Similar to virtio infra, vhost core maintains the features status
in the full extended format and allows the devices to implement
extended version of the getter/setter.
Note that 'protocol_features' are not extended: they are only
used by vhost-user, and the latter device is not going to implement
extended features soon.
Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
v3 -> v4:
- fix compile warning for real :(
- de-duplicate code from vhost_{get,ack}_features and
vhost_{get,ack}_features_ex
- use new virtio_features macro names
v2 -> v3:
- fix compile warning
- _array -> _ex
v1 -> v2:
- uint128_t -> uint64_t[]
- add _ex() variant of features manipulation helpers
---
hw/virtio/vhost.c | 68 ++++++++++++++++++++++---------
include/hw/virtio/vhost-backend.h | 6 +++
include/hw/virtio/vhost.h | 56 +++++++++++++++++++++----
3 files changed, 103 insertions(+), 27 deletions(-)
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 6557c58d12..5f485ad6cb 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -972,20 +972,34 @@ static int vhost_virtqueue_set_addr(struct vhost_dev *dev,
static int vhost_dev_set_features(struct vhost_dev *dev,
bool enable_log)
{
- uint64_t features = dev->acked_features;
+ uint64_t features[VIRTIO_FEATURES_NU64S];
int r;
+
+ virtio_features_copy(features, dev->acked_features_ex);
if (enable_log) {
- features |= 0x1ULL << VHOST_F_LOG_ALL;
+ virtio_add_feature_ex(features, VHOST_F_LOG_ALL);
}
if (!vhost_dev_has_iommu(dev)) {
- features &= ~(0x1ULL << VIRTIO_F_IOMMU_PLATFORM);
+ virtio_clear_feature_ex(features, VIRTIO_F_IOMMU_PLATFORM);
}
if (dev->vhost_ops->vhost_force_iommu) {
if (dev->vhost_ops->vhost_force_iommu(dev) == true) {
- features |= 0x1ULL << VIRTIO_F_IOMMU_PLATFORM;
+ virtio_add_feature_ex(features, VIRTIO_F_IOMMU_PLATFORM);
}
}
- r = dev->vhost_ops->vhost_set_features(dev, features);
+
+ if (virtio_features_use_ex(features) &&
+ !dev->vhost_ops->vhost_set_features_ex) {
+ r = -EINVAL;
+ VHOST_OPS_DEBUG(r, "extended features without device support");
+ goto out;
+ }
+
+ if (dev->vhost_ops->vhost_set_features_ex) {
+ r = dev->vhost_ops->vhost_set_features_ex(dev, features);
+ } else {
+ r = dev->vhost_ops->vhost_set_features(dev, features[0]);
+ }
if (r < 0) {
VHOST_OPS_DEBUG(r, "vhost_set_features failed");
goto out;
@@ -1508,12 +1522,27 @@ static void vhost_virtqueue_cleanup(struct
vhost_virtqueue *vq)
}
}
+static int vhost_dev_get_features(struct vhost_dev *hdev,
+ uint64_t *features)
+{
+ uint64_t features64;
+ int r;
+
+ if (hdev->vhost_ops->vhost_get_features_ex) {
+ return hdev->vhost_ops->vhost_get_features_ex(hdev, features);
+ }
+
+ r = hdev->vhost_ops->vhost_get_features(hdev, &features64);
+ virtio_features_from_u64(features, features64);
+ return r;
+}
+
int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
VhostBackendType backend_type, uint32_t busyloop_timeout,
Error **errp)
{
+ uint64_t features[VIRTIO_FEATURES_NU64S];
unsigned int used, reserved, limit;
- uint64_t features;
int i, r, n_initialized_vqs = 0;
hdev->vdev = NULL;
@@ -1533,7 +1562,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
goto fail;
}
- r = hdev->vhost_ops->vhost_get_features(hdev, &features);
+ r = vhost_dev_get_features(hdev, features);
if (r < 0) {
error_setg_errno(errp, -r, "vhost_get_features failed");
goto fail;
@@ -1571,7 +1600,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
}
}
- hdev->features = features;
+ virtio_features_copy(hdev->features_ex, features);
hdev->memory_listener = (MemoryListener) {
.name = "vhost",
@@ -1594,7 +1623,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
};
if (hdev->migration_blocker == NULL) {
- if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) {
+ if (!virtio_has_feature_ex(hdev->features_ex, VHOST_F_LOG_ALL)) {
error_setg(&hdev->migration_blocker,
"Migration disabled: vhost lacks VHOST_F_LOG_ALL
feature.");
} else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check())
{
@@ -1859,28 +1888,27 @@ static void vhost_start_config_intr(struct vhost_dev
*dev)
}
}
-uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits,
- uint64_t features)
+void vhost_get_features_ex(struct vhost_dev *hdev,
+ const int *feature_bits,
+ uint64_t *features)
{
const int *bit = feature_bits;
+
while (*bit != VHOST_INVALID_FEATURE_BIT) {
- uint64_t bit_mask = (1ULL << *bit);
- if (!(hdev->features & bit_mask)) {
- features &= ~bit_mask;
+ if (!virtio_has_feature_ex(hdev->features_ex, *bit)) {
+ virtio_clear_feature_ex(features, *bit);
}
bit++;
}
- return features;
}
-void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits,
- uint64_t features)
+void vhost_ack_features_ex(struct vhost_dev *hdev, const int *feature_bits,
+ const uint64_t *features)
{
const int *bit = feature_bits;
while (*bit != VHOST_INVALID_FEATURE_BIT) {
- uint64_t bit_mask = (1ULL << *bit);
- if (features & bit_mask) {
- hdev->acked_features |= bit_mask;
+ if (virtio_has_feature_ex(features, *bit)) {
+ virtio_add_feature_ex(hdev->acked_features_ex, *bit);
}
bit++;
}
diff --git a/include/hw/virtio/vhost-backend.h
b/include/hw/virtio/vhost-backend.h
index d6df209a2f..ff94fa1734 100644
--- a/include/hw/virtio/vhost-backend.h
+++ b/include/hw/virtio/vhost-backend.h
@@ -95,6 +95,10 @@ typedef int (*vhost_new_worker_op)(struct vhost_dev *dev,
struct vhost_worker_state *worker);
typedef int (*vhost_free_worker_op)(struct vhost_dev *dev,
struct vhost_worker_state *worker);
+typedef int (*vhost_set_features_ex_op)(struct vhost_dev *dev,
+ const uint64_t *features);
+typedef int (*vhost_get_features_ex_op)(struct vhost_dev *dev,
+ uint64_t *features);
typedef int (*vhost_set_features_op)(struct vhost_dev *dev,
uint64_t features);
typedef int (*vhost_get_features_op)(struct vhost_dev *dev,
@@ -186,6 +190,8 @@ typedef struct VhostOps {
vhost_free_worker_op vhost_free_worker;
vhost_get_vring_worker_op vhost_get_vring_worker;
vhost_attach_vring_worker_op vhost_attach_vring_worker;
+ vhost_set_features_ex_op vhost_set_features_ex;
+ vhost_get_features_ex_op vhost_get_features_ex;
vhost_set_features_op vhost_set_features;
vhost_get_features_op vhost_get_features;
vhost_set_backend_cap_op vhost_set_backend_cap;
diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
index 66be6afc88..08bbb4dfe9 100644
--- a/include/hw/virtio/vhost.h
+++ b/include/hw/virtio/vhost.h
@@ -107,9 +107,9 @@ struct vhost_dev {
* future use should be discouraged and the variable retired as
* its easy to confuse with the VirtIO backend_features.
*/
- uint64_t features;
- uint64_t acked_features;
- uint64_t backend_features;
+ VIRTIO_DECLARE_FEATURES(features);
+ VIRTIO_DECLARE_FEATURES(acked_features);
+ VIRTIO_DECLARE_FEATURES(backend_features);
/**
* @protocol_features: is the vhost-user only feature set by
@@ -320,6 +320,20 @@ bool vhost_virtqueue_pending(struct vhost_dev *hdev, int
n);
void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n,
bool mask);
+/**
+ * vhost_get_features_ex() - sanitize the extended features set
+ * @hdev: common vhost_dev structure
+ * @feature_bits: pointer to terminated table of feature bits
+ * @features: original features set, filtered out on return
+ *
+ * This is the extended variant of vhost_get_features(), supporting the
+ * the extended features set. Filter it with the intersection of what is
+ * supported by the vhost backend (hdev->features) and the supported
+ * feature_bits.
+ */
+void vhost_get_features_ex(struct vhost_dev *hdev,
+ const int *feature_bits,
+ uint64_t *features);
/**
* vhost_get_features() - return a sanitised set of feature bits
* @hdev: common vhost_dev structure
@@ -330,8 +344,28 @@ void vhost_virtqueue_mask(struct vhost_dev *hdev,
VirtIODevice *vdev, int n,
* is supported by the vhost backend (hdev->features), the supported
* feature_bits and the requested feature set.
*/
-uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits,
- uint64_t features);
+static inline uint64_t vhost_get_features(struct vhost_dev *hdev,
+ const int *feature_bits,
+ uint64_t features)
+{
+ uint64_t features_ex[VIRTIO_FEATURES_NU64S];
+
+ virtio_features_from_u64(features_ex, features);
+ vhost_get_features_ex(hdev, feature_bits, features_ex);
+ return features_ex[0];
+}
+
+/**
+ * vhost_ack_features_ex() - set vhost full set of acked_features
+ * @hdev: common vhost_dev structure
+ * @feature_bits: pointer to terminated table of feature bits
+ * @features: requested feature set
+ *
+ * This sets the internal hdev->acked_features to the intersection of
+ * the backends advertised features and the supported feature_bits.
+ */
+void vhost_ack_features_ex(struct vhost_dev *hdev, const int *feature_bits,
+ const uint64_t *features);
/**
* vhost_ack_features() - set vhost acked_features
@@ -342,8 +376,16 @@ uint64_t vhost_get_features(struct vhost_dev *hdev, const
int *feature_bits,
* This sets the internal hdev->acked_features to the intersection of
* the backends advertised features and the supported feature_bits.
*/
-void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits,
- uint64_t features);
+static inline void vhost_ack_features(struct vhost_dev *hdev,
+ const int *feature_bits,
+ uint64_t features)
+{
+ uint64_t features_ex[VIRTIO_FEATURES_NU64S];
+
+ virtio_features_from_u64(features_ex, features);
+ vhost_ack_features_ex(hdev, feature_bits, features_ex);
+}
+
unsigned int vhost_get_max_memslots(void);
unsigned int vhost_get_free_memslots(void);
--
2.50.1
