fs/ext4/orphan.c - linux - Git at Google

 /*
  * Ext4 orphan inode handling
  */
 #include <linux/fs.h>
 #include <linux/quotaops.h>
 #include <linux/buffer_head.h>

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

 static int ext4_orphan_file_add(handle_t *handle, struct inode *inode)
 {
 	int i, j, start;
 	struct ext4_orphan_info *oi = &EXT4_SB(inode->i_sb)->s_orphan_info;
 	int ret = 0;
 	bool found = false;
 	__le32 *bdata;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(inode->i_sb);
 	int looped = 0;

 	/*
 	 * Find block with free orphan entry. Use CPU number for a naive hash
 	 * for a search start in the orphan file
 	 */
 	start = raw_smp_processor_id()*13 % oi->of_blocks;
 	i = start;
 	do {
 		if (atomic_dec_if_positive(&oi->of_binfo[i].ob_free_entries)
 		    >= 0) {
 			found = true;
 			break;
 		}
 		if (++i >= oi->of_blocks)
 			i = 0;
 	} while (i != start);

 	if (!found) {
 		/*
 		 * For now we don't grow or shrink orphan file. We just use
 		 * whatever was allocated at mke2fs time. The additional
 		 * credits we would have to reserve for each orphan inode
 		 * operation just don't seem worth it.
 		 */
 		return -ENOSPC;
 	}

 	ret = ext4_journal_get_write_access(handle, inode->i_sb,
 				oi->of_binfo[i].ob_bh, EXT4_JTR_ORPHAN_FILE);
 	if (ret) {
 		atomic_inc(&oi->of_binfo[i].ob_free_entries);
 		return ret;
 	}

 	bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
 	/* Find empty slot in a block */
 	j = 0;
 	do {
 		if (looped) {
 			/*
 			 * Did we walk through the block several times without
 			 * finding free entry? It is theoretically possible
 			 * if entries get constantly allocated and freed or
 			 * if the block is corrupted. Avoid indefinite looping
 			 * and bail. We'll use orphan list instead.
 			 */
 			if (looped > 3) {
 				atomic_inc(&oi->of_binfo[i].ob_free_entries);
 				return -ENOSPC;
 			}
 			cond_resched();
 		}
 		while (bdata[j]) {
 			if (++j >= inodes_per_ob) {
 				j = 0;
 				looped++;
 			}
 		}
 	} while (cmpxchg(&bdata[j], (__le32)0, cpu_to_le32(inode->i_ino)) !=
 		 (__le32)0);

 	EXT4_I(inode)->i_orphan_idx = i * inodes_per_ob + j;
 	ext4_set_inode_state(inode, EXT4_STATE_ORPHAN_FILE);

 	return ext4_handle_dirty_metadata(handle, NULL, oi->of_binfo[i].ob_bh);
 }

 /*
  * ext4_orphan_add() links an unlinked or truncated inode into a list of
  * such inodes, starting at the superblock, in case we crash before the
  * file is closed/deleted, or in case the inode truncate spans multiple
  * transactions and the last transaction is not recovered after a crash.
  *
  * At filesystem recovery time, we walk this list deleting unlinked
  * inodes and truncating linked inodes in ext4_orphan_cleanup().
  *
  * Orphan list manipulation functions must be called under i_rwsem unless
  * we are just creating the inode or deleting it.
  */
 int ext4_orphan_add(handle_t *handle, struct inode *inode)
 {
 	struct super_block *sb = inode->i_sb;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	struct ext4_iloc iloc;
 	int err = 0, rc;
 	bool dirty = false;

 	if (!sbi->s_journal || is_bad_inode(inode))
 		return 0;

 	WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
 		     !inode_is_locked(inode));
 	/*
 	 * Inode orphaned in orphan file or in orphan list?
 	 */
 	if (ext4_test_inode_state(inode, EXT4_STATE_ORPHAN_FILE) ||
 	    !list_empty(&EXT4_I(inode)->i_orphan))
 		return 0;

 	/*
 	 * Orphan handling is only valid for files with data blocks
 	 * being truncated, or files being unlinked. Note that we either
 	 * hold i_rwsem, or the inode can not be referenced from outside,
 	 * so i_nlink should not be bumped due to race
 	 */
 	ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 		  S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);

 	if (sbi->s_orphan_info.of_blocks) {
 		err = ext4_orphan_file_add(handle, inode);
 		/*
 		 * Fallback to normal orphan list of orphan file is
 		 * out of space
 		 */
 		if (err != -ENOSPC)
 			return err;
 	}

 	BUFFER_TRACE(sbi->s_sbh, "get_write_access");
 	err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh,
 					    EXT4_JTR_NONE);
 	if (err)
 		goto out;

 	err = ext4_reserve_inode_write(handle, inode, &iloc);
 	if (err)
 		goto out;

 	mutex_lock(&sbi->s_orphan_lock);
 	/*
 	 * Due to previous errors inode may be already a part of on-disk
 	 * orphan list. If so skip on-disk list modification.
 	 */
 	if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
 	    (le32_to_cpu(sbi->s_es->s_inodes_count))) {
 		/* Insert this inode at the head of the on-disk orphan list */
 		NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
 		lock_buffer(sbi->s_sbh);
 		sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
 		ext4_superblock_csum_set(sb);
 		unlock_buffer(sbi->s_sbh);
 		dirty = true;
 	}
 	list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
 	mutex_unlock(&sbi->s_orphan_lock);

 	if (dirty) {
 		err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
 		rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
 		if (!err)
 			err = rc;
 		if (err) {
 			/*
 			 * We have to remove inode from in-memory list if
 			 * addition to on disk orphan list failed. Stray orphan
 			 * list entries can cause panics at unmount time.
 			 */
 			mutex_lock(&sbi->s_orphan_lock);
 			list_del_init(&EXT4_I(inode)->i_orphan);
 			mutex_unlock(&sbi->s_orphan_lock);
 		}
 	} else
 		brelse(iloc.bh);

 	jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
 	jbd_debug(4, "orphan inode %lu will point to %d\n",
 			inode->i_ino, NEXT_ORPHAN(inode));
 out:
 	ext4_std_error(sb, err);
 	return err;
 }

 static int ext4_orphan_file_del(handle_t *handle, struct inode *inode)
 {
 	struct ext4_orphan_info *oi = &EXT4_SB(inode->i_sb)->s_orphan_info;
 	__le32 *bdata;
 	int blk, off;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(inode->i_sb);
 	int ret = 0;

 	if (!handle)
 		goto out;
 	blk = EXT4_I(inode)->i_orphan_idx / inodes_per_ob;
 	off = EXT4_I(inode)->i_orphan_idx % inodes_per_ob;
 	if (WARN_ON_ONCE(blk >= oi->of_blocks))
 		goto out;

 	ret = ext4_journal_get_write_access(handle, inode->i_sb,
 				oi->of_binfo[blk].ob_bh, EXT4_JTR_ORPHAN_FILE);
 	if (ret)
 		goto out;

 	bdata = (__le32 *)(oi->of_binfo[blk].ob_bh->b_data);
 	bdata[off] = 0;
 	atomic_inc(&oi->of_binfo[blk].ob_free_entries);
 	ret = ext4_handle_dirty_metadata(handle, NULL, oi->of_binfo[blk].ob_bh);
 out:
 	ext4_clear_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
 	INIT_LIST_HEAD(&EXT4_I(inode)->i_orphan);

 	return ret;
 }

 /*
  * ext4_orphan_del() removes an unlinked or truncated inode from the list
  * of such inodes stored on disk, because it is finally being cleaned up.
  */
 int ext4_orphan_del(handle_t *handle, struct inode *inode)
 {
 	struct list_head *prev;
 	struct ext4_inode_info *ei = EXT4_I(inode);
 	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 	__u32 ino_next;
 	struct ext4_iloc iloc;
 	int err = 0;

 	if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
 		return 0;

 	WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
 		     !inode_is_locked(inode));
 	if (ext4_test_inode_state(inode, EXT4_STATE_ORPHAN_FILE))
 		return ext4_orphan_file_del(handle, inode);

 	/* Do this quick check before taking global s_orphan_lock. */
 	if (list_empty(&ei->i_orphan))
 		return 0;

 	if (handle) {
 		/* Grab inode buffer early before taking global s_orphan_lock */
 		err = ext4_reserve_inode_write(handle, inode, &iloc);
 	}

 	mutex_lock(&sbi->s_orphan_lock);
 	jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);

 	prev = ei->i_orphan.prev;
 	list_del_init(&ei->i_orphan);

 	/* If we're on an error path, we may not have a valid
 	 * transaction handle with which to update the orphan list on
 	 * disk, but we still need to remove the inode from the linked
 	 * list in memory. */
 	if (!handle || err) {
 		mutex_unlock(&sbi->s_orphan_lock);
 		goto out_err;
 	}

 	ino_next = NEXT_ORPHAN(inode);
 	if (prev == &sbi->s_orphan) {
 		jbd_debug(4, "superblock will point to %u\n", ino_next);
 		BUFFER_TRACE(sbi->s_sbh, "get_write_access");
 		err = ext4_journal_get_write_access(handle, inode->i_sb,
 						    sbi->s_sbh, EXT4_JTR_NONE);
 		if (err) {
 			mutex_unlock(&sbi->s_orphan_lock);
 			goto out_brelse;
 		}
 		lock_buffer(sbi->s_sbh);
 		sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
 		ext4_superblock_csum_set(inode->i_sb);
 		unlock_buffer(sbi->s_sbh);
 		mutex_unlock(&sbi->s_orphan_lock);
 		err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
 	} else {
 		struct ext4_iloc iloc2;
 		struct inode *i_prev =
 			&list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;

 		jbd_debug(4, "orphan inode %lu will point to %u\n",
 			  i_prev->i_ino, ino_next);
 		err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
 		if (err) {
 			mutex_unlock(&sbi->s_orphan_lock);
 			goto out_brelse;
 		}
 		NEXT_ORPHAN(i_prev) = ino_next;
 		err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
 		mutex_unlock(&sbi->s_orphan_lock);
 	}
 	if (err)
 		goto out_brelse;
 	NEXT_ORPHAN(inode) = 0;
 	err = ext4_mark_iloc_dirty(handle, inode, &iloc);
 out_err:
 	ext4_std_error(inode->i_sb, err);
 	return err;

 out_brelse:
 	brelse(iloc.bh);
 	goto out_err;
 }

 #ifdef CONFIG_QUOTA
 static int ext4_quota_on_mount(struct super_block *sb, int type)
 {
 	return dquot_quota_on_mount(sb,
 		rcu_dereference_protected(EXT4_SB(sb)->s_qf_names[type],
 					  lockdep_is_held(&sb->s_umount)),
 		EXT4_SB(sb)->s_jquota_fmt, type);
 }
 #endif

 static void ext4_process_orphan(struct inode *inode,
 				int *nr_truncates, int *nr_orphans)
 {
 	struct super_block *sb = inode->i_sb;
 	int ret;

 	dquot_initialize(inode);
 	if (inode->i_nlink) {
 		if (test_opt(sb, DEBUG))
 			ext4_msg(sb, KERN_DEBUG,
 				"%s: truncating inode %lu to %lld bytes",
 				__func__, inode->i_ino, inode->i_size);
 		jbd_debug(2, "truncating inode %lu to %lld bytes\n",
 			  inode->i_ino, inode->i_size);
 		inode_lock(inode);
 		truncate_inode_pages(inode->i_mapping, inode->i_size);
 		ret = ext4_truncate(inode);
 		if (ret) {
 			/*
 			 * We need to clean up the in-core orphan list
 			 * manually if ext4_truncate() failed to get a
 			 * transaction handle.
 			 */
 			ext4_orphan_del(NULL, inode);
 			ext4_std_error(inode->i_sb, ret);
 		}
 		inode_unlock(inode);
 		(*nr_truncates)++;
 	} else {
 		if (test_opt(sb, DEBUG))
 			ext4_msg(sb, KERN_DEBUG,
 				"%s: deleting unreferenced inode %lu",
 				__func__, inode->i_ino);
 		jbd_debug(2, "deleting unreferenced inode %lu\n",
 			  inode->i_ino);
 		(*nr_orphans)++;
 	}
 	iput(inode);  /* The delete magic happens here! */
 }

 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
  * the superblock) which were deleted from all directories, but held open by
  * a process at the time of a crash.  We walk the list and try to delete these
  * inodes at recovery time (only with a read-write filesystem).
  *
  * In order to keep the orphan inode chain consistent during traversal (in
  * case of crash during recovery), we link each inode into the superblock
  * orphan list_head and handle it the same way as an inode deletion during
  * normal operation (which journals the operations for us).
  *
  * We only do an iget() and an iput() on each inode, which is very safe if we
  * accidentally point at an in-use or already deleted inode.  The worst that
  * can happen in this case is that we get a "bit already cleared" message from
  * ext4_free_inode().  The only reason we would point at a wrong inode is if
  * e2fsck was run on this filesystem, and it must have already done the orphan
  * inode cleanup for us, so we can safely abort without any further action.
  */
 void ext4_orphan_cleanup(struct super_block *sb, struct ext4_super_block *es)
 {
 	unsigned int s_flags = sb->s_flags;
 	int nr_orphans = 0, nr_truncates = 0;
 	struct inode *inode;
 	int i, j;
 #ifdef CONFIG_QUOTA
 	int quota_update = 0;
 #endif
 	__le32 *bdata;
 	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);

 	if (!es->s_last_orphan && !oi->of_blocks) {
 		jbd_debug(4, "no orphan inodes to clean up\n");
 		return;
 	}

 	if (bdev_read_only(sb->s_bdev)) {
 		ext4_msg(sb, KERN_ERR, "write access "
 			"unavailable, skipping orphan cleanup");
 		return;
 	}

 	/* Check if feature set would not allow a r/w mount */
 	if (!ext4_feature_set_ok(sb, 0)) {
 		ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
 			 "unknown ROCOMPAT features");
 		return;
 	}

 	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
 		/* don't clear list on RO mount w/ errors */
 		if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
 			ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
 				  "clearing orphan list.\n");
 			es->s_last_orphan = 0;
 		}
 		jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
 		return;
 	}

 	if (s_flags & SB_RDONLY) {
 		ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
 		sb->s_flags &= ~SB_RDONLY;
 	}
 #ifdef CONFIG_QUOTA
 	/*
 	 * Turn on quotas which were not enabled for read-only mounts if
 	 * filesystem has quota feature, so that they are updated correctly.
 	 */
 	if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
 		int ret = ext4_enable_quotas(sb);

 		if (!ret)
 			quota_update = 1;
 		else
 			ext4_msg(sb, KERN_ERR,
 				"Cannot turn on quotas: error %d", ret);
 	}

 	/* Turn on journaled quotas used for old sytle */
 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
 		if (EXT4_SB(sb)->s_qf_names[i]) {
 			int ret = ext4_quota_on_mount(sb, i);

 			if (!ret)
 				quota_update = 1;
 			else
 				ext4_msg(sb, KERN_ERR,
 					"Cannot turn on journaled "
 					"quota: type %d: error %d", i, ret);
 		}
 	}
 #endif

 	while (es->s_last_orphan) {
 		/*
 		 * We may have encountered an error during cleanup; if
 		 * so, skip the rest.
 		 */
 		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
 			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
 			es->s_last_orphan = 0;
 			break;
 		}

 		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
 		if (IS_ERR(inode)) {
 			es->s_last_orphan = 0;
 			break;
 		}

 		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
 		ext4_process_orphan(inode, &nr_truncates, &nr_orphans);
 	}

 	for (i = 0; i < oi->of_blocks; i++) {
 		bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
 		for (j = 0; j < inodes_per_ob; j++) {
 			if (!bdata[j])
 				continue;
 			inode = ext4_orphan_get(sb, le32_to_cpu(bdata[j]));
 			if (IS_ERR(inode))
 				continue;
 			ext4_set_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
 			EXT4_I(inode)->i_orphan_idx = i * inodes_per_ob + j;
 			ext4_process_orphan(inode, &nr_truncates, &nr_orphans);
 		}
 	}

 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"

 	if (nr_orphans)
 		ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
 		       PLURAL(nr_orphans));
 	if (nr_truncates)
 		ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
 		       PLURAL(nr_truncates));
 #ifdef CONFIG_QUOTA
 	/* Turn off quotas if they were enabled for orphan cleanup */
 	if (quota_update) {
 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
 			if (sb_dqopt(sb)->files[i])
 				dquot_quota_off(sb, i);
 		}
 	}
 #endif
 	sb->s_flags = s_flags; /* Restore SB_RDONLY status */
 }

 void ext4_release_orphan_info(struct super_block *sb)
 {
 	int i;
 	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;

 	if (!oi->of_blocks)
 		return;
 	for (i = 0; i < oi->of_blocks; i++)
 		brelse(oi->of_binfo[i].ob_bh);
 	kfree(oi->of_binfo);
 }

 static struct ext4_orphan_block_tail *ext4_orphan_block_tail(
 						struct super_block *sb,
 						struct buffer_head *bh)
 {
 	return (struct ext4_orphan_block_tail *)(bh->b_data + sb->s_blocksize -
 				sizeof(struct ext4_orphan_block_tail));
 }

 static int ext4_orphan_file_block_csum_verify(struct super_block *sb,
 					      struct buffer_head *bh)
 {
 	__u32 calculated;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
 	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
 	struct ext4_orphan_block_tail *ot;
 	__le64 dsk_block_nr = cpu_to_le64(bh->b_blocknr);

 	if (!ext4_has_metadata_csum(sb))
 		return 1;

 	ot = ext4_orphan_block_tail(sb, bh);
 	calculated = ext4_chksum(EXT4_SB(sb), oi->of_csum_seed,
 				 (__u8 *)&dsk_block_nr, sizeof(dsk_block_nr));
 	calculated = ext4_chksum(EXT4_SB(sb), calculated, (__u8 *)bh->b_data,
 				 inodes_per_ob * sizeof(__u32));
 	return le32_to_cpu(ot->ob_checksum) == calculated;
 }

 /* This gets called only when checksumming is enabled */
 void ext4_orphan_file_block_trigger(struct jbd2_buffer_trigger_type *triggers,
 				    struct buffer_head *bh,
 				    void *data, size_t size)
 {
 	struct super_block *sb = EXT4_TRIGGER(triggers)->sb;
 	__u32 csum;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
 	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
 	struct ext4_orphan_block_tail *ot;
 	__le64 dsk_block_nr = cpu_to_le64(bh->b_blocknr);

 	csum = ext4_chksum(EXT4_SB(sb), oi->of_csum_seed,
 			   (__u8 *)&dsk_block_nr, sizeof(dsk_block_nr));
 	csum = ext4_chksum(EXT4_SB(sb), csum, (__u8 *)data,
 			   inodes_per_ob * sizeof(__u32));
 	ot = ext4_orphan_block_tail(sb, bh);
 	ot->ob_checksum = cpu_to_le32(csum);
 }

 int ext4_init_orphan_info(struct super_block *sb)
 {
 	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
 	struct inode *inode;
 	int i, j;
 	int ret;
 	int free;
 	__le32 *bdata;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
 	struct ext4_orphan_block_tail *ot;
 	ino_t orphan_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_orphan_file_inum);

 	if (!ext4_has_feature_orphan_file(sb))
 		return 0;

 	inode = ext4_iget(sb, orphan_ino, EXT4_IGET_SPECIAL);
 	if (IS_ERR(inode)) {
 		ext4_msg(sb, KERN_ERR, "get orphan inode failed");
 		return PTR_ERR(inode);
 	}
 	oi->of_blocks = inode->i_size >> sb->s_blocksize_bits;
 	oi->of_csum_seed = EXT4_I(inode)->i_csum_seed;
 	oi->of_binfo = kmalloc(oi->of_blocks*sizeof(struct ext4_orphan_block),
 			       GFP_KERNEL);
 	if (!oi->of_binfo) {
 		ret = -ENOMEM;
 		goto out_put;
 	}
 	for (i = 0; i < oi->of_blocks; i++) {
 		oi->of_binfo[i].ob_bh = ext4_bread(NULL, inode, i, 0);
 		if (IS_ERR(oi->of_binfo[i].ob_bh)) {
 			ret = PTR_ERR(oi->of_binfo[i].ob_bh);
 			goto out_free;
 		}
 		if (!oi->of_binfo[i].ob_bh) {
 			ret = -EIO;
 			goto out_free;
 		}
 		ot = ext4_orphan_block_tail(sb, oi->of_binfo[i].ob_bh);
 		if (le32_to_cpu(ot->ob_magic) != EXT4_ORPHAN_BLOCK_MAGIC) {
 			ext4_error(sb, "orphan file block %d: bad magic", i);
 			ret = -EIO;
 			goto out_free;
 		}
 		if (!ext4_orphan_file_block_csum_verify(sb,
 						oi->of_binfo[i].ob_bh)) {
 			ext4_error(sb, "orphan file block %d: bad checksum", i);
 			ret = -EIO;
 			goto out_free;
 		}
 		bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
 		free = 0;
 		for (j = 0; j < inodes_per_ob; j++)
 			if (bdata[j] == 0)
 				free++;
 		atomic_set(&oi->of_binfo[i].ob_free_entries, free);
 	}
 	iput(inode);
 	return 0;
 out_free:
 	for (i--; i >= 0; i--)
 		brelse(oi->of_binfo[i].ob_bh);
 	kfree(oi->of_binfo);
 out_put:
 	iput(inode);
 	return ret;
 }

 int ext4_orphan_file_empty(struct super_block *sb)
 {
 	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
 	int i;
 	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);

 	if (!ext4_has_feature_orphan_file(sb))
 		return 1;
 	for (i = 0; i < oi->of_blocks; i++)
 		if (atomic_read(&oi->of_binfo[i].ob_free_entries) !=
 		    inodes_per_ob)
 			return 0;
 	return 1;
 }
	/*
	* Ext4 orphan inode handling
	*/
	#include <linux/fs.h>
	#include <linux/quotaops.h>
	#include <linux/buffer_head.h>

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

	static int ext4_orphan_file_add(handle_t handle, struct inode inode)
	{
	int i, j, start;
	struct ext4_orphan_info *oi = &EXT4_SB(inode->i_sb)->s_orphan_info;
	int ret = 0;
	bool found = false;
	__le32 *bdata;
	int inodes_per_ob = ext4_inodes_per_orphan_block(inode->i_sb);
	int looped = 0;

	/*
	* Find block with free orphan entry. Use CPU number for a naive hash
	* for a search start in the orphan file
	*/
	start = raw_smp_processor_id()*13 % oi->of_blocks;
	i = start;
	do {
	if (atomic_dec_if_positive(&oi->of_binfo[i].ob_free_entries)
	>= 0) {
	found = true;
	break;
	}
	if (++i >= oi->of_blocks)
	i = 0;
	} while (i != start);

	if (!found) {
	/*
	* For now we don't grow or shrink orphan file. We just use
	* whatever was allocated at mke2fs time. The additional
	* credits we would have to reserve for each orphan inode
	* operation just don't seem worth it.
	*/
	return -ENOSPC;
	}

	ret = ext4_journal_get_write_access(handle, inode->i_sb,
	oi->of_binfo[i].ob_bh, EXT4_JTR_ORPHAN_FILE);
	if (ret) {
	atomic_inc(&oi->of_binfo[i].ob_free_entries);
	return ret;
	}

	bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
	/* Find empty slot in a block */
	j = 0;
	do {
	if (looped) {
	/*
	* Did we walk through the block several times without
	* finding free entry? It is theoretically possible
	* if entries get constantly allocated and freed or
	* if the block is corrupted. Avoid indefinite looping
	* and bail. We'll use orphan list instead.
	*/
	if (looped > 3) {
	atomic_inc(&oi->of_binfo[i].ob_free_entries);
	return -ENOSPC;
	}
	cond_resched();
	}
	while (bdata[j]) {
	if (++j >= inodes_per_ob) {
	j = 0;
	looped++;
	}
	}
	} while (cmpxchg(&bdata[j], (__le32)0, cpu_to_le32(inode->i_ino)) !=
	(__le32)0);

	EXT4_I(inode)->i_orphan_idx = i * inodes_per_ob + j;
	ext4_set_inode_state(inode, EXT4_STATE_ORPHAN_FILE);

	return ext4_handle_dirty_metadata(handle, NULL, oi->of_binfo[i].ob_bh);
	}

	/*
	* ext4_orphan_add() links an unlinked or truncated inode into a list of
	* such inodes, starting at the superblock, in case we crash before the
	* file is closed/deleted, or in case the inode truncate spans multiple
	* transactions and the last transaction is not recovered after a crash.
	*
	* At filesystem recovery time, we walk this list deleting unlinked
	* inodes and truncating linked inodes in ext4_orphan_cleanup().
	*
	* Orphan list manipulation functions must be called under i_rwsem unless
	* we are just creating the inode or deleting it.
	*/
	int ext4_orphan_add(handle_t handle, struct inode inode)
	{
	struct super_block *sb = inode->i_sb;
	struct ext4_sb_info *sbi = EXT4_SB(sb);
	struct ext4_iloc iloc;
	int err = 0, rc;
	bool dirty = false;

	if (!sbi->s_journal \|\| is_bad_inode(inode))
	return 0;

	WARN_ON_ONCE(!(inode->i_state & (I_NEW \| I_FREEING)) &&
	!inode_is_locked(inode));
	/*
	* Inode orphaned in orphan file or in orphan list?
	*/
	if (ext4_test_inode_state(inode, EXT4_STATE_ORPHAN_FILE) \|\|
	!list_empty(&EXT4_I(inode)->i_orphan))
	return 0;

	/*
	* Orphan handling is only valid for files with data blocks
	* being truncated, or files being unlinked. Note that we either
	* hold i_rwsem, or the inode can not be referenced from outside,
	* so i_nlink should not be bumped due to race
	*/
	ASSERT((S_ISREG(inode->i_mode) \|\| S_ISDIR(inode->i_mode) \|\|
	S_ISLNK(inode->i_mode)) \|\| inode->i_nlink == 0);

	if (sbi->s_orphan_info.of_blocks) {
	err = ext4_orphan_file_add(handle, inode);
	/*
	* Fallback to normal orphan list of orphan file is
	* out of space
	*/
	if (err != -ENOSPC)
	return err;
	}

	BUFFER_TRACE(sbi->s_sbh, "get_write_access");
	err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh,
	EXT4_JTR_NONE);
	if (err)
	goto out;

	err = ext4_reserve_inode_write(handle, inode, &iloc);
	if (err)
	goto out;

	mutex_lock(&sbi->s_orphan_lock);
	/*
	* Due to previous errors inode may be already a part of on-disk
	* orphan list. If so skip on-disk list modification.
	*/
	if (!NEXT_ORPHAN(inode) \|\| NEXT_ORPHAN(inode) >
	(le32_to_cpu(sbi->s_es->s_inodes_count))) {
	/* Insert this inode at the head of the on-disk orphan list */
	NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
	lock_buffer(sbi->s_sbh);
	sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
	ext4_superblock_csum_set(sb);
	unlock_buffer(sbi->s_sbh);
	dirty = true;
	}
	list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
	mutex_unlock(&sbi->s_orphan_lock);

	if (dirty) {
	err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
	rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
	if (!err)
	err = rc;
	if (err) {
	/*
	* We have to remove inode from in-memory list if
	* addition to on disk orphan list failed. Stray orphan
	* list entries can cause panics at unmount time.
	*/
	mutex_lock(&sbi->s_orphan_lock);
	list_del_init(&EXT4_I(inode)->i_orphan);
	mutex_unlock(&sbi->s_orphan_lock);
	}
	} else
	brelse(iloc.bh);

	jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
	jbd_debug(4, "orphan inode %lu will point to %d\n",
	inode->i_ino, NEXT_ORPHAN(inode));
	out:
	ext4_std_error(sb, err);
	return err;
	}

	static int ext4_orphan_file_del(handle_t handle, struct inode inode)
	{
	struct ext4_orphan_info *oi = &EXT4_SB(inode->i_sb)->s_orphan_info;
	__le32 *bdata;
	int blk, off;
	int inodes_per_ob = ext4_inodes_per_orphan_block(inode->i_sb);
	int ret = 0;

	if (!handle)
	goto out;
	blk = EXT4_I(inode)->i_orphan_idx / inodes_per_ob;
	off = EXT4_I(inode)->i_orphan_idx % inodes_per_ob;
	if (WARN_ON_ONCE(blk >= oi->of_blocks))
	goto out;

	ret = ext4_journal_get_write_access(handle, inode->i_sb,
	oi->of_binfo[blk].ob_bh, EXT4_JTR_ORPHAN_FILE);
	if (ret)
	goto out;

	bdata = (__le32 *)(oi->of_binfo[blk].ob_bh->b_data);
	bdata[off] = 0;
	atomic_inc(&oi->of_binfo[blk].ob_free_entries);
	ret = ext4_handle_dirty_metadata(handle, NULL, oi->of_binfo[blk].ob_bh);
	out:
	ext4_clear_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
	INIT_LIST_HEAD(&EXT4_I(inode)->i_orphan);

	return ret;
	}

	/*
	* ext4_orphan_del() removes an unlinked or truncated inode from the list
	* of such inodes stored on disk, because it is finally being cleaned up.
	*/
	int ext4_orphan_del(handle_t handle, struct inode inode)
	{
	struct list_head *prev;
	struct ext4_inode_info *ei = EXT4_I(inode);
	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
	__u32 ino_next;
	struct ext4_iloc iloc;
	int err = 0;

	if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
	return 0;

	WARN_ON_ONCE(!(inode->i_state & (I_NEW \| I_FREEING)) &&
	!inode_is_locked(inode));
	if (ext4_test_inode_state(inode, EXT4_STATE_ORPHAN_FILE))
	return ext4_orphan_file_del(handle, inode);

	/* Do this quick check before taking global s_orphan_lock. */
	if (list_empty(&ei->i_orphan))
	return 0;

	if (handle) {
	/* Grab inode buffer early before taking global s_orphan_lock */
	err = ext4_reserve_inode_write(handle, inode, &iloc);
	}

	mutex_lock(&sbi->s_orphan_lock);
	jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);

	prev = ei->i_orphan.prev;
	list_del_init(&ei->i_orphan);

	/* If we're on an error path, we may not have a valid
	* transaction handle with which to update the orphan list on
	* disk, but we still need to remove the inode from the linked
	* list in memory. */
	if (!handle \|\| err) {
	mutex_unlock(&sbi->s_orphan_lock);
	goto out_err;
	}

	ino_next = NEXT_ORPHAN(inode);
	if (prev == &sbi->s_orphan) {
	jbd_debug(4, "superblock will point to %u\n", ino_next);
	BUFFER_TRACE(sbi->s_sbh, "get_write_access");
	err = ext4_journal_get_write_access(handle, inode->i_sb,
	sbi->s_sbh, EXT4_JTR_NONE);
	if (err) {
	mutex_unlock(&sbi->s_orphan_lock);
	goto out_brelse;
	}
	lock_buffer(sbi->s_sbh);
	sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
	ext4_superblock_csum_set(inode->i_sb);
	unlock_buffer(sbi->s_sbh);
	mutex_unlock(&sbi->s_orphan_lock);
	err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
	} else {
	struct ext4_iloc iloc2;
	struct inode *i_prev =
	&list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;

	jbd_debug(4, "orphan inode %lu will point to %u\n",
	i_prev->i_ino, ino_next);
	err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
	if (err) {
	mutex_unlock(&sbi->s_orphan_lock);
	goto out_brelse;
	}
	NEXT_ORPHAN(i_prev) = ino_next;
	err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
	mutex_unlock(&sbi->s_orphan_lock);
	}
	if (err)
	goto out_brelse;
	NEXT_ORPHAN(inode) = 0;
	err = ext4_mark_iloc_dirty(handle, inode, &iloc);
	out_err:
	ext4_std_error(inode->i_sb, err);
	return err;

	out_brelse:
	brelse(iloc.bh);
	goto out_err;
	}

	#ifdef CONFIG_QUOTA
	static int ext4_quota_on_mount(struct super_block *sb, int type)
	{
	return dquot_quota_on_mount(sb,
	rcu_dereference_protected(EXT4_SB(sb)->s_qf_names[type],
	lockdep_is_held(&sb->s_umount)),
	EXT4_SB(sb)->s_jquota_fmt, type);
	}
	#endif

	static void ext4_process_orphan(struct inode *inode,
	int nr_truncates, int nr_orphans)
	{
	struct super_block *sb = inode->i_sb;
	int ret;

	dquot_initialize(inode);
	if (inode->i_nlink) {
	if (test_opt(sb, DEBUG))
	ext4_msg(sb, KERN_DEBUG,
	"%s: truncating inode %lu to %lld bytes",
	__func__, inode->i_ino, inode->i_size);
	jbd_debug(2, "truncating inode %lu to %lld bytes\n",
	inode->i_ino, inode->i_size);
	inode_lock(inode);
	truncate_inode_pages(inode->i_mapping, inode->i_size);
	ret = ext4_truncate(inode);
	if (ret) {
	/*
	* We need to clean up the in-core orphan list
	* manually if ext4_truncate() failed to get a
	* transaction handle.
	*/
	ext4_orphan_del(NULL, inode);
	ext4_std_error(inode->i_sb, ret);
	}
	inode_unlock(inode);
	(*nr_truncates)++;
	} else {
	if (test_opt(sb, DEBUG))
	ext4_msg(sb, KERN_DEBUG,
	"%s: deleting unreferenced inode %lu",
	__func__, inode->i_ino);
	jbd_debug(2, "deleting unreferenced inode %lu\n",
	inode->i_ino);
	(*nr_orphans)++;
	}
	iput(inode); /* The delete magic happens here! */
	}

	/* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
	* the superblock) which were deleted from all directories, but held open by
	* a process at the time of a crash. We walk the list and try to delete these
	* inodes at recovery time (only with a read-write filesystem).
	*
	* In order to keep the orphan inode chain consistent during traversal (in
	* case of crash during recovery), we link each inode into the superblock
	* orphan list_head and handle it the same way as an inode deletion during
	* normal operation (which journals the operations for us).
	*
	* We only do an iget() and an iput() on each inode, which is very safe if we
	* accidentally point at an in-use or already deleted inode. The worst that
	* can happen in this case is that we get a "bit already cleared" message from
	* ext4_free_inode(). The only reason we would point at a wrong inode is if
	* e2fsck was run on this filesystem, and it must have already done the orphan
	* inode cleanup for us, so we can safely abort without any further action.
	*/
	void ext4_orphan_cleanup(struct super_block sb, struct ext4_super_block es)
	{
	unsigned int s_flags = sb->s_flags;
	int nr_orphans = 0, nr_truncates = 0;
	struct inode *inode;
	int i, j;
	#ifdef CONFIG_QUOTA
	int quota_update = 0;
	#endif
	__le32 *bdata;
	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);

	if (!es->s_last_orphan && !oi->of_blocks) {
	jbd_debug(4, "no orphan inodes to clean up\n");
	return;
	}

	if (bdev_read_only(sb->s_bdev)) {
	ext4_msg(sb, KERN_ERR, "write access "
	"unavailable, skipping orphan cleanup");
	return;
	}

	/* Check if feature set would not allow a r/w mount */
	if (!ext4_feature_set_ok(sb, 0)) {
	ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
	"unknown ROCOMPAT features");
	return;
	}

	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
	/* don't clear list on RO mount w/ errors */
	if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
	ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
	"clearing orphan list.\n");
	es->s_last_orphan = 0;
	}
	jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
	return;
	}

	if (s_flags & SB_RDONLY) {
	ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
	sb->s_flags &= ~SB_RDONLY;
	}
	#ifdef CONFIG_QUOTA
	/*
	* Turn on quotas which were not enabled for read-only mounts if
	* filesystem has quota feature, so that they are updated correctly.
	*/
	if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
	int ret = ext4_enable_quotas(sb);

	if (!ret)
	quota_update = 1;
	else
	ext4_msg(sb, KERN_ERR,
	"Cannot turn on quotas: error %d", ret);
	}

	/* Turn on journaled quotas used for old sytle */
	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
	if (EXT4_SB(sb)->s_qf_names[i]) {
	int ret = ext4_quota_on_mount(sb, i);

	if (!ret)
	quota_update = 1;
	else
	ext4_msg(sb, KERN_ERR,
	"Cannot turn on journaled "
	"quota: type %d: error %d", i, ret);
	}
	}
	#endif

	while (es->s_last_orphan) {
	/*
	* We may have encountered an error during cleanup; if
	* so, skip the rest.
	*/
	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
	jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
	es->s_last_orphan = 0;
	break;
	}

	inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
	if (IS_ERR(inode)) {
	es->s_last_orphan = 0;
	break;
	}

	list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
	ext4_process_orphan(inode, &nr_truncates, &nr_orphans);
	}

	for (i = 0; i < oi->of_blocks; i++) {
	bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
	for (j = 0; j < inodes_per_ob; j++) {
	if (!bdata[j])
	continue;
	inode = ext4_orphan_get(sb, le32_to_cpu(bdata[j]));
	if (IS_ERR(inode))
	continue;
	ext4_set_inode_state(inode, EXT4_STATE_ORPHAN_FILE);
	EXT4_I(inode)->i_orphan_idx = i * inodes_per_ob + j;
	ext4_process_orphan(inode, &nr_truncates, &nr_orphans);
	}
	}

	#define PLURAL(x) (x), ((x) == 1) ? "" : "s"

	if (nr_orphans)
	ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
	PLURAL(nr_orphans));
	if (nr_truncates)
	ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
	PLURAL(nr_truncates));
	#ifdef CONFIG_QUOTA
	/* Turn off quotas if they were enabled for orphan cleanup */
	if (quota_update) {
	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
	if (sb_dqopt(sb)->files[i])
	dquot_quota_off(sb, i);
	}
	}
	#endif
	sb->s_flags = s_flags; /* Restore SB_RDONLY status */
	}

	void ext4_release_orphan_info(struct super_block *sb)
	{
	int i;
	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;

	if (!oi->of_blocks)
	return;
	for (i = 0; i < oi->of_blocks; i++)
	brelse(oi->of_binfo[i].ob_bh);
	kfree(oi->of_binfo);
	}

	static struct ext4_orphan_block_tail *ext4_orphan_block_tail(
	struct super_block *sb,
	struct buffer_head *bh)
	{
	return (struct ext4_orphan_block_tail *)(bh->b_data + sb->s_blocksize -
	sizeof(struct ext4_orphan_block_tail));
	}

	static int ext4_orphan_file_block_csum_verify(struct super_block *sb,
	struct buffer_head *bh)
	{
	__u32 calculated;
	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
	struct ext4_orphan_block_tail *ot;
	__le64 dsk_block_nr = cpu_to_le64(bh->b_blocknr);

	if (!ext4_has_metadata_csum(sb))
	return 1;

	ot = ext4_orphan_block_tail(sb, bh);
	calculated = ext4_chksum(EXT4_SB(sb), oi->of_csum_seed,
	(__u8 *)&dsk_block_nr, sizeof(dsk_block_nr));
	calculated = ext4_chksum(EXT4_SB(sb), calculated, (__u8 *)bh->b_data,
	inodes_per_ob * sizeof(__u32));
	return le32_to_cpu(ot->ob_checksum) == calculated;
	}

	/* This gets called only when checksumming is enabled */
	void ext4_orphan_file_block_trigger(struct jbd2_buffer_trigger_type *triggers,
	struct buffer_head *bh,
	void *data, size_t size)
	{
	struct super_block *sb = EXT4_TRIGGER(triggers)->sb;
	__u32 csum;
	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
	struct ext4_orphan_block_tail *ot;
	__le64 dsk_block_nr = cpu_to_le64(bh->b_blocknr);

	csum = ext4_chksum(EXT4_SB(sb), oi->of_csum_seed,
	(__u8 *)&dsk_block_nr, sizeof(dsk_block_nr));
	csum = ext4_chksum(EXT4_SB(sb), csum, (__u8 *)data,
	inodes_per_ob * sizeof(__u32));
	ot = ext4_orphan_block_tail(sb, bh);
	ot->ob_checksum = cpu_to_le32(csum);
	}

	int ext4_init_orphan_info(struct super_block *sb)
	{
	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
	struct inode *inode;
	int i, j;
	int ret;
	int free;
	__le32 *bdata;
	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);
	struct ext4_orphan_block_tail *ot;
	ino_t orphan_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_orphan_file_inum);

	if (!ext4_has_feature_orphan_file(sb))
	return 0;

	inode = ext4_iget(sb, orphan_ino, EXT4_IGET_SPECIAL);
	if (IS_ERR(inode)) {
	ext4_msg(sb, KERN_ERR, "get orphan inode failed");
	return PTR_ERR(inode);
	}
	oi->of_blocks = inode->i_size >> sb->s_blocksize_bits;
	oi->of_csum_seed = EXT4_I(inode)->i_csum_seed;
	oi->of_binfo = kmalloc(oi->of_blocks*sizeof(struct ext4_orphan_block),
	GFP_KERNEL);
	if (!oi->of_binfo) {
	ret = -ENOMEM;
	goto out_put;
	}
	for (i = 0; i < oi->of_blocks; i++) {
	oi->of_binfo[i].ob_bh = ext4_bread(NULL, inode, i, 0);
	if (IS_ERR(oi->of_binfo[i].ob_bh)) {
	ret = PTR_ERR(oi->of_binfo[i].ob_bh);
	goto out_free;
	}
	if (!oi->of_binfo[i].ob_bh) {
	ret = -EIO;
	goto out_free;
	}
	ot = ext4_orphan_block_tail(sb, oi->of_binfo[i].ob_bh);
	if (le32_to_cpu(ot->ob_magic) != EXT4_ORPHAN_BLOCK_MAGIC) {
	ext4_error(sb, "orphan file block %d: bad magic", i);
	ret = -EIO;
	goto out_free;
	}
	if (!ext4_orphan_file_block_csum_verify(sb,
	oi->of_binfo[i].ob_bh)) {
	ext4_error(sb, "orphan file block %d: bad checksum", i);
	ret = -EIO;
	goto out_free;
	}
	bdata = (__le32 *)(oi->of_binfo[i].ob_bh->b_data);
	free = 0;
	for (j = 0; j < inodes_per_ob; j++)
	if (bdata[j] == 0)
	free++;
	atomic_set(&oi->of_binfo[i].ob_free_entries, free);
	}
	iput(inode);
	return 0;
	out_free:
	for (i--; i >= 0; i--)
	brelse(oi->of_binfo[i].ob_bh);
	kfree(oi->of_binfo);
	out_put:
	iput(inode);
	return ret;
	}

	int ext4_orphan_file_empty(struct super_block *sb)
	{
	struct ext4_orphan_info *oi = &EXT4_SB(sb)->s_orphan_info;
	int i;
	int inodes_per_ob = ext4_inodes_per_orphan_block(sb);

	if (!ext4_has_feature_orphan_file(sb))
	return 1;
	for (i = 0; i < oi->of_blocks; i++)
	if (atomic_read(&oi->of_binfo[i].ob_free_entries) !=
	inodes_per_ob)
	return 0;
	return 1;
	}