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-rw-r--r--hw/acpi/Makefile.objs1
-rw-r--r--hw/acpi/vmgenid.c242
2 files changed, 243 insertions, 0 deletions
diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index 6acf798..11c35bc 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -5,6 +5,7 @@ common-obj-$(CONFIG_ACPI_CPU_HOTPLUG) += cpu_hotplug.o
common-obj-$(CONFIG_ACPI_MEMORY_HOTPLUG) += memory_hotplug.o
common-obj-$(CONFIG_ACPI_CPU_HOTPLUG) += cpu.o
common-obj-$(CONFIG_ACPI_NVDIMM) += nvdimm.o
+common-obj-$(CONFIG_ACPI_VMGENID) += vmgenid.o
common-obj-$(call lnot,$(CONFIG_ACPI_X86)) += acpi-stub.o
common-obj-y += acpi_interface.o
diff --git a/hw/acpi/vmgenid.c b/hw/acpi/vmgenid.c
new file mode 100644
index 0000000..c8465df
--- /dev/null
+++ b/hw/acpi/vmgenid.c
@@ -0,0 +1,242 @@
+/*
+ * Virtual Machine Generation ID Device
+ *
+ * Copyright (C) 2017 Skyport Systems.
+ *
+ * Author: Ben Warren <ben@skyportsystems.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qmp-commands.h"
+#include "hw/acpi/acpi.h"
+#include "hw/acpi/aml-build.h"
+#include "hw/acpi/vmgenid.h"
+#include "hw/nvram/fw_cfg.h"
+#include "sysemu/sysemu.h"
+
+void vmgenid_build_acpi(VmGenIdState *vms, GArray *table_data, GArray *guid,
+ BIOSLinker *linker)
+{
+ Aml *ssdt, *dev, *scope, *method, *addr, *if_ctx;
+ uint32_t vgia_offset;
+ QemuUUID guid_le;
+
+ /* Fill in the GUID values. These need to be converted to little-endian
+ * first, since that's what the guest expects
+ */
+ g_array_set_size(guid, VMGENID_FW_CFG_SIZE - ARRAY_SIZE(guid_le.data));
+ guid_le = vms->guid;
+ qemu_uuid_bswap(&guid_le);
+ /* The GUID is written at a fixed offset into the fw_cfg file
+ * in order to implement the "OVMF SDT Header probe suppressor"
+ * see docs/specs/vmgenid.txt for more details
+ */
+ g_array_insert_vals(guid, VMGENID_GUID_OFFSET, guid_le.data,
+ ARRAY_SIZE(guid_le.data));
+
+ /* Put this in a separate SSDT table */
+ ssdt = init_aml_allocator();
+
+ /* Reserve space for header */
+ acpi_data_push(ssdt->buf, sizeof(AcpiTableHeader));
+
+ /* Storage for the GUID address */
+ vgia_offset = table_data->len +
+ build_append_named_dword(ssdt->buf, "VGIA");
+ scope = aml_scope("\\_SB");
+ dev = aml_device("VGEN");
+ aml_append(dev, aml_name_decl("_HID", aml_string("QEMUVGID")));
+ aml_append(dev, aml_name_decl("_CID", aml_string("VM_Gen_Counter")));
+ aml_append(dev, aml_name_decl("_DDN", aml_string("VM_Gen_Counter")));
+
+ /* Simple status method to check that address is linked and non-zero */
+ method = aml_method("_STA", 0, AML_NOTSERIALIZED);
+ addr = aml_local(0);
+ aml_append(method, aml_store(aml_int(0xf), addr));
+ if_ctx = aml_if(aml_equal(aml_name("VGIA"), aml_int(0)));
+ aml_append(if_ctx, aml_store(aml_int(0), addr));
+ aml_append(method, if_ctx);
+ aml_append(method, aml_return(addr));
+ aml_append(dev, method);
+
+ /* the ADDR method returns two 32-bit words representing the lower and
+ * upper halves * of the physical address of the fw_cfg blob
+ * (holding the GUID)
+ */
+ method = aml_method("ADDR", 0, AML_NOTSERIALIZED);
+
+ addr = aml_local(0);
+ aml_append(method, aml_store(aml_package(2), addr));
+
+ aml_append(method, aml_store(aml_add(aml_name("VGIA"),
+ aml_int(VMGENID_GUID_OFFSET), NULL),
+ aml_index(addr, aml_int(0))));
+ aml_append(method, aml_store(aml_int(0), aml_index(addr, aml_int(1))));
+ aml_append(method, aml_return(addr));
+
+ aml_append(dev, method);
+ aml_append(scope, dev);
+ aml_append(ssdt, scope);
+
+ /* attach an ACPI notify */
+ method = aml_method("\\_GPE._E05", 0, AML_NOTSERIALIZED);
+ aml_append(method, aml_notify(aml_name("\\_SB.VGEN"), aml_int(0x80)));
+ aml_append(ssdt, method);
+
+ g_array_append_vals(table_data, ssdt->buf->data, ssdt->buf->len);
+
+ /* Allocate guest memory for the Data fw_cfg blob */
+ bios_linker_loader_alloc(linker, VMGENID_GUID_FW_CFG_FILE, guid, 4096,
+ false /* page boundary, high memory */);
+
+ /* Patch address of GUID fw_cfg blob into the ADDR fw_cfg blob
+ * so QEMU can write the GUID there. The address is expected to be
+ * < 4GB, but write 64 bits anyway.
+ * The address that is patched in is offset in order to implement
+ * the "OVMF SDT Header probe suppressor"
+ * see docs/specs/vmgenid.txt for more details.
+ */
+ bios_linker_loader_write_pointer(linker,
+ VMGENID_ADDR_FW_CFG_FILE, 0, sizeof(uint64_t),
+ VMGENID_GUID_FW_CFG_FILE, VMGENID_GUID_OFFSET);
+
+ /* Patch address of GUID fw_cfg blob into the AML so OSPM can retrieve
+ * and read it. Note that while we provide storage for 64 bits, only
+ * the least-signficant 32 get patched into AML.
+ */
+ bios_linker_loader_add_pointer(linker,
+ ACPI_BUILD_TABLE_FILE, vgia_offset, sizeof(uint32_t),
+ VMGENID_GUID_FW_CFG_FILE, 0);
+
+ build_header(linker, table_data,
+ (void *)(table_data->data + table_data->len - ssdt->buf->len),
+ "SSDT", ssdt->buf->len, 1, NULL, "VMGENID");
+ free_aml_allocator();
+}
+
+void vmgenid_add_fw_cfg(VmGenIdState *vms, FWCfgState *s, GArray *guid)
+{
+ /* Create a read-only fw_cfg file for GUID */
+ fw_cfg_add_file(s, VMGENID_GUID_FW_CFG_FILE, guid->data,
+ VMGENID_FW_CFG_SIZE);
+ /* Create a read-write fw_cfg file for Address */
+ fw_cfg_add_file_callback(s, VMGENID_ADDR_FW_CFG_FILE, NULL, NULL,
+ vms->vmgenid_addr_le,
+ ARRAY_SIZE(vms->vmgenid_addr_le), false);
+}
+
+static void vmgenid_update_guest(VmGenIdState *vms)
+{
+ Object *obj = object_resolve_path_type("", TYPE_ACPI_DEVICE_IF, NULL);
+ uint32_t vmgenid_addr;
+ QemuUUID guid_le;
+
+ if (obj) {
+ /* Write the GUID to guest memory */
+ memcpy(&vmgenid_addr, vms->vmgenid_addr_le, sizeof(vmgenid_addr));
+ vmgenid_addr = le32_to_cpu(vmgenid_addr);
+ /* A zero value in vmgenid_addr means that BIOS has not yet written
+ * the address
+ */
+ if (vmgenid_addr) {
+ /* QemuUUID has the first three words as big-endian, and expect
+ * that any GUIDs passed in will always be BE. The guest,
+ * however, will expect the fields to be little-endian.
+ * Perform a byte swap immediately before writing.
+ */
+ guid_le = vms->guid;
+ qemu_uuid_bswap(&guid_le);
+ /* The GUID is written at a fixed offset into the fw_cfg file
+ * in order to implement the "OVMF SDT Header probe suppressor"
+ * see docs/specs/vmgenid.txt for more details.
+ */
+ cpu_physical_memory_write(vmgenid_addr, guid_le.data,
+ sizeof(guid_le.data));
+ /* Send _GPE.E05 event */
+ acpi_send_event(DEVICE(obj), ACPI_VMGENID_CHANGE_STATUS);
+ }
+ }
+}
+
+static void vmgenid_set_guid(Object *obj, const char *value, Error **errp)
+{
+ VmGenIdState *vms = VMGENID(obj);
+
+ if (!strcmp(value, "auto")) {
+ qemu_uuid_generate(&vms->guid);
+ } else if (qemu_uuid_parse(value, &vms->guid) < 0) {
+ error_setg(errp, "'%s. %s': Failed to parse GUID string: %s",
+ object_get_typename(OBJECT(vms)), VMGENID_GUID, value);
+ return;
+ }
+
+ vmgenid_update_guest(vms);
+}
+
+/* After restoring an image, we need to update the guest memory and notify
+ * it of a potential change to VM Generation ID
+ */
+static int vmgenid_post_load(void *opaque, int version_id)
+{
+ VmGenIdState *vms = opaque;
+ vmgenid_update_guest(vms);
+ return 0;
+}
+
+static const VMStateDescription vmstate_vmgenid = {
+ .name = "vmgenid",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .post_load = vmgenid_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT8_ARRAY(vmgenid_addr_le, VmGenIdState, sizeof(uint64_t)),
+ VMSTATE_END_OF_LIST()
+ },
+};
+
+static void vmgenid_handle_reset(void *opaque)
+{
+ VmGenIdState *vms = VMGENID(opaque);
+ /* Clear the guest-allocated GUID address when the VM resets */
+ memset(vms->vmgenid_addr_le, 0, ARRAY_SIZE(vms->vmgenid_addr_le));
+}
+
+static void vmgenid_realize(DeviceState *dev, Error **errp)
+{
+ VmGenIdState *vms = VMGENID(dev);
+ qemu_register_reset(vmgenid_handle_reset, vms);
+}
+
+static void vmgenid_device_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->vmsd = &vmstate_vmgenid;
+ dc->realize = vmgenid_realize;
+ dc->hotpluggable = false;
+
+ object_class_property_add_str(klass, VMGENID_GUID, NULL,
+ vmgenid_set_guid, NULL);
+ object_class_property_set_description(klass, VMGENID_GUID,
+ "Set Global Unique Identifier "
+ "(big-endian) or auto for random value",
+ NULL);
+}
+
+static const TypeInfo vmgenid_device_info = {
+ .name = VMGENID_DEVICE,
+ .parent = TYPE_DEVICE,
+ .instance_size = sizeof(VmGenIdState),
+ .class_init = vmgenid_device_class_init,
+};
+
+static void vmgenid_register_types(void)
+{
+ type_register_static(&vmgenid_device_info);
+}
+
+type_init(vmgenid_register_types)
generated by cgit v1.1 at 2024-12-27 20:55:43 +0000