vfio_lock_acct
vfio_lock_acct(dma, -unlocked, true);
vfio_lock_acct(dma, locked - unlocked, true);
ret = vfio_lock_acct(dma, lock_acct, false);
vfio_lock_acct(dma, locked - unlocked, true);
ret = vfio_lock_acct(dma, 1, false);
vfio_lock_acct(dma, -unlocked, true);
vfio_lock_acct(dma, -1, true);