fstab-generator: use more appropriate checks for swap and device availability

We always should use the same checks when deciding whether swap support
and mounting of devices is supported. Hence, let's make
fstab-generator's logic more similar to the usual logic we follow:

a) Look for /proc/swaps and no container support before activating
swaps.

b) Look for /sys being writable befire supporting device mounts.

diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 1f345949289902270a98adaa96b478702a689db9..496657bdc176a25b170788d8304bf306ceff5b1b 100644 (file)
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -87,6 +87,11 @@ static int add_swap(
         assert(what);
         assert(me);
 
+        if (access("/proc/swaps", F_OK) < 0) {
+                log_info("Swap not supported, ignoring fstab swap entry for %s.", what);
+                return 0;
+        }
+
         if (detect_container(NULL) > 0) {
                 log_info("Running in a container, ignoring fstab swap entry for %s.", what);
                 return 0;
@@ -355,7 +360,7 @@ static int parse_fstab(bool initrd) {
                 if (!what)
                         return log_oom();
 
-                if (detect_container(NULL) > 0 && is_device_path(what)) {
+                if (is_device_path(what) && path_is_read_only_fs("sys") > 0) {
                         log_info("Running in a container, ignoring fstab device entry for %s.", what);
                         continue;
                 }