diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 98c618e5732c..a8e3815295fe 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -108,6 +108,7 @@ struct nbd_device { struct nbd_config *config; struct mutex config_lock; struct gendisk *disk; + struct workqueue_struct *recv_workq; struct list_head list; struct task_struct *task_recv; @@ -139,7 +140,6 @@ static struct dentry *nbd_dbg_dir; static unsigned int nbds_max = 16; static int max_part = 16; -static struct workqueue_struct *recv_workqueue; static int part_shift; static int nbd_dev_dbg_init(struct nbd_device *nbd); @@ -1058,7 +1058,7 @@ static int nbd_reconnect_socket(struct nbd_device *nbd, unsigned long arg) /* We take the tx_mutex in an error path in the recv_work, so we * need to queue_work outside of the tx_mutex. */ - queue_work(recv_workqueue, &args->work); + queue_work(nbd->recv_workq, &args->work); atomic_inc(&config->live_connections); wake_up(&config->conn_wait); @@ -1159,6 +1159,10 @@ static void nbd_config_put(struct nbd_device *nbd) kfree(nbd->config); nbd->config = NULL; + if (nbd->recv_workq) + destroy_workqueue(nbd->recv_workq); + nbd->recv_workq = NULL; + nbd->tag_set.timeout = 0; nbd->disk->queue->limits.discard_granularity = 0; nbd->disk->queue->limits.discard_alignment = 0; @@ -1187,6 +1191,14 @@ static int nbd_start_device(struct nbd_device *nbd) return -EINVAL; } + nbd->recv_workq = alloc_workqueue("knbd%d-recv", + WQ_MEM_RECLAIM | WQ_HIGHPRI | + WQ_UNBOUND, 0, nbd->index); + if (!nbd->recv_workq) { + dev_err(disk_to_dev(nbd->disk), "Could not allocate knbd recv work queue.\n"); + return -ENOMEM; + } + blk_mq_update_nr_hw_queues(&nbd->tag_set, config->num_connections); nbd->task_recv = current; @@ -1217,7 +1229,7 @@ static int nbd_start_device(struct nbd_device *nbd) INIT_WORK(&args->work, recv_work); args->nbd = nbd; args->index = i; - queue_work(recv_workqueue, &args->work); + queue_work(nbd->recv_workq, &args->work); } nbd_size_update(nbd); return error; @@ -1237,8 +1249,10 @@ static int nbd_start_device_ioctl(struct nbd_device *nbd, struct block_device *b mutex_unlock(&nbd->config_lock); ret = wait_event_interruptible(config->recv_wq, atomic_read(&config->recv_threads) == 0); - if (ret) + if (ret) { sock_shutdown(nbd); + flush_workqueue(nbd->recv_workq); + } mutex_lock(&nbd->config_lock); nbd_bdev_reset(bdev); /* user requested, ignore socket errors */ @@ -1899,6 +1913,12 @@ static void nbd_disconnect_and_put(struct nbd_device *nbd) nbd_disconnect(nbd); nbd_clear_sock(nbd); mutex_unlock(&nbd->config_lock); + /* + * Make sure recv thread has finished, so it does not drop the last + * config ref and try to destroy the workqueue from inside the work + * queue. + */ + flush_workqueue(nbd->recv_workq); if (test_and_clear_bit(NBD_HAS_CONFIG_REF, &nbd->config->runtime_flags)) nbd_config_put(nbd); @@ -2283,20 +2303,12 @@ static int __init nbd_init(void) if (nbds_max > 1UL << (MINORBITS - part_shift)) return -EINVAL; - recv_workqueue = alloc_workqueue("knbd-recv", - WQ_MEM_RECLAIM | WQ_HIGHPRI | - WQ_UNBOUND, 0); - if (!recv_workqueue) - return -ENOMEM; - if (register_blkdev(NBD_MAJOR, "nbd")) { - destroy_workqueue(recv_workqueue); + if (register_blkdev(NBD_MAJOR, "nbd")) return -EIO; - } if (genl_register_family(&nbd_genl_family)) { unregister_blkdev(NBD_MAJOR, "nbd"); - destroy_workqueue(recv_workqueue); return -EINVAL; } nbd_dbg_init(); @@ -2338,7 +2350,6 @@ static void __exit nbd_cleanup(void) idr_destroy(&nbd_index_idr); genl_unregister_family(&nbd_genl_family); - destroy_workqueue(recv_workqueue); unregister_blkdev(NBD_MAJOR, "nbd"); }