[dm-devel] [PATCH UPDATED] block: restore multiple bd_link_disk_holder() support

[Jun'ichi Nomura]

On 01/15/11 06:09, Milan Broz wrote:
> On 01/14/2011 05:10 PM, Tejun Heo wrote:
>> Commit e09b457b (block: simplify holder symlink handling) incorrectly
>> assumed that there is only one link at maximum.  dm may use multiple
>> links and expects block layer to track reference count for each link,
>> which is different from and unrelated to the exclusive device holder
>> identified by @holder when the device is opened.
>>
>> Remove the single holder assumption and automatic removal of the link
>> and revive the per-link reference count tracking.  The code
>> essentially behaves the same as before commit e09b457b sans the
>> unnecessary kobject reference count dancing.
>>
>> While at it, note that this facility should not be used by anyone else
>> than the current ones.  Sysfs symlinks shouldn't be abused like this
>> and the whole thing doesn't belong in the block layer at all.
>>
>> Signed-off-by: Tejun Heo <tj at kernel.org>
>> Reported-by: Milan Broz <mbroz at redhat.com>
>> Cc: Jun'ichi Nomura <j-nomura at ce.jp.nec.com>
>> Cc: Neil Brown <neilb at suse.de>
>> Cc: linux-raid at vger.kernel.org
>> Cc: Kay Sievers <kay.sievers at vrfy.org>
>> ---
>> Thanks for the test commands.  They were very helpful.  Can you please
>> test this one?
> 
> Hi,
> 
> yes, this one works for me. I run full lvm2 testsuite and no warnings.
> Thanks!
> 
> Tested-by: Milan Broz <mbroz at redhat.com>

Thanks Tejun, Milan!
If it passed my quick test and the lvm2 testsuite,
I have nothing to add here.
And the code looks ok, too.

-- 
Jun'ichi Nomura, NEC Corporation