Re: [PATCH 0/9] drm/tyr: add VM and BO ioctl support

[Deborah Brouwer <deborah.brouwer@collabora.com>]

On Wed, Sep 02, 2026 at 12:08:59AM +0800, Ke Sun wrote:
> Add the VM and BO ioctls to the Tyr driver, aligning its userspace
> interface with panthor. The series is based on Danilo's `drm-file`
> series on `drm-rust-next`, and uses the existing IdPool and xarray
> abstractions for per-file VM management.
> 
> The panthor IGT tests pass on an RK3588S device.

Hi Alvin,

Thanks for sending this series, I am still reviewing it but this is what I
noticed today:

1. Do we still need a separate pool module, since this is just for VmPool,
could we put it in vm.rs?

2. We might have a problem matching panthor’s 32 VMs per file, since the
minimum capacity of IdPool is MAX_INLINE_LEN. But maybe it will be ok to
extend this to 64 VMs per file. But then when we drop the vm pool we
better not rely on that PANTHOR_MAX_VMS_PER_FILE constant.

3. Also, I am not sure, but do we need to call vm.kill() when we drop the
vm_pool? Does it depend on the vms being activated? And if they have been
activated, should this go in Vm::drop() instead? 

4. Could you use dev_err! instead of pr_err! please, we tried to convert
over to that in the booting series.

5. We should be able to compile each patch in your series separately (to
help with future bisecting) so use the annotation #[expect(dead_code)] for
patches early in the series and then remove it in patches later in the
series when you actually use the code.

6. It would be nice if you could give a link to a repo where you have
applied all the prerequisite series and fixed conflicts. Could you still
update the branch from:
https://gitlab.freedesktop.org/panfrost/linux/-/merge_requests/64

Thanks,
Deborah

> 
> Signed-off-by: Ke Sun <sunke@kylinos.cn>
> ---
> Alvin Sun (9):
>       rust: sizes: add SZ_4G constant
>       rust: mm: add `task_size` helper
>       rust: sync: arc: relax `ForeignOwnable` for `Arc<T>`
>       drm/tyr: add per-file VM pool
>       drm/tyr: add user and MCU VM specifications
>       drm/tyr: add BO creation and lookup helpers
>       drm/tyr: refactor new_dummy_object to use new_object
>       drm/tyr: add VM-related ioctls
>       drm/tyr: add BO-related ioctls
> 
>  drivers/gpu/drm/tyr/driver.rs   |  14 +-
>  drivers/gpu/drm/tyr/file.rs     | 394 ++++++++++++++++++++++++++++++++++++++--
>  drivers/gpu/drm/tyr/fw.rs       |   8 +-
>  drivers/gpu/drm/tyr/gem.rs      |  41 ++++-
>  drivers/gpu/drm/tyr/pool.rs     | 102 +++++++++++
>  drivers/gpu/drm/tyr/tyr.rs      |   1 +
>  drivers/gpu/drm/tyr/vm.rs       | 158 +++++++++++++++-
>  rust/bindings/bindings_helper.h |   1 +
>  rust/kernel/mm.rs               |   7 +
>  rust/kernel/sizes.rs            |  12 ++
>  rust/kernel/sync/arc.rs         |  12 +-
>  11 files changed, 714 insertions(+), 36 deletions(-)
> ---
> base-commit: 0b0aa9dcf17b6cffa9e325ff641e843b20d40c31
> change-id: 20260901-tyr-ioctls-f10ef0dcbfa6
> 
> Best regards,
> -- 
> Ke Sun <sunke@kylinos.cn>
>