From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f44.google.com ([74.125.82.44]:52272 "EHLO mail-wg0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754602AbaLVLtu (ORCPT ); Mon, 22 Dec 2014 06:49:50 -0500 Received: by mail-wg0-f44.google.com with SMTP id b13so6470258wgh.3 for ; Mon, 22 Dec 2014 03:49:49 -0800 (PST) From: Dongsu Park To: linux-kernel@vger.kernel.org Cc: Jens Axboe , Kent Overstreet , Ming Lin , Dongsu Park , Chris Mason , Josef Bacik , linux-btrfs@vger.kernel.org Subject: [RFC PATCH 05/17] btrfs: remove bio splitting and merge_bvec_fn() calls Date: Mon, 22 Dec 2014 12:48:32 +0100 Message-Id: In-Reply-To: References: In-Reply-To: References: Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Kent Overstreet Btrfs has been doing bio splitting from btrfs_map_bio(), by checking device limits as well as calling ->merge_bvec_fn() etc. That is not necessary any more, because generic_make_request() is now able to handle arbitrarily sized bios. So clean up unnecessary code paths. Signed-off-by: Kent Overstreet [dpark: add more description in commit message] Signed-off-by: Dongsu Park Cc: Chris Mason Cc: Josef Bacik Cc: linux-btrfs@vger.kernel.org --- fs/btrfs/volumes.c | 73 ------------------------------------------------------ 1 file changed, 73 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 50c5a87..c627bf8 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -5691,34 +5691,6 @@ static noinline void btrfs_schedule_bio(struct btrfs_root *root, &device->work); } -static int bio_size_ok(struct block_device *bdev, struct bio *bio, - sector_t sector) -{ - struct bio_vec *prev; - struct request_queue *q = bdev_get_queue(bdev); - unsigned int max_sectors = queue_max_sectors(q); - struct bvec_merge_data bvm = { - .bi_bdev = bdev, - .bi_sector = sector, - .bi_rw = bio->bi_rw, - }; - - if (WARN_ON(bio->bi_vcnt == 0)) - return 1; - - prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; - if (bio_sectors(bio) > max_sectors) - return 0; - - if (!q->merge_bvec_fn) - return 1; - - bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len; - if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) - return 0; - return 1; -} - static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, struct bio *bio, u64 physical, int dev_nr, int rw, int async) @@ -5752,38 +5724,6 @@ static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, btrfsic_submit_bio(rw, bio); } -static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, - struct bio *first_bio, struct btrfs_device *dev, - int dev_nr, int rw, int async) -{ - struct bio_vec *bvec = first_bio->bi_io_vec; - struct bio *bio; - int nr_vecs = bio_get_nr_vecs(dev->bdev); - u64 physical = bbio->stripes[dev_nr].physical; - -again: - bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); - if (!bio) - return -ENOMEM; - - while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { - if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, - bvec->bv_offset) < bvec->bv_len) { - u64 len = bio->bi_iter.bi_size; - - atomic_inc(&bbio->stripes_pending); - submit_stripe_bio(root, bbio, bio, physical, dev_nr, - rw, async); - physical += len; - goto again; - } - bvec++; - } - - submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); - return 0; -} - static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) { atomic_inc(&bbio->error); @@ -5862,19 +5802,6 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, continue; } - /* - * Check and see if we're ok with this bio based on it's size - * and offset with the given device. - */ - if (!bio_size_ok(dev->bdev, first_bio, - bbio->stripes[dev_nr].physical >> 9)) { - ret = breakup_stripe_bio(root, bbio, first_bio, dev, - dev_nr, rw, async_submit); - BUG_ON(ret); - dev_nr++; - continue; - } - if (dev_nr < total_devs - 1) { bio = btrfs_bio_clone(first_bio, GFP_NOFS); BUG_ON(!bio); /* -ENOMEM */ -- 2.1.0