From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Elder Subject: Re: [PATCH 2/2] rbd: use the correct length for format 2 object names Date: Sat, 15 Jun 2013 12:05:20 -0500 Message-ID: <51BC9ED0.3000503@linaro.org> References: <1371093046-5814-1-git-send-email-josh.durgin@inktank.com> <1371093046-5814-2-git-send-email-josh.durgin@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ie0-f178.google.com ([209.85.223.178]:44466 "EHLO mail-ie0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753741Ab3FORFR (ORCPT ); Sat, 15 Jun 2013 13:05:17 -0400 Received: by mail-ie0-f178.google.com with SMTP id u16so3924429iet.9 for ; Sat, 15 Jun 2013 10:05:17 -0700 (PDT) In-Reply-To: <1371093046-5814-2-git-send-email-josh.durgin@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Josh Durgin Cc: ceph-devel@vger.kernel.org On 06/12/2013 10:10 PM, Josh Durgin wrote: > Format 2 objects use 16 characters for the object name suffix to be > able to express the full 64-bit range of object numbers. Format 1 > images only use 12 characters for this. Using 12-character names for > format 2 caused userspace and kernel rbd clients to read differently > named objects, which made an image written by one client look empty to > the other client. > > Reported-by: Chris Dunlop > Signed-off-by: Josh Durgin Looks good. Reviewed-by: Alex Elder > drivers/block/rbd.c | 6 +++++- > 1 files changed, 5 insertions(+), 1 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index 9f72125..39ee017 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -1028,12 +1028,16 @@ static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset) > char *name; > u64 segment; > int ret; > + char *name_format; > > name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO); > if (!name) > return NULL; > segment = offset >> rbd_dev->header.obj_order; > - ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, "%s.%012llx", > + name_format = "%s.%012llx"; > + if (rbd_dev->image_format == 2) > + name_format = "%s.%016llx"; > + ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, name_format, > rbd_dev->header.object_prefix, segment); > if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) { > pr_err("error formatting segment name for #%llu (%d)\n", >