From: Leon Romanovsky leonro@nvidia.com
IOMMUFD does not support page fault handling, and after a call to .invalidate_mappings() all mappings become invalid. Ensure that the IOMMUFD dma-buf importer is bound to a revoke‑aware dma-buf exporter (for example, VFIO).
Signed-off-by: Leon Romanovsky leonro@nvidia.com --- drivers/iommu/iommufd/pages.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/iommufd/pages.c b/drivers/iommu/iommufd/pages.c index 76f900fa1687..a5eb2bc4ef48 100644 --- a/drivers/iommu/iommufd/pages.c +++ b/drivers/iommu/iommufd/pages.c @@ -1501,16 +1501,22 @@ static int iopt_map_dmabuf(struct iommufd_ctx *ictx, struct iopt_pages *pages, mutex_unlock(&pages->mutex); }
- rc = sym_vfio_pci_dma_buf_iommufd_map(attach, &pages->dmabuf.phys); + rc = dma_buf_pin(attach); if (rc) goto err_detach;
+ rc = sym_vfio_pci_dma_buf_iommufd_map(attach, &pages->dmabuf.phys); + if (rc) + goto err_unpin; + dma_resv_unlock(dmabuf->resv);
/* On success iopt_release_pages() will detach and put the dmabuf. */ pages->dmabuf.attach = attach; return 0;
+err_unpin: + dma_buf_unpin(attach); err_detach: dma_resv_unlock(dmabuf->resv); dma_buf_detach(dmabuf, attach); @@ -1656,6 +1662,7 @@ void iopt_release_pages(struct kref *kref) if (iopt_is_dmabuf(pages) && pages->dmabuf.attach) { struct dma_buf *dmabuf = pages->dmabuf.attach->dmabuf;
+ dma_buf_unpin(pages->dmabuf.attach); dma_buf_detach(dmabuf, pages->dmabuf.attach); dma_buf_put(dmabuf); WARN_ON(!list_empty(&pages->dmabuf.tracker));