Simple conversion to add a match_mapping() callback that offers an exporter SGT mapping type. Later patches will add a physical address exporter so go straight to adding the match_mapping() function.
The check for attachment->peer2peer is replaced with setting exporter_requires_p2p=true. VFIO always uses MMIO memory. Signed-off-by: Jason Gunthorpe <[email protected]> --- drivers/vfio/pci/vfio_pci_dmabuf.c | 31 +++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci_dmabuf.c b/drivers/vfio/pci/vfio_pci_dmabuf.c index d4d0f7d08c53e2..c7addef5794abf 100644 --- a/drivers/vfio/pci/vfio_pci_dmabuf.c +++ b/drivers/vfio/pci/vfio_pci_dmabuf.c @@ -25,9 +25,6 @@ static int vfio_pci_dma_buf_attach(struct dma_buf *dmabuf, { struct vfio_pci_dma_buf *priv = dmabuf->priv; - if (!attachment->peer2peer) - return -EOPNOTSUPP; - if (priv->revoked) return -ENODEV; @@ -75,11 +72,35 @@ static void vfio_pci_dma_buf_release(struct dma_buf *dmabuf) kfree(priv); } -static const struct dma_buf_ops vfio_pci_dmabuf_ops = { - .attach = vfio_pci_dma_buf_attach, +static const struct dma_buf_mapping_sgt_exp_ops vfio_pci_dma_buf_sgt_ops = { .map_dma_buf = vfio_pci_dma_buf_map, .unmap_dma_buf = vfio_pci_dma_buf_unmap, +}; + +static int vfio_pci_dma_buf_match_mapping(struct dma_buf_match_args *args) +{ + struct vfio_pci_dma_buf *priv = args->dmabuf->priv; + struct dma_buf_mapping_match sgt_match[1]; + + dma_resv_assert_held(priv->dmabuf->resv); + + /* + * Once we pass vfio_pci_dma_buf_cleanup() the dmabuf will never be + * usable again. + */ + if (!priv->vdev) + return -ENODEV; + + sgt_match[0] = DMA_BUF_EMAPPING_SGT_P2P(&vfio_pci_dma_buf_sgt_ops, + priv->vdev->pdev); + + return dma_buf_match_mapping(args, sgt_match, ARRAY_SIZE(sgt_match)); +} + +static const struct dma_buf_ops vfio_pci_dmabuf_ops = { + .attach = vfio_pci_dma_buf_attach, .release = vfio_pci_dma_buf_release, + .match_mapping = vfio_pci_dma_buf_match_mapping, }; /* -- 2.43.0
