+struct nvme_delq_ctx {
+ struct task_struct *waiter;
+ struct kthread_worker *worker;
+ atomic_t refcount;
+};
+
+static void nvme_wait_dq(struct nvme_delq_ctx *dq, struct nvme_dev *dev)
+{
+ dq->waiter = current;
+ mb();
+
+ for (;;) {
+ set_current_state(TASK_KILLABLE);
+ if (!atomic_read(&dq->refcount))
+ break;
+ if (!schedule_timeout(ADMIN_TIMEOUT) ||
+ fatal_signal_pending(current)) {
+ set_current_state(TASK_RUNNING);
+
+ nvme_disable_ctrl(dev, readq(&dev->bar->cap));
+ nvme_disable_queue(dev, 0);
+
+ send_sig(SIGKILL, dq->worker->task, 1);
+ flush_kthread_worker(dq->worker);
+ return;
+ }
+ }
+ set_current_state(TASK_RUNNING);
+}
+
+static void nvme_put_dq(struct nvme_delq_ctx *dq)
+{
+ atomic_dec(&dq->refcount);
+ if (dq->waiter)
+ wake_up_process(dq->waiter);
+}
+
+static struct nvme_delq_ctx *nvme_get_dq(struct nvme_delq_ctx *dq)
+{
+ atomic_inc(&dq->refcount);
+ return dq;
+}
+
+static void nvme_del_queue_end(struct nvme_queue *nvmeq)
+{
+ struct nvme_delq_ctx *dq = nvmeq->cmdinfo.ctx;
+
+ nvme_clear_queue(nvmeq);
+ nvme_put_dq(dq);
+}
+
+static int adapter_async_del_queue(struct nvme_queue *nvmeq, u8 opcode,
+ kthread_work_func_t fn)
+{
+ struct nvme_command c;
+
+ memset(&c, 0, sizeof(c));
+ c.delete_queue.opcode = opcode;
+ c.delete_queue.qid = cpu_to_le16(nvmeq->qid);
+
+ init_kthread_work(&nvmeq->cmdinfo.work, fn);
+ return nvme_submit_admin_cmd_async(nvmeq->dev, &c, &nvmeq->cmdinfo);
+}
+
+static void nvme_del_cq_work_handler(struct kthread_work *work)
+{
+ struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
+ cmdinfo.work);
+ nvme_del_queue_end(nvmeq);
+}
+
+static int nvme_delete_cq(struct nvme_queue *nvmeq)
+{
+ return adapter_async_del_queue(nvmeq, nvme_admin_delete_cq,
+ nvme_del_cq_work_handler);
+}
+
+static void nvme_del_sq_work_handler(struct kthread_work *work)
+{
+ struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
+ cmdinfo.work);
+ int status = nvmeq->cmdinfo.status;
+
+ if (!status)
+ status = nvme_delete_cq(nvmeq);
+ if (status)
+ nvme_del_queue_end(nvmeq);
+}
+
+static int nvme_delete_sq(struct nvme_queue *nvmeq)
+{
+ return adapter_async_del_queue(nvmeq, nvme_admin_delete_sq,
+ nvme_del_sq_work_handler);
+}
+
+static void nvme_del_queue_start(struct kthread_work *work)
+{
+ struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
+ cmdinfo.work);
+ allow_signal(SIGKILL);
+ if (nvme_delete_sq(nvmeq))
+ nvme_del_queue_end(nvmeq);
+}
+
+static void nvme_disable_io_queues(struct nvme_dev *dev)
+{
+ int i;
+ DEFINE_KTHREAD_WORKER_ONSTACK(worker);
+ struct nvme_delq_ctx dq;
+ struct task_struct *kworker_task = kthread_run(kthread_worker_fn,
+ &worker, "nvme%d", dev->instance);
+
+ if (IS_ERR(kworker_task)) {
+ dev_err(&dev->pci_dev->dev,
+ "Failed to create queue del task\n");
+ for (i = dev->queue_count - 1; i > 0; i--)
+ nvme_disable_queue(dev, i);
+ return;
+ }
+
+ dq.waiter = NULL;
+ atomic_set(&dq.refcount, 0);
+ dq.worker = &worker;
+ for (i = dev->queue_count - 1; i > 0; i--) {
+ struct nvme_queue *nvmeq = dev->queues[i];
+
+ if (nvme_suspend_queue(nvmeq))
+ continue;
+ nvmeq->cmdinfo.ctx = nvme_get_dq(&dq);
+ nvmeq->cmdinfo.worker = dq.worker;
+ init_kthread_work(&nvmeq->cmdinfo.work, nvme_del_queue_start);
+ queue_kthread_work(dq.worker, &nvmeq->cmdinfo.work);
+ }
+ nvme_wait_dq(&dq, dev);
+ kthread_stop(kworker_task);
+}
+