diff options
Diffstat (limited to 'arch/loongarch/include/asm/kfence.h')
| -rw-r--r-- | arch/loongarch/include/asm/kfence.h | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/kfence.h b/arch/loongarch/include/asm/kfence.h new file mode 100644 index 000000000000..6c82aea1c993 --- /dev/null +++ b/arch/loongarch/include/asm/kfence.h @@ -0,0 +1,61 @@ +/* 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 <asm/pgtable.h> +#include <asm/tlb.h> + +static inline bool arch_kfence_init_pool(void) +{ + int err; + 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; + } + + 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(*pte)) + return false; + + if (protect) + set_pte(pte, __pte(pte_val(*pte) & ~(_PAGE_VALID | _PAGE_PRESENT))); + else + set_pte(pte, __pte(pte_val(*pte) | (_PAGE_VALID | _PAGE_PRESENT))); + + preempt_disable(); + local_flush_tlb_one(addr); + preempt_enable(); + + return true; +} + +#endif /* _ASM_LOONGARCH_KFENCE_H */ |