kernel/linux.git/drivers/virtio/Makefile, branch v6.12.80

virtio: add debugfs infrastructure to allow to debug virtio features

2024-04-26T11:26:53+00:00

Currently there is no way for user to set what features the driver should obey or not, it is hard wired in the code. In order to be able to debug the device behavior in case some feature is disabled, introduce a debugfs infrastructure with couple of files allowing user to see what features the device advertises and to set filter for features used by driver. Example: $cat /sys/bus/virtio/devices/virtio0/features 1110010111111111111101010000110010000000100000000000000000000000 $ echo "5" >/sys/kernel/debug/virtio/virtio0/filter_feature_add $ cat /sys/kernel/debug/virtio/virtio0/filter_features 5 $ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/unbind $ echo "virtio0" > /sys/bus/virtio/drivers/virtio_net/bind $ cat /sys/bus/virtio/devices/virtio0/features 1110000111111111111101010000110010000000100000000000000000000000 Note that sysfs "features" now already exists, this patch does not touch it. Signed-off-by: Jiri Pirko Acked-by: Michael S. Tsirkin Signed-off-by: Paolo Abeni

virtio-pci: Introduce APIs to execute legacy IO admin commands

2023-12-19T18:51:33+00:00

Introduce APIs to execute legacy IO admin commands. It includes: io_legacy_read/write for both common and the device configuration, io_legacy_notify_info. In addition, exposing an API to check whether the legacy IO commands are supported. (i.e. virtio_pci_admin_has_legacy_io()). Those APIs will be used by the next patches from this series. Note: Unlike modern drivers which support hardware virtio devices, legacy drivers assume software-based devices: e.g. they don't use proper memory barriers on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more or less by chance. For now, only support legacy IO on X86. Acked-by: Michael S. Tsirkin Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20231219093247.170936-7-yishaih@nvidia.com Signed-off-by: Alex Williamson

virtio: replace restricted mem access flag with callback

2022-08-01T05:42:49+00:00

Instead of having a global flag to require restricted memory access for all virtio devices, introduce a callback which can select that requirement on a per-device basis. For convenience add a common function returning always true, which can be used for use cases like SEV. Per default use a callback always returning false. As the callback needs to be set in early init code already, add a virtio anchor which is builtin in case virtio is enabled. Signed-off-by: Juergen Gross Tested-by: Oleksandr Tyshchenko # Arm64 guest using Xen Reviewed-by: Stefano Stabellini Link: https://lore.kernel.org/r/20220622063838.8854-2-jgross@suse.com Signed-off-by: Juergen Gross

virtio-pci: introduce legacy device module

2021-11-01T08:30:34+00:00

Split common codes from virtio-pci-legacy so vDPA driver can reuse it later. Signed-off-by: Wu Zongyong Acked-by: Jason Wang Link: https://lore.kernel.org/r/71605acde5e97fcb2760a6973e406279fb1bbd33.1635493219.git.wuzongyong@linux.alibaba.com Signed-off-by: Michael S. Tsirkin

virtio-pci: introduce modern device module

2021-02-23T12:52:58+00:00

Signed-off-by: Jason Wang 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 Cc: Anders Roxell Cc: Guenter Roeck Reported-by: Naresh Kamboju Fixes: 86b87c9d858b6 ("virtio-pci: introduce modern device module") Signed-off-by: Jason Wang Acked-by: Arnd Bergmann Link: https://lore.kernel.org/r/20210223061905.422659-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin

virtio: fix build for configs without dma-bufs

2020-08-19T04:43:28+00:00

Reported-by: kernel test robot Signed-off-by: David Stevens Link: http://patchwork.freedesktop.org/patch/msgid/20200819031011.310180-1-stevensd@chromium.org Signed-off-by: Gerd Hoffmann

virtio: add dma-buf support for exported objects

2020-08-18T08:01:44+00:00

This change adds a new flavor of dma-bufs that can be used by virtio drivers to share exported objects. A virtio dma-buf can be queried by virtio drivers to obtain the UUID which identifies the underlying exported object. Signed-off-by: David Stevens Acked-by: Michael S. Tsirkin Link: http://patchwork.freedesktop.org/patch/msgid/20200818071343.3461203-2-stevensd@chromium.org Signed-off-by: Gerd Hoffmann

virtio-mem: Paravirtualized memory hotplug

2020-06-04T19:36:52+00:00

Each virtio-mem device owns exactly one memory region. It is responsible for adding/removing memory from that memory region on request. When the device driver starts up, the requested amount of memory is queried and then plugged to Linux. On request, further memory can be plugged or unplugged. This patch only implements the plugging part. On x86-64, memory can currently be plugged in 4MB ("subblock") granularity. When required, a new memory block will be added (e.g., usually 128MB on x86-64) in order to plug more subblocks. Only x86-64 was tested for now. The online_page callback is used to keep unplugged subblocks offline when onlining memory - similar to the Hyper-V balloon driver. Unplugged pages are marked PG_offline, to tell dump tools (e.g., makedumpfile) to skip them. User space is usually responsible for onlining the added memory. The memory hotplug notifier is used to synchronize virtio-mem activity against memory onlining/offlining. Each virtio-mem device can belong to a NUMA node, which allows us to easily add/remove small chunks of memory to/from a specific NUMA node by using multiple virtio-mem devices. Something that works even when the guest has no idea about the NUMA topology. One way to view virtio-mem is as a "resizable DIMM" or a DIMM with many "sub-DIMMS". This patch directly introduces the basic infrastructure to implement memory unplug. Especially the memory block states and subblock bitmaps will be heavily used there. Notes: - In case memory is to be onlined by user space, we limit the amount of offline memory blocks, to not run out of memory. This is esp. an issue if memory is added faster than it is getting onlined. - Suspend/Hibernate is not supported due to the way virtio-mem devices behave. Limited support might be possible in the future. - Reloading the device driver is not supported. Reviewed-by: Pankaj Gupta Tested-by: Pankaj Gupta Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: Oscar Salvador Cc: Michal Hocko Cc: Igor Mammedov Cc: Dave Young Cc: Andrew Morton Cc: Dan Williams Cc: Pavel Tatashin Cc: Stefan Hajnoczi Cc: Vlastimil Babka Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: linux-acpi@vger.kernel.org Signed-off-by: David Hildenbrand Link: https://lore.kernel.org/r/20200507140139.17083-2-david@redhat.com Signed-off-by: Michael S. Tsirkin

vdpa: move to drivers/vdpa

2020-04-02T14:41:40+00:00

We have both vhost and virtio drivers that depend on vdpa. It's easier to locate it at a top level directory otherwise we run into issues e.g. if vhost is built-in but virtio is modular. Let's just move it up a level. Reported-by: Randy Dunlap Signed-off-by: Michael S. Tsirkin

virtio: introduce a vDPA based transport

2020-04-01T16:06:26+00:00

This patch introduces a vDPA transport for virtio. This is used to use kernel virtio driver to drive the vDPA device that is capable of populating virtqueue directly. A new virtio-vdpa driver will be registered to the vDPA bus, when a new virtio-vdpa device is probed, it will register the device with vdpa based config ops. This means it is a software transport between vDPA driver and vDPA device. The transport was implemented through bus_ops of vDPA parent. Signed-off-by: Jason Wang Link: https://lore.kernel.org/r/20200326140125.19794-7-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin