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 * Written by Ryusuke Konishi. 17 * 18 */ 19 20 #include <linux/pagemap.h> 21 #include <linux/buffer_head.h> 22 #include <linux/writeback.h> 23 #include <linux/bitops.h> 24 #include <linux/bio.h> 25 #include <linux/completion.h> 26 #include <linux/blkdev.h> 27 #include <linux/backing-dev.h> 28 #include <linux/freezer.h> 29 #include <linux/kthread.h> 30 #include <linux/crc32.h> 31 #include <linux/pagevec.h> 32 #include <linux/slab.h> 33 #include <linux/sched/signal.h> 34 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 /* 51 * Upper limit of the number of segments 52 * appended in collection retry loop 53 */ 54 55 /* Construction mode */ 56 enum { 57 SC_LSEG_SR = 1, /* Make a logical segment having a super root */ 58 SC_LSEG_DSYNC, /* 59 * Flush data blocks of a given file and make 60 * a logical segment without a super root. 61 */ 62 SC_FLUSH_FILE, /* 63 * Flush data files, leads to segment writes without 64 * creating a checkpoint. 65 */ 66 SC_FLUSH_DAT, /* 67 * Flush DAT file. This also creates segments 68 * without a checkpoint. 69 */ 70 }; 71 72 /* Stage numbers of dirty block collection */ 73 enum { 74 NILFS_ST_INIT = 0, 75 NILFS_ST_GC, /* Collecting dirty blocks for GC */ 76 NILFS_ST_FILE, 77 NILFS_ST_IFILE, 78 NILFS_ST_CPFILE, 79 NILFS_ST_SUFILE, 80 NILFS_ST_DAT, 81 NILFS_ST_SR, /* Super root */ 82 NILFS_ST_DSYNC, /* Data sync blocks */ 83 NILFS_ST_DONE, 84 }; 85 86 #define CREATE_TRACE_POINTS 87 #include <trace/events/nilfs2.h> 88 89 /* 90 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are 91 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of 92 * the variable must use them because transition of stage count must involve 93 * trace events (trace_nilfs2_collection_stage_transition). 94 * 95 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't 96 * produce tracepoint events. It is provided just for making the intention 97 * clear. 98 */ 99 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci) 100 { 101 sci->sc_stage.scnt++; 102 trace_nilfs2_collection_stage_transition(sci); 103 } 104 105 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt) 106 { 107 sci->sc_stage.scnt = next_scnt; 108 trace_nilfs2_collection_stage_transition(sci); 109 } 110 111 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci) 112 { 113 return sci->sc_stage.scnt; 114 } 115 116 /* State flags of collection */ 117 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ 118 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ 119 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */ 120 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED) 121 122 /* Operations depending on the construction mode and file type */ 123 struct nilfs_sc_operations { 124 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, 125 struct inode *); 126 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, 127 struct inode *); 128 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, 129 struct inode *); 130 void (*write_data_binfo)(struct nilfs_sc_info *, 131 struct nilfs_segsum_pointer *, 132 union nilfs_binfo *); 133 void (*write_node_binfo)(struct nilfs_sc_info *, 134 struct nilfs_segsum_pointer *, 135 union nilfs_binfo *); 136 }; 137 138 /* 139 * Other definitions 140 */ 141 static void nilfs_segctor_start_timer(struct nilfs_sc_info *); 142 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); 143 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); 144 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int); 145 146 #define nilfs_cnt32_gt(a, b) \ 147 (typecheck(__u32, a) && typecheck(__u32, b) && \ 148 ((__s32)(b) - (__s32)(a) < 0)) 149 #define nilfs_cnt32_ge(a, b) \ 150 (typecheck(__u32, a) && typecheck(__u32, b) && \ 151 ((__s32)(a) - (__s32)(b) >= 0)) 152 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a) 153 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a) 154 155 static int nilfs_prepare_segment_lock(struct super_block *sb, 156 struct nilfs_transaction_info *ti) 157 { 158 struct nilfs_transaction_info *cur_ti = current->journal_info; 159 void *save = NULL; 160 161 if (cur_ti) { 162 if (cur_ti->ti_magic == NILFS_TI_MAGIC) 163 return ++cur_ti->ti_count; 164 165 /* 166 * If journal_info field is occupied by other FS, 167 * it is saved and will be restored on 168 * nilfs_transaction_commit(). 169 */ 170 nilfs_msg(sb, KERN_WARNING, "journal info from a different FS"); 171 save = current->journal_info; 172 } 173 if (!ti) { 174 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); 175 if (!ti) 176 return -ENOMEM; 177 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; 178 } else { 179 ti->ti_flags = 0; 180 } 181 ti->ti_count = 0; 182 ti->ti_save = save; 183 ti->ti_magic = NILFS_TI_MAGIC; 184 current->journal_info = ti; 185 return 0; 186 } 187 188 /** 189 * nilfs_transaction_begin - start indivisible file operations. 190 * @sb: super block 191 * @ti: nilfs_transaction_info 192 * @vacancy_check: flags for vacancy rate checks 193 * 194 * nilfs_transaction_begin() acquires a reader/writer semaphore, called 195 * the segment semaphore, to make a segment construction and write tasks 196 * exclusive. The function is used with nilfs_transaction_commit() in pairs. 197 * The region enclosed by these two functions can be nested. To avoid a 198 * deadlock, the semaphore is only acquired or released in the outermost call. 199 * 200 * This function allocates a nilfs_transaction_info struct to keep context 201 * information on it. It is initialized and hooked onto the current task in 202 * the outermost call. If a pre-allocated struct is given to @ti, it is used 203 * instead; otherwise a new struct is assigned from a slab. 204 * 205 * When @vacancy_check flag is set, this function will check the amount of 206 * free space, and will wait for the GC to reclaim disk space if low capacity. 207 * 208 * Return Value: On success, 0 is returned. On error, one of the following 209 * negative error code is returned. 210 * 211 * %-ENOMEM - Insufficient memory available. 212 * 213 * %-ENOSPC - No space left on device 214 */ 215 int nilfs_transaction_begin(struct super_block *sb, 216 struct nilfs_transaction_info *ti, 217 int vacancy_check) 218 { 219 struct the_nilfs *nilfs; 220 int ret = nilfs_prepare_segment_lock(sb, ti); 221 struct nilfs_transaction_info *trace_ti; 222 223 if (unlikely(ret < 0)) 224 return ret; 225 if (ret > 0) { 226 trace_ti = current->journal_info; 227 228 trace_nilfs2_transaction_transition(sb, trace_ti, 229 trace_ti->ti_count, trace_ti->ti_flags, 230 TRACE_NILFS2_TRANSACTION_BEGIN); 231 return 0; 232 } 233 234 sb_start_intwrite(sb); 235 236 nilfs = sb->s_fs_info; 237 down_read(&nilfs->ns_segctor_sem); 238 if (vacancy_check && nilfs_near_disk_full(nilfs)) { 239 up_read(&nilfs->ns_segctor_sem); 240 ret = -ENOSPC; 241 goto failed; 242 } 243 244 trace_ti = current->journal_info; 245 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count, 246 trace_ti->ti_flags, 247 TRACE_NILFS2_TRANSACTION_BEGIN); 248 return 0; 249 250 failed: 251 ti = current->journal_info; 252 current->journal_info = ti->ti_save; 253 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 254 kmem_cache_free(nilfs_transaction_cachep, ti); 255 sb_end_intwrite(sb); 256 return ret; 257 } 258 259 /** 260 * nilfs_transaction_commit - commit indivisible file operations. 261 * @sb: super block 262 * 263 * nilfs_transaction_commit() releases the read semaphore which is 264 * acquired by nilfs_transaction_begin(). This is only performed 265 * in outermost call of this function. If a commit flag is set, 266 * nilfs_transaction_commit() sets a timer to start the segment 267 * constructor. If a sync flag is set, it starts construction 268 * directly. 269 */ 270 int nilfs_transaction_commit(struct super_block *sb) 271 { 272 struct nilfs_transaction_info *ti = current->journal_info; 273 struct the_nilfs *nilfs = sb->s_fs_info; 274 int err = 0; 275 276 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 277 ti->ti_flags |= NILFS_TI_COMMIT; 278 if (ti->ti_count > 0) { 279 ti->ti_count--; 280 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 281 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT); 282 return 0; 283 } 284 if (nilfs->ns_writer) { 285 struct nilfs_sc_info *sci = nilfs->ns_writer; 286 287 if (ti->ti_flags & NILFS_TI_COMMIT) 288 nilfs_segctor_start_timer(sci); 289 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark) 290 nilfs_segctor_do_flush(sci, 0); 291 } 292 up_read(&nilfs->ns_segctor_sem); 293 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 294 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT); 295 296 current->journal_info = ti->ti_save; 297 298 if (ti->ti_flags & NILFS_TI_SYNC) 299 err = nilfs_construct_segment(sb); 300 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 301 kmem_cache_free(nilfs_transaction_cachep, ti); 302 sb_end_intwrite(sb); 303 return err; 304 } 305 306 void nilfs_transaction_abort(struct super_block *sb) 307 { 308 struct nilfs_transaction_info *ti = current->journal_info; 309 struct the_nilfs *nilfs = sb->s_fs_info; 310 311 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 312 if (ti->ti_count > 0) { 313 ti->ti_count--; 314 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 315 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT); 316 return; 317 } 318 up_read(&nilfs->ns_segctor_sem); 319 320 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 321 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT); 322 323 current->journal_info = ti->ti_save; 324 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 325 kmem_cache_free(nilfs_transaction_cachep, ti); 326 sb_end_intwrite(sb); 327 } 328 329 void nilfs_relax_pressure_in_lock(struct super_block *sb) 330 { 331 struct the_nilfs *nilfs = sb->s_fs_info; 332 struct nilfs_sc_info *sci = nilfs->ns_writer; 333 334 if (!sci || !sci->sc_flush_request) 335 return; 336 337 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 338 up_read(&nilfs->ns_segctor_sem); 339 340 down_write(&nilfs->ns_segctor_sem); 341 if (sci->sc_flush_request && 342 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { 343 struct nilfs_transaction_info *ti = current->journal_info; 344 345 ti->ti_flags |= NILFS_TI_WRITER; 346 nilfs_segctor_do_immediate_flush(sci); 347 ti->ti_flags &= ~NILFS_TI_WRITER; 348 } 349 downgrade_write(&nilfs->ns_segctor_sem); 350 } 351 352 static void nilfs_transaction_lock(struct super_block *sb, 353 struct nilfs_transaction_info *ti, 354 int gcflag) 355 { 356 struct nilfs_transaction_info *cur_ti = current->journal_info; 357 struct the_nilfs *nilfs = sb->s_fs_info; 358 struct nilfs_sc_info *sci = nilfs->ns_writer; 359 360 WARN_ON(cur_ti); 361 ti->ti_flags = NILFS_TI_WRITER; 362 ti->ti_count = 0; 363 ti->ti_save = cur_ti; 364 ti->ti_magic = NILFS_TI_MAGIC; 365 current->journal_info = ti; 366 367 for (;;) { 368 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 369 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK); 370 371 down_write(&nilfs->ns_segctor_sem); 372 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) 373 break; 374 375 nilfs_segctor_do_immediate_flush(sci); 376 377 up_write(&nilfs->ns_segctor_sem); 378 cond_resched(); 379 } 380 if (gcflag) 381 ti->ti_flags |= NILFS_TI_GC; 382 383 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 384 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK); 385 } 386 387 static void nilfs_transaction_unlock(struct super_block *sb) 388 { 389 struct nilfs_transaction_info *ti = current->journal_info; 390 struct the_nilfs *nilfs = sb->s_fs_info; 391 392 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 393 BUG_ON(ti->ti_count > 0); 394 395 up_write(&nilfs->ns_segctor_sem); 396 current->journal_info = ti->ti_save; 397 398 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 399 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK); 400 } 401 402 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, 403 struct nilfs_segsum_pointer *ssp, 404 unsigned int bytes) 405 { 406 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 407 unsigned int blocksize = sci->sc_super->s_blocksize; 408 void *p; 409 410 if (unlikely(ssp->offset + bytes > blocksize)) { 411 ssp->offset = 0; 412 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, 413 &segbuf->sb_segsum_buffers)); 414 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); 415 } 416 p = ssp->bh->b_data + ssp->offset; 417 ssp->offset += bytes; 418 return p; 419 } 420 421 /** 422 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer 423 * @sci: nilfs_sc_info 424 */ 425 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) 426 { 427 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 428 struct buffer_head *sumbh; 429 unsigned int sumbytes; 430 unsigned int flags = 0; 431 int err; 432 433 if (nilfs_doing_gc()) 434 flags = NILFS_SS_GC; 435 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno); 436 if (unlikely(err)) 437 return err; 438 439 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 440 sumbytes = segbuf->sb_sum.sumbytes; 441 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; 442 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; 443 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 444 return 0; 445 } 446 447 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) 448 { 449 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 450 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) 451 return -E2BIG; /* 452 * The current segment is filled up 453 * (internal code) 454 */ 455 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); 456 return nilfs_segctor_reset_segment_buffer(sci); 457 } 458 459 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) 460 { 461 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 462 int err; 463 464 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { 465 err = nilfs_segctor_feed_segment(sci); 466 if (err) 467 return err; 468 segbuf = sci->sc_curseg; 469 } 470 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root); 471 if (likely(!err)) 472 segbuf->sb_sum.flags |= NILFS_SS_SR; 473 return err; 474 } 475 476 /* 477 * Functions for making segment summary and payloads 478 */ 479 static int nilfs_segctor_segsum_block_required( 480 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, 481 unsigned int binfo_size) 482 { 483 unsigned int blocksize = sci->sc_super->s_blocksize; 484 /* Size of finfo and binfo is enough small against blocksize */ 485 486 return ssp->offset + binfo_size + 487 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > 488 blocksize; 489 } 490 491 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, 492 struct inode *inode) 493 { 494 sci->sc_curseg->sb_sum.nfinfo++; 495 sci->sc_binfo_ptr = sci->sc_finfo_ptr; 496 nilfs_segctor_map_segsum_entry( 497 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); 498 499 if (NILFS_I(inode)->i_root && 500 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 501 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 502 /* skip finfo */ 503 } 504 505 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, 506 struct inode *inode) 507 { 508 struct nilfs_finfo *finfo; 509 struct nilfs_inode_info *ii; 510 struct nilfs_segment_buffer *segbuf; 511 __u64 cno; 512 513 if (sci->sc_blk_cnt == 0) 514 return; 515 516 ii = NILFS_I(inode); 517 518 if (test_bit(NILFS_I_GCINODE, &ii->i_state)) 519 cno = ii->i_cno; 520 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) 521 cno = 0; 522 else 523 cno = sci->sc_cno; 524 525 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, 526 sizeof(*finfo)); 527 finfo->fi_ino = cpu_to_le64(inode->i_ino); 528 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); 529 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); 530 finfo->fi_cno = cpu_to_le64(cno); 531 532 segbuf = sci->sc_curseg; 533 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + 534 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); 535 sci->sc_finfo_ptr = sci->sc_binfo_ptr; 536 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 537 } 538 539 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, 540 struct buffer_head *bh, 541 struct inode *inode, 542 unsigned int binfo_size) 543 { 544 struct nilfs_segment_buffer *segbuf; 545 int required, err = 0; 546 547 retry: 548 segbuf = sci->sc_curseg; 549 required = nilfs_segctor_segsum_block_required( 550 sci, &sci->sc_binfo_ptr, binfo_size); 551 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { 552 nilfs_segctor_end_finfo(sci, inode); 553 err = nilfs_segctor_feed_segment(sci); 554 if (err) 555 return err; 556 goto retry; 557 } 558 if (unlikely(required)) { 559 err = nilfs_segbuf_extend_segsum(segbuf); 560 if (unlikely(err)) 561 goto failed; 562 } 563 if (sci->sc_blk_cnt == 0) 564 nilfs_segctor_begin_finfo(sci, inode); 565 566 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); 567 /* Substitution to vblocknr is delayed until update_blocknr() */ 568 nilfs_segbuf_add_file_buffer(segbuf, bh); 569 sci->sc_blk_cnt++; 570 failed: 571 return err; 572 } 573 574 /* 575 * Callback functions that enumerate, mark, and collect dirty blocks 576 */ 577 static int nilfs_collect_file_data(struct nilfs_sc_info *sci, 578 struct buffer_head *bh, struct inode *inode) 579 { 580 int err; 581 582 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 583 if (err < 0) 584 return err; 585 586 err = nilfs_segctor_add_file_block(sci, bh, inode, 587 sizeof(struct nilfs_binfo_v)); 588 if (!err) 589 sci->sc_datablk_cnt++; 590 return err; 591 } 592 593 static int nilfs_collect_file_node(struct nilfs_sc_info *sci, 594 struct buffer_head *bh, 595 struct inode *inode) 596 { 597 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 598 } 599 600 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, 601 struct buffer_head *bh, 602 struct inode *inode) 603 { 604 WARN_ON(!buffer_dirty(bh)); 605 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 606 } 607 608 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, 609 struct nilfs_segsum_pointer *ssp, 610 union nilfs_binfo *binfo) 611 { 612 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( 613 sci, ssp, sizeof(*binfo_v)); 614 *binfo_v = binfo->bi_v; 615 } 616 617 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, 618 struct nilfs_segsum_pointer *ssp, 619 union nilfs_binfo *binfo) 620 { 621 __le64 *vblocknr = nilfs_segctor_map_segsum_entry( 622 sci, ssp, sizeof(*vblocknr)); 623 *vblocknr = binfo->bi_v.bi_vblocknr; 624 } 625 626 static const struct nilfs_sc_operations nilfs_sc_file_ops = { 627 .collect_data = nilfs_collect_file_data, 628 .collect_node = nilfs_collect_file_node, 629 .collect_bmap = nilfs_collect_file_bmap, 630 .write_data_binfo = nilfs_write_file_data_binfo, 631 .write_node_binfo = nilfs_write_file_node_binfo, 632 }; 633 634 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, 635 struct buffer_head *bh, struct inode *inode) 636 { 637 int err; 638 639 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 640 if (err < 0) 641 return err; 642 643 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 644 if (!err) 645 sci->sc_datablk_cnt++; 646 return err; 647 } 648 649 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, 650 struct buffer_head *bh, struct inode *inode) 651 { 652 WARN_ON(!buffer_dirty(bh)); 653 return nilfs_segctor_add_file_block(sci, bh, inode, 654 sizeof(struct nilfs_binfo_dat)); 655 } 656 657 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, 658 struct nilfs_segsum_pointer *ssp, 659 union nilfs_binfo *binfo) 660 { 661 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, 662 sizeof(*blkoff)); 663 *blkoff = binfo->bi_dat.bi_blkoff; 664 } 665 666 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, 667 struct nilfs_segsum_pointer *ssp, 668 union nilfs_binfo *binfo) 669 { 670 struct nilfs_binfo_dat *binfo_dat = 671 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); 672 *binfo_dat = binfo->bi_dat; 673 } 674 675 static const struct nilfs_sc_operations nilfs_sc_dat_ops = { 676 .collect_data = nilfs_collect_dat_data, 677 .collect_node = nilfs_collect_file_node, 678 .collect_bmap = nilfs_collect_dat_bmap, 679 .write_data_binfo = nilfs_write_dat_data_binfo, 680 .write_node_binfo = nilfs_write_dat_node_binfo, 681 }; 682 683 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = { 684 .collect_data = nilfs_collect_file_data, 685 .collect_node = NULL, 686 .collect_bmap = NULL, 687 .write_data_binfo = nilfs_write_file_data_binfo, 688 .write_node_binfo = NULL, 689 }; 690 691 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, 692 struct list_head *listp, 693 size_t nlimit, 694 loff_t start, loff_t end) 695 { 696 struct address_space *mapping = inode->i_mapping; 697 struct pagevec pvec; 698 pgoff_t index = 0, last = ULONG_MAX; 699 size_t ndirties = 0; 700 int i; 701 702 if (unlikely(start != 0 || end != LLONG_MAX)) { 703 /* 704 * A valid range is given for sync-ing data pages. The 705 * range is rounded to per-page; extra dirty buffers 706 * may be included if blocksize < pagesize. 707 */ 708 index = start >> PAGE_SHIFT; 709 last = end >> PAGE_SHIFT; 710 } 711 pagevec_init(&pvec, 0); 712 repeat: 713 if (unlikely(index > last) || 714 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 715 min_t(pgoff_t, last - index, 716 PAGEVEC_SIZE - 1) + 1)) 717 return ndirties; 718 719 for (i = 0; i < pagevec_count(&pvec); i++) { 720 struct buffer_head *bh, *head; 721 struct page *page = pvec.pages[i]; 722 723 if (unlikely(page->index > last)) 724 break; 725 726 lock_page(page); 727 if (!page_has_buffers(page)) 728 create_empty_buffers(page, i_blocksize(inode), 0); 729 unlock_page(page); 730 731 bh = head = page_buffers(page); 732 do { 733 if (!buffer_dirty(bh) || buffer_async_write(bh)) 734 continue; 735 get_bh(bh); 736 list_add_tail(&bh->b_assoc_buffers, listp); 737 ndirties++; 738 if (unlikely(ndirties >= nlimit)) { 739 pagevec_release(&pvec); 740 cond_resched(); 741 return ndirties; 742 } 743 } while (bh = bh->b_this_page, bh != head); 744 } 745 pagevec_release(&pvec); 746 cond_resched(); 747 goto repeat; 748 } 749 750 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 751 struct list_head *listp) 752 { 753 struct nilfs_inode_info *ii = NILFS_I(inode); 754 struct address_space *mapping = &ii->i_btnode_cache; 755 struct pagevec pvec; 756 struct buffer_head *bh, *head; 757 unsigned int i; 758 pgoff_t index = 0; 759 760 pagevec_init(&pvec, 0); 761 762 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 763 PAGEVEC_SIZE)) { 764 for (i = 0; i < pagevec_count(&pvec); i++) { 765 bh = head = page_buffers(pvec.pages[i]); 766 do { 767 if (buffer_dirty(bh) && 768 !buffer_async_write(bh)) { 769 get_bh(bh); 770 list_add_tail(&bh->b_assoc_buffers, 771 listp); 772 } 773 bh = bh->b_this_page; 774 } while (bh != head); 775 } 776 pagevec_release(&pvec); 777 cond_resched(); 778 } 779 } 780 781 static void nilfs_dispose_list(struct the_nilfs *nilfs, 782 struct list_head *head, int force) 783 { 784 struct nilfs_inode_info *ii, *n; 785 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 786 unsigned int nv = 0; 787 788 while (!list_empty(head)) { 789 spin_lock(&nilfs->ns_inode_lock); 790 list_for_each_entry_safe(ii, n, head, i_dirty) { 791 list_del_init(&ii->i_dirty); 792 if (force) { 793 if (unlikely(ii->i_bh)) { 794 brelse(ii->i_bh); 795 ii->i_bh = NULL; 796 } 797 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 798 set_bit(NILFS_I_QUEUED, &ii->i_state); 799 list_add_tail(&ii->i_dirty, 800 &nilfs->ns_dirty_files); 801 continue; 802 } 803 ivec[nv++] = ii; 804 if (nv == SC_N_INODEVEC) 805 break; 806 } 807 spin_unlock(&nilfs->ns_inode_lock); 808 809 for (pii = ivec; nv > 0; pii++, nv--) 810 iput(&(*pii)->vfs_inode); 811 } 812 } 813 814 static void nilfs_iput_work_func(struct work_struct *work) 815 { 816 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info, 817 sc_iput_work); 818 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 819 820 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0); 821 } 822 823 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs, 824 struct nilfs_root *root) 825 { 826 int ret = 0; 827 828 if (nilfs_mdt_fetch_dirty(root->ifile)) 829 ret++; 830 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 831 ret++; 832 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 833 ret++; 834 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat)) 835 ret++; 836 return ret; 837 } 838 839 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 840 { 841 return list_empty(&sci->sc_dirty_files) && 842 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 843 sci->sc_nfreesegs == 0 && 844 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 845 } 846 847 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 848 { 849 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 850 int ret = 0; 851 852 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 853 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 854 855 spin_lock(&nilfs->ns_inode_lock); 856 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci)) 857 ret++; 858 859 spin_unlock(&nilfs->ns_inode_lock); 860 return ret; 861 } 862 863 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 864 { 865 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 866 867 nilfs_mdt_clear_dirty(sci->sc_root->ifile); 868 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 869 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 870 nilfs_mdt_clear_dirty(nilfs->ns_dat); 871 } 872 873 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 874 { 875 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 876 struct buffer_head *bh_cp; 877 struct nilfs_checkpoint *raw_cp; 878 int err; 879 880 /* XXX: this interface will be changed */ 881 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 882 &raw_cp, &bh_cp); 883 if (likely(!err)) { 884 /* 885 * The following code is duplicated with cpfile. But, it is 886 * needed to collect the checkpoint even if it was not newly 887 * created. 888 */ 889 mark_buffer_dirty(bh_cp); 890 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 891 nilfs_cpfile_put_checkpoint( 892 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 893 } else 894 WARN_ON(err == -EINVAL || err == -ENOENT); 895 896 return err; 897 } 898 899 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 900 { 901 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 902 struct buffer_head *bh_cp; 903 struct nilfs_checkpoint *raw_cp; 904 int err; 905 906 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 907 &raw_cp, &bh_cp); 908 if (unlikely(err)) { 909 WARN_ON(err == -EINVAL || err == -ENOENT); 910 goto failed_ibh; 911 } 912 raw_cp->cp_snapshot_list.ssl_next = 0; 913 raw_cp->cp_snapshot_list.ssl_prev = 0; 914 raw_cp->cp_inodes_count = 915 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count)); 916 raw_cp->cp_blocks_count = 917 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count)); 918 raw_cp->cp_nblk_inc = 919 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 920 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 921 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 922 923 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 924 nilfs_checkpoint_clear_minor(raw_cp); 925 else 926 nilfs_checkpoint_set_minor(raw_cp); 927 928 nilfs_write_inode_common(sci->sc_root->ifile, 929 &raw_cp->cp_ifile_inode, 1); 930 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 931 return 0; 932 933 failed_ibh: 934 return err; 935 } 936 937 static void nilfs_fill_in_file_bmap(struct inode *ifile, 938 struct nilfs_inode_info *ii) 939 940 { 941 struct buffer_head *ibh; 942 struct nilfs_inode *raw_inode; 943 944 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 945 ibh = ii->i_bh; 946 BUG_ON(!ibh); 947 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 948 ibh); 949 nilfs_bmap_write(ii->i_bmap, raw_inode); 950 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 951 } 952 } 953 954 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci) 955 { 956 struct nilfs_inode_info *ii; 957 958 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 959 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii); 960 set_bit(NILFS_I_COLLECTED, &ii->i_state); 961 } 962 } 963 964 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 965 struct the_nilfs *nilfs) 966 { 967 struct buffer_head *bh_sr; 968 struct nilfs_super_root *raw_sr; 969 unsigned int isz, srsz; 970 971 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root; 972 raw_sr = (struct nilfs_super_root *)bh_sr->b_data; 973 isz = nilfs->ns_inode_size; 974 srsz = NILFS_SR_BYTES(isz); 975 976 raw_sr->sr_bytes = cpu_to_le16(srsz); 977 raw_sr->sr_nongc_ctime 978 = cpu_to_le64(nilfs_doing_gc() ? 979 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 980 raw_sr->sr_flags = 0; 981 982 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr + 983 NILFS_SR_DAT_OFFSET(isz), 1); 984 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr + 985 NILFS_SR_CPFILE_OFFSET(isz), 1); 986 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr + 987 NILFS_SR_SUFILE_OFFSET(isz), 1); 988 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz); 989 } 990 991 static void nilfs_redirty_inodes(struct list_head *head) 992 { 993 struct nilfs_inode_info *ii; 994 995 list_for_each_entry(ii, head, i_dirty) { 996 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 997 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 998 } 999 } 1000 1001 static void nilfs_drop_collected_inodes(struct list_head *head) 1002 { 1003 struct nilfs_inode_info *ii; 1004 1005 list_for_each_entry(ii, head, i_dirty) { 1006 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 1007 continue; 1008 1009 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state); 1010 set_bit(NILFS_I_UPDATED, &ii->i_state); 1011 } 1012 } 1013 1014 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 1015 struct inode *inode, 1016 struct list_head *listp, 1017 int (*collect)(struct nilfs_sc_info *, 1018 struct buffer_head *, 1019 struct inode *)) 1020 { 1021 struct buffer_head *bh, *n; 1022 int err = 0; 1023 1024 if (collect) { 1025 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 1026 list_del_init(&bh->b_assoc_buffers); 1027 err = collect(sci, bh, inode); 1028 brelse(bh); 1029 if (unlikely(err)) 1030 goto dispose_buffers; 1031 } 1032 return 0; 1033 } 1034 1035 dispose_buffers: 1036 while (!list_empty(listp)) { 1037 bh = list_first_entry(listp, struct buffer_head, 1038 b_assoc_buffers); 1039 list_del_init(&bh->b_assoc_buffers); 1040 brelse(bh); 1041 } 1042 return err; 1043 } 1044 1045 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 1046 { 1047 /* Remaining number of blocks within segment buffer */ 1048 return sci->sc_segbuf_nblocks - 1049 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 1050 } 1051 1052 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 1053 struct inode *inode, 1054 const struct nilfs_sc_operations *sc_ops) 1055 { 1056 LIST_HEAD(data_buffers); 1057 LIST_HEAD(node_buffers); 1058 int err; 1059 1060 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1061 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1062 1063 n = nilfs_lookup_dirty_data_buffers( 1064 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 1065 if (n > rest) { 1066 err = nilfs_segctor_apply_buffers( 1067 sci, inode, &data_buffers, 1068 sc_ops->collect_data); 1069 BUG_ON(!err); /* always receive -E2BIG or true error */ 1070 goto break_or_fail; 1071 } 1072 } 1073 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 1074 1075 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1076 err = nilfs_segctor_apply_buffers( 1077 sci, inode, &data_buffers, sc_ops->collect_data); 1078 if (unlikely(err)) { 1079 /* dispose node list */ 1080 nilfs_segctor_apply_buffers( 1081 sci, inode, &node_buffers, NULL); 1082 goto break_or_fail; 1083 } 1084 sci->sc_stage.flags |= NILFS_CF_NODE; 1085 } 1086 /* Collect node */ 1087 err = nilfs_segctor_apply_buffers( 1088 sci, inode, &node_buffers, sc_ops->collect_node); 1089 if (unlikely(err)) 1090 goto break_or_fail; 1091 1092 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1093 err = nilfs_segctor_apply_buffers( 1094 sci, inode, &node_buffers, sc_ops->collect_bmap); 1095 if (unlikely(err)) 1096 goto break_or_fail; 1097 1098 nilfs_segctor_end_finfo(sci, inode); 1099 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1100 1101 break_or_fail: 1102 return err; 1103 } 1104 1105 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1106 struct inode *inode) 1107 { 1108 LIST_HEAD(data_buffers); 1109 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1110 int err; 1111 1112 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1113 sci->sc_dsync_start, 1114 sci->sc_dsync_end); 1115 1116 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1117 nilfs_collect_file_data); 1118 if (!err) { 1119 nilfs_segctor_end_finfo(sci, inode); 1120 BUG_ON(n > rest); 1121 /* always receive -E2BIG or true error if n > rest */ 1122 } 1123 return err; 1124 } 1125 1126 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1127 { 1128 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1129 struct list_head *head; 1130 struct nilfs_inode_info *ii; 1131 size_t ndone; 1132 int err = 0; 1133 1134 switch (nilfs_sc_cstage_get(sci)) { 1135 case NILFS_ST_INIT: 1136 /* Pre-processes */ 1137 sci->sc_stage.flags = 0; 1138 1139 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1140 sci->sc_nblk_inc = 0; 1141 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1142 if (mode == SC_LSEG_DSYNC) { 1143 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC); 1144 goto dsync_mode; 1145 } 1146 } 1147 1148 sci->sc_stage.dirty_file_ptr = NULL; 1149 sci->sc_stage.gc_inode_ptr = NULL; 1150 if (mode == SC_FLUSH_DAT) { 1151 nilfs_sc_cstage_set(sci, NILFS_ST_DAT); 1152 goto dat_stage; 1153 } 1154 nilfs_sc_cstage_inc(sci); /* Fall through */ 1155 case NILFS_ST_GC: 1156 if (nilfs_doing_gc()) { 1157 head = &sci->sc_gc_inodes; 1158 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1159 head, i_dirty); 1160 list_for_each_entry_continue(ii, head, i_dirty) { 1161 err = nilfs_segctor_scan_file( 1162 sci, &ii->vfs_inode, 1163 &nilfs_sc_file_ops); 1164 if (unlikely(err)) { 1165 sci->sc_stage.gc_inode_ptr = list_entry( 1166 ii->i_dirty.prev, 1167 struct nilfs_inode_info, 1168 i_dirty); 1169 goto break_or_fail; 1170 } 1171 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1172 } 1173 sci->sc_stage.gc_inode_ptr = NULL; 1174 } 1175 nilfs_sc_cstage_inc(sci); /* Fall through */ 1176 case NILFS_ST_FILE: 1177 head = &sci->sc_dirty_files; 1178 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1179 i_dirty); 1180 list_for_each_entry_continue(ii, head, i_dirty) { 1181 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1182 1183 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1184 &nilfs_sc_file_ops); 1185 if (unlikely(err)) { 1186 sci->sc_stage.dirty_file_ptr = 1187 list_entry(ii->i_dirty.prev, 1188 struct nilfs_inode_info, 1189 i_dirty); 1190 goto break_or_fail; 1191 } 1192 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1193 /* XXX: required ? */ 1194 } 1195 sci->sc_stage.dirty_file_ptr = NULL; 1196 if (mode == SC_FLUSH_FILE) { 1197 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1198 return 0; 1199 } 1200 nilfs_sc_cstage_inc(sci); 1201 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1202 /* Fall through */ 1203 case NILFS_ST_IFILE: 1204 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile, 1205 &nilfs_sc_file_ops); 1206 if (unlikely(err)) 1207 break; 1208 nilfs_sc_cstage_inc(sci); 1209 /* Creating a checkpoint */ 1210 err = nilfs_segctor_create_checkpoint(sci); 1211 if (unlikely(err)) 1212 break; 1213 /* Fall through */ 1214 case NILFS_ST_CPFILE: 1215 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1216 &nilfs_sc_file_ops); 1217 if (unlikely(err)) 1218 break; 1219 nilfs_sc_cstage_inc(sci); /* Fall through */ 1220 case NILFS_ST_SUFILE: 1221 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1222 sci->sc_nfreesegs, &ndone); 1223 if (unlikely(err)) { 1224 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1225 sci->sc_freesegs, ndone, 1226 NULL); 1227 break; 1228 } 1229 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1230 1231 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1232 &nilfs_sc_file_ops); 1233 if (unlikely(err)) 1234 break; 1235 nilfs_sc_cstage_inc(sci); /* Fall through */ 1236 case NILFS_ST_DAT: 1237 dat_stage: 1238 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat, 1239 &nilfs_sc_dat_ops); 1240 if (unlikely(err)) 1241 break; 1242 if (mode == SC_FLUSH_DAT) { 1243 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1244 return 0; 1245 } 1246 nilfs_sc_cstage_inc(sci); /* Fall through */ 1247 case NILFS_ST_SR: 1248 if (mode == SC_LSEG_SR) { 1249 /* Appending a super root */ 1250 err = nilfs_segctor_add_super_root(sci); 1251 if (unlikely(err)) 1252 break; 1253 } 1254 /* End of a logical segment */ 1255 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1256 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1257 return 0; 1258 case NILFS_ST_DSYNC: 1259 dsync_mode: 1260 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1261 ii = sci->sc_dsync_inode; 1262 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1263 break; 1264 1265 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1266 if (unlikely(err)) 1267 break; 1268 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1269 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1270 return 0; 1271 case NILFS_ST_DONE: 1272 return 0; 1273 default: 1274 BUG(); 1275 } 1276 1277 break_or_fail: 1278 return err; 1279 } 1280 1281 /** 1282 * nilfs_segctor_begin_construction - setup segment buffer to make a new log 1283 * @sci: nilfs_sc_info 1284 * @nilfs: nilfs object 1285 */ 1286 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1287 struct the_nilfs *nilfs) 1288 { 1289 struct nilfs_segment_buffer *segbuf, *prev; 1290 __u64 nextnum; 1291 int err, alloc = 0; 1292 1293 segbuf = nilfs_segbuf_new(sci->sc_super); 1294 if (unlikely(!segbuf)) 1295 return -ENOMEM; 1296 1297 if (list_empty(&sci->sc_write_logs)) { 1298 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 1299 nilfs->ns_pseg_offset, nilfs); 1300 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1301 nilfs_shift_to_next_segment(nilfs); 1302 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1303 } 1304 1305 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1306 nextnum = nilfs->ns_nextnum; 1307 1308 if (nilfs->ns_segnum == nilfs->ns_nextnum) 1309 /* Start from the head of a new full segment */ 1310 alloc++; 1311 } else { 1312 /* Continue logs */ 1313 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1314 nilfs_segbuf_map_cont(segbuf, prev); 1315 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq; 1316 nextnum = prev->sb_nextnum; 1317 1318 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1319 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1320 segbuf->sb_sum.seg_seq++; 1321 alloc++; 1322 } 1323 } 1324 1325 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum); 1326 if (err) 1327 goto failed; 1328 1329 if (alloc) { 1330 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1331 if (err) 1332 goto failed; 1333 } 1334 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1335 1336 BUG_ON(!list_empty(&sci->sc_segbufs)); 1337 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs); 1338 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1339 return 0; 1340 1341 failed: 1342 nilfs_segbuf_free(segbuf); 1343 return err; 1344 } 1345 1346 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1347 struct the_nilfs *nilfs, int nadd) 1348 { 1349 struct nilfs_segment_buffer *segbuf, *prev; 1350 struct inode *sufile = nilfs->ns_sufile; 1351 __u64 nextnextnum; 1352 LIST_HEAD(list); 1353 int err, ret, i; 1354 1355 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1356 /* 1357 * Since the segment specified with nextnum might be allocated during 1358 * the previous construction, the buffer including its segusage may 1359 * not be dirty. The following call ensures that the buffer is dirty 1360 * and will pin the buffer on memory until the sufile is written. 1361 */ 1362 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum); 1363 if (unlikely(err)) 1364 return err; 1365 1366 for (i = 0; i < nadd; i++) { 1367 /* extend segment info */ 1368 err = -ENOMEM; 1369 segbuf = nilfs_segbuf_new(sci->sc_super); 1370 if (unlikely(!segbuf)) 1371 goto failed; 1372 1373 /* map this buffer to region of segment on-disk */ 1374 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1375 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1376 1377 /* allocate the next next full segment */ 1378 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1379 if (unlikely(err)) 1380 goto failed_segbuf; 1381 1382 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1383 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1384 1385 list_add_tail(&segbuf->sb_list, &list); 1386 prev = segbuf; 1387 } 1388 list_splice_tail(&list, &sci->sc_segbufs); 1389 return 0; 1390 1391 failed_segbuf: 1392 nilfs_segbuf_free(segbuf); 1393 failed: 1394 list_for_each_entry(segbuf, &list, sb_list) { 1395 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1396 WARN_ON(ret); /* never fails */ 1397 } 1398 nilfs_destroy_logs(&list); 1399 return err; 1400 } 1401 1402 static void nilfs_free_incomplete_logs(struct list_head *logs, 1403 struct the_nilfs *nilfs) 1404 { 1405 struct nilfs_segment_buffer *segbuf, *prev; 1406 struct inode *sufile = nilfs->ns_sufile; 1407 int ret; 1408 1409 segbuf = NILFS_FIRST_SEGBUF(logs); 1410 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1411 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1412 WARN_ON(ret); /* never fails */ 1413 } 1414 if (atomic_read(&segbuf->sb_err)) { 1415 /* Case 1: The first segment failed */ 1416 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1417 /* 1418 * Case 1a: Partial segment appended into an existing 1419 * segment 1420 */ 1421 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1422 segbuf->sb_fseg_end); 1423 else /* Case 1b: New full segment */ 1424 set_nilfs_discontinued(nilfs); 1425 } 1426 1427 prev = segbuf; 1428 list_for_each_entry_continue(segbuf, logs, sb_list) { 1429 if (prev->sb_nextnum != segbuf->sb_nextnum) { 1430 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1431 WARN_ON(ret); /* never fails */ 1432 } 1433 if (atomic_read(&segbuf->sb_err) && 1434 segbuf->sb_segnum != nilfs->ns_nextnum) 1435 /* Case 2: extended segment (!= next) failed */ 1436 nilfs_sufile_set_error(sufile, segbuf->sb_segnum); 1437 prev = segbuf; 1438 } 1439 } 1440 1441 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1442 struct inode *sufile) 1443 { 1444 struct nilfs_segment_buffer *segbuf; 1445 unsigned long live_blocks; 1446 int ret; 1447 1448 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1449 live_blocks = segbuf->sb_sum.nblocks + 1450 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1451 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1452 live_blocks, 1453 sci->sc_seg_ctime); 1454 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1455 } 1456 } 1457 1458 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile) 1459 { 1460 struct nilfs_segment_buffer *segbuf; 1461 int ret; 1462 1463 segbuf = NILFS_FIRST_SEGBUF(logs); 1464 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1465 segbuf->sb_pseg_start - 1466 segbuf->sb_fseg_start, 0); 1467 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1468 1469 list_for_each_entry_continue(segbuf, logs, sb_list) { 1470 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1471 0, 0); 1472 WARN_ON(ret); /* always succeed */ 1473 } 1474 } 1475 1476 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1477 struct nilfs_segment_buffer *last, 1478 struct inode *sufile) 1479 { 1480 struct nilfs_segment_buffer *segbuf = last; 1481 int ret; 1482 1483 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1484 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1485 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1486 WARN_ON(ret); 1487 } 1488 nilfs_truncate_logs(&sci->sc_segbufs, last); 1489 } 1490 1491 1492 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1493 struct the_nilfs *nilfs, int mode) 1494 { 1495 struct nilfs_cstage prev_stage = sci->sc_stage; 1496 int err, nadd = 1; 1497 1498 /* Collection retry loop */ 1499 for (;;) { 1500 sci->sc_nblk_this_inc = 0; 1501 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1502 1503 err = nilfs_segctor_reset_segment_buffer(sci); 1504 if (unlikely(err)) 1505 goto failed; 1506 1507 err = nilfs_segctor_collect_blocks(sci, mode); 1508 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1509 if (!err) 1510 break; 1511 1512 if (unlikely(err != -E2BIG)) 1513 goto failed; 1514 1515 /* The current segment is filled up */ 1516 if (mode != SC_LSEG_SR || 1517 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE) 1518 break; 1519 1520 nilfs_clear_logs(&sci->sc_segbufs); 1521 1522 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1523 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1524 sci->sc_freesegs, 1525 sci->sc_nfreesegs, 1526 NULL); 1527 WARN_ON(err); /* do not happen */ 1528 sci->sc_stage.flags &= ~NILFS_CF_SUFREED; 1529 } 1530 1531 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1532 if (unlikely(err)) 1533 return err; 1534 1535 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1536 sci->sc_stage = prev_stage; 1537 } 1538 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1539 return 0; 1540 1541 failed: 1542 return err; 1543 } 1544 1545 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1546 struct buffer_head *new_bh) 1547 { 1548 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1549 1550 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1551 /* The caller must release old_bh */ 1552 } 1553 1554 static int 1555 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1556 struct nilfs_segment_buffer *segbuf, 1557 int mode) 1558 { 1559 struct inode *inode = NULL; 1560 sector_t blocknr; 1561 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1562 unsigned long nblocks = 0, ndatablk = 0; 1563 const struct nilfs_sc_operations *sc_op = NULL; 1564 struct nilfs_segsum_pointer ssp; 1565 struct nilfs_finfo *finfo = NULL; 1566 union nilfs_binfo binfo; 1567 struct buffer_head *bh, *bh_org; 1568 ino_t ino = 0; 1569 int err = 0; 1570 1571 if (!nfinfo) 1572 goto out; 1573 1574 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1575 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1576 ssp.offset = sizeof(struct nilfs_segment_summary); 1577 1578 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1579 if (bh == segbuf->sb_super_root) 1580 break; 1581 if (!finfo) { 1582 finfo = nilfs_segctor_map_segsum_entry( 1583 sci, &ssp, sizeof(*finfo)); 1584 ino = le64_to_cpu(finfo->fi_ino); 1585 nblocks = le32_to_cpu(finfo->fi_nblocks); 1586 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1587 1588 inode = bh->b_page->mapping->host; 1589 1590 if (mode == SC_LSEG_DSYNC) 1591 sc_op = &nilfs_sc_dsync_ops; 1592 else if (ino == NILFS_DAT_INO) 1593 sc_op = &nilfs_sc_dat_ops; 1594 else /* file blocks */ 1595 sc_op = &nilfs_sc_file_ops; 1596 } 1597 bh_org = bh; 1598 get_bh(bh_org); 1599 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1600 &binfo); 1601 if (bh != bh_org) 1602 nilfs_list_replace_buffer(bh_org, bh); 1603 brelse(bh_org); 1604 if (unlikely(err)) 1605 goto failed_bmap; 1606 1607 if (ndatablk > 0) 1608 sc_op->write_data_binfo(sci, &ssp, &binfo); 1609 else 1610 sc_op->write_node_binfo(sci, &ssp, &binfo); 1611 1612 blocknr++; 1613 if (--nblocks == 0) { 1614 finfo = NULL; 1615 if (--nfinfo == 0) 1616 break; 1617 } else if (ndatablk > 0) 1618 ndatablk--; 1619 } 1620 out: 1621 return 0; 1622 1623 failed_bmap: 1624 return err; 1625 } 1626 1627 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1628 { 1629 struct nilfs_segment_buffer *segbuf; 1630 int err; 1631 1632 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1633 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1634 if (unlikely(err)) 1635 return err; 1636 nilfs_segbuf_fill_in_segsum(segbuf); 1637 } 1638 return 0; 1639 } 1640 1641 static void nilfs_begin_page_io(struct page *page) 1642 { 1643 if (!page || PageWriteback(page)) 1644 /* 1645 * For split b-tree node pages, this function may be called 1646 * twice. We ignore the 2nd or later calls by this check. 1647 */ 1648 return; 1649 1650 lock_page(page); 1651 clear_page_dirty_for_io(page); 1652 set_page_writeback(page); 1653 unlock_page(page); 1654 } 1655 1656 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci) 1657 { 1658 struct nilfs_segment_buffer *segbuf; 1659 struct page *bd_page = NULL, *fs_page = NULL; 1660 1661 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1662 struct buffer_head *bh; 1663 1664 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1665 b_assoc_buffers) { 1666 if (bh->b_page != bd_page) { 1667 if (bd_page) { 1668 lock_page(bd_page); 1669 clear_page_dirty_for_io(bd_page); 1670 set_page_writeback(bd_page); 1671 unlock_page(bd_page); 1672 } 1673 bd_page = bh->b_page; 1674 } 1675 } 1676 1677 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1678 b_assoc_buffers) { 1679 set_buffer_async_write(bh); 1680 if (bh == segbuf->sb_super_root) { 1681 if (bh->b_page != bd_page) { 1682 lock_page(bd_page); 1683 clear_page_dirty_for_io(bd_page); 1684 set_page_writeback(bd_page); 1685 unlock_page(bd_page); 1686 bd_page = bh->b_page; 1687 } 1688 break; 1689 } 1690 if (bh->b_page != fs_page) { 1691 nilfs_begin_page_io(fs_page); 1692 fs_page = bh->b_page; 1693 } 1694 } 1695 } 1696 if (bd_page) { 1697 lock_page(bd_page); 1698 clear_page_dirty_for_io(bd_page); 1699 set_page_writeback(bd_page); 1700 unlock_page(bd_page); 1701 } 1702 nilfs_begin_page_io(fs_page); 1703 } 1704 1705 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1706 struct the_nilfs *nilfs) 1707 { 1708 int ret; 1709 1710 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs); 1711 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs); 1712 return ret; 1713 } 1714 1715 static void nilfs_end_page_io(struct page *page, int err) 1716 { 1717 if (!page) 1718 return; 1719 1720 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) { 1721 /* 1722 * For b-tree node pages, this function may be called twice 1723 * or more because they might be split in a segment. 1724 */ 1725 if (PageDirty(page)) { 1726 /* 1727 * For pages holding split b-tree node buffers, dirty 1728 * flag on the buffers may be cleared discretely. 1729 * In that case, the page is once redirtied for 1730 * remaining buffers, and it must be cancelled if 1731 * all the buffers get cleaned later. 1732 */ 1733 lock_page(page); 1734 if (nilfs_page_buffers_clean(page)) 1735 __nilfs_clear_page_dirty(page); 1736 unlock_page(page); 1737 } 1738 return; 1739 } 1740 1741 if (!err) { 1742 if (!nilfs_page_buffers_clean(page)) 1743 __set_page_dirty_nobuffers(page); 1744 ClearPageError(page); 1745 } else { 1746 __set_page_dirty_nobuffers(page); 1747 SetPageError(page); 1748 } 1749 1750 end_page_writeback(page); 1751 } 1752 1753 static void nilfs_abort_logs(struct list_head *logs, int err) 1754 { 1755 struct nilfs_segment_buffer *segbuf; 1756 struct page *bd_page = NULL, *fs_page = NULL; 1757 struct buffer_head *bh; 1758 1759 if (list_empty(logs)) 1760 return; 1761 1762 list_for_each_entry(segbuf, logs, sb_list) { 1763 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1764 b_assoc_buffers) { 1765 if (bh->b_page != bd_page) { 1766 if (bd_page) 1767 end_page_writeback(bd_page); 1768 bd_page = bh->b_page; 1769 } 1770 } 1771 1772 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1773 b_assoc_buffers) { 1774 clear_buffer_async_write(bh); 1775 if (bh == segbuf->sb_super_root) { 1776 if (bh->b_page != bd_page) { 1777 end_page_writeback(bd_page); 1778 bd_page = bh->b_page; 1779 } 1780 break; 1781 } 1782 if (bh->b_page != fs_page) { 1783 nilfs_end_page_io(fs_page, err); 1784 fs_page = bh->b_page; 1785 } 1786 } 1787 } 1788 if (bd_page) 1789 end_page_writeback(bd_page); 1790 1791 nilfs_end_page_io(fs_page, err); 1792 } 1793 1794 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci, 1795 struct the_nilfs *nilfs, int err) 1796 { 1797 LIST_HEAD(logs); 1798 int ret; 1799 1800 list_splice_tail_init(&sci->sc_write_logs, &logs); 1801 ret = nilfs_wait_on_logs(&logs); 1802 nilfs_abort_logs(&logs, ret ? : err); 1803 1804 list_splice_tail_init(&sci->sc_segbufs, &logs); 1805 nilfs_cancel_segusage(&logs, nilfs->ns_sufile); 1806 nilfs_free_incomplete_logs(&logs, nilfs); 1807 1808 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1809 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1810 sci->sc_freesegs, 1811 sci->sc_nfreesegs, 1812 NULL); 1813 WARN_ON(ret); /* do not happen */ 1814 } 1815 1816 nilfs_destroy_logs(&logs); 1817 } 1818 1819 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1820 struct nilfs_segment_buffer *segbuf) 1821 { 1822 nilfs->ns_segnum = segbuf->sb_segnum; 1823 nilfs->ns_nextnum = segbuf->sb_nextnum; 1824 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1825 + segbuf->sb_sum.nblocks; 1826 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1827 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1828 } 1829 1830 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1831 { 1832 struct nilfs_segment_buffer *segbuf; 1833 struct page *bd_page = NULL, *fs_page = NULL; 1834 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1835 int update_sr = false; 1836 1837 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) { 1838 struct buffer_head *bh; 1839 1840 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1841 b_assoc_buffers) { 1842 set_buffer_uptodate(bh); 1843 clear_buffer_dirty(bh); 1844 if (bh->b_page != bd_page) { 1845 if (bd_page) 1846 end_page_writeback(bd_page); 1847 bd_page = bh->b_page; 1848 } 1849 } 1850 /* 1851 * We assume that the buffers which belong to the same page 1852 * continue over the buffer list. 1853 * Under this assumption, the last BHs of pages is 1854 * identifiable by the discontinuity of bh->b_page 1855 * (page != fs_page). 1856 * 1857 * For B-tree node blocks, however, this assumption is not 1858 * guaranteed. The cleanup code of B-tree node pages needs 1859 * special care. 1860 */ 1861 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1862 b_assoc_buffers) { 1863 const unsigned long set_bits = BIT(BH_Uptodate); 1864 const unsigned long clear_bits = 1865 (BIT(BH_Dirty) | BIT(BH_Async_Write) | 1866 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) | 1867 BIT(BH_NILFS_Redirected)); 1868 1869 set_mask_bits(&bh->b_state, clear_bits, set_bits); 1870 if (bh == segbuf->sb_super_root) { 1871 if (bh->b_page != bd_page) { 1872 end_page_writeback(bd_page); 1873 bd_page = bh->b_page; 1874 } 1875 update_sr = true; 1876 break; 1877 } 1878 if (bh->b_page != fs_page) { 1879 nilfs_end_page_io(fs_page, 0); 1880 fs_page = bh->b_page; 1881 } 1882 } 1883 1884 if (!nilfs_segbuf_simplex(segbuf)) { 1885 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) { 1886 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1887 sci->sc_lseg_stime = jiffies; 1888 } 1889 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND) 1890 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1891 } 1892 } 1893 /* 1894 * Since pages may continue over multiple segment buffers, 1895 * end of the last page must be checked outside of the loop. 1896 */ 1897 if (bd_page) 1898 end_page_writeback(bd_page); 1899 1900 nilfs_end_page_io(fs_page, 0); 1901 1902 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 1903 1904 if (nilfs_doing_gc()) 1905 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 1906 else 1907 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 1908 1909 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 1910 1911 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1912 nilfs_set_next_segment(nilfs, segbuf); 1913 1914 if (update_sr) { 1915 nilfs->ns_flushed_device = 0; 1916 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 1917 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 1918 1919 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 1920 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 1921 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1922 nilfs_segctor_clear_metadata_dirty(sci); 1923 } else 1924 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1925 } 1926 1927 static int nilfs_segctor_wait(struct nilfs_sc_info *sci) 1928 { 1929 int ret; 1930 1931 ret = nilfs_wait_on_logs(&sci->sc_write_logs); 1932 if (!ret) { 1933 nilfs_segctor_complete_write(sci); 1934 nilfs_destroy_logs(&sci->sc_write_logs); 1935 } 1936 return ret; 1937 } 1938 1939 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci, 1940 struct the_nilfs *nilfs) 1941 { 1942 struct nilfs_inode_info *ii, *n; 1943 struct inode *ifile = sci->sc_root->ifile; 1944 1945 spin_lock(&nilfs->ns_inode_lock); 1946 retry: 1947 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) { 1948 if (!ii->i_bh) { 1949 struct buffer_head *ibh; 1950 int err; 1951 1952 spin_unlock(&nilfs->ns_inode_lock); 1953 err = nilfs_ifile_get_inode_block( 1954 ifile, ii->vfs_inode.i_ino, &ibh); 1955 if (unlikely(err)) { 1956 nilfs_msg(sci->sc_super, KERN_WARNING, 1957 "log writer: error %d getting inode block (ino=%lu)", 1958 err, ii->vfs_inode.i_ino); 1959 return err; 1960 } 1961 mark_buffer_dirty(ibh); 1962 nilfs_mdt_mark_dirty(ifile); 1963 spin_lock(&nilfs->ns_inode_lock); 1964 if (likely(!ii->i_bh)) 1965 ii->i_bh = ibh; 1966 else 1967 brelse(ibh); 1968 goto retry; 1969 } 1970 1971 clear_bit(NILFS_I_QUEUED, &ii->i_state); 1972 set_bit(NILFS_I_BUSY, &ii->i_state); 1973 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files); 1974 } 1975 spin_unlock(&nilfs->ns_inode_lock); 1976 1977 return 0; 1978 } 1979 1980 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci, 1981 struct the_nilfs *nilfs) 1982 { 1983 struct nilfs_inode_info *ii, *n; 1984 int during_mount = !(sci->sc_super->s_flags & MS_ACTIVE); 1985 int defer_iput = false; 1986 1987 spin_lock(&nilfs->ns_inode_lock); 1988 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 1989 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 1990 test_bit(NILFS_I_DIRTY, &ii->i_state)) 1991 continue; 1992 1993 clear_bit(NILFS_I_BUSY, &ii->i_state); 1994 brelse(ii->i_bh); 1995 ii->i_bh = NULL; 1996 list_del_init(&ii->i_dirty); 1997 if (!ii->vfs_inode.i_nlink || during_mount) { 1998 /* 1999 * Defer calling iput() to avoid deadlocks if 2000 * i_nlink == 0 or mount is not yet finished. 2001 */ 2002 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue); 2003 defer_iput = true; 2004 } else { 2005 spin_unlock(&nilfs->ns_inode_lock); 2006 iput(&ii->vfs_inode); 2007 spin_lock(&nilfs->ns_inode_lock); 2008 } 2009 } 2010 spin_unlock(&nilfs->ns_inode_lock); 2011 2012 if (defer_iput) 2013 schedule_work(&sci->sc_iput_work); 2014 } 2015 2016 /* 2017 * Main procedure of segment constructor 2018 */ 2019 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 2020 { 2021 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2022 int err; 2023 2024 nilfs_sc_cstage_set(sci, NILFS_ST_INIT); 2025 sci->sc_cno = nilfs->ns_cno; 2026 2027 err = nilfs_segctor_collect_dirty_files(sci, nilfs); 2028 if (unlikely(err)) 2029 goto out; 2030 2031 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 2032 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2033 2034 if (nilfs_segctor_clean(sci)) 2035 goto out; 2036 2037 do { 2038 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 2039 2040 err = nilfs_segctor_begin_construction(sci, nilfs); 2041 if (unlikely(err)) 2042 goto out; 2043 2044 /* Update time stamp */ 2045 sci->sc_seg_ctime = get_seconds(); 2046 2047 err = nilfs_segctor_collect(sci, nilfs, mode); 2048 if (unlikely(err)) 2049 goto failed; 2050 2051 /* Avoid empty segment */ 2052 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE && 2053 nilfs_segbuf_empty(sci->sc_curseg)) { 2054 nilfs_segctor_abort_construction(sci, nilfs, 1); 2055 goto out; 2056 } 2057 2058 err = nilfs_segctor_assign(sci, mode); 2059 if (unlikely(err)) 2060 goto failed; 2061 2062 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2063 nilfs_segctor_fill_in_file_bmap(sci); 2064 2065 if (mode == SC_LSEG_SR && 2066 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) { 2067 err = nilfs_segctor_fill_in_checkpoint(sci); 2068 if (unlikely(err)) 2069 goto failed_to_write; 2070 2071 nilfs_segctor_fill_in_super_root(sci, nilfs); 2072 } 2073 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 2074 2075 /* Write partial segments */ 2076 nilfs_segctor_prepare_write(sci); 2077 2078 nilfs_add_checksums_on_logs(&sci->sc_segbufs, 2079 nilfs->ns_crc_seed); 2080 2081 err = nilfs_segctor_write(sci, nilfs); 2082 if (unlikely(err)) 2083 goto failed_to_write; 2084 2085 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE || 2086 nilfs->ns_blocksize_bits != PAGE_SHIFT) { 2087 /* 2088 * At this point, we avoid double buffering 2089 * for blocksize < pagesize because page dirty 2090 * flag is turned off during write and dirty 2091 * buffers are not properly collected for 2092 * pages crossing over segments. 2093 */ 2094 err = nilfs_segctor_wait(sci); 2095 if (err) 2096 goto failed_to_write; 2097 } 2098 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE); 2099 2100 out: 2101 nilfs_segctor_drop_written_files(sci, nilfs); 2102 return err; 2103 2104 failed_to_write: 2105 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2106 nilfs_redirty_inodes(&sci->sc_dirty_files); 2107 2108 failed: 2109 if (nilfs_doing_gc()) 2110 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2111 nilfs_segctor_abort_construction(sci, nilfs, err); 2112 goto out; 2113 } 2114 2115 /** 2116 * nilfs_segctor_start_timer - set timer of background write 2117 * @sci: nilfs_sc_info 2118 * 2119 * If the timer has already been set, it ignores the new request. 2120 * This function MUST be called within a section locking the segment 2121 * semaphore. 2122 */ 2123 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2124 { 2125 spin_lock(&sci->sc_state_lock); 2126 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2127 sci->sc_timer.expires = jiffies + sci->sc_interval; 2128 add_timer(&sci->sc_timer); 2129 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2130 } 2131 spin_unlock(&sci->sc_state_lock); 2132 } 2133 2134 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2135 { 2136 spin_lock(&sci->sc_state_lock); 2137 if (!(sci->sc_flush_request & BIT(bn))) { 2138 unsigned long prev_req = sci->sc_flush_request; 2139 2140 sci->sc_flush_request |= BIT(bn); 2141 if (!prev_req) 2142 wake_up(&sci->sc_wait_daemon); 2143 } 2144 spin_unlock(&sci->sc_state_lock); 2145 } 2146 2147 /** 2148 * nilfs_flush_segment - trigger a segment construction for resource control 2149 * @sb: super block 2150 * @ino: inode number of the file to be flushed out. 2151 */ 2152 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2153 { 2154 struct the_nilfs *nilfs = sb->s_fs_info; 2155 struct nilfs_sc_info *sci = nilfs->ns_writer; 2156 2157 if (!sci || nilfs_doing_construction()) 2158 return; 2159 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2160 /* assign bit 0 to data files */ 2161 } 2162 2163 struct nilfs_segctor_wait_request { 2164 wait_queue_t wq; 2165 __u32 seq; 2166 int err; 2167 atomic_t done; 2168 }; 2169 2170 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2171 { 2172 struct nilfs_segctor_wait_request wait_req; 2173 int err = 0; 2174 2175 spin_lock(&sci->sc_state_lock); 2176 init_wait(&wait_req.wq); 2177 wait_req.err = 0; 2178 atomic_set(&wait_req.done, 0); 2179 wait_req.seq = ++sci->sc_seq_request; 2180 spin_unlock(&sci->sc_state_lock); 2181 2182 init_waitqueue_entry(&wait_req.wq, current); 2183 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2184 set_current_state(TASK_INTERRUPTIBLE); 2185 wake_up(&sci->sc_wait_daemon); 2186 2187 for (;;) { 2188 if (atomic_read(&wait_req.done)) { 2189 err = wait_req.err; 2190 break; 2191 } 2192 if (!signal_pending(current)) { 2193 schedule(); 2194 continue; 2195 } 2196 err = -ERESTARTSYS; 2197 break; 2198 } 2199 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2200 return err; 2201 } 2202 2203 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2204 { 2205 struct nilfs_segctor_wait_request *wrq, *n; 2206 unsigned long flags; 2207 2208 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2209 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list, 2210 wq.task_list) { 2211 if (!atomic_read(&wrq->done) && 2212 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { 2213 wrq->err = err; 2214 atomic_set(&wrq->done, 1); 2215 } 2216 if (atomic_read(&wrq->done)) { 2217 wrq->wq.func(&wrq->wq, 2218 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 2219 0, NULL); 2220 } 2221 } 2222 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); 2223 } 2224 2225 /** 2226 * nilfs_construct_segment - construct a logical segment 2227 * @sb: super block 2228 * 2229 * Return Value: On success, 0 is retured. On errors, one of the following 2230 * negative error code is returned. 2231 * 2232 * %-EROFS - Read only filesystem. 2233 * 2234 * %-EIO - I/O error 2235 * 2236 * %-ENOSPC - No space left on device (only in a panic state). 2237 * 2238 * %-ERESTARTSYS - Interrupted. 2239 * 2240 * %-ENOMEM - Insufficient memory available. 2241 */ 2242 int nilfs_construct_segment(struct super_block *sb) 2243 { 2244 struct the_nilfs *nilfs = sb->s_fs_info; 2245 struct nilfs_sc_info *sci = nilfs->ns_writer; 2246 struct nilfs_transaction_info *ti; 2247 int err; 2248 2249 if (!sci) 2250 return -EROFS; 2251 2252 /* A call inside transactions causes a deadlock. */ 2253 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); 2254 2255 err = nilfs_segctor_sync(sci); 2256 return err; 2257 } 2258 2259 /** 2260 * nilfs_construct_dsync_segment - construct a data-only logical segment 2261 * @sb: super block 2262 * @inode: inode whose data blocks should be written out 2263 * @start: start byte offset 2264 * @end: end byte offset (inclusive) 2265 * 2266 * Return Value: On success, 0 is retured. On errors, one of the following 2267 * negative error code is returned. 2268 * 2269 * %-EROFS - Read only filesystem. 2270 * 2271 * %-EIO - I/O error 2272 * 2273 * %-ENOSPC - No space left on device (only in a panic state). 2274 * 2275 * %-ERESTARTSYS - Interrupted. 2276 * 2277 * %-ENOMEM - Insufficient memory available. 2278 */ 2279 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 2280 loff_t start, loff_t end) 2281 { 2282 struct the_nilfs *nilfs = sb->s_fs_info; 2283 struct nilfs_sc_info *sci = nilfs->ns_writer; 2284 struct nilfs_inode_info *ii; 2285 struct nilfs_transaction_info ti; 2286 int err = 0; 2287 2288 if (!sci) 2289 return -EROFS; 2290 2291 nilfs_transaction_lock(sb, &ti, 0); 2292 2293 ii = NILFS_I(inode); 2294 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) || 2295 nilfs_test_opt(nilfs, STRICT_ORDER) || 2296 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2297 nilfs_discontinued(nilfs)) { 2298 nilfs_transaction_unlock(sb); 2299 err = nilfs_segctor_sync(sci); 2300 return err; 2301 } 2302 2303 spin_lock(&nilfs->ns_inode_lock); 2304 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && 2305 !test_bit(NILFS_I_BUSY, &ii->i_state)) { 2306 spin_unlock(&nilfs->ns_inode_lock); 2307 nilfs_transaction_unlock(sb); 2308 return 0; 2309 } 2310 spin_unlock(&nilfs->ns_inode_lock); 2311 sci->sc_dsync_inode = ii; 2312 sci->sc_dsync_start = start; 2313 sci->sc_dsync_end = end; 2314 2315 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); 2316 if (!err) 2317 nilfs->ns_flushed_device = 0; 2318 2319 nilfs_transaction_unlock(sb); 2320 return err; 2321 } 2322 2323 #define FLUSH_FILE_BIT (0x1) /* data file only */ 2324 #define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */ 2325 2326 /** 2327 * nilfs_segctor_accept - record accepted sequence count of log-write requests 2328 * @sci: segment constructor object 2329 */ 2330 static void nilfs_segctor_accept(struct nilfs_sc_info *sci) 2331 { 2332 spin_lock(&sci->sc_state_lock); 2333 sci->sc_seq_accepted = sci->sc_seq_request; 2334 spin_unlock(&sci->sc_state_lock); 2335 del_timer_sync(&sci->sc_timer); 2336 } 2337 2338 /** 2339 * nilfs_segctor_notify - notify the result of request to caller threads 2340 * @sci: segment constructor object 2341 * @mode: mode of log forming 2342 * @err: error code to be notified 2343 */ 2344 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) 2345 { 2346 /* Clear requests (even when the construction failed) */ 2347 spin_lock(&sci->sc_state_lock); 2348 2349 if (mode == SC_LSEG_SR) { 2350 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; 2351 sci->sc_seq_done = sci->sc_seq_accepted; 2352 nilfs_segctor_wakeup(sci, err); 2353 sci->sc_flush_request = 0; 2354 } else { 2355 if (mode == SC_FLUSH_FILE) 2356 sci->sc_flush_request &= ~FLUSH_FILE_BIT; 2357 else if (mode == SC_FLUSH_DAT) 2358 sci->sc_flush_request &= ~FLUSH_DAT_BIT; 2359 2360 /* re-enable timer if checkpoint creation was not done */ 2361 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2362 time_before(jiffies, sci->sc_timer.expires)) 2363 add_timer(&sci->sc_timer); 2364 } 2365 spin_unlock(&sci->sc_state_lock); 2366 } 2367 2368 /** 2369 * nilfs_segctor_construct - form logs and write them to disk 2370 * @sci: segment constructor object 2371 * @mode: mode of log forming 2372 */ 2373 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode) 2374 { 2375 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2376 struct nilfs_super_block **sbp; 2377 int err = 0; 2378 2379 nilfs_segctor_accept(sci); 2380 2381 if (nilfs_discontinued(nilfs)) 2382 mode = SC_LSEG_SR; 2383 if (!nilfs_segctor_confirm(sci)) 2384 err = nilfs_segctor_do_construct(sci, mode); 2385 2386 if (likely(!err)) { 2387 if (mode != SC_FLUSH_DAT) 2388 atomic_set(&nilfs->ns_ndirtyblks, 0); 2389 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && 2390 nilfs_discontinued(nilfs)) { 2391 down_write(&nilfs->ns_sem); 2392 err = -EIO; 2393 sbp = nilfs_prepare_super(sci->sc_super, 2394 nilfs_sb_will_flip(nilfs)); 2395 if (likely(sbp)) { 2396 nilfs_set_log_cursor(sbp[0], nilfs); 2397 err = nilfs_commit_super(sci->sc_super, 2398 NILFS_SB_COMMIT); 2399 } 2400 up_write(&nilfs->ns_sem); 2401 } 2402 } 2403 2404 nilfs_segctor_notify(sci, mode, err); 2405 return err; 2406 } 2407 2408 static void nilfs_construction_timeout(unsigned long data) 2409 { 2410 struct task_struct *p = (struct task_struct *)data; 2411 2412 wake_up_process(p); 2413 } 2414 2415 static void 2416 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) 2417 { 2418 struct nilfs_inode_info *ii, *n; 2419 2420 list_for_each_entry_safe(ii, n, head, i_dirty) { 2421 if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) 2422 continue; 2423 list_del_init(&ii->i_dirty); 2424 truncate_inode_pages(&ii->vfs_inode.i_data, 0); 2425 nilfs_btnode_cache_clear(&ii->i_btnode_cache); 2426 iput(&ii->vfs_inode); 2427 } 2428 } 2429 2430 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, 2431 void **kbufs) 2432 { 2433 struct the_nilfs *nilfs = sb->s_fs_info; 2434 struct nilfs_sc_info *sci = nilfs->ns_writer; 2435 struct nilfs_transaction_info ti; 2436 int err; 2437 2438 if (unlikely(!sci)) 2439 return -EROFS; 2440 2441 nilfs_transaction_lock(sb, &ti, 1); 2442 2443 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat); 2444 if (unlikely(err)) 2445 goto out_unlock; 2446 2447 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs); 2448 if (unlikely(err)) { 2449 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat); 2450 goto out_unlock; 2451 } 2452 2453 sci->sc_freesegs = kbufs[4]; 2454 sci->sc_nfreesegs = argv[4].v_nmembs; 2455 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes); 2456 2457 for (;;) { 2458 err = nilfs_segctor_construct(sci, SC_LSEG_SR); 2459 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); 2460 2461 if (likely(!err)) 2462 break; 2463 2464 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err); 2465 set_current_state(TASK_INTERRUPTIBLE); 2466 schedule_timeout(sci->sc_interval); 2467 } 2468 if (nilfs_test_opt(nilfs, DISCARD)) { 2469 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, 2470 sci->sc_nfreesegs); 2471 if (ret) { 2472 nilfs_msg(sb, KERN_WARNING, 2473 "error %d on discard request, turning discards off for the device", 2474 ret); 2475 nilfs_clear_opt(nilfs, DISCARD); 2476 } 2477 } 2478 2479 out_unlock: 2480 sci->sc_freesegs = NULL; 2481 sci->sc_nfreesegs = 0; 2482 nilfs_mdt_clear_shadow_map(nilfs->ns_dat); 2483 nilfs_transaction_unlock(sb); 2484 return err; 2485 } 2486 2487 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2488 { 2489 struct nilfs_transaction_info ti; 2490 2491 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2492 nilfs_segctor_construct(sci, mode); 2493 2494 /* 2495 * Unclosed segment should be retried. We do this using sc_timer. 2496 * Timeout of sc_timer will invoke complete construction which leads 2497 * to close the current logical segment. 2498 */ 2499 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2500 nilfs_segctor_start_timer(sci); 2501 2502 nilfs_transaction_unlock(sci->sc_super); 2503 } 2504 2505 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2506 { 2507 int mode = 0; 2508 2509 spin_lock(&sci->sc_state_lock); 2510 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2511 SC_FLUSH_DAT : SC_FLUSH_FILE; 2512 spin_unlock(&sci->sc_state_lock); 2513 2514 if (mode) { 2515 nilfs_segctor_do_construct(sci, mode); 2516 2517 spin_lock(&sci->sc_state_lock); 2518 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2519 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2520 spin_unlock(&sci->sc_state_lock); 2521 } 2522 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2523 } 2524 2525 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2526 { 2527 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2528 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2529 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2530 return SC_FLUSH_FILE; 2531 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2532 return SC_FLUSH_DAT; 2533 } 2534 return SC_LSEG_SR; 2535 } 2536 2537 /** 2538 * nilfs_segctor_thread - main loop of the segment constructor thread. 2539 * @arg: pointer to a struct nilfs_sc_info. 2540 * 2541 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2542 * to execute segment constructions. 2543 */ 2544 static int nilfs_segctor_thread(void *arg) 2545 { 2546 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2547 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2548 int timeout = 0; 2549 2550 sci->sc_timer.data = (unsigned long)current; 2551 sci->sc_timer.function = nilfs_construction_timeout; 2552 2553 /* start sync. */ 2554 sci->sc_task = current; 2555 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2556 nilfs_msg(sci->sc_super, KERN_INFO, 2557 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds", 2558 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2559 2560 spin_lock(&sci->sc_state_lock); 2561 loop: 2562 for (;;) { 2563 int mode; 2564 2565 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2566 goto end_thread; 2567 2568 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2569 mode = SC_LSEG_SR; 2570 else if (sci->sc_flush_request) 2571 mode = nilfs_segctor_flush_mode(sci); 2572 else 2573 break; 2574 2575 spin_unlock(&sci->sc_state_lock); 2576 nilfs_segctor_thread_construct(sci, mode); 2577 spin_lock(&sci->sc_state_lock); 2578 timeout = 0; 2579 } 2580 2581 2582 if (freezing(current)) { 2583 spin_unlock(&sci->sc_state_lock); 2584 try_to_freeze(); 2585 spin_lock(&sci->sc_state_lock); 2586 } else { 2587 DEFINE_WAIT(wait); 2588 int should_sleep = 1; 2589 2590 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2591 TASK_INTERRUPTIBLE); 2592 2593 if (sci->sc_seq_request != sci->sc_seq_done) 2594 should_sleep = 0; 2595 else if (sci->sc_flush_request) 2596 should_sleep = 0; 2597 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2598 should_sleep = time_before(jiffies, 2599 sci->sc_timer.expires); 2600 2601 if (should_sleep) { 2602 spin_unlock(&sci->sc_state_lock); 2603 schedule(); 2604 spin_lock(&sci->sc_state_lock); 2605 } 2606 finish_wait(&sci->sc_wait_daemon, &wait); 2607 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2608 time_after_eq(jiffies, sci->sc_timer.expires)); 2609 2610 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) 2611 set_nilfs_discontinued(nilfs); 2612 } 2613 goto loop; 2614 2615 end_thread: 2616 spin_unlock(&sci->sc_state_lock); 2617 2618 /* end sync. */ 2619 sci->sc_task = NULL; 2620 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2621 return 0; 2622 } 2623 2624 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2625 { 2626 struct task_struct *t; 2627 2628 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2629 if (IS_ERR(t)) { 2630 int err = PTR_ERR(t); 2631 2632 nilfs_msg(sci->sc_super, KERN_ERR, 2633 "error %d creating segctord thread", err); 2634 return err; 2635 } 2636 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2637 return 0; 2638 } 2639 2640 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2641 __acquires(&sci->sc_state_lock) 2642 __releases(&sci->sc_state_lock) 2643 { 2644 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2645 2646 while (sci->sc_task) { 2647 wake_up(&sci->sc_wait_daemon); 2648 spin_unlock(&sci->sc_state_lock); 2649 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2650 spin_lock(&sci->sc_state_lock); 2651 } 2652 } 2653 2654 /* 2655 * Setup & clean-up functions 2656 */ 2657 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb, 2658 struct nilfs_root *root) 2659 { 2660 struct the_nilfs *nilfs = sb->s_fs_info; 2661 struct nilfs_sc_info *sci; 2662 2663 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2664 if (!sci) 2665 return NULL; 2666 2667 sci->sc_super = sb; 2668 2669 nilfs_get_root(root); 2670 sci->sc_root = root; 2671 2672 init_waitqueue_head(&sci->sc_wait_request); 2673 init_waitqueue_head(&sci->sc_wait_daemon); 2674 init_waitqueue_head(&sci->sc_wait_task); 2675 spin_lock_init(&sci->sc_state_lock); 2676 INIT_LIST_HEAD(&sci->sc_dirty_files); 2677 INIT_LIST_HEAD(&sci->sc_segbufs); 2678 INIT_LIST_HEAD(&sci->sc_write_logs); 2679 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2680 INIT_LIST_HEAD(&sci->sc_iput_queue); 2681 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func); 2682 init_timer(&sci->sc_timer); 2683 2684 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2685 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2686 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2687 2688 if (nilfs->ns_interval) 2689 sci->sc_interval = HZ * nilfs->ns_interval; 2690 if (nilfs->ns_watermark) 2691 sci->sc_watermark = nilfs->ns_watermark; 2692 return sci; 2693 } 2694 2695 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2696 { 2697 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2698 2699 /* 2700 * The segctord thread was stopped and its timer was removed. 2701 * But some tasks remain. 2702 */ 2703 do { 2704 struct nilfs_transaction_info ti; 2705 2706 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2707 ret = nilfs_segctor_construct(sci, SC_LSEG_SR); 2708 nilfs_transaction_unlock(sci->sc_super); 2709 2710 flush_work(&sci->sc_iput_work); 2711 2712 } while (ret && retrycount-- > 0); 2713 } 2714 2715 /** 2716 * nilfs_segctor_destroy - destroy the segment constructor. 2717 * @sci: nilfs_sc_info 2718 * 2719 * nilfs_segctor_destroy() kills the segctord thread and frees 2720 * the nilfs_sc_info struct. 2721 * Caller must hold the segment semaphore. 2722 */ 2723 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2724 { 2725 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2726 int flag; 2727 2728 up_write(&nilfs->ns_segctor_sem); 2729 2730 spin_lock(&sci->sc_state_lock); 2731 nilfs_segctor_kill_thread(sci); 2732 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2733 || sci->sc_seq_request != sci->sc_seq_done); 2734 spin_unlock(&sci->sc_state_lock); 2735 2736 if (flush_work(&sci->sc_iput_work)) 2737 flag = true; 2738 2739 if (flag || !nilfs_segctor_confirm(sci)) 2740 nilfs_segctor_write_out(sci); 2741 2742 if (!list_empty(&sci->sc_dirty_files)) { 2743 nilfs_msg(sci->sc_super, KERN_WARNING, 2744 "disposed unprocessed dirty file(s) when stopping log writer"); 2745 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1); 2746 } 2747 2748 if (!list_empty(&sci->sc_iput_queue)) { 2749 nilfs_msg(sci->sc_super, KERN_WARNING, 2750 "disposed unprocessed inode(s) in iput queue when stopping log writer"); 2751 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1); 2752 } 2753 2754 WARN_ON(!list_empty(&sci->sc_segbufs)); 2755 WARN_ON(!list_empty(&sci->sc_write_logs)); 2756 2757 nilfs_put_root(sci->sc_root); 2758 2759 down_write(&nilfs->ns_segctor_sem); 2760 2761 del_timer_sync(&sci->sc_timer); 2762 kfree(sci); 2763 } 2764 2765 /** 2766 * nilfs_attach_log_writer - attach log writer 2767 * @sb: super block instance 2768 * @root: root object of the current filesystem tree 2769 * 2770 * This allocates a log writer object, initializes it, and starts the 2771 * log writer. 2772 * 2773 * Return Value: On success, 0 is returned. On error, one of the following 2774 * negative error code is returned. 2775 * 2776 * %-ENOMEM - Insufficient memory available. 2777 */ 2778 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root) 2779 { 2780 struct the_nilfs *nilfs = sb->s_fs_info; 2781 int err; 2782 2783 if (nilfs->ns_writer) { 2784 /* 2785 * This happens if the filesystem was remounted 2786 * read/write after nilfs_error degenerated it into a 2787 * read-only mount. 2788 */ 2789 nilfs_detach_log_writer(sb); 2790 } 2791 2792 nilfs->ns_writer = nilfs_segctor_new(sb, root); 2793 if (!nilfs->ns_writer) 2794 return -ENOMEM; 2795 2796 err = nilfs_segctor_start_thread(nilfs->ns_writer); 2797 if (err) { 2798 kfree(nilfs->ns_writer); 2799 nilfs->ns_writer = NULL; 2800 } 2801 return err; 2802 } 2803 2804 /** 2805 * nilfs_detach_log_writer - destroy log writer 2806 * @sb: super block instance 2807 * 2808 * This kills log writer daemon, frees the log writer object, and 2809 * destroys list of dirty files. 2810 */ 2811 void nilfs_detach_log_writer(struct super_block *sb) 2812 { 2813 struct the_nilfs *nilfs = sb->s_fs_info; 2814 LIST_HEAD(garbage_list); 2815 2816 down_write(&nilfs->ns_segctor_sem); 2817 if (nilfs->ns_writer) { 2818 nilfs_segctor_destroy(nilfs->ns_writer); 2819 nilfs->ns_writer = NULL; 2820 } 2821 2822 /* Force to free the list of dirty files */ 2823 spin_lock(&nilfs->ns_inode_lock); 2824 if (!list_empty(&nilfs->ns_dirty_files)) { 2825 list_splice_init(&nilfs->ns_dirty_files, &garbage_list); 2826 nilfs_msg(sb, KERN_WARNING, 2827 "disposed unprocessed dirty file(s) when detaching log writer"); 2828 } 2829 spin_unlock(&nilfs->ns_inode_lock); 2830 up_write(&nilfs->ns_segctor_sem); 2831 2832 nilfs_dispose_list(nilfs, &garbage_list, 1); 2833 } 2834