[PATCH 16/26] block: move the io_stat flag setting to queue_limits

[Christoph Hellwig]

On Tue, Jun 11, 2024 at 05:09:45PM +0900, Damien Le Moal wrote:
> On 6/11/24 2:19 PM, Christoph Hellwig wrote:
> > Move the io_stat flag into the queue_limits feature field so that it
> > can be set atomically and all I/O is frozen when changing the flag.
> 
> Why a feature ? It seems more appropriate for io_stat to be a flag rather than
> a feature as that is a block layer thing rather than a device characteristic, no ?

Because it must actually be supported by the driver for bio based
drivers.  Then again we also support chaning it through sysfs, so
we might actually need both.  At least unlike say the cache it's
not actively harmful when enabled despite not being supported.

I can look into that, but I'll do it in another series after getting
all the driver changes out.