[v3,4/5] drm/i915: ttm backend dont provide mmap_offset for kernel buffers

Commit Message

Bob Beckett April 12, 2022, 7:38 p.m. UTC

stolen/kernel buffers should not be mmapable by userland.
do not provide callbacks to facilitate this for these buffers.

Signed-off-by: Robert Beckett <[e-mail]>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 32 +++++++++++++++++++++----
 1 file changed, 27 insertions(+), 5 deletions(-)

Patch

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index a878910a563c..b20f81836c54 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -1092,8 +1092,8 @@  static void i915_ttm_unmap_virtual(struct drm_i915_gem_object *obj)
 	ttm_bo_unmap_virtual(i915_gem_to_ttm(obj));
 }
 
-static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
-	.name = "i915_gem_object_ttm",
+static const struct drm_i915_gem_object_ops i915_gem_ttm_user_obj_ops = {
+	.name = "i915_gem_object_ttm_user",
 	.flags = I915_GEM_OBJECT_IS_SHRINKABLE |
 		 I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
 
@@ -1111,6 +1111,21 @@  static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
 	.mmap_ops = &vm_ops_ttm,
 };
 
+static const struct drm_i915_gem_object_ops i915_gem_ttm_kern_obj_ops = {
+	.name = "i915_gem_object_ttm_kern",
+	.flags = I915_GEM_OBJECT_IS_SHRINKABLE |
+		 I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
+
+	.get_pages = i915_ttm_get_pages,
+	.put_pages = i915_ttm_put_pages,
+	.truncate = i915_ttm_truncate,
+	.shrink = i915_ttm_shrink,
+
+	.adjust_lru = i915_ttm_adjust_lru,
+	.delayed_free = i915_ttm_delayed_free,
+	.migrate = i915_ttm_migrate,
+};
+
 void i915_ttm_bo_destroy(struct ttm_buffer_object *bo)
 {
 	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
@@ -1165,10 +1180,19 @@  int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
 		.no_wait_gpu = false,
 	};
 	enum ttm_bo_type bo_type;
+	const struct drm_i915_gem_object_ops *ops;
 	int ret;
 
 	drm_gem_private_object_init(&i915->drm, &obj->base, size);
-	i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags);
+
+	if (flags & I915_BO_ALLOC_USER && intel_region_to_ttm_type(mem) != I915_PL_STOLEN) {
+		bo_type = ttm_bo_type_device;
+		ops = &i915_gem_ttm_user_obj_ops;
+	} else {
+		bo_type = ttm_bo_type_kernel;
+		ops = &i915_gem_ttm_kern_obj_ops;
+	}
+	i915_gem_object_init(obj, ops, &lock_class, flags);
 
 	obj->bo_offset = offset;
 
@@ -1178,8 +1202,6 @@  int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
 
 	INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN);
 	mutex_init(&obj->ttm.get_io_page.lock);
-	bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :
-		ttm_bo_type_kernel;
 
 	obj->base.vma_node.driver_private = i915_gem_to_ttm(obj);