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); 712 repeat: 713 if (unlikely(index > last) || 714 !pagevec_lookup_range_tag(&pvec, mapping, &index, last, 715 PAGECACHE_TAG_DIRTY)) 716 return ndirties; 717 718 for (i = 0; i < pagevec_count(&pvec); i++) { 719 struct buffer_head *bh, *head; 720 struct page *page = pvec.pages[i]; 721 722 lock_page(page); 723 if (!page_has_buffers(page)) 724 create_empty_buffers(page, i_blocksize(inode), 0); 725 unlock_page(page); 726 727 bh = head = page_buffers(page); 728 do { 729 if (!buffer_dirty(bh) || buffer_async_write(bh)) 730 continue; 731 get_bh(bh); 732 list_add_tail(&bh->b_assoc_buffers, listp); 733 ndirties++; 734 if (unlikely(ndirties >= nlimit)) { 735 pagevec_release(&pvec); 736 cond_resched(); 737 return ndirties; 738 } 739 } while (bh = bh->b_this_page, bh != head); 740 } 741 pagevec_release(&pvec); 742 cond_resched(); 743 goto repeat; 744 } 745 746 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 747 struct list_head *listp) 748 { 749 struct nilfs_inode_info *ii = NILFS_I(inode); 750 struct address_space *mapping = &ii->i_btnode_cache; 751 struct pagevec pvec; 752 struct buffer_head *bh, *head; 753 unsigned int i; 754 pgoff_t index = 0; 755 756 pagevec_init(&pvec); 757 758 while (pagevec_lookup_tag(&pvec, mapping, &index, 759 PAGECACHE_TAG_DIRTY)) { 760 for (i = 0; i < pagevec_count(&pvec); i++) { 761 bh = head = page_buffers(pvec.pages[i]); 762 do { 763 if (buffer_dirty(bh) && 764 !buffer_async_write(bh)) { 765 get_bh(bh); 766 list_add_tail(&bh->b_assoc_buffers, 767 listp); 768 } 769 bh = bh->b_this_page; 770 } while (bh != head); 771 } 772 pagevec_release(&pvec); 773 cond_resched(); 774 } 775 } 776 777 static void nilfs_dispose_list(struct the_nilfs *nilfs, 778 struct list_head *head, int force) 779 { 780 struct nilfs_inode_info *ii, *n; 781 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 782 unsigned int nv = 0; 783 784 while (!list_empty(head)) { 785 spin_lock(&nilfs->ns_inode_lock); 786 list_for_each_entry_safe(ii, n, head, i_dirty) { 787 list_del_init(&ii->i_dirty); 788 if (force) { 789 if (unlikely(ii->i_bh)) { 790 brelse(ii->i_bh); 791 ii->i_bh = NULL; 792 } 793 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 794 set_bit(NILFS_I_QUEUED, &ii->i_state); 795 list_add_tail(&ii->i_dirty, 796 &nilfs->ns_dirty_files); 797 continue; 798 } 799 ivec[nv++] = ii; 800 if (nv == SC_N_INODEVEC) 801 break; 802 } 803 spin_unlock(&nilfs->ns_inode_lock); 804 805 for (pii = ivec; nv > 0; pii++, nv--) 806 iput(&(*pii)->vfs_inode); 807 } 808 } 809 810 static void nilfs_iput_work_func(struct work_struct *work) 811 { 812 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info, 813 sc_iput_work); 814 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 815 816 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0); 817 } 818 819 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs, 820 struct nilfs_root *root) 821 { 822 int ret = 0; 823 824 if (nilfs_mdt_fetch_dirty(root->ifile)) 825 ret++; 826 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 827 ret++; 828 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 829 ret++; 830 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat)) 831 ret++; 832 return ret; 833 } 834 835 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 836 { 837 return list_empty(&sci->sc_dirty_files) && 838 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 839 sci->sc_nfreesegs == 0 && 840 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 841 } 842 843 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 844 { 845 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 846 int ret = 0; 847 848 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 849 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 850 851 spin_lock(&nilfs->ns_inode_lock); 852 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci)) 853 ret++; 854 855 spin_unlock(&nilfs->ns_inode_lock); 856 return ret; 857 } 858 859 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 860 { 861 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 862 863 nilfs_mdt_clear_dirty(sci->sc_root->ifile); 864 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 865 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 866 nilfs_mdt_clear_dirty(nilfs->ns_dat); 867 } 868 869 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 870 { 871 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 872 struct buffer_head *bh_cp; 873 struct nilfs_checkpoint *raw_cp; 874 int err; 875 876 /* XXX: this interface will be changed */ 877 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 878 &raw_cp, &bh_cp); 879 if (likely(!err)) { 880 /* 881 * The following code is duplicated with cpfile. But, it is 882 * needed to collect the checkpoint even if it was not newly 883 * created. 884 */ 885 mark_buffer_dirty(bh_cp); 886 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 887 nilfs_cpfile_put_checkpoint( 888 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 889 } else 890 WARN_ON(err == -EINVAL || err == -ENOENT); 891 892 return err; 893 } 894 895 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 896 { 897 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 898 struct buffer_head *bh_cp; 899 struct nilfs_checkpoint *raw_cp; 900 int err; 901 902 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 903 &raw_cp, &bh_cp); 904 if (unlikely(err)) { 905 WARN_ON(err == -EINVAL || err == -ENOENT); 906 goto failed_ibh; 907 } 908 raw_cp->cp_snapshot_list.ssl_next = 0; 909 raw_cp->cp_snapshot_list.ssl_prev = 0; 910 raw_cp->cp_inodes_count = 911 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count)); 912 raw_cp->cp_blocks_count = 913 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count)); 914 raw_cp->cp_nblk_inc = 915 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 916 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 917 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 918 919 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 920 nilfs_checkpoint_clear_minor(raw_cp); 921 else 922 nilfs_checkpoint_set_minor(raw_cp); 923 924 nilfs_write_inode_common(sci->sc_root->ifile, 925 &raw_cp->cp_ifile_inode, 1); 926 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 927 return 0; 928 929 failed_ibh: 930 return err; 931 } 932 933 static void nilfs_fill_in_file_bmap(struct inode *ifile, 934 struct nilfs_inode_info *ii) 935 936 { 937 struct buffer_head *ibh; 938 struct nilfs_inode *raw_inode; 939 940 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 941 ibh = ii->i_bh; 942 BUG_ON(!ibh); 943 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 944 ibh); 945 nilfs_bmap_write(ii->i_bmap, raw_inode); 946 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 947 } 948 } 949 950 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci) 951 { 952 struct nilfs_inode_info *ii; 953 954 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 955 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii); 956 set_bit(NILFS_I_COLLECTED, &ii->i_state); 957 } 958 } 959 960 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 961 struct the_nilfs *nilfs) 962 { 963 struct buffer_head *bh_sr; 964 struct nilfs_super_root *raw_sr; 965 unsigned int isz, srsz; 966 967 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root; 968 raw_sr = (struct nilfs_super_root *)bh_sr->b_data; 969 isz = nilfs->ns_inode_size; 970 srsz = NILFS_SR_BYTES(isz); 971 972 raw_sr->sr_bytes = cpu_to_le16(srsz); 973 raw_sr->sr_nongc_ctime 974 = cpu_to_le64(nilfs_doing_gc() ? 975 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 976 raw_sr->sr_flags = 0; 977 978 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr + 979 NILFS_SR_DAT_OFFSET(isz), 1); 980 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr + 981 NILFS_SR_CPFILE_OFFSET(isz), 1); 982 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr + 983 NILFS_SR_SUFILE_OFFSET(isz), 1); 984 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz); 985 } 986 987 static void nilfs_redirty_inodes(struct list_head *head) 988 { 989 struct nilfs_inode_info *ii; 990 991 list_for_each_entry(ii, head, i_dirty) { 992 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 993 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 994 } 995 } 996 997 static void nilfs_drop_collected_inodes(struct list_head *head) 998 { 999 struct nilfs_inode_info *ii; 1000 1001 list_for_each_entry(ii, head, i_dirty) { 1002 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 1003 continue; 1004 1005 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state); 1006 set_bit(NILFS_I_UPDATED, &ii->i_state); 1007 } 1008 } 1009 1010 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 1011 struct inode *inode, 1012 struct list_head *listp, 1013 int (*collect)(struct nilfs_sc_info *, 1014 struct buffer_head *, 1015 struct inode *)) 1016 { 1017 struct buffer_head *bh, *n; 1018 int err = 0; 1019 1020 if (collect) { 1021 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 1022 list_del_init(&bh->b_assoc_buffers); 1023 err = collect(sci, bh, inode); 1024 brelse(bh); 1025 if (unlikely(err)) 1026 goto dispose_buffers; 1027 } 1028 return 0; 1029 } 1030 1031 dispose_buffers: 1032 while (!list_empty(listp)) { 1033 bh = list_first_entry(listp, struct buffer_head, 1034 b_assoc_buffers); 1035 list_del_init(&bh->b_assoc_buffers); 1036 brelse(bh); 1037 } 1038 return err; 1039 } 1040 1041 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 1042 { 1043 /* Remaining number of blocks within segment buffer */ 1044 return sci->sc_segbuf_nblocks - 1045 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 1046 } 1047 1048 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 1049 struct inode *inode, 1050 const struct nilfs_sc_operations *sc_ops) 1051 { 1052 LIST_HEAD(data_buffers); 1053 LIST_HEAD(node_buffers); 1054 int err; 1055 1056 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1057 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1058 1059 n = nilfs_lookup_dirty_data_buffers( 1060 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 1061 if (n > rest) { 1062 err = nilfs_segctor_apply_buffers( 1063 sci, inode, &data_buffers, 1064 sc_ops->collect_data); 1065 BUG_ON(!err); /* always receive -E2BIG or true error */ 1066 goto break_or_fail; 1067 } 1068 } 1069 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 1070 1071 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1072 err = nilfs_segctor_apply_buffers( 1073 sci, inode, &data_buffers, sc_ops->collect_data); 1074 if (unlikely(err)) { 1075 /* dispose node list */ 1076 nilfs_segctor_apply_buffers( 1077 sci, inode, &node_buffers, NULL); 1078 goto break_or_fail; 1079 } 1080 sci->sc_stage.flags |= NILFS_CF_NODE; 1081 } 1082 /* Collect node */ 1083 err = nilfs_segctor_apply_buffers( 1084 sci, inode, &node_buffers, sc_ops->collect_node); 1085 if (unlikely(err)) 1086 goto break_or_fail; 1087 1088 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1089 err = nilfs_segctor_apply_buffers( 1090 sci, inode, &node_buffers, sc_ops->collect_bmap); 1091 if (unlikely(err)) 1092 goto break_or_fail; 1093 1094 nilfs_segctor_end_finfo(sci, inode); 1095 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1096 1097 break_or_fail: 1098 return err; 1099 } 1100 1101 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1102 struct inode *inode) 1103 { 1104 LIST_HEAD(data_buffers); 1105 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1106 int err; 1107 1108 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1109 sci->sc_dsync_start, 1110 sci->sc_dsync_end); 1111 1112 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1113 nilfs_collect_file_data); 1114 if (!err) { 1115 nilfs_segctor_end_finfo(sci, inode); 1116 BUG_ON(n > rest); 1117 /* always receive -E2BIG or true error if n > rest */ 1118 } 1119 return err; 1120 } 1121 1122 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1123 { 1124 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1125 struct list_head *head; 1126 struct nilfs_inode_info *ii; 1127 size_t ndone; 1128 int err = 0; 1129 1130 switch (nilfs_sc_cstage_get(sci)) { 1131 case NILFS_ST_INIT: 1132 /* Pre-processes */ 1133 sci->sc_stage.flags = 0; 1134 1135 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1136 sci->sc_nblk_inc = 0; 1137 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1138 if (mode == SC_LSEG_DSYNC) { 1139 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC); 1140 goto dsync_mode; 1141 } 1142 } 1143 1144 sci->sc_stage.dirty_file_ptr = NULL; 1145 sci->sc_stage.gc_inode_ptr = NULL; 1146 if (mode == SC_FLUSH_DAT) { 1147 nilfs_sc_cstage_set(sci, NILFS_ST_DAT); 1148 goto dat_stage; 1149 } 1150 nilfs_sc_cstage_inc(sci); /* Fall through */ 1151 case NILFS_ST_GC: 1152 if (nilfs_doing_gc()) { 1153 head = &sci->sc_gc_inodes; 1154 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1155 head, i_dirty); 1156 list_for_each_entry_continue(ii, head, i_dirty) { 1157 err = nilfs_segctor_scan_file( 1158 sci, &ii->vfs_inode, 1159 &nilfs_sc_file_ops); 1160 if (unlikely(err)) { 1161 sci->sc_stage.gc_inode_ptr = list_entry( 1162 ii->i_dirty.prev, 1163 struct nilfs_inode_info, 1164 i_dirty); 1165 goto break_or_fail; 1166 } 1167 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1168 } 1169 sci->sc_stage.gc_inode_ptr = NULL; 1170 } 1171 nilfs_sc_cstage_inc(sci); /* Fall through */ 1172 case NILFS_ST_FILE: 1173 head = &sci->sc_dirty_files; 1174 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1175 i_dirty); 1176 list_for_each_entry_continue(ii, head, i_dirty) { 1177 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1178 1179 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1180 &nilfs_sc_file_ops); 1181 if (unlikely(err)) { 1182 sci->sc_stage.dirty_file_ptr = 1183 list_entry(ii->i_dirty.prev, 1184 struct nilfs_inode_info, 1185 i_dirty); 1186 goto break_or_fail; 1187 } 1188 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1189 /* XXX: required ? */ 1190 } 1191 sci->sc_stage.dirty_file_ptr = NULL; 1192 if (mode == SC_FLUSH_FILE) { 1193 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1194 return 0; 1195 } 1196 nilfs_sc_cstage_inc(sci); 1197 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1198 /* Fall through */ 1199 case NILFS_ST_IFILE: 1200 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile, 1201 &nilfs_sc_file_ops); 1202 if (unlikely(err)) 1203 break; 1204 nilfs_sc_cstage_inc(sci); 1205 /* Creating a checkpoint */ 1206 err = nilfs_segctor_create_checkpoint(sci); 1207 if (unlikely(err)) 1208 break; 1209 /* Fall through */ 1210 case NILFS_ST_CPFILE: 1211 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1212 &nilfs_sc_file_ops); 1213 if (unlikely(err)) 1214 break; 1215 nilfs_sc_cstage_inc(sci); /* Fall through */ 1216 case NILFS_ST_SUFILE: 1217 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1218 sci->sc_nfreesegs, &ndone); 1219 if (unlikely(err)) { 1220 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1221 sci->sc_freesegs, ndone, 1222 NULL); 1223 break; 1224 } 1225 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1226 1227 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1228 &nilfs_sc_file_ops); 1229 if (unlikely(err)) 1230 break; 1231 nilfs_sc_cstage_inc(sci); /* Fall through */ 1232 case NILFS_ST_DAT: 1233 dat_stage: 1234 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat, 1235 &nilfs_sc_dat_ops); 1236 if (unlikely(err)) 1237 break; 1238 if (mode == SC_FLUSH_DAT) { 1239 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1240 return 0; 1241 } 1242 nilfs_sc_cstage_inc(sci); /* Fall through */ 1243 case NILFS_ST_SR: 1244 if (mode == SC_LSEG_SR) { 1245 /* Appending a super root */ 1246 err = nilfs_segctor_add_super_root(sci); 1247 if (unlikely(err)) 1248 break; 1249 } 1250 /* End of a logical segment */ 1251 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1252 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1253 return 0; 1254 case NILFS_ST_DSYNC: 1255 dsync_mode: 1256 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1257 ii = sci->sc_dsync_inode; 1258 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1259 break; 1260 1261 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1262 if (unlikely(err)) 1263 break; 1264 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1265 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1266 return 0; 1267 case NILFS_ST_DONE: 1268 return 0; 1269 default: 1270 BUG(); 1271 } 1272 1273 break_or_fail: 1274 return err; 1275 } 1276 1277 /** 1278 * nilfs_segctor_begin_construction - setup segment buffer to make a new log 1279 * @sci: nilfs_sc_info 1280 * @nilfs: nilfs object 1281 */ 1282 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1283 struct the_nilfs *nilfs) 1284 { 1285 struct nilfs_segment_buffer *segbuf, *prev; 1286 __u64 nextnum; 1287 int err, alloc = 0; 1288 1289 segbuf = nilfs_segbuf_new(sci->sc_super); 1290 if (unlikely(!segbuf)) 1291 return -ENOMEM; 1292 1293 if (list_empty(&sci->sc_write_logs)) { 1294 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 1295 nilfs->ns_pseg_offset, nilfs); 1296 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1297 nilfs_shift_to_next_segment(nilfs); 1298 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1299 } 1300 1301 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1302 nextnum = nilfs->ns_nextnum; 1303 1304 if (nilfs->ns_segnum == nilfs->ns_nextnum) 1305 /* Start from the head of a new full segment */ 1306 alloc++; 1307 } else { 1308 /* Continue logs */ 1309 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1310 nilfs_segbuf_map_cont(segbuf, prev); 1311 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq; 1312 nextnum = prev->sb_nextnum; 1313 1314 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1315 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1316 segbuf->sb_sum.seg_seq++; 1317 alloc++; 1318 } 1319 } 1320 1321 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum); 1322 if (err) 1323 goto failed; 1324 1325 if (alloc) { 1326 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1327 if (err) 1328 goto failed; 1329 } 1330 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1331 1332 BUG_ON(!list_empty(&sci->sc_segbufs)); 1333 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs); 1334 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1335 return 0; 1336 1337 failed: 1338 nilfs_segbuf_free(segbuf); 1339 return err; 1340 } 1341 1342 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1343 struct the_nilfs *nilfs, int nadd) 1344 { 1345 struct nilfs_segment_buffer *segbuf, *prev; 1346 struct inode *sufile = nilfs->ns_sufile; 1347 __u64 nextnextnum; 1348 LIST_HEAD(list); 1349 int err, ret, i; 1350 1351 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1352 /* 1353 * Since the segment specified with nextnum might be allocated during 1354 * the previous construction, the buffer including its segusage may 1355 * not be dirty. The following call ensures that the buffer is dirty 1356 * and will pin the buffer on memory until the sufile is written. 1357 */ 1358 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum); 1359 if (unlikely(err)) 1360 return err; 1361 1362 for (i = 0; i < nadd; i++) { 1363 /* extend segment info */ 1364 err = -ENOMEM; 1365 segbuf = nilfs_segbuf_new(sci->sc_super); 1366 if (unlikely(!segbuf)) 1367 goto failed; 1368 1369 /* map this buffer to region of segment on-disk */ 1370 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1371 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1372 1373 /* allocate the next next full segment */ 1374 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1375 if (unlikely(err)) 1376 goto failed_segbuf; 1377 1378 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1379 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1380 1381 list_add_tail(&segbuf->sb_list, &list); 1382 prev = segbuf; 1383 } 1384 list_splice_tail(&list, &sci->sc_segbufs); 1385 return 0; 1386 1387 failed_segbuf: 1388 nilfs_segbuf_free(segbuf); 1389 failed: 1390 list_for_each_entry(segbuf, &list, sb_list) { 1391 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1392 WARN_ON(ret); /* never fails */ 1393 } 1394 nilfs_destroy_logs(&list); 1395 return err; 1396 } 1397 1398 static void nilfs_free_incomplete_logs(struct list_head *logs, 1399 struct the_nilfs *nilfs) 1400 { 1401 struct nilfs_segment_buffer *segbuf, *prev; 1402 struct inode *sufile = nilfs->ns_sufile; 1403 int ret; 1404 1405 segbuf = NILFS_FIRST_SEGBUF(logs); 1406 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1407 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1408 WARN_ON(ret); /* never fails */ 1409 } 1410 if (atomic_read(&segbuf->sb_err)) { 1411 /* Case 1: The first segment failed */ 1412 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1413 /* 1414 * Case 1a: Partial segment appended into an existing 1415 * segment 1416 */ 1417 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1418 segbuf->sb_fseg_end); 1419 else /* Case 1b: New full segment */ 1420 set_nilfs_discontinued(nilfs); 1421 } 1422 1423 prev = segbuf; 1424 list_for_each_entry_continue(segbuf, logs, sb_list) { 1425 if (prev->sb_nextnum != segbuf->sb_nextnum) { 1426 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1427 WARN_ON(ret); /* never fails */ 1428 } 1429 if (atomic_read(&segbuf->sb_err) && 1430 segbuf->sb_segnum != nilfs->ns_nextnum) 1431 /* Case 2: extended segment (!= next) failed */ 1432 nilfs_sufile_set_error(sufile, segbuf->sb_segnum); 1433 prev = segbuf; 1434 } 1435 } 1436 1437 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1438 struct inode *sufile) 1439 { 1440 struct nilfs_segment_buffer *segbuf; 1441 unsigned long live_blocks; 1442 int ret; 1443 1444 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1445 live_blocks = segbuf->sb_sum.nblocks + 1446 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1447 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1448 live_blocks, 1449 sci->sc_seg_ctime); 1450 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1451 } 1452 } 1453 1454 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile) 1455 { 1456 struct nilfs_segment_buffer *segbuf; 1457 int ret; 1458 1459 segbuf = NILFS_FIRST_SEGBUF(logs); 1460 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1461 segbuf->sb_pseg_start - 1462 segbuf->sb_fseg_start, 0); 1463 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1464 1465 list_for_each_entry_continue(segbuf, logs, sb_list) { 1466 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1467 0, 0); 1468 WARN_ON(ret); /* always succeed */ 1469 } 1470 } 1471 1472 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1473 struct nilfs_segment_buffer *last, 1474 struct inode *sufile) 1475 { 1476 struct nilfs_segment_buffer *segbuf = last; 1477 int ret; 1478 1479 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1480 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1481 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1482 WARN_ON(ret); 1483 } 1484 nilfs_truncate_logs(&sci->sc_segbufs, last); 1485 } 1486 1487 1488 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1489 struct the_nilfs *nilfs, int mode) 1490 { 1491 struct nilfs_cstage prev_stage = sci->sc_stage; 1492 int err, nadd = 1; 1493 1494 /* Collection retry loop */ 1495 for (;;) { 1496 sci->sc_nblk_this_inc = 0; 1497 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1498 1499 err = nilfs_segctor_reset_segment_buffer(sci); 1500 if (unlikely(err)) 1501 goto failed; 1502 1503 err = nilfs_segctor_collect_blocks(sci, mode); 1504 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1505 if (!err) 1506 break; 1507 1508 if (unlikely(err != -E2BIG)) 1509 goto failed; 1510 1511 /* The current segment is filled up */ 1512 if (mode != SC_LSEG_SR || 1513 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE) 1514 break; 1515 1516 nilfs_clear_logs(&sci->sc_segbufs); 1517 1518 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1519 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1520 sci->sc_freesegs, 1521 sci->sc_nfreesegs, 1522 NULL); 1523 WARN_ON(err); /* do not happen */ 1524 sci->sc_stage.flags &= ~NILFS_CF_SUFREED; 1525 } 1526 1527 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1528 if (unlikely(err)) 1529 return err; 1530 1531 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1532 sci->sc_stage = prev_stage; 1533 } 1534 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1535 return 0; 1536 1537 failed: 1538 return err; 1539 } 1540 1541 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1542 struct buffer_head *new_bh) 1543 { 1544 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1545 1546 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1547 /* The caller must release old_bh */ 1548 } 1549 1550 static int 1551 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1552 struct nilfs_segment_buffer *segbuf, 1553 int mode) 1554 { 1555 struct inode *inode = NULL; 1556 sector_t blocknr; 1557 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1558 unsigned long nblocks = 0, ndatablk = 0; 1559 const struct nilfs_sc_operations *sc_op = NULL; 1560 struct nilfs_segsum_pointer ssp; 1561 struct nilfs_finfo *finfo = NULL; 1562 union nilfs_binfo binfo; 1563 struct buffer_head *bh, *bh_org; 1564 ino_t ino = 0; 1565 int err = 0; 1566 1567 if (!nfinfo) 1568 goto out; 1569 1570 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1571 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1572 ssp.offset = sizeof(struct nilfs_segment_summary); 1573 1574 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1575 if (bh == segbuf->sb_super_root) 1576 break; 1577 if (!finfo) { 1578 finfo = nilfs_segctor_map_segsum_entry( 1579 sci, &ssp, sizeof(*finfo)); 1580 ino = le64_to_cpu(finfo->fi_ino); 1581 nblocks = le32_to_cpu(finfo->fi_nblocks); 1582 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1583 1584 inode = bh->b_page->mapping->host; 1585 1586 if (mode == SC_LSEG_DSYNC) 1587 sc_op = &nilfs_sc_dsync_ops; 1588 else if (ino == NILFS_DAT_INO) 1589 sc_op = &nilfs_sc_dat_ops; 1590 else /* file blocks */ 1591 sc_op = &nilfs_sc_file_ops; 1592 } 1593 bh_org = bh; 1594 get_bh(bh_org); 1595 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1596 &binfo); 1597 if (bh != bh_org) 1598 nilfs_list_replace_buffer(bh_org, bh); 1599 brelse(bh_org); 1600 if (unlikely(err)) 1601 goto failed_bmap; 1602 1603 if (ndatablk > 0) 1604 sc_op->write_data_binfo(sci, &ssp, &binfo); 1605 else 1606 sc_op->write_node_binfo(sci, &ssp, &binfo); 1607 1608 blocknr++; 1609 if (--nblocks == 0) { 1610 finfo = NULL; 1611 if (--nfinfo == 0) 1612 break; 1613 } else if (ndatablk > 0) 1614 ndatablk--; 1615 } 1616 out: 1617 return 0; 1618 1619 failed_bmap: 1620 return err; 1621 } 1622 1623 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1624 { 1625 struct nilfs_segment_buffer *segbuf; 1626 int err; 1627 1628 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1629 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1630 if (unlikely(err)) 1631 return err; 1632 nilfs_segbuf_fill_in_segsum(segbuf); 1633 } 1634 return 0; 1635 } 1636 1637 static void nilfs_begin_page_io(struct page *page) 1638 { 1639 if (!page || PageWriteback(page)) 1640 /* 1641 * For split b-tree node pages, this function may be called 1642 * twice. We ignore the 2nd or later calls by this check. 1643 */ 1644 return; 1645 1646 lock_page(page); 1647 clear_page_dirty_for_io(page); 1648 set_page_writeback(page); 1649 unlock_page(page); 1650 } 1651 1652 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci) 1653 { 1654 struct nilfs_segment_buffer *segbuf; 1655 struct page *bd_page = NULL, *fs_page = NULL; 1656 1657 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1658 struct buffer_head *bh; 1659 1660 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1661 b_assoc_buffers) { 1662 if (bh->b_page != bd_page) { 1663 if (bd_page) { 1664 lock_page(bd_page); 1665 clear_page_dirty_for_io(bd_page); 1666 set_page_writeback(bd_page); 1667 unlock_page(bd_page); 1668 } 1669 bd_page = bh->b_page; 1670 } 1671 } 1672 1673 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1674 b_assoc_buffers) { 1675 set_buffer_async_write(bh); 1676 if (bh == segbuf->sb_super_root) { 1677 if (bh->b_page != bd_page) { 1678 lock_page(bd_page); 1679 clear_page_dirty_for_io(bd_page); 1680 set_page_writeback(bd_page); 1681 unlock_page(bd_page); 1682 bd_page = bh->b_page; 1683 } 1684 break; 1685 } 1686 if (bh->b_page != fs_page) { 1687 nilfs_begin_page_io(fs_page); 1688 fs_page = bh->b_page; 1689 } 1690 } 1691 } 1692 if (bd_page) { 1693 lock_page(bd_page); 1694 clear_page_dirty_for_io(bd_page); 1695 set_page_writeback(bd_page); 1696 unlock_page(bd_page); 1697 } 1698 nilfs_begin_page_io(fs_page); 1699 } 1700 1701 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1702 struct the_nilfs *nilfs) 1703 { 1704 int ret; 1705 1706 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs); 1707 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs); 1708 return ret; 1709 } 1710 1711 static void nilfs_end_page_io(struct page *page, int err) 1712 { 1713 if (!page) 1714 return; 1715 1716 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) { 1717 /* 1718 * For b-tree node pages, this function may be called twice 1719 * or more because they might be split in a segment. 1720 */ 1721 if (PageDirty(page)) { 1722 /* 1723 * For pages holding split b-tree node buffers, dirty 1724 * flag on the buffers may be cleared discretely. 1725 * In that case, the page is once redirtied for 1726 * remaining buffers, and it must be cancelled if 1727 * all the buffers get cleaned later. 1728 */ 1729 lock_page(page); 1730 if (nilfs_page_buffers_clean(page)) 1731 __nilfs_clear_page_dirty(page); 1732 unlock_page(page); 1733 } 1734 return; 1735 } 1736 1737 if (!err) { 1738 if (!nilfs_page_buffers_clean(page)) 1739 __set_page_dirty_nobuffers(page); 1740 ClearPageError(page); 1741 } else { 1742 __set_page_dirty_nobuffers(page); 1743 SetPageError(page); 1744 } 1745 1746 end_page_writeback(page); 1747 } 1748 1749 static void nilfs_abort_logs(struct list_head *logs, int err) 1750 { 1751 struct nilfs_segment_buffer *segbuf; 1752 struct page *bd_page = NULL, *fs_page = NULL; 1753 struct buffer_head *bh; 1754 1755 if (list_empty(logs)) 1756 return; 1757 1758 list_for_each_entry(segbuf, logs, sb_list) { 1759 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1760 b_assoc_buffers) { 1761 if (bh->b_page != bd_page) { 1762 if (bd_page) 1763 end_page_writeback(bd_page); 1764 bd_page = bh->b_page; 1765 } 1766 } 1767 1768 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1769 b_assoc_buffers) { 1770 clear_buffer_async_write(bh); 1771 if (bh == segbuf->sb_super_root) { 1772 if (bh->b_page != bd_page) { 1773 end_page_writeback(bd_page); 1774 bd_page = bh->b_page; 1775 } 1776 break; 1777 } 1778 if (bh->b_page != fs_page) { 1779 nilfs_end_page_io(fs_page, err); 1780 fs_page = bh->b_page; 1781 } 1782 } 1783 } 1784 if (bd_page) 1785 end_page_writeback(bd_page); 1786 1787 nilfs_end_page_io(fs_page, err); 1788 } 1789 1790 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci, 1791 struct the_nilfs *nilfs, int err) 1792 { 1793 LIST_HEAD(logs); 1794 int ret; 1795 1796 list_splice_tail_init(&sci->sc_write_logs, &logs); 1797 ret = nilfs_wait_on_logs(&logs); 1798 nilfs_abort_logs(&logs, ret ? : err); 1799 1800 list_splice_tail_init(&sci->sc_segbufs, &logs); 1801 nilfs_cancel_segusage(&logs, nilfs->ns_sufile); 1802 nilfs_free_incomplete_logs(&logs, nilfs); 1803 1804 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1805 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1806 sci->sc_freesegs, 1807 sci->sc_nfreesegs, 1808 NULL); 1809 WARN_ON(ret); /* do not happen */ 1810 } 1811 1812 nilfs_destroy_logs(&logs); 1813 } 1814 1815 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1816 struct nilfs_segment_buffer *segbuf) 1817 { 1818 nilfs->ns_segnum = segbuf->sb_segnum; 1819 nilfs->ns_nextnum = segbuf->sb_nextnum; 1820 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1821 + segbuf->sb_sum.nblocks; 1822 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1823 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1824 } 1825 1826 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1827 { 1828 struct nilfs_segment_buffer *segbuf; 1829 struct page *bd_page = NULL, *fs_page = NULL; 1830 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1831 int update_sr = false; 1832 1833 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) { 1834 struct buffer_head *bh; 1835 1836 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1837 b_assoc_buffers) { 1838 set_buffer_uptodate(bh); 1839 clear_buffer_dirty(bh); 1840 if (bh->b_page != bd_page) { 1841 if (bd_page) 1842 end_page_writeback(bd_page); 1843 bd_page = bh->b_page; 1844 } 1845 } 1846 /* 1847 * We assume that the buffers which belong to the same page 1848 * continue over the buffer list. 1849 * Under this assumption, the last BHs of pages is 1850 * identifiable by the discontinuity of bh->b_page 1851 * (page != fs_page). 1852 * 1853 * For B-tree node blocks, however, this assumption is not 1854 * guaranteed. The cleanup code of B-tree node pages needs 1855 * special care. 1856 */ 1857 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1858 b_assoc_buffers) { 1859 const unsigned long set_bits = BIT(BH_Uptodate); 1860 const unsigned long clear_bits = 1861 (BIT(BH_Dirty) | BIT(BH_Async_Write) | 1862 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) | 1863 BIT(BH_NILFS_Redirected)); 1864 1865 set_mask_bits(&bh->b_state, clear_bits, set_bits); 1866 if (bh == segbuf->sb_super_root) { 1867 if (bh->b_page != bd_page) { 1868 end_page_writeback(bd_page); 1869 bd_page = bh->b_page; 1870 } 1871 update_sr = true; 1872 break; 1873 } 1874 if (bh->b_page != fs_page) { 1875 nilfs_end_page_io(fs_page, 0); 1876 fs_page = bh->b_page; 1877 } 1878 } 1879 1880 if (!nilfs_segbuf_simplex(segbuf)) { 1881 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) { 1882 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1883 sci->sc_lseg_stime = jiffies; 1884 } 1885 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND) 1886 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1887 } 1888 } 1889 /* 1890 * Since pages may continue over multiple segment buffers, 1891 * end of the last page must be checked outside of the loop. 1892 */ 1893 if (bd_page) 1894 end_page_writeback(bd_page); 1895 1896 nilfs_end_page_io(fs_page, 0); 1897 1898 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 1899 1900 if (nilfs_doing_gc()) 1901 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 1902 else 1903 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 1904 1905 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 1906 1907 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1908 nilfs_set_next_segment(nilfs, segbuf); 1909 1910 if (update_sr) { 1911 nilfs->ns_flushed_device = 0; 1912 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 1913 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 1914 1915 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 1916 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 1917 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1918 nilfs_segctor_clear_metadata_dirty(sci); 1919 } else 1920 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1921 } 1922 1923 static int nilfs_segctor_wait(struct nilfs_sc_info *sci) 1924 { 1925 int ret; 1926 1927 ret = nilfs_wait_on_logs(&sci->sc_write_logs); 1928 if (!ret) { 1929 nilfs_segctor_complete_write(sci); 1930 nilfs_destroy_logs(&sci->sc_write_logs); 1931 } 1932 return ret; 1933 } 1934 1935 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci, 1936 struct the_nilfs *nilfs) 1937 { 1938 struct nilfs_inode_info *ii, *n; 1939 struct inode *ifile = sci->sc_root->ifile; 1940 1941 spin_lock(&nilfs->ns_inode_lock); 1942 retry: 1943 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) { 1944 if (!ii->i_bh) { 1945 struct buffer_head *ibh; 1946 int err; 1947 1948 spin_unlock(&nilfs->ns_inode_lock); 1949 err = nilfs_ifile_get_inode_block( 1950 ifile, ii->vfs_inode.i_ino, &ibh); 1951 if (unlikely(err)) { 1952 nilfs_msg(sci->sc_super, KERN_WARNING, 1953 "log writer: error %d getting inode block (ino=%lu)", 1954 err, ii->vfs_inode.i_ino); 1955 return err; 1956 } 1957 spin_lock(&nilfs->ns_inode_lock); 1958 if (likely(!ii->i_bh)) 1959 ii->i_bh = ibh; 1960 else 1961 brelse(ibh); 1962 goto retry; 1963 } 1964 1965 // Always redirty the buffer to avoid race condition 1966 mark_buffer_dirty(ii->i_bh); 1967 nilfs_mdt_mark_dirty(ifile); 1968 1969 clear_bit(NILFS_I_QUEUED, &ii->i_state); 1970 set_bit(NILFS_I_BUSY, &ii->i_state); 1971 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files); 1972 } 1973 spin_unlock(&nilfs->ns_inode_lock); 1974 1975 return 0; 1976 } 1977 1978 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci, 1979 struct the_nilfs *nilfs) 1980 { 1981 struct nilfs_inode_info *ii, *n; 1982 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE); 1983 int defer_iput = false; 1984 1985 spin_lock(&nilfs->ns_inode_lock); 1986 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 1987 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 1988 test_bit(NILFS_I_DIRTY, &ii->i_state)) 1989 continue; 1990 1991 clear_bit(NILFS_I_BUSY, &ii->i_state); 1992 brelse(ii->i_bh); 1993 ii->i_bh = NULL; 1994 list_del_init(&ii->i_dirty); 1995 if (!ii->vfs_inode.i_nlink || during_mount) { 1996 /* 1997 * Defer calling iput() to avoid deadlocks if 1998 * i_nlink == 0 or mount is not yet finished. 1999 */ 2000 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue); 2001 defer_iput = true; 2002 } else { 2003 spin_unlock(&nilfs->ns_inode_lock); 2004 iput(&ii->vfs_inode); 2005 spin_lock(&nilfs->ns_inode_lock); 2006 } 2007 } 2008 spin_unlock(&nilfs->ns_inode_lock); 2009 2010 if (defer_iput) 2011 schedule_work(&sci->sc_iput_work); 2012 } 2013 2014 /* 2015 * Main procedure of segment constructor 2016 */ 2017 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 2018 { 2019 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2020 int err; 2021 2022 nilfs_sc_cstage_set(sci, NILFS_ST_INIT); 2023 sci->sc_cno = nilfs->ns_cno; 2024 2025 err = nilfs_segctor_collect_dirty_files(sci, nilfs); 2026 if (unlikely(err)) 2027 goto out; 2028 2029 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 2030 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2031 2032 if (nilfs_segctor_clean(sci)) 2033 goto out; 2034 2035 do { 2036 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 2037 2038 err = nilfs_segctor_begin_construction(sci, nilfs); 2039 if (unlikely(err)) 2040 goto out; 2041 2042 /* Update time stamp */ 2043 sci->sc_seg_ctime = get_seconds(); 2044 2045 err = nilfs_segctor_collect(sci, nilfs, mode); 2046 if (unlikely(err)) 2047 goto failed; 2048 2049 /* Avoid empty segment */ 2050 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE && 2051 nilfs_segbuf_empty(sci->sc_curseg)) { 2052 nilfs_segctor_abort_construction(sci, nilfs, 1); 2053 goto out; 2054 } 2055 2056 err = nilfs_segctor_assign(sci, mode); 2057 if (unlikely(err)) 2058 goto failed; 2059 2060 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2061 nilfs_segctor_fill_in_file_bmap(sci); 2062 2063 if (mode == SC_LSEG_SR && 2064 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) { 2065 err = nilfs_segctor_fill_in_checkpoint(sci); 2066 if (unlikely(err)) 2067 goto failed_to_write; 2068 2069 nilfs_segctor_fill_in_super_root(sci, nilfs); 2070 } 2071 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 2072 2073 /* Write partial segments */ 2074 nilfs_segctor_prepare_write(sci); 2075 2076 nilfs_add_checksums_on_logs(&sci->sc_segbufs, 2077 nilfs->ns_crc_seed); 2078 2079 err = nilfs_segctor_write(sci, nilfs); 2080 if (unlikely(err)) 2081 goto failed_to_write; 2082 2083 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE || 2084 nilfs->ns_blocksize_bits != PAGE_SHIFT) { 2085 /* 2086 * At this point, we avoid double buffering 2087 * for blocksize < pagesize because page dirty 2088 * flag is turned off during write and dirty 2089 * buffers are not properly collected for 2090 * pages crossing over segments. 2091 */ 2092 err = nilfs_segctor_wait(sci); 2093 if (err) 2094 goto failed_to_write; 2095 } 2096 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE); 2097 2098 out: 2099 nilfs_segctor_drop_written_files(sci, nilfs); 2100 return err; 2101 2102 failed_to_write: 2103 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2104 nilfs_redirty_inodes(&sci->sc_dirty_files); 2105 2106 failed: 2107 if (nilfs_doing_gc()) 2108 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2109 nilfs_segctor_abort_construction(sci, nilfs, err); 2110 goto out; 2111 } 2112 2113 /** 2114 * nilfs_segctor_start_timer - set timer of background write 2115 * @sci: nilfs_sc_info 2116 * 2117 * If the timer has already been set, it ignores the new request. 2118 * This function MUST be called within a section locking the segment 2119 * semaphore. 2120 */ 2121 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2122 { 2123 spin_lock(&sci->sc_state_lock); 2124 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2125 sci->sc_timer.expires = jiffies + sci->sc_interval; 2126 add_timer(&sci->sc_timer); 2127 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2128 } 2129 spin_unlock(&sci->sc_state_lock); 2130 } 2131 2132 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2133 { 2134 spin_lock(&sci->sc_state_lock); 2135 if (!(sci->sc_flush_request & BIT(bn))) { 2136 unsigned long prev_req = sci->sc_flush_request; 2137 2138 sci->sc_flush_request |= BIT(bn); 2139 if (!prev_req) 2140 wake_up(&sci->sc_wait_daemon); 2141 } 2142 spin_unlock(&sci->sc_state_lock); 2143 } 2144 2145 /** 2146 * nilfs_flush_segment - trigger a segment construction for resource control 2147 * @sb: super block 2148 * @ino: inode number of the file to be flushed out. 2149 */ 2150 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2151 { 2152 struct the_nilfs *nilfs = sb->s_fs_info; 2153 struct nilfs_sc_info *sci = nilfs->ns_writer; 2154 2155 if (!sci || nilfs_doing_construction()) 2156 return; 2157 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2158 /* assign bit 0 to data files */ 2159 } 2160 2161 struct nilfs_segctor_wait_request { 2162 wait_queue_entry_t wq; 2163 __u32 seq; 2164 int err; 2165 atomic_t done; 2166 }; 2167 2168 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2169 { 2170 struct nilfs_segctor_wait_request wait_req; 2171 int err = 0; 2172 2173 spin_lock(&sci->sc_state_lock); 2174 init_wait(&wait_req.wq); 2175 wait_req.err = 0; 2176 atomic_set(&wait_req.done, 0); 2177 wait_req.seq = ++sci->sc_seq_request; 2178 spin_unlock(&sci->sc_state_lock); 2179 2180 init_waitqueue_entry(&wait_req.wq, current); 2181 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2182 set_current_state(TASK_INTERRUPTIBLE); 2183 wake_up(&sci->sc_wait_daemon); 2184 2185 for (;;) { 2186 if (atomic_read(&wait_req.done)) { 2187 err = wait_req.err; 2188 break; 2189 } 2190 if (!signal_pending(current)) { 2191 schedule(); 2192 continue; 2193 } 2194 err = -ERESTARTSYS; 2195 break; 2196 } 2197 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2198 return err; 2199 } 2200 2201 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2202 { 2203 struct nilfs_segctor_wait_request *wrq, *n; 2204 unsigned long flags; 2205 2206 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2207 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) { 2208 if (!atomic_read(&wrq->done) && 2209 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { 2210 wrq->err = err; 2211 atomic_set(&wrq->done, 1); 2212 } 2213 if (atomic_read(&wrq->done)) { 2214 wrq->wq.func(&wrq->wq, 2215 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 2216 0, NULL); 2217 } 2218 } 2219 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); 2220 } 2221 2222 /** 2223 * nilfs_construct_segment - construct a logical segment 2224 * @sb: super block 2225 * 2226 * Return Value: On success, 0 is retured. On errors, one of the following 2227 * negative error code is returned. 2228 * 2229 * %-EROFS - Read only filesystem. 2230 * 2231 * %-EIO - I/O error 2232 * 2233 * %-ENOSPC - No space left on device (only in a panic state). 2234 * 2235 * %-ERESTARTSYS - Interrupted. 2236 * 2237 * %-ENOMEM - Insufficient memory available. 2238 */ 2239 int nilfs_construct_segment(struct super_block *sb) 2240 { 2241 struct the_nilfs *nilfs = sb->s_fs_info; 2242 struct nilfs_sc_info *sci = nilfs->ns_writer; 2243 struct nilfs_transaction_info *ti; 2244 int err; 2245 2246 if (!sci) 2247 return -EROFS; 2248 2249 /* A call inside transactions causes a deadlock. */ 2250 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); 2251 2252 err = nilfs_segctor_sync(sci); 2253 return err; 2254 } 2255 2256 /** 2257 * nilfs_construct_dsync_segment - construct a data-only logical segment 2258 * @sb: super block 2259 * @inode: inode whose data blocks should be written out 2260 * @start: start byte offset 2261 * @end: end byte offset (inclusive) 2262 * 2263 * Return Value: On success, 0 is retured. On errors, one of the following 2264 * negative error code is returned. 2265 * 2266 * %-EROFS - Read only filesystem. 2267 * 2268 * %-EIO - I/O error 2269 * 2270 * %-ENOSPC - No space left on device (only in a panic state). 2271 * 2272 * %-ERESTARTSYS - Interrupted. 2273 * 2274 * %-ENOMEM - Insufficient memory available. 2275 */ 2276 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 2277 loff_t start, loff_t end) 2278 { 2279 struct the_nilfs *nilfs = sb->s_fs_info; 2280 struct nilfs_sc_info *sci = nilfs->ns_writer; 2281 struct nilfs_inode_info *ii; 2282 struct nilfs_transaction_info ti; 2283 int err = 0; 2284 2285 if (!sci) 2286 return -EROFS; 2287 2288 nilfs_transaction_lock(sb, &ti, 0); 2289 2290 ii = NILFS_I(inode); 2291 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) || 2292 nilfs_test_opt(nilfs, STRICT_ORDER) || 2293 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2294 nilfs_discontinued(nilfs)) { 2295 nilfs_transaction_unlock(sb); 2296 err = nilfs_segctor_sync(sci); 2297 return err; 2298 } 2299 2300 spin_lock(&nilfs->ns_inode_lock); 2301 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && 2302 !test_bit(NILFS_I_BUSY, &ii->i_state)) { 2303 spin_unlock(&nilfs->ns_inode_lock); 2304 nilfs_transaction_unlock(sb); 2305 return 0; 2306 } 2307 spin_unlock(&nilfs->ns_inode_lock); 2308 sci->sc_dsync_inode = ii; 2309 sci->sc_dsync_start = start; 2310 sci->sc_dsync_end = end; 2311 2312 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); 2313 if (!err) 2314 nilfs->ns_flushed_device = 0; 2315 2316 nilfs_transaction_unlock(sb); 2317 return err; 2318 } 2319 2320 #define FLUSH_FILE_BIT (0x1) /* data file only */ 2321 #define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */ 2322 2323 /** 2324 * nilfs_segctor_accept - record accepted sequence count of log-write requests 2325 * @sci: segment constructor object 2326 */ 2327 static void nilfs_segctor_accept(struct nilfs_sc_info *sci) 2328 { 2329 spin_lock(&sci->sc_state_lock); 2330 sci->sc_seq_accepted = sci->sc_seq_request; 2331 spin_unlock(&sci->sc_state_lock); 2332 del_timer_sync(&sci->sc_timer); 2333 } 2334 2335 /** 2336 * nilfs_segctor_notify - notify the result of request to caller threads 2337 * @sci: segment constructor object 2338 * @mode: mode of log forming 2339 * @err: error code to be notified 2340 */ 2341 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) 2342 { 2343 /* Clear requests (even when the construction failed) */ 2344 spin_lock(&sci->sc_state_lock); 2345 2346 if (mode == SC_LSEG_SR) { 2347 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; 2348 sci->sc_seq_done = sci->sc_seq_accepted; 2349 nilfs_segctor_wakeup(sci, err); 2350 sci->sc_flush_request = 0; 2351 } else { 2352 if (mode == SC_FLUSH_FILE) 2353 sci->sc_flush_request &= ~FLUSH_FILE_BIT; 2354 else if (mode == SC_FLUSH_DAT) 2355 sci->sc_flush_request &= ~FLUSH_DAT_BIT; 2356 2357 /* re-enable timer if checkpoint creation was not done */ 2358 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2359 time_before(jiffies, sci->sc_timer.expires)) 2360 add_timer(&sci->sc_timer); 2361 } 2362 spin_unlock(&sci->sc_state_lock); 2363 } 2364 2365 /** 2366 * nilfs_segctor_construct - form logs and write them to disk 2367 * @sci: segment constructor object 2368 * @mode: mode of log forming 2369 */ 2370 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode) 2371 { 2372 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2373 struct nilfs_super_block **sbp; 2374 int err = 0; 2375 2376 nilfs_segctor_accept(sci); 2377 2378 if (nilfs_discontinued(nilfs)) 2379 mode = SC_LSEG_SR; 2380 if (!nilfs_segctor_confirm(sci)) 2381 err = nilfs_segctor_do_construct(sci, mode); 2382 2383 if (likely(!err)) { 2384 if (mode != SC_FLUSH_DAT) 2385 atomic_set(&nilfs->ns_ndirtyblks, 0); 2386 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && 2387 nilfs_discontinued(nilfs)) { 2388 down_write(&nilfs->ns_sem); 2389 err = -EIO; 2390 sbp = nilfs_prepare_super(sci->sc_super, 2391 nilfs_sb_will_flip(nilfs)); 2392 if (likely(sbp)) { 2393 nilfs_set_log_cursor(sbp[0], nilfs); 2394 err = nilfs_commit_super(sci->sc_super, 2395 NILFS_SB_COMMIT); 2396 } 2397 up_write(&nilfs->ns_sem); 2398 } 2399 } 2400 2401 nilfs_segctor_notify(sci, mode, err); 2402 return err; 2403 } 2404 2405 static void nilfs_construction_timeout(struct timer_list *t) 2406 { 2407 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer); 2408 2409 wake_up_process(sci->sc_timer_task); 2410 } 2411 2412 static void 2413 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) 2414 { 2415 struct nilfs_inode_info *ii, *n; 2416 2417 list_for_each_entry_safe(ii, n, head, i_dirty) { 2418 if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) 2419 continue; 2420 list_del_init(&ii->i_dirty); 2421 truncate_inode_pages(&ii->vfs_inode.i_data, 0); 2422 nilfs_btnode_cache_clear(&ii->i_btnode_cache); 2423 iput(&ii->vfs_inode); 2424 } 2425 } 2426 2427 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, 2428 void **kbufs) 2429 { 2430 struct the_nilfs *nilfs = sb->s_fs_info; 2431 struct nilfs_sc_info *sci = nilfs->ns_writer; 2432 struct nilfs_transaction_info ti; 2433 int err; 2434 2435 if (unlikely(!sci)) 2436 return -EROFS; 2437 2438 nilfs_transaction_lock(sb, &ti, 1); 2439 2440 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat); 2441 if (unlikely(err)) 2442 goto out_unlock; 2443 2444 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs); 2445 if (unlikely(err)) { 2446 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat); 2447 goto out_unlock; 2448 } 2449 2450 sci->sc_freesegs = kbufs[4]; 2451 sci->sc_nfreesegs = argv[4].v_nmembs; 2452 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes); 2453 2454 for (;;) { 2455 err = nilfs_segctor_construct(sci, SC_LSEG_SR); 2456 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); 2457 2458 if (likely(!err)) 2459 break; 2460 2461 nilfs_msg(sb, KERN_WARNING, "error %d cleaning segments", err); 2462 set_current_state(TASK_INTERRUPTIBLE); 2463 schedule_timeout(sci->sc_interval); 2464 } 2465 if (nilfs_test_opt(nilfs, DISCARD)) { 2466 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, 2467 sci->sc_nfreesegs); 2468 if (ret) { 2469 nilfs_msg(sb, KERN_WARNING, 2470 "error %d on discard request, turning discards off for the device", 2471 ret); 2472 nilfs_clear_opt(nilfs, DISCARD); 2473 } 2474 } 2475 2476 out_unlock: 2477 sci->sc_freesegs = NULL; 2478 sci->sc_nfreesegs = 0; 2479 nilfs_mdt_clear_shadow_map(nilfs->ns_dat); 2480 nilfs_transaction_unlock(sb); 2481 return err; 2482 } 2483 2484 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2485 { 2486 struct nilfs_transaction_info ti; 2487 2488 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2489 nilfs_segctor_construct(sci, mode); 2490 2491 /* 2492 * Unclosed segment should be retried. We do this using sc_timer. 2493 * Timeout of sc_timer will invoke complete construction which leads 2494 * to close the current logical segment. 2495 */ 2496 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2497 nilfs_segctor_start_timer(sci); 2498 2499 nilfs_transaction_unlock(sci->sc_super); 2500 } 2501 2502 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2503 { 2504 int mode = 0; 2505 2506 spin_lock(&sci->sc_state_lock); 2507 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2508 SC_FLUSH_DAT : SC_FLUSH_FILE; 2509 spin_unlock(&sci->sc_state_lock); 2510 2511 if (mode) { 2512 nilfs_segctor_do_construct(sci, mode); 2513 2514 spin_lock(&sci->sc_state_lock); 2515 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2516 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2517 spin_unlock(&sci->sc_state_lock); 2518 } 2519 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2520 } 2521 2522 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2523 { 2524 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2525 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2526 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2527 return SC_FLUSH_FILE; 2528 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2529 return SC_FLUSH_DAT; 2530 } 2531 return SC_LSEG_SR; 2532 } 2533 2534 /** 2535 * nilfs_segctor_thread - main loop of the segment constructor thread. 2536 * @arg: pointer to a struct nilfs_sc_info. 2537 * 2538 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2539 * to execute segment constructions. 2540 */ 2541 static int nilfs_segctor_thread(void *arg) 2542 { 2543 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2544 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2545 int timeout = 0; 2546 2547 sci->sc_timer_task = current; 2548 2549 /* start sync. */ 2550 sci->sc_task = current; 2551 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2552 nilfs_msg(sci->sc_super, KERN_INFO, 2553 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds", 2554 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2555 2556 spin_lock(&sci->sc_state_lock); 2557 loop: 2558 for (;;) { 2559 int mode; 2560 2561 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2562 goto end_thread; 2563 2564 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2565 mode = SC_LSEG_SR; 2566 else if (sci->sc_flush_request) 2567 mode = nilfs_segctor_flush_mode(sci); 2568 else 2569 break; 2570 2571 spin_unlock(&sci->sc_state_lock); 2572 nilfs_segctor_thread_construct(sci, mode); 2573 spin_lock(&sci->sc_state_lock); 2574 timeout = 0; 2575 } 2576 2577 2578 if (freezing(current)) { 2579 spin_unlock(&sci->sc_state_lock); 2580 try_to_freeze(); 2581 spin_lock(&sci->sc_state_lock); 2582 } else { 2583 DEFINE_WAIT(wait); 2584 int should_sleep = 1; 2585 2586 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2587 TASK_INTERRUPTIBLE); 2588 2589 if (sci->sc_seq_request != sci->sc_seq_done) 2590 should_sleep = 0; 2591 else if (sci->sc_flush_request) 2592 should_sleep = 0; 2593 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2594 should_sleep = time_before(jiffies, 2595 sci->sc_timer.expires); 2596 2597 if (should_sleep) { 2598 spin_unlock(&sci->sc_state_lock); 2599 schedule(); 2600 spin_lock(&sci->sc_state_lock); 2601 } 2602 finish_wait(&sci->sc_wait_daemon, &wait); 2603 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2604 time_after_eq(jiffies, sci->sc_timer.expires)); 2605 2606 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) 2607 set_nilfs_discontinued(nilfs); 2608 } 2609 goto loop; 2610 2611 end_thread: 2612 spin_unlock(&sci->sc_state_lock); 2613 2614 /* end sync. */ 2615 sci->sc_task = NULL; 2616 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2617 return 0; 2618 } 2619 2620 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2621 { 2622 struct task_struct *t; 2623 2624 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2625 if (IS_ERR(t)) { 2626 int err = PTR_ERR(t); 2627 2628 nilfs_msg(sci->sc_super, KERN_ERR, 2629 "error %d creating segctord thread", err); 2630 return err; 2631 } 2632 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2633 return 0; 2634 } 2635 2636 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2637 __acquires(&sci->sc_state_lock) 2638 __releases(&sci->sc_state_lock) 2639 { 2640 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2641 2642 while (sci->sc_task) { 2643 wake_up(&sci->sc_wait_daemon); 2644 spin_unlock(&sci->sc_state_lock); 2645 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2646 spin_lock(&sci->sc_state_lock); 2647 } 2648 } 2649 2650 /* 2651 * Setup & clean-up functions 2652 */ 2653 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb, 2654 struct nilfs_root *root) 2655 { 2656 struct the_nilfs *nilfs = sb->s_fs_info; 2657 struct nilfs_sc_info *sci; 2658 2659 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2660 if (!sci) 2661 return NULL; 2662 2663 sci->sc_super = sb; 2664 2665 nilfs_get_root(root); 2666 sci->sc_root = root; 2667 2668 init_waitqueue_head(&sci->sc_wait_request); 2669 init_waitqueue_head(&sci->sc_wait_daemon); 2670 init_waitqueue_head(&sci->sc_wait_task); 2671 spin_lock_init(&sci->sc_state_lock); 2672 INIT_LIST_HEAD(&sci->sc_dirty_files); 2673 INIT_LIST_HEAD(&sci->sc_segbufs); 2674 INIT_LIST_HEAD(&sci->sc_write_logs); 2675 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2676 INIT_LIST_HEAD(&sci->sc_iput_queue); 2677 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func); 2678 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0); 2679 2680 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2681 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2682 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2683 2684 if (nilfs->ns_interval) 2685 sci->sc_interval = HZ * nilfs->ns_interval; 2686 if (nilfs->ns_watermark) 2687 sci->sc_watermark = nilfs->ns_watermark; 2688 return sci; 2689 } 2690 2691 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2692 { 2693 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2694 2695 /* 2696 * The segctord thread was stopped and its timer was removed. 2697 * But some tasks remain. 2698 */ 2699 do { 2700 struct nilfs_transaction_info ti; 2701 2702 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2703 ret = nilfs_segctor_construct(sci, SC_LSEG_SR); 2704 nilfs_transaction_unlock(sci->sc_super); 2705 2706 flush_work(&sci->sc_iput_work); 2707 2708 } while (ret && retrycount-- > 0); 2709 } 2710 2711 /** 2712 * nilfs_segctor_destroy - destroy the segment constructor. 2713 * @sci: nilfs_sc_info 2714 * 2715 * nilfs_segctor_destroy() kills the segctord thread and frees 2716 * the nilfs_sc_info struct. 2717 * Caller must hold the segment semaphore. 2718 */ 2719 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2720 { 2721 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2722 int flag; 2723 2724 up_write(&nilfs->ns_segctor_sem); 2725 2726 spin_lock(&sci->sc_state_lock); 2727 nilfs_segctor_kill_thread(sci); 2728 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2729 || sci->sc_seq_request != sci->sc_seq_done); 2730 spin_unlock(&sci->sc_state_lock); 2731 2732 if (flush_work(&sci->sc_iput_work)) 2733 flag = true; 2734 2735 if (flag || !nilfs_segctor_confirm(sci)) 2736 nilfs_segctor_write_out(sci); 2737 2738 if (!list_empty(&sci->sc_dirty_files)) { 2739 nilfs_msg(sci->sc_super, KERN_WARNING, 2740 "disposed unprocessed dirty file(s) when stopping log writer"); 2741 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1); 2742 } 2743 2744 if (!list_empty(&sci->sc_iput_queue)) { 2745 nilfs_msg(sci->sc_super, KERN_WARNING, 2746 "disposed unprocessed inode(s) in iput queue when stopping log writer"); 2747 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1); 2748 } 2749 2750 WARN_ON(!list_empty(&sci->sc_segbufs)); 2751 WARN_ON(!list_empty(&sci->sc_write_logs)); 2752 2753 nilfs_put_root(sci->sc_root); 2754 2755 down_write(&nilfs->ns_segctor_sem); 2756 2757 del_timer_sync(&sci->sc_timer); 2758 kfree(sci); 2759 } 2760 2761 /** 2762 * nilfs_attach_log_writer - attach log writer 2763 * @sb: super block instance 2764 * @root: root object of the current filesystem tree 2765 * 2766 * This allocates a log writer object, initializes it, and starts the 2767 * log writer. 2768 * 2769 * Return Value: On success, 0 is returned. On error, one of the following 2770 * negative error code is returned. 2771 * 2772 * %-ENOMEM - Insufficient memory available. 2773 */ 2774 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root) 2775 { 2776 struct the_nilfs *nilfs = sb->s_fs_info; 2777 int err; 2778 2779 if (nilfs->ns_writer) { 2780 /* 2781 * This happens if the filesystem was remounted 2782 * read/write after nilfs_error degenerated it into a 2783 * read-only mount. 2784 */ 2785 nilfs_detach_log_writer(sb); 2786 } 2787 2788 nilfs->ns_writer = nilfs_segctor_new(sb, root); 2789 if (!nilfs->ns_writer) 2790 return -ENOMEM; 2791 2792 err = nilfs_segctor_start_thread(nilfs->ns_writer); 2793 if (err) { 2794 kfree(nilfs->ns_writer); 2795 nilfs->ns_writer = NULL; 2796 } 2797 return err; 2798 } 2799 2800 /** 2801 * nilfs_detach_log_writer - destroy log writer 2802 * @sb: super block instance 2803 * 2804 * This kills log writer daemon, frees the log writer object, and 2805 * destroys list of dirty files. 2806 */ 2807 void nilfs_detach_log_writer(struct super_block *sb) 2808 { 2809 struct the_nilfs *nilfs = sb->s_fs_info; 2810 LIST_HEAD(garbage_list); 2811 2812 down_write(&nilfs->ns_segctor_sem); 2813 if (nilfs->ns_writer) { 2814 nilfs_segctor_destroy(nilfs->ns_writer); 2815 nilfs->ns_writer = NULL; 2816 } 2817 2818 /* Force to free the list of dirty files */ 2819 spin_lock(&nilfs->ns_inode_lock); 2820 if (!list_empty(&nilfs->ns_dirty_files)) { 2821 list_splice_init(&nilfs->ns_dirty_files, &garbage_list); 2822 nilfs_msg(sb, KERN_WARNING, 2823 "disposed unprocessed dirty file(s) when detaching log writer"); 2824 } 2825 spin_unlock(&nilfs->ns_inode_lock); 2826 up_write(&nilfs->ns_segctor_sem); 2827 2828 nilfs_dispose_list(nilfs, &garbage_list, 1); 2829 } 2830