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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 13:43:55 +08:00

vdpa: introduce virtio pci driver

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

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

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210223061905.422659-4-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Jason Wang 2021-02-23 14:19:05 +08:00 committed by Michael S. Tsirkin
parent 9f4ad9e425
commit 64b9f64f80
5 changed files with 469 additions and 0 deletions

View File

@ -42,6 +42,7 @@ obj-$(CONFIG_DMADEVICES) += dma/
obj-y += soc/
obj-$(CONFIG_VIRTIO) += virtio/
obj-$(CONFIG_VIRTIO_PCI_LIB) += virtio/
obj-$(CONFIG_VDPA) += vdpa/
obj-$(CONFIG_XEN) += xen/

View File

@ -52,4 +52,11 @@ config MLX5_VDPA_NET
be executed by the hardware. It also supports a variety of stateless
offloads depending on the actual device used and firmware version.
config VP_VDPA
tristate "Virtio PCI bridge vDPA driver"
select VIRTIO_PCI_LIB
depends on PCI_MSI
help
This kernel module bridges virtio PCI device to vDPA bus.
endif # VDPA

View File

@ -3,3 +3,4 @@ obj-$(CONFIG_VDPA) += vdpa.o
obj-$(CONFIG_VDPA_SIM) += vdpa_sim/
obj-$(CONFIG_IFCVF) += ifcvf/
obj-$(CONFIG_MLX5_VDPA) += mlx5/
obj-$(CONFIG_VP_VDPA) += virtio_pci/

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@ -0,0 +1,2 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_VP_VDPA) += vp_vdpa.o

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@ -0,0 +1,458 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* vDPA bridge driver for modern virtio-pci device
*
* Copyright (c) 2020, Red Hat Inc. All rights reserved.
* Author: Jason Wang <jasowang@redhat.com>
*
* Based on virtio_pci_modern.c.
*/
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/vdpa.h>
#include <linux/virtio.h>
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/virtio_pci.h>
#include <linux/virtio_pci_modern.h>
#define VP_VDPA_QUEUE_MAX 256
#define VP_VDPA_DRIVER_NAME "vp_vdpa"
#define VP_VDPA_NAME_SIZE 256
struct vp_vring {
void __iomem *notify;
char msix_name[VP_VDPA_NAME_SIZE];
struct vdpa_callback cb;
int irq;
};
struct vp_vdpa {
struct vdpa_device vdpa;
struct virtio_pci_modern_device mdev;
struct vp_vring *vring;
struct vdpa_callback config_cb;
char msix_name[VP_VDPA_NAME_SIZE];
int config_irq;
int queues;
int vectors;
};
static struct vp_vdpa *vdpa_to_vp(struct vdpa_device *vdpa)
{
return container_of(vdpa, struct vp_vdpa, vdpa);
}
static struct virtio_pci_modern_device *vdpa_to_mdev(struct vdpa_device *vdpa)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
return &vp_vdpa->mdev;
}
static u64 vp_vdpa_get_features(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return vp_modern_get_features(mdev);
}
static int vp_vdpa_set_features(struct vdpa_device *vdpa, u64 features)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
vp_modern_set_features(mdev, features);
return 0;
}
static u8 vp_vdpa_get_status(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return vp_modern_get_status(mdev);
}
static void vp_vdpa_free_irq(struct vp_vdpa *vp_vdpa)
{
struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
struct pci_dev *pdev = mdev->pci_dev;
int i;
for (i = 0; i < vp_vdpa->queues; i++) {
if (vp_vdpa->vring[i].irq != VIRTIO_MSI_NO_VECTOR) {
vp_modern_queue_vector(mdev, i, VIRTIO_MSI_NO_VECTOR);
devm_free_irq(&pdev->dev, vp_vdpa->vring[i].irq,
&vp_vdpa->vring[i]);
vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
}
}
if (vp_vdpa->config_irq != VIRTIO_MSI_NO_VECTOR) {
vp_modern_config_vector(mdev, VIRTIO_MSI_NO_VECTOR);
devm_free_irq(&pdev->dev, vp_vdpa->config_irq, vp_vdpa);
vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
}
if (vp_vdpa->vectors) {
pci_free_irq_vectors(pdev);
vp_vdpa->vectors = 0;
}
}
static irqreturn_t vp_vdpa_vq_handler(int irq, void *arg)
{
struct vp_vring *vring = arg;
if (vring->cb.callback)
return vring->cb.callback(vring->cb.private);
return IRQ_HANDLED;
}
static irqreturn_t vp_vdpa_config_handler(int irq, void *arg)
{
struct vp_vdpa *vp_vdpa = arg;
if (vp_vdpa->config_cb.callback)
return vp_vdpa->config_cb.callback(vp_vdpa->config_cb.private);
return IRQ_HANDLED;
}
static int vp_vdpa_request_irq(struct vp_vdpa *vp_vdpa)
{
struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
struct pci_dev *pdev = mdev->pci_dev;
int i, ret, irq;
int queues = vp_vdpa->queues;
int vectors = queues + 1;
ret = pci_alloc_irq_vectors(pdev, vectors, vectors, PCI_IRQ_MSIX);
if (ret != vectors) {
dev_err(&pdev->dev,
"vp_vdpa: fail to allocate irq vectors want %d but %d\n",
vectors, ret);
return ret;
}
vp_vdpa->vectors = vectors;
for (i = 0; i < queues; i++) {
snprintf(vp_vdpa->vring[i].msix_name, VP_VDPA_NAME_SIZE,
"vp-vdpa[%s]-%d\n", pci_name(pdev), i);
irq = pci_irq_vector(pdev, i);
ret = devm_request_irq(&pdev->dev, irq,
vp_vdpa_vq_handler,
0, vp_vdpa->vring[i].msix_name,
&vp_vdpa->vring[i]);
if (ret) {
dev_err(&pdev->dev,
"vp_vdpa: fail to request irq for vq %d\n", i);
goto err;
}
vp_modern_queue_vector(mdev, i, i);
vp_vdpa->vring[i].irq = irq;
}
snprintf(vp_vdpa->msix_name, VP_VDPA_NAME_SIZE, "vp-vdpa[%s]-config\n",
pci_name(pdev));
irq = pci_irq_vector(pdev, queues);
ret = devm_request_irq(&pdev->dev, irq, vp_vdpa_config_handler, 0,
vp_vdpa->msix_name, vp_vdpa);
if (ret) {
dev_err(&pdev->dev,
"vp_vdpa: fail to request irq for vq %d\n", i);
goto err;
}
vp_modern_config_vector(mdev, queues);
vp_vdpa->config_irq = irq;
return 0;
err:
vp_vdpa_free_irq(vp_vdpa);
return ret;
}
static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
u8 s = vp_vdpa_get_status(vdpa);
if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
!(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
vp_vdpa_request_irq(vp_vdpa);
}
vp_modern_set_status(mdev, status);
if (!(status & VIRTIO_CONFIG_S_DRIVER_OK) &&
(s & VIRTIO_CONFIG_S_DRIVER_OK))
vp_vdpa_free_irq(vp_vdpa);
}
static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
{
return VP_VDPA_QUEUE_MAX;
}
static int vp_vdpa_get_vq_state(struct vdpa_device *vdpa, u16 qid,
struct vdpa_vq_state *state)
{
/* Note that this is not supported by virtio specification, so
* we return -EOPNOTSUPP here. This means we can't support live
* migration, vhost device start/stop.
*/
return -EOPNOTSUPP;
}
static int vp_vdpa_set_vq_state(struct vdpa_device *vdpa, u16 qid,
const struct vdpa_vq_state *state)
{
/* Note that this is not supported by virtio specification, so
* we return -ENOPOTSUPP here. This means we can't support live
* migration, vhost device start/stop.
*/
return -EOPNOTSUPP;
}
static void vp_vdpa_set_vq_cb(struct vdpa_device *vdpa, u16 qid,
struct vdpa_callback *cb)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
vp_vdpa->vring[qid].cb = *cb;
}
static void vp_vdpa_set_vq_ready(struct vdpa_device *vdpa,
u16 qid, bool ready)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
vp_modern_set_queue_enable(mdev, qid, ready);
}
static bool vp_vdpa_get_vq_ready(struct vdpa_device *vdpa, u16 qid)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return vp_modern_get_queue_enable(mdev, qid);
}
static void vp_vdpa_set_vq_num(struct vdpa_device *vdpa, u16 qid,
u32 num)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
vp_modern_set_queue_size(mdev, qid, num);
}
static int vp_vdpa_set_vq_address(struct vdpa_device *vdpa, u16 qid,
u64 desc_area, u64 driver_area,
u64 device_area)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
vp_modern_queue_address(mdev, qid, desc_area,
driver_area, device_area);
return 0;
}
static void vp_vdpa_kick_vq(struct vdpa_device *vdpa, u16 qid)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
vp_iowrite16(qid, vp_vdpa->vring[qid].notify);
}
static u32 vp_vdpa_get_generation(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return vp_modern_generation(mdev);
}
static u32 vp_vdpa_get_device_id(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return mdev->id.device;
}
static u32 vp_vdpa_get_vendor_id(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return mdev->id.vendor;
}
static u32 vp_vdpa_get_vq_align(struct vdpa_device *vdpa)
{
return PAGE_SIZE;
}
static void vp_vdpa_get_config(struct vdpa_device *vdpa,
unsigned int offset,
void *buf, unsigned int len)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
u8 old, new;
u8 *p;
int i;
do {
old = vp_ioread8(&mdev->common->config_generation);
p = buf;
for (i = 0; i < len; i++)
*p++ = vp_ioread8(mdev->device + offset + i);
new = vp_ioread8(&mdev->common->config_generation);
} while (old != new);
}
static void vp_vdpa_set_config(struct vdpa_device *vdpa,
unsigned int offset, const void *buf,
unsigned int len)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
const u8 *p = buf;
int i;
for (i = 0; i < len; i++)
vp_iowrite8(*p++, mdev->device + offset + i);
}
static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa,
struct vdpa_callback *cb)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
vp_vdpa->config_cb = *cb;
}
static const struct vdpa_config_ops vp_vdpa_ops = {
.get_features = vp_vdpa_get_features,
.set_features = vp_vdpa_set_features,
.get_status = vp_vdpa_get_status,
.set_status = vp_vdpa_set_status,
.get_vq_num_max = vp_vdpa_get_vq_num_max,
.get_vq_state = vp_vdpa_get_vq_state,
.set_vq_state = vp_vdpa_set_vq_state,
.set_vq_cb = vp_vdpa_set_vq_cb,
.set_vq_ready = vp_vdpa_set_vq_ready,
.get_vq_ready = vp_vdpa_get_vq_ready,
.set_vq_num = vp_vdpa_set_vq_num,
.set_vq_address = vp_vdpa_set_vq_address,
.kick_vq = vp_vdpa_kick_vq,
.get_generation = vp_vdpa_get_generation,
.get_device_id = vp_vdpa_get_device_id,
.get_vendor_id = vp_vdpa_get_vendor_id,
.get_vq_align = vp_vdpa_get_vq_align,
.get_config = vp_vdpa_get_config,
.set_config = vp_vdpa_set_config,
.set_config_cb = vp_vdpa_set_config_cb,
};
static void vp_vdpa_free_irq_vectors(void *data)
{
pci_free_irq_vectors(data);
}
static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct virtio_pci_modern_device *mdev;
struct device *dev = &pdev->dev;
struct vp_vdpa *vp_vdpa;
u16 notify_off;
int ret, i;
ret = pcim_enable_device(pdev);
if (ret)
return ret;
vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
dev, &vp_vdpa_ops, NULL);
if (vp_vdpa == NULL) {
dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
return -ENOMEM;
}
mdev = &vp_vdpa->mdev;
mdev->pci_dev = pdev;
ret = vp_modern_probe(mdev);
if (ret) {
dev_err(&pdev->dev, "Failed to probe modern PCI device\n");
goto err;
}
pci_set_master(pdev);
pci_set_drvdata(pdev, vp_vdpa);
vp_vdpa->vdpa.dma_dev = &pdev->dev;
vp_vdpa->queues = vp_modern_get_num_queues(mdev);
ret = devm_add_action_or_reset(dev, vp_vdpa_free_irq_vectors, pdev);
if (ret) {
dev_err(&pdev->dev,
"Failed for adding devres for freeing irq vectors\n");
goto err;
}
vp_vdpa->vring = devm_kcalloc(&pdev->dev, vp_vdpa->queues,
sizeof(*vp_vdpa->vring),
GFP_KERNEL);
if (!vp_vdpa->vring) {
ret = -ENOMEM;
dev_err(&pdev->dev, "Fail to allocate virtqueues\n");
goto err;
}
for (i = 0; i < vp_vdpa->queues; i++) {
notify_off = vp_modern_get_queue_notify_off(mdev, i);
vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
vp_vdpa->vring[i].notify = mdev->notify_base +
notify_off * mdev->notify_offset_multiplier;
}
vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
ret = vdpa_register_device(&vp_vdpa->vdpa, vp_vdpa->queues);
if (ret) {
dev_err(&pdev->dev, "Failed to register to vdpa bus\n");
goto err;
}
return 0;
err:
put_device(&vp_vdpa->vdpa.dev);
return ret;
}
static void vp_vdpa_remove(struct pci_dev *pdev)
{
struct vp_vdpa *vp_vdpa = pci_get_drvdata(pdev);
vdpa_unregister_device(&vp_vdpa->vdpa);
vp_modern_remove(&vp_vdpa->mdev);
}
static struct pci_driver vp_vdpa_driver = {
.name = "vp-vdpa",
.id_table = NULL, /* only dynamic ids */
.probe = vp_vdpa_probe,
.remove = vp_vdpa_remove,
};
module_pci_driver(vp_vdpa_driver);
MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
MODULE_DESCRIPTION("vp-vdpa");
MODULE_LICENSE("GPL");
MODULE_VERSION("1");