From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] virtio_blk: Add help function to format mass of disks Date: Tue, 10 Apr 2012 16:16:10 +0300 Message-ID: <4F84329A.60703@redhat.com> References: <1334042885-8330-1-git-send-email-renmx@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1334042885-8330-1-git-send-email-renmx@cn.fujitsu.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Ren Mingxin Cc: axboe@kernel.dk, kvm@vger.kernel.org, linux-scsi@vger.kernel.org, mst@redhat.com, asamymuthupa@micron.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, James.Bottomley@HansenPartnership.com, tj@kernel.org List-Id: linux-scsi@vger.kernel.org On 04/10/2012 10:28 AM, Ren Mingxin wrote: > The current virtio block's naming algorithm just supports 18278 > (26^3 + 26^2 + 26) disks. If there are mass of virtio blocks, > there will be disks with the same name. > > Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, I add > function "virtblk_name_format()" for virtio block to support mass > of disks naming. > > Signed-off-by: Ren Mingxin > --- > drivers/block/virtio_blk.c | 38 ++++++++++++++++++++++++++------------ > 1 files changed, 26 insertions(+), 12 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index c4a60ba..86516c8 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -374,6 +374,31 @@ static int init_vq(struct virtio_blk *vblk) > return err; > } > > +static int virtblk_name_format(char *prefix, int index, char *buf, int buflen) > +{ > + const int base = 'z' - 'a' + 1; > + char *begin = buf + strlen(prefix); > + char *begin = buf + strlen(prefix); Duplicate line. > + char *end = buf + buflen; > + char *p; > + int unit; > + > + p = end - 1; > + *p = '\0'; > + unit = base; Why not use 'base' below? neither unit nor base change. > + do { > + if (p == begin) > + return -EINVAL; > + *--p = 'a' + (index % unit); > + index = (index / unit) - 1; > + } while (index >= 0); > + > + memmove(begin, p, end - p); > + memcpy(buf, prefix, strlen(prefix)); > + > + return 0; > +} > + > -- error compiling committee.c: too many arguments to function