Re: [libvirt] [PATCH 2/2] nodedev: report maxCount for virtual_functions capability

A PCI device may have the capability to setup virtual functions (VFs) but have them currently all disabled. Prior to this patch, if that was the case the the node device XML for the device wouldn't report any

virtual_functions capability. With this patch, if a file called "sriov_totalvfs" is found in the device's sysfs directory, its contents will be interpreted as a decimal number, and that value will be reported as "maxCount" in a capability element of the device's XML, e.g.: <capability type='virtual_functions' maxCount='7'/> This will be reported regardless of whether or not any VFs are currently enabled for the device. NB: sriov_numvfs (the number of VFs currently active) is also available in sysfs, but that value is implied by the number of items in the list that is inside the capability element, so there is no reason to explicitly provide it as an attribute. sriov_totalvfs and sriov_numvfs are available in kernels at least as far back as the 2.6.32 that is in RHEL6.7, but in the case that they simply aren't there, libvirt will behave as it did prior to this patch - no maxCount will be displayed, and the virtual_functions capability will be absent from the device's XML when 0 VFs are enabled. --- src/network/bridge_driver.c | 5 +++-- src/node_device/node_device_linux_sysfs.c | 7 +++++-- src/util/virnetdev.c | 9 ++++++--- src/util/virnetdev.h | 5 +++-- src/util/virpci.c | 30 ++++++++++++++++++++++++++---- src/util/virpci.h | 5 +++-- 6 files changed, 46 insertions(+), 15 deletions(-)