[GFS2] Shrink gfs2_inode (8) - i_vn

This shrinks the size of the gfs2_inode by 8 bytes by
replacing the version counter with a one bit valid/invalid
flag.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

4 files changed, 7 insertions, 6 deletions

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index aad45b7a927d..9c2033714b08 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -305,8 +305,9 @@ static void inode_go_inval(struct gfs2_glock *gl, int flags)
         int data = (flags & DIO_DATA);
 
         if (meta) {
+                struct gfs2_inode *ip = gl->gl_object;
                 gfs2_meta_inval(gl);
-                gl->gl_vn++;
+                set_bit(GIF_INVALID, &ip->i_flags);
         }
         if (data)
                 gfs2_page_inval(gl);
@@ -351,7 +352,7 @@ static int inode_go_lock(struct gfs2_holder *gh)
         if (!ip)
                 return 0;
 
-        if (ip->i_vn != gl->gl_vn) {
+        if (test_bit(GIF_INVALID, &ip->i_flags)) {
                 error = gfs2_inode_refresh(ip);
                 if (error)
                         return error;
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index c0a8c3b6a852..227a74dc5ec0 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -217,6 +217,7 @@ struct gfs2_alloc {
 };
 
 enum {
+        GIF_INVALID             = 0,
         GIF_QD_LOCKED           = 1,
         GIF_PAGED               = 2,
         GIF_SW_PAGED            = 3,
@@ -228,7 +229,6 @@ struct gfs2_inode {
 
         unsigned long i_flags;          /* GIF_... */
 
-        u64 i_vn;
         struct gfs2_dinode_host i_di; /* To be replaced by ref to block */
 
         struct gfs2_glock *i_gl; /* Move into i_gh? */
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index f6177fc68320..e467780837e6 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -145,7 +145,7 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, struct gfs2_inum_host *i
                 if (unlikely(error))
                         goto fail_put;
 
-                ip->i_vn = ip->i_gl->gl_vn - 1;
+                set_bit(GIF_INVALID, &ip->i_flags);
                 error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
                 if (unlikely(error))
                         goto fail_iopen;
@@ -242,7 +242,7 @@ int gfs2_inode_refresh(struct gfs2_inode *ip)
 
         error = gfs2_dinode_in(ip, dibh->b_data);
         brelse(dibh);
-        ip->i_vn = ip->i_gl->gl_vn;
+        clear_bit(GIF_INVALID, &ip->i_flags);
 
         return error;
 }
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 0e4eade47bf2..b247f25effbf 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -844,7 +844,7 @@ static int gfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
         struct gfs2_holder i_gh;
         int error;
 
-        if (ip->i_vn == ip->i_gl->gl_vn)
+        if (!test_bit(GIF_INVALID, &ip->i_flags))
                 return generic_permission(inode, mask, gfs2_check_acl);
 
         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);