Re: [libvirt] [PATCH v3 1/2] Add machine type pc-1.0-qemu-kvm for live migrate compatibility with qemu-kvm

2014-09-22 Thread Michael S. Tsirkin 
On Sun, Sep 21, 2014 at 03:38:58PM +0100, Alex Bligh wrote:
 Add a machine type pc-1.0-qemu-kvm for live migrate compatibility
 with qemu-kvm version 1.0.
 
 Signed-off-by: Alex Bligh a...@alex.org.uk
 ---
  hw/acpi/piix4.c |   47 
 +--
  hw/i386/pc_piix.c   |   30 ++
  hw/timer/i8254_common.c |   10 +-
  3 files changed, 84 insertions(+), 3 deletions(-)
 
 diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
 index b72b34e..e016005 100644
 --- a/hw/acpi/piix4.c
 +++ b/hw/acpi/piix4.c
 @@ -37,6 +37,8 @@
  #include hw/acpi/memory_hotplug.h
  #include hw/acpi/acpi_dev_interface.h
  
 +extern int qemu_kvm_1_0_compat;
 +
  //#define DEBUG
  
  #ifdef DEBUG

Please dont' put extern declarations in C files.
You lose a useful type-safety compile-time check.

 @@ -200,12 +202,24 @@ static const VMStateDescription vmstate_pci_status = {
  }
  };
  
 +static const VMStateDescription vmstate_acpi_compat;
 +

Don't declare things like this, re-order them in a separate patch so forward
declarations are not necessary.

  static int acpi_load_old(QEMUFile *f, void *opaque, int version_id)
  {
  PIIX4PMState *s = opaque;
  int ret, i;
  uint16_t temp;
  
 +/* If we are expecting the inbound migration to come from
 + * qemu-kvm 1.0, it will have a version_id of 2 but really
 + * be version 3, so call back the original vmstate_load_state
 + * with a different more tolerant vmstate descriptor
 + */
 +if ((version_id == 2)  (qemu_kvm_1_0_compat)) {
 +return vmstate_load_state(f, vmstate_acpi_compat,
 +  opaque, version_id);
 +}
 +
  ret = pci_device_load(PCI_DEVICE(s), f);
  if (ret  0) {
  return ret;
 @@ -267,8 +281,9 @@ static const VMStateDescription vmstate_memhp_state = {
  };
  
  /* qemu-kvm 1.2 uses version 3 but advertised as 2
 - * To support incoming qemu-kvm 1.2 migration, change version_id
 - * and minimum_version_id to 2 below (which breaks migration from
 + * To support incoming qemu-kvm 1.2 migration, we support
 + * via a command line option a change to minimum_version_id
 + * of 2 in a _compat structure (which breaks migration from
   * qemu 1.2).
   *
   */
 @@ -307,6 +322,34 @@ static const VMStateDescription vmstate_acpi = {
  }
  };
  
 +static const VMStateDescription vmstate_acpi_compat = {
 +.name = piix4_pm,
 +.version_id = 3,
 +.minimum_version_id = 2,
 +.minimum_version_id_old = 1,
 +.load_state_old = NULL, /* to avoid recursion */
 +.post_load = vmstate_acpi_post_load,
 +.fields  = (VMStateField[]) {
 +VMSTATE_PCI_DEVICE(parent_obj, PIIX4PMState),
 +VMSTATE_UINT16(ar.pm1.evt.sts, PIIX4PMState),
 +VMSTATE_UINT16(ar.pm1.evt.en, PIIX4PMState),
 +VMSTATE_UINT16(ar.pm1.cnt.cnt, PIIX4PMState),
 +VMSTATE_STRUCT(apm, PIIX4PMState, 0, vmstate_apm, APMState),
 +VMSTATE_TIMER(ar.tmr.timer, PIIX4PMState),
 +VMSTATE_INT64(ar.tmr.overflow_time, PIIX4PMState),
 +VMSTATE_STRUCT(ar.gpe, PIIX4PMState, 2, vmstate_gpe, ACPIGPE),
 +VMSTATE_STRUCT_TEST(
 +acpi_pci_hotplug.acpi_pcihp_pci_status[ACPI_PCIHP_BSEL_DEFAULT],
 +PIIX4PMState,
 +vmstate_test_no_use_acpi_pci_hotplug,
 +2, vmstate_pci_status,
 +struct AcpiPciHpPciStatus),
 +VMSTATE_PCI_HOTPLUG(acpi_pci_hotplug, PIIX4PMState,
 +vmstate_test_use_acpi_pci_hotplug),
 +VMSTATE_END_OF_LIST()
 +}
 +};
 +
  static void piix4_reset(void *opaque)
  {
  PIIX4PMState *s = opaque;
 diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
 index 7081c08..48a4942 100644
 --- a/hw/i386/pc_piix.c
 +++ b/hw/i386/pc_piix.c
 @@ -70,6 +70,8 @@ static bool smbios_legacy_mode;
  static bool gigabyte_align = true;
  static bool has_reserved_memory = true;
  
 +int qemu_kvm_1_0_compat;
 +
  /* PC hardware initialisation */
  static void pc_init1(MachineState *machine,
   int pci_enabled,
 @@ -386,6 +388,14 @@ static void pc_init_pci_1_2(MachineState *machine)
  pc_init_pci(machine);
  }
  
 +/* PC machine init function for qemu-kvm 1.0 */
 +static void pc_init_pci_1_2_qemu_kvm(MachineState *machine)
 +{
 +qemu_kvm_1_0_compat = 1;
 +pc_compat_1_2(machine);
 +pc_init_pci(machine);
 +}
 +
  /* PC init function for pc-0.10 to pc-0.13 */
  static void pc_init_pci_no_kvmclock(MachineState *machine)
  {
 @@ -644,6 +654,25 @@ static QEMUMachine pc_machine_v1_0 = {
  .hw_version = 1.0,
  };
  
 +#define PC_COMPAT_1_0_QEMU_KVM \
 +PC_COMPAT_1_0,\
 +{\
 +.driver   = cirrus-vga,\
 +.property = vgamem_mb,\
 +.value= stringify(16),\
 +}
 +
 +static QEMUMachine pc_machine_v1_0_qemu_kvm = {
 +PC_I440FX_1_2_MACHINE_OPTIONS,
 +.name = pc-1.0-qemu-kvm,

I think pc-qemu-kvm-1.0 is slightly better - more

[libvirt] [PATCH v3 1/2] Add machine type pc-1.0-qemu-kvm for live migrate compatibility with qemu-kvm

2014-09-21 Thread Alex Bligh 
Add a machine type pc-1.0-qemu-kvm for live migrate compatibility
with qemu-kvm version 1.0.

Signed-off-by: Alex Bligh a...@alex.org.uk
---
 hw/acpi/piix4.c |   47 +--
 hw/i386/pc_piix.c   |   30 ++
 hw/timer/i8254_common.c |   10 +-
 3 files changed, 84 insertions(+), 3 deletions(-)

diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index b72b34e..e016005 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -37,6 +37,8 @@
 #include hw/acpi/memory_hotplug.h
 #include hw/acpi/acpi_dev_interface.h
 
+extern int qemu_kvm_1_0_compat;
+
 //#define DEBUG
 
 #ifdef DEBUG
@@ -200,12 +202,24 @@ static const VMStateDescription vmstate_pci_status = {
 }
 };
 
+static const VMStateDescription vmstate_acpi_compat;
+
 static int acpi_load_old(QEMUFile *f, void *opaque, int version_id)
 {
 PIIX4PMState *s = opaque;
 int ret, i;
 uint16_t temp;
 
+/* If we are expecting the inbound migration to come from
+ * qemu-kvm 1.0, it will have a version_id of 2 but really
+ * be version 3, so call back the original vmstate_load_state
+ * with a different more tolerant vmstate descriptor
+ */
+if ((version_id == 2)  (qemu_kvm_1_0_compat)) {
+return vmstate_load_state(f, vmstate_acpi_compat,
+  opaque, version_id);
+}
+
 ret = pci_device_load(PCI_DEVICE(s), f);
 if (ret  0) {
 return ret;
@@ -267,8 +281,9 @@ static const VMStateDescription vmstate_memhp_state = {
 };
 
 /* qemu-kvm 1.2 uses version 3 but advertised as 2
- * To support incoming qemu-kvm 1.2 migration, change version_id
- * and minimum_version_id to 2 below (which breaks migration from
+ * To support incoming qemu-kvm 1.2 migration, we support
+ * via a command line option a change to minimum_version_id
+ * of 2 in a _compat structure (which breaks migration from
  * qemu 1.2).
  *
  */
@@ -307,6 +322,34 @@ static const VMStateDescription vmstate_acpi = {
 }
 };
 
+static const VMStateDescription vmstate_acpi_compat = {
+.name = piix4_pm,
+.version_id = 3,
+.minimum_version_id = 2,
+.minimum_version_id_old = 1,
+.load_state_old = NULL, /* to avoid recursion */
+.post_load = vmstate_acpi_post_load,
+.fields  = (VMStateField[]) {
+VMSTATE_PCI_DEVICE(parent_obj, PIIX4PMState),
+VMSTATE_UINT16(ar.pm1.evt.sts, PIIX4PMState),
+VMSTATE_UINT16(ar.pm1.evt.en, PIIX4PMState),
+VMSTATE_UINT16(ar.pm1.cnt.cnt, PIIX4PMState),
+VMSTATE_STRUCT(apm, PIIX4PMState, 0, vmstate_apm, APMState),
+VMSTATE_TIMER(ar.tmr.timer, PIIX4PMState),
+VMSTATE_INT64(ar.tmr.overflow_time, PIIX4PMState),
+VMSTATE_STRUCT(ar.gpe, PIIX4PMState, 2, vmstate_gpe, ACPIGPE),
+VMSTATE_STRUCT_TEST(
+acpi_pci_hotplug.acpi_pcihp_pci_status[ACPI_PCIHP_BSEL_DEFAULT],
+PIIX4PMState,
+vmstate_test_no_use_acpi_pci_hotplug,
+2, vmstate_pci_status,
+struct AcpiPciHpPciStatus),
+VMSTATE_PCI_HOTPLUG(acpi_pci_hotplug, PIIX4PMState,
+vmstate_test_use_acpi_pci_hotplug),
+VMSTATE_END_OF_LIST()
+}
+};
+
 static void piix4_reset(void *opaque)
 {
 PIIX4PMState *s = opaque;
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 7081c08..48a4942 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -70,6 +70,8 @@ static bool smbios_legacy_mode;
 static bool gigabyte_align = true;
 static bool has_reserved_memory = true;
 
+int qemu_kvm_1_0_compat;
+
 /* PC hardware initialisation */
 static void pc_init1(MachineState *machine,
  int pci_enabled,
@@ -386,6 +388,14 @@ static void pc_init_pci_1_2(MachineState *machine)
 pc_init_pci(machine);
 }
 
+/* PC machine init function for qemu-kvm 1.0 */
+static void pc_init_pci_1_2_qemu_kvm(MachineState *machine)
+{
+qemu_kvm_1_0_compat = 1;
+pc_compat_1_2(machine);
+pc_init_pci(machine);
+}
+
 /* PC init function for pc-0.10 to pc-0.13 */
 static void pc_init_pci_no_kvmclock(MachineState *machine)
 {
@@ -644,6 +654,25 @@ static QEMUMachine pc_machine_v1_0 = {
 .hw_version = 1.0,
 };
 
+#define PC_COMPAT_1_0_QEMU_KVM \
+PC_COMPAT_1_0,\
+{\
+.driver   = cirrus-vga,\
+.property = vgamem_mb,\
+.value= stringify(16),\
+}
+
+static QEMUMachine pc_machine_v1_0_qemu_kvm = {
+PC_I440FX_1_2_MACHINE_OPTIONS,
+.name = pc-1.0-qemu-kvm,
+.init = pc_init_pci_1_2_qemu_kvm,
+.compat_props = (GlobalProperty[]) {
+PC_COMPAT_1_0_QEMU_KVM,
+{ /* end of list */ }
+},
+.hw_version = 1.0,
+};
+
 #define PC_COMPAT_0_15 \
 PC_COMPAT_1_0
 
@@ -886,6 +915,7 @@ static void pc_machine_init(void)
 qemu_register_pc_machine(pc_machine_v1_2);
 qemu_register_pc_machine(pc_machine_v1_1);
 qemu_register_pc_machine(pc_machine_v1_0);
+