1/* 2 * Copyright (c) 2002, Intel Corporation. All rights reserved. 3 * This file is licensed under the GPL license. For the full content 4 * of this license, see the COPYING file at the top level of this 5 * source tree. 6 * 7 * Implementation performs mapping operations over whole pages. 8 * Thus, while the argument len 9 * need not meet a size or alignment constraint, 10 * the implementation shall include, in any mapping 11 * operation, any partial page specified by the range [pa,pa+len). 12 * The system shall always zero-fill any partial page at the end of an object. 13 * Further, the system shall never write out any modified portions of 14 * the last page of an object which are beyond its end. 15 * 16 * Test step: 17 * 1. Create a process, in this process: 18 a. map a shared memory object with size of 1/2 * page_size, 19 * set len = 1/2 * page_size 20 * b. Read the partial page beyond the object size. 21 * Make sure the partial page is zero-filled; 22 * c. Modify a byte in the partial page, then un-map the and close the 23 * file descriptor. 24 * 2. Wait for the child proces to exit, then 25 * Map the shared memory object again, 26 * read the byte from the position modified at step 1-c and check. 27 */ 28 29#define _XOPEN_SOURCE 600 30 31#include <pthread.h> 32#include <stdio.h> 33#include <stdlib.h> 34#include <unistd.h> 35#include <sys/mman.h> 36#include <sys/types.h> 37#include <sys/stat.h> 38#include <sys/wait.h> 39#include <fcntl.h> 40#include <string.h> 41#include <errno.h> 42#include "posixtest.h" 43 44#define TNAME "mmap/11-5.c" 45 46int main() 47{ 48 char tmpfname[256]; 49 long page_size; 50 long total_size; 51 52 void *pa = NULL, *pa_2 = NULL; 53 void *addr = NULL; 54 size_t len; 55 int flag; 56 int fd, fd_2; 57 off_t off = 0; 58 int prot; 59 60 pid_t child; 61 char *ch = NULL, *ch_2 = NULL; 62 int exit_val; 63 64 page_size = sysconf(_SC_PAGE_SIZE); 65 66 /* Size of the file to be mapped */ 67 total_size = page_size / 2; 68 69 /* mmap will create a partial page */ 70 len = page_size / 2; 71 72 snprintf(tmpfname, sizeof(tmpfname), "pts_mmap_11_5_%ld", 73 (long)getpid()); 74 child = fork(); 75 if (child == 0) 76 { 77 /* Create shared object */ 78 shm_unlink(tmpfname); 79 fd = shm_open(tmpfname, O_RDWR|O_CREAT|O_EXCL, S_IRUSR|S_IWUSR); 80 if(fd == -1) 81 { 82 printf(TNAME " Error at shm_open(): %s\n", strerror(errno)); 83 return PTS_UNRESOLVED; 84 } 85 if(ftruncate(fd, total_size) == -1) { 86 printf(TNAME " Error at ftruncate(): %s\n", strerror(errno)); 87 return PTS_UNRESOLVED; 88 } 89 90 prot = PROT_READ | PROT_WRITE; 91 flag = MAP_SHARED; 92 off = 0; 93 pa = mmap(addr, len, prot, flag, fd, off); 94 if (pa == MAP_FAILED) 95 { 96 printf("Test FAIL: " TNAME " Error at mmap(): %s\n", 97 strerror(errno)); 98 return PTS_FAIL; 99 } 100 /* Check the patial page is ZERO filled */ 101 ch = pa + len + 1; 102 if (*ch != 0) 103 { 104 printf("Test Fail: " TNAME " The partial page at the end of an object " 105 "is not zero-filled\n"); 106 return PTS_FAIL; 107 } 108 109 /* Write the partial page */ 110 *ch = 'b'; 111 munmap (pa, len); 112 close (fd); 113 return PTS_PASS; 114 } 115 wait(&exit_val); 116 if (!(WIFEXITED(exit_val) && 117 (WEXITSTATUS(exit_val) == PTS_PASS))) 118 { 119 shm_unlink(tmpfname); 120 return PTS_FAIL; 121 } 122 123 fd_2 = shm_open(tmpfname, O_RDWR, 0); 124 shm_unlink(tmpfname); 125 126 prot = PROT_READ | PROT_WRITE; 127 flag = MAP_SHARED; 128 off = 0; 129 pa_2 = mmap(addr, len, prot, flag, fd_2, off); 130 if (pa_2 == MAP_FAILED) 131 { 132 printf("Test FAIL: " TNAME " Error at 2nd mmap(): %s\n", 133 strerror(errno)); 134 exit(PTS_FAIL); 135 } 136 137 ch_2 = pa_2 + len + 1; 138 if (*ch_2 == 'b') 139 { 140 printf("Test Fail: " TNAME " Modification of the partial page " 141 "at the end of an object is written out\n"); 142 exit(PTS_FAIL); 143 } 144 close (fd_2); 145 munmap (pa_2, len); 146 printf("Test Passed\n"); 147 return PTS_PASS; 148} 149