Mark Fasheh wrote: > In order to protect against mmap changing the inline data state, you should > hold a write lock on ip_alloc_sem across the call to ocfs2_xattr_ibody_find() > and until the return from ocfs2_xattr_set_entry. > > So basically, ocfs2_xattr_set() should look like: > > ... > down_write(&oi->ip_alloc_sem); > ocfs2_ibody_find(); > ... > ocfs2_xattr_set_entry(); > up_write(&oi->ip_alloc_sem); > ... > > This way mmap can't change inline data state in between the calls to > ibody_find and xattr_set_entry.
Thanks the guide. I think I have done what your said. In ocfs2_ibody_find(), I checked the l_count/id_count with readable semaphore. And in ocfs2_xattr_set_ibody, I checked it again and follow by ocfs2_xattr_set_entry() with writable semaphore. If mmap change l_count/id_count between those two function, I still have chance to know it. And data in struct ocfs2_xattr_search which filled in ocfs2_ibody_find() are not affected by mmap operations. Best regards, tiger _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
