Re: [PATCH 2/2] btrfs-progs: filesystem show of specified mounted disk should work

[Anand Jain <Anand.Jain@oracle.com>]

On 10/22/13 10:33 PM, David Sterba wrote:
> On Tue, Oct 22, 2013 at 01:53:22PM +0800, Anand Jain wrote:
>> @@ -386,7 +395,7 @@ static int btrfs_scan_kernel(void *search)
>>   static const char * const cmd_show_usage[] = {
>> -	"btrfs filesystem show [options] [<path>|<uuid>]",
>> +	"btrfs filesystem show [options|<path>|<uuid>]",
>
> Options should stay separate from the path/uuid, you're extending the
> syntax to accept a device:
>
> 	"btrfs filesystem show [options] [<path>|<uuid>|<device>]",
>
> I'm fixing it locally, let me know if this doesn't match what you've
> intended.

  I am confused, on how the options should be represented,
  but the internal design is as below.
  When either uuid/path/dev is provide the option
  -d/-m (which implies to read-disks or kernel) will not apply,
  since internally we would determine that based on whether the
  given disk/uuid is mounted/unmounted.
  so option -d/-m don't apply when last argument is provided.
  so the right commands are

  btrfs fi show <-- probe mount-points and then disks for unmounted btrfs
  btrfs fi show -d <-- probe all disks even they are mounted (for legacy 
purpose, as in the original design)
  btrfs fi show /dev/sda <-- use mount point if disk is mounted OR disk 
path if unmounted
  btrfs fi show -m <-- show only mounted btrfs.


Thanks, Anand