1 /* 2 * This file and its contents are supplied under the terms of the 3 * Common Development and Distribution License ("CDDL"), version 1.0. 4 * You may only use this file in accordance with the terms of version 5 * 1.0 of the CDDL. 6 * 7 * A full copy of the text of the CDDL should have accompanied this 8 * source. A copy of the CDDL is also available via the Internet at 9 * http://www.illumos.org/license/CDDL. 10 */ 11 12 /* 13 * Copyright 2012 Jilin Xpd <jilinxpd@gmail.com> 14 * Copyright 2018 Nexenta Systems, Inc. 15 */ 16 17 /* 18 * Copy a file from src to dest, using mmap to copy the data, 19 * with either contiguous or discontiguous mappings. 20 * (Jilin calls discontiguous "discrete" below.) 21 */ 22 23 #include <sys/mman.h> 24 #include <sys/types.h> 25 #include <sys/stat.h> 26 #include <limits.h> 27 #include <fcntl.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <unistd.h> 31 #include <string.h> 32 #include <errno.h> 33 34 void 35 usage(void) 36 { 37 fprintf(stderr, 38 "usage: cp_mmap -t {d|c} -f <srcfile> <desfile>\n"); 39 exit(1); 40 } 41 42 int 43 main(int argc, char **argv) 44 { 45 struct stat sb; 46 char *src_addr, *des_addr; 47 char *src_file = NULL, *des_file = NULL; 48 off_t offset; 49 size_t filesize; 50 size_t blksize; 51 size_t pagesize; 52 size_t len; 53 size_t numblks; 54 int src_fid, des_fid; 55 int mret = 0; 56 size_t i; 57 size_t stride; 58 boolean_t discrete = B_FALSE; /* discontiguous mappings */ 59 60 /* 61 * parse arguments 62 * Not getopt because -f has two optargs 63 */ 64 if (argc != 6) 65 usage(); 66 67 for (i = 1; i < argc; ) { 68 switch (argv[i][1]) { 69 case 't': /* copy type */ 70 i++; 71 discrete = (argv[i][0] == 'd'); 72 i++; 73 break; 74 case 'f': /* src file and des file */ 75 i++; 76 src_file = argv[i]; 77 i++; 78 des_file = argv[i]; 79 i++; 80 break; 81 default: 82 usage(); 83 break; 84 } 85 } 86 87 pagesize = sysconf(_SC_PAGESIZE); /* mmap one page each time */ 88 if (pagesize < 4096) { 89 fprintf(stderr, "sysconf error=%d\n", errno); 90 return (1); 91 } 92 if (discrete) { 93 /* 94 * Use discontiguous mappings, and only mmap 95 * one page each time 96 */ 97 blksize = pagesize; 98 stride = 3; 99 } else { 100 /* will do contiguous mmap */ 101 blksize = 64 * 1024 * 1024; /* mmap a block each time */ 102 stride = 1; 103 } 104 105 /* source file */ 106 src_fid = open(src_file, O_RDONLY); 107 if (src_fid == -1) { 108 fprintf(stderr, "open %s error=%d\n", src_file, errno); 109 return (1); 110 } 111 /* destination file */ 112 des_fid = open(des_file, O_RDWR | O_CREAT | O_TRUNC, 113 S_IRUSR | S_IWUSR | S_IROTH | S_IWOTH); 114 if (des_fid == -1) { 115 fprintf(stderr, "open %s error=%d\n", des_file, errno); 116 mret = 1; 117 goto exit3; 118 } 119 120 /* get src file size */ 121 if (fstat(src_fid, &sb) == -1) { 122 fprintf(stderr, "fstat %s error=%d\n", src_file, errno); 123 mret = 1; 124 goto exit2; 125 } 126 filesize = sb.st_size; 127 if (filesize < pagesize) { 128 fprintf(stderr, "src file size < %d\n", (int)pagesize); 129 mret = 1; 130 goto exit2; 131 } 132 133 /* extend des file */ 134 if (ftruncate(des_fid, filesize) == -1) { 135 fprintf(stderr, "ftrunc %s error=%d\n", des_file, errno); 136 mret = 1; 137 goto exit2; 138 } 139 140 /* copy data */ 141 numblks = (filesize + blksize - 1) / blksize; 142 for (i = 0; i < stride * numblks && mret == 0; i += stride) { 143 144 offset = (i % numblks) * blksize; 145 if (offset + blksize > filesize) 146 len = filesize - offset; 147 else 148 len = blksize; 149 150 /* map file */ 151 src_addr = mmap(NULL, len, PROT_READ, MAP_SHARED, 152 src_fid, offset); 153 if (src_addr == MAP_FAILED) { 154 fprintf(stderr, "mmap %s error=%d\n", src_file, errno); 155 mret = 1; 156 break; 157 } 158 des_addr = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, 159 des_fid, offset); 160 if (des_addr == MAP_FAILED) { 161 fprintf(stderr, "mmap %s error=%d\n", des_file, errno); 162 mret = 1; 163 goto exit1; 164 } 165 166 /* cp data from src addr to des addr */ 167 memcpy(des_addr, src_addr, len); 168 /* sync mapped pages to file */ 169 if (msync(des_addr, len, MS_SYNC) == -1) { 170 fprintf(stderr, "msync %s error=%d\n", des_file, errno); 171 mret = 1; 172 } 173 174 /* unmap file */ 175 if (munmap(des_addr, len) == -1) { 176 fprintf(stderr, "munmap %s error=%d\n", 177 des_file, errno); 178 mret = 1; 179 } 180 exit1: 181 if (munmap(src_addr, len) == -1) { 182 fprintf(stderr, "munmap %s error=%d\n", 183 src_file, errno); 184 mret = 1; 185 } 186 } 187 188 exit2: 189 close(des_fid); 190 exit3: 191 close(src_fid); 192 193 return (mret); 194 } 195