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Jason Wang

2020-Dec-04 04:03 UTC

[PATCH V2 19/19] vdpa: introduce virtio pci driver

This patch introduce a vDPA driver for virtio-pci device. It bridges
the virtio-pci control command to the vDPA bus. This will be used for
features prototyping and testing.

Note that get/restore virtqueue state is not supported which needs
extension on the virtio specification.

Signed-off-by: Jason Wang <jasowang at redhat.com>
---
 drivers/vdpa/Kconfig              |   6 +
 drivers/vdpa/Makefile             |   1 +
 drivers/vdpa/virtio_pci/Makefile  |   2 +
 drivers/vdpa/virtio_pci/vp_vdpa.c | 455 ++++++++++++++++++++++++++++++
 4 files changed, 464 insertions(+)
 create mode 100644 drivers/vdpa/virtio_pci/Makefile
 create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa.c

diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index 358f6048dd3c..18cad14f533e 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -48,4 +48,10 @@ config MLX5_VDPA_NET
 	  be executed by the hardware. It also supports a variety of stateless
 	  offloads depending on the actual device used and firmware version.
 
+config VP_VDPA
+	tristate "Virtio PCI bridge vDPA driver"
+	depends on PCI_MSI && VIRTIO_PCI_MODERN
+	help
+	  This kernel module that bridges virtio PCI device to vDPA bus.
+
 endif # VDPA
diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile
index d160e9b63a66..67fe7f3d6943 100644
--- a/drivers/vdpa/Makefile
+++ b/drivers/vdpa/Makefile
@@ -3,3 +3,4 @@ obj-$(CONFIG_VDPA) += vdpa.o
 obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
 obj-$(CONFIG_IFCVF)    += ifcvf/
 obj-$(CONFIG_MLX5_VDPA) += mlx5/
+obj-$(CONFIG_VP_VDPA)    += virtio_pci/
diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
new file mode 100644
index 000000000000..231088d3af7d
--- /dev/null
+++ b/drivers/vdpa/virtio_pci/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c
b/drivers/vdpa/virtio_pci/vp_vdpa.c
new file mode 100644
index 000000000000..fa0321e77fb3
--- /dev/null
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -0,0 +1,455 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vDPA bridge driver for modern virtio-pci device
+ *
+ * Copyright (c) 2020, Red Hat Inc. All rights reserved.
+ * Author: Jason Wang <jasowang at redhat.com>
+ *
+ * Based on virtio_pci_modern.c.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/vdpa.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_pci.h>
+#include <linux/virtio_pci_modern.h>
+
+#define VP_VDPA_QUEUE_MAX 256
+#define VP_VDPA_DRIVER_NAME "vp_vdpa"
+
+struct vp_vring {
+	void __iomem *notify;
+	char msix_name[256];
+	struct vdpa_callback cb;
+	int irq;
+};
+
+struct vp_vdpa {
+	struct vdpa_device vdpa;
+	struct virtio_pci_modern_device mdev;
+	struct vp_vring *vring;
+	struct vdpa_callback cb;
+	char msix_name[256];
+	int config_irq;
+	int queues;
+	int vectors;
+};
+
+static struct vp_vdpa *vdpa_to_vp(struct vdpa_device *vdpa)
+{
+	return container_of(vdpa, struct vp_vdpa, vdpa);
+}
+
+static struct virtio_pci_modern_device *vdpa_to_mdev(struct vdpa_device *vdpa)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+
+	return &vp_vdpa->mdev;
+}
+
+static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	return vp_modern_get_features(mdev);
+}
+
+static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	vp_modern_set_features(mdev, features);
+
+	return 0;
+}
+
+static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	return vp_modern_get_status(mdev);
+}
+
+static void vp_vdpa_free_irq(struct vp_vdpa *vp_vdpa)
+{
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	struct pci_dev *pdev = mdev->pci_dev;
+	int i;
+
+	for (i = 0; i < vp_vdpa->queues; i++) {
+		if (vp_vdpa->vring[i].irq != VIRTIO_MSI_NO_VECTOR) {
+			vp_modern_queue_vector(mdev, i, VIRTIO_MSI_NO_VECTOR);
+			devm_free_irq(&pdev->dev, vp_vdpa->vring[i].irq,
+				      &vp_vdpa->vring[i]);
+			vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
+		}
+	}
+
+	if (vp_vdpa->config_irq != VIRTIO_MSI_NO_VECTOR) {
+		vp_modern_config_vector(mdev, VIRTIO_MSI_NO_VECTOR);
+		devm_free_irq(&pdev->dev, vp_vdpa->config_irq, vp_vdpa);
+		vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
+	}
+
+	if (vp_vdpa->vectors) {
+		pci_free_irq_vectors(pdev);
+		vp_vdpa->vectors = 0;
+	}
+}
+
+static irqreturn_t vp_vdpa_vq_handler(int irq, void *arg)
+{
+	struct vp_vring *vring = arg;
+
+	if (vring->cb.callback)
+		return vring->cb.callback(vring->cb.private);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t vp_vdpa_config_handler(int irq, void *arg)
+{
+	struct vp_vdpa *vp_vdpa = arg;
+
+	if (vp_vdpa->cb.callback)
+		return vp_vdpa->cb.callback(vp_vdpa->cb.private);
+
+	return IRQ_HANDLED;
+}
+
+static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa)
+{
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	struct pci_dev *pdev = mdev->pci_dev;
+	int i, ret, irq;
+	int queues = vp_vdpa->queues;
+	int vectors = queues + 1;
+
+	ret = pci_alloc_irq_vectors(pdev, vectors, vectors, PCI_IRQ_MSIX);
+	if (ret != vectors) {
+		dev_err(&pdev->dev,
+			"vp_vdpa: fail to allocate irq vectors want %d but %d\n",
+			vectors, ret);
+		return ret;
+	}
+
+	vp_vdpa->vectors = vectors;
+
+	for (i = 0; i < queues; i++) {
+		snprintf(vp_vdpa->vring[i].msix_name, 256,
+			"vp-vdpa[%s]-%d\n", pci_name(pdev), i);
+		irq = pci_irq_vector(pdev, i);
+		ret = devm_request_irq(&pdev->dev, irq,
+				       vp_vdpa_vq_handler,
+				       0, vp_vdpa->vring[i].msix_name,
+				       &vp_vdpa->vring[i]);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"vp_vdpa: fail to request irq for vq %d\n", i);
+			goto err;
+		}
+		vp_modern_queue_vector(mdev, i, i);
+		vp_vdpa->vring[i].irq = irq;
+	}
+
+	snprintf(vp_vdpa->msix_name, 256, "vp-vdpa[%s]-config\n",
+		 pci_name(pdev));
+	irq = pci_irq_vector(pdev, queues);
+	ret = devm_request_irq(&pdev->dev, irq,	vp_vdpa_config_handler, 0,
+			       vp_vdpa->msix_name, vp_vdpa);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"vp_vdpa: fail to request irq for vq %d\n", i);
+			goto err;
+	}
+	vp_modern_config_vector(mdev, queues);
+	vp_vdpa->config_irq = irq;
+
+	return 0;
+err:
+	vp_vdpa_free_irq(vp_vdpa);
+	return ret;
+}
+
+static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	u8 s = vp_vdpa_get_status(vdpa);
+
+	if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
+	    !(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
+		vp_vdpa_request_irq(vp_vdpa);
+	}
+
+	vp_modern_set_status(mdev, status);
+
+	if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+	    (s & VIRTIO_CONFIG_S_DRIVER_OK))
+		vp_vdpa_free_irq(vp_vdpa);
+}
+
+static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
+{
+	return VP_VDPA_QUEUE_MAX;
+}
+
+static int vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
+				struct vdpa_vq_state *state)
+{
+	/* Note that this is not supported by virtio specification, so
+	 * we return -EOPNOTSUPP here. This means we can't support live
+	 * migration, vhost device start/stop.
+	 */
+	return -EOPNOTSUPP;
+}
+
+static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
+				const struct vdpa_vq_state *state)
+{
+	/* Note that this is not supported by virtio specification, so
+	 * we return -ENOPOTSUPP here. This means we can't support live
+	 * migration, vhost device start/stop.
+	 */
+	return -EOPNOTSUPP;
+}
+
+static void vp_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid,
+			      struct vdpa_callback *cb)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+
+	vp_vdpa->vring[qid].cb = *cb;
+}
+
+static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
+				 u16 qid, bool ready)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	vp_modern_set_queue_enable(mdev, qid, ready);
+}
+
+static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	return vp_modern_get_queue_enable(mdev, qid);
+}
+
+static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
+			       u32 num)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	vp_modern_set_queue_size(mdev, qid, num);
+}
+
+static int vp_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid,
+				  u64 desc_area, u64 driver_area,
+				  u64 device_area)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	vp_modern_queue_address(mdev, qid, desc_area,
+				driver_area, device_area);
+
+	return 0;
+}
+
+static void vp_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+
+	vp_iowrite16(qid, vp_vdpa->vring[qid].notify);
+}
+
+static u32 vp_vdpa_get_generation(struct vdpa_device *vdpa)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	return vp_modern_generation(mdev);
+}
+
+static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	return mdev->id.device;
+}
+
+static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
+{
+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
+
+	return mdev->id.vendor;
+}
+
+static u32 vp_vdpa_get_vq_align(struct vdpa_device *vdpa)
+{
+	return PAGE_SIZE;
+}
+
+static void vp_vdpa_get_config(struct vdpa_device *vdpa,
+			       unsigned int offset,
+			       void *buf, unsigned int len)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	u8 old, new;
+	u8 *p;
+	int i;
+
+	do {
+		old = vp_ioread8(&mdev->common->config_generation);
+		p = buf;
+		for (i = 0; i < len; i++)
+			*p++ = vp_ioread8(mdev->device + offset + i);
+
+		new = vp_ioread8(&mdev->common->config_generation);
+	} while (old != new);
+}
+
+static void vp_vdpa_set_config(struct vdpa_device *vdpa,
+			       unsigned int offset, const void *buf,
+			       unsigned int len)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	const u8 *p = buf;
+	int i;
+
+	for (i = 0; i < len; i++)
+		vp_iowrite8(*p++, mdev->device + offset + i);
+}
+
+static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa,
+				  struct vdpa_callback *cb)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+
+	vp_vdpa->cb = *cb;
+}
+
+static const struct vdpa_config_ops vp_vdpa_ops = {
+	.get_features	= vp_vdpa_get_features,
+	.set_features	= vp_vdpa_set_features,
+	.get_status	= vp_vdpa_get_status,
+	.set_status	= vp_vdpa_set_status,
+	.get_vq_num_max	= vp_vdpa_get_vq_num_max,
+	.get_vq_state	= vp_vdpa_get_vq_state,
+	.set_vq_state	= vp_vdpa_set_vq_state,
+	.set_vq_cb	= vp_vdpa_set_vq_cb,
+	.set_vq_ready	= vp_vdpa_set_vq_ready,
+	.get_vq_ready	= vp_vdpa_get_vq_ready,
+	.set_vq_num	= vp_vdpa_set_vq_num,
+	.set_vq_address	= vp_vdpa_set_vq_address,
+	.kick_vq	= vp_vdpa_kick_vq,
+	.get_generation	= vp_vdpa_get_generation,
+	.get_device_id	= vp_vdpa_get_device_id,
+	.get_vendor_id	= vp_vdpa_get_vendor_id,
+	.get_vq_align	= vp_vdpa_get_vq_align,
+	.get_config	= vp_vdpa_get_config,
+	.set_config	= vp_vdpa_set_config,
+	.set_config_cb  = vp_vdpa_set_config_cb,
+};
+
+static void vp_vdpa_free_irq_vectors(void *data)
+{
+	pci_free_irq_vectors(data);
+}
+
+static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct virtio_pci_modern_device *mdev;
+	struct device *dev = &pdev->dev;
+	struct vp_vdpa *vp_vdpa;
+	u16 notify_off;
+	int ret, i;
+
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return ret;
+
+	vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
+				    dev, &vp_vdpa_ops);
+	if (vp_vdpa == NULL) {
+		dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
+		return -ENOMEM;
+	}
+
+	mdev = &vp_vdpa->mdev;
+	mdev->pci_dev = pdev;
+
+	if (vp_modern_probe(mdev)) {
+		dev_err(&pdev->dev, "Failed to probe modern PCI device\n");
+		goto err;
+	}
+
+	pci_set_master(pdev);
+	pci_set_drvdata(pdev, vp_vdpa);
+
+	vp_vdpa->vdpa.dma_dev = &pdev->dev;
+	vp_vdpa->queues = vp_modern_get_num_queues(mdev);
+
+	ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed for adding devres for freeing irq vectors\n");
+		goto err;
+	}
+
+	vp_vdpa->vring = devm_kcalloc(&pdev->dev, vp_vdpa->queues,
+				      sizeof(*vp_vdpa->vring),
+				      GFP_KERNEL);
+	if (!vp_vdpa->vring) {
+		dev_err(&pdev->dev, "Fail to allocate virtqueues\n");
+		goto err;
+	}
+
+	for (i = 0; i < vp_vdpa->queues; i++) {
+		notify_off = vp_modern_get_queue_notify_off(mdev, i);
+		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
+		vp_vdpa->vring[i].notify = mdev->notify_base +
+			notify_off * mdev->notify_offset_multiplier;
+	}
+	vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
+
+	ret = vdpa_register_device(&vp_vdpa->vdpa, vp_vdpa->queues);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to register to vdpa bus\n");
+		goto err;
+	}
+
+	return 0;
+
+err:
+	put_device(&vp_vdpa->vdpa.dev);
+	return ret;
+}
+
+static void vp_vdpa_remove(struct pci_dev *pdev)
+{
+	struct vp_vdpa *vp_vdpa = pci_get_drvdata(pdev);
+
+	vdpa_unregister_device(&vp_vdpa->vdpa);
+	vp_modern_remove(&vp_vdpa->mdev);
+}
+
+static struct pci_driver vp_vdpa_driver = {
+	.name		= "vp-vdpa",
+	.id_table	= NULL, /* only dynamic ids */
+	.probe		= vp_vdpa_probe,
+	.remove		= vp_vdpa_remove,
+};
+
+module_pci_driver(vp_vdpa_driver);
+
+MODULE_AUTHOR("Jason Wang <jasowang at redhat.com>");
+MODULE_DESCRIPTION("vp-vdpa");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1");
-- 
2.25.1

Stefano Garzarella

2020-Dec-04 15:20 UTC

head link

[PATCH V2 19/19] vdpa: introduce virtio pci driver

On Fri, Dec 04, 2020 at 12:03:53PM +0800, Jason Wang
wrote:>This patch introduce a vDPA driver for virtio-pci device. It bridges
>the virtio-pci control command to the vDPA bus. This will be used for
>features prototyping and testing.
>
>Note that get/restore virtqueue state is not supported which needs
>extension on the virtio specification.
>
>Signed-off-by: Jason Wang <jasowang at redhat.com>
>---
> drivers/vdpa/Kconfig              |   6 +
> drivers/vdpa/Makefile             |   1 +
> drivers/vdpa/virtio_pci/Makefile  |   2 +
> drivers/vdpa/virtio_pci/vp_vdpa.c | 455 ++++++++++++++++++++++++++++++
> 4 files changed, 464 insertions(+)
> create mode 100644 drivers/vdpa/virtio_pci/Makefile
> create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa.c
>
>diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
>index 358f6048dd3c..18cad14f533e 100644
>--- a/drivers/vdpa/Kconfig
>+++ b/drivers/vdpa/Kconfig
>@@ -48,4 +48,10 @@ config MLX5_VDPA_NET
> 	  be executed by the hardware. It also supports a variety of stateless
> 	  offloads depending on the actual device used and firmware version.
>
>+config VP_VDPA
>+	tristate "Virtio PCI bridge vDPA driver"
>+	depends on PCI_MSI && VIRTIO_PCI_MODERN
>+	help
>+	  This kernel module that bridges virtio PCI device to vDPA bus.                              ^
Without 'that' maybe sound better, but I'm not a native speaker :-)
>+
> endif # VDPA
>diff --git a/drivers/vdpa/Makefile b/drivers/vdpa/Makefile
>index d160e9b63a66..67fe7f3d6943 100644
>--- a/drivers/vdpa/Makefile
>+++ b/drivers/vdpa/Makefile
>@@ -3,3 +3,4 @@ obj-$(CONFIG_VDPA) += vdpa.o
> obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
> obj-$(CONFIG_IFCVF)    += ifcvf/
> obj-$(CONFIG_MLX5_VDPA) += mlx5/
>+obj-$(CONFIG_VP_VDPA)    += virtio_pci/
>diff --git a/drivers/vdpa/virtio_pci/Makefile
b/drivers/vdpa/virtio_pci/Makefile
>new file mode 100644
>index 000000000000..231088d3af7d
>--- /dev/null
>+++ b/drivers/vdpa/virtio_pci/Makefile
>@@ -0,0 +1,2 @@
>+# SPDX-License-Identifier: GPL-2.0
>+obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
>diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c
b/drivers/vdpa/virtio_pci/vp_vdpa.c
>new file mode 100644
>index 000000000000..fa0321e77fb3
>--- /dev/null
>+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
>@@ -0,0 +1,455 @@
>+// SPDX-License-Identifier: GPL-2.0-only
>+/*
>+ * vDPA bridge driver for modern virtio-pci device
>+ *
>+ * Copyright (c) 2020, Red Hat Inc. All rights reserved.
>+ * Author: Jason Wang <jasowang at redhat.com>
>+ *
>+ * Based on virtio_pci_modern.c.
>+ */
>+
>+#include <linux/interrupt.h>
>+#include <linux/module.h>
>+#include <linux/pci.h>
>+#include <linux/vdpa.h>
>+#include <linux/virtio.h>
>+#include <linux/virtio_config.h>
>+#include <linux/virtio_ring.h>
>+#include <linux/virtio_pci.h>
>+#include <linux/virtio_pci_modern.h>
>+
>+#define VP_VDPA_QUEUE_MAX 256
>+#define VP_VDPA_DRIVER_NAME "vp_vdpa"
>+
>+struct vp_vring {
>+	void __iomem *notify;
>+	char msix_name[256];
Can we use a macro for the msix_name size, since we use 256 in multiple 
places?
>+	struct vdpa_callback cb;
>+	int irq;
>+};
>+
>+struct vp_vdpa {
>+	struct vdpa_device vdpa;
>+	struct virtio_pci_modern_device mdev;
>+	struct vp_vring *vring;
>+	struct vdpa_callback cb;                              ^
It is not relevant, but 'config_cb' is maybe clearer to read.

The rest looks good.

Thanks,
Stefano
>+	char msix_name[256];
>+	int config_irq;
>+	int queues;
>+	int vectors;
>+};
>+
>+static struct vp_vdpa *vdpa_to_vp(struct vdpa_device *vdpa)
>+{
>+	return container_of(vdpa, struct vp_vdpa, vdpa);
>+}
>+
>+static struct virtio_pci_modern_device *vdpa_to_mdev(struct vdpa_device
*vdpa)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+
>+	return &vp_vdpa->mdev;
>+}
>+
>+static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	return vp_modern_get_features(mdev);
>+}
>+
>+static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	vp_modern_set_features(mdev, features);
>+
>+	return 0;
>+}
>+
>+static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	return vp_modern_get_status(mdev);
>+}
>+
>+static void vp_vdpa_free_irq(struct vp_vdpa *vp_vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
>+	struct pci_dev *pdev = mdev->pci_dev;
>+	int i;
>+
>+	for (i = 0; i < vp_vdpa->queues; i++) {
>+		if (vp_vdpa->vring[i].irq != VIRTIO_MSI_NO_VECTOR) {
>+			vp_modern_queue_vector(mdev, i, VIRTIO_MSI_NO_VECTOR);
>+			devm_free_irq(&pdev->dev, vp_vdpa->vring[i].irq,
>+				      &vp_vdpa->vring[i]);
>+			vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
>+		}
>+	}
>+
>+	if (vp_vdpa->config_irq != VIRTIO_MSI_NO_VECTOR) {
>+		vp_modern_config_vector(mdev, VIRTIO_MSI_NO_VECTOR);
>+		devm_free_irq(&pdev->dev, vp_vdpa->config_irq, vp_vdpa);
>+		vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
>+	}
>+
>+	if (vp_vdpa->vectors) {
>+		pci_free_irq_vectors(pdev);
>+		vp_vdpa->vectors = 0;
>+	}
>+}
>+
>+static irqreturn_t vp_vdpa_vq_handler(int irq, void *arg)
>+{
>+	struct vp_vring *vring = arg;
>+
>+	if (vring->cb.callback)
>+		return vring->cb.callback(vring->cb.private);
>+
>+	return IRQ_HANDLED;
>+}
>+
>+static irqreturn_t vp_vdpa_config_handler(int irq, void *arg)
>+{
>+	struct vp_vdpa *vp_vdpa = arg;
>+
>+	if (vp_vdpa->cb.callback)
>+		return vp_vdpa->cb.callback(vp_vdpa->cb.private);
>+
>+	return IRQ_HANDLED;
>+}
>+
>+static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
>+	struct pci_dev *pdev = mdev->pci_dev;
>+	int i, ret, irq;
>+	int queues = vp_vdpa->queues;
>+	int vectors = queues + 1;
>+
>+	ret = pci_alloc_irq_vectors(pdev, vectors, vectors, PCI_IRQ_MSIX);
>+	if (ret != vectors) {
>+		dev_err(&pdev->dev,
>+			"vp_vdpa: fail to allocate irq vectors want %d but %d\n",
>+			vectors, ret);
>+		return ret;
>+	}
>+
>+	vp_vdpa->vectors = vectors;
>+
>+	for (i = 0; i < queues; i++) {
>+		snprintf(vp_vdpa->vring[i].msix_name, 256,
>+			"vp-vdpa[%s]-%d\n", pci_name(pdev), i);
>+		irq = pci_irq_vector(pdev, i);
>+		ret = devm_request_irq(&pdev->dev, irq,
>+				       vp_vdpa_vq_handler,
>+				       0, vp_vdpa->vring[i].msix_name,
>+				       &vp_vdpa->vring[i]);
>+		if (ret) {
>+			dev_err(&pdev->dev,
>+				"vp_vdpa: fail to request irq for vq %d\n", i);
>+			goto err;
>+		}
>+		vp_modern_queue_vector(mdev, i, i);
>+		vp_vdpa->vring[i].irq = irq;
>+	}
>+
>+	snprintf(vp_vdpa->msix_name, 256, "vp-vdpa[%s]-config\n",
>+		 pci_name(pdev));
>+	irq = pci_irq_vector(pdev, queues);
>+	ret = devm_request_irq(&pdev->dev, irq,	vp_vdpa_config_handler, 0,
>+			       vp_vdpa->msix_name, vp_vdpa);
>+	if (ret) {
>+		dev_err(&pdev->dev,
>+			"vp_vdpa: fail to request irq for vq %d\n", i);
>+			goto err;
>+	}
>+	vp_modern_config_vector(mdev, queues);
>+	vp_vdpa->config_irq = irq;
>+
>+	return 0;
>+err:
>+	vp_vdpa_free_irq(vp_vdpa);
>+	return ret;
>+}
>+
>+static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
>+	u8 s = vp_vdpa_get_status(vdpa);
>+
>+	if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
>+	    !(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
>+		vp_vdpa_request_irq(vp_vdpa);
>+	}
>+
>+	vp_modern_set_status(mdev, status);
>+
>+	if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
>+	    (s & VIRTIO_CONFIG_S_DRIVER_OK))
>+		vp_vdpa_free_irq(vp_vdpa);
>+}
>+
>+static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
>+{
>+	return VP_VDPA_QUEUE_MAX;
>+}
>+
>+static int vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
>+				struct vdpa_vq_state *state)
>+{
>+	/* Note that this is not supported by virtio specification, so
>+	 * we return -EOPNOTSUPP here. This means we can't support live
>+	 * migration, vhost device start/stop.
>+	 */
>+	return -EOPNOTSUPP;
>+}
>+
>+static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
>+				const struct vdpa_vq_state *state)
>+{
>+	/* Note that this is not supported by virtio specification, so
>+	 * we return -ENOPOTSUPP here. This means we can't support live
>+	 * migration, vhost device start/stop.
>+	 */
>+	return -EOPNOTSUPP;
>+}
>+
>+static void vp_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid,
>+			      struct vdpa_callback *cb)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+
>+	vp_vdpa->vring[qid].cb = *cb;
>+}
>+
>+static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
>+				 u16 qid, bool ready)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	vp_modern_set_queue_enable(mdev, qid, ready);
>+}
>+
>+static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	return vp_modern_get_queue_enable(mdev, qid);
>+}
>+
>+static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
>+			       u32 num)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	vp_modern_set_queue_size(mdev, qid, num);
>+}
>+
>+static int vp_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid,
>+				  u64 desc_area, u64 driver_area,
>+				  u64 device_area)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	vp_modern_queue_address(mdev, qid, desc_area,
>+				driver_area, device_area);
>+
>+	return 0;
>+}
>+
>+static void vp_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+
>+	vp_iowrite16(qid, vp_vdpa->vring[qid].notify);
>+}
>+
>+static u32 vp_vdpa_get_generation(struct vdpa_device *vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	return vp_modern_generation(mdev);
>+}
>+
>+static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	return mdev->id.device;
>+}
>+
>+static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
>+{
>+	struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
>+
>+	return mdev->id.vendor;
>+}
>+
>+static u32 vp_vdpa_get_vq_align(struct vdpa_device *vdpa)
>+{
>+	return PAGE_SIZE;
>+}
>+
>+static void vp_vdpa_get_config(struct vdpa_device *vdpa,
>+			       unsigned int offset,
>+			       void *buf, unsigned int len)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
>+	u8 old, new;
>+	u8 *p;
>+	int i;
>+
>+	do {
>+		old = vp_ioread8(&mdev->common->config_generation);
>+		p = buf;
>+		for (i = 0; i < len; i++)
>+			*p++ = vp_ioread8(mdev->device + offset + i);
>+
>+		new = vp_ioread8(&mdev->common->config_generation);
>+	} while (old != new);
>+}
>+
>+static void vp_vdpa_set_config(struct vdpa_device *vdpa,
>+			       unsigned int offset, const void *buf,
>+			       unsigned int len)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
>+	const u8 *p = buf;
>+	int i;
>+
>+	for (i = 0; i < len; i++)
>+		vp_iowrite8(*p++, mdev->device + offset + i);
>+}
>+
>+static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa,
>+				  struct vdpa_callback *cb)
>+{
>+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
>+
>+	vp_vdpa->cb = *cb;
>+}
>+
>+static const struct vdpa_config_ops vp_vdpa_ops = {
>+	.get_features	= vp_vdpa_get_features,
>+	.set_features	= vp_vdpa_set_features,
>+	.get_status	= vp_vdpa_get_status,
>+	.set_status	= vp_vdpa_set_status,
>+	.get_vq_num_max	= vp_vdpa_get_vq_num_max,
>+	.get_vq_state	= vp_vdpa_get_vq_state,
>+	.set_vq_state	= vp_vdpa_set_vq_state,
>+	.set_vq_cb	= vp_vdpa_set_vq_cb,
>+	.set_vq_ready	= vp_vdpa_set_vq_ready,
>+	.get_vq_ready	= vp_vdpa_get_vq_ready,
>+	.set_vq_num	= vp_vdpa_set_vq_num,
>+	.set_vq_address	= vp_vdpa_set_vq_address,
>+	.kick_vq	= vp_vdpa_kick_vq,
>+	.get_generation	= vp_vdpa_get_generation,
>+	.get_device_id	= vp_vdpa_get_device_id,
>+	.get_vendor_id	= vp_vdpa_get_vendor_id,
>+	.get_vq_align	= vp_vdpa_get_vq_align,
>+	.get_config	= vp_vdpa_get_config,
>+	.set_config	= vp_vdpa_set_config,
>+	.set_config_cb  = vp_vdpa_set_config_cb,
>+};
>+
>+static void vp_vdpa_free_irq_vectors(void *data)
>+{
>+	pci_free_irq_vectors(data);
>+}
>+
>+static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id 
>*id)
>+{
>+	struct virtio_pci_modern_device *mdev;
>+	struct device *dev = &pdev->dev;
>+	struct vp_vdpa *vp_vdpa;
>+	u16 notify_off;
>+	int ret, i;
>+
>+	ret = pcim_enable_device(pdev);
>+	if (ret)
>+		return ret;
>+
>+	vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
>+				    dev, &vp_vdpa_ops);
>+	if (vp_vdpa == NULL) {
>+		dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
>+		return -ENOMEM;
>+	}
>+
>+	mdev = &vp_vdpa->mdev;
>+	mdev->pci_dev = pdev;
>+
>+	if (vp_modern_probe(mdev)) {
>+		dev_err(&pdev->dev, "Failed to probe modern PCI
device\n");
>+		goto err;
>+	}
>+
>+	pci_set_master(pdev);
>+	pci_set_drvdata(pdev, vp_vdpa);
>+
>+	vp_vdpa->vdpa.dma_dev = &pdev->dev;
>+	vp_vdpa->queues = vp_modern_get_num_queues(mdev);
>+
>+	ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
>+	if (ret) {
>+		dev_err(&pdev->dev,
>+			"Failed for adding devres for freeing irq vectors\n");
>+		goto err;
>+	}
>+
>+	vp_vdpa->vring = devm_kcalloc(&pdev->dev, vp_vdpa->queues,
>+				      sizeof(*vp_vdpa->vring),
>+				      GFP_KERNEL);
>+	if (!vp_vdpa->vring) {
>+		dev_err(&pdev->dev, "Fail to allocate virtqueues\n");
>+		goto err;
>+	}
>+
>+	for (i = 0; i < vp_vdpa->queues; i++) {
>+		notify_off = vp_modern_get_queue_notify_off(mdev, i);
>+		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
>+		vp_vdpa->vring[i].notify = mdev->notify_base +
>+			notify_off * mdev->notify_offset_multiplier;
>+	}
>+	vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
>+
>+	ret = vdpa_register_device(&vp_vdpa->vdpa, vp_vdpa->queues);
>+	if (ret) {
>+		dev_err(&pdev->dev, "Failed to register to vdpa bus\n");
>+		goto err;
>+	}
>+
>+	return 0;
>+
>+err:
>+	put_device(&vp_vdpa->vdpa.dev);
>+	return ret;
>+}
>+
>+static void vp_vdpa_remove(struct pci_dev *pdev)
>+{
>+	struct vp_vdpa *vp_vdpa = pci_get_drvdata(pdev);
>+
>+	vdpa_unregister_device(&vp_vdpa->vdpa);
>+	vp_modern_remove(&vp_vdpa->mdev);
>+}
>+
>+static struct pci_driver vp_vdpa_driver = {
>+	.name		= "vp-vdpa",
>+	.id_table	= NULL, /* only dynamic ids */
>+	.probe		= vp_vdpa_probe,
>+	.remove		= vp_vdpa_remove,
>+};
>+
>+module_pci_driver(vp_vdpa_driver);
>+
>+MODULE_AUTHOR("Jason Wang <jasowang at redhat.com>");
>+MODULE_DESCRIPTION("vp-vdpa");
>+MODULE_LICENSE("GPL");
>+MODULE_VERSION("1");
>-- 
>2.25.1
>
>_______________________________________________
>Virtualization mailing list
>Virtualization at lists.linux-foundation.org
>https://lists.linuxfoundation.org/mailman/listinfo/virtualization
>

Jason Wang

2021-Jan-04 03:28 UTC

head link

[PATCH V2 19/19] vdpa: introduce virtio pci driver

On 2020/12/4 ??11:20, Stefano Garzarella wrote:>> +#define VP_VDPA_QUEUE_MAX 256
>> +#define VP_VDPA_DRIVER_NAME "vp_vdpa"
>> +
>> +struct vp_vring {
>> +??? void __iomem *notify;
>> +??? char msix_name[256];
>
> Can we use a macro for the msix_name size, since we use 256 in 
> multiple places?

Yes, will switch to use a macro.

>
>> +??? struct vdpa_callback cb;
>> +??? int irq;
>> +};
>> +
>> +struct vp_vdpa {
>> +??? struct vdpa_device vdpa;
>> +??? struct virtio_pci_modern_device mdev;
>> +??? struct vp_vring *vring;
>> +??? struct vdpa_callback cb;
> ???????????????????????????? ^
> It is not relevant, but 'config_cb' is maybe clearer to read.
>
Will change to config_cb.

> The rest looks good.

Thanks

>
> Thanks,
> Stefano

Linux Virtualization - Jan 2021 - [PATCH V2 19/19] vdpa: introduce virtio pci driver

[PATCH V2 19/19] vdpa: introduce virtio pci driver

[PATCH V2 19/19] vdpa: introduce virtio pci driver

[PATCH V2 19/19] vdpa: introduce virtio pci driver