Re: [PATCH v6 03/18] PCI/P2PDMA: Derive routing from directional ACS controls

[Logan Gunthorpe]

On 2026-09-14 05:22, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@xxxxxxxxxx>
> 
> pci_bridge_has_acs_redir() treats Request and Completion Redirect as
> interchangeable. On asymmetric fabrics, a control for only the reverse TLP
> direction can unnecessarily force P2PDMA through the host bridge.
> 
> Evaluate Request Redirect for client Requests and Completion Redirect for
> provider read Completions. Continue treating enabled Egress Control
> conservatively as a Request redirect.
> 
> Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory")
> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>

Core patch seems fine, minus one minor point below:

Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>

> @@ -1132,10 +1173,10 @@ EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
>  /**
>   * pci_p2pdma_map_type - Determine the mapping type for P2PDMA transfers
>   * @provider: P2PDMA provider structure
> - * @dev: Target device for the transfer
> + * @dev: Client device that initiates the transfer
>   *
>   * Determines how peer-to-peer DMA transfers should be mapped between
> - * the provider and the target device. The mapping type indicates whether
> + * the provider and the client device. The mapping type indicates whether
>   * the transfer can be done directly through PCI switches or must go
>   * through the host bridge.
>   */
> 

This hunk does not seem like it belongs in this patch.