From 6b6c8110e173ce10f2b169d82a6670001f7184d1 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 15 Mar 2017 14:05:13 +1100 Subject: [PATCH] md/raid1, raid10: move rXbio accounting closer to allocation. When raid1 or raid10 find they will need to allocate a new r1bio/r10bio, in order to work around a known bad block, they account for the allocation well before the allocation is made. This separation makes the correctness less obvious and requires comments. The accounting needs to be a little before: before the first rXbio is submitted, but that is all. So move the accounting down to where it makes more sense. Signed-off-by: NeilBrown Signed-off-by: Shaohua Li --- drivers/md/raid1.c | 24 +++++++++++------------- drivers/md/raid10.c | 22 +++++++++------------- 2 files changed, 20 insertions(+), 26 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 730e57259af9..3afa60eb72c5 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1436,18 +1436,9 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio) goto retry_write; } - if (max_sectors < r1_bio->sectors) { - /* We are splitting this write into multiple parts, so - * we need to prepare for allocating another r1_bio. - */ + if (max_sectors < r1_bio->sectors) r1_bio->sectors = max_sectors; - spin_lock_irq(&conf->device_lock); - if (bio->bi_phys_segments == 0) - bio->bi_phys_segments = 2; - else - bio->bi_phys_segments++; - spin_unlock_irq(&conf->device_lock); - } + sectors_handled = r1_bio->sector + max_sectors - bio->bi_iter.bi_sector; atomic_set(&r1_bio->remaining, 1); @@ -1553,10 +1544,17 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio) * as it could result in the bio being freed. */ if (sectors_handled < bio_sectors(bio)) { - r1_bio_write_done(r1_bio); - /* We need another r1_bio. It has already been counted + /* We need another r1_bio, which must be accounted * in bio->bi_phys_segments */ + spin_lock_irq(&conf->device_lock); + if (bio->bi_phys_segments == 0) + bio->bi_phys_segments = 2; + else + bio->bi_phys_segments++; + spin_unlock_irq(&conf->device_lock); + + r1_bio_write_done(r1_bio); r1_bio = alloc_r1bio(mddev, bio, sectors_handled); goto retry_write; } diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index e89a8d78a9ed..c7c5b2693fc9 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1384,18 +1384,8 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, goto retry_write; } - if (max_sectors < r10_bio->sectors) { - /* We are splitting this into multiple parts, so - * we need to prepare for allocating another r10_bio. - */ + if (max_sectors < r10_bio->sectors) r10_bio->sectors = max_sectors; - spin_lock_irq(&conf->device_lock); - if (bio->bi_phys_segments == 0) - bio->bi_phys_segments = 2; - else - bio->bi_phys_segments++; - spin_unlock_irq(&conf->device_lock); - } sectors_handled = r10_bio->sector + max_sectors - bio->bi_iter.bi_sector; @@ -1505,10 +1495,16 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, */ if (sectors_handled < bio_sectors(bio)) { - one_write_done(r10_bio); - /* We need another r10_bio. It has already been counted + /* We need another r10_bio and it needs to be counted * in bio->bi_phys_segments. */ + spin_lock_irq(&conf->device_lock); + if (bio->bi_phys_segments == 0) + bio->bi_phys_segments = 2; + else + bio->bi_phys_segments++; + spin_unlock_irq(&conf->device_lock); + one_write_done(r10_bio); r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO); r10_bio->master_bio = bio; -- 2.45.2