From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: [PATCH 1/2] md: Add configurability for consistency check feature Date: Tue, 18 Mar 2014 09:54:56 +1100 Message-ID: <20140318095456.53e2b5cf@notabene.brown> References: <1395068405-13860-1-git-send-email-linux-kernel@rmueck.de> <1395068405-13860-2-git-send-email-linux-kernel@rmueck.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/b1/uXr_wRHTdqgWSUIGh+Ba"; protocol="application/pgp-signature" Return-path: In-Reply-To: <1395068405-13860-2-git-send-email-linux-kernel@rmueck.de> Sender: linux-kernel-owner@vger.kernel.org To: Ralph Mueck Cc: i4passt@lists.cs.fau.de, linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, Matthias Oefelein List-Id: linux-raid.ids --Sig_/b1/uXr_wRHTdqgWSUIGh+Ba Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 17 Mar 2014 16:00:04 +0100 Ralph Mueck wro= te: > This patch adds sysfs configurability for the md level-1 RAID > consistency check. > The feature introduces a new attribute in sysfs named "safe_read". > To toggle consistency checks on/off, simply echo safe_read in > /sys/block/md*/md/safe_read. >=20 > Signed-off-by: Ralph Mueck > Signed-off-by: Matthias Oefelein >=20 > --- > drivers/md/md.c | 27 +++++++++++++++++++++++++++ > drivers/md/md.h | 3 +++ > 2 files changed, 30 insertions(+) >=20 > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 4ad5cc4..5cc9a00 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -4652,6 +4652,32 @@ static struct md_sysfs_entry md_array_size =3D > __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show, > array_size_store); > =20 > +static ssize_t > +safe_read_show(struct mddev *mddev, char *page) > +{ > + if(mddev->safe_read) > + return sprintf(page, "enabled\n"); > + else > + return sprintf(page, "disabled\n"); > +} > + > +static ssize_t > +safe_read_store(struct mddev *mddev, const char *buf, size_t len) > +{ > + if(mddev->pers->level !=3D 1) { > + printk(KERN_NOTICE "RAID level not supported!\n"); > + return len; > + } > + if (strncmp(buf, "safe_read", 9) =3D=3D 0) { > + mddev->safe_read =3D !mddev->safe_read; > + } > + return len; > +} > + So let me get this straight.... There is a sysfs file called "safe_read". When you read from that file it reports either "enabled" or "disabled". However you cannot write "enabled" or "disabled" to the file. Rather you write "safe_read". And when you do, it toggles the status. Seriously? Any chance you could use device_show_bool / device_store_bool ?? NeilBrown --Sig_/b1/uXr_wRHTdqgWSUIGh+Ba Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBUyd9QDnsnt1WYoG5AQL3vA/9Fgu7lYGkUxzwvADF7JB8uuQ95ae9yUKJ FlQaNY4ec67ALa2E9z+aeX+qt8Xi7JgPsPnQ4+pb3wqLUscMEq2EpxFaeYlJfOYZ ntBCq+uYdSQZI2MLsFVA7An7sDuQhDatGVArNO41pwLe4l6ry17ChOMtCfmfE0fP D/6f8iL0doCjVcZO5wuvx8iFvlMXENTTNWNiPHpKGi2cBW8YRHZdGzFYVDcSENFD HsX6p0nREXPSPYrN8E9SVHEE9SHmRy5U2ZYzNmkw3SAljjS8WuYecxumJY89Atzo n1vVb8GMMxie0fSKietGv1pEexthg9wSWAEFjDr7AtgBo8XjHGgIUPucxZDkI/Uc fIDMCjB4h1RsEOAVI+sqpWzWWpQcR1PfJbag8N+uobzMpNNRbtZQa+QNlgtxvI6x RyIRJSK87clyAxzQyw3EzzbQnwlGWjIhxaGhjqTFkFCrFIfWILDTzxn3+eQeNg34 UYMPUb3qeH1cts9C9Nrcum776z1cwWFYHV67X23fBbPxcd3WR1VA9jf8hB/mttvt XSQD9K2oFEaOCEPf0jcgRoA6kG1/740pg0yPvBKgGq+BeiVm1wtP0OTMw4b6ePSj 5a6EnbPXNF4yYZnbDwNQdfq7AiDz4a0uJ9dRG0w57OHVzMXdAoAsVubqwfXR5jV7 KPiFME3XJpI= =WXkq -----END PGP SIGNATURE----- --Sig_/b1/uXr_wRHTdqgWSUIGh+Ba--