[Qemu-devel] [RFC PATCH 12/14] spapr_pci: (Mostly) remove spapr-pci-vfio-host-bridge

[David Gibson]

Now that the regular spapr-pci-host-bridge can handle EEH, the only thing
that the spapr-pci-vfio-host-bridge variant does differently is to
automatically size its DMA window based on what the host IOMMU can do.

That's not actually that useful, since the default window used by the
regular host bridge will work with the host IOMMU configuration on all
current systems anyway.

Plus, automatically changing guest visible configuration (such as the DMA
window) based on host settings is generally a bad idea.  It's not
definitively broken, since spapr-pci-vfio-host-bridge is only supposed to
support VFIO devices which can't be migrated anyway, but still.

It's possible there are scripts or tools out there which expect
spapr-pci-vfio-host-bridge, so we don't remove it entirely.  This patch
reduces it to just a stub for backwards compatibility.

Signed-off-by: David Gibson <address@hidden>
---
 hw/ppc/spapr_pci.c          |  9 -------
 hw/ppc/spapr_pci_vfio.c     | 63 +++++++++++----------------------------------
 include/hw/pci-host/spapr.h | 11 --------
 3 files changed, 15 insertions(+), 68 deletions(-)

diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
index 5614b45..77223b9 100644
--- a/hw/ppc/spapr_pci.c
+++ b/hw/ppc/spapr_pci.c
@@ -467,15 +467,6 @@ static int spapr_phb_check_vfio_group(sPAPRPHBState *phb, 
VFIOGroup **gpp)
         return RTAS_OUT_HW_ERROR;
     }
 
-    if (!object_dynamic_cast(OBJECT(phb), "spapr-pci-vfio-host-bridge")) {
-        sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(phb);
-        /* FIXME: this is an abstraction violation */
-        if (pe->group->groupid != svphb->iommugroupid) {
-            error_report("spapr-pci-vfio-host-bridge: Bad IOMMU group");
-            return RTAS_OUT_HW_ERROR;
-        }
-    }
-
     if (gpp) {
         *gpp = pe->group;
     }
diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
index a08292a..206a0fb 100644
--- a/hw/ppc/spapr_pci_vfio.c
+++ b/hw/ppc/spapr_pci_vfio.c
@@ -19,75 +19,42 @@
 
 #include "hw/ppc/spapr.h"
 #include "hw/pci-host/spapr.h"
-#include "hw/pci/msix.h"
-#include "linux/vfio.h"
-#include "hw/vfio/vfio.h"
-#include "hw/vfio/vfio-eeh.h"
+#include "qemu/error-report.h"
+
+#define TYPE_SPAPR_PCI_VFIO_HOST_BRIDGE "spapr-pci-vfio-host-bridge"
+
+#define SPAPR_PCI_VFIO_HOST_BRIDGE(obj) \
+    OBJECT_CHECK(sPAPRPHBVFIOState, (obj), TYPE_SPAPR_PCI_VFIO_HOST_BRIDGE)
+
+typedef struct sPAPRPHBVFIOState {
+    sPAPRPHBState phb;
+
+    int32_t iommugroupid;
+} sPAPRPHBVFIOState;
 
 static Property spapr_phb_vfio_properties[] = {
     DEFINE_PROP_INT32("iommu", sPAPRPHBVFIOState, iommugroupid, -1),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-static void spapr_phb_vfio_finish_realize(sPAPRPHBState *sphb, Error **errp)
+static void spapr_phb_vfio_instance_init(Object *obj)
 {
-    sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(sphb);
-    struct vfio_iommu_spapr_tce_info info = { .argsz = sizeof(info) };
-    int ret;
-    sPAPRTCETable *tcet;
-    uint32_t liobn = svphb->phb.dma_liobn;
-
-    if (svphb->iommugroupid == -1) {
-        error_setg(errp, "Wrong IOMMU group ID %d", svphb->iommugroupid);
-        return;
-    }
-
-    ret = vfio_container_ioctl(&svphb->phb.iommu_as, svphb->iommugroupid,
-                               VFIO_CHECK_EXTENSION,
-                               (void *) VFIO_SPAPR_TCE_IOMMU);
-    if (ret != 1) {
-        error_setg_errno(errp, -ret,
-                         "spapr-vfio: SPAPR extension is not supported");
-        return;
-    }
-
-    ret = vfio_container_ioctl(&svphb->phb.iommu_as, svphb->iommugroupid,
-                               VFIO_IOMMU_SPAPR_TCE_GET_INFO, &info);
-    if (ret) {
-        error_setg_errno(errp, -ret,
-                         "spapr-vfio: get info from container failed");
-        return;
-    }
-
-    tcet = spapr_tce_new_table(DEVICE(sphb), liobn, info.dma32_window_start,
-                               SPAPR_TCE_PAGE_SHIFT,
-                               info.dma32_window_size >> SPAPR_TCE_PAGE_SHIFT,
-                               true);
-    if (!tcet) {
-        error_setg(errp, "spapr-vfio: failed to create VFIO TCE table");
-        return;
-    }
-
-    /* Register default 32bit DMA window */
-    memory_region_add_subregion(&sphb->iommu_root, tcet->bus_offset,
-                                spapr_tce_get_iommu(tcet));
+    error_report("spapr-pci-vfio-host-bridge is deprecated");
 }
 
 static void spapr_phb_vfio_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
-    sPAPRPHBClass *spc = SPAPR_PCI_HOST_BRIDGE_CLASS(klass);
 
     dc->props = spapr_phb_vfio_properties;
-    spc->finish_realize = spapr_phb_vfio_finish_realize;
 }
 
 static const TypeInfo spapr_phb_vfio_info = {
     .name          = TYPE_SPAPR_PCI_VFIO_HOST_BRIDGE,
     .parent        = TYPE_SPAPR_PCI_HOST_BRIDGE,
     .instance_size = sizeof(sPAPRPHBVFIOState),
+    .instance_init = spapr_phb_vfio_instance_init,
     .class_init    = spapr_phb_vfio_class_init,
-    .class_size    = sizeof(sPAPRPHBClass),
 };
 
 static void spapr_pci_vfio_register_types(void)
diff --git a/include/hw/pci-host/spapr.h b/include/hw/pci-host/spapr.h
index 8c8d187..fd85a21 100644
--- a/include/hw/pci-host/spapr.h
+++ b/include/hw/pci-host/spapr.h
@@ -29,14 +29,10 @@
 #include "hw/vfio/vfio-eeh.h"
 
 #define TYPE_SPAPR_PCI_HOST_BRIDGE "spapr-pci-host-bridge"
-#define TYPE_SPAPR_PCI_VFIO_HOST_BRIDGE "spapr-pci-vfio-host-bridge"
 
 #define SPAPR_PCI_HOST_BRIDGE(obj) \
     OBJECT_CHECK(sPAPRPHBState, (obj), TYPE_SPAPR_PCI_HOST_BRIDGE)
 
-#define SPAPR_PCI_VFIO_HOST_BRIDGE(obj) \
-    OBJECT_CHECK(sPAPRPHBVFIOState, (obj), TYPE_SPAPR_PCI_VFIO_HOST_BRIDGE)
-
 #define SPAPR_PCI_HOST_BRIDGE_CLASS(klass) \
      OBJECT_CLASS_CHECK(sPAPRPHBClass, (klass), TYPE_SPAPR_PCI_HOST_BRIDGE)
 #define SPAPR_PCI_HOST_BRIDGE_GET_CLASS(obj) \
@@ -44,7 +40,6 @@
 
 typedef struct sPAPRPHBClass sPAPRPHBClass;
 typedef struct sPAPRPHBState sPAPRPHBState;
-typedef struct sPAPRPHBVFIOState sPAPRPHBVFIOState;
 
 struct sPAPRPHBClass {
     PCIHostBridgeClass parent_class;
@@ -99,12 +94,6 @@ struct sPAPRPHBState {
     QLIST_ENTRY(sPAPRPHBState) list;
 };
 
-struct sPAPRPHBVFIOState {
-    sPAPRPHBState phb;
-
-    int32_t iommugroupid;
-};
-
 #define SPAPR_PCI_MAX_INDEX          255
 
 #define SPAPR_PCI_BASE_BUID          0x800000020000000ULL
-- 
2.4.3