static uint64_t ivshmem_io_read(void *opaque, hwaddr addr, unsigned size) { IVShmemState *s = opaque; uint32_t ret; switch (addr) { case INTRMASK: ret = ivshmem_IntrMask_read(s); break; case INTRSTATUS: ret = ivshmem_IntrStatus_read(s); break; case IVPOSITION: /* return my VM ID if the memory is mapped */ if (s->shm_fd >= 0) { ret = s->vm_id; } else { ret = -1; } break; default: IVSHMEM_DPRINTF("why are we reading " TARGET_FMT_plx "\n", addr); ret = 0; } return ret; }