Add CHANGE_HANDLE ioctl for drm gem v2

Add CHANGE_HANDLE ioctl for drm gem v2

[David Francis]

This patch adds a new ioctl GEM_CHANGE_HANDLE which is needed by
amdgpu CRIU for dmabuf.

The ioctl allows a user to move a gem object to a new handle.

In this version, I have added kerneldoc comments for the new ioctl
in drm.h and have moved over the other drm_gem.c ioctl docs
to drm.h.

Accompanying changes:
kernel (for dmabuf CRIU support)
https://lore.kernel.org/dri-devel/20250617194536.538681-1-David.Francis@amd.com/
igt (for this ioctl)
https://gitlab.freedesktop.org/fdavid-amd/igt-gpu-tools
CRIU (for dmabuf CRIU support)
https://github.com/checkpoint-restore/criu/pull/2613

[PATCH 1/2] drm: Add DRM prime interface to reassign GEM handle

[David Francis]

CRIU restore of drm buffer objects requires the ability to create
or import a buffer object with a specific gem handle.

Add new drm ioctl DRM_IOCTL_GEM_CHANGE_HANDLE, which takes
the gem handle of an object and moves that object to a
specified new gem handle.

This ioctl needs to call drm_prime_remove_buf_handle,
but that function acquires the prime lock, which the ioctl
needs to hold for other purposes.

Make drm_prime_remove_buf_handle not acquire the prime lock,
and change its other caller to reflect this.

The rest of the kernel patches required to enable CRIU can be
found at
https://lore.kernel.org/dri-devel/20250617194536.538681-1-David.Francis@amd.com/

Signed-off-by: David Francis <David.Francis@amd.com>
---
 drivers/gpu/drm/drm_gem.c      | 54 ++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_internal.h |  4 +++
 drivers/gpu/drm/drm_ioctl.c    |  1 +
 drivers/gpu/drm/drm_prime.c    |  6 +---
 include/uapi/drm/drm.h         | 23 +++++++++++++++
 5 files changed, 83 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index c6240bab3fa5..3166230d0119 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -282,7 +282,12 @@ drm_gem_object_release_handle(int id, void *ptr, void *data)
 	if (obj->funcs->close)
 		obj->funcs->close(obj, file_priv);
 
+	mutex_lock(&file_priv->prime.lock);
+
 	drm_prime_remove_buf_handle(&file_priv->prime, id);
+
+	mutex_unlock(&file_priv->prime.lock);
+
 	drm_vma_node_revoke(&obj->vma_node, file_priv);
 
 	drm_gem_object_handle_put_unlocked(obj);
@@ -933,6 +938,55 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data,
 	return ret;
 }
 
+int drm_gem_change_handle_ioctl(struct drm_device *dev, void *data,
+				struct drm_file *file_priv)
+{
+	struct drm_gem_change_handle *args = data;
+	struct drm_gem_object *obj;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_GEM))
+		return -EOPNOTSUPP;
+
+	obj = drm_gem_object_lookup(file_priv, args->handle);
+	if (!obj)
+		return -ENOENT;
+
+	if (args->handle == args->new_handle)
+		return 0;
+
+	mutex_lock(&file_priv->prime.lock);
+
+	spin_lock(&file_priv->table_lock);
+	ret = idr_alloc(&file_priv->object_idr, obj,
+		args->new_handle, args->new_handle + 1, GFP_NOWAIT);
+	spin_unlock(&file_priv->table_lock);
+
+	if (ret < 0)
+		goto out_unlock;
+
+	if (obj->dma_buf) {
+		ret = drm_prime_add_buf_handle(&file_priv->prime, obj->dma_buf, args->new_handle);
+		if (ret < 0) {
+			spin_lock(&file_priv->table_lock);
+			idr_remove(&file_priv->object_idr, args->new_handle);
+			spin_unlock(&file_priv->table_lock);
+			goto out_unlock;
+		}
+
+		drm_prime_remove_buf_handle(&file_priv->prime, args->handle);
+	}
+
+	spin_lock(&file_priv->table_lock);
+	idr_remove(&file_priv->object_idr, args->handle);
+	spin_unlock(&file_priv->table_lock);
+
+out_unlock:
+	mutex_unlock(&file_priv->prime.lock);
+
+	return ret;
+}
+
 /**
  * drm_gem_open - initializes GEM file-private structures at devnode open time
  * @dev: drm_device which is being opened by userspace
diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h
index b2b6a8e49dda..e9d5cdf7e033 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -85,6 +85,8 @@ int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data,
 
 void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv);
 void drm_prime_destroy_file_private(struct drm_prime_file_private *prime_fpriv);
+int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
+			     struct dma_buf *dma_buf, uint32_t handle);
 void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
 				 uint32_t handle);
 
@@ -168,6 +170,8 @@ int drm_gem_close_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file_priv);
 int drm_gem_flink_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file_priv);
+int drm_gem_change_handle_ioctl(struct drm_device *dev, void *data,
+				struct drm_file *file_priv);
 int drm_gem_open_ioctl(struct drm_device *dev, void *data,
 		       struct drm_file *file_priv);
 void drm_gem_open(struct drm_device *dev, struct drm_file *file_private);
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index f593dc569d31..d8a24875a7ba 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -653,6 +653,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
 	DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
+	DRM_IOCTL_DEF(DRM_IOCTL_GEM_CHANGE_HANDLE, drm_gem_change_handle_ioctl, DRM_RENDER_ALLOW),
 
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
 
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index bdb51c8f262e..1f2e858e5000 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -93,7 +93,7 @@ struct drm_prime_member {
 	struct rb_node handle_rb;
 };
 
-static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
+int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
 				    struct dma_buf *dma_buf, uint32_t handle)
 {
 	struct drm_prime_member *member;
@@ -190,8 +190,6 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
 {
 	struct rb_node *rb;
 
-	mutex_lock(&prime_fpriv->lock);
-
 	rb = prime_fpriv->handles.rb_node;
 	while (rb) {
 		struct drm_prime_member *member;
@@ -210,8 +208,6 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
 			rb = rb->rb_left;
 		}
 	}
-
-	mutex_unlock(&prime_fpriv->lock);
 }
 
 void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv)
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 7fba37b94401..e3940b657e16 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -625,6 +625,21 @@ struct drm_gem_open {
 	__u64 size;
 };
 
+/**
+ * struct drm_gem_change_handle - Argument for &DRM_IOCTL_GEM_CHANGE_HANDLE ioctl.
+ * @handle: The handle of a gem object.
+ * @new_handle: An available gem handle.
+ *
+ * This ioctl changes the handle of a GEM object to the specified one.
+ * The new handle must be unused. On success the old handle is closed
+ * and all further IOCTL should refer to the new handle only.
+ * Calls to DRM_IOCTL_PRIME_FD_TO_HANDLE will return the new handle.
+ */
+struct drm_gem_change_handle {
+	__u32 handle;
+	__u32 new_handle;
+};
+
 /**
  * DRM_CAP_DUMB_BUFFER
  *
@@ -1305,6 +1320,14 @@ extern "C" {
  */
 #define DRM_IOCTL_SET_CLIENT_NAME	DRM_IOWR(0xD1, struct drm_set_client_name)
 
+/**
+ * DRM_IOCTL_GEM_CHANGE_HANDLE - Move an object to a different handle
+ *
+ * Some applications (notably CRIU) need objects to have specific gem handles.
+ * This ioctl changes the object at one gem handle to use a new gem handle.
+ */
+#define DRM_IOCTL_GEM_CHANGE_HANDLE    DRM_IOWR(0xD2, struct drm_gem_change_handle)
+
 /*
  * Device specific ioctls should only be in their respective headers
  * The device specific ioctl range is from 0x40 to 0x9f.
-- 
2.34.1

[PATCH 2/2] drm: Move drm_gem ioctl kerneldoc to uapi file

[David Francis]

The drm_gem ioctls were documented in internal file drm_gem.c
instead of uapi header drm.h. Move them there and change to
appropriate kerneldoc formatting.

Signed-off-by: David Francis <David.Francis@amd.com>
---
 drivers/gpu/drm/drm_gem.c | 30 -----------------------------
 include/uapi/drm/drm.h    | 40 +++++++++++++++++++++++++++------------
 2 files changed, 28 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 3166230d0119..08778a15eefb 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -820,14 +820,6 @@ long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
 }
 EXPORT_SYMBOL(drm_gem_dma_resv_wait);
 
-/**
- * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
- * @dev: drm_device
- * @data: ioctl data
- * @file_priv: drm file-private structure
- *
- * Releases the handle to an mm object.
- */
 int
 drm_gem_close_ioctl(struct drm_device *dev, void *data,
 		    struct drm_file *file_priv)
@@ -843,17 +835,6 @@ drm_gem_close_ioctl(struct drm_device *dev, void *data,
 	return ret;
 }
 
-/**
- * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
- * @dev: drm_device
- * @data: ioctl data
- * @file_priv: drm file-private structure
- *
- * Create a global name for an object, returning the name.
- *
- * Note that the name does not hold a reference; when the object
- * is freed, the name goes away.
- */
 int
 drm_gem_flink_ioctl(struct drm_device *dev, void *data,
 		    struct drm_file *file_priv)
@@ -893,17 +874,6 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
 	return ret;
 }
 
-/**
- * drm_gem_open_ioctl - implementation of the GEM_OPEN ioctl
- * @dev: drm_device
- * @data: ioctl data
- * @file_priv: drm file-private structure
- *
- * Open an object using the global name, returning a handle and the size.
- *
- * This handle (of course) holds a reference to the object, so the object
- * will not go away until the handle is deleted.
- */
 int
 drm_gem_open_ioctl(struct drm_device *dev, void *data,
 		   struct drm_file *file_priv)
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index e3940b657e16..e512da8f3baf 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -597,31 +597,47 @@ struct drm_set_version {
 	int drm_dd_minor;
 };
 
-/* DRM_IOCTL_GEM_CLOSE ioctl argument type */
+/**
+ * struct drm_gem_close - Argument for &DRM_IOCTL_GEM_CLOSE ioctl.
+ * @handle: Handle of the object to be closed.
+ * @pad: Padding.
+ *
+ * Releases the handle to an mm object.
+ */
 struct drm_gem_close {
-	/** Handle of the object to be closed. */
 	__u32 handle;
 	__u32 pad;
 };
 
-/* DRM_IOCTL_GEM_FLINK ioctl argument type */
+/**
+ * struct drm_gem_flink - Argument for &DRM_IOCTL_GEM_FLINK ioctl.
+ * @handle: Handle for the object being named.
+ * @name: Returned global name.
+ *
+ * Create a global name for an object, returning the name.
+ *
+ * Note that the name does not hold a reference; when the object
+ * is freed, the name goes away.
+ */
 struct drm_gem_flink {
-	/** Handle for the object being named */
 	__u32 handle;
-
-	/** Returned global name */
 	__u32 name;
 };
 
-/* DRM_IOCTL_GEM_OPEN ioctl argument type */
+/**
+ * struct drm_gem_open - Argument for &DRM_IOCTL_GEM_OPEN ioctl.
+ * @name: Name of object being opened.
+ * @handle: Returned handle for the object.
+ * @size: Returned size of the object
+ *
+ * Open an object using the global name, returning a handle and the size.
+ *
+ * This handle (of course) holds a reference to the object, so the object
+ * will not go away until the handle is deleted.
+ */
 struct drm_gem_open {
-	/** Name of object being opened */
 	__u32 name;
-
-	/** Returned handle for the object */
 	__u32 handle;
-
-	/** Returned size of the object */
 	__u64 size;
 };
 
-- 
2.34.1

Re: [PATCH 2/2] drm: Move drm_gem ioctl kerneldoc to uapi file

[Simona Vetter]

On Fri, Jul 11, 2025 at 10:53:42AM -0400, David Francis wrote:
> The drm_gem ioctls were documented in internal file drm_gem.c
> instead of uapi header drm.h. Move them there and change to
> appropriate kerneldoc formatting.
> 
> Signed-off-by: David Francis <David.Francis@amd.com>

Thanks a lot for taking care of this!

Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch>

I'll leave review for the first patch to folks who care about criu, but it
looked good to me too.
-Sima

> ---
>  drivers/gpu/drm/drm_gem.c | 30 -----------------------------
>  include/uapi/drm/drm.h    | 40 +++++++++++++++++++++++++++------------
>  2 files changed, 28 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
> index 3166230d0119..08778a15eefb 100644
> --- a/drivers/gpu/drm/drm_gem.c
> +++ b/drivers/gpu/drm/drm_gem.c
> @@ -820,14 +820,6 @@ long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
>  }
>  EXPORT_SYMBOL(drm_gem_dma_resv_wait);
>  
> -/**
> - * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
> - * @dev: drm_device
> - * @data: ioctl data
> - * @file_priv: drm file-private structure
> - *
> - * Releases the handle to an mm object.
> - */
>  int
>  drm_gem_close_ioctl(struct drm_device *dev, void *data,
>  		    struct drm_file *file_priv)
> @@ -843,17 +835,6 @@ drm_gem_close_ioctl(struct drm_device *dev, void *data,
>  	return ret;
>  }
>  
> -/**
> - * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
> - * @dev: drm_device
> - * @data: ioctl data
> - * @file_priv: drm file-private structure
> - *
> - * Create a global name for an object, returning the name.
> - *
> - * Note that the name does not hold a reference; when the object
> - * is freed, the name goes away.
> - */
>  int
>  drm_gem_flink_ioctl(struct drm_device *dev, void *data,
>  		    struct drm_file *file_priv)
> @@ -893,17 +874,6 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
>  	return ret;
>  }
>  
> -/**
> - * drm_gem_open_ioctl - implementation of the GEM_OPEN ioctl
> - * @dev: drm_device
> - * @data: ioctl data
> - * @file_priv: drm file-private structure
> - *
> - * Open an object using the global name, returning a handle and the size.
> - *
> - * This handle (of course) holds a reference to the object, so the object
> - * will not go away until the handle is deleted.
> - */
>  int
>  drm_gem_open_ioctl(struct drm_device *dev, void *data,
>  		   struct drm_file *file_priv)
> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
> index e3940b657e16..e512da8f3baf 100644
> --- a/include/uapi/drm/drm.h
> +++ b/include/uapi/drm/drm.h
> @@ -597,31 +597,47 @@ struct drm_set_version {
>  	int drm_dd_minor;
>  };
>  
> -/* DRM_IOCTL_GEM_CLOSE ioctl argument type */
> +/**
> + * struct drm_gem_close - Argument for &DRM_IOCTL_GEM_CLOSE ioctl.
> + * @handle: Handle of the object to be closed.
> + * @pad: Padding.
> + *
> + * Releases the handle to an mm object.
> + */
>  struct drm_gem_close {
> -	/** Handle of the object to be closed. */
>  	__u32 handle;
>  	__u32 pad;
>  };
>  
> -/* DRM_IOCTL_GEM_FLINK ioctl argument type */
> +/**
> + * struct drm_gem_flink - Argument for &DRM_IOCTL_GEM_FLINK ioctl.
> + * @handle: Handle for the object being named.
> + * @name: Returned global name.
> + *
> + * Create a global name for an object, returning the name.
> + *
> + * Note that the name does not hold a reference; when the object
> + * is freed, the name goes away.
> + */
>  struct drm_gem_flink {
> -	/** Handle for the object being named */
>  	__u32 handle;
> -
> -	/** Returned global name */
>  	__u32 name;
>  };
>  
> -/* DRM_IOCTL_GEM_OPEN ioctl argument type */
> +/**
> + * struct drm_gem_open - Argument for &DRM_IOCTL_GEM_OPEN ioctl.
> + * @name: Name of object being opened.
> + * @handle: Returned handle for the object.
> + * @size: Returned size of the object
> + *
> + * Open an object using the global name, returning a handle and the size.
> + *
> + * This handle (of course) holds a reference to the object, so the object
> + * will not go away until the handle is deleted.
> + */
>  struct drm_gem_open {
> -	/** Name of object being opened */
>  	__u32 name;
> -
> -	/** Returned handle for the object */
>  	__u32 handle;
> -
> -	/** Returned size of the object */
>  	__u64 size;
>  };
>  
> -- 
> 2.34.1
> 

-- 
Simona Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 2/2] drm: Move drm_gem ioctl kerneldoc to uapi file

[Christian König]

On 11.07.25 23:55, Simona Vetter wrote:
> On Fri, Jul 11, 2025 at 10:53:42AM -0400, David Francis wrote:
>> The drm_gem ioctls were documented in internal file drm_gem.c
>> instead of uapi header drm.h. Move them there and change to
>> appropriate kerneldoc formatting.
>>
>> Signed-off-by: David Francis <David.Francis@amd.com>
> 
> Thanks a lot for taking care of this!
> 
> Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch>
> 
> I'll leave review for the first patch to folks who care about criu, but it
> looked good to me too.

I will take that as an Acked-by.

Are you ok that we push this into drm-misc-next by the end of the week when we have the IGT test ready?

The patches for the CRIU code are ready and IIRC there will be a merge request made, but it will take quite a while until they are actually merged I think.

Christian.

> -Sima
> 
>> ---
>>  drivers/gpu/drm/drm_gem.c | 30 -----------------------------
>>  include/uapi/drm/drm.h    | 40 +++++++++++++++++++++++++++------------
>>  2 files changed, 28 insertions(+), 42 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
>> index 3166230d0119..08778a15eefb 100644
>> --- a/drivers/gpu/drm/drm_gem.c
>> +++ b/drivers/gpu/drm/drm_gem.c
>> @@ -820,14 +820,6 @@ long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
>>  }
>>  EXPORT_SYMBOL(drm_gem_dma_resv_wait);
>>  
>> -/**
>> - * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
>> - * @dev: drm_device
>> - * @data: ioctl data
>> - * @file_priv: drm file-private structure
>> - *
>> - * Releases the handle to an mm object.
>> - */
>>  int
>>  drm_gem_close_ioctl(struct drm_device *dev, void *data,
>>  		    struct drm_file *file_priv)
>> @@ -843,17 +835,6 @@ drm_gem_close_ioctl(struct drm_device *dev, void *data,
>>  	return ret;
>>  }
>>  
>> -/**
>> - * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
>> - * @dev: drm_device
>> - * @data: ioctl data
>> - * @file_priv: drm file-private structure
>> - *
>> - * Create a global name for an object, returning the name.
>> - *
>> - * Note that the name does not hold a reference; when the object
>> - * is freed, the name goes away.
>> - */
>>  int
>>  drm_gem_flink_ioctl(struct drm_device *dev, void *data,
>>  		    struct drm_file *file_priv)
>> @@ -893,17 +874,6 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
>>  	return ret;
>>  }
>>  
>> -/**
>> - * drm_gem_open_ioctl - implementation of the GEM_OPEN ioctl
>> - * @dev: drm_device
>> - * @data: ioctl data
>> - * @file_priv: drm file-private structure
>> - *
>> - * Open an object using the global name, returning a handle and the size.
>> - *
>> - * This handle (of course) holds a reference to the object, so the object
>> - * will not go away until the handle is deleted.
>> - */
>>  int
>>  drm_gem_open_ioctl(struct drm_device *dev, void *data,
>>  		   struct drm_file *file_priv)
>> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
>> index e3940b657e16..e512da8f3baf 100644
>> --- a/include/uapi/drm/drm.h
>> +++ b/include/uapi/drm/drm.h
>> @@ -597,31 +597,47 @@ struct drm_set_version {
>>  	int drm_dd_minor;
>>  };
>>  
>> -/* DRM_IOCTL_GEM_CLOSE ioctl argument type */
>> +/**
>> + * struct drm_gem_close - Argument for &DRM_IOCTL_GEM_CLOSE ioctl.
>> + * @handle: Handle of the object to be closed.
>> + * @pad: Padding.
>> + *
>> + * Releases the handle to an mm object.
>> + */
>>  struct drm_gem_close {
>> -	/** Handle of the object to be closed. */
>>  	__u32 handle;
>>  	__u32 pad;
>>  };
>>  
>> -/* DRM_IOCTL_GEM_FLINK ioctl argument type */
>> +/**
>> + * struct drm_gem_flink - Argument for &DRM_IOCTL_GEM_FLINK ioctl.
>> + * @handle: Handle for the object being named.
>> + * @name: Returned global name.
>> + *
>> + * Create a global name for an object, returning the name.
>> + *
>> + * Note that the name does not hold a reference; when the object
>> + * is freed, the name goes away.
>> + */
>>  struct drm_gem_flink {
>> -	/** Handle for the object being named */
>>  	__u32 handle;
>> -
>> -	/** Returned global name */
>>  	__u32 name;
>>  };
>>  
>> -/* DRM_IOCTL_GEM_OPEN ioctl argument type */
>> +/**
>> + * struct drm_gem_open - Argument for &DRM_IOCTL_GEM_OPEN ioctl.
>> + * @name: Name of object being opened.
>> + * @handle: Returned handle for the object.
>> + * @size: Returned size of the object
>> + *
>> + * Open an object using the global name, returning a handle and the size.
>> + *
>> + * This handle (of course) holds a reference to the object, so the object
>> + * will not go away until the handle is deleted.
>> + */
>>  struct drm_gem_open {
>> -	/** Name of object being opened */
>>  	__u32 name;
>> -
>> -	/** Returned handle for the object */
>>  	__u32 handle;
>> -
>> -	/** Returned size of the object */
>>  	__u64 size;
>>  };
>>  
>> -- 
>> 2.34.1
>>
> 

Re: [PATCH 2/2] drm: Move drm_gem ioctl kerneldoc to uapi file

[Simona Vetter]

On Mon, Jul 14, 2025 at 11:50:32AM +0200, Christian König wrote:
> On 11.07.25 23:55, Simona Vetter wrote:
> > On Fri, Jul 11, 2025 at 10:53:42AM -0400, David Francis wrote:
> >> The drm_gem ioctls were documented in internal file drm_gem.c
> >> instead of uapi header drm.h. Move them there and change to
> >> appropriate kerneldoc formatting.
> >>
> >> Signed-off-by: David Francis <David.Francis@amd.com>
> > 
> > Thanks a lot for taking care of this!
> > 
> > Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch>
> > 
> > I'll leave review for the first patch to folks who care about criu, but it
> > looked good to me too.
> 
> I will take that as an Acked-by.
> 
> Are you ok that we push this into drm-misc-next by the end of the week when we have the IGT test ready?

Aye, sounds like a plan.
-Sima

> 
> The patches for the CRIU code are ready and IIRC there will be a merge
> request made, but it will take quite a while until they are actually
> merged I think.

> 
> Christian.
> 
> > -Sima
> > 
> >> ---
> >>  drivers/gpu/drm/drm_gem.c | 30 -----------------------------
> >>  include/uapi/drm/drm.h    | 40 +++++++++++++++++++++++++++------------
> >>  2 files changed, 28 insertions(+), 42 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
> >> index 3166230d0119..08778a15eefb 100644
> >> --- a/drivers/gpu/drm/drm_gem.c
> >> +++ b/drivers/gpu/drm/drm_gem.c
> >> @@ -820,14 +820,6 @@ long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
> >>  }
> >>  EXPORT_SYMBOL(drm_gem_dma_resv_wait);
> >>  
> >> -/**
> >> - * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
> >> - * @dev: drm_device
> >> - * @data: ioctl data
> >> - * @file_priv: drm file-private structure
> >> - *
> >> - * Releases the handle to an mm object.
> >> - */
> >>  int
> >>  drm_gem_close_ioctl(struct drm_device *dev, void *data,
> >>  		    struct drm_file *file_priv)
> >> @@ -843,17 +835,6 @@ drm_gem_close_ioctl(struct drm_device *dev, void *data,
> >>  	return ret;
> >>  }
> >>  
> >> -/**
> >> - * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
> >> - * @dev: drm_device
> >> - * @data: ioctl data
> >> - * @file_priv: drm file-private structure
> >> - *
> >> - * Create a global name for an object, returning the name.
> >> - *
> >> - * Note that the name does not hold a reference; when the object
> >> - * is freed, the name goes away.
> >> - */
> >>  int
> >>  drm_gem_flink_ioctl(struct drm_device *dev, void *data,
> >>  		    struct drm_file *file_priv)
> >> @@ -893,17 +874,6 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
> >>  	return ret;
> >>  }
> >>  
> >> -/**
> >> - * drm_gem_open_ioctl - implementation of the GEM_OPEN ioctl
> >> - * @dev: drm_device
> >> - * @data: ioctl data
> >> - * @file_priv: drm file-private structure
> >> - *
> >> - * Open an object using the global name, returning a handle and the size.
> >> - *
> >> - * This handle (of course) holds a reference to the object, so the object
> >> - * will not go away until the handle is deleted.
> >> - */
> >>  int
> >>  drm_gem_open_ioctl(struct drm_device *dev, void *data,
> >>  		   struct drm_file *file_priv)
> >> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
> >> index e3940b657e16..e512da8f3baf 100644
> >> --- a/include/uapi/drm/drm.h
> >> +++ b/include/uapi/drm/drm.h
> >> @@ -597,31 +597,47 @@ struct drm_set_version {
> >>  	int drm_dd_minor;
> >>  };
> >>  
> >> -/* DRM_IOCTL_GEM_CLOSE ioctl argument type */
> >> +/**
> >> + * struct drm_gem_close - Argument for &DRM_IOCTL_GEM_CLOSE ioctl.
> >> + * @handle: Handle of the object to be closed.
> >> + * @pad: Padding.
> >> + *
> >> + * Releases the handle to an mm object.
> >> + */
> >>  struct drm_gem_close {
> >> -	/** Handle of the object to be closed. */
> >>  	__u32 handle;
> >>  	__u32 pad;
> >>  };
> >>  
> >> -/* DRM_IOCTL_GEM_FLINK ioctl argument type */
> >> +/**
> >> + * struct drm_gem_flink - Argument for &DRM_IOCTL_GEM_FLINK ioctl.
> >> + * @handle: Handle for the object being named.
> >> + * @name: Returned global name.
> >> + *
> >> + * Create a global name for an object, returning the name.
> >> + *
> >> + * Note that the name does not hold a reference; when the object
> >> + * is freed, the name goes away.
> >> + */
> >>  struct drm_gem_flink {
> >> -	/** Handle for the object being named */
> >>  	__u32 handle;
> >> -
> >> -	/** Returned global name */
> >>  	__u32 name;
> >>  };
> >>  
> >> -/* DRM_IOCTL_GEM_OPEN ioctl argument type */
> >> +/**
> >> + * struct drm_gem_open - Argument for &DRM_IOCTL_GEM_OPEN ioctl.
> >> + * @name: Name of object being opened.
> >> + * @handle: Returned handle for the object.
> >> + * @size: Returned size of the object
> >> + *
> >> + * Open an object using the global name, returning a handle and the size.
> >> + *
> >> + * This handle (of course) holds a reference to the object, so the object
> >> + * will not go away until the handle is deleted.
> >> + */
> >>  struct drm_gem_open {
> >> -	/** Name of object being opened */
> >>  	__u32 name;
> >> -
> >> -	/** Returned handle for the object */
> >>  	__u32 handle;
> >> -
> >> -	/** Returned size of the object */
> >>  	__u64 size;
> >>  };
> >>  
> >> -- 
> >> 2.34.1
> >>
> > 
> 

-- 
Simona Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

RE: [PATCH 1/2] drm: Add DRM prime interface to reassign GEM handle

[Zhang, Jesse(Jie)]

[AMD Official Use Only - AMD Internal Distribution Only]

-----Original Message-----
From: dri-devel <dri-devel-bounces@lists.freedesktop.org> On Behalf Of David Francis
Sent: Friday, July 11, 2025 10:54 PM
To: dri-devel@lists.freedesktop.org
Cc: tvrtko.ursulin@igalia.com; Kuehling, Felix <Felix.Kuehling@amd.com>; Yat Sin, David <David.YatSin@amd.com>; Freehill, Chris <Chris.Freehill@amd.com>; Koenig, Christian <Christian.Koenig@amd.com>; dcostantino@meta.com; sruffell@meta.com; simona@ffwll.ch; mripard@kernel.org; tzimmermann@suse.de; Francis, David <David.Francis@amd.com>
Subject: [PATCH 1/2] drm: Add DRM prime interface to reassign GEM handle

CRIU restore of drm buffer objects requires the ability to create or import a buffer object with a specific gem handle.

Add new drm ioctl DRM_IOCTL_GEM_CHANGE_HANDLE, which takes the gem handle of an object and moves that object to a specified new gem handle.

This ioctl needs to call drm_prime_remove_buf_handle, but that function acquires the prime lock, which the ioctl needs to hold for other purposes.

Make drm_prime_remove_buf_handle not acquire the prime lock, and change its other caller to reflect this.

The rest of the kernel patches required to enable CRIU can be found at https://lore.kernel.org/dri-devel/20250617194536.538681-1-David.Francis@amd.com/

Signed-off-by: David Francis <David.Francis@amd.com>
---
 drivers/gpu/drm/drm_gem.c      | 54 ++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_internal.h |  4 +++
 drivers/gpu/drm/drm_ioctl.c    |  1 +
 drivers/gpu/drm/drm_prime.c    |  6 +---
 include/uapi/drm/drm.h         | 23 +++++++++++++++
 5 files changed, 83 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index c6240bab3fa5..3166230d0119 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -282,7 +282,12 @@ drm_gem_object_release_handle(int id, void *ptr, void *data)
        if (obj->funcs->close)
                obj->funcs->close(obj, file_priv);

+       mutex_lock(&file_priv->prime.lock);
+
        drm_prime_remove_buf_handle(&file_priv->prime, id);
+
+       mutex_unlock(&file_priv->prime.lock);
+
        drm_vma_node_revoke(&obj->vma_node, file_priv);

        drm_gem_object_handle_put_unlocked(obj);
@@ -933,6 +938,55 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data,
        return ret;
 }

+int drm_gem_change_handle_ioctl(struct drm_device *dev, void *data,
+                               struct drm_file *file_priv)
+{
+       struct drm_gem_change_handle *args = data;
+       struct drm_gem_object *obj;
+       int ret;
+
+       if (!drm_core_check_feature(dev, DRIVER_GEM))
+               return -EOPNOTSUPP;
+
+       obj = drm_gem_object_lookup(file_priv, args->handle);
+       if (!obj)
+               return -ENOENT;
+
+       if (args->handle == args->new_handle)
+               return 0;
+
+       mutex_lock(&file_priv->prime.lock);
+
+       spin_lock(&file_priv->table_lock);
+       ret = idr_alloc(&file_priv->object_idr, obj,
+               args->new_handle, args->new_handle + 1, GFP_NOWAIT);
+       spin_unlock(&file_priv->table_lock);
+
+       if (ret < 0)
+               goto out_unlock;
+
+       if (obj->dma_buf) {
+               ret = drm_prime_add_buf_handle(&file_priv->prime, obj->dma_buf, args->new_handle);
+               if (ret < 0) {
+                       spin_lock(&file_priv->table_lock);
+                       idr_remove(&file_priv->object_idr, args->new_handle);
+                       spin_unlock(&file_priv->table_lock);
+                       goto out_unlock;
+               }
+
+               drm_prime_remove_buf_handle(&file_priv->prime, args->handle);
+       }
+
           Added ret = 0 before out_unlock to ensure proper return value
        ret = 0;

        Thanks
        Jesse
+       spin_lock(&file_priv->table_lock);
+       idr_remove(&file_priv->object_idr, args->handle);
+       spin_unlock(&file_priv->table_lock);
+
+out_unlock:
+       mutex_unlock(&file_priv->prime.lock);
+
+       return ret;
+}
+
 /**
  * drm_gem_open - initializes GEM file-private structures at devnode open time
  * @dev: drm_device which is being opened by userspace diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h index b2b6a8e49dda..e9d5cdf7e033 100644
--- a/drivers/gpu/drm/drm_internal.h
+++ b/drivers/gpu/drm/drm_internal.h
@@ -85,6 +85,8 @@ int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data,

 void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv);  void drm_prime_destroy_file_private(struct drm_prime_file_private *prime_fpriv);
+int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
+                            struct dma_buf *dma_buf, uint32_t handle);
 void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
                                 uint32_t handle);

@@ -168,6 +170,8 @@ int drm_gem_close_ioctl(struct drm_device *dev, void *data,
                        struct drm_file *file_priv);
 int drm_gem_flink_ioctl(struct drm_device *dev, void *data,
                        struct drm_file *file_priv);
+int drm_gem_change_handle_ioctl(struct drm_device *dev, void *data,
+                               struct drm_file *file_priv);
 int drm_gem_open_ioctl(struct drm_device *dev, void *data,
                       struct drm_file *file_priv);
 void drm_gem_open(struct drm_device *dev, struct drm_file *file_private); diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index f593dc569d31..d8a24875a7ba 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -653,6 +653,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
        DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
        DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
+       DRM_IOCTL_DEF(DRM_IOCTL_GEM_CHANGE_HANDLE,
+drm_gem_change_handle_ioctl, DRM_RENDER_ALLOW),

        DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index bdb51c8f262e..1f2e858e5000 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -93,7 +93,7 @@ struct drm_prime_member {
        struct rb_node handle_rb;
 };

-static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
+int drm_prime_add_buf_handle(struct drm_prime_file_private
+*prime_fpriv,
                                    struct dma_buf *dma_buf, uint32_t handle)  {
        struct drm_prime_member *member;
@@ -190,8 +190,6 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,  {
        struct rb_node *rb;

-       mutex_lock(&prime_fpriv->lock);
-
        rb = prime_fpriv->handles.rb_node;
        while (rb) {
                struct drm_prime_member *member;
@@ -210,8 +208,6 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
                        rb = rb->rb_left;
                }
        }
-
-       mutex_unlock(&prime_fpriv->lock);
 }

 void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv) diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 7fba37b94401..e3940b657e16 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -625,6 +625,21 @@ struct drm_gem_open {
        __u64 size;
 };

+/**
+ * struct drm_gem_change_handle - Argument for &DRM_IOCTL_GEM_CHANGE_HANDLE ioctl.
+ * @handle: The handle of a gem object.
+ * @new_handle: An available gem handle.
+ *
+ * This ioctl changes the handle of a GEM object to the specified one.
+ * The new handle must be unused. On success the old handle is closed
+ * and all further IOCTL should refer to the new handle only.
+ * Calls to DRM_IOCTL_PRIME_FD_TO_HANDLE will return the new handle.
+ */
+struct drm_gem_change_handle {
+       __u32 handle;
+       __u32 new_handle;
+};
+
 /**
  * DRM_CAP_DUMB_BUFFER
  *
@@ -1305,6 +1320,14 @@ extern "C" {
  */
 #define DRM_IOCTL_SET_CLIENT_NAME      DRM_IOWR(0xD1, struct drm_set_client_name)

+/**
+ * DRM_IOCTL_GEM_CHANGE_HANDLE - Move an object to a different handle
+ *
+ * Some applications (notably CRIU) need objects to have specific gem handles.
+ * This ioctl changes the object at one gem handle to use a new gem handle.
+ */
+#define DRM_IOCTL_GEM_CHANGE_HANDLE    DRM_IOWR(0xD2, struct drm_gem_change_handle)
+
 /*
  * Device specific ioctls should only be in their respective headers
  * The device specific ioctl range is from 0x40 to 0x9f.
--
2.34.1

Re: [PATCH 2/2] drm: Move drm_gem ioctl kerneldoc to uapi file

[Christian König]

On 14.07.25 14:40, Simona Vetter wrote:
> On Mon, Jul 14, 2025 at 11:50:32AM +0200, Christian König wrote:
>> On 11.07.25 23:55, Simona Vetter wrote:
>>> On Fri, Jul 11, 2025 at 10:53:42AM -0400, David Francis wrote:
>>>> The drm_gem ioctls were documented in internal file drm_gem.c
>>>> instead of uapi header drm.h. Move them there and change to
>>>> appropriate kerneldoc formatting.
>>>>
>>>> Signed-off-by: David Francis <David.Francis@amd.com>
>>>
>>> Thanks a lot for taking care of this!
>>>
>>> Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch>
>>>
>>> I'll leave review for the first patch to folks who care about criu, but it
>>> looked good to me too.
>>
>> I will take that as an Acked-by.
>>
>> Are you ok that we push this into drm-misc-next by the end of the week when we have the IGT test ready?
> 
> Aye, sounds like a plan.

Added the reviews, acks and links to the cover letter to the v2 from this morning and pushed the result to drm-misc-next.

We just haven't been quick enough with the IGT test (which BTW found another bug) to push it earlier.

Fingers crossed that there will be another misc-next pull request before 6.17-rc1.

Regards,
Christian.

> -Sima
> 
>>
>> The patches for the CRIU code are ready and IIRC there will be a merge
>> request made, but it will take quite a while until they are actually
>> merged I think.
> 
>>
>> Christian.
>>
>>> -Sima
>>>
>>>> ---
>>>>  drivers/gpu/drm/drm_gem.c | 30 -----------------------------
>>>>  include/uapi/drm/drm.h    | 40 +++++++++++++++++++++++++++------------
>>>>  2 files changed, 28 insertions(+), 42 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
>>>> index 3166230d0119..08778a15eefb 100644
>>>> --- a/drivers/gpu/drm/drm_gem.c
>>>> +++ b/drivers/gpu/drm/drm_gem.c
>>>> @@ -820,14 +820,6 @@ long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
>>>>  }
>>>>  EXPORT_SYMBOL(drm_gem_dma_resv_wait);
>>>>  
>>>> -/**
>>>> - * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
>>>> - * @dev: drm_device
>>>> - * @data: ioctl data
>>>> - * @file_priv: drm file-private structure
>>>> - *
>>>> - * Releases the handle to an mm object.
>>>> - */
>>>>  int
>>>>  drm_gem_close_ioctl(struct drm_device *dev, void *data,
>>>>  		    struct drm_file *file_priv)
>>>> @@ -843,17 +835,6 @@ drm_gem_close_ioctl(struct drm_device *dev, void *data,
>>>>  	return ret;
>>>>  }
>>>>  
>>>> -/**
>>>> - * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
>>>> - * @dev: drm_device
>>>> - * @data: ioctl data
>>>> - * @file_priv: drm file-private structure
>>>> - *
>>>> - * Create a global name for an object, returning the name.
>>>> - *
>>>> - * Note that the name does not hold a reference; when the object
>>>> - * is freed, the name goes away.
>>>> - */
>>>>  int
>>>>  drm_gem_flink_ioctl(struct drm_device *dev, void *data,
>>>>  		    struct drm_file *file_priv)
>>>> @@ -893,17 +874,6 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data,
>>>>  	return ret;
>>>>  }
>>>>  
>>>> -/**
>>>> - * drm_gem_open_ioctl - implementation of the GEM_OPEN ioctl
>>>> - * @dev: drm_device
>>>> - * @data: ioctl data
>>>> - * @file_priv: drm file-private structure
>>>> - *
>>>> - * Open an object using the global name, returning a handle and the size.
>>>> - *
>>>> - * This handle (of course) holds a reference to the object, so the object
>>>> - * will not go away until the handle is deleted.
>>>> - */
>>>>  int
>>>>  drm_gem_open_ioctl(struct drm_device *dev, void *data,
>>>>  		   struct drm_file *file_priv)
>>>> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
>>>> index e3940b657e16..e512da8f3baf 100644
>>>> --- a/include/uapi/drm/drm.h
>>>> +++ b/include/uapi/drm/drm.h
>>>> @@ -597,31 +597,47 @@ struct drm_set_version {
>>>>  	int drm_dd_minor;
>>>>  };
>>>>  
>>>> -/* DRM_IOCTL_GEM_CLOSE ioctl argument type */
>>>> +/**
>>>> + * struct drm_gem_close - Argument for &DRM_IOCTL_GEM_CLOSE ioctl.
>>>> + * @handle: Handle of the object to be closed.
>>>> + * @pad: Padding.
>>>> + *
>>>> + * Releases the handle to an mm object.
>>>> + */
>>>>  struct drm_gem_close {
>>>> -	/** Handle of the object to be closed. */
>>>>  	__u32 handle;
>>>>  	__u32 pad;
>>>>  };
>>>>  
>>>> -/* DRM_IOCTL_GEM_FLINK ioctl argument type */
>>>> +/**
>>>> + * struct drm_gem_flink - Argument for &DRM_IOCTL_GEM_FLINK ioctl.
>>>> + * @handle: Handle for the object being named.
>>>> + * @name: Returned global name.
>>>> + *
>>>> + * Create a global name for an object, returning the name.
>>>> + *
>>>> + * Note that the name does not hold a reference; when the object
>>>> + * is freed, the name goes away.
>>>> + */
>>>>  struct drm_gem_flink {
>>>> -	/** Handle for the object being named */
>>>>  	__u32 handle;
>>>> -
>>>> -	/** Returned global name */
>>>>  	__u32 name;
>>>>  };
>>>>  
>>>> -/* DRM_IOCTL_GEM_OPEN ioctl argument type */
>>>> +/**
>>>> + * struct drm_gem_open - Argument for &DRM_IOCTL_GEM_OPEN ioctl.
>>>> + * @name: Name of object being opened.
>>>> + * @handle: Returned handle for the object.
>>>> + * @size: Returned size of the object
>>>> + *
>>>> + * Open an object using the global name, returning a handle and the size.
>>>> + *
>>>> + * This handle (of course) holds a reference to the object, so the object
>>>> + * will not go away until the handle is deleted.
>>>> + */
>>>>  struct drm_gem_open {
>>>> -	/** Name of object being opened */
>>>>  	__u32 name;
>>>> -
>>>> -	/** Returned handle for the object */
>>>>  	__u32 handle;
>>>> -
>>>> -	/** Returned size of the object */
>>>>  	__u64 size;
>>>>  };
>>>>  
>>>> -- 
>>>> 2.34.1
>>>>
>>>
>>
>