linux-kernel - Re: [PATCHv3] DMAEngine: Define interleaved transfer request 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] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 21 Sep 2011 12:15:42 +0530
From:	Jassi Brar <jaswinder.singh@...aro.org>
To:	Vinod Koul <vinod.koul@...el.com>
Cc:	dan.j.williams@...el.com, linux-kernel@...r.kernel.org,
	rmk@....linux.org.uk, 21cnbao@...il.com
Subject: Re: [PATCHv3] DMAEngine: Define interleaved transfer request api

On 21 September 2011 12:02, Vinod Koul <vinod.koul@...el.com> wrote:
> On Tue, 2011-09-20 at 23:38 +0530, Jassi Brar wrote:
>> On 20 September 2011 22:22, Vinod Koul <vinod.koul@...el.com> wrote:
>> > Also for slave transfers, how do we infer direction?
>> I already explained to Barry.  Here's it again.
>>
>> At any time, the dmac driver knows if the channel, on which the xfer is
>> prepared/submitted is Slave or not.
>>
>> SLAVE Transfer
>>    dmaxfer_template.src_inc  && !dmaxfer_template.dst_inc  => DMA_TO_DEVICE
>>    !dmaxfer_template.src_inc  && dmaxfer_template.dst_inc  => DMA_FROM_DEVICE
>>
>> Mem->Mem Transfer
>>    dmaxfer_template.src_inc  && !dmaxfer_template.dst_inc  => Meaningless
>>    !dmaxfer_template.src_inc  && dmaxfer_template.dst_inc  => MemSet
> Rather than each driver adding this logic with good chance of screwing
> up, care to add this as helper in dmaengine.h
>
> Ideally, I would have preferred direction to be told explicitly, would
> leave it you..
>
I repeat yet again :- "This api is common to Slave as well as Mem<->Mem"

Even if we have slave clients specify DMA_TO/FROM_DEVICE, what
flag do you suggest Mem->Mem clients use ?
--
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/