GIT: unionfs2-2.6.27.y: cleanup: rewrite do_delayed_copyup more cleanly and clearly

[Erez Zadok]

commit 190562398637390774b06dad603ac787d4c21657
Author: Erez Zadok <ezk at bigvaio.(none)>
Date:   Fri May 18 03:07:37 2007 -0400

    cleanup: rewrite do_delayed_copyup more cleanly and clearly

diff --git a/fs/unionfs/commonfops.c b/fs/unionfs/commonfops.c
index 62e9923..2b2aff8 100644
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -257,21 +257,22 @@ out:
 }
 
 /* perform a delayed copyup of a read-write file on a read-only branch */
-static int do_delayed_copyup(struct file *file, struct dentry *dentry)
+static int do_delayed_copyup(struct file *file)
 {
 	int bindex, bstart, bend, err = 0;
+	struct dentry *dentry = file->f_dentry;
 	struct inode *parent_inode = dentry->d_parent->d_inode;
-	loff_t inode_size = file->f_dentry->d_inode->i_size;
+	loff_t inode_size = dentry->d_inode->i_size;
 
 	bstart = fbstart(file);
 	bend = fbend(file);
 
-	BUG_ON(!S_ISREG(file->f_dentry->d_inode->i_mode));
+	BUG_ON(!S_ISREG(dentry->d_inode->i_mode));
 
 	unionfs_check_file(file);
 	unionfs_check_dentry(dentry);
 	for (bindex = bstart - 1; bindex >= 0; bindex--) {
-		if (!d_deleted(file->f_dentry))
+		if (!d_deleted(dentry))
 			err = copyup_file(parent_inode, file, bstart,
 					  bindex, inode_size);
 		else
@@ -281,33 +282,36 @@ static int do_delayed_copyup(struct file *file, struct dentry *dentry)
 		if (!err)
 			break;
 	}
-	if (!err && (bstart > fbstart(file))) {
-		bend = fbend(file);
-		for (bindex = bstart; bindex <= bend; bindex++) {
-			if (unionfs_lower_file_idx(file, bindex)) {
-				unionfs_read_lock(dentry->d_sb);
-				branchput(dentry->d_sb, bindex);
-				unionfs_read_unlock(dentry->d_sb);
-				fput(unionfs_lower_file_idx(file, bindex));
-				unionfs_set_lower_file_idx(file, bindex, NULL);
-			}
-			if (unionfs_lower_mnt_idx(dentry, bindex)) {
-				unionfs_mntput(dentry, bindex);
-				unionfs_set_lower_mnt_idx(dentry, bindex, NULL);
-			}
-			if (unionfs_lower_dentry_idx(dentry, bindex)) {
-				BUG_ON(!dentry->d_inode);
-				iput(unionfs_lower_inode_idx(dentry->d_inode, bindex));
-				unionfs_set_lower_inode_idx(dentry->d_inode, bindex, NULL);
-				dput(unionfs_lower_dentry_idx(dentry, bindex));
-				unionfs_set_lower_dentry_idx(dentry, bindex, NULL);
-			}
+	if (err || (bstart <= fbstart(file)))
+		goto out;
+	bend = fbend(file);
+	for (bindex = bstart; bindex <= bend; bindex++) {
+		if (unionfs_lower_file_idx(file, bindex)) {
+			unionfs_read_lock(dentry->d_sb);
+			branchput(dentry->d_sb, bindex);
+			unionfs_read_unlock(dentry->d_sb);
+			fput(unionfs_lower_file_idx(file, bindex));
+			unionfs_set_lower_file_idx(file, bindex, NULL);
+		}
+		if (unionfs_lower_mnt_idx(dentry, bindex)) {
+			unionfs_mntput(dentry, bindex);
+			unionfs_set_lower_mnt_idx(dentry, bindex, NULL);
+		}
+		if (unionfs_lower_dentry_idx(dentry, bindex)) {
+			BUG_ON(!dentry->d_inode);
+			iput(unionfs_lower_inode_idx(dentry->d_inode, bindex));
+			unionfs_set_lower_inode_idx(dentry->d_inode, bindex,
+						    NULL);
+			dput(unionfs_lower_dentry_idx(dentry, bindex));
+			unionfs_set_lower_dentry_idx(dentry, bindex, NULL);
 		}
-		/* for reg file, we only open it "once" */
-		fbend(file) = fbstart(file);
-		set_dbend(dentry, dbstart(dentry));
-		ibend(dentry->d_inode) = ibstart(dentry->d_inode);
 	}
+	/* for reg file, we only open it "once" */
+	fbend(file) = fbstart(file);
+	set_dbend(dentry, dbstart(dentry));
+	ibend(dentry->d_inode) = ibstart(dentry->d_inode);
+
+out:
 	unionfs_check_file(file);
 	unionfs_check_dentry(dentry);
 	return err;
@@ -397,7 +401,7 @@ int unionfs_file_revalidate(struct file *file, int willwrite)
 	    is_robranch(dentry)) {
 		printk(KERN_DEBUG "unionfs: Doing delayed copyup of a "
 		       "read-write file on a read-only branch.\n");
-		err = do_delayed_copyup(file, dentry);
+		err = do_delayed_copyup(file);
 	}
 
 out: