Re: [PATCH 1/2] PCI/P2PDMA: Update DMABUF lifecycle docs after move_notify() rename

[Leon Romanovsky]

On Thu, Sep 03, 2026 at 03:34:31PM -0500, Bjorn Helgaas wrote:
> On Tue, Aug 25, 2026 at 09:28:01AM +0300, Leon Romanovsky wrote:
> > From: Leon Romanovsky <leonro@xxxxxxxxxx>
> > 
> > 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()")
> > Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
> 
> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> 
> It looks like 2/2 might be updated, and it probably makes sense to
> merge them both together, but let me know if you want me to take this.

This PCI patch is completely standalone, so I sent it separately:
https://lore.kernel.org/all/20260830-doc-p2p-move-v1-1-61a388620588@xxxxxxxxxx/

Can you please take it from there?

Thanks

> 
> > ---
> >  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.
> > 
> > -- 
> > 2.55.0
> >