migration: disallow migrate_add_blocker during migration

If a migration is already in progress and somebody attempts
to add a migration blocker, this should rightly fail.

Add an errp parameter and a retcode return value to migrate_add_blocker.

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1484566314-3987-5-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Merged with recent 'Allow invtsc migration' change
This commit is contained in:
Ashijeet Acharya 2017-01-16 17:01:53 +05:30 committed by Dr. David Alan Gilbert
parent a3a3d8c738
commit fe44dc9180
18 changed files with 222 additions and 81 deletions

View File

@ -104,6 +104,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
unsigned int len, i, shift;
int ret;
QCowHeader header;
Error *local_err = NULL;
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
@ -252,7 +253,12 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
error_setg(&s->migration_blocker, "The qcow format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
migrate_add_blocker(s->migration_blocker);
ret = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
goto fail;
}
qemu_co_mutex_init(&s->lock);
return 0;

View File

@ -361,6 +361,7 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
VdiHeader header;
size_t bmap_size;
int ret;
Error *local_err = NULL;
logout("\n");
@ -471,7 +472,12 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
error_setg(&s->migration_blocker, "The vdi format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
migrate_add_blocker(s->migration_blocker);
ret = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
goto fail_free_bmap;
}
qemu_co_mutex_init(&s->write_lock);

View File

@ -991,6 +991,17 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
}
}
/* Disable migration when VHDX images are used */
error_setg(&s->migration_blocker, "The vhdx format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
ret = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
goto fail;
}
if (flags & BDRV_O_RDWR) {
ret = vhdx_update_headers(bs, s, false, NULL);
if (ret < 0) {
@ -1000,12 +1011,6 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
/* TODO: differencing files */
/* Disable migration when VHDX images are used */
error_setg(&s->migration_blocker, "The vhdx format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
migrate_add_blocker(s->migration_blocker);
return 0;
fail:
vhdx_close(bs);

View File

@ -941,6 +941,7 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
int ret;
BDRVVmdkState *s = bs->opaque;
uint32_t magic;
Error *local_err = NULL;
buf = vmdk_read_desc(bs->file, 0, errp);
if (!buf) {
@ -976,7 +977,13 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
error_setg(&s->migration_blocker, "The vmdk format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
migrate_add_blocker(s->migration_blocker);
ret = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
goto fail;
}
g_free(buf);
return 0;

View File

@ -422,13 +422,18 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
#endif
}
qemu_co_mutex_init(&s->lock);
/* Disable migration when VHD images are used */
error_setg(&s->migration_blocker, "The vpc format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
migrate_add_blocker(s->migration_blocker);
ret = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
goto fail;
}
qemu_co_mutex_init(&s->lock);
return 0;

View File

@ -1185,21 +1185,26 @@ static int vvfat_open(BlockDriverState *bs, QDict *options, int flags,
s->sector_count = s->faked_sectors + s->sectors_per_cluster*s->cluster_count;
if (s->first_sectors_number == 0x40) {
init_mbr(s, cyls, heads, secs);
}
qemu_co_mutex_init(&s->lock);
/* Disable migration when vvfat is used rw */
if (s->qcow) {
error_setg(&s->migration_blocker,
"The vvfat (rw) format used by node '%s' "
"does not support live migration",
bdrv_get_device_or_node_name(bs));
migrate_add_blocker(s->migration_blocker);
ret = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
goto fail;
}
}
if (s->first_sectors_number == 0x40) {
init_mbr(s, cyls, heads, secs);
}
qemu_co_mutex_init(&s->lock);
ret = 0;
fail:
qemu_opts_del(opts);

View File

@ -979,6 +979,7 @@ static void coroutine_fn v9fs_attach(void *opaque)
size_t offset = 7;
V9fsQID qid;
ssize_t err;
Error *local_err = NULL;
v9fs_string_init(&uname);
v9fs_string_init(&aname);
@ -1007,26 +1008,36 @@ static void coroutine_fn v9fs_attach(void *opaque)
clunk_fid(s, fid);
goto out;
}
/*
* disable migration if we haven't done already.
* attach could get called multiple times for the same export.
*/
if (!s->migration_blocker) {
error_setg(&s->migration_blocker,
"Migration is disabled when VirtFS export path '%s' is mounted in the guest using mount_tag '%s'",
s->ctx.fs_root ? s->ctx.fs_root : "NULL", s->tag);
err = migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_free(local_err);
error_free(s->migration_blocker);
s->migration_blocker = NULL;
clunk_fid(s, fid);
goto out;
}
s->root_fid = fid;
}
err = pdu_marshal(pdu, offset, "Q", &qid);
if (err < 0) {
clunk_fid(s, fid);
goto out;
}
err += offset;
memcpy(&s->root_qid, &qid, sizeof(qid));
trace_v9fs_attach_return(pdu->tag, pdu->id,
qid.type, qid.version, qid.path);
/*
* disable migration if we haven't done already.
* attach could get called multiple times for the same export.
*/
if (!s->migration_blocker) {
s->root_fid = fid;
error_setg(&s->migration_blocker,
"Migration is disabled when VirtFS export path '%s' is mounted in the guest using mount_tag '%s'",
s->ctx.fs_root ? s->ctx.fs_root : "NULL", s->tag);
migrate_add_blocker(s->migration_blocker);
}
out:
put_fid(pdu, fidp);
out_nofid:

View File

@ -1136,6 +1136,7 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
VirtIODevice *vdev = VIRTIO_DEVICE(qdev);
VirtIOGPU *g = VIRTIO_GPU(qdev);
bool have_virgl;
Error *local_err = NULL;
int i;
if (g->conf.max_outputs > VIRTIO_GPU_MAX_SCANOUTS) {
@ -1143,14 +1144,6 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
return;
}
g->config_size = sizeof(struct virtio_gpu_config);
g->virtio_config.num_scanouts = g->conf.max_outputs;
virtio_init(VIRTIO_DEVICE(g), "virtio-gpu", VIRTIO_ID_GPU,
g->config_size);
g->req_state[0].width = 1024;
g->req_state[0].height = 768;
g->use_virgl_renderer = false;
#if !defined(CONFIG_VIRGL) || defined(HOST_WORDS_BIGENDIAN)
have_virgl = false;
@ -1161,6 +1154,24 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
g->conf.flags &= ~(1 << VIRTIO_GPU_FLAG_VIRGL_ENABLED);
}
if (virtio_gpu_virgl_enabled(g->conf)) {
error_setg(&g->migration_blocker, "virgl is not yet migratable");
migrate_add_blocker(g->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(g->migration_blocker);
return;
}
}
g->config_size = sizeof(struct virtio_gpu_config);
g->virtio_config.num_scanouts = g->conf.max_outputs;
virtio_init(VIRTIO_DEVICE(g), "virtio-gpu", VIRTIO_ID_GPU,
g->config_size);
g->req_state[0].width = 1024;
g->req_state[0].height = 768;
if (virtio_gpu_virgl_enabled(g->conf)) {
/* use larger control queue in 3d mode */
g->ctrl_vq = virtio_add_queue(vdev, 256, virtio_gpu_handle_ctrl_cb);
@ -1187,11 +1198,6 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
dpy_gfx_replace_surface(g->scanout[i].con, NULL);
}
}
if (virtio_gpu_virgl_enabled(g->conf)) {
error_setg(&g->migration_blocker, "virgl is not yet migratable");
migrate_add_blocker(g->migration_blocker);
}
}
static void virtio_gpu_device_unrealize(DeviceState *qdev, Error **errp)

View File

@ -510,6 +510,17 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
return;
}
if (!kvm_arm_gic_can_save_restore(s)) {
error_setg(&s->migration_blocker, "This operating system kernel does "
"not support vGICv2 migration");
migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
return;
}
}
gic_init_irqs_and_mmio(s, kvm_arm_gicv2_set_irq, NULL);
for (i = 0; i < s->num_irq - GIC_INTERNAL; i++) {
@ -558,12 +569,6 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
KVM_VGIC_V2_ADDR_TYPE_CPU,
s->dev_fd);
if (!kvm_arm_gic_can_save_restore(s)) {
error_setg(&s->migration_blocker, "This operating system kernel does "
"not support vGICv2 migration");
migrate_add_blocker(s->migration_blocker);
}
if (kvm_has_gsi_routing()) {
/* set up irq routing */
kvm_init_irq_routing(kvm_state);

View File

@ -56,6 +56,19 @@ static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid)
static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
{
GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
Error *local_err = NULL;
/*
* Block migration of a KVM GICv3 ITS device: the API for saving and
* restoring the state in the kernel is not yet available
*/
error_setg(&s->migration_blocker, "vITS migration is not implemented");
migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
return;
}
s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_ITS, false);
if (s->dev_fd < 0) {
@ -73,13 +86,6 @@ static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
gicv3_its_init_mmio(s, NULL);
/*
* Block migration of a KVM GICv3 ITS device: the API for saving and
* restoring the state in the kernel is not yet available
*/
error_setg(&s->migration_blocker, "vITS migration is not implemented");
migrate_add_blocker(s->migration_blocker);
kvm_msi_use_devid = true;
kvm_gsi_direct_mapping = false;
kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();

View File

@ -103,6 +103,18 @@ static void kvm_arm_gicv3_realize(DeviceState *dev, Error **errp)
gicv3_init_irqs_and_mmio(s, kvm_arm_gicv3_set_irq, NULL);
/* Block migration of a KVM GICv3 device: the API for saving and restoring
* the state in the kernel is not yet finalised in the kernel or
* implemented in QEMU.
*/
error_setg(&s->migration_blocker, "vGICv3 migration is not implemented");
migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
return;
}
/* Try to create the device via the device control API */
s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_V3, false);
if (s->dev_fd < 0) {
@ -122,13 +134,6 @@ static void kvm_arm_gicv3_realize(DeviceState *dev, Error **errp)
kvm_arm_register_device(&s->iomem_redist, -1, KVM_DEV_ARM_VGIC_GRP_ADDR,
KVM_VGIC_V3_ADDR_TYPE_REDIST, s->dev_fd);
/* Block migration of a KVM GICv3 device: the API for saving and restoring
* the state in the kernel is not yet finalised in the kernel or
* implemented in QEMU.
*/
error_setg(&s->migration_blocker, "vGICv3 migration is not implemented");
migrate_add_blocker(s->migration_blocker);
if (kvm_has_gsi_routing()) {
/* set up irq routing */
kvm_init_irq_routing(kvm_state);

View File

@ -840,6 +840,7 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
uint8_t *pci_conf;
uint8_t attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
PCI_BASE_ADDRESS_MEM_PREFETCH;
Error *local_err = NULL;
/* IRQFD requires MSI */
if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
@ -903,9 +904,6 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
}
}
vmstate_register_ram(s->ivshmem_bar2, DEVICE(s));
pci_register_bar(PCI_DEVICE(s), 2, attr, s->ivshmem_bar2);
if (s->master == ON_OFF_AUTO_AUTO) {
s->master = s->vm_id == 0 ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
}
@ -913,8 +911,16 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
if (!ivshmem_is_master(s)) {
error_setg(&s->migration_blocker,
"Migration is disabled when using feature 'peer mode' in device 'ivshmem'");
migrate_add_blocker(s->migration_blocker);
migrate_add_blocker(s->migration_blocker, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_free(s->migration_blocker);
return;
}
}
vmstate_register_ram(s->ivshmem_bar2, DEVICE(s));
pci_register_bar(PCI_DEVICE(s), 2, attr, s->ivshmem_bar2);
}
static void ivshmem_exit(PCIDevice *dev)

View File

@ -238,8 +238,16 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
vhost_dummy_handle_output);
if (err != NULL) {
error_propagate(errp, err);
close(vhostfd);
return;
goto close_fd;
}
error_setg(&s->migration_blocker,
"vhost-scsi does not support migration");
migrate_add_blocker(s->migration_blocker, &err);
if (err) {
error_propagate(errp, err);
error_free(s->migration_blocker);
goto close_fd;
}
s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
@ -252,7 +260,7 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
if (ret < 0) {
error_setg(errp, "vhost-scsi: vhost initialization failed: %s",
strerror(-ret));
return;
goto free_vqs;
}
/* At present, channel and lun both are 0 for bootable vhost-scsi disk */
@ -261,9 +269,14 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
/* Note: we can also get the minimum tpgt from kernel */
s->target = vs->conf.boot_tpgt;
error_setg(&s->migration_blocker,
"vhost-scsi does not support migration");
migrate_add_blocker(s->migration_blocker);
return;
free_vqs:
migrate_del_blocker(s->migration_blocker);
g_free(s->dev.vqs);
close_fd:
close(vhostfd);
return;
}
static void vhost_scsi_unrealize(DeviceState *dev, Error **errp)

View File

@ -1176,6 +1176,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
{
uint64_t features;
int i, r, n_initialized_vqs = 0;
Error *local_err = NULL;
hdev->vdev = NULL;
hdev->migration_blocker = NULL;
@ -1256,7 +1257,12 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
}
if (hdev->migration_blocker != NULL) {
migrate_add_blocker(hdev->migration_blocker);
r = migrate_add_blocker(hdev->migration_blocker, &local_err);
if (local_err) {
error_report_err(local_err);
error_free(hdev->migration_blocker);
goto fail_busyloop;
}
}
hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions));

View File

@ -243,6 +243,7 @@ void remove_migration_state_change_notifier(Notifier *notify);
MigrationState *migrate_init(const MigrationParams *params);
bool migration_is_blocked(Error **errp);
bool migration_in_setup(MigrationState *);
bool migration_is_idle(MigrationState *s);
bool migration_has_finished(MigrationState *);
bool migration_has_failed(MigrationState *);
/* True if outgoing migration has entered postcopy phase */
@ -287,8 +288,12 @@ int ram_postcopy_incoming_init(MigrationIncomingState *mis);
* @migrate_add_blocker - prevent migration from proceeding
*
* @reason - an error to be returned whenever migration is attempted
*
* @errp - [out] The reason (if any) we cannot block migration right now.
*
* @returns - 0 on success, -EBUSY on failure, with errp set.
*/
void migrate_add_blocker(Error *reason);
int migrate_add_blocker(Error *reason, Error **errp);
/**
* @migrate_del_blocker - remove a blocking error from migration

View File

@ -1044,6 +1044,31 @@ bool migration_in_postcopy_after_devices(MigrationState *s)
return migration_in_postcopy(s) && s->postcopy_after_devices;
}
bool migration_is_idle(MigrationState *s)
{
if (!s) {
s = migrate_get_current();
}
switch (s->state) {
case MIGRATION_STATUS_NONE:
case MIGRATION_STATUS_CANCELLED:
case MIGRATION_STATUS_COMPLETED:
case MIGRATION_STATUS_FAILED:
return true;
case MIGRATION_STATUS_SETUP:
case MIGRATION_STATUS_CANCELLING:
case MIGRATION_STATUS_ACTIVE:
case MIGRATION_STATUS_POSTCOPY_ACTIVE:
case MIGRATION_STATUS_COLO:
return false;
case MIGRATION_STATUS__MAX:
g_assert_not_reached();
}
return false;
}
MigrationState *migrate_init(const MigrationParams *params)
{
MigrationState *s = migrate_get_current();
@ -1086,9 +1111,17 @@ MigrationState *migrate_init(const MigrationParams *params)
static GSList *migration_blockers;
void migrate_add_blocker(Error *reason)
int migrate_add_blocker(Error *reason, Error **errp)
{
migration_blockers = g_slist_prepend(migration_blockers, reason);
if (migration_is_idle(NULL)) {
migration_blockers = g_slist_prepend(migration_blockers, reason);
return 0;
}
error_propagate(errp, error_copy(reason));
error_prepend(errp, "disallowing migration blocker (migration in "
"progress) for: ");
return -EBUSY;
}
void migrate_del_blocker(Error *reason)

View File

@ -2,8 +2,9 @@
#include "qemu-common.h"
#include "migration/migration.h"
void migrate_add_blocker(Error *reason)
int migrate_add_blocker(Error *reason, Error **errp)
{
return 0;
}
void migrate_del_blocker(Error *reason)

View File

@ -710,6 +710,7 @@ int kvm_arch_init_vcpu(CPUState *cs)
uint32_t signature[3];
int kvm_base = KVM_CPUID_SIGNATURE;
int r;
Error *local_err = NULL;
memset(&cpuid_data, 0, sizeof(cpuid_data));
@ -970,7 +971,12 @@ int kvm_arch_init_vcpu(CPUState *cs)
error_setg(&invtsc_mig_blocker,
"State blocked by non-migratable CPU device"
" (invtsc flag)");
migrate_add_blocker(invtsc_mig_blocker);
r = migrate_add_blocker(invtsc_mig_blocker, &local_err);
if (local_err) {
error_report_err(local_err);
error_free(invtsc_mig_blocker);
goto fail;
}
/* for savevm */
vmstate_x86_cpu.unmigratable = 1;
}
@ -979,12 +985,12 @@ int kvm_arch_init_vcpu(CPUState *cs)
cpuid_data.cpuid.padding = 0;
r = kvm_vcpu_ioctl(cs, KVM_SET_CPUID2, &cpuid_data);
if (r) {
return r;
goto fail;
}
r = kvm_arch_set_tsc_khz(cs);
if (r < 0) {
return r;
goto fail;
}
/* vcpu's TSC frequency is either specified by user, or following
@ -1011,6 +1017,10 @@ int kvm_arch_init_vcpu(CPUState *cs)
}
return 0;
fail:
migrate_del_blocker(invtsc_mig_blocker);
return r;
}
void kvm_arch_reset_vcpu(X86CPU *cpu)