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References: <20210311233142.7900-1-logang@deltatee.com>
 <20210311233142.7900-10-logang@deltatee.com> <20210316080051.GD15949@lst.de>
From:   Logan Gunthorpe <logang@deltatee.com>
Message-ID: <52a9e6e3-fc00-495a-69bb-26ff0b22775a@deltatee.com>
Date:   Tue, 16 Mar 2021 10:02:33 -0600
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Subject: Re: [RFC PATCH v2 09/11] block: Add BLK_STS_P2PDMA
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On 2021-03-16 2:00 a.m., Christoph Hellwig wrote:
> On Thu, Mar 11, 2021 at 04:31:39PM -0700, Logan Gunthorpe wrote:
>> Create a specific error code for when P2PDMA pages are passed to a block
>> devices that cannot map them (due to no IOMMU support or ACS protections).
>>
>> This makes request errors in these cases more informative of as to what
>> caused the error.
> 
> I really don't think we should bother with a specific error code here,
> we don't add a new status for every single possible logic error in the
> caller.

I originally had BLK_STS_IOERR but those errors suggested to people that
the hardware had failed on the request when in fact it was a user error.
I'll try BLK_STS_TARGET unless there's any objection or someone thinks
another error code would make more sense.

Logan