From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH v2 02/26] block: Add bio_advance() Date: Thu, 20 Sep 2012 14:58:27 -0700 Message-ID: <20120920215827.GF7264@google.com> References: <1347322957-25260-1-git-send-email-koverstreet@google.com> <1347322957-25260-3-git-send-email-koverstreet@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1347322957-25260-3-git-send-email-koverstreet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> Sender: linux-bcache-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Kent Overstreet 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, neilb-l3A5Bk7waGM@public.gmane.org List-Id: linux-bcache@vger.kernel.org On Mon, Sep 10, 2012 at 05:22:13PM -0700, Kent Overstreet wrote: > +/** > + * bio_advance - increment/complete a bio by some number of bytes > + * @bio: bio to advance > + * @bytes: number of bytes to complete > + * > + * This updates bi_sector, bi_size and bi_idx; if the number of bytes to > + * complete doesn't align with a bvec boundary, then bv_len and bv_offset will > + * be updated on the last bvec as well. > + * > + * @bio will then represent the remaining, uncompleted portion of the io. > + */ > +void bio_advance(struct bio *bio, unsigned bytes) > +{ > + if (bio_integrity(bio)) > + bio_integrity_advance(bio, bytes); > + > + bio->bi_sector += bytes >> 0; Hmmm.... bytes >> 0? > + bio->bi_size -= bytes; > + > + if (!bio->bi_size) > + return; > + > + while (bytes) { > + if (unlikely(bio->bi_idx >= bio->bi_vcnt)) { > + printk(KERN_ERR "%s: bio idx %d >= vcnt %d\n", pr_err() is preferred but maybe WARN_ON_ONCE() is better fit here? This happening would be a bug, right? Thanks. -- tejun