nvmet: mask pending AENs

Per section 5.2 of the NVMe 1.3 spec:

  "When the controller posts a completion queue entry for an outstanding
  Asynchronous Event Request command and thus reports an asynchronous
  event, subsequent events of that event type are automatically masked by
  the controller until the host clears that event. An event is cleared by
  reading the log page associated with that event using the Get Log Page
  command (see section 5.14)."

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

3 files changed, 10 insertions, 1 deletions

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 72ef17616682..ead8fbe6922e 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -144,6 +144,7 @@ static void nvmet_execute_get_log_changed_ns(struct nvmet_req *req)
         if (!status)
                 status = nvmet_zero_sgl(req, len, req->data_len - len);
         ctrl->nr_changed_ns = 0;
+        clear_bit(NVME_AEN_CFG_NS_ATTR, &ctrl->aen_masked);
         mutex_unlock(&ctrl->lock);
 out:
         nvmet_req_complete(req, status);
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 5a086b670f42..a03da764ecae 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -144,6 +144,13 @@ static void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
         schedule_work(&ctrl->async_event_work);
 }
 
+static bool nvmet_aen_disabled(struct nvmet_ctrl *ctrl, u32 aen)
+{
+        if (!(READ_ONCE(ctrl->aen_enabled) & aen))
+                return true;
+        return test_and_set_bit(aen, &ctrl->aen_masked);
+}
+
 static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid)
 {
         u32 i;
@@ -174,7 +181,7 @@ static void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid)
 
         list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
                 nvmet_add_to_changed_ns_log(ctrl, cpu_to_le32(nsid));
-                if (!(READ_ONCE(ctrl->aen_enabled) & NVME_AEN_CFG_NS_ATTR))
+                if (nvmet_aen_disabled(ctrl, NVME_AEN_CFG_NS_ATTR))
                         continue;
                 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE,
                                 NVME_AER_NOTICE_NS_CHANGED,
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index f4d16d9b3582..480dfe10fad9 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -139,6 +139,7 @@ struct nvmet_ctrl {
         u32                     kato;
 
         u32                     aen_enabled;
+        unsigned long           aen_masked;
         struct nvmet_req        *async_event_cmds[NVMET_ASYNC_EVENTS];
         unsigned int            nr_async_event_cmds;
         struct list_head        async_events;