Re: [RFC PATCH 0/7] bcache: md conversion

[Joseph Glanville <joseph.glanville@xxxxxxxxxxxxxx>]

On 12 May 2012 05:46, Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
> The consensus from LSF was that bcache need not invent a new interface
> when md and dm can both do the job.  As mentioned in patch 7 this series
> aims to be a minimal conversion.  Other refactoring items like
> deprecating register_lock for mddev->reconfig_mutex are deferred.
>
> This supports assembly of an already established cache array:
>
>        mdadm -A /dev/md/bcache /dev/sd[ab]
>
> ...will create the /dev/md/bcache container and a subarray representing
> the cache volume.  "Flash-only", or backing-device only volumes were not
> tested.  "Create" support and hot-add/hot-remove come later.
>
> Note:
> * When attempting to test with small loopback devices (100MB), assembly
>  soft locks in bcache_journal_read().  That hang went away with larger
>  devices, so there seems to be minimum component device size that needs
>  to be considered in the tooling.
>
> ---
>
> Dan Williams (7):
>      bcache: compile fix
>      bcache: disable lockdep, enable CONFIG_BCACHE=m
>      bcache: drop select COMPACTION
>      bcache: fix symlink removal
>      bcache: move to drivers/md/
>      bcache: uplevel allocation of 'cached_dev' and 'cache'
>      md: add bcache personality
>
>
>  drivers/block/Kconfig            |    2
>  drivers/block/Makefile           |    1
>  drivers/md/Kconfig               |   14 +
>  drivers/md/Makefile              |    1
>  drivers/md/bcache/Kconfig        |    3
>  drivers/md/bcache/Makefile       |    2
>  drivers/md/bcache/alloc.c        |    0
>  drivers/md/bcache/bcache.h       |   39 ++++
>  drivers/md/bcache/bset.c         |    0
>  drivers/md/bcache/bset.h         |    0
>  drivers/md/bcache/btree.c        |   18 --
>  drivers/md/bcache/btree.h        |    0
>  drivers/md/bcache/debug.c        |    0
>  drivers/md/bcache/debug.h        |    0
>  drivers/md/bcache/io.c           |    0
>  drivers/md/bcache/journal.c      |    0
>  drivers/md/bcache/journal.h      |    0
>  drivers/md/bcache/md.c           |  374 ++++++++++++++++++++++++++++++++++++
>  drivers/md/bcache/request.c      |   24 +-
>  drivers/md/bcache/request.h      |    0
>  drivers/md/bcache/stats.c        |    0
>  drivers/md/bcache/stats.h        |    0
>  drivers/md/bcache/super.c        |  394 +++++++++-----------------------------
>  drivers/md/bcache/sysfs.c        |   49 -----
>  drivers/md/bcache/sysfs.h        |    0
>  drivers/md/bcache/trace.c        |    0
>  drivers/md/bcache/util.c         |    2
>  drivers/md/bcache/util.h         |    3
>  drivers/md/bcache/writeback.c    |    0
>  kernel/lockdep.c                 |    1
>  30 files changed, 539 insertions(+), 388 deletions(-)
>  rename drivers/{block/bcache/Kconfig => md/bcache/Kconfig} (95%)
>  rename drivers/{block/bcache/Makefile => md/bcache/Makefile} (77%)
>  rename drivers/{block/bcache/alloc.c => md/bcache/alloc.c} (100%)
>  rename drivers/{block/bcache/bcache.h => md/bcache/bcache.h} (94%)
>  rename drivers/{block/bcache/bset.c => md/bcache/bset.c} (100%)
>  rename drivers/{block/bcache/bset.h => md/bcache/bset.h} (100%)
>  rename drivers/{block/bcache/btree.c => md/bcache/btree.c} (99%)
>  rename drivers/{block/bcache/btree.h => md/bcache/btree.h} (100%)
>  rename drivers/{block/bcache/debug.c => md/bcache/debug.c} (100%)
>  rename drivers/{block/bcache/debug.h => md/bcache/debug.h} (100%)
>  rename drivers/{block/bcache/io.c => md/bcache/io.c} (100%)
>  rename drivers/{block/bcache/journal.c => md/bcache/journal.c} (100%)
>  rename drivers/{block/bcache/journal.h => md/bcache/journal.h} (100%)
>  create mode 100644 drivers/md/bcache/md.c
>  rename drivers/{block/bcache/request.c => md/bcache/request.c} (98%)
>  rename drivers/{block/bcache/request.h => md/bcache/request.h} (100%)
>  rename drivers/{block/bcache/stats.c => md/bcache/stats.c} (100%)
>  rename drivers/{block/bcache/stats.h => md/bcache/stats.h} (100%)
>  rename drivers/{block/bcache/super.c => md/bcache/super.c} (83%)
>  rename drivers/{block/bcache/sysfs.c => md/bcache/sysfs.c} (95%)
>  rename drivers/{block/bcache/sysfs.h => md/bcache/sysfs.h} (100%)
>  rename drivers/{block/bcache/trace.c => md/bcache/trace.c} (100%)
>  rename drivers/{block/bcache/util.c => md/bcache/util.c} (99%)
>  rename drivers/{block/bcache/util.h => md/bcache/util.h} (99%)
>  rename drivers/{block/bcache/writeback.c => md/bcache/writeback.c} (100%)
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bcache" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

This is very interesting,

I will play around with these this weekend. :)

Joseph.

-- 
Founder | Director | VP Research
Orion Virtualisation Solutions | www.orionvm.com.au | Phone: 1300 56
99 52 | Mobile: 0428 754 846
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html