Merge tag 'for-linus-20181123' of git://git.kernel.dk/linux-block

Pull block fix from Jens Axboe:
 "Just a single fix for this week, fixing an issue with nvme-fc"

* tag 'for-linus-20181123' of git://git.kernel.dk/linux-block:
  nvme-fc: resolve io failures during connect

1 files changed, 63 insertions, 10 deletions

diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 0b70c8bab045..54032c466636 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -152,6 +152,7 @@ struct nvme_fc_ctrl {
 
         bool                    ioq_live;
         bool                    assoc_active;
+        atomic_t                err_work_active;
         u64                     association_id;
 
         struct list_head        ctrl_list;      /* rport->ctrl_list */
@@ -160,6 +161,7 @@ struct nvme_fc_ctrl {
         struct blk_mq_tag_set   tag_set;
 
         struct delayed_work     connect_work;
+        struct work_struct      err_work;
 
         struct kref             ref;
         u32                     flags;
@@ -1531,6 +1533,10 @@ nvme_fc_abort_aen_ops(struct nvme_fc_ctrl *ctrl)
         struct nvme_fc_fcp_op *aen_op = ctrl->aen_ops;
         int i;
 
+        /* ensure we've initialized the ops once */
+        if (!(aen_op->flags & FCOP_FLAGS_AEN))
+                return;
+
         for (i = 0; i < NVME_NR_AEN_COMMANDS; i++, aen_op++)
                 __nvme_fc_abort_op(ctrl, aen_op);
 }
@@ -2049,7 +2055,25 @@ nvme_fc_nvme_ctrl_freed(struct nvme_ctrl *nctrl)
 static void
 nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg)
 {
-        /* only proceed if in LIVE state - e.g. on first error */
+        int active;
+
+        /*
+         * if an error (io timeout, etc) while (re)connecting,
+         * it's an error on creating the new association.
+         * Start the error recovery thread if it hasn't already
+         * been started. It is expected there could be multiple
+         * ios hitting this path before things are cleaned up.
+         */
+        if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {
+                active = atomic_xchg(&ctrl->err_work_active, 1);
+                if (!active && !schedule_work(&ctrl->err_work)) {
+                        atomic_set(&ctrl->err_work_active, 0);
+                        WARN_ON(1);
+                }
+                return;
+        }
+
+        /* Otherwise, only proceed if in LIVE state - e.g. on first error */
         if (ctrl->ctrl.state != NVME_CTRL_LIVE)
                 return;
 
@@ -2814,6 +2838,7 @@ nvme_fc_delete_ctrl(struct nvme_ctrl *nctrl)
 {
         struct nvme_fc_ctrl *ctrl = to_fc_ctrl(nctrl);
 
+        cancel_work_sync(&ctrl->err_work);
         cancel_delayed_work_sync(&ctrl->connect_work);
         /*
          * kill the association on the link side.  this will block
@@ -2866,23 +2891,30 @@ nvme_fc_reconnect_or_delete(struct nvme_fc_ctrl *ctrl, int status)
 }
 
 static void
-nvme_fc_reset_ctrl_work(struct work_struct *work)
+__nvme_fc_terminate_io(struct nvme_fc_ctrl *ctrl)
 {
-        struct nvme_fc_ctrl *ctrl =
-                container_of(work, struct nvme_fc_ctrl, ctrl.reset_work);
-        int ret;
-
-        nvme_stop_ctrl(&ctrl->ctrl);
+        nvme_stop_keep_alive(&ctrl->ctrl);
 
         /* will block will waiting for io to terminate */
         nvme_fc_delete_association(ctrl);
 
-        if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
+        if (ctrl->ctrl.state != NVME_CTRL_CONNECTING &&
+            !nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING))
                 dev_err(ctrl->ctrl.device,
                         "NVME-FC{%d}: error_recovery: Couldn't change state "
                         "to CONNECTING\n", ctrl->cnum);
-                return;
-        }
+}
+
+static void
+nvme_fc_reset_ctrl_work(struct work_struct *work)
+{
+        struct nvme_fc_ctrl *ctrl =
+                container_of(work, struct nvme_fc_ctrl, ctrl.reset_work);
+        int ret;
+
+        __nvme_fc_terminate_io(ctrl);
+
+        nvme_stop_ctrl(&ctrl->ctrl);
 
         if (ctrl->rport->remoteport.port_state == FC_OBJSTATE_ONLINE)
                 ret = nvme_fc_create_association(ctrl);
@@ -2897,6 +2929,24 @@ nvme_fc_reset_ctrl_work(struct work_struct *work)
                         ctrl->cnum);
 }
 
+static void
+nvme_fc_connect_err_work(struct work_struct *work)
+{
+        struct nvme_fc_ctrl *ctrl =
+                        container_of(work, struct nvme_fc_ctrl, err_work);
+
+        __nvme_fc_terminate_io(ctrl);
+
+        atomic_set(&ctrl->err_work_active, 0);
+
+        /*
+         * Rescheduling the connection after recovering
+         * from the io error is left to the reconnect work
+         * item, which is what should have stalled waiting on
+         * the io that had the error that scheduled this work.
+         */
+}
+
 static const struct nvme_ctrl_ops nvme_fc_ctrl_ops = {
         .name                   = "fc",
         .module                 = THIS_MODULE,
@@ -3007,6 +3057,7 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
         ctrl->cnum = idx;
         ctrl->ioq_live = false;
         ctrl->assoc_active = false;
+        atomic_set(&ctrl->err_work_active, 0);
         init_waitqueue_head(&ctrl->ioabort_wait);
 
         get_device(ctrl->dev);
@@ -3014,6 +3065,7 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
 
         INIT_WORK(&ctrl->ctrl.reset_work, nvme_fc_reset_ctrl_work);
         INIT_DELAYED_WORK(&ctrl->connect_work, nvme_fc_connect_ctrl_work);
+        INIT_WORK(&ctrl->err_work, nvme_fc_connect_err_work);
         spin_lock_init(&ctrl->lock);
 
         /* io queue count */
@@ -3103,6 +3155,7 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
 fail_ctrl:
         nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING);
         cancel_work_sync(&ctrl->ctrl.reset_work);
+        cancel_work_sync(&ctrl->err_work);
         cancel_delayed_work_sync(&ctrl->connect_work);
 
         ctrl->ctrl.opts = NULL;