4 fixes, based on 422ce5a97570cb8a37d016b6bc2021ae4dac5499:

Subject: ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang
Subject: ocfs2: fix posix_acl_create deadlock
Subject: ksm: fix conflict between mmput and scan_get_next_rmap_item
Subject: mm: thp: calculate the mapcount correctly for THP pages during WP faults