Alvaro Karsz
2023-Apr-13 08:18 UTC
[PATCH 0/2] virtio: add VIRTIO_F_NOTIFICATION_DATA feature support
Add VIRTIO_F_NOTIFICATION_DATA feature support for the MMIO, channel I/O, modern PCI and vDPA transports. This patchset binds 2 patches that were sent separately to the mailing lists. The first one [1] adds support for the MMIO, channel I/O and modern PCI transports. The second one [2] adds support to the vDPA transport. [1] https://lore.kernel.org/lkml/20230324195029.2410503-1-viktor at daynix.com/ [2] https://lore.kernel.org/virtualization/20230409070706.3288876-1-alvaro.karsz at solid-run.com/ Alvaro Karsz (1): virtio-vdpa: add VIRTIO_F_NOTIFICATION_DATA feature support Viktor Prutyanov (1): virtio: add VIRTIO_F_NOTIFICATION_DATA feature support drivers/s390/virtio/virtio_ccw.c | 22 +++++++++++++++++++--- drivers/virtio/virtio_mmio.c | 18 +++++++++++++++++- drivers/virtio/virtio_pci_modern.c | 17 ++++++++++++++++- drivers/virtio/virtio_ring.c | 19 +++++++++++++++++++ drivers/virtio/virtio_vdpa.c | 23 +++++++++++++++++++++-- include/linux/vdpa.h | 9 +++++++++ include/linux/virtio_ring.h | 2 ++ include/uapi/linux/virtio_config.h | 6 ++++++ 8 files changed, 109 insertions(+), 7 deletions(-) -- 2.34.1
Alvaro Karsz
2023-Apr-13 08:18 UTC
[PATCH 1/2] virtio: add VIRTIO_F_NOTIFICATION_DATA feature support
From: Viktor Prutyanov <viktor at daynix.com>
According to VirtIO spec v1.2, VIRTIO_F_NOTIFICATION_DATA feature
indicates that the driver passes extra data along with the queue
notifications.
In a split queue case, the extra data is 16-bit available index. In a
packed queue case, the extra data is 1-bit wrap counter and 15-bit
available index.
Add support for this feature for MMIO, channel I/O and modern PCI
transports.
Signed-off-by: Viktor Prutyanov <viktor at daynix.com>
Acked-by: Jason Wang <jasowang at redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
drivers/s390/virtio/virtio_ccw.c | 22 +++++++++++++++++++---
drivers/virtio/virtio_mmio.c | 18 +++++++++++++++++-
drivers/virtio/virtio_pci_modern.c | 17 ++++++++++++++++-
drivers/virtio/virtio_ring.c | 19 +++++++++++++++++++
include/linux/virtio_ring.h | 2 ++
include/uapi/linux/virtio_config.h | 6 ++++++
6 files changed, 79 insertions(+), 5 deletions(-)
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index 954fc31b4bc..02922768b12 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -391,7 +391,7 @@ static void virtio_ccw_drop_indicator(struct
virtio_ccw_device *vcdev,
ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
}
-static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
+static inline bool virtio_ccw_do_kvm_notify(struct virtqueue *vq, u32 data)
{
struct virtio_ccw_vq_info *info = vq->priv;
struct virtio_ccw_device *vcdev;
@@ -402,12 +402,22 @@ static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY,
*((unsigned int *)&schid),
- vq->index, info->cookie);
+ data, info->cookie);
if (info->cookie < 0)
return false;
return true;
}
+static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
+{
+ return virtio_ccw_do_kvm_notify(vq, vq->index);
+}
+
+static bool virtio_ccw_kvm_notify_with_data(struct virtqueue *vq)
+{
+ return virtio_ccw_do_kvm_notify(vq, vring_notification_data(vq));
+}
+
static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
struct ccw1 *ccw, int index)
{
@@ -495,6 +505,7 @@ static struct virtqueue *virtio_ccw_setup_vq(struct
virtio_device *vdev,
struct ccw1 *ccw)
{
struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ bool (*notify)(struct virtqueue *vq);
int err;
struct virtqueue *vq = NULL;
struct virtio_ccw_vq_info *info;
@@ -502,6 +513,11 @@ static struct virtqueue *virtio_ccw_setup_vq(struct
virtio_device *vdev,
unsigned long flags;
bool may_reduce;
+ if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA))
+ notify = virtio_ccw_kvm_notify_with_data;
+ else
+ notify = virtio_ccw_kvm_notify;
+
/* Allocate queue. */
info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
if (!info) {
@@ -524,7 +540,7 @@ static struct virtqueue *virtio_ccw_setup_vq(struct
virtio_device *vdev,
may_reduce = vcdev->revision > 0;
vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
vdev, true, may_reduce, ctx,
- virtio_ccw_kvm_notify, callback, name);
+ notify, callback, name);
if (!vq) {
/* For now, we fail if we can't get the requested size. */
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 3ff746e3f24..dd4424c1423 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -285,6 +285,16 @@ static bool vm_notify(struct virtqueue *vq)
return true;
}
+static bool vm_notify_with_data(struct virtqueue *vq)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
+ u32 data = vring_notification_data(vq);
+
+ writel(data, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
+
+ return true;
+}
+
/* Notify all virtqueues on an interrupt. */
static irqreturn_t vm_interrupt(int irq, void *opaque)
{
@@ -363,12 +373,18 @@ static struct virtqueue *vm_setup_vq(struct virtio_device
*vdev, unsigned int in
const char *name, bool ctx)
{
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ bool (*notify)(struct virtqueue *vq);
struct virtio_mmio_vq_info *info;
struct virtqueue *vq;
unsigned long flags;
unsigned int num;
int err;
+ if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA))
+ notify = vm_notify_with_data;
+ else
+ notify = vm_notify;
+
if (!name)
return NULL;
@@ -397,7 +413,7 @@ static struct virtqueue *vm_setup_vq(struct virtio_device
*vdev, unsigned int in
/* Create the vring */
vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev,
- true, true, ctx, vm_notify, callback, name);
+ true, true, ctx, notify, callback, name);
if (!vq) {
err = -ENOMEM;
goto error_new_virtqueue;
diff --git a/drivers/virtio/virtio_pci_modern.c
b/drivers/virtio/virtio_pci_modern.c
index 9e496e288cf..05deba5153b 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -288,6 +288,15 @@ static u16 vp_config_vector(struct virtio_pci_device
*vp_dev, u16 vector)
return vp_modern_config_vector(&vp_dev->mdev, vector);
}
+static bool vp_notify_with_data(struct virtqueue *vq)
+{
+ u32 data = vring_notification_data(vq);
+
+ iowrite32(data, (void __iomem *)vq->priv);
+
+ return true;
+}
+
static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
struct virtio_pci_vq_info *info,
unsigned int index,
@@ -298,10 +307,16 @@ static struct virtqueue *setup_vq(struct virtio_pci_device
*vp_dev,
{
struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
+ bool (*notify)(struct virtqueue *vq);
struct virtqueue *vq;
u16 num;
int err;
+ if (__virtio_test_bit(&vp_dev->vdev, VIRTIO_F_NOTIFICATION_DATA))
+ notify = vp_notify_with_data;
+ else
+ notify = vp_notify;
+
if (index >= vp_modern_get_num_queues(mdev))
return ERR_PTR(-EINVAL);
@@ -321,7 +336,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device
*vp_dev,
vq = vring_create_virtqueue(index, num,
SMP_CACHE_BYTES, &vp_dev->vdev,
true, true, ctx,
- vp_notify, callback, name);
+ notify, callback, name);
if (!vq)
return ERR_PTR(-ENOMEM);
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 41144b5246a..7749bd5f99f 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -2752,6 +2752,23 @@ void vring_del_virtqueue(struct virtqueue *_vq)
}
EXPORT_SYMBOL_GPL(vring_del_virtqueue);
+u32 vring_notification_data(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+ u16 next;
+
+ if (vq->packed_ring)
+ next = (vq->packed.next_avail_idx &
+ ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR))) |
+ vq->packed.avail_wrap_counter <<
+ VRING_PACKED_EVENT_F_WRAP_CTR;
+ else
+ next = vq->split.avail_idx_shadow;
+
+ return next << 16 | _vq->index;
+}
+EXPORT_SYMBOL_GPL(vring_notification_data);
+
/* Manipulates transport-specific feature bits. */
void vring_transport_features(struct virtio_device *vdev)
{
@@ -2771,6 +2788,8 @@ void vring_transport_features(struct virtio_device *vdev)
break;
case VIRTIO_F_ORDER_PLATFORM:
break;
+ case VIRTIO_F_NOTIFICATION_DATA:
+ break;
default:
/* We don't understand this bit. */
__virtio_clear_bit(vdev, i);
diff --git a/include/linux/virtio_ring.h b/include/linux/virtio_ring.h
index 8b95b69ef69..2550c9170f4 100644
--- a/include/linux/virtio_ring.h
+++ b/include/linux/virtio_ring.h
@@ -117,4 +117,6 @@ void vring_del_virtqueue(struct virtqueue *vq);
void vring_transport_features(struct virtio_device *vdev);
irqreturn_t vring_interrupt(int irq, void *_vq);
+
+u32 vring_notification_data(struct virtqueue *_vq);
#endif /* _LINUX_VIRTIO_RING_H */
diff --git a/include/uapi/linux/virtio_config.h
b/include/uapi/linux/virtio_config.h
index 3c05162bc98..2c712c65416 100644
--- a/include/uapi/linux/virtio_config.h
+++ b/include/uapi/linux/virtio_config.h
@@ -99,6 +99,12 @@
*/
#define VIRTIO_F_SR_IOV 37
+/*
+ * This feature indicates that the driver passes extra data (besides
+ * identifying the virtqueue) in its device notifications.
+ */
+#define VIRTIO_F_NOTIFICATION_DATA 38
+
/*
* This feature indicates that the driver can reset a queue individually.
*/
--
2.34.1
Alvaro Karsz
2023-Apr-13 08:18 UTC
[PATCH 2/2] virtio-vdpa: add VIRTIO_F_NOTIFICATION_DATA feature support
Add VIRTIO_F_NOTIFICATION_DATA support for vDPA transport.
If this feature is negotiated, the driver passes extra data when kicking
a virtqueue.
A device that offers this feature needs to implement the
kick_vq_with_data callback.
kick_vq_with_data receives the vDPA device and data.
data includes:
16 bits vqn and 16 bits next available index for split virtqueues.
16 bits vqs, 15 least significant bits of next available index
and 1 bit next_wrap for packed virtqueues.
This patch follows a patch [1] by Viktor Prutyanov which adds support
for the MMIO, channel I/O and modern PCI transports.
Signed-off-by: Alvaro Karsz <alvaro.karsz at solid-run.com>
---
drivers/virtio/virtio_vdpa.c | 23 +++++++++++++++++++++--
include/linux/vdpa.h | 9 +++++++++
2 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index d7f5af62dda..737c1f36d32 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -112,6 +112,17 @@ static bool virtio_vdpa_notify(struct virtqueue *vq)
return true;
}
+static bool virtio_vdpa_notify_with_data(struct virtqueue *vq)
+{
+ struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev);
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u32 data = vring_notification_data(vq);
+
+ ops->kick_vq_with_data(vdpa, data);
+
+ return true;
+}
+
static irqreturn_t virtio_vdpa_config_cb(void *private)
{
struct virtio_vdpa_device *vd_dev = private;
@@ -138,6 +149,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned
int index,
struct device *dma_dev;
const struct vdpa_config_ops *ops = vdpa->config;
struct virtio_vdpa_vq_info *info;
+ bool (*notify)(struct virtqueue *vq) = virtio_vdpa_notify;
struct vdpa_callback cb;
struct virtqueue *vq;
u64 desc_addr, driver_addr, device_addr;
@@ -154,6 +166,14 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned
int index,
if (index >= vdpa->nvqs)
return ERR_PTR(-ENOENT);
+ /* We cannot accept VIRTIO_F_NOTIFICATION_DATA without kick_vq_with_data */
+ if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) {
+ if (ops->kick_vq_with_data)
+ notify = virtio_vdpa_notify_with_data;
+ else
+ __virtio_clear_bit(vdev, VIRTIO_F_NOTIFICATION_DATA);
+ }
+
/* Queue shouldn't already be set up. */
if (ops->get_vq_ready(vdpa, index))
return ERR_PTR(-ENOENT);
@@ -183,8 +203,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned
int index,
dma_dev = vdpa_get_dma_dev(vdpa);
vq = vring_create_virtqueue_dma(index, max_num, align, vdev,
true, may_reduce_num, ctx,
- virtio_vdpa_notify, callback,
- name, dma_dev);
+ notify, callback, name, dma_dev);
if (!vq) {
err = -ENOMEM;
goto error_new_virtqueue;
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 43f59ef10cc..04cdaad77dd 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -143,6 +143,14 @@ struct vdpa_map_file {
* @kick_vq: Kick the virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
+ * @kick_vq_with_data: Kick the virtqueue and supply extra data
+ * (only if VIRTIO_F_NOTIFICATION_DATA is negotiated)
+ * @vdev: vdpa device
+ * @data for split virtqueue:
+ * 16 bits vqn and 16 bits next available index.
+ * @data for packed virtqueue:
+ * 16 bits vqn, 15 least significant bits of
+ * next available index and 1 bit next_wrap.
* @set_vq_cb: Set the interrupt callback function for
* a virtqueue
* @vdev: vdpa device
@@ -300,6 +308,7 @@ struct vdpa_config_ops {
u64 device_area);
void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
+ void (*kick_vq_with_data)(struct vdpa_device *vdev, u32 data);
void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
struct vdpa_callback *cb);
void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
--
2.34.1