dnotify readv/writev fix for 2.4.21

Marcelo,

This patch didn't make it into 2.4.21. Zou Pengcheng's original patch was whitespace-damaged, so here's a fresh copy against 2.4.21.

Issue DN_MODIFY on writev, and DN_ACCESS on readv, rather than vice versa.

I can provide a testcase if anyone wants one.

----- Forwarded message from Zou Pengcheng <[email protected]> -----

From: Zou Pengcheng <[email protected]>
To: Marcelo Tosatti <[email protected]>
Cc: [email protected]
Subject: [PATCH] dnotify fix for readv/writev (Linux 2.4.20)
Date: Mon, 2 Dec 2002 09:22:43 +0800
Message-Id: <[email protected]>

hi, Marcelo,

this is a patch to fix the dnotify bug of readv/writev.

Orignally DN_MODIFY is issued on readv while DN_ACCESS is issued on writev, which is obviously wrong. This patch fixes such problem.

cheers,
-- Pengcheng Zou

diff -uNr fs/read_write.c.orig fs/read_write.c
...

----- End forwarded message -----

@@ -322,7 +322,7 @@
 	/* VERIFY_WRITE actually means a read, as we write to user space */
 	if ((ret + (type == VERIFY_WRITE)) > 0)
 		dnotify_parent(file->f_dentry,
-			(type == VERIFY_WRITE) ? DN_MODIFY : DN_ACCESS);
+			(type == VERIFY_WRITE) ? DN_ACCESS : DN_MODIFY);
 	return ret;
 }
 

-andy