JFS: Add back directory i_size calculations for legacy partitions

Linux-formatted jfs partitions have a different idea about what i_size
represents than partitions formatted on OS/2.  The i_size calculation is
now based on the size of the directory index.  For legacy partitions, which
have no directory index, the i_size is never being updated.

This patch adds back the original i_size calculations for legacy partitions.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>

fs/jfs/jfs_dtree.c

@@ -1005,6 +1005,9 @@ static int dtSplitUp(tid_t tid,
 
 		DT_PUTPAGE(smp);
 
+		if (!DO_INDEX(ip))
+			ip->i_size = xlen << sbi->l2bsize;
+
 		goto freeKeyName;
 	}
 
@@ -1055,7 +1058,9 @@ static int dtSplitUp(tid_t tid,
 				xaddr = addressPXD(pxd) + xlen;
 				dbFree(ip, xaddr, (s64) n);
 			}
-		}
+		} else if (!DO_INDEX(ip))
+			ip->i_size = lengthPXD(pxd) << sbi->l2bsize;
+
 
 	      extendOut:
 		DT_PUTPAGE(smp);
@@ -1098,6 +1103,9 @@ static int dtSplitUp(tid_t tid,
 		goto splitOut;
 	}
 
+	if (!DO_INDEX(ip))
+		ip->i_size += PSIZE;
+
 	/*
 	 * propagate up the router entry for the leaf page just split
 	 *
@@ -2424,6 +2432,9 @@ static int dtDeleteUp(tid_t tid, struct inode *ip,
 		break;
 	}
 
+	if (!DO_INDEX(ip))
+		ip->i_size -= PSIZE;
+
 	return 0;
 }