On Thu, Nov 05, 2020 at 08:42:03AM +0100, Christoph Hellwig wrote:
> Now that all users of dma_virt_ops are gone we can remove the workaround
> for it in the PCI peer to peer code.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> drivers/pci/p2pdma.c | 20 --------------------
> 1 file changed, 20 deletions(-)
>
> diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
> index de1c331dbed43f..b07018af53876c 100644
> +++ b/drivers/pci/p2pdma.c
> @@ -556,15 +556,6 @@ int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
> return -1;
>
> for (i = 0; i < num_clients; i++) {
> -#ifdef CONFIG_DMA_VIRT_OPS
> - if (clients[i]->dma_ops == &dma_virt_ops) {
> - if (verbose)
> - dev_warn(clients[i],
> - "cannot be used for peer-to-peer DMA because the driver makes use of dma_virt_ops\n");
> - return -1;
> - }
> -#endif
> -
> pci_client = find_parent_pci_dev(clients[i]);
> if (!pci_client) {
> if (verbose)
> @@ -837,17 +828,6 @@ static int __pci_p2pdma_map_sg(struct pci_p2pdma_pagemap *p2p_pgmap,
> phys_addr_t paddr;
> int i;
>
> - /*
> - * p2pdma mappings are not compatible with devices that use
> - * dma_virt_ops. If the upper layers do the right thing
> - * this should never happen because it will be prevented
> - * by the check in pci_p2pdma_distance_many()
> - */
> -#ifdef CONFIG_DMA_VIRT_OPS
> - if (WARN_ON_ONCE(dev->dma_ops == &dma_virt_ops))
> - return 0;
> -#endif
The check is removed here, but I didn't see a matching check added to
the IB side? Something like:
static int rdma_rw_map_sg(struct ib_device *dev, struct scatterlist *sg,
u32 sg_cnt, enum dma_data_direction dir)
{
if (is_pci_p2pdma_page(sg_page(sg))) {
if (ib_uses_virt_dma(dev))
return 0;
return pci_p2pdma_map_sg(dev->dma_device, sg, sg_cnt, dir);
}
return ib_dma_map_sg(dev, sg, sg_cnt, dir);
}
I think the change to rdma_rw_unmap_sg() should probably be dropped in
favour of the above?
Jason
