From owner-freebsd-hackers@FreeBSD.ORG Sun Feb 8 12:11:47 2009 Return-Path: Delivered-To: hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 450E51065673; Sun, 8 Feb 2009 12:11:47 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from mail.terabit.net.ua (mail.terabit.net.ua [195.137.202.147]) by mx1.freebsd.org (Postfix) with ESMTP id E010D8FC08; Sun, 8 Feb 2009 12:11:46 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from skuns.zoral.com.ua ([91.193.166.194] helo=mail.zoral.com.ua) by mail.terabit.net.ua with esmtps (TLSv1:AES256-SHA:256) (Exim 4.63 (FreeBSD)) (envelope-from ) id 1LW8Vl-0002ZX-LK; Sun, 08 Feb 2009 14:11:45 +0200 Received: from deviant.kiev.zoral.com.ua (root@deviant.kiev.zoral.com.ua [10.1.1.148]) by mail.zoral.com.ua (8.14.2/8.14.2) with ESMTP id n18CBgmi048792 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 8 Feb 2009 14:11:43 +0200 (EET) (envelope-from kostikbel@gmail.com) Received: from deviant.kiev.zoral.com.ua (kostik@localhost [127.0.0.1]) by deviant.kiev.zoral.com.ua (8.14.3/8.14.3) with ESMTP id n18CBgq9076765; Sun, 8 Feb 2009 14:11:42 +0200 (EET) (envelope-from kostikbel@gmail.com) Received: (from kostik@localhost) by deviant.kiev.zoral.com.ua (8.14.3/8.14.3/Submit) id n18CBgf0076762; Sun, 8 Feb 2009 14:11:42 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: deviant.kiev.zoral.com.ua: kostik set sender to kostikbel@gmail.com using -f Date: Sun, 8 Feb 2009 14:11:42 +0200 From: Kostik Belousov To: stable@freebsd.org, hackers@freebsd.org Message-ID: <20090208121142.GX9427@deviant.kiev.zoral.com.ua> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Zll6mx50Q8J7qlLQ" Content-Disposition: inline User-Agent: Mutt/1.4.2.3i X-Virus-Scanned: ClamAV version 0.94.2, clamav-milter version 0.94.2 on skuns.kiev.zoral.com.ua X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on skuns.kiev.zoral.com.ua X-Virus-Scanned: mail.terabit.net.ua 1LW8Vl-0002ZX-LK 44c56a764e0f31fb4b1e982e561e474f X-Terabit: YES Cc: Subject: Possible VFS KPI and KBI breakage on stable/7 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Feb 2009 12:11:47 -0000 --Zll6mx50Q8J7qlLQ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline There are three sets of changes that would benefit stable/7. Namely, there are 1. Improvements for the UFS unmount or rw->ro remount, that perform suspension during the operation. The changes depend on the the suspension mechanism path, that introduced the suspension owner, and added new VFS OP into the mount method table. This might also fix the hangs with gjournal or gjournal together with snapshots experienced by some users. Since the only real consumer of the suspension is UFS, I believe that MFC would have quite low impact, if any. Corresponding revision is 183073. 2. The openat(2) and similar syscalls. The new ZFS requires openat() functionality. We have to change struct nameidata to merge NDINIT_ATVP(). All modules using namei() need to be recompiled. 3. The Marcus' work on vn_fullpath() support for synthetic filesystems introduces new VOP, vop_vptocnp. This would allow procstat(1) to work on devfs and pseudofs vnodes. As I understand, this would also improve Gnome experience on FreeBSD. All fs modules need to be recompiled. There was one very magisterial voice that objected against KBI breakage on stable branch in principle. In my opinion, the benefits of the bug fixes and functionality improvements with the proposed merges are much greater then inconvenience of the need to recompile out-of-tree fs modules. Changes were discussed with re@ to some extent. In case there is vocal objection against the merge, I would abstain from doing this. --Zll6mx50Q8J7qlLQ Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (FreeBSD) iEYEARECAAYFAkmOy/0ACgkQC3+MBN1Mb4gcogCfSUjXSk3CsUNuDcr1eMvOB96O ER4AoPYtlw+M3VN8c21AxyVG6Vq0ZQck =aEg3 -----END PGP SIGNATURE----- --Zll6mx50Q8J7qlLQ--