Re: [PATCH v3 10/13] PCI/TSM: Report active IDE streams

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Thu, 15 May 2025 22:47:29 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> Given that the platform TSM owns IDE Stream ID allocation, report the
> active streams via the TSM class device. Establish a symlink from the
> class device to the PCI endpoint device consuming the stream, named by
> the Stream ID.
> 
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  Documentation/ABI/testing/sysfs-class-tsm | 10 ++++++++++
>  drivers/virt/coco/host/tsm-core.c         | 17 +++++++++++++++++
>  include/linux/tsm.h                       |  4 ++++
>  3 files changed, 31 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-class-tsm b/Documentation/ABI/testing/sysfs-class-tsm
> index 7503f04a9eb9..75ee2b9bc555 100644
> --- a/Documentation/ABI/testing/sysfs-class-tsm
> +++ b/Documentation/ABI/testing/sysfs-class-tsm
> @@ -8,3 +8,13 @@ Description:
>  		signals when the PCI layer is able to support establishment of
>  		link encryption and other device-security features coordinated
>  		through the platform tsm.
> +
> +What:		/sys/class/tsm/tsm0/streamN:DDDD:BB:DD:F
> +Date:		December, 2024
> +Contact:	linux-pci@vger.kernel.org
> +Description:
> +		(RO) When a host bridge has established a secure connection via
> +		the platform TSM, symlink appears. The primary function of this
> +		is have a system global review of TSM resource consumption
> +		across host bridges. The link points to the endpoint PCI device
> +		at domain:DDDD bus:BB device:DD function:F.

Do we need the name to link to include the sbdf?  Maybe just streamN
is enough. It's a little fiddly to get the spdf from where that goes, but not
that challenging.

For user ls -lf /sys/class/tsm/tsm0/* should work for instance.

I don't care strongly about this. Maybe one for Bjorn.