nspawn: rename UNIFIED_CGROUP_HIERARCHY to SYSTEMD_NSPAWN_UNIFIED_HIERARCHY

We should never have used an unprefixed environment variable name.
All other systemd-nspawn variables have the "SYSTEMD_NSPAWN_" prefix,
and all other systemd variables have the "SYSTEMD_" prefix.

The new variable name takes precedence, but we fall back to checking the
old one. If only the old one is found, a warning is emitted.

In addition, SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="" is accepted as an override
to avoid looking for the old variable name.

We have a variable with the same name ($UNIFIED_CGROUP_HIERARCHY) in tests,
which governs both systemd-nspawn and qemu behaviour. It is not renamed.

diff --git a/docs/ENVIRONMENT.md b/docs/ENVIRONMENT.md
index 838cc7e4cf88eaa7666187c1cf491615abfd3411..c6a7f1babd32bc6ad045b1d39fb95ef8d057df2a 100644 (file)
--- a/docs/ENVIRONMENT.md
+++ b/docs/ENVIRONMENT.md
@@ -70,8 +70,8 @@ systemctl:
 
 systemd-nspawn:
 
-* `$UNIFIED_CGROUP_HIERARCHY=1` — if set, force nspawn into unified cgroup
-  hierarchy mode.
+* `$SYSTEMD_NSPAWN_UNIFIED_HIERARCHY=1` — if set, force nspawn into unified
+  cgroup hierarchy mode.
 
 * `$SYSTEMD_NSPAWN_API_VFS_WRITABLE=1` — if set, make /sys and /proc/sys and
   friends writable in the container. If set to "network", leave only

diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index f16a19525b514cbe2fcb9ac1c927cdf3691aff98..0737517ddc7c905bdd5091ab5f0e6c802600f347 100644 (file)
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -412,15 +412,27 @@ static int custom_mount_check_all(void) {
 }
 
 static int detect_unified_cgroup_hierarchy_from_environment(void) {
-        const char *e;
+        const char *e, *var = "SYSTEMD_NSPAWN_UNIFIED_HIERARCHY";
         int r;
 
         /* Allow the user to control whether the unified hierarchy is used */
-        e = getenv("UNIFIED_CGROUP_HIERARCHY");
-        if (e) {
+
+        e = getenv(var);
+        if (!e) {
+                static bool warned = false;
+
+                var = "UNIFIED_CGROUP_HIERARCHY";
+                e = getenv(var);
+                if (e && !warned) {
+                        log_info("$UNIFIED_CGROUP_HIERARCHY has been renamed to $SYSTEMD_NSPAWN_UNIFIED_HIERARCHY.");
+                        warned = true;
+                }
+        }
+
+        if (!isempty(e)) {
                 r = parse_boolean(e);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to parse $UNIFIED_CGROUP_HIERARCHY.");
+                        return log_error_errno(r, "Failed to parse $%s: %m", var);
                 if (r > 0)
                         arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
                 else

diff --git a/test/TEST-13-NSPAWN-SMOKE/test.sh b/test/TEST-13-NSPAWN-SMOKE/test.sh
index cc67cfa17d13b8897d37fad7d45aed0064a5ac87..f89bdca99ff85b06e0112d9932124750f515a83c 100755 (executable)
--- a/test/TEST-13-NSPAWN-SMOKE/test.sh
+++ b/test/TEST-13-NSPAWN-SMOKE/test.sh
@@ -113,16 +113,16 @@ function run {
 
     local _root="/var/lib/machines/unified-$1-cgns-$2-api-vfs-writable-$3"
     /create-busybox-container "$_root"
-    UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" -b
-    UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" --private-network -b
+    SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" -b
+    SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" --private-network -b
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" -U -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" -U -b; then
        [[ "$is_user_ns_supported" = "yes" && "$3" = "network" ]] && return 1
     else
        [[ "$is_user_ns_supported" = "no" && "$3" = "network" ]] && return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" --private-network -U -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" --private-network -U -b; then
        [[ "$is_user_ns_supported" = "yes" && "$3" = "yes" ]] && return 1
     else
        [[ "$is_user_ns_supported" = "no" && "$3" = "yes" ]] && return 1
@@ -131,42 +131,42 @@ function run {
     local _netns_opt="--network-namespace-path=/proc/self/ns/net"
 
     # --network-namespace-path and network-related options cannot be used together
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-interface=lo -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-interface=lo -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-macvlan=lo -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-macvlan=lo -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-ipvlan=lo -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-ipvlan=lo -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-veth -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-veth -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-veth-extra=lo -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-veth-extra=lo -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-bridge=lo -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-bridge=lo -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-zone=zone -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --network-zone=zone -b; then
        return 1
     fi
 
-    if UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --private-network -b; then
+    if SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" --private-network -b; then
        return 1
     fi
 
     # test --network-namespace-path works with a network namespace created by "ip netns"
     ip netns add nspawn_test
     _netns_opt="--network-namespace-path=/run/netns/nspawn_test"
-    UNIFIED_CGROUP_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" /bin/ip a | grep -v -E '^1: lo.*UP'
+    SYSTEMD_NSPAWN_UNIFIED_HIERARCHY="$1" SYSTEMD_NSPAWN_USE_CGNS="$2" SYSTEMD_NSPAWN_API_VFS_WRITABLE="$3" systemd-nspawn --register=no -D "$_root" "$_netns_opt" /bin/ip a | grep -v -E '^1: lo.*UP'
     local r=$?
     ip netns del nspawn_test
 

diff --git a/test/test-functions b/test/test-functions
index 2254bda467ae9fb7b1e7fff108ecc085c7d12815..359fd4026e460b68c855e5fe53f370701824a5ed 100644 (file)
--- a/test/test-functions
+++ b/test/test-functions
@@ -259,12 +259,12 @@ run_nspawn() {
     fi
 
     if [[ "$UNIFIED_CGROUP_HIERARCHY" = "hybrid" ]]; then
-        dwarn "nspawn doesn't support UNIFIED_CGROUP_HIERARCHY=hybrid, skipping"
+        dwarn "nspawn doesn't support SYSTEMD_NSPAWN_UNIFIED_HIERARCHY=hybrid, skipping"
         exit
     elif [[ "$UNIFIED_CGROUP_HIERARCHY" = "yes" || "$UNIFIED_CGROUP_HIERARCHY" = "no" ]]; then
-        _nspawn_cmd="env UNIFIED_CGROUP_HIERARCHY=$UNIFIED_CGROUP_HIERARCHY $_nspawn_cmd"
+        _nspawn_cmd="env SYSTEMD_NSPAWN_UNIFIED_HIERARCHY=$UNIFIED_CGROUP_HIERARCHY $_nspawn_cmd"
     elif [[ "$UNIFIED_CGROUP_HIERARCHY" = "default" ]]; then
-        _nspawn_cmd="env --unset=UNIFIED_CGROUP_HIERARCHY $_nspawn_cmd"
+        _nspawn_cmd="env --unset=UNIFIED_CGROUP_HIERARCHY --unset=SYSTEMD_NSPAWN_UNIFIED_HIERARCHY $_nspawn_cmd"
     else
         dfatal "Unknown UNIFIED_CGROUP_HIERARCHY. Got $UNIFIED_CGROUP_HIERARCHY, expected [yes|no|hybrid|default]"
         exit 1