static int virtio_mem_sbm_plug_any_sb()

in virtio_mem.c [1653:1692]

• 33 lines of code
• 10 McCabe index (conditional complexity)

static int virtio_mem_sbm_plug_any_sb(struct virtio_mem *vm,
				      unsigned long mb_id, uint64_t *nb_sb)
{
	const int old_state = virtio_mem_sbm_get_mb_state(vm, mb_id);
	unsigned long pfn, nr_pages;
	int sb_id, count;
	int rc;

	if (WARN_ON_ONCE(!*nb_sb))
		return -EINVAL;

	while (*nb_sb) {
		sb_id = virtio_mem_sbm_first_unplugged_sb(vm, mb_id);
		if (sb_id >= vm->sbm.sbs_per_mb)
			break;
		count = 1;
		while (count < *nb_sb &&
		       sb_id + count < vm->sbm.sbs_per_mb &&
		       !virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id + count, 1))
			count++;

		rc = virtio_mem_sbm_plug_sb(vm, mb_id, sb_id, count);
		if (rc)
			return rc;
		*nb_sb -= count;
		if (old_state == VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL)
			continue;

		/* fake-online the pages if the memory block is online */
		pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) +
			       sb_id * vm->sbm.sb_size);
		nr_pages = PFN_DOWN(count * vm->sbm.sb_size);
		virtio_mem_fake_online(pfn, nr_pages);
	}

	if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb))
		virtio_mem_sbm_set_mb_state(vm, mb_id, old_state - 1);

	return 0;
}