diff -urNp 2.4.19rc1/include/linux/fs.h odirect/include/linux/fs.h
--- 2.4.19rc1/include/linux/fs.h	Tue Jun 25 23:56:21 2002
+++ odirect/include/linux/fs.h	Wed Jun 26 17:42:48 2002
@@ -1434,6 +1434,7 @@ extern int generic_file_mmap(struct file
 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
 extern ssize_t generic_file_read(struct file *, char *, size_t, loff_t *);
 extern ssize_t generic_file_write(struct file *, const char *, size_t, loff_t *);
+extern ssize_t do_generic_file_write(struct file *, const char *, size_t, loff_t *);
 extern void do_generic_file_read(struct file *, loff_t *, read_descriptor_t *, read_actor_t);
 extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
diff -urNp 2.4.19rc1/mm/filemap.c odirect/mm/filemap.c
--- 2.4.19rc1/mm/filemap.c	Tue Jun 25 23:56:23 2002
+++ odirect/mm/filemap.c	Wed Jun 26 17:42:50 2002
@@ -1534,6 +1534,7 @@ static ssize_t generic_file_direct_IO(in
 	struct kiobuf * iobuf;
 	struct address_space * mapping = filp->f_dentry->d_inode->i_mapping;
 	struct inode * inode = mapping->host;
+	loff_t	size = inode->i_size;
 
 	new_iobuf = 0;
 	iobuf = filp->f_iobuf;
@@ -1559,6 +1560,9 @@ static ssize_t generic_file_direct_IO(in
 	if (!mapping->a_ops->direct_IO)
 		goto out_free;
 
+	if ((rw == READ) && (offset + count > size))
+		count = size - offset;
+
 	/*
 	 * Flush to disk exclusively the _data_, metadata must remain
 	 * completly asynchronous or performance will go to /dev/null.
@@ -1589,6 +1593,7 @@ static ssize_t generic_file_direct_IO(in
 		if (retval >= 0) {
 			count -= retval;
 			buf += retval;
+			/* warning: weird semantics here, we're reporting a read behind the end of the file */
 			progress += retval;
 		}
 
@@ -1678,8 +1683,6 @@ ssize_t generic_file_read(struct file * 
 			goto out; /* skip atime */
 		size = inode->i_size;
 		if (pos < size) {
-			if (pos + count > size)
-				count = size - pos;
 			retval = generic_file_direct_IO(READ, filp, buf, count, pos);
 			if (retval > 0)
 				*ppos = pos + retval;
@@ -2914,7 +2917,7 @@ inline void remove_suid(struct inode *in
  *							okir@monad.swb.de
  */
 ssize_t
-generic_file_write(struct file *file,const char *buf,size_t count, loff_t *ppos)
+do_generic_file_write(struct file *file,const char *buf,size_t count, loff_t *ppos)
 {
 	struct address_space *mapping = file->f_dentry->d_inode->i_mapping;
 	struct inode	*inode = mapping->host;
@@ -2926,16 +2929,8 @@ generic_file_write(struct file *file,con
 	int		err;
 	unsigned	bytes;
 
-	if ((ssize_t) count < 0)
-		return -EINVAL;
-
-	if (!access_ok(VERIFY_READ, buf, count))
-		return -EFAULT;
-
 	cached_page = NULL;
 
-	down(&inode->i_sem);
-
 	pos = *ppos;
 	err = -EINVAL;
 	if (pos < 0)
@@ -3114,7 +3109,6 @@ out_status:	
 	err = written ? written : status;
 out:
 
-	up(&inode->i_sem);
 	return err;
 fail_write:
 	status = -EFAULT;
@@ -3141,7 +3135,6 @@ o_direct:
 			mark_inode_dirty(inode);
 		}
 		*ppos = end;
-		invalidate_inode_pages2(mapping);
 	}
 	/*
 	 * Sync the fs metadata but not the minor inode changes and
@@ -3152,6 +3145,30 @@ o_direct:
 	goto out_status;
 }
 
+EXPORT_SYMBOL(do_generic_file_write);
+
+ssize_t
+generic_file_write(struct file *file,const char *buf,size_t count, loff_t *ppos)
+{
+	struct inode	*inode = file->f_dentry->d_inode->i_mapping->host;
+	int		err;
+
+	if ((ssize_t) count < 0)
+		return -EINVAL;
+
+	if (!access_ok(VERIFY_READ, buf, count))
+		return -EFAULT;
+
+	down(&inode->i_sem);
+	err = do_generic_file_write(file, buf, count, ppos);
+
+	if ((err > 0) && (file->f_flags & O_DIRECT))
+		invalidate_inode_pages2(file->f_dentry->d_inode->i_mapping);
+	up(&inode->i_sem);
+
+	return err;
+}
+
 void __init page_cache_init(unsigned long mempages)
 {
 	unsigned long htable_size, order;