#include "alloc-util.h"
#include "blockdev-util.h"
#include "chase-symlinks.h"
+#include "device-util.h"
#include "devnum-util.h"
#include "dirent-util.h"
#include "env-util.h"
continue;
/* Check if partition type matches */
- if (rr->partition_type_set && !sd_id128_equal(pinfo.type, rr->partition_type))
+ if (rr->partition_type_set && !sd_id128_equal(pinfo.type, rr->partition_type.uuid))
continue;
/* A label of "_empty" means "not used so far" for us */
assert(rr);
if (rr->path_auto) {
+ struct stat orig_root_stats;
- /* NB: we don't actually check the backing device of the root fs "/", but of "/usr", in order
- * to support environments where the root fs is a tmpfs, and the OS itself placed exclusively
- * in /usr/. */
+ /* NB: If the root mount has been replaced by some form of volatile file system (overlayfs),
+ * the original root block device node is symlinked in /run/systemd/volatile-root. Let's
+ * follow that link here. If that doesn't exist, we check the backing device of "/usr". We
+ * don't actually check the backing device of the root fs "/", in order to support
+ * environments where the root fs is a tmpfs, and the OS itself placed exclusively in
+ * /usr/. */
if (rr->type != RESOURCE_PARTITION)
return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
return log_error_errno(SYNTHETIC_ERRNO(EPERM),
"Block device is not allowed when using --root= mode.");
- r = get_block_device_harder("/usr/", &d);
+ r = stat("/run/systemd/volatile-root", &orig_root_stats);
+ if (r < 0) {
+ if (errno == -ENOENT) /* volatile-root not found */
+ r = get_block_device_harder("/usr/", &d);
+ else
+ return log_error_errno(r, "Failed to stat /run/systemd/volatile-root: %m");
+ } else if (!S_ISBLK(orig_root_stats.st_mode)) /* symlink was present but not block device */
+ return log_error_errno(SYNTHETIC_ERRNO(ENOTBLK), "/run/systemd/volatile-root is not linked to a block device.");
+ else /* symlink was present and a block device */
+ d = orig_root_stats.st_rdev;
} else if (rr->type == RESOURCE_PARTITION) {
- _cleanup_close_ int fd = -1, real_fd = -1;
+ _cleanup_close_ int fd = -EBADF, real_fd = -EBADF;
_cleanup_free_ char *resolved = NULL;
struct stat st;
return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
"File system is not placed on a partition block device, cannot determine whole block device backing root file system.");
- r = device_path_make_canonical(S_IFBLK, d, &p);
+ r = devname_from_devnum(S_IFBLK, d, &p);
if (r < 0)
return r;