drm/amdgpu: fix userq VM validation v4

That was actually complete nonsense and not validating the BOs
at all. The code just cleared all VM areas were it couldn't grab the
lock for a BO.

Try to fix this. Only compile tested at the moment.

v2: fix fence slot reservation as well as pointed out by Sunil.
    also validate PDs, PTs, per VM BOs and update PDEs
v3: grab the status_lock while working with the done list.
v4: rename functions, add some comments, fix waiting for updates to
    complete.
v4: rename amdgpu_vm_lock_done_list(), add some more comments

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Sunil Khatri <sunil.khatri@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index bd12d8ff15a4..9980c0cded94 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -485,6 +485,41 @@ int amdgpu_vm_lock_pd(struct amdgpu_vm *vm, struct drm_exec *exec,
 }
 
 /**
+ * amdgpu_vm_lock_done_list - lock all BOs on the done list
+ * @exec: drm execution context
+ * @num_fences: number of extra fences to reserve
+ *
+ * Lock the BOs on the done list in the DRM execution context.
+ */
+int amdgpu_vm_lock_done_list(struct amdgpu_vm *vm, struct drm_exec *exec,
+			     unsigned int num_fences)
+{
+	struct list_head *prev = &vm->done;
+	struct amdgpu_bo_va *bo_va;
+	struct amdgpu_bo *bo;
+	int ret;
+
+	/* We can only trust prev->next while holding the lock */
+	spin_lock(&vm->status_lock);
+	while (!list_is_head(prev->next, &vm->done)) {
+		bo_va = list_entry(prev->next, typeof(*bo_va), base.vm_status);
+		spin_unlock(&vm->status_lock);
+
+		bo = bo_va->base.bo;
+		if (bo) {
+			ret = drm_exec_prepare_obj(exec, &bo->tbo.base, 1);
+			if (unlikely(ret))
+				return ret;
+		}
+		spin_lock(&vm->status_lock);
+		prev = prev->next;
+	}
+	spin_unlock(&vm->status_lock);
+
+	return 0;
+}
+
+/**
  * amdgpu_vm_move_to_lru_tail - move all BOs to the end of LRU
  *
  * @adev: amdgpu device pointer