NVMe: Unify controller probe and resume

[linux-2.6-block.git] / drivers / block / nvme-core.c

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 2cbe1b4daef277d8bddd21451c5bfd65b48c2a70..01a68250f8682de11c3a853e80f0edfbfb7f7d4f 100644 (file)
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -2361,19 +2361,20 @@ static int nvme_dev_add(struct nvme_dev *dev)
        }
        kfree(ctrl);
 
-       dev->tagset.ops = &nvme_mq_ops;
-       dev->tagset.nr_hw_queues = dev->online_queues - 1;
-       dev->tagset.timeout = NVME_IO_TIMEOUT;
-       dev->tagset.numa_node = dev_to_node(dev->dev);
-       dev->tagset.queue_depth =
+       if (!dev->tagset.tags) {
+               dev->tagset.ops = &nvme_mq_ops;
+               dev->tagset.nr_hw_queues = dev->online_queues - 1;
+               dev->tagset.timeout = NVME_IO_TIMEOUT;
+               dev->tagset.numa_node = dev_to_node(dev->dev);
+               dev->tagset.queue_depth =
                                min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
-       dev->tagset.cmd_size = nvme_cmd_size(dev);
-       dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
-       dev->tagset.driver_data = dev;
-
-       if (blk_mq_alloc_tag_set(&dev->tagset))
-               return 0;
+               dev->tagset.cmd_size = nvme_cmd_size(dev);
+               dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
+               dev->tagset.driver_data = dev;
 
+               if (blk_mq_alloc_tag_set(&dev->tagset))
+                       return 0;
+       }
        schedule_work(&dev->scan_work);
        return 0;
 }
@@ -2924,7 +2925,7 @@ static int nvme_dev_resume(struct nvme_dev *dev)
                spin_unlock(&dev_list_lock);
        } else {
                nvme_unfreeze_queues(dev);
-               schedule_work(&dev->scan_work);
+               nvme_dev_add(dev);
                nvme_set_irq_hints(dev);
        }
        return 0;
@@ -2932,8 +2933,17 @@ static int nvme_dev_resume(struct nvme_dev *dev)
 
 static void nvme_dev_reset(struct nvme_dev *dev)
 {
+       bool in_probe = work_busy(&dev->probe_work);
+
        nvme_dev_shutdown(dev);
-       if (nvme_dev_resume(dev)) {
+
+       /* Synchronize with device probe so that work will see failure status
+        * and exit gracefully without trying to schedule another reset */
+       flush_work(&dev->probe_work);
+
+       /* Fail this device if reset occured during probe to avoid
+        * infinite initialization loops. */
+       if (in_probe) {
                dev_warn(dev->dev, "Device failed to resume\n");
                kref_get(&dev->kref);
                if (IS_ERR(kthread_run(nvme_remove_dead_ctrl, dev, "nvme%d",
@@ -2942,7 +2952,11 @@ static void nvme_dev_reset(struct nvme_dev *dev)
                                "Failed to start controller remove task\n");
                        kref_put(&dev->kref, nvme_free_dev);
                }
+               return;
        }
+       /* Schedule device resume asynchronously so the reset work is available
+        * to cleanup errors that may occur during reinitialization */
+       schedule_work(&dev->probe_work);
 }
 
 static void nvme_reset_failed_dev(struct work_struct *ws)
@@ -2974,6 +2988,7 @@ static int nvme_reset(struct nvme_dev *dev)
 
        if (!ret) {
                flush_work(&dev->reset_work);
+               flush_work(&dev->probe_work);
                return 0;
        }
 
@@ -3070,18 +3085,9 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 static void nvme_async_probe(struct work_struct *work)
 {
        struct nvme_dev *dev = container_of(work, struct nvme_dev, probe_work);
-       int result;
-
-       result = nvme_dev_start(dev);
-       if (result)
-               goto reset;
 
-       if (dev->online_queues > 1)
-               result = nvme_dev_add(dev);
-       if (result)
+       if (nvme_dev_resume(dev))
                goto reset;
-
-       nvme_set_irq_hints(dev);
        return;
  reset:
        spin_lock(&dev_list_lock);