drm/i915/gem: Use shrinkable status for unknown swizzle quirks

Give obj->mm.quirked a name much more reflective of its purpose
(i915_gem_object_has_tiling_quirk) and move it from the obj->mm field as
it doesn't denote a quirk of the backing store, but a quirk in the
object in its treatment of the backing pages, similar to tiling modes.

Then instead of abusing the pinned status of the buffer to protect it
from the shrinker, we can instead hide the buffer from the shrinker so
it is never considered for being swapped.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210119214336.1463-4-chris@chris-wilson.co.uk

7 files changed, 48 insertions, 32 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 689b61c28754..0450795e0d80 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -188,6 +188,24 @@ i915_gem_object_set_volatile(struct drm_i915_gem_object *obj)
 }
 
 static inline bool
+i915_gem_object_has_tiling_quirk(struct drm_i915_gem_object *obj)
+{
+	return test_bit(I915_TILING_QUIRK_BIT, &obj->flags);
+}
+
+static inline void
+i915_gem_object_set_tiling_quirk(struct drm_i915_gem_object *obj)
+{
+	set_bit(I915_TILING_QUIRK_BIT, &obj->flags);
+}
+
+static inline void
+i915_gem_object_clear_tiling_quirk(struct drm_i915_gem_object *obj)
+{
+	clear_bit(I915_TILING_QUIRK_BIT, &obj->flags);
+}
+
+static inline bool
 i915_gem_object_type_has(const struct drm_i915_gem_object *obj,
 			 unsigned long flags)
 {
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index 217151c18d49..0438e00d4ca7 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -173,6 +173,7 @@ struct drm_i915_gem_object {
 #define I915_BO_ALLOC_VOLATILE   BIT(1)
 #define I915_BO_ALLOC_FLAGS (I915_BO_ALLOC_CONTIGUOUS | I915_BO_ALLOC_VOLATILE)
 #define I915_BO_READONLY         BIT(2)
+#define I915_TILING_QUIRK_BIT    3 /* unknown swizzling; do not release! */
 
 	/*
 	 * Is the object to be mapped as read-only to the GPU
@@ -281,12 +282,6 @@ struct drm_i915_gem_object {
 		 * pages were last acquired.
 		 */
 		bool dirty:1;
-
-		/**
-		 * This is set if the object has been pinned due to unknown
-		 * swizzling.
-		 */
-		bool quirked:1;
 	} mm;
 
 	/** Record of address bit 17 of each page at last unbind. */
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
index 3db3c667c486..43028f3539a6 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -16,6 +16,7 @@ void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
 {
 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	unsigned long supported = INTEL_INFO(i915)->page_sizes;
+	bool shrinkable;
 	int i;
 
 	lockdep_assert_held(&obj->mm.lock);
@@ -38,13 +39,6 @@ void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
 
 	obj->mm.pages = pages;
 
-	if (i915_gem_object_is_tiled(obj) &&
-	    i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
-		GEM_BUG_ON(obj->mm.quirked);
-		__i915_gem_object_pin_pages(obj);
-		obj->mm.quirked = true;
-	}
-
 	GEM_BUG_ON(!sg_page_sizes);
 	obj->mm.page_sizes.phys = sg_page_sizes;
 
@@ -63,7 +57,16 @@ void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
 	}
 	GEM_BUG_ON(!HAS_PAGE_SIZES(i915, obj->mm.page_sizes.sg));
 
-	if (i915_gem_object_is_shrinkable(obj)) {
+	shrinkable = i915_gem_object_is_shrinkable(obj);
+
+	if (i915_gem_object_is_tiled(obj) &&
+	    i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
+		GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj));
+		i915_gem_object_set_tiling_quirk(obj);
+		shrinkable = false;
+	}
+
+	if (shrinkable) {
 		struct list_head *list;
 		unsigned long flags;
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
index 3bb65a1b1d93..3c0b157e2a35 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
@@ -227,7 +227,7 @@ int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)
 		goto err_unlock;
 	}
 
-	if (obj->mm.quirked) {
+	if (i915_gem_object_has_tiling_quirk(obj)) {
 		err = -EFAULT;
 		goto err_unlock;
 	}
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_tiling.c b/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
index ffcaee74a249..d589d3d81085 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
@@ -270,14 +270,14 @@ i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
 	    obj->mm.madv == I915_MADV_WILLNEED &&
 	    i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
 		if (tiling == I915_TILING_NONE) {
-			GEM_BUG_ON(!obj->mm.quirked);
-			__i915_gem_object_unpin_pages(obj);
-			obj->mm.quirked = false;
+			GEM_BUG_ON(!i915_gem_object_has_tiling_quirk(obj));
+			i915_gem_object_clear_tiling_quirk(obj);
+			i915_gem_object_make_shrinkable(obj);
 		}
 		if (!i915_gem_object_is_tiled(obj)) {
-			GEM_BUG_ON(obj->mm.quirked);
-			__i915_gem_object_pin_pages(obj);
-			obj->mm.quirked = true;
+			GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj));
+			i915_gem_object_make_unshrinkable(obj);
+			i915_gem_object_set_tiling_quirk(obj);
 		}
 	}
 	mutex_unlock(&obj->mm.lock);
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index d3a287bf56c5..9b04dff5eb32 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -957,14 +957,14 @@ i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
 	    i915_gem_object_is_tiled(obj) &&
 	    i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
 		if (obj->mm.madv == I915_MADV_WILLNEED) {
-			GEM_BUG_ON(!obj->mm.quirked);
-			__i915_gem_object_unpin_pages(obj);
-			obj->mm.quirked = false;
+			GEM_BUG_ON(!i915_gem_object_has_tiling_quirk(obj));
+			i915_gem_object_clear_tiling_quirk(obj);
+			i915_gem_object_make_shrinkable(obj);
 		}
 		if (args->madv == I915_MADV_WILLNEED) {
-			GEM_BUG_ON(obj->mm.quirked);
-			__i915_gem_object_pin_pages(obj);
-			obj->mm.quirked = true;
+			GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj));
+			i915_gem_object_make_unshrinkable(obj);
+			i915_gem_object_set_tiling_quirk(obj);
 		}
 	}
 
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
index 3512bb8433cf..f99bb0113726 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
@@ -38,8 +38,8 @@ static void quirk_add(struct drm_i915_gem_object *obj,
 		      struct list_head *objects)
 {
 	/* quirk is only for live tiled objects, use it to declare ownership */
-	GEM_BUG_ON(obj->mm.quirked);
-	obj->mm.quirked = true;
+	GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj));
+	i915_gem_object_set_tiling_quirk(obj);
 	list_add(&obj->st_link, objects);
 }
 
@@ -85,7 +85,7 @@ static void unpin_ggtt(struct i915_ggtt *ggtt)
 	struct i915_vma *vma;
 
 	list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link)
-		if (vma->obj->mm.quirked)
+		if (i915_gem_object_has_tiling_quirk(vma->obj))
 			i915_vma_unpin(vma);
 }
 
@@ -94,8 +94,8 @@ static void cleanup_objects(struct i915_ggtt *ggtt, struct list_head *list)
 	struct drm_i915_gem_object *obj, *on;
 
 	list_for_each_entry_safe(obj, on, list, st_link) {
-		GEM_BUG_ON(!obj->mm.quirked);
-		obj->mm.quirked = false;
+		GEM_BUG_ON(!i915_gem_object_has_tiling_quirk(obj));
+		i915_gem_object_set_tiling_quirk(obj);
 		i915_gem_object_put(obj);
 	}