2022-04-29 21:32:25

by Robert Beckett

Subject: [PATCH v5 4/6] drm/i915: ttm backend dont provide mmap_offset for kernel buffers

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

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

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 4c25d9b2f138..d22a1af214ce 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -1120,8 +1120,8 @@ 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,

@@ -1139,6 +1139,21 @@ 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);
@@ -1193,10 +1208,19 @@ 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;

@@ -1206,8 +1230,6 @@ 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);

--
2.25.1