Re: [PATCH v3 02/18] block: introduce BLK_STS_DURATION_LIMIT

Keith Busch
2023-01-24T20:00:03Z

On Tue, Jan 24, 2023 at 11:29:10AM -0800, Bart Van Assche wrote:
> On 1/24/23 11:02, Niklas Cassel wrote:
> > Introduce the new block IO status BLK_STS_DURATION_LIMIT for LLDDs to
> > report command that failed due to a command duration limit being
> > exceeded. This new status is mapped to the ETIME error code to allow
> > users to differentiate "soft" duration limit failures from other more
> > serious hardware related errors.
>
> What makes exceeding the duration limit different from an I/O timeout
> (BLK_STS_TIMEOUT)? Why is it important to tell the difference between an I/O
> timeout and exceeding the command duration limit?

BLK_STS_TIMEOUT should be used if the target device doesn't provide any
response to the command. The DURATION_LIMIT status is used when the device
completes a command with that status.