1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/nvme/host/fault_inject.c b/drivers/nvme/host/fault_inject.c
new file mode 100644
index 0000000000..1ba10a5c65
--- /dev/null
+++ b/drivers/nvme/host/fault_inject.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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_fault_inject *fault_inj,
+			    const char *dev_name)
+{
+	struct dentry *dir, *parent;
+	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(dev_name, NULL);
+	if (IS_ERR(parent)) {
+		pr_warn("%s: failed to create debugfs directory\n", dev_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", dev_name);
+		debugfs_remove_recursive(parent);
+		return;
+	}
+	fault_inj->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_fault_inject *fault_inject)
+{
+	/* remove debugfs directories */
+	debugfs_remove_recursive(fault_inject->parent);
+}
+
+void nvme_should_fail(struct request *req)
+{
+	struct gendisk *disk = req->q->disk;
+	struct nvme_fault_inject *fault_inject = NULL;
+	u16 status;
+
+	if (disk) {
+		struct nvme_ns *ns = disk->private_data;
+
+		if (ns)
+			fault_inject = &ns->fault_inject;
+		else
+			WARN_ONCE(1, "No namespace found for request\n");
+	} else {
+		fault_inject = &nvme_req(req)->ctrl->fault_inject;
+	}
+
+	if (fault_inject && should_fail(&fault_inject->attr, 1)) {
+		/* inject status code and DNR bit */
+		status = fault_inject->status;
+		if (fault_inject->dont_retry)
+			status |= NVME_SC_DNR;
+		nvme_req(req)->status =	status;
+	}
+}
+EXPORT_SYMBOL_GPL(nvme_should_fail);