[PATCH V2 16/19] virtio-pci: introduce modern device module

From: Jason Wang
Date: Thu Dec 03 2020 - 23:06:37 EST

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/virtio/Kconfig | 10 +-
drivers/virtio/Makefile | 1 +
drivers/virtio/virtio_pci_common.h | 27 +-
drivers/virtio/virtio_pci_modern.c | 617 -------------------------
drivers/virtio/virtio_pci_modern_dev.c | 599 ++++++++++++++++++++++++
include/linux/virtio_pci_modern.h | 111 +++++
6 files changed, 721 insertions(+), 644 deletions(-)
create mode 100644 drivers/virtio/virtio_pci_modern_dev.c
create mode 100644 include/linux/virtio_pci_modern.h

diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index 7b41130d3f35..d1a6bd2a975f 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -12,6 +12,14 @@ config ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
This option is selected if the architecture may need to enforce
VIRTIO_F_ACCESS_PLATFORM

+config VIRTIO_PCI_MODERN
+ tristate "Modern Virtio PCI Device"
+ depends on PCI
+ help
+ Modern PCI device implementation. This module implement the
+ basic probe and control for devices which is based on modern
+ PCI device with possible vendor specific extensions.
+
menuconfig VIRTIO_MENU
bool "Virtio drivers"
default y
@@ -20,7 +28,7 @@ if VIRTIO_MENU

config VIRTIO_PCI
tristate "PCI driver for virtio devices"
- depends on PCI
+ depends on VIRTIO_PCI_MODERN
select VIRTIO
help
This driver provides support for virtio based paravirtual device
diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile
index 591e6f72aa54..f097578aaa8f 100644
--- a/drivers/virtio/Makefile
+++ b/drivers/virtio/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o
+obj-$(CONFIG_VIRTIO_PCI_MODERN) += virtio_pci_modern_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
diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h
index f35ff5b6b467..beec047a8f8d 100644
--- a/drivers/virtio/virtio_pci_common.h
+++ b/drivers/virtio/virtio_pci_common.h
@@ -25,6 +25,7 @@
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/virtio_pci.h>
+#include <linux/virtio_pci_modern.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>

@@ -39,32 +40,6 @@ struct virtio_pci_vq_info {
unsigned msix_vector;
};

-struct virtio_pci_modern_device {
- struct pci_dev *pci_dev;
-
- struct virtio_pci_common_cfg __iomem *common;
- /* Device-specific data (non-legacy mode) */
- void __iomem *device;
- /* Base of vq notifications (non-legacy mode). */
- void __iomem *notify_base;
- /* Where to read and clear interrupt */
- u8 __iomem *isr;
-
- /* So we can sanity-check accesses. */
- size_t notify_len;
- size_t device_len;
-
- /* Capability for when we need to map notifications per-vq. */
- int notify_map_cap;
-
- /* Multiply queue_notify_off by this value. (non-legacy mode). */
- u32 notify_offset_multiplier;
-
- int modern_bars;
-
- struct virtio_device_id id;
-};
-
/* Our device structure */
struct virtio_pci_device {
struct virtio_device vdev;
diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index a5e3a5e40323..fbd4ebc00eb6 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -19,158 +19,6 @@
#define VIRTIO_RING_NO_LEGACY
#include "virtio_pci_common.h"

-/*
- * Type-safe wrappers for io accesses.
- * Use these to enforce at compile time the following spec requirement:
- *
- * The driver MUST access each field using the “natural” access
- * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
- * for 16-bit fields and 8-bit accesses for 8-bit fields.
- */
-static inline u8 vp_ioread8(const u8 __iomem *addr)
-{
- return ioread8(addr);
-}
-static inline u16 vp_ioread16 (const __le16 __iomem *addr)
-{
- return ioread16(addr);
-}
-
-static inline u32 vp_ioread32(const __le32 __iomem *addr)
-{
- return ioread32(addr);
-}
-
-static inline void vp_iowrite8(u8 value, u8 __iomem *addr)
-{
- iowrite8(value, addr);
-}
-
-static inline void vp_iowrite16(u16 value, __le16 __iomem *addr)
-{
- iowrite16(value, addr);
-}
-
-static inline void vp_iowrite32(u32 value, __le32 __iomem *addr)
-{
- iowrite32(value, addr);
-}
-
-static void vp_iowrite64_twopart(u64 val,
- __le32 __iomem *lo, __le32 __iomem *hi)
-{
- vp_iowrite32((u32)val, lo);
- vp_iowrite32(val >> 32, hi);
-}
-
-/*
- * vp_modern_map_capability - map a part of virtio pci capability
- * @mdev: the modern virtio-pci device
- * @off: offset of the capability
- * @minlen: minimal length of the capability
- * @align: align requirement
- * @start: start from the capability
- * @size: map size
- * @len: the length that is actually mapped
- *
- * Returns the io address of for the part of the capability
- */
-void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
- size_t minlen,
- u32 align,
- u32 start, u32 size,
- size_t *len)
-{
- struct pci_dev *dev = mdev->pci_dev;
- u8 bar;
- u32 offset, length;
- void __iomem *p;
-
- pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
- bar),
- &bar);
- pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
- &offset);
- pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
- &length);
-
- if (length <= start) {
- dev_err(&dev->dev,
- "virtio_pci: bad capability len %u (>%u expected)\n",
- length, start);
- return NULL;
- }
-
- if (length - start < minlen) {
- dev_err(&dev->dev,
- "virtio_pci: bad capability len %u (>=%zu expected)\n",
- length, minlen);
- return NULL;
- }
-
- length -= start;
-
- if (start + offset < offset) {
- dev_err(&dev->dev,
- "virtio_pci: map wrap-around %u+%u\n",
- start, offset);
- return NULL;
- }
-
- offset += start;
-
- if (offset & (align - 1)) {
- dev_err(&dev->dev,
- "virtio_pci: offset %u not aligned to %u\n",
- offset, align);
- return NULL;
- }
-
- if (length > size)
- length = size;
-
- if (len)
- *len = length;
-
- if (minlen + offset < minlen ||
- minlen + offset > pci_resource_len(dev, bar)) {
- dev_err(&dev->dev,
- "virtio_pci: map virtio %zu@%u "
- "out of range on bar %i length %lu\n",
- minlen, offset,
- bar, (unsigned long)pci_resource_len(dev, bar));
- return NULL;
- }
-
- p = pci_iomap_range(dev, bar, offset, length);
- if (!p)
- dev_err(&dev->dev,
- "virtio_pci: unable to map virtio %u@%u on bar %i\n",
- length, offset, bar);
- return p;
-}
-
-/*
- * vp_modern_get_features - get features from device
- * @mdev: the modern virtio-pci device
- *
- * Returns the features read from the device
- */
-static u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- u64 features;
-
- vp_iowrite32(0, &cfg->device_feature_select);
- features = vp_ioread32(&cfg->device_feature);
- vp_iowrite32(1, &cfg->device_feature_select);
- features |= ((u64)vp_ioread32(&cfg->device_feature) << 32);
-
- return features;
-}
-
-/* virtio config->get_features() implementation */
static u64 vp_get_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -188,149 +36,6 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features)
__virtio_set_bit(vdev, VIRTIO_F_SR_IOV);
}

-/*
- * vp_modern_set_features - set features to device
- * @mdev: the modern virtio-pci device
- * @features: the features set to device
- */
-static void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
- u64 features)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- vp_iowrite32(0, &cfg->guest_feature_select);
- vp_iowrite32((u32)features, &cfg->guest_feature);
- vp_iowrite32(1, &cfg->guest_feature_select);
- vp_iowrite32(features >> 32, &cfg->guest_feature);
-}
-
-/*
- * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
- * @mdev: the modern virtio-pci device
- * @index: queue index
- * @vector: the config vector
- *
- * Returns the config vector read from the device
- */
-static u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
- u16 index, u16 vector)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- vp_iowrite16(index, &cfg->queue_select);
- vp_iowrite16(vector, &cfg->queue_msix_vector);
- /* Flush the write out to device */
- return vp_ioread16(&cfg->queue_msix_vector);
-}
-
-/*
- * vp_modern_queue_address - set the virtqueue address
- * @mdev: the modern virtio-pci device
- * @index: the queue index
- * @desc_addr: address of the descriptor area
- * @driver_addr: address of the driver area
- * @device_addr: address of the device area
- */
-static void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
- u16 index, u64 desc_addr, u64 driver_addr,
- u64 device_addr)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- vp_iowrite16(index, &cfg->queue_select);
-
- vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo,
- &cfg->queue_desc_hi);
- vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo,
- &cfg->queue_avail_hi);
- vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo,
- &cfg->queue_used_hi);
-}
-
-/*
- * vp_modern_set_queue_enable - enable a virtqueue
- * @mdev: the modern virtio-pci device
- * @index: the queue index
- * @enable: whether the virtqueue is enable or not
- */
-static void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
- u16 index, bool enable)
-{
- vp_iowrite16(index, &mdev->common->queue_select);
- vp_iowrite16(enable, &mdev->common->queue_enable);
-}
-
-/*
- * vp_modern_get_queue_enable - enable a virtqueue
- * @mdev: the modern virtio-pci device
- * @index: the queue index
- *
- * Returns whether a virtqueue is enabled or not
- */
-static bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
- u16 index)
-{
- vp_iowrite16(index, &mdev->common->queue_select);
-
- return vp_ioread16(&mdev->common->queue_enable);
-}
-
-/*
- * vp_modern_set_queue_size - set size for a virtqueue
- * @mdev: the modern virtio-pci device
- * @index: the queue index
- * @size: the size of the virtqueue
- */
-static void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
- u16 index, u16 size)
-{
- vp_iowrite16(index, &mdev->common->queue_select);
- vp_iowrite16(size, &mdev->common->queue_size);
-
-}
-
-/*
- * vp_modern_get_queue_size - get size for a virtqueue
- * @mdev: the modern virtio-pci device
- * @index: the queue index
- *
- * Returns the size of the virtqueue
- */
-static u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
- u16 index)
-{
- vp_iowrite16(index, &mdev->common->queue_select);
-
- return vp_ioread16(&mdev->common->queue_size);
-
-}
-
-/*
- * vp_modern_get_num_queues - get the number of virtqueues
- * @mdev: the modern virtio-pci device
- *
- * Returns the number of virtqueues
- */
-static u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev)
-{
- return vp_ioread16(&mdev->common->num_queues);
-}
-
-/*
- * vp_modern_get_queue_notify_off - get notification offset for a virtqueue
- * @mdev: the modern virtio-pci device
- * @index: the queue index
- *
- * Returns the notification offset for a virtqueue
- */
-static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
- u16 index)
-{
- vp_iowrite16(index, &mdev->common->queue_select);
-
- return vp_ioread16(&mdev->common->queue_notify_off);
-}
-
/* virtio config->finalize_features() implementation */
static int vp_finalize_features(struct virtio_device *vdev)
{
@@ -429,19 +134,6 @@ static void vp_set(struct virtio_device *vdev, unsigned offset,
}
}

-/*
- * vp_modern_generation - get the device genreation
- * @mdev: the modern virtio-pci device
- *
- * Returns the genreation read from device
- */
-static u32 vp_modern_generation(struct virtio_pci_modern_device *mdev)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- return vp_ioread8(&cfg->config_generation);
-}
-
static u32 vp_generation(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -449,19 +141,6 @@ static u32 vp_generation(struct virtio_device *vdev)
return vp_modern_generation(&vp_dev->mdev);
}

-/*
- * vp_modern_get_status - get the device status
- * @mdev: the modern virtio-pci device
- *
- * Returns the status read from device
- */
-static u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- return vp_ioread8(&cfg->device_status);
-}
-
/* config->{get,set}_status() implementations */
static u8 vp_get_status(struct virtio_device *vdev)
{
@@ -470,19 +149,6 @@ static u8 vp_get_status(struct virtio_device *vdev)
return vp_modern_get_status(&vp_dev->mdev);
}

-/*
- * vp_modern_set_status - set status to device
- * @mdev: the modern virtio-pci device
- * @status: the status set to device
- */
-static void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
- u8 status)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- vp_iowrite8(status, &cfg->device_status);
-}
-
static void vp_set_status(struct virtio_device *vdev, u8 status)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
@@ -510,25 +176,6 @@ static void vp_reset(struct virtio_device *vdev)
vp_synchronize_vectors(vdev);
}

-/*
- * vp_modern_config_vector - set the vector for config interrupt
- * @mdev: the modern virtio-pci device
- * @vector: the config vector
- *
- * Returns the config vector read from the device
- */
-static u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev,
- u16 vector)
-{
- struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
-
- /* Setup the vector used for configuration events */
- vp_iowrite16(vector, &cfg->msix_config);
- /* Verify we had enough resources to assign the vector */
- /* Will also flush the write out to device */
- return vp_ioread16(&cfg->msix_config);
-}
-
static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
{
return vp_modern_config_vector(&vp_dev->mdev, vector);
@@ -789,253 +436,6 @@ static const struct virtio_config_ops virtio_pci_config_ops = {
.get_shm_region = vp_get_shm_region,
};

-/**
- * virtio_pci_find_capability - walk capabilities to find device info.
- * @dev: the pci device
- * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
- * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
- * @bars: the bitmask of BARs
- *
- * Returns offset of the capability, or 0.
- */
-static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
- u32 ioresource_types, int *bars)
-{
- int pos;
-
- for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
- pos > 0;
- pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
- u8 type, bar;
- pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
- cfg_type),
- &type);
- pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
- bar),
- &bar);
-
- /* Ignore structures with reserved BAR values */
- if (bar > 0x5)
- continue;
-
- if (type == cfg_type) {
- if (pci_resource_len(dev, bar) &&
- pci_resource_flags(dev, bar) & ioresource_types) {
- *bars |= (1 << bar);
- return pos;
- }
- }
- }
- return 0;
-}
-
-/* This is part of the ABI. Don't screw with it. */
-static inline void check_offsets(void)
-{
- /* Note: disk space was harmed in compilation of this function. */
- BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
- offsetof(struct virtio_pci_cap, cap_vndr));
- BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
- offsetof(struct virtio_pci_cap, cap_next));
- BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
- offsetof(struct virtio_pci_cap, cap_len));
- BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
- offsetof(struct virtio_pci_cap, cfg_type));
- BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
- offsetof(struct virtio_pci_cap, bar));
- BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
- offsetof(struct virtio_pci_cap, offset));
- BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
- offsetof(struct virtio_pci_cap, length));
- BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
- offsetof(struct virtio_pci_notify_cap,
- notify_off_multiplier));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
- offsetof(struct virtio_pci_common_cfg,
- device_feature_select));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
- offsetof(struct virtio_pci_common_cfg, device_feature));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
- offsetof(struct virtio_pci_common_cfg,
- guest_feature_select));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
- offsetof(struct virtio_pci_common_cfg, guest_feature));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
- offsetof(struct virtio_pci_common_cfg, msix_config));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
- offsetof(struct virtio_pci_common_cfg, num_queues));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
- offsetof(struct virtio_pci_common_cfg, device_status));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
- offsetof(struct virtio_pci_common_cfg, config_generation));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
- offsetof(struct virtio_pci_common_cfg, queue_select));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
- offsetof(struct virtio_pci_common_cfg, queue_size));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
- offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
- offsetof(struct virtio_pci_common_cfg, queue_enable));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
- offsetof(struct virtio_pci_common_cfg, queue_notify_off));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
- offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
- offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
- offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
- offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
- offsetof(struct virtio_pci_common_cfg, queue_used_lo));
- BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
- offsetof(struct virtio_pci_common_cfg, queue_used_hi));
-}
-
-/*
- * vp_modern_probe: probe the modern virtio pci device, note that the
- * caller is required to enable PCI device before calling this function.
- * @mdev: the modern virtio-pci device
- *
- * Return 0 on succeed otherwise fail
- */
-static int vp_modern_probe(struct virtio_pci_modern_device *mdev)
-{
- struct pci_dev *pci_dev = mdev->pci_dev;
- int err, common, isr, notify, device;
- u32 notify_length;
- u32 notify_offset;
-
- check_offsets();
-
- mdev->pci_dev = pci_dev;
-
- /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
- if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
- return -ENODEV;
-
- if (pci_dev->device < 0x1040) {
- /* Transitional devices: use the PCI subsystem device id as
- * virtio device id, same as legacy driver always did.
- */
- mdev->id.device = pci_dev->subsystem_device;
- } else {
- /* Modern devices: simply use PCI device id, but start from 0x1040. */
- mdev->id.device = pci_dev->device - 0x1040;
- }
- mdev->id.vendor = pci_dev->subsystem_vendor;
-
- /* check for a common config: if not, use legacy mode (bar 0). */
- common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
- IORESOURCE_IO | IORESOURCE_MEM,
- &mdev->modern_bars);
- if (!common) {
- dev_info(&pci_dev->dev,
- "virtio_pci: leaving for legacy driver\n");
- return -ENODEV;
- }
-
- /* If common is there, these should be too... */
- isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
- IORESOURCE_IO | IORESOURCE_MEM,
- &mdev->modern_bars);
- notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
- IORESOURCE_IO | IORESOURCE_MEM,
- &mdev->modern_bars);
- if (!isr || !notify) {
- dev_err(&pci_dev->dev,
- "virtio_pci: missing capabilities %i/%i/%i\n",
- common, isr, notify);
- return -EINVAL;
- }
-
- err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
- if (err)
- err = dma_set_mask_and_coherent(&pci_dev->dev,
- DMA_BIT_MASK(32));
- if (err)
- dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
-
- /* Device capability is only mandatory for devices that have
- * device-specific configuration.
- */
- device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
- IORESOURCE_IO | IORESOURCE_MEM,
- &mdev->modern_bars);
-
- err = pci_request_selected_regions(pci_dev, mdev->modern_bars,
- "virtio-pci-modern");
- if (err)
- return err;
-
- err = -EINVAL;
- mdev->common = vp_modern_map_capability(mdev, common,
- sizeof(struct virtio_pci_common_cfg), 4,
- 0, sizeof(struct virtio_pci_common_cfg),
- NULL);
- if (!mdev->common)
- goto err_map_common;
- mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1,
- 0, 1,
- NULL);
- if (!mdev->isr)
- goto err_map_isr;
-
- /* Read notify_off_multiplier from config space. */
- pci_read_config_dword(pci_dev,
- notify + offsetof(struct virtio_pci_notify_cap,
- notify_off_multiplier),
- &mdev->notify_offset_multiplier);
- /* Read notify length and offset from config space. */
- pci_read_config_dword(pci_dev,
- notify + offsetof(struct virtio_pci_notify_cap,
- cap.length),
- &notify_length);
-
- pci_read_config_dword(pci_dev,
- notify + offsetof(struct virtio_pci_notify_cap,
- cap.offset),
- &notify_offset);
-
- /* We don't know how many VQs we'll map, ahead of the time.
- * If notify length is small, map it all now.
- * Otherwise, map each VQ individually later.
- */
- if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
- mdev->notify_base = vp_modern_map_capability(mdev, notify,
- 2, 2,
- 0, notify_length,
- &mdev->notify_len);
- if (!mdev->notify_base)
- goto err_map_notify;
- } else {
- mdev->notify_map_cap = notify;
- }
-
- /* Again, we don't know how much we should map, but PAGE_SIZE
- * is more than enough for all existing devices.
- */
- if (device) {
- mdev->device = vp_modern_map_capability(mdev, device, 0, 4,
- 0, PAGE_SIZE,
- &mdev->device_len);
- if (!mdev->device)
- goto err_map_device;
- }
-
- return 0;
-
-err_map_device:
- if (mdev->notify_base)
- pci_iounmap(pci_dev, mdev->notify_base);
-err_map_notify:
- pci_iounmap(pci_dev, mdev->isr);
-err_map_isr:
- pci_iounmap(pci_dev, mdev->common);
-err_map_common:
- return err;
-}
-
/* the PCI probing function */
int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
{
@@ -1063,23 +463,6 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
return 0;
}

-/*
- * vp_modern_probe: remove and cleanup the modern virtio pci device
- * @mdev: the modern virtio-pci device
- */
-static void vp_modern_remove(struct virtio_pci_modern_device *mdev)
-{
- struct pci_dev *pci_dev = mdev->pci_dev;
-
- if (mdev->device)
- pci_iounmap(pci_dev, mdev->device);
- if (mdev->notify_base)
- pci_iounmap(pci_dev, mdev->notify_base);
- pci_iounmap(pci_dev, mdev->isr);
- pci_iounmap(pci_dev, mdev->common);
- pci_release_selected_regions(pci_dev, mdev->modern_bars);
-}
-
void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev)
{
struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
new file mode 100644
index 000000000000..cbd667496bb1
--- /dev/null
+++ b/drivers/virtio/virtio_pci_modern_dev.c
@@ -0,0 +1,599 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/virtio_pci_modern.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+/*
+ * vp_modern_map_capability - map a part of virtio pci capability
+ * @mdev: the modern virtio-pci device
+ * @off: offset of the capability
+ * @minlen: minimal length of the capability
+ * @align: align requirement
+ * @start: start from the capability
+ * @size: map size
+ * @len: the length that is actually mapped
+ *
+ * Returns the io address of for the part of the capability
+ */
+void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
+ size_t minlen,
+ u32 align,
+ u32 start, u32 size,
+ size_t *len)
+{
+ struct pci_dev *dev = mdev->pci_dev;
+ u8 bar;
+ u32 offset, length;
+ void __iomem *p;
+
+ pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
+ bar),
+ &bar);
+ pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
+ &offset);
+ pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
+ &length);
+
+ if (length <= start) {
+ dev_err(&dev->dev,
+ "virtio_pci: bad capability len %u (>%u expected)\n",
+ length, start);
+ return NULL;
+ }
+
+ if (length - start < minlen) {
+ dev_err(&dev->dev,
+ "virtio_pci: bad capability len %u (>=%zu expected)\n",
+ length, minlen);
+ return NULL;
+ }
+
+ length -= start;
+
+ if (start + offset < offset) {
+ dev_err(&dev->dev,
+ "virtio_pci: map wrap-around %u+%u\n",
+ start, offset);
+ return NULL;
+ }
+
+ offset += start;
+
+ if (offset & (align - 1)) {
+ dev_err(&dev->dev,
+ "virtio_pci: offset %u not aligned to %u\n",
+ offset, align);
+ return NULL;
+ }
+
+ if (length > size)
+ length = size;
+
+ if (len)
+ *len = length;
+
+ if (minlen + offset < minlen ||
+ minlen + offset > pci_resource_len(dev, bar)) {
+ dev_err(&dev->dev,
+ "virtio_pci: map virtio %zu@%u "
+ "out of range on bar %i length %lu\n",
+ minlen, offset,
+ bar, (unsigned long)pci_resource_len(dev, bar));
+ return NULL;
+ }
+
+ p = pci_iomap_range(dev, bar, offset, length);
+ if (!p)
+ dev_err(&dev->dev,
+ "virtio_pci: unable to map virtio %u@%u on bar %i\n",
+ length, offset, bar);
+ return p;
+}
+EXPORT_SYMBOL_GPL(vp_modern_map_capability);
+
+/**
+ * virtio_pci_find_capability - walk capabilities to find device info.
+ * @dev: the pci device
+ * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
+ * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
+ * @bars: the bitmask of BARs
+ *
+ * Returns offset of the capability, or 0.
+ */
+static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
+ u32 ioresource_types, int *bars)
+{
+ int pos;
+
+ for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
+ pos > 0;
+ pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
+ u8 type, bar;
+ pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
+ cfg_type),
+ &type);
+ pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
+ bar),
+ &bar);
+
+ /* Ignore structures with reserved BAR values */
+ if (bar > 0x5)
+ continue;
+
+ if (type == cfg_type) {
+ if (pci_resource_len(dev, bar) &&
+ pci_resource_flags(dev, bar) & ioresource_types) {
+ *bars |= (1 << bar);
+ return pos;
+ }
+ }
+ }
+ return 0;
+}
+
+/* This is part of the ABI. Don't screw with it. */
+static inline void check_offsets(void)
+{
+ /* Note: disk space was harmed in compilation of this function. */
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
+ offsetof(struct virtio_pci_cap, cap_vndr));
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
+ offsetof(struct virtio_pci_cap, cap_next));
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
+ offsetof(struct virtio_pci_cap, cap_len));
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
+ offsetof(struct virtio_pci_cap, cfg_type));
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
+ offsetof(struct virtio_pci_cap, bar));
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
+ offsetof(struct virtio_pci_cap, offset));
+ BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
+ offsetof(struct virtio_pci_cap, length));
+ BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
+ offsetof(struct virtio_pci_notify_cap,
+ notify_off_multiplier));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
+ offsetof(struct virtio_pci_common_cfg,
+ device_feature_select));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
+ offsetof(struct virtio_pci_common_cfg, device_feature));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
+ offsetof(struct virtio_pci_common_cfg,
+ guest_feature_select));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
+ offsetof(struct virtio_pci_common_cfg, guest_feature));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
+ offsetof(struct virtio_pci_common_cfg, msix_config));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
+ offsetof(struct virtio_pci_common_cfg, num_queues));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
+ offsetof(struct virtio_pci_common_cfg, device_status));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
+ offsetof(struct virtio_pci_common_cfg, config_generation));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
+ offsetof(struct virtio_pci_common_cfg, queue_select));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
+ offsetof(struct virtio_pci_common_cfg, queue_size));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
+ offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
+ offsetof(struct virtio_pci_common_cfg, queue_enable));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
+ offsetof(struct virtio_pci_common_cfg, queue_notify_off));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
+ offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
+ offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
+ offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
+ offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
+ offsetof(struct virtio_pci_common_cfg, queue_used_lo));
+ BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
+ offsetof(struct virtio_pci_common_cfg, queue_used_hi));
+}
+
+/*
+ * vp_modern_probe: probe the modern virtio pci device, note that the
+ * caller is required to enable PCI device before calling this function.
+ * @mdev: the modern virtio-pci device
+ *
+ * Return 0 on succeed otherwise fail
+ */
+int vp_modern_probe(struct virtio_pci_modern_device *mdev)
+{
+ struct pci_dev *pci_dev = mdev->pci_dev;
+ int err, common, isr, notify, device;
+ u32 notify_length;
+ u32 notify_offset;
+
+ check_offsets();
+
+ mdev->pci_dev = pci_dev;
+
+ /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
+ if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
+ return -ENODEV;
+
+ if (pci_dev->device < 0x1040) {
+ /* Transitional devices: use the PCI subsystem device id as
+ * virtio device id, same as legacy driver always did.
+ */
+ mdev->id.device = pci_dev->subsystem_device;
+ } else {
+ /* Modern devices: simply use PCI device id, but start from 0x1040. */
+ mdev->id.device = pci_dev->device - 0x1040;
+ }
+ mdev->id.vendor = pci_dev->subsystem_vendor;
+
+ /* check for a common config: if not, use legacy mode (bar 0). */
+ common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
+ IORESOURCE_IO | IORESOURCE_MEM,
+ &mdev->modern_bars);
+ if (!common) {
+ dev_info(&pci_dev->dev,
+ "virtio_pci: leaving for legacy driver\n");
+ return -ENODEV;
+ }
+
+ /* If common is there, these should be too... */
+ isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
+ IORESOURCE_IO | IORESOURCE_MEM,
+ &mdev->modern_bars);
+ notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
+ IORESOURCE_IO | IORESOURCE_MEM,
+ &mdev->modern_bars);
+ if (!isr || !notify) {
+ dev_err(&pci_dev->dev,
+ "virtio_pci: missing capabilities %i/%i/%i\n",
+ common, isr, notify);
+ return -EINVAL;
+ }
+
+ err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
+ if (err)
+ err = dma_set_mask_and_coherent(&pci_dev->dev,
+ DMA_BIT_MASK(32));
+ if (err)
+ dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
+
+ /* Device capability is only mandatory for devices that have
+ * device-specific configuration.
+ */
+ device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
+ IORESOURCE_IO | IORESOURCE_MEM,
+ &mdev->modern_bars);
+
+ err = pci_request_selected_regions(pci_dev, mdev->modern_bars,
+ "virtio-pci-modern");
+ if (err)
+ return err;
+
+ err = -EINVAL;
+ mdev->common = vp_modern_map_capability(mdev, common,
+ sizeof(struct virtio_pci_common_cfg), 4,
+ 0, sizeof(struct virtio_pci_common_cfg),
+ NULL);
+ if (!mdev->common)
+ goto err_map_common;
+ mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1,
+ 0, 1,
+ NULL);
+ if (!mdev->isr)
+ goto err_map_isr;
+
+ /* Read notify_off_multiplier from config space. */
+ pci_read_config_dword(pci_dev,
+ notify + offsetof(struct virtio_pci_notify_cap,
+ notify_off_multiplier),
+ &mdev->notify_offset_multiplier);
+ /* Read notify length and offset from config space. */
+ pci_read_config_dword(pci_dev,
+ notify + offsetof(struct virtio_pci_notify_cap,
+ cap.length),
+ &notify_length);
+
+ pci_read_config_dword(pci_dev,
+ notify + offsetof(struct virtio_pci_notify_cap,
+ cap.offset),
+ &notify_offset);
+
+ /* We don't know how many VQs we'll map, ahead of the time.
+ * If notify length is small, map it all now.
+ * Otherwise, map each VQ individually later.
+ */
+ if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
+ mdev->notify_base = vp_modern_map_capability(mdev, notify,
+ 2, 2,
+ 0, notify_length,
+ &mdev->notify_len);
+ if (!mdev->notify_base)
+ goto err_map_notify;
+ } else {
+ mdev->notify_map_cap = notify;
+ }
+
+ /* Again, we don't know how much we should map, but PAGE_SIZE
+ * is more than enough for all existing devices.
+ */
+ if (device) {
+ mdev->device = vp_modern_map_capability(mdev, device, 0, 4,
+ 0, PAGE_SIZE,
+ &mdev->device_len);
+ if (!mdev->device)
+ goto err_map_device;
+ }
+
+ return 0;
+
+err_map_device:
+ if (mdev->notify_base)
+ pci_iounmap(pci_dev, mdev->notify_base);
+err_map_notify:
+ pci_iounmap(pci_dev, mdev->isr);
+err_map_isr:
+ pci_iounmap(pci_dev, mdev->common);
+err_map_common:
+ return err;
+}
+EXPORT_SYMBOL_GPL(vp_modern_probe);
+
+/*
+ * vp_modern_probe: remove and cleanup the modern virtio pci device
+ * @mdev: the modern virtio-pci device
+ */
+void vp_modern_remove(struct virtio_pci_modern_device *mdev)
+{
+ struct pci_dev *pci_dev = mdev->pci_dev;
+
+ if (mdev->device)
+ pci_iounmap(pci_dev, mdev->device);
+ if (mdev->notify_base)
+ pci_iounmap(pci_dev, mdev->notify_base);
+ pci_iounmap(pci_dev, mdev->isr);
+ pci_iounmap(pci_dev, mdev->common);
+ pci_release_selected_regions(pci_dev, mdev->modern_bars);
+}
+EXPORT_SYMBOL_GPL(vp_modern_remove);
+
+/*
+ * vp_modern_get_features - get features from device
+ * @mdev: the modern virtio-pci device
+ *
+ * Returns the features read from the device
+ */
+u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ u64 features;
+
+ vp_iowrite32(0, &cfg->device_feature_select);
+ features = vp_ioread32(&cfg->device_feature);
+ vp_iowrite32(1, &cfg->device_feature_select);
+ features |= ((u64)vp_ioread32(&cfg->device_feature) << 32);
+
+ return features;
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_features);
+
+/*
+ * vp_modern_set_features - set features to device
+ * @mdev: the modern virtio-pci device
+ * @features: the features set to device
+ */
+void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
+ u64 features)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ vp_iowrite32(0, &cfg->guest_feature_select);
+ vp_iowrite32((u32)features, &cfg->guest_feature);
+ vp_iowrite32(1, &cfg->guest_feature_select);
+ vp_iowrite32(features >> 32, &cfg->guest_feature);
+}
+EXPORT_SYMBOL_GPL(vp_modern_set_features);
+
+/*
+ * vp_modern_generation - get the device genreation
+ * @mdev: the modern virtio-pci device
+ *
+ * Returns the genreation read from device
+ */
+u32 vp_modern_generation(struct virtio_pci_modern_device *mdev)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ return vp_ioread8(&cfg->config_generation);
+}
+EXPORT_SYMBOL_GPL(vp_modern_generation);
+
+/*
+ * vp_modern_get_status - get the device status
+ * @mdev: the modern virtio-pci device
+ *
+ * Returns the status read from device
+ */
+u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ return vp_ioread8(&cfg->device_status);
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_status);
+
+/*
+ * vp_modern_set_status - set status to device
+ * @mdev: the modern virtio-pci device
+ * @status: the status set to device
+ */
+void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
+ u8 status)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ vp_iowrite8(status, &cfg->device_status);
+}
+EXPORT_SYMBOL_GPL(vp_modern_set_status);
+
+/*
+ * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: queue index
+ * @vector: the config vector
+ *
+ * Returns the config vector read from the device
+ */
+u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
+ u16 index, u16 vector)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ vp_iowrite16(index, &cfg->queue_select);
+ vp_iowrite16(vector, &cfg->queue_msix_vector);
+ /* Flush the write out to device */
+ return vp_ioread16(&cfg->queue_msix_vector);
+}
+EXPORT_SYMBOL_GPL(vp_modern_queue_vector);
+
+/*
+ * vp_modern_config_vector - set the vector for config interrupt
+ * @mdev: the modern virtio-pci device
+ * @vector: the config vector
+ *
+ * Returns the config vector read from the device
+ */
+u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev,
+ u16 vector)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ /* Setup the vector used for configuration events */
+ vp_iowrite16(vector, &cfg->msix_config);
+ /* Verify we had enough resources to assign the vector */
+ /* Will also flush the write out to device */
+ return vp_ioread16(&cfg->msix_config);
+}
+EXPORT_SYMBOL_GPL(vp_modern_config_vector);
+
+/*
+ * vp_modern_queue_address - set the virtqueue address
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ * @desc_addr: address of the descriptor area
+ * @driver_addr: address of the driver area
+ * @device_addr: address of the device area
+ */
+void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
+ u16 index, u64 desc_addr, u64 driver_addr,
+ u64 device_addr)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ vp_iowrite16(index, &cfg->queue_select);
+
+ vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo,
+ &cfg->queue_desc_hi);
+ vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo,
+ &cfg->queue_avail_hi);
+ vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo,
+ &cfg->queue_used_hi);
+}
+EXPORT_SYMBOL_GPL(vp_modern_queue_address);
+
+/*
+ * vp_modern_set_queue_enable - enable a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ * @enable: whether the virtqueue is enable or not
+ */
+void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
+ u16 index, bool enable)
+{
+ vp_iowrite16(index, &mdev->common->queue_select);
+ vp_iowrite16(enable, &mdev->common->queue_enable);
+}
+EXPORT_SYMBOL_GPL(vp_modern_set_queue_enable);
+
+/*
+ * vp_modern_get_queue_enable - enable a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ *
+ * Returns whether a virtqueue is enabled or not
+ */
+bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
+ u16 index)
+{
+ vp_iowrite16(index, &mdev->common->queue_select);
+
+ return vp_ioread16(&mdev->common->queue_enable);
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_queue_enable);
+
+/*
+ * vp_modern_set_queue_size - set size for a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ * @size: the size of the virtqueue
+ */
+void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
+ u16 index, u16 size)
+{
+ vp_iowrite16(index, &mdev->common->queue_select);
+ vp_iowrite16(size, &mdev->common->queue_size);
+
+}
+EXPORT_SYMBOL_GPL(vp_modern_set_queue_size);
+
+/*
+ * vp_modern_get_queue_size - get size for a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ *
+ * Returns the size of the virtqueue
+ */
+u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
+ u16 index)
+{
+ vp_iowrite16(index, &mdev->common->queue_select);
+
+ return vp_ioread16(&mdev->common->queue_size);
+
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_queue_size);
+
+/*
+ * vp_modern_get_num_queues - get the number of virtqueues
+ * @mdev: the modern virtio-pci device
+ *
+ * Returns the number of virtqueues
+ */
+u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev)
+{
+ return vp_ioread16(&mdev->common->num_queues);
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_num_queues);
+
+/*
+ * vp_modern_get_queue_notify_off - get notification offset for a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ *
+ * Returns the notification offset for a virtqueue
+ */
+u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
+ u16 index)
+{
+ vp_iowrite16(index, &mdev->common->queue_select);
+
+ return vp_ioread16(&mdev->common->queue_notify_off);
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off);
+
+MODULE_VERSION("0.1");
+MODULE_DESCRIPTION("Modern Virtio PCI Device");
+MODULE_AUTHOR("Jason Wang <jasowang@xxxxxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
new file mode 100644
index 000000000000..f26acbeec965
--- /dev/null
+++ b/include/linux/virtio_pci_modern.h
@@ -0,0 +1,111 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_VIRTIO_PCI_MODERN_H
+#define _LINUX_VIRTIO_PCI_MODERN_H
+
+#include <linux/pci.h>
+#include <linux/virtio_pci.h>
+
+struct virtio_pci_modern_device {
+ struct pci_dev *pci_dev;
+
+ struct virtio_pci_common_cfg __iomem *common;
+ /* Device-specific data (non-legacy mode) */
+ void __iomem *device;
+ /* Base of vq notifications (non-legacy mode). */
+ void __iomem *notify_base;
+ /* Where to read and clear interrupt */
+ u8 __iomem *isr;
+
+ /* So we can sanity-check accesses. */
+ size_t notify_len;
+ size_t device_len;
+
+ /* Capability for when we need to map notifications per-vq. */
+ int notify_map_cap;
+
+ /* Multiply queue_notify_off by this value. (non-legacy mode). */
+ u32 notify_offset_multiplier;
+
+ int modern_bars;
+
+ struct virtio_device_id id;
+};
+
+/*
+ * Type-safe wrappers for io accesses.
+ * Use these to enforce at compile time the following spec requirement:
+ *
+ * The driver MUST access each field using the “natural” access
+ * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
+ * for 16-bit fields and 8-bit accesses for 8-bit fields.
+ */
+static inline u8 vp_ioread8(const u8 __iomem *addr)
+{
+ return ioread8(addr);
+}
+static inline u16 vp_ioread16 (const __le16 __iomem *addr)
+{
+ return ioread16(addr);
+}
+
+static inline u32 vp_ioread32(const __le32 __iomem *addr)
+{
+ return ioread32(addr);
+}
+
+static inline void vp_iowrite8(u8 value, u8 __iomem *addr)
+{
+ iowrite8(value, addr);
+}
+
+static inline void vp_iowrite16(u16 value, __le16 __iomem *addr)
+{
+ iowrite16(value, addr);
+}
+
+static inline void vp_iowrite32(u32 value, __le32 __iomem *addr)
+{
+ iowrite32(value, addr);
+}
+
+static inline void vp_iowrite64_twopart(u64 val,
+ __le32 __iomem *lo,
+ __le32 __iomem *hi)
+{
+ vp_iowrite32((u32)val, lo);
+ vp_iowrite32(val >> 32, hi);
+}
+
+u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev);
+void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
+ u64 features);
+u32 vp_modern_generation(struct virtio_pci_modern_device *mdev);
+u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev);
+void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
+ u8 status);
+u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
+ u16 idx, u16 vector);
+u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev,
+ u16 vector);
+void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
+ u16 index, u64 desc_addr, u64 driver_addr,
+ u64 device_addr);
+void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
+ u16 idx, bool enable);
+bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
+ u16 idx);
+void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
+ u16 idx, u16 size);
+u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
+ u16 idx);
+u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev);
+u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
+ u16 idx);
+void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
+ size_t minlen,
+ u32 align,
+ u32 start, u32 size,
+ size_t *len);
+int vp_modern_probe(struct virtio_pci_modern_device *mdev);
+void vp_modern_remove(struct virtio_pci_modern_device *mdev);
+#endif
--
2.25.1