s390: add personality support

Introduce personality support for Linux on z Systems to run
particular services with a 64-bit or 31-bit personality.

Makefile.am

@@ -1502,6 +1502,7 @@ EXTRA_DIST += \
 	test/exec-ignoresigpipe-yes.service \
 	test/exec-personality-x86-64.service \
 	test/exec-personality-x86.service \
+	test/exec-personality-s390.service \
 	test/exec-privatedevices-no.service \
 	test/exec-privatedevices-yes.service \
 	test/exec-privatetmp-no.service \

src/basic/util.c

@@ -5261,6 +5261,19 @@ unsigned long personality_from_string(const char *p) {
 
         if (streq(p, "x86"))
                 return PER_LINUX;
+
+#elif defined(__s390x__)
+
+        if (streq(p, "s390"))
+                return PER_LINUX32;
+
+        if (streq(p, "s390x"))
+                return PER_LINUX;
+
+#elif defined(__s390__)
+
+        if (streq(p, "s390"))
+                return PER_LINUX;
 #endif
 
         return PERSONALITY_INVALID;
@@ -5280,6 +5293,20 @@ const char* personality_to_string(unsigned long p) {
 
         if (p == PER_LINUX)
                 return "x86";
+
+#elif defined(__s390x__)
+
+        if (p == PER_LINUX)
+                return "s390x";
+
+        if (p == PER_LINUX32)
+                return "s390";
+
+#elif defined(__s390__)
+
+        if (p == PER_LINUX)
+                return "s390";
+
 #endif
 
         return NULL;

src/test/test-execute.c

@@ -77,10 +77,14 @@ static void test_exec_workingdirectory(Manager *m) {
 }
 
 static void test_exec_personality(Manager *m) {
-        test(m, "exec-personality-x86.service", 0, CLD_EXITED);
-
 #if defined(__x86_64__)
         test(m, "exec-personality-x86-64.service", 0, CLD_EXITED);
+
+#elif defined(__s390__)
+        test(m, "exec-personality-s390.service", 0, CLD_EXITED);
+
+#else
+        test(m, "exec-personality-x86.service", 0, CLD_EXITED);
 #endif
 }
 

test/exec-personality-s390.service

@@ -0,0 +1,7 @@
+[Unit]
+Description=Test for Personality=s390
+
+[Service]
+ExecStart=/bin/sh -c 'echo $(uname -m); exit $(test $(uname -m) = "s390")'
+Type=oneshot
+Personality=s390