From: Leon Romanovsky leonro@nvidia.com
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.
Signed-off-by: Leon Romanovsky leonro@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 485515629fe4..3c8dc56e2238 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,