1 /* 2 * Copyright (c) 2011-2015 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@dragonflybsd.org> 6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org> 7 * by Daniel Flores (GSOC 2013 - mentored by Matthew Dillon, compression) 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 3. Neither the name of The DragonFly Project nor the names of its 20 * contributors may be used to endorse or promote products derived 21 * from this software without specific, prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 /* 37 * This module handles low level logical file I/O (strategy) which backs 38 * the logical buffer cache. 39 */ 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/fcntl.h> 45 #include <sys/buf.h> 46 #include <sys/proc.h> 47 #include <sys/namei.h> 48 #include <sys/mount.h> 49 #include <sys/vnode.h> 50 #include <sys/mountctl.h> 51 #include <sys/dirent.h> 52 #include <sys/uio.h> 53 #include <sys/objcache.h> 54 #include <sys/event.h> 55 #include <sys/file.h> 56 #include <vfs/fifofs/fifo.h> 57 58 #include "hammer2.h" 59 #include "hammer2_lz4.h" 60 61 #include "zlib/hammer2_zlib.h" 62 63 struct objcache *cache_buffer_read; 64 struct objcache *cache_buffer_write; 65 66 /* 67 * Strategy code (async logical file buffer I/O from system) 68 * 69 * WARNING: The strategy code cannot safely use hammer2 transactions 70 * as this can deadlock against vfs_sync's vfsync() call 71 * if multiple flushes are queued. All H2 structures must 72 * already be present and ready for the DIO. 73 * 74 * Reads can be initiated asynchronously, writes have to be 75 * spooled to a separate thread for action to avoid deadlocks. 76 */ 77 static void hammer2_strategy_xop_read(hammer2_xop_t *arg, int clindex); 78 static void hammer2_strategy_xop_write(hammer2_xop_t *arg, int clindex); 79 static int hammer2_strategy_read(struct vop_strategy_args *ap); 80 static int hammer2_strategy_write(struct vop_strategy_args *ap); 81 static void hammer2_strategy_read_completion(hammer2_chain_t *chain, 82 char *data, struct bio *bio); 83 84 int 85 hammer2_vop_strategy(struct vop_strategy_args *ap) 86 { 87 struct bio *biop; 88 struct buf *bp; 89 int error; 90 91 biop = ap->a_bio; 92 bp = biop->bio_buf; 93 94 switch(bp->b_cmd) { 95 case BUF_CMD_READ: 96 error = hammer2_strategy_read(ap); 97 ++hammer2_iod_file_read; 98 break; 99 case BUF_CMD_WRITE: 100 error = hammer2_strategy_write(ap); 101 ++hammer2_iod_file_write; 102 break; 103 default: 104 bp->b_error = error = EINVAL; 105 bp->b_flags |= B_ERROR; 106 biodone(biop); 107 break; 108 } 109 return (error); 110 } 111 112 /* 113 * Return the largest contiguous physical disk range for the logical 114 * request, in bytes. 115 * 116 * (struct vnode *vp, off_t loffset, off_t *doffsetp, int *runp, int *runb) 117 * 118 * Basically disabled, the logical buffer write thread has to deal with 119 * buffers one-at-a-time. 120 */ 121 int 122 hammer2_vop_bmap(struct vop_bmap_args *ap) 123 { 124 *ap->a_doffsetp = NOOFFSET; 125 if (ap->a_runp) 126 *ap->a_runp = 0; 127 if (ap->a_runb) 128 *ap->a_runb = 0; 129 return (EOPNOTSUPP); 130 } 131 132 /**************************************************************************** 133 * READ SUPPORT * 134 ****************************************************************************/ 135 /* 136 * Callback used in read path in case that a block is compressed with LZ4. 137 */ 138 static 139 void 140 hammer2_decompress_LZ4_callback(const char *data, u_int bytes, struct bio *bio) 141 { 142 struct buf *bp; 143 char *compressed_buffer; 144 int compressed_size; 145 int result; 146 147 bp = bio->bio_buf; 148 149 #if 0 150 if bio->bio_caller_info2.index && 151 bio->bio_caller_info1.uvalue32 != 152 crc32(bp->b_data, bp->b_bufsize) --- return error 153 #endif 154 155 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 156 compressed_size = *(const int *)data; 157 KKASSERT(compressed_size <= bytes - sizeof(int)); 158 159 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 160 result = LZ4_decompress_safe(__DECONST(char *, &data[sizeof(int)]), 161 compressed_buffer, 162 compressed_size, 163 bp->b_bufsize); 164 if (result < 0) { 165 kprintf("READ PATH: Error during decompression." 166 "bio %016jx/%d\n", 167 (intmax_t)bio->bio_offset, bytes); 168 /* make sure it isn't random garbage */ 169 bzero(compressed_buffer, bp->b_bufsize); 170 } 171 KKASSERT(result <= bp->b_bufsize); 172 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 173 if (result < bp->b_bufsize) 174 bzero(bp->b_data + result, bp->b_bufsize - result); 175 objcache_put(cache_buffer_read, compressed_buffer); 176 bp->b_resid = 0; 177 bp->b_flags |= B_AGE; 178 } 179 180 /* 181 * Callback used in read path in case that a block is compressed with ZLIB. 182 * It is almost identical to LZ4 callback, so in theory they can be unified, 183 * but we didn't want to make changes in bio structure for that. 184 */ 185 static 186 void 187 hammer2_decompress_ZLIB_callback(const char *data, u_int bytes, struct bio *bio) 188 { 189 struct buf *bp; 190 char *compressed_buffer; 191 z_stream strm_decompress; 192 int result; 193 int ret; 194 195 bp = bio->bio_buf; 196 197 KKASSERT(bp->b_bufsize <= HAMMER2_PBUFSIZE); 198 strm_decompress.avail_in = 0; 199 strm_decompress.next_in = Z_NULL; 200 201 ret = inflateInit(&strm_decompress); 202 203 if (ret != Z_OK) 204 kprintf("HAMMER2 ZLIB: Fatal error in inflateInit.\n"); 205 206 compressed_buffer = objcache_get(cache_buffer_read, M_INTWAIT); 207 strm_decompress.next_in = __DECONST(char *, data); 208 209 /* XXX supply proper size, subset of device bp */ 210 strm_decompress.avail_in = bytes; 211 strm_decompress.next_out = compressed_buffer; 212 strm_decompress.avail_out = bp->b_bufsize; 213 214 ret = inflate(&strm_decompress, Z_FINISH); 215 if (ret != Z_STREAM_END) { 216 kprintf("HAMMER2 ZLIB: Fatar error during decompression.\n"); 217 bzero(compressed_buffer, bp->b_bufsize); 218 } 219 bcopy(compressed_buffer, bp->b_data, bp->b_bufsize); 220 result = bp->b_bufsize - strm_decompress.avail_out; 221 if (result < bp->b_bufsize) 222 bzero(bp->b_data + result, strm_decompress.avail_out); 223 objcache_put(cache_buffer_read, compressed_buffer); 224 ret = inflateEnd(&strm_decompress); 225 226 bp->b_resid = 0; 227 bp->b_flags |= B_AGE; 228 } 229 230 /* 231 * Logical buffer I/O, async read. 232 */ 233 static 234 int 235 hammer2_strategy_read(struct vop_strategy_args *ap) 236 { 237 hammer2_xop_strategy_t *xop; 238 struct buf *bp; 239 struct bio *bio; 240 struct bio *nbio; 241 hammer2_inode_t *ip; 242 hammer2_key_t lbase; 243 244 bio = ap->a_bio; 245 bp = bio->bio_buf; 246 ip = VTOI(ap->a_vp); 247 nbio = push_bio(bio); 248 249 lbase = bio->bio_offset; 250 KKASSERT(((int)lbase & HAMMER2_PBUFMASK) == 0); 251 252 xop = &hammer2_xop_alloc(ip)->xop_strategy; 253 xop->finished = 0; 254 xop->bio = bio; 255 xop->lbase = lbase; 256 hammer2_xop_start(&xop->head, hammer2_strategy_xop_read); 257 258 return(0); 259 } 260 261 /* 262 * Per-node XOP (threaded), do a synchronous lookup of the chain and 263 * its data. The frontend is asynchronous, so we are also responsible 264 * for racing to terminate the frontend. 265 */ 266 static 267 void 268 hammer2_strategy_xop_read(hammer2_xop_t *arg, int clindex) 269 { 270 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 271 hammer2_chain_t *parent; 272 hammer2_chain_t *chain; 273 hammer2_key_t key_dummy; 274 hammer2_key_t lbase; 275 struct bio *bio; 276 struct buf *bp; 277 int cache_index = -1; 278 int error; 279 280 lbase = xop->lbase; 281 bio = xop->bio; 282 bp = bio->bio_buf; 283 284 parent = hammer2_inode_chain(xop->head.ip, clindex, 285 HAMMER2_RESOLVE_ALWAYS | 286 HAMMER2_RESOLVE_SHARED); 287 if (parent) { 288 chain = hammer2_chain_lookup(&parent, &key_dummy, 289 lbase, lbase, 290 &cache_index, 291 HAMMER2_LOOKUP_ALWAYS | 292 HAMMER2_LOOKUP_SHARED); 293 error = chain ? chain->error : 0; 294 } else { 295 error = EIO; 296 chain = NULL; 297 } 298 error = hammer2_xop_feed(&xop->head, chain, clindex, error); 299 if (chain) 300 hammer2_chain_drop(chain); 301 if (parent) { 302 hammer2_chain_unlock(parent); 303 hammer2_chain_drop(parent); 304 } 305 chain = NULL; /* safety */ 306 parent = NULL; /* safety */ 307 308 /* 309 * Race to finish the frontend 310 */ 311 if (xop->finished) 312 return; 313 hammer2_mtx_ex(&xop->head.xgrp->mtx2); 314 if (xop->finished) { 315 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 316 return; 317 } 318 319 /* 320 * Async operation has not completed and we now own the lock. 321 * Determine if we can complete the operation by issuing the 322 * frontend collection non-blocking. 323 */ 324 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 325 326 switch(error) { 327 case 0: 328 xop->finished = 1; 329 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 330 chain = xop->head.cluster.focus; 331 hammer2_strategy_read_completion(chain, (char *)chain->data, 332 xop->bio); 333 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 334 biodone(bio); 335 break; 336 case ENOENT: 337 xop->finished = 1; 338 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 339 bp->b_resid = 0; 340 bp->b_error = 0; 341 bzero(bp->b_data, bp->b_bcount); 342 biodone(bio); 343 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 344 break; 345 case EINPROGRESS: 346 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 347 break; 348 default: 349 xop->finished = 1; 350 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 351 bp->b_flags |= B_ERROR; 352 bp->b_error = EIO; 353 biodone(bio); 354 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 355 break; 356 } 357 } 358 359 static 360 void 361 hammer2_strategy_read_completion(hammer2_chain_t *chain, char *data, 362 struct bio *bio) 363 { 364 struct buf *bp = bio->bio_buf; 365 366 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 367 /* 368 * Data is embedded in the inode (copy from inode). 369 */ 370 bcopy(((hammer2_inode_data_t *)data)->u.data, 371 bp->b_data, HAMMER2_EMBEDDED_BYTES); 372 bzero(bp->b_data + HAMMER2_EMBEDDED_BYTES, 373 bp->b_bcount - HAMMER2_EMBEDDED_BYTES); 374 bp->b_resid = 0; 375 bp->b_error = 0; 376 } else if (chain->bref.type == HAMMER2_BREF_TYPE_DATA) { 377 /* 378 * Data is on-media, issue device I/O and copy. 379 * 380 * XXX direct-IO shortcut could go here XXX. 381 */ 382 switch (HAMMER2_DEC_COMP(chain->bref.methods)) { 383 case HAMMER2_COMP_LZ4: 384 hammer2_decompress_LZ4_callback(data, chain->bytes, 385 bio); 386 break; 387 case HAMMER2_COMP_ZLIB: 388 hammer2_decompress_ZLIB_callback(data, chain->bytes, 389 bio); 390 break; 391 case HAMMER2_COMP_NONE: 392 KKASSERT(chain->bytes <= bp->b_bcount); 393 bcopy(data, bp->b_data, chain->bytes); 394 if (chain->bytes < bp->b_bcount) { 395 bzero(bp->b_data + chain->bytes, 396 bp->b_bcount - chain->bytes); 397 } 398 bp->b_flags |= B_NOTMETA; 399 bp->b_resid = 0; 400 bp->b_error = 0; 401 break; 402 default: 403 panic("hammer2_strategy_read: " 404 "unknown compression type"); 405 } 406 } else { 407 panic("hammer2_strategy_read: unknown bref type"); 408 } 409 } 410 411 /**************************************************************************** 412 * WRITE SUPPORT * 413 ****************************************************************************/ 414 415 /* 416 * Functions for compression in threads, 417 * from hammer2_vnops.c 418 */ 419 static void hammer2_write_file_core(struct buf *bp, hammer2_inode_t *ip, 420 hammer2_chain_t **parentp, 421 hammer2_key_t lbase, int ioflag, int pblksize, 422 int *errorp); 423 static void hammer2_compress_and_write(struct buf *bp, hammer2_inode_t *ip, 424 hammer2_chain_t **parentp, 425 hammer2_key_t lbase, int ioflag, 426 int pblksize, int *errorp, 427 int comp_algo, int check_algo); 428 static void hammer2_zero_check_and_write(struct buf *bp, hammer2_inode_t *ip, 429 hammer2_chain_t **parentp, 430 hammer2_key_t lbase, 431 int ioflag, int pblksize, int *errorp, 432 int check_algo); 433 static int test_block_zeros(const char *buf, size_t bytes); 434 static void zero_write(struct buf *bp, hammer2_inode_t *ip, 435 hammer2_chain_t **parentp, 436 hammer2_key_t lbase, 437 int *errorp); 438 static void hammer2_write_bp(hammer2_chain_t *chain, struct buf *bp, 439 int ioflag, int pblksize, int *errorp, 440 int check_algo); 441 442 static 443 int 444 hammer2_strategy_write(struct vop_strategy_args *ap) 445 { 446 hammer2_xop_strategy_t *xop; 447 hammer2_pfs_t *pmp; 448 struct bio *bio; 449 struct buf *bp; 450 hammer2_inode_t *ip; 451 452 bio = ap->a_bio; 453 bp = bio->bio_buf; 454 ip = VTOI(ap->a_vp); 455 pmp = ip->pmp; 456 457 hammer2_lwinprog_ref(pmp); 458 hammer2_trans_assert_strategy(pmp); 459 460 xop = &hammer2_xop_alloc(ip)->xop_strategy; 461 xop->finished = 0; 462 xop->bio = bio; 463 xop->lbase = bio->bio_offset; 464 hammer2_xop_start(&xop->head, hammer2_strategy_xop_write); 465 /* asynchronous completion */ 466 467 hammer2_lwinprog_wait(pmp, hammer2_flush_pipe); 468 469 return(0); 470 } 471 472 /* 473 * Per-node XOP (threaded). Write the logical buffer to the media. 474 */ 475 static 476 void 477 hammer2_strategy_xop_write(hammer2_xop_t *arg, int clindex) 478 { 479 hammer2_xop_strategy_t *xop = &arg->xop_strategy; 480 hammer2_chain_t *parent; 481 hammer2_key_t lbase; 482 hammer2_inode_t *ip; 483 struct bio *bio; 484 struct buf *bp; 485 int error; 486 int lblksize; 487 int pblksize; 488 489 lbase = xop->lbase; 490 bio = xop->bio; 491 bp = bio->bio_buf; 492 ip = xop->head.ip; 493 494 /* hammer2_trans_init(parent->hmp->spmp, HAMMER2_TRANS_BUFCACHE); */ 495 496 lblksize = hammer2_calc_logical(ip, bio->bio_offset, &lbase, NULL); 497 pblksize = hammer2_calc_physical(ip, lbase); 498 parent = hammer2_inode_chain(ip, clindex, HAMMER2_RESOLVE_ALWAYS); 499 hammer2_write_file_core(bp, ip, &parent, 500 lbase, IO_ASYNC, 501 pblksize, &error); 502 if (parent) { 503 hammer2_chain_unlock(parent); 504 hammer2_chain_drop(parent); 505 parent = NULL; /* safety */ 506 } 507 error = hammer2_xop_feed(&xop->head, NULL, clindex, error); 508 509 /* 510 * Race to finish the frontend 511 */ 512 if (xop->finished) 513 return; 514 hammer2_mtx_ex(&xop->head.xgrp->mtx2); 515 if (xop->finished) { 516 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 517 return; 518 } 519 520 /* 521 * Async operation has not completed and we now own the lock. 522 * Determine if we can complete the operation by issuing the 523 * frontend collection non-blocking. 524 */ 525 error = hammer2_xop_collect(&xop->head, HAMMER2_XOP_COLLECT_NOWAIT); 526 527 switch(error) { 528 case ENOENT: 529 case 0: 530 xop->finished = 1; 531 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 532 bp->b_resid = 0; 533 bp->b_error = 0; 534 biodone(bio); 535 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 536 hammer2_lwinprog_drop(ip->pmp); 537 break; 538 case EINPROGRESS: 539 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 540 break; 541 default: 542 xop->finished = 1; 543 hammer2_mtx_unlock(&xop->head.xgrp->mtx2); 544 bp->b_flags |= B_ERROR; 545 bp->b_error = EIO; 546 biodone(bio); 547 hammer2_xop_retire(&xop->head, HAMMER2_XOPMASK_VOP); 548 hammer2_lwinprog_drop(ip->pmp); 549 break; 550 } 551 } 552 553 /* 554 * Wait for pending I/O to complete 555 */ 556 void 557 hammer2_bioq_sync(hammer2_pfs_t *pmp) 558 { 559 hammer2_lwinprog_wait(pmp, 0); 560 } 561 562 /* 563 * Create a new cluster at (cparent, lbase) and assign physical storage, 564 * returning a cluster suitable for I/O. The cluster will be in a modified 565 * state. 566 * 567 * cparent can wind up being anything. 568 * 569 * NOTE: Special case for data embedded in inode. 570 */ 571 static 572 hammer2_chain_t * 573 hammer2_assign_physical(hammer2_inode_t *ip, hammer2_chain_t **parentp, 574 hammer2_key_t lbase, int pblksize, int *errorp) 575 { 576 hammer2_chain_t *chain; 577 hammer2_key_t key_dummy; 578 int pradix = hammer2_getradix(pblksize); 579 int cache_index = -1; 580 581 /* 582 * Locate the chain associated with lbase, return a locked chain. 583 * However, do not instantiate any data reference (which utilizes a 584 * device buffer) because we will be using direct IO via the 585 * logical buffer cache buffer. 586 */ 587 *errorp = 0; 588 KKASSERT(pblksize >= HAMMER2_ALLOC_MIN); 589 retry: 590 chain = hammer2_chain_lookup(parentp, &key_dummy, 591 lbase, lbase, 592 &cache_index, 593 HAMMER2_LOOKUP_NODATA); 594 if (chain == NULL) { 595 /* 596 * We found a hole, create a new chain entry. 597 * 598 * NOTE: DATA chains are created without device backing 599 * store (nor do we want any). 600 */ 601 *errorp = hammer2_chain_create(parentp, &chain, ip->pmp, 602 lbase, HAMMER2_PBUFRADIX, 603 HAMMER2_BREF_TYPE_DATA, 604 pblksize, 0); 605 if (chain == NULL) { 606 panic("hammer2_chain_create: par=%p error=%d\n", 607 *parentp, *errorp); 608 goto retry; 609 } 610 /*ip->delta_dcount += pblksize;*/ 611 } else { 612 switch (chain->bref.type) { 613 case HAMMER2_BREF_TYPE_INODE: 614 /* 615 * The data is embedded in the inode, which requires 616 * a bit more finess. 617 */ 618 hammer2_chain_modify_ip(ip, chain, 0); 619 break; 620 case HAMMER2_BREF_TYPE_DATA: 621 if (chain->bytes != pblksize) { 622 hammer2_chain_resize(ip, *parentp, chain, 623 pradix, 624 HAMMER2_MODIFY_OPTDATA); 625 } 626 627 /* 628 * DATA buffers must be marked modified whether the 629 * data is in a logical buffer or not. We also have 630 * to make this call to fixup the chain data pointers 631 * after resizing in case this is an encrypted or 632 * compressed buffer. 633 */ 634 hammer2_chain_modify(chain, HAMMER2_MODIFY_OPTDATA); 635 break; 636 default: 637 panic("hammer2_assign_physical: bad type"); 638 /* NOT REACHED */ 639 break; 640 } 641 } 642 return (chain); 643 } 644 645 /* 646 * hammer2_write_file_core() - hammer2_write_thread() helper 647 * 648 * The core write function which determines which path to take 649 * depending on compression settings. We also have to locate the 650 * related chains so we can calculate and set the check data for 651 * the blockref. 652 */ 653 static 654 void 655 hammer2_write_file_core(struct buf *bp, hammer2_inode_t *ip, 656 hammer2_chain_t **parentp, 657 hammer2_key_t lbase, int ioflag, int pblksize, 658 int *errorp) 659 { 660 hammer2_chain_t *chain; 661 662 switch(HAMMER2_DEC_ALGO(ip->meta.comp_algo)) { 663 case HAMMER2_COMP_NONE: 664 /* 665 * We have to assign physical storage to the buffer 666 * we intend to dirty or write now to avoid deadlocks 667 * in the strategy code later. 668 * 669 * This can return NOOFFSET for inode-embedded data. 670 * The strategy code will take care of it in that case. 671 */ 672 chain = hammer2_assign_physical(ip, parentp, 673 lbase, pblksize, errorp); 674 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 675 hammer2_inode_data_t *wipdata; 676 677 wipdata = &chain->data->ipdata; 678 KKASSERT(wipdata->meta.op_flags & 679 HAMMER2_OPFLAG_DIRECTDATA); 680 KKASSERT(bp->b_loffset == 0); 681 bcopy(bp->b_data, wipdata->u.data, 682 HAMMER2_EMBEDDED_BYTES); 683 } else { 684 hammer2_write_bp(chain, bp, ioflag, pblksize, 685 errorp, ip->meta.check_algo); 686 } 687 if (chain) { 688 hammer2_chain_unlock(chain); 689 hammer2_chain_drop(chain); 690 } 691 break; 692 case HAMMER2_COMP_AUTOZERO: 693 /* 694 * Check for zero-fill only 695 */ 696 hammer2_zero_check_and_write(bp, ip, parentp, 697 lbase, ioflag, 698 pblksize, errorp, 699 ip->meta.check_algo); 700 break; 701 case HAMMER2_COMP_LZ4: 702 case HAMMER2_COMP_ZLIB: 703 default: 704 /* 705 * Check for zero-fill and attempt compression. 706 */ 707 hammer2_compress_and_write(bp, ip, parentp, 708 lbase, ioflag, 709 pblksize, errorp, 710 ip->meta.comp_algo, 711 ip->meta.check_algo); 712 break; 713 } 714 } 715 716 /* 717 * Helper 718 * 719 * Generic function that will perform the compression in compression 720 * write path. The compression algorithm is determined by the settings 721 * obtained from inode. 722 */ 723 static 724 void 725 hammer2_compress_and_write(struct buf *bp, hammer2_inode_t *ip, 726 hammer2_chain_t **parentp, 727 hammer2_key_t lbase, int ioflag, int pblksize, 728 int *errorp, int comp_algo, int check_algo) 729 { 730 hammer2_chain_t *chain; 731 int comp_size; 732 int comp_block_size; 733 char *comp_buffer; 734 735 if (test_block_zeros(bp->b_data, pblksize)) { 736 zero_write(bp, ip, parentp, lbase, errorp); 737 return; 738 } 739 740 comp_size = 0; 741 comp_buffer = NULL; 742 743 KKASSERT(pblksize / 2 <= 32768); 744 745 if (ip->comp_heuristic < 8 || (ip->comp_heuristic & 7) == 0) { 746 z_stream strm_compress; 747 int comp_level; 748 int ret; 749 750 switch(HAMMER2_DEC_ALGO(comp_algo)) { 751 case HAMMER2_COMP_LZ4: 752 comp_buffer = objcache_get(cache_buffer_write, 753 M_INTWAIT); 754 comp_size = LZ4_compress_limitedOutput( 755 bp->b_data, 756 &comp_buffer[sizeof(int)], 757 pblksize, 758 pblksize / 2 - sizeof(int)); 759 /* 760 * We need to prefix with the size, LZ4 761 * doesn't do it for us. Add the related 762 * overhead. 763 */ 764 *(int *)comp_buffer = comp_size; 765 if (comp_size) 766 comp_size += sizeof(int); 767 break; 768 case HAMMER2_COMP_ZLIB: 769 comp_level = HAMMER2_DEC_LEVEL(comp_algo); 770 if (comp_level == 0) 771 comp_level = 6; /* default zlib compression */ 772 else if (comp_level < 6) 773 comp_level = 6; 774 else if (comp_level > 9) 775 comp_level = 9; 776 ret = deflateInit(&strm_compress, comp_level); 777 if (ret != Z_OK) { 778 kprintf("HAMMER2 ZLIB: fatal error " 779 "on deflateInit.\n"); 780 } 781 782 comp_buffer = objcache_get(cache_buffer_write, 783 M_INTWAIT); 784 strm_compress.next_in = bp->b_data; 785 strm_compress.avail_in = pblksize; 786 strm_compress.next_out = comp_buffer; 787 strm_compress.avail_out = pblksize / 2; 788 ret = deflate(&strm_compress, Z_FINISH); 789 if (ret == Z_STREAM_END) { 790 comp_size = pblksize / 2 - 791 strm_compress.avail_out; 792 } else { 793 comp_size = 0; 794 } 795 ret = deflateEnd(&strm_compress); 796 break; 797 default: 798 kprintf("Error: Unknown compression method.\n"); 799 kprintf("Comp_method = %d.\n", comp_algo); 800 break; 801 } 802 } 803 804 if (comp_size == 0) { 805 /* 806 * compression failed or turned off 807 */ 808 comp_block_size = pblksize; /* safety */ 809 if (++ip->comp_heuristic > 128) 810 ip->comp_heuristic = 8; 811 } else { 812 /* 813 * compression succeeded 814 */ 815 ip->comp_heuristic = 0; 816 if (comp_size <= 1024) { 817 comp_block_size = 1024; 818 } else if (comp_size <= 2048) { 819 comp_block_size = 2048; 820 } else if (comp_size <= 4096) { 821 comp_block_size = 4096; 822 } else if (comp_size <= 8192) { 823 comp_block_size = 8192; 824 } else if (comp_size <= 16384) { 825 comp_block_size = 16384; 826 } else if (comp_size <= 32768) { 827 comp_block_size = 32768; 828 } else { 829 panic("hammer2: WRITE PATH: " 830 "Weird comp_size value."); 831 /* NOT REACHED */ 832 comp_block_size = pblksize; 833 } 834 } 835 836 chain = hammer2_assign_physical(ip, parentp, lbase, 837 comp_block_size, errorp); 838 if (*errorp) { 839 kprintf("WRITE PATH: An error occurred while " 840 "assigning physical space.\n"); 841 KKASSERT(chain == NULL); 842 goto done; 843 } 844 845 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 846 hammer2_inode_data_t *wipdata; 847 848 hammer2_chain_modify_ip(ip, chain, 0); 849 wipdata = &chain->data->ipdata; 850 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 851 KKASSERT(bp->b_loffset == 0); 852 bcopy(bp->b_data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 853 } else { 854 hammer2_io_t *dio; 855 char *bdata; 856 857 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 858 859 switch(chain->bref.type) { 860 case HAMMER2_BREF_TYPE_INODE: 861 panic("hammer2_write_bp: unexpected inode\n"); 862 break; 863 case HAMMER2_BREF_TYPE_DATA: 864 /* 865 * Optimize out the read-before-write 866 * if possible. 867 */ 868 *errorp = hammer2_io_newnz(chain->hmp, 869 chain->bref.data_off, 870 chain->bytes, 871 &dio); 872 if (*errorp) { 873 hammer2_io_brelse(&dio); 874 kprintf("hammer2: WRITE PATH: " 875 "dbp bread error\n"); 876 break; 877 } 878 bdata = hammer2_io_data(dio, chain->bref.data_off); 879 880 /* 881 * When loading the block make sure we don't 882 * leave garbage after the compressed data. 883 */ 884 if (comp_size) { 885 chain->bref.methods = 886 HAMMER2_ENC_COMP(comp_algo) + 887 HAMMER2_ENC_CHECK(check_algo); 888 bcopy(comp_buffer, bdata, comp_size); 889 if (comp_size != comp_block_size) { 890 bzero(bdata + comp_size, 891 comp_block_size - comp_size); 892 } 893 } else { 894 chain->bref.methods = 895 HAMMER2_ENC_COMP( 896 HAMMER2_COMP_NONE) + 897 HAMMER2_ENC_CHECK(check_algo); 898 bcopy(bp->b_data, bdata, pblksize); 899 } 900 901 /* 902 * The flush code doesn't calculate check codes for 903 * file data (doing so can result in excessive I/O), 904 * so we do it here. 905 */ 906 hammer2_chain_setcheck(chain, bdata); 907 908 /* 909 * Device buffer is now valid, chain is no longer in 910 * the initial state. 911 * 912 * (No blockref table worries with file data) 913 */ 914 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 915 916 /* Now write the related bdp. */ 917 if (ioflag & IO_SYNC) { 918 /* 919 * Synchronous I/O requested. 920 */ 921 hammer2_io_bwrite(&dio); 922 /* 923 } else if ((ioflag & IO_DIRECT) && 924 loff + n == pblksize) { 925 hammer2_io_bdwrite(&dio); 926 */ 927 } else if (ioflag & IO_ASYNC) { 928 hammer2_io_bawrite(&dio); 929 } else { 930 hammer2_io_bdwrite(&dio); 931 } 932 break; 933 default: 934 panic("hammer2_write_bp: bad chain type %d\n", 935 chain->bref.type); 936 /* NOT REACHED */ 937 break; 938 } 939 } 940 done: 941 if (chain) { 942 hammer2_chain_unlock(chain); 943 hammer2_chain_drop(chain); 944 } 945 if (comp_buffer) 946 objcache_put(cache_buffer_write, comp_buffer); 947 } 948 949 /* 950 * Helper 951 * 952 * Function that performs zero-checking and writing without compression, 953 * it corresponds to default zero-checking path. 954 */ 955 static 956 void 957 hammer2_zero_check_and_write(struct buf *bp, hammer2_inode_t *ip, 958 hammer2_chain_t **parentp, 959 hammer2_key_t lbase, int ioflag, int pblksize, int *errorp, 960 int check_algo) 961 { 962 hammer2_chain_t *chain; 963 964 if (test_block_zeros(bp->b_data, pblksize)) { 965 zero_write(bp, ip, parentp, lbase, errorp); 966 } else { 967 chain = hammer2_assign_physical(ip, parentp, lbase, 968 pblksize, errorp); 969 hammer2_write_bp(chain, bp, ioflag, pblksize, 970 errorp, check_algo); 971 if (chain) { 972 hammer2_chain_unlock(chain); 973 hammer2_chain_drop(chain); 974 } 975 } 976 } 977 978 /* 979 * Helper 980 * 981 * A function to test whether a block of data contains only zeros, 982 * returns TRUE (non-zero) if the block is all zeros. 983 */ 984 static 985 int 986 test_block_zeros(const char *buf, size_t bytes) 987 { 988 size_t i; 989 990 for (i = 0; i < bytes; i += sizeof(long)) { 991 if (*(const long *)(buf + i) != 0) 992 return (0); 993 } 994 return (1); 995 } 996 997 /* 998 * Helper 999 * 1000 * Function to "write" a block that contains only zeros. 1001 */ 1002 static 1003 void 1004 zero_write(struct buf *bp, hammer2_inode_t *ip, 1005 hammer2_chain_t **parentp, 1006 hammer2_key_t lbase, int *errorp __unused) 1007 { 1008 hammer2_chain_t *chain; 1009 hammer2_key_t key_dummy; 1010 int cache_index = -1; 1011 1012 chain = hammer2_chain_lookup(parentp, &key_dummy, 1013 lbase, lbase, 1014 &cache_index, 1015 HAMMER2_LOOKUP_NODATA); 1016 if (chain) { 1017 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) { 1018 hammer2_inode_data_t *wipdata; 1019 1020 hammer2_chain_modify_ip(ip, chain, 0); 1021 wipdata = &chain->data->ipdata; 1022 KKASSERT(wipdata->meta.op_flags & 1023 HAMMER2_OPFLAG_DIRECTDATA); 1024 KKASSERT(bp->b_loffset == 0); 1025 bzero(wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1026 } else { 1027 hammer2_chain_delete(*parentp, chain, 1028 HAMMER2_DELETE_PERMANENT); 1029 } 1030 hammer2_chain_unlock(chain); 1031 hammer2_chain_drop(chain); 1032 } 1033 } 1034 1035 /* 1036 * Helper 1037 * 1038 * Function to write the data as it is, without performing any sort of 1039 * compression. This function is used in path without compression and 1040 * default zero-checking path. 1041 */ 1042 static 1043 void 1044 hammer2_write_bp(hammer2_chain_t *chain, struct buf *bp, int ioflag, 1045 int pblksize, int *errorp, int check_algo) 1046 { 1047 hammer2_inode_data_t *wipdata; 1048 hammer2_io_t *dio; 1049 char *bdata; 1050 int error; 1051 1052 error = 0; /* XXX TODO below */ 1053 1054 KKASSERT(chain->flags & HAMMER2_CHAIN_MODIFIED); 1055 1056 switch(chain->bref.type) { 1057 case HAMMER2_BREF_TYPE_INODE: 1058 wipdata = &chain->data->ipdata; 1059 KKASSERT(wipdata->meta.op_flags & HAMMER2_OPFLAG_DIRECTDATA); 1060 KKASSERT(bp->b_loffset == 0); 1061 bcopy(bp->b_data, wipdata->u.data, HAMMER2_EMBEDDED_BYTES); 1062 error = 0; 1063 break; 1064 case HAMMER2_BREF_TYPE_DATA: 1065 error = hammer2_io_newnz(chain->hmp, 1066 chain->bref.data_off, 1067 chain->bytes, &dio); 1068 if (error) { 1069 hammer2_io_bqrelse(&dio); 1070 kprintf("hammer2: WRITE PATH: " 1071 "dbp bread error\n"); 1072 break; 1073 } 1074 bdata = hammer2_io_data(dio, chain->bref.data_off); 1075 1076 chain->bref.methods = HAMMER2_ENC_COMP( 1077 HAMMER2_COMP_NONE) + 1078 HAMMER2_ENC_CHECK(check_algo); 1079 bcopy(bp->b_data, bdata, chain->bytes); 1080 1081 /* 1082 * The flush code doesn't calculate check codes for 1083 * file data (doing so can result in excessive I/O), 1084 * so we do it here. 1085 */ 1086 hammer2_chain_setcheck(chain, bdata); 1087 1088 /* 1089 * Device buffer is now valid, chain is no longer in 1090 * the initial state. 1091 * 1092 * (No blockref table worries with file data) 1093 */ 1094 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL); 1095 1096 if (ioflag & IO_SYNC) { 1097 /* 1098 * Synchronous I/O requested. 1099 */ 1100 hammer2_io_bwrite(&dio); 1101 /* 1102 } else if ((ioflag & IO_DIRECT) && 1103 loff + n == pblksize) { 1104 hammer2_io_bdwrite(&dio); 1105 */ 1106 } else if (ioflag & IO_ASYNC) { 1107 hammer2_io_bawrite(&dio); 1108 } else { 1109 hammer2_io_bdwrite(&dio); 1110 } 1111 break; 1112 default: 1113 panic("hammer2_write_bp: bad chain type %d\n", 1114 chain->bref.type); 1115 /* NOT REACHED */ 1116 error = 0; 1117 break; 1118 } 1119 KKASSERT(error == 0); /* XXX TODO */ 1120 *errorp = error; 1121 } 1122