ocfs2: drop acl cache for directories too

ocfs2_data_convert_worker() is currently dropping any cached acl info
for FILE before down-converting meta lock. It should also drop for
DIRECTORY. Otherwise the second acl lookup returns the cached one (from
VFS layer) which could be already stale.

The problem we are seeing is that the acl changes on one node doesn't
get refreshed on other nodes in the following case:

Node 1 Node 2
-------------- ----------------
getfacl dir1

getfacl dir1 <-- this is OK

setfacl -m u:user1:rwX dir1
getfacl dir1 <-- see the change for user1

getfacl dir1 <-- can't see change for user1

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Wengang Wang <[e-mail]>
Reviewed-by: Joseph Qi <[e-mail]>
Cc: Mark Fasheh <[e-mail]>
Cc: Joel Becker <[e-mail]>
Cc: Junxiao Bi <[e-mail]>
Cc: Changwei Ge <[e-mail]>
Cc: Gang He <[e-mail]>
Cc: Jun Piao <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/ocfs2/dlmglue.c

···
 		oi = OCFS2_I(inode);
 		oi->ip_dir_lock_gen++;
 		mlog(0, "generation: %u\n", oi->ip_dir_lock_gen);
-		goto out;
+		goto out_forget;
 	}
 
 	if (!S_ISREG(inode->i_mode))
···
 		filemap_fdatawait(mapping);
 	}
 
+out_forget:
 	forget_all_cached_acls(inode);
 
 out: