Message-ID: <49CB387A.3000006@panasas.com>
Date: Thu, 26 Mar 2009 10:10:34 +0200
From: Boaz Harrosh <bharrosh@panasas.com>
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To: Tejun Heo <htejun@gmail.com>
CC: bzolnier@gmail.com, linux-kernel@vger.kernel.org, axboe@kernel.dk,
       linux-ide@vger.kernel.org
Subject: Re: [PATCH 03/14] block: implement blk_rq_map_kern_prealloc()
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On 03/26/2009 10:05 AM, Boaz Harrosh wrote:
> On 03/26/2009 09:42 AM, Tejun Heo wrote:
>> The thing is that the prealloc variant should be allowed to be called
>> from IRQ context and blk_queue_bounce() shouldn't be called.
>> Hmmm... well, the caller is supposed to know what it's doing and maybe
>> we can just add a comment that it shouldn't be called with buffers
>> which might get bounced from IRQ context.
>>
> 
> Hmm that is a problem. I would suggest a flag or a check. My bios come
> from VFS they need bouncing.
> 
> Can you think of a solution?
> 
> We could just call blk_queue_bounce(). IRQ callers need to make sure their
> buffers don't need bouncing anyway, so there is no such bug right? If a programmer
> gets it wrong he will get a BUG check that tells him that.
> 

I just realized that in your original call you had the "force" flag, we can keep
that flag for the blk_rq_set_bio(), or what ever we should name it.

Thanks
Boaz
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