Linux Virtualization - Jun 2023 - [PATCH v1 2/2] vduse: enable Virtio-net device type

This small series enables virtio-net device type in VDUSE.
With it, basic operation have been tested, both with
virtio-vdpa and vhost-vdpa using DPDK Vhost library series
adding VDUSE support using split rings layout (merged in
DPDK v23.07-rc1).

Control queue support (and so multiqueue) has also been
tested, but requires a Kernel series from Jason Wang
relaxing control queue polling [1] to function reliably.

[1]:
https://lore.kernel.org/lkml/CACGkMEtgrxN3PPwsDo4oOsnsSLJfEmBEZ0WvjGRr3whU+QasUg
at mail.gmail.com/T/

RFC -> v1 changes:
=================- Fail device init if it does not support VERSION_1 (Jason)

Maxime Coquelin (2):
  vduse: validate block features only with block devices
  vduse: enable Virtio-net device type

 drivers/vdpa/vdpa_user/vduse_dev.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

-- 
2.41.0

This patch is preliminary work to enable network device
type support to VDUSE.

As VIRTIO_BLK_F_CONFIG_WCE shares the same value as
VIRTIO_NET_F_HOST_TSO4, we need to restrict its check
to Virtio-blk device type.

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 drivers/vdpa/vdpa_user/vduse_dev.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c
b/drivers/vdpa/vdpa_user/vduse_dev.c
index 5f5c21674fdc..c1c2f4c711ae 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -1658,13 +1658,14 @@ static bool device_is_allowed(u32 device_id)
 	return false;
 }
 
-static bool features_is_valid(u64 features)
+static bool features_is_valid(struct vduse_dev_config *config)
 {
-	if (!(features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
+	if (!(config->features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)))
 		return false;
 
 	/* Now we only support read-only configuration space */
-	if (features & (1ULL << VIRTIO_BLK_F_CONFIG_WCE))
+	if ((config->device_id == VIRTIO_ID_BLOCK) &&
+			(config->features & (1ULL << VIRTIO_BLK_F_CONFIG_WCE)))
 		return false;
 
 	return true;
@@ -1691,7 +1692,7 @@ static bool vduse_validate_config(struct vduse_dev_config
*config)
 	if (!device_is_allowed(config->device_id))
 		return false;
 
-	if (!features_is_valid(config->features))
+	if (!features_is_valid(config))
 		return false;
 
 	return true;
-- 
2.41.0

This patch adds Virtio-net device type to the supported
devices types. Initialization fails if the device does
not support VIRTIO_F_VERSION_1 feature, in order to
guarantee the configuration space is read-only.

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 drivers/vdpa/vdpa_user/vduse_dev.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c
b/drivers/vdpa/vdpa_user/vduse_dev.c
index c1c2f4c711ae..89088fa27026 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -142,6 +142,7 @@ static struct workqueue_struct *vduse_irq_bound_wq;
 
 static u32 allowed_device_id[] = {
 	VIRTIO_ID_BLOCK,
+	VIRTIO_ID_NET,
 };
 
 static inline struct vduse_dev *vdpa_to_vduse(struct vdpa_device *vdpa)
@@ -1668,6 +1669,10 @@ static bool features_is_valid(struct vduse_dev_config
*config)
 			(config->features & (1ULL << VIRTIO_BLK_F_CONFIG_WCE)))
 		return false;
 
+	if ((config->device_id == VIRTIO_ID_NET) &&
+			!(config->features & (1ULL << VIRTIO_F_VERSION_1)))
+		return false;
+
 	return true;
 }
 
@@ -2023,6 +2028,7 @@ static const struct vdpa_mgmtdev_ops vdpa_dev_mgmtdev_ops
= {
 
 static struct virtio_device_id id_table[] = {
 	{ VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
+	{ VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
 	{ 0 },
 };
 
-- 
2.41.0

On Tue, Jun 27, 2023 at 01:36:50PM +0200, Maxime Coquelin
wrote:
> This small series enables virtio-net device type in VDUSE.
> With it, basic operation have been tested, both with
> virtio-vdpa and vhost-vdpa using DPDK Vhost library series
> adding VDUSE support using split rings layout (merged in
> DPDK v23.07-rc1).
> 
> Control queue support (and so multiqueue) has also been
> tested, but requires a Kernel series from Jason Wang
> relaxing control queue polling [1] to function reliably.
> 
> [1]:
https://lore.kernel.org/lkml/CACGkMEtgrxN3PPwsDo4oOsnsSLJfEmBEZ0WvjGRr3whU+QasUg
at mail.gmail.com/T/
Jason promised to post a new version of that patch.
Right Jason?
For now let's make sure CVQ feature flag is off?
> RFC -> v1 changes:
> =================> - Fail device init if it does not support VERSION_1
(Jason)
> 
> Maxime Coquelin (2):
>   vduse: validate block features only with block devices
>   vduse: enable Virtio-net device type
> 
>  drivers/vdpa/vdpa_user/vduse_dev.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> -- 
> 2.41.0

On Tue, Jun 27, 2023 at 01:36:50PM +0200, Maxime Coquelin
wrote:
> This small series enables virtio-net device type in VDUSE.
> With it, basic operation have been tested, both with
> virtio-vdpa and vhost-vdpa using DPDK Vhost library series
> adding VDUSE support using split rings layout (merged in
> DPDK v23.07-rc1).
> 
> Control queue support (and so multiqueue) has also been
> tested, but requires a Kernel series from Jason Wang
> relaxing control queue polling [1] to function reliably.
> 
> [1]:
https://lore.kernel.org/lkml/CACGkMEtgrxN3PPwsDo4oOsnsSLJfEmBEZ0WvjGRr3whU+QasUg
at mail.gmail.com/T/
> 
> RFC -> v1 changes:
> =================> - Fail device init if it does not support VERSION_1
(Jason)
So I can put this in next, the issue I think is
that of security: currently selinux can if necessary block
access to creating virtio block devices.
But if we have more than one type we need a way for selinux to
block specific types. Can be a patch on top but pls work to
address.

Another question is that with this userspace can inject
packets directly into net stack. Should we check CAP_NET_ADMIN
or such?

> Maxime Coquelin (2):
>   vduse: validate block features only with block devices
>   vduse: enable Virtio-net device type
> 
>  drivers/vdpa/vdpa_user/vduse_dev.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> -- 
> 2.41.0