From owner-freebsd-current@FreeBSD.ORG  Wed May 24 22:07:41 2006
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
X-Original-To: current@freebsd.org
Delivered-To: freebsd-current@FreeBSD.ORG
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id A462116A455
	for <current@freebsd.org>; Wed, 24 May 2006 22:07:41 +0000 (UTC)
	(envelope-from jhb@freebsd.org)
Received: from server.baldwin.cx (66-23-211-162.clients.speedfactory.net
	[66.23.211.162])
	by mx1.FreeBSD.org (Postfix) with ESMTP id E277643D45
	for <current@freebsd.org>; Wed, 24 May 2006 22:07:40 +0000 (GMT)
	(envelope-from jhb@freebsd.org)
Received: from [10.0.1.114] (nat-outside.atlanta.corp.yahoo.com
	[63.172.193.57]) (authenticated bits=0)
	by server.baldwin.cx (8.13.4/8.13.4) with ESMTP id k4OM7eqT096179
	for <current@freebsd.org>; Wed, 24 May 2006 18:07:40 -0400 (EDT)
	(envelope-from jhb@freebsd.org)
From: John Baldwin <jhb@freebsd.org>
To: current@freebsd.org
Date: Wed, 24 May 2006 18:07:29 -0400
User-Agent: KMail/1.9.1
MIME-Version: 1.0
Content-Type: text/plain;
  charset="us-ascii"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200605241807.29163.jhb@freebsd.org>
X-Virus-Scanned: ClamAV 0.87.1/1480/Wed May 24 12:45:51 2006 on
	server.baldwin.cx
X-Virus-Status: Clean
X-Spam-Status: No, score=-4.0 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 
	autolearn=ham version=3.1.0
X-Spam-Checker-Version: SpamAssassin 3.1.0 (2005-09-13) on server.baldwin.cx
Cc: 
Subject: [PATCH] Change kqueue_register() to use fget()
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
	<freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
	<mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
	<mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 24 May 2006 22:07:42 -0000

This small patch fixes up a part of kevent to use fget() instead of mangling
the filedesc struct directly.  I haven't had time yet to sit down and test
kevent apps with it so would appreciate it if anyone has some idle cycles to
do that.

--- //depot/vendor/freebsd/src/sys/kern/kern_event.c	2006/04/14 14:33:55
+++ //depot/projects/smpng/sys/kern/kern_event.c	2006/04/25 19:47:56
@@ -754,15 +754,12 @@
 int
 kqueue_register(struct kqueue *kq, struct kevent *kev, struct thread *td, int waitok)
 {
-	struct filedesc *fdp;
 	struct filterops *fops;
 	struct file *fp;
 	struct knote *kn, *tkn;
 	int error, filt, event;
 	int haskqglobal;
-	int fd;
 
-	fdp = NULL;
 	fp = NULL;
 	kn = NULL;
 	error = 0;
@@ -778,22 +775,13 @@
 findkn:
 	if (fops->f_isfd) {
 		KASSERT(td != NULL, ("td is NULL"));
-		fdp = td->td_proc->p_fd;
-		FILEDESC_LOCK(fdp);
-		/* validate descriptor */
-		fd = kev->ident;
-		if (fd < 0 || fd >= fdp->fd_nfiles ||
-		    (fp = fdp->fd_ofiles[fd]) == NULL) {
-			FILEDESC_UNLOCK(fdp);
-			error = EBADF;
+		error = fget(td, kev->ident, &fp);
+		if (error)
 			goto done;
-		}
-		fhold(fp);
 
 		if ((kev->flags & EV_ADD) == EV_ADD && kqueue_expand(kq, fops,
 		    kev->ident, 0) != 0) {
-			/* unlock and try again */
-			FILEDESC_UNLOCK(fdp);
+			/* try again */
 			fdrop(fp, td);
 			fp = NULL;
 			error = kqueue_expand(kq, fops, kev->ident, waitok);
@@ -811,7 +799,6 @@
 			 * they are the same thing.
 			 */
 			if (fp->f_data == kq) {
-				FILEDESC_UNLOCK(fdp);
 				error = EINVAL;
 				goto done_noglobal;
 			}
@@ -819,7 +806,6 @@
 			KQ_GLOBAL_LOCK(&kq_global, haskqglobal);
 		}
 
-		FILEDESC_UNLOCK(fdp);
 		KQ_LOCK(kq);
 		if (kev->ident < kq->kq_knlistsize) {
 			SLIST_FOREACH(kn, &kq->kq_knlist[kev->ident], kn_link)

-- 
John Baldwin