From cb34e057ad22a1c2c6f2cb6cd1cbd05cc2f28f28 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Wed, 5 Sep 2012 15:22:02 -0700 Subject: [PATCH] block: Convert some code to bio_for_each_segment_all() More prep work for immutable bvecs: A few places in the code were either open coding or using the wrong version - fix. After we introduce the bvec iter, it'll no longer be possible to modify the biovec through bio_for_each_segment_all() - it doesn't increment a pointer to the current bvec, you pass in a struct bio_vec (not a pointer) which is updated with what the current biovec would be (taking into account bi_bvec_done and bi_size). So because of that it's more worthwhile to be consistent about bio_for_each_segment()/bio_for_each_segment_all() usage. Signed-off-by: Kent Overstreet CC: Jens Axboe CC: NeilBrown CC: Alasdair Kergon CC: dm-devel@redhat.com CC: Alexander Viro --- drivers/md/dm-crypt.c | 3 +-- drivers/md/raid1.c | 10 +++------- fs/bio.c | 20 ++++++++++---------- fs/direct-io.c | 8 ++++---- mm/bounce.c | 2 +- 5 files changed, 19 insertions(+), 24 deletions(-) diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 13c1548..6d2d41a 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -858,8 +858,7 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) unsigned int i; struct bio_vec *bv; - for (i = 0; i < clone->bi_vcnt; i++) { - bv = bio_iovec_idx(clone, i); + bio_for_each_segment_all(bv, clone, i) { BUG_ON(!bv->bv_page); mempool_free(bv->bv_page, cc->page_pool); bv->bv_page = NULL; diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 8534820..a7ea954 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -925,7 +925,7 @@ static void alloc_behind_pages(struct bio *bio, struct r1bio *r1_bio) if (unlikely(!bvecs)) return; - bio_for_each_segment(bvec, bio, i) { + bio_for_each_segment_all(bvec, bio, i) { bvecs[i] = *bvec; bvecs[i].bv_page = alloc_page(GFP_NOIO); if (unlikely(!bvecs[i].bv_page)) @@ -1284,12 +1284,8 @@ read_again: struct bio_vec *bvec; int j; - /* Yes, I really want the '__' version so that - * we clear any unused pointer in the io_vec, rather - * than leave them unchanged. This is important - * because when we come to free the pages, we won't - * know the original bi_idx, so we just free - * them all + /* + * We trimmed the bio, so _all is legit */ bio_for_each_segment_all(bvec, mbio, j) bvec->bv_page = r1_bio->behind_bvecs[j].bv_page; diff --git a/fs/bio.c b/fs/bio.c index 618f904..fe3aee90 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -1548,11 +1548,11 @@ EXPORT_SYMBOL(bio_copy_kern); */ void bio_set_pages_dirty(struct bio *bio) { - struct bio_vec *bvec = bio->bi_io_vec; + struct bio_vec *bvec; int i; - for (i = 0; i < bio->bi_vcnt; i++) { - struct page *page = bvec[i].bv_page; + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; if (page && !PageCompound(page)) set_page_dirty_lock(page); @@ -1561,11 +1561,11 @@ void bio_set_pages_dirty(struct bio *bio) static void bio_release_pages(struct bio *bio) { - struct bio_vec *bvec = bio->bi_io_vec; + struct bio_vec *bvec; int i; - for (i = 0; i < bio->bi_vcnt; i++) { - struct page *page = bvec[i].bv_page; + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; if (page) put_page(page); @@ -1614,16 +1614,16 @@ static void bio_dirty_fn(struct work_struct *work) void bio_check_pages_dirty(struct bio *bio) { - struct bio_vec *bvec = bio->bi_io_vec; + struct bio_vec *bvec; int nr_clean_pages = 0; int i; - for (i = 0; i < bio->bi_vcnt; i++) { - struct page *page = bvec[i].bv_page; + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; if (PageDirty(page) || PageCompound(page)) { page_cache_release(page); - bvec[i].bv_page = NULL; + bvec->bv_page = NULL; } else { nr_clean_pages++; } diff --git a/fs/direct-io.c b/fs/direct-io.c index f853263..38484b0 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -441,8 +441,8 @@ static struct bio *dio_await_one(struct dio *dio) static int dio_bio_complete(struct dio *dio, struct bio *bio) { const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); - struct bio_vec *bvec = bio->bi_io_vec; - int page_no; + struct bio_vec *bvec; + unsigned i; if (!uptodate) dio->io_error = -EIO; @@ -450,8 +450,8 @@ static int dio_bio_complete(struct dio *dio, struct bio *bio) if (dio->is_async && dio->rw == READ) { bio_check_pages_dirty(bio); /* transfers ownership */ } else { - for (page_no = 0; page_no < bio->bi_vcnt; page_no++) { - struct page *page = bvec[page_no].bv_page; + bio_for_each_segment_all(bvec, bio, i) { + struct page *page = bvec->bv_page; if (dio->rw == READ && !PageCompound(page)) set_page_dirty_lock(page); diff --git a/mm/bounce.c b/mm/bounce.c index 2ee1b6f..f5326b2 100644 --- a/mm/bounce.c +++ b/mm/bounce.c @@ -231,7 +231,7 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig, bounce: bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set); - bio_for_each_segment(to, bio, i) { + bio_for_each_segment_all(to, bio, i) { struct page *page = to->bv_page; if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force) -- 2.7.4