[libvirt] [PATCH 06/13] Rewrite way QEMU PCI addresses are allocated

[Matthias Bolte]

2010/2/1 Daniel P. Berrange <berrange at redhat.com>:
> The current QEMU code allocates PCI addresses incrementally starting
> at 4. This is not satisfactory because the user may have given some
> addresses in their XML config, which need to be skipped over when
> allocating addresses to remaining devices.
>
> It is thus neccessary to maintain a list of already allocated PCI
> addresses and then only allocate ones that remain unused. This is
> also required for domain device hotplug to work properly later.
>
> * src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Add APIs for creating
>  list of existing PCI addresses, and allocating new addresses.
>  Refactor address assignment to use this code
> * src/qemu/qemu_driver.c: Pull PCI address assignment up into the
>  qemuStartVMDaemon() method, as a prelude to moving it into the
>  'define' method. Update list of allocated addresses when connecting
>  to a running VM at daemon startup.
> * tests/qemuxml2argvtest.c, tests/qemuargv2xmltest.c,
>  tests/qemuxml2xmltest.c: Remove USB product test since all
>  passthrough is done based on address
> * tests/qemuxml2argvdata/qemuxml2argv-hostdev-usb-product.args,
>  tests/qemuxml2argvdata/qemuxml2argv-hostdev-usb-product.xml: Kil
>  unused data files
> ---

> diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
> index bbf49fd..9bfd181 100644
> --- a/src/qemu/qemu_conf.c
> +++ b/src/qemu/qemu_conf.c

> +
> +void qemuDomainPCIAddressSetFree(qemuDomainPCIAddressSetPtr addrs)
> +{
> +    if (!addrs)
> +        return;
> +
> +    virHashFree(addrs->used, qemuDomainPCIAddressSetFreeEntry);

Maybe add addrs->used = NULL after virHashFree to prevent potential
double frees or segfaults due to the dangling pointer.

ACK

Matthias