nvme-pci: Free tagset if no IO queues

If a controller becomes degraded after a reset, we will not be able to
perform any IO. We currently teardown previously created request
queues and namespaces, but we had kept the unusable tagset. Free
it after all queues using it have been released.

Tested-by: Edmund Nadolski <edmund.nadolski@intel.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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 78e4038236466c12d6f050bd314fe3814420ca7a..5c04581899f40c95a12deebc35bc57811dc82fa1 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2490,14 +2490,20 @@ static void nvme_release_prp_pools(struct nvme_dev *dev)
        dma_pool_destroy(dev->prp_small_pool);
 }
 
+static void nvme_free_tagset(struct nvme_dev *dev)
+{
+       if (dev->tagset.tags)
+               blk_mq_free_tag_set(&dev->tagset);
+       dev->ctrl.tagset = NULL;
+}
+
 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
 {
        struct nvme_dev *dev = to_nvme_dev(ctrl);
 
        nvme_dbbuf_dma_free(dev);
        put_device(dev->dev);
-       if (dev->tagset.tags)
-               blk_mq_free_tag_set(&dev->tagset);
+       nvme_free_tagset(dev);
        if (dev->ctrl.admin_q)
                blk_put_queue(dev->ctrl.admin_q);
        kfree(dev->queues);
@@ -2616,6 +2622,7 @@ static void nvme_reset_work(struct work_struct *work)
                nvme_kill_queues(&dev->ctrl);
                nvme_remove_namespaces(&dev->ctrl);
                new_state = NVME_CTRL_ADMIN_ONLY;
+               nvme_free_tagset(dev);
        } else {
                nvme_start_queues(&dev->ctrl);
                nvme_wait_freeze(&dev->ctrl);