linux-toradex.git/include/linux/virtio.h, branch v6.12-rc4

virtio: allow driver to disable the configure change notification

2024-08-16T02:14:19+00:00

Sometime, it would be useful to disable the configure change
notification from the driver. So this patch allows this by introducing
a variable config_change_driver_disabled and only allow the configure
change notification callback to be triggered when it is allowed by
both the virtio core and the driver. It is set to false by default to
hold the current semantic so we don't need to change any drivers.

The first user for this would be virtio-net.

Cc: Venkat Venkatsubra 
Cc: Gia-Khanh Nguyen 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Jason Wang 
Link: https://patch.msgid.link/20240814052228.4654-3-jasowang@redhat.com
Signed-off-by: Jakub Kicinski

virtio: rename virtio_config_enabled to virtio_config_core_enabled

2024-08-16T02:14:19+00:00

Following patch will allow the config interrupt to be disabled by a
specific driver via another boolean. So this patch renames
virtio_config_enabled and relevant helpers to
virtio_config_core_enabled.

Cc: Venkat Venkatsubra 
Cc: Gia-Khanh Nguyen 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Jason Wang 
Link: https://patch.msgid.link/20240814052228.4654-2-jasowang@redhat.com
Signed-off-by: Jakub Kicinski

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

2024-07-29T19:53:37+00:00

Pull virtio fixes from Michael Tsirkin:
 "The biggest thing here is the adminq change - but it looks like the
  only way to avoid headq blocking causing indefinite stalls.

  This fixes three issues:

   - Prevent admin commands on one VF blocking another.

     This prevents a bad VF from blocking a good one, as well as fixing
     a scalability issue with large # of VFs

   - Correctly return error on command failure on octeon. We used to
     treat failed commands as a success.

   - Fix modpost warning when building virtio_dma_buf. Harmless, but the
     fix is trivial"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_pci_modern: remove admin queue serialization lock
  virtio_pci_modern: use completion instead of busy loop to wait on admin cmd result
  virtio_pci_modern: pass cmd as an identification token
  virtio_pci_modern: create admin queue of queried size
  virtio: create admin queues alongside other virtqueues
  virtio_pci: pass vq info as an argument to vp_setup_vq()
  virtio: push out code to vp_avq_index()
  virtio_pci_modern: treat vp_dev->admin_vq.info.vq pointer as static
  virtio_pci: introduce vector allocation fallback for slow path virtqueues
  virtio_pci: pass vector policy enum to vp_find_one_vq_msix()
  virtio_pci: pass vector policy enum to vp_find_vqs_msix()
  virtio_pci: simplify vp_request_msix_vectors() call a bit
  virtio_pci: push out single vq find code to vp_find_one_vq_msix()
  vdpa/octeon_ep: Fix error code in octep_process_mbox()
  virtio: add missing MODULE_DESCRIPTION() macro

virtio_pci_modern: use completion instead of busy loop to wait on admin cmd result

2024-07-17T09:43:21+00:00

Currently, the code waits in a busy loop on every admin virtqueue issued
command to get a reply. That prevents callers from issuing multiple
commands in parallel.

To overcome this limitation, introduce a virtqueue event callback for
admin virtqueue. For every issued command, use completion mechanism
to wait on a reply. In the event callback, trigger the completion
is done for every incoming reply.

Alongside with that, introduce a spin lock to protect the admin
virtqueue operations.

Signed-off-by: Jiri Pirko 
Message-Id: <20240716113552.80599-13-jiri@resnulli.us>
Signed-off-by: Michael S. Tsirkin

driver core: have match() callback in struct bus_type take a const *

2024-07-03T13:16:54+00:00

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *.  This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly.  This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki 
Reviewed-by: Alex Elder 
Acked-by: Sumit Garg 
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman

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: store owner from modules with register_virtio_driver()

2024-04-08T08:11:04+00:00

Modules registering driver with register_virtio_driver() might forget to
set .owner field.  i2c-virtio.c for example has it missing.  The field
is used by some other kernel parts for reference counting
(try_module_get()), so it is expected that drivers will set it.

Solve the problem by moving this task away from the drivers to the core
virtio code, just like we did for platform_driver in
commit 9447057eaff8 ("platform_device: use a macro instead of
platform_driver_register").

Fixes: 3cfc88380413 ("i2c: virtio: add a virtio i2c frontend driver")
Cc: "Jie Deng" 
Signed-off-by: Krzysztof Kozlowski 
Message-Id: <20240331-module-owner-virtio-v2-1-98f04bfaf46a@linaro.org>
Signed-off-by: Michael S. Tsirkin

virtio-pci: Introduce admin command sending function

2023-12-19T18:51:31+00:00

Add support for sending admin command through admin virtqueue interface.
Abort any inflight admin commands once device reset completes. Activate
admin queue when device becomes ready; deactivate on device reset.

To comply to the below specification statement [1], the admin virtqueue
is activated for upper layer users only after setting DRIVER_OK status.

[1] The driver MUST NOT send any buffer available notifications to the
device before setting DRIVER_OK.

Signed-off-by: Feng Liu 
Reviewed-by: Parav Pandit 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Yishai Hadas 
Link: https://lore.kernel.org/r/20231219093247.170936-4-yishaih@nvidia.com
Signed-off-by: Alex Williamson

Merge tag 'i2c-for-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

2023-09-04T20:44:11+00:00

Pull i2c updates from Wolfram Sang:
 "I2C has mainly cleanups this time and a few driver improvements.

  Because a lot of developers were on holidays (including myself) it was
  a good timing to apply lots of cleanups which would normally cause
  merge conflicts with other floating patches. Extra thanks go to Andi
  Shyti who backed me up when I was on a four week hiatus. This is also
  the reason that some patches were commited later than ideal"

* tag 'i2c-for-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (67 commits)
  i2c: at91: Use dev_err_probe() instead of dev_err()
  I2C: ali15x3: Do PCI error checks on own line
  i2c: Make return value check more accurate and explicit for devm_pinctrl_get()
  i2c: designware: Add support for recovery when GPIO need pinctrl
  i2c: mlxcpld: Add support for extended transaction length
  i2c: mlxcpld: Allow driver to run on ARM64 architecture
  i2c: nforce2: Do PCI error check on own line
  i2c: sis5595: Do PCI error checks on own line
  i2c: qcom-cci: Fix error checking in cci_probe()
  i2c: muxes: pca954x: Add regulator support
  i2c: muxes: pca954x: Add MAX735x/MAX736x support
  dt-bindings: i2c: Add Maxim MAX735x/MAX736x variants
  dt-bindings: i2c: pca954x: Correct interrupt support
  i2c: pnx: Use devm_platform_get_and_ioremap_resource()
  i2c: pxa: Use devm_platform_get_and_ioremap_resource()
  i2c: s3c2410: Use devm_platform_get_and_ioremap_resource()
  i2c: sh_mobile: Use devm_platform_get_and_ioremap_resource()
  i2c: st: Use devm_platform_get_and_ioremap_resource()
  i2c: qcom-geni: Convert to devm_platform_ioremap_resource()
  i2c: stm32f4: Use devm_platform_get_and_ioremap_resource()
  ...

virtio_ring: introduce dma sync api for virtqueue

2023-09-03T22:10:23+00:00

These API has been introduced:

* virtqueue_dma_need_sync
* virtqueue_dma_sync_single_range_for_cpu
* virtqueue_dma_sync_single_range_for_device

These APIs can be used together with the premapped mechanism to sync the
DMA address.

Signed-off-by: Xuan Zhuo 
Message-Id: <20230810123057.43407-12-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin