nvme-pci: do not try to add queue maps at runtime

The block layer allocates the set's maps once. We can't add special
purpose queues at runtime if they weren't allocated at initialization
time.

Tested-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index c63efa49132f9da9a4e2b012f0eeeb116ef966bc..0c1a8d7aa1c0bd1cf9a3991062820e42a1e14ddf 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2902,6 +2902,18 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
        dev->nr_write_queues = write_queues;
        dev->nr_poll_queues = poll_queues;
 
+       if (dev->ctrl.tagset) {
+               /*
+                * The set's maps are allocated only once at initialization
+                * time. We can't add special queues later if their mq_map
+                * wasn't preallocated.
+                */
+               if (dev->ctrl.tagset->nr_maps < 3)
+                       dev->nr_poll_queues = 0;
+               if (dev->ctrl.tagset->nr_maps < 2)
+                       dev->nr_write_queues = 0;
+       }
+
        /*
         * The initial number of allocated queue slots may be too large if the
         * user reduced the special queue parameters. Cap the value to the