From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 27 Jan 2005 10:16:55 +0100 From: Lars Marowsky-Bree To: Philipp Reisner , drbd-dev@lists.linbit.com Subject: Re: [Drbd-dev] [patch] __bio_clone() behaviour Message-ID: <20050127091655.GI5511@marowsky-bree.de> References: <20050126164612.GH5511@marowsky-bree.de> <200501270956.16709.philipp.reisner@linbit.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <200501270956.16709.philipp.reisner@linbit.com> Cc: List-Id: Coordination of development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 2005-01-27T09:56:16, Philipp Reisner wrote: > This really gives me the feeling that I should not have done the > 0.7.9 release. --- The only one to blame is myself, who thought it > would be a nice idea to have the same release as SUSE. > Bullshit -> The next release will only happen when I am convinced > that the new release is necessary, and that it will not be a > disaster. Yeah, that's probably a good idea. We're used to releasing patched versions anyway ;-) (The 0.7.9 we had picked up had to have it's version number (and only the version number) patched back to 0.7.5; can't update the version number in a released product, even if the rest of the code is the same. That's political games for you. *sigh*) > BTW, regarind this patch: We now modify someone else's BIO. > Is this a good idea ? Well, quite frankly, it is not entirely a good idea. However, it's as sane as the other stuff drbd does with bios. It doesn't have any other side effect beyond making the __bio_clone() call not misbehave. The bi_max_vecs doesn't have any other uses in that scenario and it's safe, but not sane ;-) I checked with axboe and grepped the kernel source, and it's the best work around we can do right now short of converting drbd to use the "proper" APIs. Jens thinks the __bio_clone() call probably should be unexported; the "real" API (bio_clone()) would have automatically done the right thing, and in fact drbd seems to be the _only_ user of __bio_clone() anywhere. Everyone else goes via bio_alloc(), bio_clone(), bio_get/_put() et cetera. Sincerely, Lars Marowsky-Brée -- High Availability & Clustering SUSE Labs, Research and Development SUSE LINUX Products GmbH - A Novell Business