[libvirt] [PATCH] virStorageVolWipe: Document that wiping journaled FS is useless

[Michal Privoznik]

On 18.12.2015 20:30, John Ferlan wrote:
> 
> 
> On 12/17/2015 05:10 AM, Michal Privoznik wrote:
>> So you have a libvirt volume that you want to wipe out. But lets
>> say that the volume is actually a file stored on a journaled
>> filesystem. Overwriting it with zeroes or a pattern does not mean
>> that corresponding physical location on the disk is overwritten
>> too, due to journaling. It's the same story with network based
>> volumes, copy-on-write filesystems, and so on. Since there is no
>> way that an userland application can write onto specific areas on
>> disk, all that we can do is document the fact.
>>
>> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
>> ---
>>  src/libvirt-storage.c | 16 +++++++++++++---
>>  1 file changed, 13 insertions(+), 3 deletions(-)
>>
> 
> Seems reasonable.  Is there an associated bz?

None that I know of. It's just that I've came across some discussion in
the office about volWipe and it just appeared to me that we ought to
have this documented.

Michal