Re: Bcache upstreaming

[Mike Snitzer <snitzer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On Thu, Jan 31 2013 at  5:25pm -0500,
Kent Overstreet <kent.overstreet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:

> On Thu, Jan 31, 2013 at 2:17 PM, Mike Snitzer <snitzer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
> > Ah, yeah I had a typo in my script.  When I fixed it I get a BUG (with
> > your latest bcache code) when I try to mkfs.xfs /dev/bcache0:
> 
> Heh, that's the dev branch - you don't want to be running the dev
> branch, there's a lot of buggy crap in there and it almost definitely
> corrupts data. Testing branch should be good, though.

OK, I'll pick up changes from -testing until directed elsewhere.

BTW, here are couple things I've noticed with bcache:

- The log messages seem to have an extra newline at the end.

- bcache doesn't appear to be establishing proper holders on the devices
  it uses for the backing and cache devices.
  - lsblk doesn't show any associations with bcache devices.
  - the fio utility isn't able to get any stats for the bcache device or
    the devices bcache uses.

- if I 'stop' a bcache device (using sysfs) while it is mounted; once I
  unmount the filesystem the device that bcache was using as a cache
  still has an open count of 1 but the bcache device then no longer
  exists