LoongArch: Add memory management

Add memory management support for LoongArch, including: cache and tlb
management, page fault handling and ioremap/mmap support.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/loongarch/mm/extable.c b/arch/loongarch/mm/extable.c
new file mode 100644
index 000000000000..bc20988f2b87
--- /dev/null
+++ b/arch/loongarch/mm/extable.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+#include <linux/extable.h>
+#include <linux/spinlock.h>
+#include <asm/branch.h>
+#include <linux/uaccess.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+	const struct exception_table_entry *fixup;
+
+	fixup = search_exception_tables(exception_era(regs));
+	if (fixup) {
+		regs->csr_era = fixup->fixup;
+
+		return 1;
+	}
+
+	return 0;
+}