drm/radeon: fix VM IB handling

Calling radeon_vm_bo_find on the IB BO during CS
is illegal and can lead to an crash.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon.h

@@ -879,6 +879,8 @@ struct radeon_vm {
 	/* array of page tables, one for each page directory entry */
 	struct radeon_vm_pt		*page_tables;
 
+	struct radeon_bo_va		*ib_bo_va;
+
 	struct mutex			mutex;
 	/* last fence for cs using this vm */
 	struct radeon_fence		*fence;

drivers/gpu/drm/radeon/radeon_cs.c

@@ -472,13 +472,13 @@ static int radeon_bo_vm_update_pte(struct radeon_cs_parser *p,
 	if (r)
 		return r;
 
-	bo_va = radeon_vm_bo_find(vm, rdev->ring_tmp_bo.bo);
-	if (bo_va == NULL) {
+	if (vm->ib_bo_va == NULL) {
 		DRM_ERROR("Tmp BO not in VM!\n");
 		return -EINVAL;
 	}
 
-	r = radeon_vm_bo_update(rdev, bo_va, &rdev->ring_tmp_bo.bo->tbo.mem);
+	r = radeon_vm_bo_update(rdev, vm->ib_bo_va,
+				&rdev->ring_tmp_bo.bo->tbo.mem);
 	if (r)
 		return r;
 

drivers/gpu/drm/radeon/radeon_kms.c

@@ -579,7 +579,7 @@ int radeon_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv)
 	/* new gpu have virtual address space support */
 	if (rdev->family >= CHIP_CAYMAN) {
 		struct radeon_fpriv *fpriv;
-		struct radeon_bo_va *bo_va;
+		struct radeon_vm *vm;
 		int r;
 
 		fpriv = kzalloc(sizeof(*fpriv), GFP_KERNEL);
@@ -587,7 +587,8 @@ int radeon_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv)
 			return -ENOMEM;
 		}
 
-		r = radeon_vm_init(rdev, &fpriv->vm);
+		vm = &fpriv->vm;
+		r = radeon_vm_init(rdev, vm);
 		if (r) {
 			kfree(fpriv);
 			return r;
@@ -596,22 +597,23 @@ int radeon_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv)
 		if (rdev->accel_working) {
 			r = radeon_bo_reserve(rdev->ring_tmp_bo.bo, false);
 			if (r) {
-				radeon_vm_fini(rdev, &fpriv->vm);
+				radeon_vm_fini(rdev, vm);
 				kfree(fpriv);
 				return r;
 			}
 
 			/* map the ib pool buffer read only into
 			 * virtual address space */
-			bo_va = radeon_vm_bo_add(rdev, &fpriv->vm,
-						 rdev->ring_tmp_bo.bo);
-			r = radeon_vm_bo_set_addr(rdev, bo_va, RADEON_VA_IB_OFFSET,
+			vm->ib_bo_va = radeon_vm_bo_add(rdev, vm,
+							rdev->ring_tmp_bo.bo);
+			r = radeon_vm_bo_set_addr(rdev, vm->ib_bo_va,
+						  RADEON_VA_IB_OFFSET,
 						  RADEON_VM_PAGE_READABLE |
 						  RADEON_VM_PAGE_SNOOPED);
 
 			radeon_bo_unreserve(rdev->ring_tmp_bo.bo);
 			if (r) {
-				radeon_vm_fini(rdev, &fpriv->vm);
+				radeon_vm_fini(rdev, vm);
 				kfree(fpriv);
 				return r;
 			}
@@ -640,21 +642,19 @@ void radeon_driver_postclose_kms(struct drm_device *dev,
 	/* new gpu have virtual address space support */
 	if (rdev->family >= CHIP_CAYMAN && file_priv->driver_priv) {
 		struct radeon_fpriv *fpriv = file_priv->driver_priv;
-		struct radeon_bo_va *bo_va;
+		struct radeon_vm *vm = &fpriv->vm;
 		int r;
 
 		if (rdev->accel_working) {
 			r = radeon_bo_reserve(rdev->ring_tmp_bo.bo, false);
 			if (!r) {
-				bo_va = radeon_vm_bo_find(&fpriv->vm,
-							  rdev->ring_tmp_bo.bo);
-				if (bo_va)
-					radeon_vm_bo_rmv(rdev, bo_va);
+				if (vm->ib_bo_va)
+					radeon_vm_bo_rmv(rdev, vm->ib_bo_va);
 				radeon_bo_unreserve(rdev->ring_tmp_bo.bo);
 			}
 		}
 
-		radeon_vm_fini(rdev, &fpriv->vm);
+		radeon_vm_fini(rdev, vm);
 		kfree(fpriv);
 		file_priv->driver_priv = NULL;
 	}

drivers/gpu/drm/radeon/radeon_vm.c

@@ -1007,6 +1007,7 @@ int radeon_vm_init(struct radeon_device *rdev, struct radeon_vm *vm)
 	int r;
 
 	vm->id = 0;
+	vm->ib_bo_va = NULL;
 	vm->fence = NULL;
 	vm->last_flush = NULL;
 	vm->last_id_use = NULL;