1 /* 2 * segment.c - NILFS segment constructor. 3 * 4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Ryusuke Konishi <ryusuke@osrg.net> 21 * 22 */ 23 24 #include <linux/pagemap.h> 25 #include <linux/buffer_head.h> 26 #include <linux/writeback.h> 27 #include <linux/bio.h> 28 #include <linux/completion.h> 29 #include <linux/blkdev.h> 30 #include <linux/backing-dev.h> 31 #include <linux/freezer.h> 32 #include <linux/kthread.h> 33 #include <linux/crc32.h> 34 #include <linux/pagevec.h> 35 #include "nilfs.h" 36 #include "btnode.h" 37 #include "page.h" 38 #include "segment.h" 39 #include "sufile.h" 40 #include "cpfile.h" 41 #include "ifile.h" 42 #include "segbuf.h" 43 44 45 /* 46 * Segment constructor 47 */ 48 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */ 49 50 #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments 51 appended in collection retry loop */ 52 53 /* Construction mode */ 54 enum { 55 SC_LSEG_SR = 1, /* Make a logical segment having a super root */ 56 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make 57 a logical segment without a super root */ 58 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without 59 creating a checkpoint */ 60 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without 61 a checkpoint */ 62 }; 63 64 /* Stage numbers of dirty block collection */ 65 enum { 66 NILFS_ST_INIT = 0, 67 NILFS_ST_GC, /* Collecting dirty blocks for GC */ 68 NILFS_ST_FILE, 69 NILFS_ST_IFILE, 70 NILFS_ST_CPFILE, 71 NILFS_ST_SUFILE, 72 NILFS_ST_DAT, 73 NILFS_ST_SR, /* Super root */ 74 NILFS_ST_DSYNC, /* Data sync blocks */ 75 NILFS_ST_DONE, 76 }; 77 78 /* State flags of collection */ 79 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ 80 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ 81 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */ 82 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED) 83 84 /* Operations depending on the construction mode and file type */ 85 struct nilfs_sc_operations { 86 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, 87 struct inode *); 88 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, 89 struct inode *); 90 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, 91 struct inode *); 92 void (*write_data_binfo)(struct nilfs_sc_info *, 93 struct nilfs_segsum_pointer *, 94 union nilfs_binfo *); 95 void (*write_node_binfo)(struct nilfs_sc_info *, 96 struct nilfs_segsum_pointer *, 97 union nilfs_binfo *); 98 }; 99 100 /* 101 * Other definitions 102 */ 103 static void nilfs_segctor_start_timer(struct nilfs_sc_info *); 104 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); 105 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); 106 static void nilfs_dispose_list(struct nilfs_sb_info *, struct list_head *, 107 int); 108 109 #define nilfs_cnt32_gt(a, b) \ 110 (typecheck(__u32, a) && typecheck(__u32, b) && \ 111 ((__s32)(b) - (__s32)(a) < 0)) 112 #define nilfs_cnt32_ge(a, b) \ 113 (typecheck(__u32, a) && typecheck(__u32, b) && \ 114 ((__s32)(a) - (__s32)(b) >= 0)) 115 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a) 116 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a) 117 118 /* 119 * Transaction 120 */ 121 static struct kmem_cache *nilfs_transaction_cachep; 122 123 /** 124 * nilfs_init_transaction_cache - create a cache for nilfs_transaction_info 125 * 126 * nilfs_init_transaction_cache() creates a slab cache for the struct 127 * nilfs_transaction_info. 128 * 129 * Return Value: On success, it returns 0. On error, one of the following 130 * negative error code is returned. 131 * 132 * %-ENOMEM - Insufficient memory available. 133 */ 134 int nilfs_init_transaction_cache(void) 135 { 136 nilfs_transaction_cachep = 137 kmem_cache_create("nilfs2_transaction_cache", 138 sizeof(struct nilfs_transaction_info), 139 0, SLAB_RECLAIM_ACCOUNT, NULL); 140 return (nilfs_transaction_cachep == NULL) ? -ENOMEM : 0; 141 } 142 143 /** 144 * nilfs_detroy_transaction_cache - destroy the cache for transaction info 145 * 146 * nilfs_destroy_transaction_cache() frees the slab cache for the struct 147 * nilfs_transaction_info. 148 */ 149 void nilfs_destroy_transaction_cache(void) 150 { 151 kmem_cache_destroy(nilfs_transaction_cachep); 152 } 153 154 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti) 155 { 156 struct nilfs_transaction_info *cur_ti = current->journal_info; 157 void *save = NULL; 158 159 if (cur_ti) { 160 if (cur_ti->ti_magic == NILFS_TI_MAGIC) 161 return ++cur_ti->ti_count; 162 else { 163 /* 164 * If journal_info field is occupied by other FS, 165 * it is saved and will be restored on 166 * nilfs_transaction_commit(). 167 */ 168 printk(KERN_WARNING 169 "NILFS warning: journal info from a different " 170 "FS\n"); 171 save = current->journal_info; 172 } 173 } 174 if (!ti) { 175 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); 176 if (!ti) 177 return -ENOMEM; 178 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; 179 } else { 180 ti->ti_flags = 0; 181 } 182 ti->ti_count = 0; 183 ti->ti_save = save; 184 ti->ti_magic = NILFS_TI_MAGIC; 185 current->journal_info = ti; 186 return 0; 187 } 188 189 /** 190 * nilfs_transaction_begin - start indivisible file operations. 191 * @sb: super block 192 * @ti: nilfs_transaction_info 193 * @vacancy_check: flags for vacancy rate checks 194 * 195 * nilfs_transaction_begin() acquires a reader/writer semaphore, called 196 * the segment semaphore, to make a segment construction and write tasks 197 * exclusive. The function is used with nilfs_transaction_commit() in pairs. 198 * The region enclosed by these two functions can be nested. To avoid a 199 * deadlock, the semaphore is only acquired or released in the outermost call. 200 * 201 * This function allocates a nilfs_transaction_info struct to keep context 202 * information on it. It is initialized and hooked onto the current task in 203 * the outermost call. If a pre-allocated struct is given to @ti, it is used 204 * instead; othewise a new struct is assigned from a slab. 205 * 206 * When @vacancy_check flag is set, this function will check the amount of 207 * free space, and will wait for the GC to reclaim disk space if low capacity. 208 * 209 * Return Value: On success, 0 is returned. On error, one of the following 210 * negative error code is returned. 211 * 212 * %-ENOMEM - Insufficient memory available. 213 * 214 * %-ENOSPC - No space left on device 215 */ 216 int nilfs_transaction_begin(struct super_block *sb, 217 struct nilfs_transaction_info *ti, 218 int vacancy_check) 219 { 220 struct nilfs_sb_info *sbi; 221 struct the_nilfs *nilfs; 222 int ret = nilfs_prepare_segment_lock(ti); 223 224 if (unlikely(ret < 0)) 225 return ret; 226 if (ret > 0) 227 return 0; 228 229 sbi = NILFS_SB(sb); 230 nilfs = sbi->s_nilfs; 231 down_read(&nilfs->ns_segctor_sem); 232 if (vacancy_check && nilfs_near_disk_full(nilfs)) { 233 up_read(&nilfs->ns_segctor_sem); 234 ret = -ENOSPC; 235 goto failed; 236 } 237 return 0; 238 239 failed: 240 ti = current->journal_info; 241 current->journal_info = ti->ti_save; 242 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 243 kmem_cache_free(nilfs_transaction_cachep, ti); 244 return ret; 245 } 246 247 /** 248 * nilfs_transaction_commit - commit indivisible file operations. 249 * @sb: super block 250 * 251 * nilfs_transaction_commit() releases the read semaphore which is 252 * acquired by nilfs_transaction_begin(). This is only performed 253 * in outermost call of this function. If a commit flag is set, 254 * nilfs_transaction_commit() sets a timer to start the segment 255 * constructor. If a sync flag is set, it starts construction 256 * directly. 257 */ 258 int nilfs_transaction_commit(struct super_block *sb) 259 { 260 struct nilfs_transaction_info *ti = current->journal_info; 261 struct nilfs_sb_info *sbi; 262 struct nilfs_sc_info *sci; 263 int err = 0; 264 265 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 266 ti->ti_flags |= NILFS_TI_COMMIT; 267 if (ti->ti_count > 0) { 268 ti->ti_count--; 269 return 0; 270 } 271 sbi = NILFS_SB(sb); 272 sci = NILFS_SC(sbi); 273 if (sci != NULL) { 274 if (ti->ti_flags & NILFS_TI_COMMIT) 275 nilfs_segctor_start_timer(sci); 276 if (atomic_read(&sbi->s_nilfs->ns_ndirtyblks) > 277 sci->sc_watermark) 278 nilfs_segctor_do_flush(sci, 0); 279 } 280 up_read(&sbi->s_nilfs->ns_segctor_sem); 281 current->journal_info = ti->ti_save; 282 283 if (ti->ti_flags & NILFS_TI_SYNC) 284 err = nilfs_construct_segment(sb); 285 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 286 kmem_cache_free(nilfs_transaction_cachep, ti); 287 return err; 288 } 289 290 void nilfs_transaction_abort(struct super_block *sb) 291 { 292 struct nilfs_transaction_info *ti = current->journal_info; 293 294 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 295 if (ti->ti_count > 0) { 296 ti->ti_count--; 297 return; 298 } 299 up_read(&NILFS_SB(sb)->s_nilfs->ns_segctor_sem); 300 301 current->journal_info = ti->ti_save; 302 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 303 kmem_cache_free(nilfs_transaction_cachep, ti); 304 } 305 306 void nilfs_relax_pressure_in_lock(struct super_block *sb) 307 { 308 struct nilfs_sb_info *sbi = NILFS_SB(sb); 309 struct nilfs_sc_info *sci = NILFS_SC(sbi); 310 struct the_nilfs *nilfs = sbi->s_nilfs; 311 312 if (!sci || !sci->sc_flush_request) 313 return; 314 315 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 316 up_read(&nilfs->ns_segctor_sem); 317 318 down_write(&nilfs->ns_segctor_sem); 319 if (sci->sc_flush_request && 320 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { 321 struct nilfs_transaction_info *ti = current->journal_info; 322 323 ti->ti_flags |= NILFS_TI_WRITER; 324 nilfs_segctor_do_immediate_flush(sci); 325 ti->ti_flags &= ~NILFS_TI_WRITER; 326 } 327 downgrade_write(&nilfs->ns_segctor_sem); 328 } 329 330 static void nilfs_transaction_lock(struct nilfs_sb_info *sbi, 331 struct nilfs_transaction_info *ti, 332 int gcflag) 333 { 334 struct nilfs_transaction_info *cur_ti = current->journal_info; 335 336 WARN_ON(cur_ti); 337 ti->ti_flags = NILFS_TI_WRITER; 338 ti->ti_count = 0; 339 ti->ti_save = cur_ti; 340 ti->ti_magic = NILFS_TI_MAGIC; 341 INIT_LIST_HEAD(&ti->ti_garbage); 342 current->journal_info = ti; 343 344 for (;;) { 345 down_write(&sbi->s_nilfs->ns_segctor_sem); 346 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &NILFS_SC(sbi)->sc_flags)) 347 break; 348 349 nilfs_segctor_do_immediate_flush(NILFS_SC(sbi)); 350 351 up_write(&sbi->s_nilfs->ns_segctor_sem); 352 yield(); 353 } 354 if (gcflag) 355 ti->ti_flags |= NILFS_TI_GC; 356 } 357 358 static void nilfs_transaction_unlock(struct nilfs_sb_info *sbi) 359 { 360 struct nilfs_transaction_info *ti = current->journal_info; 361 362 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 363 BUG_ON(ti->ti_count > 0); 364 365 up_write(&sbi->s_nilfs->ns_segctor_sem); 366 current->journal_info = ti->ti_save; 367 if (!list_empty(&ti->ti_garbage)) 368 nilfs_dispose_list(sbi, &ti->ti_garbage, 0); 369 } 370 371 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, 372 struct nilfs_segsum_pointer *ssp, 373 unsigned bytes) 374 { 375 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 376 unsigned blocksize = sci->sc_super->s_blocksize; 377 void *p; 378 379 if (unlikely(ssp->offset + bytes > blocksize)) { 380 ssp->offset = 0; 381 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, 382 &segbuf->sb_segsum_buffers)); 383 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); 384 } 385 p = ssp->bh->b_data + ssp->offset; 386 ssp->offset += bytes; 387 return p; 388 } 389 390 /** 391 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer 392 * @sci: nilfs_sc_info 393 */ 394 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) 395 { 396 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 397 struct buffer_head *sumbh; 398 unsigned sumbytes; 399 unsigned flags = 0; 400 int err; 401 402 if (nilfs_doing_gc()) 403 flags = NILFS_SS_GC; 404 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime); 405 if (unlikely(err)) 406 return err; 407 408 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 409 sumbytes = segbuf->sb_sum.sumbytes; 410 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; 411 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; 412 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 413 return 0; 414 } 415 416 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) 417 { 418 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 419 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) 420 return -E2BIG; /* The current segment is filled up 421 (internal code) */ 422 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); 423 return nilfs_segctor_reset_segment_buffer(sci); 424 } 425 426 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) 427 { 428 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 429 int err; 430 431 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { 432 err = nilfs_segctor_feed_segment(sci); 433 if (err) 434 return err; 435 segbuf = sci->sc_curseg; 436 } 437 err = nilfs_segbuf_extend_payload(segbuf, &sci->sc_super_root); 438 if (likely(!err)) 439 segbuf->sb_sum.flags |= NILFS_SS_SR; 440 return err; 441 } 442 443 /* 444 * Functions for making segment summary and payloads 445 */ 446 static int nilfs_segctor_segsum_block_required( 447 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, 448 unsigned binfo_size) 449 { 450 unsigned blocksize = sci->sc_super->s_blocksize; 451 /* Size of finfo and binfo is enough small against blocksize */ 452 453 return ssp->offset + binfo_size + 454 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > 455 blocksize; 456 } 457 458 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, 459 struct inode *inode) 460 { 461 sci->sc_curseg->sb_sum.nfinfo++; 462 sci->sc_binfo_ptr = sci->sc_finfo_ptr; 463 nilfs_segctor_map_segsum_entry( 464 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); 465 466 if (inode->i_sb && !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 467 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 468 /* skip finfo */ 469 } 470 471 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, 472 struct inode *inode) 473 { 474 struct nilfs_finfo *finfo; 475 struct nilfs_inode_info *ii; 476 struct nilfs_segment_buffer *segbuf; 477 478 if (sci->sc_blk_cnt == 0) 479 return; 480 481 ii = NILFS_I(inode); 482 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, 483 sizeof(*finfo)); 484 finfo->fi_ino = cpu_to_le64(inode->i_ino); 485 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); 486 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); 487 finfo->fi_cno = cpu_to_le64(ii->i_cno); 488 489 segbuf = sci->sc_curseg; 490 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + 491 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); 492 sci->sc_finfo_ptr = sci->sc_binfo_ptr; 493 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 494 } 495 496 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, 497 struct buffer_head *bh, 498 struct inode *inode, 499 unsigned binfo_size) 500 { 501 struct nilfs_segment_buffer *segbuf; 502 int required, err = 0; 503 504 retry: 505 segbuf = sci->sc_curseg; 506 required = nilfs_segctor_segsum_block_required( 507 sci, &sci->sc_binfo_ptr, binfo_size); 508 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { 509 nilfs_segctor_end_finfo(sci, inode); 510 err = nilfs_segctor_feed_segment(sci); 511 if (err) 512 return err; 513 goto retry; 514 } 515 if (unlikely(required)) { 516 err = nilfs_segbuf_extend_segsum(segbuf); 517 if (unlikely(err)) 518 goto failed; 519 } 520 if (sci->sc_blk_cnt == 0) 521 nilfs_segctor_begin_finfo(sci, inode); 522 523 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); 524 /* Substitution to vblocknr is delayed until update_blocknr() */ 525 nilfs_segbuf_add_file_buffer(segbuf, bh); 526 sci->sc_blk_cnt++; 527 failed: 528 return err; 529 } 530 531 static int nilfs_handle_bmap_error(int err, const char *fname, 532 struct inode *inode, struct super_block *sb) 533 { 534 if (err == -EINVAL) { 535 nilfs_error(sb, fname, "broken bmap (inode=%lu)\n", 536 inode->i_ino); 537 err = -EIO; 538 } 539 return err; 540 } 541 542 /* 543 * Callback functions that enumerate, mark, and collect dirty blocks 544 */ 545 static int nilfs_collect_file_data(struct nilfs_sc_info *sci, 546 struct buffer_head *bh, struct inode *inode) 547 { 548 int err; 549 550 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 551 if (unlikely(err < 0)) 552 return nilfs_handle_bmap_error(err, __func__, inode, 553 sci->sc_super); 554 555 err = nilfs_segctor_add_file_block(sci, bh, inode, 556 sizeof(struct nilfs_binfo_v)); 557 if (!err) 558 sci->sc_datablk_cnt++; 559 return err; 560 } 561 562 static int nilfs_collect_file_node(struct nilfs_sc_info *sci, 563 struct buffer_head *bh, 564 struct inode *inode) 565 { 566 int err; 567 568 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 569 if (unlikely(err < 0)) 570 return nilfs_handle_bmap_error(err, __func__, inode, 571 sci->sc_super); 572 return 0; 573 } 574 575 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, 576 struct buffer_head *bh, 577 struct inode *inode) 578 { 579 WARN_ON(!buffer_dirty(bh)); 580 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 581 } 582 583 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, 584 struct nilfs_segsum_pointer *ssp, 585 union nilfs_binfo *binfo) 586 { 587 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( 588 sci, ssp, sizeof(*binfo_v)); 589 *binfo_v = binfo->bi_v; 590 } 591 592 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, 593 struct nilfs_segsum_pointer *ssp, 594 union nilfs_binfo *binfo) 595 { 596 __le64 *vblocknr = nilfs_segctor_map_segsum_entry( 597 sci, ssp, sizeof(*vblocknr)); 598 *vblocknr = binfo->bi_v.bi_vblocknr; 599 } 600 601 struct nilfs_sc_operations nilfs_sc_file_ops = { 602 .collect_data = nilfs_collect_file_data, 603 .collect_node = nilfs_collect_file_node, 604 .collect_bmap = nilfs_collect_file_bmap, 605 .write_data_binfo = nilfs_write_file_data_binfo, 606 .write_node_binfo = nilfs_write_file_node_binfo, 607 }; 608 609 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, 610 struct buffer_head *bh, struct inode *inode) 611 { 612 int err; 613 614 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 615 if (unlikely(err < 0)) 616 return nilfs_handle_bmap_error(err, __func__, inode, 617 sci->sc_super); 618 619 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 620 if (!err) 621 sci->sc_datablk_cnt++; 622 return err; 623 } 624 625 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, 626 struct buffer_head *bh, struct inode *inode) 627 { 628 WARN_ON(!buffer_dirty(bh)); 629 return nilfs_segctor_add_file_block(sci, bh, inode, 630 sizeof(struct nilfs_binfo_dat)); 631 } 632 633 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, 634 struct nilfs_segsum_pointer *ssp, 635 union nilfs_binfo *binfo) 636 { 637 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, 638 sizeof(*blkoff)); 639 *blkoff = binfo->bi_dat.bi_blkoff; 640 } 641 642 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, 643 struct nilfs_segsum_pointer *ssp, 644 union nilfs_binfo *binfo) 645 { 646 struct nilfs_binfo_dat *binfo_dat = 647 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); 648 *binfo_dat = binfo->bi_dat; 649 } 650 651 struct nilfs_sc_operations nilfs_sc_dat_ops = { 652 .collect_data = nilfs_collect_dat_data, 653 .collect_node = nilfs_collect_file_node, 654 .collect_bmap = nilfs_collect_dat_bmap, 655 .write_data_binfo = nilfs_write_dat_data_binfo, 656 .write_node_binfo = nilfs_write_dat_node_binfo, 657 }; 658 659 struct nilfs_sc_operations nilfs_sc_dsync_ops = { 660 .collect_data = nilfs_collect_file_data, 661 .collect_node = NULL, 662 .collect_bmap = NULL, 663 .write_data_binfo = nilfs_write_file_data_binfo, 664 .write_node_binfo = NULL, 665 }; 666 667 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, 668 struct list_head *listp, 669 size_t nlimit, 670 loff_t start, loff_t end) 671 { 672 struct address_space *mapping = inode->i_mapping; 673 struct pagevec pvec; 674 pgoff_t index = 0, last = ULONG_MAX; 675 size_t ndirties = 0; 676 int i; 677 678 if (unlikely(start != 0 || end != LLONG_MAX)) { 679 /* 680 * A valid range is given for sync-ing data pages. The 681 * range is rounded to per-page; extra dirty buffers 682 * may be included if blocksize < pagesize. 683 */ 684 index = start >> PAGE_SHIFT; 685 last = end >> PAGE_SHIFT; 686 } 687 pagevec_init(&pvec, 0); 688 repeat: 689 if (unlikely(index > last) || 690 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 691 min_t(pgoff_t, last - index, 692 PAGEVEC_SIZE - 1) + 1)) 693 return ndirties; 694 695 for (i = 0; i < pagevec_count(&pvec); i++) { 696 struct buffer_head *bh, *head; 697 struct page *page = pvec.pages[i]; 698 699 if (unlikely(page->index > last)) 700 break; 701 702 if (mapping->host) { 703 lock_page(page); 704 if (!page_has_buffers(page)) 705 create_empty_buffers(page, 706 1 << inode->i_blkbits, 0); 707 unlock_page(page); 708 } 709 710 bh = head = page_buffers(page); 711 do { 712 if (!buffer_dirty(bh)) 713 continue; 714 get_bh(bh); 715 list_add_tail(&bh->b_assoc_buffers, listp); 716 ndirties++; 717 if (unlikely(ndirties >= nlimit)) { 718 pagevec_release(&pvec); 719 cond_resched(); 720 return ndirties; 721 } 722 } while (bh = bh->b_this_page, bh != head); 723 } 724 pagevec_release(&pvec); 725 cond_resched(); 726 goto repeat; 727 } 728 729 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 730 struct list_head *listp) 731 { 732 struct nilfs_inode_info *ii = NILFS_I(inode); 733 struct address_space *mapping = &ii->i_btnode_cache; 734 struct pagevec pvec; 735 struct buffer_head *bh, *head; 736 unsigned int i; 737 pgoff_t index = 0; 738 739 pagevec_init(&pvec, 0); 740 741 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 742 PAGEVEC_SIZE)) { 743 for (i = 0; i < pagevec_count(&pvec); i++) { 744 bh = head = page_buffers(pvec.pages[i]); 745 do { 746 if (buffer_dirty(bh)) { 747 get_bh(bh); 748 list_add_tail(&bh->b_assoc_buffers, 749 listp); 750 } 751 bh = bh->b_this_page; 752 } while (bh != head); 753 } 754 pagevec_release(&pvec); 755 cond_resched(); 756 } 757 } 758 759 static void nilfs_dispose_list(struct nilfs_sb_info *sbi, 760 struct list_head *head, int force) 761 { 762 struct nilfs_inode_info *ii, *n; 763 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 764 unsigned nv = 0; 765 766 while (!list_empty(head)) { 767 spin_lock(&sbi->s_inode_lock); 768 list_for_each_entry_safe(ii, n, head, i_dirty) { 769 list_del_init(&ii->i_dirty); 770 if (force) { 771 if (unlikely(ii->i_bh)) { 772 brelse(ii->i_bh); 773 ii->i_bh = NULL; 774 } 775 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 776 set_bit(NILFS_I_QUEUED, &ii->i_state); 777 list_add_tail(&ii->i_dirty, 778 &sbi->s_dirty_files); 779 continue; 780 } 781 ivec[nv++] = ii; 782 if (nv == SC_N_INODEVEC) 783 break; 784 } 785 spin_unlock(&sbi->s_inode_lock); 786 787 for (pii = ivec; nv > 0; pii++, nv--) 788 iput(&(*pii)->vfs_inode); 789 } 790 } 791 792 static int nilfs_test_metadata_dirty(struct nilfs_sb_info *sbi) 793 { 794 struct the_nilfs *nilfs = sbi->s_nilfs; 795 int ret = 0; 796 797 if (nilfs_mdt_fetch_dirty(sbi->s_ifile)) 798 ret++; 799 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 800 ret++; 801 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 802 ret++; 803 if (ret || nilfs_doing_gc()) 804 if (nilfs_mdt_fetch_dirty(nilfs_dat_inode(nilfs))) 805 ret++; 806 return ret; 807 } 808 809 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 810 { 811 return list_empty(&sci->sc_dirty_files) && 812 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 813 sci->sc_nfreesegs == 0 && 814 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 815 } 816 817 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 818 { 819 struct nilfs_sb_info *sbi = sci->sc_sbi; 820 int ret = 0; 821 822 if (nilfs_test_metadata_dirty(sbi)) 823 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 824 825 spin_lock(&sbi->s_inode_lock); 826 if (list_empty(&sbi->s_dirty_files) && nilfs_segctor_clean(sci)) 827 ret++; 828 829 spin_unlock(&sbi->s_inode_lock); 830 return ret; 831 } 832 833 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 834 { 835 struct nilfs_sb_info *sbi = sci->sc_sbi; 836 struct the_nilfs *nilfs = sbi->s_nilfs; 837 838 nilfs_mdt_clear_dirty(sbi->s_ifile); 839 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 840 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 841 nilfs_mdt_clear_dirty(nilfs_dat_inode(nilfs)); 842 } 843 844 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 845 { 846 struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; 847 struct buffer_head *bh_cp; 848 struct nilfs_checkpoint *raw_cp; 849 int err; 850 851 /* XXX: this interface will be changed */ 852 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 853 &raw_cp, &bh_cp); 854 if (likely(!err)) { 855 /* The following code is duplicated with cpfile. But, it is 856 needed to collect the checkpoint even if it was not newly 857 created */ 858 nilfs_mdt_mark_buffer_dirty(bh_cp); 859 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 860 nilfs_cpfile_put_checkpoint( 861 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 862 } else 863 WARN_ON(err == -EINVAL || err == -ENOENT); 864 865 return err; 866 } 867 868 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 869 { 870 struct nilfs_sb_info *sbi = sci->sc_sbi; 871 struct the_nilfs *nilfs = sbi->s_nilfs; 872 struct buffer_head *bh_cp; 873 struct nilfs_checkpoint *raw_cp; 874 int err; 875 876 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 877 &raw_cp, &bh_cp); 878 if (unlikely(err)) { 879 WARN_ON(err == -EINVAL || err == -ENOENT); 880 goto failed_ibh; 881 } 882 raw_cp->cp_snapshot_list.ssl_next = 0; 883 raw_cp->cp_snapshot_list.ssl_prev = 0; 884 raw_cp->cp_inodes_count = 885 cpu_to_le64(atomic_read(&sbi->s_inodes_count)); 886 raw_cp->cp_blocks_count = 887 cpu_to_le64(atomic_read(&sbi->s_blocks_count)); 888 raw_cp->cp_nblk_inc = 889 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 890 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 891 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 892 893 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 894 nilfs_checkpoint_clear_minor(raw_cp); 895 else 896 nilfs_checkpoint_set_minor(raw_cp); 897 898 nilfs_write_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode, 1); 899 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 900 return 0; 901 902 failed_ibh: 903 return err; 904 } 905 906 static void nilfs_fill_in_file_bmap(struct inode *ifile, 907 struct nilfs_inode_info *ii) 908 909 { 910 struct buffer_head *ibh; 911 struct nilfs_inode *raw_inode; 912 913 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 914 ibh = ii->i_bh; 915 BUG_ON(!ibh); 916 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 917 ibh); 918 nilfs_bmap_write(ii->i_bmap, raw_inode); 919 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 920 } 921 } 922 923 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci, 924 struct inode *ifile) 925 { 926 struct nilfs_inode_info *ii; 927 928 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 929 nilfs_fill_in_file_bmap(ifile, ii); 930 set_bit(NILFS_I_COLLECTED, &ii->i_state); 931 } 932 } 933 934 /* 935 * CRC calculation routines 936 */ 937 static void nilfs_fill_in_super_root_crc(struct buffer_head *bh_sr, u32 seed) 938 { 939 struct nilfs_super_root *raw_sr = 940 (struct nilfs_super_root *)bh_sr->b_data; 941 u32 crc; 942 943 crc = crc32_le(seed, 944 (unsigned char *)raw_sr + sizeof(raw_sr->sr_sum), 945 NILFS_SR_BYTES - sizeof(raw_sr->sr_sum)); 946 raw_sr->sr_sum = cpu_to_le32(crc); 947 } 948 949 static void nilfs_segctor_fill_in_checksums(struct nilfs_sc_info *sci, 950 u32 seed) 951 { 952 struct nilfs_segment_buffer *segbuf; 953 954 if (sci->sc_super_root) 955 nilfs_fill_in_super_root_crc(sci->sc_super_root, seed); 956 957 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 958 nilfs_segbuf_fill_in_segsum_crc(segbuf, seed); 959 nilfs_segbuf_fill_in_data_crc(segbuf, seed); 960 } 961 } 962 963 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 964 struct the_nilfs *nilfs) 965 { 966 struct buffer_head *bh_sr = sci->sc_super_root; 967 struct nilfs_super_root *raw_sr = 968 (struct nilfs_super_root *)bh_sr->b_data; 969 unsigned isz = nilfs->ns_inode_size; 970 971 raw_sr->sr_bytes = cpu_to_le16(NILFS_SR_BYTES); 972 raw_sr->sr_nongc_ctime 973 = cpu_to_le64(nilfs_doing_gc() ? 974 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 975 raw_sr->sr_flags = 0; 976 977 nilfs_mdt_write_inode_direct( 978 nilfs_dat_inode(nilfs), bh_sr, NILFS_SR_DAT_OFFSET(isz)); 979 nilfs_mdt_write_inode_direct( 980 nilfs->ns_cpfile, bh_sr, NILFS_SR_CPFILE_OFFSET(isz)); 981 nilfs_mdt_write_inode_direct( 982 nilfs->ns_sufile, bh_sr, NILFS_SR_SUFILE_OFFSET(isz)); 983 } 984 985 static void nilfs_redirty_inodes(struct list_head *head) 986 { 987 struct nilfs_inode_info *ii; 988 989 list_for_each_entry(ii, head, i_dirty) { 990 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 991 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 992 } 993 } 994 995 static void nilfs_drop_collected_inodes(struct list_head *head) 996 { 997 struct nilfs_inode_info *ii; 998 999 list_for_each_entry(ii, head, i_dirty) { 1000 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 1001 continue; 1002 1003 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state); 1004 set_bit(NILFS_I_UPDATED, &ii->i_state); 1005 } 1006 } 1007 1008 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 1009 struct inode *inode, 1010 struct list_head *listp, 1011 int (*collect)(struct nilfs_sc_info *, 1012 struct buffer_head *, 1013 struct inode *)) 1014 { 1015 struct buffer_head *bh, *n; 1016 int err = 0; 1017 1018 if (collect) { 1019 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 1020 list_del_init(&bh->b_assoc_buffers); 1021 err = collect(sci, bh, inode); 1022 brelse(bh); 1023 if (unlikely(err)) 1024 goto dispose_buffers; 1025 } 1026 return 0; 1027 } 1028 1029 dispose_buffers: 1030 while (!list_empty(listp)) { 1031 bh = list_entry(listp->next, struct buffer_head, 1032 b_assoc_buffers); 1033 list_del_init(&bh->b_assoc_buffers); 1034 brelse(bh); 1035 } 1036 return err; 1037 } 1038 1039 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 1040 { 1041 /* Remaining number of blocks within segment buffer */ 1042 return sci->sc_segbuf_nblocks - 1043 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 1044 } 1045 1046 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 1047 struct inode *inode, 1048 struct nilfs_sc_operations *sc_ops) 1049 { 1050 LIST_HEAD(data_buffers); 1051 LIST_HEAD(node_buffers); 1052 int err; 1053 1054 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1055 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1056 1057 n = nilfs_lookup_dirty_data_buffers( 1058 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 1059 if (n > rest) { 1060 err = nilfs_segctor_apply_buffers( 1061 sci, inode, &data_buffers, 1062 sc_ops->collect_data); 1063 BUG_ON(!err); /* always receive -E2BIG or true error */ 1064 goto break_or_fail; 1065 } 1066 } 1067 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 1068 1069 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1070 err = nilfs_segctor_apply_buffers( 1071 sci, inode, &data_buffers, sc_ops->collect_data); 1072 if (unlikely(err)) { 1073 /* dispose node list */ 1074 nilfs_segctor_apply_buffers( 1075 sci, inode, &node_buffers, NULL); 1076 goto break_or_fail; 1077 } 1078 sci->sc_stage.flags |= NILFS_CF_NODE; 1079 } 1080 /* Collect node */ 1081 err = nilfs_segctor_apply_buffers( 1082 sci, inode, &node_buffers, sc_ops->collect_node); 1083 if (unlikely(err)) 1084 goto break_or_fail; 1085 1086 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1087 err = nilfs_segctor_apply_buffers( 1088 sci, inode, &node_buffers, sc_ops->collect_bmap); 1089 if (unlikely(err)) 1090 goto break_or_fail; 1091 1092 nilfs_segctor_end_finfo(sci, inode); 1093 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1094 1095 break_or_fail: 1096 return err; 1097 } 1098 1099 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1100 struct inode *inode) 1101 { 1102 LIST_HEAD(data_buffers); 1103 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1104 int err; 1105 1106 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1107 sci->sc_dsync_start, 1108 sci->sc_dsync_end); 1109 1110 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1111 nilfs_collect_file_data); 1112 if (!err) { 1113 nilfs_segctor_end_finfo(sci, inode); 1114 BUG_ON(n > rest); 1115 /* always receive -E2BIG or true error if n > rest */ 1116 } 1117 return err; 1118 } 1119 1120 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1121 { 1122 struct nilfs_sb_info *sbi = sci->sc_sbi; 1123 struct the_nilfs *nilfs = sbi->s_nilfs; 1124 struct list_head *head; 1125 struct nilfs_inode_info *ii; 1126 size_t ndone; 1127 int err = 0; 1128 1129 switch (sci->sc_stage.scnt) { 1130 case NILFS_ST_INIT: 1131 /* Pre-processes */ 1132 sci->sc_stage.flags = 0; 1133 1134 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1135 sci->sc_nblk_inc = 0; 1136 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1137 if (mode == SC_LSEG_DSYNC) { 1138 sci->sc_stage.scnt = NILFS_ST_DSYNC; 1139 goto dsync_mode; 1140 } 1141 } 1142 1143 sci->sc_stage.dirty_file_ptr = NULL; 1144 sci->sc_stage.gc_inode_ptr = NULL; 1145 if (mode == SC_FLUSH_DAT) { 1146 sci->sc_stage.scnt = NILFS_ST_DAT; 1147 goto dat_stage; 1148 } 1149 sci->sc_stage.scnt++; /* Fall through */ 1150 case NILFS_ST_GC: 1151 if (nilfs_doing_gc()) { 1152 head = &sci->sc_gc_inodes; 1153 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1154 head, i_dirty); 1155 list_for_each_entry_continue(ii, head, i_dirty) { 1156 err = nilfs_segctor_scan_file( 1157 sci, &ii->vfs_inode, 1158 &nilfs_sc_file_ops); 1159 if (unlikely(err)) { 1160 sci->sc_stage.gc_inode_ptr = list_entry( 1161 ii->i_dirty.prev, 1162 struct nilfs_inode_info, 1163 i_dirty); 1164 goto break_or_fail; 1165 } 1166 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1167 } 1168 sci->sc_stage.gc_inode_ptr = NULL; 1169 } 1170 sci->sc_stage.scnt++; /* Fall through */ 1171 case NILFS_ST_FILE: 1172 head = &sci->sc_dirty_files; 1173 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1174 i_dirty); 1175 list_for_each_entry_continue(ii, head, i_dirty) { 1176 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1177 1178 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1179 &nilfs_sc_file_ops); 1180 if (unlikely(err)) { 1181 sci->sc_stage.dirty_file_ptr = 1182 list_entry(ii->i_dirty.prev, 1183 struct nilfs_inode_info, 1184 i_dirty); 1185 goto break_or_fail; 1186 } 1187 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1188 /* XXX: required ? */ 1189 } 1190 sci->sc_stage.dirty_file_ptr = NULL; 1191 if (mode == SC_FLUSH_FILE) { 1192 sci->sc_stage.scnt = NILFS_ST_DONE; 1193 return 0; 1194 } 1195 sci->sc_stage.scnt++; 1196 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1197 /* Fall through */ 1198 case NILFS_ST_IFILE: 1199 err = nilfs_segctor_scan_file(sci, sbi->s_ifile, 1200 &nilfs_sc_file_ops); 1201 if (unlikely(err)) 1202 break; 1203 sci->sc_stage.scnt++; 1204 /* Creating a checkpoint */ 1205 err = nilfs_segctor_create_checkpoint(sci); 1206 if (unlikely(err)) 1207 break; 1208 /* Fall through */ 1209 case NILFS_ST_CPFILE: 1210 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1211 &nilfs_sc_file_ops); 1212 if (unlikely(err)) 1213 break; 1214 sci->sc_stage.scnt++; /* Fall through */ 1215 case NILFS_ST_SUFILE: 1216 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1217 sci->sc_nfreesegs, &ndone); 1218 if (unlikely(err)) { 1219 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1220 sci->sc_freesegs, ndone, 1221 NULL); 1222 break; 1223 } 1224 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1225 1226 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1227 &nilfs_sc_file_ops); 1228 if (unlikely(err)) 1229 break; 1230 sci->sc_stage.scnt++; /* Fall through */ 1231 case NILFS_ST_DAT: 1232 dat_stage: 1233 err = nilfs_segctor_scan_file(sci, nilfs_dat_inode(nilfs), 1234 &nilfs_sc_dat_ops); 1235 if (unlikely(err)) 1236 break; 1237 if (mode == SC_FLUSH_DAT) { 1238 sci->sc_stage.scnt = NILFS_ST_DONE; 1239 return 0; 1240 } 1241 sci->sc_stage.scnt++; /* Fall through */ 1242 case NILFS_ST_SR: 1243 if (mode == SC_LSEG_SR) { 1244 /* Appending a super root */ 1245 err = nilfs_segctor_add_super_root(sci); 1246 if (unlikely(err)) 1247 break; 1248 } 1249 /* End of a logical segment */ 1250 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1251 sci->sc_stage.scnt = NILFS_ST_DONE; 1252 return 0; 1253 case NILFS_ST_DSYNC: 1254 dsync_mode: 1255 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1256 ii = sci->sc_dsync_inode; 1257 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1258 break; 1259 1260 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1261 if (unlikely(err)) 1262 break; 1263 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1264 sci->sc_stage.scnt = NILFS_ST_DONE; 1265 return 0; 1266 case NILFS_ST_DONE: 1267 return 0; 1268 default: 1269 BUG(); 1270 } 1271 1272 break_or_fail: 1273 return err; 1274 } 1275 1276 static int nilfs_touch_segusage(struct inode *sufile, __u64 segnum) 1277 { 1278 struct buffer_head *bh_su; 1279 struct nilfs_segment_usage *raw_su; 1280 int err; 1281 1282 err = nilfs_sufile_get_segment_usage(sufile, segnum, &raw_su, &bh_su); 1283 if (unlikely(err)) 1284 return err; 1285 nilfs_mdt_mark_buffer_dirty(bh_su); 1286 nilfs_mdt_mark_dirty(sufile); 1287 nilfs_sufile_put_segment_usage(sufile, segnum, bh_su); 1288 return 0; 1289 } 1290 1291 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1292 struct the_nilfs *nilfs) 1293 { 1294 struct nilfs_segment_buffer *segbuf, *n; 1295 __u64 nextnum; 1296 int err; 1297 1298 if (list_empty(&sci->sc_segbufs)) { 1299 segbuf = nilfs_segbuf_new(sci->sc_super); 1300 if (unlikely(!segbuf)) 1301 return -ENOMEM; 1302 list_add(&segbuf->sb_list, &sci->sc_segbufs); 1303 } else 1304 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1305 1306 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, nilfs->ns_pseg_offset, 1307 nilfs); 1308 1309 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1310 nilfs_shift_to_next_segment(nilfs); 1311 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1312 } 1313 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1314 1315 err = nilfs_touch_segusage(nilfs->ns_sufile, segbuf->sb_segnum); 1316 if (unlikely(err)) 1317 return err; 1318 1319 if (nilfs->ns_segnum == nilfs->ns_nextnum) { 1320 /* Start from the head of a new full segment */ 1321 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1322 if (unlikely(err)) 1323 return err; 1324 } else 1325 nextnum = nilfs->ns_nextnum; 1326 1327 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1328 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1329 1330 /* truncating segment buffers */ 1331 list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs, 1332 sb_list) { 1333 list_del_init(&segbuf->sb_list); 1334 nilfs_segbuf_free(segbuf); 1335 } 1336 return 0; 1337 } 1338 1339 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1340 struct the_nilfs *nilfs, int nadd) 1341 { 1342 struct nilfs_segment_buffer *segbuf, *prev, *n; 1343 struct inode *sufile = nilfs->ns_sufile; 1344 __u64 nextnextnum; 1345 LIST_HEAD(list); 1346 int err, ret, i; 1347 1348 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1349 /* 1350 * Since the segment specified with nextnum might be allocated during 1351 * the previous construction, the buffer including its segusage may 1352 * not be dirty. The following call ensures that the buffer is dirty 1353 * and will pin the buffer on memory until the sufile is written. 1354 */ 1355 err = nilfs_touch_segusage(sufile, prev->sb_nextnum); 1356 if (unlikely(err)) 1357 return err; 1358 1359 for (i = 0; i < nadd; i++) { 1360 /* extend segment info */ 1361 err = -ENOMEM; 1362 segbuf = nilfs_segbuf_new(sci->sc_super); 1363 if (unlikely(!segbuf)) 1364 goto failed; 1365 1366 /* map this buffer to region of segment on-disk */ 1367 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1368 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1369 1370 /* allocate the next next full segment */ 1371 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1372 if (unlikely(err)) 1373 goto failed_segbuf; 1374 1375 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1376 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1377 1378 list_add_tail(&segbuf->sb_list, &list); 1379 prev = segbuf; 1380 } 1381 list_splice(&list, sci->sc_segbufs.prev); 1382 return 0; 1383 1384 failed_segbuf: 1385 nilfs_segbuf_free(segbuf); 1386 failed: 1387 list_for_each_entry_safe(segbuf, n, &list, sb_list) { 1388 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1389 WARN_ON(ret); /* never fails */ 1390 list_del_init(&segbuf->sb_list); 1391 nilfs_segbuf_free(segbuf); 1392 } 1393 return err; 1394 } 1395 1396 static void nilfs_segctor_free_incomplete_segments(struct nilfs_sc_info *sci, 1397 struct the_nilfs *nilfs) 1398 { 1399 struct nilfs_segment_buffer *segbuf; 1400 int ret, done = 0; 1401 1402 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1403 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1404 ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum); 1405 WARN_ON(ret); /* never fails */ 1406 } 1407 if (segbuf->sb_io_error) { 1408 /* Case 1: The first segment failed */ 1409 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1410 /* Case 1a: Partial segment appended into an existing 1411 segment */ 1412 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1413 segbuf->sb_fseg_end); 1414 else /* Case 1b: New full segment */ 1415 set_nilfs_discontinued(nilfs); 1416 done++; 1417 } 1418 1419 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1420 ret = nilfs_sufile_free(nilfs->ns_sufile, segbuf->sb_nextnum); 1421 WARN_ON(ret); /* never fails */ 1422 if (!done && segbuf->sb_io_error) { 1423 if (segbuf->sb_segnum != nilfs->ns_nextnum) 1424 /* Case 2: extended segment (!= next) failed */ 1425 nilfs_sufile_set_error(nilfs->ns_sufile, 1426 segbuf->sb_segnum); 1427 done++; 1428 } 1429 } 1430 } 1431 1432 static void nilfs_segctor_clear_segment_buffers(struct nilfs_sc_info *sci) 1433 { 1434 struct nilfs_segment_buffer *segbuf; 1435 1436 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) 1437 nilfs_segbuf_clear(segbuf); 1438 sci->sc_super_root = NULL; 1439 } 1440 1441 static void nilfs_segctor_destroy_segment_buffers(struct nilfs_sc_info *sci) 1442 { 1443 struct nilfs_segment_buffer *segbuf; 1444 1445 while (!list_empty(&sci->sc_segbufs)) { 1446 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1447 list_del_init(&segbuf->sb_list); 1448 nilfs_segbuf_free(segbuf); 1449 } 1450 /* sci->sc_curseg = NULL; */ 1451 } 1452 1453 static void nilfs_segctor_end_construction(struct nilfs_sc_info *sci, 1454 struct the_nilfs *nilfs, int err) 1455 { 1456 if (unlikely(err)) { 1457 nilfs_segctor_free_incomplete_segments(sci, nilfs); 1458 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1459 int ret; 1460 1461 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1462 sci->sc_freesegs, 1463 sci->sc_nfreesegs, 1464 NULL); 1465 WARN_ON(ret); /* do not happen */ 1466 } 1467 } 1468 nilfs_segctor_clear_segment_buffers(sci); 1469 } 1470 1471 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1472 struct inode *sufile) 1473 { 1474 struct nilfs_segment_buffer *segbuf; 1475 struct buffer_head *bh_su; 1476 struct nilfs_segment_usage *raw_su; 1477 unsigned long live_blocks; 1478 int ret; 1479 1480 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1481 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum, 1482 &raw_su, &bh_su); 1483 WARN_ON(ret); /* always succeed because bh_su is dirty */ 1484 live_blocks = segbuf->sb_sum.nblocks + 1485 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1486 raw_su->su_lastmod = cpu_to_le64(sci->sc_seg_ctime); 1487 raw_su->su_nblocks = cpu_to_le32(live_blocks); 1488 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, 1489 bh_su); 1490 } 1491 } 1492 1493 static void nilfs_segctor_cancel_segusage(struct nilfs_sc_info *sci, 1494 struct inode *sufile) 1495 { 1496 struct nilfs_segment_buffer *segbuf; 1497 struct buffer_head *bh_su; 1498 struct nilfs_segment_usage *raw_su; 1499 int ret; 1500 1501 segbuf = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1502 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum, 1503 &raw_su, &bh_su); 1504 WARN_ON(ret); /* always succeed because bh_su is dirty */ 1505 raw_su->su_nblocks = cpu_to_le32(segbuf->sb_pseg_start - 1506 segbuf->sb_fseg_start); 1507 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, bh_su); 1508 1509 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1510 ret = nilfs_sufile_get_segment_usage(sufile, segbuf->sb_segnum, 1511 &raw_su, &bh_su); 1512 WARN_ON(ret); /* always succeed */ 1513 raw_su->su_nblocks = 0; 1514 nilfs_sufile_put_segment_usage(sufile, segbuf->sb_segnum, 1515 bh_su); 1516 } 1517 } 1518 1519 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1520 struct nilfs_segment_buffer *last, 1521 struct inode *sufile) 1522 { 1523 struct nilfs_segment_buffer *segbuf = last, *n; 1524 int ret; 1525 1526 list_for_each_entry_safe_continue(segbuf, n, &sci->sc_segbufs, 1527 sb_list) { 1528 list_del_init(&segbuf->sb_list); 1529 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1530 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1531 WARN_ON(ret); 1532 nilfs_segbuf_free(segbuf); 1533 } 1534 } 1535 1536 1537 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1538 struct the_nilfs *nilfs, int mode) 1539 { 1540 struct nilfs_cstage prev_stage = sci->sc_stage; 1541 int err, nadd = 1; 1542 1543 /* Collection retry loop */ 1544 for (;;) { 1545 sci->sc_super_root = NULL; 1546 sci->sc_nblk_this_inc = 0; 1547 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1548 1549 err = nilfs_segctor_reset_segment_buffer(sci); 1550 if (unlikely(err)) 1551 goto failed; 1552 1553 err = nilfs_segctor_collect_blocks(sci, mode); 1554 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1555 if (!err) 1556 break; 1557 1558 if (unlikely(err != -E2BIG)) 1559 goto failed; 1560 1561 /* The current segment is filled up */ 1562 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE) 1563 break; 1564 1565 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1566 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1567 sci->sc_freesegs, 1568 sci->sc_nfreesegs, 1569 NULL); 1570 WARN_ON(err); /* do not happen */ 1571 } 1572 nilfs_segctor_clear_segment_buffers(sci); 1573 1574 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1575 if (unlikely(err)) 1576 return err; 1577 1578 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1579 sci->sc_stage = prev_stage; 1580 } 1581 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1582 return 0; 1583 1584 failed: 1585 return err; 1586 } 1587 1588 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1589 struct buffer_head *new_bh) 1590 { 1591 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1592 1593 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1594 /* The caller must release old_bh */ 1595 } 1596 1597 static int 1598 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1599 struct nilfs_segment_buffer *segbuf, 1600 int mode) 1601 { 1602 struct inode *inode = NULL; 1603 sector_t blocknr; 1604 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1605 unsigned long nblocks = 0, ndatablk = 0; 1606 struct nilfs_sc_operations *sc_op = NULL; 1607 struct nilfs_segsum_pointer ssp; 1608 struct nilfs_finfo *finfo = NULL; 1609 union nilfs_binfo binfo; 1610 struct buffer_head *bh, *bh_org; 1611 ino_t ino = 0; 1612 int err = 0; 1613 1614 if (!nfinfo) 1615 goto out; 1616 1617 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1618 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1619 ssp.offset = sizeof(struct nilfs_segment_summary); 1620 1621 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1622 if (bh == sci->sc_super_root) 1623 break; 1624 if (!finfo) { 1625 finfo = nilfs_segctor_map_segsum_entry( 1626 sci, &ssp, sizeof(*finfo)); 1627 ino = le64_to_cpu(finfo->fi_ino); 1628 nblocks = le32_to_cpu(finfo->fi_nblocks); 1629 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1630 1631 if (buffer_nilfs_node(bh)) 1632 inode = NILFS_BTNC_I(bh->b_page->mapping); 1633 else 1634 inode = NILFS_AS_I(bh->b_page->mapping); 1635 1636 if (mode == SC_LSEG_DSYNC) 1637 sc_op = &nilfs_sc_dsync_ops; 1638 else if (ino == NILFS_DAT_INO) 1639 sc_op = &nilfs_sc_dat_ops; 1640 else /* file blocks */ 1641 sc_op = &nilfs_sc_file_ops; 1642 } 1643 bh_org = bh; 1644 get_bh(bh_org); 1645 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1646 &binfo); 1647 if (bh != bh_org) 1648 nilfs_list_replace_buffer(bh_org, bh); 1649 brelse(bh_org); 1650 if (unlikely(err)) 1651 goto failed_bmap; 1652 1653 if (ndatablk > 0) 1654 sc_op->write_data_binfo(sci, &ssp, &binfo); 1655 else 1656 sc_op->write_node_binfo(sci, &ssp, &binfo); 1657 1658 blocknr++; 1659 if (--nblocks == 0) { 1660 finfo = NULL; 1661 if (--nfinfo == 0) 1662 break; 1663 } else if (ndatablk > 0) 1664 ndatablk--; 1665 } 1666 out: 1667 return 0; 1668 1669 failed_bmap: 1670 err = nilfs_handle_bmap_error(err, __func__, inode, sci->sc_super); 1671 return err; 1672 } 1673 1674 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1675 { 1676 struct nilfs_segment_buffer *segbuf; 1677 int err; 1678 1679 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1680 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1681 if (unlikely(err)) 1682 return err; 1683 nilfs_segbuf_fill_in_segsum(segbuf); 1684 } 1685 return 0; 1686 } 1687 1688 static int 1689 nilfs_copy_replace_page_buffers(struct page *page, struct list_head *out) 1690 { 1691 struct page *clone_page; 1692 struct buffer_head *bh, *head, *bh2; 1693 void *kaddr; 1694 1695 bh = head = page_buffers(page); 1696 1697 clone_page = nilfs_alloc_private_page(bh->b_bdev, bh->b_size, 0); 1698 if (unlikely(!clone_page)) 1699 return -ENOMEM; 1700 1701 bh2 = page_buffers(clone_page); 1702 kaddr = kmap_atomic(page, KM_USER0); 1703 do { 1704 if (list_empty(&bh->b_assoc_buffers)) 1705 continue; 1706 get_bh(bh2); 1707 page_cache_get(clone_page); /* for each bh */ 1708 memcpy(bh2->b_data, kaddr + bh_offset(bh), bh2->b_size); 1709 bh2->b_blocknr = bh->b_blocknr; 1710 list_replace(&bh->b_assoc_buffers, &bh2->b_assoc_buffers); 1711 list_add_tail(&bh->b_assoc_buffers, out); 1712 } while (bh = bh->b_this_page, bh2 = bh2->b_this_page, bh != head); 1713 kunmap_atomic(kaddr, KM_USER0); 1714 1715 if (!TestSetPageWriteback(clone_page)) 1716 inc_zone_page_state(clone_page, NR_WRITEBACK); 1717 unlock_page(clone_page); 1718 1719 return 0; 1720 } 1721 1722 static int nilfs_test_page_to_be_frozen(struct page *page) 1723 { 1724 struct address_space *mapping = page->mapping; 1725 1726 if (!mapping || !mapping->host || S_ISDIR(mapping->host->i_mode)) 1727 return 0; 1728 1729 if (page_mapped(page)) { 1730 ClearPageChecked(page); 1731 return 1; 1732 } 1733 return PageChecked(page); 1734 } 1735 1736 static int nilfs_begin_page_io(struct page *page, struct list_head *out) 1737 { 1738 if (!page || PageWriteback(page)) 1739 /* For split b-tree node pages, this function may be called 1740 twice. We ignore the 2nd or later calls by this check. */ 1741 return 0; 1742 1743 lock_page(page); 1744 clear_page_dirty_for_io(page); 1745 set_page_writeback(page); 1746 unlock_page(page); 1747 1748 if (nilfs_test_page_to_be_frozen(page)) { 1749 int err = nilfs_copy_replace_page_buffers(page, out); 1750 if (unlikely(err)) 1751 return err; 1752 } 1753 return 0; 1754 } 1755 1756 static int nilfs_segctor_prepare_write(struct nilfs_sc_info *sci, 1757 struct page **failed_page) 1758 { 1759 struct nilfs_segment_buffer *segbuf; 1760 struct page *bd_page = NULL, *fs_page = NULL; 1761 struct list_head *list = &sci->sc_copied_buffers; 1762 int err; 1763 1764 *failed_page = NULL; 1765 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1766 struct buffer_head *bh; 1767 1768 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1769 b_assoc_buffers) { 1770 if (bh->b_page != bd_page) { 1771 if (bd_page) { 1772 lock_page(bd_page); 1773 clear_page_dirty_for_io(bd_page); 1774 set_page_writeback(bd_page); 1775 unlock_page(bd_page); 1776 } 1777 bd_page = bh->b_page; 1778 } 1779 } 1780 1781 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1782 b_assoc_buffers) { 1783 if (bh == sci->sc_super_root) { 1784 if (bh->b_page != bd_page) { 1785 lock_page(bd_page); 1786 clear_page_dirty_for_io(bd_page); 1787 set_page_writeback(bd_page); 1788 unlock_page(bd_page); 1789 bd_page = bh->b_page; 1790 } 1791 break; 1792 } 1793 if (bh->b_page != fs_page) { 1794 err = nilfs_begin_page_io(fs_page, list); 1795 if (unlikely(err)) { 1796 *failed_page = fs_page; 1797 goto out; 1798 } 1799 fs_page = bh->b_page; 1800 } 1801 } 1802 } 1803 if (bd_page) { 1804 lock_page(bd_page); 1805 clear_page_dirty_for_io(bd_page); 1806 set_page_writeback(bd_page); 1807 unlock_page(bd_page); 1808 } 1809 err = nilfs_begin_page_io(fs_page, list); 1810 if (unlikely(err)) 1811 *failed_page = fs_page; 1812 out: 1813 return err; 1814 } 1815 1816 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1817 struct backing_dev_info *bdi) 1818 { 1819 struct nilfs_segment_buffer *segbuf; 1820 struct nilfs_write_info wi; 1821 int err, res; 1822 1823 wi.sb = sci->sc_super; 1824 wi.bh_sr = sci->sc_super_root; 1825 wi.bdi = bdi; 1826 1827 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1828 nilfs_segbuf_prepare_write(segbuf, &wi); 1829 err = nilfs_segbuf_write(segbuf, &wi); 1830 1831 res = nilfs_segbuf_wait(segbuf, &wi); 1832 err = err ? : res; 1833 if (err) 1834 return err; 1835 } 1836 return 0; 1837 } 1838 1839 static void __nilfs_end_page_io(struct page *page, int err) 1840 { 1841 if (!err) { 1842 if (!nilfs_page_buffers_clean(page)) 1843 __set_page_dirty_nobuffers(page); 1844 ClearPageError(page); 1845 } else { 1846 __set_page_dirty_nobuffers(page); 1847 SetPageError(page); 1848 } 1849 1850 if (buffer_nilfs_allocated(page_buffers(page))) { 1851 if (TestClearPageWriteback(page)) 1852 dec_zone_page_state(page, NR_WRITEBACK); 1853 } else 1854 end_page_writeback(page); 1855 } 1856 1857 static void nilfs_end_page_io(struct page *page, int err) 1858 { 1859 if (!page) 1860 return; 1861 1862 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) 1863 /* 1864 * For b-tree node pages, this function may be called twice 1865 * or more because they might be split in a segment. 1866 */ 1867 return; 1868 1869 __nilfs_end_page_io(page, err); 1870 } 1871 1872 static void nilfs_clear_copied_buffers(struct list_head *list, int err) 1873 { 1874 struct buffer_head *bh, *head; 1875 struct page *page; 1876 1877 while (!list_empty(list)) { 1878 bh = list_entry(list->next, struct buffer_head, 1879 b_assoc_buffers); 1880 page = bh->b_page; 1881 page_cache_get(page); 1882 head = bh = page_buffers(page); 1883 do { 1884 if (!list_empty(&bh->b_assoc_buffers)) { 1885 list_del_init(&bh->b_assoc_buffers); 1886 if (!err) { 1887 set_buffer_uptodate(bh); 1888 clear_buffer_dirty(bh); 1889 clear_buffer_nilfs_volatile(bh); 1890 } 1891 brelse(bh); /* for b_assoc_buffers */ 1892 } 1893 } while ((bh = bh->b_this_page) != head); 1894 1895 __nilfs_end_page_io(page, err); 1896 page_cache_release(page); 1897 } 1898 } 1899 1900 static void nilfs_segctor_abort_write(struct nilfs_sc_info *sci, 1901 struct page *failed_page, int err) 1902 { 1903 struct nilfs_segment_buffer *segbuf; 1904 struct page *bd_page = NULL, *fs_page = NULL; 1905 1906 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1907 struct buffer_head *bh; 1908 1909 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1910 b_assoc_buffers) { 1911 if (bh->b_page != bd_page) { 1912 if (bd_page) 1913 end_page_writeback(bd_page); 1914 bd_page = bh->b_page; 1915 } 1916 } 1917 1918 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1919 b_assoc_buffers) { 1920 if (bh == sci->sc_super_root) { 1921 if (bh->b_page != bd_page) { 1922 end_page_writeback(bd_page); 1923 bd_page = bh->b_page; 1924 } 1925 break; 1926 } 1927 if (bh->b_page != fs_page) { 1928 nilfs_end_page_io(fs_page, err); 1929 if (fs_page && fs_page == failed_page) 1930 goto done; 1931 fs_page = bh->b_page; 1932 } 1933 } 1934 } 1935 if (bd_page) 1936 end_page_writeback(bd_page); 1937 1938 nilfs_end_page_io(fs_page, err); 1939 done: 1940 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, err); 1941 } 1942 1943 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1944 struct nilfs_segment_buffer *segbuf) 1945 { 1946 nilfs->ns_segnum = segbuf->sb_segnum; 1947 nilfs->ns_nextnum = segbuf->sb_nextnum; 1948 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1949 + segbuf->sb_sum.nblocks; 1950 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1951 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1952 } 1953 1954 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1955 { 1956 struct nilfs_segment_buffer *segbuf; 1957 struct page *bd_page = NULL, *fs_page = NULL; 1958 struct nilfs_sb_info *sbi = sci->sc_sbi; 1959 struct the_nilfs *nilfs = sbi->s_nilfs; 1960 int update_sr = (sci->sc_super_root != NULL); 1961 1962 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1963 struct buffer_head *bh; 1964 1965 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1966 b_assoc_buffers) { 1967 set_buffer_uptodate(bh); 1968 clear_buffer_dirty(bh); 1969 if (bh->b_page != bd_page) { 1970 if (bd_page) 1971 end_page_writeback(bd_page); 1972 bd_page = bh->b_page; 1973 } 1974 } 1975 /* 1976 * We assume that the buffers which belong to the same page 1977 * continue over the buffer list. 1978 * Under this assumption, the last BHs of pages is 1979 * identifiable by the discontinuity of bh->b_page 1980 * (page != fs_page). 1981 * 1982 * For B-tree node blocks, however, this assumption is not 1983 * guaranteed. The cleanup code of B-tree node pages needs 1984 * special care. 1985 */ 1986 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1987 b_assoc_buffers) { 1988 set_buffer_uptodate(bh); 1989 clear_buffer_dirty(bh); 1990 clear_buffer_nilfs_volatile(bh); 1991 if (bh == sci->sc_super_root) { 1992 if (bh->b_page != bd_page) { 1993 end_page_writeback(bd_page); 1994 bd_page = bh->b_page; 1995 } 1996 break; 1997 } 1998 if (bh->b_page != fs_page) { 1999 nilfs_end_page_io(fs_page, 0); 2000 fs_page = bh->b_page; 2001 } 2002 } 2003 2004 if (!NILFS_SEG_SIMPLEX(&segbuf->sb_sum)) { 2005 if (NILFS_SEG_LOGBGN(&segbuf->sb_sum)) { 2006 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 2007 sci->sc_lseg_stime = jiffies; 2008 } 2009 if (NILFS_SEG_LOGEND(&segbuf->sb_sum)) 2010 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 2011 } 2012 } 2013 /* 2014 * Since pages may continue over multiple segment buffers, 2015 * end of the last page must be checked outside of the loop. 2016 */ 2017 if (bd_page) 2018 end_page_writeback(bd_page); 2019 2020 nilfs_end_page_io(fs_page, 0); 2021 2022 nilfs_clear_copied_buffers(&sci->sc_copied_buffers, 0); 2023 2024 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 2025 2026 if (nilfs_doing_gc()) { 2027 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 2028 if (update_sr) 2029 nilfs_commit_gcdat_inode(nilfs); 2030 } else 2031 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 2032 2033 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 2034 2035 segbuf = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 2036 nilfs_set_next_segment(nilfs, segbuf); 2037 2038 if (update_sr) { 2039 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 2040 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 2041 sbi->s_super->s_dirt = 1; 2042 2043 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 2044 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2045 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 2046 } else 2047 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 2048 } 2049 2050 static int nilfs_segctor_check_in_files(struct nilfs_sc_info *sci, 2051 struct nilfs_sb_info *sbi) 2052 { 2053 struct nilfs_inode_info *ii, *n; 2054 __u64 cno = sbi->s_nilfs->ns_cno; 2055 2056 spin_lock(&sbi->s_inode_lock); 2057 retry: 2058 list_for_each_entry_safe(ii, n, &sbi->s_dirty_files, i_dirty) { 2059 if (!ii->i_bh) { 2060 struct buffer_head *ibh; 2061 int err; 2062 2063 spin_unlock(&sbi->s_inode_lock); 2064 err = nilfs_ifile_get_inode_block( 2065 sbi->s_ifile, ii->vfs_inode.i_ino, &ibh); 2066 if (unlikely(err)) { 2067 nilfs_warning(sbi->s_super, __func__, 2068 "failed to get inode block.\n"); 2069 return err; 2070 } 2071 nilfs_mdt_mark_buffer_dirty(ibh); 2072 nilfs_mdt_mark_dirty(sbi->s_ifile); 2073 spin_lock(&sbi->s_inode_lock); 2074 if (likely(!ii->i_bh)) 2075 ii->i_bh = ibh; 2076 else 2077 brelse(ibh); 2078 goto retry; 2079 } 2080 ii->i_cno = cno; 2081 2082 clear_bit(NILFS_I_QUEUED, &ii->i_state); 2083 set_bit(NILFS_I_BUSY, &ii->i_state); 2084 list_del(&ii->i_dirty); 2085 list_add_tail(&ii->i_dirty, &sci->sc_dirty_files); 2086 } 2087 spin_unlock(&sbi->s_inode_lock); 2088 2089 NILFS_I(sbi->s_ifile)->i_cno = cno; 2090 2091 return 0; 2092 } 2093 2094 static void nilfs_segctor_check_out_files(struct nilfs_sc_info *sci, 2095 struct nilfs_sb_info *sbi) 2096 { 2097 struct nilfs_transaction_info *ti = current->journal_info; 2098 struct nilfs_inode_info *ii, *n; 2099 __u64 cno = sbi->s_nilfs->ns_cno; 2100 2101 spin_lock(&sbi->s_inode_lock); 2102 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 2103 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 2104 test_bit(NILFS_I_DIRTY, &ii->i_state)) { 2105 /* The current checkpoint number (=nilfs->ns_cno) is 2106 changed between check-in and check-out only if the 2107 super root is written out. So, we can update i_cno 2108 for the inodes that remain in the dirty list. */ 2109 ii->i_cno = cno; 2110 continue; 2111 } 2112 clear_bit(NILFS_I_BUSY, &ii->i_state); 2113 brelse(ii->i_bh); 2114 ii->i_bh = NULL; 2115 list_del(&ii->i_dirty); 2116 list_add_tail(&ii->i_dirty, &ti->ti_garbage); 2117 } 2118 spin_unlock(&sbi->s_inode_lock); 2119 } 2120 2121 /* 2122 * Main procedure of segment constructor 2123 */ 2124 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 2125 { 2126 struct nilfs_sb_info *sbi = sci->sc_sbi; 2127 struct the_nilfs *nilfs = sbi->s_nilfs; 2128 struct page *failed_page; 2129 int err, has_sr = 0; 2130 2131 sci->sc_stage.scnt = NILFS_ST_INIT; 2132 2133 err = nilfs_segctor_check_in_files(sci, sbi); 2134 if (unlikely(err)) 2135 goto out; 2136 2137 if (nilfs_test_metadata_dirty(sbi)) 2138 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2139 2140 if (nilfs_segctor_clean(sci)) 2141 goto out; 2142 2143 do { 2144 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 2145 2146 err = nilfs_segctor_begin_construction(sci, nilfs); 2147 if (unlikely(err)) 2148 goto out; 2149 2150 /* Update time stamp */ 2151 sci->sc_seg_ctime = get_seconds(); 2152 2153 err = nilfs_segctor_collect(sci, nilfs, mode); 2154 if (unlikely(err)) 2155 goto failed; 2156 2157 has_sr = (sci->sc_super_root != NULL); 2158 2159 /* Avoid empty segment */ 2160 if (sci->sc_stage.scnt == NILFS_ST_DONE && 2161 NILFS_SEG_EMPTY(&sci->sc_curseg->sb_sum)) { 2162 nilfs_segctor_end_construction(sci, nilfs, 1); 2163 goto out; 2164 } 2165 2166 err = nilfs_segctor_assign(sci, mode); 2167 if (unlikely(err)) 2168 goto failed; 2169 2170 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2171 nilfs_segctor_fill_in_file_bmap(sci, sbi->s_ifile); 2172 2173 if (has_sr) { 2174 err = nilfs_segctor_fill_in_checkpoint(sci); 2175 if (unlikely(err)) 2176 goto failed_to_make_up; 2177 2178 nilfs_segctor_fill_in_super_root(sci, nilfs); 2179 } 2180 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 2181 2182 /* Write partial segments */ 2183 err = nilfs_segctor_prepare_write(sci, &failed_page); 2184 if (unlikely(err)) 2185 goto failed_to_write; 2186 2187 nilfs_segctor_fill_in_checksums(sci, nilfs->ns_crc_seed); 2188 2189 err = nilfs_segctor_write(sci, nilfs->ns_bdi); 2190 if (unlikely(err)) 2191 goto failed_to_write; 2192 2193 nilfs_segctor_complete_write(sci); 2194 2195 /* Commit segments */ 2196 if (has_sr) 2197 nilfs_segctor_clear_metadata_dirty(sci); 2198 2199 nilfs_segctor_end_construction(sci, nilfs, 0); 2200 2201 } while (sci->sc_stage.scnt != NILFS_ST_DONE); 2202 2203 out: 2204 nilfs_segctor_destroy_segment_buffers(sci); 2205 nilfs_segctor_check_out_files(sci, sbi); 2206 return err; 2207 2208 failed_to_write: 2209 nilfs_segctor_abort_write(sci, failed_page, err); 2210 nilfs_segctor_cancel_segusage(sci, nilfs->ns_sufile); 2211 2212 failed_to_make_up: 2213 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2214 nilfs_redirty_inodes(&sci->sc_dirty_files); 2215 2216 failed: 2217 if (nilfs_doing_gc()) 2218 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2219 nilfs_segctor_end_construction(sci, nilfs, err); 2220 goto out; 2221 } 2222 2223 /** 2224 * nilfs_secgtor_start_timer - set timer of background write 2225 * @sci: nilfs_sc_info 2226 * 2227 * If the timer has already been set, it ignores the new request. 2228 * This function MUST be called within a section locking the segment 2229 * semaphore. 2230 */ 2231 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2232 { 2233 spin_lock(&sci->sc_state_lock); 2234 if (sci->sc_timer && !(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2235 sci->sc_timer->expires = jiffies + sci->sc_interval; 2236 add_timer(sci->sc_timer); 2237 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2238 } 2239 spin_unlock(&sci->sc_state_lock); 2240 } 2241 2242 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2243 { 2244 spin_lock(&sci->sc_state_lock); 2245 if (!(sci->sc_flush_request & (1 << bn))) { 2246 unsigned long prev_req = sci->sc_flush_request; 2247 2248 sci->sc_flush_request |= (1 << bn); 2249 if (!prev_req) 2250 wake_up(&sci->sc_wait_daemon); 2251 } 2252 spin_unlock(&sci->sc_state_lock); 2253 } 2254 2255 /** 2256 * nilfs_flush_segment - trigger a segment construction for resource control 2257 * @sb: super block 2258 * @ino: inode number of the file to be flushed out. 2259 */ 2260 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2261 { 2262 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2263 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2264 2265 if (!sci || nilfs_doing_construction()) 2266 return; 2267 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2268 /* assign bit 0 to data files */ 2269 } 2270 2271 struct nilfs_segctor_wait_request { 2272 wait_queue_t wq; 2273 __u32 seq; 2274 int err; 2275 atomic_t done; 2276 }; 2277 2278 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2279 { 2280 struct nilfs_segctor_wait_request wait_req; 2281 int err = 0; 2282 2283 spin_lock(&sci->sc_state_lock); 2284 init_wait(&wait_req.wq); 2285 wait_req.err = 0; 2286 atomic_set(&wait_req.done, 0); 2287 wait_req.seq = ++sci->sc_seq_request; 2288 spin_unlock(&sci->sc_state_lock); 2289 2290 init_waitqueue_entry(&wait_req.wq, current); 2291 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2292 set_current_state(TASK_INTERRUPTIBLE); 2293 wake_up(&sci->sc_wait_daemon); 2294 2295 for (;;) { 2296 if (atomic_read(&wait_req.done)) { 2297 err = wait_req.err; 2298 break; 2299 } 2300 if (!signal_pending(current)) { 2301 schedule(); 2302 continue; 2303 } 2304 err = -ERESTARTSYS; 2305 break; 2306 } 2307 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2308 return err; 2309 } 2310 2311 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2312 { 2313 struct nilfs_segctor_wait_request *wrq, *n; 2314 unsigned long flags; 2315 2316 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2317 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list, 2318 wq.task_list) { 2319 if (!atomic_read(&wrq->done) && 2320 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { 2321 wrq->err = err; 2322 atomic_set(&wrq->done, 1); 2323 } 2324 if (atomic_read(&wrq->done)) { 2325 wrq->wq.func(&wrq->wq, 2326 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 2327 0, NULL); 2328 } 2329 } 2330 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); 2331 } 2332 2333 /** 2334 * nilfs_construct_segment - construct a logical segment 2335 * @sb: super block 2336 * 2337 * Return Value: On success, 0 is retured. On errors, one of the following 2338 * negative error code is returned. 2339 * 2340 * %-EROFS - Read only filesystem. 2341 * 2342 * %-EIO - I/O error 2343 * 2344 * %-ENOSPC - No space left on device (only in a panic state). 2345 * 2346 * %-ERESTARTSYS - Interrupted. 2347 * 2348 * %-ENOMEM - Insufficient memory available. 2349 */ 2350 int nilfs_construct_segment(struct super_block *sb) 2351 { 2352 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2353 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2354 struct nilfs_transaction_info *ti; 2355 int err; 2356 2357 if (!sci) 2358 return -EROFS; 2359 2360 /* A call inside transactions causes a deadlock. */ 2361 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); 2362 2363 err = nilfs_segctor_sync(sci); 2364 return err; 2365 } 2366 2367 /** 2368 * nilfs_construct_dsync_segment - construct a data-only logical segment 2369 * @sb: super block 2370 * @inode: inode whose data blocks should be written out 2371 * @start: start byte offset 2372 * @end: end byte offset (inclusive) 2373 * 2374 * Return Value: On success, 0 is retured. On errors, one of the following 2375 * negative error code is returned. 2376 * 2377 * %-EROFS - Read only filesystem. 2378 * 2379 * %-EIO - I/O error 2380 * 2381 * %-ENOSPC - No space left on device (only in a panic state). 2382 * 2383 * %-ERESTARTSYS - Interrupted. 2384 * 2385 * %-ENOMEM - Insufficient memory available. 2386 */ 2387 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 2388 loff_t start, loff_t end) 2389 { 2390 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2391 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2392 struct nilfs_inode_info *ii; 2393 struct nilfs_transaction_info ti; 2394 int err = 0; 2395 2396 if (!sci) 2397 return -EROFS; 2398 2399 nilfs_transaction_lock(sbi, &ti, 0); 2400 2401 ii = NILFS_I(inode); 2402 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) || 2403 nilfs_test_opt(sbi, STRICT_ORDER) || 2404 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2405 nilfs_discontinued(sbi->s_nilfs)) { 2406 nilfs_transaction_unlock(sbi); 2407 err = nilfs_segctor_sync(sci); 2408 return err; 2409 } 2410 2411 spin_lock(&sbi->s_inode_lock); 2412 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && 2413 !test_bit(NILFS_I_BUSY, &ii->i_state)) { 2414 spin_unlock(&sbi->s_inode_lock); 2415 nilfs_transaction_unlock(sbi); 2416 return 0; 2417 } 2418 spin_unlock(&sbi->s_inode_lock); 2419 sci->sc_dsync_inode = ii; 2420 sci->sc_dsync_start = start; 2421 sci->sc_dsync_end = end; 2422 2423 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); 2424 2425 nilfs_transaction_unlock(sbi); 2426 return err; 2427 } 2428 2429 struct nilfs_segctor_req { 2430 int mode; 2431 __u32 seq_accepted; 2432 int sc_err; /* construction failure */ 2433 int sb_err; /* super block writeback failure */ 2434 }; 2435 2436 #define FLUSH_FILE_BIT (0x1) /* data file only */ 2437 #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */ 2438 2439 static void nilfs_segctor_accept(struct nilfs_sc_info *sci, 2440 struct nilfs_segctor_req *req) 2441 { 2442 req->sc_err = req->sb_err = 0; 2443 spin_lock(&sci->sc_state_lock); 2444 req->seq_accepted = sci->sc_seq_request; 2445 spin_unlock(&sci->sc_state_lock); 2446 2447 if (sci->sc_timer) 2448 del_timer_sync(sci->sc_timer); 2449 } 2450 2451 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, 2452 struct nilfs_segctor_req *req) 2453 { 2454 /* Clear requests (even when the construction failed) */ 2455 spin_lock(&sci->sc_state_lock); 2456 2457 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; 2458 2459 if (req->mode == SC_LSEG_SR) { 2460 sci->sc_seq_done = req->seq_accepted; 2461 nilfs_segctor_wakeup(sci, req->sc_err ? : req->sb_err); 2462 sci->sc_flush_request = 0; 2463 } else if (req->mode == SC_FLUSH_FILE) 2464 sci->sc_flush_request &= ~FLUSH_FILE_BIT; 2465 else if (req->mode == SC_FLUSH_DAT) 2466 sci->sc_flush_request &= ~FLUSH_DAT_BIT; 2467 2468 spin_unlock(&sci->sc_state_lock); 2469 } 2470 2471 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, 2472 struct nilfs_segctor_req *req) 2473 { 2474 struct nilfs_sb_info *sbi = sci->sc_sbi; 2475 struct the_nilfs *nilfs = sbi->s_nilfs; 2476 int err = 0; 2477 2478 if (nilfs_discontinued(nilfs)) 2479 req->mode = SC_LSEG_SR; 2480 if (!nilfs_segctor_confirm(sci)) { 2481 err = nilfs_segctor_do_construct(sci, req->mode); 2482 req->sc_err = err; 2483 } 2484 if (likely(!err)) { 2485 if (req->mode != SC_FLUSH_DAT) 2486 atomic_set(&nilfs->ns_ndirtyblks, 0); 2487 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && 2488 nilfs_discontinued(nilfs)) { 2489 down_write(&nilfs->ns_sem); 2490 req->sb_err = nilfs_commit_super(sbi, 0); 2491 up_write(&nilfs->ns_sem); 2492 } 2493 } 2494 return err; 2495 } 2496 2497 static void nilfs_construction_timeout(unsigned long data) 2498 { 2499 struct task_struct *p = (struct task_struct *)data; 2500 wake_up_process(p); 2501 } 2502 2503 static void 2504 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) 2505 { 2506 struct nilfs_inode_info *ii, *n; 2507 2508 list_for_each_entry_safe(ii, n, head, i_dirty) { 2509 if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) 2510 continue; 2511 hlist_del_init(&ii->vfs_inode.i_hash); 2512 list_del_init(&ii->i_dirty); 2513 nilfs_clear_gcinode(&ii->vfs_inode); 2514 } 2515 } 2516 2517 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, 2518 void **kbufs) 2519 { 2520 struct nilfs_sb_info *sbi = NILFS_SB(sb); 2521 struct nilfs_sc_info *sci = NILFS_SC(sbi); 2522 struct the_nilfs *nilfs = sbi->s_nilfs; 2523 struct nilfs_transaction_info ti; 2524 struct nilfs_segctor_req req = { .mode = SC_LSEG_SR }; 2525 int err; 2526 2527 if (unlikely(!sci)) 2528 return -EROFS; 2529 2530 nilfs_transaction_lock(sbi, &ti, 1); 2531 2532 err = nilfs_init_gcdat_inode(nilfs); 2533 if (unlikely(err)) 2534 goto out_unlock; 2535 2536 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs); 2537 if (unlikely(err)) 2538 goto out_unlock; 2539 2540 sci->sc_freesegs = kbufs[4]; 2541 sci->sc_nfreesegs = argv[4].v_nmembs; 2542 list_splice_init(&nilfs->ns_gc_inodes, sci->sc_gc_inodes.prev); 2543 2544 for (;;) { 2545 nilfs_segctor_accept(sci, &req); 2546 err = nilfs_segctor_construct(sci, &req); 2547 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); 2548 nilfs_segctor_notify(sci, &req); 2549 2550 if (likely(!err)) 2551 break; 2552 2553 nilfs_warning(sb, __func__, 2554 "segment construction failed. (err=%d)", err); 2555 set_current_state(TASK_INTERRUPTIBLE); 2556 schedule_timeout(sci->sc_interval); 2557 } 2558 2559 out_unlock: 2560 sci->sc_freesegs = NULL; 2561 sci->sc_nfreesegs = 0; 2562 nilfs_clear_gcdat_inode(nilfs); 2563 nilfs_transaction_unlock(sbi); 2564 return err; 2565 } 2566 2567 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2568 { 2569 struct nilfs_sb_info *sbi = sci->sc_sbi; 2570 struct nilfs_transaction_info ti; 2571 struct nilfs_segctor_req req = { .mode = mode }; 2572 2573 nilfs_transaction_lock(sbi, &ti, 0); 2574 2575 nilfs_segctor_accept(sci, &req); 2576 nilfs_segctor_construct(sci, &req); 2577 nilfs_segctor_notify(sci, &req); 2578 2579 /* 2580 * Unclosed segment should be retried. We do this using sc_timer. 2581 * Timeout of sc_timer will invoke complete construction which leads 2582 * to close the current logical segment. 2583 */ 2584 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2585 nilfs_segctor_start_timer(sci); 2586 2587 nilfs_transaction_unlock(sbi); 2588 } 2589 2590 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2591 { 2592 int mode = 0; 2593 int err; 2594 2595 spin_lock(&sci->sc_state_lock); 2596 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2597 SC_FLUSH_DAT : SC_FLUSH_FILE; 2598 spin_unlock(&sci->sc_state_lock); 2599 2600 if (mode) { 2601 err = nilfs_segctor_do_construct(sci, mode); 2602 2603 spin_lock(&sci->sc_state_lock); 2604 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2605 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2606 spin_unlock(&sci->sc_state_lock); 2607 } 2608 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2609 } 2610 2611 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2612 { 2613 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2614 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2615 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2616 return SC_FLUSH_FILE; 2617 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2618 return SC_FLUSH_DAT; 2619 } 2620 return SC_LSEG_SR; 2621 } 2622 2623 /** 2624 * nilfs_segctor_thread - main loop of the segment constructor thread. 2625 * @arg: pointer to a struct nilfs_sc_info. 2626 * 2627 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2628 * to execute segment constructions. 2629 */ 2630 static int nilfs_segctor_thread(void *arg) 2631 { 2632 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2633 struct timer_list timer; 2634 int timeout = 0; 2635 2636 init_timer(&timer); 2637 timer.data = (unsigned long)current; 2638 timer.function = nilfs_construction_timeout; 2639 sci->sc_timer = &timer; 2640 2641 /* start sync. */ 2642 sci->sc_task = current; 2643 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2644 printk(KERN_INFO 2645 "segctord starting. Construction interval = %lu seconds, " 2646 "CP frequency < %lu seconds\n", 2647 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2648 2649 spin_lock(&sci->sc_state_lock); 2650 loop: 2651 for (;;) { 2652 int mode; 2653 2654 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2655 goto end_thread; 2656 2657 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2658 mode = SC_LSEG_SR; 2659 else if (!sci->sc_flush_request) 2660 break; 2661 else 2662 mode = nilfs_segctor_flush_mode(sci); 2663 2664 spin_unlock(&sci->sc_state_lock); 2665 nilfs_segctor_thread_construct(sci, mode); 2666 spin_lock(&sci->sc_state_lock); 2667 timeout = 0; 2668 } 2669 2670 2671 if (freezing(current)) { 2672 spin_unlock(&sci->sc_state_lock); 2673 refrigerator(); 2674 spin_lock(&sci->sc_state_lock); 2675 } else { 2676 DEFINE_WAIT(wait); 2677 int should_sleep = 1; 2678 2679 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2680 TASK_INTERRUPTIBLE); 2681 2682 if (sci->sc_seq_request != sci->sc_seq_done) 2683 should_sleep = 0; 2684 else if (sci->sc_flush_request) 2685 should_sleep = 0; 2686 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2687 should_sleep = time_before(jiffies, 2688 sci->sc_timer->expires); 2689 2690 if (should_sleep) { 2691 spin_unlock(&sci->sc_state_lock); 2692 schedule(); 2693 spin_lock(&sci->sc_state_lock); 2694 } 2695 finish_wait(&sci->sc_wait_daemon, &wait); 2696 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2697 time_after_eq(jiffies, sci->sc_timer->expires)); 2698 } 2699 goto loop; 2700 2701 end_thread: 2702 spin_unlock(&sci->sc_state_lock); 2703 del_timer_sync(sci->sc_timer); 2704 sci->sc_timer = NULL; 2705 2706 /* end sync. */ 2707 sci->sc_task = NULL; 2708 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2709 return 0; 2710 } 2711 2712 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2713 { 2714 struct task_struct *t; 2715 2716 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2717 if (IS_ERR(t)) { 2718 int err = PTR_ERR(t); 2719 2720 printk(KERN_ERR "NILFS: error %d creating segctord thread\n", 2721 err); 2722 return err; 2723 } 2724 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2725 return 0; 2726 } 2727 2728 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2729 { 2730 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2731 2732 while (sci->sc_task) { 2733 wake_up(&sci->sc_wait_daemon); 2734 spin_unlock(&sci->sc_state_lock); 2735 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2736 spin_lock(&sci->sc_state_lock); 2737 } 2738 } 2739 2740 static int nilfs_segctor_init(struct nilfs_sc_info *sci) 2741 { 2742 sci->sc_seq_done = sci->sc_seq_request; 2743 2744 return nilfs_segctor_start_thread(sci); 2745 } 2746 2747 /* 2748 * Setup & clean-up functions 2749 */ 2750 static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi) 2751 { 2752 struct nilfs_sc_info *sci; 2753 2754 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2755 if (!sci) 2756 return NULL; 2757 2758 sci->sc_sbi = sbi; 2759 sci->sc_super = sbi->s_super; 2760 2761 init_waitqueue_head(&sci->sc_wait_request); 2762 init_waitqueue_head(&sci->sc_wait_daemon); 2763 init_waitqueue_head(&sci->sc_wait_task); 2764 spin_lock_init(&sci->sc_state_lock); 2765 INIT_LIST_HEAD(&sci->sc_dirty_files); 2766 INIT_LIST_HEAD(&sci->sc_segbufs); 2767 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2768 INIT_LIST_HEAD(&sci->sc_copied_buffers); 2769 2770 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2771 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2772 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2773 2774 if (sbi->s_interval) 2775 sci->sc_interval = sbi->s_interval; 2776 if (sbi->s_watermark) 2777 sci->sc_watermark = sbi->s_watermark; 2778 return sci; 2779 } 2780 2781 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2782 { 2783 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2784 2785 /* The segctord thread was stopped and its timer was removed. 2786 But some tasks remain. */ 2787 do { 2788 struct nilfs_sb_info *sbi = sci->sc_sbi; 2789 struct nilfs_transaction_info ti; 2790 struct nilfs_segctor_req req = { .mode = SC_LSEG_SR }; 2791 2792 nilfs_transaction_lock(sbi, &ti, 0); 2793 nilfs_segctor_accept(sci, &req); 2794 ret = nilfs_segctor_construct(sci, &req); 2795 nilfs_segctor_notify(sci, &req); 2796 nilfs_transaction_unlock(sbi); 2797 2798 } while (ret && retrycount-- > 0); 2799 } 2800 2801 /** 2802 * nilfs_segctor_destroy - destroy the segment constructor. 2803 * @sci: nilfs_sc_info 2804 * 2805 * nilfs_segctor_destroy() kills the segctord thread and frees 2806 * the nilfs_sc_info struct. 2807 * Caller must hold the segment semaphore. 2808 */ 2809 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2810 { 2811 struct nilfs_sb_info *sbi = sci->sc_sbi; 2812 int flag; 2813 2814 up_write(&sbi->s_nilfs->ns_segctor_sem); 2815 2816 spin_lock(&sci->sc_state_lock); 2817 nilfs_segctor_kill_thread(sci); 2818 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2819 || sci->sc_seq_request != sci->sc_seq_done); 2820 spin_unlock(&sci->sc_state_lock); 2821 2822 if (flag || nilfs_segctor_confirm(sci)) 2823 nilfs_segctor_write_out(sci); 2824 2825 WARN_ON(!list_empty(&sci->sc_copied_buffers)); 2826 2827 if (!list_empty(&sci->sc_dirty_files)) { 2828 nilfs_warning(sbi->s_super, __func__, 2829 "dirty file(s) after the final construction\n"); 2830 nilfs_dispose_list(sbi, &sci->sc_dirty_files, 1); 2831 } 2832 2833 WARN_ON(!list_empty(&sci->sc_segbufs)); 2834 2835 down_write(&sbi->s_nilfs->ns_segctor_sem); 2836 2837 kfree(sci); 2838 } 2839 2840 /** 2841 * nilfs_attach_segment_constructor - attach a segment constructor 2842 * @sbi: nilfs_sb_info 2843 * 2844 * nilfs_attach_segment_constructor() allocates a struct nilfs_sc_info, 2845 * initilizes it, and starts the segment constructor. 2846 * 2847 * Return Value: On success, 0 is returned. On error, one of the following 2848 * negative error code is returned. 2849 * 2850 * %-ENOMEM - Insufficient memory available. 2851 */ 2852 int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi) 2853 { 2854 struct the_nilfs *nilfs = sbi->s_nilfs; 2855 int err; 2856 2857 /* Each field of nilfs_segctor is cleared through the initialization 2858 of super-block info */ 2859 sbi->s_sc_info = nilfs_segctor_new(sbi); 2860 if (!sbi->s_sc_info) 2861 return -ENOMEM; 2862 2863 nilfs_attach_writer(nilfs, sbi); 2864 err = nilfs_segctor_init(NILFS_SC(sbi)); 2865 if (err) { 2866 nilfs_detach_writer(nilfs, sbi); 2867 kfree(sbi->s_sc_info); 2868 sbi->s_sc_info = NULL; 2869 } 2870 return err; 2871 } 2872 2873 /** 2874 * nilfs_detach_segment_constructor - destroy the segment constructor 2875 * @sbi: nilfs_sb_info 2876 * 2877 * nilfs_detach_segment_constructor() kills the segment constructor daemon, 2878 * frees the struct nilfs_sc_info, and destroy the dirty file list. 2879 */ 2880 void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi) 2881 { 2882 struct the_nilfs *nilfs = sbi->s_nilfs; 2883 LIST_HEAD(garbage_list); 2884 2885 down_write(&nilfs->ns_segctor_sem); 2886 if (NILFS_SC(sbi)) { 2887 nilfs_segctor_destroy(NILFS_SC(sbi)); 2888 sbi->s_sc_info = NULL; 2889 } 2890 2891 /* Force to free the list of dirty files */ 2892 spin_lock(&sbi->s_inode_lock); 2893 if (!list_empty(&sbi->s_dirty_files)) { 2894 list_splice_init(&sbi->s_dirty_files, &garbage_list); 2895 nilfs_warning(sbi->s_super, __func__, 2896 "Non empty dirty list after the last " 2897 "segment construction\n"); 2898 } 2899 spin_unlock(&sbi->s_inode_lock); 2900 up_write(&nilfs->ns_segctor_sem); 2901 2902 nilfs_dispose_list(sbi, &garbage_list, 1); 2903 nilfs_detach_writer(nilfs, sbi); 2904 } 2905