// 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 <[email protected]>
*
* 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>
#include <uapi/linux/vdpa.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;
resource_size_t notify_pa;
int irq;
};
struct vp_vdpa {
struct vdpa_device vdpa;
struct virtio_pci_modern_device *mdev;
struct vp_vring *vring;
struct vdpa_callback config_cb;
u64 device_features;
char msix_name[VP_VDPA_NAME_SIZE];
int config_irq;
int queues;
int vectors;
};
struct vp_vdpa_mgmtdev {
struct vdpa_mgmt_dev mgtdev;
struct virtio_pci_modern_device *mdev;
struct vp_vdpa *vp_vdpa;
};
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 struct virtio_pci_modern_device *vp_vdpa_to_mdev(struct vp_vdpa *vp_vdpa)
{
return vp_vdpa->mdev;
}
static u64 vp_vdpa_get_device_features(struct vdpa_device *vdpa)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
return vp_vdpa->device_features;
}
static int vp_vdpa_set_driver_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 u64 vp_vdpa_get_driver_features(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return vp_modern_get_driver_features(mdev);
}
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 int vp_vdpa_get_vq_irq(struct vdpa_device *vdpa, u16 idx)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
int irq = vp_vdpa->vring[idx].irq;
if (irq == VIRTIO_MSI_NO_VECTOR)
return -EINVAL;
return irq;
}
static void vp_vdpa_free_irq(struct vp_vdpa *vp_vdpa)
{
struct virtio_pci_modern_device *mdev = vp_vdpa_to_mdev(vp_vdpa);
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_to_mdev(vp_vdpa);
struct pci_dev *pdev = mdev->pci_dev;
int i, ret, irq;
int queues = vp_vdpa->queues;
int vectors = 1;
int msix_vec = 0;
for (i = 0; i < queues; i++) {
if (vp_vdpa->vring[i].cb.callback)
vectors++;
}
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++) {
if (!vp_vdpa->vring[i].cb.callback)
continue;
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, msix_vec);
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, msix_vec);
vp_vdpa->vring[i].irq = irq;
msix_vec++;
}
snprintf(vp_vdpa->msix_name, VP_VDPA_NAME_SIZE, "vp-vdpa[%s]-config\n",
pci_name(pdev));
irq = pci_irq_vector(pdev, msix_vec);
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 config: %d\n", ret);
goto err;
}
vp_modern_config_vector(mdev, msix_vec);
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_to_mdev(vp_vdpa);
u8 s = vp_vdpa_get_status(vdpa);
if (status & VIRTIO_CONFIG_S_DRIVER_OK &&
!(s & VIRTIO_CONFIG_S_DRIVER_OK)) {
if (vp_vdpa_request_irq(vp_vdpa)) {
WARN_ON(1);
return;
}
}
vp_modern_set_status(mdev, status);
}
static int vp_vdpa_reset(struct vdpa_device *vdpa)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
struct virtio_pci_modern_device *mdev = vp_vdpa_to_mdev(vp_vdpa);
u8 s = vp_vdpa_get_status(vdpa);
vp_modern_set_status(mdev, 0);
if (s & VIRTIO_CONFIG_S_DRIVER_OK)
vp_vdpa_free_irq(vp_vdpa);
return 0;
}
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_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_packed(struct vdpa_device *vdpa,
const struct vdpa_vq_state *state)
{
const struct vdpa_vq_state_packed *packed = &state->packed;
if (packed->last_avail_counter == 1 &&
packed->last_avail_idx == 0 &&
packed->last_used_counter == 1 &&
packed->last_used_idx == 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_modern_device *mdev = vdpa_to_mdev(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_modern_get_status(mdev) & VIRTIO_CONFIG_S_FEATURES_OK) &&
!vp_modern_get_queue_enable(mdev, qid)) {
if (vp_modern_get_driver_features(mdev) &
BIT_ULL(VIRTIO_F_RING_PACKED))
return vp_vdpa_set_vq_state_packed(vdpa, state);
else
return vp_vdpa_set_vq_state_split(vdpa, state);
}
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 u16 vp_vdpa_get_vq_size(struct vdpa_device *vdpa, u16 qid)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return vp_modern_get_queue_size(mdev, qid);
}
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 size_t vp_vdpa_get_config_size(struct vdpa_device *vdpa)
{
struct virtio_pci_modern_device *mdev = vdpa_to_mdev(vdpa);
return mdev->device_len;
}
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_to_mdev(vp_vdpa);
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_to_mdev(vp_vdpa);
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 struct vdpa_notification_area
vp_vdpa_get_vq_notification(struct vdpa_device *vdpa, u16 qid)
{
struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
struct virtio_pci_modern_device *mdev = vp_vdpa_to_mdev(vp_vdpa);
struct vdpa_notification_area notify;
notify.addr = vp_vdpa->vring[qid].notify_pa;
notify.size = mdev->notify_offset_multiplier;
return notify;
}
static const struct vdpa_config_ops vp_vdpa_ops = {
.get_device_features = vp_vdpa_get_device_features,
.set_driver_features = vp_vdpa_set_driver_features,
.get_driver_features = vp_vdpa_get_driver_features,
.get_status = vp_vdpa_get_status,
.set_status = vp_vdpa_set_status,
.reset = vp_vdpa_reset,
.get_vq_num_max = vp_vdpa_get_vq_num_max,
.get_vq_state = vp_vdpa_get_vq_state,
.get_vq_notification = vp_vdpa_get_vq_notification,
.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,
.get_vq_size = vp_vdpa_get_vq_size,
.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_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,
};
static void vp_vdpa_free_irq_vectors(void *data)
{
pci_free_irq_vectors(data);
}
static int vp_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
const struct vdpa_dev_set_config *add_config)
{
struct vp_vdpa_mgmtdev *vp_vdpa_mgtdev =
container_of(v_mdev, struct vp_vdpa_mgmtdev, mgtdev);
struct virtio_pci_modern_device *mdev = vp_vdpa_mgtdev->mdev;
struct pci_dev *pdev = mdev->pci_dev;
struct device *dev = &pdev->dev;
struct vp_vdpa *vp_vdpa = NULL;
u64 device_features;
int ret, i;
vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
dev, &vp_vdpa_ops, 1, 1, name, false);
if (IS_ERR(vp_vdpa)) {
dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");
return PTR_ERR(vp_vdpa);
}
vp_vdpa_mgtdev->vp_vdpa = vp_vdpa;
vp_vdpa->vdpa.dma_dev = &pdev->dev;
vp_vdpa->queues = vp_modern_get_num_queues(mdev);
vp_vdpa->mdev = mdev;
device_features = vp_modern_get_features(mdev);
if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
if (add_config->device_features & ~device_features) {
ret = -EINVAL;
dev_err(&pdev->dev, "Try to provision features "
"that are not supported by the device: "
"device_features 0x%llx provisioned 0x%llx\n",
device_features, add_config->device_features);
goto err;
}
device_features = add_config->device_features;
}
vp_vdpa->device_features = device_features;
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++) {
vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
vp_vdpa->vring[i].notify =
vp_modern_map_vq_notify(mdev, i,
&vp_vdpa->vring[i].notify_pa);
if (!vp_vdpa->vring[i].notify) {
ret = -EINVAL;
dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
goto err;
}
}
vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
vp_vdpa->vdpa.mdev = &vp_vdpa_mgtdev->mgtdev;
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_dev_del(struct vdpa_mgmt_dev *v_mdev,
struct vdpa_device *dev)
{
struct vp_vdpa_mgmtdev *vp_vdpa_mgtdev =
container_of(v_mdev, struct vp_vdpa_mgmtdev, mgtdev);
struct vp_vdpa *vp_vdpa = vp_vdpa_mgtdev->vp_vdpa;
_vdpa_unregister_device(&vp_vdpa->vdpa);
vp_vdpa_mgtdev->vp_vdpa = NULL;
}
static const struct vdpa_mgmtdev_ops vp_vdpa_mdev_ops = {
.dev_add = vp_vdpa_dev_add,
.dev_del = vp_vdpa_dev_del,
};
static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct vp_vdpa_mgmtdev *vp_vdpa_mgtdev = NULL;
struct vdpa_mgmt_dev *mgtdev;
struct device *dev = &pdev->dev;
struct virtio_pci_modern_device *mdev = NULL;
struct virtio_device_id *mdev_id = NULL;
int err;
vp_vdpa_mgtdev = kzalloc(sizeof(*vp_vdpa_mgtdev), GFP_KERNEL);
if (!vp_vdpa_mgtdev)
return -ENOMEM;
mgtdev = &vp_vdpa_mgtdev->mgtdev;
mgtdev->ops = &vp_vdpa_mdev_ops;
mgtdev->device = dev;
mdev = kzalloc(sizeof(struct virtio_pci_modern_device), GFP_KERNEL);
if (!mdev) {
err = -ENOMEM;
goto mdev_err;
}
mdev_id = kzalloc(sizeof(struct virtio_device_id), GFP_KERNEL);
if (!mdev_id) {
err = -ENOMEM;
goto mdev_id_err;
}
vp_vdpa_mgtdev->mdev = mdev;
mdev->pci_dev = pdev;
err = pcim_enable_device(pdev);
if (err) {
goto probe_err;
}
err = vp_modern_probe(mdev);
if (err) {
dev_err(&pdev->dev, "Failed to probe modern PCI device\n");
goto probe_err;
}
mdev_id->device = mdev->id.device;
mdev_id->vendor = mdev->id.vendor;
mgtdev->id_table = mdev_id;
mgtdev->max_supported_vqs = vp_modern_get_num_queues(mdev);
mgtdev->supported_features = vp_modern_get_features(mdev);
mgtdev->config_attr_mask = (1 << VDPA_ATTR_DEV_FEATURES);
pci_set_master(pdev);
pci_set_drvdata(pdev, vp_vdpa_mgtdev);
err = vdpa_mgmtdev_register(mgtdev);
if (err) {
dev_err(&pdev->dev, "Failed to register vdpa mgmtdev device\n");
goto register_err;
}
return 0;
register_err:
vp_modern_remove(vp_vdpa_mgtdev->mdev);
probe_err:
kfree(mdev_id);
mdev_id_err:
kfree(mdev);
mdev_err:
kfree(vp_vdpa_mgtdev);
return err;
}
static void vp_vdpa_remove(struct pci_dev *pdev)
{
struct vp_vdpa_mgmtdev *vp_vdpa_mgtdev = pci_get_drvdata(pdev);
struct virtio_pci_modern_device *mdev = NULL;
mdev = vp_vdpa_mgtdev->mdev;
vdpa_mgmtdev_unregister(&vp_vdpa_mgtdev->mgtdev);
vp_modern_remove(mdev);
kfree(vp_vdpa_mgtdev->mgtdev.id_table);
kfree(mdev);
kfree(vp_vdpa_mgtdev);
}
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 <[email protected]>");
MODULE_DESCRIPTION("vp-vdpa");
MODULE_LICENSE("GPL");
MODULE_VERSION("1");