ext4: fix error handling in migrate

Set i_nlink to zero for temporary inode from very beginning.
otherwise we may fail to start new journal handle and this
inode will be unreferenced but with i_nlink == 1
Since we hold inode reference it can not be pruned.

Also add missed journal_start retval check.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Dmitry Monakhov 2010-03-01 23:14:36 -05:00 коммит произвёл Theodore Ts'o
Родитель 437ca0fda3
Коммит f39490bcd1
1 изменённых файлов: 14 добавлений и 15 удалений

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@ -503,14 +503,10 @@ int ext4_ext_migrate(struct inode *inode)
}
i_size_write(tmp_inode, i_size_read(inode));
/*
* We don't want the inode to be reclaimed
* if we got interrupted in between. We have
* this tmp inode carrying reference to the
* data blocks of the original file. We set
* the i_nlink to zero at the last stage after
* switching the original file to extent format
* Set the i_nlink to zero so it will be deleted later
* when we drop inode reference.
*/
tmp_inode->i_nlink = 1;
tmp_inode->i_nlink = 0;
ext4_ext_tree_init(handle, tmp_inode);
ext4_orphan_add(handle, tmp_inode);
@ -537,6 +533,16 @@ int ext4_ext_migrate(struct inode *inode)
up_read((&EXT4_I(inode)->i_data_sem));
handle = ext4_journal_start(inode, 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;
@ -618,15 +624,8 @@ err_out:
/* Reset the extent details */
ext4_ext_tree_init(handle, tmp_inode);
/*
* Set the i_nlink to zero so that
* generic_drop_inode really deletes the
* inode
*/
tmp_inode->i_nlink = 0;
ext4_journal_stop(handle);
out:
unlock_new_inode(tmp_inode);
iput(tmp_inode);