1 /*
2 * Copyright (c) 2002, Intel Corporation. All rights reserved.
3 * Copyright (c) 2012, Cyril Hrubis <chrubis@suse.cz>
4 *
5 * This file is licensed under the GPL license. For the full content
6 * of this license, see the COPYING file at the top level of this
7 * source tree.
8 *
9 * Implementation performs mapping operations over whole pages.
10 * Thus, while the argument len
11 * need not meet a size or alignment constraint,
12 * the implementation shall include, in any mapping
13 * operation, any partial page specified by the range [pa,pa+len).
14 * The system shall always zero-fill any partial page at the end of an object.
15 * Further, the system shall never write out any modified portions of
16 * the last page of an object which are beyond its end.
17 *
18 * Test Steps:
19 * 1. Create a process, in this process:
20 * a. map a shared memory object with size of 1/2 * page_size,
21 * set len = 1/2 * page_size
22 * b. Read the partial page beyond the object size.
23 * Make sure the partial page is zero-filled;
24 * c. Modify a byte in the partial page, then un-map the and close the
25 * file descriptor.
26 * 2. Wait for the child proces to exit, then read the file using read()
27 * and check that change wasn't written.
28 */
29
30
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <unistd.h>
34 #include <sys/mman.h>
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 #include <sys/wait.h>
38 #include <fcntl.h>
39 #include <string.h>
40 #include <errno.h>
41 #include "posixtest.h"
42
main(void)43 int main(void)
44 {
45 char tmpfname[256];
46 long page_size;
47
48 char *pa, ch;
49 ssize_t len;
50 int fd;
51
52 pid_t child;
53 int i, exit_val, ret, size;
54
55 page_size = sysconf(_SC_PAGE_SIZE);
56
57 /* mmap will create a partial page */
58 len = page_size / 2;
59
60 snprintf(tmpfname, sizeof(tmpfname), "pts_mmap_11_5_%d", getpid());
61 child = fork();
62 switch (child) {
63 case 0:
64 /* Create shared object */
65 shm_unlink(tmpfname);
66 fd = shm_open(tmpfname, O_RDWR | O_CREAT | O_EXCL,
67 S_IRUSR | S_IWUSR);
68 if (fd == -1) {
69 printf("Error at shm_open(): %s\n", strerror(errno));
70 return PTS_UNRESOLVED;
71 }
72 if (ftruncate(fd, len) == -1) {
73 printf("Error at ftruncate(): %s\n", strerror(errno));
74 return PTS_UNRESOLVED;
75 }
76
77 pa = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
78 if (pa == MAP_FAILED) {
79 printf("Error at mmap(): %s\n", strerror(errno));
80 return PTS_FAIL;
81 }
82
83 /* Check the patial page is ZERO filled */
84 for (i = len; i < page_size; i++)
85 if (pa[i] != 0) {
86 printf("Test FAILED: The partial page at the "
87 "end of an object is not zero-filled\n");
88 return PTS_FAIL;
89 }
90
91 /* Write the partial page */
92 pa[len + 1] = 'b';
93 munmap(pa, len);
94 close(fd);
95 return PTS_PASS;
96 case -1:
97 printf("Error at fork(): %s\n", strerror(errno));
98 return PTS_UNRESOLVED;
99 default:
100 break;
101 }
102
103 wait(&exit_val);
104 if (!(WIFEXITED(exit_val) && (WEXITSTATUS(exit_val) == PTS_PASS))) {
105 unlink(tmpfname);
106
107 if (WIFEXITED(exit_val))
108 return WEXITSTATUS(exit_val);
109
110 printf("Child exited abnormally\n");
111 return PTS_UNRESOLVED;
112 }
113
114 fd = shm_open(tmpfname, O_RDWR, 0);
115 shm_unlink(tmpfname);
116
117 size = 0;
118
119 while ((ret = read(fd, &ch, 1)) == 1) {
120
121 if (ch != 0) {
122 printf("File is not zeroed\n");
123 return PTS_FAIL;
124 }
125
126 size += ret;
127 }
128
129 if (ret == -1) {
130 printf("Error at read(): %s\n", strerror(errno));
131 return PTS_UNRESOLVED;
132 }
133
134 if (size != len) {
135 printf("File has wrong size\n");
136 return PTS_UNRESOLVED;
137 }
138
139 close(fd);
140
141 printf("Test PASSED\n");
142 return PTS_PASS;
143 }
144