1 /*
2 * This is a reproducer copied from one of LKML patch submission,
3 * which subject is
4 *
5 * [PATCH] mlock: revert the optimization for dirtying pages and triggering writeback.
6 *
7 * "In 5ecfda0, we do some optimization in mlock, but it causes
8 * a very basic test case(attached below) of mlock to fail. So
9 * this patch revert it with some tiny modification so that it
10 * apply successfully with the lastest 38-rc2 kernel."
11 *
12 * Copyright (C) 2010 Red Hat, Inc.
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of version 2 of the GNU General Public
15 * License as published by the Free Software Foundation.
16 *
17 * This program is distributed in the hope that it would be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * Further, this software is distributed without any warranty that it
22 * is free of the rightful claim of any third person regarding
23 * infringement or the like. Any license provided herein, whether
24 * implied or otherwise, applies only to this software file. Patent
25 * licenses, if any, provided herein do not apply to combinations of
26 * this program with other software, or any other product whatsoever.
27 *
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write the Free Software
30 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
31 * 02110-1301, USA.
32 */
33 #include "test.h"
34 #include "safe_macros.h"
35 #include "config.h"
36
37 char *TCID = "mlock04";
38 int TST_TOTAL = 1;
39
40 #include <sys/mman.h>
41 #include <stdio.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <unistd.h>
47 #include <sys/types.h>
48
49 int fd, file_len = 40960;
50 char *testfile = "test_mlock";
51
52 static void setup(void);
53 static void cleanup(void);
54
main(void)55 int main(void)
56 {
57 char *buf;
58 int lc;
59
60 setup();
61
62 for (lc = 0; TEST_LOOPING(lc); lc++) {
63 buf = mmap(NULL, file_len, PROT_WRITE, MAP_SHARED, fd, 0);
64
65 if (buf == MAP_FAILED)
66 tst_brkm(TBROK | TERRNO, cleanup, "mmap");
67
68 if (mlock(buf, file_len) == -1)
69 tst_brkm(TBROK | TERRNO, cleanup, "mlock");
70
71 tst_resm(TINFO, "locked %d bytes from %p", file_len, buf);
72
73 if (munlock(buf, file_len) == -1)
74 tst_brkm(TBROK | TERRNO, cleanup, "munlock");
75
76 SAFE_MUNMAP(cleanup, buf, file_len);
77 }
78
79 tst_resm(TPASS, "test succeeded.");
80
81 cleanup();
82
83 tst_exit();
84 }
85
setup(void)86 static void setup(void)
87 {
88 tst_tmpdir();
89
90 fd = SAFE_OPEN(cleanup, testfile, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR);
91
92 SAFE_FTRUNCATE(cleanup, fd, file_len);
93
94 TEST_PAUSE;
95 }
96
cleanup(void)97 static void cleanup(void)
98 {
99 close(fd);
100
101 tst_rmdir();
102 }
103