From owner-freebsd-fs Sun Feb 27 1:43: 6 2000 Delivered-To: freebsd-fs@freebsd.org Received: from freebsd.dk (freebsd.dk [212.242.42.178]) by hub.freebsd.org (Postfix) with ESMTP id DAB1337B53A; Sun, 27 Feb 2000 01:43:00 -0800 (PST) (envelope-from sos@freebsd.dk) Received: (from sos@localhost) by freebsd.dk (8.9.3/8.9.1) id KAA42060; Sun, 27 Feb 2000 10:42:55 +0100 (CET) (envelope-from sos) From: Soren Schmidt Message-Id: <200002270942.KAA42060@freebsd.dk> Subject: Re: UDF/DVD support In-Reply-To: <38B8D0DE.167EB0E7@elischer.org> from Julian Elischer at "Feb 26, 2000 11:23:10 pm" To: julian@elischer.org (Julian Elischer) Date: Sun, 27 Feb 2000 10:42:55 +0100 (CET) Cc: fs@FreeBSD.ORG, current@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org It seems Julian Elischer wrote: > I have been hired to add UDF/DVD-R support to FreeBSD > I will be spending the next few weeks basically doing research > but would like to hear from anyone who is already working in these > areas. > > This may impact un the following areas: > SCSI subsystem > ATA subsystem > Filesystems > Raw/Block(sic) device interface > Encryption/security stuff. Concentrate on the UDF stuff, all the rest is there, or will be shortly. There has been one individual with a DVD-R SCSI drive on the list already, I think he got it to work. You need to use cdrecord anyways since there is no burnersupport in the SCSI chain. There has also been talks about the UDF filesystem, but I dont think anybody has actually started it yet (I know I have it way down on my TODO list :) ) So, when do we have an UDF filesystem :) -Søren To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Sun Feb 27 1:54:48 2000 Delivered-To: freebsd-fs@freebsd.org Received: from critter.freebsd.dk (critter.freebsd.dk [212.242.40.131]) by hub.freebsd.org (Postfix) with ESMTP id 6714C37B52B; Sun, 27 Feb 2000 01:54:41 -0800 (PST) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost.freebsd.dk [127.0.0.1]) by critter.freebsd.dk (8.9.3/8.9.3) with ESMTP id KAA15386; Sun, 27 Feb 2000 10:54:30 +0100 (CET) (envelope-from phk@critter.freebsd.dk) To: Soren Schmidt Cc: julian@elischer.org (Julian Elischer), fs@FreeBSD.ORG, current@FreeBSD.ORG Subject: Re: UDF/DVD support In-reply-to: Your message of "Sun, 27 Feb 2000 10:42:55 +0100." <200002270942.KAA42060@freebsd.dk> Date: Sun, 27 Feb 2000 10:54:30 +0100 Message-ID: <15384.951645270@critter.freebsd.dk> From: Poul-Henning Kamp Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org In message <200002270942.KAA42060@freebsd.dk>, Soren Schmidt writes: >It seems Julian Elischer wrote: >> I have been hired to add UDF/DVD-R support to FreeBSD >> I will be spending the next few weeks basically doing research >> but would like to hear from anyone who is already working in these >> areas. >> >> This may impact un the following areas: >> SCSI subsystem >> ATA subsystem >> Filesystems >> Raw/Block(sic) device interface >> Encryption/security stuff. > >Concentrate on the UDF stuff, all the rest is there, or will be shortly. Yes I agree, and please put the UDF filesystem under sys/fs/udf, we're trying to get a bit more clean top-level /sys -- Poul-Henning Kamp FreeBSD coreteam member phk@FreeBSD.ORG "Real hackers run -current on their laptop." FreeBSD -- It will take a long time before progress goes too far! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Mon Feb 28 2:50: 4 2000 Delivered-To: freebsd-fs@freebsd.org Received: from over.ru (over.rinet.ru [195.54.192.99]) by hub.freebsd.org (Postfix) with SMTP id E7DDB37B755 for ; Mon, 28 Feb 2000 02:50:00 -0800 (PST) (envelope-from tarkhil@over.ru) Received: (qmail 66559 invoked by uid 1000); 28 Feb 2000 10:50:10 -0000 Date: Mon, 28 Feb 2000 13:50:10 +0300 From: Alex Povolotsky To: fs@freebsd.org Subject: Advanced file systems for BSD Message-ID: <20000228135010.A65445@over.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Hello! Are there any work on advanced file systems like XFS or X-FFS for FreeBSD? I have time and hardware to join effort on more efficient FS'es. Alex. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Mon Feb 28 9:32:34 2000 Delivered-To: freebsd-fs@freebsd.org Received: from mail-relay.eunet.no (mail-relay.eunet.no [193.71.71.242]) by hub.freebsd.org (Postfix) with ESMTP id 25DBE37B8D0 for ; Mon, 28 Feb 2000 09:32:31 -0800 (PST) (envelope-from mbendiks@eunet.no) Received: from login-1.eunet.no (login-1.eunet.no [193.75.110.2]) by mail-relay.eunet.no (8.9.3/8.9.3/GN) with ESMTP id SAA30847; Mon, 28 Feb 2000 18:32:28 +0100 (CET) (envelope-from mbendiks@eunet.no) Received: from localhost (mbendiks@localhost) by login-1.eunet.no (8.9.3/8.8.8) with ESMTP id SAA73440; Mon, 28 Feb 2000 18:32:28 +0100 (CET) (envelope-from mbendiks@eunet.no) X-Authentication-Warning: login-1.eunet.no: mbendiks owned process doing -bs Date: Mon, 28 Feb 2000 18:32:28 +0100 (CET) From: Marius Bendiksen To: Alex Povolotsky Cc: fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD In-Reply-To: <20000228135010.A65445@over.ru> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > Are there any work on advanced file systems like XFS or X-FFS for FreeBSD? I > have time and hardware to join effort on more efficient FS'es. Work is being made on an advanced file system for FreeBSD. For more information, contact me privately, as I do not particularly relish posting information on a project before there is actual code available. Marius To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Mon Feb 28 9:37:35 2000 Delivered-To: freebsd-fs@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id 54F5537B594 for ; Mon, 28 Feb 2000 09:37:34 -0800 (PST) (envelope-from bright@fw.wintelcom.net) Received: (from bright@localhost) by fw.wintelcom.net (8.9.3/8.9.3) id KAA04993; Mon, 28 Feb 2000 10:07:37 -0800 (PST) Date: Mon, 28 Feb 2000 10:07:37 -0800 From: Alfred Perlstein To: Alex Povolotsky Cc: fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD Message-ID: <20000228100737.Q21720@fw.wintelcom.net> References: <20000228135010.A65445@over.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: <20000228135010.A65445@over.ru>; from tarkhil@over.ru on Mon, Feb 28, 2000 at 01:50:10PM +0300 Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org * Alex Povolotsky [000228 03:20] wrote: > Hello! > > Are there any work on advanced file systems like XFS or X-FFS for FreeBSD? I > have time and hardware to join effort on more efficient FS'es. Have you read anything on the recent improvements and what's planned with FFS? -Alfred To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Mon Feb 28 20:46:44 2000 Delivered-To: freebsd-fs@freebsd.org Received: from mail.webmonster.de (datasink.webmonster.de [194.162.162.209]) by hub.freebsd.org (Postfix) with SMTP id 1BF0337B9C8 for ; Mon, 28 Feb 2000 20:46:41 -0800 (PST) (envelope-from karsten@rohrbach.de) Received: (qmail 19102 invoked by uid 1000); 29 Feb 2000 04:46:39 -0000 Date: Tue, 29 Feb 2000 05:46:39 +0100 From: "Karsten W. Rohrbach" To: Alfred Perlstein Cc: Alex Povolotsky , fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD Message-ID: <20000229054639.E18770@rohrbach.de> Reply-To: karsten@rohrbach.de References: <20000228135010.A65445@over.ru> <20000228100737.Q21720@fw.wintelcom.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <20000228100737.Q21720@fw.wintelcom.net>; from bright@wintelcom.net on Mon, Feb 28, 2000 at 10:07:37AM -0800 X-Arbitrary-Number-Of-The-Day: 42 X-Sender: karsten@rohrbach.de Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org how about a lfs kinda thing like a port of reiserfs? got it running on one linux box here and it rocks (journaling, resizing,...) /k Alfred Perlstein(bright@wintelcom.net)@Mon, Feb 28, 2000 at 10:07:37AM -0800: > * Alex Povolotsky [000228 03:20] wrote: > > Hello! > > > > Are there any work on advanced file systems like XFS or X-FFS for FreeBSD? I > > have time and hardware to join effort on more efficient FS'es. > > Have you read anything on the recent improvements and what's planned > with FFS? > > -Alfred > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-fs" in the body of the message -- > A truly wise man never plays leapfrog with a unicorn. http://www.webmonster.de http://www.apache.de http://www.splatterworld.de (NIC-HDL KR433/KR11-RIPE) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Tue Feb 29 4:36:58 2000 Delivered-To: freebsd-fs@freebsd.org Received: from mail-relay.eunet.no (mail-relay.eunet.no [193.71.71.242]) by hub.freebsd.org (Postfix) with ESMTP id DC89237BB08 for ; Tue, 29 Feb 2000 04:36:54 -0800 (PST) (envelope-from mbendiks@eunet.no) Received: from login-1.eunet.no (login-1.eunet.no [193.75.110.2]) by mail-relay.eunet.no (8.9.3/8.9.3/GN) with ESMTP id NAA76133; Tue, 29 Feb 2000 13:36:49 +0100 (CET) (envelope-from mbendiks@eunet.no) Received: from localhost (mbendiks@localhost) by login-1.eunet.no (8.9.3/8.8.8) with ESMTP id NAA86931; Tue, 29 Feb 2000 13:36:49 +0100 (CET) (envelope-from mbendiks@eunet.no) X-Authentication-Warning: login-1.eunet.no: mbendiks owned process doing -bs Date: Tue, 29 Feb 2000 13:36:49 +0100 (CET) From: Marius Bendiksen To: "Karsten W. Rohrbach" Cc: Alfred Perlstein , Alex Povolotsky , fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD In-Reply-To: <20000229054639.E18770@rohrbach.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > how about a lfs kinda thing like a port of reiserfs? > got it running on one linux box here and it rocks (journaling, > resizing,...) Excuse me, but what does LFS have to do with Reiser FS ? LFS is the Berkeley Log Structured File System, which utilizes an append-only log to write optimally, whereas Reiser FS is a file system researched and developed by Hans Reiser to store small files in a byte aligned, rather than block aligned, balanced tree. Also, Reiser FS is (according to my local RedHat evangelist) not truly stable enough for production use. Marius To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Tue Feb 29 10:42: 3 2000 Delivered-To: freebsd-fs@freebsd.org Received: from mail.webmonster.de (datasink.webmonster.de [194.162.162.209]) by hub.freebsd.org (Postfix) with SMTP id 3C05B37BC6C for ; Tue, 29 Feb 2000 10:41:54 -0800 (PST) (envelope-from karsten@rohrbach.de) Received: (qmail 42566 invoked by uid 1000); 29 Feb 2000 18:41:52 -0000 Date: Tue, 29 Feb 2000 19:41:52 +0100 From: "Karsten W. Rohrbach" To: Marius Bendiksen Cc: Alfred Perlstein , Alex Povolotsky , fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD Message-ID: <20000229194152.D42254@rohrbach.de> Reply-To: karsten@rohrbach.de References: <20000229054639.E18770@rohrbach.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: ; from mbendiks@eunet.no on Tue, Feb 29, 2000 at 01:36:49PM +0100 X-Arbitrary-Number-Of-The-Day: 42 X-Sender: karsten@rohrbach.de Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org the abbrviation lfs was a general reference to log structured filesystems, which reiserfs as of the last versions also is when it comes to journaling. sorry for mixing up the terminology. /k Marius Bendiksen(mbendiks@eunet.no)@Tue, Feb 29, 2000 at 01:36:49PM +0100: > > how about a lfs kinda thing like a port of reiserfs? > > got it running on one linux box here and it rocks (journaling, > > resizing,...) > > Excuse me, but what does LFS have to do with Reiser FS ? > LFS is the Berkeley Log Structured File System, which utilizes an > append-only log to write optimally, whereas Reiser FS is a file system > researched and developed by Hans Reiser to store small files in a byte > aligned, rather than block aligned, balanced tree. > > Also, Reiser FS is (according to my local RedHat evangelist) not truly > stable enough for production use. > > Marius > -- > Coders do it with a routine. http://www.webmonster.de http://www.apache.de http://www.splatterworld.de (NIC-HDL KR433/KR11-RIPE) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Tue Feb 29 12:38:22 2000 Delivered-To: freebsd-fs@freebsd.org Received: from mail-relay.eunet.no (mail-relay.eunet.no [193.71.71.242]) by hub.freebsd.org (Postfix) with ESMTP id 8441A37BE16 for ; Tue, 29 Feb 2000 12:38:18 -0800 (PST) (envelope-from mbendiks@eunet.no) Received: from login-1.eunet.no (login-1.eunet.no [193.75.110.2]) by mail-relay.eunet.no (8.9.3/8.9.3/GN) with ESMTP id VAA63091; Tue, 29 Feb 2000 21:38:13 +0100 (CET) (envelope-from mbendiks@eunet.no) Received: from localhost (mbendiks@localhost) by login-1.eunet.no (8.9.3/8.8.8) with ESMTP id VAA92831; Tue, 29 Feb 2000 21:38:13 +0100 (CET) (envelope-from mbendiks@eunet.no) X-Authentication-Warning: login-1.eunet.no: mbendiks owned process doing -bs Date: Tue, 29 Feb 2000 21:38:12 +0100 (CET) From: Marius Bendiksen To: "Karsten W. Rohrbach" Cc: Alfred Perlstein , Alex Povolotsky , fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD In-Reply-To: <20000229194152.D42254@rohrbach.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > the abbrviation lfs was a general reference to log structured > filesystems, which reiserfs as of the last versions also is when it > comes to journaling. Er. As I recall, Reiser FS uses preserve lists, which basically means that it writes slightly out of place and bottom-up, which gives you the advantages of journalling without losing quite that much performance. > sorry for mixing up the terminology. No problem. Marius To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Tue Feb 29 12:50:14 2000 Delivered-To: freebsd-fs@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id EB95C37B824 for ; Tue, 29 Feb 2000 12:50:12 -0800 (PST) (envelope-from bright@fw.wintelcom.net) Received: (from bright@localhost) by fw.wintelcom.net (8.9.3/8.9.3) id NAA12832; Tue, 29 Feb 2000 13:20:05 -0800 (PST) Date: Tue, 29 Feb 2000 13:20:04 -0800 From: Alfred Perlstein To: Marius Bendiksen Cc: "Karsten W. Rohrbach" , Alex Povolotsky , fs@FreeBSD.ORG Subject: Re: Advanced file systems for BSD Message-ID: <20000229132004.G21720@fw.wintelcom.net> References: <20000229194152.D42254@rohrbach.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: ; from mbendiks@eunet.no on Tue, Feb 29, 2000 at 09:38:12PM +0100 Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org * Marius Bendiksen [000229 13:08] wrote: > > the abbrviation lfs was a general reference to log structured > > filesystems, which reiserfs as of the last versions also is when it > > comes to journaling. > > Er. As I recall, Reiser FS uses preserve lists, which basically means that > it writes slightly out of place and bottom-up, which gives you the > advantages of journalling without losing quite that much performance. Since no one seems to read it: http://devlinux.com/projects/reiserfs/8_1.html Preserve lists substantially hamper performance for files in the 1-10k size range. We are re-evaluating them. Reiser is supposed to address small files with the most efficiency, considering it's only 32bit you'd expect it to, however this seems to not be the case. -Alfred To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message From owner-freebsd-fs Sat Mar 4 15:40:36 2000 Delivered-To: freebsd-fs@freebsd.org Received: from knecht.Sendmail.ORG (knecht.sendmail.org [209.31.233.176]) by hub.freebsd.org (Postfix) with ESMTP id AB09437B8D6; Sat, 4 Mar 2000 15:40:32 -0800 (PST) (envelope-from mckusick@flamingo.McKusick.COM) Received: from flamingo.McKusick.COM (root@flamingo.mckusick.com [209.31.233.178]) by knecht.Sendmail.ORG (8.10.0.Beta10/8.10.0.Beta10) with ESMTP id e24NeLJ33231; Sat, 4 Mar 2000 15:40:21 -0800 (PST) Received: from flamingo.McKusick.COM (mckusick@localhost [127.0.0.1]) by flamingo.McKusick.COM (8.9.3/8.9.0) with ESMTP id LAA16343; Sat, 4 Mar 2000 11:34:00 -0800 (PST) Message-Id: <200003041934.LAA16343@flamingo.McKusick.COM> To: Alfred Perlstein Subject: Re: changing mount options still can cause damage? Cc: Terry Lambert , fs@freebsd.org, jkh@freebsd.org, Bruce Evans In-reply-to: Your message of "Tue, 22 Feb 2000 20:46:11 PST." <20000222204610.I21720@fw.wintelcom.net> Date: Sat, 04 Mar 2000 11:34:00 -0800 From: Kirk McKusick Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org OK, I have finally had a chance to investigate these issues at greater length and have come to the following conclusions: 1) As suggested below, it would be useful to ffs_flushfiles (or softdep_flushfiles as appropriate) when changing from async -> noasync/sync so that upon return from the mount command the user knows that the filesystem is safe. 2) In reviewing my bug logs for FFS I have found the `corruption' case to which I believe the bug entry in the manual page was alluding. It is possible to get lost inodes in a filesystem that has been downgraded to read-only even if it never ran in async mode. The senario causing trouble goes as follows: A) a process opens a file for reading. B) the file is unlinked C) the filesystem is downgraded to read-only D) the process referencing the now unlinked file exits or closes the file. In this case, the the inode cannot be freed as the filesystem is now in read-only mode. Corruption of this sort is not particularly threatening as the lost inodes will be cleaned up the next time `fsck -p' is run, but the resulting loss of space may be annoying if the filesystem is nearly full. The alternative is to vgone files with link counts of zero when doing a (forcible) downgrade just as we do with files that are open for writing. This would result in the inode being released and the process seeing a dead file (again just as it would for a file open for writing). This seems a slightly odd semantic for a file open for reading, so I have not done it. Does anyone have any views on whether the filesystem should be changed in this way on forcible downgrades? Kirk =-=-=-=-=-=-=-= Date: Tue, 22 Feb 2000 20:46:11 -0800 From: Alfred Perlstein To: Kirk McKusick Cc: Terry Lambert , fs@freebsd.org, jkh@freebsd.org Subject: Re: changing mount options still can cause damage? * Kirk McKusick [000222 19:14] wrote: > A downgrade from read-write to read-only does a complete flush > of the filesystem before setting the clean bit in the superblock. > So, even if you have been running async before or even during > the period that you do the downgrade to read-only, you will > not trash the filesystem. I do not believe that you are lying > to anybody by deleting the commentary about cycling between > read-only and read-write. Appropriate warnings about async are > called for, however the only warning necessary about cycling > between sync and async is that the danger of async does not > go away for several minutes after you have cycled to sync. > > ~Kirk You're saying the exact opposite of what Bruce and Luoqi said, they both say that updating the mount from async -> noasync/sync is safe because of the flush_files call. Looking at the code you seem right... ("ffs/ffs_vfsops.c" line 186 of 1283) if (mp->mnt_flag & MNT_UPDATE) { ump = VFSTOUFS(mp); fs = ump->um_fs; devvp = ump->um_devvp; err = 0; ronly = fs->fs_ronly; /* MNT_RELOAD might change this */ if (ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) { flags = WRITECLOSE; if (mp->mnt_flag & MNT_FORCE) flags |= FORCECLOSE; if (mp->mnt_flag & MNT_SOFTDEP) { err = softdep_flushfiles(mp, flags, p); } else { err = ffs_flushfiles(mp, flags, p); } ronly = 1; } It sure looks like it forces the structures to disk because ffs_flushfiles calls VOP_FSYNC on the filesystem dev vp. Which I would assume fixes up link counts for inodes possibly opened, but deleted before the the filesystem is set to read-only. ufs_close calls ufs_itimes which avoids attempting to update the inode access time if the fs is readonly, so does ufs_inactive. However the async -> noasync/sync doesn't do the same (fsync the device vp), shouldn't it, and if it did, wouldn't that fix the problem? It's not like doing a fsync on the whole filesystem at that point would be a common occurance. I think you're correct however I'm assuming you've seen the case brought up by Bruce and Luoqi, specifically the unlink and downgrade to read-only. thanks, -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] =-=-=-=-=-=-=-=-= Date: Fri, 25 Feb 2000 00:57:42 +1100 (EST) From: Bruce Evans To: Alfred Perlstein cc: Kirk McKusick , Terry Lambert , fs@FreeBSD.ORG, jkh@FreeBSD.ORG Subject: Re: changing mount options still can cause damage? On Tue, 22 Feb 2000, Alfred Perlstein wrote: > * Kirk McKusick [000222 19:14] wrote: > > ... Appropriate warnings about async are > > called for, however the only warning necessary about cycling > > between sync and async is that the danger of async does not > > go away for several minutes after you have cycled to sync. > > > > ~Kirk > > You're saying the exact opposite of what Bruce and Luoqi said, > they both say that updating the mount from async -> noasync/sync > is safe because of the flush_files call. > > Looking at the code you seem right... > However the async -> noasync/sync doesn't do the same (fsync the > device vp), shouldn't it, and if it did, wouldn't that fix the > problem? It's not like doing a fsync on the whole filesystem > at that point would be a common occurance. Copying the code in sync() and changing MNT_NOWAIT to MNT_WAIT in it should work, modulo locking problems. This applies to both async -> noasync and nosync -> sync. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message