Re: [PATCH] PCI/P2PDMA: Update DMABUF lifecycle docs after move_notify() rename

[Bjorn Helgaas <helgaas@kernel.org>]

On Sun, Aug 30, 2026 at 03:31:49PM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
> 
> Commit 95308225e5ba ("dma-buf: Rename dma_buf_move_notify() to
> dma_buf_invalidate_mappings()") left the DMABUF section of the P2PDMA
> documentation pointing at move_notify(), a symbol that no longer
> exists. Readers grepping for it find nothing, and this is the only
> place in Documentation/ describing the revocation requirement.
> 
> Name the current function and record that importers which cannot unmap
> within bounded time have to be rejected at attach time, which is what
> makes the synchronous unmap on remove() achievable.
> 
> Fixes: 95308225e5ba ("dma-buf: Rename dma_buf_move_notify() to dma_buf_invalidate_mappings()")
> Reviewed-by: Christian König <christian.koenig@amd.com>
> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Applied on pci/p2pdma for v7.4, thank you!

> ---
>  * Split from https://lore.kernel.org/all/20260825-document-dma-buf-v1-0-5ecfb3e1371c@nvidia.com
> ---
>  Documentation/driver-api/pci/p2pdma.rst | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/driver-api/pci/p2pdma.rst b/Documentation/driver-api/pci/p2pdma.rst
> index d3f406cca694..63cff9e4d2c9 100644
> --- a/Documentation/driver-api/pci/p2pdma.rst
> +++ b/Documentation/driver-api/pci/p2pdma.rst
> @@ -167,9 +167,11 @@ In this case the initiator and target pci_devices are known and the P2P subsyste
>  is used to determine the mapping type. The phys_addr_t-based DMA API is used to
>  establish the dma_addr_t.
>  
> -Lifecycle is controlled by DMABUF move_notify(). When the exporting driver wants
> +Lifecycle is controlled by DMABUF revocation. When the exporting driver wants
>  to remove() it must deliver an invalidation shutdown to all DMABUF importing
> -drivers through move_notify() and synchronously DMA unmap all the MMIO.
> +drivers through dma_buf_invalidate_mappings() and synchronously DMA unmap all
> +the MMIO. Importers unable to complete that unmap within bounded time have to
> +be rejected when they attach, which dma_buf_attach_revocable() checks for.
>  
>  No importing driver can continue to have a DMA map to the MMIO after the
>  exporting driver has destroyed its p2p_provider.
> 
> ---
> base-commit: 08dbfad3f5040f5bdb6c529da20d6d4e81fefd72
> change-id: 20260830-doc-p2p-move-05aad5de1ec1
> 
> Best regards,
> --  
> Leon Romanovsky <leonro@nvidia.com>
>