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/namei.h> 53 #include <sys/mount.h> 54 #include <sys/vnode.h> 55 #include <sys/mountctl.h> 56 #include <sys/dirent.h> 57 #include <sys/uio.h> 58 #include <sys/objcache.h> 59 #include <sys/event.h> 60 #include <sys/file.h> 61 #include <vfs/fifofs/fifo.h> 62 63 #include "hammer2.h" 64 #include "hammer2_lz4.h" 65 66 #include "zlib/hammer2_zlib.h" 67 68 struct objcache *cache_buffer_read; 69 struct objcache *cache_buffer_write; 70 71 /* 72 * Strategy code (async logical file buffer I/O from system) 73 * 74 * Except for the transaction init (which should normally not block), 75 * we essentially run the strategy operation asynchronously via a XOP. 76 * 77 * WARNING! The XOP deals with buffer synchronization. It is not synchronized 78 * to the current cpu. 79 * 80 * XXX This isn't supposed to be able to deadlock against vfs_sync vfsync() 81 * calls but it has in the past when multiple flushes are queued. 82 * 83 * XXX We currently terminate the transaction once we get a quorum, otherwise 84 * the frontend can stall, but this can leave the remaining nodes with 85 * a potential flush conflict. We need to delay flushes on those nodes 86 * until running transactions complete separately from the normal 87 * transaction sequencing. FIXME TODO. 88 */ 89 static int hammer2_strategy_read(struct vop_strategy_args *ap); 90 static int hammer2_strategy_write(struct vop_strategy_args *ap); 91 static void hammer2_strategy_read_completion(hammer2_chain_t *focus, 92 const char *data, struct bio *bio); 93 94 static hammer2_off_t hammer2_dedup_lookup(hammer2_dev_t *hmp, 95 char **datap, int pblksize); 96 97 int 98 hammer2_vop_strategy(struct vop_strategy_args *ap) 99 { 100 struct bio *biop; 101 struct buf *bp; 102 int error; 103 104 biop = ap->a_bio; 105 bp = biop->bio_buf; 106 107 switch(bp->b_cmd) { 108 case BUF_CMD_READ: 109 error = hammer2_strategy_read(ap); 110 ++hammer2_iod_file_read; 111 break; 112 case BUF_CMD_WRITE: 113 error = hammer2_strategy_write(ap); 114 ++hammer2_iod_file_write; 115 break; 116 default: 117 bp->b_error = error = EINVAL; 118 bp->b_flags |= B_ERROR; 119 biodone(biop); 120 break; 121 } 122 return (error); 123 } 124 125 /* 126 * Return the largest contiguous physical disk range for the logical 127 * request, in bytes. 128 * 129 * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb) 130 * 131 * Basically disabled, the logical buffer write thread has to deal with 132 * buffers one-at-a-time. Note that this should not prevent cluster_read() 133 * from reading-ahead, it simply prevents it from trying form a single 134 * cluster buffer for the logical request. H2 already uses 64KB buffers! 135 */ 136 int 137 hammer2_vop_bmap(struct vop_bmap_args *ap) 138 { 139 *ap->a_doffsetp = NOOFFSET; 140 if (ap->a_runp) 141 *ap->a_runp = 0; 142 if (ap->a_runb) 143 *ap->a_runb = 0; 144 return (EOPNOTSUPP); 145 } 146 147 /**************************************************************************** 148 * READ SUPPORT * 149 ****************************************************************************/ 150 /* 151 * Callback used in read path in case that a block is compressed with LZ4. 152 */ 153 static 154 void 155 hammer2_decompress_LZ4_callback(const char *data, u_int bytes, struct bio *bio) 156 { 157 struct buf *bp; 158 char *compressed_buffer; 159 int compressed_size; 160 int result; 161 162 bp = bio->bio_buf; 163 164 #if 0 165 if bio->bio_caller_info2.index && 166 bio->bio_caller_info1.uvalue32 != 167 crc32(bp->b_data, bp->b_bufsize) --- return error 168 #endif 169 170 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 171 compressed_size = *(const int *)data; 172 KKASSERT((uint32_t)compressed_size <= bytes - sizeof(int)); 173 174 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 175 result = LZ4_decompress_safe(__DECONST(char *, &data[sizeof(int)]), 176 compressed_buffer, 177 compressed_size, 178 bp->b_bufsize); 179 if (result < 0) { 180 kprintf("READ PATH: Error during decompression." 181 "bio %016jx/%d\n", 182 (intmax_t)bio->bio_offset, bytes); 183 /* make sure it isn't random garbage */ 184 bzero(compressed_buffer, bp->b_bufsize); 185 } 186 KKASSERT(result <= bp->b_bufsize); 187 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 188 if (result < bp->b_bufsize) 189 bzero(bp->b_data + result, bp->b_bufsize - result); 190 objcache_put(cache_buffer_read, compressed_buffer); 191 bp->b_resid = 0; 192 bp->b_flags |= B_AGE; 193 } 194 195 /* 196 * Callback used in read path in case that a block is compressed with ZLIB. 197 * It is almost identical to LZ4 callback, so in theory they can be unified, 198 * but we didn't want to make changes in bio structure for that. 199 */ 200 static 201 void 202 hammer2_decompress_ZLIB_callback(const char *data, u_int bytes, struct bio *bio) 203 { 204 struct buf *bp; 205 char *compressed_buffer; 206 z_stream strm_decompress; 207 int result; 208 int ret; 209 210 bp = bio->bio_buf; 211 212 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 213 strm_decompress.avail_in = 0; 214 strm_decompress.next_in = Z_NULL; 215 216 ret = inflateInit(&strm_decompress); 217 218 if (ret != Z_OK) 219 kprintf("HAMMER2 ZLIB: Fatal error in inflateInit.\n"); 220 221 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 222 strm_decompress.next_in = __DECONST(char *, data); 223 224 /* XXX supply proper size, subset of device bp */ 225 strm_decompress.avail_in = bytes; 226 strm_decompress.next_out = compressed_buffer; 227 strm_decompress.avail_out = bp->b_bufsize; 228 229 ret = inflate(&strm_decompress, Z_FINISH); 230 if (ret != Z_STREAM_END) { 231 kprintf("HAMMER2 ZLIB: Fatar error during decompression.\n"); 232 bzero(compressed_buffer, bp->b_bufsize); 233 } 234 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 235 result = bp->b_bufsize - strm_decompress.avail_out; 236 if (result < bp->b_bufsize) 237 bzero(bp->b_data + result, strm_decompress.avail_out); 238 objcache_put(cache_buffer_read, compressed_buffer); 239 ret = inflateEnd(&strm_decompress); 240 241 bp->b_resid = 0; 242 bp->b_flags |= B_AGE; 243 } 244 245 /* 246 * Logical buffer I/O, async read. 247 */ 248 static 249 int 250 hammer2_strategy_read(struct vop_strategy_args *ap) 251 { 252 hammer2_xop_strategy_t *xop; 253 struct bio *bio; 254 hammer2_inode_t *ip; 255 hammer2_key_t lbase; 256 257 bio = ap->a_bio; 258 ip = VTOI(ap->a_vp); 259 260 lbase = bio->bio_offset; 261 KKASSERT(((int)lbase & HAMMER2_PBUFMASK) == 0); 262 263 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_STRATEGY); 264 xop->finished = 0; 265 xop->bio = bio; 266 xop->lbase = lbase; 267 hammer2_mtx_init(&xop->lock, "h2bior"); 268 hammer2_xop_start(&xop->head, &hammer2_strategy_read_desc); 269 /* asynchronous completion */ 270 271 return(0); 272 } 273 274 /* 275 * Per-node XOP (threaded), do a synchronous lookup of the chain and 276 * its data. The frontend is asynchronous, so we are also responsible 277 * for racing to terminate the frontend. 278 */ 279 void 280 hammer2_xop_strategy_read(hammer2_xop_t *arg, void *scratch, int clindex) 281 { 282 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 283 hammer2_chain_t *parent; 284 hammer2_chain_t *chain; 285 hammer2_chain_t *focus; 286 hammer2_key_t key_dummy; 287 hammer2_key_t lbase; 288 struct bio *bio; 289 struct buf *bp; 290 const char *data; 291 int error; 292 293 /* 294 * Note that we can race completion of the bio supplied by 295 * the front-end so we cannot access it until we determine 296 * that we are the ones finishing it up. 297 */ 298 lbase = xop->lbase; 299 300 /* 301 * This is difficult to optimize. The logical buffer might be 302 * partially dirty (contain dummy zero-fill pages), which would 303 * mess up our crc calculation if we were to try a direct read. 304 * So for now we always double-buffer through the underlying 305 * storage. 306 * 307 * If not for the above problem we could conditionalize on 308 * (1) 64KB buffer, (2) one chain (not multi-master) and 309 * (3) !hammer2_double_buffer, and issue a direct read into the 310 * logical buffer. 311 */ 312 parent = hammer2_inode_chain(xop->head.ip1, clindex, 313 HAMMER2_RESOLVE_ALWAYS | 314 HAMMER2_RESOLVE_SHARED); 315 if (parent) { 316 chain = hammer2_chain_lookup(&parent, &key_dummy, 317 lbase, lbase, 318 &error, 319 HAMMER2_LOOKUP_ALWAYS | 320 HAMMER2_LOOKUP_SHARED); 321 if (chain) 322 error = chain->error; 323 } else { 324 error = HAMMER2_ERROR_EIO; 325 chain = NULL; 326 } 327 error = hammer2_xop_feed(&xop->head, chain, clindex, error); 328 if (chain) { 329 hammer2_chain_unlock(chain); 330 hammer2_chain_drop(chain); 331 } 332 if (parent) { 333 hammer2_chain_unlock(parent); 334 hammer2_chain_drop(parent); 335 } 336 chain = NULL; /* safety */ 337 parent = NULL; /* safety */ 338 339 /* 340 * Race to finish the frontend. First-to-complete. bio is only 341 * valid if we are determined to be the ones able to complete 342 * the operation. 343 */ 344 if (xop->finished) 345 return; 346 hammer2_mtx_ex(&xop->lock); 347 if (xop->finished) { 348 hammer2_mtx_unlock(&xop->lock); 349 return; 350 } 351 bio = xop->bio; 352 bp = bio->bio_buf; 353 bkvasync(bp); 354 355 /* 356 * Async operation has not completed and we now own the lock. 357 * Determine if we can complete the operation by issuing the 358 * frontend collection non-blocking. 359 * 360 * H2 double-buffers the data, setting B_NOTMETA on the logical 361 * buffer hints to the OS that the logical buffer should not be 362 * swapcached (since the device buffer can be). 363 * 364 * Also note that even for compressed data we would rather the 365 * kernel cache/swapcache device buffers more and (decompressed) 366 * logical buffers less, since that will significantly improve 367 * the amount of end-user data that can be cached. 368 * 369 * NOTE: The chain->data for xop->head.cluster.focus will be 370 * synchronized to the current cpu by xop_collect(), 371 * but other chains in the cluster might not be. 372 */ 373 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 374 375 switch(error) { 376 case 0: 377 xop->finished = 1; 378 hammer2_mtx_unlock(&xop->lock); 379 bp->b_flags |= B_NOTMETA; 380 focus = xop->head.cluster.focus; 381 data = hammer2_xop_gdata(&xop->head)->buf; 382 hammer2_strategy_read_completion(focus, data, xop->bio); 383 hammer2_xop_pdata(&xop->head); 384 biodone(bio); 385 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 386 break; 387 case HAMMER2_ERROR_ENOENT: 388 xop->finished = 1; 389 hammer2_mtx_unlock(&xop->lock); 390 bp->b_flags |= B_NOTMETA; 391 bp->b_resid = 0; 392 bp->b_error = 0; 393 bzero(bp->b_data, bp->b_bcount); 394 biodone(bio); 395 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 396 break; 397 case HAMMER2_ERROR_EINPROGRESS: 398 hammer2_mtx_unlock(&xop->lock); 399 break; 400 default: 401 kprintf("xop_strategy_read: error %08x loff=%016jx\n", 402 error, bp->b_loffset); 403 xop->finished = 1; 404 hammer2_mtx_unlock(&xop->lock); 405 bp->b_flags |= B_ERROR; 406 bp->b_error = EIO; 407 biodone(bio); 408 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 409 break; 410 } 411 } 412 413 static 414 void 415 hammer2_strategy_read_completion(hammer2_chain_t *focus, const char *data, 416 struct bio *bio) 417 { 418 struct buf *bp = bio->bio_buf; 419 420 if (focus->bref.type == HAMMER2_BREF_TYPE_INODE) { 421 /* 422 * Copy from in-memory inode structure. 423 */ 424 bcopy(((const hammer2_inode_data_t *)data)->u.data, 425 bp->b_data, HAMMER2_EMBEDDED_BYTES); 426 bzero(bp->b_data + HAMMER2_EMBEDDED_BYTES, 427 bp->b_bcount - HAMMER2_EMBEDDED_BYTES); 428 bp->b_resid = 0; 429 bp->b_error = 0; 430 } else if (focus->bref.type == HAMMER2_BREF_TYPE_DATA) { 431 /* 432 * Data is on-media, record for live dedup. Release the 433 * chain (try to free it) when done. The data is still 434 * cached by both the buffer cache in front and the 435 * block device behind us. This leaves more room in the 436 * LRU chain cache for meta-data chains which we really 437 * want to retain. 438 * 439 * NOTE: Deduplication cannot be safely recorded for 440 * records without a check code. 441 */ 442 hammer2_dedup_record(focus, NULL, data); 443 atomic_set_int(&focus->flags, HAMMER2_CHAIN_RELEASE); 444 445 /* 446 * Decompression and copy. 447 */ 448 switch (HAMMER2_DEC_COMP(focus->bref.methods)) { 449 case HAMMER2_COMP_LZ4: 450 hammer2_decompress_LZ4_callback(data, focus->bytes, 451 bio); 452 /* b_resid set by call */ 453 break; 454 case HAMMER2_COMP_ZLIB: 455 hammer2_decompress_ZLIB_callback(data, focus->bytes, 456 bio); 457 /* b_resid set by call */ 458 break; 459 case HAMMER2_COMP_NONE: 460 KKASSERT(focus->bytes <= bp->b_bcount); 461 bcopy(data, bp->b_data, focus->bytes); 462 if (focus->bytes < bp->b_bcount) { 463 bzero(bp->b_data + focus->bytes, 464 bp->b_bcount - focus->bytes); 465 } 466 bp->b_resid = 0; 467 bp->b_error = 0; 468 break; 469 default: 470 panic("hammer2_strategy_read_completion: " 471 "unknown compression type"); 472 } 473 } else { 474 panic("hammer2_strategy_read_completion: unknown bref type"); 475 } 476 } 477 478 /**************************************************************************** 479 * WRITE SUPPORT * 480 ****************************************************************************/ 481 482 /* 483 * Functions for compression in threads, 484 * from hammer2_vnops.c 485 */ 486 static void hammer2_write_file_core(char *data, hammer2_inode_t *ip, 487 hammer2_chain_t **parentp, 488 hammer2_key_t lbase, int ioflag, int pblksize, 489 hammer2_tid_t mtid, int *errorp); 490 static void hammer2_compress_and_write(char *data, hammer2_inode_t *ip, 491 hammer2_chain_t **parentp, 492 hammer2_key_t lbase, int ioflag, int pblksize, 493 hammer2_tid_t mtid, int *errorp, 494 int comp_algo, int check_algo); 495 static void hammer2_zero_check_and_write(char *data, hammer2_inode_t *ip, 496 hammer2_chain_t **parentp, 497 hammer2_key_t lbase, int ioflag, int pblksize, 498 hammer2_tid_t mtid, int *errorp, 499 int check_algo); 500 static int test_block_zeros(const char *buf, size_t bytes); 501 static void zero_write(char *data, hammer2_inode_t *ip, 502 hammer2_chain_t **parentp, 503 hammer2_key_t lbase, 504 hammer2_tid_t mtid, int *errorp); 505 static void hammer2_write_bp(hammer2_chain_t *chain, char *data, 506 int ioflag, int pblksize, 507 hammer2_tid_t mtid, int *errorp, 508 int check_algo); 509 510 int 511 hammer2_strategy_write(struct vop_strategy_args *ap) 512 { 513 hammer2_xop_strategy_t *xop; 514 hammer2_pfs_t *pmp; 515 struct bio *bio; 516 hammer2_inode_t *ip; 517 518 bio = ap->a_bio; 519 ip = VTOI(ap->a_vp); 520 pmp = ip->pmp; 521 522 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 523 hammer2_lwinprog_ref(pmp); 524 hammer2_trans_assert_strategy(pmp); 525 hammer2_trans_init(pmp, HAMMER2_TRANS_BUFCACHE); 526 527 xop = hammer2_xop_alloc(ip, HAMMER2_XOP_MODIFYING | 528 HAMMER2_XOP_STRATEGY); 529 xop->finished = 0; 530 xop->bio = bio; 531 xop->lbase = bio->bio_offset; 532 hammer2_mtx_init(&xop->lock, "h2biow"); 533 hammer2_xop_start(&xop->head, &hammer2_strategy_write_desc); 534 /* asynchronous completion */ 535 536 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 537 538 return(0); 539 } 540 541 /* 542 * Per-node XOP (threaded). Write the logical buffer to the media. 543 * 544 * This is a bit problematic because there may be multiple target and 545 * any of them may be able to release the bp. In addition, if our 546 * particulr target is offline we don't want to block the bp (and thus 547 * the frontend). To accomplish this we copy the data to the per-thr 548 * scratch buffer. 549 */ 550 void 551 hammer2_xop_strategy_write(hammer2_xop_t *arg, void *scratch, int clindex) 552 { 553 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 554 hammer2_chain_t *parent; 555 hammer2_key_t lbase; 556 hammer2_inode_t *ip; 557 struct bio *bio; 558 struct buf *bp; 559 int error; 560 int lblksize; 561 int pblksize; 562 hammer2_off_t bio_offset; 563 char *bio_data; 564 565 /* 566 * We can only access the bp/bio if the frontend has not yet 567 * completed. 568 */ 569 if (xop->finished) 570 return; 571 hammer2_mtx_sh(&xop->lock); 572 if (xop->finished) { 573 hammer2_mtx_unlock(&xop->lock); 574 return; 575 } 576 577 lbase = xop->lbase; 578 bio = xop->bio; /* ephermal */ 579 bp = bio->bio_buf; /* ephermal */ 580 ip = xop->head.ip1; /* retained by ref */ 581 bio_offset = bio->bio_offset; 582 bio_data = scratch; 583 584 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 585 586 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 587 pblksize = hammer2_calc_physical(ip, lbase); 588 bkvasync(bp); 589 KKASSERT(lblksize <= MAXPHYS); 590 bcopy(bp->b_data, bio_data, lblksize); 591 592 hammer2_mtx_unlock(&xop->lock); 593 bp = NULL; /* safety, illegal to access after unlock */ 594 bio = NULL; /* safety, illegal to access after unlock */ 595 596 /* 597 * Actual operation 598 */ 599 parent = hammer2_inode_chain(ip, clindex, HAMMER2_RESOLVE_ALWAYS); 600 hammer2_write_file_core(bio_data, ip, &parent, 601 lbase, IO_ASYNC, pblksize, 602 xop->head.mtid, &error); 603 if (parent) { 604 hammer2_chain_unlock(parent); 605 hammer2_chain_drop(parent); 606 parent = NULL; /* safety */ 607 } 608 hammer2_xop_feed(&xop->head, NULL, clindex, error); 609 610 /* 611 * Try to complete the operation on behalf of the front-end. 612 */ 613 if (xop->finished) 614 return; 615 hammer2_mtx_ex(&xop->lock); 616 if (xop->finished) { 617 hammer2_mtx_unlock(&xop->lock); 618 return; 619 } 620 621 /* 622 * Async operation has not completed and we now own the lock. 623 * Determine if we can complete the operation by issuing the 624 * frontend collection non-blocking. 625 * 626 * H2 double-buffers the data, setting B_NOTMETA on the logical 627 * buffer hints to the OS that the logical buffer should not be 628 * swapcached (since the device buffer can be). 629 */ 630 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 631 632 if (error == HAMMER2_ERROR_EINPROGRESS) { 633 hammer2_mtx_unlock(&xop->lock); 634 return; 635 } 636 637 /* 638 * Async operation has completed. 639 */ 640 xop->finished = 1; 641 hammer2_mtx_unlock(&xop->lock); 642 643 bio = xop->bio; /* now owned by us */ 644 bp = bio->bio_buf; /* now owned by us */ 645 646 if (error == HAMMER2_ERROR_ENOENT || error == 0) { 647 bp->b_flags |= B_NOTMETA; 648 bp->b_resid = 0; 649 bp->b_error = 0; 650 biodone(bio); 651 } else { 652 kprintf("xop_strategy_write: error %d loff=%016jx\n", 653 error, bp->b_loffset); 654 bp->b_flags |= B_ERROR; 655 bp->b_error = EIO; 656 biodone(bio); 657 } 658 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 659 hammer2_trans_assert_strategy(ip->pmp); 660 hammer2_lwinprog_drop(ip->pmp); 661 hammer2_trans_done(ip->pmp, HAMMER2_TRANS_BUFCACHE); 662 } 663 664 /* 665 * Wait for pending I/O to complete 666 */ 667 void 668 hammer2_bioq_sync(hammer2_pfs_t *pmp) 669 { 670 hammer2_lwinprog_wait(pmp, 0); 671 } 672 673 /* 674 * Assign physical storage at (cparent, lbase), returning a suitable chain 675 * and setting *errorp appropriately. 676 * 677 * If no error occurs, the returned chain will be in a modified state. 678 * 679 * If an error occurs, the returned chain may or may not be NULL. If 680 * not-null any chain->error (if not 0) will also be rolled up into *errorp. 681 * So the caller only needs to test *errorp. 682 * 683 * cparent can wind up being anything. 684 * 685 * If datap is not NULL, *datap points to the real data we intend to write. 686 * If we can dedup the storage location we set *datap to NULL to indicate 687 * to the caller that a dedup occurred. 688 * 689 * NOTE: Special case for data embedded in inode. 690 */ 691 static 692 hammer2_chain_t * 693 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 694 hammer2_key_t lbase, int pblksize, 695 hammer2_tid_t mtid, char **datap, int *errorp) 696 { 697 hammer2_chain_t *chain; 698 hammer2_key_t key_dummy; 699 hammer2_off_t dedup_off; 700 int pradix = hammer2_getradix(pblksize); 701 702 /* 703 * Locate the chain associated with lbase, return a locked chain. 704 * However, do not instantiate any data reference (which utilizes a 705 * device buffer) because we will be using direct IO via the 706 * logical buffer cache buffer. 707 */ 708 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 709 710 chain = hammer2_chain_lookup(parentp, &key_dummy, 711 lbase, lbase, 712 errorp, 713 HAMMER2_LOOKUP_NODATA); 714 715 /* 716 * The lookup code should not return a DELETED chain to us, unless 717 * its a short-file embedded in the inode. Then it is possible for 718 * the lookup to return a deleted inode. 719 */ 720 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED) && 721 chain->bref.type != HAMMER2_BREF_TYPE_INODE) { 722 kprintf("assign physical deleted chain @ " 723 "%016jx (%016jx.%02x) ip %016jx\n", 724 lbase, chain->bref.data_off, chain->bref.type, 725 ip->meta.inum); 726 Debugger("bleh"); 727 } 728 729 if (chain == NULL) { 730 /* 731 * We found a hole, create a new chain entry. 732 * 733 * NOTE: DATA chains are created without device backing 734 * store (nor do we want any). 735 */ 736 dedup_off = hammer2_dedup_lookup((*parentp)->hmp, datap, 737 pblksize); 738 *errorp |= hammer2_chain_create(parentp, &chain, NULL, ip->pmp, 739 HAMMER2_ENC_CHECK(ip->meta.check_algo) | 740 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE), 741 lbase, HAMMER2_PBUFRADIX, 742 HAMMER2_BREF_TYPE_DATA, 743 pblksize, mtid, 744 dedup_off, 0); 745 if (chain == NULL) 746 goto failed; 747 /*ip->delta_dcount += pblksize;*/ 748 } else if (chain->error == 0) { 749 switch (chain->bref.type) { 750 case HAMMER2_BREF_TYPE_INODE: 751 /* 752 * The data is embedded in the inode, which requires 753 * a bit more finess. 754 */ 755 *errorp |= hammer2_chain_modify_ip(ip, chain, mtid, 0); 756 break; 757 case HAMMER2_BREF_TYPE_DATA: 758 dedup_off = hammer2_dedup_lookup(chain->hmp, datap, 759 pblksize); 760 if (chain->bytes != pblksize) { 761 *errorp |= hammer2_chain_resize(chain, 762 mtid, dedup_off, 763 pradix, 764 HAMMER2_MODIFY_OPTDATA); 765 if (*errorp) 766 break; 767 } 768 769 /* 770 * DATA buffers must be marked modified whether the 771 * data is in a logical buffer or not. We also have 772 * to make this call to fixup the chain data pointers 773 * after resizing in case this is an encrypted or 774 * compressed buffer. 775 */ 776 *errorp |= hammer2_chain_modify(chain, mtid, dedup_off, 777 HAMMER2_MODIFY_OPTDATA); 778 break; 779 default: 780 panic("hammer2_assign_physical: bad type"); 781 /* NOT REACHED */ 782 break; 783 } 784 } else { 785 *errorp = chain->error; 786 } 787 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 788 failed: 789 return (chain); 790 } 791 792 /* 793 * hammer2_write_file_core() - hammer2_write_thread() helper 794 * 795 * The core write function which determines which path to take 796 * depending on compression settings. We also have to locate the 797 * related chains so we can calculate and set the check data for 798 * the blockref. 799 */ 800 static 801 void 802 hammer2_write_file_core(char *data, hammer2_inode_t *ip, 803 hammer2_chain_t **parentp, 804 hammer2_key_t lbase, int ioflag, int pblksize, 805 hammer2_tid_t mtid, int *errorp) 806 { 807 hammer2_chain_t *chain; 808 char *bdata; 809 810 *errorp = 0; 811 812 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 813 case HAMMER2_COMP_NONE: 814 /* 815 * We have to assign physical storage to the buffer 816 * we intend to dirty or write now to avoid deadlocks 817 * in the strategy code later. 818 * 819 * This can return NOOFFSET for inode-embedded data. 820 * The strategy code will take care of it in that case. 821 */ 822 bdata = data; 823 chain = hammer2_assign_physical(ip, parentp, lbase, pblksize, 824 mtid, &bdata, errorp); 825 if (*errorp) { 826 /* skip modifications */ 827 } else if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 828 hammer2_inode_data_t *wipdata; 829 830 wipdata = &chain->data->ipdata; 831 KKASSERT(wipdata->meta.op_flags & 832 HAMMER2_OPFLAG_DIRECTDATA); 833 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 834 ++hammer2_iod_file_wembed; 835 } else if (bdata == NULL) { 836 /* 837 * Copy of data already present on-media. 838 */ 839 chain->bref.methods = 840 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 841 HAMMER2_ENC_CHECK(ip->meta.check_algo); 842 hammer2_chain_setcheck(chain, data); 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, data 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_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 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 } 1211 if (chain) { 1212 hammer2_chain_unlock(chain); 1213 hammer2_chain_drop(chain); 1214 } 1215 } 1216 } 1217 1218 /* 1219 * Helper 1220 * 1221 * A function to test whether a block of data contains only zeros, 1222 * returns TRUE (non-zero) if the block is all zeros. 1223 */ 1224 static 1225 int 1226 test_block_zeros(const char *buf, size_t bytes) 1227 { 1228 size_t i; 1229 1230 for (i = 0; i < bytes; i += sizeof(long)) { 1231 if (*(const long *)(buf + i) != 0) 1232 return (0); 1233 } 1234 return (1); 1235 } 1236 1237 /* 1238 * Helper 1239 * 1240 * Function to "write" a block that contains only zeros. 1241 */ 1242 static 1243 void 1244 zero_write(char *data, hammer2_inode_t *ip, 1245 hammer2_chain_t **parentp, 1246 hammer2_key_t lbase, hammer2_tid_t mtid, int *errorp) 1247 { 1248 hammer2_chain_t *chain; 1249 hammer2_key_t key_dummy; 1250 1251 chain = hammer2_chain_lookup(parentp, &key_dummy, 1252 lbase, lbase, 1253 errorp, 1254 HAMMER2_LOOKUP_NODATA); 1255 if (chain) { 1256 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1257 hammer2_inode_data_t *wipdata; 1258 1259 if (*errorp == 0) { 1260 *errorp = hammer2_chain_modify_ip(ip, chain, 1261 mtid, 0); 1262 } 1263 if (*errorp == 0) { 1264 wipdata = &chain->data->ipdata; 1265 KKASSERT(wipdata->meta.op_flags & 1266 HAMMER2_OPFLAG_DIRECTDATA); 1267 bzero(wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1268 ++hammer2_iod_file_wembed; 1269 } 1270 } else { 1271 /* chain->error ok for deletion */ 1272 hammer2_chain_delete(*parentp, chain, 1273 mtid, HAMMER2_DELETE_PERMANENT); 1274 ++hammer2_iod_file_wzero; 1275 } 1276 atomic_set_int(&ip->flags, HAMMER2_INODE_DIRTYDATA); 1277 hammer2_chain_unlock(chain); 1278 hammer2_chain_drop(chain); 1279 } else { 1280 ++hammer2_iod_file_wzero; 1281 } 1282 } 1283 1284 /* 1285 * Helper 1286 * 1287 * Function to write the data as it is, without performing any sort of 1288 * compression. This function is used in path without compression and 1289 * default zero-checking path. 1290 */ 1291 static 1292 void 1293 hammer2_write_bp(hammer2_chain_t *chain, char *data, int ioflag, 1294 int pblksize, 1295 hammer2_tid_t mtid, int *errorp, int check_algo) 1296 { 1297 hammer2_inode_data_t *wipdata; 1298 hammer2_io_t *dio; 1299 char *bdata; 1300 int error; 1301 1302 error = 0; /* XXX TODO below */ 1303 1304 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1305 1306 switch(chain->bref.type) { 1307 case HAMMER2_BREF_TYPE_INODE: 1308 wipdata = &chain->data->ipdata; 1309 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1310 bcopy(data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1311 error = 0; 1312 ++hammer2_iod_file_wembed; 1313 break; 1314 case HAMMER2_BREF_TYPE_DATA: 1315 error = hammer2_io_newnz(chain->hmp, 1316 chain->bref.type, 1317 chain->bref.data_off, 1318 chain->bytes, &dio); 1319 if (error) { 1320 hammer2_io_bqrelse(&dio); 1321 kprintf("hammer2: WRITE PATH: " 1322 "dbp bread error\n"); 1323 break; 1324 } 1325 bdata = hammer2_io_data(dio, chain->bref.data_off); 1326 1327 chain->bref.methods = HAMMER2_ENC_COMP(HAMMER2_COMP_NONE) + 1328 HAMMER2_ENC_CHECK(check_algo); 1329 bcopy(data, bdata, chain->bytes); 1330 1331 /* 1332 * The flush code doesn't calculate check codes for 1333 * file data (doing so can result in excessive I/O), 1334 * so we do it here. 1335 */ 1336 hammer2_chain_setcheck(chain, bdata); 1337 1338 /* 1339 * Device buffer is now valid, chain is no longer in 1340 * the initial state. 1341 * 1342 * (No blockref table worries with file data) 1343 */ 1344 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1345 hammer2_dedup_record(chain, dio, bdata); 1346 1347 if (ioflag & IO_SYNC) { 1348 /* 1349 * Synchronous I/O requested. 1350 */ 1351 hammer2_io_bwrite(&dio); 1352 /* 1353 } else if ((ioflag & IO_DIRECT) && 1354 loff + n == pblksize) { 1355 hammer2_io_bdwrite(&dio); 1356 */ 1357 } else if (ioflag & IO_ASYNC) { 1358 hammer2_io_bawrite(&dio); 1359 } else { 1360 hammer2_io_bdwrite(&dio); 1361 } 1362 break; 1363 default: 1364 panic("hammer2_write_bp: bad chain type %d\n", 1365 chain->bref.type); 1366 /* NOT REACHED */ 1367 error = 0; 1368 break; 1369 } 1370 *errorp = error; 1371 } 1372 1373 /* 1374 * LIVE DEDUP HEURISTICS 1375 * 1376 * Record media and crc information for possible dedup operation. Note 1377 * that the dedup mask bits must also be set in the related DIO for a dedup 1378 * to be fully validated (which is handled in the freemap allocation code). 1379 * 1380 * WARNING! This code is SMP safe but the heuristic allows SMP collisions. 1381 * All fields must be loaded into locals and validated. 1382 * 1383 * WARNING! Should only be used for file data and directory entries, 1384 * hammer2_chain_modify() only checks for the dedup case on data 1385 * chains. Also, dedup data can only be recorded for committed 1386 * chains (so NOT strategy writes which can undergo further 1387 * modification after the fact!). 1388 */ 1389 void 1390 hammer2_dedup_record(hammer2_chain_t *chain, hammer2_io_t *dio, 1391 const char *data) 1392 { 1393 hammer2_dev_t *hmp; 1394 hammer2_dedup_t *dedup; 1395 uint64_t crc; 1396 uint64_t mask; 1397 int best = 0; 1398 int i; 1399 int dticks; 1400 1401 /* 1402 * We can only record a dedup if we have media data to test against. 1403 * If dedup is not enabled, return early, which allows a chain to 1404 * remain marked MODIFIED (which might have benefits in special 1405 * situations, though typically it does not). 1406 */ 1407 if (hammer2_dedup_enable == 0) 1408 return; 1409 if (dio == NULL) { 1410 dio = chain->dio; 1411 if (dio == NULL) 1412 return; 1413 } 1414 1415 hmp = chain->hmp; 1416 1417 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) { 1418 case HAMMER2_CHECK_ISCSI32: 1419 /* 1420 * XXX use the built-in crc (the dedup lookup sequencing 1421 * needs to be fixed so the check code is already present 1422 * when dedup_lookup is called) 1423 */ 1424 #if 0 1425 crc = (uint64_t)(uint32_t)chain->bref.check.iscsi32.value; 1426 #endif 1427 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1428 break; 1429 case HAMMER2_CHECK_XXHASH64: 1430 crc = chain->bref.check.xxhash64.value; 1431 break; 1432 case HAMMER2_CHECK_SHA192: 1433 /* 1434 * XXX use the built-in crc (the dedup lookup sequencing 1435 * needs to be fixed so the check code is already present 1436 * when dedup_lookup is called) 1437 */ 1438 #if 0 1439 crc = ((uint64_t *)chain->bref.check.sha192.data)[0] ^ 1440 ((uint64_t *)chain->bref.check.sha192.data)[1] ^ 1441 ((uint64_t *)chain->bref.check.sha192.data)[2]; 1442 #endif 1443 crc = XXH64(data, chain->bytes, XXH_HAMMER2_SEED); 1444 break; 1445 default: 1446 /* 1447 * Cannot dedup without a check code 1448 * 1449 * NOTE: In particular, CHECK_NONE allows a sector to be 1450 * overwritten without copy-on-write, recording 1451 * a dedup block for a CHECK_NONE object would be 1452 * a disaster! 1453 */ 1454 return; 1455 } 1456 1457 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DEDUPABLE); 1458 1459 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1460 for (i = 0; i < 4; ++i) { 1461 if (dedup[i].data_crc == crc) { 1462 best = i; 1463 break; 1464 } 1465 dticks = (int)(dedup[i].ticks - dedup[best].ticks); 1466 if (dticks < 0 || dticks > hz * 60 * 30) 1467 best = i; 1468 } 1469 dedup += best; 1470 if (hammer2_debug & 0x40000) { 1471 kprintf("REC %04x %016jx %016jx\n", 1472 (int)(dedup - hmp->heur_dedup), 1473 crc, 1474 chain->bref.data_off); 1475 } 1476 dedup->ticks = ticks; 1477 dedup->data_off = chain->bref.data_off; 1478 dedup->data_crc = crc; 1479 1480 /* 1481 * Set the valid bits for the dedup only after we know the data 1482 * buffer has been updated. The alloc bits were set (and the valid 1483 * bits cleared) when the media was allocated. 1484 * 1485 * This is done in two stages becuase the bulkfree code can race 1486 * the gap between allocation and data population. Both masks must 1487 * be set before a bcmp/dedup operation is able to use the block. 1488 */ 1489 mask = hammer2_dedup_mask(dio, chain->bref.data_off, chain->bytes); 1490 atomic_set_64(&dio->dedup_valid, mask); 1491 1492 #if 0 1493 /* 1494 * XXX removed. MODIFIED is an integral part of the flush code, 1495 * lets not just clear it 1496 */ 1497 /* 1498 * Once we record the dedup the chain must be marked clean to 1499 * prevent reuse of the underlying block. Remember that this 1500 * write occurs when the buffer cache is flushed (i.e. on sync(), 1501 * fsync(), filesystem periodic sync, or when the kernel needs to 1502 * flush a buffer), and not whenever the user write()s. 1503 */ 1504 if (chain->flags & HAMMER2_CHAIN_MODIFIED) { 1505 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED); 1506 atomic_add_long(&hammer2_count_modified_chains, -1); 1507 if (chain->pmp) 1508 hammer2_pfs_memory_wakeup(chain->pmp, -1); 1509 } 1510 #endif 1511 } 1512 1513 static 1514 hammer2_off_t 1515 hammer2_dedup_lookup(hammer2_dev_t *hmp, char **datap, int pblksize) 1516 { 1517 hammer2_dedup_t *dedup; 1518 hammer2_io_t *dio; 1519 hammer2_off_t off; 1520 uint64_t crc; 1521 uint64_t mask; 1522 char *data; 1523 char *dtmp; 1524 int i; 1525 1526 if (hammer2_dedup_enable == 0) 1527 return 0; 1528 data = *datap; 1529 if (data == NULL) 1530 return 0; 1531 1532 /* 1533 * XXX use the built-in crc (the dedup lookup sequencing 1534 * needs to be fixed so the check code is already present 1535 * when dedup_lookup is called) 1536 */ 1537 crc = XXH64(data, pblksize, XXH_HAMMER2_SEED); 1538 dedup = &hmp->heur_dedup[crc & (HAMMER2_DEDUP_HEUR_MASK & ~3)]; 1539 1540 if (hammer2_debug & 0x40000) { 1541 kprintf("LOC %04x/4 %016jx\n", 1542 (int)(dedup - hmp->heur_dedup), 1543 crc); 1544 } 1545 1546 for (i = 0; i < 4; ++i) { 1547 off = dedup[i].data_off; 1548 cpu_ccfence(); 1549 if (dedup[i].data_crc != crc) 1550 continue; 1551 if ((1 << (int)(off & HAMMER2_OFF_MASK_RADIX)) != pblksize) 1552 continue; 1553 dio = hammer2_io_getquick(hmp, off, pblksize); 1554 if (dio) { 1555 dtmp = hammer2_io_data(dio, off), 1556 mask = hammer2_dedup_mask(dio, off, pblksize); 1557 if ((dio->dedup_alloc & mask) == mask && 1558 (dio->dedup_valid & mask) == mask && 1559 bcmp(data, dtmp, pblksize) == 0) { 1560 if (hammer2_debug & 0x40000) { 1561 kprintf("DEDUP SUCCESS %016jx\n", 1562 (intmax_t)off); 1563 } 1564 hammer2_io_putblk(&dio); 1565 *datap = NULL; 1566 dedup[i].ticks = ticks; /* update use */ 1567 atomic_add_long(&hammer2_iod_file_wdedup, 1568 pblksize); 1569 1570 return off; /* RETURN */ 1571 } 1572 hammer2_io_putblk(&dio); 1573 } 1574 } 1575 return 0; 1576 } 1577 1578 /* 1579 * Poof. Races are ok, if someone gets in and reuses a dedup offset 1580 * before or while we are clearing it they will also recover the freemap 1581 * entry (set it to fully allocated), so a bulkfree race can only set it 1582 * to a possibly-free state. 1583 * 1584 * XXX ok, well, not really sure races are ok but going to run with it 1585 * for the moment. 1586 */ 1587 void 1588 hammer2_dedup_clear(hammer2_dev_t *hmp) 1589 { 1590 int i; 1591 1592 for (i = 0; i < HAMMER2_DEDUP_HEUR_SIZE; ++i) { 1593 hmp->heur_dedup[i].data_off = 0; 1594 hmp->heur_dedup[i].ticks = ticks - 1; 1595 } 1596 } 1597