• Tyler Hicks's avatar
    vfs: Correctly set the dir i_mutex lockdep class · 978d6d8c
    Tyler Hicks authored
    9a7aa12f introduced additional logic around setting the i_mutex
    lockdep class for directory inodes. The idea was that some filesystems
    may want their own special lockdep class for different directory
    inodes and calling unlock_new_inode() should not clobber one of
    those special classes.
    
    I believe that the added conditional, around the *negated* return value
    of lockdep_match_class(), caused directory inodes to be placed in the
    wrong lockdep class.
    
    inode_init_always() sets the i_mutex lockdep class with i_mutex_key for
    all inodes. If the filesystem did not change the class during inode
    initialization, then the conditional mentioned above was false and the
    directory inode was incorrectly left in the non-directory lockdep class.
    If the filesystem did set a special lockdep class, then the conditional
    mentioned above was true and that class was clobbered with
    i_mutex_dir_key.
    
    This patch removes the negation from the conditional so that the i_mutex
    lockdep class is properly set for directory inodes. Special classes are
    preserved and directory inodes with unmodified classes are set with
    i_mutex_dir_key.
    Signed-off-by: default avatarTyler Hicks <tyhicks@canonical.com>
    Reviewed-by: default avatarJan Kara <jack@suse.cz>
    Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
    978d6d8c
inode.c 45.1 KB