[PATCH v4 04/10] blk-mq: Check blk_mq_debugfs_register() return value

Bart Van Assche
2017-04-21T23:40:20Z

Make __blk_mq_register_dev() check the blk_mq_debugfs_register()
return value. In the error path, only unregister hctxs for which
registration succeeded.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
---
block/blk-mq-sysfs.c | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index c2cac20d981d..5f66a7798878 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -318,21 +318,32 @@ int __blk_mq_register_dev(struct device *dev, struct request_queue *q)

kobject_uevent(&q->mq_kobj, KOBJ_ADD);

- blk_mq_debugfs_register(q);
+ ret = blk_mq_debugfs_register(q);
+ if (ret)
+ goto remove;

queue_for_each_hw_ctx(q, hctx, i) {
ret = blk_mq_register_hctx(hctx);
if (ret)
- break;
+ goto unreg;
}

- if (ret)
- __blk_mq_unregister_dev(dev, q);
- else
- q->mq_sysfs_init_done = true;
+ q->mq_sysfs_init_done = true;

out:
return ret;
+
+unreg:
+ while (--i >= 0)
+ blk_mq_unregister_hctx(hctx);
+
+ blk_mq_debugfs_unregister_mq(q);
+
+remove:
+ kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
+ kobject_del(&q->mq_kobj);
+ kobject_put(&dev->kobj);
+ goto out;
}

int blk_mq_register_dev(struct device *dev, struct request_queue *q)
--
2.12.2