Re: [libvirt] [PATCH v3 02/18] blockjob: shuffle block rebase code

On 08/31/14 06:02, Eric Blake wrote: > The existing virDomainBlockRebase code rejected the combination of > _RELATIVE and _COPY flags, but only by accident. It makes sense, > at least for the case of _SHALLOW and not _REUSE_EXT, but to > implement it, libvirt would have to pre-create the file with a > relative backing name. > > Meanwhile, the code to forward on to the block copy code is getting > longer, and reorganising the function to have the block pull done > early makes it easier to add even more block copy prep code. > > This patch should have no semantic difference other than the quality > of the error message on the unsupported flag combination. > > * src/qemu/qemu_driver.c (qemuDomainBlockRebase): Reorder code, > and improve error message of relative copy. > > Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; > --- > src/qemu/qemu_driver.c | 47 ++++++++++++++++++++++++++++++++--------------- > 1 file changed, 32 insertions(+), 15 deletions(-) > > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c > index 239a300..177d3e4 100644 > --- a/src/qemu/qemu_driver.c > +++ b/src/qemu/qemu_driver.c > @@ -15467,6 +15467,8 @@ qemuDomainBlockRebase(virDomainPtr dom, const char *path, const char *base, > unsigned long bandwidth, unsigned int flags) > { > virDomainObjPtr vm; > + const char *format = NULL; > + int ret = -1; > > virCheckFlags(VIR_DOMAIN_BLOCK_REBASE_SHALLOW | > VIR_DOMAIN_BLOCK_REBASE_REUSE_EXT | > @@ -15477,22 +15479,37 @@ qemuDomainBlockRebase(virDomainPtr dom, const char *path, const char *base, > if (!(vm = qemuDomObjFromDomain(dom))) > return -1; > > - if (virDomainBlockRebaseEnsureACL(dom->conn, vm->def) < 0) { > + if (virDomainBlockRebaseEnsureACL(dom->conn, vm->def) < 0) > + goto cleanup; > + > + /* For normal rebase (enhanced blockpull), the common code handles > + * everything, including vm cleanup. */ > + if (!(flags & VIR_DOMAIN_BLOCK_REBASE_COPY)) > + return qemuDomainBlockJobImpl(vm, dom->conn, path, base, bandwidth, > + NULL, BLOCK_JOB_PULL, flags); > + > + /* If we got here, we are doing a block copy rebase. */ > + if (flags & VIR_DOMAIN_BLOCK_REBASE_COPY_RAW) > + format = "raw"; > + > + /* XXX: If we are doing a shallow copy but not reusing an external > + * file, we should attempt to pre-create the destination with a > + * relative backing chain instead of qemu's default of absolute */ > + if (flags & VIR_DOMAIN_BLOCK_REBASE_RELATIVE) { > + virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s", > + _("Relative backing during copy not supported yet")); > + goto cleanup; If you'd shuffle this more up and add (flags & VIR_DOMAIN_BLOCK_REBASE_COPY) you'd be able to get rid of the cleanup section entirely.

> + } > +