linux-kernel - Re: [RFC PATCH] dma: Add barrierless dma mapping/unmapping api

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] [day] [month] [year] [list]

Date:	Wed, 27 Jan 2010 17:49:47 +1100
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	FUJITA Tomonori <fujita.tomonori@....ntt.co.jp>
Cc:	adharmap@...eaurora.org, linux-kernel@...r.kernel.org,
	linux-arm-msm@...r.kernel.org, dwalker@...eaurora.org,
	arnd@...db.de, akpm@...ux-foundation.org, mingo@...e.hu,
	joerg.roedel@....com, maciej.sosnowski@...el.com,
	dan.j.williams@...el.com, beckyb@...nel.crashing.org,
	yanghy@...fujitsu.com, linux-arch@...r.kernel.org,
	adharmap@...cinc.com
Subject: Re: [RFC PATCH] dma: Add barrierless dma mapping/unmapping api

On Wed, 2010-01-27 at 14:19 +0900, FUJITA Tomonori wrote:
> > I somehow missed your post, my apologies. Agreed that
> dma_map/unmap_sg 
> > would be the correct api to use here, however they still call the 
> > dmac_.*_range to map buffers.
> 
> Hmm, sounds like arm's implementation issue. dma_map_sg API doesn't
> require such. dma_map_sg API gives what you want, do a sync only after
> mapping the last buffer.

dmac_* appears to be ARM's low-level ops for cache flushing on
non-coherent DMA, so it's really down to arch stuff here and how ARM
implements dma_[un]map_sg() and we keep a sane global driver API.

Cheers,
Ben.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/