On Tue, Apr 07, 2015 at 10:13:23AM -0600, Jens Axboe wrote:
The mq case will also work for the !mq case when you call
scsi_host_find_tag and scsi_cmd_priv. In general all the mq-specific
codepathes you add should become the default and only one, even if this
requires a lit bit of additional core work.
For the core code, I definitely agree. But for this case, in scsi-mq mode,
we know that tag == smid - 1. That's not the case if we are not using
It is if you use the old block tagging code with host-wide tags.
I guess you'll need to tell mpt2 and mpt3 to use that firs, though.
In general, it'd be great if we could "convert" drivers and not have to
support both scsi-mq and legacy mode. Then I could just rip the old code.
Well, the whole point is that you should be able to write a driver like
your mq version and it should just work. Even better would be if we
could get rid of the old case entirely for scsi, but for that we need
a I/O scheduler for blk-mq first :)