1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 #ifndef _ASM_RISCV_KFENCE_H 4 #define _ASM_RISCV_KFENCE_H 5 6 #include <linux/kfence.h> 7 #include <linux/pfn.h> 8 #include <asm-generic/pgalloc.h> 9 #include <asm/cacheflush.h> 10 #include <asm/pgtable.h> 11 12 static inline bool arch_kfence_init_pool(void) 13 { 14 return true; 15 } 16 17 static inline bool kfence_protect_page(unsigned long addr, bool protect) 18 { 19 pte_t *pte = virt_to_kpte(addr); 20 21 if (protect) { 22 set_pte(pte, __pte(pte_val(ptep_get(pte)) & ~_PAGE_PRESENT)); 23 } else { 24 set_pte(pte, __pte(pte_val(ptep_get(pte)) | _PAGE_PRESENT)); 25 mark_new_valid_map(); 26 } 27 28 preempt_disable(); 29 local_flush_tlb_kernel_range(addr, addr + PAGE_SIZE); 30 preempt_enable(); 31 32 return true; 33 } 34 35 #endif /* _ASM_RISCV_KFENCE_H */ 36