virtio-pci: introduce legacy device module

Split common codes from virtio-pci-legacy so vDPA driver can reuse it
later.

Signed-off-by: Wu Zongyong <wuzongyong@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/71605acde5e97fcb2760a6973e406279fb1bbd33.1635493219.git.wuzongyong@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Wu Zongyong 2021-10-29 17:14:42 +08:00 committed by Michael S. Tsirkin
parent 0989c41bed
commit d89c8169bd
7 changed files with 310 additions and 83 deletions

View File

@ -20,6 +20,15 @@ config VIRTIO_PCI_LIB
PCI device with possible vendor specific extensions. Any
module that selects this module must depend on PCI.
config VIRTIO_PCI_LIB_LEGACY
tristate
help
Legacy PCI device (Virtio PCI Card 0.9.x Draft and older device)
implementation.
This module implements the basic probe and control for devices
which are based on legacy PCI device. Any module that selects this
module must depend on PCI.
menuconfig VIRTIO_MENU
bool "Virtio drivers"
default y
@ -43,6 +52,7 @@ config VIRTIO_PCI_LEGACY
bool "Support for legacy virtio draft 0.9.X and older devices"
default y
depends on VIRTIO_PCI
select VIRTIO_PCI_LIB_LEGACY
help
Virtio PCI Card 0.9.X Draft (circa 2014) and older device support.

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@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o
obj-$(CONFIG_VIRTIO_PCI_LIB) += virtio_pci_modern_dev.o
obj-$(CONFIG_VIRTIO_PCI_LIB_LEGACY) += virtio_pci_legacy_dev.o
obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o
obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o
virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o

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@ -549,6 +549,8 @@ static int virtio_pci_probe(struct pci_dev *pci_dev,
pci_set_master(pci_dev);
vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false;
rc = register_virtio_device(&vp_dev->vdev);
reg_dev = vp_dev;
if (rc)
@ -557,10 +559,10 @@ static int virtio_pci_probe(struct pci_dev *pci_dev,
return 0;
err_register:
if (vp_dev->ioaddr)
virtio_pci_legacy_remove(vp_dev);
if (vp_dev->is_legacy)
virtio_pci_legacy_remove(vp_dev);
else
virtio_pci_modern_remove(vp_dev);
virtio_pci_modern_remove(vp_dev);
err_probe:
pci_disable_device(pci_dev);
err_enable_device:
@ -587,7 +589,7 @@ static void virtio_pci_remove(struct pci_dev *pci_dev)
unregister_virtio_device(&vp_dev->vdev);
if (vp_dev->ioaddr)
if (vp_dev->is_legacy)
virtio_pci_legacy_remove(vp_dev);
else
virtio_pci_modern_remove(vp_dev);

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@ -25,6 +25,7 @@
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/virtio_pci.h>
#include <linux/virtio_pci_legacy.h>
#include <linux/virtio_pci_modern.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>
@ -44,16 +45,14 @@ struct virtio_pci_vq_info {
struct virtio_pci_device {
struct virtio_device vdev;
struct pci_dev *pci_dev;
struct virtio_pci_legacy_device ldev;
struct virtio_pci_modern_device mdev;
/* In legacy mode, these two point to within ->legacy. */
bool is_legacy;
/* Where to read and clear interrupt */
u8 __iomem *isr;
/* Legacy only field */
/* the IO mapping for the PCI config space */
void __iomem *ioaddr;
/* a list of queues so we can dispatch IRQs */
spinlock_t lock;
struct list_head virtqueues;

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@ -14,6 +14,7 @@
* Michael S. Tsirkin <mst@redhat.com>
*/
#include "linux/virtio_pci_legacy.h"
#include "virtio_pci_common.h"
/* virtio config->get_features() implementation */
@ -23,7 +24,7 @@ static u64 vp_get_features(struct virtio_device *vdev)
/* When someone needs more than 32 feature bits, we'll need to
* steal a bit to indicate that the rest are somewhere else. */
return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
return vp_legacy_get_features(&vp_dev->ldev);
}
/* virtio config->finalize_features() implementation */
@ -38,7 +39,7 @@ static int vp_finalize_features(struct virtio_device *vdev)
BUG_ON((u32)vdev->features != vdev->features);
/* We only support 32 feature bits. */
iowrite32(vdev->features, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
vp_legacy_set_features(&vp_dev->ldev, vdev->features);
return 0;
}
@ -48,7 +49,7 @@ static void vp_get(struct virtio_device *vdev, unsigned offset,
void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
void __iomem *ioaddr = vp_dev->ioaddr +
void __iomem *ioaddr = vp_dev->ldev.ioaddr +
VIRTIO_PCI_CONFIG_OFF(vp_dev->msix_enabled) +
offset;
u8 *ptr = buf;
@ -64,7 +65,7 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
const void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
void __iomem *ioaddr = vp_dev->ioaddr +
void __iomem *ioaddr = vp_dev->ldev.ioaddr +
VIRTIO_PCI_CONFIG_OFF(vp_dev->msix_enabled) +
offset;
const u8 *ptr = buf;
@ -78,7 +79,7 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
static u8 vp_get_status(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
return vp_legacy_get_status(&vp_dev->ldev);
}
static void vp_set_status(struct virtio_device *vdev, u8 status)
@ -86,28 +87,24 @@ static void vp_set_status(struct virtio_device *vdev, u8 status)
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* We should never be setting status to 0. */
BUG_ON(status == 0);
iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
vp_legacy_set_status(&vp_dev->ldev, status);
}
static void vp_reset(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* 0 status means a reset. */
iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
vp_legacy_set_status(&vp_dev->ldev, 0);
/* Flush out the status write, and flush in device writes,
* including MSi-X interrupts, if any. */
ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
vp_legacy_get_status(&vp_dev->ldev);
/* Flush pending VQ/configuration callbacks. */
vp_synchronize_vectors(vdev);
}
static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
{
/* Setup the vector used for configuration events */
iowrite16(vector, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
/* Verify we had enough resources to assign the vector */
/* Will also flush the write out to device */
return ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
return vp_legacy_config_vector(&vp_dev->ldev, vector);
}
static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
@ -123,12 +120,9 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
int err;
u64 q_pfn;
/* Select the queue we're interested in */
iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
/* Check if queue is either not available or already active. */
num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
num = vp_legacy_get_queue_size(&vp_dev->ldev, index);
if (!num || vp_legacy_get_queue_enable(&vp_dev->ldev, index))
return ERR_PTR(-ENOENT);
info->msix_vector = msix_vec;
@ -151,13 +145,12 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
}
/* activate the queue */
iowrite32(q_pfn, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
vp_legacy_set_queue_address(&vp_dev->ldev, index, q_pfn);
vq->priv = (void __force *)vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
vq->priv = (void __force *)vp_dev->ldev.ioaddr + VIRTIO_PCI_QUEUE_NOTIFY;
if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
msix_vec = vp_legacy_queue_vector(&vp_dev->ldev, index, msix_vec);
if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
err = -EBUSY;
goto out_deactivate;
@ -167,7 +160,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
return vq;
out_deactivate:
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
vp_legacy_set_queue_address(&vp_dev->ldev, index, 0);
out_del_vq:
vring_del_virtqueue(vq);
return ERR_PTR(err);
@ -178,17 +171,15 @@ static void del_vq(struct virtio_pci_vq_info *info)
struct virtqueue *vq = info->vq;
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
if (vp_dev->msix_enabled) {
iowrite16(VIRTIO_MSI_NO_VECTOR,
vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
vp_legacy_queue_vector(&vp_dev->ldev, vq->index,
VIRTIO_MSI_NO_VECTOR);
/* Flush the write out to device */
ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
ioread8(vp_dev->ldev.ioaddr + VIRTIO_PCI_ISR);
}
/* Select and deactivate the queue */
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
vp_legacy_set_queue_address(&vp_dev->ldev, vq->index, 0);
vring_del_virtqueue(vq);
}
@ -211,51 +202,18 @@ static const struct virtio_config_ops virtio_pci_config_ops = {
/* the PCI probing function */
int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)
{
struct virtio_pci_legacy_device *ldev = &vp_dev->ldev;
struct pci_dev *pci_dev = vp_dev->pci_dev;
int rc;
/* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
return -ENODEV;
ldev->pci_dev = pci_dev;
if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
return -ENODEV;
}
rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64));
if (rc) {
rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32));
} else {
/*
* The virtio ring base address is expressed as a 32-bit PFN,
* with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT.
*/
dma_set_coherent_mask(&pci_dev->dev,
DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT));
}
if (rc)
dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
rc = pci_request_region(pci_dev, 0, "virtio-pci-legacy");
rc = vp_legacy_probe(ldev);
if (rc)
return rc;
rc = -ENOMEM;
vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
if (!vp_dev->ioaddr)
goto err_iomap;
vp_dev->isr = vp_dev->ioaddr + VIRTIO_PCI_ISR;
/* we use the subsystem vendor/device id as the virtio vendor/device
* id. this allows us to use the same PCI vendor/device id for all
* virtio devices and to identify the particular virtio driver by
* the subsystem ids */
vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
vp_dev->vdev.id.device = pci_dev->subsystem_device;
vp_dev->isr = ldev->isr;
vp_dev->vdev.id = ldev->id;
vp_dev->vdev.config = &virtio_pci_config_ops;
@ -264,16 +222,11 @@ int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)
vp_dev->del_vq = del_vq;
return 0;
err_iomap:
pci_release_region(pci_dev, 0);
return rc;
}
void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev)
{
struct pci_dev *pci_dev = vp_dev->pci_dev;
struct virtio_pci_legacy_device *ldev = &vp_dev->ldev;
pci_iounmap(pci_dev, vp_dev->ioaddr);
pci_release_region(pci_dev, 0);
vp_legacy_remove(ldev);
}

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@ -0,0 +1,220 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include "linux/virtio_pci.h"
#include <linux/virtio_pci_legacy.h>
#include <linux/module.h>
#include <linux/pci.h>
/*
* vp_legacy_probe: probe the legacy virtio pci device, note that the
* caller is required to enable PCI device before calling this function.
* @ldev: the legacy virtio-pci device
*
* Return 0 on succeed otherwise fail
*/
int vp_legacy_probe(struct virtio_pci_legacy_device *ldev)
{
struct pci_dev *pci_dev = ldev->pci_dev;
int rc;
/* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
return -ENODEV;
if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION)
return -ENODEV;
rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64));
if (rc) {
rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32));
} else {
/*
* The virtio ring base address is expressed as a 32-bit PFN,
* with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT.
*/
dma_set_coherent_mask(&pci_dev->dev,
DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT));
}
if (rc)
dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
rc = pci_request_region(pci_dev, 0, "virtio-pci-legacy");
if (rc)
return rc;
ldev->ioaddr = pci_iomap(pci_dev, 0, 0);
if (!ldev->ioaddr)
goto err_iomap;
ldev->isr = ldev->ioaddr + VIRTIO_PCI_ISR;
ldev->id.vendor = pci_dev->subsystem_vendor;
ldev->id.device = pci_dev->subsystem_device;
return 0;
err_iomap:
pci_release_region(pci_dev, 0);
return rc;
}
EXPORT_SYMBOL_GPL(vp_legacy_probe);
/*
* vp_legacy_probe: remove and cleanup the legacy virtio pci device
* @ldev: the legacy virtio-pci device
*/
void vp_legacy_remove(struct virtio_pci_legacy_device *ldev)
{
struct pci_dev *pci_dev = ldev->pci_dev;
pci_iounmap(pci_dev, ldev->ioaddr);
pci_release_region(pci_dev, 0);
}
EXPORT_SYMBOL_GPL(vp_legacy_remove);
/*
* vp_legacy_get_features - get features from device
* @ldev: the legacy virtio-pci device
*
* Returns the features read from the device
*/
u64 vp_legacy_get_features(struct virtio_pci_legacy_device *ldev)
{
return ioread32(ldev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
}
EXPORT_SYMBOL_GPL(vp_legacy_get_features);
/*
* vp_legacy_get_driver_features - get driver features from device
* @ldev: the legacy virtio-pci device
*
* Returns the driver features read from the device
*/
u64 vp_legacy_get_driver_features(struct virtio_pci_legacy_device *ldev)
{
return ioread32(ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
}
EXPORT_SYMBOL_GPL(vp_legacy_get_driver_features);
/*
* vp_legacy_set_features - set features to device
* @ldev: the legacy virtio-pci device
* @features: the features set to device
*/
void vp_legacy_set_features(struct virtio_pci_legacy_device *ldev,
u32 features)
{
iowrite32(features, ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
}
EXPORT_SYMBOL_GPL(vp_legacy_set_features);
/*
* vp_legacy_get_status - get the device status
* @ldev: the legacy virtio-pci device
*
* Returns the status read from device
*/
u8 vp_legacy_get_status(struct virtio_pci_legacy_device *ldev)
{
return ioread8(ldev->ioaddr + VIRTIO_PCI_STATUS);
}
EXPORT_SYMBOL_GPL(vp_legacy_get_status);
/*
* vp_legacy_set_status - set status to device
* @ldev: the legacy virtio-pci device
* @status: the status set to device
*/
void vp_legacy_set_status(struct virtio_pci_legacy_device *ldev,
u8 status)
{
iowrite8(status, ldev->ioaddr + VIRTIO_PCI_STATUS);
}
EXPORT_SYMBOL_GPL(vp_legacy_set_status);
/*
* vp_legacy_queue_vector - set the MSIX vector for a specific virtqueue
* @ldev: the legacy virtio-pci device
* @index: queue index
* @vector: the config vector
*
* Returns the config vector read from the device
*/
u16 vp_legacy_queue_vector(struct virtio_pci_legacy_device *ldev,
u16 index, u16 vector)
{
iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
/* Flush the write out to device */
return ioread16(ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
}
EXPORT_SYMBOL_GPL(vp_legacy_queue_vector);
/*
* vp_legacy_config_vector - set the vector for config interrupt
* @ldev: the legacy virtio-pci device
* @vector: the config vector
*
* Returns the config vector read from the device
*/
u16 vp_legacy_config_vector(struct virtio_pci_legacy_device *ldev,
u16 vector)
{
/* Setup the vector used for configuration events */
iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
/* Verify we had enough resources to assign the vector */
/* Will also flush the write out to device */
return ioread16(ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
}
EXPORT_SYMBOL_GPL(vp_legacy_config_vector);
/*
* vp_legacy_set_queue_address - set the virtqueue address
* @ldev: the legacy virtio-pci device
* @index: the queue index
* @queue_pfn: pfn of the virtqueue
*/
void vp_legacy_set_queue_address(struct virtio_pci_legacy_device *ldev,
u16 index, u32 queue_pfn)
{
iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
iowrite32(queue_pfn, ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
}
EXPORT_SYMBOL_GPL(vp_legacy_set_queue_address);
/*
* vp_legacy_get_queue_enable - enable a virtqueue
* @ldev: the legacy virtio-pci device
* @index: the queue index
*
* Returns whether a virtqueue is enabled or not
*/
bool vp_legacy_get_queue_enable(struct virtio_pci_legacy_device *ldev,
u16 index)
{
iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
return ioread32(ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
}
EXPORT_SYMBOL_GPL(vp_legacy_get_queue_enable);
/*
* vp_legacy_get_queue_size - get size for a virtqueue
* @ldev: the legacy virtio-pci device
* @index: the queue index
*
* Returns the size of the virtqueue
*/
u16 vp_legacy_get_queue_size(struct virtio_pci_legacy_device *ldev,
u16 index)
{
iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
return ioread16(ldev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
}
EXPORT_SYMBOL_GPL(vp_legacy_get_queue_size);
MODULE_VERSION("0.1");
MODULE_DESCRIPTION("Legacy Virtio PCI Device");
MODULE_AUTHOR("Wu Zongyong <wuzongyong@linux.alibaba.com>");
MODULE_LICENSE("GPL");

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@ -0,0 +1,42 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_VIRTIO_PCI_LEGACY_H
#define _LINUX_VIRTIO_PCI_LEGACY_H
#include "linux/mod_devicetable.h"
#include <linux/pci.h>
#include <linux/virtio_pci.h>
struct virtio_pci_legacy_device {
struct pci_dev *pci_dev;
/* Where to read and clear interrupt */
u8 __iomem *isr;
/* The IO mapping for the PCI config space (legacy mode only) */
void __iomem *ioaddr;
struct virtio_device_id id;
};
u64 vp_legacy_get_features(struct virtio_pci_legacy_device *ldev);
u64 vp_legacy_get_driver_features(struct virtio_pci_legacy_device *ldev);
void vp_legacy_set_features(struct virtio_pci_legacy_device *ldev,
u32 features);
u8 vp_legacy_get_status(struct virtio_pci_legacy_device *ldev);
void vp_legacy_set_status(struct virtio_pci_legacy_device *ldev,
u8 status);
u16 vp_legacy_queue_vector(struct virtio_pci_legacy_device *ldev,
u16 idx, u16 vector);
u16 vp_legacy_config_vector(struct virtio_pci_legacy_device *ldev,
u16 vector);
void vp_legacy_set_queue_address(struct virtio_pci_legacy_device *ldev,
u16 index, u32 queue_pfn);
bool vp_legacy_get_queue_enable(struct virtio_pci_legacy_device *ldev,
u16 idx);
void vp_legacy_set_queue_size(struct virtio_pci_legacy_device *ldev,
u16 idx, u16 size);
u16 vp_legacy_get_queue_size(struct virtio_pci_legacy_device *ldev,
u16 idx);
int vp_legacy_probe(struct virtio_pci_legacy_device *ldev);
void vp_legacy_remove(struct virtio_pci_legacy_device *ldev);
#endif