GIT: unionfs2-2.6.27.y: Unionfs: maintain one-open-file invariant for non-directories

[Erez Zadok]

commit f03d82ebcb867bd857818f135b0c72dfeaf20659
Author: Erez Zadok <ezk at cs.sunysb.edu>
Date:   Wed Apr 23 19:05:40 2008 -0400

    Unionfs: maintain one-open-file invariant for non-directories
    
    Signed-off-by: Erez Zadok <ezk at cs.sunysb.edu>

diff --git a/fs/unionfs/commonfops.c b/fs/unionfs/commonfops.c
index 2706194..82b0eea 100644
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -320,7 +320,9 @@ static int __unionfs_file_revalidate(struct file *file, struct dentry *dentry,
 	 * to refresh things.
 	 */
 	if (d_deleted(dentry) ||
-	    (sbgen <= fgen && dbstart(dentry) == fbstart(file)))
+	    (sbgen <= fgen &&
+	     dbstart(dentry) == fbstart(file) &&
+	     unionfs_lower_file(file)))
 		goto out_may_copyup;
 
 	/* save orig branch ID */
@@ -369,6 +371,8 @@ static int __unionfs_file_revalidate(struct file *file, struct dentry *dentry,
 			unionfs_mntput(sb->s_root,
 				       branch_id_to_idx(sb, orig_brid));
 		}
+		/* regular files have only one open lower file */
+		fbend(file) = fbstart(file);
 	}
 	atomic_set(&UNIONFS_F(file)->generation,
 		   atomic_read(&UNIONFS_I(dentry->d_inode)->generation));
@@ -381,6 +385,9 @@ out_may_copyup:
 		pr_debug("unionfs: do delay copyup of \"%s\"\n",
 			 dentry->d_name.name);
 		err = do_delayed_copyup(file);
+		/* regular files have only one open lower file */
+		if (!err && !S_ISDIR(dentry->d_inode->i_mode))
+			fbend(file) = fbstart(file);
 	}
 
 out: