[dm-devel] [PATCH 04/15] dm: fix REQ_RAHEAD handling

[Bart Van Assche]

On Thu, 2017-05-18 at 15:18 +0200, Christoph Hellwig wrote:
> A few (but not all) dm targets use a special EWOULDBLOCK error code for
> failing REQ_RAHEAD requests that fail due to a lack of available resources.
> But no one else knows about this magic code, and lower level drivers also
> don't generate it when failing read-ahead requests for similar reasons.
> 
> So remove this special casing and ignore all additional error handling for
> REQ_RAHEAD - if this was a real underlying error we'd get a normal read
> once the real read comes in.

Reviewed-by: Bart Van Assche <Bart.VanAssche at sandisk.com>