cmd/earlyinit: mount pseudo-filesystems

The proposal for merging both init programs was unanimously accepted, so this is set up here alongside devtmpfs.

Signed-off-by: Ophestra <cat@gensokyo.uk>

1 files changed, 36 insertions, 0 deletions

diff --git a/cmd/earlyinit/main.go b/cmd/earlyinit/main.go
index 6dc08035..40883302 100644
--- a/cmd/earlyinit/main.go
+++ b/cmd/earlyinit/main.go
@@ -72,4 +72,40 @@ func main() {
 		}
 	}
 
+	// staying in rootfs, these are no longer used
+	must(os.Remove("/root"))
+	must(os.Remove("/init"))
+
+	must(os.Mkdir("/proc", 0))
+	mustSyscall("mount proc", Mount(
+		"proc",
+		"/proc",
+		"proc",
+		MS_NOSUID|MS_NOEXEC|MS_NODEV,
+		"hidepid=1",
+	))
+
+	must(os.Mkdir("/sys", 0))
+	mustSyscall("mount sysfs", Mount(
+		"sysfs",
+		"/sys",
+		"sysfs",
+		0,
+		"",
+	))
+
+}
+
+// mustSyscall calls [log.Fatalln] if err is non-nil.
+func mustSyscall(action string, err error) {
+	if err != nil {
+		log.Fatalln("cannot "+action+":", err)
+	}
+}
+
+// must calls [log.Fatal] with err if it is non-nil.
+func must(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
 }