Messages in this thread | | | Date | Fri, 18 May 2012 20:07:40 +0300 | From | Boaz Harrosh <> | Subject | Re: [PATCH 09/13] block: Add an explicit bio flag for bios that own their bvec |
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On 05/18/2012 05:59 AM, koverstreet@google.com wrote:
> From: Kent Overstreet <koverstreet@google.com> > > 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 <koverstreet@google.com> > --- > 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
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