arch/powerpc/mm/kasan/book3s_32.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #define DISABLE_BRANCH_PROFILING
   4
   5 #include <linux/kasan.h>
   6 #include <linux/memblock.h>
   7 #include <mm/mmu_decl.h>
   8
   9 int __init kasan_init_region(void *start, size_t size)
  10 {
  11         unsigned long k_start = (unsigned long)kasan_mem_to_shadow(start);
  12         unsigned long k_end = (unsigned long)kasan_mem_to_shadow(start + size);
  13         unsigned long k_nobat = k_start;
  14         unsigned long k_cur;
  15         phys_addr_t phys;
  16         int ret;
  17
  18         while (k_nobat < k_end) {
  19                 unsigned int k_size = bat_block_size(k_nobat, k_end);
  20                 int idx = find_free_bat();
  21
  22                 if (idx == -1)
  23                         break;
  24                 if (k_size < SZ_128K)
  25                         break;
  26                 phys = memblock_phys_alloc_range(k_size, k_size, 0,
  27                                                  MEMBLOCK_ALLOC_ANYWHERE);
  28                 if (!phys)
  29                         break;
  30
  31                 setbat(idx, k_nobat, phys, k_size, PAGE_KERNEL);
  32                 k_nobat += k_size;
  33         }
  34         if (k_nobat != k_start)
  35                 update_bats();
  36
  37         if (k_nobat < k_end) {
  38                 phys = memblock_phys_alloc_range(k_end - k_nobat, PAGE_SIZE, 0,
  39                                                  MEMBLOCK_ALLOC_ANYWHERE);
  40                 if (!phys)
  41                         return -ENOMEM;
  42         }
  43
  44         ret = kasan_init_shadow_page_tables(k_start, k_end);
  45         if (ret)
  46                 return ret;
  47
  48         kasan_update_early_region(k_start, k_nobat, __pte(0));
  49
  50         for (k_cur = k_nobat; k_cur < k_end; k_cur += PAGE_SIZE) {
  51                 pmd_t *pmd = pmd_off_k(k_cur);
  52                 pte_t pte = pfn_pte(PHYS_PFN(phys + k_cur - k_nobat), PAGE_KERNEL);
  53
  54                 __set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0);
  55         }
  56         flush_tlb_kernel_range(k_start, k_end);
  57         memset(kasan_mem_to_shadow(start), 0, k_end - k_start);
  58
  59         return 0;
  60 }