On Thu Apr 3, 2025 at 9:23 AM CEST, Fabian Grünbichler wrote: > On April 2, 2025 6:32 pm, Max Carrara wrote: > > On Mon Mar 31, 2025 at 5:12 PM CEST, Fabian Grünbichler wrote: > >> On March 26, 2025 3:20 pm, Max Carrara wrote: > >> > Add documentation for the following methods: > >> > - list_images > >> > - create_base > >> > - clone_image > >> > - alloc_image > >> > - free_image > >> > > >> > Signed-off-by: Max Carrara <m.carr...@proxmox.com> > >> > Co-authored-by: Maximiliano Sandoval <m.sando...@proxmox.com> > >> > --- > >> > src/PVE/Storage/PluginBase.pm | 111 ++++++++++++++++++++++++++++++++++ > >> > 1 file changed, 111 insertions(+) > >> > > >> > diff --git a/src/PVE/Storage/PluginBase.pm > >> > b/src/PVE/Storage/PluginBase.pm > >> > index b3ce684..37b1471 100644 > >> > --- a/src/PVE/Storage/PluginBase.pm > >> > +++ b/src/PVE/Storage/PluginBase.pm > >> > @@ -721,26 +721,137 @@ sub on_delete_hook { > >> > > >> > =cut > >> > > >> > +=head3 $plugin->list_images($storeid, \%scfg [, $vmid, \@vollist, > >> > \%cache]) > >> > + > >> > +B<REQUIRED:> Must be implemented in every storage plugin. > >> > + > >> > +Returns a listref of all disk images of a storage. If the storage does > >> > not > >> > +support storing disk images, returns an empty listref. > >> > + > >> > +Optionally, if C<\@vollist> is provided, return only disks whose volume > >> > ID is > >> > +within C<\@vollist>. Note that this usually has higher precedence than > >> > +C<$vmid>. > > > > Upfront note: Unless I otherwise comment something, I agree with you. > > Just sparing myself from writing and you from reading too many ACKs :P > > > >> > >> what does usually mean? what does $vmid do? > > > > Sorry, this got lost when tossing out some redundant paragraphs here. > > > > The "usually" can be dropped; C<$vmid> is the guest's ID (mentioned in > > the DESCRIPTION in patch 01) and unless C<\@vollist> is provided, the > > images that the given C<$vmid> owns will be returned. > > in case that wasn't obvious - I know what $vmid is (and also what it > does) - it should be explained to readers that don't (yet). > > So I think this should say something like: > > If C<$vmid> is set, only images owned by that VMID must be included in > the return value. > > If C<\@vollist> is set and not empty, the return value must be filtered > using the contained volids. > > If both C<$vmid> and C<\@vollist> are set, only C<\@vollist> should be > honored.
Thanks for the suggestion, that's actually much better. I also agree with the other suggestions further below. > > and about that last part - do we actually have callers that set both? if > not, should we instead recommend treating it as an error and document it > as such? I'll revisit the call sites again and see whether we actually do, just to be sure. The current code at least doesn't treat it as an error. > > >> > + > >> > +C<die>s in case of errors. > >> > + > >> > +This method may reuse L<< cached information via C<\%cache>|/"CACHING > >> > EXPENSIVE OPERATIONS" >>. > >> > + > >> > +The returned listref has the following structure: > >> > + > >> > + [ > >> > + { > >> > + ctime => "1689163322", # creation time as unix timestamp > >> > + format => "raw", > >> > + size => 8589934592, # in bytes! > >> > + vmid => 101, > >> > + volid => "local-lvm:base-101-disk-0", # volume ID, > >> > storage-specific > >> > + }, > >> > + # [...] > >> > + ] > >> > + > >> > +=cut > >> > + > >> > sub list_images { > >> > my ($class, $storeid, $scfg, $vmid, $vollist, $cache) = @_; > >> > croak "implement me in sub-class\n"; > >> > } > >> > > >> > +=head3 $plugin->create_base($storeid, \%scfg, $volname) > >> > + > >> > +B<OPTIONAL:> May be implemented in a storage plugin. > >> > + > >> > +Creates a base volume from an existing volume, allowing the volume to be > >> > >> this is misleading - it doesn't create a base volume from an existing > >> volume, it *converts* an existing volume into a base volume! > > > > Oh dang, thanks for pointing this out! Sorry for the oversight. > > > >> > >> > +L<< cloned|/"$plugin->clone_image(...)" >>. This cloned volume (usually > >> > +a disk image) may then be used as a base for the purpose of creating > >> > linked > >> > >> this is wrong? there is no cloned volume yet? and all of this only > >> applies to images and not other volumes? > >> > >> > +clones. See L<C<PVE::Storage::LvmThinPlugin>> and > >> > +L<C<PVE::Storage::ZFSPoolPlugin>> for example implementations. > >> > + > >> > +On completion, returns the name of the new base volume (the new > >> > C<$volname>). > >> > + > >> > +This method is called in the context of C<L<< > >> > cluster_lock_storage()|/"cluster_lock_storage(...)" >>>, > >> > +i.e. when the storage is B<locked>. > >> > >> Shouldn't this say that it *should* be called in a locked context? > >> > >> > + > >> > +=cut > >> > + > >> > sub create_base { > >> > my ($class, $storeid, $scfg, $volname) = @_; > >> > croak "implement me in sub-class\n"; > >> > } > >> > > >> > +=head3 $plugin->clone_image($scfg, $storeid, $volname, $vmid [, $snap]) > >> > + > >> > +=head3 $plugin->clone_image(...) > >> > + > >> > +B<REQUIRED:> Must be implemented in every storage plugin. > >> > >> not really? there's a feature guard for it, so only storage plugins that > >> support it should ever get it called anyway.. > >> > >> what does $vmid mean? > > > > See above; the guest's ID. Since it was unclear, the parameter should > > probably be explained here (and also above) instead of (just) in the > > DESCRIPTION section. > > I know what a vmid is ;) the question is what does this parameter *mean* > for this particular method? > > C<$vmid> contains the owner of the new volume, which must be encoded in > the returned volid. > > or something like that? > > >> > + > >> > +Clones a disk image or a snapshot of an image, returning the name of > >> > the new > >> > +image (the new C<$volname>). Note that I<cloning> here means to create > >> > a linked > >> > +clone and not duplicating an image. See > >> > L<C<PVE::Storage::LvmThinPlugin>> and > >> > +L<C<PVE::Storage::ZFSPoolPlugin>> for example implementations. > >> > >> then why not start with > >> > >> "Creates a linked clone of an existing disk image or snapshot of an > >> image" > >> > >> ? maybe also include that unless the linked clone is 100% independent > >> from the base (only true for LVM thin atm?), the new volid should encode > >> the base->clone relation in the volname? > >> > >> > + > >> > +C<die>s in case of an error of if the underlying storage doesn't support > >> > >> s/of/or/ > >> > >> > +cloning images. > >> > + > >> > +This method is called in the context of C<L<< > >> > cluster_lock_storage()|/"cluster_lock_storage(...)" >>>, > >> > +i.e. when the storage is B<locked>. > >> > >> same as above > >> > >> > + > >> > +=cut > >> > + > >> > sub clone_image { > >> > my ($class, $scfg, $storeid, $volname, $vmid, $snap) = @_; > >> > croak "implement me in sub-class\n"; > >> > } > >> > > >> > +=head3 $plugin->alloc_image($storeid, $scfg, $vmid, $fmt, $name, $size) > >> > + > >> > +B<REQUIRED:> Must be implemented in every storage plugin. > >> > + > >> > +Allocates a disk image with the given format C<$fmt> and C<$size> in > >> > bytes, > >> > +returning the name of the new image (the new C<$volname>). See > >> > +C<L<< plugindata()|/"$plugin->plugindata()" >>> for all disk formats. > >> > + > >> > +Optionally, if given, set the name of the image to C<$name>. If > >> > C<$name> isn't > >> > +provided, the next name should be determined via C<L<< > >> > find_free_diskname()|/"$plugin->find_free_diskname(...)" >>>. > >> > >> a suitable name should be automatically generated, unless we really want > >> to stabilize find_free_diskname as part of the API.. > >> > >> what does $vmid mean? > > here as well, similar to clone_image above > > > _______________________________________________ > pve-devel mailing list > pve-devel@lists.proxmox.com > https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel