kernel/linux.git/include/linux/virtio.h, branch v6.19.11

virtio: make it self-contained

2025-12-24T13:02:55+00:00

virtio.h uses struct module, add a forward declaration to make the header self-contained. Message-ID: <9171b5cac60793eb59ab044c96ee038bf1363bee.1764873799.git.mst@redhat.com> Acked-by: Jason Wang Signed-off-by: Michael S. Tsirkin

virtio: clean up features qword/dword terms

2025-11-27T07:03:07+00:00

virtio pci uses word to mean "16 bits". mmio uses it to mean "32 bits". To avoid confusion, let's avoid the term in core virtio altogether. Just say U64 to mean "64 bit". Fixes: e7d4c1c5a546 ("virtio: introduce extended features") Cc: Paolo Abeni Acked-by: Jason Wang Message-ID: Signed-off-by: Michael S. Tsirkin

vduse: switch to use virtio map API instead of DMA API

2025-10-01T11:24:55+00:00

Lacking the support of device specific mapping supported in virtio, VDUSE must trick the DMA API in order to make virtio-vdpa transport work. This is done by advertising vDPA device as dma device with a VDUSE specific dma_ops even if it doesn't do DMA at all. This will be fixed by this patch. Thanks to the new mapping operations support by virtio and vDPA. VDUSE can simply switch to advertise its specific mappings operations to virtio via virtio-vdpa then DMA API is not needed for VDUSE any more and iova domain could be used as the mapping token instead. Signed-off-by: Jason Wang Message-Id: <20250924070045.10361-3-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Eugenio Pérez

virtio: introduce map ops in virtio core

2025-10-01T11:24:43+00:00

This patch introduces map operations for virtio device. Virtio used to use DMA API which is not necessarily the case since some devices doesn't do DMA. Instead of using tricks and abusing DMA API, let's simply abstract the current mapping logic into a virtio specific mapping operations. For the device or transport that doesn't do DMA, they can implement their own mapping logic without the need to trick DMA core. In this case the mapping metadata is opaque to the virtio core that will be passed back to the transport or device specific map operations. For other devices, DMA API will still be used, so map token will still be the dma device to minimize the changeset and performance impact. The mapping operations are abstracted as a independent structure instead of reusing virtio_config_ops. This allows the transport can simply reuse the structure for lower layers like vDPA. A set of new mapping helpers were introduced for the device that want to do mapping by themselves. Signed-off-by: Jason Wang Message-Id: <20250821064641.5025-7-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Tested-by: Lei Yang Reviewed-by: Eugenio Pérez

virtio: introduce virtio_map container union

2025-10-01T11:24:43+00:00

Following patch will introduce the mapping operations for virtio device. In order to achieve this, besides the dma device, virtio core needs to support a transport or device specific mapping metadata as well. So this patch introduces a union container of a dma device. The idea is the allow the transport layer to pass device specific mapping metadata which will be used as a parameter for the virtio mapping operations. For the transport or device that is using DMA, dma device is still being used. Signed-off-by: Jason Wang Message-Id: <20250821064641.5025-5-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Tested-by: Lei Yang Reviewed-by: Eugenio Pérez

virtio: rename dma helpers

2025-10-01T11:24:43+00:00

Following patch will introduce virtio mapping function to avoid abusing DMA API for device that doesn't do DMA. To ease the introduction, this patch rename "dma" to "map" for the current dma mapping helpers. Reviewed-by: Christoph Hellwig Reviewed-by: Xuan Zhuo Signed-off-by: Jason Wang Message-Id: <20250821064641.5025-4-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Tested-by: Lei Yang Reviewed-by: Eugenio Pérez

virtio_ring: constify virtqueue pointer for DMA helpers

2025-10-01T11:24:43+00:00

This patch constifies the virtqueue pointer for DMA helpers. Reviewed-by: Christoph Hellwig Reviewed-by: Xuan Zhuo Reviewed-by: Eugenio Pérez Signed-off-by: Jason Wang Message-Id: <20250821064641.5025-2-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Tested-by: Lei Yang Reviewed-by: Eugenio Pérez

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2025-08-01T21:17:48+00:00

Pull virtio updates from Michael Tsirkin: - vhost can now support legacy threading if enabled in Kconfig - vsock memory allocation strategies for large buffers have been improved, reducing pressure on kmalloc - vhost now supports the in-order feature. guest bits missed the merge window. - fixes, cleanups all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (30 commits) vsock/virtio: Allocate nonlinear SKBs for handling large transmit buffers vsock/virtio: Rename virtio_vsock_skb_rx_put() vhost/vsock: Allocate nonlinear SKBs for handling large receive buffers vsock/virtio: Move SKB allocation lower-bound check to callers vsock/virtio: Rename virtio_vsock_alloc_skb() vsock/virtio: Resize receive buffers so that each SKB fits in a 4K page vsock/virtio: Move length check to callers of virtio_vsock_skb_rx_put() vsock/virtio: Validate length in packet header before skb_put() vhost/vsock: Avoid allocating arbitrarily-sized SKBs vhost_net: basic in_order support vhost: basic in order support vhost: fail early when __vhost_add_used() fails vhost: Reintroduce kthread API and add mode selection vdpa: Fix IDR memory leak in VDUSE module exit vdpa/mlx5: Fix release of uninitialized resources on error path vhost-scsi: Fix check for inline_sg_cnt exceeding preallocated limit virtio: virtio_dma_buf: fix missing parameter documentation vhost: Fix typos vhost: vringh: Remove unused functions vhost: vringh: Remove unused iotlb functions ...

virtio-mmio: Remove virtqueue list from mmio device

2025-08-01T13:11:07+00:00

The MMIO transport implementation creates a list of virtqueues for a virtio device, while the same is already available in the struct virtio_device. Don't create a duplicate list, and use the other one instead. While at it, fix the virtio_device_for_each_vq() macro to accept an argument like "&vm_dev->vdev" (which currently fails to build). Signed-off-by: Viresh Kumar Message-Id: <3e56c6f74002987e22f364d883cbad177cd9ad9c.1747827066.git.viresh.kumar@linaro.org> Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang

virtio: introduce extended features

2025-07-08T16:04:58+00:00

The virtio specifications allows for up to 128 bits for the device features. Soon we are going to use some of the 'extended' bits features (above 64) for the virtio_net driver. Introduce extended features as a fixed size array of u64. To minimize the diffstat allows legacy driver to access the low 64 bits via a transparent union. Introduce an extended get_extended_features configuration callback that devices supporting the extended features range must implement in place of the traditional one. Note that legacy and transport features don't need any change, as they are always in the low 64 bit range. Acked-by: Jason Wang Signed-off-by: Paolo Abeni