From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: [PATCH 0/9] Prep work for immutable bio vecs Date: Sun, 9 Sep 2012 18:21:02 -0700 Message-ID: <20120910012101.GB23241@moria.home.lan> References: <1347058760-30794-1-git-send-email-koverstreet@google.com> <20120908194115.GC12773@dhcp-172-17-108-109.mtv.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20120908194115.GC12773-RcKxWJ4Cfj1J2suj2OqeGauc2jM2gXBXkQQo+JxHRPFibQn6LdNjmg@public.gmane.org> Sender: linux-bcache-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tejun Heo Cc: linux-bcache-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org List-Id: linux-bcache@vger.kernel.org On Sat, Sep 08, 2012 at 12:41:15PM -0700, Tejun Heo wrote: > Hello, Kent. > > On Fri, Sep 07, 2012 at 03:59:11PM -0700, Kent Overstreet wrote: > > Random assortment of refactoring and trivial cleanups. > > > > Immutable bio vecs and efficient bio splitting require auditing and removing > > pretty much all bi_idx uses, among other things. > > > > The reason is that with immutable bio vecs we can't use the bvec array > > directly; if we have a partially completed bvec, that'll be indicated with a > > field in struct bvec_iter (which gets embedded in struct bio) - bi_bvec_done. > > > > bio_for_each_segments() will handle this transparently, so code needs to be > > converted to use it or some other generic accessor. > > > > Also, bio splitting means that when a driver gets a bio, bi_idx and > > bi_bvec_done may both be nonzero. Again, just need to use generic accessors. > > There are three pending patchsets and I don't know how they're > supposed to come together. Please explain on which tree the patches > are based and how they stack and preferably provide a git branch. Both of the new ones depend on the block cleanups series, but they shouldn't depend on each other (bar perhaps some trivial merge conflicts in bio.h) Git repo - block_stuff branch on http://evilpiepirate.org/git/linux-bcache.git/