From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ross Zwisler Subject: Re: [PATCH] null_blk: fix wrong capacity when bs is not 512 bytes Date: Wed, 2 Sep 2015 12:42:33 -0600 Message-ID: <20150902184233.GB32255@linux.intel.com> References: <1441023451-17049-1-git-send-email-m@bjorling.me> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: axboe@fb.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: Matias =?iso-8859-1?Q?Bj=F8rling?= Return-path: Content-Disposition: inline In-Reply-To: <1441023451-17049-1-git-send-email-m@bjorling.me> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Mon, Aug 31, 2015 at 02:17:31PM +0200, Matias Bj=F8rling wrote: > set_capacity() sets device's capacity using 512 bytes sectors. > null_blk calculates the number of sectors by size / bs, which > set_capacity is called with. This led to null_blk exposing the > wrong number of sectors when bs is not 512 bytes. >=20 > Signed-off-by: Matias Bj=F8rling > --- > drivers/block/null_blk.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) >=20 > diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c > index 6f9b753..bf8f764 100644 > --- a/drivers/block/null_blk.c > +++ b/drivers/block/null_blk.c > @@ -588,8 +588,7 @@ static int null_add_dev(void) > blk_queue_physical_block_size(nullb->q, bs); > =20 > size =3D gb * 1024 * 1024 * 1024ULL; > - sector_div(size, bs); > - set_capacity(disk, size); > + set_capacity(disk, size >> 9); > =20 > disk->flags |=3D GENHD_FL_EXT_DEVT | GENHD_FL_SUPPRESS_PARTITION_IN= =46O; > disk->major =3D null_major; Looks correct. Reviewed-by: Ross Zwisler