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. 426 * 427 * NOTE: Deduplication cannot be safely recorded for 428 * records without a check code. 429 */ 430 hammer2_dedup_record(focus, NULL, data); 431 atomic_set_int(&focus->flags, HAMMER2_CHAIN_RELEASE); 432 433 /* 434 * Decompression and copy. 435 */ 436 switch (HAMMER2_DEC_COMP(focus->bref.methods)) { 437 case HAMMER2_COMP_LZ4: 438 hammer2_decompress_LZ4_callback(data, focus->bytes, 439 bio); 440 /* b_resid set by call */ 441 break; 442 case HAMMER2_COMP_ZLIB: 443 hammer2_decompress_ZLIB_callback(data, focus->bytes, 444 bio); 445 /* b_resid set by call */ 446 break; 447 case HAMMER2_COMP_NONE: 448 KKASSERT(focus->bytes <= bp->b_bcount); 449 bcopy(data, bp->b_data, focus->bytes); 450 if (focus->bytes < bp->b_bcount) { 451 bzero(bp->b_data + focus->bytes, 452 bp->b_bcount - focus->bytes); 453 } 454 bp->b_resid = 0; 455 bp->b_error = 0; 456 break; 457 default: 458 panic("hammer2_strategy_read_completion: " 459 "unknown compression type"); 460 } 461 } else { 462 panic("hammer2_strategy_read_completion: unknown bref type"); 463 } 464 } 465 466 /**************************************************************************** 467 * WRITE SUPPORT * 468 ****************************************************************************/ 469 470 /* 471 * Functions for compression in threads, 472 * from hammer2_vnops.c 473 */ 474 static void hammer2_write_file_core(char *data, hammer2_inode_t *ip, 475 hammer2_chain_t **parentp, 476 hammer2_key_t lbase, int ioflag, int pblksize, 477 hammer2_tid_t mtid, int *errorp); 478 static void hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 479 hammer2_chain_t **parentp, 480 hammer2_key_t lbase, int ioflag, int pblksize, 481 hammer2_tid_t mtid, int *errorp, 482 int comp_algo, int check_algo); 483 static void hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 484 hammer2_chain_t **parentp, 485 hammer2_key_t lbase, int ioflag, int pblksize, 486 hammer2_tid_t mtid, int *errorp, 487 int check_algo); 488 static int test_block_zeros(const char *buf, size_t bytes); 489 static void zero_write(char *data, hammer2_inode_t *ip, 490 hammer2_chain_t **parentp, 491 hammer2_key_t lbase, 492 hammer2_tid_t mtid, int *errorp); 493 static void hammer2_write_bp(hammer2_chain_t *chain, char *data, 494 int ioflag, int pblksize, 495 hammer2_tid_t mtid, int *errorp, 496 int check_algo); 497 498 int 499 hammer2_strategy_write(struct vop_strategy_args *ap) 500 { 501 hammer2_xop_strategy_t *xop; 502 hammer2_pfs_t *pmp; 503 struct bio *bio; 504 hammer2_inode_t *ip; 505 506 bio = ap->a_bio; 507 ip = VTOI(ap->a_vp); 508 pmp = ip->pmp; 509 510 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 511 hammer2_lwinprog_ref(pmp); 512 hammer2_trans_assert_strategy(pmp); 513 hammer2_trans_init(pmp, HAMMER2_TRANS_BUFCACHE); 514 515 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING | 516 HAMMER2_XOP_STRATEGY); 517 xop->finished = 0; 518 xop->bio = bio; 519 xop->lbase = bio->bio_offset; 520 hammer2_mtx_init(&xop->lock, "h2biow"); 521 hammer2_xop_start(&xop->head, &hammer2_strategy_write_desc); 522 /* asynchronous completion */ 523 524 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 525 526 return(0); 527 } 528 529 /* 530 * Per-node XOP (threaded). Write the logical buffer to the media. 531 * 532 * This is a bit problematic because there may be multiple target and 533 * any of them may be able to release the bp. In addition, if our 534 * particulr target is offline we don't want to block the bp (and thus 535 * the frontend). To accomplish this we copy the data to the per-thr 536 * scratch buffer. 537 */ 538 void 539 hammer2_xop_strategy_write(hammer2_xop_t *arg, void *scratch, int clindex) 540 { 541 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 542 hammer2_chain_t *parent; 543 hammer2_key_t lbase; 544 hammer2_inode_t *ip; 545 struct bio *bio; 546 struct buf *bp; 547 int error; 548 int lblksize; 549 int pblksize; 550 char *bio_data; 551 552 /* 553 * We can only access the bp/bio if the frontend has not yet 554 * completed. 555 */ 556 if (xop->finished) 557 return; 558 hammer2_mtx_sh(&xop->lock); 559 if (xop->finished) { 560 hammer2_mtx_unlock(&xop->lock); 561 return; 562 } 563 564 lbase = xop->lbase; 565 bio = xop->bio; /* ephermal */ 566 bp = bio->bio_buf; /* ephermal */ 567 ip = xop->head.ip1; /* retained by ref */ 568 bio_data = scratch; 569 570 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 571 572 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 573 pblksize = hammer2_calc_physical(ip, lbase); 574 bkvasync(bp); 575 KKASSERT(lblksize <= MAXPHYS); 576 bcopy(bp->b_data, bio_data, lblksize); 577 578 hammer2_mtx_unlock(&xop->lock); 579 bp = NULL; /* safety, illegal to access after unlock */ 580 bio = NULL; /* safety, illegal to access after unlock */ 581 582 /* 583 * Actual operation 584 */ 585 parent = hammer2_inode_chain(ip, clindex, HAMMER2_RESOLVE_ALWAYS); 586 hammer2_write_file_core(bio_data, ip, &parent, 587 lbase, IO_ASYNC, pblksize, 588 xop->head.mtid, &error); 589 if (parent) { 590 hammer2_chain_unlock(parent); 591 hammer2_chain_drop(parent); 592 parent = NULL; /* safety */ 593 } 594 hammer2_xop_feed(&xop->head, NULL, clindex, error); 595 596 /* 597 * Try to complete the operation on behalf of the front-end. 598 */ 599 if (xop->finished) 600 return; 601 hammer2_mtx_ex(&xop->lock); 602 if (xop->finished) { 603 hammer2_mtx_unlock(&xop->lock); 604 return; 605 } 606 607 /* 608 * Async operation has not completed and we now own the lock. 609 * Determine if we can complete the operation by issuing the 610 * frontend collection non-blocking. 611 * 612 * H2 double-buffers the data, setting B_NOTMETA on the logical 613 * buffer hints to the OS that the logical buffer should not be 614 * swapcached (since the device buffer can be). 615 */ 616 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 617 618 if (error == HAMMER2_ERROR_EINPROGRESS) { 619 hammer2_mtx_unlock(&xop->lock); 620 return; 621 } 622 623 /* 624 * Async operation has completed. 625 */ 626 xop->finished = 1; 627 hammer2_mtx_unlock(&xop->lock); 628 629 bio = xop->bio; /* now owned by us */ 630 bp = bio->bio_buf; /* now owned by us */ 631 632 if (error == HAMMER2_ERROR_ENOENT || error == 0) { 633 bp->b_flags |= B_NOTMETA; 634 bp->b_resid = 0; 635 bp->b_error = 0; 636 biodone(bio); 637 } else { 638 kprintf("xop_strategy_write: error %d loff=%016jx\n", 639 error, (intmax_t)bp->b_loffset); 640 bp->b_flags |= B_ERROR; 641 bp->b_error = EIO; 642 biodone(bio); 643 } 644 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 645 hammer2_trans_assert_strategy(ip->pmp); 646 hammer2_lwinprog_drop(ip->pmp); 647 hammer2_trans_done(ip->pmp, HAMMER2_TRANS_BUFCACHE); 648 } 649 650 /* 651 * Wait for pending I/O to complete 652 */ 653 void 654 hammer2_bioq_sync(hammer2_pfs_t *pmp) 655 { 656 hammer2_lwinprog_wait(pmp, 0); 657 } 658 659 /* 660 * Assign physical storage at (cparent, lbase), returning a suitable chain 661 * and setting *errorp appropriately. 662 * 663 * If no error occurs, the returned chain will be in a modified state. 664 * 665 * If an error occurs, the returned chain may or may not be NULL. If 666 * not-null any chain->error (if not 0) will also be rolled up into *errorp. 667 * So the caller only needs to test *errorp. 668 * 669 * cparent can wind up being anything. 670 * 671 * If datap is not NULL, *datap points to the real data we intend to write. 672 * If we can dedup the storage location we set *datap to NULL to indicate 673 * to the caller that a dedup occurred. 674 * 675 * NOTE: Special case for data embedded in inode. 676 */ 677 static 678 hammer2_chain_t * 679 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 680 hammer2_key_t lbase, int pblksize, 681 hammer2_tid_t mtid, char **datap, int *errorp) 682 { 683 hammer2_chain_t *chain; 684 hammer2_key_t key_dummy; 685 hammer2_off_t dedup_off; 686 int pradix = hammer2_getradix(pblksize); 687 688 /* 689 * Locate the chain associated with lbase, return a locked chain. 690 * However, do not instantiate any data reference (which utilizes a 691 * device buffer) because we will be using direct IO via the 692 * logical buffer cache buffer. 693 */ 694 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 695 696 chain = hammer2_chain_lookup(parentp, &key_dummy, 697 lbase, lbase, 698 errorp, 699 HAMMER2_LOOKUP_NODATA); 700 701 /* 702 * The lookup code should not return a DELETED chain to us, unless 703 * its a short-file embedded in the inode. Then it is possible for 704 * the lookup to return a deleted inode. 705 */ 706 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED) && 707 chain->bref.type != HAMMER2_BREF_TYPE_INODE) { 708 kprintf("assign physical deleted chain @ " 709 "%016jx (%016jx.%02x) ip %016jx\n", 710 lbase, chain->bref.data_off, chain->bref.type, 711 ip->meta.inum); 712 Debugger("bleh"); 713 } 714 715 if (chain == NULL) { 716 /* 717 * We found a hole, create a new chain entry. 718 * 719 * NOTE: DATA chains are created without device backing 720 * store (nor do we want any). 721 */ 722 dedup_off = hammer2_dedup_lookup((*parentp)->hmp, datap, 723 pblksize); 724 *errorp |= hammer2_chain_create(parentp, &chain, NULL, ip->pmp, 725 HAMMER2_ENC_CHECK(ip->meta.check_algo) | 726 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE), 727 lbase, HAMMER2_PBUFRADIX, 728 HAMMER2_BREF_TYPE_DATA, 729 pblksize, mtid, 730 dedup_off, 0); 731 if (chain == NULL) 732 goto failed; 733 /*ip->delta_dcount += pblksize;*/ 734 } else if (chain->error == 0) { 735 switch (chain->bref.type) { 736 case HAMMER2_BREF_TYPE_INODE: 737 /* 738 * The data is embedded in the inode, which requires 739 * a bit more finess. 740 */ 741 *errorp |= hammer2_chain_modify_ip(ip, chain, mtid, 0); 742 break; 743 case HAMMER2_BREF_TYPE_DATA: 744 dedup_off = hammer2_dedup_lookup(chain->hmp, datap, 745 pblksize); 746 if (chain->bytes != pblksize) { 747 *errorp |= hammer2_chain_resize(chain, 748 mtid, dedup_off, 749 pradix, 750 HAMMER2_MODIFY_OPTDATA); 751 if (*errorp) 752 break; 753 } 754 755 /* 756 * DATA buffers must be marked modified whether the 757 * data is in a logical buffer or not. We also have 758 * to make this call to fixup the chain data pointers 759 * after resizing in case this is an encrypted or 760 * compressed buffer. 761 */ 762 *errorp |= hammer2_chain_modify(chain, mtid, dedup_off, 763 HAMMER2_MODIFY_OPTDATA); 764 break; 765 default: 766 panic("hammer2_assign_physical: bad type"); 767 /* NOT REACHED */ 768 break; 769 } 770 } else { 771 *errorp = chain->error; 772 } 773 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 774 failed: 775 return (chain); 776 } 777 778 /* 779 * hammer2_write_file_core() 780 * 781 * The core write function which determines which path to take 782 * depending on compression settings. We also have to locate the 783 * related chains so we can calculate and set the check data for 784 * the blockref. 785 */ 786 static 787 void 788 hammer2_write_file_core(char *data, hammer2_inode_t *ip, 789 hammer2_chain_t **parentp, 790 hammer2_key_t lbase, int ioflag, int pblksize, 791 hammer2_tid_t mtid, int *errorp) 792 { 793 hammer2_chain_t *chain; 794 char *bdata; 795 796 *errorp = 0; 797 798 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 799 case HAMMER2_COMP_NONE: 800 /* 801 * We have to assign physical storage to the buffer 802 * we intend to dirty or write now to avoid deadlocks 803 * in the strategy code later. 804 * 805 * This can return NOOFFSET for inode-embedded data. 806 * The strategy code will take care of it in that case. 807 */ 808 bdata = data; 809 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 810 mtid, &bdata, errorp); 811 if (*errorp) { 812 /* skip modifications */ 813 } else if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 814 hammer2_inode_data_t *wipdata; 815 816 wipdata = &chain->data->ipdata; 817 KKASSERT(wipdata->meta.op_flags & 818 HAMMER2_OPFLAG_DIRECTDATA); 819 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 820 ++hammer2_iod_file_wembed; 821 } else if (bdata == NULL) { 822 /* 823 * Copy of data already present on-media. 824 */ 825 chain->bref.methods = 826 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 827 HAMMER2_ENC_CHECK(ip->meta.check_algo); 828 hammer2_chain_setcheck(chain, data); 829 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 830 } else { 831 hammer2_write_bp(chain, data, ioflag, pblksize, 832 mtid, errorp, ip->meta.check_algo); 833 } 834 if (chain) { 835 hammer2_chain_unlock(chain); 836 hammer2_chain_drop(chain); 837 } 838 break; 839 case HAMMER2_COMP_AUTOZERO: 840 /* 841 * Check for zero-fill only 842 */ 843 hammer2_zero_check_and_write(data, ip, parentp, 844 lbase, ioflag, pblksize, 845 mtid, errorp, 846 ip->meta.check_algo); 847 break; 848 case HAMMER2_COMP_LZ4: 849 case HAMMER2_COMP_ZLIB: 850 default: 851 /* 852 * Check for zero-fill and attempt compression. 853 */ 854 hammer2_compress_and_write(data, ip, parentp, 855 lbase, ioflag, pblksize, 856 mtid, errorp, 857 ip->meta.comp_algo, 858 ip->meta.check_algo); 859 break; 860 } 861 } 862 863 /* 864 * Helper 865 * 866 * Generic function that will perform the compression in compression 867 * write path. The compression algorithm is determined by the settings 868 * obtained from inode. 869 */ 870 static 871 void 872 hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 873 hammer2_chain_t **parentp, 874 hammer2_key_t lbase, int ioflag, int pblksize, 875 hammer2_tid_t mtid, int *errorp, int comp_algo, int check_algo) 876 { 877 hammer2_chain_t *chain; 878 int comp_size; 879 int comp_block_size; 880 char *comp_buffer; 881 char *bdata; 882 883 /* 884 * An all-zeros write creates a hole unless the check code 885 * is disabled. When the check code is disabled all writes 886 * are done in-place, including any all-zeros writes. 887 * 888 * NOTE: A snapshot will still force a copy-on-write 889 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 890 */ 891 if (check_algo != HAMMER2_CHECK_NONE && 892 test_block_zeros(data, pblksize)) { 893 zero_write(data, ip, parentp, lbase, mtid, errorp); 894 return; 895 } 896 897 /* 898 * Compression requested. Try to compress the block. We store 899 * the data normally if we cannot sufficiently compress it. 900 * 901 * We have a heuristic to detect files which are mostly 902 * uncompressable and avoid the compression attempt in that 903 * case. If the compression heuristic is turned off, we always 904 * try to compress. 905 */ 906 comp_size = 0; 907 comp_buffer = NULL; 908 909 KKASSERT(pblksize / 2 <= 32768); 910 911 if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0 || 912 hammer2_always_compress) { 913 z_stream strm_compress; 914 int comp_level; 915 int ret; 916 917 switch(HAMMER2_DEC_ALGO(comp_algo)) { 918 case HAMMER2_COMP_LZ4: 919 /* 920 * We need to prefix with the size, LZ4 921 * doesn't do it for us. Add the related 922 * overhead. 923 * 924 * NOTE: The LZ4 code seems to assume at least an 925 * 8-byte buffer size granularity and may 926 * overrun the buffer if given a 4-byte 927 * granularity. 928 */ 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(int64_t)); 936 *(int *)comp_buffer = comp_size; 937 if (comp_size) 938 comp_size += sizeof(int); 939 break; 940 case HAMMER2_COMP_ZLIB: 941 comp_level = HAMMER2_DEC_LEVEL(comp_algo); 942 if (comp_level == 0) 943 comp_level = 6; /* default zlib compression */ 944 else if (comp_level < 6) 945 comp_level = 6; 946 else if (comp_level > 9) 947 comp_level = 9; 948 ret = deflateInit(&strm_compress, comp_level); 949 if (ret != Z_OK) { 950 kprintf("HAMMER2 ZLIB: fatal error " 951 "on deflateInit.\n"); 952 } 953 954 comp_buffer = objcache_get(cache_buffer_write, 955 M_INTWAIT); 956 strm_compress.next_in = data; 957 strm_compress.avail_in = pblksize; 958 strm_compress.next_out = comp_buffer; 959 strm_compress.avail_out = pblksize / 2; 960 ret = deflate(&strm_compress, Z_FINISH); 961 if (ret == Z_STREAM_END) { 962 comp_size = pblksize / 2 - 963 strm_compress.avail_out; 964 } else { 965 comp_size = 0; 966 } 967 ret = deflateEnd(&strm_compress); 968 break; 969 default: 970 kprintf("Error: Unknown compression method.\n"); 971 kprintf("Comp_method = %d.\n", comp_algo); 972 break; 973 } 974 } 975 976 if (comp_size == 0) { 977 /* 978 * compression failed or turned off 979 */ 980 comp_block_size = pblksize; /* safety */ 981 if (++ip->comp_heuristic > 128) 982 ip->comp_heuristic = 8; 983 } else { 984 /* 985 * compression succeeded 986 */ 987 ip->comp_heuristic = 0; 988 if (comp_size <= 1024) { 989 comp_block_size = 1024; 990 } else if (comp_size <= 2048) { 991 comp_block_size = 2048; 992 } else if (comp_size <= 4096) { 993 comp_block_size = 4096; 994 } else if (comp_size <= 8192) { 995 comp_block_size = 8192; 996 } else if (comp_size <= 16384) { 997 comp_block_size = 16384; 998 } else if (comp_size <= 32768) { 999 comp_block_size = 32768; 1000 } else { 1001 panic("hammer2: WRITE PATH: " 1002 "Weird comp_size value."); 1003 /* NOT REACHED */ 1004 comp_block_size = pblksize; 1005 } 1006 1007 /* 1008 * Must zero the remainder or dedup (which operates on a 1009 * physical block basis) will not find matches. 1010 */ 1011 if (comp_size < comp_block_size) { 1012 bzero(comp_buffer + comp_size, 1013 comp_block_size - comp_size); 1014 } 1015 } 1016 1017 /* 1018 * Assign physical storage, bdata will be set to NULL if a live-dedup 1019 * was successful. 1020 */ 1021 bdata = comp_size ? comp_buffer : data; 1022 chain = hammer2_assign_physical(ip, parentp, lbase, comp_block_size, 1023 mtid, &bdata, errorp); 1024 1025 if (*errorp) { 1026 goto done; 1027 } 1028 1029 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1030 hammer2_inode_data_t *wipdata; 1031 1032 *errorp = hammer2_chain_modify_ip(ip, chain, mtid, 0); 1033 if (*errorp == 0) { 1034 wipdata = &chain->data->ipdata; 1035 KKASSERT(wipdata->meta.op_flags & 1036 HAMMER2_OPFLAG_DIRECTDATA); 1037 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1038 ++hammer2_iod_file_wembed; 1039 } 1040 } else if (bdata == NULL) { 1041 /* 1042 * Live deduplication, a copy of the data is already present 1043 * on the media. 1044 */ 1045 if (comp_size) { 1046 chain->bref.methods = 1047 HAMMER2_ENC_COMP(comp_algo) + 1048 HAMMER2_ENC_CHECK(check_algo); 1049 } else { 1050 chain->bref.methods = 1051 HAMMER2_ENC_COMP( 1052 HAMMER2_COMP_NONE) + 1053 HAMMER2_ENC_CHECK(check_algo); 1054 } 1055 bdata = comp_size ? comp_buffer : data; 1056 hammer2_chain_setcheck(chain, bdata); 1057 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1058 } else { 1059 hammer2_io_t *dio; 1060 1061 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1062 1063 switch(chain->bref.type) { 1064 case HAMMER2_BREF_TYPE_INODE: 1065 panic("hammer2_compress_and_write: unexpected inode\n"); 1066 break; 1067 case HAMMER2_BREF_TYPE_DATA: 1068 /* 1069 * Optimize out the read-before-write 1070 * if possible. 1071 */ 1072 *errorp = hammer2_io_newnz(chain->hmp, 1073 chain->bref.type, 1074 chain->bref.data_off, 1075 chain->bytes, 1076 &dio); 1077 if (*errorp) { 1078 hammer2_io_brelse(&dio); 1079 kprintf("hammer2: WRITE PATH: " 1080 "dbp bread error\n"); 1081 break; 1082 } 1083 bdata = hammer2_io_data(dio, chain->bref.data_off); 1084 1085 /* 1086 * When loading the block make sure we don't 1087 * leave garbage after the compressed data. 1088 */ 1089 if (comp_size) { 1090 chain->bref.methods = 1091 HAMMER2_ENC_COMP(comp_algo) + 1092 HAMMER2_ENC_CHECK(check_algo); 1093 bcopy(comp_buffer, bdata, comp_block_size); 1094 } else { 1095 chain->bref.methods = 1096 HAMMER2_ENC_COMP( 1097 HAMMER2_COMP_NONE) + 1098 HAMMER2_ENC_CHECK(check_algo); 1099 bcopy(data, bdata, pblksize); 1100 } 1101 1102 /* 1103 * The flush code doesn't calculate check codes for 1104 * file data (doing so can result in excessive I/O), 1105 * so we do it here. 1106 */ 1107 hammer2_chain_setcheck(chain, bdata); 1108 1109 /* 1110 * Device buffer is now valid, chain is no longer in 1111 * the initial state. 1112 * 1113 * (No blockref table worries with file data) 1114 */ 1115 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1116 hammer2_dedup_record(chain, dio, bdata); 1117 1118 /* Now write the related bdp. */ 1119 if (ioflag & IO_SYNC) { 1120 /* 1121 * Synchronous I/O requested. 1122 */ 1123 hammer2_io_bwrite(&dio); 1124 /* 1125 } else if ((ioflag & IO_DIRECT) && 1126 loff + n == pblksize) { 1127 hammer2_io_bdwrite(&dio); 1128 */ 1129 } else if (ioflag & IO_ASYNC) { 1130 hammer2_io_bawrite(&dio); 1131 } else { 1132 hammer2_io_bdwrite(&dio); 1133 } 1134 break; 1135 default: 1136 panic("hammer2_compress_and_write: bad chain type %d\n", 1137 chain->bref.type); 1138 /* NOT REACHED */ 1139 break; 1140 } 1141 } 1142 done: 1143 if (chain) { 1144 hammer2_chain_unlock(chain); 1145 hammer2_chain_drop(chain); 1146 } 1147 if (comp_buffer) 1148 objcache_put(cache_buffer_write, comp_buffer); 1149 } 1150 1151 /* 1152 * Helper 1153 * 1154 * Function that performs zero-checking and writing without compression, 1155 * it corresponds to default zero-checking path. 1156 */ 1157 static 1158 void 1159 hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 1160 hammer2_chain_t **parentp, 1161 hammer2_key_t lbase, int ioflag, int pblksize, 1162 hammer2_tid_t mtid, int *errorp, 1163 int check_algo) 1164 { 1165 hammer2_chain_t *chain; 1166 char *bdata; 1167 1168 if (check_algo != HAMMER2_CHECK_NONE && 1169 test_block_zeros(data, pblksize)) { 1170 /* 1171 * An all-zeros write creates a hole unless the check code 1172 * is disabled. When the check code is disabled all writes 1173 * are done in-place, including any all-zeros writes. 1174 * 1175 * NOTE: A snapshot will still force a copy-on-write 1176 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 1177 */ 1178 zero_write(data, ip, parentp, lbase, mtid, errorp); 1179 } else { 1180 /* 1181 * Normal write (bdata set to NULL if de-duplicated) 1182 */ 1183 bdata = data; 1184 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 1185 mtid, &bdata, errorp); 1186 if (*errorp) { 1187 /* do nothing */ 1188 } else if (bdata) { 1189 hammer2_write_bp(chain, data, ioflag, pblksize, 1190 mtid, errorp, check_algo); 1191 } else { 1192 /* dedup occurred */ 1193 chain->bref.methods = 1194 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1195 HAMMER2_ENC_CHECK(check_algo); 1196 hammer2_chain_setcheck(chain, data); 1197 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1198 } 1199 if (chain) { 1200 hammer2_chain_unlock(chain); 1201 hammer2_chain_drop(chain); 1202 } 1203 } 1204 } 1205 1206 /* 1207 * Helper 1208 * 1209 * A function to test whether a block of data contains only zeros, 1210 * returns TRUE (non-zero) if the block is all zeros. 1211 */ 1212 static 1213 int 1214 test_block_zeros(const char *buf, size_t bytes) 1215 { 1216 size_t i; 1217 1218 for (i = 0; i < bytes; i += sizeof(long)) { 1219 if (*(const long *)(buf + i) != 0) 1220 return (0); 1221 } 1222 return (1); 1223 } 1224 1225 /* 1226 * Helper 1227 * 1228 * Function to "write" a block that contains only zeros. 1229 */ 1230 static 1231 void 1232 zero_write(char *data, hammer2_inode_t *ip, 1233 hammer2_chain_t **parentp, 1234 hammer2_key_t lbase, hammer2_tid_t mtid, int *errorp) 1235 { 1236 hammer2_chain_t *chain; 1237 hammer2_key_t key_dummy; 1238 1239 chain = hammer2_chain_lookup(parentp, &key_dummy, 1240 lbase, lbase, 1241 errorp, 1242 HAMMER2_LOOKUP_NODATA); 1243 if (chain) { 1244 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1245 hammer2_inode_data_t *wipdata; 1246 1247 if (*errorp == 0) { 1248 *errorp = hammer2_chain_modify_ip(ip, chain, 1249 mtid, 0); 1250 } 1251 if (*errorp == 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 } 1258 } else { 1259 /* chain->error ok for deletion */ 1260 hammer2_chain_delete(*parentp, chain, 1261 mtid, HAMMER2_DELETE_PERMANENT); 1262 ++hammer2_iod_file_wzero; 1263 } 1264 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 1265 hammer2_chain_unlock(chain); 1266 hammer2_chain_drop(chain); 1267 } else { 1268 ++hammer2_iod_file_wzero; 1269 } 1270 } 1271 1272 /* 1273 * Helper 1274 * 1275 * Function to write the data as it is, without performing any sort of 1276 * compression. This function is used in path without compression and 1277 * default zero-checking path. 1278 */ 1279 static 1280 void 1281 hammer2_write_bp(hammer2_chain_t *chain, char *data, int ioflag, 1282 int pblksize, 1283 hammer2_tid_t mtid, int *errorp, int check_algo) 1284 { 1285 hammer2_inode_data_t *wipdata; 1286 hammer2_io_t *dio; 1287 char *bdata; 1288 int error; 1289 1290 error = 0; /* XXX TODO below */ 1291 1292 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1293 1294 switch(chain->bref.type) { 1295 case HAMMER2_BREF_TYPE_INODE: 1296 wipdata = &chain->data->ipdata; 1297 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1298 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1299 error = 0; 1300 ++hammer2_iod_file_wembed; 1301 break; 1302 case HAMMER2_BREF_TYPE_DATA: 1303 error = hammer2_io_newnz(chain->hmp, 1304 chain->bref.type, 1305 chain->bref.data_off, 1306 chain->bytes, &dio); 1307 if (error) { 1308 hammer2_io_bqrelse(&dio); 1309 kprintf("hammer2: WRITE PATH: " 1310 "dbp bread error\n"); 1311 break; 1312 } 1313 bdata = hammer2_io_data(dio, chain->bref.data_off); 1314 1315 chain->bref.methods = HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1316 HAMMER2_ENC_CHECK(check_algo); 1317 bcopy(data, bdata, chain->bytes); 1318 1319 /* 1320 * The flush code doesn't calculate check codes for 1321 * file data (doing so can result in excessive I/O), 1322 * so we do it here. 1323 */ 1324 hammer2_chain_setcheck(chain, bdata); 1325 1326 /* 1327 * Device buffer is now valid, chain is no longer in 1328 * the initial state. 1329 * 1330 * (No blockref table worries with file data) 1331 */ 1332 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1333 hammer2_dedup_record(chain, dio, bdata); 1334 1335 if (ioflag & IO_SYNC) { 1336 /* 1337 * Synchronous I/O requested. 1338 */ 1339 hammer2_io_bwrite(&dio); 1340 /* 1341 } else if ((ioflag & IO_DIRECT) && 1342 loff + n == pblksize) { 1343 hammer2_io_bdwrite(&dio); 1344 */ 1345 } else if (ioflag & IO_ASYNC) { 1346 hammer2_io_bawrite(&dio); 1347 } else { 1348 hammer2_io_bdwrite(&dio); 1349 } 1350 break; 1351 default: 1352 panic("hammer2_write_bp: bad chain type %d\n", 1353 chain->bref.type); 1354 /* NOT REACHED */ 1355 error = 0; 1356 break; 1357 } 1358 *errorp = error; 1359 } 1360 1361 /* 1362 * LIVE DEDUP HEURISTICS 1363 * 1364 * Record media and crc information for possible dedup operation. Note 1365 * that the dedup mask bits must also be set in the related DIO for a dedup 1366 * to be fully validated (which is handled in the freemap allocation code). 1367 * 1368 * WARNING! This code is SMP safe but the heuristic allows SMP collisions. 1369 * All fields must be loaded into locals and validated. 1370 * 1371 * WARNING! Should only be used for file data and directory entries, 1372 * hammer2_chain_modify() only checks for the dedup case on data 1373 * chains. Also, dedup data can only be recorded for committed 1374 * chains (so NOT strategy writes which can undergo further 1375 * modification after the fact!). 1376 */ 1377 void 1378 hammer2_dedup_record(hammer2_chain_t *chain, hammer2_io_t *dio, 1379 const char *data) 1380 { 1381 hammer2_dev_t *hmp; 1382 hammer2_dedup_t *dedup; 1383 uint64_t crc; 1384 uint64_t mask; 1385 int best = 0; 1386 int i; 1387 int dticks; 1388 1389 /* 1390 * We can only record a dedup if we have media data to test against. 1391 * If dedup is not enabled, return early, which allows a chain to 1392 * remain marked MODIFIED (which might have benefits in special 1393 * situations, though typically it does not). 1394 */ 1395 if (hammer2_dedup_enable == 0) 1396 return; 1397 if (dio == NULL) { 1398 dio = chain->dio; 1399 if (dio == NULL) 1400 return; 1401 } 1402 1403 hmp = chain->hmp; 1404 1405 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 1406 case HAMMER2_CHECK_ISCSI32: 1407 /* 1408 * XXX use the built-in crc (the dedup lookup sequencing 1409 * needs to be fixed so the check code is already present 1410 * when dedup_lookup is called) 1411 */ 1412 #if 0 1413 crc = (uint64_t)(uint32_t)chain->bref.check.iscsi32.value; 1414 #endif 1415 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1416 break; 1417 case HAMMER2_CHECK_XXHASH64: 1418 crc = chain->bref.check.xxhash64.value; 1419 break; 1420 case HAMMER2_CHECK_SHA192: 1421 /* 1422 * XXX use the built-in crc (the dedup lookup sequencing 1423 * needs to be fixed so the check code is already present 1424 * when dedup_lookup is called) 1425 */ 1426 #if 0 1427 crc = ((uint64_t *)chain->bref.check.sha192.data)[0] ^ 1428 ((uint64_t *)chain->bref.check.sha192.data)[1] ^ 1429 ((uint64_t *)chain->bref.check.sha192.data)[2]; 1430 #endif 1431 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1432 break; 1433 default: 1434 /* 1435 * Cannot dedup without a check code 1436 * 1437 * NOTE: In particular, CHECK_NONE allows a sector to be 1438 * overwritten without copy-on-write, recording 1439 * a dedup block for a CHECK_NONE object would be 1440 * a disaster! 1441 */ 1442 return; 1443 } 1444 1445 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DEDUPABLE); 1446 1447 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1448 for (i = 0; i < 4; ++i) { 1449 if (dedup[i].data_crc == crc) { 1450 best = i; 1451 break; 1452 } 1453 dticks = (int)(dedup[i].ticks - dedup[best].ticks); 1454 if (dticks < 0 || dticks > hz * 60 * 30) 1455 best = i; 1456 } 1457 dedup += best; 1458 if (hammer2_debug & 0x40000) { 1459 kprintf("REC %04x %016jx %016jx\n", 1460 (int)(dedup - hmp->heur_dedup), 1461 crc, 1462 chain->bref.data_off); 1463 } 1464 dedup->ticks = ticks; 1465 dedup->data_off = chain->bref.data_off; 1466 dedup->data_crc = crc; 1467 1468 /* 1469 * Set the valid bits for the dedup only after we know the data 1470 * buffer has been updated. The alloc bits were set (and the valid 1471 * bits cleared) when the media was allocated. 1472 * 1473 * This is done in two stages becuase the bulkfree code can race 1474 * the gap between allocation and data population. Both masks must 1475 * be set before a bcmp/dedup operation is able to use the block. 1476 */ 1477 mask = hammer2_dedup_mask(dio, chain->bref.data_off, chain->bytes); 1478 atomic_set_64(&dio->dedup_valid, mask); 1479 1480 #if 0 1481 /* 1482 * XXX removed. MODIFIED is an integral part of the flush code, 1483 * lets not just clear it 1484 */ 1485 /* 1486 * Once we record the dedup the chain must be marked clean to 1487 * prevent reuse of the underlying block. Remember that this 1488 * write occurs when the buffer cache is flushed (i.e. on sync(), 1489 * fsync(), filesystem periodic sync, or when the kernel needs to 1490 * flush a buffer), and not whenever the user write()s. 1491 */ 1492 if (chain->flags & HAMMER2_CHAIN_MODIFIED) { 1493 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); 1494 atomic_add_long(&hammer2_count_modified_chains, -1); 1495 if (chain->pmp) 1496 hammer2_pfs_memory_wakeup(chain->pmp, -1); 1497 } 1498 #endif 1499 } 1500 1501 static 1502 hammer2_off_t 1503 hammer2_dedup_lookup(hammer2_dev_t *hmp, char **datap, int pblksize) 1504 { 1505 hammer2_dedup_t *dedup; 1506 hammer2_io_t *dio; 1507 hammer2_off_t off; 1508 uint64_t crc; 1509 uint64_t mask; 1510 char *data; 1511 char *dtmp; 1512 int i; 1513 1514 if (hammer2_dedup_enable == 0) 1515 return 0; 1516 data = *datap; 1517 if (data == NULL) 1518 return 0; 1519 1520 /* 1521 * XXX use the built-in crc (the dedup lookup sequencing 1522 * needs to be fixed so the check code is already present 1523 * when dedup_lookup is called) 1524 */ 1525 crc = XXH64(data, pblksize, XXH_HAMMER2_SEED); 1526 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1527 1528 if (hammer2_debug & 0x40000) { 1529 kprintf("LOC %04x/4 %016jx\n", 1530 (int)(dedup - hmp->heur_dedup), 1531 crc); 1532 } 1533 1534 for (i = 0; i < 4; ++i) { 1535 off = dedup[i].data_off; 1536 cpu_ccfence(); 1537 if (dedup[i].data_crc != crc) 1538 continue; 1539 if ((1 << (int)(off & HAMMER2_OFF_MASK_RADIX)) != pblksize) 1540 continue; 1541 dio = hammer2_io_getquick(hmp, off, pblksize); 1542 if (dio) { 1543 dtmp = hammer2_io_data(dio, off), 1544 mask = hammer2_dedup_mask(dio, off, pblksize); 1545 if ((dio->dedup_alloc & mask) == mask && 1546 (dio->dedup_valid & mask) == mask && 1547 bcmp(data, dtmp, pblksize) == 0) { 1548 if (hammer2_debug & 0x40000) { 1549 kprintf("DEDUP SUCCESS %016jx\n", 1550 (intmax_t)off); 1551 } 1552 hammer2_io_putblk(&dio); 1553 *datap = NULL; 1554 dedup[i].ticks = ticks; /* update use */ 1555 atomic_add_long(&hammer2_iod_file_wdedup, 1556 pblksize); 1557 1558 return off; /* RETURN */ 1559 } 1560 hammer2_io_putblk(&dio); 1561 } 1562 } 1563 return 0; 1564 } 1565 1566 /* 1567 * Poof. Races are ok, if someone gets in and reuses a dedup offset 1568 * before or while we are clearing it they will also recover the freemap 1569 * entry (set it to fully allocated), so a bulkfree race can only set it 1570 * to a possibly-free state. 1571 * 1572 * XXX ok, well, not really sure races are ok but going to run with it 1573 * for the moment. 1574 */ 1575 void 1576 hammer2_dedup_clear(hammer2_dev_t *hmp) 1577 { 1578 int i; 1579 1580 for (i = 0; i < HAMMER2_DEDUP_HEUR_SIZE; ++i) { 1581 hmp->heur_dedup[i].data_off = 0; 1582 hmp->heur_dedup[i].ticks = ticks - 1; 1583 } 1584 } 1585