Re: [libvirt] [PATCH v4] Add machine parameter qemu-kvm-migration for live migrate compatibility with qemu-kvm

Add a machine parameter qemu-kvm-migration for live migrate compatibility with qemu-kvm version 1.0. Usage: -machine pc-1.0,qemu-kvm-migration=on

This has three effects: 1. cirrus-vga.vgamem_mb defaults to 16 rather than 8 2. A type 2 piix4_pm record is interpreted as being type 3 3. A type 2 i8254 PIT common state is interpreted as being type 3 Signed-off-by: Alex Bligh <alex(a)alex.org.uk&gt;

--- hw/acpi/piix4.c | 47 +++++++++++++++++++++++++++++++++++++++++++++-- hw/core/machine.c | 16 ++++++++++++++++ hw/i386/pc.c | 1 + hw/i386/pc_piix.c | 25 +++++++++++++++++++++++++ hw/timer/i8254_common.c | 11 ++++++++++- include/hw/boards.h | 7 +++++++ vl.c | 7 +++++++ 7 files changed, 111 insertions(+), 3 deletions(-) diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c index b72b34e..3c9da23 100644 --- a/hw/acpi/piix4.c +++ b/hw/acpi/piix4.c @@ -200,12 +200,26 @@ 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_opt_get_bool(qemu_get_machine_opts(), "qemu-kvm-migration", + DEFAULT_QEMU_KVM_MIGRATION)) { + 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/core/machine.c b/hw/core/machine.c index 7a66c57..bbccba9 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -235,6 +235,20 @@ static void machine_set_firmware(Object *obj, const char *value, Error **errp) ms->firmware = g_strdup(value); } +static bool machine_get_qemu_kvm_migration(Object *obj, Error **errp) +{ + MachineState *ms = MACHINE(obj); + + return ms->qemu_kvm_migration; +} + +static void machine_set_qemu_kvm_migration(Object *obj, bool value, Error **errp) +{ + MachineState *ms = MACHINE(obj); + + ms->qemu_kvm_migration = value; +} + static void machine_initfn(Object *obj) { object_property_add_str(obj, "accel", @@ -274,6 +288,8 @@ static void machine_initfn(Object *obj) object_property_add_bool(obj, "usb", machine_get_usb, machine_set_usb, NULL); object_property_add_str(obj, "firmware", machine_get_firmware, machine_set_firmware, NULL); + object_property_add_bool(obj, "qemu-kvm-migration", + machine_get_qemu_kvm_migration, machine_set_qemu_kvm_migration, NULL); } static void machine_finalize(Object *obj) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 2cf22b1..c74f2f9 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -1516,6 +1516,7 @@ static void pc_generic_machine_class_init(ObjectClass *oc, void *data) mc->alias = qm->alias; mc->desc = qm->desc; mc->init = qm->init; + mc->earlyinit = qm->earlyinit; mc->reset = qm->reset; mc->hot_add_cpu = qm->hot_add_cpu; mc->kvm_type = qm->kvm_type; diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c index 7081c08..0f122e2 100644 --- a/hw/i386/pc_piix.c +++ b/hw/i386/pc_piix.c @@ -386,6 +386,21 @@ static void pc_init_pci_1_2(MachineState *machine) pc_init_pci(machine); } +static void pc_early_init_pci_1_0(MachineState *machine) +{ + /* default value of cirrus-vga.vgamem_mb should be 16 if migrating from qemu-kvm */ + if (qemu_opt_get_bool(qemu_get_machine_opts(), "qemu-kvm-migration", + DEFAULT_QEMU_KVM_MIGRATION)) { + GlobalProperty *gp; + MachineClass *mc = MACHINE_GET_CLASS(machine); + for (gp = mc->compat_props; gp->driver; gp++) { + if (!strcmp(gp->driver, "cirrus-vga") && !strcmp(gp->property, "vgamem_mb")) { + gp->value = stringify(16); + } + } + } +} + /* PC init function for pc-0.10 to pc-0.13 */ static void pc_init_pci_no_kvmclock(MachineState *machine) { @@ -614,6 +629,11 @@ static QEMUMachine pc_machine_v1_1 = { }, }; +/* NB cirrus-vga default value is 8MB anyway, save if we + * monkey patch it to change the default when the qemu-kvm-migration + * machine parameter is selected + */ +

#define PC_COMPAT_1_0 \ PC_COMPAT_1_1,\ {\ @@ -632,10 +652,15 @@ static QEMUMachine pc_machine_v1_1 = { .driver = TYPE_USB_DEVICE,\ .property = "full-path",\ .value = "no",\ + },{\ + .driver = "cirrus-vga",\ + .property = "vgamem_mb",\ + .value = stringify(8),\ } static QEMUMachine pc_machine_v1_0 = { PC_I440FX_1_2_MACHINE_OPTIONS, + .earlyinit = pc_early_init_pci_1_0, .name = "pc-1.0", .compat_props = (GlobalProperty[]) { PC_COMPAT_1_0, diff --git a/hw/timer/i8254_common.c b/hw/timer/i8254_common.c index 07345f6..0342e93 100644 --- a/hw/timer/i8254_common.c +++ b/hw/timer/i8254_common.c @@ -257,6 +257,14 @@ static int pit_dispatch_post_load(void *opaque, int version_id) return 0; } +static bool has_irq_disabled(void *opaque, int version_id) +{ + return (version_id >= 3) || + ((version_id == 2) && + qemu_opt_get_bool(qemu_get_machine_opts(), "qemu-kvm-migration", + DEFAULT_QEMU_KVM_MIGRATION)); +} + static const VMStateDescription vmstate_pit_common = { .name = "i8254", .version_id = 3, @@ -266,7 +274,8 @@ static const VMStateDescription vmstate_pit_common = { .pre_save = pit_dispatch_pre_save, .post_load = pit_dispatch_post_load, .fields = (VMStateField[]) { - VMSTATE_UINT32_V(channels[0].irq_disabled, PITCommonState, 3), + VMSTATE_UINT32_TEST(channels[0].irq_disabled, PITCommonState, + has_irq_disabled), VMSTATE_STRUCT_ARRAY(channels, PITCommonState, 3, 2, vmstate_pit_channel, PITChannelState), VMSTATE_INT64(channels[0].next_transition_time, diff --git a/include/hw/boards.h b/include/hw/boards.h index 605a970..ffde5dd 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -13,6 +13,8 @@ typedef struct MachineState MachineState; typedef void QEMUMachineInitFunc(MachineState *ms); +typedef void QEMUMachineEarlyInitFunc(MachineState *ms); + typedef void QEMUMachineResetFunc(void); typedef void QEMUMachineHotAddCPUFunc(const int64_t id, Error **errp); @@ -24,6 +26,7 @@ struct QEMUMachine { const char *alias; const char *desc; QEMUMachineInitFunc *init; + QEMUMachineEarlyInitFunc *earlyinit; QEMUMachineResetFunc *reset; QEMUMachineHotAddCPUFunc *hot_add_cpu; QEMUMachineGetKvmtypeFunc *kvm_type; @@ -59,6 +62,8 @@ int qemu_register_machine(QEMUMachine *m); #define MACHINE_CLASS(klass) \ OBJECT_CLASS_CHECK(MachineClass, (klass), TYPE_MACHINE) +#define DEFAULT_QEMU_KVM_MIGRATION false + MachineClass *find_default_machine(void); extern MachineState *current_machine; @@ -81,6 +86,7 @@ struct MachineClass { const char *desc; void (*init)(MachineState *state); + void (*earlyinit)(MachineState *state); void (*reset)(void); void (*hot_add_cpu)(const int64_t id, Error **errp); int (*kvm_type)(const char *arg); @@ -123,6 +129,7 @@ struct MachineState { bool mem_merge; bool usb; char *firmware; + bool qemu_kvm_migration; ram_addr_t ram_size; ram_addr_t maxram_size; diff --git a/vl.c b/vl.c index fe451aa..622afea 100644 --- a/vl.c +++ b/vl.c @@ -387,6 +387,10 @@ static QemuOptsList qemu_machine_opts = { .name = PC_MACHINE_MAX_RAM_BELOW_4G, .type = QEMU_OPT_SIZE, .help = "maximum ram below the 4G boundary (32bit boundary)", + },{ + .name = "qemu-kvm-migration", + .type = QEMU_OPT_BOOL, + .help = "enable/disable migration compatibility from qemu-kvm", }, { /* End of list */ } }, @@ -1557,6 +1561,7 @@ static void machine_class_init(ObjectClass *oc, void *data) mc->alias = qm->alias; mc->desc = qm->desc; mc->init = qm->init; + mc->earlyinit = qm->earlyinit; mc->reset = qm->reset; mc->hot_add_cpu = qm->hot_add_cpu; mc->kvm_type = qm->kvm_type; @@ -4003,6 +4008,8 @@ int main(int argc, char **argv, char **envp) OBJECT_CLASS(machine_class)))); object_property_add_child(object_get_root(), "machine", OBJECT(current_machine), &error_abort); + if (machine_class->earlyinit) + machine_class->earlyinit(current_machine); cpu_exec_init_all(); if (machine_class->hw_version) { -- 1.7.9.5