Sorry, the reply is late due to being on vacation for half a month.
On Fri, Sep 29, 2023 at 8:55 AM Raphael Norwitz
<raphael.norw...@nutanix.com> wrote:
>
> One comment on the logging stuff in vhost-scsi. As far as I can tell the
> logging in vhost-user-scsi looks good.
>
> Markus - does this look better to you? Otherwise do you think we should also
> fix up the vhost-user-blk realize function?
>
> > On Sep 22, 2023, at 7:46 AM, Li Feng <fen...@smartx.com> wrote:
> >
> > If the backend crashes and restarts, the device is broken.
> > This patch adds reconnect for vhost-user-scsi.
> >
> > This patch also improves the error messages, and reports some silent errors.
> >
> > Tested with spdk backend.
> >
> > Signed-off-by: Li Feng <fen...@smartx.com>
> > ---
> > hw/scsi/vhost-scsi-common.c | 16 +-
> > hw/scsi/vhost-scsi.c | 5 +-
> > hw/scsi/vhost-user-scsi.c | 204 +++++++++++++++++++++++---
> > include/hw/virtio/vhost-scsi-common.h | 2 +-
> > include/hw/virtio/vhost-user-scsi.h | 4 +
> > 5 files changed, 201 insertions(+), 30 deletions(-)
> >
> > diff --git a/hw/scsi/vhost-scsi-common.c b/hw/scsi/vhost-scsi-common.c
> > index a61cd0e907..4c8637045d 100644
> > --- a/hw/scsi/vhost-scsi-common.c
> > +++ b/hw/scsi/vhost-scsi-common.c
> > @@ -16,6 +16,7 @@
> > */
> >
> > #include "qemu/osdep.h"
> > +#include "qapi/error.h"
> > #include "qemu/error-report.h"
> > #include "qemu/module.h"
> > #include "hw/virtio/vhost.h"
> > @@ -25,7 +26,7 @@
> > #include "hw/virtio/virtio-access.h"
> > #include "hw/fw-path-provider.h"
> >
> > -int vhost_scsi_common_start(VHostSCSICommon *vsc)
> > +int vhost_scsi_common_start(VHostSCSICommon *vsc, Error **errp)
> > {
> > int ret, i;
> > VirtIODevice *vdev = VIRTIO_DEVICE(vsc);
> > @@ -35,18 +36,19 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> > VirtIOSCSICommon *vs = (VirtIOSCSICommon *)vsc;
> >
> > if (!k->set_guest_notifiers) {
> > - error_report("binding does not support guest notifiers");
> > + error_setg(errp, "binding does not support guest notifiers");
> > return -ENOSYS;
> > }
> >
> > ret = vhost_dev_enable_notifiers(&vsc->dev, vdev);
> > if (ret < 0) {
> > + error_setg_errno(errp, -ret, "Error enabling host notifiers");
> > return ret;
> > }
> >
> > ret = k->set_guest_notifiers(qbus->parent, vsc->dev.nvqs, true);
> > if (ret < 0) {
> > - error_report("Error binding guest notifier");
> > + error_setg_errno(errp, -ret, "Error binding guest notifier");
> > goto err_host_notifiers;
> > }
> >
> > @@ -54,7 +56,7 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> >
> > ret = vhost_dev_prepare_inflight(&vsc->dev, vdev);
> > if (ret < 0) {
> > - error_report("Error setting inflight format: %d", -ret);
> > + error_setg_errno(errp, -ret, "Error setting inflight format");
> > goto err_guest_notifiers;
> > }
> >
> > @@ -64,21 +66,21 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> > vs->conf.virtqueue_size,
> > vsc->inflight);
> > if (ret < 0) {
> > - error_report("Error getting inflight: %d", -ret);
> > + error_setg_errno(errp, -ret, "Error getting inflight");
> > goto err_guest_notifiers;
> > }
> > }
> >
> > ret = vhost_dev_set_inflight(&vsc->dev, vsc->inflight);
> > if (ret < 0) {
> > - error_report("Error setting inflight: %d", -ret);
> > + error_setg_errno(errp, -ret, "Error setting inflight");
> > goto err_guest_notifiers;
> > }
> > }
> >
> > ret = vhost_dev_start(&vsc->dev, vdev, true);
> > if (ret < 0) {
> > - error_report("Error start vhost dev");
> > + error_setg_errno(errp, -ret, "Error starting vhost dev");
> > goto err_guest_notifiers;
> > }
> >
> > diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
> > index 443f67daa4..01a3ab4277 100644
> > --- a/hw/scsi/vhost-scsi.c
> > +++ b/hw/scsi/vhost-scsi.c
> > @@ -75,6 +75,7 @@ static int vhost_scsi_start(VHostSCSI *s)
> > int ret, abi_version;
> > VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
> > const VhostOps *vhost_ops = vsc->dev.vhost_ops;
> > + Error *local_err = NULL;
> >
> > ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version);
> > if (ret < 0) {
> > @@ -88,14 +89,14 @@ static int vhost_scsi_start(VHostSCSI *s)
> > return -ENOSYS;
> > }
> >
> > - ret = vhost_scsi_common_start(vsc);
> > + ret = vhost_scsi_common_start(vsc, &local_err);
> > if (ret < 0) {
>
> Why aren’t you reporting the error here?
I will add reporting the error in the next version.
>
> > return ret;
> > }
> >
> > ret = vhost_scsi_set_endpoint(s);
> > if (ret < 0) {
> > - error_report("Error setting vhost-scsi endpoint");
> > + error_reportf_err(local_err, "Error setting vhost-scsi endpoint");
> > vhost_scsi_common_stop(vsc);
> > }
> >
> > diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
> > index ee99b19e7a..dc109154ad 100644
> > --- a/hw/scsi/vhost-user-scsi.c
> > +++ b/hw/scsi/vhost-user-scsi.c
> > @@ -43,26 +43,56 @@ enum VhostUserProtocolFeature {
> > VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
> > };
> >
> > +static int vhost_user_scsi_start(VHostUserSCSI *s, Error **errp)
> > +{
> > + VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
> > + int ret;
> > +
> > + ret = vhost_scsi_common_start(vsc, errp);
> > + 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);
> > + Error *local_err = NULL;
> > + 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, &local_err);
> > if (ret < 0) {
> > - error_report("unable to start vhost-user-scsi: %s",
> > strerror(-ret));
> > - exit(1);
> > + error_reportf_err(local_err, "unable to start vhost-user-scsi:
> > %s",
> > + strerror(-ret));
> > + qemu_chr_fe_disconnect(&vs->conf.chardev);
> > }
> > } else {
> > - vhost_scsi_common_stop(vsc);
> > + vhost_user_scsi_stop(s);
> > }
> > }
> >
> > @@ -89,14 +119,127 @@ 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, errp);
> > + 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)
> > {
> > + ERRP_GUARD();
> > 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 +258,28 @@ 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 +288,12 @@ 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 +303,23 @@ 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-scsi-common.h
> > b/include/hw/virtio/vhost-scsi-common.h
> > index 18f115527c..c5d2c09455 100644
> > --- a/include/hw/virtio/vhost-scsi-common.h
> > +++ b/include/hw/virtio/vhost-scsi-common.h
> > @@ -39,7 +39,7 @@ struct VHostSCSICommon {
> > struct vhost_inflight *inflight;
> > };
> >
> > -int vhost_scsi_common_start(VHostSCSICommon *vsc);
> > +int vhost_scsi_common_start(VHostSCSICommon *vsc, Error **errp);
> > void vhost_scsi_common_stop(VHostSCSICommon *vsc);
> > char *vhost_scsi_common_get_fw_dev_path(FWPathProvider *p, BusState *bus,
> > DeviceState *dev);
> > 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
> >
>
