virtio-pci: Introduce admin virtqueue

Introduce support for the admin virtqueue. By negotiating
VIRTIO_F_ADMIN_VQ feature, driver detects capability and creates one
administration virtqueue. Administration virtqueue implementation in
virtio pci generic layer, enables multiple types of upper layer
drivers such as vfio, net, blk to utilize it.

Signed-off-by: Feng Liu <feliu@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20231219093247.170936-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

virtio_pci: move structure to a header

These are guest/host interfaces, so they belong in the header where e.g.
qemu will know to find them.

Note: we added a new structure as opposed to extending existing one
because someone might be relying on the size of the existing structure
staying unchanged. Add a warning to avoid using sizeof.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>

virtio_pci: add check for common cfg size

Some buggy devices, the common cfg size may not match the features.

This patch checks the common cfg size for the
features(VIRTIO_F_NOTIF_CONFIG_DATA, VIRTIO_F_RING_RESET). When the
common cfg size does not match the corresponding feature, we fail the
probe and print error message.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231019034902.7346-1-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio: kdoc for struct virtio_pci_modern_device

Finally following up to Simon's suggestion for some kdoc attention
on struct virtio_pci_modern_device.

Link: https://lore.kernel.org/netdev/ZE%2FQS0lnUvxFacjf@corigine.com/
Cc: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20230911213104.14391-1-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

virtio: allow caller to override device DMA mask in vp_modern

To add a bit of vendor flexibility with various virtio based devices,
allow the caller to specify a different DMA mask. This adds a dma_mask
field to struct virtio_pci_modern_device. If defined by the driver,
this mask will be used in a call to dma_set_mask_and_coherent() instead
of the traditional DMA_BIT_MASK(64). This allows limiting the DMA space
on vendor devices with address limitations.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230519215632.12343-3-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio: allow caller to override device id in vp_modern

To add a bit of vendor flexibility with various virtio based devices,
allow the caller to check for a different device id. This adds a function
pointer field to struct virtio_pci_modern_device to specify an override
device id check. If defined by the driver, this function will be called
to check that the PCI device is the vendor's expected device, and will
return the found device id to be stored in mdev->id.device. This allows
vendors with alternative vendor device ids to use this library on their
own device BAR.

Note: A lot of the diff in this is simply indenting the existing code
into an else block.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230519215632.12343-2-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: introduce helper to get/set queue reset

Introduce new helpers to implement queue reset and get queue reset
status.

https://github.com/oasis-tcs/virtio-spec/issues/124
https://github.com/oasis-tcs/virtio-spec/issues/139

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-31-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: struct virtio_pci_common_cfg add queue_reset

Add queue_reset in virtio_pci_modern_common_cfg.

https://github.com/oasis-tcs/virtio-spec/issues/124
https://github.com/oasis-tcs/virtio-spec/issues/139

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-30-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio_pci: struct virtio_pci_common_cfg add queue_notify_data

Add queue_notify_data in struct virtio_pci_common_cfg, which comes from
here https://github.com/oasis-tcs/virtio-spec/issues/89

In order not to affect the API, add a dedicated structure struct
virtio_pci_modern_common_cfg to virtio_pci_modern.h.

Since I want to add queue_reset after queue_notify_data, I submitted
this patch first.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-26-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio-pci library: introduce vp_modern_get_driver_features()

This patch introduce a helper to get driver/guest features from the
device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210602021536.39525-3-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>

virtio_pci_modern: correct sparse tags for notify

When switching virtio_pci_modern to use a helper for mappings we lost an
__iomem tag. Restore it.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 9e3bb9b79a71 ("virtio_pci_modern: introduce helper to map vq notify area")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virtio-pci library: report resource address

Sometimes it might be useful to report the capability physical
address. One example is to report the physical address of the doorbell
in order to be mapped by userspace.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-7-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

virito_pci libray: hide vp_modern_map_capability()

No user now and the capability should not be setup
externally. Instead, every access to the capability should be done via
virtio_pci_modern_device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-6-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>

virtio_pci_modern: hide vp_modern_get_queue_notify_off()

All users (both virtio-pci library and vp_vdpa driver) has been
switched to use vp_modern_map_vq_notify(). So there's no need to
export the low level helper of vp_modern_get_queue_notify_off().

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-5-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>

virtio_pci_modern: introduce helper to map vq notify area

This patch factors out the logic of vq notify area mapping. Following
patches will switch to use this common helpers for both virtio_pci
library and virtio-pci vDPA driver.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>

virtio-pci: introduce modern device module

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210104065503.199631-17-jasowang@redhat.com

Including a bugfix:

virtio: don't prompt CONFIG_VIRTIO_PCI_MODERN

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 86b87c9d858b6 ("virtio-pci: introduce modern device module")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210223061905.422659-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>