1 files changed, 48 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/kfence.h b/arch/powerpc/include/asm/kfence.h
new file mode 100644
index 000000000000..424ceef82ae6
--- /dev/null
+++ b/arch/powerpc/include/asm/kfence.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * powerpc KFENCE support.
+ *
+ * Copyright (C) 2020 CS GROUP France
+ */
+
+#ifndef __ASM_POWERPC_KFENCE_H
+#define __ASM_POWERPC_KFENCE_H
+
+#include <linux/mm.h>
+#include <asm/pgtable.h>
+
+#ifdef CONFIG_PPC64_ELF_ABI_V1
+#define ARCH_FUNC_PREFIX "."
+#endif
+
+static inline bool arch_kfence_init_pool(void)
+{
+	return true;
+}
+
+#ifdef CONFIG_PPC64
+static inline bool kfence_protect_page(unsigned long addr, bool protect)
+{
+	struct page *page = virt_to_page((void *)addr);
+
+	__kernel_map_pages(page, 1, !protect);
+
+	return true;
+}
+#else
+static inline bool kfence_protect_page(unsigned long addr, bool protect)
+{
+	pte_t *kpte = virt_to_kpte(addr);
+
+	if (protect) {
+		pte_update(&init_mm, addr, kpte, _PAGE_PRESENT, 0, 0);
+		flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+	} else {
+		pte_update(&init_mm, addr, kpte, 0, _PAGE_PRESENT, 0);
+	}
+
+	return true;
+}
+#endif
+
+#endif /* __ASM_POWERPC_KFENCE_H */