ocfs2: Free up some space in the lvb

lvb_version doesn't need to be a whole 32 bits. Make it an 8 bit field to
free up some space. This should be backwards compatible until we use one of
the fields, in which case we'd bump the lvb version anyway.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

2 files changed, 6 insertions, 4 deletions

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 764d15defd88..f80fb14ee815 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -1413,7 +1413,7 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
 
         lvb = (struct ocfs2_meta_lvb *) lockres->l_lksb.lvb;
 
-        lvb->lvb_version   = cpu_to_be32(OCFS2_LVB_VERSION);
+        lvb->lvb_version   = OCFS2_LVB_VERSION;
         lvb->lvb_isize     = cpu_to_be64(i_size_read(inode));
         lvb->lvb_iclusters = cpu_to_be32(oi->ip_clusters);
         lvb->lvb_iuid      = cpu_to_be32(inode->i_uid);
@@ -1486,7 +1486,7 @@ static inline int ocfs2_meta_lvb_is_trustable(struct ocfs2_lock_res *lockres)
 {
         struct ocfs2_meta_lvb *lvb = (struct ocfs2_meta_lvb *) lockres->l_lksb.lvb;
 
-        if (be32_to_cpu(lvb->lvb_version) == OCFS2_LVB_VERSION)
+        if (lvb->lvb_version == OCFS2_LVB_VERSION)
                 return 1;
         return 0;
 }
@@ -3167,7 +3167,7 @@ void ocfs2_dump_meta_lvb_info(u64 level,
         mlog(level, "LVB information for %s (called from %s:%u):\n",
              lockres->l_name, function, line);
         mlog(level, "version: %u, clusters: %u\n",
-             be32_to_cpu(lvb->lvb_version), be32_to_cpu(lvb->lvb_iclusters));
+             lvb->lvb_version, be32_to_cpu(lvb->lvb_iclusters));
         mlog(level, "size: %llu, uid %u, gid %u, mode 0x%x\n",
              (unsigned long long)be64_to_cpu(lvb->lvb_isize),
              be32_to_cpu(lvb->lvb_iuid), be32_to_cpu(lvb->lvb_igid),
diff --git a/fs/ocfs2/dlmglue.h b/fs/ocfs2/dlmglue.h
index 340251567e99..3476a1611341 100644
--- a/fs/ocfs2/dlmglue.h
+++ b/fs/ocfs2/dlmglue.h
@@ -32,7 +32,9 @@
 #define OCFS2_LVB_VERSION 3
 
 struct ocfs2_meta_lvb {
-        __be32       lvb_version;
+        __be16       lvb_reserved0;
+        __u8         lvb_reserved1;
+        __u8         lvb_version;
         __be32       lvb_iclusters;
         __be32       lvb_iuid;
         __be32       lvb_igid;