Re: [Qemu-devel] [PATCH 6/9] vhost-scsi: new device supporting the tcm_vhost Linux kernel module

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

于 2013-4-19 22:24, Paolo Bonzini 写道:
> From: Nicholas Bellinger <nab@linux-iscsi.org>
> 
> The WWPN specified in configfs is passed to "-device vhost-scsi-pci".
> The tgpt field of the SET_ENDPOINT ioctl is obsolete now, so it is not
> available from the QEMU command-line.  Instead, I hardcode it to zero.
> 
Hi, Paolo
  Any document about how to config it correctly in configfs, before
invoking qemu with the WWPN number?


> Changes in Patch-v2:
>     - Add vhost_scsi_get_features() in order to determine feature bits
>       supports by host kernel (mst + nab)
>     - Re-enable usage of DEFINE_VIRTIO_COMMON_FEATURES, and allow
>       EVENT_IDX to be disabled by host in vhost_scsi_get_features()
>     - Drop unused hotplug bit in DEFINE_VHOST_SCSI_PROPERTIES
> 
> Changes in Patch-v1:
>     - Set event_idx=off by default (nab, thanks asias)
>     - Disable hotplug feature bit for v3.9 tcm_vhost kernel code, need to
>       re-enable in v3.10 (nab)
>     - Update to latest qemu.git/master HEAD
> 
> Changes in WIP-V3:
>     - Drop ioeventfd vhost_scsi_properties (asias, thanks stefanha)
>     - Add CONFIG_VHOST_SCSI (asias, thanks stefanha)
>     - Add hotplug feature bit
> 
> Changes in WIP-V2:
>     - Add backend guest masking support (nab)
>     - Bump ABI_VERSION to 1 (nab)
>     - Set up set_guest_notifiers (asias)
>     - Set up vs->dev.vq_index (asias)
>     - Drop vs->vs.vdev.{set,clear}_vhost_endpoint (asias)
>     - Drop VIRTIO_CONFIG_S_DRIVER check in vhost_scsi_set_status (asias)
> 
> Howto:
>     Use the latest seabios, at least commit b44a7be17b
>     git clone git://git.seabios.org/seabios.git
>     make
>     cp out/bios.bin /usr/share/qemu/bios.bin
>     qemu -device vhost-scsi-pci,wwpn=naa.6001405bd4e8476d
> ...
> 
> Cc: Michael S. Tsirkin <mst@redhat.com>
> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
> Signed-off-by: Asias He <asias@redhat.com>
> [ Rebase on top of VirtIOSCSICommon patch, fix bugs in feature
>    negotiation and irqfd masking - Paolo ]
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   configure                       |  10 ++
>   hw/scsi/Makefile.objs           |   6 +-
>   hw/scsi/vhost-scsi.c            | 288 ++++++++++++++++++++++++++++++++++++++++
>   include/hw/virtio/vhost-scsi.h  |  73 ++++++++++
>   include/hw/virtio/virtio-scsi.h |   2 +
>   5 files changed, 378 insertions(+), 1 deletion(-)
>   create mode 100644 hw/scsi/vhost-scsi.c
>   create mode 100644 include/hw/virtio/vhost-scsi.h
> 
> diff --git a/configure b/configure
> index ed49f91..51a6c56 100755
> --- a/configure
> +++ b/configure
> @@ -179,6 +179,7 @@ libattr=""
>   xfs=""
> 
>   vhost_net="no"
> +vhost_scsi="no"
>   kvm="no"
>   gprof="no"
>   debug_tcg="no"
> @@ -543,6 +544,7 @@ Haiku)
>     usb="linux"
>     kvm="yes"
>     vhost_net="yes"
> +  vhost_scsi="yes"
>     if [ "$cpu" = "i386" -o "$cpu" = "x86_64" ] ; then
>       audio_possible_drivers="$audio_possible_drivers fmod"
>     fi
> @@ -870,6 +872,10 @@ for opt do
>     ;;
>     --enable-vhost-net) vhost_net="yes"
>     ;;
> +  --disable-vhost-scsi) vhost_scsi="no"
> +  ;;
> +  --enable-vhost-scsi) vhost_scsi="yes"
> +  ;;
>     --disable-glx) glx="no"
>     ;;
>     --enable-glx) glx="yes"
> @@ -3553,6 +3559,7 @@ echo "sigev_thread_id   $sigev_thread_id"
>   echo "uuid support      $uuid"
>   echo "libcap-ng support $cap_ng"
>   echo "vhost-net support $vhost_net"
> +echo "vhost-scsi support $vhost_scsi"
>   echo "Trace backend     $trace_backend"
>   echo "Trace output file $trace_file-<pid>"
>   echo "spice support     $spice ($spice_protocol_version/$spice_server_version)"
> @@ -3836,6 +3843,9 @@ fi
>   if test "$virtfs" = "yes" ; then
>     echo "CONFIG_VIRTFS=y" >> $config_host_mak
>   fi
> +if test "$vhost_scsi" = "yes" ; then
> +  echo "CONFIG_VHOST_SCSI=y" >> $config_host_mak
> +fi
>   if test "$blobs" = "yes" ; then
>     echo "INSTALL_BLOBS=yes" >> $config_host_mak
>   fi
> diff --git a/hw/scsi/Makefile.objs b/hw/scsi/Makefile.objs
> index eaec6c8..121ddc5 100644
> --- a/hw/scsi/Makefile.objs
> +++ b/hw/scsi/Makefile.objs
> @@ -6,4 +6,8 @@ common-obj-$(CONFIG_VMW_PVSCSI_SCSI_PCI) += vmw_pvscsi.o
>   common-obj-$(CONFIG_ESP) += esp.o
>   common-obj-$(CONFIG_ESP_PCI) += esp-pci.o
>   obj-$(CONFIG_PSERIES) += spapr_vscsi.o
> -obj-$(CONFIG_VIRTIO) += virtio-scsi.o
> +
> +ifeq ($(CONFIG_VIRTIO),y)
> +obj-y += virtio-scsi.o
> +obj-$(CONFIG_VHOST_SCSI) += vhost-scsi.o
> +endif
> diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
> new file mode 100644
> index 0000000..3dd1a0f
> --- /dev/null
> +++ b/hw/scsi/vhost-scsi.c
> @@ -0,0 +1,288 @@
> +/*
> + * vhost_scsi host device
> + *
> + * Copyright IBM, Corp. 2011
> + *
> + * Authors:
> + *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
> + *
> + * Changes for QEMU mainline + tcm_vhost kernel upstream:
> + *  Nicholas Bellinger <nab@risingtidesystems.com>
> + *
> + * This work is licensed under the terms of the GNU LGPL, version 2 or later.
> + * See the COPYING.LIB file in the top-level directory.
> + *
> + */
> +
> +#include <sys/ioctl.h>
> +#include "config.h"
> +#include "qemu/queue.h"
> +#include "monitor/monitor.h"
> +#include "migration/migration.h"
> +#include "hw/virtio/vhost-scsi.h"
> +#include "hw/virtio/vhost.h"
> +#include "hw/virtio/virtio-scsi.h"
> +
> +static int vhost_scsi_set_endpoint(VHostSCSI *s)
> +{
> +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
> +    struct vhost_scsi_target backend;
> +    int ret;
> +
> +    memset(&backend, 0, sizeof(backend));
> +    pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
> +    ret = ioctl(s->dev.control, VHOST_SCSI_SET_ENDPOINT, &backend);
> +    if (ret < 0) {
> +        return -errno;
> +    }
> +    return 0;
> +}
> +
> +static void vhost_scsi_clear_endpoint(VHostSCSI *s)
> +{
> +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
> +    struct vhost_scsi_target backend;
> +
> +    memset(&backend, 0, sizeof(backend));
> +    pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn);
> +    ioctl(s->dev.control, VHOST_SCSI_CLEAR_ENDPOINT, &backend);
> +}
> +
> +static int vhost_scsi_start(VHostSCSI *s)
> +{
> +    int ret, abi_version, i;
> +    VirtIODevice *vdev = VIRTIO_DEVICE(s);
> +
> +    if (!vdev->binding->set_guest_notifiers) {
> +        error_report("binding does not support guest notifiers");
> +        return -ENOSYS;
> +    }
> +
> +    ret = ioctl(s->dev.control, VHOST_SCSI_GET_ABI_VERSION, &abi_version);
> +    if (ret < 0) {
> +        return -errno;
> +    }
> +    if (abi_version > VHOST_SCSI_ABI_VERSION) {
> +        error_report("vhost-scsi: The running tcm_vhost kernel abi_version:"
> +                     " %d is greater than vhost_scsi userspace supports: %d, please"
> +                     " upgrade your version of QEMU\n", abi_version,
> +                     VHOST_SCSI_ABI_VERSION);
> +        return -ENOSYS;
> +    }
> +
> +    ret = vhost_dev_enable_notifiers(&s->dev, vdev);
> +    if (ret < 0) {
> +        return ret;
> +    }
> +
> +    s->dev.acked_features = vdev->guest_features;
> +    ret = vhost_dev_start(&s->dev, vdev);
> +    if (ret < 0) {
> +        error_report("Error start vhost dev");
> +        goto err_notifiers;
> +    }
> +
> +    ret = vhost_scsi_set_endpoint(s);
> +    if (ret < 0) {
> +        error_report("Error set vhost-scsi endpoint");
> +        goto err_vhost_stop;
> +    }
> +
> +    ret = vdev->binding->set_guest_notifiers(vdev->binding_opaque, s->dev.nvqs, true);
> +    if (ret < 0) {
> +        error_report("Error binding guest notifier");
> +        goto err_endpoint;
> +    }
> +
> +    /* guest_notifier_mask/pending not used yet, so just unmask
> +     * everything here.  virtio-pci will do the right thing by
> +     * enabling/disabling irqfd.
> +     */
> +    for (i = 0; i < s->dev.nvqs; i++) {
> +        vhost_virtqueue_mask(&s->dev, vdev, i, false);
> +    }
> +
> +    return ret;
> +
> +err_endpoint:
> +    vhost_scsi_clear_endpoint(s);
> +err_vhost_stop:
> +    vhost_dev_stop(&s->dev, vdev);
> +err_notifiers:
> +    vhost_dev_disable_notifiers(&s->dev, vdev);
> +    return ret;
> +}
> +
> +static void vhost_scsi_stop(VHostSCSI *s)
> +{
> +    VirtIODevice *vdev = VIRTIO_DEVICE(s);
> +    int ret = 0;
> +
> +    if (!vdev->binding->set_guest_notifiers) {
> +        ret = vdev->binding->set_guest_notifiers(vdev->binding_opaque,
> +                                                 s->dev.nvqs, false);
> +        if (ret < 0) {
> +                error_report("vhost guest notifier cleanup failed: %d\n", ret);
> +        }
> +    }
> +    assert(ret >= 0);
> +
> +    vhost_scsi_clear_endpoint(s);
> +    vhost_dev_stop(&s->dev, vdev);
> +    vhost_dev_disable_notifiers(&s->dev, vdev);
> +}
> +
> +static uint32_t vhost_scsi_get_features(VirtIODevice *vdev,
> +                                        uint32_t features)
> +{
> +    VHostSCSI *s = VHOST_SCSI(vdev);
> +
> +    /* Clear features not supported by host kernel. */
> +    if (!(s->dev.features & (1 << VIRTIO_F_NOTIFY_ON_EMPTY))) {
> +        features &= ~(1 << VIRTIO_F_NOTIFY_ON_EMPTY);
> +    }
> +    if (!(s->dev.features & (1 << VIRTIO_RING_F_INDIRECT_DESC))) {
> +        features &= ~(1 << VIRTIO_RING_F_INDIRECT_DESC);
> +    }
> +    if (!(s->dev.features & (1 << VIRTIO_RING_F_EVENT_IDX))) {
> +        features &= ~(1 << VIRTIO_RING_F_EVENT_IDX);
> +    }
> +    if (!(s->dev.features & (1 << VIRTIO_SCSI_F_HOTPLUG))) {
> +        features &= ~(1 << VIRTIO_SCSI_F_HOTPLUG);
> +    }
> +
> +    return features;
> +}
> +
> +static void vhost_scsi_set_config(VirtIODevice *vdev,
> +                                  const uint8_t *config)
> +{
> +    VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
> +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
> +
> +    if ((uint32_t) ldl_raw(&scsiconf->sense_size) != vs->sense_size ||
> +        (uint32_t) ldl_raw(&scsiconf->cdb_size) != vs->cdb_size) {
> +        error_report("vhost-scsi does not support changing the sense data and CDB sizes");
> +        exit(1);
> +    }
> +}
> +
> +static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val)
> +{
> +    VHostSCSI *s = (VHostSCSI *)vdev;
> +    bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK);
> +
> +    if (s->dev.started == start) {
> +        return;
> +    }
> +
> +    if (start) {
> +        int ret;
> +
> +        ret = vhost_scsi_start(s);
> +        if (ret < 0) {
> +            error_report("virtio-scsi: unable to start vhost: %s\n",
> +                         strerror(-ret));
> +
> +            /* There is no userspace virtio-scsi fallback so exit */
> +            exit(1);
> +        }
> +    } else {
> +        vhost_scsi_stop(s);
> +    }
> +}
> +
> +static int vhost_scsi_init(VirtIODevice *vdev)
> +{
> +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
> +    VHostSCSI *s = VHOST_SCSI(vdev);
> +    int vhostfd = -1;
> +    int ret;
> +
> +    if (!vs->conf.wwpn) {
> +        error_report("vhost-scsi: missing wwpn\n");
> +        return -EINVAL;
> +    }
> +
> +    if (vs->conf.vhostfd) {
> +        vhostfd = monitor_handle_fd_param(cur_mon, vs->conf.vhostfd);
> +        if (vhostfd == -1) {
> +            error_report("vhost-scsi: unable to parse vhostfd\n");
> +            return -EINVAL;
> +        }
> +    }
> +
> +    ret = virtio_scsi_common_init(vs);
> +    if (ret < 0) {
> +        return ret;
> +    }
> +
> +    vdev->get_features = vhost_scsi_get_features;
> +    vdev->set_config = vhost_scsi_set_config;
> +    vdev->set_status = vhost_scsi_set_status;
> +
> +    s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
> +    s->dev.vqs = g_new(struct vhost_virtqueue, s->dev.nvqs);
> +    s->dev.vq_index = 0;
> +
> +    ret = vhost_dev_init(&s->dev, vhostfd, "/dev/vhost-scsi", true);
> +    if (ret < 0) {
> +        error_report("vhost-scsi: vhost initialization failed: %s\n",
> +                strerror(-ret));
> +        return ret;
> +    }
> +    s->dev.backend_features = 0;
> +
> +    error_setg(&s->migration_blocker,
> +            "vhost-scsi does not support migration");
> +    migrate_add_blocker(s->migration_blocker);
> +
> +    return 0;
> +}
> +
> +static int vhost_scsi_exit(DeviceState *qdev)
> +{
> +    VirtIODevice *vdev = VIRTIO_DEVICE(qdev);
> +    VHostSCSI *s = VHOST_SCSI(qdev);
> +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(qdev);
> +
> +    migrate_del_blocker(s->migration_blocker);
> +    error_free(s->migration_blocker);
> +
> +    /* This will stop vhost backend. */
> +    vhost_scsi_set_status(vdev, 0);
> +
> +    g_free(s->dev.vqs);
> +    return virtio_scsi_common_exit(vs);
> +}
> +
> +static Property vhost_scsi_properties[] = {
> +    DEFINE_VHOST_SCSI_PROPERTIES(VHostSCSI, parent_obj.conf),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void vhost_scsi_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
> +    dc->exit = vhost_scsi_exit;
> +    dc->props = vhost_scsi_properties;
> +    vdc->init = vhost_scsi_init;
> +    vdc->get_features = vhost_scsi_get_features;
> +    vdc->set_config = vhost_scsi_set_config;
> +    vdc->set_status = vhost_scsi_set_status;
> +}
> +
> +static const TypeInfo vhost_scsi_info = {
> +    .name = TYPE_VHOST_SCSI,
> +    .parent = TYPE_VIRTIO_SCSI_COMMON,
> +    .instance_size = sizeof(VHostSCSI),
> +    .class_init = vhost_scsi_class_init,
> +};
> +
> +static void virtio_register_types(void)
> +{
> +    type_register_static(&vhost_scsi_info);
> +}
> +
> +type_init(virtio_register_types)
> diff --git a/include/hw/virtio/vhost-scsi.h b/include/hw/virtio/vhost-scsi.h
> new file mode 100644
> index 0000000..85cc031
> --- /dev/null
> +++ b/include/hw/virtio/vhost-scsi.h
> @@ -0,0 +1,73 @@
> +/*
> + * vhost_scsi host device
> + *
> + * Copyright IBM, Corp. 2011
> + *
> + * Authors:
> + *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
> + *
> + * This work is licensed under the terms of the GNU LGPL, version 2 or later.
> + * See the COPYING.LIB file in the top-level directory.
> + *
> + */
> +
> +#ifndef VHOST_SCSI_H
> +#define VHOST_SCSI_H
> +
> +#include "qemu-common.h"
> +#include "hw/qdev.h"
> +#include "hw/virtio/virtio-scsi.h"
> +#include "hw/virtio/vhost.h"
> +
> +/*
> + * Used by QEMU userspace to ensure a consistent vhost-scsi ABI.
> + *
> + * ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate +
> + *            RFC-v2 vhost-scsi userspace.  Add GET_ABI_VERSION ioctl usage
> + * ABI Rev 1: January 2013. Ignore vhost_tpgt filed in struct vhost_scsi_target.
> + * 	      All the targets under vhost_wwpn can be seen and used by guest.
> + */
> +
> +#define VHOST_SCSI_ABI_VERSION 1
> +
> +/* TODO #include <linux/vhost.h> properly */
> +/* For VHOST_SCSI_SET_ENDPOINT/VHOST_SCSI_CLEAR_ENDPOINT ioctl */
> +struct vhost_scsi_target {
> +    int abi_version;
> +    char vhost_wwpn[224];
> +    unsigned short vhost_tpgt;
> +    unsigned short reserved;
> +};
> +
> +enum vhost_scsi_vq_list {
> +    VHOST_SCSI_VQ_CONTROL = 0,
> +    VHOST_SCSI_VQ_EVENT = 1,
> +    VHOST_SCSI_VQ_NUM_FIXED = 2,
> +};
> +
> +#define VHOST_VIRTIO 0xAF
> +#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
> +#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
> +#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
> +
> +#define TYPE_VHOST_SCSI "vhost-scsi"
> +#define VHOST_SCSI(obj) \
> +        OBJECT_CHECK(VHostSCSI, (obj), TYPE_VHOST_SCSI)
> +
> +typedef struct VHostSCSI {
> +    VirtIOSCSICommon parent_obj;
> +
> +    Error *migration_blocker;
> +
> +    struct vhost_dev dev;
> +} VHostSCSI;
> +
> +#define DEFINE_VHOST_SCSI_PROPERTIES(_state, _conf_field) \
> +    DEFINE_PROP_STRING("vhostfd", _state, _conf_field.vhostfd), \
> +    DEFINE_PROP_STRING("wwpn", _state, _conf_field.wwpn), \
> +    DEFINE_PROP_UINT32("num_queues", _state, _conf_field.num_queues, 1), \
> +    DEFINE_PROP_UINT32("max_sectors", _state, _conf_field.max_sectors, 0xFFFF), \
> +    DEFINE_PROP_UINT32("cmd_per_lun", _state, _conf_field.cmd_per_lun, 128)
> +
> +
> +#endif
> diff --git a/include/hw/virtio/virtio-scsi.h b/include/hw/virtio/virtio-scsi.h
> index 4a961b9..4db346b 100644
> --- a/include/hw/virtio/virtio-scsi.h
> +++ b/include/hw/virtio/virtio-scsi.h
> @@ -151,6 +151,8 @@ struct VirtIOSCSIConf {
>       uint32_t num_queues;
>       uint32_t max_sectors;
>       uint32_t cmd_per_lun;
> +    char *vhostfd;
> +    char *wwpn;
>   };
> 
>   typedef struct VirtIOSCSICommon {
> 


-- 
Best Regards

Wenchao Xia