1 /* 2 * Copyright (c) 2002, Intel Corporation. All rights reserved. 3 * Copyright (c) 2012, Cyril Hrubis <chrubis (at) 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 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
