95resume: Do not resume on iSCSI, FCoE or NBD

The iSCSI configuration is started after dracut checks for resume,
so we run into a timeout here. Additionally it's questionable if
resume on iSCSI makes sense (or is even supported on the platform).

Same holds true for Network Block Devices and FcOE, cover those as well

References: bsc#999663

Original-patch-by: Hannes Reinecke <[email protected]>
Signed-off-by: Daniel Molkentin <[email protected]>

dracut-functions.sh

@@ -842,3 +842,47 @@ ip_params_for_remote_addr() {
     fi
 
 }
+
+# block_is_nbd <maj:min>
+# Check whether $1 is an nbd device
+block_is_nbd() {
+    [[ -b /dev/block/$1 && $1 == 43:* ]]
+}
+
+# block_is_iscsi <maj:min>
+# Check whether $1 is an nbd device
+block_is_iscsi() {
+    local _dir
+    local _dev=$1
+    [[ -L "/sys/dev/block/$_dev" ]] || return
+    _dir="$(readlink -f "/sys/dev/block/$_dev")" || return
+    until [[ -d "$_dir/sys" || -d "$_dir/iscsi_session" ]]; do
+        _dir="$_dir/.."
+    done
+    [[ -d "$_dir/iscsi_session" ]]
+}
+
+# block_is_fcoe <maj:min>
+# Check whether $1 is an FCoE device
+# Will not work for HBAs that hide the ethernet aspect
+# completely and present a pure FC device
+block_is_fcoe() {
+    local _dir
+    local _dev=$1
+    [[ -L "/sys/dev/block/$_dev" ]] || return
+    _dir="$(readlink -f "/sys/dev/block/$_dev")"
+    until [[ -d "$_dir/sys" ]]; do
+        _dir="$_dir/.."
+        if [[ -d "$_dir/subsystem" ]]; then
+            subsystem=$(basename $(readlink $_dir/subsystem))
+            [[ $subsystem == "fcoe" ]] && return 0
+        fi
+    done
+    return 1
+}
+
+# block_is_netdevice <maj:min>
+# Check whether $1 is a net device
+block_is_netdevice() {
+    block_is_nbd "$1" || block_is_iscsi "$1" || block_is_fcoe "$1"
+}

modules.d/95iscsi/module-setup.sh

@@ -9,20 +9,9 @@ check() {
     # If hostonly was requested, fail the check if we are not actually
     # booting from root.
 
-    is_iscsi() {
-        local _dev=$1
-
-        [[ -L "/sys/dev/block/$_dev" ]] || return
-        cd "$(readlink -f "/sys/dev/block/$_dev")"
-        until [[ -d sys || -d iscsi_session ]]; do
-            cd ..
-        done
-        [[ -d iscsi_session ]]
-    }
-
     [[ $hostonly ]] || [[ $mount_needs ]] && {
         pushd . >/dev/null
-        for_each_host_dev_and_slaves is_iscsi
+        for_each_host_dev_and_slaves block_is_iscsi
         local _is_iscsi=$?
         popd >/dev/null
         [[ $_is_iscsi == 0 ]] || return 255
@@ -223,6 +212,7 @@ install() {
     inst_hook cmdline 90 "$moddir/parse-iscsiroot.sh"
     inst_hook cleanup 90 "$moddir/cleanup-iscsi.sh"
     inst "$moddir/iscsiroot.sh" "/sbin/iscsiroot"
+
     if ! dracut_module_included "systemd"; then
         inst "$moddir/mount-lun.sh" "/bin/mount-lun.sh"
     else

modules.d/95nbd/module-setup.sh

@@ -7,11 +7,9 @@ check() {
     # if an nbd device is not somewhere in the chain of devices root is
     # mounted on, fail the hostonly check.
     [[ $hostonly ]] || [[ $mount_needs ]] && {
-        is_nbd() { [[ -b /dev/block/$1 && $1 == 43:* ]] ;}
-
         _rootdev=$(find_root_block_device)
         [[ -b /dev/block/$_rootdev ]] || return 1
-        check_block_and_slaves is_nbd "$_rootdev" || return 255
+        check_block_and_slaves block_is_nbd "$_rootdev" || return 255
     }
     require_binaries nbd-client || return 1
 

modules.d/95resume/module-setup.sh

@@ -2,9 +2,18 @@
 
 # called by dracut
 check() {
+    swap_on_netdevice() {
+        local _dev
+        for _dev in "${swap_devs[@]}"; do
+            block_is_netdevice $_dev && return 0
+        done
+        return 1
+    }
+
     # Only support resume if hibernation is currently on
+    # and no swap is mounted on a net device
     [[ $hostonly ]] || [[ $mount_needs ]] && {
-        [[ "$(cat /sys/power/resume)" == "0:0" ]] && return 255
+        swap_on_netdevice || [[ "$(cat /sys/power/resume)" == "0:0" ]] && return 255
     }
 
     return 0