On 02/22/2016 07:35 AM, Ján Tomko wrote:
On Wed, Feb 17, 2016 at 05:33:45PM -0700, Jim Fehlig wrote:
xl/libxl already supports qemu's network-based block backends such as nbd and rbd. libvirt has supported configuring such <disk>s for long time too. This patch adds support for rbd disks in the libxl driver by generating a rbd device URL from the virDomainDiskDef object. The URL is passed to libxl via the pdev_path field of libxl_device_disk struct. libxl then passes the URL to qemu for cosumption by the rbd backend.
Signed-off-by: Jim Fehlig <jfehlig@suse.com> --- src/libxl/libxl_conf.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 191 insertions(+), 1 deletion(-)
ACK with the whitespace fix.
+ +static int +libxlMakeNetworkDiskSrc(virStorageSourcePtr src, char **srcstr) +{ + virConnectPtr conn = NULL; + char *secret = NULL; + char *username = NULL; + int ret = -1; + + *srcstr = NULL; + if (src->auth && src->protocol == VIR_STORAGE_NET_PROTOCOL_RBD) { + const char *protocol = virStorageNetProtocolTypeToString(src->protocol); + + username = src->auth->username; + if (!(conn = virConnectOpen("xen:///system"))) + goto cleanup; + Opening a connection feels out of place in this function, but I see it's already done for NICs.
It would be nice to reuse it as is done in the qemu driver.
Heh, this has turned out to be a PITA. Something like the attached patch works, but it still has the virConnectOpen in the libxlBuildDomainConfig call path. I would prefer to use the virConnect object associated with the request, instead of opening one in this code. I have some old, dusty patches (originally started by danpb) that provide unit tests for libxlBuildDomainConfig. E.g. domXML -> virDomainDef -> libxl_domain_config -> json representation -> compare with expected json. Code in this path attempting to open "xen:///" connections is likely to break many 'make check' setups :-). But fixing this is not easy given the current code structure. There is one place in particular that is rather troublesome - reboot. libxlDomainStart, and hence libxlBuildDomainConfig, are called when a reboot event is received from libxl (e.g. 'shutdown -r now' within a VM). As you might guess, there is no virConnect object associated with such request. The code needs reworked quite a bit to handle accessing a virConnect object while building a libxl_domain_config object. I'll work on this when dusting off the unit test patches, although it is not high in my queue. Maybe it would make a good libvirt GSoC project :-). Regards, Jim