tree d5027dc9645dea4a5536819ac98f4299757fff22
parent 7ad8e4e6ae2a7c95445ee1715b1714106fb95037
author Jan Kara <jack@suse.cz> 1304435578 -0400
committer Theodore Ts'o <tytso@mit.edu> 1304435578 -0400

ext4: fix deadlock in ext4_symlink() in ENOSPC conditions

ext4_symlink() cannot call __page_symlink() with transaction open.
__page_symlink() calls ext4_write_begin() which can wait for
transaction commit if we are running out of space thus causing a
deadlock. Also error recovery in ext4_truncate_failed_write() does not
count with the transaction being already started (although I'm not
aware of any particular deadlock here).

Fix the problem by stopping a transaction before calling
__page_symlink() (we have to be careful and put inode to orphan list
so that it gets deleted in case of crash) and starting another one
after __page_symlink() returns for addition of symlink into a
directory.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>