NVMe: Schedule reset for failed controllers

Schedules a controller reset when it indicates it has a failed status. If
the device does not become ready after a reset, the pci device will be
scheduled for removal.

Signed-off-by: Keith Busch <keith.busch@intel.com>
[fixed checkpatch issue]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

2 files changed, 20 insertions, 2 deletions

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 000bca43c23b..2f5b9f5f5a21 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -60,6 +60,8 @@ static LIST_HEAD(dev_list);
 static struct task_struct *nvme_thread;
 static struct workqueue_struct *nvme_workq;
 
+static void nvme_reset_failed_dev(struct work_struct *ws);
+
 /*
  * An NVM Express queue.  Each device has at least two (one for admin
  * commands and one for I/O commands).
@@ -1612,13 +1614,25 @@ static void nvme_resubmit_bios(struct nvme_queue *nvmeq)
 
 static int nvme_kthread(void *data)
 {
-        struct nvme_dev *dev;
+        struct nvme_dev *dev, *next;
 
         while (!kthread_should_stop()) {
                 set_current_state(TASK_INTERRUPTIBLE);
                 spin_lock(&dev_list_lock);
-                list_for_each_entry(dev, &dev_list, node) {
+                list_for_each_entry_safe(dev, next, &dev_list, node) {
                         int i;
+                        if (readl(&dev->bar->csts) & NVME_CSTS_CFS &&
+                                                        dev->initialized) {
+                                if (work_busy(&dev->reset_work))
+                                        continue;
+                                list_del_init(&dev->node);
+                                dev_warn(&dev->pci_dev->dev,
+                                        "Failed status, reset controller\n");
+                                INIT_WORK(&dev->reset_work,
+                                                        nvme_reset_failed_dev);
+                                queue_work(nvme_workq, &dev->reset_work);
+                                continue;
+                        }
                         for (i = 0; i < dev->queue_count; i++) {
                                 struct nvme_queue *nvmeq = dev->queues[i];
                                 if (!nvmeq)
@@ -2006,6 +2020,7 @@ static void nvme_dev_shutdown(struct nvme_dev *dev)
 {
         int i;
 
+        dev->initialized = 0;
         for (i = dev->queue_count - 1; i >= 0; i--)
                 nvme_disable_queue(dev, i);
 
@@ -2196,6 +2211,7 @@ static int nvme_dev_resume(struct nvme_dev *dev)
                 queue_work(nvme_workq, &dev->reset_work);
                 spin_unlock(&dev_list_lock);
         }
+        dev->initialized = 1;
         return 0;
 }
 
@@ -2269,6 +2285,7 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
         if (result)
                 goto remove;
 
+        dev->initialized = 1;
         kref_init(&dev->kref);
         return 0;
 
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index eed81cc56d7e..117d877e8be5 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -95,6 +95,7 @@ struct nvme_dev {
         u32 max_hw_sectors;
         u32 stripe_size;
         u16 oncs;
+        u8 initialized;
 };
 
 /*