[v10,03/10] virtio-iommu: Add memory notifiers for map/unmap

From: Bharat Bhushan <bbhushan2@marvell.com>

Extend VIRTIO_IOMMU_T_MAP/UNMAP request to notify memory listeners. It
will call VFIO notifier to map/unmap regions in the physical IOMMU.

Signed-off-by: Bharat Bhushan <bbhushan2@marvell.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
v10:
* Use the flags from IOMMUMemoryRegion
* Pass virt_start/virt_end rather than size, to avoid dealing with
  overflow and for consistency.
---
 hw/virtio/virtio-iommu.c | 53 ++++++++++++++++++++++++++++++++++++++++
 hw/virtio/trace-events   |  2 ++
 2 files changed, 55 insertions(+)

Hi Jean,

On 10/8/20 7:15 PM, Jean-Philippe Brucker wrote:
> From: Bharat Bhushan <bbhushan2@marvell.com>
> 
> Extend VIRTIO_IOMMU_T_MAP/UNMAP request to notify memory listeners. It
> will call VFIO notifier to map/unmap regions in the physical IOMMU.
> 
> Signed-off-by: Bharat Bhushan <bbhushan2@marvell.com>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
> v10:
> * Use the flags from IOMMUMemoryRegion
> * Pass virt_start/virt_end rather than size, to avoid dealing with
>   overflow and for consistency.
> ---
>  hw/virtio/virtio-iommu.c | 53 ++++++++++++++++++++++++++++++++++++++++
>  hw/virtio/trace-events   |  2 ++
>  2 files changed, 55 insertions(+)
> 
> diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
> index 33115e82186..fcdf3a819f8 100644
> --- a/hw/virtio/virtio-iommu.c
> +++ b/hw/virtio/virtio-iommu.c
> @@ -125,6 +125,49 @@ static gint interval_cmp(gconstpointer a, gconstpointer b, gpointer user_data)
>      }
>  }
>  
> +static void virtio_iommu_notify_map(IOMMUMemoryRegion *mr, hwaddr virt_start,
> +                                    hwaddr virt_end, hwaddr paddr)
> +{
> +    IOMMUTLBEntry entry;
> +    IOMMUNotifierFlag flags = mr->iommu_notify_flags;
> +
> +    if (!(flags & IOMMU_NOTIFIER_MAP)) {
> +        return;
> +    }
> +
> +    trace_virtio_iommu_notify_map(mr->parent_obj.name, virt_start, virt_end,
> +                                  paddr);
> +
> +    entry.target_as = &address_space_memory;
> +    entry.addr_mask = virt_end - virt_start;
> +    entry.iova = virt_start;
> +    entry.perm = IOMMU_RW;
logically you should be able to cascade the struct virtio_iommu_req_map
*req flags field instead.
> +    entry.translated_addr = paddr;
> +
> +    memory_region_notify_iommu(mr, 0, entry);
> +}
> +
> +static void virtio_iommu_notify_unmap(IOMMUMemoryRegion *mr, hwaddr virt_start,
> +                                      hwaddr virt_end)
> +{
> +    IOMMUTLBEntry entry;
> +    IOMMUNotifierFlag flags = mr->iommu_notify_flags;
> +
> +    if (!(flags & IOMMU_NOTIFIER_UNMAP)) {
> +        return;
> +    }
> +
> +    trace_virtio_iommu_notify_unmap(mr->parent_obj.name, virt_start, virt_end);
> +
> +    entry.target_as = &address_space_memory;
> +    entry.addr_mask = virt_end - virt_start;
> +    entry.iova = virt_start;
> +    entry.perm = IOMMU_NONE;
> +    entry.translated_addr = 0;
> +
> +    memory_region_notify_iommu(mr, 0, entry);
> +}
> +
>  static void virtio_iommu_detach_endpoint_from_domain(VirtIOIOMMUEndpoint *ep)
>  {
>      if (!ep->domain) {
> @@ -315,6 +358,7 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
>      VirtIOIOMMUDomain *domain;
>      VirtIOIOMMUInterval *interval;
>      VirtIOIOMMUMapping *mapping;
> +    VirtIOIOMMUEndpoint *ep;
>  
>      if (flags & ~VIRTIO_IOMMU_MAP_F_MASK) {
>          return VIRTIO_IOMMU_S_INVAL;
> @@ -344,6 +388,10 @@ static int virtio_iommu_map(VirtIOIOMMU *s,
>  
>      g_tree_insert(domain->mappings, interval, mapping);
>  
> +    QLIST_FOREACH(ep, &domain->endpoint_list, next) {
> +        virtio_iommu_notify_map(ep->iommu_mr, virt_start, virt_end, phys_start);
> +    }
> +
>      return VIRTIO_IOMMU_S_OK;
>  }
>  
> @@ -356,6 +404,7 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
>      VirtIOIOMMUMapping *iter_val;
>      VirtIOIOMMUInterval interval, *iter_key;
>      VirtIOIOMMUDomain *domain;
> +    VirtIOIOMMUEndpoint *ep;
>      int ret = VIRTIO_IOMMU_S_OK;
>  
>      trace_virtio_iommu_unmap(domain_id, virt_start, virt_end);
> @@ -373,6 +422,10 @@ static int virtio_iommu_unmap(VirtIOIOMMU *s,
>          uint64_t current_high = iter_key->high;
>  
>          if (interval.low <= current_low && interval.high >= current_high) {
> +            QLIST_FOREACH(ep, &domain->endpoint_list, next) {
> +                virtio_iommu_notify_unmap(ep->iommu_mr, current_low,
> +                                          current_high);
> +            }
>              g_tree_remove(domain->mappings, iter_key);
>              trace_virtio_iommu_unmap_done(domain_id, current_low, current_high);
>          } else {
> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> index cf1e59de302..65a48555c78 100644
> --- a/hw/virtio/trace-events
> +++ b/hw/virtio/trace-events
> @@ -106,6 +106,8 @@ virtio_iommu_put_domain(uint32_t domain_id) "Free domain=%d"
>  virtio_iommu_translate_out(uint64_t virt_addr, uint64_t phys_addr, uint32_t sid) "0x%"PRIx64" -> 0x%"PRIx64 " for sid=%d"
>  virtio_iommu_report_fault(uint8_t reason, uint32_t flags, uint32_t endpoint, uint64_t addr) "FAULT reason=%d flags=%d endpoint=%d address =0x%"PRIx64
>  virtio_iommu_fill_resv_property(uint32_t devid, uint8_t subtype, uint64_t start, uint64_t end) "dev= %d, type=%d start=0x%"PRIx64" end=0x%"PRIx64
> +virtio_iommu_notify_map(const char *name, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64" phys_start=0x%"PRIx64
> +virtio_iommu_notify_unmap(const char *name, uint64_t virt_start, uint64_t virt_end) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
>  
>  # virtio-mem.c
>  virtio_mem_send_response(uint16_t type) "type=%" PRIu16
> 
Besides it looks good to me.

Thanks

Eric

On Fri, Oct 16, 2020 at 09:58:28AM +0200, Auger Eric wrote:
> > +static void virtio_iommu_notify_map(IOMMUMemoryRegion *mr, hwaddr virt_start,
> > +                                    hwaddr virt_end, hwaddr paddr)
> > +{
> > +    IOMMUTLBEntry entry;
> > +    IOMMUNotifierFlag flags = mr->iommu_notify_flags;
> > +
> > +    if (!(flags & IOMMU_NOTIFIER_MAP)) {
> > +        return;
> > +    }
> > +
> > +    trace_virtio_iommu_notify_map(mr->parent_obj.name, virt_start, virt_end,
> > +                                  paddr);
> > +
> > +    entry.target_as = &address_space_memory;
> > +    entry.addr_mask = virt_end - virt_start;
> > +    entry.iova = virt_start;
> > +    entry.perm = IOMMU_RW;
> logically you should be able to cascade the struct virtio_iommu_req_map
> *req flags field instead.

Agreed.

I'm also thinking of adding a check for VIRTIO_IOMMU_MAP_F_MMIO, to avoid
going further into the notifier and maybe do the same for unmap.

Thanks,
Jean