From da9cf5050a2e3dbc3cf26a8d908482eb4485ed49 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 21 Feb 2011 18:25:57 +1100 Subject: [PATCH] md: avoid spinlock problem in blk_throtl_exit blk_throtl_exit assumes that ->queue_lock still exists, so make sure that it does. To do this, we stop redirecting ->queue_lock to conf->device_lock and leave it pointing where it is initialised - __queue_lock. As the blk_plug functions check the ->queue_lock is held, we now take that spin_lock explicitly around the plug functions. We don't need the locking, just the warning removal. This is needed for any kernel with the blk_throtl code, which is which is 2.6.37 and later. Cc: stable@kernel.org Signed-off-by: NeilBrown --- drivers/md/linear.c | 1 - drivers/md/multipath.c | 1 - drivers/md/raid0.c | 1 - drivers/md/raid1.c | 6 ++++-- drivers/md/raid10.c | 7 ++++--- drivers/md/raid5.c | 1 - 6 files changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/md/linear.c b/drivers/md/linear.c index 8a2f767f26d8..0ed7f6bc2a7f 100644 --- a/drivers/md/linear.c +++ b/drivers/md/linear.c @@ -216,7 +216,6 @@ static int linear_run (mddev_t *mddev) if (md_check_no_bitmap(mddev)) return -EINVAL; - mddev->queue->queue_lock = &mddev->queue->__queue_lock; conf = linear_conf(mddev, mddev->raid_disks); if (!conf) diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c index 6d7ddf32ef2e..3a62d440e27b 100644 --- a/drivers/md/multipath.c +++ b/drivers/md/multipath.c @@ -435,7 +435,6 @@ static int multipath_run (mddev_t *mddev) * bookkeeping area. [whatever we allocate in multipath_run(), * should be freed in multipath_stop()] */ - mddev->queue->queue_lock = &mddev->queue->__queue_lock; conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL); mddev->private = conf; diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index 75671dfee551..c0ac457f1218 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -361,7 +361,6 @@ static int raid0_run(mddev_t *mddev) if (md_check_no_bitmap(mddev)) return -EINVAL; blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); - mddev->queue->queue_lock = &mddev->queue->__queue_lock; /* if private is not null, we are here after takeover */ if (mddev->private == NULL) { diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index a23ffa397ba9..06cd712807d0 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -593,7 +593,10 @@ static int flush_pending_writes(conf_t *conf) if (conf->pending_bio_list.head) { struct bio *bio; bio = bio_list_get(&conf->pending_bio_list); + /* Only take the spinlock to quiet a warning */ + spin_lock(conf->mddev->queue->queue_lock); blk_remove_plug(conf->mddev->queue); + spin_unlock(conf->mddev->queue->queue_lock); spin_unlock_irq(&conf->device_lock); /* flush any pending bitmap writes to * disk before proceeding w/ I/O */ @@ -959,7 +962,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) atomic_inc(&r1_bio->remaining); spin_lock_irqsave(&conf->device_lock, flags); bio_list_add(&conf->pending_bio_list, mbio); - blk_plug_device(mddev->queue); + blk_plug_device_unlocked(mddev->queue); spin_unlock_irqrestore(&conf->device_lock, flags); } r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL); @@ -2021,7 +2024,6 @@ static int run(mddev_t *mddev) if (IS_ERR(conf)) return PTR_ERR(conf); - mddev->queue->queue_lock = &conf->device_lock; list_for_each_entry(rdev, &mddev->disks, same_set) { disk_stack_limits(mddev->gendisk, rdev->bdev, rdev->data_offset << 9); diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 3b607b28741b..747d061d8e05 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -662,7 +662,10 @@ static int flush_pending_writes(conf_t *conf) if (conf->pending_bio_list.head) { struct bio *bio; bio = bio_list_get(&conf->pending_bio_list); + /* Spinlock only taken to quiet a warning */ + spin_lock(conf->mddev->queue->queue_lock); blk_remove_plug(conf->mddev->queue); + spin_unlock(conf->mddev->queue->queue_lock); spin_unlock_irq(&conf->device_lock); /* flush any pending bitmap writes to disk * before proceeding w/ I/O */ @@ -971,7 +974,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) atomic_inc(&r10_bio->remaining); spin_lock_irqsave(&conf->device_lock, flags); bio_list_add(&conf->pending_bio_list, mbio); - blk_plug_device(mddev->queue); + blk_plug_device_unlocked(mddev->queue); spin_unlock_irqrestore(&conf->device_lock, flags); } @@ -2304,8 +2307,6 @@ static int run(mddev_t *mddev) if (!conf) goto out; - mddev->queue->queue_lock = &conf->device_lock; - mddev->thread = conf->thread; conf->thread = NULL; diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 702812824195..78536fdbd87f 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5204,7 +5204,6 @@ static int run(mddev_t *mddev) mddev->queue->backing_dev_info.congested_data = mddev; mddev->queue->backing_dev_info.congested_fn = raid5_congested; - mddev->queue->queue_lock = &conf->device_lock; mddev->queue->unplug_fn = raid5_unplug_queue; chunk_size = mddev->chunk_sectors << 9; -- 2.34.1