[Qemu-devel] [RFC PATCH v3 16/18] spapr_pci_vfio: Enable DDW

[Alexey Kardashevskiy <aik@ozlabs.ru>]

This implements DDW for VFIO. Host kernel support is required for this.

After this patch DDW will be enabled on all machines but pseries-2.1.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v2:
* remove()/reset() callbacks use spapr_pci's ones
---
 hw/ppc/spapr_pci_vfio.c | 74 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)

diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
index e53880e..94e1361 100644
--- a/hw/ppc/spapr_pci_vfio.c
+++ b/hw/ppc/spapr_pci_vfio.c
@@ -73,6 +73,77 @@ static void spapr_phb_vfio_finish_realize(sPAPRPHBState *sphb, Error **errp)
     object_unref(OBJECT(tcet));
 
     sphb->windows_num = 1;
+
+    if (sphb->ddw_enabled) {
+        sphb->ddw_enabled = !!(info.flags & VFIO_IOMMU_SPAPR_TCE_FLAG_DDW);
+    }
+}
+
+static int spapr_pci_vfio_ddw_query(sPAPRPHBState *sphb,
+                                    uint32_t *windows_available,
+                                    uint32_t *page_size_mask)
+{
+    sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(sphb);
+    struct vfio_iommu_spapr_tce_info info = { .argsz = sizeof(info) };
+    int ret;
+
+    ret = vfio_container_ioctl(&sphb->iommu_as, svphb->iommugroupid,
+                               VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
+    if (ret) {
+        return ret;
+    }
+
+    *windows_available = info.windows_available;
+    *page_size_mask = info.page_size_mask;
+
+    return ret;
+}
+
+static int spapr_pci_vfio_ddw_create(sPAPRPHBState *sphb, uint32_t page_shift,
+                                     uint32_t window_shift, uint32_t liobn,
+                                     sPAPRTCETable **ptcet)
+{
+    sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(sphb);
+    struct vfio_iommu_spapr_tce_create create = {
+        .argsz = sizeof(create),
+        .page_shift = page_shift,
+        .window_shift = window_shift,
+        .start_addr = 0
+    };
+    int ret;
+
+    ret = vfio_container_ioctl(&sphb->iommu_as, svphb->iommugroupid,
+                               VFIO_IOMMU_SPAPR_TCE_CREATE, &create);
+    if (ret) {
+        return ret;
+    }
+
+    *ptcet = spapr_tce_new_table(DEVICE(sphb), liobn,
+                                 create.start_addr, page_shift,
+                                 1ULL << (window_shift - page_shift),
+                                 true);
+    memory_region_add_subregion(&sphb->iommu_root, (*ptcet)->bus_offset,
+                                spapr_tce_get_iommu(*ptcet));
+
+    ++sphb->windows_num;
+
+    return ret;
+}
+
+static int spapr_pci_vfio_ddw_remove(sPAPRPHBState *sphb, sPAPRTCETable *tcet)
+{
+    sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(sphb);
+    struct vfio_iommu_spapr_tce_remove remove = {
+        .argsz = sizeof(remove),
+        .start_addr = tcet->bus_offset
+    };
+    int ret;
+
+    spapr_pci_ddw_remove(sphb, tcet);
+    ret = vfio_container_ioctl(&sphb->iommu_as, svphb->iommugroupid,
+                               VFIO_IOMMU_SPAPR_TCE_REMOVE, &remove);
+
+    return ret;
 }
 
 static void spapr_phb_vfio_class_init(ObjectClass *klass, void *data)
@@ -82,6 +153,9 @@ static void spapr_phb_vfio_class_init(ObjectClass *klass, void *data)
 
     dc->props = spapr_phb_vfio_properties;
     spc->finish_realize = spapr_phb_vfio_finish_realize;
+    spc->ddw_query = spapr_pci_vfio_ddw_query;
+    spc->ddw_create = spapr_pci_vfio_ddw_create;
+    spc->ddw_remove = spapr_pci_vfio_ddw_remove;
 }
 
 static const TypeInfo spapr_phb_vfio_info = {
-- 
2.0.0