cleanup: rewrite do_delayed_copyup more cleanly and clearly

diff --git a/fs/unionfs/commonfops.c b/fs/unionfs/commonfops.c
index 62e992309bb0004f7babc85c9196c4a712d150d2..2b2aff8ea6cc5726985b186f0fc8b625d35bdb7e 100644 (file)
--- a/fs/unionfs/commonfops.c
+++ b/fs/unionfs/commonfops.c
@@ -257,21 +257,22 @@ static int open_highest_file(struct file *file, int willwrite)
 }
 
 /* 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: