From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from dude02.hi.pengutronix.de ([2001:67c:670:100:1d::28]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kQs6n-0006J3-5x for ptxdist@pengutronix.de; Fri, 09 Oct 2020 15:06:53 +0200 Received: from mol by dude02.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1kQs6m-0001b0-RF for ptxdist@pengutronix.de; Fri, 09 Oct 2020 15:06:52 +0200 Date: Fri, 9 Oct 2020 15:06:52 +0200 From: Michael Olbrich Message-ID: <20201009130652.GA3084@pengutronix.de> References: <20201007223840.GA876287@lenoch> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201007223840.GA876287@lenoch> Subject: Re: [ptxdist] fake-overlayfs List-Id: PTXdist Development Mailing List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: ptxdist@pengutronix.de Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ptxdist-bounces@pengutronix.de Sender: "ptxdist" To: ptxdist@pengutronix.de Hi, On Thu, Oct 08, 2020 at 12:38:40AM +0200, Ladislav Michl wrote: > fake-overlayfs help text reads: > 'fake an overlay filesystem like unionfs by copying the original > content to a tmpfs.' > > However it does not seem to do so. Bellow is attempt to fix that. > 1) /usr/sbin/fake-overlayfs does not seem to mount tmpfs > 2) with MountFlags=private is tmpfs mount invisible for the rest of system > 3) perhaps use /run only with systemd? So I haven't tested this in a while but what is supposed to happen is this: You add the tmpfs to the fstab for any directory that should be writable. Then fake-overlayfs will fill that tmpfs with the content that is hidden by the tmpfs. Michael > Comments welcome, > ladis > > diff --git a/projectroot/usr/lib/systemd/system/fake-overlayfs.service b/projectroot/usr/lib/systemd/system/fake-overlayfs.service > index daa6fd03f..818d624b9 100644 > --- a/projectroot/usr/lib/systemd/system/fake-overlayfs.service > +++ b/projectroot/usr/lib/systemd/system/fake-overlayfs.service > @@ -1,11 +1,10 @@ > [Unit] > Description=Fake Overlay Filesystem > DefaultDependencies=no > -After=local-fs.target > +Before=local-fs.target > Requires=local-fs.target > > [Service] > Type=oneshot > -RemainAfterExit=no > +RemainAfterExit=yes > ExecStart=/usr/sbin/fake-overlayfs > -MountFlags=private > diff --git a/projectroot/usr/sbin/fake-overlayfs b/projectroot/usr/sbin/fake-overlayfs > index b6692c578..de852b520 100644 > --- a/projectroot/usr/sbin/fake-overlayfs > +++ b/projectroot/usr/sbin/fake-overlayfs > @@ -2,7 +2,7 @@ > > OVERLAY_DIRS="@OVERLAY_DIRLIST@" > > -bdir=/tmp/.fake-overlay-root > +bdir=/run/.fake-overlay-root > > mkdir $bdir > mount -o bind,private / $bdir > @@ -14,10 +14,9 @@ while [ $# -gt 0 ]; do > shift > continue > fi > - echo $1 > src="$bdir$1" > - dst="$1/" > - test -e "$dst" || mkdir $dst > + dst=$1 > + mount -t tmpfs tmpfs $dst > cp -a "$src/"* "$src/".[^.]* "$src/"..?* $dst 2> /dev/null > shift > done > > _______________________________________________ > ptxdist mailing list > ptxdist@pengutronix.de > To unsubscribe, send a mail with subject "unsubscribe" to ptxdist-request@pengutronix.de > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ ptxdist mailing list ptxdist@pengutronix.de To unsubscribe, send a mail with subject "unsubscribe" to ptxdist-request@pengutronix.de