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/fcntl.h> 50 #include <sys/buf.h> 51 #include <sys/proc.h> 52 #include <sys/mount.h> 53 #include <sys/vnode.h> 54 #include <sys/mountctl.h> 55 #include <sys/dirent.h> 56 #include <sys/uio.h> 57 #include <sys/objcache.h> 58 #include <sys/event.h> 59 #include <sys/file.h> 60 #include <vfs/fifofs/fifo.h> 61 62 #include "hammer2.h" 63 #include "hammer2_lz4.h" 64 65 #include "zlib/hammer2_zlib.h" 66 67 struct objcache *cache_buffer_read; 68 struct objcache *cache_buffer_write; 69 70 /* 71 * Strategy code (async logical file buffer I/O from system) 72 * 73 * Except for the transaction init (which should normally not block), 74 * we essentially run the strategy operation asynchronously via a XOP. 75 * 76 * WARNING! The XOP deals with buffer synchronization. It is not synchronized 77 * to the current cpu. 78 * 79 * XXX This isn't supposed to be able to deadlock against vfs_sync vfsync() 80 * calls but it has in the past when multiple flushes are queued. 81 * 82 * XXX We currently terminate the transaction once we get a quorum, otherwise 83 * the frontend can stall, but this can leave the remaining nodes with 84 * a potential flush conflict. We need to delay flushes on those nodes 85 * until running transactions complete separately from the normal 86 * transaction sequencing. FIXME TODO. 87 */ 88 static int hammer2_strategy_read(struct vop_strategy_args *ap); 89 static int hammer2_strategy_write(struct vop_strategy_args *ap); 90 static void hammer2_strategy_read_completion(hammer2_chain_t *focus, 91 const char *data, struct bio *bio); 92 93 static hammer2_off_t hammer2_dedup_lookup(hammer2_dev_t *hmp, 94 char **datap, int pblksize); 95 96 int 97 hammer2_vop_strategy(struct vop_strategy_args *ap) 98 { 99 struct bio *biop; 100 struct buf *bp; 101 int error; 102 103 biop = ap->a_bio; 104 bp = biop->bio_buf; 105 106 switch(bp->b_cmd) { 107 case BUF_CMD_READ: 108 error = hammer2_strategy_read(ap); 109 ++hammer2_iod_file_read; 110 break; 111 case BUF_CMD_WRITE: 112 error = hammer2_strategy_write(ap); 113 ++hammer2_iod_file_write; 114 break; 115 default: 116 bp->b_error = error = EINVAL; 117 bp->b_flags |= B_ERROR; 118 biodone(biop); 119 break; 120 } 121 return (error); 122 } 123 124 /* 125 * Return the largest contiguous physical disk range for the logical 126 * request, in bytes. 127 * 128 * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb) 129 * 130 * Basically disabled, the logical buffer write thread has to deal with 131 * buffers one-at-a-time. Note that this should not prevent cluster_read() 132 * from reading-ahead, it simply prevents it from trying form a single 133 * cluster buffer for the logical request. H2 already uses 64KB buffers! 134 */ 135 int 136 hammer2_vop_bmap(struct vop_bmap_args *ap) 137 { 138 *ap->a_doffsetp = NOOFFSET; 139 if (ap->a_runp) 140 *ap->a_runp = 0; 141 if (ap->a_runb) 142 *ap->a_runb = 0; 143 return (EOPNOTSUPP); 144 } 145 146 /**************************************************************************** 147 * READ SUPPORT * 148 ****************************************************************************/ 149 /* 150 * Callback used in read path in case that a block is compressed with LZ4. 151 */ 152 static 153 void 154 hammer2_decompress_LZ4_callback(const char *data, u_int bytes, struct bio *bio) 155 { 156 struct buf *bp; 157 char *compressed_buffer; 158 int compressed_size; 159 int result; 160 161 bp = bio->bio_buf; 162 163 #if 0 164 if bio->bio_caller_info2.index && 165 bio->bio_caller_info1.uvalue32 != 166 crc32(bp->b_data, bp->b_bufsize) --- return error 167 #endif 168 169 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 170 compressed_size = *(const int *)data; 171 KKASSERT((uint32_t)compressed_size <= bytes - sizeof(int)); 172 173 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 174 result = LZ4_decompress_safe(__DECONST(char *, &data[sizeof(int)]), 175 compressed_buffer, 176 compressed_size, 177 bp->b_bufsize); 178 if (result < 0) { 179 kprintf("READ PATH: Error during decompression." 180 "bio %016jx/%d\n", 181 (intmax_t)bio->bio_offset, bytes); 182 /* make sure it isn't random garbage */ 183 bzero(compressed_buffer, bp->b_bufsize); 184 } 185 KKASSERT(result <= bp->b_bufsize); 186 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 187 if (result < bp->b_bufsize) 188 bzero(bp->b_data + result, bp->b_bufsize - result); 189 objcache_put(cache_buffer_read, compressed_buffer); 190 bp->b_resid = 0; 191 bp->b_flags |= B_AGE; 192 } 193 194 /* 195 * Callback used in read path in case that a block is compressed with ZLIB. 196 * It is almost identical to LZ4 callback, so in theory they can be unified, 197 * but we didn't want to make changes in bio structure for that. 198 */ 199 static 200 void 201 hammer2_decompress_ZLIB_callback(const char *data, u_int bytes, struct bio *bio) 202 { 203 struct buf *bp; 204 char *compressed_buffer; 205 z_stream strm_decompress; 206 int result; 207 int ret; 208 209 bp = bio->bio_buf; 210 211 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 212 strm_decompress.avail_in = 0; 213 strm_decompress.next_in = Z_NULL; 214 215 ret = inflateInit(&strm_decompress); 216 217 if (ret != Z_OK) 218 kprintf("HAMMER2 ZLIB: Fatal error in inflateInit.\n"); 219 220 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 221 strm_decompress.next_in = __DECONST(char *, data); 222 223 /* XXX supply proper size, subset of device bp */ 224 strm_decompress.avail_in = bytes; 225 strm_decompress.next_out = compressed_buffer; 226 strm_decompress.avail_out = bp->b_bufsize; 227 228 ret = inflate(&strm_decompress, Z_FINISH); 229 if (ret != Z_STREAM_END) { 230 kprintf("HAMMER2 ZLIB: Fatar error during decompression.\n"); 231 bzero(compressed_buffer, bp->b_bufsize); 232 } 233 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 234 result = bp->b_bufsize - strm_decompress.avail_out; 235 if (result < bp->b_bufsize) 236 bzero(bp->b_data + result, strm_decompress.avail_out); 237 objcache_put(cache_buffer_read, compressed_buffer); 238 ret = inflateEnd(&strm_decompress); 239 240 bp->b_resid = 0; 241 bp->b_flags |= B_AGE; 242 } 243 244 /* 245 * Logical buffer I/O, async read. 246 */ 247 static 248 int 249 hammer2_strategy_read(struct vop_strategy_args *ap) 250 { 251 hammer2_xop_strategy_t *xop; 252 struct bio *bio; 253 hammer2_inode_t *ip; 254 hammer2_key_t lbase; 255 256 bio = ap->a_bio; 257 ip = VTOI(ap->a_vp); 258 259 lbase = bio->bio_offset; 260 KKASSERT(((int)lbase & HAMMER2_PBUFMASK) == 0); 261 262 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_STRATEGY); 263 xop->finished = 0; 264 xop->bio = bio; 265 xop->lbase = lbase; 266 hammer2_mtx_init(&xop->lock, "h2bior"); 267 hammer2_xop_start(&xop->head, &hammer2_strategy_read_desc); 268 /* asynchronous completion */ 269 270 return(0); 271 } 272 273 /* 274 * Per-node XOP (threaded), do a synchronous lookup of the chain and 275 * its data. The frontend is asynchronous, so we are also responsible 276 * for racing to terminate the frontend. 277 */ 278 void 279 hammer2_xop_strategy_read(hammer2_xop_t *arg, void *scratch, int clindex) 280 { 281 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 282 hammer2_chain_t *parent; 283 hammer2_chain_t *chain; 284 hammer2_chain_t *focus; 285 hammer2_key_t key_dummy; 286 hammer2_key_t lbase; 287 struct bio *bio; 288 struct buf *bp; 289 const char *data; 290 int error; 291 292 /* 293 * Note that we can race completion of the bio supplied by 294 * the front-end so we cannot access it until we determine 295 * that we are the ones finishing it up. 296 */ 297 lbase = xop->lbase; 298 299 /* 300 * This is difficult to optimize. The logical buffer might be 301 * partially dirty (contain dummy zero-fill pages), which would 302 * mess up our crc calculation if we were to try a direct read. 303 * So for now we always double-buffer through the underlying 304 * storage. 305 * 306 * If not for the above problem we could conditionalize on 307 * (1) 64KB buffer, (2) one chain (not multi-master) and 308 * (3) !hammer2_double_buffer, and issue a direct read into the 309 * logical buffer. 310 */ 311 parent = hammer2_inode_chain(xop->head.ip1, clindex, 312 HAMMER2_RESOLVE_ALWAYS | 313 HAMMER2_RESOLVE_SHARED); 314 if (parent) { 315 chain = hammer2_chain_lookup(&parent, &key_dummy, 316 lbase, lbase, 317 &error, 318 HAMMER2_LOOKUP_ALWAYS | 319 HAMMER2_LOOKUP_SHARED); 320 if (chain) 321 error = chain->error; 322 } else { 323 error = HAMMER2_ERROR_EIO; 324 chain = NULL; 325 } 326 error = hammer2_xop_feed(&xop->head, chain, clindex, error); 327 if (chain) { 328 hammer2_chain_unlock(chain); 329 hammer2_chain_drop(chain); 330 } 331 if (parent) { 332 hammer2_chain_unlock(parent); 333 hammer2_chain_drop(parent); 334 } 335 chain = NULL; /* safety */ 336 parent = NULL; /* safety */ 337 338 /* 339 * Race to finish the frontend. First-to-complete. bio is only 340 * valid if we are determined to be the ones able to complete 341 * the operation. 342 */ 343 if (xop->finished) 344 return; 345 hammer2_mtx_ex(&xop->lock); 346 if (xop->finished) { 347 hammer2_mtx_unlock(&xop->lock); 348 return; 349 } 350 bio = xop->bio; 351 bp = bio->bio_buf; 352 bkvasync(bp); 353 354 /* 355 * Async operation has not completed and we now own the lock. 356 * Determine if we can complete the operation by issuing the 357 * frontend collection non-blocking. 358 * 359 * H2 double-buffers the data, setting B_NOTMETA on the logical 360 * buffer hints to the OS that the logical buffer should not be 361 * swapcached (since the device buffer can be). 362 * 363 * Also note that even for compressed data we would rather the 364 * kernel cache/swapcache device buffers more and (decompressed) 365 * logical buffers less, since that will significantly improve 366 * the amount of end-user data that can be cached. 367 * 368 * NOTE: The chain->data for xop->head.cluster.focus will be 369 * synchronized to the current cpu by xop_collect(), 370 * but other chains in the cluster might not be. 371 */ 372 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 373 374 switch(error) { 375 case 0: 376 xop->finished = 1; 377 hammer2_mtx_unlock(&xop->lock); 378 bp->b_flags |= B_NOTMETA; 379 focus = xop->head.cluster.focus; 380 data = hammer2_xop_gdata(&xop->head)->buf; 381 hammer2_strategy_read_completion(focus, data, xop->bio); 382 hammer2_xop_pdata(&xop->head); 383 biodone(bio); 384 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 385 break; 386 case HAMMER2_ERROR_ENOENT: 387 xop->finished = 1; 388 hammer2_mtx_unlock(&xop->lock); 389 bp->b_flags |= B_NOTMETA; 390 bp->b_resid = 0; 391 bp->b_error = 0; 392 bzero(bp->b_data, bp->b_bcount); 393 biodone(bio); 394 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 395 break; 396 case HAMMER2_ERROR_EINPROGRESS: 397 hammer2_mtx_unlock(&xop->lock); 398 break; 399 default: 400 kprintf("xop_strategy_read: error %08x loff=%016jx\n", 401 error, bp->b_loffset); 402 xop->finished = 1; 403 hammer2_mtx_unlock(&xop->lock); 404 bp->b_flags |= B_ERROR; 405 bp->b_error = EIO; 406 biodone(bio); 407 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 408 break; 409 } 410 } 411 412 static 413 void 414 hammer2_strategy_read_completion(hammer2_chain_t *focus, const char *data, 415 struct bio *bio) 416 { 417 struct buf *bp = bio->bio_buf; 418 419 if (focus->bref.type == HAMMER2_BREF_TYPE_INODE) { 420 /* 421 * Copy from in-memory inode structure. 422 */ 423 bcopy(((const hammer2_inode_data_t *)data)->u.data, 424 bp->b_data, HAMMER2_EMBEDDED_BYTES); 425 bzero(bp->b_data + HAMMER2_EMBEDDED_BYTES, 426 bp->b_bcount - HAMMER2_EMBEDDED_BYTES); 427 bp->b_resid = 0; 428 bp->b_error = 0; 429 } else if (focus->bref.type == HAMMER2_BREF_TYPE_DATA) { 430 /* 431 * Data is on-media, record for live dedup. Release the 432 * chain (try to free it) when done. The data is still 433 * cached by both the buffer cache in front and the 434 * block device behind us. This leaves more room in the 435 * LRU chain cache for meta-data chains which we really 436 * want to retain. 437 * 438 * NOTE: Deduplication cannot be safely recorded for 439 * records without a check code. 440 */ 441 hammer2_dedup_record(focus, NULL, data); 442 atomic_set_int(&focus->flags, HAMMER2_CHAIN_RELEASE); 443 444 /* 445 * Decompression and copy. 446 */ 447 switch (HAMMER2_DEC_COMP(focus->bref.methods)) { 448 case HAMMER2_COMP_LZ4: 449 hammer2_decompress_LZ4_callback(data, focus->bytes, 450 bio); 451 /* b_resid set by call */ 452 break; 453 case HAMMER2_COMP_ZLIB: 454 hammer2_decompress_ZLIB_callback(data, focus->bytes, 455 bio); 456 /* b_resid set by call */ 457 break; 458 case HAMMER2_COMP_NONE: 459 KKASSERT(focus->bytes <= bp->b_bcount); 460 bcopy(data, bp->b_data, focus->bytes); 461 if (focus->bytes < bp->b_bcount) { 462 bzero(bp->b_data + focus->bytes, 463 bp->b_bcount - focus->bytes); 464 } 465 bp->b_resid = 0; 466 bp->b_error = 0; 467 break; 468 default: 469 panic("hammer2_strategy_read_completion: " 470 "unknown compression type"); 471 } 472 } else { 473 panic("hammer2_strategy_read_completion: unknown bref type"); 474 } 475 } 476 477 /**************************************************************************** 478 * WRITE SUPPORT * 479 ****************************************************************************/ 480 481 /* 482 * Functions for compression in threads, 483 * from hammer2_vnops.c 484 */ 485 static void hammer2_write_file_core(char *data, hammer2_inode_t *ip, 486 hammer2_chain_t **parentp, 487 hammer2_key_t lbase, int ioflag, int pblksize, 488 hammer2_tid_t mtid, int *errorp); 489 static void hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 490 hammer2_chain_t **parentp, 491 hammer2_key_t lbase, int ioflag, int pblksize, 492 hammer2_tid_t mtid, int *errorp, 493 int comp_algo, int check_algo); 494 static void hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 495 hammer2_chain_t **parentp, 496 hammer2_key_t lbase, int ioflag, int pblksize, 497 hammer2_tid_t mtid, int *errorp, 498 int check_algo); 499 static int test_block_zeros(const char *buf, size_t bytes); 500 static void zero_write(char *data, hammer2_inode_t *ip, 501 hammer2_chain_t **parentp, 502 hammer2_key_t lbase, 503 hammer2_tid_t mtid, int *errorp); 504 static void hammer2_write_bp(hammer2_chain_t *chain, char *data, 505 int ioflag, int pblksize, 506 hammer2_tid_t mtid, int *errorp, 507 int check_algo); 508 509 int 510 hammer2_strategy_write(struct vop_strategy_args *ap) 511 { 512 hammer2_xop_strategy_t *xop; 513 hammer2_pfs_t *pmp; 514 struct bio *bio; 515 hammer2_inode_t *ip; 516 517 bio = ap->a_bio; 518 ip = VTOI(ap->a_vp); 519 pmp = ip->pmp; 520 521 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 522 hammer2_lwinprog_ref(pmp); 523 hammer2_trans_assert_strategy(pmp); 524 hammer2_trans_init(pmp, HAMMER2_TRANS_BUFCACHE); 525 526 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING | 527 HAMMER2_XOP_STRATEGY); 528 xop->finished = 0; 529 xop->bio = bio; 530 xop->lbase = bio->bio_offset; 531 hammer2_mtx_init(&xop->lock, "h2biow"); 532 hammer2_xop_start(&xop->head, &hammer2_strategy_write_desc); 533 /* asynchronous completion */ 534 535 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 536 537 return(0); 538 } 539 540 /* 541 * Per-node XOP (threaded). Write the logical buffer to the media. 542 * 543 * This is a bit problematic because there may be multiple target and 544 * any of them may be able to release the bp. In addition, if our 545 * particulr target is offline we don't want to block the bp (and thus 546 * the frontend). To accomplish this we copy the data to the per-thr 547 * scratch buffer. 548 */ 549 void 550 hammer2_xop_strategy_write(hammer2_xop_t *arg, void *scratch, int clindex) 551 { 552 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 553 hammer2_chain_t *parent; 554 hammer2_key_t lbase; 555 hammer2_inode_t *ip; 556 struct bio *bio; 557 struct buf *bp; 558 int error; 559 int lblksize; 560 int pblksize; 561 hammer2_off_t bio_offset; 562 char *bio_data; 563 564 /* 565 * We can only access the bp/bio if the frontend has not yet 566 * completed. 567 */ 568 if (xop->finished) 569 return; 570 hammer2_mtx_sh(&xop->lock); 571 if (xop->finished) { 572 hammer2_mtx_unlock(&xop->lock); 573 return; 574 } 575 576 lbase = xop->lbase; 577 bio = xop->bio; /* ephermal */ 578 bp = bio->bio_buf; /* ephermal */ 579 ip = xop->head.ip1; /* retained by ref */ 580 bio_offset = bio->bio_offset; 581 bio_data = scratch; 582 583 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 584 585 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 586 pblksize = hammer2_calc_physical(ip, lbase); 587 bkvasync(bp); 588 KKASSERT(lblksize <= MAXPHYS); 589 bcopy(bp->b_data, bio_data, lblksize); 590 591 hammer2_mtx_unlock(&xop->lock); 592 bp = NULL; /* safety, illegal to access after unlock */ 593 bio = NULL; /* safety, illegal to access after unlock */ 594 595 /* 596 * Actual operation 597 */ 598 parent = hammer2_inode_chain(ip, clindex, HAMMER2_RESOLVE_ALWAYS); 599 hammer2_write_file_core(bio_data, ip, &parent, 600 lbase, IO_ASYNC, pblksize, 601 xop->head.mtid, &error); 602 if (parent) { 603 hammer2_chain_unlock(parent); 604 hammer2_chain_drop(parent); 605 parent = NULL; /* safety */ 606 } 607 hammer2_xop_feed(&xop->head, NULL, clindex, error); 608 609 /* 610 * Try to complete the operation on behalf of the front-end. 611 */ 612 if (xop->finished) 613 return; 614 hammer2_mtx_ex(&xop->lock); 615 if (xop->finished) { 616 hammer2_mtx_unlock(&xop->lock); 617 return; 618 } 619 620 /* 621 * Async operation has not completed and we now own the lock. 622 * Determine if we can complete the operation by issuing the 623 * frontend collection non-blocking. 624 * 625 * H2 double-buffers the data, setting B_NOTMETA on the logical 626 * buffer hints to the OS that the logical buffer should not be 627 * swapcached (since the device buffer can be). 628 */ 629 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 630 631 if (error == HAMMER2_ERROR_EINPROGRESS) { 632 hammer2_mtx_unlock(&xop->lock); 633 return; 634 } 635 636 /* 637 * Async operation has completed. 638 */ 639 xop->finished = 1; 640 hammer2_mtx_unlock(&xop->lock); 641 642 bio = xop->bio; /* now owned by us */ 643 bp = bio->bio_buf; /* now owned by us */ 644 645 if (error == HAMMER2_ERROR_ENOENT || error == 0) { 646 bp->b_flags |= B_NOTMETA; 647 bp->b_resid = 0; 648 bp->b_error = 0; 649 biodone(bio); 650 } else { 651 kprintf("xop_strategy_write: error %d loff=%016jx\n", 652 error, bp->b_loffset); 653 bp->b_flags |= B_ERROR; 654 bp->b_error = EIO; 655 biodone(bio); 656 } 657 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 658 hammer2_trans_assert_strategy(ip->pmp); 659 hammer2_lwinprog_drop(ip->pmp); 660 hammer2_trans_done(ip->pmp, HAMMER2_TRANS_BUFCACHE); 661 } 662 663 /* 664 * Wait for pending I/O to complete 665 */ 666 void 667 hammer2_bioq_sync(hammer2_pfs_t *pmp) 668 { 669 hammer2_lwinprog_wait(pmp, 0); 670 } 671 672 /* 673 * Assign physical storage at (cparent, lbase), returning a suitable chain 674 * and setting *errorp appropriately. 675 * 676 * If no error occurs, the returned chain will be in a modified state. 677 * 678 * If an error occurs, the returned chain may or may not be NULL. If 679 * not-null any chain->error (if not 0) will also be rolled up into *errorp. 680 * So the caller only needs to test *errorp. 681 * 682 * cparent can wind up being anything. 683 * 684 * If datap is not NULL, *datap points to the real data we intend to write. 685 * If we can dedup the storage location we set *datap to NULL to indicate 686 * to the caller that a dedup occurred. 687 * 688 * NOTE: Special case for data embedded in inode. 689 */ 690 static 691 hammer2_chain_t * 692 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 693 hammer2_key_t lbase, int pblksize, 694 hammer2_tid_t mtid, char **datap, int *errorp) 695 { 696 hammer2_chain_t *chain; 697 hammer2_key_t key_dummy; 698 hammer2_off_t dedup_off; 699 int pradix = hammer2_getradix(pblksize); 700 701 /* 702 * Locate the chain associated with lbase, return a locked chain. 703 * However, do not instantiate any data reference (which utilizes a 704 * device buffer) because we will be using direct IO via the 705 * logical buffer cache buffer. 706 */ 707 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 708 709 chain = hammer2_chain_lookup(parentp, &key_dummy, 710 lbase, lbase, 711 errorp, 712 HAMMER2_LOOKUP_NODATA); 713 714 /* 715 * The lookup code should not return a DELETED chain to us, unless 716 * its a short-file embedded in the inode. Then it is possible for 717 * the lookup to return a deleted inode. 718 */ 719 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED) && 720 chain->bref.type != HAMMER2_BREF_TYPE_INODE) { 721 kprintf("assign physical deleted chain @ " 722 "%016jx (%016jx.%02x) ip %016jx\n", 723 lbase, chain->bref.data_off, chain->bref.type, 724 ip->meta.inum); 725 Debugger("bleh"); 726 } 727 728 if (chain == NULL) { 729 /* 730 * We found a hole, create a new chain entry. 731 * 732 * NOTE: DATA chains are created without device backing 733 * store (nor do we want any). 734 */ 735 dedup_off = hammer2_dedup_lookup((*parentp)->hmp, datap, 736 pblksize); 737 *errorp |= hammer2_chain_create(parentp, &chain, NULL, ip->pmp, 738 HAMMER2_ENC_CHECK(ip->meta.check_algo) | 739 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE), 740 lbase, HAMMER2_PBUFRADIX, 741 HAMMER2_BREF_TYPE_DATA, 742 pblksize, mtid, 743 dedup_off, 0); 744 if (chain == NULL) 745 goto failed; 746 /*ip->delta_dcount += pblksize;*/ 747 } else if (chain->error == 0) { 748 switch (chain->bref.type) { 749 case HAMMER2_BREF_TYPE_INODE: 750 /* 751 * The data is embedded in the inode, which requires 752 * a bit more finess. 753 */ 754 *errorp |= hammer2_chain_modify_ip(ip, chain, mtid, 0); 755 break; 756 case HAMMER2_BREF_TYPE_DATA: 757 dedup_off = hammer2_dedup_lookup(chain->hmp, datap, 758 pblksize); 759 if (chain->bytes != pblksize) { 760 *errorp |= hammer2_chain_resize(chain, 761 mtid, dedup_off, 762 pradix, 763 HAMMER2_MODIFY_OPTDATA); 764 if (*errorp) 765 break; 766 } 767 768 /* 769 * DATA buffers must be marked modified whether the 770 * data is in a logical buffer or not. We also have 771 * to make this call to fixup the chain data pointers 772 * after resizing in case this is an encrypted or 773 * compressed buffer. 774 */ 775 *errorp |= hammer2_chain_modify(chain, mtid, dedup_off, 776 HAMMER2_MODIFY_OPTDATA); 777 break; 778 default: 779 panic("hammer2_assign_physical: bad type"); 780 /* NOT REACHED */ 781 break; 782 } 783 } else { 784 *errorp = chain->error; 785 } 786 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 787 failed: 788 return (chain); 789 } 790 791 /* 792 * hammer2_write_file_core() 793 * 794 * The core write function which determines which path to take 795 * depending on compression settings. We also have to locate the 796 * related chains so we can calculate and set the check data for 797 * the blockref. 798 */ 799 static 800 void 801 hammer2_write_file_core(char *data, hammer2_inode_t *ip, 802 hammer2_chain_t **parentp, 803 hammer2_key_t lbase, int ioflag, int pblksize, 804 hammer2_tid_t mtid, int *errorp) 805 { 806 hammer2_chain_t *chain; 807 char *bdata; 808 809 *errorp = 0; 810 811 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 812 case HAMMER2_COMP_NONE: 813 /* 814 * We have to assign physical storage to the buffer 815 * we intend to dirty or write now to avoid deadlocks 816 * in the strategy code later. 817 * 818 * This can return NOOFFSET for inode-embedded data. 819 * The strategy code will take care of it in that case. 820 */ 821 bdata = data; 822 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 823 mtid, &bdata, errorp); 824 if (*errorp) { 825 /* skip modifications */ 826 } else if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 827 hammer2_inode_data_t *wipdata; 828 829 wipdata = &chain->data->ipdata; 830 KKASSERT(wipdata->meta.op_flags & 831 HAMMER2_OPFLAG_DIRECTDATA); 832 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 833 ++hammer2_iod_file_wembed; 834 } else if (bdata == NULL) { 835 /* 836 * Copy of data already present on-media. 837 */ 838 chain->bref.methods = 839 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 840 HAMMER2_ENC_CHECK(ip->meta.check_algo); 841 hammer2_chain_setcheck(chain, data); 842 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 843 } else { 844 hammer2_write_bp(chain, data, ioflag, pblksize, 845 mtid, errorp, ip->meta.check_algo); 846 } 847 if (chain) { 848 hammer2_chain_unlock(chain); 849 hammer2_chain_drop(chain); 850 } 851 break; 852 case HAMMER2_COMP_AUTOZERO: 853 /* 854 * Check for zero-fill only 855 */ 856 hammer2_zero_check_and_write(data, ip, parentp, 857 lbase, ioflag, pblksize, 858 mtid, errorp, 859 ip->meta.check_algo); 860 break; 861 case HAMMER2_COMP_LZ4: 862 case HAMMER2_COMP_ZLIB: 863 default: 864 /* 865 * Check for zero-fill and attempt compression. 866 */ 867 hammer2_compress_and_write(data, ip, parentp, 868 lbase, ioflag, pblksize, 869 mtid, errorp, 870 ip->meta.comp_algo, 871 ip->meta.check_algo); 872 break; 873 } 874 } 875 876 /* 877 * Helper 878 * 879 * Generic function that will perform the compression in compression 880 * write path. The compression algorithm is determined by the settings 881 * obtained from inode. 882 */ 883 static 884 void 885 hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 886 hammer2_chain_t **parentp, 887 hammer2_key_t lbase, int ioflag, int pblksize, 888 hammer2_tid_t mtid, int *errorp, int comp_algo, int check_algo) 889 { 890 hammer2_chain_t *chain; 891 int comp_size; 892 int comp_block_size; 893 char *comp_buffer; 894 char *bdata; 895 896 /* 897 * An all-zeros write creates a hole unless the check code 898 * is disabled. When the check code is disabled all writes 899 * are done in-place, including any all-zeros writes. 900 * 901 * NOTE: A snapshot will still force a copy-on-write 902 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 903 */ 904 if (check_algo != HAMMER2_CHECK_NONE && 905 test_block_zeros(data, pblksize)) { 906 zero_write(data, ip, parentp, lbase, mtid, errorp); 907 return; 908 } 909 910 /* 911 * Compression requested. Try to compress the block. We store 912 * the data normally if we cannot sufficiently compress it. 913 * 914 * We have a heuristic to detect files which are mostly 915 * uncompressable and avoid the compression attempt in that 916 * case. If the compression heuristic is turned off, we always 917 * try to compress. 918 */ 919 comp_size = 0; 920 comp_buffer = NULL; 921 922 KKASSERT(pblksize / 2 <= 32768); 923 924 if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0 || 925 hammer2_always_compress) { 926 z_stream strm_compress; 927 int comp_level; 928 int ret; 929 930 switch(HAMMER2_DEC_ALGO(comp_algo)) { 931 case HAMMER2_COMP_LZ4: 932 /* 933 * We need to prefix with the size, LZ4 934 * doesn't do it for us. Add the related 935 * overhead. 936 * 937 * NOTE: The LZ4 code seems to assume at least an 938 * 8-byte buffer size granularity and may 939 * overrun the buffer if given a 4-byte 940 * granularity. 941 */ 942 comp_buffer = objcache_get(cache_buffer_write, 943 M_INTWAIT); 944 comp_size = LZ4_compress_limitedOutput( 945 data, 946 &comp_buffer[sizeof(int)], 947 pblksize, 948 pblksize / 2 - sizeof(int64_t)); 949 *(int *)comp_buffer = comp_size; 950 if (comp_size) 951 comp_size += sizeof(int); 952 break; 953 case HAMMER2_COMP_ZLIB: 954 comp_level = HAMMER2_DEC_LEVEL(comp_algo); 955 if (comp_level == 0) 956 comp_level = 6; /* default zlib compression */ 957 else if (comp_level < 6) 958 comp_level = 6; 959 else if (comp_level > 9) 960 comp_level = 9; 961 ret = deflateInit(&strm_compress, comp_level); 962 if (ret != Z_OK) { 963 kprintf("HAMMER2 ZLIB: fatal error " 964 "on deflateInit.\n"); 965 } 966 967 comp_buffer = objcache_get(cache_buffer_write, 968 M_INTWAIT); 969 strm_compress.next_in = data; 970 strm_compress.avail_in = pblksize; 971 strm_compress.next_out = comp_buffer; 972 strm_compress.avail_out = pblksize / 2; 973 ret = deflate(&strm_compress, Z_FINISH); 974 if (ret == Z_STREAM_END) { 975 comp_size = pblksize / 2 - 976 strm_compress.avail_out; 977 } else { 978 comp_size = 0; 979 } 980 ret = deflateEnd(&strm_compress); 981 break; 982 default: 983 kprintf("Error: Unknown compression method.\n"); 984 kprintf("Comp_method = %d.\n", comp_algo); 985 break; 986 } 987 } 988 989 if (comp_size == 0) { 990 /* 991 * compression failed or turned off 992 */ 993 comp_block_size = pblksize; /* safety */ 994 if (++ip->comp_heuristic > 128) 995 ip->comp_heuristic = 8; 996 } else { 997 /* 998 * compression succeeded 999 */ 1000 ip->comp_heuristic = 0; 1001 if (comp_size <= 1024) { 1002 comp_block_size = 1024; 1003 } else if (comp_size <= 2048) { 1004 comp_block_size = 2048; 1005 } else if (comp_size <= 4096) { 1006 comp_block_size = 4096; 1007 } else if (comp_size <= 8192) { 1008 comp_block_size = 8192; 1009 } else if (comp_size <= 16384) { 1010 comp_block_size = 16384; 1011 } else if (comp_size <= 32768) { 1012 comp_block_size = 32768; 1013 } else { 1014 panic("hammer2: WRITE PATH: " 1015 "Weird comp_size value."); 1016 /* NOT REACHED */ 1017 comp_block_size = pblksize; 1018 } 1019 1020 /* 1021 * Must zero the remainder or dedup (which operates on a 1022 * physical block basis) will not find matches. 1023 */ 1024 if (comp_size < comp_block_size) { 1025 bzero(comp_buffer + comp_size, 1026 comp_block_size - comp_size); 1027 } 1028 } 1029 1030 /* 1031 * Assign physical storage, bdata will be set to NULL if a live-dedup 1032 * was successful. 1033 */ 1034 bdata = comp_size ? comp_buffer : data; 1035 chain = hammer2_assign_physical(ip, parentp, lbase, comp_block_size, 1036 mtid, &bdata, errorp); 1037 1038 if (*errorp) { 1039 goto done; 1040 } 1041 1042 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1043 hammer2_inode_data_t *wipdata; 1044 1045 *errorp = hammer2_chain_modify_ip(ip, chain, mtid, 0); 1046 if (*errorp == 0) { 1047 wipdata = &chain->data->ipdata; 1048 KKASSERT(wipdata->meta.op_flags & 1049 HAMMER2_OPFLAG_DIRECTDATA); 1050 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1051 ++hammer2_iod_file_wembed; 1052 } 1053 } else if (bdata == NULL) { 1054 /* 1055 * Live deduplication, a copy of the data is already present 1056 * on the media. 1057 */ 1058 if (comp_size) { 1059 chain->bref.methods = 1060 HAMMER2_ENC_COMP(comp_algo) + 1061 HAMMER2_ENC_CHECK(check_algo); 1062 } else { 1063 chain->bref.methods = 1064 HAMMER2_ENC_COMP( 1065 HAMMER2_COMP_NONE) + 1066 HAMMER2_ENC_CHECK(check_algo); 1067 } 1068 bdata = comp_size ? comp_buffer : data; 1069 hammer2_chain_setcheck(chain, bdata); 1070 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1071 } else { 1072 hammer2_io_t *dio; 1073 1074 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1075 1076 switch(chain->bref.type) { 1077 case HAMMER2_BREF_TYPE_INODE: 1078 panic("hammer2_compress_and_write: unexpected inode\n"); 1079 break; 1080 case HAMMER2_BREF_TYPE_DATA: 1081 /* 1082 * Optimize out the read-before-write 1083 * if possible. 1084 */ 1085 *errorp = hammer2_io_newnz(chain->hmp, 1086 chain->bref.type, 1087 chain->bref.data_off, 1088 chain->bytes, 1089 &dio); 1090 if (*errorp) { 1091 hammer2_io_brelse(&dio); 1092 kprintf("hammer2: WRITE PATH: " 1093 "dbp bread error\n"); 1094 break; 1095 } 1096 bdata = hammer2_io_data(dio, chain->bref.data_off); 1097 1098 /* 1099 * When loading the block make sure we don't 1100 * leave garbage after the compressed data. 1101 */ 1102 if (comp_size) { 1103 chain->bref.methods = 1104 HAMMER2_ENC_COMP(comp_algo) + 1105 HAMMER2_ENC_CHECK(check_algo); 1106 bcopy(comp_buffer, bdata, comp_block_size); 1107 } else { 1108 chain->bref.methods = 1109 HAMMER2_ENC_COMP( 1110 HAMMER2_COMP_NONE) + 1111 HAMMER2_ENC_CHECK(check_algo); 1112 bcopy(data, bdata, pblksize); 1113 } 1114 1115 /* 1116 * The flush code doesn't calculate check codes for 1117 * file data (doing so can result in excessive I/O), 1118 * so we do it here. 1119 */ 1120 hammer2_chain_setcheck(chain, bdata); 1121 1122 /* 1123 * Device buffer is now valid, chain is no longer in 1124 * the initial state. 1125 * 1126 * (No blockref table worries with file data) 1127 */ 1128 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1129 hammer2_dedup_record(chain, dio, bdata); 1130 1131 /* Now write the related bdp. */ 1132 if (ioflag & IO_SYNC) { 1133 /* 1134 * Synchronous I/O requested. 1135 */ 1136 hammer2_io_bwrite(&dio); 1137 /* 1138 } else if ((ioflag & IO_DIRECT) && 1139 loff + n == pblksize) { 1140 hammer2_io_bdwrite(&dio); 1141 */ 1142 } else if (ioflag & IO_ASYNC) { 1143 hammer2_io_bawrite(&dio); 1144 } else { 1145 hammer2_io_bdwrite(&dio); 1146 } 1147 break; 1148 default: 1149 panic("hammer2_compress_and_write: bad chain type %d\n", 1150 chain->bref.type); 1151 /* NOT REACHED */ 1152 break; 1153 } 1154 } 1155 done: 1156 if (chain) { 1157 hammer2_chain_unlock(chain); 1158 hammer2_chain_drop(chain); 1159 } 1160 if (comp_buffer) 1161 objcache_put(cache_buffer_write, comp_buffer); 1162 } 1163 1164 /* 1165 * Helper 1166 * 1167 * Function that performs zero-checking and writing without compression, 1168 * it corresponds to default zero-checking path. 1169 */ 1170 static 1171 void 1172 hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 1173 hammer2_chain_t **parentp, 1174 hammer2_key_t lbase, int ioflag, int pblksize, 1175 hammer2_tid_t mtid, int *errorp, 1176 int check_algo) 1177 { 1178 hammer2_chain_t *chain; 1179 char *bdata; 1180 1181 if (check_algo != HAMMER2_CHECK_NONE && 1182 test_block_zeros(data, pblksize)) { 1183 /* 1184 * An all-zeros write creates a hole unless the check code 1185 * is disabled. When the check code is disabled all writes 1186 * are done in-place, including any all-zeros writes. 1187 * 1188 * NOTE: A snapshot will still force a copy-on-write 1189 * (see the HAMMER2_CHECK_NONE in hammer2_chain.c). 1190 */ 1191 zero_write(data, ip, parentp, lbase, mtid, errorp); 1192 } else { 1193 /* 1194 * Normal write (bdata set to NULL if de-duplicated) 1195 */ 1196 bdata = data; 1197 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 1198 mtid, &bdata, errorp); 1199 if (*errorp) { 1200 /* do nothing */ 1201 } else if (bdata) { 1202 hammer2_write_bp(chain, data, ioflag, pblksize, 1203 mtid, errorp, check_algo); 1204 } else { 1205 /* dedup occurred */ 1206 chain->bref.methods = 1207 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1208 HAMMER2_ENC_CHECK(check_algo); 1209 hammer2_chain_setcheck(chain, data); 1210 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1211 } 1212 if (chain) { 1213 hammer2_chain_unlock(chain); 1214 hammer2_chain_drop(chain); 1215 } 1216 } 1217 } 1218 1219 /* 1220 * Helper 1221 * 1222 * A function to test whether a block of data contains only zeros, 1223 * returns TRUE (non-zero) if the block is all zeros. 1224 */ 1225 static 1226 int 1227 test_block_zeros(const char *buf, size_t bytes) 1228 { 1229 size_t i; 1230 1231 for (i = 0; i < bytes; i += sizeof(long)) { 1232 if (*(const long *)(buf + i) != 0) 1233 return (0); 1234 } 1235 return (1); 1236 } 1237 1238 /* 1239 * Helper 1240 * 1241 * Function to "write" a block that contains only zeros. 1242 */ 1243 static 1244 void 1245 zero_write(char *data, hammer2_inode_t *ip, 1246 hammer2_chain_t **parentp, 1247 hammer2_key_t lbase, hammer2_tid_t mtid, int *errorp) 1248 { 1249 hammer2_chain_t *chain; 1250 hammer2_key_t key_dummy; 1251 1252 chain = hammer2_chain_lookup(parentp, &key_dummy, 1253 lbase, lbase, 1254 errorp, 1255 HAMMER2_LOOKUP_NODATA); 1256 if (chain) { 1257 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1258 hammer2_inode_data_t *wipdata; 1259 1260 if (*errorp == 0) { 1261 *errorp = hammer2_chain_modify_ip(ip, chain, 1262 mtid, 0); 1263 } 1264 if (*errorp == 0) { 1265 wipdata = &chain->data->ipdata; 1266 KKASSERT(wipdata->meta.op_flags & 1267 HAMMER2_OPFLAG_DIRECTDATA); 1268 bzero(wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1269 ++hammer2_iod_file_wembed; 1270 } 1271 } else { 1272 /* chain->error ok for deletion */ 1273 hammer2_chain_delete(*parentp, chain, 1274 mtid, HAMMER2_DELETE_PERMANENT); 1275 ++hammer2_iod_file_wzero; 1276 } 1277 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 1278 hammer2_chain_unlock(chain); 1279 hammer2_chain_drop(chain); 1280 } else { 1281 ++hammer2_iod_file_wzero; 1282 } 1283 } 1284 1285 /* 1286 * Helper 1287 * 1288 * Function to write the data as it is, without performing any sort of 1289 * compression. This function is used in path without compression and 1290 * default zero-checking path. 1291 */ 1292 static 1293 void 1294 hammer2_write_bp(hammer2_chain_t *chain, char *data, int ioflag, 1295 int pblksize, 1296 hammer2_tid_t mtid, int *errorp, int check_algo) 1297 { 1298 hammer2_inode_data_t *wipdata; 1299 hammer2_io_t *dio; 1300 char *bdata; 1301 int error; 1302 1303 error = 0; /* XXX TODO below */ 1304 1305 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1306 1307 switch(chain->bref.type) { 1308 case HAMMER2_BREF_TYPE_INODE: 1309 wipdata = &chain->data->ipdata; 1310 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1311 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1312 error = 0; 1313 ++hammer2_iod_file_wembed; 1314 break; 1315 case HAMMER2_BREF_TYPE_DATA: 1316 error = hammer2_io_newnz(chain->hmp, 1317 chain->bref.type, 1318 chain->bref.data_off, 1319 chain->bytes, &dio); 1320 if (error) { 1321 hammer2_io_bqrelse(&dio); 1322 kprintf("hammer2: WRITE PATH: " 1323 "dbp bread error\n"); 1324 break; 1325 } 1326 bdata = hammer2_io_data(dio, chain->bref.data_off); 1327 1328 chain->bref.methods = HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1329 HAMMER2_ENC_CHECK(check_algo); 1330 bcopy(data, bdata, chain->bytes); 1331 1332 /* 1333 * The flush code doesn't calculate check codes for 1334 * file data (doing so can result in excessive I/O), 1335 * so we do it here. 1336 */ 1337 hammer2_chain_setcheck(chain, bdata); 1338 1339 /* 1340 * Device buffer is now valid, chain is no longer in 1341 * the initial state. 1342 * 1343 * (No blockref table worries with file data) 1344 */ 1345 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1346 hammer2_dedup_record(chain, dio, bdata); 1347 1348 if (ioflag & IO_SYNC) { 1349 /* 1350 * Synchronous I/O requested. 1351 */ 1352 hammer2_io_bwrite(&dio); 1353 /* 1354 } else if ((ioflag & IO_DIRECT) && 1355 loff + n == pblksize) { 1356 hammer2_io_bdwrite(&dio); 1357 */ 1358 } else if (ioflag & IO_ASYNC) { 1359 hammer2_io_bawrite(&dio); 1360 } else { 1361 hammer2_io_bdwrite(&dio); 1362 } 1363 break; 1364 default: 1365 panic("hammer2_write_bp: bad chain type %d\n", 1366 chain->bref.type); 1367 /* NOT REACHED */ 1368 error = 0; 1369 break; 1370 } 1371 *errorp = error; 1372 } 1373 1374 /* 1375 * LIVE DEDUP HEURISTICS 1376 * 1377 * Record media and crc information for possible dedup operation. Note 1378 * that the dedup mask bits must also be set in the related DIO for a dedup 1379 * to be fully validated (which is handled in the freemap allocation code). 1380 * 1381 * WARNING! This code is SMP safe but the heuristic allows SMP collisions. 1382 * All fields must be loaded into locals and validated. 1383 * 1384 * WARNING! Should only be used for file data and directory entries, 1385 * hammer2_chain_modify() only checks for the dedup case on data 1386 * chains. Also, dedup data can only be recorded for committed 1387 * chains (so NOT strategy writes which can undergo further 1388 * modification after the fact!). 1389 */ 1390 void 1391 hammer2_dedup_record(hammer2_chain_t *chain, hammer2_io_t *dio, 1392 const char *data) 1393 { 1394 hammer2_dev_t *hmp; 1395 hammer2_dedup_t *dedup; 1396 uint64_t crc; 1397 uint64_t mask; 1398 int best = 0; 1399 int i; 1400 int dticks; 1401 1402 /* 1403 * We can only record a dedup if we have media data to test against. 1404 * If dedup is not enabled, return early, which allows a chain to 1405 * remain marked MODIFIED (which might have benefits in special 1406 * situations, though typically it does not). 1407 */ 1408 if (hammer2_dedup_enable == 0) 1409 return; 1410 if (dio == NULL) { 1411 dio = chain->dio; 1412 if (dio == NULL) 1413 return; 1414 } 1415 1416 hmp = chain->hmp; 1417 1418 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 1419 case HAMMER2_CHECK_ISCSI32: 1420 /* 1421 * XXX use the built-in crc (the dedup lookup sequencing 1422 * needs to be fixed so the check code is already present 1423 * when dedup_lookup is called) 1424 */ 1425 #if 0 1426 crc = (uint64_t)(uint32_t)chain->bref.check.iscsi32.value; 1427 #endif 1428 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1429 break; 1430 case HAMMER2_CHECK_XXHASH64: 1431 crc = chain->bref.check.xxhash64.value; 1432 break; 1433 case HAMMER2_CHECK_SHA192: 1434 /* 1435 * XXX use the built-in crc (the dedup lookup sequencing 1436 * needs to be fixed so the check code is already present 1437 * when dedup_lookup is called) 1438 */ 1439 #if 0 1440 crc = ((uint64_t *)chain->bref.check.sha192.data)[0] ^ 1441 ((uint64_t *)chain->bref.check.sha192.data)[1] ^ 1442 ((uint64_t *)chain->bref.check.sha192.data)[2]; 1443 #endif 1444 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1445 break; 1446 default: 1447 /* 1448 * Cannot dedup without a check code 1449 * 1450 * NOTE: In particular, CHECK_NONE allows a sector to be 1451 * overwritten without copy-on-write, recording 1452 * a dedup block for a CHECK_NONE object would be 1453 * a disaster! 1454 */ 1455 return; 1456 } 1457 1458 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DEDUPABLE); 1459 1460 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1461 for (i = 0; i < 4; ++i) { 1462 if (dedup[i].data_crc == crc) { 1463 best = i; 1464 break; 1465 } 1466 dticks = (int)(dedup[i].ticks - dedup[best].ticks); 1467 if (dticks < 0 || dticks > hz * 60 * 30) 1468 best = i; 1469 } 1470 dedup += best; 1471 if (hammer2_debug & 0x40000) { 1472 kprintf("REC %04x %016jx %016jx\n", 1473 (int)(dedup - hmp->heur_dedup), 1474 crc, 1475 chain->bref.data_off); 1476 } 1477 dedup->ticks = ticks; 1478 dedup->data_off = chain->bref.data_off; 1479 dedup->data_crc = crc; 1480 1481 /* 1482 * Set the valid bits for the dedup only after we know the data 1483 * buffer has been updated. The alloc bits were set (and the valid 1484 * bits cleared) when the media was allocated. 1485 * 1486 * This is done in two stages becuase the bulkfree code can race 1487 * the gap between allocation and data population. Both masks must 1488 * be set before a bcmp/dedup operation is able to use the block. 1489 */ 1490 mask = hammer2_dedup_mask(dio, chain->bref.data_off, chain->bytes); 1491 atomic_set_64(&dio->dedup_valid, mask); 1492 1493 #if 0 1494 /* 1495 * XXX removed. MODIFIED is an integral part of the flush code, 1496 * lets not just clear it 1497 */ 1498 /* 1499 * Once we record the dedup the chain must be marked clean to 1500 * prevent reuse of the underlying block. Remember that this 1501 * write occurs when the buffer cache is flushed (i.e. on sync(), 1502 * fsync(), filesystem periodic sync, or when the kernel needs to 1503 * flush a buffer), and not whenever the user write()s. 1504 */ 1505 if (chain->flags & HAMMER2_CHAIN_MODIFIED) { 1506 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); 1507 atomic_add_long(&hammer2_count_modified_chains, -1); 1508 if (chain->pmp) 1509 hammer2_pfs_memory_wakeup(chain->pmp, -1); 1510 } 1511 #endif 1512 } 1513 1514 static 1515 hammer2_off_t 1516 hammer2_dedup_lookup(hammer2_dev_t *hmp, char **datap, int pblksize) 1517 { 1518 hammer2_dedup_t *dedup; 1519 hammer2_io_t *dio; 1520 hammer2_off_t off; 1521 uint64_t crc; 1522 uint64_t mask; 1523 char *data; 1524 char *dtmp; 1525 int i; 1526 1527 if (hammer2_dedup_enable == 0) 1528 return 0; 1529 data = *datap; 1530 if (data == NULL) 1531 return 0; 1532 1533 /* 1534 * XXX use the built-in crc (the dedup lookup sequencing 1535 * needs to be fixed so the check code is already present 1536 * when dedup_lookup is called) 1537 */ 1538 crc = XXH64(data, pblksize, XXH_HAMMER2_SEED); 1539 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1540 1541 if (hammer2_debug & 0x40000) { 1542 kprintf("LOC %04x/4 %016jx\n", 1543 (int)(dedup - hmp->heur_dedup), 1544 crc); 1545 } 1546 1547 for (i = 0; i < 4; ++i) { 1548 off = dedup[i].data_off; 1549 cpu_ccfence(); 1550 if (dedup[i].data_crc != crc) 1551 continue; 1552 if ((1 << (int)(off & HAMMER2_OFF_MASK_RADIX)) != pblksize) 1553 continue; 1554 dio = hammer2_io_getquick(hmp, off, pblksize); 1555 if (dio) { 1556 dtmp = hammer2_io_data(dio, off), 1557 mask = hammer2_dedup_mask(dio, off, pblksize); 1558 if ((dio->dedup_alloc & mask) == mask && 1559 (dio->dedup_valid & mask) == mask && 1560 bcmp(data, dtmp, pblksize) == 0) { 1561 if (hammer2_debug & 0x40000) { 1562 kprintf("DEDUP SUCCESS %016jx\n", 1563 (intmax_t)off); 1564 } 1565 hammer2_io_putblk(&dio); 1566 *datap = NULL; 1567 dedup[i].ticks = ticks; /* update use */ 1568 atomic_add_long(&hammer2_iod_file_wdedup, 1569 pblksize); 1570 1571 return off; /* RETURN */ 1572 } 1573 hammer2_io_putblk(&dio); 1574 } 1575 } 1576 return 0; 1577 } 1578 1579 /* 1580 * Poof. Races are ok, if someone gets in and reuses a dedup offset 1581 * before or while we are clearing it they will also recover the freemap 1582 * entry (set it to fully allocated), so a bulkfree race can only set it 1583 * to a possibly-free state. 1584 * 1585 * XXX ok, well, not really sure races are ok but going to run with it 1586 * for the moment. 1587 */ 1588 void 1589 hammer2_dedup_clear(hammer2_dev_t *hmp) 1590 { 1591 int i; 1592 1593 for (i = 0; i < HAMMER2_DEDUP_HEUR_SIZE; ++i) { 1594 hmp->heur_dedup[i].data_off = 0; 1595 hmp->heur_dedup[i].ticks = ticks - 1; 1596 } 1597 } 1598