On Wed, May 22, 2019 at 06:25:17PM +0200, Markus Armbruster wrote: > Stefano Garzarella <sgarz...@redhat.com> writes: > > > On Wed, May 8, 2019 at 1:44 PM Markus Armbruster <arm...@redhat.com> wrote: > >> > >> Stefano Garzarella <sgarz...@redhat.com> writes: > >> > >> > On Tue, May 07, 2019 at 08:34:51AM +0200, Markus Armbruster wrote: > [...] > >> >> Let me review support in drivers: > >> >> > >> >> * file (file-win32.c) > >> >> * iscsi > >> >> * nfs > >> >> * qed > >> >> * ssh > >> >> > >> >> - Reject all but PREALLOC_MODE_OFF > >> >> > >> >> * copy-on-read > >> >> * luks (crypto.c) > >> >> * raw > >> >> > >> >> - Pass through only > >> >> > >> >> * file host_cdrom host_device (file-posix.c) > >> >> > >> >> - Reject all but PREALLOC_MODE_OFF when shrinking and for non-regular > >> >> files > >> >> - Reject PREALLOC_MODE_FALLOC unless CONFIG_POSIX_FALLOCATE > >> >> - Reject PREALLOC_MODE_METADATA > >> >> > >> >> * gluster > >> >> > >> >> - Reject all but PREALLOC_MODE_OFF when shrinking > >> >> - Reject PREALLOC_MODE_FALLOC unless CONFIG_GLUSTERFS_FALLOCATE > >> >> - Reject PREALLOC_MODE_FULL unless CONFIG_GLUSTERFS_ZEROFILL > >> >> - Reject PREALLOC_MODE_METADATA > >> >> > >> >> * qcow2 > >> >> > >> >> - Reject all but PREALLOC_MODE_OFF when shrinking and with a backing > >> >> file > >> >> > >> >> * rbd with this patch > >> >> > >> >> - Reject all but PREALLOC_MODE_OFF when shrinking > >> >> - Reject PREALLOC_MODE_METADATA and PREALLOC_MODE_FALLOC > >> >> > >> >> * sheepdog > >> >> > >> >> - Reject PREALLOC_MODE_METADATA and PREALLOC_MODE_FALLOC > >> >> - Doesn't support shrinking > >> >> > >> >> * vdi > >> >> > >> >> - Reject PREALLOC_MODE_FALLOC and PREALLOC_MODE_FULL > >> >> - Doesn't support shrinking > >> >> > >> >> * blkdebug > >> >> * blklogwrites > >> >> * blkverify > >> >> * bochs > >> >> * cloop > >> >> * dmg > >> >> * ftp > >> >> * ftps > >> >> * http > >> >> * https > >> >> * luks > >> >> * nbd > >> >> * null-aio > >> >> * null-co > >> >> * nvme > >> >> * parallels > >> >> * qcow > >> >> * quorum > >> >> * replication > >> >> * throttle > >> >> * vhdx > >> >> * vmdk > >> >> * vpc > >> >> * vvfat > >> >> * vxhs > >> >> > >> >> - These appear not to use PreallocMode: they don't implement > >> >> .bdrv_co_truncate(), and either don't implement .bdrv_co_create() or > >> >> implement it without a prealloc parameter. > >> >> > >> >> Looks good to me. > >> >> > >> > > >> > Thanks for the analysis! > [...] > >> > If you agree, I can check and update the documentation of all drivers > >> > following > >> > your analysis. > >> > >> Yes, please! > > > > > > Hi Markus, > > I'm finally updating the documentation of preallocation modes > > supported by block drivers and protocols in qapi/block-core.json. > > As sheepdog and vdi I'm adding the supported values for each driver or > > protocol that supports 'preallocation' parameter during the creation, > > I'm also updating the '.help' in the QemuOptsList. > > > > My doubt is: where is better to put the documentation about > > preallocation modes supported during the resize? (e.g. some drivers > > support only PREALLOC_MODE_OFF when shrinking) > > As far as I can tell, no driver supports anything but PREALLOC_MODE_OFF > when shrinking. Suggest to ignore the shrinking case for now when > documenting. >
Okay, I'll ignore it for now. > I'm not sure I fully answered your question. Don't hesitate to ask for > more advice. Yes, your answer is what I was looking for :) Thanks, Stefano
