Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/*
2 * Copyright 2017, Anshuman Khandual, IBM Corp.
3 * Licensed under GPLv2.
4 *
5 * Works on architectures which support 128TB virtual
6 * address range and beyond.
7 */
8#include <stdio.h>
9#include <stdlib.h>
10#include <string.h>
11#include <unistd.h>
12#include <errno.h>
13#include <numaif.h>
14#include <sys/mman.h>
15#include <sys/time.h>
16
17/*
18 * Maximum address range mapped with a single mmap()
19 * call is little bit more than 16GB. Hence 16GB is
20 * chosen as the single chunk size for address space
21 * mapping.
22 */
23#define MAP_CHUNK_SIZE 17179869184UL /* 16GB */
24
25/*
26 * Address space till 128TB is mapped without any hint
27 * and is enabled by default. Address space beyond 128TB
28 * till 512TB is obtained by passing hint address as the
29 * first argument into mmap() system call.
30 *
31 * The process heap address space is divided into two
32 * different areas one below 128TB and one above 128TB
33 * till it reaches 512TB. One with size 128TB and the
34 * other being 384TB.
35 */
36#define NR_CHUNKS_128TB 8192UL /* Number of 16GB chunks for 128TB */
37#define NR_CHUNKS_384TB 24576UL /* Number of 16GB chunks for 384TB */
38
39#define ADDR_MARK_128TB (1UL << 47) /* First address beyond 128TB */
40
41static char *hind_addr(void)
42{
43 int bits = 48 + rand() % 15;
44
45 return (char *) (1UL << bits);
46}
47
48static int validate_addr(char *ptr, int high_addr)
49{
50 unsigned long addr = (unsigned long) ptr;
51
52 if (high_addr) {
53 if (addr < ADDR_MARK_128TB) {
54 printf("Bad address %lx\n", addr);
55 return 1;
56 }
57 return 0;
58 }
59
60 if (addr > ADDR_MARK_128TB) {
61 printf("Bad address %lx\n", addr);
62 return 1;
63 }
64 return 0;
65}
66
67static int validate_lower_address_hint(void)
68{
69 char *ptr;
70
71 ptr = mmap((void *) (1UL << 45), MAP_CHUNK_SIZE, PROT_READ |
72 PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
73
74 if (ptr == MAP_FAILED)
75 return 0;
76
77 return 1;
78}
79
80int main(int argc, char *argv[])
81{
82 char *ptr[NR_CHUNKS_128TB];
83 char *hptr[NR_CHUNKS_384TB];
84 char *hint;
85 unsigned long i, lchunks, hchunks;
86
87 for (i = 0; i < NR_CHUNKS_128TB; i++) {
88 ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE,
89 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
90
91 if (ptr[i] == MAP_FAILED) {
92 if (validate_lower_address_hint())
93 return 1;
94 break;
95 }
96
97 if (validate_addr(ptr[i], 0))
98 return 1;
99 }
100 lchunks = i;
101
102 for (i = 0; i < NR_CHUNKS_384TB; i++) {
103 hint = hind_addr();
104 hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE,
105 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
106
107 if (hptr[i] == MAP_FAILED)
108 break;
109
110 if (validate_addr(hptr[i], 1))
111 return 1;
112 }
113 hchunks = i;
114
115 for (i = 0; i < lchunks; i++)
116 munmap(ptr[i], MAP_CHUNK_SIZE);
117
118 for (i = 0; i < hchunks; i++)
119 munmap(hptr[i], MAP_CHUNK_SIZE);
120
121 return 0;
122}