1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * powerpc KFENCE support. 4 * 5 * Copyright (C) 2020 CS GROUP France 6 */ 7 8 #ifndef __ASM_POWERPC_KFENCE_H 9 #define __ASM_POWERPC_KFENCE_H 10 11 #include <linux/mm.h> 12 #include <asm/pgtable.h> 13 14 #ifdef CONFIG_PPC64_ELF_ABI_V1 15 #define ARCH_FUNC_PREFIX "." 16 #endif 17 18 static inline bool arch_kfence_init_pool(void) 19 { 20 return true; 21 } 22 23 #ifdef CONFIG_PPC64 24 static inline bool kfence_protect_page(unsigned long addr, bool protect) 25 { 26 struct page *page = virt_to_page((void *)addr); 27 28 __kernel_map_pages(page, 1, !protect); 29 30 return true; 31 } 32 #else 33 static inline bool kfence_protect_page(unsigned long addr, bool protect) 34 { 35 pte_t *kpte = virt_to_kpte(addr); 36 37 if (protect) { 38 pte_update(&init_mm, addr, kpte, _PAGE_PRESENT, 0, 0); 39 flush_tlb_kernel_range(addr, addr + PAGE_SIZE); 40 } else { 41 pte_update(&init_mm, addr, kpte, 0, _PAGE_PRESENT, 0); 42 } 43 44 return true; 45 } 46 #endif 47 48 #endif /* __ASM_POWERPC_KFENCE_H */ 49