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
9int __init kasan_init_region(void *start, size_t size)
10{
11 unsigned long k_start = (unsigned long)kasan_mem_to_shadow(addr: start);
12 unsigned long k_end = (unsigned long)kasan_mem_to_shadow(addr: 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(size: k_size, align: k_size, start: 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(size: k_end - k_nobat, PAGE_SIZE, start: 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(val: 0));
49
50 for (k_cur = k_nobat; k_cur < k_end; k_cur += PAGE_SIZE) {
51 pmd_t *pmd = pmd_off_k(va: 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, address: k_cur), pte, 0);
55 }
56 flush_tlb_kernel_range(start: k_start, end: k_end);
57 memset(kasan_mem_to_shadow(start), 0, k_end - k_start);
58
59 return 0;
60}
61

source code of linux/arch/powerpc/mm/kasan/book3s_32.c