1 /* 2 * Copyright (c) 2011-2015 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@dragonflybsd.org> 6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org> 7 * by Daniel Flores (GSOC 2013 - mentored by Matthew Dillon, compression) 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 3. Neither the name of The DragonFly Project nor the names of its 20 * contributors may be used to endorse or promote products derived 21 * from this software without specific, prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 /* 37 * This module handles low level logical file I/O (strategy) which backs 38 * the logical buffer cache. 39 * 40 * [De]compression, zero-block, check codes, and buffer cache operations 41 * for file data is handled here. 42 * 43 * Live dedup makes its home here as well. 44 */ 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/fcntl.h> 50 #include <sys/buf.h> 51 #include <sys/proc.h> 52 #include <sys/namei.h> 53 #include <sys/mount.h> 54 #include <sys/vnode.h> 55 #include <sys/mountctl.h> 56 #include <sys/dirent.h> 57 #include <sys/uio.h> 58 #include <sys/objcache.h> 59 #include <sys/event.h> 60 #include <sys/file.h> 61 #include <vfs/fifofs/fifo.h> 62 63 #include "hammer2.h" 64 #include "hammer2_lz4.h" 65 66 #include "zlib/hammer2_zlib.h" 67 68 struct objcache *cache_buffer_read; 69 struct objcache *cache_buffer_write; 70 71 /* 72 * Strategy code (async logical file buffer I/O from system) 73 * 74 * Except for the transaction init (which should normally not block), 75 * we essentially run the strategy operation asynchronously via a XOP. 76 * 77 * XXX This isn't supposed to be able to deadlock against vfs_sync vfsync() 78 * calls but it has in the past when multiple flushes are queued. 79 * 80 * XXX We currently terminate the transaction once we get a quorum, otherwise 81 * the frontend can stall, but this can leave the remaining nodes with 82 * a potential flush conflict. We need to delay flushes on those nodes 83 * until running transactions complete separately from the normal 84 * transaction sequencing. FIXME TODO. 85 */ 86 static void hammer2_strategy_xop_read(hammer2_thread_t *thr, 87 hammer2_xop_t *arg); 88 static void hammer2_strategy_xop_write(hammer2_thread_t *thr, 89 hammer2_xop_t *arg); 90 static int hammer2_strategy_read(struct vop_strategy_args *ap); 91 static int hammer2_strategy_write(struct vop_strategy_args *ap); 92 static void hammer2_strategy_read_completion(hammer2_chain_t *chain, 93 char *data, struct bio *bio); 94 95 static hammer2_off_t hammer2_dedup_lookup(hammer2_dev_t *hmp, 96 char **datap, int pblksize); 97 98 int h2timer[32]; 99 int h2last; 100 int h2lid; 101 102 #define TIMER(which) do { \ 103 if (h2last) \ 104 h2timer[h2lid] += (int)(ticks - h2last);\ 105 h2last = ticks; \ 106 h2lid = which; \ 107 } while(0) 108 109 int 110 hammer2_vop_strategy(struct vop_strategy_args *ap) 111 { 112 struct bio *biop; 113 struct buf *bp; 114 int error; 115 116 biop = ap->a_bio; 117 bp = biop->bio_buf; 118 119 switch(bp->b_cmd) { 120 case BUF_CMD_READ: 121 error = hammer2_strategy_read(ap); 122 ++hammer2_iod_file_read; 123 break; 124 case BUF_CMD_WRITE: 125 error = hammer2_strategy_write(ap); 126 ++hammer2_iod_file_write; 127 break; 128 default: 129 bp->b_error = error = EINVAL; 130 bp->b_flags |= B_ERROR; 131 biodone(biop); 132 break; 133 } 134 return (error); 135 } 136 137 /* 138 * Return the largest contiguous physical disk range for the logical 139 * request, in bytes. 140 * 141 * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb) 142 * 143 * Basically disabled, the logical buffer write thread has to deal with 144 * buffers one-at-a-time. Note that this should not prevent cluster_read() 145 * from reading-ahead, it simply prevents it from trying form a single 146 * cluster buffer for the logical request. H2 already uses 64KB buffers! 147 */ 148 int 149 hammer2_vop_bmap(struct vop_bmap_args *ap) 150 { 151 *ap->a_doffsetp = NOOFFSET; 152 if (ap->a_runp) 153 *ap->a_runp = 0; 154 if (ap->a_runb) 155 *ap->a_runb = 0; 156 return (EOPNOTSUPP); 157 } 158 159 /**************************************************************************** 160 * READ SUPPORT * 161 ****************************************************************************/ 162 /* 163 * Callback used in read path in case that a block is compressed with LZ4. 164 */ 165 static 166 void 167 hammer2_decompress_LZ4_callback(const char *data, u_int bytes, struct bio *bio) 168 { 169 struct buf *bp; 170 char *compressed_buffer; 171 int compressed_size; 172 int result; 173 174 bp = bio->bio_buf; 175 176 #if 0 177 if bio->bio_caller_info2.index && 178 bio->bio_caller_info1.uvalue32 != 179 crc32(bp->b_data, bp->b_bufsize) --- return error 180 #endif 181 182 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 183 compressed_size = *(const int *)data; 184 KKASSERT((uint32_t)compressed_size <= bytes - sizeof(int)); 185 186 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 187 result = LZ4_decompress_safe(__DECONST(char *, &data[sizeof(int)]), 188 compressed_buffer, 189 compressed_size, 190 bp->b_bufsize); 191 if (result < 0) { 192 kprintf("READ PATH: Error during decompression." 193 "bio %016jx/%d\n", 194 (intmax_t)bio->bio_offset, bytes); 195 /* make sure it isn't random garbage */ 196 bzero(compressed_buffer, bp->b_bufsize); 197 } 198 KKASSERT(result <= bp->b_bufsize); 199 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 200 if (result < bp->b_bufsize) 201 bzero(bp->b_data + result, bp->b_bufsize - result); 202 objcache_put(cache_buffer_read, compressed_buffer); 203 bp->b_resid = 0; 204 bp->b_flags |= B_AGE; 205 } 206 207 /* 208 * Callback used in read path in case that a block is compressed with ZLIB. 209 * It is almost identical to LZ4 callback, so in theory they can be unified, 210 * but we didn't want to make changes in bio structure for that. 211 */ 212 static 213 void 214 hammer2_decompress_ZLIB_callback(const char *data, u_int bytes, struct bio *bio) 215 { 216 struct buf *bp; 217 char *compressed_buffer; 218 z_stream strm_decompress; 219 int result; 220 int ret; 221 222 bp = bio->bio_buf; 223 224 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 225 strm_decompress.avail_in = 0; 226 strm_decompress.next_in = Z_NULL; 227 228 ret = inflateInit(&strm_decompress); 229 230 if (ret != Z_OK) 231 kprintf("HAMMER2 ZLIB: Fatal error in inflateInit.\n"); 232 233 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 234 strm_decompress.next_in = __DECONST(char *, data); 235 236 /* XXX supply proper size, subset of device bp */ 237 strm_decompress.avail_in = bytes; 238 strm_decompress.next_out = compressed_buffer; 239 strm_decompress.avail_out = bp->b_bufsize; 240 241 ret = inflate(&strm_decompress, Z_FINISH); 242 if (ret != Z_STREAM_END) { 243 kprintf("HAMMER2 ZLIB: Fatar error during decompression.\n"); 244 bzero(compressed_buffer, bp->b_bufsize); 245 } 246 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 247 result = bp->b_bufsize - strm_decompress.avail_out; 248 if (result < bp->b_bufsize) 249 bzero(bp->b_data + result, strm_decompress.avail_out); 250 objcache_put(cache_buffer_read, compressed_buffer); 251 ret = inflateEnd(&strm_decompress); 252 253 bp->b_resid = 0; 254 bp->b_flags |= B_AGE; 255 } 256 257 /* 258 * Logical buffer I/O, async read. 259 */ 260 static 261 int 262 hammer2_strategy_read(struct vop_strategy_args *ap) 263 { 264 hammer2_xop_strategy_t *xop; 265 struct buf *bp; 266 struct bio *bio; 267 struct bio *nbio; 268 hammer2_inode_t *ip; 269 hammer2_key_t lbase; 270 271 bio = ap->a_bio; 272 bp = bio->bio_buf; 273 ip = VTOI(ap->a_vp); 274 nbio = push_bio(bio); 275 276 lbase = bio->bio_offset; 277 KKASSERT(((int)lbase & HAMMER2_PBUFMASK) == 0); 278 279 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_STRATEGY); 280 xop->finished = 0; 281 xop->bio = bio; 282 xop->lbase = lbase; 283 hammer2_mtx_init(&xop->lock, "h2bior"); 284 hammer2_xop_start(&xop->head, hammer2_strategy_xop_read); 285 /* asynchronous completion */ 286 287 return(0); 288 } 289 290 /* 291 * Per-node XOP (threaded), do a synchronous lookup of the chain and 292 * its data. The frontend is asynchronous, so we are also responsible 293 * for racing to terminate the frontend. 294 */ 295 static 296 void 297 hammer2_strategy_xop_read(hammer2_thread_t *thr, hammer2_xop_t *arg) 298 { 299 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 300 hammer2_chain_t *parent; 301 hammer2_chain_t *chain; 302 hammer2_key_t key_dummy; 303 hammer2_key_t lbase; 304 struct bio *bio; 305 struct buf *bp; 306 int cache_index = -1; 307 int error; 308 309 /* 310 * Note that we can race completion of the bio supplied by 311 * the front-end so we cannot access it until we determine 312 * that we are the ones finishing it up. 313 */ 314 TIMER(0); 315 lbase = xop->lbase; 316 317 /* 318 * This is difficult to optimize. The logical buffer might be 319 * partially dirty (contain dummy zero-fill pages), which would 320 * mess up our crc calculation if we were to try a direct read. 321 * So for now we always double-buffer through the underlying 322 * storage. 323 * 324 * If not for the above problem we could conditionalize on 325 * (1) 64KB buffer, (2) one chain (not multi-master) and 326 * (3) !hammer2_double_buffer, and issue a direct read into the 327 * logical buffer. 328 */ 329 parent = hammer2_inode_chain(xop->head.ip1, thr->clindex, 330 HAMMER2_RESOLVE_ALWAYS | 331 HAMMER2_RESOLVE_SHARED); 332 TIMER(1); 333 if (parent) { 334 chain = hammer2_chain_lookup(&parent, &key_dummy, 335 lbase, lbase, 336 &cache_index, 337 HAMMER2_LOOKUP_ALWAYS | 338 HAMMER2_LOOKUP_SHARED); 339 error = chain ? chain->error : 0; 340 } else { 341 error = EIO; 342 chain = NULL; 343 } 344 TIMER(2); 345 error = hammer2_xop_feed(&xop->head, chain, thr->clindex, error); 346 TIMER(3); 347 if (chain) { 348 hammer2_chain_unlock(chain); 349 hammer2_chain_drop(chain); 350 } 351 if (parent) { 352 hammer2_chain_unlock(parent); 353 hammer2_chain_drop(parent); 354 } 355 chain = NULL; /* safety */ 356 parent = NULL; /* safety */ 357 TIMER(4); 358 359 /* 360 * Race to finish the frontend. First-to-complete. bio is only 361 * valid if we are determined to be the ones able to complete 362 * the operation. 363 */ 364 if (xop->finished) 365 return; 366 hammer2_mtx_ex(&xop->lock); 367 if (xop->finished) { 368 hammer2_mtx_unlock(&xop->lock); 369 return; 370 } 371 bio = xop->bio; 372 bp = bio->bio_buf; 373 374 /* 375 * Async operation has not completed and we now own the lock. 376 * Determine if we can complete the operation by issuing the 377 * frontend collection non-blocking. 378 * 379 * H2 double-buffers the data, setting B_NOTMETA on the logical 380 * buffer hints to the OS that the logical buffer should not be 381 * swapcached (since the device buffer can be). 382 * 383 * Also note that even for compressed data we would rather the 384 * kernel cache/swapcache device buffers more and (decompressed) 385 * logical buffers less, since that will significantly improve 386 * the amount of end-user data that can be cached. 387 */ 388 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 389 TIMER(5); 390 391 switch(error) { 392 case 0: 393 xop->finished = 1; 394 hammer2_mtx_unlock(&xop->lock); 395 bp->b_flags |= B_NOTMETA; 396 chain = xop->head.cluster.focus; 397 hammer2_strategy_read_completion(chain, (char *)chain->data, 398 xop->bio); 399 biodone(bio); 400 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 401 break; 402 case ENOENT: 403 xop->finished = 1; 404 hammer2_mtx_unlock(&xop->lock); 405 bp->b_flags |= B_NOTMETA; 406 bp->b_resid = 0; 407 bp->b_error = 0; 408 bzero(bp->b_data, bp->b_bcount); 409 biodone(bio); 410 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 411 break; 412 case EINPROGRESS: 413 hammer2_mtx_unlock(&xop->lock); 414 break; 415 default: 416 kprintf("strategy_xop_read: error %d loff=%016jx\n", 417 error, bp->b_loffset); 418 xop->finished = 1; 419 hammer2_mtx_unlock(&xop->lock); 420 bp->b_flags |= B_ERROR; 421 bp->b_error = EIO; 422 biodone(bio); 423 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 424 break; 425 } 426 TIMER(6); 427 } 428 429 static 430 void 431 hammer2_strategy_read_completion(hammer2_chain_t *chain, char *data, 432 struct bio *bio) 433 { 434 struct buf *bp = bio->bio_buf; 435 436 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 437 /* 438 * Copy from in-memory inode structure. 439 */ 440 bcopy(((hammer2_inode_data_t *)data)->u.data, 441 bp->b_data, HAMMER2_EMBEDDED_BYTES); 442 bzero(bp->b_data + HAMMER2_EMBEDDED_BYTES, 443 bp->b_bcount - HAMMER2_EMBEDDED_BYTES); 444 bp->b_resid = 0; 445 bp->b_error = 0; 446 } else if (chain->bref.type == HAMMER2_BREF_TYPE_DATA) { 447 /* 448 * Data is on-media, record for live dedup. Release the 449 * chain (try to free it) when done. The data is still 450 * cached by both the buffer cache in front and the 451 * block device behind us. This leaves more room in the 452 * LRU chain cache for meta-data chains which we really 453 * want to retain. 454 */ 455 hammer2_dedup_record(chain, data); 456 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE); 457 458 /* 459 * Decompression and copy. 460 */ 461 switch (HAMMER2_DEC_COMP(chain->bref.methods)) { 462 case HAMMER2_COMP_LZ4: 463 hammer2_decompress_LZ4_callback(data, chain->bytes, 464 bio); 465 /* b_resid set by call */ 466 break; 467 case HAMMER2_COMP_ZLIB: 468 hammer2_decompress_ZLIB_callback(data, chain->bytes, 469 bio); 470 /* b_resid set by call */ 471 break; 472 case HAMMER2_COMP_NONE: 473 KKASSERT(chain->bytes <= bp->b_bcount); 474 bcopy(data, bp->b_data, chain->bytes); 475 if (chain->bytes < bp->b_bcount) { 476 bzero(bp->b_data + chain->bytes, 477 bp->b_bcount - chain->bytes); 478 } 479 bp->b_resid = 0; 480 bp->b_error = 0; 481 break; 482 default: 483 panic("hammer2_strategy_read: " 484 "unknown compression type"); 485 } 486 } else { 487 panic("hammer2_strategy_read: unknown bref type"); 488 } 489 } 490 491 /**************************************************************************** 492 * WRITE SUPPORT * 493 ****************************************************************************/ 494 495 /* 496 * Functions for compression in threads, 497 * from hammer2_vnops.c 498 */ 499 static void hammer2_write_file_core(char *data, hammer2_inode_t *ip, 500 hammer2_chain_t **parentp, 501 hammer2_key_t lbase, int ioflag, int pblksize, 502 hammer2_tid_t mtid, int *errorp); 503 static void hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 504 hammer2_chain_t **parentp, 505 hammer2_key_t lbase, int ioflag, int pblksize, 506 hammer2_tid_t mtid, int *errorp, 507 int comp_algo, int check_algo); 508 static void hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 509 hammer2_chain_t **parentp, 510 hammer2_key_t lbase, int ioflag, int pblksize, 511 hammer2_tid_t mtid, int *errorp, 512 int check_algo); 513 static int test_block_zeros(const char *buf, size_t bytes); 514 static void zero_write(char *data, hammer2_inode_t *ip, 515 hammer2_chain_t **parentp, 516 hammer2_key_t lbase, 517 hammer2_tid_t mtid, int *errorp); 518 static void hammer2_write_bp(hammer2_chain_t *chain, char *data, 519 int ioflag, int pblksize, 520 hammer2_tid_t mtid, int *errorp, 521 int check_algo); 522 523 static 524 int 525 hammer2_strategy_write(struct vop_strategy_args *ap) 526 { 527 hammer2_xop_strategy_t *xop; 528 hammer2_pfs_t *pmp; 529 struct bio *bio; 530 struct buf *bp; 531 hammer2_inode_t *ip; 532 533 bio = ap->a_bio; 534 bp = bio->bio_buf; 535 ip = VTOI(ap->a_vp); 536 pmp = ip->pmp; 537 538 hammer2_lwinprog_ref(pmp); 539 hammer2_trans_assert_strategy(pmp); 540 hammer2_trans_init(pmp, HAMMER2_TRANS_BUFCACHE); 541 542 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING | 543 HAMMER2_XOP_STRATEGY); 544 xop->finished = 0; 545 xop->bio = bio; 546 xop->lbase = bio->bio_offset; 547 hammer2_mtx_init(&xop->lock, "h2biow"); 548 hammer2_xop_start(&xop->head, hammer2_strategy_xop_write); 549 /* asynchronous completion */ 550 551 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 552 553 return(0); 554 } 555 556 /* 557 * Per-node XOP (threaded). Write the logical buffer to the media. 558 * 559 * This is a bit problematic because there may be multiple target and 560 * any of them may be able to release the bp. In addition, if our 561 * particulr target is offline we don't want to block the bp (and thus 562 * the frontend). To accomplish this we copy the data to the per-thr 563 * scratch buffer. 564 */ 565 static 566 void 567 hammer2_strategy_xop_write(hammer2_thread_t *thr, hammer2_xop_t *arg) 568 { 569 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 570 hammer2_chain_t *parent; 571 hammer2_key_t lbase; 572 hammer2_inode_t *ip; 573 struct bio *bio; 574 struct buf *bp; 575 int error; 576 int lblksize; 577 int pblksize; 578 hammer2_off_t bio_offset; 579 char *bio_data; 580 581 /* 582 * We can only access the bp/bio if the frontend has not yet 583 * completed. 584 */ 585 if (xop->finished) 586 return; 587 hammer2_mtx_sh(&xop->lock); 588 if (xop->finished) { 589 hammer2_mtx_unlock(&xop->lock); 590 return; 591 } 592 593 lbase = xop->lbase; 594 bio = xop->bio; /* ephermal */ 595 bp = bio->bio_buf; /* ephermal */ 596 ip = xop->head.ip1; /* retained by ref */ 597 bio_offset = bio->bio_offset; 598 bio_data = thr->scratch; 599 600 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 601 602 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 603 pblksize = hammer2_calc_physical(ip, lbase); 604 bcopy(bp->b_data, bio_data, lblksize); 605 606 hammer2_mtx_unlock(&xop->lock); 607 bp = NULL; /* safety, illegal to access after unlock */ 608 bio = NULL; /* safety, illegal to access after unlock */ 609 610 /* 611 * Actual operation 612 */ 613 parent = hammer2_inode_chain(ip, thr->clindex, HAMMER2_RESOLVE_ALWAYS); 614 hammer2_write_file_core(bio_data, ip, &parent, 615 lbase, IO_ASYNC, pblksize, 616 xop->head.mtid, &error); 617 if (parent) { 618 hammer2_chain_unlock(parent); 619 hammer2_chain_drop(parent); 620 parent = NULL; /* safety */ 621 } 622 hammer2_xop_feed(&xop->head, NULL, thr->clindex, error); 623 624 /* 625 * Try to complete the operation on behalf of the front-end. 626 */ 627 if (xop->finished) 628 return; 629 hammer2_mtx_ex(&xop->lock); 630 if (xop->finished) { 631 hammer2_mtx_unlock(&xop->lock); 632 return; 633 } 634 635 /* 636 * Async operation has not completed and we now own the lock. 637 * Determine if we can complete the operation by issuing the 638 * frontend collection non-blocking. 639 * 640 * H2 double-buffers the data, setting B_NOTMETA on the logical 641 * buffer hints to the OS that the logical buffer should not be 642 * swapcached (since the device buffer can be). 643 */ 644 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 645 646 if (error == EINPROGRESS) { 647 hammer2_mtx_unlock(&xop->lock); 648 return; 649 } 650 651 /* 652 * Async operation has completed. 653 */ 654 xop->finished = 1; 655 hammer2_mtx_unlock(&xop->lock); 656 657 bio = xop->bio; /* now owned by us */ 658 bp = bio->bio_buf; /* now owned by us */ 659 660 if (error == ENOENT || error == 0) { 661 bp->b_flags |= B_NOTMETA; 662 bp->b_resid = 0; 663 bp->b_error = 0; 664 biodone(bio); 665 } else { 666 kprintf("strategy_xop_write: error %d loff=%016jx\n", 667 error, bp->b_loffset); 668 bp->b_flags |= B_ERROR; 669 bp->b_error = EIO; 670 biodone(bio); 671 } 672 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 673 hammer2_trans_assert_strategy(ip->pmp); 674 hammer2_lwinprog_drop(ip->pmp); 675 hammer2_trans_done(ip->pmp); 676 } 677 678 /* 679 * Wait for pending I/O to complete 680 */ 681 void 682 hammer2_bioq_sync(hammer2_pfs_t *pmp) 683 { 684 hammer2_lwinprog_wait(pmp, 0); 685 } 686 687 /* 688 * Create a new cluster at (cparent, lbase) and assign physical storage, 689 * returning a cluster suitable for I/O. The cluster will be in a modified 690 * state. 691 * 692 * cparent can wind up being anything. 693 * 694 * If datap is not NULL, *datap points to the real data we intend to write. 695 * If we can dedup the storage location we set *datap to NULL to indicate 696 * to the caller that a dedup occurred. 697 * 698 * NOTE: Special case for data embedded in inode. 699 */ 700 static 701 hammer2_chain_t * 702 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 703 hammer2_key_t lbase, int pblksize, 704 hammer2_tid_t mtid, char **datap, int *errorp) 705 { 706 hammer2_chain_t *chain; 707 hammer2_key_t key_dummy; 708 hammer2_off_t dedup_off; 709 int pradix = hammer2_getradix(pblksize); 710 int cache_index = -1; 711 712 /* 713 * Locate the chain associated with lbase, return a locked chain. 714 * However, do not instantiate any data reference (which utilizes a 715 * device buffer) because we will be using direct IO via the 716 * logical buffer cache buffer. 717 */ 718 *errorp = 0; 719 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 720 retry: 721 TIMER(30); 722 chain = hammer2_chain_lookup(parentp, &key_dummy, 723 lbase, lbase, 724 &cache_index, 725 HAMMER2_LOOKUP_NODATA); 726 727 /* 728 * The lookup code should not return a DELETED chain to us, unless 729 * its a short-file embedded in the inode. Then it is possible for 730 * the lookup to return a deleted inode. 731 */ 732 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED) && 733 chain->bref.type != HAMMER2_BREF_TYPE_INODE) { 734 kprintf("assign physical deleted chain @ " 735 "%016jx (%016jx.%02x) ip %016jx\n", 736 lbase, chain->bref.data_off, chain->bref.type, 737 ip->meta.inum); 738 Debugger("bleh"); 739 } 740 741 if (chain == NULL) { 742 /* 743 * We found a hole, create a new chain entry. 744 * 745 * NOTE: DATA chains are created without device backing 746 * store (nor do we want any). 747 */ 748 dedup_off = hammer2_dedup_lookup((*parentp)->hmp, datap, 749 pblksize); 750 *errorp = hammer2_chain_create(parentp, &chain, 751 ip->pmp, 752 HAMMER2_ENC_CHECK(ip->meta.check_algo) | 753 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE), 754 lbase, HAMMER2_PBUFRADIX, 755 HAMMER2_BREF_TYPE_DATA, 756 pblksize, mtid, 757 dedup_off, 0); 758 if (chain == NULL) { 759 panic("hammer2_chain_create: par=%p error=%d\n", 760 *parentp, *errorp); 761 goto retry; 762 } 763 /*ip->delta_dcount += pblksize;*/ 764 } else { 765 switch (chain->bref.type) { 766 case HAMMER2_BREF_TYPE_INODE: 767 /* 768 * The data is embedded in the inode, which requires 769 * a bit more finess. 770 */ 771 hammer2_chain_modify_ip(ip, chain, mtid, 0); 772 break; 773 case HAMMER2_BREF_TYPE_DATA: 774 dedup_off = hammer2_dedup_lookup(chain->hmp, datap, 775 pblksize); 776 if (chain->bytes != pblksize) { 777 hammer2_chain_resize(chain, 778 mtid, dedup_off, 779 pradix, 780 HAMMER2_MODIFY_OPTDATA); 781 } 782 783 /* 784 * DATA buffers must be marked modified whether the 785 * data is in a logical buffer or not. We also have 786 * to make this call to fixup the chain data pointers 787 * after resizing in case this is an encrypted or 788 * compressed buffer. 789 */ 790 hammer2_chain_modify(chain, mtid, dedup_off, 791 HAMMER2_MODIFY_OPTDATA); 792 break; 793 default: 794 panic("hammer2_assign_physical: bad type"); 795 /* NOT REACHED */ 796 break; 797 } 798 } 799 TIMER(31); 800 return (chain); 801 } 802 803 /* 804 * hammer2_write_file_core() - hammer2_write_thread() helper 805 * 806 * The core write function which determines which path to take 807 * depending on compression settings. We also have to locate the 808 * related chains so we can calculate and set the check data for 809 * the blockref. 810 */ 811 static 812 void 813 hammer2_write_file_core(char *data, hammer2_inode_t *ip, 814 hammer2_chain_t **parentp, 815 hammer2_key_t lbase, int ioflag, int pblksize, 816 hammer2_tid_t mtid, int *errorp) 817 { 818 hammer2_chain_t *chain; 819 char *bdata; 820 821 *errorp = 0; 822 823 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 824 case HAMMER2_COMP_NONE: 825 /* 826 * We have to assign physical storage to the buffer 827 * we intend to dirty or write now to avoid deadlocks 828 * in the strategy code later. 829 * 830 * This can return NOOFFSET for inode-embedded data. 831 * The strategy code will take care of it in that case. 832 */ 833 bdata = data; 834 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 835 mtid, &bdata, errorp); 836 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 837 hammer2_inode_data_t *wipdata; 838 839 wipdata = &chain->data->ipdata; 840 KKASSERT(wipdata->meta.op_flags & 841 HAMMER2_OPFLAG_DIRECTDATA); 842 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 843 ++hammer2_iod_file_wembed; 844 } else if (bdata == NULL) { 845 /* 846 * Copy of data already present on-media. 847 */ 848 chain->bref.methods = 849 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 850 HAMMER2_ENC_CHECK(ip->meta.check_algo); 851 hammer2_chain_setcheck(chain, data); 852 } else { 853 hammer2_write_bp(chain, data, ioflag, pblksize, 854 mtid, errorp, ip->meta.check_algo); 855 } 856 if (chain) { 857 hammer2_chain_unlock(chain); 858 hammer2_chain_drop(chain); 859 } 860 break; 861 case HAMMER2_COMP_AUTOZERO: 862 /* 863 * Check for zero-fill only 864 */ 865 hammer2_zero_check_and_write(data, ip, parentp, 866 lbase, ioflag, pblksize, 867 mtid, errorp, 868 ip->meta.check_algo); 869 break; 870 case HAMMER2_COMP_LZ4: 871 case HAMMER2_COMP_ZLIB: 872 default: 873 /* 874 * Check for zero-fill and attempt compression. 875 */ 876 hammer2_compress_and_write(data, ip, parentp, 877 lbase, ioflag, pblksize, 878 mtid, errorp, 879 ip->meta.comp_algo, 880 ip->meta.check_algo); 881 break; 882 } 883 } 884 885 /* 886 * Helper 887 * 888 * Generic function that will perform the compression in compression 889 * write path. The compression algorithm is determined by the settings 890 * obtained from inode. 891 */ 892 static 893 void 894 hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 895 hammer2_chain_t **parentp, 896 hammer2_key_t lbase, int ioflag, int pblksize, 897 hammer2_tid_t mtid, int *errorp, int comp_algo, int check_algo) 898 { 899 hammer2_chain_t *chain; 900 int comp_size; 901 int comp_block_size; 902 char *comp_buffer; 903 char *bdata; 904 905 /* 906 * An all-zeros write creates a hole unless the check code 907 * is disabled. When the check code is disabled all writes 908 * are done in-place, including any all-zeros writes. 909 * 910 * NOTE: A snapshot will still force a copy-on-write 911 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 912 */ 913 if (check_algo != HAMMER2_CHECK_NONE && 914 test_block_zeros(data, pblksize)) { 915 zero_write(data, ip, parentp, lbase, mtid, errorp); 916 return; 917 } 918 919 /* 920 * Compression requested. Try to compress the block. We store 921 * the data normally if we cannot sufficiently compress it. 922 */ 923 comp_size = 0; 924 comp_buffer = NULL; 925 926 KKASSERT(pblksize / 2 <= 32768); 927 928 if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0) { 929 z_stream strm_compress; 930 int comp_level; 931 int ret; 932 933 switch(HAMMER2_DEC_ALGO(comp_algo)) { 934 case HAMMER2_COMP_LZ4: 935 comp_buffer = objcache_get(cache_buffer_write, 936 M_INTWAIT); 937 comp_size = LZ4_compress_limitedOutput( 938 data, 939 &comp_buffer[sizeof(int)], 940 pblksize, 941 pblksize / 2 - sizeof(int)); 942 /* 943 * We need to prefix with the size, LZ4 944 * doesn't do it for us. Add the related 945 * overhead. 946 */ 947 *(int *)comp_buffer = comp_size; 948 if (comp_size) 949 comp_size += sizeof(int); 950 break; 951 case HAMMER2_COMP_ZLIB: 952 comp_level = HAMMER2_DEC_LEVEL(comp_algo); 953 if (comp_level == 0) 954 comp_level = 6; /* default zlib compression */ 955 else if (comp_level < 6) 956 comp_level = 6; 957 else if (comp_level > 9) 958 comp_level = 9; 959 ret = deflateInit(&strm_compress, comp_level); 960 if (ret != Z_OK) { 961 kprintf("HAMMER2 ZLIB: fatal error " 962 "on deflateInit.\n"); 963 } 964 965 comp_buffer = objcache_get(cache_buffer_write, 966 M_INTWAIT); 967 strm_compress.next_in = data; 968 strm_compress.avail_in = pblksize; 969 strm_compress.next_out = comp_buffer; 970 strm_compress.avail_out = pblksize / 2; 971 ret = deflate(&strm_compress, Z_FINISH); 972 if (ret == Z_STREAM_END) { 973 comp_size = pblksize / 2 - 974 strm_compress.avail_out; 975 } else { 976 comp_size = 0; 977 } 978 ret = deflateEnd(&strm_compress); 979 break; 980 default: 981 kprintf("Error: Unknown compression method.\n"); 982 kprintf("Comp_method = %d.\n", comp_algo); 983 break; 984 } 985 } 986 987 if (comp_size == 0) { 988 /* 989 * compression failed or turned off 990 */ 991 comp_block_size = pblksize; /* safety */ 992 if (++ip->comp_heuristic > 128) 993 ip->comp_heuristic = 8; 994 } else { 995 /* 996 * compression succeeded 997 */ 998 ip->comp_heuristic = 0; 999 if (comp_size <= 1024) { 1000 comp_block_size = 1024; 1001 } else if (comp_size <= 2048) { 1002 comp_block_size = 2048; 1003 } else if (comp_size <= 4096) { 1004 comp_block_size = 4096; 1005 } else if (comp_size <= 8192) { 1006 comp_block_size = 8192; 1007 } else if (comp_size <= 16384) { 1008 comp_block_size = 16384; 1009 } else if (comp_size <= 32768) { 1010 comp_block_size = 32768; 1011 } else { 1012 panic("hammer2: WRITE PATH: " 1013 "Weird comp_size value."); 1014 /* NOT REACHED */ 1015 comp_block_size = pblksize; 1016 } 1017 1018 /* 1019 * Must zero the remainder or dedup (which operates on a 1020 * physical block basis) will not find matches. 1021 */ 1022 if (comp_size < comp_block_size) { 1023 bzero(comp_buffer + comp_size, 1024 comp_block_size - comp_size); 1025 } 1026 } 1027 1028 /* 1029 * Assign physical storage, data will be set to NULL if a live-dedup 1030 * was successful. 1031 */ 1032 bdata = comp_size ? comp_buffer : data; 1033 chain = hammer2_assign_physical(ip, parentp, lbase, comp_block_size, 1034 mtid, &bdata, errorp); 1035 1036 if (*errorp) { 1037 kprintf("WRITE PATH: An error occurred while " 1038 "assigning physical space.\n"); 1039 KKASSERT(chain == NULL); 1040 goto done; 1041 } 1042 1043 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1044 hammer2_inode_data_t *wipdata; 1045 1046 hammer2_chain_modify_ip(ip, chain, mtid, 0); 1047 wipdata = &chain->data->ipdata; 1048 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1049 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1050 ++hammer2_iod_file_wembed; 1051 } else if (bdata == NULL) { 1052 /* 1053 * Live deduplication, a copy of the data is already present 1054 * on the media. 1055 */ 1056 if (comp_size) { 1057 chain->bref.methods = 1058 HAMMER2_ENC_COMP(comp_algo) + 1059 HAMMER2_ENC_CHECK(check_algo); 1060 } else { 1061 chain->bref.methods = 1062 HAMMER2_ENC_COMP( 1063 HAMMER2_COMP_NONE) + 1064 HAMMER2_ENC_CHECK(check_algo); 1065 } 1066 bdata = comp_size ? comp_buffer : data; 1067 hammer2_chain_setcheck(chain, bdata); 1068 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1069 } else { 1070 hammer2_io_t *dio; 1071 1072 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1073 1074 switch(chain->bref.type) { 1075 case HAMMER2_BREF_TYPE_INODE: 1076 panic("hammer2_write_bp: unexpected inode\n"); 1077 break; 1078 case HAMMER2_BREF_TYPE_DATA: 1079 /* 1080 * Optimize out the read-before-write 1081 * if possible. 1082 */ 1083 *errorp = hammer2_io_newnz(chain->hmp, 1084 chain->bref.type, 1085 chain->bref.data_off, 1086 chain->bytes, 1087 &dio); 1088 if (*errorp) { 1089 hammer2_io_brelse(&dio); 1090 kprintf("hammer2: WRITE PATH: " 1091 "dbp bread error\n"); 1092 break; 1093 } 1094 bdata = hammer2_io_data(dio, chain->bref.data_off); 1095 1096 /* 1097 * When loading the block make sure we don't 1098 * leave garbage after the compressed data. 1099 */ 1100 if (comp_size) { 1101 chain->bref.methods = 1102 HAMMER2_ENC_COMP(comp_algo) + 1103 HAMMER2_ENC_CHECK(check_algo); 1104 bcopy(comp_buffer, bdata, comp_size); 1105 } else { 1106 chain->bref.methods = 1107 HAMMER2_ENC_COMP( 1108 HAMMER2_COMP_NONE) + 1109 HAMMER2_ENC_CHECK(check_algo); 1110 bcopy(data, bdata, pblksize); 1111 } 1112 1113 /* 1114 * The flush code doesn't calculate check codes for 1115 * file data (doing so can result in excessive I/O), 1116 * so we do it here. 1117 */ 1118 hammer2_chain_setcheck(chain, bdata); 1119 hammer2_dedup_record(chain, bdata); 1120 1121 /* 1122 * Device buffer is now valid, chain is no longer in 1123 * the initial state. 1124 * 1125 * (No blockref table worries with file data) 1126 */ 1127 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1128 1129 /* Now write the related bdp. */ 1130 if (ioflag & IO_SYNC) { 1131 /* 1132 * Synchronous I/O requested. 1133 */ 1134 hammer2_io_bwrite(&dio); 1135 /* 1136 } else if ((ioflag & IO_DIRECT) && 1137 loff + n == pblksize) { 1138 hammer2_io_bdwrite(&dio); 1139 */ 1140 } else if (ioflag & IO_ASYNC) { 1141 hammer2_io_bawrite(&dio); 1142 } else { 1143 hammer2_io_bdwrite(&dio); 1144 } 1145 break; 1146 default: 1147 panic("hammer2_write_bp: bad chain type %d\n", 1148 chain->bref.type); 1149 /* NOT REACHED */ 1150 break; 1151 } 1152 } 1153 done: 1154 if (chain) { 1155 hammer2_chain_unlock(chain); 1156 hammer2_chain_drop(chain); 1157 } 1158 if (comp_buffer) 1159 objcache_put(cache_buffer_write, comp_buffer); 1160 } 1161 1162 /* 1163 * Helper 1164 * 1165 * Function that performs zero-checking and writing without compression, 1166 * it corresponds to default zero-checking path. 1167 */ 1168 static 1169 void 1170 hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 1171 hammer2_chain_t **parentp, 1172 hammer2_key_t lbase, int ioflag, int pblksize, 1173 hammer2_tid_t mtid, int *errorp, 1174 int check_algo) 1175 { 1176 hammer2_chain_t *chain; 1177 1178 if (check_algo != HAMMER2_CHECK_NONE && 1179 test_block_zeros(data, pblksize)) { 1180 /* 1181 * An all-zeros write creates a hole unless the check code 1182 * is disabled. When the check code is disabled all writes 1183 * are done in-place, including any all-zeros writes. 1184 * 1185 * NOTE: A snapshot will still force a copy-on-write 1186 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 1187 */ 1188 zero_write(data, ip, parentp, lbase, mtid, errorp); 1189 } else { 1190 /* 1191 * Normal write 1192 */ 1193 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 1194 mtid, &data, errorp); 1195 if (data) { 1196 hammer2_write_bp(chain, data, ioflag, pblksize, 1197 mtid, errorp, check_algo); 1198 } /* else dedup occurred */ 1199 if (chain) { 1200 hammer2_chain_unlock(chain); 1201 hammer2_chain_drop(chain); 1202 } 1203 } 1204 } 1205 1206 /* 1207 * Helper 1208 * 1209 * A function to test whether a block of data contains only zeros, 1210 * returns TRUE (non-zero) if the block is all zeros. 1211 */ 1212 static 1213 int 1214 test_block_zeros(const char *buf, size_t bytes) 1215 { 1216 size_t i; 1217 1218 for (i = 0; i < bytes; i += sizeof(long)) { 1219 if (*(const long *)(buf + i) != 0) 1220 return (0); 1221 } 1222 return (1); 1223 } 1224 1225 /* 1226 * Helper 1227 * 1228 * Function to "write" a block that contains only zeros. 1229 */ 1230 static 1231 void 1232 zero_write(char *data, hammer2_inode_t *ip, 1233 hammer2_chain_t **parentp, 1234 hammer2_key_t lbase, hammer2_tid_t mtid, int *errorp) 1235 { 1236 hammer2_chain_t *chain; 1237 hammer2_key_t key_dummy; 1238 int cache_index = -1; 1239 1240 *errorp = 0; 1241 chain = hammer2_chain_lookup(parentp, &key_dummy, 1242 lbase, lbase, 1243 &cache_index, 1244 HAMMER2_LOOKUP_NODATA); 1245 if (chain) { 1246 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1247 hammer2_inode_data_t *wipdata; 1248 1249 hammer2_chain_modify_ip(ip, chain, mtid, 0); 1250 wipdata = &chain->data->ipdata; 1251 KKASSERT(wipdata->meta.op_flags & 1252 HAMMER2_OPFLAG_DIRECTDATA); 1253 bzero(wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1254 ++hammer2_iod_file_wembed; 1255 } else { 1256 hammer2_chain_delete(*parentp, chain, 1257 mtid, HAMMER2_DELETE_PERMANENT); 1258 ++hammer2_iod_file_wzero; 1259 } 1260 hammer2_chain_unlock(chain); 1261 hammer2_chain_drop(chain); 1262 } else { 1263 ++hammer2_iod_file_wzero; 1264 } 1265 } 1266 1267 /* 1268 * Helper 1269 * 1270 * Function to write the data as it is, without performing any sort of 1271 * compression. This function is used in path without compression and 1272 * default zero-checking path. 1273 */ 1274 static 1275 void 1276 hammer2_write_bp(hammer2_chain_t *chain, char *data, int ioflag, 1277 int pblksize, 1278 hammer2_tid_t mtid, int *errorp, int check_algo) 1279 { 1280 hammer2_inode_data_t *wipdata; 1281 hammer2_io_t *dio; 1282 char *bdata; 1283 int error; 1284 1285 error = 0; /* XXX TODO below */ 1286 1287 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1288 1289 switch(chain->bref.type) { 1290 case HAMMER2_BREF_TYPE_INODE: 1291 wipdata = &chain->data->ipdata; 1292 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1293 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1294 error = 0; 1295 ++hammer2_iod_file_wembed; 1296 break; 1297 case HAMMER2_BREF_TYPE_DATA: 1298 error = hammer2_io_newnz(chain->hmp, 1299 chain->bref.type, 1300 chain->bref.data_off, 1301 chain->bytes, &dio); 1302 if (error) { 1303 hammer2_io_bqrelse(&dio); 1304 kprintf("hammer2: WRITE PATH: " 1305 "dbp bread error\n"); 1306 break; 1307 } 1308 bdata = hammer2_io_data(dio, chain->bref.data_off); 1309 1310 chain->bref.methods = HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1311 HAMMER2_ENC_CHECK(check_algo); 1312 bcopy(data, bdata, chain->bytes); 1313 1314 /* 1315 * The flush code doesn't calculate check codes for 1316 * file data (doing so can result in excessive I/O), 1317 * so we do it here. 1318 */ 1319 hammer2_chain_setcheck(chain, bdata); 1320 hammer2_dedup_record(chain, bdata); 1321 1322 /* 1323 * Device buffer is now valid, chain is no longer in 1324 * the initial state. 1325 * 1326 * (No blockref table worries with file data) 1327 */ 1328 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1329 1330 if (ioflag & IO_SYNC) { 1331 /* 1332 * Synchronous I/O requested. 1333 */ 1334 hammer2_io_bwrite(&dio); 1335 /* 1336 } else if ((ioflag & IO_DIRECT) && 1337 loff + n == pblksize) { 1338 hammer2_io_bdwrite(&dio); 1339 */ 1340 } else if (ioflag & IO_ASYNC) { 1341 hammer2_io_bawrite(&dio); 1342 } else { 1343 hammer2_io_bdwrite(&dio); 1344 } 1345 break; 1346 default: 1347 panic("hammer2_write_bp: bad chain type %d\n", 1348 chain->bref.type); 1349 /* NOT REACHED */ 1350 error = 0; 1351 break; 1352 } 1353 KKASSERT(error == 0); /* XXX TODO */ 1354 *errorp = error; 1355 } 1356 1357 /* 1358 * LIVE DEDUP HEURISTIC 1359 * 1360 * WARNING! This code is SMP safe but the heuristic allows SMP collisions. 1361 * All fields must be loaded into locals and validated. 1362 * 1363 * WARNING! Should only be used for file data, hammer2_chain_modify() only 1364 * checks for the dedup case on data chains. Also, dedup data can 1365 * only be recorded for committed chains (so NOT strategy writes 1366 * which can undergo further modification after the fact!). 1367 */ 1368 void 1369 hammer2_dedup_record(hammer2_chain_t *chain, char *data) 1370 { 1371 hammer2_dev_t *hmp; 1372 hammer2_dedup_t *dedup; 1373 uint64_t crc; 1374 int best = 0; 1375 int i; 1376 int dticks; 1377 1378 if (hammer2_dedup_enable == 0) 1379 return; 1380 1381 /* 1382 * Only committed data can be recorded for de-duplication, otherwise 1383 * the contents may change out from under us. So, on read if the 1384 * chain is not modified, and on flush when the chain is committed. 1385 */ 1386 if ((chain->flags & 1387 (HAMMER2_CHAIN_MODIFIED | HAMMER2_CHAIN_INITIAL)) == 0) { 1388 return; 1389 } 1390 1391 1392 hmp = chain->hmp; 1393 1394 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 1395 case HAMMER2_CHECK_ISCSI32: 1396 /* 1397 * XXX use the built-in crc (the dedup lookup sequencing 1398 * needs to be fixed so the check code is already present 1399 * when dedup_lookup is called) 1400 */ 1401 #if 0 1402 crc = (uint64_t)(uint32_t)chain->bref.check.iscsi32.value; 1403 #endif 1404 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1405 break; 1406 case HAMMER2_CHECK_XXHASH64: 1407 crc = chain->bref.check.xxhash64.value; 1408 break; 1409 case HAMMER2_CHECK_SHA192: 1410 /* 1411 * XXX use the built-in crc (the dedup lookup sequencing 1412 * needs to be fixed so the check code is already present 1413 * when dedup_lookup is called) 1414 */ 1415 #if 0 1416 crc = ((uint64_t *)chain->bref.check.sha192.data)[0] ^ 1417 ((uint64_t *)chain->bref.check.sha192.data)[1] ^ 1418 ((uint64_t *)chain->bref.check.sha192.data)[2]; 1419 #endif 1420 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1421 break; 1422 default: 1423 /* 1424 * Cannot dedup without a check code 1425 * 1426 * NOTE: In particular, CHECK_NONE allows a sector to be 1427 * overwritten without copy-on-write, recording 1428 * a dedup block for a CHECK_NONE object would be 1429 * a disaster! 1430 */ 1431 return; 1432 } 1433 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1434 for (i = 0; i < 4; ++i) { 1435 if (dedup[i].data_crc == crc) { 1436 best = i; 1437 break; 1438 } 1439 dticks = (int)(dedup[i].ticks - dedup[best].ticks); 1440 if (dticks < 0 || dticks > hz * 60 * 30) 1441 best = i; 1442 } 1443 dedup += best; 1444 if (hammer2_debug & 0x40000) { 1445 kprintf("REC %04x %016jx %016jx\n", 1446 (int)(dedup - hmp->heur_dedup), 1447 crc, 1448 chain->bref.data_off); 1449 } 1450 dedup->ticks = ticks; 1451 dedup->data_off = chain->bref.data_off; 1452 dedup->data_crc = crc; 1453 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DEDUP); 1454 } 1455 1456 static 1457 hammer2_off_t 1458 hammer2_dedup_lookup(hammer2_dev_t *hmp, char **datap, int pblksize) 1459 { 1460 hammer2_dedup_t *dedup; 1461 hammer2_io_t *dio; 1462 hammer2_off_t off; 1463 uint64_t crc; 1464 char *data; 1465 int i; 1466 1467 if (hammer2_dedup_enable == 0) 1468 return 0; 1469 data = *datap; 1470 if (data == NULL) 1471 return 0; 1472 1473 /* 1474 * XXX use the built-in crc (the dedup lookup sequencing 1475 * needs to be fixed so the check code is already present 1476 * when dedup_lookup is called) 1477 */ 1478 crc = XXH64(data, pblksize, XXH_HAMMER2_SEED); 1479 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1480 1481 if (hammer2_debug & 0x40000) { 1482 kprintf("LOC %04x/4 %016jx\n", 1483 (int)(dedup - hmp->heur_dedup), 1484 crc); 1485 } 1486 1487 for (i = 0; i < 4; ++i) { 1488 off = dedup[i].data_off; 1489 cpu_ccfence(); 1490 if (dedup[i].data_crc != crc) 1491 continue; 1492 if ((1 << (int)(off & HAMMER2_OFF_MASK_RADIX)) != pblksize) 1493 continue; 1494 dio = hammer2_io_getquick(hmp, off, pblksize); 1495 if (dio && 1496 bcmp(data, hammer2_io_data(dio, off), pblksize) == 0) { 1497 /* 1498 * Make sure the INVALOK flag is cleared to prevent 1499 * the possibly-dirty bp from being invalidated now 1500 * that we are using it as part of a de-dup operation. 1501 */ 1502 if (hammer2_debug & 0x40000) { 1503 kprintf("DEDUP SUCCESS %016jx\n", 1504 (intmax_t)off); 1505 } 1506 atomic_clear_64(&dio->refs, HAMMER2_DIO_INVALOK); 1507 hammer2_io_putblk(&dio); 1508 *datap = NULL; 1509 dedup[i].ticks = ticks; /* update use */ 1510 ++hammer2_iod_file_wdedup; 1511 1512 return off; /* RETURN */ 1513 } 1514 if (dio) 1515 hammer2_io_putblk(&dio); 1516 } 1517 return 0; 1518 } 1519 1520 /* 1521 * Poof. Races are ok, if someone gets in and reuses a dedup offset 1522 * before or while we are clearing it they will also recover the freemap 1523 * entry (set it to fully allocated), so a bulkfree race can only set it 1524 * to a possibly-free state. 1525 * 1526 * XXX ok, well, not really sure races are ok but going to run with it 1527 * for the moment. 1528 */ 1529 void 1530 hammer2_dedup_clear(hammer2_dev_t *hmp) 1531 { 1532 int i; 1533 1534 for (i = 0; i < HAMMER2_DEDUP_HEUR_SIZE; ++i) { 1535 hmp->heur_dedup[i].data_off = 0; 1536 hmp->heur_dedup[i].ticks = ticks - 1; 1537 } 1538 } 1539