On Wed, 29 Nov 2017 18:50:22 +0000
"Dr. David Alan Gilbert (git)" <dgilb...@redhat.com> wrote:
> From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
>
> vhost_update_mem will replace the existing update mechanism.
> They make use of the Flatview we have now to make the update simpler.
> This commit just adds the basic structure.
see below suggestion on dropping vhost_region_add/vhost_region_del
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> hw/virtio/vhost.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 44 insertions(+)
>
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index 938253d1e8..c959a59fb3 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -629,6 +629,43 @@ static void vhost_begin(MemoryListener *listener)
> dev->mem_changed_start_addr = -1;
> }
>
> +struct vhost_update_mem_tmp {
> + struct vhost_dev *dev;
> + uint32_t nregions;
> + struct vhost_memory_region *regions;
> +};
> +
> +/* Called for each MRS from vhost_update_mem */
> +static int vhost_update_mem_cb(MemoryRegionSection *mrs, void *opaque)
> +{
> + if (!vhost_section(mrs)) {
> + return 0;
> + }
> +
it's possible to move section tracking from vhost_region_add() to here
++dev->n_mem_sections;
dev->mem_sections = g_renew(MemoryRegionSection, dev->mem_sections,
dev->n_mem_sections);
;[dev->n_mem_sections - 1] = *section;
memory_region_ref(section->mr);
...
> +static int vhost_update_mem(struct vhost_dev *dev)
> +{
> + int res;
> + struct vhost_update_mem_tmp vtmp;
> + vtmp.regions = 0;
> + vtmp.nregions = 0;
> + vtmp.dev = dev;
iterate over dev->mem_sections
memory_region_unref(section->mr);
g_free(dev->mem_sections)
dev->mem_sections = NULL;
with this you won't need vhost_region_add/del callbacks anymore
> +
> + res = address_space_iterate(&address_space_memory,
> + vhost_update_mem_cb, &vtmp);
> + if (res) {
> + goto out;
> + }
> +
> + /* TODO */
> +out:
> + g_free(vtmp.regions);
> + return res;
> +}
> +
> static void vhost_commit(MemoryListener *listener)
> {
> struct vhost_dev *dev = container_of(listener, struct vhost_dev,
> @@ -648,6 +685,10 @@ static void vhost_commit(MemoryListener *listener)
> return;
> }
>
> + if (vhost_update_mem(dev)) {
> + return;
> + }
> +
> if (dev->started) {
> start_addr = dev->mem_changed_start_addr;
> size = dev->mem_changed_end_addr - dev->mem_changed_start_addr + 1;
> @@ -1523,6 +1564,9 @@ int vhost_dev_start(struct vhost_dev *hdev,
> VirtIODevice *vdev)
> goto fail_features;
> }
>
> + if (vhost_update_mem(hdev)) {
> + goto fail_mem;
> + }
> if (vhost_dev_has_iommu(hdev)) {
> memory_listener_register(&hdev->iommu_listener, vdev->dma_as);
> }
