Create initrd-root-device.target synchronization point (#3239)

Add a synchronization point so that custom initramfs units can run
after the root device becomes available, before it is fsck'd and
mounted.

This is useful for custom initramfs units that may modify the
root disk partition table, where the root device is not known in
advance (it's dynamically selected by the generators).

1 files changed, 8 insertions, 0 deletions

diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 343e3b1817..108522873e 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -489,6 +489,7 @@ static int parse_fstab(bool initrd) {
 static int add_sysroot_mount(void) {
         _cleanup_free_ char *what = NULL;
         const char *opts;
+        int r;
 
         if (isempty(arg_root_what)) {
                 log_debug("Could not find a root= entry on the kernel command line.");
@@ -508,6 +509,13 @@ static int add_sysroot_mount(void) {
                 opts = arg_root_options;
 
         log_debug("Found entry what=%s where=/sysroot type=%s", what, strna(arg_root_fstype));
+
+        if (is_device_path(what)) {
+                r = generator_write_initrd_root_device_deps(arg_dest, what);
+                if (r < 0)
+                        return r;
+        }
+
         return add_mount(what,
                          "/sysroot",
                          arg_root_fstype,