1 /* 2 * Copyright (c) 2011-2018 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/buf.h> 50 #include <sys/proc.h> 51 #include <sys/mount.h> 52 #include <sys/vnode.h> 53 #include <sys/objcache.h> 54 55 #include "hammer2.h" 56 #include "hammer2_lz4.h" 57 58 #include "zlib/hammer2_zlib.h" 59 60 struct objcache *cache_buffer_read; 61 struct objcache *cache_buffer_write; 62 63 /* 64 * Strategy code (async logical file buffer I/O from system) 65 * 66 * Except for the transaction init (which should normally not block), 67 * we essentially run the strategy operation asynchronously via a XOP. 68 * 69 * WARNING! The XOP deals with buffer synchronization. It is not synchronized 70 * to the current cpu. 71 * 72 * XXX This isn't supposed to be able to deadlock against vfs_sync vfsync() 73 * calls but it has in the past when multiple flushes are queued. 74 * 75 * XXX We currently terminate the transaction once we get a quorum, otherwise 76 * the frontend can stall, but this can leave the remaining nodes with 77 * a potential flush conflict. We need to delay flushes on those nodes 78 * until running transactions complete separately from the normal 79 * transaction sequencing. FIXME TODO. 80 */ 81 static int hammer2_strategy_read(struct vop_strategy_args *ap); 82 static int hammer2_strategy_write(struct vop_strategy_args *ap); 83 static void hammer2_strategy_read_completion(hammer2_chain_t *focus, 84 const char *data, struct bio *bio); 85 86 static hammer2_off_t hammer2_dedup_lookup(hammer2_dev_t *hmp, 87 char **datap, int pblksize); 88 89 int 90 hammer2_vop_strategy(struct vop_strategy_args *ap) 91 { 92 struct bio *biop; 93 struct buf *bp; 94 int error; 95 96 biop = ap->a_bio; 97 bp = biop->bio_buf; 98 99 switch(bp->b_cmd) { 100 case BUF_CMD_READ: 101 error = hammer2_strategy_read(ap); 102 break; 103 case BUF_CMD_WRITE: 104 error = hammer2_strategy_write(ap); 105 break; 106 default: 107 bp->b_error = error = EINVAL; 108 bp->b_flags |= B_ERROR; 109 biodone(biop); 110 break; 111 } 112 return (error); 113 } 114 115 /* 116 * Return the largest contiguous physical disk range for the logical 117 * request, in bytes. 118 * 119 * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb) 120 * 121 * Basically disabled, the logical buffer write thread has to deal with 122 * buffers one-at-a-time. Note that this should not prevent cluster_read() 123 * from reading-ahead, it simply prevents it from trying form a single 124 * cluster buffer for the logical request. H2 already uses 64KB buffers! 125 */ 126 int 127 hammer2_vop_bmap(struct vop_bmap_args *ap) 128 { 129 *ap->a_doffsetp = NOOFFSET; 130 if (ap->a_runp) 131 *ap->a_runp = 0; 132 if (ap->a_runb) 133 *ap->a_runb = 0; 134 return (EOPNOTSUPP); 135 } 136 137 /**************************************************************************** 138 * READ SUPPORT * 139 ****************************************************************************/ 140 /* 141 * Callback used in read path in case that a block is compressed with LZ4. 142 */ 143 static 144 void 145 hammer2_decompress_LZ4_callback(const char *data, u_int bytes, struct bio *bio) 146 { 147 struct buf *bp; 148 char *compressed_buffer; 149 int compressed_size; 150 int result; 151 152 bp = bio->bio_buf; 153 154 #if 0 155 if bio->bio_caller_info2.index && 156 bio->bio_caller_info1.uvalue32 != 157 crc32(bp->b_data, bp->b_bufsize) --- return error 158 #endif 159 160 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 161 compressed_size = *(const int *)data; 162 KKASSERT((uint32_t)compressed_size <= bytes - sizeof(int)); 163 164 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 165 result = LZ4_decompress_safe(__DECONST(char *, &data[sizeof(int)]), 166 compressed_buffer, 167 compressed_size, 168 bp->b_bufsize); 169 if (result < 0) { 170 kprintf("READ PATH: Error during decompression." 171 "bio %016jx/%d\n", 172 (intmax_t)bio->bio_offset, bytes); 173 /* make sure it isn't random garbage */ 174 bzero(compressed_buffer, bp->b_bufsize); 175 } 176 KKASSERT(result <= bp->b_bufsize); 177 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 178 if (result < bp->b_bufsize) 179 bzero(bp->b_data + result, bp->b_bufsize - result); 180 objcache_put(cache_buffer_read, compressed_buffer); 181 bp->b_resid = 0; 182 bp->b_flags |= B_AGE; 183 } 184 185 /* 186 * Callback used in read path in case that a block is compressed with ZLIB. 187 * It is almost identical to LZ4 callback, so in theory they can be unified, 188 * but we didn't want to make changes in bio structure for that. 189 */ 190 static 191 void 192 hammer2_decompress_ZLIB_callback(const char *data, u_int bytes, struct bio *bio) 193 { 194 struct buf *bp; 195 char *compressed_buffer; 196 z_stream strm_decompress; 197 int result; 198 int ret; 199 200 bp = bio->bio_buf; 201 202 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 203 strm_decompress.avail_in = 0; 204 strm_decompress.next_in = Z_NULL; 205 206 ret = inflateInit(&strm_decompress); 207 208 if (ret != Z_OK) 209 kprintf("HAMMER2 ZLIB: Fatal error in inflateInit.\n"); 210 211 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 212 strm_decompress.next_in = __DECONST(char *, data); 213 214 /* XXX supply proper size, subset of device bp */ 215 strm_decompress.avail_in = bytes; 216 strm_decompress.next_out = compressed_buffer; 217 strm_decompress.avail_out = bp->b_bufsize; 218 219 ret = inflate(&strm_decompress, Z_FINISH); 220 if (ret != Z_STREAM_END) { 221 kprintf("HAMMER2 ZLIB: Fatal error during decompression.\n"); 222 bzero(compressed_buffer, bp->b_bufsize); 223 } 224 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 225 result = bp->b_bufsize - strm_decompress.avail_out; 226 if (result < bp->b_bufsize) 227 bzero(bp->b_data + result, strm_decompress.avail_out); 228 objcache_put(cache_buffer_read, compressed_buffer); 229 ret = inflateEnd(&strm_decompress); 230 231 bp->b_resid = 0; 232 bp->b_flags |= B_AGE; 233 } 234 235 /* 236 * Logical buffer I/O, async read. 237 */ 238 static 239 int 240 hammer2_strategy_read(struct vop_strategy_args *ap) 241 { 242 hammer2_xop_strategy_t *xop; 243 struct bio *bio; 244 hammer2_inode_t *ip; 245 hammer2_key_t lbase; 246 247 bio = ap->a_bio; 248 ip = VTOI(ap->a_vp); 249 250 lbase = bio->bio_offset; 251 KKASSERT(((int)lbase & HAMMER2_PBUFMASK) == 0); 252 253 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_STRATEGY); 254 xop->finished = 0; 255 xop->bio = bio; 256 xop->lbase = lbase; 257 hammer2_mtx_init(&xop->lock, "h2bior"); 258 hammer2_xop_start(&xop->head, &hammer2_strategy_read_desc); 259 /* asynchronous completion */ 260 261 return(0); 262 } 263 264 /* 265 * Per-node XOP (threaded), do a synchronous lookup of the chain and 266 * its data. The frontend is asynchronous, so we are also responsible 267 * for racing to terminate the frontend. 268 */ 269 void 270 hammer2_xop_strategy_read(hammer2_xop_t *arg, void *scratch, int clindex) 271 { 272 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 273 hammer2_chain_t *parent; 274 hammer2_chain_t *chain; 275 hammer2_chain_t *focus; 276 hammer2_key_t key_dummy; 277 hammer2_key_t lbase; 278 struct bio *bio; 279 struct buf *bp; 280 const char *data; 281 int error; 282 283 /* 284 * Note that we can race completion of the bio supplied by 285 * the front-end so we cannot access it until we determine 286 * that we are the ones finishing it up. 287 */ 288 lbase = xop->lbase; 289 290 /* 291 * This is difficult to optimize. The logical buffer might be 292 * partially dirty (contain dummy zero-fill pages), which would 293 * mess up our crc calculation if we were to try a direct read. 294 * So for now we always double-buffer through the underlying 295 * storage. 296 * 297 * If not for the above problem we could conditionalize on 298 * (1) 64KB buffer, (2) one chain (not multi-master) and 299 * (3) !hammer2_double_buffer, and issue a direct read into the 300 * logical buffer. 301 */ 302 parent = hammer2_inode_chain(xop->head.ip1, clindex, 303 HAMMER2_RESOLVE_ALWAYS | 304 HAMMER2_RESOLVE_SHARED); 305 if (parent) { 306 chain = hammer2_chain_lookup(&parent, &key_dummy, 307 lbase, lbase, 308 &error, 309 HAMMER2_LOOKUP_ALWAYS | 310 HAMMER2_LOOKUP_SHARED); 311 if (chain) 312 error = chain->error; 313 } else { 314 error = HAMMER2_ERROR_EIO; 315 chain = NULL; 316 } 317 error = hammer2_xop_feed(&xop->head, chain, clindex, error); 318 if (chain) { 319 hammer2_chain_unlock(chain); 320 hammer2_chain_drop(chain); 321 } 322 if (parent) { 323 hammer2_chain_unlock(parent); 324 hammer2_chain_drop(parent); 325 } 326 chain = NULL; /* safety */ 327 parent = NULL; /* safety */ 328 329 /* 330 * Race to finish the frontend. First-to-complete. bio is only 331 * valid if we are determined to be the ones able to complete 332 * the operation. 333 */ 334 if (xop->finished) 335 return; 336 hammer2_mtx_ex(&xop->lock); 337 if (xop->finished) { 338 hammer2_mtx_unlock(&xop->lock); 339 return; 340 } 341 bio = xop->bio; 342 bp = bio->bio_buf; 343 bkvasync(bp); 344 345 /* 346 * Async operation has not completed and we now own the lock. 347 * Determine if we can complete the operation by issuing the 348 * frontend collection non-blocking. 349 * 350 * H2 double-buffers the data, setting B_NOTMETA on the logical 351 * buffer hints to the OS that the logical buffer should not be 352 * swapcached (since the device buffer can be). 353 * 354 * Also note that even for compressed data we would rather the 355 * kernel cache/swapcache device buffers more and (decompressed) 356 * logical buffers less, since that will significantly improve 357 * the amount of end-user data that can be cached. 358 * 359 * NOTE: The chain->data for xop->head.cluster.focus will be 360 * synchronized to the current cpu by xop_collect(), 361 * but other chains in the cluster might not be. 362 */ 363 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 364 365 switch(error) { 366 case 0: 367 xop->finished = 1; 368 hammer2_mtx_unlock(&xop->lock); 369 bp->b_flags |= B_NOTMETA; 370 focus = xop->head.cluster.focus; 371 data = hammer2_xop_gdata(&xop->head)->buf; 372 hammer2_strategy_read_completion(focus, data, xop->bio); 373 hammer2_xop_pdata(&xop->head); 374 biodone(bio); 375 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 376 break; 377 case HAMMER2_ERROR_ENOENT: 378 xop->finished = 1; 379 hammer2_mtx_unlock(&xop->lock); 380 bp->b_flags |= B_NOTMETA; 381 bp->b_resid = 0; 382 bp->b_error = 0; 383 bzero(bp->b_data, bp->b_bcount); 384 biodone(bio); 385 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 386 break; 387 case HAMMER2_ERROR_EINPROGRESS: 388 hammer2_mtx_unlock(&xop->lock); 389 break; 390 default: 391 kprintf("xop_strategy_read: error %08x loff=%016jx\n", 392 error, (intmax_t)bp->b_loffset); 393 xop->finished = 1; 394 hammer2_mtx_unlock(&xop->lock); 395 bp->b_flags |= B_ERROR; 396 bp->b_error = EIO; 397 biodone(bio); 398 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 399 break; 400 } 401 } 402 403 static 404 void 405 hammer2_strategy_read_completion(hammer2_chain_t *focus, const char *data, 406 struct bio *bio) 407 { 408 struct buf *bp = bio->bio_buf; 409 410 if (focus->bref.type == HAMMER2_BREF_TYPE_INODE) { 411 /* 412 * Copy from in-memory inode structure. 413 */ 414 bcopy(((const hammer2_inode_data_t *)data)->u.data, 415 bp->b_data, HAMMER2_EMBEDDED_BYTES); 416 bzero(bp->b_data + HAMMER2_EMBEDDED_BYTES, 417 bp->b_bcount - HAMMER2_EMBEDDED_BYTES); 418 bp->b_resid = 0; 419 bp->b_error = 0; 420 } else if (focus->bref.type == HAMMER2_BREF_TYPE_DATA) { 421 /* 422 * Data is on-media, record for live dedup. Release the 423 * chain (try to free it) when done. The data is still 424 * cached by both the buffer cache in front and the 425 * block device behind us. This leaves more room in the 426 * LRU chain cache for meta-data chains which we really 427 * want to retain. 428 * 429 * NOTE: Deduplication cannot be safely recorded for 430 * records without a check code. 431 */ 432 hammer2_dedup_record(focus, NULL, data); 433 atomic_set_int(&focus->flags, HAMMER2_CHAIN_RELEASE); 434 435 /* 436 * Decompression and copy. 437 */ 438 switch (HAMMER2_DEC_COMP(focus->bref.methods)) { 439 case HAMMER2_COMP_LZ4: 440 hammer2_decompress_LZ4_callback(data, focus->bytes, 441 bio); 442 /* b_resid set by call */ 443 break; 444 case HAMMER2_COMP_ZLIB: 445 hammer2_decompress_ZLIB_callback(data, focus->bytes, 446 bio); 447 /* b_resid set by call */ 448 break; 449 case HAMMER2_COMP_NONE: 450 KKASSERT(focus->bytes <= bp->b_bcount); 451 bcopy(data, bp->b_data, focus->bytes); 452 if (focus->bytes < bp->b_bcount) { 453 bzero(bp->b_data + focus->bytes, 454 bp->b_bcount - focus->bytes); 455 } 456 bp->b_resid = 0; 457 bp->b_error = 0; 458 break; 459 default: 460 panic("hammer2_strategy_read_completion: " 461 "unknown compression type"); 462 } 463 } else { 464 panic("hammer2_strategy_read_completion: unknown bref type"); 465 } 466 } 467 468 /**************************************************************************** 469 * WRITE SUPPORT * 470 ****************************************************************************/ 471 472 /* 473 * Functions for compression in threads, 474 * from hammer2_vnops.c 475 */ 476 static void hammer2_write_file_core(char *data, hammer2_inode_t *ip, 477 hammer2_chain_t **parentp, 478 hammer2_key_t lbase, int ioflag, int pblksize, 479 hammer2_tid_t mtid, int *errorp); 480 static void hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 481 hammer2_chain_t **parentp, 482 hammer2_key_t lbase, int ioflag, int pblksize, 483 hammer2_tid_t mtid, int *errorp, 484 int comp_algo, int check_algo); 485 static void hammer2_zero_check_and_write(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 int check_algo); 490 static int test_block_zeros(const char *buf, size_t bytes); 491 static void zero_write(char *data, hammer2_inode_t *ip, 492 hammer2_chain_t **parentp, 493 hammer2_key_t lbase, 494 hammer2_tid_t mtid, int *errorp); 495 static void hammer2_write_bp(hammer2_chain_t *chain, char *data, 496 int ioflag, int pblksize, 497 hammer2_tid_t mtid, int *errorp, 498 int check_algo); 499 500 int 501 hammer2_strategy_write(struct vop_strategy_args *ap) 502 { 503 hammer2_xop_strategy_t *xop; 504 hammer2_pfs_t *pmp; 505 struct bio *bio; 506 hammer2_inode_t *ip; 507 508 bio = ap->a_bio; 509 ip = VTOI(ap->a_vp); 510 pmp = ip->pmp; 511 512 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 513 hammer2_lwinprog_ref(pmp); 514 hammer2_trans_assert_strategy(pmp); 515 hammer2_trans_init(pmp, HAMMER2_TRANS_BUFCACHE); 516 517 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING | 518 HAMMER2_XOP_STRATEGY); 519 xop->finished = 0; 520 xop->bio = bio; 521 xop->lbase = bio->bio_offset; 522 hammer2_mtx_init(&xop->lock, "h2biow"); 523 hammer2_xop_start(&xop->head, &hammer2_strategy_write_desc); 524 /* asynchronous completion */ 525 526 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 527 528 return(0); 529 } 530 531 /* 532 * Per-node XOP (threaded). Write the logical buffer to the media. 533 * 534 * This is a bit problematic because there may be multiple target and 535 * any of them may be able to release the bp. In addition, if our 536 * particulr target is offline we don't want to block the bp (and thus 537 * the frontend). To accomplish this we copy the data to the per-thr 538 * scratch buffer. 539 */ 540 void 541 hammer2_xop_strategy_write(hammer2_xop_t *arg, void *scratch, int clindex) 542 { 543 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 544 hammer2_chain_t *parent; 545 hammer2_key_t lbase; 546 hammer2_inode_t *ip; 547 struct bio *bio; 548 struct buf *bp; 549 int error; 550 int lblksize; 551 int pblksize; 552 char *bio_data; 553 554 /* 555 * We can only access the bp/bio if the frontend has not yet 556 * completed. 557 */ 558 if (xop->finished) 559 return; 560 hammer2_mtx_sh(&xop->lock); 561 if (xop->finished) { 562 hammer2_mtx_unlock(&xop->lock); 563 return; 564 } 565 566 lbase = xop->lbase; 567 bio = xop->bio; /* ephermal */ 568 bp = bio->bio_buf; /* ephermal */ 569 ip = xop->head.ip1; /* retained by ref */ 570 bio_data = scratch; 571 572 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 573 574 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 575 pblksize = hammer2_calc_physical(ip, lbase); 576 bkvasync(bp); 577 KKASSERT(lblksize <= MAXPHYS); 578 bcopy(bp->b_data, bio_data, lblksize); 579 580 hammer2_mtx_unlock(&xop->lock); 581 bp = NULL; /* safety, illegal to access after unlock */ 582 bio = NULL; /* safety, illegal to access after unlock */ 583 584 /* 585 * Actual operation 586 */ 587 parent = hammer2_inode_chain(ip, clindex, HAMMER2_RESOLVE_ALWAYS); 588 hammer2_write_file_core(bio_data, ip, &parent, 589 lbase, IO_ASYNC, pblksize, 590 xop->head.mtid, &error); 591 if (parent) { 592 hammer2_chain_unlock(parent); 593 hammer2_chain_drop(parent); 594 parent = NULL; /* safety */ 595 } 596 hammer2_xop_feed(&xop->head, NULL, clindex, error); 597 598 /* 599 * Try to complete the operation on behalf of the front-end. 600 */ 601 if (xop->finished) 602 return; 603 hammer2_mtx_ex(&xop->lock); 604 if (xop->finished) { 605 hammer2_mtx_unlock(&xop->lock); 606 return; 607 } 608 609 /* 610 * Async operation has not completed and we now own the lock. 611 * Determine if we can complete the operation by issuing the 612 * frontend collection non-blocking. 613 * 614 * H2 double-buffers the data, setting B_NOTMETA on the logical 615 * buffer hints to the OS that the logical buffer should not be 616 * swapcached (since the device buffer can be). 617 */ 618 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 619 620 if (error == HAMMER2_ERROR_EINPROGRESS) { 621 hammer2_mtx_unlock(&xop->lock); 622 return; 623 } 624 625 /* 626 * Async operation has completed. 627 */ 628 xop->finished = 1; 629 hammer2_mtx_unlock(&xop->lock); 630 631 bio = xop->bio; /* now owned by us */ 632 bp = bio->bio_buf; /* now owned by us */ 633 634 if (error == HAMMER2_ERROR_ENOENT || error == 0) { 635 bp->b_flags |= B_NOTMETA; 636 bp->b_resid = 0; 637 bp->b_error = 0; 638 biodone(bio); 639 } else { 640 kprintf("xop_strategy_write: error %d loff=%016jx\n", 641 error, (intmax_t)bp->b_loffset); 642 bp->b_flags |= B_ERROR; 643 bp->b_error = EIO; 644 biodone(bio); 645 } 646 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 647 hammer2_trans_assert_strategy(ip->pmp); 648 hammer2_lwinprog_drop(ip->pmp); 649 hammer2_trans_done(ip->pmp, HAMMER2_TRANS_BUFCACHE); 650 } 651 652 /* 653 * Wait for pending I/O to complete 654 */ 655 void 656 hammer2_bioq_sync(hammer2_pfs_t *pmp) 657 { 658 hammer2_lwinprog_wait(pmp, 0); 659 } 660 661 /* 662 * Assign physical storage at (cparent, lbase), returning a suitable chain 663 * and setting *errorp appropriately. 664 * 665 * If no error occurs, the returned chain will be in a modified state. 666 * 667 * If an error occurs, the returned chain may or may not be NULL. If 668 * not-null any chain->error (if not 0) will also be rolled up into *errorp. 669 * So the caller only needs to test *errorp. 670 * 671 * cparent can wind up being anything. 672 * 673 * If datap is not NULL, *datap points to the real data we intend to write. 674 * If we can dedup the storage location we set *datap to NULL to indicate 675 * to the caller that a dedup occurred. 676 * 677 * NOTE: Special case for data embedded in inode. 678 */ 679 static 680 hammer2_chain_t * 681 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 682 hammer2_key_t lbase, int pblksize, 683 hammer2_tid_t mtid, char **datap, int *errorp) 684 { 685 hammer2_chain_t *chain; 686 hammer2_key_t key_dummy; 687 hammer2_off_t dedup_off; 688 int pradix = hammer2_getradix(pblksize); 689 690 /* 691 * Locate the chain associated with lbase, return a locked chain. 692 * However, do not instantiate any data reference (which utilizes a 693 * device buffer) because we will be using direct IO via the 694 * logical buffer cache buffer. 695 */ 696 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 697 698 chain = hammer2_chain_lookup(parentp, &key_dummy, 699 lbase, lbase, 700 errorp, 701 HAMMER2_LOOKUP_NODATA); 702 703 /* 704 * The lookup code should not return a DELETED chain to us, unless 705 * its a short-file embedded in the inode. Then it is possible for 706 * the lookup to return a deleted inode. 707 */ 708 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED) && 709 chain->bref.type != HAMMER2_BREF_TYPE_INODE) { 710 kprintf("assign physical deleted chain @ " 711 "%016jx (%016jx.%02x) ip %016jx\n", 712 lbase, chain->bref.data_off, chain->bref.type, 713 ip->meta.inum); 714 Debugger("bleh"); 715 } 716 717 if (chain == NULL) { 718 /* 719 * We found a hole, create a new chain entry. 720 * 721 * NOTE: DATA chains are created without device backing 722 * store (nor do we want any). 723 */ 724 dedup_off = hammer2_dedup_lookup((*parentp)->hmp, datap, 725 pblksize); 726 *errorp |= hammer2_chain_create(parentp, &chain, NULL, ip->pmp, 727 HAMMER2_ENC_CHECK(ip->meta.check_algo) | 728 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE), 729 lbase, HAMMER2_PBUFRADIX, 730 HAMMER2_BREF_TYPE_DATA, 731 pblksize, mtid, 732 dedup_off, 0); 733 if (chain == NULL) 734 goto failed; 735 /*ip->delta_dcount += pblksize;*/ 736 } else if (chain->error == 0) { 737 switch (chain->bref.type) { 738 case HAMMER2_BREF_TYPE_INODE: 739 /* 740 * The data is embedded in the inode, which requires 741 * a bit more finess. 742 */ 743 *errorp |= hammer2_chain_modify_ip(ip, chain, mtid, 0); 744 break; 745 case HAMMER2_BREF_TYPE_DATA: 746 dedup_off = hammer2_dedup_lookup(chain->hmp, datap, 747 pblksize); 748 if (chain->bytes != pblksize) { 749 *errorp |= hammer2_chain_resize(chain, 750 mtid, dedup_off, 751 pradix, 752 HAMMER2_MODIFY_OPTDATA); 753 if (*errorp) 754 break; 755 } 756 757 /* 758 * DATA buffers must be marked modified whether the 759 * data is in a logical buffer or not. We also have 760 * to make this call to fixup the chain data pointers 761 * after resizing in case this is an encrypted or 762 * compressed buffer. 763 */ 764 *errorp |= hammer2_chain_modify(chain, mtid, dedup_off, 765 HAMMER2_MODIFY_OPTDATA); 766 break; 767 default: 768 panic("hammer2_assign_physical: bad type"); 769 /* NOT REACHED */ 770 break; 771 } 772 } else { 773 *errorp = chain->error; 774 } 775 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 776 failed: 777 return (chain); 778 } 779 780 /* 781 * hammer2_write_file_core() 782 * 783 * The core write function which determines which path to take 784 * depending on compression settings. We also have to locate the 785 * related chains so we can calculate and set the check data for 786 * the blockref. 787 */ 788 static 789 void 790 hammer2_write_file_core(char *data, hammer2_inode_t *ip, 791 hammer2_chain_t **parentp, 792 hammer2_key_t lbase, int ioflag, int pblksize, 793 hammer2_tid_t mtid, int *errorp) 794 { 795 hammer2_chain_t *chain; 796 char *bdata; 797 798 *errorp = 0; 799 800 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 801 case HAMMER2_COMP_NONE: 802 /* 803 * We have to assign physical storage to the buffer 804 * we intend to dirty or write now to avoid deadlocks 805 * in the strategy code later. 806 * 807 * This can return NOOFFSET for inode-embedded data. 808 * The strategy code will take care of it in that case. 809 */ 810 bdata = data; 811 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 812 mtid, &bdata, errorp); 813 if (*errorp) { 814 /* skip modifications */ 815 } else if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 816 hammer2_inode_data_t *wipdata; 817 818 wipdata = &chain->data->ipdata; 819 KKASSERT(wipdata->meta.op_flags & 820 HAMMER2_OPFLAG_DIRECTDATA); 821 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 822 ++hammer2_iod_file_wembed; 823 } else if (bdata == NULL) { 824 /* 825 * Copy of data already present on-media. 826 */ 827 chain->bref.methods = 828 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 829 HAMMER2_ENC_CHECK(ip->meta.check_algo); 830 hammer2_chain_setcheck(chain, data); 831 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 832 } else { 833 hammer2_write_bp(chain, data, ioflag, pblksize, 834 mtid, errorp, ip->meta.check_algo); 835 } 836 if (chain) { 837 hammer2_chain_unlock(chain); 838 hammer2_chain_drop(chain); 839 } 840 break; 841 case HAMMER2_COMP_AUTOZERO: 842 /* 843 * Check for zero-fill only 844 */ 845 hammer2_zero_check_and_write(data, ip, parentp, 846 lbase, ioflag, pblksize, 847 mtid, errorp, 848 ip->meta.check_algo); 849 break; 850 case HAMMER2_COMP_LZ4: 851 case HAMMER2_COMP_ZLIB: 852 default: 853 /* 854 * Check for zero-fill and attempt compression. 855 */ 856 hammer2_compress_and_write(data, ip, parentp, 857 lbase, ioflag, pblksize, 858 mtid, errorp, 859 ip->meta.comp_algo, 860 ip->meta.check_algo); 861 break; 862 } 863 } 864 865 /* 866 * Helper 867 * 868 * Generic function that will perform the compression in compression 869 * write path. The compression algorithm is determined by the settings 870 * obtained from inode. 871 */ 872 static 873 void 874 hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 875 hammer2_chain_t **parentp, 876 hammer2_key_t lbase, int ioflag, int pblksize, 877 hammer2_tid_t mtid, int *errorp, int comp_algo, int check_algo) 878 { 879 hammer2_chain_t *chain; 880 int comp_size; 881 int comp_block_size; 882 char *comp_buffer; 883 char *bdata; 884 885 /* 886 * An all-zeros write creates a hole unless the check code 887 * is disabled. When the check code is disabled all writes 888 * are done in-place, including any all-zeros writes. 889 * 890 * NOTE: A snapshot will still force a copy-on-write 891 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 892 */ 893 if (check_algo != HAMMER2_CHECK_NONE && 894 test_block_zeros(data, pblksize)) { 895 zero_write(data, ip, parentp, lbase, mtid, errorp); 896 return; 897 } 898 899 /* 900 * Compression requested. Try to compress the block. We store 901 * the data normally if we cannot sufficiently compress it. 902 * 903 * We have a heuristic to detect files which are mostly 904 * uncompressable and avoid the compression attempt in that 905 * case. If the compression heuristic is turned off, we always 906 * try to compress. 907 */ 908 comp_size = 0; 909 comp_buffer = NULL; 910 911 KKASSERT(pblksize / 2 <= 32768); 912 913 if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0 || 914 hammer2_always_compress) { 915 z_stream strm_compress; 916 int comp_level; 917 int ret; 918 919 switch(HAMMER2_DEC_ALGO(comp_algo)) { 920 case HAMMER2_COMP_LZ4: 921 /* 922 * We need to prefix with the size, LZ4 923 * doesn't do it for us. Add the related 924 * overhead. 925 * 926 * NOTE: The LZ4 code seems to assume at least an 927 * 8-byte buffer size granularity and may 928 * overrun the buffer if given a 4-byte 929 * granularity. 930 */ 931 comp_buffer = objcache_get(cache_buffer_write, 932 M_INTWAIT); 933 comp_size = LZ4_compress_limitedOutput( 934 data, 935 &comp_buffer[sizeof(int)], 936 pblksize, 937 pblksize / 2 - sizeof(int64_t)); 938 *(int *)comp_buffer = comp_size; 939 if (comp_size) 940 comp_size += sizeof(int); 941 break; 942 case HAMMER2_COMP_ZLIB: 943 comp_level = HAMMER2_DEC_LEVEL(comp_algo); 944 if (comp_level == 0) 945 comp_level = 6; /* default zlib compression */ 946 else if (comp_level < 6) 947 comp_level = 6; 948 else if (comp_level > 9) 949 comp_level = 9; 950 ret = deflateInit(&strm_compress, comp_level); 951 if (ret != Z_OK) { 952 kprintf("HAMMER2 ZLIB: fatal error " 953 "on deflateInit.\n"); 954 } 955 956 comp_buffer = objcache_get(cache_buffer_write, 957 M_INTWAIT); 958 strm_compress.next_in = data; 959 strm_compress.avail_in = pblksize; 960 strm_compress.next_out = comp_buffer; 961 strm_compress.avail_out = pblksize / 2; 962 ret = deflate(&strm_compress, Z_FINISH); 963 if (ret == Z_STREAM_END) { 964 comp_size = pblksize / 2 - 965 strm_compress.avail_out; 966 } else { 967 comp_size = 0; 968 } 969 ret = deflateEnd(&strm_compress); 970 break; 971 default: 972 kprintf("Error: Unknown compression method.\n"); 973 kprintf("Comp_method = %d.\n", comp_algo); 974 break; 975 } 976 } 977 978 if (comp_size == 0) { 979 /* 980 * compression failed or turned off 981 */ 982 comp_block_size = pblksize; /* safety */ 983 if (++ip->comp_heuristic > 128) 984 ip->comp_heuristic = 8; 985 } else { 986 /* 987 * compression succeeded 988 */ 989 ip->comp_heuristic = 0; 990 if (comp_size <= 1024) { 991 comp_block_size = 1024; 992 } else if (comp_size <= 2048) { 993 comp_block_size = 2048; 994 } else if (comp_size <= 4096) { 995 comp_block_size = 4096; 996 } else if (comp_size <= 8192) { 997 comp_block_size = 8192; 998 } else if (comp_size <= 16384) { 999 comp_block_size = 16384; 1000 } else if (comp_size <= 32768) { 1001 comp_block_size = 32768; 1002 } else { 1003 panic("hammer2: WRITE PATH: " 1004 "Weird comp_size value."); 1005 /* NOT REACHED */ 1006 comp_block_size = pblksize; 1007 } 1008 1009 /* 1010 * Must zero the remainder or dedup (which operates on a 1011 * physical block basis) will not find matches. 1012 */ 1013 if (comp_size < comp_block_size) { 1014 bzero(comp_buffer + comp_size, 1015 comp_block_size - comp_size); 1016 } 1017 } 1018 1019 /* 1020 * Assign physical storage, bdata will be set to NULL if a live-dedup 1021 * was successful. 1022 */ 1023 bdata = comp_size ? comp_buffer : data; 1024 chain = hammer2_assign_physical(ip, parentp, lbase, comp_block_size, 1025 mtid, &bdata, errorp); 1026 1027 if (*errorp) { 1028 goto done; 1029 } 1030 1031 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1032 hammer2_inode_data_t *wipdata; 1033 1034 *errorp = hammer2_chain_modify_ip(ip, chain, mtid, 0); 1035 if (*errorp == 0) { 1036 wipdata = &chain->data->ipdata; 1037 KKASSERT(wipdata->meta.op_flags & 1038 HAMMER2_OPFLAG_DIRECTDATA); 1039 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1040 ++hammer2_iod_file_wembed; 1041 } 1042 } else if (bdata == NULL) { 1043 /* 1044 * Live deduplication, a copy of the data is already present 1045 * on the media. 1046 */ 1047 if (comp_size) { 1048 chain->bref.methods = 1049 HAMMER2_ENC_COMP(comp_algo) + 1050 HAMMER2_ENC_CHECK(check_algo); 1051 } else { 1052 chain->bref.methods = 1053 HAMMER2_ENC_COMP( 1054 HAMMER2_COMP_NONE) + 1055 HAMMER2_ENC_CHECK(check_algo); 1056 } 1057 bdata = comp_size ? comp_buffer : data; 1058 hammer2_chain_setcheck(chain, bdata); 1059 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1060 } else { 1061 hammer2_io_t *dio; 1062 1063 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1064 1065 switch(chain->bref.type) { 1066 case HAMMER2_BREF_TYPE_INODE: 1067 panic("hammer2_compress_and_write: unexpected inode\n"); 1068 break; 1069 case HAMMER2_BREF_TYPE_DATA: 1070 /* 1071 * Optimize out the read-before-write 1072 * if possible. 1073 */ 1074 *errorp = hammer2_io_newnz(chain->hmp, 1075 chain->bref.type, 1076 chain->bref.data_off, 1077 chain->bytes, 1078 &dio); 1079 if (*errorp) { 1080 hammer2_io_brelse(&dio); 1081 kprintf("hammer2: WRITE PATH: " 1082 "dbp bread error\n"); 1083 break; 1084 } 1085 bdata = hammer2_io_data(dio, chain->bref.data_off); 1086 1087 /* 1088 * When loading the block make sure we don't 1089 * leave garbage after the compressed data. 1090 */ 1091 if (comp_size) { 1092 chain->bref.methods = 1093 HAMMER2_ENC_COMP(comp_algo) + 1094 HAMMER2_ENC_CHECK(check_algo); 1095 bcopy(comp_buffer, bdata, comp_block_size); 1096 } else { 1097 chain->bref.methods = 1098 HAMMER2_ENC_COMP( 1099 HAMMER2_COMP_NONE) + 1100 HAMMER2_ENC_CHECK(check_algo); 1101 bcopy(data, bdata, pblksize); 1102 } 1103 1104 /* 1105 * The flush code doesn't calculate check codes for 1106 * file data (doing so can result in excessive I/O), 1107 * so we do it here. 1108 */ 1109 hammer2_chain_setcheck(chain, bdata); 1110 1111 /* 1112 * Device buffer is now valid, chain is no longer in 1113 * the initial state. 1114 * 1115 * (No blockref table worries with file data) 1116 */ 1117 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1118 hammer2_dedup_record(chain, dio, bdata); 1119 1120 /* Now write the related bdp. */ 1121 if (ioflag & IO_SYNC) { 1122 /* 1123 * Synchronous I/O requested. 1124 */ 1125 hammer2_io_bwrite(&dio); 1126 /* 1127 } else if ((ioflag & IO_DIRECT) && 1128 loff + n == pblksize) { 1129 hammer2_io_bdwrite(&dio); 1130 */ 1131 } else if (ioflag & IO_ASYNC) { 1132 hammer2_io_bawrite(&dio); 1133 } else { 1134 hammer2_io_bdwrite(&dio); 1135 } 1136 break; 1137 default: 1138 panic("hammer2_compress_and_write: bad chain type %d\n", 1139 chain->bref.type); 1140 /* NOT REACHED */ 1141 break; 1142 } 1143 } 1144 done: 1145 if (chain) { 1146 hammer2_chain_unlock(chain); 1147 hammer2_chain_drop(chain); 1148 } 1149 if (comp_buffer) 1150 objcache_put(cache_buffer_write, comp_buffer); 1151 } 1152 1153 /* 1154 * Helper 1155 * 1156 * Function that performs zero-checking and writing without compression, 1157 * it corresponds to default zero-checking path. 1158 */ 1159 static 1160 void 1161 hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 1162 hammer2_chain_t **parentp, 1163 hammer2_key_t lbase, int ioflag, int pblksize, 1164 hammer2_tid_t mtid, int *errorp, 1165 int check_algo) 1166 { 1167 hammer2_chain_t *chain; 1168 char *bdata; 1169 1170 if (check_algo != HAMMER2_CHECK_NONE && 1171 test_block_zeros(data, pblksize)) { 1172 /* 1173 * An all-zeros write creates a hole unless the check code 1174 * is disabled. When the check code is disabled all writes 1175 * are done in-place, including any all-zeros writes. 1176 * 1177 * NOTE: A snapshot will still force a copy-on-write 1178 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 1179 */ 1180 zero_write(data, ip, parentp, lbase, mtid, errorp); 1181 } else { 1182 /* 1183 * Normal write (bdata set to NULL if de-duplicated) 1184 */ 1185 bdata = data; 1186 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 1187 mtid, &bdata, errorp); 1188 if (*errorp) { 1189 /* do nothing */ 1190 } else if (bdata) { 1191 hammer2_write_bp(chain, data, ioflag, pblksize, 1192 mtid, errorp, check_algo); 1193 } else { 1194 /* dedup occurred */ 1195 chain->bref.methods = 1196 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1197 HAMMER2_ENC_CHECK(check_algo); 1198 hammer2_chain_setcheck(chain, data); 1199 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1200 } 1201 if (chain) { 1202 hammer2_chain_unlock(chain); 1203 hammer2_chain_drop(chain); 1204 } 1205 } 1206 } 1207 1208 /* 1209 * Helper 1210 * 1211 * A function to test whether a block of data contains only zeros, 1212 * returns TRUE (non-zero) if the block is all zeros. 1213 */ 1214 static 1215 int 1216 test_block_zeros(const char *buf, size_t bytes) 1217 { 1218 size_t i; 1219 1220 for (i = 0; i < bytes; i += sizeof(long)) { 1221 if (*(const long *)(buf + i) != 0) 1222 return (0); 1223 } 1224 return (1); 1225 } 1226 1227 /* 1228 * Helper 1229 * 1230 * Function to "write" a block that contains only zeros. 1231 */ 1232 static 1233 void 1234 zero_write(char *data, hammer2_inode_t *ip, 1235 hammer2_chain_t **parentp, 1236 hammer2_key_t lbase, hammer2_tid_t mtid, int *errorp) 1237 { 1238 hammer2_chain_t *chain; 1239 hammer2_key_t key_dummy; 1240 1241 chain = hammer2_chain_lookup(parentp, &key_dummy, 1242 lbase, lbase, 1243 errorp, 1244 HAMMER2_LOOKUP_NODATA); 1245 if (chain) { 1246 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1247 hammer2_inode_data_t *wipdata; 1248 1249 if (*errorp == 0) { 1250 *errorp = hammer2_chain_modify_ip(ip, chain, 1251 mtid, 0); 1252 } 1253 if (*errorp == 0) { 1254 wipdata = &chain->data->ipdata; 1255 KKASSERT(wipdata->meta.op_flags & 1256 HAMMER2_OPFLAG_DIRECTDATA); 1257 bzero(wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1258 ++hammer2_iod_file_wembed; 1259 } 1260 } else { 1261 /* chain->error ok for deletion */ 1262 hammer2_chain_delete(*parentp, chain, 1263 mtid, HAMMER2_DELETE_PERMANENT); 1264 ++hammer2_iod_file_wzero; 1265 } 1266 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 1267 hammer2_chain_unlock(chain); 1268 hammer2_chain_drop(chain); 1269 } else { 1270 ++hammer2_iod_file_wzero; 1271 } 1272 } 1273 1274 /* 1275 * Helper 1276 * 1277 * Function to write the data as it is, without performing any sort of 1278 * compression. This function is used in path without compression and 1279 * default zero-checking path. 1280 */ 1281 static 1282 void 1283 hammer2_write_bp(hammer2_chain_t *chain, char *data, int ioflag, 1284 int pblksize, 1285 hammer2_tid_t mtid, int *errorp, int check_algo) 1286 { 1287 hammer2_inode_data_t *wipdata; 1288 hammer2_io_t *dio; 1289 char *bdata; 1290 int error; 1291 1292 error = 0; /* XXX TODO below */ 1293 1294 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1295 1296 switch(chain->bref.type) { 1297 case HAMMER2_BREF_TYPE_INODE: 1298 wipdata = &chain->data->ipdata; 1299 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1300 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1301 error = 0; 1302 ++hammer2_iod_file_wembed; 1303 break; 1304 case HAMMER2_BREF_TYPE_DATA: 1305 error = hammer2_io_newnz(chain->hmp, 1306 chain->bref.type, 1307 chain->bref.data_off, 1308 chain->bytes, &dio); 1309 if (error) { 1310 hammer2_io_bqrelse(&dio); 1311 kprintf("hammer2: WRITE PATH: " 1312 "dbp bread error\n"); 1313 break; 1314 } 1315 bdata = hammer2_io_data(dio, chain->bref.data_off); 1316 1317 chain->bref.methods = HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1318 HAMMER2_ENC_CHECK(check_algo); 1319 bcopy(data, bdata, chain->bytes); 1320 1321 /* 1322 * The flush code doesn't calculate check codes for 1323 * file data (doing so can result in excessive I/O), 1324 * so we do it here. 1325 */ 1326 hammer2_chain_setcheck(chain, bdata); 1327 1328 /* 1329 * Device buffer is now valid, chain is no longer in 1330 * the initial state. 1331 * 1332 * (No blockref table worries with file data) 1333 */ 1334 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1335 hammer2_dedup_record(chain, dio, bdata); 1336 1337 if (ioflag & IO_SYNC) { 1338 /* 1339 * Synchronous I/O requested. 1340 */ 1341 hammer2_io_bwrite(&dio); 1342 /* 1343 } else if ((ioflag & IO_DIRECT) && 1344 loff + n == pblksize) { 1345 hammer2_io_bdwrite(&dio); 1346 */ 1347 } else if (ioflag & IO_ASYNC) { 1348 hammer2_io_bawrite(&dio); 1349 } else { 1350 hammer2_io_bdwrite(&dio); 1351 } 1352 break; 1353 default: 1354 panic("hammer2_write_bp: bad chain type %d\n", 1355 chain->bref.type); 1356 /* NOT REACHED */ 1357 error = 0; 1358 break; 1359 } 1360 *errorp = error; 1361 } 1362 1363 /* 1364 * LIVE DEDUP HEURISTICS 1365 * 1366 * Record media and crc information for possible dedup operation. Note 1367 * that the dedup mask bits must also be set in the related DIO for a dedup 1368 * to be fully validated (which is handled in the freemap allocation code). 1369 * 1370 * WARNING! This code is SMP safe but the heuristic allows SMP collisions. 1371 * All fields must be loaded into locals and validated. 1372 * 1373 * WARNING! Should only be used for file data and directory entries, 1374 * hammer2_chain_modify() only checks for the dedup case on data 1375 * chains. Also, dedup data can only be recorded for committed 1376 * chains (so NOT strategy writes which can undergo further 1377 * modification after the fact!). 1378 */ 1379 void 1380 hammer2_dedup_record(hammer2_chain_t *chain, hammer2_io_t *dio, 1381 const char *data) 1382 { 1383 hammer2_dev_t *hmp; 1384 hammer2_dedup_t *dedup; 1385 uint64_t crc; 1386 uint64_t mask; 1387 int best = 0; 1388 int i; 1389 int dticks; 1390 1391 /* 1392 * We can only record a dedup if we have media data to test against. 1393 * If dedup is not enabled, return early, which allows a chain to 1394 * remain marked MODIFIED (which might have benefits in special 1395 * situations, though typically it does not). 1396 */ 1397 if (hammer2_dedup_enable == 0) 1398 return; 1399 if (dio == NULL) { 1400 dio = chain->dio; 1401 if (dio == NULL) 1402 return; 1403 } 1404 1405 hmp = chain->hmp; 1406 1407 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 1408 case HAMMER2_CHECK_ISCSI32: 1409 /* 1410 * XXX use the built-in crc (the dedup lookup sequencing 1411 * needs to be fixed so the check code is already present 1412 * when dedup_lookup is called) 1413 */ 1414 #if 0 1415 crc = (uint64_t)(uint32_t)chain->bref.check.iscsi32.value; 1416 #endif 1417 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1418 break; 1419 case HAMMER2_CHECK_XXHASH64: 1420 crc = chain->bref.check.xxhash64.value; 1421 break; 1422 case HAMMER2_CHECK_SHA192: 1423 /* 1424 * XXX use the built-in crc (the dedup lookup sequencing 1425 * needs to be fixed so the check code is already present 1426 * when dedup_lookup is called) 1427 */ 1428 #if 0 1429 crc = ((uint64_t *)chain->bref.check.sha192.data)[0] ^ 1430 ((uint64_t *)chain->bref.check.sha192.data)[1] ^ 1431 ((uint64_t *)chain->bref.check.sha192.data)[2]; 1432 #endif 1433 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1434 break; 1435 default: 1436 /* 1437 * Cannot dedup without a check code 1438 * 1439 * NOTE: In particular, CHECK_NONE allows a sector to be 1440 * overwritten without copy-on-write, recording 1441 * a dedup block for a CHECK_NONE object would be 1442 * a disaster! 1443 */ 1444 return; 1445 } 1446 1447 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DEDUPABLE); 1448 1449 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1450 for (i = 0; i < 4; ++i) { 1451 if (dedup[i].data_crc == crc) { 1452 best = i; 1453 break; 1454 } 1455 dticks = (int)(dedup[i].ticks - dedup[best].ticks); 1456 if (dticks < 0 || dticks > hz * 60 * 30) 1457 best = i; 1458 } 1459 dedup += best; 1460 if (hammer2_debug & 0x40000) { 1461 kprintf("REC %04x %016jx %016jx\n", 1462 (int)(dedup - hmp->heur_dedup), 1463 crc, 1464 chain->bref.data_off); 1465 } 1466 dedup->ticks = ticks; 1467 dedup->data_off = chain->bref.data_off; 1468 dedup->data_crc = crc; 1469 1470 /* 1471 * Set the valid bits for the dedup only after we know the data 1472 * buffer has been updated. The alloc bits were set (and the valid 1473 * bits cleared) when the media was allocated. 1474 * 1475 * This is done in two stages becuase the bulkfree code can race 1476 * the gap between allocation and data population. Both masks must 1477 * be set before a bcmp/dedup operation is able to use the block. 1478 */ 1479 mask = hammer2_dedup_mask(dio, chain->bref.data_off, chain->bytes); 1480 atomic_set_64(&dio->dedup_valid, mask); 1481 1482 #if 0 1483 /* 1484 * XXX removed. MODIFIED is an integral part of the flush code, 1485 * lets not just clear it 1486 */ 1487 /* 1488 * Once we record the dedup the chain must be marked clean to 1489 * prevent reuse of the underlying block. Remember that this 1490 * write occurs when the buffer cache is flushed (i.e. on sync(), 1491 * fsync(), filesystem periodic sync, or when the kernel needs to 1492 * flush a buffer), and not whenever the user write()s. 1493 */ 1494 if (chain->flags & HAMMER2_CHAIN_MODIFIED) { 1495 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); 1496 atomic_add_long(&hammer2_count_modified_chains, -1); 1497 if (chain->pmp) 1498 hammer2_pfs_memory_wakeup(chain->pmp, -1); 1499 } 1500 #endif 1501 } 1502 1503 static 1504 hammer2_off_t 1505 hammer2_dedup_lookup(hammer2_dev_t *hmp, char **datap, int pblksize) 1506 { 1507 hammer2_dedup_t *dedup; 1508 hammer2_io_t *dio; 1509 hammer2_off_t off; 1510 uint64_t crc; 1511 uint64_t mask; 1512 char *data; 1513 char *dtmp; 1514 int i; 1515 1516 if (hammer2_dedup_enable == 0) 1517 return 0; 1518 data = *datap; 1519 if (data == NULL) 1520 return 0; 1521 1522 /* 1523 * XXX use the built-in crc (the dedup lookup sequencing 1524 * needs to be fixed so the check code is already present 1525 * when dedup_lookup is called) 1526 */ 1527 crc = XXH64(data, pblksize, XXH_HAMMER2_SEED); 1528 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1529 1530 if (hammer2_debug & 0x40000) { 1531 kprintf("LOC %04x/4 %016jx\n", 1532 (int)(dedup - hmp->heur_dedup), 1533 crc); 1534 } 1535 1536 for (i = 0; i < 4; ++i) { 1537 off = dedup[i].data_off; 1538 cpu_ccfence(); 1539 if (dedup[i].data_crc != crc) 1540 continue; 1541 if ((1 << (int)(off & HAMMER2_OFF_MASK_RADIX)) != pblksize) 1542 continue; 1543 dio = hammer2_io_getquick(hmp, off, pblksize); 1544 if (dio) { 1545 dtmp = hammer2_io_data(dio, off), 1546 mask = hammer2_dedup_mask(dio, off, pblksize); 1547 if ((dio->dedup_alloc & mask) == mask && 1548 (dio->dedup_valid & mask) == mask && 1549 bcmp(data, dtmp, pblksize) == 0) { 1550 if (hammer2_debug & 0x40000) { 1551 kprintf("DEDUP SUCCESS %016jx\n", 1552 (intmax_t)off); 1553 } 1554 hammer2_io_putblk(&dio); 1555 *datap = NULL; 1556 dedup[i].ticks = ticks; /* update use */ 1557 atomic_add_long(&hammer2_iod_file_wdedup, 1558 pblksize); 1559 1560 return off; /* RETURN */ 1561 } 1562 hammer2_io_putblk(&dio); 1563 } 1564 } 1565 return 0; 1566 } 1567 1568 /* 1569 * Poof. Races are ok, if someone gets in and reuses a dedup offset 1570 * before or while we are clearing it they will also recover the freemap 1571 * entry (set it to fully allocated), so a bulkfree race can only set it 1572 * to a possibly-free state. 1573 * 1574 * XXX ok, well, not really sure races are ok but going to run with it 1575 * for the moment. 1576 */ 1577 void 1578 hammer2_dedup_clear(hammer2_dev_t *hmp) 1579 { 1580 int i; 1581 1582 for (i = 0; i < HAMMER2_DEDUP_HEUR_SIZE; ++i) { 1583 hmp->heur_dedup[i].data_off = 0; 1584 hmp->heur_dedup[i].ticks = ticks - 1; 1585 } 1586 } 1587