drm/nouveau: queue delayed unmapping of VMAs on client workqueue

VMAs are about to not take references on the VMM they belong to, which
means more care is required when handling delayed unmapping.

Queuing it on the client workqueue ensures all pending VMA unmaps will
have completed before the VMM is destroyed.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c
index a600c4386c72b7048aa2e96e01c6fb0a2563f1d9..2cf94e0591702bb175dea316f66a244151de9bd5 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -90,19 +90,33 @@ out:
        return ret;
 }
 
+struct nouveau_gem_object_unmap {
+       struct nouveau_cli_work work;
+       struct nouveau_vma *vma;
+};
+
 static void
-nouveau_gem_object_delete(void *data)
+nouveau_gem_object_delete(struct nouveau_vma *vma)
 {
-       struct nouveau_vma *vma = data;
        nouveau_vma_del(&vma);
 }
 
+static void
+nouveau_gem_object_delete_work(struct nouveau_cli_work *w)
+{
+       struct nouveau_gem_object_unmap *work =
+               container_of(w, typeof(*work), work);
+       nouveau_gem_object_delete(work->vma);
+       kfree(work);
+}
+
 static void
 nouveau_gem_object_unmap(struct nouveau_bo *nvbo, struct nouveau_vma *vma)
 {
        const bool mapped = nvbo->bo.mem.mem_type != TTM_PL_SYSTEM;
        struct reservation_object *resv = nvbo->bo.resv;
        struct reservation_object_list *fobj;
+       struct nouveau_gem_object_unmap *work;
        struct dma_fence *fence = NULL;
 
        fobj = reservation_object_get_list(resv);
@@ -117,10 +131,20 @@ nouveau_gem_object_unmap(struct nouveau_bo *nvbo, struct nouveau_vma *vma)
        else
                fence = reservation_object_get_excl(nvbo->bo.resv);
 
-       if (fence && mapped)
-               nouveau_fence_work(fence, nouveau_gem_object_delete, vma);
-       else
-               nouveau_vma_del(&vma);
+       if (!fence || !mapped) {
+               nouveau_gem_object_delete(vma);
+               return;
+       }
+
+       if (!(work = kmalloc(sizeof(*work), GFP_KERNEL))) {
+               WARN_ON(dma_fence_wait_timeout(fence, false, 2 * HZ) <= 0);
+               nouveau_gem_object_delete(vma);
+               return;
+       }
+
+       work->work.func = nouveau_gem_object_delete_work;
+       work->vma = vma;
+       nouveau_cli_work_queue(vma->vmm->cli, fence, &work->work);
 }
 
 void