linux-kernel - Re: [PATCH v4 11/16] dma-mapping: export new dma_*map

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aKTA5i1IZquRBolf@kbusch-mbp>
Date: Tue, 19 Aug 2025 12:22:30 -0600
From: Keith Busch <kbusch@...nel.org>
To: Leon Romanovsky <leon@...nel.org>
Cc: Marek Szyprowski <m.szyprowski@...sung.com>,
	Leon Romanovsky <leonro@...dia.com>,
	Jason Gunthorpe <jgg@...dia.com>,
	Abdiel Janulgue <abdiel.janulgue@...il.com>,
	Alexander Potapenko <glider@...gle.com>,
	Alex Gaynor <alex.gaynor@...il.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Christoph Hellwig <hch@....de>, Danilo Krummrich <dakr@...nel.org>,
	iommu@...ts.linux.dev, Jason Wang <jasowang@...hat.com>,
	Jens Axboe <axboe@...nel.dk>, Joerg Roedel <joro@...tes.org>,
	Jonathan Corbet <corbet@....net>, Juergen Gross <jgross@...e.com>,
	kasan-dev@...glegroups.com, linux-block@...r.kernel.org,
	linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, linux-nvme@...ts.infradead.org,
	linuxppc-dev@...ts.ozlabs.org, linux-trace-kernel@...r.kernel.org,
	Madhavan Srinivasan <maddy@...ux.ibm.com>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	Michael Ellerman <mpe@...erman.id.au>,
	"Michael S. Tsirkin" <mst@...hat.com>,
	Miguel Ojeda <ojeda@...nel.org>,
	Robin Murphy <robin.murphy@....com>, rust-for-linux@...r.kernel.org,
	Sagi Grimberg <sagi@...mberg.me>,
	Stefano Stabellini <sstabellini@...nel.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	virtualization@...ts.linux.dev, Will Deacon <will@...nel.org>,
	xen-devel@...ts.xenproject.org
Subject: Re: [PATCH v4 11/16] dma-mapping: export new dma_*map_phys()
 interface

On Tue, Aug 19, 2025 at 08:36:55PM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@...dia.com>
> 
> Introduce new DMA mapping functions dma_map_phys() and dma_unmap_phys()
> that operate directly on physical addresses instead of page+offset
> parameters. This provides a more efficient interface for drivers that
> already have physical addresses available.
> 
> The new functions are implemented as the primary mapping layer, with
> the existing dma_map_page_attrs()/dma_map_resource() and
> dma_unmap_page_attrs()/dma_unmap_resource() functions converted to simple
> wrappers around the phys-based implementations.
> 
> In case dma_map_page_attrs(), the struct page is converted to physical
> address with help of page_to_phys() function and dma_map_resource()
> provides physical address as is together with addition of DMA_ATTR_MMIO
> attribute.
> 
> The old page-based API is preserved in mapping.c to ensure that existing
> code won't be affected by changing EXPORT_SYMBOL to EXPORT_SYMBOL_GPL
> variant for dma_*map_phys().

Looks good.

Reviewed-by: Keith Busch <kbusch@...nel.org>