From bea2771871ed1084c9a85ed0c86340f188505702 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 1 May 2006 12:15:46 -0700 Subject: [PATCH] md: Change ENOTSUPP to EOPNOTSUPP Because that is what you get if a BIO_RW_BARRIER isn't supported! Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/raid1.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/md/raid1.c') diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 6081941de1b3..532d04077301 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -315,7 +315,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int if (r1_bio->bios[mirror] == bio) break; - if (error == -ENOTSUPP && test_bit(R1BIO_Barrier, &r1_bio->state)) { + if (error == -EOPNOTSUPP && test_bit(R1BIO_Barrier, &r1_bio->state)) { set_bit(BarriersNotsupp, &conf->mirrors[mirror].rdev->flags); set_bit(R1BIO_BarrierRetry, &r1_bio->state); r1_bio->mddev->barriers_work = 0; @@ -1404,7 +1404,7 @@ static void raid1d(mddev_t *mddev) unplug = 1; } else if (test_bit(R1BIO_BarrierRetry, &r1_bio->state)) { /* some requests in the r1bio were BIO_RW_BARRIER - * requests which failed with -ENOTSUPP. Hohumm.. + * requests which failed with -EOPNOTSUPP. Hohumm.. * Better resubmit without the barrier. * We know which devices to resubmit for, because * all others have had their bios[] entry cleared. -- cgit v1.2.3 From 62de608da0b0ab17d81a233b50d1e952b9816f69 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 1 May 2006 12:15:47 -0700 Subject: [PATCH] md: Improve detection of lack of barrier support in raid1 Move the test for 'do barrier work' down a bit so that if the first write to a raid1 is a BIO_RW_BARRIER write, the checking done by superblock writes will cause the right thing to happen. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/raid1.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'drivers/md/raid1.c') diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 532d04077301..b8c13c897ccb 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -753,18 +753,24 @@ static int make_request(request_queue_t *q, struct bio * bio) const int rw = bio_data_dir(bio); int do_barriers; - if (unlikely(!mddev->barriers_work && bio_barrier(bio))) { - bio_endio(bio, bio->bi_size, -EOPNOTSUPP); - return 0; - } - /* * Register the new request and wait if the reconstruction * thread has put up a bar for new requests. * Continue immediately if no resync is active currently. + * We test barriers_work *after* md_write_start as md_write_start + * may cause the first superblock write, and that will check out + * if barriers work. */ + md_write_start(mddev, bio); /* wait on superblock update early */ + if (unlikely(!mddev->barriers_work && bio_barrier(bio))) { + if (rw == WRITE) + md_write_end(mddev); + bio_endio(bio, bio->bi_size, -EOPNOTSUPP); + return 0; + } + wait_barrier(conf); disk_stat_inc(mddev->gendisk, ios[rw]); -- cgit v1.2.3 From 5e7dd2ab6b9bdfa60e19b8739e6b2a204fd4f477 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 1 May 2006 12:15:47 -0700 Subject: [PATCH] md: Fix 'rdev->nr_pending' count when retrying barrier requests When retrying a failed BIO_RW_BARRIER request, we need to keep the reference in ->nr_pending over the whole retry. Currently, we only hold the reference if the failed request is the *last* one to finish - which is silly, because it would normally be the first to finish. So move the rdev_dec_pending call up into the didn't-fail branch. As the rdev isn't used in the later code, calling rdev_dec_pending earlier doesn't hurt. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/raid1.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'drivers/md/raid1.c') diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index b8c13c897ccb..4070eff6f0f8 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -319,6 +319,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int set_bit(BarriersNotsupp, &conf->mirrors[mirror].rdev->flags); set_bit(R1BIO_BarrierRetry, &r1_bio->state); r1_bio->mddev->barriers_work = 0; + /* Don't rdev_dec_pending in this branch - keep it for the retry */ } else { /* * this branch is our 'one mirror IO has finished' event handler: @@ -365,6 +366,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int } } } + rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); } /* * @@ -374,11 +376,9 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int if (atomic_dec_and_test(&r1_bio->remaining)) { if (test_bit(R1BIO_BarrierRetry, &r1_bio->state)) { reschedule_retry(r1_bio); - /* Don't dec_pending yet, we want to hold - * the reference over the retry - */ goto out; } + /* it really is the end of this request */ if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { /* free extra copy of the data pages */ int i = bio->bi_vcnt; @@ -393,8 +393,6 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int md_write_end(r1_bio->mddev); raid_end_bio_io(r1_bio); } - - rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); out: if (to_put) bio_put(to_put); @@ -1414,6 +1412,7 @@ static void raid1d(mddev_t *mddev) * Better resubmit without the barrier. * We know which devices to resubmit for, because * all others have had their bios[] entry cleared. + * We already have a nr_pending reference on these rdevs. */ int i; clear_bit(R1BIO_BarrierRetry, &r1_bio->state); -- cgit v1.2.3