[PATCH 9/9] drm/tyr: add BO-related ioctls

[Ke Sun via B4 Relay <devnull+sunke.kylinos.cn@kernel.org>]

From: Alvin Sun <alvin.sun@linux.dev>

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 <alvin.sun@linux.dev>
---
 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 {
+        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