> > Take this example: > > > > fd = open() > > addr = mmap(.., fd) > > write(fd, ...) > > close(fd) > > sleep(100) > > msync(addr,...) > > munmap(addr) > > > > The file times will be updated in write(), but with your patch, the > > bit in the mapping will also be set. > > > > Then in msync() the file times will be updated again, which is wrong, > > since the memory was _not_ modified through the mapping. > > This is correct. I have updated my proposed patch to include the clearing > of AS_MCTIME in the routine which updates the mtime field. That doesn't really help. Look at __generic_file_aio_write_nolock(). file_update_time() is called before the data is written, so after the last write, there will be nothing to clear the flag. And even if fixed this case by moving the file_update_time() call to the end of the function, there's no guarantee, that some filesystem won't do something exotic and call set_page_dirty() indenpendently of write(). Good luck auditing all the set_page_dirty() calls ;) Thanks, Miklos - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
