Re: [Libvir] PATCH: support Xen 3.0.5

I've been doing some testing with current xen-unstable (ie what will very shortly be 3.0.5) and came across a whole bunch of things which needed fixing - some expected, others not expected. The attached patch addresses the following issues: - Many of the hypercalls have their structs changed so that int64_t or 'foo *' members are always 64-bit aligned even on 32-bit platforms. This is part of the work to allow 32-bit Dom0/DomU to work on 64-bit hypervisor. For the int64_t types I had to annotate with __attribute__((aligned(8))). This did not work for pointer data types, so I for those I had to do a more complex hack with union { foo *v; int64_t pad __attribute__((aligned(8))) } This matches what is done in the public (BSD licensed) Xen HV header files. We already had ways to deal with v0 vs v2 hypercalls structs. This change is still techincally v2, but just a minor revision of the domctl or sysctl interfaces. Thus I have named the extra structs v2d5 or v2s3 to indicated hypercall version 2, domctl version 5 or hypercall version 2, sysctl version 3 respectively. - The 'flags' field in the getdomaininfo hypercall now has an extra flag defined '(1<<1)' which was previously not used, is now used to indicate that the guest is HVM. Thus when fetching domain state, we have to mask out that flag, otherwise we'll never match the correct paused/running/ blocked/etc states. - In the xenHypervisorNumOfDomains method, under certain scenarios we will re-try the hypercall, allocating a bigger memory buffer. Well due to the ABI alignment changes we hit that scenario everytime, and ended up allocating a multi-GB buffer :-) The fixed structs sort this out, but as a preventative measure for any future HV changes the patch will break out of the loop at the 10,000 guest mark to avoid allocating GB of memory. - The unified Xen driver broke the GetVCPUs method - it was mistakenly checking for return value == 0, instead of > 0. Trivial fix. - The method to open the XenD connection was calling xenDaemonGetVersion to test if the connection succeeded. But then also calling the xend_detect_config_version which does pretty much same thing. So I removed the former, and now we only do the latter as a 'ping' test when opening. This removes 1 HTTP GET which is worthwhile performance boost given how horrifically slow XenD is. - The HVM SEXPR for configuring the VNC / SDL graphics is no longere part of the (image) block. it now matches the PVFB graphics config and is an explicit (vfb) block within the (devices) block. So if xend_config_format >= 4 we use the new style config - this is assuming upstream XenD is patched to increment xend_config_format from 3 to 4 - I send a patch & am confident it will be applied very shortly. - The QEMU device model allows a user to specify multiple devices for the boot order, eg 'andc' to indicated 'floppy', 'network' 'cdrom', 'disk'. We assumed it was a single letter only. I now serialize this into multiple <boot dev='XXX'/> elements, ordered according to priority. The XML -> SEXPR conversion allows the same. I've tested all this on a 32-bit Dom0 running on 32-bit HV, and 64-bit HV, but not tested a 64-bit Dom0 on 64-bit HV. I'm pretty sure it'll work,but if anyone is runnning 64-on-64 please test this patch. Regards, Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|