
		retval = ext4_journal_restart(handle, 1);
		if (retval)
			goto err_out;
	}

	i_data[0] = ei->i_data[EXT4_IND_BLOCK];
	i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
	i_data[2] = ei->i_data[EXT4_TIND_BLOCK];

	down_write(&EXT4_I(inode)->i_data_sem);
	/*
	 * if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
	 * happened after we started the migrate. We need to
	 * fail the migrate
	 */
	if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
		retval = -EAGAIN;
		up_write(&EXT4_I(inode)->i_data_sem);
		goto err_out;
	} else
		ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
	/*
	 * We have the extent map build with the tmp inode.
	 * Now copy the i_data across
	 */
	ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
	memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));

	/*
	 * Update i_blocks with the new blocks that got
	 * allocated while adding extents for extent index
	 * blocks.
	 *
	 * While converting to extents we need not
	 * update the original inode i_blocks for extent blocks
	 * via quota APIs. The quota update happened via tmp_inode already.
	 */
	spin_lock(&inode->i_lock);
	inode->i_blocks += tmp_inode->i_blocks;
	spin_unlock(&inode->i_lock);
	up_write(&EXT4_I(inode)->i_data_sem);

	/*
	 * We mark the inode dirty after, because we decrement the
	 * i_blocks when freeing the indirect meta-data blocks
	 */
	retval = free_ind_block(handle, inode, i_data);
	ext4_mark_inode_dirty(handle, inode);

err_out:
	return retval;
}

static int free_ext_idx(handle_t *handle, struct inode *inode,
					struct ext4_extent_idx *ix)
{
	int i, retval = 0;
	ext4_fsblk_t block;
	struct buffer_head *bh;
	struct ext4_extent_header *eh;

	block = ext4_idx_pblock(ix);
	bh = sb_bread(inode->i_sb, block);
	if (!bh)
		return -EIO;

	eh = (struct ext4_extent_header *)bh->b_data;
	if (eh->eh_depth != 0) {
		ix = EXT_FIRST_INDEX(eh);
		for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
			retval = free_ext_idx(handle, inode, ix);
			if (retval)
				break;
		}
	}
	put_bh(bh);
	extend_credit_for_blkdel(handle, inode);
	ext4_free_blocks(handle, inode, NULL, block, 1,
			 EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET);
	return retval;
}

/*
 * Free the extent meta data blocks only
 */
static int free_ext_block(handle_t *handle, struct inode *inode)
{
	int i, retval = 0;
	struct ext4_inode_info *ei = EXT4_I(inode);
	struct ext4_extent_header *eh = (struct ext4_extent_header *)ei->i_data;
	struct ext4_extent_idx *ix;
	if (eh->eh_depth == 0)
		/*
		 * No extra blocks allocated for extent meta data
		 */
		return 0;
	ix = EXT_FIRST_INDEX(eh);
	for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
		retval = free_ext_idx(handle, inode, ix);
		if (retval)
			return retval;
	}
	return retval;
}

int ext4_ext_migrate(struct inode *inode)
{
	handle_t *handle;
	int retval = 0, i;
	__le32 *i_data;
	struct ext4_inode_info *ei;
	struct inode *tmp_inode = NULL;
	struct migrate_struct lb;
	unsigned long max_entries;
	__u32 goal;
	uid_t owner[2];

	/*
	 * If the filesystem does not support extents, or the inode
	 * already is extent-based, error out.
	 */
	if (!ext4_has_feature_extents(inode->i_sb) ||
	    (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
		return -EINVAL;

	if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
		/*
		 * don't migrate fast symlink
		 */
		return retval;

	/*
	 * Worst case we can touch the allocation bitmaps, a bgd
	 * block, and a block to link in the orphan list.  We do need
	 * need to worry about credits for modifying the quota inode.
	 */
	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
		4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));

	if (IS_ERR(handle)) {
		retval = PTR_ERR(handle);
		return retval;
	}
	goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
		EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
	owner[0] = i_uid_read(inode);
	owner[1] = i_gid_read(inode);
	tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
				   S_IFREG, NULL, goal, owner, 0);
	if (IS_ERR(tmp_inode)) {
		retval = PTR_ERR(tmp_inode);
		ext4_journal_stop(handle);
		return retval;
	}
	i_size_write(tmp_inode, i_size_read(inode));
	/*
	 * Set the i_nlink to zero so it will be deleted later
	 * when we drop inode reference.
	 */
	clear_nlink(tmp_inode);

	ext4_ext_tree_init(handle, tmp_inode);
	ext4_orphan_add(handle, tmp_inode);
	ext4_journal_stop(handle);

	/*
	 * start with one credit accounted for
	 * superblock modification.
	 *
	 * For the tmp_inode we already have committed the
	 * transaction that created the inode. Later as and
	 * when we add extents we extent the journal
	 */
	/*
	 * Even though we take i_mutex we can still cause block
	 * allocation via mmap write to holes. If we have allocated
	 * new blocks we fail migrate.  New block allocation will
	 * clear EXT4_STATE_EXT_MIGRATE flag.  The flag is updated
	 * with i_data_sem held to prevent racing with block
	 * allocation.
	 */
	down_read(&EXT4_I(inode)->i_data_sem);
	ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
	up_read((&EXT4_I(inode)->i_data_sem));

	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
	if (IS_ERR(handle)) {
		/*
		 * It is impossible to update on-disk structures without
		 * a handle, so just rollback in-core changes and live other
		 * work to orphan_list_cleanup()
		 */
		ext4_orphan_del(NULL, tmp_inode);
		retval = PTR_ERR(handle);
		goto out;
	}

	ei = EXT4_I(inode);
	i_data = ei->i_data;
	memset(&lb, 0, sizeof(lb));

	/* 32 bit block address 4 bytes */
	max_entries = inode->i_sb->s_blocksize >> 2;
	for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
		if (i_data[i]) {
			retval = update_extent_range(handle, tmp_inode,
						le32_to_cpu(i_data[i]), &lb);
			if (retval)
				goto err_out;
		} else
			lb.curr_block++;
	}
	if (i_data[EXT4_IND_BLOCK]) {
		retval = update_ind_extent_range(handle, tmp_inode,
				le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
			if (retval)
				goto err_out;
	} else
		lb.curr_block += max_entries;
	if (i_data[EXT4_DIND_BLOCK]) {
		retval = update_dind_extent_range(handle, tmp_inode,
				le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
			if (retval)
				goto err_out;
	} else
		lb.curr_block += max_entries * max_entries;
	if (i_data[EXT4_TIND_BLOCK]) {
		retval = update_tind_extent_range(handle, tmp_inode,
				le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
			if (retval)
				goto err_out;
	}
	/*
	 * Build the last extent
	 */
	retval = finish_range(handle, tmp_inode, &lb);
err_out:
	if (retval)
		/*
		 * Failure case delete the extent information with the
		 * tmp_inode
		 */
		free_ext_block(handle, tmp_inode);
	else {
		retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
		if (retval)
			/*
			 * if we fail to swap inode data free the extent
			 * details of the tmp inode
			 */
			free_ext_block(handle, tmp_inode);
	}

	/* We mark the tmp_inode dirty via ext4_ext_tree_init. */
	if (ext4_journal_extend(handle, 1) != 0)
		ext4_journal_restart(handle, 1);

	/*
	 * Mark the tmp_inode as of size zero
	 */
	i_size_write(tmp_inode, 0);

	/*
	 * set the  i_blocks count to zero
	 * so that the ext4_evict_inode() does the
	 * right job
	 *
	 * We don't need to take the i_lock because
	 * the inode is not visible to user space.
	 */
	tmp_inode->i_blocks = 0;

	/* Reset the extent details */
	ext4_ext_tree_init(handle, tmp_inode);
	ext4_journal_stop(handle);
out:
	unlock_new_inode(tmp_inode);
	iput(tmp_inode);

	return retval;
}

/*
 * Migrate a simple extent-based inode to use the i_blocks[] array
 */
int ext4_ind_migrate(struct inode *inode)
{
	struct ext4_extent_header	*eh;
	struct ext4_super_block		*es = EXT4_SB(inode->i_sb)->s_es;
	struct ext4_inode_info		*ei = EXT4_I(inode);
	struct ext4_extent		*ex;
	unsigned int			i, len;
	ext4_lblk_t			start, end;
	ext4_fsblk_t			blk;
	handle_t			*handle;
	int				ret;

	if (!ext4_has_feature_extents(inode->i_sb) ||
	    (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
		return -EINVAL;

	if (ext4_has_feature_bigalloc(inode->i_sb))
		return -EOPNOTSUPP;

	/*
	 * In order to get correct extent info, force all delayed allocation
	 * blocks to be allocated, otherwise delayed allocation blocks may not
	 * be reflected and bypass the checks on extent header.
	 */
	if (test_opt(inode->i_sb, DELALLOC))
		ext4_alloc_da_blocks(inode);

	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	down_write(&EXT4_I(inode)->i_data_sem);
	ret = ext4_ext_check_inode(inode);
	if (ret)
		goto errout;

	eh = ext_inode_hdr(inode);
	ex  = EXT_FIRST_EXTENT(eh);
	if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS ||
	    eh->eh_depth != 0 || le16_to_cpu(eh->eh_entries) > 1) {
		ret = -EOPNOTSUPP;
		goto errout;
	}
	if (eh->eh_entries == 0)
		blk = len = start = end = 0;
	else {
		len = le16_to_cpu(ex->ee_len);
		blk = ext4_ext_pblock(ex);
		start = le32_to_cpu(ex->ee_block);
		end = start + len - 1;
		if (end >= EXT4_NDIR_BLOCKS) {
			ret = -EOPNOTSUPP;
			goto errout;
		}
	}

	ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
	memset(ei->i_data, 0, sizeof(ei->i_data));
	for (i = start; i <= end; i++)
		ei->i_data[i] = cpu_to_le32(blk++);
	ext4_mark_inode_dirty(handle, inode);
errout:
	ext4_journal_stop(handle);
	up_write(&EXT4_I(inode)->i_data_sem);
	return ret;
}
Commit	Line	Data
f5166768	1	// SPDX-License-Identifier: LGPL-2.1
c14c6fd5 AK	2	/*
	3	* Copyright IBM Corporation, 2007
	4	* Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
	5	*
c14c6fd5 AK	6	*/
c14c6fd5 AK	7
5a0e3ad6	8	#include <linux/slab.h>
3dcf5451	9	#include "ext4_jbd2.h"
4a092d73	10	#include "ext4_extents.h"
c14c6fd5 AK	11
	12	/*
	13	* The contiguous blocks details which can be
	14	* represented by a single extent
	15	*/
fba90ffe DM	16	struct migrate_struct {
fba90ffe DM	17	ext4_lblk_t first_block, last_block, curr_block;
c14c6fd5 AK	18	ext4_fsblk_t first_pblock, last_pblock;
	19	};
	20
	21	static int finish_range(handle_t handle, struct inode inode,
fba90ffe	22	struct migrate_struct *lb)
c14c6fd5 AK	23
	24	{
	25	int retval = 0, needed;
	26	struct ext4_extent newext;
	27	struct ext4_ext_path *path;
	28	if (lb->first_pblock == 0)
	29	return 0;
	30
	31	/* Add the extent to temp inode*/
	32	newext.ee_block = cpu_to_le32(lb->first_block);
	33	newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
	34	ext4_ext_store_pblock(&newext, lb->first_pblock);
4b1f1660 DM	35	/* Locking only for convinience since we are operating on temp inode */
4b1f1660 DM	36	down_write(&EXT4_I(inode)->i_data_sem);
ed8a1a76	37	path = ext4_find_extent(inode, lb->first_block, NULL, 0);
c14c6fd5 AK	38	if (IS_ERR(path)) {
c14c6fd5 AK	39	retval = PTR_ERR(path);
b35905c1	40	path = NULL;
c14c6fd5 AK	41	goto err_out;
	42	}
	43
	44	/*
	45	* Calculate the credit needed to inserting this extent
	46	* Since we are doing this in loop we may accumalate extra
	47	* credit. But below we try to not accumalate too much
	48	* of them by restarting the journal.
	49	*/
ee12b630 MC	50	needed = ext4_ext_calc_credits_for_single_extent(inode,
ee12b630 MC	51	lb->last_block - lb->first_block + 1, path);
c14c6fd5 AK	52
	53	/*
	54	* Make sure the credit we accumalated is not really high
	55	*/
0390131b FM	56	if (needed && ext4_handle_has_enough_credits(handle,
0390131b FM	57	EXT4_RESERVE_TRANS_BLOCKS)) {
4b1f1660	58	up_write((&EXT4_I(inode)->i_data_sem));
c14c6fd5	59	retval = ext4_journal_restart(handle, needed);
4b1f1660	60	down_write((&EXT4_I(inode)->i_data_sem));
c14c6fd5 AK	61	if (retval)
c14c6fd5 AK	62	goto err_out;
8009f9fb	63	} else if (needed) {
c14c6fd5	64	retval = ext4_journal_extend(handle, needed);
8009f9fb	65	if (retval) {
c14c6fd5 AK	66	/*
	67	* IF not able to extend the journal restart the journal
	68	*/
4b1f1660	69	up_write((&EXT4_I(inode)->i_data_sem));
c14c6fd5	70	retval = ext4_journal_restart(handle, needed);
4b1f1660	71	down_write((&EXT4_I(inode)->i_data_sem));
c14c6fd5 AK	72	if (retval)
	73	goto err_out;
	74	}
	75	}
dfe50809	76	retval = ext4_ext_insert_extent(handle, inode, &path, &newext, 0);
c14c6fd5	77	err_out:
4b1f1660	78	up_write((&EXT4_I(inode)->i_data_sem));
b7ea89ad TT	79	ext4_ext_drop_refs(path);
b7ea89ad TT	80	kfree(path);
c14c6fd5 AK	81	lb->first_pblock = 0;
	82	return retval;
	83	}
	84
	85	static int update_extent_range(handle_t handle, struct inode inode,
fba90ffe	86	ext4_fsblk_t pblock, struct migrate_struct *lb)
c14c6fd5 AK	87	{
	88	int retval;
	89	/*
	90	* See if we can add on to the existing range (if it exists)
	91	*/
	92	if (lb->first_pblock &&
	93	(lb->last_pblock+1 == pblock) &&
fba90ffe	94	(lb->last_block+1 == lb->curr_block)) {
c14c6fd5	95	lb->last_pblock = pblock;
fba90ffe DM	96	lb->last_block = lb->curr_block;
fba90ffe DM	97	lb->curr_block++;
c14c6fd5 AK	98	return 0;
	99	}
	100	/*
	101	* Start a new range.
	102	*/
	103	retval = finish_range(handle, inode, lb);
	104	lb->first_pblock = lb->last_pblock = pblock;
fba90ffe DM	105	lb->first_block = lb->last_block = lb->curr_block;
fba90ffe DM	106	lb->curr_block++;
c14c6fd5 AK	107	return retval;
	108	}
	109
	110	static int update_ind_extent_range(handle_t handle, struct inode inode,
fba90ffe DM	111	ext4_fsblk_t pblock,
fba90ffe DM	112	struct migrate_struct *lb)
c14c6fd5 AK	113	{
	114	struct buffer_head *bh;
	115	__le32 *i_data;
	116	int i, retval = 0;
c14c6fd5 AK	117	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
c14c6fd5 AK	118
c14c6fd5 AK	119	bh = sb_bread(inode->i_sb, pblock);
	120	if (!bh)
	121	return -EIO;
	122
	123	i_data = (__le32 *)bh->b_data;
fba90ffe	124	for (i = 0; i < max_entries; i++) {
c14c6fd5 AK	125	if (i_data[i]) {
c14c6fd5 AK	126	retval = update_extent_range(handle, inode,
fba90ffe	127	le32_to_cpu(i_data[i]), lb);
c14c6fd5 AK	128	if (retval)
c14c6fd5 AK	129	break;
fba90ffe DM	130	} else {
fba90ffe DM	131	lb->curr_block++;
c14c6fd5 AK	132	}
c14c6fd5 AK	133	}
c14c6fd5 AK	134	put_bh(bh);
	135	return retval;
	136
	137	}
	138
	139	static int update_dind_extent_range(handle_t handle, struct inode inode,
fba90ffe DM	140	ext4_fsblk_t pblock,
fba90ffe DM	141	struct migrate_struct *lb)
c14c6fd5 AK	142	{
	143	struct buffer_head *bh;
	144	__le32 *i_data;
	145	int i, retval = 0;
c14c6fd5 AK	146	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
c14c6fd5 AK	147
c14c6fd5 AK	148	bh = sb_bread(inode->i_sb, pblock);
	149	if (!bh)
	150	return -EIO;
	151
	152	i_data = (__le32 *)bh->b_data;
	153	for (i = 0; i < max_entries; i++) {
	154	if (i_data[i]) {
	155	retval = update_ind_extent_range(handle, inode,
fba90ffe	156	le32_to_cpu(i_data[i]), lb);
c14c6fd5 AK	157	if (retval)
	158	break;
	159	} else {
	160	/* Only update the file block number */
fba90ffe	161	lb->curr_block += max_entries;
c14c6fd5 AK	162	}
c14c6fd5 AK	163	}
c14c6fd5 AK	164	put_bh(bh);
	165	return retval;
	166
	167	}
	168
	169	static int update_tind_extent_range(handle_t handle, struct inode inode,
fba90ffe DM	170	ext4_fsblk_t pblock,
fba90ffe DM	171	struct migrate_struct *lb)
c14c6fd5 AK	172	{
	173	struct buffer_head *bh;
	174	__le32 *i_data;
	175	int i, retval = 0;
c14c6fd5 AK	176	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
c14c6fd5 AK	177
c14c6fd5 AK	178	bh = sb_bread(inode->i_sb, pblock);
	179	if (!bh)
	180	return -EIO;
	181
	182	i_data = (__le32 *)bh->b_data;
	183	for (i = 0; i < max_entries; i++) {
	184	if (i_data[i]) {
	185	retval = update_dind_extent_range(handle, inode,
fba90ffe	186	le32_to_cpu(i_data[i]), lb);
c14c6fd5 AK	187	if (retval)
c14c6fd5 AK	188	break;
fba90ffe	189	} else {
c14c6fd5	190	/* Only update the file block number */
fba90ffe DM	191	lb->curr_block += max_entries * max_entries;
fba90ffe DM	192	}
c14c6fd5	193	}
c14c6fd5 AK	194	put_bh(bh);
	195	return retval;
	196
	197	}
	198
8009f9fb AK	199	static int extend_credit_for_blkdel(handle_t handle, struct inode inode)
	200	{
	201	int retval = 0, needed;
	202
0390131b	203	if (ext4_handle_has_enough_credits(handle, EXT4_RESERVE_TRANS_BLOCKS+1))
8009f9fb AK	204	return 0;
	205	/*
	206	* We are freeing a blocks. During this we touch
	207	* superblock, group descriptor and block bitmap.
	208	* So allocate a credit of 3. We may update
	209	* quota (user and group).
	210	*/
5aca07eb	211	needed = 3 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb);
8009f9fb AK	212
	213	if (ext4_journal_extend(handle, needed) != 0)
	214	retval = ext4_journal_restart(handle, needed);
	215
	216	return retval;
	217	}
	218
c14c6fd5 AK	219	static int free_dind_blocks(handle_t *handle,
	220	struct inode *inode, __le32 i_data)
	221	{
	222	int i;
	223	__le32 *tmp_idata;
	224	struct buffer_head *bh;
	225	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
	226
	227	bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
	228	if (!bh)
	229	return -EIO;
	230
	231	tmp_idata = (__le32 *)bh->b_data;
	232	for (i = 0; i < max_entries; i++) {
8009f9fb AK	233	if (tmp_idata[i]) {
8009f9fb AK	234	extend_credit_for_blkdel(handle, inode);
7dc57615	235	ext4_free_blocks(handle, inode, NULL,
e6362609 TT	236	le32_to_cpu(tmp_idata[i]), 1,
	237	EXT4_FREE_BLOCKS_METADATA \|
	238	EXT4_FREE_BLOCKS_FORGET);
8009f9fb	239	}
c14c6fd5 AK	240	}
c14c6fd5 AK	241	put_bh(bh);
8009f9fb	242	extend_credit_for_blkdel(handle, inode);
7dc57615	243	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
e6362609 TT	244	EXT4_FREE_BLOCKS_METADATA \|
e6362609 TT	245	EXT4_FREE_BLOCKS_FORGET);
c14c6fd5 AK	246	return 0;
	247	}
	248
	249	static int free_tind_blocks(handle_t *handle,
	250	struct inode *inode, __le32 i_data)
	251	{
	252	int i, retval = 0;
	253	__le32 *tmp_idata;
	254	struct buffer_head *bh;
	255	unsigned long max_entries = inode->i_sb->s_blocksize >> 2;
	256
	257	bh = sb_bread(inode->i_sb, le32_to_cpu(i_data));
	258	if (!bh)
	259	return -EIO;
	260
	261	tmp_idata = (__le32 *)bh->b_data;
	262	for (i = 0; i < max_entries; i++) {
	263	if (tmp_idata[i]) {
	264	retval = free_dind_blocks(handle,
	265	inode, tmp_idata[i]);
	266	if (retval) {
	267	put_bh(bh);
	268	return retval;
	269	}
	270	}
	271	}
	272	put_bh(bh);
8009f9fb	273	extend_credit_for_blkdel(handle, inode);
7dc57615	274	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(i_data), 1,
e6362609 TT	275	EXT4_FREE_BLOCKS_METADATA \|
e6362609 TT	276	EXT4_FREE_BLOCKS_FORGET);
c14c6fd5 AK	277	return 0;
	278	}
	279
8009f9fb	280	static int free_ind_block(handle_t handle, struct inode inode, __le32 *i_data)
c14c6fd5 AK	281	{
c14c6fd5 AK	282	int retval;
c14c6fd5	283
8009f9fb AK	284	/* ei->i_data[EXT4_IND_BLOCK] */
	285	if (i_data[0]) {
	286	extend_credit_for_blkdel(handle, inode);
7dc57615	287	ext4_free_blocks(handle, inode, NULL,
e6362609 TT	288	le32_to_cpu(i_data[0]), 1,
	289	EXT4_FREE_BLOCKS_METADATA \|
	290	EXT4_FREE_BLOCKS_FORGET);
8009f9fb	291	}
c14c6fd5	292
8009f9fb AK	293	/* ei->i_data[EXT4_DIND_BLOCK] */
	294	if (i_data[1]) {
	295	retval = free_dind_blocks(handle, inode, i_data[1]);
c14c6fd5 AK	296	if (retval)
	297	return retval;
	298	}
	299
8009f9fb AK	300	/* ei->i_data[EXT4_TIND_BLOCK] */
	301	if (i_data[2]) {
	302	retval = free_tind_blocks(handle, inode, i_data[2]);
c14c6fd5 AK	303	if (retval)
	304	return retval;
	305	}
	306	return 0;
	307	}
	308
	309	static int ext4_ext_swap_inode_data(handle_t handle, struct inode inode,
267e4db9	310	struct inode *tmp_inode)
c14c6fd5	311	{
8009f9fb AK	312	int retval;
8009f9fb AK	313	__le32 i_data[3];
c14c6fd5 AK	314	struct ext4_inode_info *ei = EXT4_I(inode);
	315	struct ext4_inode_info *tmp_ei = EXT4_I(tmp_inode);
	316
c14c6fd5 AK	317	/*
	318	* One credit accounted for writing the
	319	* i_data field of the original inode
	320	*/
	321	retval = ext4_journal_extend(handle, 1);
267e4db9	322	if (retval) {
c14c6fd5 AK	323	retval = ext4_journal_restart(handle, 1);
	324	if (retval)
	325	goto err_out;
	326	}
	327
8009f9fb AK	328	i_data[0] = ei->i_data[EXT4_IND_BLOCK];
	329	i_data[1] = ei->i_data[EXT4_DIND_BLOCK];
	330	i_data[2] = ei->i_data[EXT4_TIND_BLOCK];
	331
	332	down_write(&EXT4_I(inode)->i_data_sem);
267e4db9	333	/*
1b9c12f4	334	* if EXT4_STATE_EXT_MIGRATE is cleared a block allocation
267e4db9 AK	335	* happened after we started the migrate. We need to
	336	* fail the migrate
	337	*/
19f5fb7a	338	if (!ext4_test_inode_state(inode, EXT4_STATE_EXT_MIGRATE)) {
267e4db9 AK	339	retval = -EAGAIN;
	340	up_write(&EXT4_I(inode)->i_data_sem);
	341	goto err_out;
	342	} else
19f5fb7a	343	ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
c14c6fd5 AK	344	/*
	345	* We have the extent map build with the tmp inode.
	346	* Now copy the i_data across
	347	*/
74e4e6db	348	ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
c14c6fd5 AK	349	memcpy(ei->i_data, tmp_ei->i_data, sizeof(ei->i_data));
	350
	351	/*
	352	* Update i_blocks with the new blocks that got
	353	* allocated while adding extents for extent index
	354	* blocks.
	355	*
	356	* While converting to extents we need not
b8a07463	357	* update the original inode i_blocks for extent blocks
c14c6fd5 AK	358	* via quota APIs. The quota update happened via tmp_inode already.
	359	*/
	360	spin_lock(&inode->i_lock);
	361	inode->i_blocks += tmp_inode->i_blocks;
	362	spin_unlock(&inode->i_lock);
8009f9fb	363	up_write(&EXT4_I(inode)->i_data_sem);
c14c6fd5	364
8009f9fb AK	365	/*
	366	* We mark the inode dirty after, because we decrement the
	367	* i_blocks when freeing the indirect meta-data blocks
	368	*/
	369	retval = free_ind_block(handle, inode, i_data);
c14c6fd5	370	ext4_mark_inode_dirty(handle, inode);
8009f9fb	371
c14c6fd5 AK	372	err_out:
	373	return retval;
	374	}
	375
	376	static int free_ext_idx(handle_t handle, struct inode inode,
	377	struct ext4_extent_idx *ix)
	378	{
	379	int i, retval = 0;
	380	ext4_fsblk_t block;
	381	struct buffer_head *bh;
	382	struct ext4_extent_header *eh;
	383
bf89d16f	384	block = ext4_idx_pblock(ix);
c14c6fd5 AK	385	bh = sb_bread(inode->i_sb, block);
	386	if (!bh)
	387	return -EIO;
	388
	389	eh = (struct ext4_extent_header *)bh->b_data;
	390	if (eh->eh_depth != 0) {
	391	ix = EXT_FIRST_INDEX(eh);
	392	for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
	393	retval = free_ext_idx(handle, inode, ix);
	394	if (retval)
	395	break;
	396	}
	397	}
	398	put_bh(bh);
8009f9fb	399	extend_credit_for_blkdel(handle, inode);
7dc57615	400	ext4_free_blocks(handle, inode, NULL, block, 1,
e6362609	401	EXT4_FREE_BLOCKS_METADATA \| EXT4_FREE_BLOCKS_FORGET);
c14c6fd5 AK	402	return retval;
	403	}
	404
	405	/*
	406	* Free the extent meta data blocks only
	407	*/
	408	static int free_ext_block(handle_t handle, struct inode inode)
	409	{
	410	int i, retval = 0;
	411	struct ext4_inode_info *ei = EXT4_I(inode);
	412	struct ext4_extent_header eh = (struct ext4_extent_header )ei->i_data;
	413	struct ext4_extent_idx *ix;
	414	if (eh->eh_depth == 0)
	415	/*
	416	* No extra blocks allocated for extent meta data
	417	*/
	418	return 0;
	419	ix = EXT_FIRST_INDEX(eh);
	420	for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ix++) {
	421	retval = free_ext_idx(handle, inode, ix);
	422	if (retval)
	423	return retval;
	424	}
	425	return retval;
c14c6fd5 AK	426	}
c14c6fd5 AK	427
2a43a878	428	int ext4_ext_migrate(struct inode *inode)
c14c6fd5 AK	429	{
	430	handle_t *handle;
	431	int retval = 0, i;
	432	__le32 *i_data;
c14c6fd5 AK	433	struct ext4_inode_info *ei;
c14c6fd5 AK	434	struct inode *tmp_inode = NULL;
fba90ffe	435	struct migrate_struct lb;
c14c6fd5	436	unsigned long max_entries;
11013911	437	__u32 goal;
5cb81dab	438	uid_t owner[2];
c14c6fd5	439
83982b6f TT	440	/*
	441	* If the filesystem does not support extents, or the inode
	442	* already is extent-based, error out.
	443	*/
e2b911c5	444	if (!ext4_has_feature_extents(inode->i_sb) \|\|
12e9b892	445	(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
c14c6fd5 AK	446	return -EINVAL;
c14c6fd5 AK	447
b8356c46 VC	448	if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
	449	/*
	450	* don't migrate fast symlink
	451	*/
	452	return retval;
	453
4b217630 TT	454	/*
	455	* Worst case we can touch the allocation bitmaps, a bgd
	456	* block, and a block to link in the orphan list. We do need
	457	* need to worry about credits for modifying the quota inode.
	458	*/
9924a92a	459	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
4b217630 TT	460	4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
4b217630 TT	461
c14c6fd5 AK	462	if (IS_ERR(handle)) {
c14c6fd5 AK	463	retval = PTR_ERR(handle);
09054264	464	return retval;
c14c6fd5	465	}
11013911 AD	466	goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
11013911 AD	467	EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
08cefc7a EB	468	owner[0] = i_uid_read(inode);
08cefc7a EB	469	owner[1] = i_gid_read(inode);
2b0143b5	470	tmp_inode = ext4_new_inode(handle, d_inode(inode->i_sb->s_root),
1b917ed8	471	S_IFREG, NULL, goal, owner, 0);
c14c6fd5	472	if (IS_ERR(tmp_inode)) {
a0cc910f	473	retval = PTR_ERR(tmp_inode);
c14c6fd5	474	ext4_journal_stop(handle);
09054264	475	return retval;
c14c6fd5 AK	476	}
	477	i_size_write(tmp_inode, i_size_read(inode));
	478	/*
f39490bc DM	479	* Set the i_nlink to zero so it will be deleted later
f39490bc DM	480	* when we drop inode reference.
c14c6fd5	481	*/
6d6b77f1	482	clear_nlink(tmp_inode);
c14c6fd5 AK	483
	484	ext4_ext_tree_init(handle, tmp_inode);
	485	ext4_orphan_add(handle, tmp_inode);
	486	ext4_journal_stop(handle);
	487
c14c6fd5 AK	488	/*
	489	* start with one credit accounted for
	490	* superblock modification.
	491	*
25985edc	492	* For the tmp_inode we already have committed the
70261f56	493	* transaction that created the inode. Later as and
c14c6fd5 AK	494	* when we add extents we extent the journal
c14c6fd5 AK	495	*/
267e4db9	496	/*
1b9c12f4 TT	497	* Even though we take i_mutex we can still cause block
	498	* allocation via mmap write to holes. If we have allocated
	499	* new blocks we fail migrate. New block allocation will
	500	* clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
	501	* with i_data_sem held to prevent racing with block
	502	* allocation.
267e4db9	503	*/
c8b459f4	504	down_read(&EXT4_I(inode)->i_data_sem);
19f5fb7a	505	ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
267e4db9 AK	506	up_read((&EXT4_I(inode)->i_data_sem));
267e4db9 AK	507
9924a92a	508	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
f39490bc DM	509	if (IS_ERR(handle)) {
	510	/*
	511	* It is impossible to update on-disk structures without
	512	* a handle, so just rollback in-core changes and live other
	513	* work to orphan_list_cleanup()
	514	*/
	515	ext4_orphan_del(NULL, tmp_inode);
	516	retval = PTR_ERR(handle);
	517	goto out;
	518	}
8009f9fb AK	519
	520	ei = EXT4_I(inode);
	521	i_data = ei->i_data;
	522	memset(&lb, 0, sizeof(lb));
	523
	524	/* 32 bit block address 4 bytes */
	525	max_entries = inode->i_sb->s_blocksize >> 2;
fba90ffe	526	for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
c14c6fd5 AK	527	if (i_data[i]) {
c14c6fd5 AK	528	retval = update_extent_range(handle, tmp_inode,
fba90ffe	529	le32_to_cpu(i_data[i]), &lb);
c14c6fd5 AK	530	if (retval)
c14c6fd5 AK	531	goto err_out;
fba90ffe DM	532	} else
fba90ffe DM	533	lb.curr_block++;
c14c6fd5 AK	534	}
	535	if (i_data[EXT4_IND_BLOCK]) {
	536	retval = update_ind_extent_range(handle, tmp_inode,
fba90ffe	537	le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
c14c6fd5 AK	538	if (retval)
	539	goto err_out;
	540	} else
fba90ffe	541	lb.curr_block += max_entries;
c14c6fd5 AK	542	if (i_data[EXT4_DIND_BLOCK]) {
c14c6fd5 AK	543	retval = update_dind_extent_range(handle, tmp_inode,
fba90ffe	544	le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
c14c6fd5 AK	545	if (retval)
	546	goto err_out;
	547	} else
fba90ffe	548	lb.curr_block += max_entries * max_entries;
c14c6fd5 AK	549	if (i_data[EXT4_TIND_BLOCK]) {
c14c6fd5 AK	550	retval = update_tind_extent_range(handle, tmp_inode,
fba90ffe	551	le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
c14c6fd5 AK	552	if (retval)
	553	goto err_out;
	554	}
	555	/*
	556	* Build the last extent
	557	*/
	558	retval = finish_range(handle, tmp_inode, &lb);
	559	err_out:
c14c6fd5 AK	560	if (retval)
	561	/*
	562	* Failure case delete the extent information with the
	563	* tmp_inode
	564	*/
	565	free_ext_block(handle, tmp_inode);
267e4db9 AK	566	else {
	567	retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
	568	if (retval)
	569	/*
	570	* if we fail to swap inode data free the extent
	571	* details of the tmp inode
	572	*/
	573	free_ext_block(handle, tmp_inode);
	574	}
8009f9fb AK	575
	576	/* We mark the tmp_inode dirty via ext4_ext_tree_init. */
	577	if (ext4_journal_extend(handle, 1) != 0)
	578	ext4_journal_restart(handle, 1);
c14c6fd5 AK	579
	580	/*
	581	* Mark the tmp_inode as of size zero
	582	*/
	583	i_size_write(tmp_inode, 0);
	584
	585	/*
	586	* set the i_blocks count to zero
58d86a50	587	* so that the ext4_evict_inode() does the
c14c6fd5 AK	588	* right job
	589	*
	590	* We don't need to take the i_lock because
	591	* the inode is not visible to user space.
	592	*/
	593	tmp_inode->i_blocks = 0;
	594
	595	/* Reset the extent details */
	596	ext4_ext_tree_init(handle, tmp_inode);
c14c6fd5	597	ext4_journal_stop(handle);
f39490bc	598	out:
a8526e84	599	unlock_new_inode(tmp_inode);
09054264	600	iput(tmp_inode);
c14c6fd5 AK	601
	602	return retval;
	603	}
0d14b098 LC	604
	605	/*
	606	* Migrate a simple extent-based inode to use the i_blocks[] array
	607	*/
	608	int ext4_ind_migrate(struct inode *inode)
	609	{
	610	struct ext4_extent_header *eh;
	611	struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
	612	struct ext4_inode_info *ei = EXT4_I(inode);
	613	struct ext4_extent *ex;
	614	unsigned int i, len;
8974fec7	615	ext4_lblk_t start, end;
0d14b098 LC	616	ext4_fsblk_t blk;
	617	handle_t *handle;
	618	int ret;
	619
e2b911c5	620	if (!ext4_has_feature_extents(inode->i_sb) \|\|
0d14b098 LC	621	(!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
	622	return -EINVAL;
	623
e2b911c5	624	if (ext4_has_feature_bigalloc(inode->i_sb))
43e50f50 LC	625	return -EOPNOTSUPP;
43e50f50 LC	626
d6f123a9 EG	627	/*
	628	* In order to get correct extent info, force all delayed allocation
	629	* blocks to be allocated, otherwise delayed allocation blocks may not
	630	* be reflected and bypass the checks on extent header.
	631	*/
	632	if (test_opt(inode->i_sb, DELALLOC))
	633	ext4_alloc_da_blocks(inode);
	634
0d14b098 LC	635	handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
	636	if (IS_ERR(handle))
	637	return PTR_ERR(handle);
	638
	639	down_write(&EXT4_I(inode)->i_data_sem);
	640	ret = ext4_ext_check_inode(inode);
	641	if (ret)
	642	goto errout;
	643
	644	eh = ext_inode_hdr(inode);
	645	ex = EXT_FIRST_EXTENT(eh);
	646	if (ext4_blocks_count(es) > EXT4_MAX_BLOCK_FILE_PHYS \|\|
	647	eh->eh_depth != 0 \|\| le16_to_cpu(eh->eh_entries) > 1) {
	648	ret = -EOPNOTSUPP;
	649	goto errout;
	650	}
	651	if (eh->eh_entries == 0)
8974fec7	652	blk = len = start = end = 0;
0d14b098 LC	653	else {
	654	len = le16_to_cpu(ex->ee_len);
	655	blk = ext4_ext_pblock(ex);
8974fec7 EG	656	start = le32_to_cpu(ex->ee_block);
8974fec7 EG	657	end = start + len - 1;
d6f123a9	658	if (end >= EXT4_NDIR_BLOCKS) {
0d14b098 LC	659	ret = -EOPNOTSUPP;
	660	goto errout;
	661	}
	662	}
	663
	664	ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
	665	memset(ei->i_data, 0, sizeof(ei->i_data));
8974fec7	666	for (i = start; i <= end; i++)
0d14b098 LC	667	ei->i_data[i] = cpu_to_le32(blk++);
	668	ext4_mark_inode_dirty(handle, inode);
	669	errout:
	670	ext4_journal_stop(handle);
	671	up_write(&EXT4_I(inode)->i_data_sem);
	672	return ret;
	673	}