1 files changed, 79 insertions, 0 deletions
diff --git a/drivers/nvme/host/fault_inject.c b/drivers/nvme/host/fault_inject.c
new file mode 100644
index 000000000..02632266a
--- /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);