v4.19.13 snapshot.
diff --git a/drivers/nvme/host/fault_inject.c b/drivers/nvme/host/fault_inject.c
new file mode 100644
index 0000000..0263226
--- /dev/null
+++ b/drivers/nvme/host/fault_inject.c
@@ -0,0 +1,79 @@
+/*
+ * fault injection support for nvme.
+ *
+ * Copyright (c) 2018, Oracle and/or its affiliates
+ *
+ */
+
+#include <linux/moduleparam.h>
+#include "nvme.h"
+
+static DECLARE_FAULT_ATTR(fail_default_attr);
+/* optional fault injection attributes boot time option:
+ * nvme_core.fail_request=<interval>,<probability>,<space>,<times>
+ */
+static char *fail_request;
+module_param(fail_request, charp, 0000);
+
+void nvme_fault_inject_init(struct nvme_ns *ns)
+{
+ struct dentry *dir, *parent;
+ char *name = ns->disk->disk_name;
+ struct nvme_fault_inject *fault_inj = &ns->fault_inject;
+ struct fault_attr *attr = &fault_inj->attr;
+
+ /* set default fault injection attribute */
+ if (fail_request)
+ setup_fault_attr(&fail_default_attr, fail_request);
+
+ /* create debugfs directory and attribute */
+ parent = debugfs_create_dir(name, NULL);
+ if (!parent) {
+ pr_warn("%s: failed to create debugfs directory\n", name);
+ return;
+ }
+
+ *attr = fail_default_attr;
+ dir = fault_create_debugfs_attr("fault_inject", parent, attr);
+ if (IS_ERR(dir)) {
+ pr_warn("%s: failed to create debugfs attr\n", name);
+ debugfs_remove_recursive(parent);
+ return;
+ }
+ ns->fault_inject.parent = parent;
+
+ /* create debugfs for status code and dont_retry */
+ fault_inj->status = NVME_SC_INVALID_OPCODE;
+ fault_inj->dont_retry = true;
+ debugfs_create_x16("status", 0600, dir, &fault_inj->status);
+ debugfs_create_bool("dont_retry", 0600, dir, &fault_inj->dont_retry);
+}
+
+void nvme_fault_inject_fini(struct nvme_ns *ns)
+{
+ /* remove debugfs directories */
+ debugfs_remove_recursive(ns->fault_inject.parent);
+}
+
+void nvme_should_fail(struct request *req)
+{
+ struct gendisk *disk = req->rq_disk;
+ struct nvme_ns *ns = NULL;
+ u16 status;
+
+ /*
+ * make sure this request is coming from a valid namespace
+ */
+ if (!disk)
+ return;
+
+ ns = disk->private_data;
+ if (ns && should_fail(&ns->fault_inject.attr, 1)) {
+ /* inject status code and DNR bit */
+ status = ns->fault_inject.status;
+ if (ns->fault_inject.dont_retry)
+ status |= NVME_SC_DNR;
+ nvme_req(req)->status = status;
+ }
+}
+EXPORT_SYMBOL_GPL(nvme_should_fail);