Add a --hostonly-nics option

Currently when network is enabled, dracut will install all network drivers that are currently loaded, but some time only one NIC is needed for the initramfs. So for strict hostonly mode, add a --hostonly-nics option, user can provide a list of NICs to be enabled, and only needed drivers for specifed NICs will be installed so save space. Signed-off-by: Kairui Song <[email protected]>
dracutdevs · Oct 26, 2020 · 1e92f72 · 1e92f72
1 parent e4483e5
commit 1e92f72
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Showing 2 changed files with 21 additions and 3 deletions.
diff --git a/dracut.sh b/dracut.sh
@@ -175,6 +175,8 @@ Creates initial ramdisk images for preloading modules
   --hostonly-i18n       Install only needed keyboard and font files according
                         to the host configuration (default).
   --no-hostonly-i18n    Install all keyboard and font files available.
+  --hostonly-nics [LIST]
+                        Only enable listed NICs in the initramfs.
   --persistent-policy [POLICY]
                         Use [POLICY] to address disks and partitions.
                         POLICY can be any directory name found in /dev/disk.
@@ -424,6 +426,7 @@ rearrange_params()
         --long kernel-image: \
         --long no-hostonly-i18n \
         --long hostonly-i18n \
+        --long hostonly-nics: \
         --long no-machineid \
         --long version \
         -- "$@")
@@ -587,6 +590,8 @@ while :; do
                        hostonly_cmdline_l="yes" ;;
         --hostonly-i18n)
                        i18n_install_all_l="no" ;;
+        --hostonly-nics)
+                       hostonly_nics_l+=("$2");           PARMS_TO_STORE+=" '$2'"; shift;;
         --no-hostonly-i18n)
                        i18n_install_all_l="yes" ;;
         --no-hostonly-cmdline)
@@ -755,6 +760,7 @@ unset NPATH
 (( ${#fstab_lines_l[@]} )) && fstab_lines+=( "${fstab_lines_l[@]}" )
 (( ${#install_items_l[@]} )) && install_items+=" ${install_items_l[@]} "
 (( ${#install_optional_items_l[@]} )) && install_optional_items+=" ${install_optional_items_l[@]} "
+(( ${#hostonly_nics_l[@]} )) && hostonly_nics+=" ${hostonly_nics_l[@]} "
 
 # these options override the stuff in the config file
 (( ${#dracutmodules_l[@]} )) && dracutmodules="${dracutmodules_l[@]}"

diff --git a/modules.d/90kernel-network-modules/module-setup.sh b/modules.d/90kernel-network-modules/module-setup.sh
@@ -14,15 +14,27 @@ depends() {
 installkernel() {
     # Include wired net drivers, excluding wireless
     local _arch=${DRACUT_ARCH:-$(uname -m)}
-    local _net_drivers='eth_type_trans|register_virtio_device|usbnet_open'
+    local _net_symbols='eth_type_trans|register_virtio_device|usbnet_open'
     local _unwanted_drivers='/(wireless|isdn|uwb|net/ethernet|net/phy|net/team)/'
+    local _net_drivers
 
     if [ "$_arch" = "s390" -o "$_arch" = "s390x" ]; then
-        _s390drivers="=drivers/s390/net"
+        dracut_instmods -o -P ".*${_unwanted_drivers}.*" -s "$_net_symbols" "=drivers/s390/net"
     fi
 
-    dracut_instmods -o -P ".*${_unwanted_drivers}.*" -s "$_net_drivers" "=drivers/net" ${_s390drivers:+"$_s390drivers"}
+    if [[ $hostonly_mode == 'strict' ]] && [[ $hostonly_nics ]]; then
+        for _nic in $hostonly_nics; do
+            _net_drivers=$(get_dev_module /sys/class/net/$_nic)
+            if ! [[ $_net_drivers ]]; then
+                derror "--hostonly-nics contains invalid NIC '$_nic'"
+                continue
+            fi
+            hostonly="" instmods $_net_drivers
+        done
+        return 0
+    fi
 
+    dracut_instmods -o -P ".*${_unwanted_drivers}.*" -s "$_net_symbols" "=drivers/net"
     #instmods() will take care of hostonly
     instmods \
         =drivers/net/phy \