Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756198Ab3IYUZj (ORCPT ); Wed, 25 Sep 2013 16:25:39 -0400 Received: from mail-pb0-f51.google.com ([209.85.160.51]:48737 "EHLO mail-pb0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755942Ab3IYUWx (ORCPT ); Wed, 25 Sep 2013 16:22:53 -0400 From: Kent Overstreet To: hch@infradead.org, axboe@kernel.dk, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Kent Overstreet Subject: [PATCH 1/6] block: Introduce bio_for_each_page() Date: Wed, 25 Sep 2013 13:22:39 -0700 Message-Id: <1380140564-9030-2-git-send-email-kmo@daterainc.com> X-Mailer: git-send-email 1.8.4.rc3 In-Reply-To: <1380140564-9030-1-git-send-email-kmo@daterainc.com> References: <1380140564-9030-1-git-send-email-kmo@daterainc.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8570 Lines: 261 Prep work for multipage bvecs: various code will still need to iterate over individual pages, so we add primitives to do so Signed-off-by: Kent Overstreet --- drivers/scsi/sd_dif.c | 4 +-- fs/bio.c | 20 +++++++----- fs/mpage.c | 8 ++--- include/linux/bio.h | 85 ++++++++++++++++++++++++++++++++++----------------- 4 files changed, 76 insertions(+), 41 deletions(-) diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c index a7a691d..ea92592 100644 --- a/drivers/scsi/sd_dif.c +++ b/drivers/scsi/sd_dif.c @@ -385,7 +385,7 @@ void sd_dif_prepare(struct request *rq, sector_t hw_sector, virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff; - bip_for_each_vec(iv, bio->bi_integrity, iter) { + bip_for_each_page(iv, bio->bi_integrity, iter) { sdt = kmap_atomic(iv.bv_page) + iv.bv_offset; @@ -436,7 +436,7 @@ void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes) virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff; - bip_for_each_vec(iv, bio->bi_integrity, iter) { + bip_for_each_page(iv, bio->bi_integrity, iter) { sdt = kmap_atomic(iv.bv_page) + iv.bv_offset; diff --git a/fs/bio.c b/fs/bio.c index e9d1c05..da8aa81 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -496,16 +496,22 @@ EXPORT_SYMBOL(bio_alloc_bioset); void zero_fill_bio(struct bio *bio) { - unsigned long flags; struct bio_vec bv; struct bvec_iter iter; - bio_for_each_segment(bv, bio, iter) { +#if defined(CONFIG_HIGHMEM) || defined(ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE) + bio_for_each_page(bv, bio, iter) { + unsigned long flags; char *data = bvec_kmap_irq(&bv, &flags); memset(data, 0, bv.bv_len); flush_dcache_page(bv.bv_page); bvec_kunmap_irq(data, &flags); } +#else + bio_for_each_segment(bv, bio, iter) + memset(page_address(bv.bv_page) + bv.bv_offset, + 0, bv.bv_len); +#endif } EXPORT_SYMBOL(zero_fill_bio); @@ -1474,11 +1480,11 @@ EXPORT_SYMBOL(bio_copy_kern); */ void bio_set_pages_dirty(struct bio *bio) { - struct bio_vec *bvec; - int i; + struct bio_vec bvec; + struct bvec_iter iter; - bio_for_each_segment_all(bvec, bio, i) { - struct page *page = bvec->bv_page; + bio_for_each_page_all(bvec, bio, iter) { + struct page *page = bvec.bv_page; if (page && !PageCompound(page)) set_page_dirty_lock(page); @@ -1574,7 +1580,7 @@ void bio_flush_dcache_pages(struct bio *bi) struct bio_vec *bvec; struct bvec_iter iter; - bio_for_each_segment(bvec, bi, iter) + bio_for_each_page(bvec, bi, iter) flush_dcache_page(bvec->bv_page); } EXPORT_SYMBOL(bio_flush_dcache_pages); diff --git a/fs/mpage.c b/fs/mpage.c index 8e0a471..7507811 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -43,11 +43,11 @@ */ static void mpage_end_io(struct bio *bio, int err) { - struct bio_vec *bv; - int i; + struct bio_vec bv; + struct bvec_iter iter; - bio_for_each_segment_all(bv, bio, i) { - struct page *page = bv->bv_page; + bio_for_each_page_all(bv, bio, iter) { + struct page *page = bv.bv_page; if (bio_data_dir(bio) == READ) { if (!err) { diff --git a/include/linux/bio.h b/include/linux/bio.h index 231ae67..f6f0e99 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -63,16 +63,24 @@ */ #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_page(bvec, iter) \ + nth_page(__bvec_iter_bvec((bvec), (iter))->bv_page, \ + __bvec_iter_offset((bvec), (iter)) >> PAGE_SHIFT) -#define bvec_iter_len(bvec, iter) \ - min((iter).bi_size, \ +#define bvec_iter_page_bytes(bvec, iter) \ + min_t(unsigned, bvec_iter_len((bvec), (iter)), \ + PAGE_SIZE - bvec_iter_offset((bvec), (iter))) + +#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) \ +#define __bvec_iter_offset(bvec, iter) \ (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done) +#define bvec_iter_offset(bvec, iter) \ + (__bvec_iter_offset((bvec), (iter)) & (PAGE_SIZE - 1)) + #define bvec_iter_bvec(bvec, iter) \ ((struct bio_vec) { \ .bv_page = bvec_iter_page((bvec), (iter)), \ @@ -85,6 +93,8 @@ #define bio_iter_page(bio, iter) \ bvec_iter_page((bio)->bi_io_vec, (iter)) +#define bio_iter_page_bytes(bio, iter) \ + bvec_iter_page_bytes((bio)->bi_io_vec, (iter)) #define bio_iter_len(bio, iter) \ bvec_iter_len((bio)->bi_io_vec, (iter)) #define bio_iter_offset(bio, iter) \ @@ -188,13 +198,6 @@ static inline void *bio_data(struct bio *bio) #define bio_io_error(bio) bio_endio((bio), -EIO) -/* - * drivers should _never_ use the all version - the bio may have been split - * before it got to the driver and the driver won't own all of it - */ -#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) { @@ -215,13 +218,6 @@ static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter, } } -#define for_each_bvec(bvl, bio_vec, iter, start) \ - for ((iter) = start; \ - (bvl) = bvec_iter_bvec((bio_vec), (iter)), \ - (iter).bi_size; \ - bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len)) - - static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, unsigned bytes) { @@ -233,15 +229,42 @@ static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, bvec_iter_advance(bio->bi_io_vec, iter, bytes); } -#define __bio_for_each_segment(bvl, bio, iter, start) \ +#define BVEC_ITER_ALL_INITIALIZER (struct bvec_iter) \ +{ \ + .bi_sector = 0, \ + .bi_size = UINT_MAX, \ + .bi_idx = 0, \ + .bi_bvec_done = 0, \ +} + +#define __bio_for_each(bvl, bio, iter, start, condition, advance) \ for (iter = (start); \ - (iter).bi_size && \ - ((bvl = bio_iter_iovec((bio), (iter))), 1); \ - bio_advance_iter((bio), &(iter), (bvl).bv_len)) + (condition) && \ + ((bvl) = bio_iter_iovec((bio), (iter)), 1); \ + bio_advance_iter((bio), &(iter), advance((bio), (iter)))) + +#define __bio_for_each_segment(bvl, bio, iter, start) \ + __bio_for_each((bvl), (bio), (iter), (start), \ + (iter).bi_size, bio_iter_len) #define bio_for_each_segment(bvl, bio, iter) \ __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) +#define bio_for_each_page(bvl, bio, iter) \ + __bio_for_each((bvl), (bio), (iter), (bio)->bi_iter, \ + (iter).bi_size, bio_iter_page_bytes) + +/* + * drivers should _never_ use the all version - the bio may have been split + * before it got to the driver and the driver won't own all of it + */ +#define bio_for_each_segment_all(bvl, bio, i) \ + for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++) + +#define bio_for_each_page_all(bvl, bio, iter) \ + __bio_for_each((bvl), (bio), (iter), BVEC_ITER_ALL_INITIALIZER, \ + (iter).bi_idx < (bio)->bi_vcnt, bio_iter_page_bytes) + #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) /* @@ -616,16 +639,22 @@ struct biovec_slab { #if defined(CONFIG_BLK_DEV_INTEGRITY) +#define __bip_for_each(bvl, bip, iter, advance) \ + for ((iter) = (bip)->bip_iter; \ + (iter).bi_size && \ + ((bvl) = bvec_iter_bvec((bip)->bip_vec, (iter)), 1); \ + bvec_iter_advance((bip)->bip_vec, &(iter), \ + advance((bip)->bip_vec, (iter)))) +#define bip_for_each_segment(bvl, bip, iter) \ + __bip_for_each(bvl, bip, iter, bvec_iter_len) -#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)])) - -#define bip_for_each_vec(bvl, bip, iter) \ - for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) +#define bip_for_each_page(bvl, bip, iter) \ + __bip_for_each(bvl, bip, iter, bvec_iter_page_bytes) #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ for_each_bio(_bio) \ - bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) + bip_for_each_segment(_bvl, _bio->bi_integrity, _iter) #define bio_integrity(bio) (bio->bi_integrity != NULL) -- 1.8.4.rc3 -- 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/