BITMAP_IO_QUEUED
if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags))
clear_bit(BITMAP_IO_QUEUED, &device->flags);
D_ASSERT(device, !test_bit(BITMAP_IO_QUEUED, &device->flags));
if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags))