[pve-devel] [PATCH pve-manager 1/2] configs: add udev helper for pinning virtual function names

[Stefan Hanreich]

This commmit adds a udev rule that triggers for every network device
that gets added. It checks if the network device is a VF and if the
parent device is pinned. If it is pinned, then generate a new name for
the VF which consists of the pinned name of the parent device, as well
as the index of the VF.

It relies on the network device driver exposing the information via
sysfs, which was the case in my tests for mlx5_core, igb and bnxt_en.

Specifically it checks if a device is a virtual function by checking
for the existence of:

  /sys/class/net/<iface>/device/physfn

It then follows that symlink and infers the vf index by looking at the
virtfnX symlinks in the folder above.

Signed-off-by: Stefan Hanreich <s.hanreich at proxmox.com>
---
 configs/Makefile                        |  4 ++-
 configs/virtual-function-pinning-helper | 37 +++++++++++++++++++++++++
 configs/virtual-function-pinning.rules  |  1 +
 3 files changed, 41 insertions(+), 1 deletion(-)
 create mode 100644 configs/virtual-function-pinning-helper
 create mode 100644 configs/virtual-function-pinning.rules

diff --git a/configs/Makefile b/configs/Makefile
index 57d61a0bd..6b89e8b3a 100644
--- a/configs/Makefile
+++ b/configs/Makefile
@@ -6,7 +6,7 @@ country.dat: country.pl
 	./country.pl > country.dat
 
 .PHONY: install
-install: country.dat vzdump.conf pve-sources.sources pve-initramfs.conf pve-blacklist.conf pve.logrotate
+install: country.dat vzdump.conf pve-sources.sources pve-initramfs.conf pve-blacklist.conf pve.logrotate virtual-function-pinning.rules virtual-function-pinning-helper
 	install -D -m 0644 pve.logrotate $(DESTDIR)/etc/logrotate.d/pve
 	install -D -m 0644 pve-sources.sources $(DESTDIR)/etc/apt/sources.list.d/pve-enterprise.sources
 	install -D -m 0644 pve-blacklist.conf $(DESTDIR)/etc/modprobe.d/pve-blacklist.conf
@@ -14,6 +14,8 @@ install: country.dat vzdump.conf pve-sources.sources pve-initramfs.conf pve-blac
 	install -D -m 0644 pve-initramfs.conf $(DESTDIR)/etc/initramfs-tools/conf.d/pve-initramfs.conf
 	install -D -m 0644 country.dat $(DESTDIR)/usr/share/$(PACKAGE)/country.dat
 	install -D -m 0644 proxmox-ve-default.link $(DESTDIR)/usr/lib/systemd/network/99-default.link.d/proxmox-mac-address-policy.conf
+	install -D -m 0644 virtual-function-pinning.rules $(DESTDIR)/usr/lib/udev/rules.d/70-virtual-function-pinning.rules
+	install -D -m 0755 virtual-function-pinning-helper $(DESTDIR)/usr/lib/udev/virtual-function-naming-helper
 
 clean:
 	rm -f country.dat
diff --git a/configs/virtual-function-pinning-helper b/configs/virtual-function-pinning-helper
new file mode 100644
index 000000000..9a8a95b54
--- /dev/null
+++ b/configs/virtual-function-pinning-helper
@@ -0,0 +1,37 @@
+#!/bin/sh
+set -eu
+
+DEVICE_SYSFS_PCI_PATH=$(realpath "/sys${DEVPATH}/../..");
+
+if [ ! -L "$DEVICE_SYSFS_PCI_PATH/physfn" ]; then
+    exit;
+fi
+
+PHYSFN_SYSFS_PCI_PATH=$(realpath "${DEVICE_SYSFS_PCI_PATH}/physfn");
+PHYSFN_IFACE_NAME=$(ls "${PHYSFN_SYSFS_PCI_PATH}/net")
+
+# interface is not pinned
+if [ ! -f "/usr/local/lib/systemd/network/50-pve-${PHYSFN_IFACE_NAME}.link" ]; then
+    exit;
+fi
+
+# pin is not applied - or interface doesn't exist
+if ! ip link show "$PHYSFN_IFACE_NAME" > /dev/null 2>&1 ; then
+    exit;
+fi
+
+DEVICE_PCI_ID=$(basename "$DEVICE_SYSFS_PCI_PATH");
+
+for file in $(find "${PHYSFN_SYSFS_PCI_PATH=$}/" -maxdepth 1 -type l -name 'virtfn*' ); do
+    VF_PCI_ID=$(basename "$(realpath "$file")");
+
+    if [ "$DEVICE_PCI_ID" = "$VF_PCI_ID" ]; then
+        VF_INDEX=$(basename "$file" | grep -Eo '[[:digit:]]+$' -);
+        echo "${PHYSFN_IFACE_NAME}v${VF_INDEX}";
+        exit;
+    fi
+done
+
+echo "interface seems to be a VF of ${PHYSFN_IFACE_NAME}, but could not find the VF index" 1>&2;
+exit;
+
diff --git a/configs/virtual-function-pinning.rules b/configs/virtual-function-pinning.rules
new file mode 100644
index 000000000..dc2224886
--- /dev/null
+++ b/configs/virtual-function-pinning.rules
@@ -0,0 +1 @@
+SUBSYSTEM=="net",ACTION=="add",PROGRAM=="/usr/lib/udev/virtual-function-naming-helper",NAME="%c"
-- 
2.39.5