From 8fc554552c9d89e7bf76cd4cbc0085648bf3125b Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 9 Jun 2016 10:00:58 -0600 Subject: [PATCH] block: move bvec iterator into include/linux/bvec.h bvec iterator helpers should be used to implement by iterate_bvec():lib/iov_iter.c too, and move them into one header, so that we can keep bvec iterator header out of CONFIG_BLOCK. Then we can remove the reinventing of wheel in iterate_bvec(). Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei Tested-by: Hannes Reinecke Signed-off-by: Jens Axboe --- include/linux/bio.h | 51 +----------------------------------- include/linux/bvec.h | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+), 50 deletions(-) create mode 100644 include/linux/bvec.h diff --git a/include/linux/bio.h b/include/linux/bio.h index 0bbb2e3..8e0f677c 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -31,6 +31,7 @@ /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ #include +#include #define BIO_DEBUG @@ -47,29 +48,6 @@ #define bio_prio(bio) (bio)->bi_ioprio #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio) -/* - * various member access, note that bio_data should of course not be used - * on highmem page vectors - */ -#define __bvec_iter_bvec(bvec, iter) (&(bvec)[(iter).bi_idx]) - -#define bvec_iter_page(bvec, iter) \ - (__bvec_iter_bvec((bvec), (iter))->bv_page) - -#define bvec_iter_len(bvec, iter) \ - min((iter).bi_size, \ - __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done) - -#define bvec_iter_offset(bvec, iter) \ - (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done) - -#define bvec_iter_bvec(bvec, iter) \ -((struct bio_vec) { \ - .bv_page = bvec_iter_page((bvec), (iter)), \ - .bv_len = bvec_iter_len((bvec), (iter)), \ - .bv_offset = bvec_iter_offset((bvec), (iter)), \ -}) - #define bio_iter_iovec(bio, iter) \ bvec_iter_bvec((bio)->bi_io_vec, (iter)) @@ -188,33 +166,6 @@ static inline void *bio_data(struct bio *bio) #define bio_for_each_segment_all(bvl, bio, i) \ for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++) -static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter, - unsigned bytes) -{ - WARN_ONCE(bytes > iter->bi_size, - "Attempted to advance past end of bvec iter\n"); - - while (bytes) { - unsigned len = min(bytes, bvec_iter_len(bv, *iter)); - - bytes -= len; - iter->bi_size -= len; - iter->bi_bvec_done += len; - - if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) { - iter->bi_bvec_done = 0; - iter->bi_idx++; - } - } -} - -#define for_each_bvec(bvl, bio_vec, iter, start) \ - for (iter = (start); \ - (iter).bi_size && \ - ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ - bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len)) - - static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, unsigned bytes) { diff --git a/include/linux/bvec.h b/include/linux/bvec.h new file mode 100644 index 0000000..29c459d --- /dev/null +++ b/include/linux/bvec.h @@ -0,0 +1,74 @@ +/* + * bvec iterator + * + * Copyright (C) 2001 Ming Lei + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public Licens + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- + */ +#ifndef __LINUX_BVEC_ITER_H +#define __LINUX_BVEC_ITER_H + +#include + +/* + * various member access, note that bio_data should of course not be used + * on highmem page vectors + */ +#define __bvec_iter_bvec(bvec, iter) (&(bvec)[(iter).bi_idx]) + +#define bvec_iter_page(bvec, iter) \ + (__bvec_iter_bvec((bvec), (iter))->bv_page) + +#define bvec_iter_len(bvec, iter) \ + min((iter).bi_size, \ + __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done) + +#define bvec_iter_offset(bvec, iter) \ + (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done) + +#define bvec_iter_bvec(bvec, iter) \ +((struct bio_vec) { \ + .bv_page = bvec_iter_page((bvec), (iter)), \ + .bv_len = bvec_iter_len((bvec), (iter)), \ + .bv_offset = bvec_iter_offset((bvec), (iter)), \ +}) + +static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter, + unsigned bytes) +{ + WARN_ONCE(bytes > iter->bi_size, + "Attempted to advance past end of bvec iter\n"); + + while (bytes) { + unsigned len = min(bytes, bvec_iter_len(bv, *iter)); + + bytes -= len; + iter->bi_size -= len; + iter->bi_bvec_done += len; + + if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) { + iter->bi_bvec_done = 0; + iter->bi_idx++; + } + } +} + +#define for_each_bvec(bvl, bio_vec, iter, start) \ + for (iter = (start); \ + (iter).bi_size && \ + ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ + bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len)) + +#endif /* __LINUX_BVEC_ITER_H */ -- 2.7.4