[Qemu-devel] [PATCH 2/2] i386: Add a Virtual Machine Generation ID device.

[Gal Hammer <ghammer@redhat.com>]

Based on Microsoft's sepecifications (paper can be dowloaded from
http://go.microsoft.com/fwlink/?LinkId=260709), add a device
description to the SSDT ACPI table.

The GUID is set using a new "-vmgenid" command line parameter.

Signed-off-by: Gal Hammer <ghammer@redhat.com>
---
 hw/i386/acpi-build.c  | 23 +++++++++++++++++++++++
 hw/i386/ssdt-misc.dsl | 33 +++++++++++++++++++++++++++++++++
 qemu-options.hx       |  9 +++++++++
 vl.c                  | 11 +++++++++++
 4 files changed, 76 insertions(+)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 816c6d9..838c72c 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -54,6 +54,9 @@
 #include "qapi/qmp/qint.h"
 #include "qom/qom-qobject.h"
 
+extern uint8_t vm_generation_id[16];
+extern bool vm_generation_id_set;
+
 /* 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
  * a little bit, there should be plenty of free space since the DSDT
@@ -1051,6 +1054,7 @@ build_ssdt(GArray *table_data, GArray *linker,
     unsigned acpi_cpus = guest_info->apic_id_limit;
     int ssdt_start = table_data->len;
     uint8_t *ssdt_ptr;
+    uint32_t vm_gid_physical_address;
     int i;
 
     /* The current AML generator can cover the APIC ID range [0..255],
@@ -1076,6 +1080,25 @@ build_ssdt(GArray *table_data, GArray *linker,
     ACPI_BUILD_SET_LE(ssdt_ptr, sizeof(ssdp_misc_aml),
                       ssdt_isa_pest[0], 16, misc->pvpanic_port);
 
+    if (vm_generation_id_set) {
+        uint8_t *vm_gid_ptr;
+
+        vm_gid_physical_address = ssdt_start +  ssdt_acpi_vm_gid[0];
+        vm_gid_ptr = acpi_data_get_ptr(ssdt_ptr, sizeof(ssdp_misc_aml),
+                                       ssdt_acpi_vm_gid[0], 16);
+        memcpy(vm_gid_ptr, vm_generation_id, sizeof(vm_generation_id));
+
+        bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
+                                       ACPI_BUILD_TABLE_FILE,
+                                       table_data, ssdt_ptr + ssdt_acpi_vm_gid_addr[0],
+                                       sizeof(uint32_t));
+    } else {
+        vm_gid_physical_address = 0;
+    }
+
+    ACPI_BUILD_SET_LE(ssdt_ptr, sizeof(ssdp_misc_aml),
+                      ssdt_acpi_vm_gid_addr[0], 32, vm_gid_physical_address);
+
     ACPI_BUILD_SET_LE(ssdt_ptr, sizeof(ssdp_misc_aml),
                       ssdt_mctrl_nr_slots[0], 32, nr_mem);
 
diff --git a/hw/i386/ssdt-misc.dsl b/hw/i386/ssdt-misc.dsl
index d329b8b..8a001a7 100644
--- a/hw/i386/ssdt-misc.dsl
+++ b/hw/i386/ssdt-misc.dsl
@@ -118,6 +118,39 @@ DefinitionBlock ("ssdt-misc.aml", "SSDT", 0x01, "BXPC", "BXSSDTSUSP", 0x1)
         }
     }
 
+    Scope(\_SB) {
+
+        Device(VMGI) {
+            Name(_HID, "QEMU0002")
+            Name(_CID, "VM_Gen_Counter")
+            Name(_DDN, "VM_Gen_Counter")
+
+            ACPI_EXTRACT_NAME_DWORD_CONST ssdt_acpi_vm_gid_addr
+            Name(VGIA, 0x12345678)
+
+            ACPI_EXTRACT_NAME_BUFFER16 ssdt_acpi_vm_gid
+            Name(VGID, Buffer(16) {
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 })
+
+            Method(_STA, 0, NotSerialized) {
+                Store(VGIA, Local0)
+                If (LEqual(Local0, Zero)) {
+                    Return (0x00)
+                } Else {
+                    Return (0x0F)
+                }
+            }
+
+            Method(ADDR, 0, Serialized) {
+                Store(Package(2) { }, Local0)
+                Store(VGIA, Index(Local0, 0))
+                Store(0x0000, Index(Local0, 1))
+                return (Local0)
+            }
+        }
+    }
+
     External(MEMORY_SLOT_NOTIFY_METHOD, MethodObj)
     Scope(\_SB.PCI0) {
         Device(MEMORY_HOPTLUG_DEVICE) {
diff --git a/qemu-options.hx b/qemu-options.hx
index 96516c1..a6d475c 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -369,6 +369,15 @@ STEXI
 Set system UUID.
 ETEXI
 
+DEF("vmgenid", HAS_ARG, QEMU_OPTION_vmgenid,
+    "-vmgenid %08x-%04x-%04x-%04x-%012x\n"
+    "                specify the virtual machine generation ID\n", QEMU_ARCH_I386)
+STEXI
+@item -uuid @var{uuid}
+@findex -uuid
+Set the virtual machine generation ID.
+ETEXI
+
 STEXI
 @end table
 ETEXI
diff --git a/vl.c b/vl.c
index a8029d5..a5ef0d5 100644
--- a/vl.c
+++ b/vl.c
@@ -203,6 +203,9 @@ NodeInfo numa_info[MAX_NODES];
 uint8_t qemu_uuid[16];
 bool qemu_uuid_set;
 
+uint8_t vm_generation_id[16];
+bool vm_generation_id_set;
+
 static QEMUBootSetHandler *boot_set_handler;
 static void *boot_set_opaque;
 
@@ -3784,6 +3787,14 @@ int main(int argc, char **argv, char **envp)
                 }
                 qemu_uuid_set = true;
                 break;
+	    case QEMU_OPTION_vmgenid:
+	        if(qemu_uuid_parse(optarg, vm_generation_id) < 0) {
+	            fprintf(stderr, "Fail to parse UUID string."
+	                    " Wrong format.\n");
+	            exit(1);
+	        }
+	        vm_generation_id_set = true;
+	        break;
 	    case QEMU_OPTION_option_rom:
 		if (nb_option_roms >= MAX_OPTION_ROMS) {
 		    fprintf(stderr, "Too many option ROMs\n");
-- 
1.9.3