quota: Get rid of nested I_MUTEX_QUOTA locking subclass
authorJan Kara <jack@suse.cz>
Wed, 25 Apr 2012 19:15:53 +0000 (21:15 +0200)
committerJan Kara <jack@suse.cz>
Tue, 15 May 2012 21:34:39 +0000 (23:34 +0200)
commita80b12c3d08dbbf15e6a551e481c32a2df4911f3
tree364989f0fc990496820296b5fc6b655e29416c14
parentf9ef178412cab442719c9ffdc659933f5f2fa87e
quota: Get rid of nested I_MUTEX_QUOTA locking subclass

So far i_mutex was ranking above dqonoff_mutex and i_mutex on quota files
was special and ranking below dqonoff_mutex (and several other locks).
However there's no real need for i_mutex on quota files to be special.
IO on quota files is serialized by dqio_mutex anyway so we don't need to
take i_mutex when writing to quota files. Other places where we take i_mutex
on quota file can accomodate standard i_mutex lock ranking, we only need
to change the lock ranking to be dqonoff_mutex > i_mutex which is a matter
of changing documentation because there's no place which would enforce
ordering in the other direction.

Signed-off-by: Jan Kara <jack@suse.cz>
fs/quota/dquot.c