Re: [Qemu-devel] [PATCH for-4.2 v10 08/15] virtio-iommu: Implement map/unmap

[Peter Xu]

On Tue, Jul 30, 2019 at 07:21:30PM +0200, Eric Auger wrote:

[...]

> +    mapping = g_tree_lookup(domain->mappings, (gpointer)(&interval));
> +
> +    while (mapping) {
> +        viommu_interval current;
> +        uint64_t low  = mapping->virt_addr;
> +        uint64_t high = mapping->virt_addr + mapping->size - 1;
> +
> +        current.low = low;
> +        current.high = high;
> +
> +        if (low == interval.low && size >= mapping->size) {
> +            g_tree_remove(domain->mappings, (gpointer)(&current));
> +            interval.low = high + 1;
> +            trace_virtio_iommu_unmap_left_interval(current.low, current.high,
> +                interval.low, interval.high);
> +        } else if (high == interval.high && size >= mapping->size) {
> +            trace_virtio_iommu_unmap_right_interval(current.low, 
> current.high,
> +                interval.low, interval.high);
> +            g_tree_remove(domain->mappings, (gpointer)(&current));
> +            interval.high = low - 1;
> +        } else if (low > interval.low && high < interval.high) {
> +            trace_virtio_iommu_unmap_inc_interval(current.low, current.high);
> +            g_tree_remove(domain->mappings, (gpointer)(&current));
> +        } else {
> +            break;
> +        }
> +        if (interval.low >= interval.high) {
> +            return VIRTIO_IOMMU_S_OK;
> +        } else {
> +            mapping = g_tree_lookup(domain->mappings, (gpointer)(&interval));
> +        }
> +    }
> +
> +    if (mapping) {
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "****** %s: Unmap 0x%"PRIx64" size=0x%"PRIx64
> +                     " from 0x%"PRIx64" size=0x%"PRIx64" is not supported\n",
> +                     __func__, interval.low, size,
> +                     mapping->virt_addr, mapping->size);
> +    } else {
> +        return VIRTIO_IOMMU_S_OK;
> +    }
> +
> +    return VIRTIO_IOMMU_S_INVAL;

Could the above chunk be simplified as something like below?

  while ((mapping = g_tree_lookup(domain->mappings, &interval))) {
    g_tree_remove(domain->mappings, mapping);
  }

Thanks,

-- 
Peter Xu