Commit 575157b1 authored by Leon Romanovsky's avatar Leon Romanovsky Committed by Christian König
Browse files

dma-buf: Make .invalidate_mapping() truly optional 



The .invalidate_mapping() callback is documented as optional, yet it
effectively became mandatory whenever importer_ops were provided. This
led to cases where RDMA non-ODP code had to supply an empty stub.

Relax the checks in the dma-buf core so the callback can be omitted,
allowing RDMA code to drop the unnecessary function.

Removing the stub allows the next patch to tell that RDMA does not support
.invalidate_mapping() by checking for a NULL op.

Signed-off-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20260131-dmabuf-revoke-v7-5-463d956bd527@nvidia.com
parent 1a8a5227

drivers/dma-buf/dma-buf.c

+2 −4
Original line number Diff line number Diff line
@@ -1016,9 +1016,6 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, 
	if (WARN_ON(!dmabuf || !dev))

		return ERR_PTR(-EINVAL);



	if (WARN_ON(importer_ops && !importer_ops->invalidate_mappings))

		return ERR_PTR(-EINVAL);



	attach = kzalloc_obj(*attach);

	if (!attach)

		return ERR_PTR(-ENOMEM);
@@ -1336,7 +1333,8 @@ void dma_buf_invalidate_mappings(struct dma_buf *dmabuf) 
	dma_resv_assert_held(dmabuf->resv);



	list_for_each_entry(attach, &dmabuf->attachments, node)

		if (attach->importer_ops)

		if (attach->importer_ops &&

		    attach->importer_ops->invalidate_mappings)

			attach->importer_ops->invalidate_mappings(attach);

}

EXPORT_SYMBOL_NS_GPL(dma_buf_invalidate_mappings, "DMA_BUF");

drivers/infiniband/core/umem_dmabuf.c

+0 −10
Original line number Diff line number Diff line
@@ -181,18 +181,8 @@ struct ib_umem_dmabuf *ib_umem_dmabuf_get(struct ib_device *device, 
}

EXPORT_SYMBOL(ib_umem_dmabuf_get);



static void

ib_umem_dmabuf_unsupported_move_notify(struct dma_buf_attachment *attach)

{

	struct ib_umem_dmabuf *umem_dmabuf = attach->importer_priv;



	ibdev_warn_ratelimited(umem_dmabuf->umem.ibdev,

			       "Invalidate callback should not be called when memory is pinned\n");

}



static struct dma_buf_attach_ops ib_umem_dmabuf_attach_pinned_ops = {

	.allow_peer2peer = true,

	.invalidate_mappings = ib_umem_dmabuf_unsupported_move_notify,

};



struct ib_umem_dmabuf *