block: always use st_dev (device ID) of / when looking for root

Use this method even if UBIFS extroot support is enabled. This is needed
on x86 systems (using F2FS for overlay) as they may still come with F2FS
enabled.

Ref: https://bugs.openwrt.org/index.php?do=details&task_id=2231
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

diff --git a/block.c b/block.c
index fd35d6b650faf7f9a33d0cf477b6b7b905ed5b89..c4ae88ae008e974f21aef6a79340dfc197e0e8fd 100644 (file)
--- a/block.c
+++ b/block.c
@@ -1316,8 +1316,7 @@ static int find_block_ubi_RO(libubi_t libubi, char *name, char *part, int plen)
 
        return err;
 }
-
-#else
+#endif
 
 static int find_root_dev(char *buf, int len)
 {
@@ -1348,8 +1347,6 @@ static int find_root_dev(char *buf, int len)
        return -1;
 }
 
-#endif
-
 static int test_fs_support(const char *name)
 {
        char line[128], *p;
@@ -1392,26 +1389,25 @@ static int check_extroot(char *path)
        char devpath[32];
        char tag[64];
        FILE *fp;
+       int err;
 
+       err = find_block_mtd("\"rootfs\"", devpath, sizeof(devpath));
 #ifdef UBIFS_EXTROOT
-       if (find_block_mtd("\"rootfs\"", devpath, sizeof(devpath))) {
-               int err = -1;
+       if (err) {
                libubi_t libubi;
 
                libubi = libubi_open();
                err = find_block_ubi_RO(libubi, "rootfs", devpath, sizeof(devpath));
                libubi_close(libubi);
-               if (err)
-                       return -1;
-       }
-#else
-       if (find_block_mtd("\"rootfs\"", devpath, sizeof(devpath))) {
-               if (find_root_dev(devpath, sizeof(devpath))) {
-                       ULOG_ERR("extroot: unable to determine root device\n");
-                       return -1;
-               }
        }
 #endif
+       if (err) {
+               err = find_root_dev(devpath, sizeof(devpath));
+       }
+       if (err) {
+               ULOG_ERR("extroot: unable to determine root device\n");
+               return -1;
+       }
 
        /* Find root device probe_info so we know its UUID */
        list_for_each_entry(tmp, &devices, list) {