1 /*- 2 * Copyright (c) 2014 Marcel Moolenaar 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/errno.h> 31 #include <assert.h> 32 #include <stdint.h> 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <unistd.h> 37 38 #include "endian.h" 39 #include "image.h" 40 #include "format.h" 41 #include "mkimg.h" 42 43 /* Default cluster sizes. */ 44 #define QCOW1_CLSTR_LOG2SZ 12 /* 4KB */ 45 #define QCOW2_CLSTR_LOG2SZ 16 /* 64KB */ 46 47 /* Flag bits in cluster offsets */ 48 #define QCOW_CLSTR_COMPRESSED (1ULL << 62) 49 #define QCOW_CLSTR_COPIED (1ULL << 63) 50 51 struct qcow_header { 52 uint32_t magic; 53 #define QCOW_MAGIC 0x514649fb 54 uint32_t version; 55 #define QCOW_VERSION_1 1 56 #define QCOW_VERSION_2 2 57 uint64_t path_offset; 58 uint32_t path_length; 59 uint32_t clstr_log2sz; /* v2 only */ 60 uint64_t disk_size; 61 union { 62 struct { 63 uint8_t clstr_log2sz; 64 uint8_t l2_log2sz; 65 uint16_t _pad; 66 uint32_t encryption; 67 uint64_t l1_offset; 68 } v1; 69 struct { 70 uint32_t encryption; 71 uint32_t l1_entries; 72 uint64_t l1_offset; 73 uint64_t refcnt_offset; 74 uint32_t refcnt_clstrs; 75 uint32_t snapshot_count; 76 uint64_t snapshot_offset; 77 } v2; 78 } u; 79 }; 80 81 static u_int clstr_log2sz; 82 83 static uint64_t 84 round_clstr(uint64_t ofs) 85 { 86 uint64_t clstrsz; 87 88 clstrsz = 1UL << clstr_log2sz; 89 return ((ofs + clstrsz - 1) & ~(clstrsz - 1)); 90 } 91 92 static int 93 qcow_resize(lba_t imgsz, u_int version) 94 { 95 uint64_t imagesz; 96 97 switch (version) { 98 case QCOW_VERSION_1: 99 clstr_log2sz = QCOW1_CLSTR_LOG2SZ; 100 break; 101 case QCOW_VERSION_2: 102 clstr_log2sz = QCOW2_CLSTR_LOG2SZ; 103 break; 104 default: 105 assert(0); 106 } 107 108 imagesz = round_clstr(imgsz * secsz); 109 110 if (verbose) 111 fprintf(stderr, "QCOW: image size = %ju, cluster size = %u\n", 112 (uintmax_t)imagesz, (u_int)(1U << clstr_log2sz)); 113 114 return (image_set_size(imagesz / secsz)); 115 } 116 117 static int 118 qcow1_resize(lba_t imgsz) 119 { 120 121 return (qcow_resize(imgsz, QCOW_VERSION_1)); 122 } 123 124 static int 125 qcow2_resize(lba_t imgsz) 126 { 127 128 return (qcow_resize(imgsz, QCOW_VERSION_2)); 129 } 130 131 static int 132 qcow_write(int fd, u_int version) 133 { 134 struct qcow_header *hdr; 135 uint64_t *l1tbl, *l2tbl, *rctbl; 136 uint16_t *rcblk; 137 uint64_t clstr_imgsz, clstr_l2tbls, clstr_l1tblsz; 138 uint64_t clstr_rcblks, clstr_rctblsz; 139 uint64_t n, imagesz, nclstrs, ofs, ofsflags; 140 lba_t blk, blkofs, blk_imgsz; 141 u_int l1clno, l2clno, rcclno; 142 u_int blk_clstrsz, refcnt_clstrs; 143 u_int clstrsz, l1idx, l2idx; 144 int error; 145 146 assert(clstr_log2sz != 0); 147 148 clstrsz = 1U << clstr_log2sz; 149 blk_clstrsz = clstrsz / secsz; 150 blk_imgsz = image_get_size(); 151 imagesz = blk_imgsz * secsz; 152 clstr_imgsz = imagesz >> clstr_log2sz; 153 clstr_l2tbls = round_clstr(clstr_imgsz * 8) >> clstr_log2sz; 154 clstr_l1tblsz = round_clstr(clstr_l2tbls * 8) >> clstr_log2sz; 155 nclstrs = clstr_imgsz + clstr_l2tbls + clstr_l1tblsz + 1; 156 clstr_rcblks = clstr_rctblsz = 0; 157 do { 158 n = clstr_rcblks + clstr_rctblsz; 159 clstr_rcblks = round_clstr((nclstrs + n) * 2) >> clstr_log2sz; 160 clstr_rctblsz = round_clstr(clstr_rcblks * 8) >> clstr_log2sz; 161 } while (n < (clstr_rcblks + clstr_rctblsz)); 162 163 /* 164 * We got all the sizes in clusters. Start the layout. 165 * 0 - header 166 * 1 - L1 table 167 * 2 - RC table (v2 only) 168 * 3 - L2 tables 169 * 4 - RC block (v2 only) 170 * 5 - data 171 */ 172 173 l1clno = 1; 174 rcclno = 0; 175 rctbl = l2tbl = l1tbl = NULL; 176 rcblk = NULL; 177 178 hdr = calloc(1, clstrsz); 179 if (hdr == NULL) 180 return (errno); 181 182 be32enc(&hdr->magic, QCOW_MAGIC); 183 be32enc(&hdr->version, version); 184 be64enc(&hdr->disk_size, imagesz); 185 switch (version) { 186 case QCOW_VERSION_1: 187 ofsflags = 0; 188 l2clno = l1clno + clstr_l1tblsz; 189 hdr->u.v1.clstr_log2sz = clstr_log2sz; 190 hdr->u.v1.l2_log2sz = clstr_log2sz - 3; 191 be64enc(&hdr->u.v1.l1_offset, clstrsz * l1clno); 192 break; 193 case QCOW_VERSION_2: 194 ofsflags = QCOW_CLSTR_COPIED; 195 rcclno = l1clno + clstr_l1tblsz; 196 l2clno = rcclno + clstr_rctblsz; 197 be32enc(&hdr->clstr_log2sz, clstr_log2sz); 198 be32enc(&hdr->u.v2.l1_entries, clstr_l2tbls); 199 be64enc(&hdr->u.v2.l1_offset, clstrsz * l1clno); 200 be64enc(&hdr->u.v2.refcnt_offset, clstrsz * rcclno); 201 refcnt_clstrs = round_clstr(clstr_rcblks * 8) >> clstr_log2sz; 202 be32enc(&hdr->u.v2.refcnt_clstrs, refcnt_clstrs); 203 break; 204 default: 205 assert(0); 206 } 207 208 if (sparse_write(fd, hdr, clstrsz) < 0) { 209 error = errno; 210 goto out; 211 } 212 213 free(hdr); 214 hdr = NULL; 215 216 ofs = clstrsz * l2clno; 217 nclstrs = 1 + clstr_l1tblsz + clstr_rctblsz; 218 219 l1tbl = calloc(clstr_l1tblsz, clstrsz); 220 if (l1tbl == NULL) { 221 error = ENOMEM; 222 goto out; 223 } 224 225 for (n = 0; n < clstr_imgsz; n++) { 226 blk = n * blk_clstrsz; 227 if (image_data(blk, blk_clstrsz)) { 228 nclstrs++; 229 l1idx = n >> (clstr_log2sz - 3); 230 if (l1tbl[l1idx] == 0) { 231 be64enc(l1tbl + l1idx, ofs + ofsflags); 232 ofs += clstrsz; 233 nclstrs++; 234 } 235 } 236 } 237 238 if (sparse_write(fd, l1tbl, clstrsz * clstr_l1tblsz) < 0) { 239 error = errno; 240 goto out; 241 } 242 243 clstr_rcblks = 0; 244 do { 245 n = clstr_rcblks; 246 clstr_rcblks = round_clstr((nclstrs + n) * 2) >> clstr_log2sz; 247 } while (n < clstr_rcblks); 248 249 if (rcclno > 0) { 250 rctbl = calloc(clstr_rctblsz, clstrsz); 251 if (rctbl == NULL) { 252 error = ENOMEM; 253 goto out; 254 } 255 for (n = 0; n < clstr_rcblks; n++) { 256 be64enc(rctbl + n, ofs); 257 ofs += clstrsz; 258 nclstrs++; 259 } 260 if (sparse_write(fd, rctbl, clstrsz * clstr_rctblsz) < 0) { 261 error = errno; 262 goto out; 263 } 264 free(rctbl); 265 rctbl = NULL; 266 } 267 268 l2tbl = malloc(clstrsz); 269 if (l2tbl == NULL) { 270 error = ENOMEM; 271 goto out; 272 } 273 274 for (l1idx = 0; l1idx < clstr_l2tbls; l1idx++) { 275 if (l1tbl[l1idx] == 0) 276 continue; 277 memset(l2tbl, 0, clstrsz); 278 blkofs = (lba_t)l1idx * blk_clstrsz * (clstrsz >> 3); 279 for (l2idx = 0; l2idx < (clstrsz >> 3); l2idx++) { 280 blk = blkofs + (lba_t)l2idx * blk_clstrsz; 281 if (blk >= blk_imgsz) 282 break; 283 if (image_data(blk, blk_clstrsz)) { 284 be64enc(l2tbl + l2idx, ofs + ofsflags); 285 ofs += clstrsz; 286 } 287 } 288 if (sparse_write(fd, l2tbl, clstrsz) < 0) { 289 error = errno; 290 goto out; 291 } 292 } 293 294 free(l2tbl); 295 l2tbl = NULL; 296 free(l1tbl); 297 l1tbl = NULL; 298 299 if (rcclno > 0) { 300 rcblk = calloc(clstr_rcblks, clstrsz); 301 if (rcblk == NULL) { 302 error = ENOMEM; 303 goto out; 304 } 305 for (n = 0; n < nclstrs; n++) 306 be16enc(rcblk + n, 1); 307 if (sparse_write(fd, rcblk, clstrsz * clstr_rcblks) < 0) { 308 error = errno; 309 goto out; 310 } 311 free(rcblk); 312 rcblk = NULL; 313 } 314 315 error = 0; 316 for (n = 0; n < clstr_imgsz; n++) { 317 blk = n * blk_clstrsz; 318 if (image_data(blk, blk_clstrsz)) { 319 error = image_copyout_region(fd, blk, blk_clstrsz); 320 if (error) 321 break; 322 } 323 } 324 if (!error) 325 error = image_copyout_done(fd); 326 327 out: 328 if (rcblk != NULL) 329 free(rcblk); 330 if (l2tbl != NULL) 331 free(l2tbl); 332 if (rctbl != NULL) 333 free(rctbl); 334 if (l1tbl != NULL) 335 free(l1tbl); 336 if (hdr != NULL) 337 free(hdr); 338 return (error); 339 } 340 341 static int 342 qcow1_write(int fd) 343 { 344 345 return (qcow_write(fd, QCOW_VERSION_1)); 346 } 347 348 static int 349 qcow2_write(int fd) 350 { 351 352 return (qcow_write(fd, QCOW_VERSION_2)); 353 } 354 355 static struct mkimg_format qcow1_format = { 356 .name = "qcow", 357 .description = "QEMU Copy-On-Write, version 1", 358 .resize = qcow1_resize, 359 .write = qcow1_write, 360 }; 361 FORMAT_DEFINE(qcow1_format); 362 363 static struct mkimg_format qcow2_format = { 364 .name = "qcow2", 365 .description = "QEMU Copy-On-Write, version 2", 366 .resize = qcow2_resize, 367 .write = qcow2_write, 368 }; 369 FORMAT_DEFINE(qcow2_format); 370