> On 1 Sep 2026, at 13:09, Ke Sun via B4 Relay
> <[email protected]> wrote:
>
> From: Alvin Sun <[email protected]>
>
> Expose buffer creation and BO mmap offset retrieval.
>
> - BO_CREATE page-aligns the size and returns a handle with
> write-combined mapping.
> - BO_MMAP_OFFSET provides the offset for the DRM generic mmap
> path, rejecting NO_MMAP objects and non-zero pad.
>
> Signed-off-by: Alvin Sun <[email protected]>
Same comment as the previous patches, please write a few
more things here about why the changes are needed.
With that addressed,
Reviewed-by: Daniel Almeida <[email protected]>
> ---
> drivers/gpu/drm/tyr/driver.rs | 2 ++
> drivers/gpu/drm/tyr/file.rs | 70 +++++++++++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/tyr/gem.rs | 7 +++++
> 3 files changed, 79 insertions(+)
>
> diff --git a/drivers/gpu/drm/tyr/driver.rs b/drivers/gpu/drm/tyr/driver.rs
> index b3145526ada06..fc8d11c9ba1ca 100644
> --- a/drivers/gpu/drm/tyr/driver.rs
> +++ b/drivers/gpu/drm/tyr/driver.rs
> @@ -224,6 +224,8 @@ impl drm::Driver for TyrDrmDriver {
> (PANTHOR_VM_DESTROY, drm_panthor_vm_destroy, ioctl::RENDER_ALLOW,
> TyrDrmFileData::vm_destroy),
> (PANTHOR_VM_BIND, drm_panthor_vm_bind, ioctl::RENDER_ALLOW,
> TyrDrmFileData::vm_bind),
> (PANTHOR_VM_GET_STATE, drm_panthor_vm_get_state, ioctl::RENDER_ALLOW,
> TyrDrmFileData::vm_get_state),
> + (PANTHOR_BO_CREATE, drm_panthor_bo_create, ioctl::RENDER_ALLOW,
> TyrDrmFileData::bo_create),
> + (PANTHOR_BO_MMAP_OFFSET, drm_panthor_bo_mmap_offset,
> ioctl::RENDER_ALLOW, TyrDrmFileData::bo_mmap_offset),
> }
> }
>
> diff --git a/drivers/gpu/drm/tyr/file.rs b/drivers/gpu/drm/tyr/file.rs
> index 157bc40e1cac4..16abf2968299c 100644
> --- a/drivers/gpu/drm/tyr/file.rs
> +++ b/drivers/gpu/drm/tyr/file.rs
> @@ -252,6 +252,76 @@ pub(crate) fn vm_get_state(
> Ok(0)
> })
> }
> +
> + pub(crate) fn bo_create(
> + ddev: &TyrDrmDevice<Registered>,
> + _reg_data: &TyrDrmRegistrationData<'_>,
> + bocreate: &mut uapi::drm_panthor_bo_create,
> + file: &TyrDrmFile,
> + ) -> Result<u32> {
> + if bocreate.size == 0
> + || bocreate.pad != 0
> + || bocreate.flags &
> !uapi::drm_panthor_bo_flags_DRM_PANTHOR_BO_NO_MMAP != 0
> + || bocreate.exclusive_vm_id != 0
> + {
> + dev_err!(
> + ddev.as_ref(),
> + "Invalid BO_CREATE params: size={}, pad={}, flags={:#x},
> exclusive_vm_id={}\n",
> + bocreate.size,
> + bocreate.pad,
> + bocreate.flags,
> + bocreate.exclusive_vm_id
> + );
> + return Err(EINVAL);
> + }
> +
> + let size = usize::try_from(bocreate.size).map_err(|_| {
> + dev_err!(
> + ddev.as_ref(),
> + "BO_CREATE size {:#x} too large\n",
> + bocreate.size
> + );
> + EINVAL
> + })?;
> + let bo = crate::gem::new_object(ddev, size, bocreate.flags)?;
> + bocreate.handle = bo.create_handle(file)?;
> + bocreate.size = bo.size() as u64;
> +
> + Ok(0)
> + }
> +
> + pub(crate) fn bo_mmap_offset(
> + ddev: &TyrDrmDevice<Registered>,
> + _reg_data: &TyrDrmRegistrationData<'_>,
> + bommap: &mut uapi::drm_panthor_bo_mmap_offset,
> + file: &TyrDrmFile,
> + ) -> Result<u32> {
> + if bommap.pad != 0 {
> + dev_err!(
> + ddev.as_ref(),
> + "BO mmap offset pad not zero: {}\n",
> + bommap.pad
> + );
> + return Err(EINVAL);
> + }
> +
> + let bo = crate::gem::lookup_handle(file,
> bommap.handle).inspect_err(|_| {
> + dev_err!(ddev.as_ref(), "Invalid BO mmap handle: {}\n",
> bommap.handle);
> + })?;
> + if bo.create_flags() &
> uapi::drm_panthor_bo_flags_DRM_PANTHOR_BO_NO_MMAP != 0 {
> + dev_err!(ddev.as_ref(), "BO mmap offset on NO_MMAP object\n");
> + return Err(EPERM);
> + }
> + bommap.offset = bo.create_mmap_offset().inspect_err(|_| {
> + dev_err!(
> + ddev.as_ref(),
> + "Failed to create mmap offset for handle {}\n",
> + bommap.handle
> + );
> + })?;
> +
> + Ok(0)
> + }
> }
>
> fn vm_bind_exec_op(vm: &Vm<'_>, file: &TyrDrmFile, op: &VmBindOp) -> Result {
> diff --git a/drivers/gpu/drm/tyr/gem.rs b/drivers/gpu/drm/tyr/gem.rs
> index d9ddcb287f52b..f404139f54f32 100644
> --- a/drivers/gpu/drm/tyr/gem.rs
> +++ b/drivers/gpu/drm/tyr/gem.rs
> @@ -38,6 +38,13 @@ pub(crate) struct BoData {
> flags: u32,
> }
>
> +impl BoData {
> + /// Returns the flags the BO was created with.
> + pub(crate) fn create_flags(&self) -> u32 {
I would prefer flags() instead of create_flags(), which reads a bit more like a
constructor.
> + self.flags
> + }
> +}
> +
> /// Provides a way to pass arguments when creating BoData
> /// as required by the gem::DriverObject trait.
> pub(crate) struct BoCreateArgs {
>
> --
> 2.43.0
>
>
>
