HelenOS sources
pio_write_le64 197 uspace/drv/block/virtio-blk/virtio-blk.c pio_write_le64(&req_header->sector, ba);
pio_write_le64 101 uspace/lib/virtio/virtio.c pio_write_le64(&d->addr, addr);
pio_write_le64 267 uspace/lib/virtio/virtio.c pio_write_le64(&cfg->queue_desc, q->phys);
pio_write_le64 268 uspace/lib/virtio/virtio.c pio_write_le64(&cfg->queue_avail, q->phys + avail_offset);
pio_write_le64 269 uspace/lib/virtio/virtio.c pio_write_le64(&cfg->queue_used, q->phys + used_offset);
HelenOS homepage, sources at GitHub