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 99 hammer2_vop_strategy(struct vop_strategy_args *ap) 100 { 101 struct bio *biop; 102 struct buf *bp; 103 int error; 104 105 biop = ap->a_bio; 106 bp = biop->bio_buf; 107 108 switch(bp->b_cmd) { 109 case BUF_CMD_READ: 110 error = hammer2_strategy_read(ap); 111 ++hammer2_iod_file_read; 112 break; 113 case BUF_CMD_WRITE: 114 error = hammer2_strategy_write(ap); 115 ++hammer2_iod_file_write; 116 break; 117 default: 118 bp->b_error = error = EINVAL; 119 bp->b_flags |= B_ERROR; 120 biodone(biop); 121 break; 122 } 123 return (error); 124 } 125 126 /* 127 * Return the largest contiguous physical disk range for the logical 128 * request, in bytes. 129 * 130 * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb) 131 * 132 * Basically disabled, the logical buffer write thread has to deal with 133 * buffers one-at-a-time. Note that this should not prevent cluster_read() 134 * from reading-ahead, it simply prevents it from trying form a single 135 * cluster buffer for the logical request. H2 already uses 64KB buffers! 136 */ 137 int 138 hammer2_vop_bmap(struct vop_bmap_args *ap) 139 { 140 *ap->a_doffsetp = NOOFFSET; 141 if (ap->a_runp) 142 *ap->a_runp = 0; 143 if (ap->a_runb) 144 *ap->a_runb = 0; 145 return (EOPNOTSUPP); 146 } 147 148 /**************************************************************************** 149 * READ SUPPORT * 150 ****************************************************************************/ 151 /* 152 * Callback used in read path in case that a block is compressed with LZ4. 153 */ 154 static 155 void 156 hammer2_decompress_LZ4_callback(const char *data, u_int bytes, struct bio *bio) 157 { 158 struct buf *bp; 159 char *compressed_buffer; 160 int compressed_size; 161 int result; 162 163 bp = bio->bio_buf; 164 165 #if 0 166 if bio->bio_caller_info2.index && 167 bio->bio_caller_info1.uvalue32 != 168 crc32(bp->b_data, bp->b_bufsize) --- return error 169 #endif 170 171 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 172 compressed_size = *(const int *)data; 173 KKASSERT((uint32_t)compressed_size <= bytes - sizeof(int)); 174 175 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 176 result = LZ4_decompress_safe(__DECONST(char *, &data[sizeof(int)]), 177 compressed_buffer, 178 compressed_size, 179 bp->b_bufsize); 180 if (result < 0) { 181 kprintf("READ PATH: Error during decompression." 182 "bio %016jx/%d\n", 183 (intmax_t)bio->bio_offset, bytes); 184 /* make sure it isn't random garbage */ 185 bzero(compressed_buffer, bp->b_bufsize); 186 } 187 KKASSERT(result <= bp->b_bufsize); 188 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 189 if (result < bp->b_bufsize) 190 bzero(bp->b_data + result, bp->b_bufsize - result); 191 objcache_put(cache_buffer_read, compressed_buffer); 192 bp->b_resid = 0; 193 bp->b_flags |= B_AGE; 194 } 195 196 /* 197 * Callback used in read path in case that a block is compressed with ZLIB. 198 * It is almost identical to LZ4 callback, so in theory they can be unified, 199 * but we didn't want to make changes in bio structure for that. 200 */ 201 static 202 void 203 hammer2_decompress_ZLIB_callback(const char *data, u_int bytes, struct bio *bio) 204 { 205 struct buf *bp; 206 char *compressed_buffer; 207 z_stream strm_decompress; 208 int result; 209 int ret; 210 211 bp = bio->bio_buf; 212 213 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 214 strm_decompress.avail_in = 0; 215 strm_decompress.next_in = Z_NULL; 216 217 ret = inflateInit(&strm_decompress); 218 219 if (ret != Z_OK) 220 kprintf("HAMMER2 ZLIB: Fatal error in inflateInit.\n"); 221 222 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 223 strm_decompress.next_in = __DECONST(char *, data); 224 225 /* XXX supply proper size, subset of device bp */ 226 strm_decompress.avail_in = bytes; 227 strm_decompress.next_out = compressed_buffer; 228 strm_decompress.avail_out = bp->b_bufsize; 229 230 ret = inflate(&strm_decompress, Z_FINISH); 231 if (ret != Z_STREAM_END) { 232 kprintf("HAMMER2 ZLIB: Fatar error during decompression.\n"); 233 bzero(compressed_buffer, bp->b_bufsize); 234 } 235 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 236 result = bp->b_bufsize - strm_decompress.avail_out; 237 if (result < bp->b_bufsize) 238 bzero(bp->b_data + result, strm_decompress.avail_out); 239 objcache_put(cache_buffer_read, compressed_buffer); 240 ret = inflateEnd(&strm_decompress); 241 242 bp->b_resid = 0; 243 bp->b_flags |= B_AGE; 244 } 245 246 /* 247 * Logical buffer I/O, async read. 248 */ 249 static 250 int 251 hammer2_strategy_read(struct vop_strategy_args *ap) 252 { 253 hammer2_xop_strategy_t *xop; 254 struct buf *bp; 255 struct bio *bio; 256 struct bio *nbio; 257 hammer2_inode_t *ip; 258 hammer2_key_t lbase; 259 260 bio = ap->a_bio; 261 bp = bio->bio_buf; 262 ip = VTOI(ap->a_vp); 263 nbio = push_bio(bio); 264 265 lbase = bio->bio_offset; 266 KKASSERT(((int)lbase & HAMMER2_PBUFMASK) == 0); 267 268 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_STRATEGY); 269 xop->finished = 0; 270 xop->bio = bio; 271 xop->lbase = lbase; 272 hammer2_mtx_init(&xop->lock, "h2bior"); 273 hammer2_xop_start(&xop->head, hammer2_strategy_xop_read); 274 /* asynchronous completion */ 275 276 return(0); 277 } 278 279 /* 280 * Per-node XOP (threaded), do a synchronous lookup of the chain and 281 * its data. The frontend is asynchronous, so we are also responsible 282 * for racing to terminate the frontend. 283 */ 284 static 285 void 286 hammer2_strategy_xop_read(hammer2_thread_t *thr, hammer2_xop_t *arg) 287 { 288 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 289 hammer2_chain_t *parent; 290 hammer2_chain_t *chain; 291 hammer2_key_t key_dummy; 292 hammer2_key_t lbase; 293 struct bio *bio; 294 struct buf *bp; 295 int error; 296 297 /* 298 * Note that we can race completion of the bio supplied by 299 * the front-end so we cannot access it until we determine 300 * that we are the ones finishing it up. 301 */ 302 lbase = xop->lbase; 303 304 /* 305 * This is difficult to optimize. The logical buffer might be 306 * partially dirty (contain dummy zero-fill pages), which would 307 * mess up our crc calculation if we were to try a direct read. 308 * So for now we always double-buffer through the underlying 309 * storage. 310 * 311 * If not for the above problem we could conditionalize on 312 * (1) 64KB buffer, (2) one chain (not multi-master) and 313 * (3) !hammer2_double_buffer, and issue a direct read into the 314 * logical buffer. 315 */ 316 parent = hammer2_inode_chain(xop->head.ip1, thr->clindex, 317 HAMMER2_RESOLVE_ALWAYS | 318 HAMMER2_RESOLVE_SHARED); 319 if (parent) { 320 chain = hammer2_chain_lookup(&parent, &key_dummy, 321 lbase, lbase, 322 &error, 323 HAMMER2_LOOKUP_ALWAYS | 324 HAMMER2_LOOKUP_SHARED); 325 if (chain) 326 error = chain->error; 327 error = hammer2_error_to_errno(error); 328 } else { 329 error = EIO; 330 chain = NULL; 331 } 332 error = hammer2_xop_feed(&xop->head, chain, thr->clindex, error); 333 if (chain) { 334 hammer2_chain_unlock(chain); 335 hammer2_chain_drop(chain); 336 } 337 if (parent) { 338 hammer2_chain_unlock(parent); 339 hammer2_chain_drop(parent); 340 } 341 chain = NULL; /* safety */ 342 parent = NULL; /* safety */ 343 344 /* 345 * Race to finish the frontend. First-to-complete. bio is only 346 * valid if we are determined to be the ones able to complete 347 * the operation. 348 */ 349 if (xop->finished) 350 return; 351 hammer2_mtx_ex(&xop->lock); 352 if (xop->finished) { 353 hammer2_mtx_unlock(&xop->lock); 354 return; 355 } 356 bio = xop->bio; 357 bp = bio->bio_buf; 358 359 /* 360 * Async operation has not completed and we now own the lock. 361 * Determine if we can complete the operation by issuing the 362 * frontend collection non-blocking. 363 * 364 * H2 double-buffers the data, setting B_NOTMETA on the logical 365 * buffer hints to the OS that the logical buffer should not be 366 * swapcached (since the device buffer can be). 367 * 368 * Also note that even for compressed data we would rather the 369 * kernel cache/swapcache device buffers more and (decompressed) 370 * logical buffers less, since that will significantly improve 371 * the amount of end-user data that can be cached. 372 */ 373 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 374 375 switch(error) { 376 case 0: 377 xop->finished = 1; 378 hammer2_mtx_unlock(&xop->lock); 379 bp->b_flags |= B_NOTMETA; 380 chain = xop->head.cluster.focus; 381 hammer2_strategy_read_completion(chain, (char *)chain->data, 382 xop->bio); 383 biodone(bio); 384 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 385 break; 386 case ENOENT: 387 xop->finished = 1; 388 hammer2_mtx_unlock(&xop->lock); 389 bp->b_flags |= B_NOTMETA; 390 bp->b_resid = 0; 391 bp->b_error = 0; 392 bzero(bp->b_data, bp->b_bcount); 393 biodone(bio); 394 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 395 break; 396 case EINPROGRESS: 397 hammer2_mtx_unlock(&xop->lock); 398 break; 399 default: 400 kprintf("strategy_xop_read: error %d loff=%016jx\n", 401 error, bp->b_loffset); 402 xop->finished = 1; 403 hammer2_mtx_unlock(&xop->lock); 404 bp->b_flags |= B_ERROR; 405 bp->b_error = EIO; 406 biodone(bio); 407 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 408 break; 409 } 410 } 411 412 static 413 void 414 hammer2_strategy_read_completion(hammer2_chain_t *chain, char *data, 415 struct bio *bio) 416 { 417 struct buf *bp = bio->bio_buf; 418 419 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 420 /* 421 * Copy from in-memory inode structure. 422 */ 423 bcopy(((hammer2_inode_data_t *)data)->u.data, 424 bp->b_data, HAMMER2_EMBEDDED_BYTES); 425 bzero(bp->b_data + HAMMER2_EMBEDDED_BYTES, 426 bp->b_bcount - HAMMER2_EMBEDDED_BYTES); 427 bp->b_resid = 0; 428 bp->b_error = 0; 429 } else if (chain->bref.type == HAMMER2_BREF_TYPE_DATA) { 430 /* 431 * Data is on-media, record for live dedup. Release the 432 * chain (try to free it) when done. The data is still 433 * cached by both the buffer cache in front and the 434 * block device behind us. This leaves more room in the 435 * LRU chain cache for meta-data chains which we really 436 * want to retain. 437 * 438 * NOTE: Deduplication cannot be safely recorded for 439 * records without a check code. 440 */ 441 hammer2_dedup_record(chain, NULL, data); 442 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE); 443 444 /* 445 * Decompression and copy. 446 */ 447 switch (HAMMER2_DEC_COMP(chain->bref.methods)) { 448 case HAMMER2_COMP_LZ4: 449 hammer2_decompress_LZ4_callback(data, chain->bytes, 450 bio); 451 /* b_resid set by call */ 452 break; 453 case HAMMER2_COMP_ZLIB: 454 hammer2_decompress_ZLIB_callback(data, chain->bytes, 455 bio); 456 /* b_resid set by call */ 457 break; 458 case HAMMER2_COMP_NONE: 459 KKASSERT(chain->bytes <= bp->b_bcount); 460 bcopy(data, bp->b_data, chain->bytes); 461 if (chain->bytes < bp->b_bcount) { 462 bzero(bp->b_data + chain->bytes, 463 bp->b_bcount - chain->bytes); 464 } 465 bp->b_resid = 0; 466 bp->b_error = 0; 467 break; 468 default: 469 panic("hammer2_strategy_read: " 470 "unknown compression type"); 471 } 472 } else { 473 panic("hammer2_strategy_read: unknown bref type"); 474 } 475 } 476 477 /**************************************************************************** 478 * WRITE SUPPORT * 479 ****************************************************************************/ 480 481 /* 482 * Functions for compression in threads, 483 * from hammer2_vnops.c 484 */ 485 static void hammer2_write_file_core(char *data, hammer2_inode_t *ip, 486 hammer2_chain_t **parentp, 487 hammer2_key_t lbase, int ioflag, int pblksize, 488 hammer2_tid_t mtid, int *errorp); 489 static void hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 490 hammer2_chain_t **parentp, 491 hammer2_key_t lbase, int ioflag, int pblksize, 492 hammer2_tid_t mtid, int *errorp, 493 int comp_algo, int check_algo); 494 static void hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 495 hammer2_chain_t **parentp, 496 hammer2_key_t lbase, int ioflag, int pblksize, 497 hammer2_tid_t mtid, int *errorp, 498 int check_algo); 499 static int test_block_zeros(const char *buf, size_t bytes); 500 static void zero_write(char *data, hammer2_inode_t *ip, 501 hammer2_chain_t **parentp, 502 hammer2_key_t lbase, 503 hammer2_tid_t mtid, int *errorp); 504 static void hammer2_write_bp(hammer2_chain_t *chain, char *data, 505 int ioflag, int pblksize, 506 hammer2_tid_t mtid, int *errorp, 507 int check_algo); 508 509 static 510 int 511 hammer2_strategy_write(struct vop_strategy_args *ap) 512 { 513 hammer2_xop_strategy_t *xop; 514 hammer2_pfs_t *pmp; 515 struct bio *bio; 516 struct buf *bp; 517 hammer2_inode_t *ip; 518 519 bio = ap->a_bio; 520 bp = bio->bio_buf; 521 ip = VTOI(ap->a_vp); 522 pmp = ip->pmp; 523 524 hammer2_lwinprog_ref(pmp); 525 hammer2_trans_assert_strategy(pmp); 526 hammer2_trans_init(pmp, HAMMER2_TRANS_BUFCACHE); 527 528 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING | 529 HAMMER2_XOP_STRATEGY); 530 xop->finished = 0; 531 xop->bio = bio; 532 xop->lbase = bio->bio_offset; 533 hammer2_mtx_init(&xop->lock, "h2biow"); 534 hammer2_xop_start(&xop->head, hammer2_strategy_xop_write); 535 /* asynchronous completion */ 536 537 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 538 539 return(0); 540 } 541 542 /* 543 * Per-node XOP (threaded). Write the logical buffer to the media. 544 * 545 * This is a bit problematic because there may be multiple target and 546 * any of them may be able to release the bp. In addition, if our 547 * particulr target is offline we don't want to block the bp (and thus 548 * the frontend). To accomplish this we copy the data to the per-thr 549 * scratch buffer. 550 */ 551 static 552 void 553 hammer2_strategy_xop_write(hammer2_thread_t *thr, hammer2_xop_t *arg) 554 { 555 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 556 hammer2_chain_t *parent; 557 hammer2_key_t lbase; 558 hammer2_inode_t *ip; 559 struct bio *bio; 560 struct buf *bp; 561 int error; 562 int lblksize; 563 int pblksize; 564 hammer2_off_t bio_offset; 565 char *bio_data; 566 567 /* 568 * We can only access the bp/bio if the frontend has not yet 569 * completed. 570 */ 571 if (xop->finished) 572 return; 573 hammer2_mtx_sh(&xop->lock); 574 if (xop->finished) { 575 hammer2_mtx_unlock(&xop->lock); 576 return; 577 } 578 579 lbase = xop->lbase; 580 bio = xop->bio; /* ephermal */ 581 bp = bio->bio_buf; /* ephermal */ 582 ip = xop->head.ip1; /* retained by ref */ 583 bio_offset = bio->bio_offset; 584 bio_data = thr->scratch; 585 586 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 587 588 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 589 pblksize = hammer2_calc_physical(ip, lbase); 590 bcopy(bp->b_data, bio_data, lblksize); 591 592 hammer2_mtx_unlock(&xop->lock); 593 bp = NULL; /* safety, illegal to access after unlock */ 594 bio = NULL; /* safety, illegal to access after unlock */ 595 596 /* 597 * Actual operation 598 */ 599 parent = hammer2_inode_chain(ip, thr->clindex, HAMMER2_RESOLVE_ALWAYS); 600 hammer2_write_file_core(bio_data, ip, &parent, 601 lbase, IO_ASYNC, pblksize, 602 xop->head.mtid, &error); 603 error = hammer2_error_to_errno(error); 604 if (parent) { 605 hammer2_chain_unlock(parent); 606 hammer2_chain_drop(parent); 607 parent = NULL; /* safety */ 608 } 609 hammer2_xop_feed(&xop->head, NULL, thr->clindex, error); 610 611 /* 612 * Try to complete the operation on behalf of the front-end. 613 */ 614 if (xop->finished) 615 return; 616 hammer2_mtx_ex(&xop->lock); 617 if (xop->finished) { 618 hammer2_mtx_unlock(&xop->lock); 619 return; 620 } 621 622 /* 623 * Async operation has not completed and we now own the lock. 624 * Determine if we can complete the operation by issuing the 625 * frontend collection non-blocking. 626 * 627 * H2 double-buffers the data, setting B_NOTMETA on the logical 628 * buffer hints to the OS that the logical buffer should not be 629 * swapcached (since the device buffer can be). 630 */ 631 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 632 633 if (error == EINPROGRESS) { 634 hammer2_mtx_unlock(&xop->lock); 635 return; 636 } 637 638 /* 639 * Async operation has completed. 640 */ 641 xop->finished = 1; 642 hammer2_mtx_unlock(&xop->lock); 643 644 bio = xop->bio; /* now owned by us */ 645 bp = bio->bio_buf; /* now owned by us */ 646 647 if (error == ENOENT || error == 0) { 648 bp->b_flags |= B_NOTMETA; 649 bp->b_resid = 0; 650 bp->b_error = 0; 651 biodone(bio); 652 } else { 653 kprintf("strategy_xop_write: error %d loff=%016jx\n", 654 error, bp->b_loffset); 655 bp->b_flags |= B_ERROR; 656 bp->b_error = EIO; 657 biodone(bio); 658 } 659 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 660 hammer2_trans_assert_strategy(ip->pmp); 661 hammer2_lwinprog_drop(ip->pmp); 662 hammer2_trans_done(ip->pmp); 663 } 664 665 /* 666 * Wait for pending I/O to complete 667 */ 668 void 669 hammer2_bioq_sync(hammer2_pfs_t *pmp) 670 { 671 hammer2_lwinprog_wait(pmp, 0); 672 } 673 674 /* 675 * Create a new cluster at (cparent, lbase) and assign physical storage, 676 * returning a cluster suitable for I/O. The cluster will be in a modified 677 * state. Any chain->error will be rolled up into *errorp, but still 678 * returned. Caller must check *errorp. Caller need not check chain->error. 679 * 680 * cparent can wind up being anything. 681 * 682 * If datap is not NULL, *datap points to the real data we intend to write. 683 * If we can dedup the storage location we set *datap to NULL to indicate 684 * to the caller that a dedup occurred. 685 * 686 * NOTE: Special case for data embedded in inode. 687 */ 688 static 689 hammer2_chain_t * 690 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 691 hammer2_key_t lbase, int pblksize, 692 hammer2_tid_t mtid, char **datap, int *errorp) 693 { 694 hammer2_chain_t *chain; 695 hammer2_key_t key_dummy; 696 hammer2_off_t dedup_off; 697 int pradix = hammer2_getradix(pblksize); 698 699 /* 700 * Locate the chain associated with lbase, return a locked chain. 701 * However, do not instantiate any data reference (which utilizes a 702 * device buffer) because we will be using direct IO via the 703 * logical buffer cache buffer. 704 */ 705 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 706 retry: 707 chain = hammer2_chain_lookup(parentp, &key_dummy, 708 lbase, lbase, 709 errorp, 710 HAMMER2_LOOKUP_NODATA); 711 712 /* 713 * The lookup code should not return a DELETED chain to us, unless 714 * its a short-file embedded in the inode. Then it is possible for 715 * the lookup to return a deleted inode. 716 */ 717 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED) && 718 chain->bref.type != HAMMER2_BREF_TYPE_INODE) { 719 kprintf("assign physical deleted chain @ " 720 "%016jx (%016jx.%02x) ip %016jx\n", 721 lbase, chain->bref.data_off, chain->bref.type, 722 ip->meta.inum); 723 Debugger("bleh"); 724 } 725 726 if (chain == NULL) { 727 /* 728 * We found a hole, create a new chain entry. 729 * 730 * NOTE: DATA chains are created without device backing 731 * store (nor do we want any). 732 */ 733 dedup_off = hammer2_dedup_lookup((*parentp)->hmp, datap, 734 pblksize); 735 *errorp = hammer2_chain_create(parentp, &chain, 736 ip->pmp, 737 HAMMER2_ENC_CHECK(ip->meta.check_algo) | 738 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE), 739 lbase, HAMMER2_PBUFRADIX, 740 HAMMER2_BREF_TYPE_DATA, 741 pblksize, mtid, 742 dedup_off, 0); 743 if (chain == NULL) { 744 panic("hammer2_chain_create: par=%p error=%d\n", 745 *parentp, *errorp); 746 goto retry; 747 } 748 /*ip->delta_dcount += pblksize;*/ 749 } else if (chain->error == 0) { 750 switch (chain->bref.type) { 751 case HAMMER2_BREF_TYPE_INODE: 752 /* 753 * The data is embedded in the inode, which requires 754 * a bit more finess. 755 */ 756 hammer2_chain_modify_ip(ip, chain, mtid, 0); 757 break; 758 case HAMMER2_BREF_TYPE_DATA: 759 dedup_off = hammer2_dedup_lookup(chain->hmp, datap, 760 pblksize); 761 if (chain->bytes != pblksize) { 762 hammer2_chain_resize(chain, 763 mtid, dedup_off, 764 pradix, 765 HAMMER2_MODIFY_OPTDATA); 766 } 767 768 /* 769 * DATA buffers must be marked modified whether the 770 * data is in a logical buffer or not. We also have 771 * to make this call to fixup the chain data pointers 772 * after resizing in case this is an encrypted or 773 * compressed buffer. 774 */ 775 hammer2_chain_modify(chain, mtid, dedup_off, 776 HAMMER2_MODIFY_OPTDATA); 777 break; 778 default: 779 panic("hammer2_assign_physical: bad type"); 780 /* NOT REACHED */ 781 break; 782 } 783 } else { 784 *errorp = chain->error; 785 } 786 return (chain); 787 } 788 789 /* 790 * hammer2_write_file_core() - hammer2_write_thread() helper 791 * 792 * The core write function which determines which path to take 793 * depending on compression settings. We also have to locate the 794 * related chains so we can calculate and set the check data for 795 * the blockref. 796 */ 797 static 798 void 799 hammer2_write_file_core(char *data, hammer2_inode_t *ip, 800 hammer2_chain_t **parentp, 801 hammer2_key_t lbase, int ioflag, int pblksize, 802 hammer2_tid_t mtid, int *errorp) 803 { 804 hammer2_chain_t *chain; 805 char *bdata; 806 807 *errorp = 0; 808 809 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 810 case HAMMER2_COMP_NONE: 811 /* 812 * We have to assign physical storage to the buffer 813 * we intend to dirty or write now to avoid deadlocks 814 * in the strategy code later. 815 * 816 * This can return NOOFFSET for inode-embedded data. 817 * The strategy code will take care of it in that case. 818 */ 819 bdata = data; 820 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 821 mtid, &bdata, errorp); 822 if (*errorp) { 823 /* skip modifications */ 824 } else if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 825 hammer2_inode_data_t *wipdata; 826 827 wipdata = &chain->data->ipdata; 828 KKASSERT(wipdata->meta.op_flags & 829 HAMMER2_OPFLAG_DIRECTDATA); 830 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 831 ++hammer2_iod_file_wembed; 832 } else if (bdata == NULL) { 833 /* 834 * Copy of data already present on-media. 835 */ 836 chain->bref.methods = 837 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 838 HAMMER2_ENC_CHECK(ip->meta.check_algo); 839 hammer2_chain_setcheck(chain, data); 840 } else { 841 hammer2_write_bp(chain, data, ioflag, pblksize, 842 mtid, errorp, ip->meta.check_algo); 843 } 844 if (chain) { 845 hammer2_chain_unlock(chain); 846 hammer2_chain_drop(chain); 847 } 848 break; 849 case HAMMER2_COMP_AUTOZERO: 850 /* 851 * Check for zero-fill only 852 */ 853 hammer2_zero_check_and_write(data, ip, parentp, 854 lbase, ioflag, pblksize, 855 mtid, errorp, 856 ip->meta.check_algo); 857 break; 858 case HAMMER2_COMP_LZ4: 859 case HAMMER2_COMP_ZLIB: 860 default: 861 /* 862 * Check for zero-fill and attempt compression. 863 */ 864 hammer2_compress_and_write(data, ip, parentp, 865 lbase, ioflag, pblksize, 866 mtid, errorp, 867 ip->meta.comp_algo, 868 ip->meta.check_algo); 869 break; 870 } 871 } 872 873 /* 874 * Helper 875 * 876 * Generic function that will perform the compression in compression 877 * write path. The compression algorithm is determined by the settings 878 * obtained from inode. 879 */ 880 static 881 void 882 hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 883 hammer2_chain_t **parentp, 884 hammer2_key_t lbase, int ioflag, int pblksize, 885 hammer2_tid_t mtid, int *errorp, int comp_algo, int check_algo) 886 { 887 hammer2_chain_t *chain; 888 int comp_size; 889 int comp_block_size; 890 char *comp_buffer; 891 char *bdata; 892 893 /* 894 * An all-zeros write creates a hole unless the check code 895 * is disabled. When the check code is disabled all writes 896 * are done in-place, including any all-zeros writes. 897 * 898 * NOTE: A snapshot will still force a copy-on-write 899 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 900 */ 901 if (check_algo != HAMMER2_CHECK_NONE && 902 test_block_zeros(data, pblksize)) { 903 zero_write(data, ip, parentp, lbase, mtid, errorp); 904 return; 905 } 906 907 /* 908 * Compression requested. Try to compress the block. We store 909 * the data normally if we cannot sufficiently compress it. 910 * 911 * We have a heuristic to detect files which are mostly 912 * uncompressable and avoid the compression attempt in that 913 * case. If the compression heuristic is turned off, we always 914 * try to compress. 915 */ 916 comp_size = 0; 917 comp_buffer = NULL; 918 919 KKASSERT(pblksize / 2 <= 32768); 920 921 if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0 || 922 hammer2_always_compress) { 923 z_stream strm_compress; 924 int comp_level; 925 int ret; 926 927 switch(HAMMER2_DEC_ALGO(comp_algo)) { 928 case HAMMER2_COMP_LZ4: 929 comp_buffer = objcache_get(cache_buffer_write, 930 M_INTWAIT); 931 comp_size = LZ4_compress_limitedOutput( 932 data, 933 &comp_buffer[sizeof(int)], 934 pblksize, 935 pblksize / 2 - sizeof(int)); 936 /* 937 * We need to prefix with the size, LZ4 938 * doesn't do it for us. Add the related 939 * overhead. 940 */ 941 *(int *)comp_buffer = comp_size; 942 if (comp_size) 943 comp_size += sizeof(int); 944 break; 945 case HAMMER2_COMP_ZLIB: 946 comp_level = HAMMER2_DEC_LEVEL(comp_algo); 947 if (comp_level == 0) 948 comp_level = 6; /* default zlib compression */ 949 else if (comp_level < 6) 950 comp_level = 6; 951 else if (comp_level > 9) 952 comp_level = 9; 953 ret = deflateInit(&strm_compress, comp_level); 954 if (ret != Z_OK) { 955 kprintf("HAMMER2 ZLIB: fatal error " 956 "on deflateInit.\n"); 957 } 958 959 comp_buffer = objcache_get(cache_buffer_write, 960 M_INTWAIT); 961 strm_compress.next_in = data; 962 strm_compress.avail_in = pblksize; 963 strm_compress.next_out = comp_buffer; 964 strm_compress.avail_out = pblksize / 2; 965 ret = deflate(&strm_compress, Z_FINISH); 966 if (ret == Z_STREAM_END) { 967 comp_size = pblksize / 2 - 968 strm_compress.avail_out; 969 } else { 970 comp_size = 0; 971 } 972 ret = deflateEnd(&strm_compress); 973 break; 974 default: 975 kprintf("Error: Unknown compression method.\n"); 976 kprintf("Comp_method = %d.\n", comp_algo); 977 break; 978 } 979 } 980 981 if (comp_size == 0) { 982 /* 983 * compression failed or turned off 984 */ 985 comp_block_size = pblksize; /* safety */ 986 if (++ip->comp_heuristic > 128) 987 ip->comp_heuristic = 8; 988 } else { 989 /* 990 * compression succeeded 991 */ 992 ip->comp_heuristic = 0; 993 if (comp_size <= 1024) { 994 comp_block_size = 1024; 995 } else if (comp_size <= 2048) { 996 comp_block_size = 2048; 997 } else if (comp_size <= 4096) { 998 comp_block_size = 4096; 999 } else if (comp_size <= 8192) { 1000 comp_block_size = 8192; 1001 } else if (comp_size <= 16384) { 1002 comp_block_size = 16384; 1003 } else if (comp_size <= 32768) { 1004 comp_block_size = 32768; 1005 } else { 1006 panic("hammer2: WRITE PATH: " 1007 "Weird comp_size value."); 1008 /* NOT REACHED */ 1009 comp_block_size = pblksize; 1010 } 1011 1012 /* 1013 * Must zero the remainder or dedup (which operates on a 1014 * physical block basis) will not find matches. 1015 */ 1016 if (comp_size < comp_block_size) { 1017 bzero(comp_buffer + comp_size, 1018 comp_block_size - comp_size); 1019 } 1020 } 1021 1022 /* 1023 * Assign physical storage, data will be set to NULL if a live-dedup 1024 * was successful. 1025 */ 1026 bdata = comp_size ? comp_buffer : data; 1027 chain = hammer2_assign_physical(ip, parentp, lbase, comp_block_size, 1028 mtid, &bdata, errorp); 1029 1030 if (*errorp) { 1031 kprintf("WRITE PATH: An error occurred while " 1032 "assigning physical space.\n"); 1033 KKASSERT(chain == NULL); 1034 goto done; 1035 } 1036 1037 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1038 hammer2_inode_data_t *wipdata; 1039 1040 hammer2_chain_modify_ip(ip, chain, mtid, 0); 1041 wipdata = &chain->data->ipdata; 1042 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1043 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1044 ++hammer2_iod_file_wembed; 1045 } else if (bdata == NULL) { 1046 /* 1047 * Live deduplication, a copy of the data is already present 1048 * on the media. 1049 */ 1050 if (comp_size) { 1051 chain->bref.methods = 1052 HAMMER2_ENC_COMP(comp_algo) + 1053 HAMMER2_ENC_CHECK(check_algo); 1054 } else { 1055 chain->bref.methods = 1056 HAMMER2_ENC_COMP( 1057 HAMMER2_COMP_NONE) + 1058 HAMMER2_ENC_CHECK(check_algo); 1059 } 1060 bdata = comp_size ? comp_buffer : data; 1061 hammer2_chain_setcheck(chain, bdata); 1062 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1063 } else { 1064 hammer2_io_t *dio; 1065 1066 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1067 1068 switch(chain->bref.type) { 1069 case HAMMER2_BREF_TYPE_INODE: 1070 panic("hammer2_write_bp: unexpected inode\n"); 1071 break; 1072 case HAMMER2_BREF_TYPE_DATA: 1073 /* 1074 * Optimize out the read-before-write 1075 * if possible. 1076 */ 1077 *errorp = hammer2_io_newnz(chain->hmp, 1078 chain->bref.type, 1079 chain->bref.data_off, 1080 chain->bytes, 1081 &dio); 1082 if (*errorp) { 1083 hammer2_io_brelse(&dio); 1084 kprintf("hammer2: WRITE PATH: " 1085 "dbp bread error\n"); 1086 break; 1087 } 1088 bdata = hammer2_io_data(dio, chain->bref.data_off); 1089 1090 /* 1091 * When loading the block make sure we don't 1092 * leave garbage after the compressed data. 1093 */ 1094 if (comp_size) { 1095 chain->bref.methods = 1096 HAMMER2_ENC_COMP(comp_algo) + 1097 HAMMER2_ENC_CHECK(check_algo); 1098 bcopy(comp_buffer, bdata, comp_size); 1099 } else { 1100 chain->bref.methods = 1101 HAMMER2_ENC_COMP( 1102 HAMMER2_COMP_NONE) + 1103 HAMMER2_ENC_CHECK(check_algo); 1104 bcopy(data, bdata, pblksize); 1105 } 1106 1107 /* 1108 * The flush code doesn't calculate check codes for 1109 * file data (doing so can result in excessive I/O), 1110 * so we do it here. 1111 */ 1112 hammer2_chain_setcheck(chain, bdata); 1113 1114 /* 1115 * Device buffer is now valid, chain is no longer in 1116 * the initial state. 1117 * 1118 * (No blockref table worries with file data) 1119 */ 1120 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1121 hammer2_dedup_record(chain, dio, bdata); 1122 1123 /* Now write the related bdp. */ 1124 if (ioflag & IO_SYNC) { 1125 /* 1126 * Synchronous I/O requested. 1127 */ 1128 hammer2_io_bwrite(&dio); 1129 /* 1130 } else if ((ioflag & IO_DIRECT) && 1131 loff + n == pblksize) { 1132 hammer2_io_bdwrite(&dio); 1133 */ 1134 } else if (ioflag & IO_ASYNC) { 1135 hammer2_io_bawrite(&dio); 1136 } else { 1137 hammer2_io_bdwrite(&dio); 1138 } 1139 break; 1140 default: 1141 panic("hammer2_write_bp: bad chain type %d\n", 1142 chain->bref.type); 1143 /* NOT REACHED */ 1144 break; 1145 } 1146 } 1147 done: 1148 if (chain) { 1149 hammer2_chain_unlock(chain); 1150 hammer2_chain_drop(chain); 1151 } 1152 if (comp_buffer) 1153 objcache_put(cache_buffer_write, comp_buffer); 1154 } 1155 1156 /* 1157 * Helper 1158 * 1159 * Function that performs zero-checking and writing without compression, 1160 * it corresponds to default zero-checking path. 1161 */ 1162 static 1163 void 1164 hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 1165 hammer2_chain_t **parentp, 1166 hammer2_key_t lbase, int ioflag, int pblksize, 1167 hammer2_tid_t mtid, int *errorp, 1168 int check_algo) 1169 { 1170 hammer2_chain_t *chain; 1171 char *bdata; 1172 1173 if (check_algo != HAMMER2_CHECK_NONE && 1174 test_block_zeros(data, pblksize)) { 1175 /* 1176 * An all-zeros write creates a hole unless the check code 1177 * is disabled. When the check code is disabled all writes 1178 * are done in-place, including any all-zeros writes. 1179 * 1180 * NOTE: A snapshot will still force a copy-on-write 1181 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 1182 */ 1183 zero_write(data, ip, parentp, lbase, mtid, errorp); 1184 } else { 1185 /* 1186 * Normal write 1187 */ 1188 bdata = data; 1189 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 1190 mtid, &bdata, errorp); 1191 if (*errorp) { 1192 /* do nothing */ 1193 } else if (bdata) { 1194 hammer2_write_bp(chain, data, ioflag, pblksize, 1195 mtid, errorp, check_algo); 1196 } else { 1197 /* dedup occurred */ 1198 chain->bref.methods = 1199 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1200 HAMMER2_ENC_CHECK(check_algo); 1201 hammer2_chain_setcheck(chain, data); 1202 } 1203 if (chain) { 1204 hammer2_chain_unlock(chain); 1205 hammer2_chain_drop(chain); 1206 } 1207 } 1208 } 1209 1210 /* 1211 * Helper 1212 * 1213 * A function to test whether a block of data contains only zeros, 1214 * returns TRUE (non-zero) if the block is all zeros. 1215 */ 1216 static 1217 int 1218 test_block_zeros(const char *buf, size_t bytes) 1219 { 1220 size_t i; 1221 1222 for (i = 0; i < bytes; i += sizeof(long)) { 1223 if (*(const long *)(buf + i) != 0) 1224 return (0); 1225 } 1226 return (1); 1227 } 1228 1229 /* 1230 * Helper 1231 * 1232 * Function to "write" a block that contains only zeros. 1233 */ 1234 static 1235 void 1236 zero_write(char *data, hammer2_inode_t *ip, 1237 hammer2_chain_t **parentp, 1238 hammer2_key_t lbase, hammer2_tid_t mtid, int *errorp) 1239 { 1240 hammer2_chain_t *chain; 1241 hammer2_key_t key_dummy; 1242 1243 chain = hammer2_chain_lookup(parentp, &key_dummy, 1244 lbase, lbase, 1245 errorp, 1246 HAMMER2_LOOKUP_NODATA); 1247 if (chain) { 1248 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1249 hammer2_inode_data_t *wipdata; 1250 1251 hammer2_chain_modify_ip(ip, chain, mtid, 0); 1252 wipdata = &chain->data->ipdata; 1253 KKASSERT(wipdata->meta.op_flags & 1254 HAMMER2_OPFLAG_DIRECTDATA); 1255 bzero(wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1256 ++hammer2_iod_file_wembed; 1257 } else { 1258 hammer2_chain_delete(*parentp, chain, 1259 mtid, HAMMER2_DELETE_PERMANENT); 1260 ++hammer2_iod_file_wzero; 1261 } 1262 hammer2_chain_unlock(chain); 1263 hammer2_chain_drop(chain); 1264 } else { 1265 ++hammer2_iod_file_wzero; 1266 } 1267 } 1268 1269 /* 1270 * Helper 1271 * 1272 * Function to write the data as it is, without performing any sort of 1273 * compression. This function is used in path without compression and 1274 * default zero-checking path. 1275 */ 1276 static 1277 void 1278 hammer2_write_bp(hammer2_chain_t *chain, char *data, int ioflag, 1279 int pblksize, 1280 hammer2_tid_t mtid, int *errorp, int check_algo) 1281 { 1282 hammer2_inode_data_t *wipdata; 1283 hammer2_io_t *dio; 1284 char *bdata; 1285 int error; 1286 1287 error = 0; /* XXX TODO below */ 1288 1289 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1290 1291 switch(chain->bref.type) { 1292 case HAMMER2_BREF_TYPE_INODE: 1293 wipdata = &chain->data->ipdata; 1294 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1295 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1296 error = 0; 1297 ++hammer2_iod_file_wembed; 1298 break; 1299 case HAMMER2_BREF_TYPE_DATA: 1300 error = hammer2_io_newnz(chain->hmp, 1301 chain->bref.type, 1302 chain->bref.data_off, 1303 chain->bytes, &dio); 1304 if (error) { 1305 hammer2_io_bqrelse(&dio); 1306 kprintf("hammer2: WRITE PATH: " 1307 "dbp bread error\n"); 1308 break; 1309 } 1310 bdata = hammer2_io_data(dio, chain->bref.data_off); 1311 1312 chain->bref.methods = HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1313 HAMMER2_ENC_CHECK(check_algo); 1314 bcopy(data, bdata, chain->bytes); 1315 1316 /* 1317 * The flush code doesn't calculate check codes for 1318 * file data (doing so can result in excessive I/O), 1319 * so we do it here. 1320 */ 1321 hammer2_chain_setcheck(chain, bdata); 1322 1323 /* 1324 * Device buffer is now valid, chain is no longer in 1325 * the initial state. 1326 * 1327 * (No blockref table worries with file data) 1328 */ 1329 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1330 hammer2_dedup_record(chain, dio, bdata); 1331 1332 if (ioflag & IO_SYNC) { 1333 /* 1334 * Synchronous I/O requested. 1335 */ 1336 hammer2_io_bwrite(&dio); 1337 /* 1338 } else if ((ioflag & IO_DIRECT) && 1339 loff + n == pblksize) { 1340 hammer2_io_bdwrite(&dio); 1341 */ 1342 } else if (ioflag & IO_ASYNC) { 1343 hammer2_io_bawrite(&dio); 1344 } else { 1345 hammer2_io_bdwrite(&dio); 1346 } 1347 break; 1348 default: 1349 panic("hammer2_write_bp: bad chain type %d\n", 1350 chain->bref.type); 1351 /* NOT REACHED */ 1352 error = 0; 1353 break; 1354 } 1355 KKASSERT(error == 0); /* XXX TODO */ 1356 *errorp = error; 1357 } 1358 1359 /* 1360 * LIVE DEDUP HEURISTICS 1361 * 1362 * Record media and crc information for possible dedup operation. Note 1363 * that the dedup mask bits must also be set in the related DIO for a dedup 1364 * to be fully validated (which is handled in the freemap allocation code). 1365 * 1366 * WARNING! This code is SMP safe but the heuristic allows SMP collisions. 1367 * All fields must be loaded into locals and validated. 1368 * 1369 * WARNING! Should only be used for file data and directory entries, 1370 * hammer2_chain_modify() only checks for the dedup case on data 1371 * chains. Also, dedup data can only be recorded for committed 1372 * chains (so NOT strategy writes which can undergo further 1373 * modification after the fact!). 1374 */ 1375 void 1376 hammer2_dedup_record(hammer2_chain_t *chain, hammer2_io_t *dio, char *data) 1377 { 1378 hammer2_dev_t *hmp; 1379 hammer2_dedup_t *dedup; 1380 uint64_t crc; 1381 uint64_t mask; 1382 int best = 0; 1383 int i; 1384 int dticks; 1385 1386 /* 1387 * We can only record a dedup if we have media data to test against. 1388 * If dedup is not enabled, return early, which allows a chain to 1389 * remain marked MODIFIED (which might have benefits in special 1390 * situations, though typically it does not). 1391 */ 1392 if (hammer2_dedup_enable == 0) 1393 return; 1394 if (dio == NULL) { 1395 dio = chain->dio; 1396 if (dio == NULL) 1397 return; 1398 } 1399 1400 hmp = chain->hmp; 1401 1402 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 1403 case HAMMER2_CHECK_ISCSI32: 1404 /* 1405 * XXX use the built-in crc (the dedup lookup sequencing 1406 * needs to be fixed so the check code is already present 1407 * when dedup_lookup is called) 1408 */ 1409 #if 0 1410 crc = (uint64_t)(uint32_t)chain->bref.check.iscsi32.value; 1411 #endif 1412 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1413 break; 1414 case HAMMER2_CHECK_XXHASH64: 1415 crc = chain->bref.check.xxhash64.value; 1416 break; 1417 case HAMMER2_CHECK_SHA192: 1418 /* 1419 * XXX use the built-in crc (the dedup lookup sequencing 1420 * needs to be fixed so the check code is already present 1421 * when dedup_lookup is called) 1422 */ 1423 #if 0 1424 crc = ((uint64_t *)chain->bref.check.sha192.data)[0] ^ 1425 ((uint64_t *)chain->bref.check.sha192.data)[1] ^ 1426 ((uint64_t *)chain->bref.check.sha192.data)[2]; 1427 #endif 1428 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1429 break; 1430 default: 1431 /* 1432 * Cannot dedup without a check code 1433 * 1434 * NOTE: In particular, CHECK_NONE allows a sector to be 1435 * overwritten without copy-on-write, recording 1436 * a dedup block for a CHECK_NONE object would be 1437 * a disaster! 1438 */ 1439 return; 1440 } 1441 1442 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DEDUPABLE); 1443 1444 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1445 for (i = 0; i < 4; ++i) { 1446 if (dedup[i].data_crc == crc) { 1447 best = i; 1448 break; 1449 } 1450 dticks = (int)(dedup[i].ticks - dedup[best].ticks); 1451 if (dticks < 0 || dticks > hz * 60 * 30) 1452 best = i; 1453 } 1454 dedup += best; 1455 if (hammer2_debug & 0x40000) { 1456 kprintf("REC %04x %016jx %016jx\n", 1457 (int)(dedup - hmp->heur_dedup), 1458 crc, 1459 chain->bref.data_off); 1460 } 1461 dedup->ticks = ticks; 1462 dedup->data_off = chain->bref.data_off; 1463 dedup->data_crc = crc; 1464 1465 /* 1466 * Set the valid bits for the dedup only after we know the data 1467 * buffer has been updated. The alloc bits were set (and the valid 1468 * bits cleared) when the media was allocated. 1469 * 1470 * This is done in two stages becuase the bulkfree code can race 1471 * the gap between allocation and data population. Both masks must 1472 * be set before a bcmp/dedup operation is able to use the block. 1473 */ 1474 mask = hammer2_dedup_mask(dio, chain->bref.data_off, chain->bytes); 1475 atomic_set_64(&dio->dedup_valid, mask); 1476 1477 #if 0 1478 /* 1479 * XXX removed. MODIFIED is an integral part of the flush code, 1480 * lets not just clear it 1481 */ 1482 /* 1483 * Once we record the dedup the chain must be marked clean to 1484 * prevent reuse of the underlying block. Remember that this 1485 * write occurs when the buffer cache is flushed (i.e. on sync(), 1486 * fsync(), filesystem periodic sync, or when the kernel needs to 1487 * flush a buffer), and not whenever the user write()s. 1488 */ 1489 if (chain->flags & HAMMER2_CHAIN_MODIFIED) { 1490 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); 1491 atomic_add_long(&hammer2_count_modified_chains, -1); 1492 if (chain->pmp) 1493 hammer2_pfs_memory_wakeup(chain->pmp); 1494 } 1495 #endif 1496 } 1497 1498 static 1499 hammer2_off_t 1500 hammer2_dedup_lookup(hammer2_dev_t *hmp, char **datap, int pblksize) 1501 { 1502 hammer2_dedup_t *dedup; 1503 hammer2_io_t *dio; 1504 hammer2_off_t off; 1505 uint64_t crc; 1506 uint64_t mask; 1507 char *data; 1508 char *dtmp; 1509 int i; 1510 1511 if (hammer2_dedup_enable == 0) 1512 return 0; 1513 data = *datap; 1514 if (data == NULL) 1515 return 0; 1516 1517 /* 1518 * XXX use the built-in crc (the dedup lookup sequencing 1519 * needs to be fixed so the check code is already present 1520 * when dedup_lookup is called) 1521 */ 1522 crc = XXH64(data, pblksize, XXH_HAMMER2_SEED); 1523 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1524 1525 if (hammer2_debug & 0x40000) { 1526 kprintf("LOC %04x/4 %016jx\n", 1527 (int)(dedup - hmp->heur_dedup), 1528 crc); 1529 } 1530 1531 for (i = 0; i < 4; ++i) { 1532 off = dedup[i].data_off; 1533 cpu_ccfence(); 1534 if (dedup[i].data_crc != crc) 1535 continue; 1536 if ((1 << (int)(off & HAMMER2_OFF_MASK_RADIX)) != pblksize) 1537 continue; 1538 dio = hammer2_io_getquick(hmp, off, pblksize); 1539 if (dio) { 1540 dtmp = hammer2_io_data(dio, off), 1541 mask = hammer2_dedup_mask(dio, off, pblksize); 1542 if ((dio->dedup_alloc & mask) == mask && 1543 (dio->dedup_valid & mask) == mask && 1544 bcmp(data, dtmp, pblksize) == 0) { 1545 if (hammer2_debug & 0x40000) { 1546 kprintf("DEDUP SUCCESS %016jx\n", 1547 (intmax_t)off); 1548 } 1549 hammer2_io_putblk(&dio); 1550 *datap = NULL; 1551 dedup[i].ticks = ticks; /* update use */ 1552 atomic_add_long(&hammer2_iod_file_wdedup, 1553 pblksize); 1554 1555 return off; /* RETURN */ 1556 } 1557 hammer2_io_putblk(&dio); 1558 } 1559 } 1560 return 0; 1561 } 1562 1563 /* 1564 * Poof. Races are ok, if someone gets in and reuses a dedup offset 1565 * before or while we are clearing it they will also recover the freemap 1566 * entry (set it to fully allocated), so a bulkfree race can only set it 1567 * to a possibly-free state. 1568 * 1569 * XXX ok, well, not really sure races are ok but going to run with it 1570 * for the moment. 1571 */ 1572 void 1573 hammer2_dedup_clear(hammer2_dev_t *hmp) 1574 { 1575 int i; 1576 1577 for (i = 0; i < HAMMER2_DEDUP_HEUR_SIZE; ++i) { 1578 hmp->heur_dedup[i].data_off = 0; 1579 hmp->heur_dedup[i].ticks = ticks - 1; 1580 } 1581 } 1582