[parted-devel] [PATCH] libparted/dasd: improve lvm/raid flag handling for DASD-CDL

[Wang Dong]

On 04/18/2017 02:02 AM, Phil Susi wrote:
> On 3/23/2017 10:11 PM, Wang Dong wrote:
>> From: André Wild <wild at linux.vnet.ibm.com>
>>
>> This commit corrects the reading of lvm/raid flags on DASD/CDL formatted
>> disks. Previously, users were not able to see what was the actual flags
>> stored on the disk. Also, warn users in interactive mode about existing
>> file systems when setting the lvm/raid flag. In script mode, this
>> warning is ignored.
> You say that previously users were not able to see what the actual flags
> stored on disk were, but the code this patch removes from dasd_read
> appears to do exactly that: translate the DASD information into lvm and
> raid flags.  You appear to have just added a warning that changing these
> flags might render an existing file system unusable.  How would it do
> that and why should we warn about this?
>
dasd_read just reads what the device got.
Previously, no matter what flag the disk got, if it has a file system,
the flag will never be read, although it got one. it is not good.
what we did is just reading what the disk got regardless of the 
existence of file system.

But when to set a flag on disk, if a file system exists, a warning will
raised. Because some flag does not work well along with file system, ex. 
lvm/raid.

-- 
Best regards. Wang Dong