Allow instantiating a virtio-iommu device by adding an ACPI Virtual I/O
Translation table (VIOT), which describes the relation between the
virtio-iommu and the endpoints it manages.
Add a hotplug handler for virtio-iommu on x86 and set the necessary
reserved region property. On x86, the [0xfee00000, 0xfeefffff] DMA
region is reserved for MSIs. DMA transactions to this range either
trigger IRQ remapping in the IOMMU or bypasses IOMMU translation.
Although virtio-iommu does not support IRQ remapping it must be informed
of the reserved region so that it can forward DMA transactions targeting
this region.
Signed-off-by: Jean-Philippe Brucker <jean-phili...@linaro.org>
---
include/hw/i386/pc.h | 2 ++
hw/i386/acpi-build.c | 5 +++++
hw/i386/pc.c | 28 +++++++++++++++++++++++++++-
hw/i386/Kconfig | 1 +
4 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 82cf7b7e30..f3ba1ee4c0 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -45,6 +45,8 @@ typedef struct PCMachineState {
bool pit_enabled;
bool hpet_enabled;
bool default_bus_bypass_iommu;
+ bool virtio_iommu;
+ uint16_t virtio_iommu_bdf;
uint64_t max_fw_size;
/* ACPI Memory hotplug IO base address */
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 547cd4ed9d..76845026d8 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -71,6 +71,7 @@
#include "hw/acpi/ipmi.h"
#include "hw/acpi/hmat.h"
+#include "hw/acpi/viot.h"
/* These are used to size the ACPI tables for -M pc-i440fx-1.7 and
* -M pc-i440fx-2.0. Even if the actual amount of AML generated grows
@@ -2593,6 +2594,10 @@ void acpi_build(AcpiBuildTables *tables, MachineState
*machine)
build_dmar_q35(tables_blob, tables->linker, x86ms->oem_id,
x86ms->oem_table_id);
}
+ } else if (pcms->virtio_iommu) {
+ acpi_add_table(table_offsets, tables_blob);
+ build_viot(tables_blob, tables->linker, pcms->virtio_iommu_bdf,
+ x86ms->oem_id, x86ms->oem_table_id);
}
if (machine->nvdimms_state->is_enabled) {
nvdimm_build_acpi(table_offsets, tables_blob, tables->linker,
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 7e523b913c..a31e950599 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -83,6 +83,7 @@
#include "hw/i386/intel_iommu.h"
#include "hw/net/ne2000-isa.h"
#include "standard-headers/asm-x86/bootparam.h"
+#include "hw/virtio/virtio-iommu.h"
#include "hw/virtio/virtio-pmem-pci.h"
#include "hw/virtio/virtio-mem-pci.h"
#include "hw/mem/memory-device.h"
@@ -798,6 +799,11 @@ void pc_machine_done(Notifier *notifier, void *data)
"irqchip support.");
exit(EXIT_FAILURE);
}
+
+ if (pcms->virtio_iommu && x86_iommu_get_default()) {
+ error_report("QEMU does not support multiple vIOMMUs for x86 yet.");
+ exit(EXIT_FAILURE);
+ }
}
void pc_guest_info_init(PCMachineState *pcms)
@@ -1368,6 +1374,14 @@ static void pc_machine_device_pre_plug_cb(HotplugHandler
*hotplug_dev,
} else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI) ||
object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI)) {
pc_virtio_md_pci_pre_plug(hotplug_dev, dev, errp);
+ } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) {
+ /* Declare the reserved MSI region */
+ char *resv_prop_str = g_strdup_printf("0xfee00000:0xfeefffff:%d",
+ VIRTIO_IOMMU_RESV_MEM_T_MSI);
+
+ qdev_prop_set_uint32(dev, "len-reserved-regions", 1);
+ qdev_prop_set_string(dev, "reserved-regions[0]", resv_prop_str);
+ g_free(resv_prop_str);
}
}
@@ -1381,6 +1395,17 @@ static void pc_machine_device_plug_cb(HotplugHandler
*hotplug_dev,
} else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI) ||
object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI)) {
pc_virtio_md_pci_plug(hotplug_dev, dev, errp);
+ } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) {
+ PCMachineState *pcms = PC_MACHINE(hotplug_dev);
+ PCIDevice *pdev = PCI_DEVICE(dev);
+
+ if (pcms->virtio_iommu) {
+ error_setg(errp,
+ "QEMU does not support multiple vIOMMUs for x86 yet.");
+ return;
+ }
+ pcms->virtio_iommu = true;
+ pcms->virtio_iommu_bdf = pci_get_bdf(pdev);
}
}
@@ -1422,7 +1447,8 @@ static HotplugHandler
*pc_get_hotplug_handler(MachineState *machine,
if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) ||
object_dynamic_cast(OBJECT(dev), TYPE_CPU) ||
object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI) ||
- object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI)) {
+ object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MEM_PCI) ||
+ object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) {
return HOTPLUG_HANDLER(machine);
}
diff --git a/hw/i386/Kconfig b/hw/i386/Kconfig
index ddedcef0b2..13db05d557 100644
--- a/hw/i386/Kconfig
+++ b/hw/i386/Kconfig
@@ -54,6 +54,7 @@ config PC_ACPI
select ACPI_X86
select ACPI_CPU_HOTPLUG
select ACPI_MEMORY_HOTPLUG
+ select ACPI_VIOT
select SMBUS_EEPROM
select PFLASH_CFI01
depends on ACPI_SMBUS
--
2.33.0
