Provide extended version of the features manipulation helpers,
and let the device initialization deal with the full features space,
adjusting the relevant format strings accordingly.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
v2 -> v3:
- use virtio_features_andnot return value instead of virtio_features_empty
- rebased on top of "net: Consolidate vhost feature bits into vhost_net
structure"
- _array -> _ex
v1 -> v2:
- uint128_t -> uint64_t[]
- provide extended variant of the features manipulation helpers
---
hw/net/vhost_net-stub.c | 8 +++----
hw/net/vhost_net.c | 46 ++++++++++++++++++++++-------------------
include/net/vhost_net.h | 33 ++++++++++++++++++++++++++---
3 files changed, 58 insertions(+), 29 deletions(-)
diff --git a/hw/net/vhost_net-stub.c b/hw/net/vhost_net-stub.c
index 7d49f82906..0740d5a2eb 100644
--- a/hw/net/vhost_net-stub.c
+++ b/hw/net/vhost_net-stub.c
@@ -46,9 +46,8 @@ void vhost_net_cleanup(struct vhost_net *net)
{
}
-uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
+void vhost_net_get_features_ex(struct vhost_net *net, uint64_t *features)
{
- return features;
}
int vhost_net_get_config(struct vhost_net *net, uint8_t *config,
@@ -62,13 +61,12 @@ int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
return 0;
}
-void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
+void vhost_net_ack_features_ex(struct vhost_net *net, const uint64_t *features)
{
}
-uint64_t vhost_net_get_acked_features(VHostNetState *net)
+void vhost_net_get_acked_features_ex(VHostNetState *net, uint64_t *features)
{
- return 0;
}
bool vhost_net_virtqueue_pending(VHostNetState *net, int idx)
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 540492b37d..33fc6ba2f9 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -35,10 +35,9 @@
#include "hw/virtio/virtio-bus.h"
#include "linux-headers/linux/vhost.h"
-uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
+void vhost_net_get_features_ex(struct vhost_net *net, uint64_t *features)
{
- return vhost_get_features(&net->dev, net->feature_bits,
- features);
+ vhost_get_features_ex(&net->dev, net->feature_bits, features);
}
int vhost_net_get_config(struct vhost_net *net, uint8_t *config,
uint32_t config_len)
@@ -51,10 +50,11 @@ int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
return vhost_dev_set_config(&net->dev, data, offset, size, flags);
}
-void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
+void vhost_net_ack_features_ex(struct vhost_net *net, const uint64_t *features)
{
- net->dev.acked_features = net->dev.backend_features;
- vhost_ack_features(&net->dev, net->feature_bits, features);
+ virtio_features_copy(net->dev.acked_features_ex,
+ net->dev.backend_features_ex);
+ vhost_ack_features_ex(&net->dev, net->feature_bits, features);
}
uint64_t vhost_net_get_max_queues(VHostNetState *net)
@@ -62,9 +62,9 @@ uint64_t vhost_net_get_max_queues(VHostNetState *net)
return net->dev.max_queues;
}
-uint64_t vhost_net_get_acked_features(VHostNetState *net)
+void vhost_net_get_acked_features_ex(VHostNetState *net, uint64_t *features)
{
- return net->dev.acked_features;
+ virtio_features_copy(features, net->dev.acked_features_ex);
}
void vhost_net_save_acked_features(NetClientState *nc)
@@ -234,7 +234,8 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
int r;
bool backend_kernel = options->backend_type == VHOST_BACKEND_TYPE_KERNEL;
struct vhost_net *net = g_new0(struct vhost_net, 1);
- uint64_t features = 0;
+ uint64_t missing_features[VIRTIO_FEATURES_DWORDS];
+ uint64_t features[VIRTIO_FEATURES_DWORDS];
Error *local_err = NULL;
if (!options->net_backend) {
@@ -261,7 +262,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
net->backend = r;
net->dev.protocol_features = 0;
} else {
- net->dev.backend_features = 0;
+ virtio_features_clear(net->dev.backend_features_ex);
net->dev.protocol_features = 0;
net->backend = -1;
@@ -279,28 +280,31 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
if (backend_kernel) {
if (!qemu_has_vnet_hdr_len(options->net_backend,
sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
- net->dev.features &= ~(1ULL << VIRTIO_NET_F_MRG_RXBUF);
+ net->dev.features &= ~VIRTIO_BIT(VIRTIO_NET_F_MRG_RXBUF);
}
- if (~net->dev.features & net->dev.backend_features) {
- fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
- " for backend\n",
- (uint64_t)(~net->dev.features & net->dev.backend_features));
+
+ if (virtio_features_andnot(missing_features,
+ net->dev.backend_features_ex,
+ net->dev.features_ex)) {
+ fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
+ " for backend\n", VIRTIO_FEATURES_PR(missing_features));
goto fail;
}
}
/* Set sane init value. Override when guest acks. */
if (options->get_acked_features) {
- features = options->get_acked_features(net->nc);
- if (~net->dev.features & features) {
- fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
- " for backend\n",
- (uint64_t)(~net->dev.features & features));
+ virtio_features_from_u64(features,
+ options->get_acked_features(net->nc));
+ if (virtio_features_andnot(missing_features, features,
+ net->dev.features_ex)) {
+ fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
+ " for backend\n", VIRTIO_FEATURES_PR(missing_features));
goto fail;
}
}
- vhost_net_ack_features(net, features);
+ vhost_net_ack_features_ex(net, features);
return net;
diff --git a/include/net/vhost_net.h b/include/net/vhost_net.h
index 879781dad7..1d07b437c7 100644
--- a/include/net/vhost_net.h
+++ b/include/net/vhost_net.h
@@ -2,6 +2,7 @@
#define VHOST_NET_H
#include "net/net.h"
+#include "hw/virtio/virtio-features.h"
#include "hw/virtio/vhost-backend.h"
struct vhost_net;
@@ -33,8 +34,26 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
void vhost_net_cleanup(VHostNetState *net);
-uint64_t vhost_net_get_features(VHostNetState *net, uint64_t features);
-void vhost_net_ack_features(VHostNetState *net, uint64_t features);
+void vhost_net_get_features_ex(VHostNetState *net, uint64_t *features);
+static inline uint64_t vhost_net_get_features(VHostNetState *net,
+ uint64_t features)
+{
+ uint64_t features_array[VIRTIO_FEATURES_DWORDS];
+
+ virtio_features_from_u64(features_array, features);
+ vhost_net_get_features_ex(net, features_array);
+ return features_array[0];
+}
+
+void vhost_net_ack_features_ex(VHostNetState *net, const uint64_t *features);
+static inline void vhost_net_ack_features(VHostNetState *net,
+ uint64_t features)
+{
+ uint64_t features_array[VIRTIO_FEATURES_DWORDS];
+
+ virtio_features_from_u64(features_array, features);
+ vhost_net_ack_features_ex(net, features_array);
+}
int vhost_net_get_config(struct vhost_net *net, uint8_t *config,
uint32_t config_len);
@@ -51,7 +70,15 @@ VHostNetState *get_vhost_net(NetClientState *nc);
int vhost_net_set_vring_enable(NetClientState *nc, int enable);
-uint64_t vhost_net_get_acked_features(VHostNetState *net);
+void vhost_net_get_acked_features_ex(VHostNetState *net, uint64_t *features);
+static inline uint64_t vhost_net_get_acked_features(VHostNetState *net)
+{
+ uint64_t features[VIRTIO_FEATURES_DWORDS];
+
+ vhost_net_get_acked_features_ex(net, features);
+ assert(!virtio_features_use_extended(features));
+ return features[0];
+}
int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu);
--
2.50.0On Fri, Jul 18, 2025 at 10:52:36AM +0200, Paolo Abeni wrote:
>Provide extended version of the features manipulation helpers,
>and let the device initialization deal with the full features space,
>adjusting the relevant format strings accordingly.
>
>Signed-off-by: Paolo Abeni <pabeni@redhat.com>
>---
>v2 -> v3:
> - use virtio_features_andnot return value instead of virtio_features_empty
> - rebased on top of "net: Consolidate vhost feature bits into vhost_net
> structure"
> - _array -> _ex
>
>v1 -> v2:
> - uint128_t -> uint64_t[]
> - provide extended variant of the features manipulation helpers
>---
> hw/net/vhost_net-stub.c | 8 +++----
> hw/net/vhost_net.c | 46 ++++++++++++++++++++++-------------------
> include/net/vhost_net.h | 33 ++++++++++++++++++++++++++---
> 3 files changed, 58 insertions(+), 29 deletions(-)
>
>diff --git a/hw/net/vhost_net-stub.c b/hw/net/vhost_net-stub.c
>index 7d49f82906..0740d5a2eb 100644
>--- a/hw/net/vhost_net-stub.c
>+++ b/hw/net/vhost_net-stub.c
>@@ -46,9 +46,8 @@ void vhost_net_cleanup(struct vhost_net *net)
> {
> }
>
>-uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
>+void vhost_net_get_features_ex(struct vhost_net *net, uint64_t *features)
> {
>- return features;
> }
>
> int vhost_net_get_config(struct vhost_net *net, uint8_t *config,
>@@ -62,13 +61,12 @@ int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
> return 0;
> }
>
>-void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
>+void vhost_net_ack_features_ex(struct vhost_net *net, const uint64_t *features)
> {
> }
>
>-uint64_t vhost_net_get_acked_features(VHostNetState *net)
>+void vhost_net_get_acked_features_ex(VHostNetState *net, uint64_t *features)
> {
>- return 0;
> }
>
> bool vhost_net_virtqueue_pending(VHostNetState *net, int idx)
>diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
>index 540492b37d..33fc6ba2f9 100644
>--- a/hw/net/vhost_net.c
>+++ b/hw/net/vhost_net.c
>@@ -35,10 +35,9 @@
> #include "hw/virtio/virtio-bus.h"
> #include "linux-headers/linux/vhost.h"
>
>-uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
>+void vhost_net_get_features_ex(struct vhost_net *net, uint64_t *features)
> {
>- return vhost_get_features(&net->dev, net->feature_bits,
>- features);
>+ vhost_get_features_ex(&net->dev, net->feature_bits, features);
> }
> int vhost_net_get_config(struct vhost_net *net, uint8_t *config,
> uint32_t config_len)
>@@ -51,10 +50,11 @@ int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
> return vhost_dev_set_config(&net->dev, data, offset, size, flags);
> }
>
>-void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
>+void vhost_net_ack_features_ex(struct vhost_net *net, const uint64_t *features)
> {
>- net->dev.acked_features = net->dev.backend_features;
>- vhost_ack_features(&net->dev, net->feature_bits, features);
>+ virtio_features_copy(net->dev.acked_features_ex,
>+ net->dev.backend_features_ex);
>+ vhost_ack_features_ex(&net->dev, net->feature_bits, features);
> }
>
> uint64_t vhost_net_get_max_queues(VHostNetState *net)
>@@ -62,9 +62,9 @@ uint64_t vhost_net_get_max_queues(VHostNetState *net)
> return net->dev.max_queues;
> }
>
>-uint64_t vhost_net_get_acked_features(VHostNetState *net)
>+void vhost_net_get_acked_features_ex(VHostNetState *net, uint64_t *features)
> {
>- return net->dev.acked_features;
>+ virtio_features_copy(features, net->dev.acked_features_ex);
> }
>
> void vhost_net_save_acked_features(NetClientState *nc)
>@@ -234,7 +234,8 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
> int r;
> bool backend_kernel = options->backend_type == VHOST_BACKEND_TYPE_KERNEL;
> struct vhost_net *net = g_new0(struct vhost_net, 1);
>- uint64_t features = 0;
>+ uint64_t missing_features[VIRTIO_FEATURES_DWORDS];
>+ uint64_t features[VIRTIO_FEATURES_DWORDS];
Should we initialize `features` (IIUC calling virtio_features_clear)
since it was set to 0 before this patch?
> Error *local_err = NULL;
>
> if (!options->net_backend) {
>@@ -261,7 +262,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
> net->backend = r;
> net->dev.protocol_features = 0;
> } else {
>- net->dev.backend_features = 0;
>+ virtio_features_clear(net->dev.backend_features_ex);
> net->dev.protocol_features = 0;
> net->backend = -1;
>
>@@ -279,28 +280,31 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
> if (backend_kernel) {
> if (!qemu_has_vnet_hdr_len(options->net_backend,
> sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
>- net->dev.features &= ~(1ULL << VIRTIO_NET_F_MRG_RXBUF);
>+ net->dev.features &= ~VIRTIO_BIT(VIRTIO_NET_F_MRG_RXBUF);
> }
>- if (~net->dev.features & net->dev.backend_features) {
>- fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
>- " for backend\n",
>- (uint64_t)(~net->dev.features & net->dev.backend_features));
>+
>+ if (virtio_features_andnot(missing_features,
>+ net->dev.backend_features_ex,
>+ net->dev.features_ex)) {
>+ fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
>+ " for backend\n", VIRTIO_FEATURES_PR(missing_features));
> goto fail;
> }
> }
>
> /* Set sane init value. Override when guest acks. */
> if (options->get_acked_features) {
>- features = options->get_acked_features(net->nc);
>- if (~net->dev.features & features) {
>- fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
>- " for backend\n",
>- (uint64_t)(~net->dev.features & features));
>+ virtio_features_from_u64(features,
>+ options->get_acked_features(net->nc));
>+ if (virtio_features_andnot(missing_features, features,
>+ net->dev.features_ex)) {
>+ fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
>+ " for backend\n", VIRTIO_FEATURES_PR(missing_features));
> goto fail;
> }
> }
>
>- vhost_net_ack_features(net, features);
>+ vhost_net_ack_features_ex(net, features);
If `options->get_acked_features` is false, `features` here is not
initialized (it was set to 0 before this patch).
Thanks,
Stefano
>
> return net;
>
>diff --git a/include/net/vhost_net.h b/include/net/vhost_net.h
>index 879781dad7..1d07b437c7 100644
>--- a/include/net/vhost_net.h
>+++ b/include/net/vhost_net.h
>@@ -2,6 +2,7 @@
> #define VHOST_NET_H
>
> #include "net/net.h"
>+#include "hw/virtio/virtio-features.h"
> #include "hw/virtio/vhost-backend.h"
>
> struct vhost_net;
>@@ -33,8 +34,26 @@ void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
>
> void vhost_net_cleanup(VHostNetState *net);
>
>-uint64_t vhost_net_get_features(VHostNetState *net, uint64_t features);
>-void vhost_net_ack_features(VHostNetState *net, uint64_t features);
>+void vhost_net_get_features_ex(VHostNetState *net, uint64_t *features);
>+static inline uint64_t vhost_net_get_features(VHostNetState *net,
>+ uint64_t features)
>+{
>+ uint64_t features_array[VIRTIO_FEATURES_DWORDS];
>+
>+ virtio_features_from_u64(features_array, features);
>+ vhost_net_get_features_ex(net, features_array);
>+ return features_array[0];
>+}
>+
>+void vhost_net_ack_features_ex(VHostNetState *net, const uint64_t *features);
>+static inline void vhost_net_ack_features(VHostNetState *net,
>+ uint64_t features)
>+{
>+ uint64_t features_array[VIRTIO_FEATURES_DWORDS];
>+
>+ virtio_features_from_u64(features_array, features);
>+ vhost_net_ack_features_ex(net, features_array);
>+}
>
> int vhost_net_get_config(struct vhost_net *net, uint8_t *config,
> uint32_t config_len);
>@@ -51,7 +70,15 @@ VHostNetState *get_vhost_net(NetClientState *nc);
>
> int vhost_net_set_vring_enable(NetClientState *nc, int enable);
>
>-uint64_t vhost_net_get_acked_features(VHostNetState *net);
>+void vhost_net_get_acked_features_ex(VHostNetState *net, uint64_t *features);
>+static inline uint64_t vhost_net_get_acked_features(VHostNetState *net)
>+{
>+ uint64_t features[VIRTIO_FEATURES_DWORDS];
>+
>+ vhost_net_get_acked_features_ex(net, features);
>+ assert(!virtio_features_use_extended(features));
>+ return features[0];
>+}
>
> int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu);
>
>--
>2.50.0
>
On 7/18/25 3:01 PM, Stefano Garzarella wrote:
> On Fri, Jul 18, 2025 at 10:52:36AM +0200, Paolo Abeni wrote:
>> @@ -234,7 +234,8 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
>> int r;
>> bool backend_kernel = options->backend_type == VHOST_BACKEND_TYPE_KERNEL;
>> struct vhost_net *net = g_new0(struct vhost_net, 1);
>> - uint64_t features = 0;
>> + uint64_t missing_features[VIRTIO_FEATURES_DWORDS];
>> + uint64_t features[VIRTIO_FEATURES_DWORDS];
>
> Should we initialize `features` (IIUC calling virtio_features_clear)
> since it was set to 0 before this patch?
>
>> Error *local_err = NULL;
>>
>> if (!options->net_backend) {
>> @@ -261,7 +262,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
>> net->backend = r;
>> net->dev.protocol_features = 0;
>> } else {
>> - net->dev.backend_features = 0;
>> + virtio_features_clear(net->dev.backend_features_ex);
>> net->dev.protocol_features = 0;
>> net->backend = -1;
>>
>> @@ -279,28 +280,31 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
>> if (backend_kernel) {
>> if (!qemu_has_vnet_hdr_len(options->net_backend,
>> sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
>> - net->dev.features &= ~(1ULL << VIRTIO_NET_F_MRG_RXBUF);
>> + net->dev.features &= ~VIRTIO_BIT(VIRTIO_NET_F_MRG_RXBUF);
>> }
>> - if (~net->dev.features & net->dev.backend_features) {
>> - fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
>> - " for backend\n",
>> - (uint64_t)(~net->dev.features & net->dev.backend_features));
>> +
>> + if (virtio_features_andnot(missing_features,
>> + net->dev.backend_features_ex,
>> + net->dev.features_ex)) {
>> + fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
>> + " for backend\n", VIRTIO_FEATURES_PR(missing_features));
>> goto fail;
>> }
>> }
>>
>> /* Set sane init value. Override when guest acks. */
>> if (options->get_acked_features) {
>> - features = options->get_acked_features(net->nc);
>> - if (~net->dev.features & features) {
>> - fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
>> - " for backend\n",
>> - (uint64_t)(~net->dev.features & features));
>> + virtio_features_from_u64(features,
>> + options->get_acked_features(net->nc));
>> + if (virtio_features_andnot(missing_features, features,
>> + net->dev.features_ex)) {
>> + fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
>> + " for backend\n", VIRTIO_FEATURES_PR(missing_features));
>> goto fail;
>> }
>> }
>>
>> - vhost_net_ack_features(net, features);
>> + vhost_net_ack_features_ex(net, features);
>
> If `options->get_acked_features` is false, `features` here is not
> initialized (it was set to 0 before this patch).
Indeed the initialization is needed. I will fix the next revision.
Thanks,
Paolo
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