| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * KFENCE support for LoongArch. |
| * |
| * Author: Enze Li <lienze@kylinos.cn> |
| * Copyright (C) 2022-2023 KylinSoft Corporation. |
| */ |
| |
| #ifndef _ASM_LOONGARCH_KFENCE_H |
| #define _ASM_LOONGARCH_KFENCE_H |
| |
| #include <linux/kfence.h> |
| #include <linux/vmalloc.h> |
| #include <asm/pgtable.h> |
| #include <asm/tlb.h> |
| |
| static inline bool arch_kfence_init_pool(void) |
| { |
| int err; |
| char *kaddr, *vaddr; |
| char *kfence_pool = __kfence_pool; |
| struct vm_struct *area; |
| |
| area = __get_vm_area_caller(KFENCE_POOL_SIZE, VM_IOREMAP, |
| KFENCE_AREA_START, KFENCE_AREA_END, |
| __builtin_return_address(0)); |
| if (!area) |
| return false; |
| |
| __kfence_pool = (char *)area->addr; |
| err = ioremap_page_range((unsigned long)__kfence_pool, |
| (unsigned long)__kfence_pool + KFENCE_POOL_SIZE, |
| virt_to_phys((void *)kfence_pool), PAGE_KERNEL); |
| if (err) { |
| free_vm_area(area); |
| __kfence_pool = kfence_pool; |
| return false; |
| } |
| |
| kaddr = kfence_pool; |
| vaddr = __kfence_pool; |
| while (kaddr < kfence_pool + KFENCE_POOL_SIZE) { |
| set_page_address(virt_to_page(kaddr), vaddr); |
| kaddr += PAGE_SIZE; |
| vaddr += PAGE_SIZE; |
| } |
| |
| return true; |
| } |
| |
| /* Protect the given page and flush TLB. */ |
| static inline bool kfence_protect_page(unsigned long addr, bool protect) |
| { |
| pte_t *pte = virt_to_kpte(addr); |
| |
| if (WARN_ON(!pte) || pte_none(ptep_get(pte))) |
| return false; |
| |
| if (protect) |
| set_pte(pte, __pte(pte_val(ptep_get(pte)) & ~(_PAGE_VALID | _PAGE_PRESENT))); |
| else |
| set_pte(pte, __pte(pte_val(ptep_get(pte)) | (_PAGE_VALID | _PAGE_PRESENT))); |
| |
| preempt_disable(); |
| local_flush_tlb_one(addr); |
| preempt_enable(); |
| |
| return true; |
| } |
| |
| #endif /* _ASM_LOONGARCH_KFENCE_H */ |
