From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36951) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cFOvx-00018R-Ln for qemu-devel@nongnu.org; Fri, 09 Dec 2016 12:26:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cFOvv-0001LE-Db for qemu-devel@nongnu.org; Fri, 09 Dec 2016 12:26:09 -0500 From: John Snow Date: Fri, 9 Dec 2016 12:25:47 -0500 Message-Id: <20161209172547.31550-2-jsnow@redhat.com> In-Reply-To: <20161209172547.31550-1-jsnow@redhat.com> References: <20161209172547.31550-1-jsnow@redhat.com> Subject: [Qemu-devel] [PATCH v3 1/1] migration: disallow migrate_add_blocker during migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, qemu-block@nongnu.org, mst@redhat.com, jcody@redhat.com, quintela@redhat.com, armbru@redhat.com, groug@kaod.org, aneesh.kumar@linux.vnet.ibm.com, ashijeetacharya@gmail.com, pbonzini@redhat.com, amit.shah@redhat.com, marcandre.lureau@redhat.com, dgilbert@redhat.com, John Snow 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 --- block/qcow.c | 6 +++++- block/vdi.c | 6 +++++- block/vhdx.c | 24 ++++++++++++++---------- block/vmdk.c | 7 ++++++- block/vpc.c | 10 +++++++--- block/vvfat.c | 20 ++++++++++++-------- hw/9pfs/9p.c | 16 ++++++++++++---- hw/display/virtio-gpu.c | 29 ++++++++++++++++------------- hw/misc/ivshmem.c | 11 +++++++---- hw/scsi/vhost-scsi.c | 25 +++++++++++++++++++------ hw/virtio/vhost.c | 8 +++++++- include/migration/migration.h | 6 +++++- migration/migration.c | 35 +++++++++++++++++++++++++++++++++-- stubs/migr-blocker.c | 3 ++- target-i386/kvm.c | 16 +++++++++++++--- 15 files changed, 163 insertions(+), 59 deletions(-) diff --git a/block/qcow.c b/block/qcow.c index 7540f43..11526a1 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -252,7 +252,11 @@ 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, errp); + if (ret < 0) { + error_free(s->migration_blocker); + goto fail; + } qemu_co_mutex_init(&s->lock); return 0; diff --git a/block/vdi.c b/block/vdi.c index 96b78d5..2b56f52 100644 --- a/block/vdi.c +++ b/block/vdi.c @@ -471,7 +471,11 @@ 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, errp); + if (ret < 0) { + error_free(s->migration_blocker); + goto fail_free_bmap; + } qemu_co_mutex_init(&s->write_lock); diff --git a/block/vhdx.c b/block/vhdx.c index 0ba2f0a..d81941b 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -991,20 +991,24 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, } } - if (flags & BDRV_O_RDWR) { - ret = vhdx_update_headers(bs, s, false, NULL); - if (ret < 0) { - goto fail; - } - } - - /* 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); + ret = migrate_add_blocker(s->migration_blocker, errp); + if (ret < 0) { + error_free(s->migration_blocker); + goto fail; + } + + if (flags & BDRV_O_RDWR) { + ret = vhdx_update_headers(bs, s, false, NULL); + if (ret < 0) { + goto fail; + } + } + + /* TODO: differencing files */ return 0; fail: diff --git a/block/vmdk.c b/block/vmdk.c index a11c27a..4a45a83 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -976,7 +976,12 @@ 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, errp); + if (ret < 0) { + error_free(s->migration_blocker); + goto fail; + } + g_free(buf); return 0; diff --git a/block/vpc.c b/block/vpc.c index 8d5886f..299a8c8 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -422,13 +422,17 @@ 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, errp); + if (ret < 0) { + error_free(s->migration_blocker); + goto fail; + } + + qemu_co_mutex_init(&s->lock); return 0; diff --git a/block/vvfat.c b/block/vvfat.c index ded2109..3de3320 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -1185,22 +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); - } - - // assert(is_consistent(s)); - 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, errp); + if (ret < 0) { + error_free(s->migration_blocker); + goto fail; + } } + if (s->first_sectors_number == 0x40) { + init_mbr(s, cyls, heads, secs); + } + + // assert(is_consistent(s)); + qemu_co_mutex_init(&s->lock); + ret = 0; fail: qemu_opts_del(opts); diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index faebd91..e72ef43 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -1013,20 +1013,28 @@ static void coroutine_fn v9fs_attach(void *opaque) 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) { + int ret; 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); + ret = migrate_add_blocker(s->migration_blocker, NULL); + if (ret < 0) { + err = ret; + clunk_fid(s, fid); + goto out; + } } + + memcpy(&s->root_qid, &qid, sizeof(qid)); + trace_v9fs_attach_return(pdu->tag, pdu->id, + qid.type, qid.version, qid.path); out: put_fid(pdu, fidp); out_nofid: diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c index 5f32e1a..6e60b8c 100644 --- a/hw/display/virtio-gpu.c +++ b/hw/display/virtio-gpu.c @@ -1108,14 +1108,6 @@ 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; @@ -1127,6 +1119,22 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp) } if (virtio_gpu_virgl_enabled(g->conf)) { + error_setg(&g->migration_blocker, "virgl is not yet migratable"); + if (migrate_add_blocker(g->migration_blocker, errp) < 0) { + 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); g->cursor_vq = virtio_add_queue(vdev, 16, virtio_gpu_handle_cursor_cb); @@ -1152,11 +1160,6 @@ 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) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index abeaf3d..585cc5b 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -903,9 +903,6 @@ 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 +910,14 @@ 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); + if (migrate_add_blocker(s->migration_blocker, errp) < 0) { + 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) diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c index 5b26946..ff503d0 100644 --- a/hw/scsi/vhost-scsi.c +++ b/hw/scsi/vhost-scsi.c @@ -238,8 +238,14 @@ 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"); + ret = migrate_add_blocker(s->migration_blocker, errp); + if (ret < 0) { + goto free_blocker; } s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; @@ -252,7 +258,7 @@ 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 +267,16 @@ 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); + free_blocker: + error_free(s->migration_blocker); + close_fd: + close(vhostfd); + return; } static void vhost_scsi_unrealize(DeviceState *dev, Error **errp) diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index f7f7023..416fada 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -1157,7 +1157,13 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque, } if (hdev->migration_blocker != NULL) { - migrate_add_blocker(hdev->migration_blocker); + Error *local_err; + r = migrate_add_blocker(hdev->migration_blocker, &local_err); + if (r < 0) { + error_report_err(local_err); + error_free(hdev->migration_blocker); + goto fail_busyloop; + } } hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); diff --git a/include/migration/migration.h b/include/migration/migration.h index c309d23..8a91215 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -240,6 +240,7 @@ 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 */ @@ -284,8 +285,11 @@ 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 diff --git a/migration/migration.c b/migration/migration.c index f498ab8..713e012 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -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 +1111,15 @@ 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_setg(errp, "Cannot block a migration already in-progress"); + return -EBUSY; } void migrate_del_blocker(Error *reason) diff --git a/stubs/migr-blocker.c b/stubs/migr-blocker.c index 8ab3604..a5ba18f 100644 --- a/stubs/migr-blocker.c +++ b/stubs/migr-blocker.c @@ -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) diff --git a/target-i386/kvm.c b/target-i386/kvm.c index f62264a..8abb54d 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -961,7 +961,11 @@ 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, NULL); + if (r < 0) { + fprintf(stderr, "migrate_add_blocker failed\n"); + goto efail; + } /* for savevm */ vmstate_x86_cpu.unmigratable = 1; } @@ -969,12 +973,12 @@ 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 @@ -1001,6 +1005,12 @@ int kvm_arch_init_vcpu(CPUState *cs) } return 0; + + fail: + migrate_del_blocker(invtsc_mig_blocker); + efail: + error_free(invtsc_mig_blocker); + return r; } void kvm_arch_reset_vcpu(X86CPU *cpu) -- 2.9.3