drm/amdgpu: stop using BO status for user pages

Instead use a counter to figure out if we need to set new pages or not.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -1802,6 +1802,7 @@ bool amdgpu_ttm_tt_affect_userptr(struct ttm_tt *ttm, unsigned long start,
 				  unsigned long end);
 bool amdgpu_ttm_tt_userptr_invalidated(struct ttm_tt *ttm,
 				       int *last_invalidated);
+bool amdgpu_ttm_tt_userptr_needs_pages(struct ttm_tt *ttm);
 bool amdgpu_ttm_tt_is_readonly(struct ttm_tt *ttm);
 uint64_t amdgpu_ttm_tt_pte_flags(struct amdgpu_device *adev, struct ttm_tt *ttm,
 				 struct ttm_mem_reg *mem);

drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c

@@ -473,7 +473,8 @@ static int amdgpu_cs_list_validate(struct amdgpu_cs_parser *p,
 			return -EPERM;
 
 		/* Check if we have user pages and nobody bound the BO already */
-		if (lobj->user_pages && bo->tbo.ttm->state != tt_bound) {
+		if (amdgpu_ttm_tt_userptr_needs_pages(bo->tbo.ttm) &&
+		    lobj->user_pages) {
 			amdgpu_ttm_tt_set_user_pages(bo->tbo.ttm,
 						     lobj->user_pages);
 			binding_userptr = true;
@@ -534,23 +535,25 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 		INIT_LIST_HEAD(&need_pages);
 		for (i = p->bo_list->first_userptr;
 		     i < p->bo_list->num_entries; ++i) {
+			struct amdgpu_bo *bo;
 
 			e = &p->bo_list->array[i];
+			bo = e->robj;
 
-			if (amdgpu_ttm_tt_userptr_invalidated(e->robj->tbo.ttm,
+			if (amdgpu_ttm_tt_userptr_invalidated(bo->tbo.ttm,
 				 &e->user_invalidated) && e->user_pages) {
 
 				/* We acquired a page array, but somebody
 				 * invalidated it. Free it and try again
 				 */
 				release_pages(e->user_pages,
-					      e->robj->tbo.ttm->num_pages,
+					      bo->tbo.ttm->num_pages,
 					      false);
 				kvfree(e->user_pages);
 				e->user_pages = NULL;
 			}
 
-			if (e->robj->tbo.ttm->state != tt_bound &&
+			if (amdgpu_ttm_tt_userptr_needs_pages(bo->tbo.ttm) &&
 			    !e->user_pages) {
 				list_del(&e->tv.head);
 				list_add(&e->tv.head, &need_pages);

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

@@ -609,6 +609,7 @@ struct amdgpu_ttm_tt {
 	spinlock_t              guptasklock;
 	struct list_head        guptasks;
 	atomic_t		mmu_invalidations;
+	uint32_t		last_set_pages;
 	struct list_head        list;
 };
 
@@ -672,8 +673,10 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages)
 
 void amdgpu_ttm_tt_set_user_pages(struct ttm_tt *ttm, struct page **pages)
 {
+	struct amdgpu_ttm_tt *gtt = (void *)ttm;
 	unsigned i;
 
+	gtt->last_set_pages = atomic_read(&gtt->mmu_invalidations);
 	for (i = 0; i < ttm->num_pages; ++i) {
 		if (ttm->pages[i])
 			put_page(ttm->pages[i]);
@@ -1025,6 +1028,7 @@ int amdgpu_ttm_tt_set_userptr(struct ttm_tt *ttm, uint64_t addr,
 	spin_lock_init(&gtt->guptasklock);
 	INIT_LIST_HEAD(&gtt->guptasks);
 	atomic_set(&gtt->mmu_invalidations, 0);
+	gtt->last_set_pages = 0;
 
 	return 0;
 }
@@ -1077,6 +1081,16 @@ bool amdgpu_ttm_tt_userptr_invalidated(struct ttm_tt *ttm,
 	return prev_invalidated != *last_invalidated;
 }
 
+bool amdgpu_ttm_tt_userptr_needs_pages(struct ttm_tt *ttm)
+{
+	struct amdgpu_ttm_tt *gtt = (void *)ttm;
+
+	if (gtt == NULL || !gtt->userptr)
+		return false;
+
+	return atomic_read(&gtt->mmu_invalidations) != gtt->last_set_pages;
+}
+
 bool amdgpu_ttm_tt_is_readonly(struct ttm_tt *ttm)
 {
 	struct amdgpu_ttm_tt *gtt = (void *)ttm;