LXR linux/arch/parisc/mm/fixmap.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * fixmaps for parisc
   4 *
   5 * Copyright (c) 2019 Sven Schnelle <svens@stackframe.org>
   6 */
   7
   8#include <linux/kprobes.h>
   9#include <linux/mm.h>
  10#include <asm/cacheflush.h>
  11#include <asm/fixmap.h>
  12
  13void notrace set_fixmap(enum fixed_addresses idx, phys_addr_t phys)
  14{
  15        unsigned long vaddr = __fix_to_virt(idx);
  16        pgd_t *pgd = pgd_offset_k(vaddr);
  17        p4d_t *p4d = p4d_offset(pgd, vaddr);
  18        pud_t *pud = pud_offset(p4d, vaddr);
  19        pmd_t *pmd = pmd_offset(pud, vaddr);
  20        pte_t *pte;
  21
  22        if (pmd_none(*pmd))
  23                pmd = pmd_alloc(NULL, pud, vaddr);
  24
  25        pte = pte_offset_kernel(pmd, vaddr);
  26        if (pte_none(*pte))
  27                pte = pte_alloc_kernel(pmd, vaddr);
  28
  29        set_pte_at(&init_mm, vaddr, pte, __mk_pte(phys, PAGE_KERNEL_RWX));
  30        flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
  31}
  32
  33void notrace clear_fixmap(enum fixed_addresses idx)
  34{
  35        unsigned long vaddr = __fix_to_virt(idx);
  36        pte_t *pte = virt_to_kpte(vaddr);
  37
  38        if (WARN_ON(pte_none(*pte)))
  39                return;
  40
  41        pte_clear(&init_mm, vaddr, pte);
  42
  43        flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
  44}
  45