ufs - Adjust the on-disk structure to FreeBSD's

* Adjust the superblock on-disk structure a bit to include a few things
  like a volume name as FreeBSD does.

* NOTE: This introduces no functional changes but will allow to easily
  extract volume names from volumes.

Obtained-from: FreeBSD

diff --git a/sys/vfs/ufs/fs.h b/sys/vfs/ufs/fs.h
index 52ff517..fb357e7 100644 (file)
--- a/sys/vfs/ufs/fs.h
+++ b/sys/vfs/ufs/fs.h
@@ -103,7 +103,13 @@
  * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
  * the super block for this name.
  */
-#define MAXMNTLEN      512
+#define MAXMNTLEN      468
+
+/*
+ * The volume name for this filesystem is maintained in fs_volname.
+ * MAXVOLLEN defines the length of the buffer allocated.
+ */
+#define MAXVOLLEN      32
 
 /*
  * There is a 128-byte region in the superblock reserved for in-core
@@ -252,6 +258,9 @@ struct fs {
        int8_t   fs_ronly;              /* mounted read-only flag */
        int8_t   fs_flags;              /* see FS_ flags below */
        u_char   fs_fsmnt[MAXMNTLEN];   /* name mounted on */
+       u_char   fs_volname[MAXVOLLEN]; /* volume name */
+       u_int64_t fs_swuid;             /* system-wide uid */
+       int32_t  fs_pad;                /* due to alignment of fs_swuid */
 /* these fields retain the current block allocation info */
        int32_t  fs_cgrotor;            /* last cg searched */
        void    *fs_ocsp[NOCSPTRS];     /* padding; was list of fs_cs buffers */