Merge "block: Make del_gendisk() safer for disks without queues" (86066201) · Commits · e / devices / android_kernel_fairphone_FP3

block/blk-core.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -582,8 +582,6 @@ void blk_cleanup_queue(struct request_queue *q)
		q->queue_lock = &q->__queue_lock;
		spin_unlock_irq(lock);

		bdi_unregister(q->backing_dev_info);

		/* @q is and will stay empty, shutdown and put */
		blk_put_queue(q);
		}

block/genhd.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -660,7 +660,16 @@ void del_gendisk(struct gendisk *disk)
		disk->flags &= ~GENHD_FL_UP;

		sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
		if (disk->queue) {
		/*
		* Unregister bdi before releasing device numbers (as they can
		* get reused and we'd get clashes in sysfs).
		*/
		bdi_unregister(disk->queue->backing_dev_info);
		blk_unregister_queue(disk);
		} else {
		WARN_ON(1);
		}
		blk_unregister_region(disk_devt(disk), disk->minors);

		part_stat_set_all(&disk->part0, 0);

mm/backing-dev.c

+28 −15

Original line number	Diff line number	Diff line
		@@ -682,33 +682,26 @@ static int cgwb_bdi_init(struct backing_dev_info *bdi)
		static void cgwb_bdi_destroy(struct backing_dev_info *bdi)
		{
		struct radix_tree_iter iter;
		struct rb_node *rbn;
		void **slot;

		WARN_ON(test_bit(WB_registered, &bdi->wb.state));

		spin_lock_irq(&cgwb_lock);

		radix_tree_for_each_slot(slot, &bdi->cgwb_tree, &iter, 0)
		cgwb_kill(*slot);

		while ((rbn = rb_first(&bdi->cgwb_congested_tree))) {
		struct bdi_writeback_congested *congested =
		rb_entry(rbn, struct bdi_writeback_congested, rb_node);

		rb_erase(rbn, &bdi->cgwb_congested_tree);
		congested->bdi = NULL; /* mark @congested unlinked */
		}

		spin_unlock_irq(&cgwb_lock);

		/*
		* All cgwb's and their congested states must be shutdown and
		* released before returning. Drain the usage counter to wait for
		* all cgwb's and cgwb_congested's ever created on @bdi.
		* All cgwb's must be shutdown and released before returning. Drain
		* the usage counter to wait for all cgwb's ever created on @bdi.
		*/
		atomic_dec(&bdi->usage_cnt);
		wait_event(cgwb_release_wait, !atomic_read(&bdi->usage_cnt));
		/*
		* Grab back our reference so that we hold it when @bdi gets
		* re-registered.
		*/
		atomic_inc(&bdi->usage_cnt);
		}

		/**
		@@ -748,6 +741,21 @@ void wb_blkcg_offline(struct blkcg *blkcg)
		spin_unlock_irq(&cgwb_lock);
		}

		static void cgwb_bdi_exit(struct backing_dev_info *bdi)
		{
		struct rb_node *rbn;

		spin_lock_irq(&cgwb_lock);
		while ((rbn = rb_first(&bdi->cgwb_congested_tree))) {
		struct bdi_writeback_congested *congested =
		rb_entry(rbn, struct bdi_writeback_congested, rb_node);

		rb_erase(rbn, &bdi->cgwb_congested_tree);
		congested->bdi = NULL; /* mark @congested unlinked */
		}
		spin_unlock_irq(&cgwb_lock);
		}

		#else /* CONFIG_CGROUP_WRITEBACK */

		static int cgwb_bdi_init(struct backing_dev_info *bdi)
		@@ -768,7 +776,9 @@ static int cgwb_bdi_init(struct backing_dev_info *bdi)
		return 0;
		}

		static void cgwb_bdi_destroy(struct backing_dev_info *bdi)
		static void cgwb_bdi_destroy(struct backing_dev_info *bdi) { }

		static void cgwb_bdi_exit(struct backing_dev_info *bdi)
		{
		wb_congested_put(bdi->wb_congested);
		}
		@@ -856,6 +866,8 @@ int bdi_register_owner(struct backing_dev_info bdi, struct device owner)
		MINOR(owner->devt));
		if (rc)
		return rc;
		/* Leaking owner reference... */
		WARN_ON(bdi->owner);
		bdi->owner = owner;
		get_device(owner);
		return 0;
		@@ -897,6 +909,7 @@ static void bdi_exit(struct backing_dev_info *bdi)
		{
		WARN_ON_ONCE(bdi->dev);
		wb_exit(&bdi->wb);
		cgwb_bdi_exit(bdi);
		}

		static void release_bdi(struct kref *ref)