1 files changed, 82 insertions, 0 deletions
diff --git a/drivers/ufs/core/ufs-fault-injection.c b/drivers/ufs/core/ufs-fault-injection.c
new file mode 100644
index 000000000000..55db38e75cc4
--- /dev/null
+++ b/drivers/ufs/core/ufs-fault-injection.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/kconfig.h>
+#include <linux/types.h>
+#include <linux/fault-inject.h>
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <ufs/ufshcd.h>
+#include "ufs-fault-injection.h"
+
+static int ufs_fault_get(char *buffer, const struct kernel_param *kp);
+static int ufs_fault_set(const char *val, const struct kernel_param *kp);
+
+static const struct kernel_param_ops ufs_fault_ops = {
+	.get = ufs_fault_get,
+	.set = ufs_fault_set,
+};
+
+enum { FAULT_INJ_STR_SIZE = 80 };
+
+/*
+ * For more details about fault injection, please refer to
+ * Documentation/fault-injection/fault-injection.rst.
+ */
+static char g_trigger_eh_str[FAULT_INJ_STR_SIZE];
+module_param_cb(trigger_eh, &ufs_fault_ops, g_trigger_eh_str, 0644);
+MODULE_PARM_DESC(trigger_eh,
+	"Fault injection. trigger_eh=<interval>,<probability>,<space>,<times>");
+static DECLARE_FAULT_ATTR(ufs_trigger_eh_attr);
+
+static char g_timeout_str[FAULT_INJ_STR_SIZE];
+module_param_cb(timeout, &ufs_fault_ops, g_timeout_str, 0644);
+MODULE_PARM_DESC(timeout,
+	"Fault injection. timeout=<interval>,<probability>,<space>,<times>");
+static DECLARE_FAULT_ATTR(ufs_timeout_attr);
+
+static int ufs_fault_get(char *buffer, const struct kernel_param *kp)
+{
+	const char *fault_str = kp->arg;
+
+	return sysfs_emit(buffer, "%s\n", fault_str);
+}
+
+static int ufs_fault_set(const char *val, const struct kernel_param *kp)
+{
+	struct fault_attr *attr = NULL;
+
+	if (kp->arg == g_trigger_eh_str)
+		attr = &ufs_trigger_eh_attr;
+	else if (kp->arg == g_timeout_str)
+		attr = &ufs_timeout_attr;
+
+	if (WARN_ON_ONCE(!attr))
+		return -EINVAL;
+
+	if (!setup_fault_attr(attr, (char *)val))
+		return -EINVAL;
+
+	strscpy(kp->arg, val, FAULT_INJ_STR_SIZE);
+
+	return 0;
+}
+
+void ufs_fault_inject_hba_init(struct ufs_hba *hba)
+{
+	hba->trigger_eh_attr = ufs_trigger_eh_attr;
+	hba->timeout_attr = ufs_timeout_attr;
+#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
+	fault_create_debugfs_attr("trigger_eh_inject", hba->debugfs_root, &hba->trigger_eh_attr);
+	fault_create_debugfs_attr("timeout_inject", hba->debugfs_root, &hba->timeout_attr);
+#endif
+}
+
+bool ufs_trigger_eh(struct ufs_hba *hba)
+{
+	return should_fail(&hba->trigger_eh_attr, 1);
+}
+
+bool ufs_fail_completion(struct ufs_hba *hba)
+{
+	return should_fail(&hba->timeout_attr, 1);
+}