drm/panthor: Add driver IOCTL for setting BO labels

Allow UM to label a BO for which it possesses a DRM handle.

Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20250423021238.1639175-3-adrian.larumbe@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index 4d4a52a033f6583a5898cb4ede14196cd1b46aa7..32c956d4c3662549af9dd50de1a8f56e85e52966 100644 (file)
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1338,6 +1338,46 @@ static int panthor_ioctl_vm_get_state(struct drm_device *ddev, void *data,
        return 0;
 }
 
+static int panthor_ioctl_bo_set_label(struct drm_device *ddev, void *data,
+                                     struct drm_file *file)
+{
+       struct drm_panthor_bo_set_label *args = data;
+       struct drm_gem_object *obj;
+       const char *label = NULL;
+       int ret = 0;
+
+       if (args->pad)
+               return -EINVAL;
+
+       obj = drm_gem_object_lookup(file, args->handle);
+       if (!obj)
+               return -ENOENT;
+
+       if (args->label) {
+               label = strndup_user((const char __user *)(uintptr_t)args->label,
+                                    PANTHOR_BO_LABEL_MAXLEN);
+               if (IS_ERR(label)) {
+                       ret = PTR_ERR(label);
+                       if (ret == -EINVAL)
+                               ret = -E2BIG;
+                       goto err_put_obj;
+               }
+       }
+
+       /*
+        * We treat passing a label of length 0 and passing a NULL label
+        * differently, because even though they might seem conceptually
+        * similar, future uses of the BO label might expect a different
+        * behaviour in each case.
+        */
+       panthor_gem_bo_set_label(obj, label);
+
+err_put_obj:
+       drm_gem_object_put(obj);
+
+       return ret;
+}
+
 static int
 panthor_open(struct drm_device *ddev, struct drm_file *file)
 {
@@ -1407,6 +1447,7 @@ static const struct drm_ioctl_desc panthor_drm_driver_ioctls[] = {
        PANTHOR_IOCTL(TILER_HEAP_CREATE, tiler_heap_create, DRM_RENDER_ALLOW),
        PANTHOR_IOCTL(TILER_HEAP_DESTROY, tiler_heap_destroy, DRM_RENDER_ALLOW),
        PANTHOR_IOCTL(GROUP_SUBMIT, group_submit, DRM_RENDER_ALLOW),
+       PANTHOR_IOCTL(BO_SET_LABEL, bo_set_label, DRM_RENDER_ALLOW),
 };
 
 static int panthor_mmap(struct file *filp, struct vm_area_struct *vma)
@@ -1516,6 +1557,7 @@ static void panthor_debugfs_init(struct drm_minor *minor)
  * - 1.2 - adds DEV_QUERY_GROUP_PRIORITIES_INFO query
  *       - adds PANTHOR_GROUP_PRIORITY_REALTIME priority
  * - 1.3 - adds DRM_PANTHOR_GROUP_STATE_INNOCENT flag
+ * - 1.4 - adds DRM_IOCTL_PANTHOR_BO_SET_LABEL ioctl
  */
 static const struct drm_driver panthor_drm_driver = {
        .driver_features = DRIVER_RENDER | DRIVER_GEM | DRIVER_SYNCOBJ |
@@ -1529,7 +1571,7 @@ static const struct drm_driver panthor_drm_driver = {
        .name = "panthor",
        .desc = "Panthor DRM driver",
        .major = 1,
-       .minor = 3,
+       .minor = 4,
 
        .gem_create_object = panthor_gem_create_object,
        .gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table,

diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h
index af0d77338860c903375b72bc5d1d3a16d12bc196..983cc8ca264e1de2cca2e93c99f9d31f79aa8ced 100644 (file)
--- a/drivers/gpu/drm/panthor/panthor_gem.h
+++ b/drivers/gpu/drm/panthor/panthor_gem.h
@@ -13,6 +13,8 @@
 
 struct panthor_vm;
 
+#define PANTHOR_BO_LABEL_MAXLEN        4096
+
 /**
  * struct panthor_gem_object - Driver specific GEM object.
  */

diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
index 97e2c4510e695485191cf01a6cd6a3b73e9a73de..ad9a70afea6c270e0d5c2c3f8e6433ab3dc57e2a 100644 (file)
--- a/include/uapi/drm/panthor_drm.h
+++ b/include/uapi/drm/panthor_drm.h
@@ -127,6 +127,9 @@ enum drm_panthor_ioctl_id {
 
        /** @DRM_PANTHOR_TILER_HEAP_DESTROY: Destroy a tiler heap. */
        DRM_PANTHOR_TILER_HEAP_DESTROY,
+
+       /** @DRM_PANTHOR_BO_SET_LABEL: Label a BO. */
+       DRM_PANTHOR_BO_SET_LABEL,
 };
 
 /**
@@ -977,6 +980,24 @@ struct drm_panthor_tiler_heap_destroy {
        __u32 pad;
 };
 
+/**
+ * struct drm_panthor_bo_set_label - Arguments passed to DRM_IOCTL_PANTHOR_BO_SET_LABEL
+ */
+struct drm_panthor_bo_set_label {
+       /** @handle: Handle of the buffer object to label. */
+       __u32 handle;
+
+       /**  @pad: MBZ. */
+       __u32 pad;
+
+       /**
+        * @label: User pointer to a NUL-terminated string
+        *
+        * Length cannot be greater than 4096
+        */
+       __u64 label;
+};
+
 /**
  * DRM_IOCTL_PANTHOR() - Build a Panthor IOCTL number
  * @__access: Access type. Must be R, W or RW.
@@ -1019,6 +1040,8 @@ enum {
                DRM_IOCTL_PANTHOR(WR, TILER_HEAP_CREATE, tiler_heap_create),
        DRM_IOCTL_PANTHOR_TILER_HEAP_DESTROY =
                DRM_IOCTL_PANTHOR(WR, TILER_HEAP_DESTROY, tiler_heap_destroy),
+       DRM_IOCTL_PANTHOR_BO_SET_LABEL =
+               DRM_IOCTL_PANTHOR(WR, BO_SET_LABEL, bo_set_label),
 };
 
 #if defined(__cplusplus)