| Message ID | 20230731121018.2856310-5-fengli@smartx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Implement reconnect for vhost-user-scsi | expand |
> On Jul 31, 2023, at 8:10 AM, Li Feng <fengli@smartx.com> wrote: > > If the backend crashes and restarts, the device is broken. > This patch adds reconnect for vhost-user-scsi. > > Tested with spdk backend. > > Signed-off-by: Li Feng <fengli@smartx.com> Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com> > --- > hw/scsi/vhost-user-scsi.c | 199 +++++++++++++++++++++++++--- > include/hw/virtio/vhost-user-scsi.h | 4 + > 2 files changed, 184 insertions(+), 19 deletions(-) > > diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c > index ee99b19e7a..5bf012461b 100644 > --- a/hw/scsi/vhost-user-scsi.c > +++ b/hw/scsi/vhost-user-scsi.c > @@ -43,26 +43,54 @@ enum VhostUserProtocolFeature { > VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13, > }; > > +static int vhost_user_scsi_start(VHostUserSCSI *s) > +{ > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + int ret; > + > + ret = vhost_scsi_common_start(vsc); > + s->started_vu = (ret < 0 ? false : true); > + > + return ret; > +} > + > +static void vhost_user_scsi_stop(VHostUserSCSI *s) > +{ > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + > + if (!s->started_vu) { > + return; > + } > + s->started_vu = false; > + > + vhost_scsi_common_stop(vsc); > +} > + > static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status) > { > VHostUserSCSI *s = (VHostUserSCSI *)vdev; > + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > - bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running; > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + bool should_start = virtio_device_should_start(vdev, status); > + int ret; > > - if (vhost_dev_is_started(&vsc->dev) == start) { > + if (!s->connected) { > return; > } > > - if (start) { > - int ret; > + if (vhost_dev_is_started(&vsc->dev) == should_start) { > + return; > + } > > - ret = vhost_scsi_common_start(vsc); > + if (should_start) { > + ret = vhost_user_scsi_start(s); > if (ret < 0) { > error_report("unable to start vhost-user-scsi: %s", strerror(-ret)); > - exit(1); > + qemu_chr_fe_disconnect(&vs->conf.chardev); > } > } else { > - vhost_scsi_common_stop(vsc); > + vhost_user_scsi_stop(s); > } > } > > @@ -89,14 +117,126 @@ static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) > { > } > > +static int vhost_user_scsi_connect(DeviceState *dev, Error **errp) > +{ > + VirtIODevice *vdev = VIRTIO_DEVICE(dev); > + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + int ret = 0; > + > + if (s->connected) { > + return 0; > + } > + s->connected = true; > + > + vsc->dev.num_queues = vs->conf.num_queues; > + vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; > + vsc->dev.vqs = s->vhost_vqs; > + vsc->dev.vq_index = 0; > + vsc->dev.backend_features = 0; > + > + ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0, > + errp); > + if (ret < 0) { > + return ret; > + } > + > + /* restore vhost state */ > + if (virtio_device_started(vdev, vdev->status)) { > + ret = vhost_user_scsi_start(s); > + if (ret < 0) { > + return ret; > + } > + } > + > + return 0; > +} > + > +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); > + > +static void vhost_user_scsi_disconnect(DeviceState *dev) > +{ > + VirtIODevice *vdev = VIRTIO_DEVICE(dev); > + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + > + if (!s->connected) { > + return; > + } > + s->connected = false; > + > + vhost_user_scsi_stop(s); > + > + vhost_dev_cleanup(&vsc->dev); > + > + /* Re-instate the event handler for new connections */ > + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, > + vhost_user_scsi_event, NULL, dev, NULL, true); > +} > + > +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) > +{ > + DeviceState *dev = opaque; > + VirtIODevice *vdev = VIRTIO_DEVICE(dev); > + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + Error *local_err = NULL; > + > + switch (event) { > + case CHR_EVENT_OPENED: > + if (vhost_user_scsi_connect(dev, &local_err) < 0) { > + error_report_err(local_err); > + qemu_chr_fe_disconnect(&vs->conf.chardev); > + return; > + } > + break; > + case CHR_EVENT_CLOSED: > + /* defer close until later to avoid circular close */ > + vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, > + vhost_user_scsi_disconnect); > + break; > + case CHR_EVENT_BREAK: > + case CHR_EVENT_MUX_IN: > + case CHR_EVENT_MUX_OUT: > + /* Ignore */ > + break; > + } > +} > + > +static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) > +{ > + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + int ret; > + > + s->connected = false; > + > + ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); > + if (ret < 0) { > + return ret; > + } > + > + ret = vhost_user_scsi_connect(dev, errp); > + if (ret < 0) { > + qemu_chr_fe_disconnect(&vs->conf.chardev); > + return ret; > + } > + assert(s->connected); > + > + return 0; > +} > + > static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) > { > VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > VHostUserSCSI *s = VHOST_USER_SCSI(dev); > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > - struct vhost_virtqueue *vqs = NULL; > Error *err = NULL; > int ret; > + int retries = VU_REALIZE_CONN_RETRIES; > > if (!vs->conf.chardev.chr) { > error_setg(errp, "vhost-user-scsi: missing chardev"); > @@ -115,18 +255,28 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) > goto free_virtio; > } > > - vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; > - vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); > - vsc->dev.vq_index = 0; > - vsc->dev.backend_features = 0; > - vqs = vsc->dev.vqs; > + vsc->inflight = g_new0(struct vhost_inflight, 1); > + s->vhost_vqs = g_new0(struct vhost_virtqueue, > + VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); > + > + assert(!*errp); > + do { > + if (*errp) { > + error_prepend(errp, "Reconnecting after error: "); > + error_report_err(*errp); > + *errp = NULL; > + } > + ret = vhost_user_scsi_realize_connect(s, errp); > + } while (ret < 0 && retries--); > > - ret = vhost_dev_init(&vsc->dev, &s->vhost_user, > - VHOST_BACKEND_TYPE_USER, 0, errp); > if (ret < 0) { > goto free_vhost; > } > > + /* we're fully initialized, now we can operate, so add the handler */ > + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, > + vhost_user_scsi_event, NULL, (void *)dev, > + NULL, true); > /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ > vsc->channel = 0; > vsc->lun = 0; > @@ -135,8 +285,12 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) > return; > > free_vhost: > + g_free(s->vhost_vqs); > + s->vhost_vqs = NULL; > + g_free(vsc->inflight); > + vsc->inflight = NULL; > vhost_user_cleanup(&s->vhost_user); > - g_free(vqs); > + > free_virtio: > virtio_scsi_common_unrealize(dev); > } > @@ -146,16 +300,23 @@ static void vhost_user_scsi_unrealize(DeviceState *dev) > VirtIODevice *vdev = VIRTIO_DEVICE(dev); > VHostUserSCSI *s = VHOST_USER_SCSI(dev); > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > - struct vhost_virtqueue *vqs = vsc->dev.vqs; > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > > /* This will stop the vhost backend. */ > vhost_user_scsi_set_status(vdev, 0); > + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, > + NULL, false); > > vhost_dev_cleanup(&vsc->dev); > - g_free(vqs); > + g_free(s->vhost_vqs); > + s->vhost_vqs = NULL; > + > + vhost_dev_free_inflight(vsc->inflight); > + g_free(vsc->inflight); > + vsc->inflight = NULL; > > - virtio_scsi_common_unrealize(dev); > vhost_user_cleanup(&s->vhost_user); > + virtio_scsi_common_unrealize(dev); > } > > static Property vhost_user_scsi_properties[] = { > diff --git a/include/hw/virtio/vhost-user-scsi.h b/include/hw/virtio/vhost-user-scsi.h > index 521b08e559..b405ec952a 100644 > --- a/include/hw/virtio/vhost-user-scsi.h > +++ b/include/hw/virtio/vhost-user-scsi.h > @@ -29,6 +29,10 @@ OBJECT_DECLARE_SIMPLE_TYPE(VHostUserSCSI, VHOST_USER_SCSI) > struct VHostUserSCSI { > VHostSCSICommon parent_obj; > VhostUserState vhost_user; > + bool connected; > + bool started_vu; > + > + struct vhost_virtqueue *vhost_vqs; > }; > > #endif /* VHOST_USER_SCSI_H */ > -- > 2.41.0 >
Li Feng <fengli@smartx.com> writes: > If the backend crashes and restarts, the device is broken. > This patch adds reconnect for vhost-user-scsi. > > Tested with spdk backend. > > Signed-off-by: Li Feng <fengli@smartx.com> > --- > hw/scsi/vhost-user-scsi.c | 199 +++++++++++++++++++++++++--- > include/hw/virtio/vhost-user-scsi.h | 4 + > 2 files changed, 184 insertions(+), 19 deletions(-) > > diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c > index ee99b19e7a..5bf012461b 100644 > --- a/hw/scsi/vhost-user-scsi.c > +++ b/hw/scsi/vhost-user-scsi.c > @@ -43,26 +43,54 @@ enum VhostUserProtocolFeature { > VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13, > }; > > +static int vhost_user_scsi_start(VHostUserSCSI *s) > +{ > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + int ret; > + > + ret = vhost_scsi_common_start(vsc); > + s->started_vu = (ret < 0 ? false : true); > + > + return ret; > +} > + > +static void vhost_user_scsi_stop(VHostUserSCSI *s) > +{ > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + > + if (!s->started_vu) { > + return; > + } > + s->started_vu = false; > + > + vhost_scsi_common_stop(vsc); > +} > + > static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status) > { > VHostUserSCSI *s = (VHostUserSCSI *)vdev; > + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > - bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running; > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + bool should_start = virtio_device_should_start(vdev, status); > + int ret; > > - if (vhost_dev_is_started(&vsc->dev) == start) { > + if (!s->connected) { > return; > } > > - if (start) { > - int ret; > + if (vhost_dev_is_started(&vsc->dev) == should_start) { > + return; > + } > > - ret = vhost_scsi_common_start(vsc); > + if (should_start) { > + ret = vhost_user_scsi_start(s); > if (ret < 0) { > error_report("unable to start vhost-user-scsi: %s", strerror(-ret)); > - exit(1); > + qemu_chr_fe_disconnect(&vs->conf.chardev); > } > } else { > - vhost_scsi_common_stop(vsc); > + vhost_user_scsi_stop(s); > } > } > > @@ -89,14 +117,126 @@ static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) > { > } > > +static int vhost_user_scsi_connect(DeviceState *dev, Error **errp) > +{ > + VirtIODevice *vdev = VIRTIO_DEVICE(dev); > + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + int ret = 0; > + > + if (s->connected) { > + return 0; > + } > + s->connected = true; > + > + vsc->dev.num_queues = vs->conf.num_queues; > + vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; > + vsc->dev.vqs = s->vhost_vqs; > + vsc->dev.vq_index = 0; > + vsc->dev.backend_features = 0; > + > + ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0, > + errp); > + if (ret < 0) { > + return ret; > + } > + > + /* restore vhost state */ > + if (virtio_device_started(vdev, vdev->status)) { > + ret = vhost_user_scsi_start(s); > + if (ret < 0) { > + return ret; > + } Fails without setting an error, violating the function's (tacit) postcondition. Callers: * vhost_user_scsi_event() Dereferences the null error and crashes. * vhost_user_scsi_realize_connect() Also fails without setting an error. Caller: - vhost_user_scsi_realize() 1. Doesn't emit the "Reconnecting after error: " message. See also below. 2. Succeeds instead of failing! > + } > + > + return 0; > +} > + > +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); > + > +static void vhost_user_scsi_disconnect(DeviceState *dev) > +{ > + VirtIODevice *vdev = VIRTIO_DEVICE(dev); > + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + > + if (!s->connected) { > + return; > + } > + s->connected = false; > + > + vhost_user_scsi_stop(s); > + > + vhost_dev_cleanup(&vsc->dev); > + > + /* Re-instate the event handler for new connections */ > + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, > + vhost_user_scsi_event, NULL, dev, NULL, true); > +} > + > +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) > +{ > + DeviceState *dev = opaque; > + VirtIODevice *vdev = VIRTIO_DEVICE(dev); > + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + Error *local_err = NULL; > + > + switch (event) { > + case CHR_EVENT_OPENED: > + if (vhost_user_scsi_connect(dev, &local_err) < 0) { > + error_report_err(local_err); > + qemu_chr_fe_disconnect(&vs->conf.chardev); > + return; > + } > + break; > + case CHR_EVENT_CLOSED: > + /* defer close until later to avoid circular close */ > + vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, > + vhost_user_scsi_disconnect); > + break; > + case CHR_EVENT_BREAK: > + case CHR_EVENT_MUX_IN: > + case CHR_EVENT_MUX_OUT: > + /* Ignore */ > + break; > + } > +} > + > +static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) > +{ > + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > + int ret; > + > + s->connected = false; > + > + ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); > + if (ret < 0) { > + return ret; > + } > + > + ret = vhost_user_scsi_connect(dev, errp); > + if (ret < 0) { > + qemu_chr_fe_disconnect(&vs->conf.chardev); > + return ret; > + } > + assert(s->connected); > + > + return 0; > +} > + > static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) > { > VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > VHostUserSCSI *s = VHOST_USER_SCSI(dev); > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > - struct vhost_virtqueue *vqs = NULL; > Error *err = NULL; > int ret; > + int retries = VU_REALIZE_CONN_RETRIES; > > if (!vs->conf.chardev.chr) { > error_setg(errp, "vhost-user-scsi: missing chardev"); > @@ -115,18 +255,28 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) > goto free_virtio; > } > > - vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; > - vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); > - vsc->dev.vq_index = 0; > - vsc->dev.backend_features = 0; > - vqs = vsc->dev.vqs; > + vsc->inflight = g_new0(struct vhost_inflight, 1); > + s->vhost_vqs = g_new0(struct vhost_virtqueue, > + VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); > + > + assert(!*errp); Dereferencing *errp is wrong. Quoting qapi/error.h's big comment: * = Why, when and how to use ERRP_GUARD() = * * Without ERRP_GUARD(), use of the @errp parameter is restricted: * - It must not be dereferenced, because it may be null. * - It should not be passed to error_prepend() or * error_append_hint(), because that doesn't work with &error_fatal. * ERRP_GUARD() lifts these restrictions. See there for how to use ERRP_GUARD(). > + do { > + if (*errp) { > + error_prepend(errp, "Reconnecting after error: "); > + error_report_err(*errp); > + *errp = NULL; > + } > + ret = vhost_user_scsi_realize_connect(s, errp); > + } while (ret < 0 && retries--); Reports "Reconnecting ..." to the HMP monitor when in HMP context, else to stderr. I.e. reports to stderr when we're in QMP context. Is this really what we want? > > - ret = vhost_dev_init(&vsc->dev, &s->vhost_user, > - VHOST_BACKEND_TYPE_USER, 0, errp); > if (ret < 0) { > goto free_vhost; > } > > + /* we're fully initialized, now we can operate, so add the handler */ > + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, > + vhost_user_scsi_event, NULL, (void *)dev, > + NULL, true); > /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ > vsc->channel = 0; > vsc->lun = 0; > @@ -135,8 +285,12 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) > return; > > free_vhost: > + g_free(s->vhost_vqs); > + s->vhost_vqs = NULL; > + g_free(vsc->inflight); > + vsc->inflight = NULL; > vhost_user_cleanup(&s->vhost_user); > - g_free(vqs); > + > free_virtio: > virtio_scsi_common_unrealize(dev); > } > @@ -146,16 +300,23 @@ static void vhost_user_scsi_unrealize(DeviceState *dev) > VirtIODevice *vdev = VIRTIO_DEVICE(dev); > VHostUserSCSI *s = VHOST_USER_SCSI(dev); > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); > - struct vhost_virtqueue *vqs = vsc->dev.vqs; > + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); > > /* This will stop the vhost backend. */ > vhost_user_scsi_set_status(vdev, 0); > + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, > + NULL, false); > > vhost_dev_cleanup(&vsc->dev); > - g_free(vqs); > + g_free(s->vhost_vqs); > + s->vhost_vqs = NULL; > + > + vhost_dev_free_inflight(vsc->inflight); > + g_free(vsc->inflight); > + vsc->inflight = NULL; > > - virtio_scsi_common_unrealize(dev); > vhost_user_cleanup(&s->vhost_user); > + virtio_scsi_common_unrealize(dev); > } > > static Property vhost_user_scsi_properties[] = { > diff --git a/include/hw/virtio/vhost-user-scsi.h b/include/hw/virtio/vhost-user-scsi.h > index 521b08e559..b405ec952a 100644 > --- a/include/hw/virtio/vhost-user-scsi.h > +++ b/include/hw/virtio/vhost-user-scsi.h > @@ -29,6 +29,10 @@ OBJECT_DECLARE_SIMPLE_TYPE(VHostUserSCSI, VHOST_USER_SCSI) > struct VHostUserSCSI { > VHostSCSICommon parent_obj; > VhostUserState vhost_user; > + bool connected; > + bool started_vu; > + > + struct vhost_virtqueue *vhost_vqs; > }; > > #endif /* VHOST_USER_SCSI_H */
> On 1 Sep 2023, at 8:00 PM, Markus Armbruster <armbru@redhat.com> wrote: > > Li Feng <fengli@smartx.com <mailto:fengli@smartx.com>> writes: > >> If the backend crashes and restarts, the device is broken. >> This patch adds reconnect for vhost-user-scsi. >> >> Tested with spdk backend. >> >> Signed-off-by: Li Feng <fengli@smartx.com> >> --- >> hw/scsi/vhost-user-scsi.c | 199 +++++++++++++++++++++++++--- >> include/hw/virtio/vhost-user-scsi.h | 4 + >> 2 files changed, 184 insertions(+), 19 deletions(-) >> >> diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c >> index ee99b19e7a..5bf012461b 100644 >> --- a/hw/scsi/vhost-user-scsi.c >> +++ b/hw/scsi/vhost-user-scsi.c >> @@ -43,26 +43,54 @@ enum VhostUserProtocolFeature { >> VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13, >> }; >> >> +static int vhost_user_scsi_start(VHostUserSCSI *s) >> +{ >> + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> + int ret; >> + >> + ret = vhost_scsi_common_start(vsc); >> + s->started_vu = (ret < 0 ? false : true); >> + >> + return ret; >> +} >> + >> +static void vhost_user_scsi_stop(VHostUserSCSI *s) >> +{ >> + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> + >> + if (!s->started_vu) { >> + return; >> + } >> + s->started_vu = false; >> + >> + vhost_scsi_common_stop(vsc); >> +} >> + >> static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status) >> { >> VHostUserSCSI *s = (VHostUserSCSI *)vdev; >> + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; >> VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> - bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running; >> + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> + bool should_start = virtio_device_should_start(vdev, status); >> + int ret; >> >> - if (vhost_dev_is_started(&vsc->dev) == start) { >> + if (!s->connected) { >> return; >> } >> >> - if (start) { >> - int ret; >> + if (vhost_dev_is_started(&vsc->dev) == should_start) { >> + return; >> + } >> >> - ret = vhost_scsi_common_start(vsc); >> + if (should_start) { >> + ret = vhost_user_scsi_start(s); >> if (ret < 0) { >> error_report("unable to start vhost-user-scsi: %s", strerror(-ret)); >> - exit(1); >> + qemu_chr_fe_disconnect(&vs->conf.chardev); >> } >> } else { >> - vhost_scsi_common_stop(vsc); >> + vhost_user_scsi_stop(s); >> } >> } >> >> @@ -89,14 +117,126 @@ static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) >> { >> } >> >> +static int vhost_user_scsi_connect(DeviceState *dev, Error **errp) >> +{ >> + VirtIODevice *vdev = VIRTIO_DEVICE(dev); >> + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); >> + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> + int ret = 0; >> + >> + if (s->connected) { >> + return 0; >> + } >> + s->connected = true; >> + >> + vsc->dev.num_queues = vs->conf.num_queues; >> + vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; >> + vsc->dev.vqs = s->vhost_vqs; >> + vsc->dev.vq_index = 0; >> + vsc->dev.backend_features = 0; >> + >> + ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0, >> + errp); >> + if (ret < 0) { >> + return ret; >> + } >> + >> + /* restore vhost state */ >> + if (virtio_device_started(vdev, vdev->status)) { >> + ret = vhost_user_scsi_start(s); >> + if (ret < 0) { >> + return ret; >> + } > > Fails without setting an error, violating the function's (tacit) > postcondition. Callers: > > * vhost_user_scsi_event() > > Dereferences the null error and crashes. > > * vhost_user_scsi_realize_connect() > > Also fails without setting an error. Caller: > > - vhost_user_scsi_realize() > > 1. Doesn't emit the "Reconnecting after error: " message. See > also below. > > 2. Succeeds instead of failing! Ack. > >> + } >> + >> + return 0; >> +} >> + >> +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); >> + >> +static void vhost_user_scsi_disconnect(DeviceState *dev) >> +{ >> + VirtIODevice *vdev = VIRTIO_DEVICE(dev); >> + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); >> + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> + >> + if (!s->connected) { >> + return; >> + } >> + s->connected = false; >> + >> + vhost_user_scsi_stop(s); >> + >> + vhost_dev_cleanup(&vsc->dev); >> + >> + /* Re-instate the event handler for new connections */ >> + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, >> + vhost_user_scsi_event, NULL, dev, NULL, true); >> +} >> + >> +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) >> +{ >> + DeviceState *dev = opaque; >> + VirtIODevice *vdev = VIRTIO_DEVICE(dev); >> + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); >> + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> + Error *local_err = NULL; >> + >> + switch (event) { >> + case CHR_EVENT_OPENED: >> + if (vhost_user_scsi_connect(dev, &local_err) < 0) { >> + error_report_err(local_err); >> + qemu_chr_fe_disconnect(&vs->conf.chardev); >> + return; >> + } >> + break; >> + case CHR_EVENT_CLOSED: >> + /* defer close until later to avoid circular close */ >> + vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, >> + vhost_user_scsi_disconnect); >> + break; >> + case CHR_EVENT_BREAK: >> + case CHR_EVENT_MUX_IN: >> + case CHR_EVENT_MUX_OUT: >> + /* Ignore */ >> + break; >> + } >> +} >> + >> +static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) >> +{ >> + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; >> + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> + int ret; >> + >> + s->connected = false; >> + >> + ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); >> + if (ret < 0) { >> + return ret; >> + } >> + >> + ret = vhost_user_scsi_connect(dev, errp); >> + if (ret < 0) { >> + qemu_chr_fe_disconnect(&vs->conf.chardev); >> + return ret; >> + } >> + assert(s->connected); >> + >> + return 0; >> +} >> + >> static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) >> { >> VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> VHostUserSCSI *s = VHOST_USER_SCSI(dev); >> VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> - struct vhost_virtqueue *vqs = NULL; >> Error *err = NULL; >> int ret; >> + int retries = VU_REALIZE_CONN_RETRIES; >> >> if (!vs->conf.chardev.chr) { >> error_setg(errp, "vhost-user-scsi: missing chardev"); >> @@ -115,18 +255,28 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) >> goto free_virtio; >> } >> >> - vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; >> - vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); >> - vsc->dev.vq_index = 0; >> - vsc->dev.backend_features = 0; >> - vqs = vsc->dev.vqs; >> + vsc->inflight = g_new0(struct vhost_inflight, 1); >> + s->vhost_vqs = g_new0(struct vhost_virtqueue, >> + VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); >> + >> + assert(!*errp); > > Dereferencing *errp is wrong. Quoting qapi/error.h's big comment: > > * = Why, when and how to use ERRP_GUARD() = > * > * Without ERRP_GUARD(), use of the @errp parameter is restricted: > * - It must not be dereferenced, because it may be null. > * - It should not be passed to error_prepend() or > * error_append_hint(), because that doesn't work with &error_fatal. > * ERRP_GUARD() lifts these restrictions. > > See there for how to use ERRP_GUARD(). Thanks, good catch. I have understood this knowledge. > >> + do { >> + if (*errp) { >> + error_prepend(errp, "Reconnecting after error: "); >> + error_report_err(*errp); >> + *errp = NULL; >> + } >> + ret = vhost_user_scsi_realize_connect(s, errp); >> + } while (ret < 0 && retries--); > > Reports "Reconnecting ..." to the HMP monitor when in HMP context, else > to stderr. I.e. reports to stderr when we're in QMP context. Is this > really what we want? The vhost-user-blk has the same code, so just keep it the same here is a good idea? > >> >> - ret = vhost_dev_init(&vsc->dev, &s->vhost_user, >> - VHOST_BACKEND_TYPE_USER, 0, errp); >> if (ret < 0) { >> goto free_vhost; >> } >> >> + /* we're fully initialized, now we can operate, so add the handler */ >> + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, >> + vhost_user_scsi_event, NULL, (void *)dev, >> + NULL, true); >> /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ >> vsc->channel = 0; >> vsc->lun = 0; >> @@ -135,8 +285,12 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) >> return; >> >> free_vhost: >> + g_free(s->vhost_vqs); >> + s->vhost_vqs = NULL; >> + g_free(vsc->inflight); >> + vsc->inflight = NULL; >> vhost_user_cleanup(&s->vhost_user); >> - g_free(vqs); >> + >> free_virtio: >> virtio_scsi_common_unrealize(dev); >> } >> @@ -146,16 +300,23 @@ static void vhost_user_scsi_unrealize(DeviceState *dev) >> VirtIODevice *vdev = VIRTIO_DEVICE(dev); >> VHostUserSCSI *s = VHOST_USER_SCSI(dev); >> VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); >> - struct vhost_virtqueue *vqs = vsc->dev.vqs; >> + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); >> >> /* This will stop the vhost backend. */ >> vhost_user_scsi_set_status(vdev, 0); >> + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, >> + NULL, false); >> >> vhost_dev_cleanup(&vsc->dev); >> - g_free(vqs); >> + g_free(s->vhost_vqs); >> + s->vhost_vqs = NULL; >> + >> + vhost_dev_free_inflight(vsc->inflight); >> + g_free(vsc->inflight); >> + vsc->inflight = NULL; >> >> - virtio_scsi_common_unrealize(dev); >> vhost_user_cleanup(&s->vhost_user); >> + virtio_scsi_common_unrealize(dev); >> } >> >> static Property vhost_user_scsi_properties[] = { >> diff --git a/include/hw/virtio/vhost-user-scsi.h b/include/hw/virtio/vhost-user-scsi.h >> index 521b08e559..b405ec952a 100644 >> --- a/include/hw/virtio/vhost-user-scsi.h >> +++ b/include/hw/virtio/vhost-user-scsi.h >> @@ -29,6 +29,10 @@ OBJECT_DECLARE_SIMPLE_TYPE(VHostUserSCSI, VHOST_USER_SCSI) >> struct VHostUserSCSI { >> VHostSCSICommon parent_obj; >> VhostUserState vhost_user; >> + bool connected; >> + bool started_vu; >> + >> + struct vhost_virtqueue *vhost_vqs; >> }; >> >> #endif /* VHOST_USER_SCSI_H */
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c index ee99b19e7a..5bf012461b 100644 --- a/hw/scsi/vhost-user-scsi.c +++ b/hw/scsi/vhost-user-scsi.c @@ -43,26 +43,54 @@ enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13, }; +static int vhost_user_scsi_start(VHostUserSCSI *s) +{ + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); + int ret; + + ret = vhost_scsi_common_start(vsc); + s->started_vu = (ret < 0 ? false : true); + + return ret; +} + +static void vhost_user_scsi_stop(VHostUserSCSI *s) +{ + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); + + if (!s->started_vu) { + return; + } + s->started_vu = false; + + vhost_scsi_common_stop(vsc); +} + static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status) { VHostUserSCSI *s = (VHostUserSCSI *)vdev; + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); - bool start = (status & VIRTIO_CONFIG_S_DRIVER_OK) && vdev->vm_running; + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); + bool should_start = virtio_device_should_start(vdev, status); + int ret; - if (vhost_dev_is_started(&vsc->dev) == start) { + if (!s->connected) { return; } - if (start) { - int ret; + if (vhost_dev_is_started(&vsc->dev) == should_start) { + return; + } - ret = vhost_scsi_common_start(vsc); + if (should_start) { + ret = vhost_user_scsi_start(s); if (ret < 0) { error_report("unable to start vhost-user-scsi: %s", strerror(-ret)); - exit(1); + qemu_chr_fe_disconnect(&vs->conf.chardev); } } else { - vhost_scsi_common_stop(vsc); + vhost_user_scsi_stop(s); } } @@ -89,14 +117,126 @@ static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) { } +static int vhost_user_scsi_connect(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); + int ret = 0; + + if (s->connected) { + return 0; + } + s->connected = true; + + vsc->dev.num_queues = vs->conf.num_queues; + vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; + vsc->dev.vqs = s->vhost_vqs; + vsc->dev.vq_index = 0; + vsc->dev.backend_features = 0; + + ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0, + errp); + if (ret < 0) { + return ret; + } + + /* restore vhost state */ + if (virtio_device_started(vdev, vdev->status)) { + ret = vhost_user_scsi_start(s); + if (ret < 0) { + return ret; + } + } + + return 0; +} + +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event); + +static void vhost_user_scsi_disconnect(DeviceState *dev) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); + + if (!s->connected) { + return; + } + s->connected = false; + + vhost_user_scsi_stop(s); + + vhost_dev_cleanup(&vsc->dev); + + /* Re-instate the event handler for new connections */ + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, + vhost_user_scsi_event, NULL, dev, NULL, true); +} + +static void vhost_user_scsi_event(void *opaque, QEMUChrEvent event) +{ + DeviceState *dev = opaque; + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VHostUserSCSI *s = VHOST_USER_SCSI(vdev); + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); + Error *local_err = NULL; + + switch (event) { + case CHR_EVENT_OPENED: + if (vhost_user_scsi_connect(dev, &local_err) < 0) { + error_report_err(local_err); + qemu_chr_fe_disconnect(&vs->conf.chardev); + return; + } + break; + case CHR_EVENT_CLOSED: + /* defer close until later to avoid circular close */ + vhost_user_async_close(dev, &vs->conf.chardev, &vsc->dev, + vhost_user_scsi_disconnect); + break; + case CHR_EVENT_BREAK: + case CHR_EVENT_MUX_IN: + case CHR_EVENT_MUX_OUT: + /* Ignore */ + break; + } +} + +static int vhost_user_scsi_realize_connect(VHostUserSCSI *s, Error **errp) +{ + DeviceState *dev = &s->parent_obj.parent_obj.parent_obj.parent_obj; + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); + int ret; + + s->connected = false; + + ret = qemu_chr_fe_wait_connected(&vs->conf.chardev, errp); + if (ret < 0) { + return ret; + } + + ret = vhost_user_scsi_connect(dev, errp); + if (ret < 0) { + qemu_chr_fe_disconnect(&vs->conf.chardev); + return ret; + } + assert(s->connected); + + return 0; +} + static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) { VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); VHostUserSCSI *s = VHOST_USER_SCSI(dev); VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); - struct vhost_virtqueue *vqs = NULL; Error *err = NULL; int ret; + int retries = VU_REALIZE_CONN_RETRIES; if (!vs->conf.chardev.chr) { error_setg(errp, "vhost-user-scsi: missing chardev"); @@ -115,18 +255,28 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) goto free_virtio; } - vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; - vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); - vsc->dev.vq_index = 0; - vsc->dev.backend_features = 0; - vqs = vsc->dev.vqs; + vsc->inflight = g_new0(struct vhost_inflight, 1); + s->vhost_vqs = g_new0(struct vhost_virtqueue, + VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues); + + assert(!*errp); + do { + if (*errp) { + error_prepend(errp, "Reconnecting after error: "); + error_report_err(*errp); + *errp = NULL; + } + ret = vhost_user_scsi_realize_connect(s, errp); + } while (ret < 0 && retries--); - ret = vhost_dev_init(&vsc->dev, &s->vhost_user, - VHOST_BACKEND_TYPE_USER, 0, errp); if (ret < 0) { goto free_vhost; } + /* we're fully initialized, now we can operate, so add the handler */ + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, + vhost_user_scsi_event, NULL, (void *)dev, + NULL, true); /* Channel and lun both are 0 for bootable vhost-user-scsi disk */ vsc->channel = 0; vsc->lun = 0; @@ -135,8 +285,12 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp) return; free_vhost: + g_free(s->vhost_vqs); + s->vhost_vqs = NULL; + g_free(vsc->inflight); + vsc->inflight = NULL; vhost_user_cleanup(&s->vhost_user); - g_free(vqs); + free_virtio: virtio_scsi_common_unrealize(dev); } @@ -146,16 +300,23 @@ static void vhost_user_scsi_unrealize(DeviceState *dev) VirtIODevice *vdev = VIRTIO_DEVICE(dev); VHostUserSCSI *s = VHOST_USER_SCSI(dev); VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); - struct vhost_virtqueue *vqs = vsc->dev.vqs; + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); /* This will stop the vhost backend. */ vhost_user_scsi_set_status(vdev, 0); + qemu_chr_fe_set_handlers(&vs->conf.chardev, NULL, NULL, NULL, NULL, NULL, + NULL, false); vhost_dev_cleanup(&vsc->dev); - g_free(vqs); + g_free(s->vhost_vqs); + s->vhost_vqs = NULL; + + vhost_dev_free_inflight(vsc->inflight); + g_free(vsc->inflight); + vsc->inflight = NULL; - virtio_scsi_common_unrealize(dev); vhost_user_cleanup(&s->vhost_user); + virtio_scsi_common_unrealize(dev); } static Property vhost_user_scsi_properties[] = { diff --git a/include/hw/virtio/vhost-user-scsi.h b/include/hw/virtio/vhost-user-scsi.h index 521b08e559..b405ec952a 100644 --- a/include/hw/virtio/vhost-user-scsi.h +++ b/include/hw/virtio/vhost-user-scsi.h @@ -29,6 +29,10 @@ OBJECT_DECLARE_SIMPLE_TYPE(VHostUserSCSI, VHOST_USER_SCSI) struct VHostUserSCSI { VHostSCSICommon parent_obj; VhostUserState vhost_user; + bool connected; + bool started_vu; + + struct vhost_virtqueue *vhost_vqs; }; #endif /* VHOST_USER_SCSI_H */
If the backend crashes and restarts, the device is broken. This patch adds reconnect for vhost-user-scsi. Tested with spdk backend. Signed-off-by: Li Feng <fengli@smartx.com> --- hw/scsi/vhost-user-scsi.c | 199 +++++++++++++++++++++++++--- include/hw/virtio/vhost-user-scsi.h | 4 + 2 files changed, 184 insertions(+), 19 deletions(-)