[RFC PATCH v2 09/11] block: Add BLK_STS_P2PDMA

[Logan Gunthorpe]

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