drm/amdgpu: fix the broken vm->mutex V2

fix the vm->mutex and ww_mutex confilcts.
vm->mutex is always token first, then ww_mutex.

V2: remove unneccessary checking for pt bo.

Change-Id: Iea56e183752c02831126d06d2f5b7a474a6e4743
Signed-off-by: Chunming Zhou <david1.zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 5fdc039..8727c30 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -608,7 +608,6 @@
 		}
 	}
 
-	mutex_lock(&vm->mutex);
 	r = amdgpu_bo_vm_update_pte(parser, vm);
 	if (r) {
 		goto out;
@@ -619,7 +618,6 @@
 				       parser->filp);
 
 out:
-	mutex_unlock(&vm->mutex);
 	return r;
 }
 
@@ -827,6 +825,8 @@
 {
 	struct amdgpu_device *adev = dev->dev_private;
 	union drm_amdgpu_cs *cs = data;
+	struct amdgpu_fpriv *fpriv = filp->driver_priv;
+	struct amdgpu_vm *vm = &fpriv->vm;
 	struct amdgpu_cs_parser *parser;
 	bool reserved_buffers = false;
 	int i, r;
@@ -844,7 +844,7 @@
 		r = amdgpu_cs_handle_lockup(adev, r);
 		return r;
 	}
-
+	mutex_lock(&vm->mutex);
 	r = amdgpu_cs_parser_relocs(parser);
 	if (r == -ENOMEM)
 		DRM_ERROR("Not enough memory for command submission!\n");
@@ -911,12 +911,14 @@
 
 		mutex_unlock(&job->job_lock);
 		amdgpu_cs_parser_fini_late(parser);
+		mutex_unlock(&vm->mutex);
 		return 0;
 	}
 
 	cs->out.handle = parser->ibs[parser->num_ibs - 1].sequence;
 out:
 	amdgpu_cs_parser_fini(parser, r, reserved_buffers);
+	mutex_unlock(&vm->mutex);
 	r = amdgpu_cs_handle_lockup(adev, r);
 	return r;
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index d81ab78..0873328 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -115,9 +115,10 @@
 	struct amdgpu_vm *vm = &fpriv->vm;
 	struct amdgpu_bo_va *bo_va;
 	int r;
-
+	mutex_lock(&vm->mutex);
 	r = amdgpu_bo_reserve(rbo, false);
 	if (r) {
+		mutex_unlock(&vm->mutex);
 		return r;
 	}
 
@@ -128,7 +129,7 @@
 		++bo_va->ref_count;
 	}
 	amdgpu_bo_unreserve(rbo);
-
+	mutex_unlock(&vm->mutex);
 	return 0;
 }
 
@@ -141,9 +142,10 @@
 	struct amdgpu_vm *vm = &fpriv->vm;
 	struct amdgpu_bo_va *bo_va;
 	int r;
-
+	mutex_lock(&vm->mutex);
 	r = amdgpu_bo_reserve(rbo, true);
 	if (r) {
+		mutex_unlock(&vm->mutex);
 		dev_err(adev->dev, "leaking bo va because "
 			"we fail to reserve bo (%d)\n", r);
 		return;
@@ -155,6 +157,7 @@
 		}
 	}
 	amdgpu_bo_unreserve(rbo);
+	mutex_unlock(&vm->mutex);
 }
 
 static int amdgpu_gem_handle_lockup(struct amdgpu_device *adev, int r)
@@ -481,18 +484,13 @@
 			goto error_unreserve;
 	}
 
-	mutex_lock(&bo_va->vm->mutex);
 	r = amdgpu_vm_clear_freed(adev, bo_va->vm);
 	if (r)
-		goto error_unlock;
-
+		goto error_unreserve;
 
 	if (operation == AMDGPU_VA_OP_MAP)
 		r = amdgpu_vm_bo_update(adev, bo_va, &bo_va->bo->tbo.mem);
 
-error_unlock:
-	mutex_unlock(&bo_va->vm->mutex);
-
 error_unreserve:
 	ttm_eu_backoff_reservation(&ticket, &list);
 
@@ -549,10 +547,11 @@
 	gobj = drm_gem_object_lookup(dev, filp, args->handle);
 	if (gobj == NULL)
 		return -ENOENT;
-
+	mutex_lock(&fpriv->vm.mutex);
 	rbo = gem_to_amdgpu_bo(gobj);
 	r = amdgpu_bo_reserve(rbo, false);
 	if (r) {
+		mutex_unlock(&fpriv->vm.mutex);
 		drm_gem_object_unreference_unlocked(gobj);
 		return r;
 	}
@@ -560,6 +559,7 @@
 	bo_va = amdgpu_vm_bo_find(&fpriv->vm, rbo);
 	if (!bo_va) {
 		amdgpu_bo_unreserve(rbo);
+		mutex_unlock(&fpriv->vm.mutex);
 		return -ENOENT;
 	}
 
@@ -584,7 +584,7 @@
 
 	if (!r && !(args->flags & AMDGPU_VM_DELAY_UPDATE))
 		amdgpu_gem_va_update_vm(adev, bo_va, args->operation);
-
+	mutex_unlock(&fpriv->vm.mutex);
 	drm_gem_object_unreference_unlocked(gobj);
 	return r;
 }
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 0675524..06e207f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -90,11 +90,9 @@
 	struct amdgpu_bo_list_entry *list;
 	unsigned i, idx;
 
-	mutex_lock(&vm->mutex);
 	list = drm_malloc_ab(vm->max_pde_used + 2,
 			     sizeof(struct amdgpu_bo_list_entry));
 	if (!list) {
-		mutex_unlock(&vm->mutex);
 		return NULL;
 	}
 
@@ -119,7 +117,6 @@
 		list[idx].tv.shared = true;
 		list_add(&list[idx++].tv.head, head);
 	}
-	mutex_unlock(&vm->mutex);
 
 	return list;
 }
@@ -970,9 +967,7 @@
 	INIT_LIST_HEAD(&bo_va->invalids);
 	INIT_LIST_HEAD(&bo_va->vm_status);
 
-	mutex_lock(&vm->mutex);
 	list_add_tail(&bo_va->bo_list, &bo->va);
-	mutex_unlock(&vm->mutex);
 
 	return bo_va;
 }
@@ -1025,8 +1020,6 @@
 		return -EINVAL;
 	}
 
-	mutex_lock(&vm->mutex);
-
 	saddr /= AMDGPU_GPU_PAGE_SIZE;
 	eaddr /= AMDGPU_GPU_PAGE_SIZE;
 
@@ -1040,14 +1033,14 @@
 			tmp->it.start, tmp->it.last + 1);
 		amdgpu_bo_unreserve(bo_va->bo);
 		r = -EINVAL;
-		goto error_unlock;
+		goto error;
 	}
 
 	mapping = kmalloc(sizeof(*mapping), GFP_KERNEL);
 	if (!mapping) {
 		amdgpu_bo_unreserve(bo_va->bo);
 		r = -ENOMEM;
-		goto error_unlock;
+		goto error;
 	}
 
 	INIT_LIST_HEAD(&mapping->list);
@@ -1079,9 +1072,6 @@
 		if (vm->page_tables[pt_idx].bo)
 			continue;
 
-		/* drop mutex to allocate and clear page table */
-		mutex_unlock(&vm->mutex);
-
 		ww_mutex_lock(&resv->lock, NULL);
 		r = amdgpu_bo_create(adev, AMDGPU_VM_PTE_COUNT * 8,
 				     AMDGPU_GPU_PAGE_SIZE, true,
@@ -1098,32 +1088,19 @@
 			goto error_free;
 		}
 
-		/* aquire mutex again */
-		mutex_lock(&vm->mutex);
-		if (vm->page_tables[pt_idx].bo) {
-			/* someone else allocated the pt in the meantime */
-			mutex_unlock(&vm->mutex);
-			amdgpu_bo_unref(&pt);
-			mutex_lock(&vm->mutex);
-			continue;
-		}
-
 		vm->page_tables[pt_idx].addr = 0;
 		vm->page_tables[pt_idx].bo = pt;
 	}
 
-	mutex_unlock(&vm->mutex);
 	return 0;
 
 error_free:
-	mutex_lock(&vm->mutex);
 	list_del(&mapping->list);
 	interval_tree_remove(&mapping->it, &vm->va);
 	trace_amdgpu_vm_bo_unmap(bo_va, mapping);
 	kfree(mapping);
 
-error_unlock:
-	mutex_unlock(&vm->mutex);
+error:
 	return r;
 }
 
@@ -1168,7 +1145,6 @@
 		}
 	}
 
-	mutex_lock(&vm->mutex);
 	list_del(&mapping->list);
 	interval_tree_remove(&mapping->it, &vm->va);
 	trace_amdgpu_vm_bo_unmap(bo_va, mapping);
@@ -1177,7 +1153,6 @@
 		list_add(&mapping->list, &vm->freed);
 	else
 		kfree(mapping);
-	mutex_unlock(&vm->mutex);
 	amdgpu_bo_unreserve(bo_va->bo);
 
 	return 0;
@@ -1201,8 +1176,6 @@
 
 	list_del(&bo_va->bo_list);
 
-	mutex_lock(&vm->mutex);
-
 	spin_lock(&vm->status_lock);
 	list_del(&bo_va->vm_status);
 	spin_unlock(&vm->status_lock);
@@ -1221,8 +1194,6 @@
 
 	fence_put(bo_va->last_pt_update);
 	kfree(bo_va);
-
-	mutex_unlock(&vm->mutex);
 }
 
 /**