This patch implements a vdpa driver for legacy virtio-pci device. And
this has been tested with the ENI(Elastic Network Interface) which is a
hardware virtio network device in Alibaba ECS baremetal instance.
Note that legacy device doesn't support to change the virtqueue size, so
users should use get_vq_num_unchangeable callback to check if the
virqueue size can be changed. If not, users should get the virqueue size
first by the get_vq_num_max callback first then allocate same size
memory for the virtqueue otherwise the device won't work correctly.
Signed-off-by: Wu Zongyong <[email protected]>
---
drivers/vdpa/Kconfig | 7 +
drivers/vdpa/virtio_pci/Makefile | 1 +
drivers/vdpa/virtio_pci/vp_vdpa_common.c | 5 +
drivers/vdpa/virtio_pci/vp_vdpa_common.h | 11 +
drivers/vdpa/virtio_pci/vp_vdpa_legacy.c | 346 +++++++++++++++++++++++
5 files changed, 370 insertions(+)
create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
index a503c1b2bfd9..ccb4fdb11f0f 100644
--- a/drivers/vdpa/Kconfig
+++ b/drivers/vdpa/Kconfig
@@ -67,4 +67,11 @@ config VP_VDPA
help
This kernel module bridges virtio PCI device to vDPA bus.
+config VP_VDPA_LEGACY
+ bool "Support legacy virtio pci device"
+ depends on VP_VDPA
+ select VIRTIO_PCI_LIB_LEGACY
+ help
+ This option enables bridges legacy virito PCI device to vDPA bus.
+
endif # VDPA
diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
index a772d86952b1..77c52dfb8b56 100644
--- a/drivers/vdpa/virtio_pci/Makefile
+++ b/drivers/vdpa/virtio_pci/Makefile
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
vp_vdpa-y += vp_vdpa_common.o vp_vdpa_modern.o
+vp_vdpa-$(CONFIG_VP_VDPA_LEGACY) += vp_vdpa_legacy.o
obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.c b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
index 3ff24c9ad6e4..fa91dc153244 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa_common.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
@@ -8,6 +8,7 @@
* Based on virtio_pci_modern.c.
*/
+#include "linux/err.h"
#include <linux/irqreturn.h>
#include <linux/interrupt.h>
#include "vp_vdpa_common.h"
@@ -172,6 +173,10 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
return ret;
vp_vdpa = vp_vdpa_modern_probe(pdev);
+ if (PTR_ERR(vp_vdpa) == -ENODEV) {
+ dev_info(&pdev->dev, "Tring legacy driver");
+ vp_vdpa = vp_vdpa_legacy_probe(pdev);
+ }
if (IS_ERR(vp_vdpa))
return PTR_ERR(vp_vdpa);
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.h b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
index 57886b55a2e9..39f241d8321b 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa_common.h
+++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
@@ -10,6 +10,7 @@
#include <linux/virtio_ring.h>
#include <linux/virtio_pci.h>
#include <linux/virtio_pci_modern.h>
+#include <linux/virtio_pci_legacy.h>
#define VP_VDPA_DRIVER_NAME "vp_vdpa"
#define VP_VDPA_NAME_SIZE 256
@@ -26,6 +27,7 @@ struct vp_vdpa {
struct vdpa_device vdpa;
struct pci_dev *pci_dev;
struct virtio_pci_modern_device mdev;
+ struct virtio_pci_legacy_device ldev;
struct vp_vring *vring;
struct vdpa_callback config_cb;
char msix_name[VP_VDPA_NAME_SIZE];
@@ -53,4 +55,13 @@ void vp_vdpa_free_irq_vectors(void *data);
struct vp_vdpa *vp_vdpa_modern_probe(struct pci_dev *pdev);
+#if IS_ENABLED(CONFIG_VP_VDPA_LEGACY)
+struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev);
+#else
+static inline struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
+{
+ return ERR_PTR(-ENODEV);
+}
+#endif
+
#endif
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
new file mode 100644
index 000000000000..75a6879a27ca
--- /dev/null
+++ b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vDPA bridge driver for legacy virtio-pci device
+ *
+ * Copyright (c) 2021, Alibaba Inc. All rights reserved.
+ * Author: Wu Zongyong <[email protected]>
+ */
+
+#include "linux/pci.h"
+#include "linux/virtio_byteorder.h"
+#include "linux/virtio_pci_legacy.h"
+#include <uapi/linux/virtio_net.h>
+#include <uapi/linux/virtio_blk.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_pci.h>
+#include "vp_vdpa_common.h"
+
+static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
+{
+ struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+
+ return &vp_vdpa->ldev;
+}
+
+static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_features(ldev);
+}
+
+static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ vp_legacy_set_features(ldev, features);
+
+ return 0;
+}
+
+static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_status(ldev);
+}
+
+static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
+ const struct vdpa_vq_state *state)
+{
+ const struct vdpa_vq_state_split *split = &state->split;
+
+ if (split->avail_index == 0)
+ return 0;
+
+ return -EOPNOTSUPP;
+}
+
+static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
+ const struct vdpa_vq_state *state)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ /* Note that this is not supported by virtio specification.
+ * But if the state is by chance equal to the device initial
+ * state, we can let it go.
+ */
+ if (!vp_legacy_get_queue_enable(ldev, qid))
+ return vp_vdpa_set_vq_state_split(vdpa, state);
+
+ return -EOPNOTSUPP;
+}
+
+static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
+ u16 qid, bool ready)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ /* Legacy devices can only be activated by setting vq address,
+ * and queue_enable is not supported by specification. So for
+ * legacy devices, we use @vp_vdpa_set_vq_address to set vq
+ * ready instead.
+ */
+ if (!ready)
+ vp_legacy_set_queue_address(ldev, qid, 0);
+}
+
+static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return vp_legacy_get_queue_enable(ldev, qid);
+}
+
+/* Legacy devices don't support set vq num by specification,
+ * just report an error if someone try to set it.
+ */
+static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
+ u32 num)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ dev_err(&ldev->pci_dev->dev, "legacy device don't support set vq num\n");
+}
+
+static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ /* assume all virtqueues have the same size */
+ return vp_legacy_get_queue_size(ldev, 0);
+}
+
+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_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ vp_legacy_set_queue_address(ldev, qid, desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
+
+ return 0;
+}
+
+static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return ldev->id.device;
+}
+
+static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+
+ return ldev->id.vendor;
+}
+
+static size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
+ size_t size;
+
+ switch (ldev->id.device) {
+ case VIRTIO_ID_NET:
+ size = sizeof(struct virtio_net_config);
+ break;
+ case VIRTIO_ID_BLOCK:
+ size = sizeof(struct virtio_blk_config);
+ break;
+ default:
+ size = 0;
+ dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
+ }
+
+ return 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_legacy_device *ldev = &vp_vdpa->ldev;
+ void __iomem *ioaddr = ldev->ioaddr +
+ VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
+ offset;
+ u8 *p = buf;
+ int i;
+
+ /* legacy devices don't have a configuration generation field,
+ * so we just read it once.
+ */
+ for (i = 0; i < len; i++)
+ *p++ = ioread8(ioaddr + i);
+}
+
+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_legacy_device *ldev = &vp_vdpa->ldev;
+ void __iomem *ioaddr = ldev->ioaddr +
+ VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
+ offset;
+ const u8 *p = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ iowrite8(*p++, ioaddr + i);
+}
+
+static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
+{
+ struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+ struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
+ 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_legacy_set_status(ldev, status);
+
+ if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
+ (s & VIRTIO_CONFIG_S_DRIVER_OK)) {
+ vp_vdpa_free_irq(vp_vdpa);
+ }
+}
+
+static bool vp_vdpa_get_vq_num_unchangeable(struct vdpa_device *vdpa)
+{
+ return true;
+}
+
+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_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_size = vp_vdpa_get_config_size,
+ .get_config = vp_vdpa_get_config,
+ .set_config = vp_vdpa_set_config,
+ .set_config_cb = vp_vdpa_set_config_cb,
+ .get_vq_irq = vp_vdpa_get_vq_irq,
+ .get_vq_num_unchangeable = vp_vdpa_get_vq_num_unchangeable,
+};
+
+static u16 vp_vdpa_get_num_queues(struct vp_vdpa *vp_vdpa)
+{
+ struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
+ u32 features = vp_legacy_get_features(ldev);
+ u16 num;
+
+ switch (ldev->id.device) {
+ case VIRTIO_ID_NET:
+ num = 2;
+ if (features & VIRTIO_NET_F_MQ) {
+ __virtio16 max_virtqueue_pairs;
+
+ vp_vdpa_get_config(&vp_vdpa->vdpa,
+ offsetof(struct virtio_net_config, max_virtqueue_pairs),
+ &max_virtqueue_pairs,
+ sizeof(max_virtqueue_pairs));
+ num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
+ max_virtqueue_pairs);
+ }
+
+ if (features & VIRTIO_NET_F_CTRL_VQ)
+ num += 1;
+ break;
+ case VIRTIO_ID_BLOCK:
+ num = 1;
+ break;
+ default:
+ num = 0;
+ dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
+ }
+
+ return num;
+}
+
+static u16 vp_vdpa_queue_vector(struct vp_vdpa *vp_vdpa, u16 idx, u16 vector)
+{
+ return vp_legacy_queue_vector(&vp_vdpa->ldev, idx, vector);
+}
+
+static u16 vp_vdpa_config_vector(struct vp_vdpa *vp_vdpa, u16 vector)
+{
+ return vp_legacy_config_vector(&vp_vdpa->ldev, vector);
+}
+
+struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct vp_vdpa *vp_vdpa;
+ struct virtio_pci_legacy_device *ldev;
+ int ret, i;
+
+ vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, dev, &vp_vdpa_ops, NULL);
+ if (vp_vdpa == NULL) {
+ dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ ldev = &vp_vdpa->ldev;
+ ldev->pci_dev = pdev;
+
+ ret = vp_legacy_probe(ldev);
+ if (ret) {
+ dev_err(dev, "Failed to probe legacy 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_vdpa_get_num_queues(vp_vdpa);
+
+ ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
+ if (ret) {
+ dev_err(dev,
+ "Failed for adding devres for freeing irq vectors\n");
+ goto err;
+ }
+
+ vp_vdpa->vring = devm_kcalloc(dev, vp_vdpa->queues,
+ sizeof(*vp_vdpa->vring),
+ GFP_KERNEL);
+ if (!vp_vdpa->vring) {
+ ret = -ENOMEM;
+ dev_err(dev, "Fail to allocate virtqueues\n");
+ goto err;
+ }
+
+ for (i = 0; i < vp_vdpa->queues; i++) {
+ vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
+ vp_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
+ vp_vdpa->vring[i].notify_pa = pci_resource_start(pdev, 0) + VIRTIO_PCI_QUEUE_NOTIFY;
+ }
+ vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
+
+ vp_vdpa->queue_vector = vp_vdpa_queue_vector;
+ vp_vdpa->config_vector = vp_vdpa_config_vector;
+
+ return vp_vdpa;
+
+err:
+ put_device(&vp_vdpa->vdpa.dev);
+ return ERR_PTR(ret);
+}
--
2.31.1
On Wed, Sep 08, 2021 at 08:20:37PM +0800, Wu Zongyong wrote:
> This patch implements a vdpa driver for legacy virtio-pci device. And
> this has been tested with the ENI(Elastic Network Interface) which is a
> hardware virtio network device in Alibaba ECS baremetal instance.
>
> Note that legacy device doesn't support to change the virtqueue size, so
> users should use get_vq_num_unchangeable callback to check if the
> virqueue size can be changed.
Hmm isn't this implicit in this being a legacy device?
> If not, users should get the virqueue size
> first by the get_vq_num_max callback first then allocate same size
> memory for the virtqueue otherwise the device won't work correctly.
>
> Signed-off-by: Wu Zongyong <[email protected]>
> ---
> drivers/vdpa/Kconfig | 7 +
> drivers/vdpa/virtio_pci/Makefile | 1 +
> drivers/vdpa/virtio_pci/vp_vdpa_common.c | 5 +
> drivers/vdpa/virtio_pci/vp_vdpa_common.h | 11 +
> drivers/vdpa/virtio_pci/vp_vdpa_legacy.c | 346 +++++++++++++++++++++++
> 5 files changed, 370 insertions(+)
> create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
>
> diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
> index a503c1b2bfd9..ccb4fdb11f0f 100644
> --- a/drivers/vdpa/Kconfig
> +++ b/drivers/vdpa/Kconfig
> @@ -67,4 +67,11 @@ config VP_VDPA
> help
> This kernel module bridges virtio PCI device to vDPA bus.
>
> +config VP_VDPA_LEGACY
> + bool "Support legacy virtio pci device"
> + depends on VP_VDPA
> + select VIRTIO_PCI_LIB_LEGACY
> + help
> + This option enables bridges legacy virito PCI device to vDPA bus.
> +
> endif # VDPA
> diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
> index a772d86952b1..77c52dfb8b56 100644
> --- a/drivers/vdpa/virtio_pci/Makefile
> +++ b/drivers/vdpa/virtio_pci/Makefile
> @@ -1,4 +1,5 @@
> # SPDX-License-Identifier: GPL-2.0
>
> vp_vdpa-y += vp_vdpa_common.o vp_vdpa_modern.o
> +vp_vdpa-$(CONFIG_VP_VDPA_LEGACY) += vp_vdpa_legacy.o
> obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.c b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> index 3ff24c9ad6e4..fa91dc153244 100644
> --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> @@ -8,6 +8,7 @@
> * Based on virtio_pci_modern.c.
> */
>
> +#include "linux/err.h"
> #include <linux/irqreturn.h>
> #include <linux/interrupt.h>
> #include "vp_vdpa_common.h"
> @@ -172,6 +173,10 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> return ret;
>
> vp_vdpa = vp_vdpa_modern_probe(pdev);
> + if (PTR_ERR(vp_vdpa) == -ENODEV) {
> + dev_info(&pdev->dev, "Tring legacy driver");
> + vp_vdpa = vp_vdpa_legacy_probe(pdev);
> + }
> if (IS_ERR(vp_vdpa))
> return PTR_ERR(vp_vdpa);
>
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.h b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> index 57886b55a2e9..39f241d8321b 100644
> --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> @@ -10,6 +10,7 @@
> #include <linux/virtio_ring.h>
> #include <linux/virtio_pci.h>
> #include <linux/virtio_pci_modern.h>
> +#include <linux/virtio_pci_legacy.h>
>
> #define VP_VDPA_DRIVER_NAME "vp_vdpa"
> #define VP_VDPA_NAME_SIZE 256
> @@ -26,6 +27,7 @@ struct vp_vdpa {
> struct vdpa_device vdpa;
> struct pci_dev *pci_dev;
> struct virtio_pci_modern_device mdev;
> + struct virtio_pci_legacy_device ldev;
> struct vp_vring *vring;
> struct vdpa_callback config_cb;
> char msix_name[VP_VDPA_NAME_SIZE];
> @@ -53,4 +55,13 @@ void vp_vdpa_free_irq_vectors(void *data);
>
> struct vp_vdpa *vp_vdpa_modern_probe(struct pci_dev *pdev);
>
> +#if IS_ENABLED(CONFIG_VP_VDPA_LEGACY)
> +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev);
> +#else
> +static inline struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> +{
> + return ERR_PTR(-ENODEV);
> +}
> +#endif
> +
> #endif
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> new file mode 100644
> index 000000000000..75a6879a27ca
> --- /dev/null
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> @@ -0,0 +1,346 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * vDPA bridge driver for legacy virtio-pci device
> + *
> + * Copyright (c) 2021, Alibaba Inc. All rights reserved.
> + * Author: Wu Zongyong <[email protected]>
> + */
> +
> +#include "linux/pci.h"
> +#include "linux/virtio_byteorder.h"
> +#include "linux/virtio_pci_legacy.h"
> +#include <uapi/linux/virtio_net.h>
> +#include <uapi/linux/virtio_blk.h>
> +#include <linux/virtio_ids.h>
> +#include <linux/virtio_pci.h>
> +#include "vp_vdpa_common.h"
> +
> +static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
> +{
> + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> +
> + return &vp_vdpa->ldev;
> +}
> +
> +static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + return vp_legacy_get_features(ldev);
> +}
> +
> +static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + vp_legacy_set_features(ldev, features);
> +
> + return 0;
> +}
> +
> +static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + return vp_legacy_get_status(ldev);
> +}
> +
> +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
> + const struct vdpa_vq_state *state)
> +{
> + const struct vdpa_vq_state_split *split = &state->split;
> +
> + if (split->avail_index == 0)
> + return 0;
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
> + const struct vdpa_vq_state *state)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + /* Note that this is not supported by virtio specification.
> + * But if the state is by chance equal to the device initial
> + * state, we can let it go.
> + */
> + if (!vp_legacy_get_queue_enable(ldev, qid))
> + return vp_vdpa_set_vq_state_split(vdpa, state);
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
> + u16 qid, bool ready)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + /* Legacy devices can only be activated by setting vq address,
> + * and queue_enable is not supported by specification. So for
> + * legacy devices, we use @vp_vdpa_set_vq_address to set vq
> + * ready instead.
> + */
> + if (!ready)
> + vp_legacy_set_queue_address(ldev, qid, 0);
> +}
> +
> +static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + return vp_legacy_get_queue_enable(ldev, qid);
> +}
> +
> +/* Legacy devices don't support set vq num by specification,
> + * just report an error if someone try to set it.
> + */
> +static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
> + u32 num)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + dev_err(&ldev->pci_dev->dev, "legacy device don't support set vq num\n");
> +}
> +
> +static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + /* assume all virtqueues have the same size */
> + return vp_legacy_get_queue_size(ldev, 0);
> +}
> +
> +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_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + vp_legacy_set_queue_address(ldev, qid, desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
> +
> + return 0;
> +}
> +
> +static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + return ldev->id.device;
> +}
> +
> +static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> +
> + return ldev->id.vendor;
> +}
> +
> +static size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> + size_t size;
> +
> + switch (ldev->id.device) {
> + case VIRTIO_ID_NET:
> + size = sizeof(struct virtio_net_config);
> + break;
> + case VIRTIO_ID_BLOCK:
> + size = sizeof(struct virtio_blk_config);
> + break;
> + default:
> + size = 0;
> + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> + }
> +
> + return 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_legacy_device *ldev = &vp_vdpa->ldev;
> + void __iomem *ioaddr = ldev->ioaddr +
> + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> + offset;
> + u8 *p = buf;
> + int i;
> +
> + /* legacy devices don't have a configuration generation field,
> + * so we just read it once.
> + */
> + for (i = 0; i < len; i++)
> + *p++ = ioread8(ioaddr + i);
> +}
> +
> +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_legacy_device *ldev = &vp_vdpa->ldev;
> + void __iomem *ioaddr = ldev->ioaddr +
> + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> + offset;
> + const u8 *p = buf;
> + int i;
> +
> + for (i = 0; i < len; i++)
> + iowrite8(*p++, ioaddr + i);
> +}
> +
> +static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
> +{
> + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> + 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_legacy_set_status(ldev, status);
> +
> + if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> + (s & VIRTIO_CONFIG_S_DRIVER_OK)) {
> + vp_vdpa_free_irq(vp_vdpa);
> + }
> +}
> +
> +static bool vp_vdpa_get_vq_num_unchangeable(struct vdpa_device *vdpa)
> +{
> + return true;
> +}
> +
> +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_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_size = vp_vdpa_get_config_size,
> + .get_config = vp_vdpa_get_config,
> + .set_config = vp_vdpa_set_config,
> + .set_config_cb = vp_vdpa_set_config_cb,
> + .get_vq_irq = vp_vdpa_get_vq_irq,
> + .get_vq_num_unchangeable = vp_vdpa_get_vq_num_unchangeable,
> +};
> +
> +static u16 vp_vdpa_get_num_queues(struct vp_vdpa *vp_vdpa)
> +{
> + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> + u32 features = vp_legacy_get_features(ldev);
> + u16 num;
> +
> + switch (ldev->id.device) {
> + case VIRTIO_ID_NET:
> + num = 2;
> + if (features & VIRTIO_NET_F_MQ) {
> + __virtio16 max_virtqueue_pairs;
> +
> + vp_vdpa_get_config(&vp_vdpa->vdpa,
> + offsetof(struct virtio_net_config, max_virtqueue_pairs),
> + &max_virtqueue_pairs,
> + sizeof(max_virtqueue_pairs));
> + num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
> + max_virtqueue_pairs);
> + }
> +
> + if (features & VIRTIO_NET_F_CTRL_VQ)
> + num += 1;
> + break;
> + case VIRTIO_ID_BLOCK:
> + num = 1;
> + break;
> + default:
> + num = 0;
> + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> + }
> +
> + return num;
> +}
> +
> +static u16 vp_vdpa_queue_vector(struct vp_vdpa *vp_vdpa, u16 idx, u16 vector)
> +{
> + return vp_legacy_queue_vector(&vp_vdpa->ldev, idx, vector);
> +}
> +
> +static u16 vp_vdpa_config_vector(struct vp_vdpa *vp_vdpa, u16 vector)
> +{
> + return vp_legacy_config_vector(&vp_vdpa->ldev, vector);
> +}
> +
> +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct vp_vdpa *vp_vdpa;
> + struct virtio_pci_legacy_device *ldev;
> + int ret, i;
> +
> + vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, dev, &vp_vdpa_ops, NULL);
> + if (vp_vdpa == NULL) {
> + dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + ldev = &vp_vdpa->ldev;
> + ldev->pci_dev = pdev;
> +
> + ret = vp_legacy_probe(ldev);
> + if (ret) {
> + dev_err(dev, "Failed to probe legacy 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_vdpa_get_num_queues(vp_vdpa);
> +
> + ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
> + if (ret) {
> + dev_err(dev,
> + "Failed for adding devres for freeing irq vectors\n");
> + goto err;
> + }
> +
> + vp_vdpa->vring = devm_kcalloc(dev, vp_vdpa->queues,
> + sizeof(*vp_vdpa->vring),
> + GFP_KERNEL);
> + if (!vp_vdpa->vring) {
> + ret = -ENOMEM;
> + dev_err(dev, "Fail to allocate virtqueues\n");
> + goto err;
> + }
> +
> + for (i = 0; i < vp_vdpa->queues; i++) {
> + vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
> + vp_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
> + vp_vdpa->vring[i].notify_pa = pci_resource_start(pdev, 0) + VIRTIO_PCI_QUEUE_NOTIFY;
> + }
> + vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
> +
> + vp_vdpa->queue_vector = vp_vdpa_queue_vector;
> + vp_vdpa->config_vector = vp_vdpa_config_vector;
> +
> + return vp_vdpa;
> +
> +err:
> + put_device(&vp_vdpa->vdpa.dev);
> + return ERR_PTR(ret);
> +}
> --
> 2.31.1
On Thu, Sep 09, 2021 at 09:57:50AM -0400, Michael S. Tsirkin wrote:
> On Wed, Sep 08, 2021 at 08:20:37PM +0800, Wu Zongyong wrote:
> > This patch implements a vdpa driver for legacy virtio-pci device. And
> > this has been tested with the ENI(Elastic Network Interface) which is a
> > hardware virtio network device in Alibaba ECS baremetal instance.
> >
> > Note that legacy device doesn't support to change the virtqueue size, so
> > users should use get_vq_num_unchangeable callback to check if the
> > virqueue size can be changed.
>
> Hmm isn't this implicit in this being a legacy device?
>
Yes, but there is no way to report the backend device is legacy for
users. So I add a new callback get_vq_num_unchangeable to indicate it.
> > If not, users should get the virqueue size
> > first by the get_vq_num_max callback first then allocate same size
> > memory for the virtqueue otherwise the device won't work correctly.
> >
> > Signed-off-by: Wu Zongyong <[email protected]>
> > ---
> > drivers/vdpa/Kconfig | 7 +
> > drivers/vdpa/virtio_pci/Makefile | 1 +
> > drivers/vdpa/virtio_pci/vp_vdpa_common.c | 5 +
> > drivers/vdpa/virtio_pci/vp_vdpa_common.h | 11 +
> > drivers/vdpa/virtio_pci/vp_vdpa_legacy.c | 346 +++++++++++++++++++++++
> > 5 files changed, 370 insertions(+)
> > create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> >
> > diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
> > index a503c1b2bfd9..ccb4fdb11f0f 100644
> > --- a/drivers/vdpa/Kconfig
> > +++ b/drivers/vdpa/Kconfig
> > @@ -67,4 +67,11 @@ config VP_VDPA
> > help
> > This kernel module bridges virtio PCI device to vDPA bus.
> >
> > +config VP_VDPA_LEGACY
> > + bool "Support legacy virtio pci device"
> > + depends on VP_VDPA
> > + select VIRTIO_PCI_LIB_LEGACY
> > + help
> > + This option enables bridges legacy virito PCI device to vDPA bus.
> > +
> > endif # VDPA
> > diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
> > index a772d86952b1..77c52dfb8b56 100644
> > --- a/drivers/vdpa/virtio_pci/Makefile
> > +++ b/drivers/vdpa/virtio_pci/Makefile
> > @@ -1,4 +1,5 @@
> > # SPDX-License-Identifier: GPL-2.0
> >
> > vp_vdpa-y += vp_vdpa_common.o vp_vdpa_modern.o
> > +vp_vdpa-$(CONFIG_VP_VDPA_LEGACY) += vp_vdpa_legacy.o
> > obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
> > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.c b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > index 3ff24c9ad6e4..fa91dc153244 100644
> > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > @@ -8,6 +8,7 @@
> > * Based on virtio_pci_modern.c.
> > */
> >
> > +#include "linux/err.h"
> > #include <linux/irqreturn.h>
> > #include <linux/interrupt.h>
> > #include "vp_vdpa_common.h"
> > @@ -172,6 +173,10 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> > return ret;
> >
> > vp_vdpa = vp_vdpa_modern_probe(pdev);
> > + if (PTR_ERR(vp_vdpa) == -ENODEV) {
> > + dev_info(&pdev->dev, "Tring legacy driver");
> > + vp_vdpa = vp_vdpa_legacy_probe(pdev);
> > + }
> > if (IS_ERR(vp_vdpa))
> > return PTR_ERR(vp_vdpa);
> >
> > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.h b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > index 57886b55a2e9..39f241d8321b 100644
> > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > @@ -10,6 +10,7 @@
> > #include <linux/virtio_ring.h>
> > #include <linux/virtio_pci.h>
> > #include <linux/virtio_pci_modern.h>
> > +#include <linux/virtio_pci_legacy.h>
> >
> > #define VP_VDPA_DRIVER_NAME "vp_vdpa"
> > #define VP_VDPA_NAME_SIZE 256
> > @@ -26,6 +27,7 @@ struct vp_vdpa {
> > struct vdpa_device vdpa;
> > struct pci_dev *pci_dev;
> > struct virtio_pci_modern_device mdev;
> > + struct virtio_pci_legacy_device ldev;
> > struct vp_vring *vring;
> > struct vdpa_callback config_cb;
> > char msix_name[VP_VDPA_NAME_SIZE];
> > @@ -53,4 +55,13 @@ void vp_vdpa_free_irq_vectors(void *data);
> >
> > struct vp_vdpa *vp_vdpa_modern_probe(struct pci_dev *pdev);
> >
> > +#if IS_ENABLED(CONFIG_VP_VDPA_LEGACY)
> > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev);
> > +#else
> > +static inline struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > +{
> > + return ERR_PTR(-ENODEV);
> > +}
> > +#endif
> > +
> > #endif
> > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > new file mode 100644
> > index 000000000000..75a6879a27ca
> > --- /dev/null
> > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > @@ -0,0 +1,346 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * vDPA bridge driver for legacy virtio-pci device
> > + *
> > + * Copyright (c) 2021, Alibaba Inc. All rights reserved.
> > + * Author: Wu Zongyong <[email protected]>
> > + */
> > +
> > +#include "linux/pci.h"
> > +#include "linux/virtio_byteorder.h"
> > +#include "linux/virtio_pci_legacy.h"
> > +#include <uapi/linux/virtio_net.h>
> > +#include <uapi/linux/virtio_blk.h>
> > +#include <linux/virtio_ids.h>
> > +#include <linux/virtio_pci.h>
> > +#include "vp_vdpa_common.h"
> > +
> > +static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
> > +{
> > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > +
> > + return &vp_vdpa->ldev;
> > +}
> > +
> > +static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + return vp_legacy_get_features(ldev);
> > +}
> > +
> > +static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + vp_legacy_set_features(ldev, features);
> > +
> > + return 0;
> > +}
> > +
> > +static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + return vp_legacy_get_status(ldev);
> > +}
> > +
> > +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
> > + const struct vdpa_vq_state *state)
> > +{
> > + const struct vdpa_vq_state_split *split = &state->split;
> > +
> > + if (split->avail_index == 0)
> > + return 0;
> > +
> > + return -EOPNOTSUPP;
> > +}
> > +
> > +static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
> > + const struct vdpa_vq_state *state)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + /* Note that this is not supported by virtio specification.
> > + * But if the state is by chance equal to the device initial
> > + * state, we can let it go.
> > + */
> > + if (!vp_legacy_get_queue_enable(ldev, qid))
> > + return vp_vdpa_set_vq_state_split(vdpa, state);
> > +
> > + return -EOPNOTSUPP;
> > +}
> > +
> > +static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
> > + u16 qid, bool ready)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + /* Legacy devices can only be activated by setting vq address,
> > + * and queue_enable is not supported by specification. So for
> > + * legacy devices, we use @vp_vdpa_set_vq_address to set vq
> > + * ready instead.
> > + */
> > + if (!ready)
> > + vp_legacy_set_queue_address(ldev, qid, 0);
> > +}
> > +
> > +static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + return vp_legacy_get_queue_enable(ldev, qid);
> > +}
> > +
> > +/* Legacy devices don't support set vq num by specification,
> > + * just report an error if someone try to set it.
> > + */
> > +static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
> > + u32 num)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + dev_err(&ldev->pci_dev->dev, "legacy device don't support set vq num\n");
> > +}
> > +
> > +static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + /* assume all virtqueues have the same size */
> > + return vp_legacy_get_queue_size(ldev, 0);
> > +}
> > +
> > +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_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + vp_legacy_set_queue_address(ldev, qid, desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
> > +
> > + return 0;
> > +}
> > +
> > +static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + return ldev->id.device;
> > +}
> > +
> > +static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > +
> > + return ldev->id.vendor;
> > +}
> > +
> > +static size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > + size_t size;
> > +
> > + switch (ldev->id.device) {
> > + case VIRTIO_ID_NET:
> > + size = sizeof(struct virtio_net_config);
> > + break;
> > + case VIRTIO_ID_BLOCK:
> > + size = sizeof(struct virtio_blk_config);
> > + break;
> > + default:
> > + size = 0;
> > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > + }
> > +
> > + return 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_legacy_device *ldev = &vp_vdpa->ldev;
> > + void __iomem *ioaddr = ldev->ioaddr +
> > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > + offset;
> > + u8 *p = buf;
> > + int i;
> > +
> > + /* legacy devices don't have a configuration generation field,
> > + * so we just read it once.
> > + */
> > + for (i = 0; i < len; i++)
> > + *p++ = ioread8(ioaddr + i);
> > +}
> > +
> > +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_legacy_device *ldev = &vp_vdpa->ldev;
> > + void __iomem *ioaddr = ldev->ioaddr +
> > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > + offset;
> > + const u8 *p = buf;
> > + int i;
> > +
> > + for (i = 0; i < len; i++)
> > + iowrite8(*p++, ioaddr + i);
> > +}
> > +
> > +static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
> > +{
> > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > + 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_legacy_set_status(ldev, status);
> > +
> > + if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > + (s & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > + vp_vdpa_free_irq(vp_vdpa);
> > + }
> > +}
> > +
> > +static bool vp_vdpa_get_vq_num_unchangeable(struct vdpa_device *vdpa)
> > +{
> > + return true;
> > +}
> > +
> > +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_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_size = vp_vdpa_get_config_size,
> > + .get_config = vp_vdpa_get_config,
> > + .set_config = vp_vdpa_set_config,
> > + .set_config_cb = vp_vdpa_set_config_cb,
> > + .get_vq_irq = vp_vdpa_get_vq_irq,
> > + .get_vq_num_unchangeable = vp_vdpa_get_vq_num_unchangeable,
> > +};
> > +
> > +static u16 vp_vdpa_get_num_queues(struct vp_vdpa *vp_vdpa)
> > +{
> > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > + u32 features = vp_legacy_get_features(ldev);
> > + u16 num;
> > +
> > + switch (ldev->id.device) {
> > + case VIRTIO_ID_NET:
> > + num = 2;
> > + if (features & VIRTIO_NET_F_MQ) {
> > + __virtio16 max_virtqueue_pairs;
> > +
> > + vp_vdpa_get_config(&vp_vdpa->vdpa,
> > + offsetof(struct virtio_net_config, max_virtqueue_pairs),
> > + &max_virtqueue_pairs,
> > + sizeof(max_virtqueue_pairs));
> > + num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
> > + max_virtqueue_pairs);
> > + }
> > +
> > + if (features & VIRTIO_NET_F_CTRL_VQ)
> > + num += 1;
> > + break;
> > + case VIRTIO_ID_BLOCK:
> > + num = 1;
> > + break;
> > + default:
> > + num = 0;
> > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > + }
> > +
> > + return num;
> > +}
> > +
> > +static u16 vp_vdpa_queue_vector(struct vp_vdpa *vp_vdpa, u16 idx, u16 vector)
> > +{
> > + return vp_legacy_queue_vector(&vp_vdpa->ldev, idx, vector);
> > +}
> > +
> > +static u16 vp_vdpa_config_vector(struct vp_vdpa *vp_vdpa, u16 vector)
> > +{
> > + return vp_legacy_config_vector(&vp_vdpa->ldev, vector);
> > +}
> > +
> > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct vp_vdpa *vp_vdpa;
> > + struct virtio_pci_legacy_device *ldev;
> > + int ret, i;
> > +
> > + vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, dev, &vp_vdpa_ops, NULL);
> > + if (vp_vdpa == NULL) {
> > + dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
> > + return ERR_PTR(-ENOMEM);
> > + }
> > +
> > + ldev = &vp_vdpa->ldev;
> > + ldev->pci_dev = pdev;
> > +
> > + ret = vp_legacy_probe(ldev);
> > + if (ret) {
> > + dev_err(dev, "Failed to probe legacy 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_vdpa_get_num_queues(vp_vdpa);
> > +
> > + ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
> > + if (ret) {
> > + dev_err(dev,
> > + "Failed for adding devres for freeing irq vectors\n");
> > + goto err;
> > + }
> > +
> > + vp_vdpa->vring = devm_kcalloc(dev, vp_vdpa->queues,
> > + sizeof(*vp_vdpa->vring),
> > + GFP_KERNEL);
> > + if (!vp_vdpa->vring) {
> > + ret = -ENOMEM;
> > + dev_err(dev, "Fail to allocate virtqueues\n");
> > + goto err;
> > + }
> > +
> > + for (i = 0; i < vp_vdpa->queues; i++) {
> > + vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
> > + vp_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
> > + vp_vdpa->vring[i].notify_pa = pci_resource_start(pdev, 0) + VIRTIO_PCI_QUEUE_NOTIFY;
> > + }
> > + vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
> > +
> > + vp_vdpa->queue_vector = vp_vdpa_queue_vector;
> > + vp_vdpa->config_vector = vp_vdpa_config_vector;
> > +
> > + return vp_vdpa;
> > +
> > +err:
> > + put_device(&vp_vdpa->vdpa.dev);
> > + return ERR_PTR(ret);
> > +}
> > --
> > 2.31.1
On Fri, Sep 10, 2021 at 10:28:18AM +0800, Wu Zongyong wrote:
> On Thu, Sep 09, 2021 at 09:57:50AM -0400, Michael S. Tsirkin wrote:
> > On Wed, Sep 08, 2021 at 08:20:37PM +0800, Wu Zongyong wrote:
> > > This patch implements a vdpa driver for legacy virtio-pci device. And
> > > this has been tested with the ENI(Elastic Network Interface) which is a
> > > hardware virtio network device in Alibaba ECS baremetal instance.
> > >
> > > Note that legacy device doesn't support to change the virtqueue size, so
> > > users should use get_vq_num_unchangeable callback to check if the
> > > virqueue size can be changed.
> >
> > Hmm isn't this implicit in this being a legacy device?
> >
> Yes, but there is no way to report the backend device is legacy for
> users. So I add a new callback get_vq_num_unchangeable to indicate it.
Legacy is actually easy. It does not have VIRTIO_F_VERSION_1.
Transitional devices with two interfaces are trickier.
These really need an ioctl so userspace can tell vdpa
whether it's being used through a legacy or modern interface.
> > > If not, users should get the virqueue size
> > > first by the get_vq_num_max callback first then allocate same size
> > > memory for the virtqueue otherwise the device won't work correctly.
> > >
> > > Signed-off-by: Wu Zongyong <[email protected]>
> > > ---
> > > drivers/vdpa/Kconfig | 7 +
> > > drivers/vdpa/virtio_pci/Makefile | 1 +
> > > drivers/vdpa/virtio_pci/vp_vdpa_common.c | 5 +
> > > drivers/vdpa/virtio_pci/vp_vdpa_common.h | 11 +
> > > drivers/vdpa/virtio_pci/vp_vdpa_legacy.c | 346 +++++++++++++++++++++++
> > > 5 files changed, 370 insertions(+)
> > > create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > >
> > > diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
> > > index a503c1b2bfd9..ccb4fdb11f0f 100644
> > > --- a/drivers/vdpa/Kconfig
> > > +++ b/drivers/vdpa/Kconfig
> > > @@ -67,4 +67,11 @@ config VP_VDPA
> > > help
> > > This kernel module bridges virtio PCI device to vDPA bus.
> > >
> > > +config VP_VDPA_LEGACY
> > > + bool "Support legacy virtio pci device"
> > > + depends on VP_VDPA
> > > + select VIRTIO_PCI_LIB_LEGACY
> > > + help
> > > + This option enables bridges legacy virito PCI device to vDPA bus.
> > > +
> > > endif # VDPA
> > > diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
> > > index a772d86952b1..77c52dfb8b56 100644
> > > --- a/drivers/vdpa/virtio_pci/Makefile
> > > +++ b/drivers/vdpa/virtio_pci/Makefile
> > > @@ -1,4 +1,5 @@
> > > # SPDX-License-Identifier: GPL-2.0
> > >
> > > vp_vdpa-y += vp_vdpa_common.o vp_vdpa_modern.o
> > > +vp_vdpa-$(CONFIG_VP_VDPA_LEGACY) += vp_vdpa_legacy.o
> > > obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
> > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.c b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > index 3ff24c9ad6e4..fa91dc153244 100644
> > > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > @@ -8,6 +8,7 @@
> > > * Based on virtio_pci_modern.c.
> > > */
> > >
> > > +#include "linux/err.h"
> > > #include <linux/irqreturn.h>
> > > #include <linux/interrupt.h>
> > > #include "vp_vdpa_common.h"
> > > @@ -172,6 +173,10 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> > > return ret;
> > >
> > > vp_vdpa = vp_vdpa_modern_probe(pdev);
> > > + if (PTR_ERR(vp_vdpa) == -ENODEV) {
> > > + dev_info(&pdev->dev, "Tring legacy driver");
> > > + vp_vdpa = vp_vdpa_legacy_probe(pdev);
> > > + }
> > > if (IS_ERR(vp_vdpa))
> > > return PTR_ERR(vp_vdpa);
> > >
> > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.h b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > index 57886b55a2e9..39f241d8321b 100644
> > > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > @@ -10,6 +10,7 @@
> > > #include <linux/virtio_ring.h>
> > > #include <linux/virtio_pci.h>
> > > #include <linux/virtio_pci_modern.h>
> > > +#include <linux/virtio_pci_legacy.h>
> > >
> > > #define VP_VDPA_DRIVER_NAME "vp_vdpa"
> > > #define VP_VDPA_NAME_SIZE 256
> > > @@ -26,6 +27,7 @@ struct vp_vdpa {
> > > struct vdpa_device vdpa;
> > > struct pci_dev *pci_dev;
> > > struct virtio_pci_modern_device mdev;
> > > + struct virtio_pci_legacy_device ldev;
> > > struct vp_vring *vring;
> > > struct vdpa_callback config_cb;
> > > char msix_name[VP_VDPA_NAME_SIZE];
> > > @@ -53,4 +55,13 @@ void vp_vdpa_free_irq_vectors(void *data);
> > >
> > > struct vp_vdpa *vp_vdpa_modern_probe(struct pci_dev *pdev);
> > >
> > > +#if IS_ENABLED(CONFIG_VP_VDPA_LEGACY)
> > > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev);
> > > +#else
> > > +static inline struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > > +{
> > > + return ERR_PTR(-ENODEV);
> > > +}
> > > +#endif
> > > +
> > > #endif
> > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > new file mode 100644
> > > index 000000000000..75a6879a27ca
> > > --- /dev/null
> > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > @@ -0,0 +1,346 @@
> > > +// SPDX-License-Identifier: GPL-2.0-only
> > > +/*
> > > + * vDPA bridge driver for legacy virtio-pci device
> > > + *
> > > + * Copyright (c) 2021, Alibaba Inc. All rights reserved.
> > > + * Author: Wu Zongyong <[email protected]>
> > > + */
> > > +
> > > +#include "linux/pci.h"
> > > +#include "linux/virtio_byteorder.h"
> > > +#include "linux/virtio_pci_legacy.h"
> > > +#include <uapi/linux/virtio_net.h>
> > > +#include <uapi/linux/virtio_blk.h>
> > > +#include <linux/virtio_ids.h>
> > > +#include <linux/virtio_pci.h>
> > > +#include "vp_vdpa_common.h"
> > > +
> > > +static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
> > > +{
> > > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > > +
> > > + return &vp_vdpa->ldev;
> > > +}
> > > +
> > > +static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + return vp_legacy_get_features(ldev);
> > > +}
> > > +
> > > +static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + vp_legacy_set_features(ldev, features);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + return vp_legacy_get_status(ldev);
> > > +}
> > > +
> > > +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
> > > + const struct vdpa_vq_state *state)
> > > +{
> > > + const struct vdpa_vq_state_split *split = &state->split;
> > > +
> > > + if (split->avail_index == 0)
> > > + return 0;
> > > +
> > > + return -EOPNOTSUPP;
> > > +}
> > > +
> > > +static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
> > > + const struct vdpa_vq_state *state)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + /* Note that this is not supported by virtio specification.
> > > + * But if the state is by chance equal to the device initial
> > > + * state, we can let it go.
> > > + */
> > > + if (!vp_legacy_get_queue_enable(ldev, qid))
> > > + return vp_vdpa_set_vq_state_split(vdpa, state);
> > > +
> > > + return -EOPNOTSUPP;
> > > +}
> > > +
> > > +static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
> > > + u16 qid, bool ready)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + /* Legacy devices can only be activated by setting vq address,
> > > + * and queue_enable is not supported by specification. So for
> > > + * legacy devices, we use @vp_vdpa_set_vq_address to set vq
> > > + * ready instead.
> > > + */
> > > + if (!ready)
> > > + vp_legacy_set_queue_address(ldev, qid, 0);
> > > +}
> > > +
> > > +static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + return vp_legacy_get_queue_enable(ldev, qid);
> > > +}
> > > +
> > > +/* Legacy devices don't support set vq num by specification,
> > > + * just report an error if someone try to set it.
> > > + */
> > > +static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
> > > + u32 num)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + dev_err(&ldev->pci_dev->dev, "legacy device don't support set vq num\n");
> > > +}
> > > +
> > > +static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + /* assume all virtqueues have the same size */
> > > + return vp_legacy_get_queue_size(ldev, 0);
> > > +}
> > > +
> > > +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_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + vp_legacy_set_queue_address(ldev, qid, desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + return ldev->id.device;
> > > +}
> > > +
> > > +static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > +
> > > + return ldev->id.vendor;
> > > +}
> > > +
> > > +static size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > + size_t size;
> > > +
> > > + switch (ldev->id.device) {
> > > + case VIRTIO_ID_NET:
> > > + size = sizeof(struct virtio_net_config);
> > > + break;
> > > + case VIRTIO_ID_BLOCK:
> > > + size = sizeof(struct virtio_blk_config);
> > > + break;
> > > + default:
> > > + size = 0;
> > > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > > + }
> > > +
> > > + return 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_legacy_device *ldev = &vp_vdpa->ldev;
> > > + void __iomem *ioaddr = ldev->ioaddr +
> > > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > > + offset;
> > > + u8 *p = buf;
> > > + int i;
> > > +
> > > + /* legacy devices don't have a configuration generation field,
> > > + * so we just read it once.
> > > + */
> > > + for (i = 0; i < len; i++)
> > > + *p++ = ioread8(ioaddr + i);
> > > +}
> > > +
> > > +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_legacy_device *ldev = &vp_vdpa->ldev;
> > > + void __iomem *ioaddr = ldev->ioaddr +
> > > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > > + offset;
> > > + const u8 *p = buf;
> > > + int i;
> > > +
> > > + for (i = 0; i < len; i++)
> > > + iowrite8(*p++, ioaddr + i);
> > > +}
> > > +
> > > +static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
> > > +{
> > > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > > + 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_legacy_set_status(ldev, status);
> > > +
> > > + if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > > + (s & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > > + vp_vdpa_free_irq(vp_vdpa);
> > > + }
> > > +}
> > > +
> > > +static bool vp_vdpa_get_vq_num_unchangeable(struct vdpa_device *vdpa)
> > > +{
> > > + return true;
> > > +}
> > > +
> > > +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_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_size = vp_vdpa_get_config_size,
> > > + .get_config = vp_vdpa_get_config,
> > > + .set_config = vp_vdpa_set_config,
> > > + .set_config_cb = vp_vdpa_set_config_cb,
> > > + .get_vq_irq = vp_vdpa_get_vq_irq,
> > > + .get_vq_num_unchangeable = vp_vdpa_get_vq_num_unchangeable,
> > > +};
> > > +
> > > +static u16 vp_vdpa_get_num_queues(struct vp_vdpa *vp_vdpa)
> > > +{
> > > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > > + u32 features = vp_legacy_get_features(ldev);
> > > + u16 num;
> > > +
> > > + switch (ldev->id.device) {
> > > + case VIRTIO_ID_NET:
> > > + num = 2;
> > > + if (features & VIRTIO_NET_F_MQ) {
> > > + __virtio16 max_virtqueue_pairs;
> > > +
> > > + vp_vdpa_get_config(&vp_vdpa->vdpa,
> > > + offsetof(struct virtio_net_config, max_virtqueue_pairs),
> > > + &max_virtqueue_pairs,
> > > + sizeof(max_virtqueue_pairs));
> > > + num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
> > > + max_virtqueue_pairs);
> > > + }
> > > +
> > > + if (features & VIRTIO_NET_F_CTRL_VQ)
> > > + num += 1;
> > > + break;
> > > + case VIRTIO_ID_BLOCK:
> > > + num = 1;
> > > + break;
> > > + default:
> > > + num = 0;
> > > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > > + }
> > > +
> > > + return num;
> > > +}
> > > +
> > > +static u16 vp_vdpa_queue_vector(struct vp_vdpa *vp_vdpa, u16 idx, u16 vector)
> > > +{
> > > + return vp_legacy_queue_vector(&vp_vdpa->ldev, idx, vector);
> > > +}
> > > +
> > > +static u16 vp_vdpa_config_vector(struct vp_vdpa *vp_vdpa, u16 vector)
> > > +{
> > > + return vp_legacy_config_vector(&vp_vdpa->ldev, vector);
> > > +}
> > > +
> > > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > > +{
> > > + struct device *dev = &pdev->dev;
> > > + struct vp_vdpa *vp_vdpa;
> > > + struct virtio_pci_legacy_device *ldev;
> > > + int ret, i;
> > > +
> > > + vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, dev, &vp_vdpa_ops, NULL);
> > > + if (vp_vdpa == NULL) {
> > > + dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
> > > + return ERR_PTR(-ENOMEM);
> > > + }
> > > +
> > > + ldev = &vp_vdpa->ldev;
> > > + ldev->pci_dev = pdev;
> > > +
> > > + ret = vp_legacy_probe(ldev);
> > > + if (ret) {
> > > + dev_err(dev, "Failed to probe legacy 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_vdpa_get_num_queues(vp_vdpa);
> > > +
> > > + ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
> > > + if (ret) {
> > > + dev_err(dev,
> > > + "Failed for adding devres for freeing irq vectors\n");
> > > + goto err;
> > > + }
> > > +
> > > + vp_vdpa->vring = devm_kcalloc(dev, vp_vdpa->queues,
> > > + sizeof(*vp_vdpa->vring),
> > > + GFP_KERNEL);
> > > + if (!vp_vdpa->vring) {
> > > + ret = -ENOMEM;
> > > + dev_err(dev, "Fail to allocate virtqueues\n");
> > > + goto err;
> > > + }
> > > +
> > > + for (i = 0; i < vp_vdpa->queues; i++) {
> > > + vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
> > > + vp_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
> > > + vp_vdpa->vring[i].notify_pa = pci_resource_start(pdev, 0) + VIRTIO_PCI_QUEUE_NOTIFY;
> > > + }
> > > + vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
> > > +
> > > + vp_vdpa->queue_vector = vp_vdpa_queue_vector;
> > > + vp_vdpa->config_vector = vp_vdpa_config_vector;
> > > +
> > > + return vp_vdpa;
> > > +
> > > +err:
> > > + put_device(&vp_vdpa->vdpa.dev);
> > > + return ERR_PTR(ret);
> > > +}
> > > --
> > > 2.31.1
On Fri, Sep 10, 2021 at 05:57:15AM -0400, Michael S. Tsirkin wrote:
> On Fri, Sep 10, 2021 at 10:28:18AM +0800, Wu Zongyong wrote:
> > On Thu, Sep 09, 2021 at 09:57:50AM -0400, Michael S. Tsirkin wrote:
> > > On Wed, Sep 08, 2021 at 08:20:37PM +0800, Wu Zongyong wrote:
> > > > This patch implements a vdpa driver for legacy virtio-pci device. And
> > > > this has been tested with the ENI(Elastic Network Interface) which is a
> > > > hardware virtio network device in Alibaba ECS baremetal instance.
> > > >
> > > > Note that legacy device doesn't support to change the virtqueue size, so
> > > > users should use get_vq_num_unchangeable callback to check if the
> > > > virqueue size can be changed.
> > >
> > > Hmm isn't this implicit in this being a legacy device?
> > >
> > Yes, but there is no way to report the backend device is legacy for
> > users. So I add a new callback get_vq_num_unchangeable to indicate it.
>
> Legacy is actually easy. It does not have VIRTIO_F_VERSION_1.
> Transitional devices with two interfaces are trickier.
>
> These really need an ioctl so userspace can tell vdpa
> whether it's being used through a legacy or modern interface.
>
You're right.
As Jason Wang suggested, I will implement a dedicated driver for Alibaba
ENI.
>
> > > > If not, users should get the virqueue size
> > > > first by the get_vq_num_max callback first then allocate same size
> > > > memory for the virtqueue otherwise the device won't work correctly.
> > > >
> > > > Signed-off-by: Wu Zongyong <[email protected]>
> > > > ---
> > > > drivers/vdpa/Kconfig | 7 +
> > > > drivers/vdpa/virtio_pci/Makefile | 1 +
> > > > drivers/vdpa/virtio_pci/vp_vdpa_common.c | 5 +
> > > > drivers/vdpa/virtio_pci/vp_vdpa_common.h | 11 +
> > > > drivers/vdpa/virtio_pci/vp_vdpa_legacy.c | 346 +++++++++++++++++++++++
> > > > 5 files changed, 370 insertions(+)
> > > > create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > >
> > > > diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
> > > > index a503c1b2bfd9..ccb4fdb11f0f 100644
> > > > --- a/drivers/vdpa/Kconfig
> > > > +++ b/drivers/vdpa/Kconfig
> > > > @@ -67,4 +67,11 @@ config VP_VDPA
> > > > help
> > > > This kernel module bridges virtio PCI device to vDPA bus.
> > > >
> > > > +config VP_VDPA_LEGACY
> > > > + bool "Support legacy virtio pci device"
> > > > + depends on VP_VDPA
> > > > + select VIRTIO_PCI_LIB_LEGACY
> > > > + help
> > > > + This option enables bridges legacy virito PCI device to vDPA bus.
> > > > +
> > > > endif # VDPA
> > > > diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
> > > > index a772d86952b1..77c52dfb8b56 100644
> > > > --- a/drivers/vdpa/virtio_pci/Makefile
> > > > +++ b/drivers/vdpa/virtio_pci/Makefile
> > > > @@ -1,4 +1,5 @@
> > > > # SPDX-License-Identifier: GPL-2.0
> > > >
> > > > vp_vdpa-y += vp_vdpa_common.o vp_vdpa_modern.o
> > > > +vp_vdpa-$(CONFIG_VP_VDPA_LEGACY) += vp_vdpa_legacy.o
> > > > obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
> > > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.c b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > > index 3ff24c9ad6e4..fa91dc153244 100644
> > > > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > > @@ -8,6 +8,7 @@
> > > > * Based on virtio_pci_modern.c.
> > > > */
> > > >
> > > > +#include "linux/err.h"
> > > > #include <linux/irqreturn.h>
> > > > #include <linux/interrupt.h>
> > > > #include "vp_vdpa_common.h"
> > > > @@ -172,6 +173,10 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> > > > return ret;
> > > >
> > > > vp_vdpa = vp_vdpa_modern_probe(pdev);
> > > > + if (PTR_ERR(vp_vdpa) == -ENODEV) {
> > > > + dev_info(&pdev->dev, "Tring legacy driver");
> > > > + vp_vdpa = vp_vdpa_legacy_probe(pdev);
> > > > + }
> > > > if (IS_ERR(vp_vdpa))
> > > > return PTR_ERR(vp_vdpa);
> > > >
> > > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.h b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > > index 57886b55a2e9..39f241d8321b 100644
> > > > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > > @@ -10,6 +10,7 @@
> > > > #include <linux/virtio_ring.h>
> > > > #include <linux/virtio_pci.h>
> > > > #include <linux/virtio_pci_modern.h>
> > > > +#include <linux/virtio_pci_legacy.h>
> > > >
> > > > #define VP_VDPA_DRIVER_NAME "vp_vdpa"
> > > > #define VP_VDPA_NAME_SIZE 256
> > > > @@ -26,6 +27,7 @@ struct vp_vdpa {
> > > > struct vdpa_device vdpa;
> > > > struct pci_dev *pci_dev;
> > > > struct virtio_pci_modern_device mdev;
> > > > + struct virtio_pci_legacy_device ldev;
> > > > struct vp_vring *vring;
> > > > struct vdpa_callback config_cb;
> > > > char msix_name[VP_VDPA_NAME_SIZE];
> > > > @@ -53,4 +55,13 @@ void vp_vdpa_free_irq_vectors(void *data);
> > > >
> > > > struct vp_vdpa *vp_vdpa_modern_probe(struct pci_dev *pdev);
> > > >
> > > > +#if IS_ENABLED(CONFIG_VP_VDPA_LEGACY)
> > > > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev);
> > > > +#else
> > > > +static inline struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > > > +{
> > > > + return ERR_PTR(-ENODEV);
> > > > +}
> > > > +#endif
> > > > +
> > > > #endif
> > > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > > new file mode 100644
> > > > index 000000000000..75a6879a27ca
> > > > --- /dev/null
> > > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > > @@ -0,0 +1,346 @@
> > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > +/*
> > > > + * vDPA bridge driver for legacy virtio-pci device
> > > > + *
> > > > + * Copyright (c) 2021, Alibaba Inc. All rights reserved.
> > > > + * Author: Wu Zongyong <[email protected]>
> > > > + */
> > > > +
> > > > +#include "linux/pci.h"
> > > > +#include "linux/virtio_byteorder.h"
> > > > +#include "linux/virtio_pci_legacy.h"
> > > > +#include <uapi/linux/virtio_net.h>
> > > > +#include <uapi/linux/virtio_blk.h>
> > > > +#include <linux/virtio_ids.h>
> > > > +#include <linux/virtio_pci.h>
> > > > +#include "vp_vdpa_common.h"
> > > > +
> > > > +static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > > > +
> > > > + return &vp_vdpa->ldev;
> > > > +}
> > > > +
> > > > +static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return vp_legacy_get_features(ldev);
> > > > +}
> > > > +
> > > > +static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + vp_legacy_set_features(ldev, features);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return vp_legacy_get_status(ldev);
> > > > +}
> > > > +
> > > > +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
> > > > + const struct vdpa_vq_state *state)
> > > > +{
> > > > + const struct vdpa_vq_state_split *split = &state->split;
> > > > +
> > > > + if (split->avail_index == 0)
> > > > + return 0;
> > > > +
> > > > + return -EOPNOTSUPP;
> > > > +}
> > > > +
> > > > +static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
> > > > + const struct vdpa_vq_state *state)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + /* Note that this is not supported by virtio specification.
> > > > + * But if the state is by chance equal to the device initial
> > > > + * state, we can let it go.
> > > > + */
> > > > + if (!vp_legacy_get_queue_enable(ldev, qid))
> > > > + return vp_vdpa_set_vq_state_split(vdpa, state);
> > > > +
> > > > + return -EOPNOTSUPP;
> > > > +}
> > > > +
> > > > +static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
> > > > + u16 qid, bool ready)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + /* Legacy devices can only be activated by setting vq address,
> > > > + * and queue_enable is not supported by specification. So for
> > > > + * legacy devices, we use @vp_vdpa_set_vq_address to set vq
> > > > + * ready instead.
> > > > + */
> > > > + if (!ready)
> > > > + vp_legacy_set_queue_address(ldev, qid, 0);
> > > > +}
> > > > +
> > > > +static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return vp_legacy_get_queue_enable(ldev, qid);
> > > > +}
> > > > +
> > > > +/* Legacy devices don't support set vq num by specification,
> > > > + * just report an error if someone try to set it.
> > > > + */
> > > > +static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
> > > > + u32 num)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + dev_err(&ldev->pci_dev->dev, "legacy device don't support set vq num\n");
> > > > +}
> > > > +
> > > > +static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + /* assume all virtqueues have the same size */
> > > > + return vp_legacy_get_queue_size(ldev, 0);
> > > > +}
> > > > +
> > > > +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_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + vp_legacy_set_queue_address(ldev, qid, desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return ldev->id.device;
> > > > +}
> > > > +
> > > > +static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return ldev->id.vendor;
> > > > +}
> > > > +
> > > > +static size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > + size_t size;
> > > > +
> > > > + switch (ldev->id.device) {
> > > > + case VIRTIO_ID_NET:
> > > > + size = sizeof(struct virtio_net_config);
> > > > + break;
> > > > + case VIRTIO_ID_BLOCK:
> > > > + size = sizeof(struct virtio_blk_config);
> > > > + break;
> > > > + default:
> > > > + size = 0;
> > > > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > > > + }
> > > > +
> > > > + return 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_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + void __iomem *ioaddr = ldev->ioaddr +
> > > > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > > > + offset;
> > > > + u8 *p = buf;
> > > > + int i;
> > > > +
> > > > + /* legacy devices don't have a configuration generation field,
> > > > + * so we just read it once.
> > > > + */
> > > > + for (i = 0; i < len; i++)
> > > > + *p++ = ioread8(ioaddr + i);
> > > > +}
> > > > +
> > > > +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_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + void __iomem *ioaddr = ldev->ioaddr +
> > > > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > > > + offset;
> > > > + const u8 *p = buf;
> > > > + int i;
> > > > +
> > > > + for (i = 0; i < len; i++)
> > > > + iowrite8(*p++, ioaddr + i);
> > > > +}
> > > > +
> > > > +static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
> > > > +{
> > > > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > > > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + 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_legacy_set_status(ldev, status);
> > > > +
> > > > + if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > > > + (s & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > > > + vp_vdpa_free_irq(vp_vdpa);
> > > > + }
> > > > +}
> > > > +
> > > > +static bool vp_vdpa_get_vq_num_unchangeable(struct vdpa_device *vdpa)
> > > > +{
> > > > + return true;
> > > > +}
> > > > +
> > > > +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_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_size = vp_vdpa_get_config_size,
> > > > + .get_config = vp_vdpa_get_config,
> > > > + .set_config = vp_vdpa_set_config,
> > > > + .set_config_cb = vp_vdpa_set_config_cb,
> > > > + .get_vq_irq = vp_vdpa_get_vq_irq,
> > > > + .get_vq_num_unchangeable = vp_vdpa_get_vq_num_unchangeable,
> > > > +};
> > > > +
> > > > +static u16 vp_vdpa_get_num_queues(struct vp_vdpa *vp_vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + u32 features = vp_legacy_get_features(ldev);
> > > > + u16 num;
> > > > +
> > > > + switch (ldev->id.device) {
> > > > + case VIRTIO_ID_NET:
> > > > + num = 2;
> > > > + if (features & VIRTIO_NET_F_MQ) {
> > > > + __virtio16 max_virtqueue_pairs;
> > > > +
> > > > + vp_vdpa_get_config(&vp_vdpa->vdpa,
> > > > + offsetof(struct virtio_net_config, max_virtqueue_pairs),
> > > > + &max_virtqueue_pairs,
> > > > + sizeof(max_virtqueue_pairs));
> > > > + num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
> > > > + max_virtqueue_pairs);
> > > > + }
> > > > +
> > > > + if (features & VIRTIO_NET_F_CTRL_VQ)
> > > > + num += 1;
> > > > + break;
> > > > + case VIRTIO_ID_BLOCK:
> > > > + num = 1;
> > > > + break;
> > > > + default:
> > > > + num = 0;
> > > > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > > > + }
> > > > +
> > > > + return num;
> > > > +}
> > > > +
> > > > +static u16 vp_vdpa_queue_vector(struct vp_vdpa *vp_vdpa, u16 idx, u16 vector)
> > > > +{
> > > > + return vp_legacy_queue_vector(&vp_vdpa->ldev, idx, vector);
> > > > +}
> > > > +
> > > > +static u16 vp_vdpa_config_vector(struct vp_vdpa *vp_vdpa, u16 vector)
> > > > +{
> > > > + return vp_legacy_config_vector(&vp_vdpa->ldev, vector);
> > > > +}
> > > > +
> > > > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > > > +{
> > > > + struct device *dev = &pdev->dev;
> > > > + struct vp_vdpa *vp_vdpa;
> > > > + struct virtio_pci_legacy_device *ldev;
> > > > + int ret, i;
> > > > +
> > > > + vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, dev, &vp_vdpa_ops, NULL);
> > > > + if (vp_vdpa == NULL) {
> > > > + dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
> > > > + return ERR_PTR(-ENOMEM);
> > > > + }
> > > > +
> > > > + ldev = &vp_vdpa->ldev;
> > > > + ldev->pci_dev = pdev;
> > > > +
> > > > + ret = vp_legacy_probe(ldev);
> > > > + if (ret) {
> > > > + dev_err(dev, "Failed to probe legacy 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_vdpa_get_num_queues(vp_vdpa);
> > > > +
> > > > + ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
> > > > + if (ret) {
> > > > + dev_err(dev,
> > > > + "Failed for adding devres for freeing irq vectors\n");
> > > > + goto err;
> > > > + }
> > > > +
> > > > + vp_vdpa->vring = devm_kcalloc(dev, vp_vdpa->queues,
> > > > + sizeof(*vp_vdpa->vring),
> > > > + GFP_KERNEL);
> > > > + if (!vp_vdpa->vring) {
> > > > + ret = -ENOMEM;
> > > > + dev_err(dev, "Fail to allocate virtqueues\n");
> > > > + goto err;
> > > > + }
> > > > +
> > > > + for (i = 0; i < vp_vdpa->queues; i++) {
> > > > + vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
> > > > + vp_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
> > > > + vp_vdpa->vring[i].notify_pa = pci_resource_start(pdev, 0) + VIRTIO_PCI_QUEUE_NOTIFY;
> > > > + }
> > > > + vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
> > > > +
> > > > + vp_vdpa->queue_vector = vp_vdpa_queue_vector;
> > > > + vp_vdpa->config_vector = vp_vdpa_config_vector;
> > > > +
> > > > + return vp_vdpa;
> > > > +
> > > > +err:
> > > > + put_device(&vp_vdpa->vdpa.dev);
> > > > + return ERR_PTR(ret);
> > > > +}
> > > > --
> > > > 2.31.1
On Fri, Sep 10, 2021 at 05:57:20AM -0400, Michael S. Tsirkin wrote:
> On Fri, Sep 10, 2021 at 10:28:18AM +0800, Wu Zongyong wrote:
> > On Thu, Sep 09, 2021 at 09:57:50AM -0400, Michael S. Tsirkin wrote:
> > > On Wed, Sep 08, 2021 at 08:20:37PM +0800, Wu Zongyong wrote:
> > > > This patch implements a vdpa driver for legacy virtio-pci device. And
> > > > this has been tested with the ENI(Elastic Network Interface) which is a
> > > > hardware virtio network device in Alibaba ECS baremetal instance.
> > > >
> > > > Note that legacy device doesn't support to change the virtqueue size, so
> > > > users should use get_vq_num_unchangeable callback to check if the
> > > > virqueue size can be changed.
> > >
> > > Hmm isn't this implicit in this being a legacy device?
> > >
> > Yes, but there is no way to report the backend device is legacy for
> > users. So I add a new callback get_vq_num_unchangeable to indicate it.
>
> Legacy is actually easy. It does not have VIRTIO_F_VERSION_1.
> Transitional devices with two interfaces are trickier.
>
> These really need an ioctl so userspace can tell vdpa
> whether it's being used through a legacy or modern interface.
Recently I proposed that a SET_FEATURES ioctl is used by QEMU when
guest accesses the device: through modern with VIRTIO_F_VERSION_1,
through legacy without.
What do you think?
>
> > > > If not, users should get the virqueue size
> > > > first by the get_vq_num_max callback first then allocate same size
> > > > memory for the virtqueue otherwise the device won't work correctly.
> > > >
> > > > Signed-off-by: Wu Zongyong <[email protected]>
> > > > ---
> > > > drivers/vdpa/Kconfig | 7 +
> > > > drivers/vdpa/virtio_pci/Makefile | 1 +
> > > > drivers/vdpa/virtio_pci/vp_vdpa_common.c | 5 +
> > > > drivers/vdpa/virtio_pci/vp_vdpa_common.h | 11 +
> > > > drivers/vdpa/virtio_pci/vp_vdpa_legacy.c | 346 +++++++++++++++++++++++
> > > > 5 files changed, 370 insertions(+)
> > > > create mode 100644 drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > >
> > > > diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig
> > > > index a503c1b2bfd9..ccb4fdb11f0f 100644
> > > > --- a/drivers/vdpa/Kconfig
> > > > +++ b/drivers/vdpa/Kconfig
> > > > @@ -67,4 +67,11 @@ config VP_VDPA
> > > > help
> > > > This kernel module bridges virtio PCI device to vDPA bus.
> > > >
> > > > +config VP_VDPA_LEGACY
> > > > + bool "Support legacy virtio pci device"
> > > > + depends on VP_VDPA
> > > > + select VIRTIO_PCI_LIB_LEGACY
> > > > + help
> > > > + This option enables bridges legacy virito PCI device to vDPA bus.
> > > > +
> > > > endif # VDPA
> > > > diff --git a/drivers/vdpa/virtio_pci/Makefile b/drivers/vdpa/virtio_pci/Makefile
> > > > index a772d86952b1..77c52dfb8b56 100644
> > > > --- a/drivers/vdpa/virtio_pci/Makefile
> > > > +++ b/drivers/vdpa/virtio_pci/Makefile
> > > > @@ -1,4 +1,5 @@
> > > > # SPDX-License-Identifier: GPL-2.0
> > > >
> > > > vp_vdpa-y += vp_vdpa_common.o vp_vdpa_modern.o
> > > > +vp_vdpa-$(CONFIG_VP_VDPA_LEGACY) += vp_vdpa_legacy.o
> > > > obj-$(CONFIG_VP_VDPA) += vp_vdpa.o
> > > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.c b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > > index 3ff24c9ad6e4..fa91dc153244 100644
> > > > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.c
> > > > @@ -8,6 +8,7 @@
> > > > * Based on virtio_pci_modern.c.
> > > > */
> > > >
> > > > +#include "linux/err.h"
> > > > #include <linux/irqreturn.h>
> > > > #include <linux/interrupt.h>
> > > > #include "vp_vdpa_common.h"
> > > > @@ -172,6 +173,10 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> > > > return ret;
> > > >
> > > > vp_vdpa = vp_vdpa_modern_probe(pdev);
> > > > + if (PTR_ERR(vp_vdpa) == -ENODEV) {
> > > > + dev_info(&pdev->dev, "Tring legacy driver");
> > > > + vp_vdpa = vp_vdpa_legacy_probe(pdev);
> > > > + }
> > > > if (IS_ERR(vp_vdpa))
> > > > return PTR_ERR(vp_vdpa);
> > > >
> > > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_common.h b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > > index 57886b55a2e9..39f241d8321b 100644
> > > > --- a/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_common.h
> > > > @@ -10,6 +10,7 @@
> > > > #include <linux/virtio_ring.h>
> > > > #include <linux/virtio_pci.h>
> > > > #include <linux/virtio_pci_modern.h>
> > > > +#include <linux/virtio_pci_legacy.h>
> > > >
> > > > #define VP_VDPA_DRIVER_NAME "vp_vdpa"
> > > > #define VP_VDPA_NAME_SIZE 256
> > > > @@ -26,6 +27,7 @@ struct vp_vdpa {
> > > > struct vdpa_device vdpa;
> > > > struct pci_dev *pci_dev;
> > > > struct virtio_pci_modern_device mdev;
> > > > + struct virtio_pci_legacy_device ldev;
> > > > struct vp_vring *vring;
> > > > struct vdpa_callback config_cb;
> > > > char msix_name[VP_VDPA_NAME_SIZE];
> > > > @@ -53,4 +55,13 @@ void vp_vdpa_free_irq_vectors(void *data);
> > > >
> > > > struct vp_vdpa *vp_vdpa_modern_probe(struct pci_dev *pdev);
> > > >
> > > > +#if IS_ENABLED(CONFIG_VP_VDPA_LEGACY)
> > > > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev);
> > > > +#else
> > > > +static inline struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > > > +{
> > > > + return ERR_PTR(-ENODEV);
> > > > +}
> > > > +#endif
> > > > +
> > > > #endif
> > > > diff --git a/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > > new file mode 100644
> > > > index 000000000000..75a6879a27ca
> > > > --- /dev/null
> > > > +++ b/drivers/vdpa/virtio_pci/vp_vdpa_legacy.c
> > > > @@ -0,0 +1,346 @@
> > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > +/*
> > > > + * vDPA bridge driver for legacy virtio-pci device
> > > > + *
> > > > + * Copyright (c) 2021, Alibaba Inc. All rights reserved.
> > > > + * Author: Wu Zongyong <[email protected]>
> > > > + */
> > > > +
> > > > +#include "linux/pci.h"
> > > > +#include "linux/virtio_byteorder.h"
> > > > +#include "linux/virtio_pci_legacy.h"
> > > > +#include <uapi/linux/virtio_net.h>
> > > > +#include <uapi/linux/virtio_blk.h>
> > > > +#include <linux/virtio_ids.h>
> > > > +#include <linux/virtio_pci.h>
> > > > +#include "vp_vdpa_common.h"
> > > > +
> > > > +static struct virtio_pci_legacy_device *vdpa_to_ldev(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > > > +
> > > > + return &vp_vdpa->ldev;
> > > > +}
> > > > +
> > > > +static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return vp_legacy_get_features(ldev);
> > > > +}
> > > > +
> > > > +static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + vp_legacy_set_features(ldev, features);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return vp_legacy_get_status(ldev);
> > > > +}
> > > > +
> > > > +static int vp_vdpa_set_vq_state_split(struct vdpa_device *vdpa,
> > > > + const struct vdpa_vq_state *state)
> > > > +{
> > > > + const struct vdpa_vq_state_split *split = &state->split;
> > > > +
> > > > + if (split->avail_index == 0)
> > > > + return 0;
> > > > +
> > > > + return -EOPNOTSUPP;
> > > > +}
> > > > +
> > > > +static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
> > > > + const struct vdpa_vq_state *state)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + /* Note that this is not supported by virtio specification.
> > > > + * But if the state is by chance equal to the device initial
> > > > + * state, we can let it go.
> > > > + */
> > > > + if (!vp_legacy_get_queue_enable(ldev, qid))
> > > > + return vp_vdpa_set_vq_state_split(vdpa, state);
> > > > +
> > > > + return -EOPNOTSUPP;
> > > > +}
> > > > +
> > > > +static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
> > > > + u16 qid, bool ready)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + /* Legacy devices can only be activated by setting vq address,
> > > > + * and queue_enable is not supported by specification. So for
> > > > + * legacy devices, we use @vp_vdpa_set_vq_address to set vq
> > > > + * ready instead.
> > > > + */
> > > > + if (!ready)
> > > > + vp_legacy_set_queue_address(ldev, qid, 0);
> > > > +}
> > > > +
> > > > +static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return vp_legacy_get_queue_enable(ldev, qid);
> > > > +}
> > > > +
> > > > +/* Legacy devices don't support set vq num by specification,
> > > > + * just report an error if someone try to set it.
> > > > + */
> > > > +static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
> > > > + u32 num)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + dev_err(&ldev->pci_dev->dev, "legacy device don't support set vq num\n");
> > > > +}
> > > > +
> > > > +static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + /* assume all virtqueues have the same size */
> > > > + return vp_legacy_get_queue_size(ldev, 0);
> > > > +}
> > > > +
> > > > +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_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + vp_legacy_set_queue_address(ldev, qid, desc_area >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return ldev->id.device;
> > > > +}
> > > > +
> > > > +static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > +
> > > > + return ldev->id.vendor;
> > > > +}
> > > > +
> > > > +static size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = vdpa_to_ldev(vdpa);
> > > > + size_t size;
> > > > +
> > > > + switch (ldev->id.device) {
> > > > + case VIRTIO_ID_NET:
> > > > + size = sizeof(struct virtio_net_config);
> > > > + break;
> > > > + case VIRTIO_ID_BLOCK:
> > > > + size = sizeof(struct virtio_blk_config);
> > > > + break;
> > > > + default:
> > > > + size = 0;
> > > > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > > > + }
> > > > +
> > > > + return 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_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + void __iomem *ioaddr = ldev->ioaddr +
> > > > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > > > + offset;
> > > > + u8 *p = buf;
> > > > + int i;
> > > > +
> > > > + /* legacy devices don't have a configuration generation field,
> > > > + * so we just read it once.
> > > > + */
> > > > + for (i = 0; i < len; i++)
> > > > + *p++ = ioread8(ioaddr + i);
> > > > +}
> > > > +
> > > > +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_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + void __iomem *ioaddr = ldev->ioaddr +
> > > > + VIRTIO_PCI_CONFIG_OFF(vp_vdpa->vectors) +
> > > > + offset;
> > > > + const u8 *p = buf;
> > > > + int i;
> > > > +
> > > > + for (i = 0; i < len; i++)
> > > > + iowrite8(*p++, ioaddr + i);
> > > > +}
> > > > +
> > > > +static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
> > > > +{
> > > > + struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> > > > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + 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_legacy_set_status(ldev, status);
> > > > +
> > > > + if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
> > > > + (s & VIRTIO_CONFIG_S_DRIVER_OK)) {
> > > > + vp_vdpa_free_irq(vp_vdpa);
> > > > + }
> > > > +}
> > > > +
> > > > +static bool vp_vdpa_get_vq_num_unchangeable(struct vdpa_device *vdpa)
> > > > +{
> > > > + return true;
> > > > +}
> > > > +
> > > > +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_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_size = vp_vdpa_get_config_size,
> > > > + .get_config = vp_vdpa_get_config,
> > > > + .set_config = vp_vdpa_set_config,
> > > > + .set_config_cb = vp_vdpa_set_config_cb,
> > > > + .get_vq_irq = vp_vdpa_get_vq_irq,
> > > > + .get_vq_num_unchangeable = vp_vdpa_get_vq_num_unchangeable,
> > > > +};
> > > > +
> > > > +static u16 vp_vdpa_get_num_queues(struct vp_vdpa *vp_vdpa)
> > > > +{
> > > > + struct virtio_pci_legacy_device *ldev = &vp_vdpa->ldev;
> > > > + u32 features = vp_legacy_get_features(ldev);
> > > > + u16 num;
> > > > +
> > > > + switch (ldev->id.device) {
> > > > + case VIRTIO_ID_NET:
> > > > + num = 2;
> > > > + if (features & VIRTIO_NET_F_MQ) {
> > > > + __virtio16 max_virtqueue_pairs;
> > > > +
> > > > + vp_vdpa_get_config(&vp_vdpa->vdpa,
> > > > + offsetof(struct virtio_net_config, max_virtqueue_pairs),
> > > > + &max_virtqueue_pairs,
> > > > + sizeof(max_virtqueue_pairs));
> > > > + num = 2 * __virtio16_to_cpu(virtio_legacy_is_little_endian(),
> > > > + max_virtqueue_pairs);
> > > > + }
> > > > +
> > > > + if (features & VIRTIO_NET_F_CTRL_VQ)
> > > > + num += 1;
> > > > + break;
> > > > + case VIRTIO_ID_BLOCK:
> > > > + num = 1;
> > > > + break;
> > > > + default:
> > > > + num = 0;
> > > > + dev_err(&ldev->pci_dev->dev, "VIRTIO ID %u not support\n", ldev->id.device);
> > > > + }
> > > > +
> > > > + return num;
> > > > +}
> > > > +
> > > > +static u16 vp_vdpa_queue_vector(struct vp_vdpa *vp_vdpa, u16 idx, u16 vector)
> > > > +{
> > > > + return vp_legacy_queue_vector(&vp_vdpa->ldev, idx, vector);
> > > > +}
> > > > +
> > > > +static u16 vp_vdpa_config_vector(struct vp_vdpa *vp_vdpa, u16 vector)
> > > > +{
> > > > + return vp_legacy_config_vector(&vp_vdpa->ldev, vector);
> > > > +}
> > > > +
> > > > +struct vp_vdpa *vp_vdpa_legacy_probe(struct pci_dev *pdev)
> > > > +{
> > > > + struct device *dev = &pdev->dev;
> > > > + struct vp_vdpa *vp_vdpa;
> > > > + struct virtio_pci_legacy_device *ldev;
> > > > + int ret, i;
> > > > +
> > > > + vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa, dev, &vp_vdpa_ops, NULL);
> > > > + if (vp_vdpa == NULL) {
> > > > + dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
> > > > + return ERR_PTR(-ENOMEM);
> > > > + }
> > > > +
> > > > + ldev = &vp_vdpa->ldev;
> > > > + ldev->pci_dev = pdev;
> > > > +
> > > > + ret = vp_legacy_probe(ldev);
> > > > + if (ret) {
> > > > + dev_err(dev, "Failed to probe legacy 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_vdpa_get_num_queues(vp_vdpa);
> > > > +
> > > > + ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
> > > > + if (ret) {
> > > > + dev_err(dev,
> > > > + "Failed for adding devres for freeing irq vectors\n");
> > > > + goto err;
> > > > + }
> > > > +
> > > > + vp_vdpa->vring = devm_kcalloc(dev, vp_vdpa->queues,
> > > > + sizeof(*vp_vdpa->vring),
> > > > + GFP_KERNEL);
> > > > + if (!vp_vdpa->vring) {
> > > > + ret = -ENOMEM;
> > > > + dev_err(dev, "Fail to allocate virtqueues\n");
> > > > + goto err;
> > > > + }
> > > > +
> > > > + for (i = 0; i < vp_vdpa->queues; i++) {
> > > > + vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
> > > > + vp_vdpa->vring[i].notify = ldev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
> > > > + vp_vdpa->vring[i].notify_pa = pci_resource_start(pdev, 0) + VIRTIO_PCI_QUEUE_NOTIFY;
> > > > + }
> > > > + vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
> > > > +
> > > > + vp_vdpa->queue_vector = vp_vdpa_queue_vector;
> > > > + vp_vdpa->config_vector = vp_vdpa_config_vector;
> > > > +
> > > > + return vp_vdpa;
> > > > +
> > > > +err:
> > > > + put_device(&vp_vdpa->vdpa.dev);
> > > > + return ERR_PTR(ret);
> > > > +}
> > > > --
> > > > 2.31.1