From 6ffe939bf94fbbeaaa4050a0e9c22820e959b15f Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Sat, 31 Jan 2026 07:34:17 +0200 Subject: [PATCH] vfio: Permit VFIO to work with pinned importers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Till now VFIO has rejected pinned importers, largely to avoid being used with the RDMA pinned importer that cannot handle a move_notify() to revoke access. Using dma_buf_attach_revocable() it can tell the difference between pinned importers that support the flow described in dma_buf_invalidate_mappings() and those that don't. Thus permit compatible pinned importers. This is one of two items IOMMUFD requires to remove its private interface to VFIO's dma-buf. Reviewed-by: Kevin Tian Reviewed-by: Alex Williamson Reviewed-by: Christian König Signed-off-by: Leon Romanovsky Signed-off-by: Christian König Link: https://lore.kernel.org/r/20260131-dmabuf-revoke-v7-7-463d956bd527@nvidia.com --- drivers/vfio/pci/vfio_pci_dmabuf.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci_dmabuf.c b/drivers/vfio/pci/vfio_pci_dmabuf.c index d7712d68ff2b..3a803923141b 100644 --- a/drivers/vfio/pci/vfio_pci_dmabuf.c +++ b/drivers/vfio/pci/vfio_pci_dmabuf.c @@ -22,16 +22,6 @@ struct vfio_pci_dma_buf { u8 revoked : 1; }; -static int vfio_pci_dma_buf_pin(struct dma_buf_attachment *attachment) -{ - return -EOPNOTSUPP; -} - -static void vfio_pci_dma_buf_unpin(struct dma_buf_attachment *attachment) -{ - /* Do nothing */ -} - static int vfio_pci_dma_buf_attach(struct dma_buf *dmabuf, struct dma_buf_attachment *attachment) { @@ -43,6 +33,9 @@ static int vfio_pci_dma_buf_attach(struct dma_buf *dmabuf, if (priv->revoked) return -ENODEV; + if (!dma_buf_attach_revocable(attachment)) + return -EOPNOTSUPP; + return 0; } @@ -107,8 +100,6 @@ static void vfio_pci_dma_buf_release(struct dma_buf *dmabuf) } static const struct dma_buf_ops vfio_pci_dmabuf_ops = { - .pin = vfio_pci_dma_buf_pin, - .unpin = vfio_pci_dma_buf_unpin, .attach = vfio_pci_dma_buf_attach, .map_dma_buf = vfio_pci_dma_buf_map, .unmap_dma_buf = vfio_pci_dma_buf_unmap,