Re: [PATCH 04/15] dm: fix REQ_RAHEAD handling

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 resource=

s.

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.
=20
So remove this special casing and ignore all additional error handling fo=

r

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 <redacted>=