1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 2013 FNST, DAN LI <li.dan@cn.fujitsu.com>
4 */
5
6 /*
7 * Test Description:
8 * Verify MAP_POPULATE works fine.
9 * "For a file mapping, this causes read-ahead on the file.
10 * Later accesses to the mapping will not be blocked by page faults"
11 *
12 * Expected Result:
13 * mmap() with MAP_POPULATE should succeed returning the address of the
14 * mapped region and this file has been read into RAM, so pages should
15 * be present.
16 */
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <sys/types.h>
20 #include <errno.h>
21 #include <unistd.h>
22 #include <fcntl.h>
23 #include <string.h>
24 #include <signal.h>
25 #include <stdint.h>
26 #include <sys/stat.h>
27 #include <sys/mman.h>
28 #include <sys/shm.h>
29
30 #include "tst_test.h"
31
32 #define TEMPFILE "mmapfile"
33 #define PATHLEN 256
34 #define MMAPSIZE (1UL<<20)
35
36 static int fildes;
37 static char *addr;
38
page_check(void)39 static void page_check(void)
40 {
41 int i = 1;
42 int flag = 0;
43 int pm;
44 int num_pages;
45 long index;
46 off_t offset;
47 size_t page_sz;
48 uint64_t pagemap;
49 unsigned long vmstart;
50
51 vmstart = (unsigned long)addr;
52 page_sz = getpagesize();
53
54 num_pages = MMAPSIZE / page_sz;
55 index = (vmstart / page_sz) * sizeof(uint64_t);
56
57 pm = open("/proc/self/pagemap", O_RDONLY);
58 if (pm == -1) {
59 if ((errno == EPERM) && (geteuid() != 0)) {
60 tst_res(TCONF | TERRNO,
61 "don't have permission to open dev pagemap");
62 return;
63 } else {
64 tst_brk(TFAIL | TERRNO, "pen dev pagemap failed");
65 }
66 }
67
68 offset = SAFE_LSEEK(pm, index, SEEK_SET);
69 if (offset != index)
70 tst_brk(TFAIL | TERRNO, "Reposition offset failed");
71
72 while (i <= num_pages) {
73 SAFE_READ(1, pm, &pagemap, sizeof(uint64_t));
74
75 /*
76 * Check if the page is present.
77 */
78 if (!(pagemap & (1ULL<<63))) {
79 tst_res(TINFO, "The %dth page addressed at %lX is not "
80 "present", i, vmstart + i * page_sz);
81 flag = 1;
82 }
83
84 i++;
85 }
86
87 close(pm);
88
89 if (!flag)
90 tst_res(TINFO, "All pages are present");
91 }
92
verify_mmap(void)93 void verify_mmap(void)
94 {
95 unsigned int i;
96
97 addr = mmap(NULL, MMAPSIZE, PROT_READ | PROT_WRITE,
98 MAP_PRIVATE | MAP_POPULATE, fildes, 0);
99
100 if (addr == MAP_FAILED) {
101 tst_res(TFAIL | TERRNO, "mmap of %s failed", TEMPFILE);
102 return;
103 }
104
105 page_check();
106
107 for (i = 0; i < MMAPSIZE; i++) {
108 if (addr[i]) {
109 tst_res(TFAIL, "Non-zero byte at offset %i", i);
110 goto unmap;
111 }
112 }
113
114 tst_res(TPASS, "File mapped properly");
115
116 unmap:
117 SAFE_MUNMAP(addr, MMAPSIZE);
118 }
119
setup(void)120 static void setup(void)
121 {
122 fildes = SAFE_OPEN(TEMPFILE, O_RDWR | O_CREAT, 0766);
123
124 SAFE_FTRUNCATE(fildes, MMAPSIZE);
125 }
126
cleanup(void)127 static void cleanup(void)
128 {
129 if (fildes > 0)
130 SAFE_CLOSE(fildes);
131 }
132
133 static struct tst_test test = {
134 .setup = setup,
135 .cleanup = cleanup,
136 .test_all = verify_mmap,
137 .needs_tmpdir = 1,
138 .min_kver = "2.6.25",
139 };
140