162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */ 262306a36Sopenharmony_ci/* 362306a36Sopenharmony_ci * powerpc KFENCE support. 462306a36Sopenharmony_ci * 562306a36Sopenharmony_ci * Copyright (C) 2020 CS GROUP France 662306a36Sopenharmony_ci */ 762306a36Sopenharmony_ci 862306a36Sopenharmony_ci#ifndef __ASM_POWERPC_KFENCE_H 962306a36Sopenharmony_ci#define __ASM_POWERPC_KFENCE_H 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_ci#include <linux/mm.h> 1262306a36Sopenharmony_ci#include <asm/pgtable.h> 1362306a36Sopenharmony_ci 1462306a36Sopenharmony_ci#ifdef CONFIG_PPC64_ELF_ABI_V1 1562306a36Sopenharmony_ci#define ARCH_FUNC_PREFIX "." 1662306a36Sopenharmony_ci#endif 1762306a36Sopenharmony_ci 1862306a36Sopenharmony_cistatic inline bool arch_kfence_init_pool(void) 1962306a36Sopenharmony_ci{ 2062306a36Sopenharmony_ci return true; 2162306a36Sopenharmony_ci} 2262306a36Sopenharmony_ci 2362306a36Sopenharmony_ci#ifdef CONFIG_PPC64 2462306a36Sopenharmony_cistatic inline bool kfence_protect_page(unsigned long addr, bool protect) 2562306a36Sopenharmony_ci{ 2662306a36Sopenharmony_ci struct page *page = virt_to_page((void *)addr); 2762306a36Sopenharmony_ci 2862306a36Sopenharmony_ci __kernel_map_pages(page, 1, !protect); 2962306a36Sopenharmony_ci 3062306a36Sopenharmony_ci return true; 3162306a36Sopenharmony_ci} 3262306a36Sopenharmony_ci#else 3362306a36Sopenharmony_cistatic inline bool kfence_protect_page(unsigned long addr, bool protect) 3462306a36Sopenharmony_ci{ 3562306a36Sopenharmony_ci pte_t *kpte = virt_to_kpte(addr); 3662306a36Sopenharmony_ci 3762306a36Sopenharmony_ci if (protect) { 3862306a36Sopenharmony_ci pte_update(&init_mm, addr, kpte, _PAGE_PRESENT, 0, 0); 3962306a36Sopenharmony_ci flush_tlb_kernel_range(addr, addr + PAGE_SIZE); 4062306a36Sopenharmony_ci } else { 4162306a36Sopenharmony_ci pte_update(&init_mm, addr, kpte, 0, _PAGE_PRESENT, 0); 4262306a36Sopenharmony_ci } 4362306a36Sopenharmony_ci 4462306a36Sopenharmony_ci return true; 4562306a36Sopenharmony_ci} 4662306a36Sopenharmony_ci#endif 4762306a36Sopenharmony_ci 4862306a36Sopenharmony_ci#endif /* __ASM_POWERPC_KFENCE_H */ 49