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