Re: [dm-devel] [PATCH 0 of 5] MD: prepare RAID10 for inclusion in dm-raid.c

[Brassow Jonathan <jbrassow redhat com>]

On Jul 6, 2012, at 3:40 AM, CoolCold wrote:

> 
> 
> On Tue, Jun 26, 2012 at 12:44 PM, Jonathan Brassow <jbrassow redhat com> wrote:
> Neil,
> 
> Here's a couple patches that are necessary for MD before I can add
> RAID10 to the list of supported personalities through dm-raid.c:
>         1) md-raid10-rename-mirror_info.patch
>         2) md-raid1-rename-mirror_info.patch
>         3) md-move-IO_BLOCKED-to-md_h.patch
>         4) md-export-md_raid10_congested.patch
> 
> I'll send the patch that enables raid10 as a separate patch that depends
> on this patch set and a couple of DM patches.
> 
> Can you explain a bit more detailed for me, what is this about? I.e. from my point of view dm-raid and md-raid and fully separated but looks like I'm wrong and missing something.

drivers/md/dm-raid.c is a device-mapper target that provides access to the MD personalities.  So far, MD's RAID 1/4/5/6 have been made available to the device-mapper interface through this module.  We are laying the ground work here for RAID10 to be made available in the same way.

You may wish to have a look at linux/Documentation/device-mapper/dm-raid.txt for additional information.  Also note that in "[PATCH 4 of 4] MD RAID10: Export md_raid10_congested", I referenced a couple of other times that these types of changes were necessary.

Thanks,
 brassow