1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * segment.c - NILFS segment constructor. 4 * 5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 6 * 7 * Written by Ryusuke Konishi. 8 * 9 */ 10 11 #include <linux/pagemap.h> 12 #include <linux/buffer_head.h> 13 #include <linux/writeback.h> 14 #include <linux/bitops.h> 15 #include <linux/bio.h> 16 #include <linux/completion.h> 17 #include <linux/blkdev.h> 18 #include <linux/backing-dev.h> 19 #include <linux/freezer.h> 20 #include <linux/kthread.h> 21 #include <linux/crc32.h> 22 #include <linux/pagevec.h> 23 #include <linux/slab.h> 24 #include <linux/sched/signal.h> 25 26 #include "nilfs.h" 27 #include "btnode.h" 28 #include "page.h" 29 #include "segment.h" 30 #include "sufile.h" 31 #include "cpfile.h" 32 #include "ifile.h" 33 #include "segbuf.h" 34 35 36 /* 37 * Segment constructor 38 */ 39 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */ 40 41 #define SC_MAX_SEGDELTA 64 /* 42 * Upper limit of the number of segments 43 * appended in collection retry loop 44 */ 45 46 /* Construction mode */ 47 enum { 48 SC_LSEG_SR = 1, /* Make a logical segment having a super root */ 49 SC_LSEG_DSYNC, /* 50 * Flush data blocks of a given file and make 51 * a logical segment without a super root. 52 */ 53 SC_FLUSH_FILE, /* 54 * Flush data files, leads to segment writes without 55 * creating a checkpoint. 56 */ 57 SC_FLUSH_DAT, /* 58 * Flush DAT file. This also creates segments 59 * without a checkpoint. 60 */ 61 }; 62 63 /* Stage numbers of dirty block collection */ 64 enum { 65 NILFS_ST_INIT = 0, 66 NILFS_ST_GC, /* Collecting dirty blocks for GC */ 67 NILFS_ST_FILE, 68 NILFS_ST_IFILE, 69 NILFS_ST_CPFILE, 70 NILFS_ST_SUFILE, 71 NILFS_ST_DAT, 72 NILFS_ST_SR, /* Super root */ 73 NILFS_ST_DSYNC, /* Data sync blocks */ 74 NILFS_ST_DONE, 75 }; 76 77 #define CREATE_TRACE_POINTS 78 #include <trace/events/nilfs2.h> 79 80 /* 81 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are 82 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of 83 * the variable must use them because transition of stage count must involve 84 * trace events (trace_nilfs2_collection_stage_transition). 85 * 86 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't 87 * produce tracepoint events. It is provided just for making the intention 88 * clear. 89 */ 90 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci) 91 { 92 sci->sc_stage.scnt++; 93 trace_nilfs2_collection_stage_transition(sci); 94 } 95 96 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt) 97 { 98 sci->sc_stage.scnt = next_scnt; 99 trace_nilfs2_collection_stage_transition(sci); 100 } 101 102 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci) 103 { 104 return sci->sc_stage.scnt; 105 } 106 107 /* State flags of collection */ 108 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ 109 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ 110 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */ 111 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED) 112 113 /* Operations depending on the construction mode and file type */ 114 struct nilfs_sc_operations { 115 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, 116 struct inode *); 117 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, 118 struct inode *); 119 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, 120 struct inode *); 121 void (*write_data_binfo)(struct nilfs_sc_info *, 122 struct nilfs_segsum_pointer *, 123 union nilfs_binfo *); 124 void (*write_node_binfo)(struct nilfs_sc_info *, 125 struct nilfs_segsum_pointer *, 126 union nilfs_binfo *); 127 }; 128 129 /* 130 * Other definitions 131 */ 132 static void nilfs_segctor_start_timer(struct nilfs_sc_info *); 133 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); 134 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); 135 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int); 136 137 #define nilfs_cnt32_ge(a, b) \ 138 (typecheck(__u32, a) && typecheck(__u32, b) && \ 139 ((__s32)(a) - (__s32)(b) >= 0)) 140 141 static int nilfs_prepare_segment_lock(struct super_block *sb, 142 struct nilfs_transaction_info *ti) 143 { 144 struct nilfs_transaction_info *cur_ti = current->journal_info; 145 void *save = NULL; 146 147 if (cur_ti) { 148 if (cur_ti->ti_magic == NILFS_TI_MAGIC) 149 return ++cur_ti->ti_count; 150 151 /* 152 * If journal_info field is occupied by other FS, 153 * it is saved and will be restored on 154 * nilfs_transaction_commit(). 155 */ 156 nilfs_warn(sb, "journal info from a different FS"); 157 save = current->journal_info; 158 } 159 if (!ti) { 160 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); 161 if (!ti) 162 return -ENOMEM; 163 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; 164 } else { 165 ti->ti_flags = 0; 166 } 167 ti->ti_count = 0; 168 ti->ti_save = save; 169 ti->ti_magic = NILFS_TI_MAGIC; 170 current->journal_info = ti; 171 return 0; 172 } 173 174 /** 175 * nilfs_transaction_begin - start indivisible file operations. 176 * @sb: super block 177 * @ti: nilfs_transaction_info 178 * @vacancy_check: flags for vacancy rate checks 179 * 180 * nilfs_transaction_begin() acquires a reader/writer semaphore, called 181 * the segment semaphore, to make a segment construction and write tasks 182 * exclusive. The function is used with nilfs_transaction_commit() in pairs. 183 * The region enclosed by these two functions can be nested. To avoid a 184 * deadlock, the semaphore is only acquired or released in the outermost call. 185 * 186 * This function allocates a nilfs_transaction_info struct to keep context 187 * information on it. It is initialized and hooked onto the current task in 188 * the outermost call. If a pre-allocated struct is given to @ti, it is used 189 * instead; otherwise a new struct is assigned from a slab. 190 * 191 * When @vacancy_check flag is set, this function will check the amount of 192 * free space, and will wait for the GC to reclaim disk space if low capacity. 193 * 194 * Return Value: On success, 0 is returned. On error, one of the following 195 * negative error code is returned. 196 * 197 * %-ENOMEM - Insufficient memory available. 198 * 199 * %-ENOSPC - No space left on device 200 */ 201 int nilfs_transaction_begin(struct super_block *sb, 202 struct nilfs_transaction_info *ti, 203 int vacancy_check) 204 { 205 struct the_nilfs *nilfs; 206 int ret = nilfs_prepare_segment_lock(sb, ti); 207 struct nilfs_transaction_info *trace_ti; 208 209 if (unlikely(ret < 0)) 210 return ret; 211 if (ret > 0) { 212 trace_ti = current->journal_info; 213 214 trace_nilfs2_transaction_transition(sb, trace_ti, 215 trace_ti->ti_count, trace_ti->ti_flags, 216 TRACE_NILFS2_TRANSACTION_BEGIN); 217 return 0; 218 } 219 220 sb_start_intwrite(sb); 221 222 nilfs = sb->s_fs_info; 223 down_read(&nilfs->ns_segctor_sem); 224 if (vacancy_check && nilfs_near_disk_full(nilfs)) { 225 up_read(&nilfs->ns_segctor_sem); 226 ret = -ENOSPC; 227 goto failed; 228 } 229 230 trace_ti = current->journal_info; 231 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count, 232 trace_ti->ti_flags, 233 TRACE_NILFS2_TRANSACTION_BEGIN); 234 return 0; 235 236 failed: 237 ti = current->journal_info; 238 current->journal_info = ti->ti_save; 239 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 240 kmem_cache_free(nilfs_transaction_cachep, ti); 241 sb_end_intwrite(sb); 242 return ret; 243 } 244 245 /** 246 * nilfs_transaction_commit - commit indivisible file operations. 247 * @sb: super block 248 * 249 * nilfs_transaction_commit() releases the read semaphore which is 250 * acquired by nilfs_transaction_begin(). This is only performed 251 * in outermost call of this function. If a commit flag is set, 252 * nilfs_transaction_commit() sets a timer to start the segment 253 * constructor. If a sync flag is set, it starts construction 254 * directly. 255 */ 256 int nilfs_transaction_commit(struct super_block *sb) 257 { 258 struct nilfs_transaction_info *ti = current->journal_info; 259 struct the_nilfs *nilfs = sb->s_fs_info; 260 int err = 0; 261 262 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 263 ti->ti_flags |= NILFS_TI_COMMIT; 264 if (ti->ti_count > 0) { 265 ti->ti_count--; 266 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 267 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT); 268 return 0; 269 } 270 if (nilfs->ns_writer) { 271 struct nilfs_sc_info *sci = nilfs->ns_writer; 272 273 if (ti->ti_flags & NILFS_TI_COMMIT) 274 nilfs_segctor_start_timer(sci); 275 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark) 276 nilfs_segctor_do_flush(sci, 0); 277 } 278 up_read(&nilfs->ns_segctor_sem); 279 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 280 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT); 281 282 current->journal_info = ti->ti_save; 283 284 if (ti->ti_flags & NILFS_TI_SYNC) 285 err = nilfs_construct_segment(sb); 286 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 287 kmem_cache_free(nilfs_transaction_cachep, ti); 288 sb_end_intwrite(sb); 289 return err; 290 } 291 292 void nilfs_transaction_abort(struct super_block *sb) 293 { 294 struct nilfs_transaction_info *ti = current->journal_info; 295 struct the_nilfs *nilfs = sb->s_fs_info; 296 297 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 298 if (ti->ti_count > 0) { 299 ti->ti_count--; 300 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 301 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT); 302 return; 303 } 304 up_read(&nilfs->ns_segctor_sem); 305 306 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 307 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT); 308 309 current->journal_info = ti->ti_save; 310 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 311 kmem_cache_free(nilfs_transaction_cachep, ti); 312 sb_end_intwrite(sb); 313 } 314 315 void nilfs_relax_pressure_in_lock(struct super_block *sb) 316 { 317 struct the_nilfs *nilfs = sb->s_fs_info; 318 struct nilfs_sc_info *sci = nilfs->ns_writer; 319 320 if (!sci || !sci->sc_flush_request) 321 return; 322 323 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 324 up_read(&nilfs->ns_segctor_sem); 325 326 down_write(&nilfs->ns_segctor_sem); 327 if (sci->sc_flush_request && 328 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { 329 struct nilfs_transaction_info *ti = current->journal_info; 330 331 ti->ti_flags |= NILFS_TI_WRITER; 332 nilfs_segctor_do_immediate_flush(sci); 333 ti->ti_flags &= ~NILFS_TI_WRITER; 334 } 335 downgrade_write(&nilfs->ns_segctor_sem); 336 } 337 338 static void nilfs_transaction_lock(struct super_block *sb, 339 struct nilfs_transaction_info *ti, 340 int gcflag) 341 { 342 struct nilfs_transaction_info *cur_ti = current->journal_info; 343 struct the_nilfs *nilfs = sb->s_fs_info; 344 struct nilfs_sc_info *sci = nilfs->ns_writer; 345 346 WARN_ON(cur_ti); 347 ti->ti_flags = NILFS_TI_WRITER; 348 ti->ti_count = 0; 349 ti->ti_save = cur_ti; 350 ti->ti_magic = NILFS_TI_MAGIC; 351 current->journal_info = ti; 352 353 for (;;) { 354 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 355 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK); 356 357 down_write(&nilfs->ns_segctor_sem); 358 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) 359 break; 360 361 nilfs_segctor_do_immediate_flush(sci); 362 363 up_write(&nilfs->ns_segctor_sem); 364 cond_resched(); 365 } 366 if (gcflag) 367 ti->ti_flags |= NILFS_TI_GC; 368 369 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 370 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK); 371 } 372 373 static void nilfs_transaction_unlock(struct super_block *sb) 374 { 375 struct nilfs_transaction_info *ti = current->journal_info; 376 struct the_nilfs *nilfs = sb->s_fs_info; 377 378 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 379 BUG_ON(ti->ti_count > 0); 380 381 up_write(&nilfs->ns_segctor_sem); 382 current->journal_info = ti->ti_save; 383 384 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 385 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK); 386 } 387 388 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, 389 struct nilfs_segsum_pointer *ssp, 390 unsigned int bytes) 391 { 392 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 393 unsigned int blocksize = sci->sc_super->s_blocksize; 394 void *p; 395 396 if (unlikely(ssp->offset + bytes > blocksize)) { 397 ssp->offset = 0; 398 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, 399 &segbuf->sb_segsum_buffers)); 400 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); 401 } 402 p = ssp->bh->b_data + ssp->offset; 403 ssp->offset += bytes; 404 return p; 405 } 406 407 /** 408 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer 409 * @sci: nilfs_sc_info 410 */ 411 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) 412 { 413 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 414 struct buffer_head *sumbh; 415 unsigned int sumbytes; 416 unsigned int flags = 0; 417 int err; 418 419 if (nilfs_doing_gc()) 420 flags = NILFS_SS_GC; 421 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno); 422 if (unlikely(err)) 423 return err; 424 425 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 426 sumbytes = segbuf->sb_sum.sumbytes; 427 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; 428 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; 429 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 430 return 0; 431 } 432 433 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) 434 { 435 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 436 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) 437 return -E2BIG; /* 438 * The current segment is filled up 439 * (internal code) 440 */ 441 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); 442 return nilfs_segctor_reset_segment_buffer(sci); 443 } 444 445 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) 446 { 447 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 448 int err; 449 450 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { 451 err = nilfs_segctor_feed_segment(sci); 452 if (err) 453 return err; 454 segbuf = sci->sc_curseg; 455 } 456 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root); 457 if (likely(!err)) 458 segbuf->sb_sum.flags |= NILFS_SS_SR; 459 return err; 460 } 461 462 /* 463 * Functions for making segment summary and payloads 464 */ 465 static int nilfs_segctor_segsum_block_required( 466 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, 467 unsigned int binfo_size) 468 { 469 unsigned int blocksize = sci->sc_super->s_blocksize; 470 /* Size of finfo and binfo is enough small against blocksize */ 471 472 return ssp->offset + binfo_size + 473 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > 474 blocksize; 475 } 476 477 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, 478 struct inode *inode) 479 { 480 sci->sc_curseg->sb_sum.nfinfo++; 481 sci->sc_binfo_ptr = sci->sc_finfo_ptr; 482 nilfs_segctor_map_segsum_entry( 483 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); 484 485 if (NILFS_I(inode)->i_root && 486 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 487 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 488 /* skip finfo */ 489 } 490 491 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, 492 struct inode *inode) 493 { 494 struct nilfs_finfo *finfo; 495 struct nilfs_inode_info *ii; 496 struct nilfs_segment_buffer *segbuf; 497 __u64 cno; 498 499 if (sci->sc_blk_cnt == 0) 500 return; 501 502 ii = NILFS_I(inode); 503 504 if (test_bit(NILFS_I_GCINODE, &ii->i_state)) 505 cno = ii->i_cno; 506 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) 507 cno = 0; 508 else 509 cno = sci->sc_cno; 510 511 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, 512 sizeof(*finfo)); 513 finfo->fi_ino = cpu_to_le64(inode->i_ino); 514 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); 515 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); 516 finfo->fi_cno = cpu_to_le64(cno); 517 518 segbuf = sci->sc_curseg; 519 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + 520 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); 521 sci->sc_finfo_ptr = sci->sc_binfo_ptr; 522 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 523 } 524 525 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, 526 struct buffer_head *bh, 527 struct inode *inode, 528 unsigned int binfo_size) 529 { 530 struct nilfs_segment_buffer *segbuf; 531 int required, err = 0; 532 533 retry: 534 segbuf = sci->sc_curseg; 535 required = nilfs_segctor_segsum_block_required( 536 sci, &sci->sc_binfo_ptr, binfo_size); 537 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { 538 nilfs_segctor_end_finfo(sci, inode); 539 err = nilfs_segctor_feed_segment(sci); 540 if (err) 541 return err; 542 goto retry; 543 } 544 if (unlikely(required)) { 545 err = nilfs_segbuf_extend_segsum(segbuf); 546 if (unlikely(err)) 547 goto failed; 548 } 549 if (sci->sc_blk_cnt == 0) 550 nilfs_segctor_begin_finfo(sci, inode); 551 552 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); 553 /* Substitution to vblocknr is delayed until update_blocknr() */ 554 nilfs_segbuf_add_file_buffer(segbuf, bh); 555 sci->sc_blk_cnt++; 556 failed: 557 return err; 558 } 559 560 /* 561 * Callback functions that enumerate, mark, and collect dirty blocks 562 */ 563 static int nilfs_collect_file_data(struct nilfs_sc_info *sci, 564 struct buffer_head *bh, struct inode *inode) 565 { 566 int err; 567 568 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 569 if (err < 0) 570 return err; 571 572 err = nilfs_segctor_add_file_block(sci, bh, inode, 573 sizeof(struct nilfs_binfo_v)); 574 if (!err) 575 sci->sc_datablk_cnt++; 576 return err; 577 } 578 579 static int nilfs_collect_file_node(struct nilfs_sc_info *sci, 580 struct buffer_head *bh, 581 struct inode *inode) 582 { 583 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 584 } 585 586 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, 587 struct buffer_head *bh, 588 struct inode *inode) 589 { 590 WARN_ON(!buffer_dirty(bh)); 591 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 592 } 593 594 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, 595 struct nilfs_segsum_pointer *ssp, 596 union nilfs_binfo *binfo) 597 { 598 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( 599 sci, ssp, sizeof(*binfo_v)); 600 *binfo_v = binfo->bi_v; 601 } 602 603 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, 604 struct nilfs_segsum_pointer *ssp, 605 union nilfs_binfo *binfo) 606 { 607 __le64 *vblocknr = nilfs_segctor_map_segsum_entry( 608 sci, ssp, sizeof(*vblocknr)); 609 *vblocknr = binfo->bi_v.bi_vblocknr; 610 } 611 612 static const struct nilfs_sc_operations nilfs_sc_file_ops = { 613 .collect_data = nilfs_collect_file_data, 614 .collect_node = nilfs_collect_file_node, 615 .collect_bmap = nilfs_collect_file_bmap, 616 .write_data_binfo = nilfs_write_file_data_binfo, 617 .write_node_binfo = nilfs_write_file_node_binfo, 618 }; 619 620 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, 621 struct buffer_head *bh, struct inode *inode) 622 { 623 int err; 624 625 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 626 if (err < 0) 627 return err; 628 629 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 630 if (!err) 631 sci->sc_datablk_cnt++; 632 return err; 633 } 634 635 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, 636 struct buffer_head *bh, struct inode *inode) 637 { 638 WARN_ON(!buffer_dirty(bh)); 639 return nilfs_segctor_add_file_block(sci, bh, inode, 640 sizeof(struct nilfs_binfo_dat)); 641 } 642 643 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, 644 struct nilfs_segsum_pointer *ssp, 645 union nilfs_binfo *binfo) 646 { 647 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, 648 sizeof(*blkoff)); 649 *blkoff = binfo->bi_dat.bi_blkoff; 650 } 651 652 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, 653 struct nilfs_segsum_pointer *ssp, 654 union nilfs_binfo *binfo) 655 { 656 struct nilfs_binfo_dat *binfo_dat = 657 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); 658 *binfo_dat = binfo->bi_dat; 659 } 660 661 static const struct nilfs_sc_operations nilfs_sc_dat_ops = { 662 .collect_data = nilfs_collect_dat_data, 663 .collect_node = nilfs_collect_file_node, 664 .collect_bmap = nilfs_collect_dat_bmap, 665 .write_data_binfo = nilfs_write_dat_data_binfo, 666 .write_node_binfo = nilfs_write_dat_node_binfo, 667 }; 668 669 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = { 670 .collect_data = nilfs_collect_file_data, 671 .collect_node = NULL, 672 .collect_bmap = NULL, 673 .write_data_binfo = nilfs_write_file_data_binfo, 674 .write_node_binfo = NULL, 675 }; 676 677 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, 678 struct list_head *listp, 679 size_t nlimit, 680 loff_t start, loff_t end) 681 { 682 struct address_space *mapping = inode->i_mapping; 683 struct pagevec pvec; 684 pgoff_t index = 0, last = ULONG_MAX; 685 size_t ndirties = 0; 686 int i; 687 688 if (unlikely(start != 0 || end != LLONG_MAX)) { 689 /* 690 * A valid range is given for sync-ing data pages. The 691 * range is rounded to per-page; extra dirty buffers 692 * may be included if blocksize < pagesize. 693 */ 694 index = start >> PAGE_SHIFT; 695 last = end >> PAGE_SHIFT; 696 } 697 pagevec_init(&pvec); 698 repeat: 699 if (unlikely(index > last) || 700 !pagevec_lookup_range_tag(&pvec, mapping, &index, last, 701 PAGECACHE_TAG_DIRTY)) 702 return ndirties; 703 704 for (i = 0; i < pagevec_count(&pvec); i++) { 705 struct buffer_head *bh, *head; 706 struct page *page = pvec.pages[i]; 707 708 lock_page(page); 709 if (!page_has_buffers(page)) 710 create_empty_buffers(page, i_blocksize(inode), 0); 711 unlock_page(page); 712 713 bh = head = page_buffers(page); 714 do { 715 if (!buffer_dirty(bh) || buffer_async_write(bh)) 716 continue; 717 get_bh(bh); 718 list_add_tail(&bh->b_assoc_buffers, listp); 719 ndirties++; 720 if (unlikely(ndirties >= nlimit)) { 721 pagevec_release(&pvec); 722 cond_resched(); 723 return ndirties; 724 } 725 } while (bh = bh->b_this_page, bh != head); 726 } 727 pagevec_release(&pvec); 728 cond_resched(); 729 goto repeat; 730 } 731 732 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 733 struct list_head *listp) 734 { 735 struct nilfs_inode_info *ii = NILFS_I(inode); 736 struct address_space *mapping = &ii->i_btnode_cache; 737 struct pagevec pvec; 738 struct buffer_head *bh, *head; 739 unsigned int i; 740 pgoff_t index = 0; 741 742 pagevec_init(&pvec); 743 744 while (pagevec_lookup_tag(&pvec, mapping, &index, 745 PAGECACHE_TAG_DIRTY)) { 746 for (i = 0; i < pagevec_count(&pvec); i++) { 747 bh = head = page_buffers(pvec.pages[i]); 748 do { 749 if (buffer_dirty(bh) && 750 !buffer_async_write(bh)) { 751 get_bh(bh); 752 list_add_tail(&bh->b_assoc_buffers, 753 listp); 754 } 755 bh = bh->b_this_page; 756 } while (bh != head); 757 } 758 pagevec_release(&pvec); 759 cond_resched(); 760 } 761 } 762 763 static void nilfs_dispose_list(struct the_nilfs *nilfs, 764 struct list_head *head, int force) 765 { 766 struct nilfs_inode_info *ii, *n; 767 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 768 unsigned int nv = 0; 769 770 while (!list_empty(head)) { 771 spin_lock(&nilfs->ns_inode_lock); 772 list_for_each_entry_safe(ii, n, head, i_dirty) { 773 list_del_init(&ii->i_dirty); 774 if (force) { 775 if (unlikely(ii->i_bh)) { 776 brelse(ii->i_bh); 777 ii->i_bh = NULL; 778 } 779 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 780 set_bit(NILFS_I_QUEUED, &ii->i_state); 781 list_add_tail(&ii->i_dirty, 782 &nilfs->ns_dirty_files); 783 continue; 784 } 785 ivec[nv++] = ii; 786 if (nv == SC_N_INODEVEC) 787 break; 788 } 789 spin_unlock(&nilfs->ns_inode_lock); 790 791 for (pii = ivec; nv > 0; pii++, nv--) 792 iput(&(*pii)->vfs_inode); 793 } 794 } 795 796 static void nilfs_iput_work_func(struct work_struct *work) 797 { 798 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info, 799 sc_iput_work); 800 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 801 802 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0); 803 } 804 805 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs, 806 struct nilfs_root *root) 807 { 808 int ret = 0; 809 810 if (nilfs_mdt_fetch_dirty(root->ifile)) 811 ret++; 812 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 813 ret++; 814 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 815 ret++; 816 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat)) 817 ret++; 818 return ret; 819 } 820 821 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 822 { 823 return list_empty(&sci->sc_dirty_files) && 824 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 825 sci->sc_nfreesegs == 0 && 826 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 827 } 828 829 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 830 { 831 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 832 int ret = 0; 833 834 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 835 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 836 837 spin_lock(&nilfs->ns_inode_lock); 838 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci)) 839 ret++; 840 841 spin_unlock(&nilfs->ns_inode_lock); 842 return ret; 843 } 844 845 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 846 { 847 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 848 849 nilfs_mdt_clear_dirty(sci->sc_root->ifile); 850 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 851 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 852 nilfs_mdt_clear_dirty(nilfs->ns_dat); 853 } 854 855 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 856 { 857 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 858 struct buffer_head *bh_cp; 859 struct nilfs_checkpoint *raw_cp; 860 int err; 861 862 /* XXX: this interface will be changed */ 863 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 864 &raw_cp, &bh_cp); 865 if (likely(!err)) { 866 /* 867 * The following code is duplicated with cpfile. But, it is 868 * needed to collect the checkpoint even if it was not newly 869 * created. 870 */ 871 mark_buffer_dirty(bh_cp); 872 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 873 nilfs_cpfile_put_checkpoint( 874 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 875 } else 876 WARN_ON(err == -EINVAL || err == -ENOENT); 877 878 return err; 879 } 880 881 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 882 { 883 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 884 struct buffer_head *bh_cp; 885 struct nilfs_checkpoint *raw_cp; 886 int err; 887 888 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 889 &raw_cp, &bh_cp); 890 if (unlikely(err)) { 891 WARN_ON(err == -EINVAL || err == -ENOENT); 892 goto failed_ibh; 893 } 894 raw_cp->cp_snapshot_list.ssl_next = 0; 895 raw_cp->cp_snapshot_list.ssl_prev = 0; 896 raw_cp->cp_inodes_count = 897 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count)); 898 raw_cp->cp_blocks_count = 899 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count)); 900 raw_cp->cp_nblk_inc = 901 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 902 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 903 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 904 905 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 906 nilfs_checkpoint_clear_minor(raw_cp); 907 else 908 nilfs_checkpoint_set_minor(raw_cp); 909 910 nilfs_write_inode_common(sci->sc_root->ifile, 911 &raw_cp->cp_ifile_inode, 1); 912 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 913 return 0; 914 915 failed_ibh: 916 return err; 917 } 918 919 static void nilfs_fill_in_file_bmap(struct inode *ifile, 920 struct nilfs_inode_info *ii) 921 922 { 923 struct buffer_head *ibh; 924 struct nilfs_inode *raw_inode; 925 926 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 927 ibh = ii->i_bh; 928 BUG_ON(!ibh); 929 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 930 ibh); 931 nilfs_bmap_write(ii->i_bmap, raw_inode); 932 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 933 } 934 } 935 936 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci) 937 { 938 struct nilfs_inode_info *ii; 939 940 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 941 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii); 942 set_bit(NILFS_I_COLLECTED, &ii->i_state); 943 } 944 } 945 946 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 947 struct the_nilfs *nilfs) 948 { 949 struct buffer_head *bh_sr; 950 struct nilfs_super_root *raw_sr; 951 unsigned int isz, srsz; 952 953 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root; 954 raw_sr = (struct nilfs_super_root *)bh_sr->b_data; 955 isz = nilfs->ns_inode_size; 956 srsz = NILFS_SR_BYTES(isz); 957 958 raw_sr->sr_bytes = cpu_to_le16(srsz); 959 raw_sr->sr_nongc_ctime 960 = cpu_to_le64(nilfs_doing_gc() ? 961 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 962 raw_sr->sr_flags = 0; 963 964 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr + 965 NILFS_SR_DAT_OFFSET(isz), 1); 966 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr + 967 NILFS_SR_CPFILE_OFFSET(isz), 1); 968 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr + 969 NILFS_SR_SUFILE_OFFSET(isz), 1); 970 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz); 971 } 972 973 static void nilfs_redirty_inodes(struct list_head *head) 974 { 975 struct nilfs_inode_info *ii; 976 977 list_for_each_entry(ii, head, i_dirty) { 978 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 979 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 980 } 981 } 982 983 static void nilfs_drop_collected_inodes(struct list_head *head) 984 { 985 struct nilfs_inode_info *ii; 986 987 list_for_each_entry(ii, head, i_dirty) { 988 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 989 continue; 990 991 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state); 992 set_bit(NILFS_I_UPDATED, &ii->i_state); 993 } 994 } 995 996 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 997 struct inode *inode, 998 struct list_head *listp, 999 int (*collect)(struct nilfs_sc_info *, 1000 struct buffer_head *, 1001 struct inode *)) 1002 { 1003 struct buffer_head *bh, *n; 1004 int err = 0; 1005 1006 if (collect) { 1007 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 1008 list_del_init(&bh->b_assoc_buffers); 1009 err = collect(sci, bh, inode); 1010 brelse(bh); 1011 if (unlikely(err)) 1012 goto dispose_buffers; 1013 } 1014 return 0; 1015 } 1016 1017 dispose_buffers: 1018 while (!list_empty(listp)) { 1019 bh = list_first_entry(listp, struct buffer_head, 1020 b_assoc_buffers); 1021 list_del_init(&bh->b_assoc_buffers); 1022 brelse(bh); 1023 } 1024 return err; 1025 } 1026 1027 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 1028 { 1029 /* Remaining number of blocks within segment buffer */ 1030 return sci->sc_segbuf_nblocks - 1031 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 1032 } 1033 1034 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 1035 struct inode *inode, 1036 const struct nilfs_sc_operations *sc_ops) 1037 { 1038 LIST_HEAD(data_buffers); 1039 LIST_HEAD(node_buffers); 1040 int err; 1041 1042 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1043 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1044 1045 n = nilfs_lookup_dirty_data_buffers( 1046 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 1047 if (n > rest) { 1048 err = nilfs_segctor_apply_buffers( 1049 sci, inode, &data_buffers, 1050 sc_ops->collect_data); 1051 BUG_ON(!err); /* always receive -E2BIG or true error */ 1052 goto break_or_fail; 1053 } 1054 } 1055 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 1056 1057 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1058 err = nilfs_segctor_apply_buffers( 1059 sci, inode, &data_buffers, sc_ops->collect_data); 1060 if (unlikely(err)) { 1061 /* dispose node list */ 1062 nilfs_segctor_apply_buffers( 1063 sci, inode, &node_buffers, NULL); 1064 goto break_or_fail; 1065 } 1066 sci->sc_stage.flags |= NILFS_CF_NODE; 1067 } 1068 /* Collect node */ 1069 err = nilfs_segctor_apply_buffers( 1070 sci, inode, &node_buffers, sc_ops->collect_node); 1071 if (unlikely(err)) 1072 goto break_or_fail; 1073 1074 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1075 err = nilfs_segctor_apply_buffers( 1076 sci, inode, &node_buffers, sc_ops->collect_bmap); 1077 if (unlikely(err)) 1078 goto break_or_fail; 1079 1080 nilfs_segctor_end_finfo(sci, inode); 1081 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1082 1083 break_or_fail: 1084 return err; 1085 } 1086 1087 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1088 struct inode *inode) 1089 { 1090 LIST_HEAD(data_buffers); 1091 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1092 int err; 1093 1094 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1095 sci->sc_dsync_start, 1096 sci->sc_dsync_end); 1097 1098 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1099 nilfs_collect_file_data); 1100 if (!err) { 1101 nilfs_segctor_end_finfo(sci, inode); 1102 BUG_ON(n > rest); 1103 /* always receive -E2BIG or true error if n > rest */ 1104 } 1105 return err; 1106 } 1107 1108 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1109 { 1110 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1111 struct list_head *head; 1112 struct nilfs_inode_info *ii; 1113 size_t ndone; 1114 int err = 0; 1115 1116 switch (nilfs_sc_cstage_get(sci)) { 1117 case NILFS_ST_INIT: 1118 /* Pre-processes */ 1119 sci->sc_stage.flags = 0; 1120 1121 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1122 sci->sc_nblk_inc = 0; 1123 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1124 if (mode == SC_LSEG_DSYNC) { 1125 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC); 1126 goto dsync_mode; 1127 } 1128 } 1129 1130 sci->sc_stage.dirty_file_ptr = NULL; 1131 sci->sc_stage.gc_inode_ptr = NULL; 1132 if (mode == SC_FLUSH_DAT) { 1133 nilfs_sc_cstage_set(sci, NILFS_ST_DAT); 1134 goto dat_stage; 1135 } 1136 nilfs_sc_cstage_inc(sci); 1137 fallthrough; 1138 case NILFS_ST_GC: 1139 if (nilfs_doing_gc()) { 1140 head = &sci->sc_gc_inodes; 1141 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1142 head, i_dirty); 1143 list_for_each_entry_continue(ii, head, i_dirty) { 1144 err = nilfs_segctor_scan_file( 1145 sci, &ii->vfs_inode, 1146 &nilfs_sc_file_ops); 1147 if (unlikely(err)) { 1148 sci->sc_stage.gc_inode_ptr = list_entry( 1149 ii->i_dirty.prev, 1150 struct nilfs_inode_info, 1151 i_dirty); 1152 goto break_or_fail; 1153 } 1154 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1155 } 1156 sci->sc_stage.gc_inode_ptr = NULL; 1157 } 1158 nilfs_sc_cstage_inc(sci); 1159 fallthrough; 1160 case NILFS_ST_FILE: 1161 head = &sci->sc_dirty_files; 1162 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1163 i_dirty); 1164 list_for_each_entry_continue(ii, head, i_dirty) { 1165 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1166 1167 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1168 &nilfs_sc_file_ops); 1169 if (unlikely(err)) { 1170 sci->sc_stage.dirty_file_ptr = 1171 list_entry(ii->i_dirty.prev, 1172 struct nilfs_inode_info, 1173 i_dirty); 1174 goto break_or_fail; 1175 } 1176 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1177 /* XXX: required ? */ 1178 } 1179 sci->sc_stage.dirty_file_ptr = NULL; 1180 if (mode == SC_FLUSH_FILE) { 1181 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1182 return 0; 1183 } 1184 nilfs_sc_cstage_inc(sci); 1185 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1186 fallthrough; 1187 case NILFS_ST_IFILE: 1188 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile, 1189 &nilfs_sc_file_ops); 1190 if (unlikely(err)) 1191 break; 1192 nilfs_sc_cstage_inc(sci); 1193 /* Creating a checkpoint */ 1194 err = nilfs_segctor_create_checkpoint(sci); 1195 if (unlikely(err)) 1196 break; 1197 fallthrough; 1198 case NILFS_ST_CPFILE: 1199 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1200 &nilfs_sc_file_ops); 1201 if (unlikely(err)) 1202 break; 1203 nilfs_sc_cstage_inc(sci); 1204 fallthrough; 1205 case NILFS_ST_SUFILE: 1206 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1207 sci->sc_nfreesegs, &ndone); 1208 if (unlikely(err)) { 1209 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1210 sci->sc_freesegs, ndone, 1211 NULL); 1212 break; 1213 } 1214 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1215 1216 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1217 &nilfs_sc_file_ops); 1218 if (unlikely(err)) 1219 break; 1220 nilfs_sc_cstage_inc(sci); 1221 fallthrough; 1222 case NILFS_ST_DAT: 1223 dat_stage: 1224 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat, 1225 &nilfs_sc_dat_ops); 1226 if (unlikely(err)) 1227 break; 1228 if (mode == SC_FLUSH_DAT) { 1229 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1230 return 0; 1231 } 1232 nilfs_sc_cstage_inc(sci); 1233 fallthrough; 1234 case NILFS_ST_SR: 1235 if (mode == SC_LSEG_SR) { 1236 /* Appending a super root */ 1237 err = nilfs_segctor_add_super_root(sci); 1238 if (unlikely(err)) 1239 break; 1240 } 1241 /* End of a logical segment */ 1242 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1243 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1244 return 0; 1245 case NILFS_ST_DSYNC: 1246 dsync_mode: 1247 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1248 ii = sci->sc_dsync_inode; 1249 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1250 break; 1251 1252 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1253 if (unlikely(err)) 1254 break; 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_DONE: 1259 return 0; 1260 default: 1261 BUG(); 1262 } 1263 1264 break_or_fail: 1265 return err; 1266 } 1267 1268 /** 1269 * nilfs_segctor_begin_construction - setup segment buffer to make a new log 1270 * @sci: nilfs_sc_info 1271 * @nilfs: nilfs object 1272 */ 1273 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1274 struct the_nilfs *nilfs) 1275 { 1276 struct nilfs_segment_buffer *segbuf, *prev; 1277 __u64 nextnum; 1278 int err, alloc = 0; 1279 1280 segbuf = nilfs_segbuf_new(sci->sc_super); 1281 if (unlikely(!segbuf)) 1282 return -ENOMEM; 1283 1284 if (list_empty(&sci->sc_write_logs)) { 1285 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 1286 nilfs->ns_pseg_offset, nilfs); 1287 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1288 nilfs_shift_to_next_segment(nilfs); 1289 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1290 } 1291 1292 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1293 nextnum = nilfs->ns_nextnum; 1294 1295 if (nilfs->ns_segnum == nilfs->ns_nextnum) 1296 /* Start from the head of a new full segment */ 1297 alloc++; 1298 } else { 1299 /* Continue logs */ 1300 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1301 nilfs_segbuf_map_cont(segbuf, prev); 1302 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq; 1303 nextnum = prev->sb_nextnum; 1304 1305 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1306 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1307 segbuf->sb_sum.seg_seq++; 1308 alloc++; 1309 } 1310 } 1311 1312 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum); 1313 if (err) 1314 goto failed; 1315 1316 if (alloc) { 1317 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1318 if (err) 1319 goto failed; 1320 } 1321 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1322 1323 BUG_ON(!list_empty(&sci->sc_segbufs)); 1324 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs); 1325 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1326 return 0; 1327 1328 failed: 1329 nilfs_segbuf_free(segbuf); 1330 return err; 1331 } 1332 1333 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1334 struct the_nilfs *nilfs, int nadd) 1335 { 1336 struct nilfs_segment_buffer *segbuf, *prev; 1337 struct inode *sufile = nilfs->ns_sufile; 1338 __u64 nextnextnum; 1339 LIST_HEAD(list); 1340 int err, ret, i; 1341 1342 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1343 /* 1344 * Since the segment specified with nextnum might be allocated during 1345 * the previous construction, the buffer including its segusage may 1346 * not be dirty. The following call ensures that the buffer is dirty 1347 * and will pin the buffer on memory until the sufile is written. 1348 */ 1349 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum); 1350 if (unlikely(err)) 1351 return err; 1352 1353 for (i = 0; i < nadd; i++) { 1354 /* extend segment info */ 1355 err = -ENOMEM; 1356 segbuf = nilfs_segbuf_new(sci->sc_super); 1357 if (unlikely(!segbuf)) 1358 goto failed; 1359 1360 /* map this buffer to region of segment on-disk */ 1361 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1362 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1363 1364 /* allocate the next next full segment */ 1365 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1366 if (unlikely(err)) 1367 goto failed_segbuf; 1368 1369 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1370 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1371 1372 list_add_tail(&segbuf->sb_list, &list); 1373 prev = segbuf; 1374 } 1375 list_splice_tail(&list, &sci->sc_segbufs); 1376 return 0; 1377 1378 failed_segbuf: 1379 nilfs_segbuf_free(segbuf); 1380 failed: 1381 list_for_each_entry(segbuf, &list, sb_list) { 1382 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1383 WARN_ON(ret); /* never fails */ 1384 } 1385 nilfs_destroy_logs(&list); 1386 return err; 1387 } 1388 1389 static void nilfs_free_incomplete_logs(struct list_head *logs, 1390 struct the_nilfs *nilfs) 1391 { 1392 struct nilfs_segment_buffer *segbuf, *prev; 1393 struct inode *sufile = nilfs->ns_sufile; 1394 int ret; 1395 1396 segbuf = NILFS_FIRST_SEGBUF(logs); 1397 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1398 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1399 WARN_ON(ret); /* never fails */ 1400 } 1401 if (atomic_read(&segbuf->sb_err)) { 1402 /* Case 1: The first segment failed */ 1403 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1404 /* 1405 * Case 1a: Partial segment appended into an existing 1406 * segment 1407 */ 1408 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1409 segbuf->sb_fseg_end); 1410 else /* Case 1b: New full segment */ 1411 set_nilfs_discontinued(nilfs); 1412 } 1413 1414 prev = segbuf; 1415 list_for_each_entry_continue(segbuf, logs, sb_list) { 1416 if (prev->sb_nextnum != segbuf->sb_nextnum) { 1417 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1418 WARN_ON(ret); /* never fails */ 1419 } 1420 if (atomic_read(&segbuf->sb_err) && 1421 segbuf->sb_segnum != nilfs->ns_nextnum) 1422 /* Case 2: extended segment (!= next) failed */ 1423 nilfs_sufile_set_error(sufile, segbuf->sb_segnum); 1424 prev = segbuf; 1425 } 1426 } 1427 1428 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1429 struct inode *sufile) 1430 { 1431 struct nilfs_segment_buffer *segbuf; 1432 unsigned long live_blocks; 1433 int ret; 1434 1435 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1436 live_blocks = segbuf->sb_sum.nblocks + 1437 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1438 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1439 live_blocks, 1440 sci->sc_seg_ctime); 1441 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1442 } 1443 } 1444 1445 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile) 1446 { 1447 struct nilfs_segment_buffer *segbuf; 1448 int ret; 1449 1450 segbuf = NILFS_FIRST_SEGBUF(logs); 1451 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1452 segbuf->sb_pseg_start - 1453 segbuf->sb_fseg_start, 0); 1454 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1455 1456 list_for_each_entry_continue(segbuf, logs, sb_list) { 1457 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1458 0, 0); 1459 WARN_ON(ret); /* always succeed */ 1460 } 1461 } 1462 1463 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1464 struct nilfs_segment_buffer *last, 1465 struct inode *sufile) 1466 { 1467 struct nilfs_segment_buffer *segbuf = last; 1468 int ret; 1469 1470 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1471 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1472 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1473 WARN_ON(ret); 1474 } 1475 nilfs_truncate_logs(&sci->sc_segbufs, last); 1476 } 1477 1478 1479 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1480 struct the_nilfs *nilfs, int mode) 1481 { 1482 struct nilfs_cstage prev_stage = sci->sc_stage; 1483 int err, nadd = 1; 1484 1485 /* Collection retry loop */ 1486 for (;;) { 1487 sci->sc_nblk_this_inc = 0; 1488 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1489 1490 err = nilfs_segctor_reset_segment_buffer(sci); 1491 if (unlikely(err)) 1492 goto failed; 1493 1494 err = nilfs_segctor_collect_blocks(sci, mode); 1495 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1496 if (!err) 1497 break; 1498 1499 if (unlikely(err != -E2BIG)) 1500 goto failed; 1501 1502 /* The current segment is filled up */ 1503 if (mode != SC_LSEG_SR || 1504 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE) 1505 break; 1506 1507 nilfs_clear_logs(&sci->sc_segbufs); 1508 1509 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1510 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1511 sci->sc_freesegs, 1512 sci->sc_nfreesegs, 1513 NULL); 1514 WARN_ON(err); /* do not happen */ 1515 sci->sc_stage.flags &= ~NILFS_CF_SUFREED; 1516 } 1517 1518 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1519 if (unlikely(err)) 1520 return err; 1521 1522 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1523 sci->sc_stage = prev_stage; 1524 } 1525 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1526 return 0; 1527 1528 failed: 1529 return err; 1530 } 1531 1532 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1533 struct buffer_head *new_bh) 1534 { 1535 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1536 1537 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1538 /* The caller must release old_bh */ 1539 } 1540 1541 static int 1542 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1543 struct nilfs_segment_buffer *segbuf, 1544 int mode) 1545 { 1546 struct inode *inode = NULL; 1547 sector_t blocknr; 1548 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1549 unsigned long nblocks = 0, ndatablk = 0; 1550 const struct nilfs_sc_operations *sc_op = NULL; 1551 struct nilfs_segsum_pointer ssp; 1552 struct nilfs_finfo *finfo = NULL; 1553 union nilfs_binfo binfo; 1554 struct buffer_head *bh, *bh_org; 1555 ino_t ino = 0; 1556 int err = 0; 1557 1558 if (!nfinfo) 1559 goto out; 1560 1561 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1562 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1563 ssp.offset = sizeof(struct nilfs_segment_summary); 1564 1565 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1566 if (bh == segbuf->sb_super_root) 1567 break; 1568 if (!finfo) { 1569 finfo = nilfs_segctor_map_segsum_entry( 1570 sci, &ssp, sizeof(*finfo)); 1571 ino = le64_to_cpu(finfo->fi_ino); 1572 nblocks = le32_to_cpu(finfo->fi_nblocks); 1573 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1574 1575 inode = bh->b_page->mapping->host; 1576 1577 if (mode == SC_LSEG_DSYNC) 1578 sc_op = &nilfs_sc_dsync_ops; 1579 else if (ino == NILFS_DAT_INO) 1580 sc_op = &nilfs_sc_dat_ops; 1581 else /* file blocks */ 1582 sc_op = &nilfs_sc_file_ops; 1583 } 1584 bh_org = bh; 1585 get_bh(bh_org); 1586 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1587 &binfo); 1588 if (bh != bh_org) 1589 nilfs_list_replace_buffer(bh_org, bh); 1590 brelse(bh_org); 1591 if (unlikely(err)) 1592 goto failed_bmap; 1593 1594 if (ndatablk > 0) 1595 sc_op->write_data_binfo(sci, &ssp, &binfo); 1596 else 1597 sc_op->write_node_binfo(sci, &ssp, &binfo); 1598 1599 blocknr++; 1600 if (--nblocks == 0) { 1601 finfo = NULL; 1602 if (--nfinfo == 0) 1603 break; 1604 } else if (ndatablk > 0) 1605 ndatablk--; 1606 } 1607 out: 1608 return 0; 1609 1610 failed_bmap: 1611 return err; 1612 } 1613 1614 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1615 { 1616 struct nilfs_segment_buffer *segbuf; 1617 int err; 1618 1619 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1620 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1621 if (unlikely(err)) 1622 return err; 1623 nilfs_segbuf_fill_in_segsum(segbuf); 1624 } 1625 return 0; 1626 } 1627 1628 static void nilfs_begin_page_io(struct page *page) 1629 { 1630 if (!page || PageWriteback(page)) 1631 /* 1632 * For split b-tree node pages, this function may be called 1633 * twice. We ignore the 2nd or later calls by this check. 1634 */ 1635 return; 1636 1637 lock_page(page); 1638 clear_page_dirty_for_io(page); 1639 set_page_writeback(page); 1640 unlock_page(page); 1641 } 1642 1643 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci) 1644 { 1645 struct nilfs_segment_buffer *segbuf; 1646 struct page *bd_page = NULL, *fs_page = NULL; 1647 1648 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1649 struct buffer_head *bh; 1650 1651 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1652 b_assoc_buffers) { 1653 if (bh->b_page != bd_page) { 1654 if (bd_page) { 1655 lock_page(bd_page); 1656 clear_page_dirty_for_io(bd_page); 1657 set_page_writeback(bd_page); 1658 unlock_page(bd_page); 1659 } 1660 bd_page = bh->b_page; 1661 } 1662 } 1663 1664 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1665 b_assoc_buffers) { 1666 set_buffer_async_write(bh); 1667 if (bh == segbuf->sb_super_root) { 1668 if (bh->b_page != bd_page) { 1669 lock_page(bd_page); 1670 clear_page_dirty_for_io(bd_page); 1671 set_page_writeback(bd_page); 1672 unlock_page(bd_page); 1673 bd_page = bh->b_page; 1674 } 1675 break; 1676 } 1677 if (bh->b_page != fs_page) { 1678 nilfs_begin_page_io(fs_page); 1679 fs_page = bh->b_page; 1680 } 1681 } 1682 } 1683 if (bd_page) { 1684 lock_page(bd_page); 1685 clear_page_dirty_for_io(bd_page); 1686 set_page_writeback(bd_page); 1687 unlock_page(bd_page); 1688 } 1689 nilfs_begin_page_io(fs_page); 1690 } 1691 1692 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1693 struct the_nilfs *nilfs) 1694 { 1695 int ret; 1696 1697 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs); 1698 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs); 1699 return ret; 1700 } 1701 1702 static void nilfs_end_page_io(struct page *page, int err) 1703 { 1704 if (!page) 1705 return; 1706 1707 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) { 1708 /* 1709 * For b-tree node pages, this function may be called twice 1710 * or more because they might be split in a segment. 1711 */ 1712 if (PageDirty(page)) { 1713 /* 1714 * For pages holding split b-tree node buffers, dirty 1715 * flag on the buffers may be cleared discretely. 1716 * In that case, the page is once redirtied for 1717 * remaining buffers, and it must be cancelled if 1718 * all the buffers get cleaned later. 1719 */ 1720 lock_page(page); 1721 if (nilfs_page_buffers_clean(page)) 1722 __nilfs_clear_page_dirty(page); 1723 unlock_page(page); 1724 } 1725 return; 1726 } 1727 1728 if (!err) { 1729 if (!nilfs_page_buffers_clean(page)) 1730 __set_page_dirty_nobuffers(page); 1731 ClearPageError(page); 1732 } else { 1733 __set_page_dirty_nobuffers(page); 1734 SetPageError(page); 1735 } 1736 1737 end_page_writeback(page); 1738 } 1739 1740 static void nilfs_abort_logs(struct list_head *logs, int err) 1741 { 1742 struct nilfs_segment_buffer *segbuf; 1743 struct page *bd_page = NULL, *fs_page = NULL; 1744 struct buffer_head *bh; 1745 1746 if (list_empty(logs)) 1747 return; 1748 1749 list_for_each_entry(segbuf, logs, sb_list) { 1750 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1751 b_assoc_buffers) { 1752 if (bh->b_page != bd_page) { 1753 if (bd_page) 1754 end_page_writeback(bd_page); 1755 bd_page = bh->b_page; 1756 } 1757 } 1758 1759 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1760 b_assoc_buffers) { 1761 clear_buffer_async_write(bh); 1762 if (bh == segbuf->sb_super_root) { 1763 if (bh->b_page != bd_page) { 1764 end_page_writeback(bd_page); 1765 bd_page = bh->b_page; 1766 } 1767 break; 1768 } 1769 if (bh->b_page != fs_page) { 1770 nilfs_end_page_io(fs_page, err); 1771 fs_page = bh->b_page; 1772 } 1773 } 1774 } 1775 if (bd_page) 1776 end_page_writeback(bd_page); 1777 1778 nilfs_end_page_io(fs_page, err); 1779 } 1780 1781 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci, 1782 struct the_nilfs *nilfs, int err) 1783 { 1784 LIST_HEAD(logs); 1785 int ret; 1786 1787 list_splice_tail_init(&sci->sc_write_logs, &logs); 1788 ret = nilfs_wait_on_logs(&logs); 1789 nilfs_abort_logs(&logs, ret ? : err); 1790 1791 list_splice_tail_init(&sci->sc_segbufs, &logs); 1792 nilfs_cancel_segusage(&logs, nilfs->ns_sufile); 1793 nilfs_free_incomplete_logs(&logs, nilfs); 1794 1795 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1796 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1797 sci->sc_freesegs, 1798 sci->sc_nfreesegs, 1799 NULL); 1800 WARN_ON(ret); /* do not happen */ 1801 } 1802 1803 nilfs_destroy_logs(&logs); 1804 } 1805 1806 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1807 struct nilfs_segment_buffer *segbuf) 1808 { 1809 nilfs->ns_segnum = segbuf->sb_segnum; 1810 nilfs->ns_nextnum = segbuf->sb_nextnum; 1811 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1812 + segbuf->sb_sum.nblocks; 1813 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1814 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1815 } 1816 1817 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1818 { 1819 struct nilfs_segment_buffer *segbuf; 1820 struct page *bd_page = NULL, *fs_page = NULL; 1821 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1822 int update_sr = false; 1823 1824 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) { 1825 struct buffer_head *bh; 1826 1827 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1828 b_assoc_buffers) { 1829 set_buffer_uptodate(bh); 1830 clear_buffer_dirty(bh); 1831 if (bh->b_page != bd_page) { 1832 if (bd_page) 1833 end_page_writeback(bd_page); 1834 bd_page = bh->b_page; 1835 } 1836 } 1837 /* 1838 * We assume that the buffers which belong to the same page 1839 * continue over the buffer list. 1840 * Under this assumption, the last BHs of pages is 1841 * identifiable by the discontinuity of bh->b_page 1842 * (page != fs_page). 1843 * 1844 * For B-tree node blocks, however, this assumption is not 1845 * guaranteed. The cleanup code of B-tree node pages needs 1846 * special care. 1847 */ 1848 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1849 b_assoc_buffers) { 1850 const unsigned long set_bits = BIT(BH_Uptodate); 1851 const unsigned long clear_bits = 1852 (BIT(BH_Dirty) | BIT(BH_Async_Write) | 1853 BIT(BH_Delay) | BIT(BH_NILFS_Volatile) | 1854 BIT(BH_NILFS_Redirected)); 1855 1856 set_mask_bits(&bh->b_state, clear_bits, set_bits); 1857 if (bh == segbuf->sb_super_root) { 1858 if (bh->b_page != bd_page) { 1859 end_page_writeback(bd_page); 1860 bd_page = bh->b_page; 1861 } 1862 update_sr = true; 1863 break; 1864 } 1865 if (bh->b_page != fs_page) { 1866 nilfs_end_page_io(fs_page, 0); 1867 fs_page = bh->b_page; 1868 } 1869 } 1870 1871 if (!nilfs_segbuf_simplex(segbuf)) { 1872 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) { 1873 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1874 sci->sc_lseg_stime = jiffies; 1875 } 1876 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND) 1877 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1878 } 1879 } 1880 /* 1881 * Since pages may continue over multiple segment buffers, 1882 * end of the last page must be checked outside of the loop. 1883 */ 1884 if (bd_page) 1885 end_page_writeback(bd_page); 1886 1887 nilfs_end_page_io(fs_page, 0); 1888 1889 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 1890 1891 if (nilfs_doing_gc()) 1892 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 1893 else 1894 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 1895 1896 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 1897 1898 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1899 nilfs_set_next_segment(nilfs, segbuf); 1900 1901 if (update_sr) { 1902 nilfs->ns_flushed_device = 0; 1903 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 1904 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 1905 1906 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 1907 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 1908 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1909 nilfs_segctor_clear_metadata_dirty(sci); 1910 } else 1911 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1912 } 1913 1914 static int nilfs_segctor_wait(struct nilfs_sc_info *sci) 1915 { 1916 int ret; 1917 1918 ret = nilfs_wait_on_logs(&sci->sc_write_logs); 1919 if (!ret) { 1920 nilfs_segctor_complete_write(sci); 1921 nilfs_destroy_logs(&sci->sc_write_logs); 1922 } 1923 return ret; 1924 } 1925 1926 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci, 1927 struct the_nilfs *nilfs) 1928 { 1929 struct nilfs_inode_info *ii, *n; 1930 struct inode *ifile = sci->sc_root->ifile; 1931 1932 spin_lock(&nilfs->ns_inode_lock); 1933 retry: 1934 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) { 1935 if (!ii->i_bh) { 1936 struct buffer_head *ibh; 1937 int err; 1938 1939 spin_unlock(&nilfs->ns_inode_lock); 1940 err = nilfs_ifile_get_inode_block( 1941 ifile, ii->vfs_inode.i_ino, &ibh); 1942 if (unlikely(err)) { 1943 nilfs_warn(sci->sc_super, 1944 "log writer: error %d getting inode block (ino=%lu)", 1945 err, ii->vfs_inode.i_ino); 1946 return err; 1947 } 1948 spin_lock(&nilfs->ns_inode_lock); 1949 if (likely(!ii->i_bh)) 1950 ii->i_bh = ibh; 1951 else 1952 brelse(ibh); 1953 goto retry; 1954 } 1955 1956 // Always redirty the buffer to avoid race condition 1957 mark_buffer_dirty(ii->i_bh); 1958 nilfs_mdt_mark_dirty(ifile); 1959 1960 clear_bit(NILFS_I_QUEUED, &ii->i_state); 1961 set_bit(NILFS_I_BUSY, &ii->i_state); 1962 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files); 1963 } 1964 spin_unlock(&nilfs->ns_inode_lock); 1965 1966 return 0; 1967 } 1968 1969 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci, 1970 struct the_nilfs *nilfs) 1971 { 1972 struct nilfs_inode_info *ii, *n; 1973 int during_mount = !(sci->sc_super->s_flags & SB_ACTIVE); 1974 int defer_iput = false; 1975 1976 spin_lock(&nilfs->ns_inode_lock); 1977 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 1978 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 1979 test_bit(NILFS_I_DIRTY, &ii->i_state)) 1980 continue; 1981 1982 clear_bit(NILFS_I_BUSY, &ii->i_state); 1983 brelse(ii->i_bh); 1984 ii->i_bh = NULL; 1985 list_del_init(&ii->i_dirty); 1986 if (!ii->vfs_inode.i_nlink || during_mount) { 1987 /* 1988 * Defer calling iput() to avoid deadlocks if 1989 * i_nlink == 0 or mount is not yet finished. 1990 */ 1991 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue); 1992 defer_iput = true; 1993 } else { 1994 spin_unlock(&nilfs->ns_inode_lock); 1995 iput(&ii->vfs_inode); 1996 spin_lock(&nilfs->ns_inode_lock); 1997 } 1998 } 1999 spin_unlock(&nilfs->ns_inode_lock); 2000 2001 if (defer_iput) 2002 schedule_work(&sci->sc_iput_work); 2003 } 2004 2005 /* 2006 * Main procedure of segment constructor 2007 */ 2008 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 2009 { 2010 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2011 int err; 2012 2013 nilfs_sc_cstage_set(sci, NILFS_ST_INIT); 2014 sci->sc_cno = nilfs->ns_cno; 2015 2016 err = nilfs_segctor_collect_dirty_files(sci, nilfs); 2017 if (unlikely(err)) 2018 goto out; 2019 2020 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 2021 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2022 2023 if (nilfs_segctor_clean(sci)) 2024 goto out; 2025 2026 do { 2027 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 2028 2029 err = nilfs_segctor_begin_construction(sci, nilfs); 2030 if (unlikely(err)) 2031 goto out; 2032 2033 /* Update time stamp */ 2034 sci->sc_seg_ctime = ktime_get_real_seconds(); 2035 2036 err = nilfs_segctor_collect(sci, nilfs, mode); 2037 if (unlikely(err)) 2038 goto failed; 2039 2040 /* Avoid empty segment */ 2041 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE && 2042 nilfs_segbuf_empty(sci->sc_curseg)) { 2043 nilfs_segctor_abort_construction(sci, nilfs, 1); 2044 goto out; 2045 } 2046 2047 err = nilfs_segctor_assign(sci, mode); 2048 if (unlikely(err)) 2049 goto failed; 2050 2051 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2052 nilfs_segctor_fill_in_file_bmap(sci); 2053 2054 if (mode == SC_LSEG_SR && 2055 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) { 2056 err = nilfs_segctor_fill_in_checkpoint(sci); 2057 if (unlikely(err)) 2058 goto failed_to_write; 2059 2060 nilfs_segctor_fill_in_super_root(sci, nilfs); 2061 } 2062 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 2063 2064 /* Write partial segments */ 2065 nilfs_segctor_prepare_write(sci); 2066 2067 nilfs_add_checksums_on_logs(&sci->sc_segbufs, 2068 nilfs->ns_crc_seed); 2069 2070 err = nilfs_segctor_write(sci, nilfs); 2071 if (unlikely(err)) 2072 goto failed_to_write; 2073 2074 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE || 2075 nilfs->ns_blocksize_bits != PAGE_SHIFT) { 2076 /* 2077 * At this point, we avoid double buffering 2078 * for blocksize < pagesize because page dirty 2079 * flag is turned off during write and dirty 2080 * buffers are not properly collected for 2081 * pages crossing over segments. 2082 */ 2083 err = nilfs_segctor_wait(sci); 2084 if (err) 2085 goto failed_to_write; 2086 } 2087 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE); 2088 2089 out: 2090 nilfs_segctor_drop_written_files(sci, nilfs); 2091 return err; 2092 2093 failed_to_write: 2094 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2095 nilfs_redirty_inodes(&sci->sc_dirty_files); 2096 2097 failed: 2098 if (nilfs_doing_gc()) 2099 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2100 nilfs_segctor_abort_construction(sci, nilfs, err); 2101 goto out; 2102 } 2103 2104 /** 2105 * nilfs_segctor_start_timer - set timer of background write 2106 * @sci: nilfs_sc_info 2107 * 2108 * If the timer has already been set, it ignores the new request. 2109 * This function MUST be called within a section locking the segment 2110 * semaphore. 2111 */ 2112 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2113 { 2114 spin_lock(&sci->sc_state_lock); 2115 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2116 sci->sc_timer.expires = jiffies + sci->sc_interval; 2117 add_timer(&sci->sc_timer); 2118 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2119 } 2120 spin_unlock(&sci->sc_state_lock); 2121 } 2122 2123 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2124 { 2125 spin_lock(&sci->sc_state_lock); 2126 if (!(sci->sc_flush_request & BIT(bn))) { 2127 unsigned long prev_req = sci->sc_flush_request; 2128 2129 sci->sc_flush_request |= BIT(bn); 2130 if (!prev_req) 2131 wake_up(&sci->sc_wait_daemon); 2132 } 2133 spin_unlock(&sci->sc_state_lock); 2134 } 2135 2136 /** 2137 * nilfs_flush_segment - trigger a segment construction for resource control 2138 * @sb: super block 2139 * @ino: inode number of the file to be flushed out. 2140 */ 2141 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2142 { 2143 struct the_nilfs *nilfs = sb->s_fs_info; 2144 struct nilfs_sc_info *sci = nilfs->ns_writer; 2145 2146 if (!sci || nilfs_doing_construction()) 2147 return; 2148 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2149 /* assign bit 0 to data files */ 2150 } 2151 2152 struct nilfs_segctor_wait_request { 2153 wait_queue_entry_t wq; 2154 __u32 seq; 2155 int err; 2156 atomic_t done; 2157 }; 2158 2159 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2160 { 2161 struct nilfs_segctor_wait_request wait_req; 2162 int err = 0; 2163 2164 spin_lock(&sci->sc_state_lock); 2165 init_wait(&wait_req.wq); 2166 wait_req.err = 0; 2167 atomic_set(&wait_req.done, 0); 2168 wait_req.seq = ++sci->sc_seq_request; 2169 spin_unlock(&sci->sc_state_lock); 2170 2171 init_waitqueue_entry(&wait_req.wq, current); 2172 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2173 set_current_state(TASK_INTERRUPTIBLE); 2174 wake_up(&sci->sc_wait_daemon); 2175 2176 for (;;) { 2177 if (atomic_read(&wait_req.done)) { 2178 err = wait_req.err; 2179 break; 2180 } 2181 if (!signal_pending(current)) { 2182 schedule(); 2183 continue; 2184 } 2185 err = -ERESTARTSYS; 2186 break; 2187 } 2188 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2189 return err; 2190 } 2191 2192 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2193 { 2194 struct nilfs_segctor_wait_request *wrq, *n; 2195 unsigned long flags; 2196 2197 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2198 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.head, wq.entry) { 2199 if (!atomic_read(&wrq->done) && 2200 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { 2201 wrq->err = err; 2202 atomic_set(&wrq->done, 1); 2203 } 2204 if (atomic_read(&wrq->done)) { 2205 wrq->wq.func(&wrq->wq, 2206 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 2207 0, NULL); 2208 } 2209 } 2210 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); 2211 } 2212 2213 /** 2214 * nilfs_construct_segment - construct a logical segment 2215 * @sb: super block 2216 * 2217 * Return Value: On success, 0 is returned. On errors, one of the following 2218 * negative error code is returned. 2219 * 2220 * %-EROFS - Read only filesystem. 2221 * 2222 * %-EIO - I/O error 2223 * 2224 * %-ENOSPC - No space left on device (only in a panic state). 2225 * 2226 * %-ERESTARTSYS - Interrupted. 2227 * 2228 * %-ENOMEM - Insufficient memory available. 2229 */ 2230 int nilfs_construct_segment(struct super_block *sb) 2231 { 2232 struct the_nilfs *nilfs = sb->s_fs_info; 2233 struct nilfs_sc_info *sci = nilfs->ns_writer; 2234 struct nilfs_transaction_info *ti; 2235 int err; 2236 2237 if (!sci) 2238 return -EROFS; 2239 2240 /* A call inside transactions causes a deadlock. */ 2241 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); 2242 2243 err = nilfs_segctor_sync(sci); 2244 return err; 2245 } 2246 2247 /** 2248 * nilfs_construct_dsync_segment - construct a data-only logical segment 2249 * @sb: super block 2250 * @inode: inode whose data blocks should be written out 2251 * @start: start byte offset 2252 * @end: end byte offset (inclusive) 2253 * 2254 * Return Value: On success, 0 is returned. On errors, one of the following 2255 * negative error code is returned. 2256 * 2257 * %-EROFS - Read only filesystem. 2258 * 2259 * %-EIO - I/O error 2260 * 2261 * %-ENOSPC - No space left on device (only in a panic state). 2262 * 2263 * %-ERESTARTSYS - Interrupted. 2264 * 2265 * %-ENOMEM - Insufficient memory available. 2266 */ 2267 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 2268 loff_t start, loff_t end) 2269 { 2270 struct the_nilfs *nilfs = sb->s_fs_info; 2271 struct nilfs_sc_info *sci = nilfs->ns_writer; 2272 struct nilfs_inode_info *ii; 2273 struct nilfs_transaction_info ti; 2274 int err = 0; 2275 2276 if (!sci) 2277 return -EROFS; 2278 2279 nilfs_transaction_lock(sb, &ti, 0); 2280 2281 ii = NILFS_I(inode); 2282 if (test_bit(NILFS_I_INODE_SYNC, &ii->i_state) || 2283 nilfs_test_opt(nilfs, STRICT_ORDER) || 2284 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2285 nilfs_discontinued(nilfs)) { 2286 nilfs_transaction_unlock(sb); 2287 err = nilfs_segctor_sync(sci); 2288 return err; 2289 } 2290 2291 spin_lock(&nilfs->ns_inode_lock); 2292 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && 2293 !test_bit(NILFS_I_BUSY, &ii->i_state)) { 2294 spin_unlock(&nilfs->ns_inode_lock); 2295 nilfs_transaction_unlock(sb); 2296 return 0; 2297 } 2298 spin_unlock(&nilfs->ns_inode_lock); 2299 sci->sc_dsync_inode = ii; 2300 sci->sc_dsync_start = start; 2301 sci->sc_dsync_end = end; 2302 2303 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); 2304 if (!err) 2305 nilfs->ns_flushed_device = 0; 2306 2307 nilfs_transaction_unlock(sb); 2308 return err; 2309 } 2310 2311 #define FLUSH_FILE_BIT (0x1) /* data file only */ 2312 #define FLUSH_DAT_BIT BIT(NILFS_DAT_INO) /* DAT only */ 2313 2314 /** 2315 * nilfs_segctor_accept - record accepted sequence count of log-write requests 2316 * @sci: segment constructor object 2317 */ 2318 static void nilfs_segctor_accept(struct nilfs_sc_info *sci) 2319 { 2320 spin_lock(&sci->sc_state_lock); 2321 sci->sc_seq_accepted = sci->sc_seq_request; 2322 spin_unlock(&sci->sc_state_lock); 2323 del_timer_sync(&sci->sc_timer); 2324 } 2325 2326 /** 2327 * nilfs_segctor_notify - notify the result of request to caller threads 2328 * @sci: segment constructor object 2329 * @mode: mode of log forming 2330 * @err: error code to be notified 2331 */ 2332 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) 2333 { 2334 /* Clear requests (even when the construction failed) */ 2335 spin_lock(&sci->sc_state_lock); 2336 2337 if (mode == SC_LSEG_SR) { 2338 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; 2339 sci->sc_seq_done = sci->sc_seq_accepted; 2340 nilfs_segctor_wakeup(sci, err); 2341 sci->sc_flush_request = 0; 2342 } else { 2343 if (mode == SC_FLUSH_FILE) 2344 sci->sc_flush_request &= ~FLUSH_FILE_BIT; 2345 else if (mode == SC_FLUSH_DAT) 2346 sci->sc_flush_request &= ~FLUSH_DAT_BIT; 2347 2348 /* re-enable timer if checkpoint creation was not done */ 2349 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2350 time_before(jiffies, sci->sc_timer.expires)) 2351 add_timer(&sci->sc_timer); 2352 } 2353 spin_unlock(&sci->sc_state_lock); 2354 } 2355 2356 /** 2357 * nilfs_segctor_construct - form logs and write them to disk 2358 * @sci: segment constructor object 2359 * @mode: mode of log forming 2360 */ 2361 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode) 2362 { 2363 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2364 struct nilfs_super_block **sbp; 2365 int err = 0; 2366 2367 nilfs_segctor_accept(sci); 2368 2369 if (nilfs_discontinued(nilfs)) 2370 mode = SC_LSEG_SR; 2371 if (!nilfs_segctor_confirm(sci)) 2372 err = nilfs_segctor_do_construct(sci, mode); 2373 2374 if (likely(!err)) { 2375 if (mode != SC_FLUSH_DAT) 2376 atomic_set(&nilfs->ns_ndirtyblks, 0); 2377 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && 2378 nilfs_discontinued(nilfs)) { 2379 down_write(&nilfs->ns_sem); 2380 err = -EIO; 2381 sbp = nilfs_prepare_super(sci->sc_super, 2382 nilfs_sb_will_flip(nilfs)); 2383 if (likely(sbp)) { 2384 nilfs_set_log_cursor(sbp[0], nilfs); 2385 err = nilfs_commit_super(sci->sc_super, 2386 NILFS_SB_COMMIT); 2387 } 2388 up_write(&nilfs->ns_sem); 2389 } 2390 } 2391 2392 nilfs_segctor_notify(sci, mode, err); 2393 return err; 2394 } 2395 2396 static void nilfs_construction_timeout(struct timer_list *t) 2397 { 2398 struct nilfs_sc_info *sci = from_timer(sci, t, sc_timer); 2399 2400 wake_up_process(sci->sc_timer_task); 2401 } 2402 2403 static void 2404 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) 2405 { 2406 struct nilfs_inode_info *ii, *n; 2407 2408 list_for_each_entry_safe(ii, n, head, i_dirty) { 2409 if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) 2410 continue; 2411 list_del_init(&ii->i_dirty); 2412 truncate_inode_pages(&ii->vfs_inode.i_data, 0); 2413 nilfs_btnode_cache_clear(&ii->i_btnode_cache); 2414 iput(&ii->vfs_inode); 2415 } 2416 } 2417 2418 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, 2419 void **kbufs) 2420 { 2421 struct the_nilfs *nilfs = sb->s_fs_info; 2422 struct nilfs_sc_info *sci = nilfs->ns_writer; 2423 struct nilfs_transaction_info ti; 2424 int err; 2425 2426 if (unlikely(!sci)) 2427 return -EROFS; 2428 2429 nilfs_transaction_lock(sb, &ti, 1); 2430 2431 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat); 2432 if (unlikely(err)) 2433 goto out_unlock; 2434 2435 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs); 2436 if (unlikely(err)) { 2437 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat); 2438 goto out_unlock; 2439 } 2440 2441 sci->sc_freesegs = kbufs[4]; 2442 sci->sc_nfreesegs = argv[4].v_nmembs; 2443 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes); 2444 2445 for (;;) { 2446 err = nilfs_segctor_construct(sci, SC_LSEG_SR); 2447 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); 2448 2449 if (likely(!err)) 2450 break; 2451 2452 nilfs_warn(sb, "error %d cleaning segments", err); 2453 set_current_state(TASK_INTERRUPTIBLE); 2454 schedule_timeout(sci->sc_interval); 2455 } 2456 if (nilfs_test_opt(nilfs, DISCARD)) { 2457 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, 2458 sci->sc_nfreesegs); 2459 if (ret) { 2460 nilfs_warn(sb, 2461 "error %d on discard request, turning discards off for the device", 2462 ret); 2463 nilfs_clear_opt(nilfs, DISCARD); 2464 } 2465 } 2466 2467 out_unlock: 2468 sci->sc_freesegs = NULL; 2469 sci->sc_nfreesegs = 0; 2470 nilfs_mdt_clear_shadow_map(nilfs->ns_dat); 2471 nilfs_transaction_unlock(sb); 2472 return err; 2473 } 2474 2475 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2476 { 2477 struct nilfs_transaction_info ti; 2478 2479 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2480 nilfs_segctor_construct(sci, mode); 2481 2482 /* 2483 * Unclosed segment should be retried. We do this using sc_timer. 2484 * Timeout of sc_timer will invoke complete construction which leads 2485 * to close the current logical segment. 2486 */ 2487 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2488 nilfs_segctor_start_timer(sci); 2489 2490 nilfs_transaction_unlock(sci->sc_super); 2491 } 2492 2493 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2494 { 2495 int mode = 0; 2496 2497 spin_lock(&sci->sc_state_lock); 2498 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2499 SC_FLUSH_DAT : SC_FLUSH_FILE; 2500 spin_unlock(&sci->sc_state_lock); 2501 2502 if (mode) { 2503 nilfs_segctor_do_construct(sci, mode); 2504 2505 spin_lock(&sci->sc_state_lock); 2506 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2507 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2508 spin_unlock(&sci->sc_state_lock); 2509 } 2510 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2511 } 2512 2513 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2514 { 2515 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2516 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2517 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2518 return SC_FLUSH_FILE; 2519 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2520 return SC_FLUSH_DAT; 2521 } 2522 return SC_LSEG_SR; 2523 } 2524 2525 /** 2526 * nilfs_segctor_thread - main loop of the segment constructor thread. 2527 * @arg: pointer to a struct nilfs_sc_info. 2528 * 2529 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2530 * to execute segment constructions. 2531 */ 2532 static int nilfs_segctor_thread(void *arg) 2533 { 2534 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2535 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2536 int timeout = 0; 2537 2538 sci->sc_timer_task = current; 2539 2540 /* start sync. */ 2541 sci->sc_task = current; 2542 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2543 nilfs_info(sci->sc_super, 2544 "segctord starting. Construction interval = %lu seconds, CP frequency < %lu seconds", 2545 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2546 2547 spin_lock(&sci->sc_state_lock); 2548 loop: 2549 for (;;) { 2550 int mode; 2551 2552 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2553 goto end_thread; 2554 2555 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2556 mode = SC_LSEG_SR; 2557 else if (sci->sc_flush_request) 2558 mode = nilfs_segctor_flush_mode(sci); 2559 else 2560 break; 2561 2562 spin_unlock(&sci->sc_state_lock); 2563 nilfs_segctor_thread_construct(sci, mode); 2564 spin_lock(&sci->sc_state_lock); 2565 timeout = 0; 2566 } 2567 2568 2569 if (freezing(current)) { 2570 spin_unlock(&sci->sc_state_lock); 2571 try_to_freeze(); 2572 spin_lock(&sci->sc_state_lock); 2573 } else { 2574 DEFINE_WAIT(wait); 2575 int should_sleep = 1; 2576 2577 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2578 TASK_INTERRUPTIBLE); 2579 2580 if (sci->sc_seq_request != sci->sc_seq_done) 2581 should_sleep = 0; 2582 else if (sci->sc_flush_request) 2583 should_sleep = 0; 2584 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2585 should_sleep = time_before(jiffies, 2586 sci->sc_timer.expires); 2587 2588 if (should_sleep) { 2589 spin_unlock(&sci->sc_state_lock); 2590 schedule(); 2591 spin_lock(&sci->sc_state_lock); 2592 } 2593 finish_wait(&sci->sc_wait_daemon, &wait); 2594 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2595 time_after_eq(jiffies, sci->sc_timer.expires)); 2596 2597 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) 2598 set_nilfs_discontinued(nilfs); 2599 } 2600 goto loop; 2601 2602 end_thread: 2603 spin_unlock(&sci->sc_state_lock); 2604 2605 /* end sync. */ 2606 sci->sc_task = NULL; 2607 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2608 return 0; 2609 } 2610 2611 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2612 { 2613 struct task_struct *t; 2614 2615 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2616 if (IS_ERR(t)) { 2617 int err = PTR_ERR(t); 2618 2619 nilfs_err(sci->sc_super, "error %d creating segctord thread", 2620 err); 2621 return err; 2622 } 2623 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2624 return 0; 2625 } 2626 2627 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2628 __acquires(&sci->sc_state_lock) 2629 __releases(&sci->sc_state_lock) 2630 { 2631 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2632 2633 while (sci->sc_task) { 2634 wake_up(&sci->sc_wait_daemon); 2635 spin_unlock(&sci->sc_state_lock); 2636 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2637 spin_lock(&sci->sc_state_lock); 2638 } 2639 } 2640 2641 /* 2642 * Setup & clean-up functions 2643 */ 2644 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb, 2645 struct nilfs_root *root) 2646 { 2647 struct the_nilfs *nilfs = sb->s_fs_info; 2648 struct nilfs_sc_info *sci; 2649 2650 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2651 if (!sci) 2652 return NULL; 2653 2654 sci->sc_super = sb; 2655 2656 nilfs_get_root(root); 2657 sci->sc_root = root; 2658 2659 init_waitqueue_head(&sci->sc_wait_request); 2660 init_waitqueue_head(&sci->sc_wait_daemon); 2661 init_waitqueue_head(&sci->sc_wait_task); 2662 spin_lock_init(&sci->sc_state_lock); 2663 INIT_LIST_HEAD(&sci->sc_dirty_files); 2664 INIT_LIST_HEAD(&sci->sc_segbufs); 2665 INIT_LIST_HEAD(&sci->sc_write_logs); 2666 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2667 INIT_LIST_HEAD(&sci->sc_iput_queue); 2668 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func); 2669 timer_setup(&sci->sc_timer, nilfs_construction_timeout, 0); 2670 2671 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2672 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2673 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2674 2675 if (nilfs->ns_interval) 2676 sci->sc_interval = HZ * nilfs->ns_interval; 2677 if (nilfs->ns_watermark) 2678 sci->sc_watermark = nilfs->ns_watermark; 2679 return sci; 2680 } 2681 2682 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2683 { 2684 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2685 2686 /* 2687 * The segctord thread was stopped and its timer was removed. 2688 * But some tasks remain. 2689 */ 2690 do { 2691 struct nilfs_transaction_info ti; 2692 2693 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2694 ret = nilfs_segctor_construct(sci, SC_LSEG_SR); 2695 nilfs_transaction_unlock(sci->sc_super); 2696 2697 flush_work(&sci->sc_iput_work); 2698 2699 } while (ret && retrycount-- > 0); 2700 } 2701 2702 /** 2703 * nilfs_segctor_destroy - destroy the segment constructor. 2704 * @sci: nilfs_sc_info 2705 * 2706 * nilfs_segctor_destroy() kills the segctord thread and frees 2707 * the nilfs_sc_info struct. 2708 * Caller must hold the segment semaphore. 2709 */ 2710 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2711 { 2712 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2713 int flag; 2714 2715 up_write(&nilfs->ns_segctor_sem); 2716 2717 spin_lock(&sci->sc_state_lock); 2718 nilfs_segctor_kill_thread(sci); 2719 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2720 || sci->sc_seq_request != sci->sc_seq_done); 2721 spin_unlock(&sci->sc_state_lock); 2722 2723 if (flush_work(&sci->sc_iput_work)) 2724 flag = true; 2725 2726 if (flag || !nilfs_segctor_confirm(sci)) 2727 nilfs_segctor_write_out(sci); 2728 2729 if (!list_empty(&sci->sc_dirty_files)) { 2730 nilfs_warn(sci->sc_super, 2731 "disposed unprocessed dirty file(s) when stopping log writer"); 2732 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1); 2733 } 2734 2735 if (!list_empty(&sci->sc_iput_queue)) { 2736 nilfs_warn(sci->sc_super, 2737 "disposed unprocessed inode(s) in iput queue when stopping log writer"); 2738 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1); 2739 } 2740 2741 WARN_ON(!list_empty(&sci->sc_segbufs)); 2742 WARN_ON(!list_empty(&sci->sc_write_logs)); 2743 2744 nilfs_put_root(sci->sc_root); 2745 2746 down_write(&nilfs->ns_segctor_sem); 2747 2748 del_timer_sync(&sci->sc_timer); 2749 kfree(sci); 2750 } 2751 2752 /** 2753 * nilfs_attach_log_writer - attach log writer 2754 * @sb: super block instance 2755 * @root: root object of the current filesystem tree 2756 * 2757 * This allocates a log writer object, initializes it, and starts the 2758 * log writer. 2759 * 2760 * Return Value: On success, 0 is returned. On error, one of the following 2761 * negative error code is returned. 2762 * 2763 * %-ENOMEM - Insufficient memory available. 2764 */ 2765 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root) 2766 { 2767 struct the_nilfs *nilfs = sb->s_fs_info; 2768 int err; 2769 2770 if (nilfs->ns_writer) { 2771 /* 2772 * This happens if the filesystem was remounted 2773 * read/write after nilfs_error degenerated it into a 2774 * read-only mount. 2775 */ 2776 nilfs_detach_log_writer(sb); 2777 } 2778 2779 nilfs->ns_writer = nilfs_segctor_new(sb, root); 2780 if (!nilfs->ns_writer) 2781 return -ENOMEM; 2782 2783 inode_attach_wb(nilfs->ns_bdev->bd_inode, NULL); 2784 2785 err = nilfs_segctor_start_thread(nilfs->ns_writer); 2786 if (err) { 2787 kfree(nilfs->ns_writer); 2788 nilfs->ns_writer = NULL; 2789 } 2790 return err; 2791 } 2792 2793 /** 2794 * nilfs_detach_log_writer - destroy log writer 2795 * @sb: super block instance 2796 * 2797 * This kills log writer daemon, frees the log writer object, and 2798 * destroys list of dirty files. 2799 */ 2800 void nilfs_detach_log_writer(struct super_block *sb) 2801 { 2802 struct the_nilfs *nilfs = sb->s_fs_info; 2803 LIST_HEAD(garbage_list); 2804 2805 down_write(&nilfs->ns_segctor_sem); 2806 if (nilfs->ns_writer) { 2807 nilfs_segctor_destroy(nilfs->ns_writer); 2808 nilfs->ns_writer = NULL; 2809 } 2810 2811 /* Force to free the list of dirty files */ 2812 spin_lock(&nilfs->ns_inode_lock); 2813 if (!list_empty(&nilfs->ns_dirty_files)) { 2814 list_splice_init(&nilfs->ns_dirty_files, &garbage_list); 2815 nilfs_warn(sb, 2816 "disposed unprocessed dirty file(s) when detaching log writer"); 2817 } 2818 spin_unlock(&nilfs->ns_inode_lock); 2819 up_write(&nilfs->ns_segctor_sem); 2820 2821 nilfs_dispose_list(nilfs, &garbage_list, 1); 2822 } 2823