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 | 24 ++++++++++++++++++++++-- hw/i386/Kconfig | 1 + 4 files changed, 30 insertions(+), 2 deletions(-) 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 d1c28440f4..4e46585709 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(machine, 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 789ccb6ef4..31710bc4fb 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" @@ -1367,8 +1368,11 @@ static void pc_virtio_md_pci_unplug(HotplugHandler *hotplug_dev, static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, Error **errp) { - if (object_dynamic_cast(OBJECT(dev), TYPE_X86_IOMMU_DEVICE) && - x86_iommu_get_default()) { + PCMachineState *pcms = PC_MACHINE(hotplug_dev); + + if ((object_dynamic_cast(OBJECT(dev), TYPE_X86_IOMMU_DEVICE) || + object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_IOMMU_PCI)) && + (x86_iommu_get_default() || pcms->virtio_iommu)) { error_setg(errp, "QEMU does not support multiple vIOMMUs " "for x86 yet."); return; @@ -1381,6 +1385,15 @@ 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 APIC range as the reserved MSI region */ + char *resv_prop_str = g_strdup_printf("0xfee00000:0xfeefffff:%d", + VIRTIO_IOMMU_RESV_MEM_T_MSI); + + object_property_set_uint(OBJECT(dev), "len-reserved-regions", 1, errp); + object_property_set_str(OBJECT(dev), "reserved-regions[0]", + resv_prop_str, errp); + g_free(resv_prop_str); } } @@ -1394,6 +1407,12 @@ 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); + + pcms->virtio_iommu = true; + pcms->virtio_iommu_bdf = pci_get_bdf(pdev); } } @@ -1436,6 +1455,7 @@ static HotplugHandler *pc_get_hotplug_handler(MachineState *machine, 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_IOMMU_PCI) || object_dynamic_cast(OBJECT(dev), TYPE_X86_IOMMU_DEVICE)) { 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