[RFC,022/162] drm/i915: Reject more ioctls for userptr

Commit Message

Matthew Auld Nov. 27, 2020, 12:04 p.m. UTC

From: Maarten Lankhorst <[e-mail]>

There are a couple of ioctl's related to tiling and cache placement,
that make no sense for userptr, reject those:
- i915_gem_set_tiling_ioctl()
    Tiling should always be linear for userptr. Changing placement will
    fail with -ENXIO.
- i915_gem_set_caching_ioctl()
    Userptr memory should always be cached. Changing will fail with
    -ENXIO.
- i915_gem_set_domain_ioctl()
    Changed to be equivalent to gem_wait, which is correct for the
    cached linear userptr pointers. This is required because we
    cannot grab a reference to the pages in the rework, but waiting
    for idle will do the same.
Still needs an ack from relevant userspace that it won't break,
but should be good.

Signed-off-by: Maarten Lankhorst <[e-mail]>
Cc: Thomas Hellström <[e-mail]>
---
 drivers/gpu/drm/i915/display/intel_display.c | 2 +-
 drivers/gpu/drm/i915/gem/i915_gem_domain.c   | 4 +++-
 drivers/gpu/drm/i915/gem/i915_gem_object.h   | 6 ++++++
 drivers/gpu/drm/i915/gem/i915_gem_userptr.c  | 3 ++-
 4 files changed, 12 insertions(+), 3 deletions(-)

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index ba26545392bc..f36921a3c4bc 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -17854,7 +17854,7 @@  static int intel_user_framebuffer_create_handle(struct drm_framebuffer *fb,
 	struct drm_i915_gem_object *obj = intel_fb_obj(fb);
 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 
-	if (obj->userptr.mm) {
+	if (i915_gem_object_is_userptr(obj)) {
 		drm_dbg(&i915->drm,
 			"attempting to use a userptr for a framebuffer, denied\n");
 		return -EINVAL;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_domain.c b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
index fcce6909f201..c1d4bf62b3ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_domain.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
@@ -528,7 +528,9 @@  i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 	 * considered to be outside of any cache domain.
 	 */
 	if (i915_gem_object_is_proxy(obj)) {
-		err = -ENXIO;
+		/* silently allow userptr to complete */
+		if (!i915_gem_object_is_userptr(obj))
+			err = -ENXIO;
 		goto out;
 	}
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 47da3aff2a79..95907b8eb4c4 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -551,6 +551,12 @@  void __i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj,
 void __i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
 					      enum fb_op_origin origin);
 
+static inline bool
+i915_gem_object_is_userptr(struct drm_i915_gem_object *obj)
+{
+	return obj->userptr.mm;
+}
+
 static inline void
 i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj,
 				  enum fb_op_origin origin)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
index 44af6265948d..64a946d5f753 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
@@ -721,7 +721,8 @@  static const struct drm_i915_gem_object_ops i915_gem_userptr_ops = {
 	.name = "i915_gem_object_userptr",
 	.flags = I915_GEM_OBJECT_IS_SHRINKABLE |
 		 I915_GEM_OBJECT_NO_MMAP |
-		 I915_GEM_OBJECT_ASYNC_CANCEL,
+		 I915_GEM_OBJECT_ASYNC_CANCEL |
+		 I915_GEM_OBJECT_IS_PROXY,
 	.get_pages = i915_gem_userptr_get_pages,
 	.put_pages = i915_gem_userptr_put_pages,
 	.dmabuf_export = i915_gem_userptr_dmabuf_export,