[v2,09/16] qemu: add vhost-user helpers

Message ID 0c6d743253400594ad567d4f255ff30a80c62c4e.1566576129.git.crobinso@redhat.com
State New
Headers show
Series
  • Add vhost-user-gpu support
Related show

Commit Message

Cole Robinson Aug. 23, 2019, 4:21 p.m.
From: Marc-André Lureau <marcandre.lureau@redhat.com>

Add qemuVhostUserFetchConfigs() to discover vhost-user helpers.

qemuVhostUserFillDomainGPU() will find the first matching GPU helper
with the required capabilities and set the associated
vhost_user_binary.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
---
 src/conf/device_conf.c                        |   1 +
 src/conf/device_conf.h                        |   1 +
 src/qemu/Makefile.inc.am                      |   2 +
 src/qemu/qemu_vhost_user.c                    | 394 ++++++++++++++++++
 src/qemu/qemu_vhost_user.h                    |  48 +++
 tests/Makefile.am                             |   9 +
 .../etc/qemu/vhost-user/40-gpu.json           |   1 +
 .../etc/qemu/vhost-user/50-gpu.json           |   0
 .../qemu/vhost-user/test-vhost-user-gpu       |  11 +
 .../usr/share/qemu/vhost-user/30-gpu.json     |   1 +
 .../usr/share/qemu/vhost-user/50-gpu.json     |   8 +
 .../usr/share/qemu/vhost-user/60-gpu.json     |   1 +
 tests/qemuvhostusertest.c                     | 132 ++++++
 13 files changed, 609 insertions(+)
 create mode 100644 src/qemu/qemu_vhost_user.c
 create mode 100644 src/qemu/qemu_vhost_user.h
 create mode 120000 tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json
 create mode 100644 tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json
 create mode 100755 tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu
 create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json
 create mode 100644 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json
 create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json
 create mode 100644 tests/qemuvhostusertest.c

Comments

Cole Robinson Aug. 26, 2019, 8:30 p.m. | #1
On 8/23/19 12:21 PM, Cole Robinson wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
> 
> Add qemuVhostUserFetchConfigs() to discover vhost-user helpers.
> 
> qemuVhostUserFillDomainGPU() will find the first matching GPU helper
> with the required capabilities and set the associated
> vhost_user_binary.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> Signed-off-by: Cole Robinson <crobinso@redhat.com>
> ---
>  src/conf/device_conf.c                        |   1 +
>  src/conf/device_conf.h                        |   1 +
>  src/qemu/Makefile.inc.am                      |   2 +
>  src/qemu/qemu_vhost_user.c                    | 394 ++++++++++++++++++
>  src/qemu/qemu_vhost_user.h                    |  48 +++
>  tests/Makefile.am                             |   9 +
>  .../etc/qemu/vhost-user/40-gpu.json           |   1 +
>  .../etc/qemu/vhost-user/50-gpu.json           |   0
>  .../qemu/vhost-user/test-vhost-user-gpu       |  11 +
>  .../usr/share/qemu/vhost-user/30-gpu.json     |   1 +
>  .../usr/share/qemu/vhost-user/50-gpu.json     |   8 +
>  .../usr/share/qemu/vhost-user/60-gpu.json     |   1 +
>  tests/qemuvhostusertest.c                     | 132 ++++++
>  13 files changed, 609 insertions(+)
>  create mode 100644 src/qemu/qemu_vhost_user.c
>  create mode 100644 src/qemu/qemu_vhost_user.h
>  create mode 120000 tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json
>  create mode 100644 tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json
>  create mode 100755 tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu
>  create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json
>  create mode 100644 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json
>  create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json
>  create mode 100644 tests/qemuvhostusertest.c
> 
> diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c
> index 4c57f0995f..2f7077ddc4 100644
> --- a/src/conf/device_conf.c
> +++ b/src/conf/device_conf.c
> @@ -96,6 +96,7 @@ virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)
>      VIR_FREE(info->loadparm);
>      info->isolationGroup = 0;
>      info->isolationGroupLocked = false;
> +    VIR_FREE(info->vhost_user_binary);
>  }
>  
>  void
> diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h
> index d0854925e3..0b0c525ad8 100644
> --- a/src/conf/device_conf.h
> +++ b/src/conf/device_conf.h
> @@ -179,6 +179,7 @@ struct _virDomainDeviceInfo {
>       * cases we might want to prevent that from happening by
>       * locking the isolation group */
>      bool isolationGroupLocked;
> +    char *vhost_user_binary;
>  };
>  
>  void virDomainDeviceInfoClear(virDomainDeviceInfoPtr info);
> diff --git a/src/qemu/Makefile.inc.am b/src/qemu/Makefile.inc.am
> index f7a0fa4a84..18a9220d01 100644
> --- a/src/qemu/Makefile.inc.am
> +++ b/src/qemu/Makefile.inc.am
> @@ -60,6 +60,8 @@ QEMU_DRIVER_SOURCES = \
>  	qemu/qemu_qapi.h \
>  	qemu/qemu_tpm.c \
>  	qemu/qemu_tpm.h \
> +	qemu/qemu_vhost_user.c \
> +	qemu/qemu_vhost_user.h \
>  	$(NULL)
>  
>  
> diff --git a/src/qemu/qemu_vhost_user.c b/src/qemu/qemu_vhost_user.c
> new file mode 100644
> index 0000000000..7a97052ab9
> --- /dev/null
> +++ b/src/qemu/qemu_vhost_user.c
> @@ -0,0 +1,394 @@
> +/*
> + * qemu_vhost_user.c: QEMU vhost-user
> + *
> + * Copyright (C) 2019 Red Hat, Inc.
> + *
> + * This library is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * This library is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with this library.  If not, see
> + * <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <config.h>
> +
> +#include "qemu_vhost_user.h"
> +#include "qemu_configs.h"
> +#include "virjson.h"
> +#include "virlog.h"
> +#include "virstring.h"
> +#include "viralloc.h"
> +#include "virenum.h"
> +
> +#define VIR_FROM_THIS VIR_FROM_QEMU
> +
> +VIR_LOG_INIT("qemu.qemu_vhost_user");
> +
> +typedef enum {
> +    QEMU_VHOST_USER_TYPE_NONE = 0,
> +    QEMU_VHOST_USER_TYPE_9P,
> +    QEMU_VHOST_USER_TYPE_BALLOON,
> +    QEMU_VHOST_USER_TYPE_BLOCK,
> +    QEMU_VHOST_USER_TYPE_CAIF,
> +    QEMU_VHOST_USER_TYPE_CONSOLE,
> +    QEMU_VHOST_USER_TYPE_CRYPTO,
> +    QEMU_VHOST_USER_TYPE_GPU,
> +    QEMU_VHOST_USER_TYPE_INPUT,
> +    QEMU_VHOST_USER_TYPE_NET,
> +    QEMU_VHOST_USER_TYPE_RNG,
> +    QEMU_VHOST_USER_TYPE_RPMSG,
> +    QEMU_VHOST_USER_TYPE_RPROC_SERIAL,
> +    QEMU_VHOST_USER_TYPE_SCSI,
> +    QEMU_VHOST_USER_TYPE_VSOCK,
> +
> +    QEMU_VHOST_USER_TYPE_LAST
> +} qemuVhostUserType;
> +
> +VIR_ENUM_DECL(qemuVhostUserType);
> +VIR_ENUM_IMPL(qemuVhostUserType,
> +              QEMU_VHOST_USER_TYPE_LAST,
> +              "",
> +              "9p",
> +              "balloon",
> +              "block",
> +              "caif",
> +              "console",
> +              "crypto",
> +              "gpu",
> +              "input",
> +              "net",
> +              "rng",
> +              "rpmsg",
> +              "rproc-serial",
> +              "scsi",
> +              "vsock",
> +);
> +
> +typedef enum {
> +    QEMU_VHOST_USER_GPU_FEATURE_NONE = 0,
> +    QEMU_VHOST_USER_GPU_FEATURE_VIRGL,
> +    QEMU_VHOST_USER_GPU_FEATURE_RENDER_NODE,
> +
> +    QEMU_VHOST_USER_GPU_FEATURE_LAST
> +} qemuVhostUserGPUFeature;
> +
> +VIR_ENUM_DECL(qemuVhostUserGPUFeature);
> +VIR_ENUM_IMPL(qemuVhostUserGPUFeature,
> +              QEMU_VHOST_USER_GPU_FEATURE_LAST,
> +              "",
> +              "virgl",
> +              "render-node",
> +);
> +
> +typedef struct _qemuVhostUserGPU qemuVhostUserGPU;
> +typedef qemuVhostUserGPU *qemuVhostUserGPUPtr;
> +struct _qemuVhostUserGPU {
> +    size_t nfeatures;
> +    qemuVhostUserGPUFeature *features;
> +};
> +
> +struct _qemuVhostUser {
> +    /* Description intentionally not parsed. */
> +    qemuVhostUserType type;
> +    char *binary;
> +    /* Tags intentionally not parsed. */
> +
> +    union {
> +        qemuVhostUserGPU gpu;
> +    } capabilities;
> +};
> +
> +static void
> +qemuVhostUserGPUFeatureFree(qemuVhostUserGPUFeature *features)
> +{
> +    VIR_FREE(features);
> +}
> +
> +

Inconsistent double newline spacing here. But double newline seems to be
more common for new code so I suggest standardizing on that.

> +VIR_DEFINE_AUTOPTR_FUNC(qemuVhostUserGPUFeature, qemuVhostUserGPUFeatureFree);
> +
> +void
> +qemuVhostUserFree(qemuVhostUserPtr vu)
> +{
> +    if (!vu)
> +        return;
> +
> +    if (vu->type == QEMU_VHOST_USER_TYPE_GPU)
> +        VIR_FREE(vu->capabilities.gpu.features);
> +
> +    VIR_FREE(vu->binary);
> +
> +    VIR_FREE(vu);
> +}
> +
> +/* 1MiB should be enough for everybody (TM) */
> +#define DOCUMENT_SIZE (1024 * 1024)
> +

Since this is identical to qemu_firmware.c, maybe give it a proper name
and move it to the shared file?

Otherwise this and the preceding uncommented patches look okay to me,
the behavior here largely mirrors qemu_firmware.c

- Cole

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Ján Tomko Aug. 27, 2019, 8:29 a.m. | #2
On Fri, Aug 23, 2019 at 12:21:53PM -0400, Cole Robinson wrote:
>From: Marc-André Lureau <marcandre.lureau@redhat.com>

>

>Add qemuVhostUserFetchConfigs() to discover vhost-user helpers.

>

>qemuVhostUserFillDomainGPU() will find the first matching GPU helper

>with the required capabilities and set the associated

>vhost_user_binary.

>


Looks good, but it seems like something we might want to start caching
over time, especially if more than one helper per domain will be needed.

>Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

>Signed-off-by: Cole Robinson <crobinso@redhat.com>

>---

> src/conf/device_conf.c                        |   1 +

> src/conf/device_conf.h                        |   1 +

> src/qemu/Makefile.inc.am                      |   2 +

> src/qemu/qemu_vhost_user.c                    | 394 ++++++++++++++++++

> src/qemu/qemu_vhost_user.h                    |  48 +++

> tests/Makefile.am                             |   9 +

> .../etc/qemu/vhost-user/40-gpu.json           |   1 +

> .../etc/qemu/vhost-user/50-gpu.json           |   0

> .../qemu/vhost-user/test-vhost-user-gpu       |  11 +

> .../usr/share/qemu/vhost-user/30-gpu.json     |   1 +

> .../usr/share/qemu/vhost-user/50-gpu.json     |   8 +

> .../usr/share/qemu/vhost-user/60-gpu.json     |   1 +

> tests/qemuvhostusertest.c                     | 132 ++++++

> 13 files changed, 609 insertions(+)

> create mode 100644 src/qemu/qemu_vhost_user.c

> create mode 100644 src/qemu/qemu_vhost_user.h

> create mode 120000 tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json

> create mode 100644 tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json

> create mode 100755 tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu

> create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json

> create mode 100644 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json

> create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json

> create mode 100644 tests/qemuvhostusertest.c

>

>diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c

>index 4c57f0995f..2f7077ddc4 100644

>--- a/src/conf/device_conf.c

>+++ b/src/conf/device_conf.c

>@@ -96,6 +96,7 @@ virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)

>     VIR_FREE(info->loadparm);

>     info->isolationGroup = 0;

>     info->isolationGroupLocked = false;

>+    VIR_FREE(info->vhost_user_binary);

> }

>

> void

>diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h

>index d0854925e3..0b0c525ad8 100644

>--- a/src/conf/device_conf.h

>+++ b/src/conf/device_conf.h

>@@ -179,6 +179,7 @@ struct _virDomainDeviceInfo {

>      * cases we might want to prevent that from happening by

>      * locking the isolation group */

>     bool isolationGroupLocked;

>+    char *vhost_user_binary;

> };

>


Not sure about the placement in DeviceInfo, looks more fit for 'driver'
to me.

Jano
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Marc-André Lureau Aug. 30, 2019, 12:02 p.m. | #3
Hi

On Tue, Aug 27, 2019 at 12:30 AM Cole Robinson <crobinso@redhat.com> wrote:
>
> On 8/23/19 12:21 PM, Cole Robinson wrote:
> > From: Marc-André Lureau <marcandre.lureau@redhat.com>
> >
> > Add qemuVhostUserFetchConfigs() to discover vhost-user helpers.
> >
> > qemuVhostUserFillDomainGPU() will find the first matching GPU helper
> > with the required capabilities and set the associated
> > vhost_user_binary.
> >
> > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > Signed-off-by: Cole Robinson <crobinso@redhat.com>
> > ---
> >  src/conf/device_conf.c                        |   1 +
> >  src/conf/device_conf.h                        |   1 +
> >  src/qemu/Makefile.inc.am                      |   2 +
> >  src/qemu/qemu_vhost_user.c                    | 394 ++++++++++++++++++
> >  src/qemu/qemu_vhost_user.h                    |  48 +++
> >  tests/Makefile.am                             |   9 +
> >  .../etc/qemu/vhost-user/40-gpu.json           |   1 +
> >  .../etc/qemu/vhost-user/50-gpu.json           |   0
> >  .../qemu/vhost-user/test-vhost-user-gpu       |  11 +
> >  .../usr/share/qemu/vhost-user/30-gpu.json     |   1 +
> >  .../usr/share/qemu/vhost-user/50-gpu.json     |   8 +
> >  .../usr/share/qemu/vhost-user/60-gpu.json     |   1 +
> >  tests/qemuvhostusertest.c                     | 132 ++++++
> >  13 files changed, 609 insertions(+)
> >  create mode 100644 src/qemu/qemu_vhost_user.c
> >  create mode 100644 src/qemu/qemu_vhost_user.h
> >  create mode 120000 tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json
> >  create mode 100644 tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json
> >  create mode 100755 tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu
> >  create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json
> >  create mode 100644 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json
> >  create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json
> >  create mode 100644 tests/qemuvhostusertest.c
> >
> > diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c
> > index 4c57f0995f..2f7077ddc4 100644
> > --- a/src/conf/device_conf.c
> > +++ b/src/conf/device_conf.c
> > @@ -96,6 +96,7 @@ virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)
> >      VIR_FREE(info->loadparm);
> >      info->isolationGroup = 0;
> >      info->isolationGroupLocked = false;
> > +    VIR_FREE(info->vhost_user_binary);
> >  }
> >
> >  void
> > diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h
> > index d0854925e3..0b0c525ad8 100644
> > --- a/src/conf/device_conf.h
> > +++ b/src/conf/device_conf.h
> > @@ -179,6 +179,7 @@ struct _virDomainDeviceInfo {
> >       * cases we might want to prevent that from happening by
> >       * locking the isolation group */
> >      bool isolationGroupLocked;
> > +    char *vhost_user_binary;
> >  };
> >
> >  void virDomainDeviceInfoClear(virDomainDeviceInfoPtr info);
> > diff --git a/src/qemu/Makefile.inc.am b/src/qemu/Makefile.inc.am
> > index f7a0fa4a84..18a9220d01 100644
> > --- a/src/qemu/Makefile.inc.am
> > +++ b/src/qemu/Makefile.inc.am
> > @@ -60,6 +60,8 @@ QEMU_DRIVER_SOURCES = \
> >       qemu/qemu_qapi.h \
> >       qemu/qemu_tpm.c \
> >       qemu/qemu_tpm.h \
> > +     qemu/qemu_vhost_user.c \
> > +     qemu/qemu_vhost_user.h \
> >       $(NULL)
> >
> >
> > diff --git a/src/qemu/qemu_vhost_user.c b/src/qemu/qemu_vhost_user.c
> > new file mode 100644
> > index 0000000000..7a97052ab9
> > --- /dev/null
> > +++ b/src/qemu/qemu_vhost_user.c
> > @@ -0,0 +1,394 @@
> > +/*
> > + * qemu_vhost_user.c: QEMU vhost-user
> > + *
> > + * Copyright (C) 2019 Red Hat, Inc.
> > + *
> > + * This library is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU Lesser General Public
> > + * License as published by the Free Software Foundation; either
> > + * version 2.1 of the License, or (at your option) any later version.
> > + *
> > + * This library is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> > + * Lesser General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU Lesser General Public
> > + * License along with this library.  If not, see
> > + * <http://www.gnu.org/licenses/>.
> > + */
> > +
> > +#include <config.h>
> > +
> > +#include "qemu_vhost_user.h"
> > +#include "qemu_configs.h"
> > +#include "virjson.h"
> > +#include "virlog.h"
> > +#include "virstring.h"
> > +#include "viralloc.h"
> > +#include "virenum.h"
> > +
> > +#define VIR_FROM_THIS VIR_FROM_QEMU
> > +
> > +VIR_LOG_INIT("qemu.qemu_vhost_user");
> > +
> > +typedef enum {
> > +    QEMU_VHOST_USER_TYPE_NONE = 0,
> > +    QEMU_VHOST_USER_TYPE_9P,
> > +    QEMU_VHOST_USER_TYPE_BALLOON,
> > +    QEMU_VHOST_USER_TYPE_BLOCK,
> > +    QEMU_VHOST_USER_TYPE_CAIF,
> > +    QEMU_VHOST_USER_TYPE_CONSOLE,
> > +    QEMU_VHOST_USER_TYPE_CRYPTO,
> > +    QEMU_VHOST_USER_TYPE_GPU,
> > +    QEMU_VHOST_USER_TYPE_INPUT,
> > +    QEMU_VHOST_USER_TYPE_NET,
> > +    QEMU_VHOST_USER_TYPE_RNG,
> > +    QEMU_VHOST_USER_TYPE_RPMSG,
> > +    QEMU_VHOST_USER_TYPE_RPROC_SERIAL,
> > +    QEMU_VHOST_USER_TYPE_SCSI,
> > +    QEMU_VHOST_USER_TYPE_VSOCK,
> > +
> > +    QEMU_VHOST_USER_TYPE_LAST
> > +} qemuVhostUserType;
> > +
> > +VIR_ENUM_DECL(qemuVhostUserType);
> > +VIR_ENUM_IMPL(qemuVhostUserType,
> > +              QEMU_VHOST_USER_TYPE_LAST,
> > +              "",
> > +              "9p",
> > +              "balloon",
> > +              "block",
> > +              "caif",
> > +              "console",
> > +              "crypto",
> > +              "gpu",
> > +              "input",
> > +              "net",
> > +              "rng",
> > +              "rpmsg",
> > +              "rproc-serial",
> > +              "scsi",
> > +              "vsock",
> > +);
> > +
> > +typedef enum {
> > +    QEMU_VHOST_USER_GPU_FEATURE_NONE = 0,
> > +    QEMU_VHOST_USER_GPU_FEATURE_VIRGL,
> > +    QEMU_VHOST_USER_GPU_FEATURE_RENDER_NODE,
> > +
> > +    QEMU_VHOST_USER_GPU_FEATURE_LAST
> > +} qemuVhostUserGPUFeature;
> > +
> > +VIR_ENUM_DECL(qemuVhostUserGPUFeature);
> > +VIR_ENUM_IMPL(qemuVhostUserGPUFeature,
> > +              QEMU_VHOST_USER_GPU_FEATURE_LAST,
> > +              "",
> > +              "virgl",
> > +              "render-node",
> > +);
> > +
> > +typedef struct _qemuVhostUserGPU qemuVhostUserGPU;
> > +typedef qemuVhostUserGPU *qemuVhostUserGPUPtr;
> > +struct _qemuVhostUserGPU {
> > +    size_t nfeatures;
> > +    qemuVhostUserGPUFeature *features;
> > +};
> > +
> > +struct _qemuVhostUser {
> > +    /* Description intentionally not parsed. */
> > +    qemuVhostUserType type;
> > +    char *binary;
> > +    /* Tags intentionally not parsed. */
> > +
> > +    union {
> > +        qemuVhostUserGPU gpu;
> > +    } capabilities;
> > +};
> > +
> > +static void
> > +qemuVhostUserGPUFeatureFree(qemuVhostUserGPUFeature *features)
> > +{
> > +    VIR_FREE(features);
> > +}
> > +
> > +
>
> Inconsistent double newline spacing here. But double newline seems to be
> more common for new code so I suggest standardizing on that.

ok

>
> > +VIR_DEFINE_AUTOPTR_FUNC(qemuVhostUserGPUFeature, qemuVhostUserGPUFeatureFree);
> > +
> > +void
> > +qemuVhostUserFree(qemuVhostUserPtr vu)
> > +{
> > +    if (!vu)
> > +        return;
> > +
> > +    if (vu->type == QEMU_VHOST_USER_TYPE_GPU)
> > +        VIR_FREE(vu->capabilities.gpu.features);
> > +
> > +    VIR_FREE(vu->binary);
> > +
> > +    VIR_FREE(vu);
> > +}
> > +
> > +/* 1MiB should be enough for everybody (TM) */
> > +#define DOCUMENT_SIZE (1024 * 1024)
> > +
>
> Since this is identical to qemu_firmware.c, maybe give it a proper name
> and move it to the shared file?

QEMU_INTEROP_DOCUMENT_SIZE ? (not sure it's really worth it, I am not
changing it yet)

>
> Otherwise this and the preceding uncommented patches look okay to me,
> the behavior here largely mirrors qemu_firmware.c

thanks

>
> - Cole
>
> --
> libvir-list mailing list
> libvir-list@redhat.com
> https://www.redhat.com/mailman/listinfo/libvir-list
Marc-André Lureau Aug. 30, 2019, 12:04 p.m. | #4
Hi

On Tue, Aug 27, 2019 at 12:29 PM Ján Tomko <jtomko@redhat.com> wrote:
>
> On Fri, Aug 23, 2019 at 12:21:53PM -0400, Cole Robinson wrote:
> >From: Marc-André Lureau <marcandre.lureau@redhat.com>
> >
> >Add qemuVhostUserFetchConfigs() to discover vhost-user helpers.
> >
> >qemuVhostUserFillDomainGPU() will find the first matching GPU helper
> >with the required capabilities and set the associated
> >vhost_user_binary.
> >
>
> Looks good, but it seems like something we might want to start caching
> over time, especially if more than one helper per domain will be needed.
>
> >Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> >Signed-off-by: Cole Robinson <crobinso@redhat.com>
> >---
> > src/conf/device_conf.c                        |   1 +
> > src/conf/device_conf.h                        |   1 +
> > src/qemu/Makefile.inc.am                      |   2 +
> > src/qemu/qemu_vhost_user.c                    | 394 ++++++++++++++++++
> > src/qemu/qemu_vhost_user.h                    |  48 +++
> > tests/Makefile.am                             |   9 +
> > .../etc/qemu/vhost-user/40-gpu.json           |   1 +
> > .../etc/qemu/vhost-user/50-gpu.json           |   0
> > .../qemu/vhost-user/test-vhost-user-gpu       |  11 +
> > .../usr/share/qemu/vhost-user/30-gpu.json     |   1 +
> > .../usr/share/qemu/vhost-user/50-gpu.json     |   8 +
> > .../usr/share/qemu/vhost-user/60-gpu.json     |   1 +
> > tests/qemuvhostusertest.c                     | 132 ++++++
> > 13 files changed, 609 insertions(+)
> > create mode 100644 src/qemu/qemu_vhost_user.c
> > create mode 100644 src/qemu/qemu_vhost_user.h
> > create mode 120000 tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json
> > create mode 100644 tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json
> > create mode 100755 tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu
> > create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json
> > create mode 100644 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json
> > create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json
> > create mode 100644 tests/qemuvhostusertest.c
> >
> >diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c
> >index 4c57f0995f..2f7077ddc4 100644
> >--- a/src/conf/device_conf.c
> >+++ b/src/conf/device_conf.c
> >@@ -96,6 +96,7 @@ virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)
> >     VIR_FREE(info->loadparm);
> >     info->isolationGroup = 0;
> >     info->isolationGroupLocked = false;
> >+    VIR_FREE(info->vhost_user_binary);
> > }
> >
> > void
> >diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h
> >index d0854925e3..0b0c525ad8 100644
> >--- a/src/conf/device_conf.h
> >+++ b/src/conf/device_conf.h
> >@@ -179,6 +179,7 @@ struct _virDomainDeviceInfo {
> >      * cases we might want to prevent that from happening by
> >      * locking the isolation group */
> >     bool isolationGroupLocked;
> >+    char *vhost_user_binary;
> > };
> >
>
> Not sure about the placement in DeviceInfo, looks more fit for 'driver'
> to me.
>

That wouldn't follow firmware code, but other than that, driver
doesn't really fit either since it's a per-domain/device value.
Ján Tomko Aug. 30, 2019, 12:24 p.m. | #5
On Fri, Aug 30, 2019 at 04:04:14PM +0400, Marc-André Lureau wrote:
>Hi

>

>On Tue, Aug 27, 2019 at 12:29 PM Ján Tomko <jtomko@redhat.com> wrote:

>>

>> On Fri, Aug 23, 2019 at 12:21:53PM -0400, Cole Robinson wrote:

>> >From: Marc-André Lureau <marcandre.lureau@redhat.com>

>> >

>> >Add qemuVhostUserFetchConfigs() to discover vhost-user helpers.

>> >

>> >qemuVhostUserFillDomainGPU() will find the first matching GPU helper

>> >with the required capabilities and set the associated

>> >vhost_user_binary.

>> >

>>

>> Looks good, but it seems like something we might want to start caching

>> over time, especially if more than one helper per domain will be needed.

>>

>> >Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

>> >Signed-off-by: Cole Robinson <crobinso@redhat.com>

>> >---

>> > src/conf/device_conf.c                        |   1 +

>> > src/conf/device_conf.h                        |   1 +

>> > src/qemu/Makefile.inc.am                      |   2 +

>> > src/qemu/qemu_vhost_user.c                    | 394 ++++++++++++++++++

>> > src/qemu/qemu_vhost_user.h                    |  48 +++

>> > tests/Makefile.am                             |   9 +

>> > .../etc/qemu/vhost-user/40-gpu.json           |   1 +

>> > .../etc/qemu/vhost-user/50-gpu.json           |   0

>> > .../qemu/vhost-user/test-vhost-user-gpu       |  11 +

>> > .../usr/share/qemu/vhost-user/30-gpu.json     |   1 +

>> > .../usr/share/qemu/vhost-user/50-gpu.json     |   8 +

>> > .../usr/share/qemu/vhost-user/60-gpu.json     |   1 +

>> > tests/qemuvhostusertest.c                     | 132 ++++++

>> > 13 files changed, 609 insertions(+)

>> > create mode 100644 src/qemu/qemu_vhost_user.c

>> > create mode 100644 src/qemu/qemu_vhost_user.h

>> > create mode 120000 tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json

>> > create mode 100644 tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json

>> > create mode 100755 tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu

>> > create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json

>> > create mode 100644 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json

>> > create mode 120000 tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json

>> > create mode 100644 tests/qemuvhostusertest.c

>> >

>> >diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c

>> >index 4c57f0995f..2f7077ddc4 100644

>> >--- a/src/conf/device_conf.c

>> >+++ b/src/conf/device_conf.c

>> >@@ -96,6 +96,7 @@ virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)

>> >     VIR_FREE(info->loadparm);

>> >     info->isolationGroup = 0;

>> >     info->isolationGroupLocked = false;

>> >+    VIR_FREE(info->vhost_user_binary);

>> > }

>> >

>> > void

>> >diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h

>> >index d0854925e3..0b0c525ad8 100644

>> >--- a/src/conf/device_conf.h

>> >+++ b/src/conf/device_conf.h

>> >@@ -179,6 +179,7 @@ struct _virDomainDeviceInfo {

>> >      * cases we might want to prevent that from happening by

>> >      * locking the isolation group */

>> >     bool isolationGroupLocked;

>> >+    char *vhost_user_binary;

>> > };

>> >

>>

>> Not sure about the placement in DeviceInfo, looks more fit for 'driver'

>> to me.

>>

>

>That wouldn't follow firmware code, but other than that, driver

>doesn't really fit either since it's a per-domain/device value.

>


virDomainVideoDriverDefPtr driver;
is the one I meant.

Jano
--
libvir-list mailing list
libvir-list@redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list

Patch

diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c
index 4c57f0995f..2f7077ddc4 100644
--- a/src/conf/device_conf.c
+++ b/src/conf/device_conf.c
@@ -96,6 +96,7 @@  virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)
     VIR_FREE(info->loadparm);
     info->isolationGroup = 0;
     info->isolationGroupLocked = false;
+    VIR_FREE(info->vhost_user_binary);
 }
 
 void
diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h
index d0854925e3..0b0c525ad8 100644
--- a/src/conf/device_conf.h
+++ b/src/conf/device_conf.h
@@ -179,6 +179,7 @@  struct _virDomainDeviceInfo {
      * cases we might want to prevent that from happening by
      * locking the isolation group */
     bool isolationGroupLocked;
+    char *vhost_user_binary;
 };
 
 void virDomainDeviceInfoClear(virDomainDeviceInfoPtr info);
diff --git a/src/qemu/Makefile.inc.am b/src/qemu/Makefile.inc.am
index f7a0fa4a84..18a9220d01 100644
--- a/src/qemu/Makefile.inc.am
+++ b/src/qemu/Makefile.inc.am
@@ -60,6 +60,8 @@  QEMU_DRIVER_SOURCES = \
 	qemu/qemu_qapi.h \
 	qemu/qemu_tpm.c \
 	qemu/qemu_tpm.h \
+	qemu/qemu_vhost_user.c \
+	qemu/qemu_vhost_user.h \
 	$(NULL)
 
 
diff --git a/src/qemu/qemu_vhost_user.c b/src/qemu/qemu_vhost_user.c
new file mode 100644
index 0000000000..7a97052ab9
--- /dev/null
+++ b/src/qemu/qemu_vhost_user.c
@@ -0,0 +1,394 @@ 
+/*
+ * qemu_vhost_user.c: QEMU vhost-user
+ *
+ * Copyright (C) 2019 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#include "qemu_vhost_user.h"
+#include "qemu_configs.h"
+#include "virjson.h"
+#include "virlog.h"
+#include "virstring.h"
+#include "viralloc.h"
+#include "virenum.h"
+
+#define VIR_FROM_THIS VIR_FROM_QEMU
+
+VIR_LOG_INIT("qemu.qemu_vhost_user");
+
+typedef enum {
+    QEMU_VHOST_USER_TYPE_NONE = 0,
+    QEMU_VHOST_USER_TYPE_9P,
+    QEMU_VHOST_USER_TYPE_BALLOON,
+    QEMU_VHOST_USER_TYPE_BLOCK,
+    QEMU_VHOST_USER_TYPE_CAIF,
+    QEMU_VHOST_USER_TYPE_CONSOLE,
+    QEMU_VHOST_USER_TYPE_CRYPTO,
+    QEMU_VHOST_USER_TYPE_GPU,
+    QEMU_VHOST_USER_TYPE_INPUT,
+    QEMU_VHOST_USER_TYPE_NET,
+    QEMU_VHOST_USER_TYPE_RNG,
+    QEMU_VHOST_USER_TYPE_RPMSG,
+    QEMU_VHOST_USER_TYPE_RPROC_SERIAL,
+    QEMU_VHOST_USER_TYPE_SCSI,
+    QEMU_VHOST_USER_TYPE_VSOCK,
+
+    QEMU_VHOST_USER_TYPE_LAST
+} qemuVhostUserType;
+
+VIR_ENUM_DECL(qemuVhostUserType);
+VIR_ENUM_IMPL(qemuVhostUserType,
+              QEMU_VHOST_USER_TYPE_LAST,
+              "",
+              "9p",
+              "balloon",
+              "block",
+              "caif",
+              "console",
+              "crypto",
+              "gpu",
+              "input",
+              "net",
+              "rng",
+              "rpmsg",
+              "rproc-serial",
+              "scsi",
+              "vsock",
+);
+
+typedef enum {
+    QEMU_VHOST_USER_GPU_FEATURE_NONE = 0,
+    QEMU_VHOST_USER_GPU_FEATURE_VIRGL,
+    QEMU_VHOST_USER_GPU_FEATURE_RENDER_NODE,
+
+    QEMU_VHOST_USER_GPU_FEATURE_LAST
+} qemuVhostUserGPUFeature;
+
+VIR_ENUM_DECL(qemuVhostUserGPUFeature);
+VIR_ENUM_IMPL(qemuVhostUserGPUFeature,
+              QEMU_VHOST_USER_GPU_FEATURE_LAST,
+              "",
+              "virgl",
+              "render-node",
+);
+
+typedef struct _qemuVhostUserGPU qemuVhostUserGPU;
+typedef qemuVhostUserGPU *qemuVhostUserGPUPtr;
+struct _qemuVhostUserGPU {
+    size_t nfeatures;
+    qemuVhostUserGPUFeature *features;
+};
+
+struct _qemuVhostUser {
+    /* Description intentionally not parsed. */
+    qemuVhostUserType type;
+    char *binary;
+    /* Tags intentionally not parsed. */
+
+    union {
+        qemuVhostUserGPU gpu;
+    } capabilities;
+};
+
+static void
+qemuVhostUserGPUFeatureFree(qemuVhostUserGPUFeature *features)
+{
+    VIR_FREE(features);
+}
+
+
+VIR_DEFINE_AUTOPTR_FUNC(qemuVhostUserGPUFeature, qemuVhostUserGPUFeatureFree);
+
+void
+qemuVhostUserFree(qemuVhostUserPtr vu)
+{
+    if (!vu)
+        return;
+
+    if (vu->type == QEMU_VHOST_USER_TYPE_GPU)
+        VIR_FREE(vu->capabilities.gpu.features);
+
+    VIR_FREE(vu->binary);
+
+    VIR_FREE(vu);
+}
+
+/* 1MiB should be enough for everybody (TM) */
+#define DOCUMENT_SIZE (1024 * 1024)
+
+static int
+qemuVhostUserTypeParse(const char *path,
+                       virJSONValuePtr doc,
+                       qemuVhostUserPtr vu)
+{
+    const char *type = virJSONValueObjectGetString(doc, "type");
+    int tmp;
+
+    VIR_DEBUG("vhost-user description path '%s' type : %s",
+              path, type);
+
+    if ((tmp = qemuVhostUserTypeTypeFromString(type)) <= 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("unknown vhost-user type: '%s'"),
+                       type);
+        return -1;
+    }
+
+    vu->type = tmp;
+
+    return 0;
+}
+
+static int
+qemuVhostUserBinaryParse(const char *path,
+                         virJSONValuePtr doc,
+                         qemuVhostUserPtr vu)
+{
+    const char *binary = virJSONValueObjectGetString(doc, "binary");
+
+    VIR_DEBUG("vhost-user description path '%s' binary : %s",
+              path, binary);
+
+    if (VIR_STRDUP(vu->binary, binary) < 0)
+        return -1;
+
+    return 0;
+}
+
+qemuVhostUserPtr
+qemuVhostUserParse(const char *path)
+{
+    VIR_AUTOFREE(char *) cont = NULL;
+    VIR_AUTOPTR(virJSONValue) doc = NULL;
+    VIR_AUTOPTR(qemuVhostUser) vu = NULL;
+    qemuVhostUserPtr ret = NULL;
+
+    if (virFileReadAll(path, DOCUMENT_SIZE, &cont) < 0)
+        return NULL;
+
+    if (!(doc = virJSONValueFromString(cont))) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("unable to parse json file '%s'"),
+                       path);
+        return NULL;
+    }
+
+    if (VIR_ALLOC(vu) < 0)
+        return NULL;
+
+    if (qemuVhostUserTypeParse(path, doc, vu) < 0)
+        return NULL;
+
+    if (qemuVhostUserBinaryParse(path, doc, vu) < 0)
+        return NULL;
+
+    VIR_STEAL_PTR(ret, vu);
+    return ret;
+}
+
+char *
+qemuVhostUserFormat(qemuVhostUserPtr vu)
+{
+    VIR_AUTOPTR(virJSONValue) doc = NULL;
+
+    if (!vu)
+        return NULL;
+
+    if (!(doc = virJSONValueNewObject()))
+        return NULL;
+
+    if (virJSONValueObjectAppendString(doc, "type",
+                                       qemuVhostUserTypeTypeToString(vu->type)) < 0)
+        return NULL;
+
+    if (virJSONValueObjectAppendString(doc, "binary", vu->binary) < 0)
+        return NULL;
+
+    return virJSONValueToString(doc, true);
+}
+
+int
+qemuVhostUserFetchConfigs(char ***configs,
+                          bool privileged)
+{
+    return qemuFetchConfigs("vhost-user", configs, privileged);
+}
+
+static ssize_t
+qemuVhostUserFetchParsedConfigs(bool privileged,
+                                qemuVhostUserPtr **vhostuserRet,
+                                char ***pathsRet)
+{
+    VIR_AUTOSTRINGLIST paths = NULL;
+    size_t npaths;
+    qemuVhostUserPtr *vus = NULL;
+    size_t i;
+
+    if (qemuVhostUserFetchConfigs(&paths, privileged) < 0)
+        return -1;
+
+    npaths = virStringListLength((const char **)paths);
+
+    if (VIR_ALLOC_N(vus, npaths) < 0)
+        return -1;
+
+    for (i = 0; i < npaths; i++) {
+        if (!(vus[i] = qemuVhostUserParse(paths[i])))
+            goto error;
+    }
+
+    VIR_STEAL_PTR(*vhostuserRet, vus);
+    if (pathsRet)
+        VIR_STEAL_PTR(*pathsRet, paths);
+    return npaths;
+
+ error:
+    while (i > 0)
+        qemuVhostUserFree(vus[--i]);
+    VIR_FREE(vus);
+    return -1;
+}
+
+
+static int
+qemuVhostUserGPUFillCapabilities(qemuVhostUserPtr vu,
+                                 virJSONValuePtr doc)
+{
+    qemuVhostUserGPUPtr gpu = &vu->capabilities.gpu;
+    virJSONValuePtr featuresJSON;
+    size_t nfeatures;
+    size_t i;
+    VIR_AUTOPTR(qemuVhostUserGPUFeature) features = NULL;
+
+    if (!(featuresJSON = virJSONValueObjectGetArray(doc, "features"))) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("failed to get features from '%s'"),
+                       vu->binary);
+        return -1;
+    }
+
+    nfeatures = virJSONValueArraySize(featuresJSON);
+    if (VIR_ALLOC_N(features, nfeatures) < 0)
+        return -1;
+
+    for (i = 0; i < nfeatures; i++) {
+        virJSONValuePtr item = virJSONValueArrayGet(featuresJSON, i);
+        const char *tmpStr = virJSONValueGetString(item);
+        int tmp;
+
+        if ((tmp = qemuVhostUserGPUFeatureTypeFromString(tmpStr)) <= 0) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("unknown feature %s"),
+                           tmpStr);
+            continue;
+        }
+
+        features[i] = tmp;
+    }
+
+    VIR_STEAL_PTR(gpu->features, features);
+    gpu->nfeatures = nfeatures;
+
+    return 0;
+}
+
+
+static bool
+qemuVhostUserGPUHasFeature(qemuVhostUserGPUPtr gpu,
+                           qemuVhostUserGPUFeature feature)
+{
+    size_t i;
+
+    for (i = 0; i < gpu->nfeatures; i++) {
+        if (gpu->features[i] == feature)
+            return true;
+    }
+
+    return false;
+}
+
+
+int
+qemuVhostUserFillDomainGPU(virQEMUDriverPtr driver,
+                           virDomainVideoDefPtr video)
+{
+    qemuVhostUserPtr *vus = NULL;
+    ssize_t nvus = 0;
+    ssize_t i;
+    int ret = -1;
+
+    if ((nvus = qemuVhostUserFetchParsedConfigs(driver->privileged,
+                                                &vus, NULL)) < 0)
+        goto end;
+
+    for (i = 0; i < nvus; i++) {
+        qemuVhostUserPtr vu = vus[i];
+        VIR_AUTOPTR(virJSONValue) doc = NULL;
+        VIR_AUTOFREE(char *) output = NULL;
+        VIR_AUTOPTR(virCommand) cmd = NULL;
+
+        if (vu->type != QEMU_VHOST_USER_TYPE_GPU)
+            continue;
+
+        cmd = virCommandNewArgList(vu->binary, "--print-capabilities", NULL);
+        virCommandSetOutputBuffer(cmd, &output);
+        if (virCommandRun(cmd, NULL) < 0)
+            continue;
+
+        if (!(doc = virJSONValueFromString(output))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("unable to parse json capabilities '%s'"),
+                           vu->binary);
+            continue;
+        }
+
+        if (qemuVhostUserGPUFillCapabilities(vu, doc) < 0)
+            continue;
+
+        if (video->accel) {
+            if (video->accel->accel3d &&
+                !qemuVhostUserGPUHasFeature(&vu->capabilities.gpu,
+                                            QEMU_VHOST_USER_GPU_FEATURE_VIRGL))
+                continue;
+
+            if (video->accel->rendernode &&
+                !qemuVhostUserGPUHasFeature(&vu->capabilities.gpu,
+                                            QEMU_VHOST_USER_GPU_FEATURE_RENDER_NODE))
+                continue;
+        }
+
+        VIR_FREE(video->info.vhost_user_binary);
+        if (VIR_STRDUP(video->info.vhost_user_binary, vu->binary) < 0)
+            goto end;
+
+        ret = 0;
+        break;
+    }
+
+    if (i == nvus) {
+        virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+                       _("Unable to find a satisfying vhost-user-gpu"));
+    }
+
+ end:
+    for (i = 0; i < nvus; i++)
+        qemuVhostUserFree(vus[i]);
+    VIR_FREE(vus);
+    return ret;
+}
diff --git a/src/qemu/qemu_vhost_user.h b/src/qemu/qemu_vhost_user.h
new file mode 100644
index 0000000000..76701dd1fa
--- /dev/null
+++ b/src/qemu/qemu_vhost_user.h
@@ -0,0 +1,48 @@ 
+/*
+ * qemu_vhost_user.h: QEMU vhost-user
+ *
+ * Copyright (C) 2019 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "domain_conf.h"
+#include "qemu_conf.h"
+#include "virautoclean.h"
+#include "virarch.h"
+
+typedef struct _qemuVhostUser qemuVhostUser;
+typedef qemuVhostUser *qemuVhostUserPtr;
+
+void
+qemuVhostUserFree(qemuVhostUserPtr fw);
+
+VIR_DEFINE_AUTOPTR_FUNC(qemuVhostUser, qemuVhostUserFree);
+
+qemuVhostUserPtr
+qemuVhostUserParse(const char *path);
+
+char *
+qemuVhostUserFormat(qemuVhostUserPtr fw);
+
+int
+qemuVhostUserFetchConfigs(char ***configs,
+                         bool privileged);
+
+int
+qemuVhostUserFillDomainGPU(virQEMUDriverPtr driver,
+                           virDomainVideoDefPtr video);
diff --git a/tests/Makefile.am b/tests/Makefile.am
index f92710db43..4f4a5236ea 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -290,6 +290,7 @@  test_programs += qemuxml2argvtest qemuxml2xmltest \
 	qemumigparamstest \
 	qemusecuritytest \
 	qemufirmwaretest \
+	qemuvhostusertest \
 	$(NULL)
 test_helpers += qemucapsprobe
 test_libraries += libqemumonitortestutils.la \
@@ -692,6 +693,13 @@  qemufirmwaretest_SOURCES = \
 	$(NULL)
 qemufirmwaretest_LDADD = $(qemu_LDADDS)
 
+qemuvhostusertest_SOURCES = \
+	qemuvhostusertest.c \
+	testutils.h testutils.c \
+	virfilewrapper.c virfilewrapper.h \
+	$(NULL)
+qemuvhostusertest_LDADD = $(qemu_LDADDS)
+
 else ! WITH_QEMU
 EXTRA_DIST += qemuxml2argvtest.c qemuxml2xmltest.c \
 	qemudomaincheckpointxml2xmltest.c qemudomainsnapshotxml2xmltest.c \
@@ -706,6 +714,7 @@  EXTRA_DIST += qemuxml2argvtest.c qemuxml2xmltest.c \
 	qemusecuritytest.c qemusecuritytest.h \
 	qemusecuritymock.c \
 	qemufirmwaretest.c \
+	qemuvhostusertest.c \
 	$(QEMUMONITORTESTUTILS_SOURCES)
 endif ! WITH_QEMU
 
diff --git a/tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json b/tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json
new file mode 120000
index 0000000000..aa93864aa7
--- /dev/null
+++ b/tests/qemuvhostuserdata/etc/qemu/vhost-user/40-gpu.json
@@ -0,0 +1 @@ 
+../../../usr/share/qemu/vhost-user/50-gpu.json
\ No newline at end of file
diff --git a/tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json b/tests/qemuvhostuserdata/etc/qemu/vhost-user/50-gpu.json
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu b/tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu
new file mode 100755
index 0000000000..a2c2ee0713
--- /dev/null
+++ b/tests/qemuvhostuserdata/usr/libexec/qemu/vhost-user/test-vhost-user-gpu
@@ -0,0 +1,11 @@ 
+#!/bin/sh
+
+cat <<EOF
+{
+  "type": "gpu",
+  "features": [
+    "render-node",
+    "virgl"
+  ]
+}
+EOF
diff --git a/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json b/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json
new file mode 120000
index 0000000000..7051776593
--- /dev/null
+++ b/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/30-gpu.json
@@ -0,0 +1 @@ 
+50-gpu.json
\ No newline at end of file
diff --git a/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json b/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json
new file mode 100644
index 0000000000..4c751971db
--- /dev/null
+++ b/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/50-gpu.json
@@ -0,0 +1,8 @@ 
+{
+  "description": "QEMU vhost-user-gpu",
+  "type": "gpu",
+  "binary": "/usr/libexec/qemu/vhost-user/test-vhost-user-gpu",
+  "tags": [
+    "CONFIG_OPENGL_DMABUF=y"
+  ]
+}
diff --git a/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json b/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json
new file mode 120000
index 0000000000..7051776593
--- /dev/null
+++ b/tests/qemuvhostuserdata/usr/share/qemu/vhost-user/60-gpu.json
@@ -0,0 +1 @@ 
+50-gpu.json
\ No newline at end of file
diff --git a/tests/qemuvhostusertest.c b/tests/qemuvhostusertest.c
new file mode 100644
index 0000000000..52adf9834a
--- /dev/null
+++ b/tests/qemuvhostusertest.c
@@ -0,0 +1,132 @@ 
+#include <config.h>
+
+#include <inttypes.h>
+
+#include "testutils.h"
+#include "virfilewrapper.h"
+#include "qemu/qemu_vhost_user.h"
+#include "configmake.h"
+
+#define VIR_FROM_THIS VIR_FROM_QEMU
+
+/* A very basic test. Parse given JSON vhostuser description into
+ * an internal structure, format it back and compare with the
+ * contents of the file (minus some keys that are not parsed).
+ */
+static int
+testParseFormatVU(const void *opaque)
+{
+    const char *filename = opaque;
+    VIR_AUTOFREE(char *) path = NULL;
+    VIR_AUTOPTR(qemuVhostUser) vu = NULL;
+    VIR_AUTOFREE(char *) buf = NULL;
+    VIR_AUTOPTR(virJSONValue) json = NULL;
+    VIR_AUTOFREE(char *) expected = NULL;
+    VIR_AUTOFREE(char *) actual = NULL;
+
+    if (virAsprintf(&path, "%s/qemuvhostuserdata/%s",
+                    abs_srcdir, filename) < 0)
+        return -1;
+
+    if (!(vu = qemuVhostUserParse(path)))
+        return -1;
+
+    if (virFileReadAll(path,
+                       1024 * 1024, /* 1MiB */
+                       &buf) < 0)
+        return -1;
+
+    if (!(json = virJSONValueFromString(buf)))
+        return -1;
+
+    /* Description and tags are not parsed. */
+    if (virJSONValueObjectRemoveKey(json, "description", NULL) < 0 ||
+        virJSONValueObjectRemoveKey(json, "tags", NULL) < 0)
+        return -1;
+
+    if (!(expected = virJSONValueToString(json, true)))
+        return -1;
+
+    if (!(actual = qemuVhostUserFormat(vu)))
+        return -1;
+
+    return virTestCompareToString(expected, actual);
+}
+
+
+static int
+testVUPrecedence(const void *opaque ATTRIBUTE_UNUSED)
+{
+    VIR_AUTOFREE(char *) fakehome = NULL;
+    VIR_AUTOSTRINGLIST vuList = NULL;
+    size_t nvuList;
+    size_t i;
+    const char *expected[] = {
+        PREFIX "/share/qemu/vhost-user/30-gpu.json",
+        SYSCONFDIR "/qemu/vhost-user/40-gpu.json",
+        PREFIX "/share/qemu/vhost-user/60-gpu.json",
+    };
+    const size_t nexpected = ARRAY_CARDINALITY(expected);
+
+    if (VIR_STRDUP(fakehome, abs_srcdir "/qemuvhostuserdata/home/user/.config") < 0)
+        return -1;
+
+    setenv("XDG_CONFIG_HOME", fakehome, 1);
+
+    if (qemuVhostUserFetchConfigs(&vuList, false) < 0)
+        return -1;
+
+    if (!vuList) {
+        fprintf(stderr, "Expected a non-NULL result, but got a NULL result\n");
+        return -1;
+    }
+
+    nvuList = virStringListLength((const char **)vuList);
+
+    for (i = 0; i < MAX(nvuList, nexpected); i++) {
+        const char *e = i < nexpected ? expected[i] : NULL;
+        const char *f = i < nvuList ? vuList[i] : NULL;
+
+        if (STRNEQ_NULLABLE(e, f)) {
+            fprintf(stderr,
+                    "Unexpected path (i=%zu). Expected %s got %s \n",
+                    i, NULLSTR(e), NULLSTR(f));
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+
+static int
+mymain(void)
+{
+    int ret = 0;
+
+    virFileWrapperAddPrefix(SYSCONFDIR "/qemu/vhost-user",
+                            abs_srcdir "/qemuvhostuserdata/etc/qemu/vhost-user");
+    virFileWrapperAddPrefix(PREFIX "/share/qemu/vhost-user",
+                            abs_srcdir "/qemuvhostuserdata/usr/share/qemu/vhost-user");
+    virFileWrapperAddPrefix("/home/user/.config/qemu/vhost-user",
+                            abs_srcdir "/qemuvhostuserdata/home/user/.config/qemu/vhost-user");
+
+#define DO_PARSE_TEST(filename) \
+    do { \
+        if (virTestRun("QEMU vhost-user " filename, \
+                       testParseFormatVU, filename) < 0) \
+            ret = -1; \
+    } while (0)
+
+    DO_PARSE_TEST("usr/share/qemu/vhost-user/50-gpu.json");
+
+    if (virTestRun("QEMU vhost-user precedence test", testVUPrecedence, NULL) < 0)
+        ret = -1;
+
+    virFileWrapperClearPrefixes();
+
+    return ret == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
+}
+
+
+VIR_TEST_MAIN(mymain)