by Jason Wang

[permalink] [raw]

Subject: Re: [PATCH V3 16/19] virtio-pci: introduce modern device module

On 2021/2/10 下午8:35, Michael S. Tsirkin wrote:
> On Wed, Feb 10, 2021 at 12:44:03PM +0800, Jason Wang wrote:
>> On 2021/2/9 下午10:20, Michael S. Tsirkin wrote:
>>> On Mon, Jan 04, 2021 at 02:55:00PM +0800, Jason Wang wrote:
>>>> Signed-off-by: Jason Wang <[email protected]>
>>>> ---
>>>> 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..6b9b81f4b8c2 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 implements the
>>>> + basic probe and control for devices which are 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
>>> Looks like VIRTIO_PCI_MODERN is actually just a library that
>>> virtio pci uses. Is that right?
>>
>> Right.
>>
>>
>>> In that case just select it
>>> automatically, let's not make users enable it manually.
>>
>> I've considered to do this but the problem is that the module depends on PCI
>> so it can't be selected I think.
> Drop the dependency, document that whoever selects it must depend on PCI.

Fine with me. Will post a patch.

Thanks

>
>> Thanks
>>
>>

2021-02-19 08:35:27

by Jason Wang

[permalink] [raw]

Subject: Re: [PATCH V3 16/19] virtio-pci: introduce modern device module

On 2021/2/13 4:14 上午, Guenter Roeck wrote:
> On Mon, Jan 04, 2021 at 02:55:00PM +0800, Jason Wang wrote:
>> Signed-off-by: Jason Wang <[email protected]>
>> Reported-by: Naresh Kamboju <[email protected]>
> I don't really see the point of having to enable VIRTIO_PCI_MODERN
> because otherwise VIRTIO_PCI no longer works. If VIRTIO_PCI now
> requires VIRTIO_PCI_MODERN, maybe it should select it instead of
> depending on it ?

Right.

I will post a patch soon to select that.

Thanks

> Alternatively, you could just drop the new
> configuration flag entirely and build virtio_pci_modern_dev.o with
> VIRTIO_PCI. One doesn't work without the other anyway, after all.
>
> Guenter
>
>> ---
>> 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..6b9b81f4b8c2 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 implements the
>> + basic probe and control for devices which are 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 <[email protected]>");
>> +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