1 files changed, 22 insertions, 8 deletions

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 8efa728f1eac..9f2b424c445e 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1739,10 +1739,15 @@ static int set_queue_count(struct nvme_dev *dev, int count)
         return min(result & 0xffff, result >> 16) + 1;
 }
 
+static size_t db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
+{
+        return 4096 + ((nr_io_queues + 1) << (dev->db_stride + 3));
+}
+
 static int nvme_setup_io_queues(struct nvme_dev *dev)
 {
         struct pci_dev *pdev = dev->pci_dev;
-        int result, cpu, i, vecs, nr_io_queues, db_bar_size, q_depth;
+        int result, cpu, i, vecs, nr_io_queues, size, q_depth;
 
         nr_io_queues = num_online_cpus();
         result = set_queue_count(dev, nr_io_queues);
@@ -1751,17 +1756,24 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
         if (result < nr_io_queues)
                 nr_io_queues = result;
 
-        /* Deregister the admin queue's interrupt */
-        free_irq(dev->entry[0].vector, dev->queues[0]);
-
-        db_bar_size = 4096 + ((nr_io_queues + 1) << (dev->db_stride + 3));
-        if (db_bar_size > 8192) {
+        size = db_bar_size(dev, nr_io_queues);
+        if (size > 8192) {
                 iounmap(dev->bar);
-                dev->bar = ioremap(pci_resource_start(pdev, 0), db_bar_size);
+                do {
+                        dev->bar = ioremap(pci_resource_start(pdev, 0), size);
+                        if (dev->bar)
+                                break;
+                        if (!--nr_io_queues)
+                                return -ENOMEM;
+                        size = db_bar_size(dev, nr_io_queues);
+                } while (1);
                 dev->dbs = ((void __iomem *)dev->bar) + 4096;
                 dev->queues[0]->q_db = dev->dbs;
         }
 
+        /* Deregister the admin queue's interrupt */
+        free_irq(dev->entry[0].vector, dev->queues[0]);
+
         vecs = nr_io_queues;
         for (i = 0; i < vecs; i++)
                 dev->entry[i].entry = i;
@@ -1799,8 +1811,10 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
         nr_io_queues = vecs;
 
         result = queue_request_irq(dev, dev->queues[0], "nvme admin");
-        if (result)
+        if (result) {
+                dev->queues[0]->q_suspended = 1;
                 goto free_queues;
+        }
 
         /* Free previously allocated queues that are no longer usable */
         spin_lock(&dev_list_lock);