1 /* 2 * CDDL HEADER START 3 * 4 * This file and its contents are supplied under the terms of the 5 * Common Development and Distribution License ("CDDL"), version 1.0. 6 * You may only use this file in accordance with the terms of version 7 * 1.0 of the CDDL. 8 * 9 * A full copy of the text of the CDDL should have accompanied this 10 * source. A copy of the CDDL is also available via the Internet at 11 * http://www.illumos.org/license/CDDL. 12 * 13 * CDDL HEADER END 14 */ 15 16 /* 17 * Copyright (c) 2020 by Delphix. All rights reserved. 18 */ 19 20 #include <assert.h> 21 #include <cityhash.h> 22 #include <ctype.h> 23 #include <errno.h> 24 #include <fcntl.h> 25 #include <libzfs.h> 26 #include <libzutil.h> 27 #include <stddef.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <umem.h> 32 #include <unistd.h> 33 #include <sys/debug.h> 34 #include <sys/stat.h> 35 #include <sys/zfs_ioctl.h> 36 #include <sys/zio_checksum.h> 37 #include "zfs_fletcher.h" 38 #include "zstream.h" 39 40 41 #define MAX_RDT_PHYSMEM_PERCENT 20 42 #define SMALLEST_POSSIBLE_MAX_RDT_MB 128 43 44 typedef struct redup_entry { 45 struct redup_entry *rde_next; 46 uint64_t rde_guid; 47 uint64_t rde_object; 48 uint64_t rde_offset; 49 uint64_t rde_stream_offset; 50 } redup_entry_t; 51 52 typedef struct redup_table { 53 redup_entry_t **redup_hash_array; 54 umem_cache_t *ddecache; 55 uint64_t ddt_count; 56 int numhashbits; 57 } redup_table_t; 58 59 int 60 highbit64(uint64_t i) 61 { 62 if (i == 0) 63 return (0); 64 65 return (NBBY * sizeof (uint64_t) - __builtin_clzll(i)); 66 } 67 68 static void * 69 safe_calloc(size_t n) 70 { 71 void *rv = calloc(1, n); 72 if (rv == NULL) { 73 fprintf(stderr, 74 "Error: could not allocate %u bytes of memory\n", 75 (int)n); 76 exit(1); 77 } 78 return (rv); 79 } 80 81 /* 82 * Safe version of fread(), exits on error. 83 */ 84 static int 85 sfread(void *buf, size_t size, FILE *fp) 86 { 87 int rv = fread(buf, size, 1, fp); 88 if (rv == 0 && ferror(fp)) { 89 (void) fprintf(stderr, "Error while reading file: %s\n", 90 strerror(errno)); 91 exit(1); 92 } 93 return (rv); 94 } 95 96 /* 97 * Safe version of pread(), exits on error. 98 */ 99 static void 100 spread(int fd, void *buf, size_t count, off_t offset) 101 { 102 ssize_t err = pread(fd, buf, count, offset); 103 if (err == -1) { 104 (void) fprintf(stderr, 105 "Error while reading file: %s\n", 106 strerror(errno)); 107 exit(1); 108 } else if (err != count) { 109 (void) fprintf(stderr, 110 "Error while reading file: short read\n"); 111 exit(1); 112 } 113 } 114 115 static int 116 dump_record(dmu_replay_record_t *drr, void *payload, int payload_len, 117 zio_cksum_t *zc, int outfd) 118 { 119 assert(offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum) 120 == sizeof (dmu_replay_record_t) - sizeof (zio_cksum_t)); 121 fletcher_4_incremental_native(drr, 122 offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum), zc); 123 if (drr->drr_type != DRR_BEGIN) { 124 assert(ZIO_CHECKSUM_IS_ZERO(&drr->drr_u. 125 drr_checksum.drr_checksum)); 126 drr->drr_u.drr_checksum.drr_checksum = *zc; 127 } 128 fletcher_4_incremental_native(&drr->drr_u.drr_checksum.drr_checksum, 129 sizeof (zio_cksum_t), zc); 130 if (write(outfd, drr, sizeof (*drr)) == -1) 131 return (errno); 132 if (payload_len != 0) { 133 fletcher_4_incremental_native(payload, payload_len, zc); 134 if (write(outfd, payload, payload_len) == -1) 135 return (errno); 136 } 137 return (0); 138 } 139 140 static void 141 rdt_insert(redup_table_t *rdt, 142 uint64_t guid, uint64_t object, uint64_t offset, uint64_t stream_offset) 143 { 144 uint64_t ch = cityhash4(guid, object, offset, 0); 145 uint64_t hashcode = BF64_GET(ch, 0, rdt->numhashbits); 146 redup_entry_t **rdepp; 147 148 rdepp = &(rdt->redup_hash_array[hashcode]); 149 redup_entry_t *rde = umem_cache_alloc(rdt->ddecache, UMEM_NOFAIL); 150 rde->rde_next = *rdepp; 151 rde->rde_guid = guid; 152 rde->rde_object = object; 153 rde->rde_offset = offset; 154 rde->rde_stream_offset = stream_offset; 155 *rdepp = rde; 156 rdt->ddt_count++; 157 } 158 159 static void 160 rdt_lookup(redup_table_t *rdt, 161 uint64_t guid, uint64_t object, uint64_t offset, 162 uint64_t *stream_offsetp) 163 { 164 uint64_t ch = cityhash4(guid, object, offset, 0); 165 uint64_t hashcode = BF64_GET(ch, 0, rdt->numhashbits); 166 167 for (redup_entry_t *rde = rdt->redup_hash_array[hashcode]; 168 rde != NULL; rde = rde->rde_next) { 169 if (rde->rde_guid == guid && 170 rde->rde_object == object && 171 rde->rde_offset == offset) { 172 *stream_offsetp = rde->rde_stream_offset; 173 return; 174 } 175 } 176 assert(!"could not find expected redup table entry"); 177 } 178 179 /* 180 * Convert a dedup stream (generated by "zfs send -D") to a 181 * non-deduplicated stream. The entire infd will be converted, including 182 * any substreams in a stream package (generated by "zfs send -RD"). The 183 * infd must be seekable. 184 */ 185 static void 186 zfs_redup_stream(int infd, int outfd, boolean_t verbose) 187 { 188 int bufsz = SPA_MAXBLOCKSIZE; 189 dmu_replay_record_t thedrr = { 0 }; 190 dmu_replay_record_t *drr = &thedrr; 191 redup_table_t rdt; 192 zio_cksum_t stream_cksum; 193 uint64_t numbuckets; 194 uint64_t num_records = 0; 195 uint64_t num_write_byref_records = 0; 196 197 #ifdef _ILP32 198 uint64_t max_rde_size = SMALLEST_POSSIBLE_MAX_RDT_MB << 20; 199 #else 200 uint64_t physmem = sysconf(_SC_PHYS_PAGES) * sysconf(_SC_PAGESIZE); 201 uint64_t max_rde_size = 202 MAX((physmem * MAX_RDT_PHYSMEM_PERCENT) / 100, 203 SMALLEST_POSSIBLE_MAX_RDT_MB << 20); 204 #endif 205 206 numbuckets = max_rde_size / (sizeof (redup_entry_t)); 207 208 /* 209 * numbuckets must be a power of 2. Increase number to 210 * a power of 2 if necessary. 211 */ 212 if (!ISP2(numbuckets)) 213 numbuckets = 1ULL << highbit64(numbuckets); 214 215 rdt.redup_hash_array = 216 safe_calloc(numbuckets * sizeof (redup_entry_t *)); 217 rdt.ddecache = umem_cache_create("rde", sizeof (redup_entry_t), 0, 218 NULL, NULL, NULL, NULL, NULL, 0); 219 rdt.numhashbits = highbit64(numbuckets) - 1; 220 rdt.ddt_count = 0; 221 222 char *buf = safe_calloc(bufsz); 223 FILE *ofp = fdopen(infd, "r"); 224 long offset = ftell(ofp); 225 while (sfread(drr, sizeof (*drr), ofp) != 0) { 226 num_records++; 227 228 /* 229 * We need to regenerate the checksum. 230 */ 231 if (drr->drr_type != DRR_BEGIN) { 232 memset(&drr->drr_u.drr_checksum.drr_checksum, 0, 233 sizeof (drr->drr_u.drr_checksum.drr_checksum)); 234 } 235 236 uint64_t payload_size = 0; 237 switch (drr->drr_type) { 238 case DRR_BEGIN: 239 { 240 struct drr_begin *drrb = &drr->drr_u.drr_begin; 241 int fflags; 242 ZIO_SET_CHECKSUM(&stream_cksum, 0, 0, 0, 0); 243 244 assert(drrb->drr_magic == DMU_BACKUP_MAGIC); 245 246 /* clear the DEDUP feature flag for this stream */ 247 fflags = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo); 248 fflags &= ~(DMU_BACKUP_FEATURE_DEDUP | 249 DMU_BACKUP_FEATURE_DEDUPPROPS); 250 /* cppcheck-suppress syntaxError */ 251 DMU_SET_FEATUREFLAGS(drrb->drr_versioninfo, fflags); 252 253 int sz = drr->drr_payloadlen; 254 if (sz != 0) { 255 if (sz > bufsz) { 256 free(buf); 257 buf = safe_calloc(sz); 258 bufsz = sz; 259 } 260 (void) sfread(buf, sz, ofp); 261 } 262 payload_size = sz; 263 break; 264 } 265 266 case DRR_END: 267 { 268 struct drr_end *drre = &drr->drr_u.drr_end; 269 /* 270 * Use the recalculated checksum, unless this is 271 * the END record of a stream package, which has 272 * no checksum. 273 */ 274 if (!ZIO_CHECKSUM_IS_ZERO(&drre->drr_checksum)) 275 drre->drr_checksum = stream_cksum; 276 break; 277 } 278 279 case DRR_OBJECT: 280 { 281 struct drr_object *drro = &drr->drr_u.drr_object; 282 283 if (drro->drr_bonuslen > 0) { 284 payload_size = DRR_OBJECT_PAYLOAD_SIZE(drro); 285 (void) sfread(buf, payload_size, ofp); 286 } 287 break; 288 } 289 290 case DRR_SPILL: 291 { 292 struct drr_spill *drrs = &drr->drr_u.drr_spill; 293 payload_size = DRR_SPILL_PAYLOAD_SIZE(drrs); 294 (void) sfread(buf, payload_size, ofp); 295 break; 296 } 297 298 case DRR_WRITE_BYREF: 299 { 300 struct drr_write_byref drrwb = 301 drr->drr_u.drr_write_byref; 302 303 num_write_byref_records++; 304 305 /* 306 * Look up in hash table by drrwb->drr_refguid, 307 * drr_refobject, drr_refoffset. Replace this 308 * record with the found WRITE record, but with 309 * drr_object,drr_offset,drr_toguid replaced with ours. 310 */ 311 uint64_t stream_offset = 0; 312 rdt_lookup(&rdt, drrwb.drr_refguid, 313 drrwb.drr_refobject, drrwb.drr_refoffset, 314 &stream_offset); 315 316 spread(infd, drr, sizeof (*drr), stream_offset); 317 318 assert(drr->drr_type == DRR_WRITE); 319 struct drr_write *drrw = &drr->drr_u.drr_write; 320 assert(drrw->drr_toguid == drrwb.drr_refguid); 321 assert(drrw->drr_object == drrwb.drr_refobject); 322 assert(drrw->drr_offset == drrwb.drr_refoffset); 323 324 payload_size = DRR_WRITE_PAYLOAD_SIZE(drrw); 325 spread(infd, buf, payload_size, 326 stream_offset + sizeof (*drr)); 327 328 drrw->drr_toguid = drrwb.drr_toguid; 329 drrw->drr_object = drrwb.drr_object; 330 drrw->drr_offset = drrwb.drr_offset; 331 break; 332 } 333 334 case DRR_WRITE: 335 { 336 struct drr_write *drrw = &drr->drr_u.drr_write; 337 payload_size = DRR_WRITE_PAYLOAD_SIZE(drrw); 338 (void) sfread(buf, payload_size, ofp); 339 340 rdt_insert(&rdt, drrw->drr_toguid, 341 drrw->drr_object, drrw->drr_offset, offset); 342 break; 343 } 344 345 case DRR_WRITE_EMBEDDED: 346 { 347 struct drr_write_embedded *drrwe = 348 &drr->drr_u.drr_write_embedded; 349 payload_size = 350 P2ROUNDUP((uint64_t)drrwe->drr_psize, 8); 351 (void) sfread(buf, payload_size, ofp); 352 break; 353 } 354 355 case DRR_FREEOBJECTS: 356 case DRR_FREE: 357 case DRR_OBJECT_RANGE: 358 break; 359 360 default: 361 (void) fprintf(stderr, "INVALID record type 0x%x\n", 362 drr->drr_type); 363 /* should never happen, so assert */ 364 assert(B_FALSE); 365 } 366 367 if (feof(ofp)) { 368 fprintf(stderr, "Error: unexpected end-of-file\n"); 369 exit(1); 370 } 371 if (ferror(ofp)) { 372 fprintf(stderr, "Error while reading file: %s\n", 373 strerror(errno)); 374 exit(1); 375 } 376 377 /* 378 * We need to recalculate the checksum, and it needs to be 379 * initially zero to do that. BEGIN records don't have 380 * a checksum. 381 */ 382 if (drr->drr_type != DRR_BEGIN) { 383 memset(&drr->drr_u.drr_checksum.drr_checksum, 0, 384 sizeof (drr->drr_u.drr_checksum.drr_checksum)); 385 } 386 if (dump_record(drr, buf, payload_size, 387 &stream_cksum, outfd) != 0) 388 break; 389 if (drr->drr_type == DRR_END) { 390 /* 391 * Typically the END record is either the last 392 * thing in the stream, or it is followed 393 * by a BEGIN record (which also zeros the checksum). 394 * However, a stream package ends with two END 395 * records. The last END record's checksum starts 396 * from zero. 397 */ 398 ZIO_SET_CHECKSUM(&stream_cksum, 0, 0, 0, 0); 399 } 400 offset = ftell(ofp); 401 } 402 403 if (verbose) { 404 char mem_str[16]; 405 zfs_nicenum(rdt.ddt_count * sizeof (redup_entry_t), 406 mem_str, sizeof (mem_str)); 407 fprintf(stderr, "converted stream with %llu total records, " 408 "including %llu dedup records, using %sB memory.\n", 409 (long long)num_records, 410 (long long)num_write_byref_records, 411 mem_str); 412 } 413 414 umem_cache_destroy(rdt.ddecache); 415 free(rdt.redup_hash_array); 416 free(buf); 417 (void) fclose(ofp); 418 } 419 420 int 421 zstream_do_redup(int argc, char *argv[]) 422 { 423 boolean_t verbose = B_FALSE; 424 int c; 425 426 while ((c = getopt(argc, argv, "v")) != -1) { 427 switch (c) { 428 case 'v': 429 verbose = B_TRUE; 430 break; 431 case '?': 432 (void) fprintf(stderr, "invalid option '%c'\n", 433 optopt); 434 zstream_usage(); 435 break; 436 } 437 } 438 439 argc -= optind; 440 argv += optind; 441 442 if (argc != 1) 443 zstream_usage(); 444 445 const char *filename = argv[0]; 446 447 if (isatty(STDOUT_FILENO)) { 448 (void) fprintf(stderr, 449 "Error: Stream can not be written to a terminal.\n" 450 "You must redirect standard output.\n"); 451 return (1); 452 } 453 454 int fd = open(filename, O_RDONLY); 455 if (fd == -1) { 456 (void) fprintf(stderr, 457 "Error while opening file '%s': %s\n", 458 filename, strerror(errno)); 459 exit(1); 460 } 461 462 fletcher_4_init(); 463 zfs_redup_stream(fd, STDOUT_FILENO, verbose); 464 fletcher_4_fini(); 465 466 close(fd); 467 468 return (0); 469 } 470