Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965524Ab2ERRIH (ORCPT ); Fri, 18 May 2012 13:08:07 -0400 Received: from natasha.panasas.com ([67.152.220.90]:59770 "EHLO natasha.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964988Ab2ERRIB (ORCPT ); Fri, 18 May 2012 13:08:01 -0400 Message-ID: <4FB681DC.7000700@panasas.com> Date: Fri, 18 May 2012 20:07:40 +0300 From: Boaz Harrosh User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:8.0) Gecko/20111113 Thunderbird/8.0 MIME-Version: 1.0 To: CC: , , , , , , , Subject: Re: [PATCH 09/13] block: Add an explicit bio flag for bios that own their bvec References: <363875943e9d0e13bee6ed28239280543e6e5055.1337308722.git.koverstreet@google.com> In-Reply-To: <363875943e9d0e13bee6ed28239280543e6e5055.1337308722.git.koverstreet@google.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2273 Lines: 71 On 05/18/2012 05:59 AM, koverstreet@google.com wrote: > From: Kent Overstreet > > This is for the new bio splitting code. When we split a bio, if the > split occured on a bvec boundry we reuse the bvec for the new bio. But > that means bio_free() can't free it, hence the explicit flag. > > Signed-off-by: Kent Overstreet > --- > fs/bio.c | 3 ++- > include/linux/blk_types.h | 1 + > 2 files changed, 3 insertions(+), 1 deletions(-) > > diff --git a/fs/bio.c b/fs/bio.c > index ecc9088..3332800 100644 > --- a/fs/bio.c > +++ b/fs/bio.c > @@ -234,7 +234,7 @@ void bio_free(struct bio *bio, struct bio_set *bs) > { > void *p; > > - if (bio_has_allocated_vec(bio)) > + if (bio_flagged(bio, BIO_HAS_VEC)) > bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio)); > > if (bio_integrity(bio)) > @@ -305,6 +305,7 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs) > goto err_free; > > nr_iovecs = bvec_nr_vecs(idx); > + bio->bi_flags |= 1 << BIO_HAS_VEC; > } > out_set: > bio->bi_flags |= idx << BIO_POOL_OFFSET; > diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h > index bd9a610..10fca21 100644 > --- a/include/linux/blk_types.h > +++ b/include/linux/blk_types.h > @@ -101,6 +101,7 @@ struct bio { > #define BIO_FS_INTEGRITY 9 /* fs owns integrity data, not block layer */ > #define BIO_QUIET 10 /* Make BIO Quiet */ > #define BIO_MAPPED_INTEGRITY 11/* integrity metadata has been remapped */ > +#define BIO_HAS_VEC 12 /* bio_free() should free bvec */ Just an English nit BIO with out any VECs is when bi_max_vecs is zero. Id prefer a name that denotes allocation or ownership. BIO_OWN_VEC or BIO_ALLOC_VEC or BIO_DELETE_VEC And one technical problem. I would prefer to negate this bit. Zero is the default, set on the exception. Safer and also more logical. BIO_NO_DELETE_VEC > #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) > > /* Thanks Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/