[RFC PATCH 2/4] hw/pci: Add iommu option for pci root bus

[Wang Xingang]

From: Xingang Wang <wangxingang5@huawei.com>

This add iommu option for pci root bus, including primary bus
and pxb root bus. Default option is set to true, and the option
is valid only if the iommu option for machine is properly set.

Signed-off-by: Xingang Wang <wangxingang5@huawei.com>
Signed-off-by: Jiahui Cen <cenjiahui@huawei.com>
---
 hw/arm/virt.c                       | 29 +++++++++++++++++++++++++++++
 hw/pci-bridge/pci_expander_bridge.c |  6 ++++++
 hw/pci/pci.c                        |  2 +-
 include/hw/arm/virt.h               |  1 +
 4 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 371147f3ae..0c9e549759 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -79,6 +79,7 @@
 #include "hw/virtio/virtio-iommu.h"
 #include "hw/char/pl011.h"
 #include "qemu/guest-random.h"
+#include "include/hw/pci/pci_bus.h"
 
 #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
     static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
@@ -1232,6 +1233,10 @@ static void create_smmu(const VirtMachineState *vms,
 
     dev = qdev_new("arm-smmuv3");
 
+    if (vms->primary_bus_iommu) {
+        bus->flags |= PCI_BUS_IOMMU;
+    }
+
     object_property_set_link(OBJECT(dev), "primary-bus", OBJECT(bus),
                              &error_abort);
     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
@@ -2305,6 +2310,20 @@ static void virt_set_iommu(Object *obj, const char 
*value, Error **errp)
     }
 }
 
+static bool virt_get_primary_bus_iommu(Object *obj, Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(obj);
+
+    return vms->primary_bus_iommu;
+}
+
+static void virt_set_primary_bus_iommu(Object *obj, bool value, Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(obj);
+
+    vms->primary_bus_iommu = value;
+}
+
 static CpuInstanceProperties
 virt_cpu_index_to_props(MachineState *ms, unsigned cpu_index)
 {
@@ -2629,6 +2648,13 @@ static void virt_machine_class_init(ObjectClass *oc, 
void *data)
                                           "Set the IOMMU type. "
                                           "Valid values are none and smmuv3");
 
+    object_class_property_add_bool(oc, "primary_bus_iommu",
+                                  virt_get_primary_bus_iommu,
+                                  virt_set_primary_bus_iommu);
+    object_class_property_set_description(oc, "primary_bus_iommu",
+                                          "Set on/off to enable/disable "
+                                          "iommu for primary bus");
+
     object_class_property_add_bool(oc, "ras", virt_get_ras,
                                    virt_set_ras);
     object_class_property_set_description(oc, "ras",
@@ -2696,6 +2722,9 @@ static void virt_instance_init(Object *obj)
     /* Default disallows iommu instantiation */
     vms->iommu = VIRT_IOMMU_NONE;
 
+    /* Iommu is enabled by default for primary bus */
+    vms->primary_bus_iommu = true;
+
     /* Default disallows RAS instantiation */
     vms->ras = false;
 
diff --git a/hw/pci-bridge/pci_expander_bridge.c 
b/hw/pci-bridge/pci_expander_bridge.c
index aedded1064..7971ce9bd9 100644
--- a/hw/pci-bridge/pci_expander_bridge.c
+++ b/hw/pci-bridge/pci_expander_bridge.c
@@ -57,6 +57,7 @@ struct PXBDev {
 
     uint8_t bus_nr;
     uint16_t numa_node;
+    bool iommu;
 };
 
 static PXBDev *convert_to_pxb(PCIDevice *dev)
@@ -254,6 +255,10 @@ static void pxb_dev_realize_common(PCIDevice *dev, bool 
pcie, Error **errp)
     bus->address_space_io = pci_get_bus(dev)->address_space_io;
     bus->map_irq = pxb_map_irq_fn;
 
+    if (pxb->iommu) {
+       bus->flags |= PCI_BUS_IOMMU;
+    }
+
     PCI_HOST_BRIDGE(ds)->bus = bus;
 
     pxb_register_bus(dev, bus, &local_err);
@@ -301,6 +306,7 @@ static Property pxb_dev_properties[] = {
     /* Note: 0 is not a legal PXB bus number. */
     DEFINE_PROP_UINT8("bus_nr", PXBDev, bus_nr, 0),
     DEFINE_PROP_UINT16("numa_node", PXBDev, numa_node, NUMA_NODE_UNASSIGNED),
+    DEFINE_PROP_BOOL("iommu", PXBDev, iommu, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index a9ebef8a35..dc969989c9 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -2712,7 +2712,7 @@ AddressSpace *pci_device_iommu_address_space(PCIDevice 
*dev)
 
         iommu_bus = parent_bus;
     }
-    if (iommu_bus && iommu_bus->iommu_fn) {
+    if (pci_bus_has_iommu(bus) && iommu_bus && iommu_bus->iommu_fn) {
         return iommu_bus->iommu_fn(bus, iommu_bus->iommu_opaque, devfn);
     }
     return &address_space_memory;
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index ee9a93101e..babe829486 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -147,6 +147,7 @@ struct VirtMachineState {
     OnOffAuto acpi;
     VirtGICType gic_version;
     VirtIOMMUType iommu;
+    bool primary_bus_iommu;
     VirtMSIControllerType msi_controller;
     uint16_t virtio_iommu_bdf;
     struct arm_boot_info bootinfo;
-- 
2.19.1