On Fri, May 08, 2015 at 10:26:22PM +0800, Chen Hanxiao wrote: > > On 04/30/2015 06:51 PM, Chen, Hanxiao wrote: > > Hi, Rich > > > >> -----Original Message----- > >> From: Richard W.M. Jones [mailto:[email protected]] > >> Sent: Wednesday, April 29, 2015 7:04 PM > >> To: Chen, Hanxiao/陈 晗霄 > >> Cc: [email protected] > >> Subject: Re: [Libguestfs] [PATCH 00/10] virt-resize: add support for > >> resizing MBR > >> logical partitions > >> > >> On Wed, Apr 29, 2015 at 09:19:24AM +0000, Chen, Hanxiao wrote: > >>> commit 6e989fd709fea37430398cbb7c01c52cd44bd1ac already did this: > >>> we had p_mbr_p_type : partition_type in type partition. > >>> Like what MBR/EBR did, this patchset use `partition_type`: > >>> > >>> /dev/sda3: > >>> partition data: 3 210763776-420478975 (209715200 bytes) > >>> bootable: false > >>> partition ID: 0x5 > >>> content: extended partition > >>> label: (none) > >>> GUID: (none) > >>> *partition type: extended* > >>> /dev/sda5: > >>> partition data: 5 211812352-222298111 (10485760 bytes) > >>> bootable: false > >>> partition ID: 0x83 > >>> content: unknown data > >>> label: (none) > >>> GUID: (none) > >>> *partition type: logical* > >>> > >>> As we could only had one extended partition, > >>> all logical partitions belong to that extended partition, > >>> so current type partition of virt-resize can reflect logical/extended > >>> partition > >> model. > >> > >> The specific problem is that the extended partition (eg /dev/sda3) > >> contains the logical partition (/dev/sda5). Having a flat list > >> doesn't express that at all. > > We had at most 4 PTE in MBR, in PTE, a partition type is on +04h, > > value 05h or 0fh shows it's an extended partition. > > From extended partition's EBR, we got logical partitions. > > > > sda1-- sda2 -- sda3 -- sda4 > > ^ > > | > > sda5 -- sda6 > > > > I think we do not need to show this specially, > > just use the original design: > > logical partitions existed in extended partition, an implicit relations. > > > > So a flat list can do this: > > We mark each members, then a tree view above could be rebuilt precisely > > from plat list. > Hi, Rich > > Any comments on this?
As I said in my original email, my opinion is still that the code would be clearer if it expressed the peculiar structure of MBR extended/logical partitions directly in the structures. There's really a high hurdle for these changes. They must be: - easy to review - absolutely not break existing uses of virt-resize We're nowhere near there at the moment. There's no good testing, there are no patches for review which look sound. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-builder quickly builds VMs from scratch http://libguestfs.org/virt-builder.1.html _______________________________________________ Libguestfs mailing list [email protected] https://www.redhat.com/mailman/listinfo/libguestfs
