--- linux-2.5.6/fs/reiserfs/inode.c.orig	Tue Mar 12 15:27:44 2002
+++ linux-2.5.6/fs/reiserfs/inode.c	Tue Mar 12 15:27:48 2002
@@ -440,6 +440,24 @@
     return reiserfs_get_block(inode, block, bh_result, GET_BLOCK_NO_HOLE) ;
 }
 
+static int reiserfs_get_block_direct_io (struct inode * inode, sector_t block,
+			struct buffer_head * bh_result, int create) {
+    int ret ;
+
+    ret = reiserfs_get_block(inode, block, bh_result, create) ;
+
+    /* don't allow direct io onto tail pages */
+    if (ret == 0 && buffer_mapped(bh_result) && bh_result->b_blocknr == 0) {
+	/* make sure future calls to the direct io funcs for this offset
+	** in the file fail by unmapping the buffer
+	*/
+	reiserfs_unmap_buffer(bh_result);
+        ret = -EINVAL ;
+    }
+    return ret ;
+}
+
+
 /*
 ** helper function for when reiserfs_get_block is called for a hole
 ** but the file tail is still in a direct item
@@ -2080,11 +2098,20 @@
     return ret ;
 }
 
+static int reiserfs_direct_io(int rw, struct inode *inode, 
+                              struct kiobuf *iobuf, sector_t blocknr,
+			      int blocksize) 
+{
+    return generic_direct_IO(rw, inode, iobuf, blocknr, blocksize,
+                             reiserfs_get_block_direct_io) ;
+}
+
 struct address_space_operations reiserfs_address_space_operations = {
     writepage: reiserfs_writepage,
     readpage: reiserfs_readpage, 
     sync_page: block_sync_page,
     prepare_write: reiserfs_prepare_write,
     commit_write: reiserfs_commit_write,
-    bmap: reiserfs_aop_bmap
+    bmap: reiserfs_aop_bmap,
+    direct_IO: reiserfs_direct_io,
 } ;

.