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 "nilfs.h" 34 #include "btnode.h" 35 #include "page.h" 36 #include "segment.h" 37 #include "sufile.h" 38 #include "cpfile.h" 39 #include "ifile.h" 40 #include "segbuf.h" 41 42 43 /* 44 * Segment constructor 45 */ 46 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */ 47 48 #define SC_MAX_SEGDELTA 64 /* 49 * Upper limit of the number of segments 50 * appended in collection retry loop 51 */ 52 53 /* Construction mode */ 54 enum { 55 SC_LSEG_SR = 1, /* Make a logical segment having a super root */ 56 SC_LSEG_DSYNC, /* 57 * Flush data blocks of a given file and make 58 * a logical segment without a super root. 59 */ 60 SC_FLUSH_FILE, /* 61 * Flush data files, leads to segment writes without 62 * creating a checkpoint. 63 */ 64 SC_FLUSH_DAT, /* 65 * Flush DAT file. This also creates segments 66 * without a checkpoint. 67 */ 68 }; 69 70 /* Stage numbers of dirty block collection */ 71 enum { 72 NILFS_ST_INIT = 0, 73 NILFS_ST_GC, /* Collecting dirty blocks for GC */ 74 NILFS_ST_FILE, 75 NILFS_ST_IFILE, 76 NILFS_ST_CPFILE, 77 NILFS_ST_SUFILE, 78 NILFS_ST_DAT, 79 NILFS_ST_SR, /* Super root */ 80 NILFS_ST_DSYNC, /* Data sync blocks */ 81 NILFS_ST_DONE, 82 }; 83 84 #define CREATE_TRACE_POINTS 85 #include <trace/events/nilfs2.h> 86 87 /* 88 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() are 89 * wrapper functions of stage count (nilfs_sc_info->sc_stage.scnt). Users of 90 * the variable must use them because transition of stage count must involve 91 * trace events (trace_nilfs2_collection_stage_transition). 92 * 93 * nilfs_sc_cstage_get() isn't required for the above purpose because it doesn't 94 * produce tracepoint events. It is provided just for making the intention 95 * clear. 96 */ 97 static inline void nilfs_sc_cstage_inc(struct nilfs_sc_info *sci) 98 { 99 sci->sc_stage.scnt++; 100 trace_nilfs2_collection_stage_transition(sci); 101 } 102 103 static inline void nilfs_sc_cstage_set(struct nilfs_sc_info *sci, int next_scnt) 104 { 105 sci->sc_stage.scnt = next_scnt; 106 trace_nilfs2_collection_stage_transition(sci); 107 } 108 109 static inline int nilfs_sc_cstage_get(struct nilfs_sc_info *sci) 110 { 111 return sci->sc_stage.scnt; 112 } 113 114 /* State flags of collection */ 115 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ 116 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ 117 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */ 118 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED) 119 120 /* Operations depending on the construction mode and file type */ 121 struct nilfs_sc_operations { 122 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, 123 struct inode *); 124 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, 125 struct inode *); 126 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, 127 struct inode *); 128 void (*write_data_binfo)(struct nilfs_sc_info *, 129 struct nilfs_segsum_pointer *, 130 union nilfs_binfo *); 131 void (*write_node_binfo)(struct nilfs_sc_info *, 132 struct nilfs_segsum_pointer *, 133 union nilfs_binfo *); 134 }; 135 136 /* 137 * Other definitions 138 */ 139 static void nilfs_segctor_start_timer(struct nilfs_sc_info *); 140 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); 141 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); 142 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int); 143 144 #define nilfs_cnt32_gt(a, b) \ 145 (typecheck(__u32, a) && typecheck(__u32, b) && \ 146 ((__s32)(b) - (__s32)(a) < 0)) 147 #define nilfs_cnt32_ge(a, b) \ 148 (typecheck(__u32, a) && typecheck(__u32, b) && \ 149 ((__s32)(a) - (__s32)(b) >= 0)) 150 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a) 151 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a) 152 153 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti) 154 { 155 struct nilfs_transaction_info *cur_ti = current->journal_info; 156 void *save = NULL; 157 158 if (cur_ti) { 159 if (cur_ti->ti_magic == NILFS_TI_MAGIC) 160 return ++cur_ti->ti_count; 161 162 /* 163 * If journal_info field is occupied by other FS, 164 * it is saved and will be restored on 165 * nilfs_transaction_commit(). 166 */ 167 printk(KERN_WARNING 168 "NILFS warning: journal info from a different FS\n"); 169 save = current->journal_info; 170 } 171 if (!ti) { 172 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); 173 if (!ti) 174 return -ENOMEM; 175 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; 176 } else { 177 ti->ti_flags = 0; 178 } 179 ti->ti_count = 0; 180 ti->ti_save = save; 181 ti->ti_magic = NILFS_TI_MAGIC; 182 current->journal_info = ti; 183 return 0; 184 } 185 186 /** 187 * nilfs_transaction_begin - start indivisible file operations. 188 * @sb: super block 189 * @ti: nilfs_transaction_info 190 * @vacancy_check: flags for vacancy rate checks 191 * 192 * nilfs_transaction_begin() acquires a reader/writer semaphore, called 193 * the segment semaphore, to make a segment construction and write tasks 194 * exclusive. The function is used with nilfs_transaction_commit() in pairs. 195 * The region enclosed by these two functions can be nested. To avoid a 196 * deadlock, the semaphore is only acquired or released in the outermost call. 197 * 198 * This function allocates a nilfs_transaction_info struct to keep context 199 * information on it. It is initialized and hooked onto the current task in 200 * the outermost call. If a pre-allocated struct is given to @ti, it is used 201 * instead; otherwise a new struct is assigned from a slab. 202 * 203 * When @vacancy_check flag is set, this function will check the amount of 204 * free space, and will wait for the GC to reclaim disk space if low capacity. 205 * 206 * Return Value: On success, 0 is returned. On error, one of the following 207 * negative error code is returned. 208 * 209 * %-ENOMEM - Insufficient memory available. 210 * 211 * %-ENOSPC - No space left on device 212 */ 213 int nilfs_transaction_begin(struct super_block *sb, 214 struct nilfs_transaction_info *ti, 215 int vacancy_check) 216 { 217 struct the_nilfs *nilfs; 218 int ret = nilfs_prepare_segment_lock(ti); 219 struct nilfs_transaction_info *trace_ti; 220 221 if (unlikely(ret < 0)) 222 return ret; 223 if (ret > 0) { 224 trace_ti = current->journal_info; 225 226 trace_nilfs2_transaction_transition(sb, trace_ti, 227 trace_ti->ti_count, trace_ti->ti_flags, 228 TRACE_NILFS2_TRANSACTION_BEGIN); 229 return 0; 230 } 231 232 sb_start_intwrite(sb); 233 234 nilfs = sb->s_fs_info; 235 down_read(&nilfs->ns_segctor_sem); 236 if (vacancy_check && nilfs_near_disk_full(nilfs)) { 237 up_read(&nilfs->ns_segctor_sem); 238 ret = -ENOSPC; 239 goto failed; 240 } 241 242 trace_ti = current->journal_info; 243 trace_nilfs2_transaction_transition(sb, trace_ti, trace_ti->ti_count, 244 trace_ti->ti_flags, 245 TRACE_NILFS2_TRANSACTION_BEGIN); 246 return 0; 247 248 failed: 249 ti = current->journal_info; 250 current->journal_info = ti->ti_save; 251 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 252 kmem_cache_free(nilfs_transaction_cachep, ti); 253 sb_end_intwrite(sb); 254 return ret; 255 } 256 257 /** 258 * nilfs_transaction_commit - commit indivisible file operations. 259 * @sb: super block 260 * 261 * nilfs_transaction_commit() releases the read semaphore which is 262 * acquired by nilfs_transaction_begin(). This is only performed 263 * in outermost call of this function. If a commit flag is set, 264 * nilfs_transaction_commit() sets a timer to start the segment 265 * constructor. If a sync flag is set, it starts construction 266 * directly. 267 */ 268 int nilfs_transaction_commit(struct super_block *sb) 269 { 270 struct nilfs_transaction_info *ti = current->journal_info; 271 struct the_nilfs *nilfs = sb->s_fs_info; 272 int err = 0; 273 274 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 275 ti->ti_flags |= NILFS_TI_COMMIT; 276 if (ti->ti_count > 0) { 277 ti->ti_count--; 278 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 279 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT); 280 return 0; 281 } 282 if (nilfs->ns_writer) { 283 struct nilfs_sc_info *sci = nilfs->ns_writer; 284 285 if (ti->ti_flags & NILFS_TI_COMMIT) 286 nilfs_segctor_start_timer(sci); 287 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark) 288 nilfs_segctor_do_flush(sci, 0); 289 } 290 up_read(&nilfs->ns_segctor_sem); 291 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 292 ti->ti_flags, TRACE_NILFS2_TRANSACTION_COMMIT); 293 294 current->journal_info = ti->ti_save; 295 296 if (ti->ti_flags & NILFS_TI_SYNC) 297 err = nilfs_construct_segment(sb); 298 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 299 kmem_cache_free(nilfs_transaction_cachep, ti); 300 sb_end_intwrite(sb); 301 return err; 302 } 303 304 void nilfs_transaction_abort(struct super_block *sb) 305 { 306 struct nilfs_transaction_info *ti = current->journal_info; 307 struct the_nilfs *nilfs = sb->s_fs_info; 308 309 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 310 if (ti->ti_count > 0) { 311 ti->ti_count--; 312 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 313 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT); 314 return; 315 } 316 up_read(&nilfs->ns_segctor_sem); 317 318 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 319 ti->ti_flags, TRACE_NILFS2_TRANSACTION_ABORT); 320 321 current->journal_info = ti->ti_save; 322 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 323 kmem_cache_free(nilfs_transaction_cachep, ti); 324 sb_end_intwrite(sb); 325 } 326 327 void nilfs_relax_pressure_in_lock(struct super_block *sb) 328 { 329 struct the_nilfs *nilfs = sb->s_fs_info; 330 struct nilfs_sc_info *sci = nilfs->ns_writer; 331 332 if (!sci || !sci->sc_flush_request) 333 return; 334 335 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 336 up_read(&nilfs->ns_segctor_sem); 337 338 down_write(&nilfs->ns_segctor_sem); 339 if (sci->sc_flush_request && 340 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { 341 struct nilfs_transaction_info *ti = current->journal_info; 342 343 ti->ti_flags |= NILFS_TI_WRITER; 344 nilfs_segctor_do_immediate_flush(sci); 345 ti->ti_flags &= ~NILFS_TI_WRITER; 346 } 347 downgrade_write(&nilfs->ns_segctor_sem); 348 } 349 350 static void nilfs_transaction_lock(struct super_block *sb, 351 struct nilfs_transaction_info *ti, 352 int gcflag) 353 { 354 struct nilfs_transaction_info *cur_ti = current->journal_info; 355 struct the_nilfs *nilfs = sb->s_fs_info; 356 struct nilfs_sc_info *sci = nilfs->ns_writer; 357 358 WARN_ON(cur_ti); 359 ti->ti_flags = NILFS_TI_WRITER; 360 ti->ti_count = 0; 361 ti->ti_save = cur_ti; 362 ti->ti_magic = NILFS_TI_MAGIC; 363 current->journal_info = ti; 364 365 for (;;) { 366 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 367 ti->ti_flags, TRACE_NILFS2_TRANSACTION_TRYLOCK); 368 369 down_write(&nilfs->ns_segctor_sem); 370 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) 371 break; 372 373 nilfs_segctor_do_immediate_flush(sci); 374 375 up_write(&nilfs->ns_segctor_sem); 376 yield(); 377 } 378 if (gcflag) 379 ti->ti_flags |= NILFS_TI_GC; 380 381 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 382 ti->ti_flags, TRACE_NILFS2_TRANSACTION_LOCK); 383 } 384 385 static void nilfs_transaction_unlock(struct super_block *sb) 386 { 387 struct nilfs_transaction_info *ti = current->journal_info; 388 struct the_nilfs *nilfs = sb->s_fs_info; 389 390 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 391 BUG_ON(ti->ti_count > 0); 392 393 up_write(&nilfs->ns_segctor_sem); 394 current->journal_info = ti->ti_save; 395 396 trace_nilfs2_transaction_transition(sb, ti, ti->ti_count, 397 ti->ti_flags, TRACE_NILFS2_TRANSACTION_UNLOCK); 398 } 399 400 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, 401 struct nilfs_segsum_pointer *ssp, 402 unsigned int bytes) 403 { 404 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 405 unsigned int blocksize = sci->sc_super->s_blocksize; 406 void *p; 407 408 if (unlikely(ssp->offset + bytes > blocksize)) { 409 ssp->offset = 0; 410 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, 411 &segbuf->sb_segsum_buffers)); 412 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); 413 } 414 p = ssp->bh->b_data + ssp->offset; 415 ssp->offset += bytes; 416 return p; 417 } 418 419 /** 420 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer 421 * @sci: nilfs_sc_info 422 */ 423 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) 424 { 425 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 426 struct buffer_head *sumbh; 427 unsigned int sumbytes; 428 unsigned int flags = 0; 429 int err; 430 431 if (nilfs_doing_gc()) 432 flags = NILFS_SS_GC; 433 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno); 434 if (unlikely(err)) 435 return err; 436 437 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 438 sumbytes = segbuf->sb_sum.sumbytes; 439 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; 440 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; 441 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 442 return 0; 443 } 444 445 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) 446 { 447 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 448 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) 449 return -E2BIG; /* 450 * The current segment is filled up 451 * (internal code) 452 */ 453 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); 454 return nilfs_segctor_reset_segment_buffer(sci); 455 } 456 457 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) 458 { 459 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 460 int err; 461 462 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { 463 err = nilfs_segctor_feed_segment(sci); 464 if (err) 465 return err; 466 segbuf = sci->sc_curseg; 467 } 468 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root); 469 if (likely(!err)) 470 segbuf->sb_sum.flags |= NILFS_SS_SR; 471 return err; 472 } 473 474 /* 475 * Functions for making segment summary and payloads 476 */ 477 static int nilfs_segctor_segsum_block_required( 478 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, 479 unsigned int binfo_size) 480 { 481 unsigned int blocksize = sci->sc_super->s_blocksize; 482 /* Size of finfo and binfo is enough small against blocksize */ 483 484 return ssp->offset + binfo_size + 485 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > 486 blocksize; 487 } 488 489 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, 490 struct inode *inode) 491 { 492 sci->sc_curseg->sb_sum.nfinfo++; 493 sci->sc_binfo_ptr = sci->sc_finfo_ptr; 494 nilfs_segctor_map_segsum_entry( 495 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); 496 497 if (NILFS_I(inode)->i_root && 498 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 499 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 500 /* skip finfo */ 501 } 502 503 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, 504 struct inode *inode) 505 { 506 struct nilfs_finfo *finfo; 507 struct nilfs_inode_info *ii; 508 struct nilfs_segment_buffer *segbuf; 509 __u64 cno; 510 511 if (sci->sc_blk_cnt == 0) 512 return; 513 514 ii = NILFS_I(inode); 515 516 if (test_bit(NILFS_I_GCINODE, &ii->i_state)) 517 cno = ii->i_cno; 518 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) 519 cno = 0; 520 else 521 cno = sci->sc_cno; 522 523 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, 524 sizeof(*finfo)); 525 finfo->fi_ino = cpu_to_le64(inode->i_ino); 526 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); 527 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); 528 finfo->fi_cno = cpu_to_le64(cno); 529 530 segbuf = sci->sc_curseg; 531 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + 532 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); 533 sci->sc_finfo_ptr = sci->sc_binfo_ptr; 534 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 535 } 536 537 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, 538 struct buffer_head *bh, 539 struct inode *inode, 540 unsigned int binfo_size) 541 { 542 struct nilfs_segment_buffer *segbuf; 543 int required, err = 0; 544 545 retry: 546 segbuf = sci->sc_curseg; 547 required = nilfs_segctor_segsum_block_required( 548 sci, &sci->sc_binfo_ptr, binfo_size); 549 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { 550 nilfs_segctor_end_finfo(sci, inode); 551 err = nilfs_segctor_feed_segment(sci); 552 if (err) 553 return err; 554 goto retry; 555 } 556 if (unlikely(required)) { 557 err = nilfs_segbuf_extend_segsum(segbuf); 558 if (unlikely(err)) 559 goto failed; 560 } 561 if (sci->sc_blk_cnt == 0) 562 nilfs_segctor_begin_finfo(sci, inode); 563 564 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); 565 /* Substitution to vblocknr is delayed until update_blocknr() */ 566 nilfs_segbuf_add_file_buffer(segbuf, bh); 567 sci->sc_blk_cnt++; 568 failed: 569 return err; 570 } 571 572 /* 573 * Callback functions that enumerate, mark, and collect dirty blocks 574 */ 575 static int nilfs_collect_file_data(struct nilfs_sc_info *sci, 576 struct buffer_head *bh, struct inode *inode) 577 { 578 int err; 579 580 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 581 if (err < 0) 582 return err; 583 584 err = nilfs_segctor_add_file_block(sci, bh, inode, 585 sizeof(struct nilfs_binfo_v)); 586 if (!err) 587 sci->sc_datablk_cnt++; 588 return err; 589 } 590 591 static int nilfs_collect_file_node(struct nilfs_sc_info *sci, 592 struct buffer_head *bh, 593 struct inode *inode) 594 { 595 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 596 } 597 598 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, 599 struct buffer_head *bh, 600 struct inode *inode) 601 { 602 WARN_ON(!buffer_dirty(bh)); 603 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 604 } 605 606 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, 607 struct nilfs_segsum_pointer *ssp, 608 union nilfs_binfo *binfo) 609 { 610 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( 611 sci, ssp, sizeof(*binfo_v)); 612 *binfo_v = binfo->bi_v; 613 } 614 615 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, 616 struct nilfs_segsum_pointer *ssp, 617 union nilfs_binfo *binfo) 618 { 619 __le64 *vblocknr = nilfs_segctor_map_segsum_entry( 620 sci, ssp, sizeof(*vblocknr)); 621 *vblocknr = binfo->bi_v.bi_vblocknr; 622 } 623 624 static const struct nilfs_sc_operations nilfs_sc_file_ops = { 625 .collect_data = nilfs_collect_file_data, 626 .collect_node = nilfs_collect_file_node, 627 .collect_bmap = nilfs_collect_file_bmap, 628 .write_data_binfo = nilfs_write_file_data_binfo, 629 .write_node_binfo = nilfs_write_file_node_binfo, 630 }; 631 632 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, 633 struct buffer_head *bh, struct inode *inode) 634 { 635 int err; 636 637 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 638 if (err < 0) 639 return err; 640 641 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 642 if (!err) 643 sci->sc_datablk_cnt++; 644 return err; 645 } 646 647 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, 648 struct buffer_head *bh, struct inode *inode) 649 { 650 WARN_ON(!buffer_dirty(bh)); 651 return nilfs_segctor_add_file_block(sci, bh, inode, 652 sizeof(struct nilfs_binfo_dat)); 653 } 654 655 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, 656 struct nilfs_segsum_pointer *ssp, 657 union nilfs_binfo *binfo) 658 { 659 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, 660 sizeof(*blkoff)); 661 *blkoff = binfo->bi_dat.bi_blkoff; 662 } 663 664 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, 665 struct nilfs_segsum_pointer *ssp, 666 union nilfs_binfo *binfo) 667 { 668 struct nilfs_binfo_dat *binfo_dat = 669 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); 670 *binfo_dat = binfo->bi_dat; 671 } 672 673 static const struct nilfs_sc_operations nilfs_sc_dat_ops = { 674 .collect_data = nilfs_collect_dat_data, 675 .collect_node = nilfs_collect_file_node, 676 .collect_bmap = nilfs_collect_dat_bmap, 677 .write_data_binfo = nilfs_write_dat_data_binfo, 678 .write_node_binfo = nilfs_write_dat_node_binfo, 679 }; 680 681 static const struct nilfs_sc_operations nilfs_sc_dsync_ops = { 682 .collect_data = nilfs_collect_file_data, 683 .collect_node = NULL, 684 .collect_bmap = NULL, 685 .write_data_binfo = nilfs_write_file_data_binfo, 686 .write_node_binfo = NULL, 687 }; 688 689 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, 690 struct list_head *listp, 691 size_t nlimit, 692 loff_t start, loff_t end) 693 { 694 struct address_space *mapping = inode->i_mapping; 695 struct pagevec pvec; 696 pgoff_t index = 0, last = ULONG_MAX; 697 size_t ndirties = 0; 698 int i; 699 700 if (unlikely(start != 0 || end != LLONG_MAX)) { 701 /* 702 * A valid range is given for sync-ing data pages. The 703 * range is rounded to per-page; extra dirty buffers 704 * may be included if blocksize < pagesize. 705 */ 706 index = start >> PAGE_SHIFT; 707 last = end >> PAGE_SHIFT; 708 } 709 pagevec_init(&pvec, 0); 710 repeat: 711 if (unlikely(index > last) || 712 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 713 min_t(pgoff_t, last - index, 714 PAGEVEC_SIZE - 1) + 1)) 715 return ndirties; 716 717 for (i = 0; i < pagevec_count(&pvec); i++) { 718 struct buffer_head *bh, *head; 719 struct page *page = pvec.pages[i]; 720 721 if (unlikely(page->index > last)) 722 break; 723 724 lock_page(page); 725 if (!page_has_buffers(page)) 726 create_empty_buffers(page, 1 << inode->i_blkbits, 0); 727 unlock_page(page); 728 729 bh = head = page_buffers(page); 730 do { 731 if (!buffer_dirty(bh) || buffer_async_write(bh)) 732 continue; 733 get_bh(bh); 734 list_add_tail(&bh->b_assoc_buffers, listp); 735 ndirties++; 736 if (unlikely(ndirties >= nlimit)) { 737 pagevec_release(&pvec); 738 cond_resched(); 739 return ndirties; 740 } 741 } while (bh = bh->b_this_page, bh != head); 742 } 743 pagevec_release(&pvec); 744 cond_resched(); 745 goto repeat; 746 } 747 748 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 749 struct list_head *listp) 750 { 751 struct nilfs_inode_info *ii = NILFS_I(inode); 752 struct address_space *mapping = &ii->i_btnode_cache; 753 struct pagevec pvec; 754 struct buffer_head *bh, *head; 755 unsigned int i; 756 pgoff_t index = 0; 757 758 pagevec_init(&pvec, 0); 759 760 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 761 PAGEVEC_SIZE)) { 762 for (i = 0; i < pagevec_count(&pvec); i++) { 763 bh = head = page_buffers(pvec.pages[i]); 764 do { 765 if (buffer_dirty(bh) && 766 !buffer_async_write(bh)) { 767 get_bh(bh); 768 list_add_tail(&bh->b_assoc_buffers, 769 listp); 770 } 771 bh = bh->b_this_page; 772 } while (bh != head); 773 } 774 pagevec_release(&pvec); 775 cond_resched(); 776 } 777 } 778 779 static void nilfs_dispose_list(struct the_nilfs *nilfs, 780 struct list_head *head, int force) 781 { 782 struct nilfs_inode_info *ii, *n; 783 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 784 unsigned int nv = 0; 785 786 while (!list_empty(head)) { 787 spin_lock(&nilfs->ns_inode_lock); 788 list_for_each_entry_safe(ii, n, head, i_dirty) { 789 list_del_init(&ii->i_dirty); 790 if (force) { 791 if (unlikely(ii->i_bh)) { 792 brelse(ii->i_bh); 793 ii->i_bh = NULL; 794 } 795 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 796 set_bit(NILFS_I_QUEUED, &ii->i_state); 797 list_add_tail(&ii->i_dirty, 798 &nilfs->ns_dirty_files); 799 continue; 800 } 801 ivec[nv++] = ii; 802 if (nv == SC_N_INODEVEC) 803 break; 804 } 805 spin_unlock(&nilfs->ns_inode_lock); 806 807 for (pii = ivec; nv > 0; pii++, nv--) 808 iput(&(*pii)->vfs_inode); 809 } 810 } 811 812 static void nilfs_iput_work_func(struct work_struct *work) 813 { 814 struct nilfs_sc_info *sci = container_of(work, struct nilfs_sc_info, 815 sc_iput_work); 816 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 817 818 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 0); 819 } 820 821 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs, 822 struct nilfs_root *root) 823 { 824 int ret = 0; 825 826 if (nilfs_mdt_fetch_dirty(root->ifile)) 827 ret++; 828 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 829 ret++; 830 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 831 ret++; 832 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat)) 833 ret++; 834 return ret; 835 } 836 837 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 838 { 839 return list_empty(&sci->sc_dirty_files) && 840 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 841 sci->sc_nfreesegs == 0 && 842 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 843 } 844 845 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 846 { 847 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 848 int ret = 0; 849 850 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 851 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 852 853 spin_lock(&nilfs->ns_inode_lock); 854 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci)) 855 ret++; 856 857 spin_unlock(&nilfs->ns_inode_lock); 858 return ret; 859 } 860 861 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 862 { 863 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 864 865 nilfs_mdt_clear_dirty(sci->sc_root->ifile); 866 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 867 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 868 nilfs_mdt_clear_dirty(nilfs->ns_dat); 869 } 870 871 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 872 { 873 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 874 struct buffer_head *bh_cp; 875 struct nilfs_checkpoint *raw_cp; 876 int err; 877 878 /* XXX: this interface will be changed */ 879 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 880 &raw_cp, &bh_cp); 881 if (likely(!err)) { 882 /* 883 * The following code is duplicated with cpfile. But, it is 884 * needed to collect the checkpoint even if it was not newly 885 * created. 886 */ 887 mark_buffer_dirty(bh_cp); 888 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 889 nilfs_cpfile_put_checkpoint( 890 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 891 } else 892 WARN_ON(err == -EINVAL || err == -ENOENT); 893 894 return err; 895 } 896 897 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 898 { 899 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 900 struct buffer_head *bh_cp; 901 struct nilfs_checkpoint *raw_cp; 902 int err; 903 904 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 905 &raw_cp, &bh_cp); 906 if (unlikely(err)) { 907 WARN_ON(err == -EINVAL || err == -ENOENT); 908 goto failed_ibh; 909 } 910 raw_cp->cp_snapshot_list.ssl_next = 0; 911 raw_cp->cp_snapshot_list.ssl_prev = 0; 912 raw_cp->cp_inodes_count = 913 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count)); 914 raw_cp->cp_blocks_count = 915 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count)); 916 raw_cp->cp_nblk_inc = 917 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 918 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 919 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 920 921 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 922 nilfs_checkpoint_clear_minor(raw_cp); 923 else 924 nilfs_checkpoint_set_minor(raw_cp); 925 926 nilfs_write_inode_common(sci->sc_root->ifile, 927 &raw_cp->cp_ifile_inode, 1); 928 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 929 return 0; 930 931 failed_ibh: 932 return err; 933 } 934 935 static void nilfs_fill_in_file_bmap(struct inode *ifile, 936 struct nilfs_inode_info *ii) 937 938 { 939 struct buffer_head *ibh; 940 struct nilfs_inode *raw_inode; 941 942 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 943 ibh = ii->i_bh; 944 BUG_ON(!ibh); 945 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 946 ibh); 947 nilfs_bmap_write(ii->i_bmap, raw_inode); 948 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 949 } 950 } 951 952 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci) 953 { 954 struct nilfs_inode_info *ii; 955 956 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 957 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii); 958 set_bit(NILFS_I_COLLECTED, &ii->i_state); 959 } 960 } 961 962 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 963 struct the_nilfs *nilfs) 964 { 965 struct buffer_head *bh_sr; 966 struct nilfs_super_root *raw_sr; 967 unsigned int isz, srsz; 968 969 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root; 970 raw_sr = (struct nilfs_super_root *)bh_sr->b_data; 971 isz = nilfs->ns_inode_size; 972 srsz = NILFS_SR_BYTES(isz); 973 974 raw_sr->sr_bytes = cpu_to_le16(srsz); 975 raw_sr->sr_nongc_ctime 976 = cpu_to_le64(nilfs_doing_gc() ? 977 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 978 raw_sr->sr_flags = 0; 979 980 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr + 981 NILFS_SR_DAT_OFFSET(isz), 1); 982 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr + 983 NILFS_SR_CPFILE_OFFSET(isz), 1); 984 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr + 985 NILFS_SR_SUFILE_OFFSET(isz), 1); 986 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz); 987 } 988 989 static void nilfs_redirty_inodes(struct list_head *head) 990 { 991 struct nilfs_inode_info *ii; 992 993 list_for_each_entry(ii, head, i_dirty) { 994 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 995 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 996 } 997 } 998 999 static void nilfs_drop_collected_inodes(struct list_head *head) 1000 { 1001 struct nilfs_inode_info *ii; 1002 1003 list_for_each_entry(ii, head, i_dirty) { 1004 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 1005 continue; 1006 1007 clear_bit(NILFS_I_INODE_SYNC, &ii->i_state); 1008 set_bit(NILFS_I_UPDATED, &ii->i_state); 1009 } 1010 } 1011 1012 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 1013 struct inode *inode, 1014 struct list_head *listp, 1015 int (*collect)(struct nilfs_sc_info *, 1016 struct buffer_head *, 1017 struct inode *)) 1018 { 1019 struct buffer_head *bh, *n; 1020 int err = 0; 1021 1022 if (collect) { 1023 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 1024 list_del_init(&bh->b_assoc_buffers); 1025 err = collect(sci, bh, inode); 1026 brelse(bh); 1027 if (unlikely(err)) 1028 goto dispose_buffers; 1029 } 1030 return 0; 1031 } 1032 1033 dispose_buffers: 1034 while (!list_empty(listp)) { 1035 bh = list_first_entry(listp, struct buffer_head, 1036 b_assoc_buffers); 1037 list_del_init(&bh->b_assoc_buffers); 1038 brelse(bh); 1039 } 1040 return err; 1041 } 1042 1043 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 1044 { 1045 /* Remaining number of blocks within segment buffer */ 1046 return sci->sc_segbuf_nblocks - 1047 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 1048 } 1049 1050 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 1051 struct inode *inode, 1052 const struct nilfs_sc_operations *sc_ops) 1053 { 1054 LIST_HEAD(data_buffers); 1055 LIST_HEAD(node_buffers); 1056 int err; 1057 1058 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1059 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1060 1061 n = nilfs_lookup_dirty_data_buffers( 1062 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 1063 if (n > rest) { 1064 err = nilfs_segctor_apply_buffers( 1065 sci, inode, &data_buffers, 1066 sc_ops->collect_data); 1067 BUG_ON(!err); /* always receive -E2BIG or true error */ 1068 goto break_or_fail; 1069 } 1070 } 1071 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 1072 1073 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 1074 err = nilfs_segctor_apply_buffers( 1075 sci, inode, &data_buffers, sc_ops->collect_data); 1076 if (unlikely(err)) { 1077 /* dispose node list */ 1078 nilfs_segctor_apply_buffers( 1079 sci, inode, &node_buffers, NULL); 1080 goto break_or_fail; 1081 } 1082 sci->sc_stage.flags |= NILFS_CF_NODE; 1083 } 1084 /* Collect node */ 1085 err = nilfs_segctor_apply_buffers( 1086 sci, inode, &node_buffers, sc_ops->collect_node); 1087 if (unlikely(err)) 1088 goto break_or_fail; 1089 1090 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1091 err = nilfs_segctor_apply_buffers( 1092 sci, inode, &node_buffers, sc_ops->collect_bmap); 1093 if (unlikely(err)) 1094 goto break_or_fail; 1095 1096 nilfs_segctor_end_finfo(sci, inode); 1097 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1098 1099 break_or_fail: 1100 return err; 1101 } 1102 1103 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1104 struct inode *inode) 1105 { 1106 LIST_HEAD(data_buffers); 1107 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1108 int err; 1109 1110 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1111 sci->sc_dsync_start, 1112 sci->sc_dsync_end); 1113 1114 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1115 nilfs_collect_file_data); 1116 if (!err) { 1117 nilfs_segctor_end_finfo(sci, inode); 1118 BUG_ON(n > rest); 1119 /* always receive -E2BIG or true error if n > rest */ 1120 } 1121 return err; 1122 } 1123 1124 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1125 { 1126 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1127 struct list_head *head; 1128 struct nilfs_inode_info *ii; 1129 size_t ndone; 1130 int err = 0; 1131 1132 switch (nilfs_sc_cstage_get(sci)) { 1133 case NILFS_ST_INIT: 1134 /* Pre-processes */ 1135 sci->sc_stage.flags = 0; 1136 1137 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1138 sci->sc_nblk_inc = 0; 1139 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1140 if (mode == SC_LSEG_DSYNC) { 1141 nilfs_sc_cstage_set(sci, NILFS_ST_DSYNC); 1142 goto dsync_mode; 1143 } 1144 } 1145 1146 sci->sc_stage.dirty_file_ptr = NULL; 1147 sci->sc_stage.gc_inode_ptr = NULL; 1148 if (mode == SC_FLUSH_DAT) { 1149 nilfs_sc_cstage_set(sci, NILFS_ST_DAT); 1150 goto dat_stage; 1151 } 1152 nilfs_sc_cstage_inc(sci); /* Fall through */ 1153 case NILFS_ST_GC: 1154 if (nilfs_doing_gc()) { 1155 head = &sci->sc_gc_inodes; 1156 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1157 head, i_dirty); 1158 list_for_each_entry_continue(ii, head, i_dirty) { 1159 err = nilfs_segctor_scan_file( 1160 sci, &ii->vfs_inode, 1161 &nilfs_sc_file_ops); 1162 if (unlikely(err)) { 1163 sci->sc_stage.gc_inode_ptr = list_entry( 1164 ii->i_dirty.prev, 1165 struct nilfs_inode_info, 1166 i_dirty); 1167 goto break_or_fail; 1168 } 1169 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1170 } 1171 sci->sc_stage.gc_inode_ptr = NULL; 1172 } 1173 nilfs_sc_cstage_inc(sci); /* Fall through */ 1174 case NILFS_ST_FILE: 1175 head = &sci->sc_dirty_files; 1176 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1177 i_dirty); 1178 list_for_each_entry_continue(ii, head, i_dirty) { 1179 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1180 1181 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1182 &nilfs_sc_file_ops); 1183 if (unlikely(err)) { 1184 sci->sc_stage.dirty_file_ptr = 1185 list_entry(ii->i_dirty.prev, 1186 struct nilfs_inode_info, 1187 i_dirty); 1188 goto break_or_fail; 1189 } 1190 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1191 /* XXX: required ? */ 1192 } 1193 sci->sc_stage.dirty_file_ptr = NULL; 1194 if (mode == SC_FLUSH_FILE) { 1195 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1196 return 0; 1197 } 1198 nilfs_sc_cstage_inc(sci); 1199 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1200 /* Fall through */ 1201 case NILFS_ST_IFILE: 1202 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile, 1203 &nilfs_sc_file_ops); 1204 if (unlikely(err)) 1205 break; 1206 nilfs_sc_cstage_inc(sci); 1207 /* Creating a checkpoint */ 1208 err = nilfs_segctor_create_checkpoint(sci); 1209 if (unlikely(err)) 1210 break; 1211 /* Fall through */ 1212 case NILFS_ST_CPFILE: 1213 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1214 &nilfs_sc_file_ops); 1215 if (unlikely(err)) 1216 break; 1217 nilfs_sc_cstage_inc(sci); /* Fall through */ 1218 case NILFS_ST_SUFILE: 1219 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1220 sci->sc_nfreesegs, &ndone); 1221 if (unlikely(err)) { 1222 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1223 sci->sc_freesegs, ndone, 1224 NULL); 1225 break; 1226 } 1227 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1228 1229 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1230 &nilfs_sc_file_ops); 1231 if (unlikely(err)) 1232 break; 1233 nilfs_sc_cstage_inc(sci); /* Fall through */ 1234 case NILFS_ST_DAT: 1235 dat_stage: 1236 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat, 1237 &nilfs_sc_dat_ops); 1238 if (unlikely(err)) 1239 break; 1240 if (mode == SC_FLUSH_DAT) { 1241 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1242 return 0; 1243 } 1244 nilfs_sc_cstage_inc(sci); /* Fall through */ 1245 case NILFS_ST_SR: 1246 if (mode == SC_LSEG_SR) { 1247 /* Appending a super root */ 1248 err = nilfs_segctor_add_super_root(sci); 1249 if (unlikely(err)) 1250 break; 1251 } 1252 /* End of a logical segment */ 1253 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1254 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1255 return 0; 1256 case NILFS_ST_DSYNC: 1257 dsync_mode: 1258 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1259 ii = sci->sc_dsync_inode; 1260 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1261 break; 1262 1263 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1264 if (unlikely(err)) 1265 break; 1266 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1267 nilfs_sc_cstage_set(sci, NILFS_ST_DONE); 1268 return 0; 1269 case NILFS_ST_DONE: 1270 return 0; 1271 default: 1272 BUG(); 1273 } 1274 1275 break_or_fail: 1276 return err; 1277 } 1278 1279 /** 1280 * nilfs_segctor_begin_construction - setup segment buffer to make a new log 1281 * @sci: nilfs_sc_info 1282 * @nilfs: nilfs object 1283 */ 1284 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1285 struct the_nilfs *nilfs) 1286 { 1287 struct nilfs_segment_buffer *segbuf, *prev; 1288 __u64 nextnum; 1289 int err, alloc = 0; 1290 1291 segbuf = nilfs_segbuf_new(sci->sc_super); 1292 if (unlikely(!segbuf)) 1293 return -ENOMEM; 1294 1295 if (list_empty(&sci->sc_write_logs)) { 1296 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 1297 nilfs->ns_pseg_offset, nilfs); 1298 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1299 nilfs_shift_to_next_segment(nilfs); 1300 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1301 } 1302 1303 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1304 nextnum = nilfs->ns_nextnum; 1305 1306 if (nilfs->ns_segnum == nilfs->ns_nextnum) 1307 /* Start from the head of a new full segment */ 1308 alloc++; 1309 } else { 1310 /* Continue logs */ 1311 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1312 nilfs_segbuf_map_cont(segbuf, prev); 1313 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq; 1314 nextnum = prev->sb_nextnum; 1315 1316 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1317 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1318 segbuf->sb_sum.seg_seq++; 1319 alloc++; 1320 } 1321 } 1322 1323 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum); 1324 if (err) 1325 goto failed; 1326 1327 if (alloc) { 1328 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1329 if (err) 1330 goto failed; 1331 } 1332 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1333 1334 BUG_ON(!list_empty(&sci->sc_segbufs)); 1335 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs); 1336 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1337 return 0; 1338 1339 failed: 1340 nilfs_segbuf_free(segbuf); 1341 return err; 1342 } 1343 1344 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1345 struct the_nilfs *nilfs, int nadd) 1346 { 1347 struct nilfs_segment_buffer *segbuf, *prev; 1348 struct inode *sufile = nilfs->ns_sufile; 1349 __u64 nextnextnum; 1350 LIST_HEAD(list); 1351 int err, ret, i; 1352 1353 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1354 /* 1355 * Since the segment specified with nextnum might be allocated during 1356 * the previous construction, the buffer including its segusage may 1357 * not be dirty. The following call ensures that the buffer is dirty 1358 * and will pin the buffer on memory until the sufile is written. 1359 */ 1360 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum); 1361 if (unlikely(err)) 1362 return err; 1363 1364 for (i = 0; i < nadd; i++) { 1365 /* extend segment info */ 1366 err = -ENOMEM; 1367 segbuf = nilfs_segbuf_new(sci->sc_super); 1368 if (unlikely(!segbuf)) 1369 goto failed; 1370 1371 /* map this buffer to region of segment on-disk */ 1372 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1373 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1374 1375 /* allocate the next next full segment */ 1376 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1377 if (unlikely(err)) 1378 goto failed_segbuf; 1379 1380 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1381 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1382 1383 list_add_tail(&segbuf->sb_list, &list); 1384 prev = segbuf; 1385 } 1386 list_splice_tail(&list, &sci->sc_segbufs); 1387 return 0; 1388 1389 failed_segbuf: 1390 nilfs_segbuf_free(segbuf); 1391 failed: 1392 list_for_each_entry(segbuf, &list, sb_list) { 1393 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1394 WARN_ON(ret); /* never fails */ 1395 } 1396 nilfs_destroy_logs(&list); 1397 return err; 1398 } 1399 1400 static void nilfs_free_incomplete_logs(struct list_head *logs, 1401 struct the_nilfs *nilfs) 1402 { 1403 struct nilfs_segment_buffer *segbuf, *prev; 1404 struct inode *sufile = nilfs->ns_sufile; 1405 int ret; 1406 1407 segbuf = NILFS_FIRST_SEGBUF(logs); 1408 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1409 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1410 WARN_ON(ret); /* never fails */ 1411 } 1412 if (atomic_read(&segbuf->sb_err)) { 1413 /* Case 1: The first segment failed */ 1414 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1415 /* 1416 * Case 1a: Partial segment appended into an existing 1417 * segment 1418 */ 1419 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1420 segbuf->sb_fseg_end); 1421 else /* Case 1b: New full segment */ 1422 set_nilfs_discontinued(nilfs); 1423 } 1424 1425 prev = segbuf; 1426 list_for_each_entry_continue(segbuf, logs, sb_list) { 1427 if (prev->sb_nextnum != segbuf->sb_nextnum) { 1428 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1429 WARN_ON(ret); /* never fails */ 1430 } 1431 if (atomic_read(&segbuf->sb_err) && 1432 segbuf->sb_segnum != nilfs->ns_nextnum) 1433 /* Case 2: extended segment (!= next) failed */ 1434 nilfs_sufile_set_error(sufile, segbuf->sb_segnum); 1435 prev = segbuf; 1436 } 1437 } 1438 1439 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1440 struct inode *sufile) 1441 { 1442 struct nilfs_segment_buffer *segbuf; 1443 unsigned long live_blocks; 1444 int ret; 1445 1446 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1447 live_blocks = segbuf->sb_sum.nblocks + 1448 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1449 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1450 live_blocks, 1451 sci->sc_seg_ctime); 1452 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1453 } 1454 } 1455 1456 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile) 1457 { 1458 struct nilfs_segment_buffer *segbuf; 1459 int ret; 1460 1461 segbuf = NILFS_FIRST_SEGBUF(logs); 1462 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1463 segbuf->sb_pseg_start - 1464 segbuf->sb_fseg_start, 0); 1465 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1466 1467 list_for_each_entry_continue(segbuf, logs, sb_list) { 1468 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1469 0, 0); 1470 WARN_ON(ret); /* always succeed */ 1471 } 1472 } 1473 1474 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1475 struct nilfs_segment_buffer *last, 1476 struct inode *sufile) 1477 { 1478 struct nilfs_segment_buffer *segbuf = last; 1479 int ret; 1480 1481 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1482 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1483 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1484 WARN_ON(ret); 1485 } 1486 nilfs_truncate_logs(&sci->sc_segbufs, last); 1487 } 1488 1489 1490 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1491 struct the_nilfs *nilfs, int mode) 1492 { 1493 struct nilfs_cstage prev_stage = sci->sc_stage; 1494 int err, nadd = 1; 1495 1496 /* Collection retry loop */ 1497 for (;;) { 1498 sci->sc_nblk_this_inc = 0; 1499 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1500 1501 err = nilfs_segctor_reset_segment_buffer(sci); 1502 if (unlikely(err)) 1503 goto failed; 1504 1505 err = nilfs_segctor_collect_blocks(sci, mode); 1506 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1507 if (!err) 1508 break; 1509 1510 if (unlikely(err != -E2BIG)) 1511 goto failed; 1512 1513 /* The current segment is filled up */ 1514 if (mode != SC_LSEG_SR || 1515 nilfs_sc_cstage_get(sci) < NILFS_ST_CPFILE) 1516 break; 1517 1518 nilfs_clear_logs(&sci->sc_segbufs); 1519 1520 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1521 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1522 sci->sc_freesegs, 1523 sci->sc_nfreesegs, 1524 NULL); 1525 WARN_ON(err); /* do not happen */ 1526 sci->sc_stage.flags &= ~NILFS_CF_SUFREED; 1527 } 1528 1529 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1530 if (unlikely(err)) 1531 return err; 1532 1533 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1534 sci->sc_stage = prev_stage; 1535 } 1536 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1537 return 0; 1538 1539 failed: 1540 return err; 1541 } 1542 1543 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1544 struct buffer_head *new_bh) 1545 { 1546 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1547 1548 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1549 /* The caller must release old_bh */ 1550 } 1551 1552 static int 1553 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1554 struct nilfs_segment_buffer *segbuf, 1555 int mode) 1556 { 1557 struct inode *inode = NULL; 1558 sector_t blocknr; 1559 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1560 unsigned long nblocks = 0, ndatablk = 0; 1561 const struct nilfs_sc_operations *sc_op = NULL; 1562 struct nilfs_segsum_pointer ssp; 1563 struct nilfs_finfo *finfo = NULL; 1564 union nilfs_binfo binfo; 1565 struct buffer_head *bh, *bh_org; 1566 ino_t ino = 0; 1567 int err = 0; 1568 1569 if (!nfinfo) 1570 goto out; 1571 1572 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1573 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1574 ssp.offset = sizeof(struct nilfs_segment_summary); 1575 1576 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1577 if (bh == segbuf->sb_super_root) 1578 break; 1579 if (!finfo) { 1580 finfo = nilfs_segctor_map_segsum_entry( 1581 sci, &ssp, sizeof(*finfo)); 1582 ino = le64_to_cpu(finfo->fi_ino); 1583 nblocks = le32_to_cpu(finfo->fi_nblocks); 1584 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1585 1586 inode = bh->b_page->mapping->host; 1587 1588 if (mode == SC_LSEG_DSYNC) 1589 sc_op = &nilfs_sc_dsync_ops; 1590 else if (ino == NILFS_DAT_INO) 1591 sc_op = &nilfs_sc_dat_ops; 1592 else /* file blocks */ 1593 sc_op = &nilfs_sc_file_ops; 1594 } 1595 bh_org = bh; 1596 get_bh(bh_org); 1597 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1598 &binfo); 1599 if (bh != bh_org) 1600 nilfs_list_replace_buffer(bh_org, bh); 1601 brelse(bh_org); 1602 if (unlikely(err)) 1603 goto failed_bmap; 1604 1605 if (ndatablk > 0) 1606 sc_op->write_data_binfo(sci, &ssp, &binfo); 1607 else 1608 sc_op->write_node_binfo(sci, &ssp, &binfo); 1609 1610 blocknr++; 1611 if (--nblocks == 0) { 1612 finfo = NULL; 1613 if (--nfinfo == 0) 1614 break; 1615 } else if (ndatablk > 0) 1616 ndatablk--; 1617 } 1618 out: 1619 return 0; 1620 1621 failed_bmap: 1622 return err; 1623 } 1624 1625 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1626 { 1627 struct nilfs_segment_buffer *segbuf; 1628 int err; 1629 1630 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1631 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1632 if (unlikely(err)) 1633 return err; 1634 nilfs_segbuf_fill_in_segsum(segbuf); 1635 } 1636 return 0; 1637 } 1638 1639 static void nilfs_begin_page_io(struct page *page) 1640 { 1641 if (!page || PageWriteback(page)) 1642 /* 1643 * For split b-tree node pages, this function may be called 1644 * twice. We ignore the 2nd or later calls by this check. 1645 */ 1646 return; 1647 1648 lock_page(page); 1649 clear_page_dirty_for_io(page); 1650 set_page_writeback(page); 1651 unlock_page(page); 1652 } 1653 1654 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci) 1655 { 1656 struct nilfs_segment_buffer *segbuf; 1657 struct page *bd_page = NULL, *fs_page = NULL; 1658 1659 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1660 struct buffer_head *bh; 1661 1662 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1663 b_assoc_buffers) { 1664 if (bh->b_page != bd_page) { 1665 if (bd_page) { 1666 lock_page(bd_page); 1667 clear_page_dirty_for_io(bd_page); 1668 set_page_writeback(bd_page); 1669 unlock_page(bd_page); 1670 } 1671 bd_page = bh->b_page; 1672 } 1673 } 1674 1675 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1676 b_assoc_buffers) { 1677 set_buffer_async_write(bh); 1678 if (bh == segbuf->sb_super_root) { 1679 if (bh->b_page != bd_page) { 1680 lock_page(bd_page); 1681 clear_page_dirty_for_io(bd_page); 1682 set_page_writeback(bd_page); 1683 unlock_page(bd_page); 1684 bd_page = bh->b_page; 1685 } 1686 break; 1687 } 1688 if (bh->b_page != fs_page) { 1689 nilfs_begin_page_io(fs_page); 1690 fs_page = bh->b_page; 1691 } 1692 } 1693 } 1694 if (bd_page) { 1695 lock_page(bd_page); 1696 clear_page_dirty_for_io(bd_page); 1697 set_page_writeback(bd_page); 1698 unlock_page(bd_page); 1699 } 1700 nilfs_begin_page_io(fs_page); 1701 } 1702 1703 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1704 struct the_nilfs *nilfs) 1705 { 1706 int ret; 1707 1708 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs); 1709 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs); 1710 return ret; 1711 } 1712 1713 static void nilfs_end_page_io(struct page *page, int err) 1714 { 1715 if (!page) 1716 return; 1717 1718 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) { 1719 /* 1720 * For b-tree node pages, this function may be called twice 1721 * or more because they might be split in a segment. 1722 */ 1723 if (PageDirty(page)) { 1724 /* 1725 * For pages holding split b-tree node buffers, dirty 1726 * flag on the buffers may be cleared discretely. 1727 * In that case, the page is once redirtied for 1728 * remaining buffers, and it must be cancelled if 1729 * all the buffers get cleaned later. 1730 */ 1731 lock_page(page); 1732 if (nilfs_page_buffers_clean(page)) 1733 __nilfs_clear_page_dirty(page); 1734 unlock_page(page); 1735 } 1736 return; 1737 } 1738 1739 if (!err) { 1740 if (!nilfs_page_buffers_clean(page)) 1741 __set_page_dirty_nobuffers(page); 1742 ClearPageError(page); 1743 } else { 1744 __set_page_dirty_nobuffers(page); 1745 SetPageError(page); 1746 } 1747 1748 end_page_writeback(page); 1749 } 1750 1751 static void nilfs_abort_logs(struct list_head *logs, int err) 1752 { 1753 struct nilfs_segment_buffer *segbuf; 1754 struct page *bd_page = NULL, *fs_page = NULL; 1755 struct buffer_head *bh; 1756 1757 if (list_empty(logs)) 1758 return; 1759 1760 list_for_each_entry(segbuf, logs, sb_list) { 1761 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1762 b_assoc_buffers) { 1763 if (bh->b_page != bd_page) { 1764 if (bd_page) 1765 end_page_writeback(bd_page); 1766 bd_page = bh->b_page; 1767 } 1768 } 1769 1770 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1771 b_assoc_buffers) { 1772 clear_buffer_async_write(bh); 1773 if (bh == segbuf->sb_super_root) { 1774 if (bh->b_page != bd_page) { 1775 end_page_writeback(bd_page); 1776 bd_page = bh->b_page; 1777 } 1778 break; 1779 } 1780 if (bh->b_page != fs_page) { 1781 nilfs_end_page_io(fs_page, err); 1782 fs_page = bh->b_page; 1783 } 1784 } 1785 } 1786 if (bd_page) 1787 end_page_writeback(bd_page); 1788 1789 nilfs_end_page_io(fs_page, err); 1790 } 1791 1792 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci, 1793 struct the_nilfs *nilfs, int err) 1794 { 1795 LIST_HEAD(logs); 1796 int ret; 1797 1798 list_splice_tail_init(&sci->sc_write_logs, &logs); 1799 ret = nilfs_wait_on_logs(&logs); 1800 nilfs_abort_logs(&logs, ret ? : err); 1801 1802 list_splice_tail_init(&sci->sc_segbufs, &logs); 1803 nilfs_cancel_segusage(&logs, nilfs->ns_sufile); 1804 nilfs_free_incomplete_logs(&logs, nilfs); 1805 1806 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1807 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1808 sci->sc_freesegs, 1809 sci->sc_nfreesegs, 1810 NULL); 1811 WARN_ON(ret); /* do not happen */ 1812 } 1813 1814 nilfs_destroy_logs(&logs); 1815 } 1816 1817 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1818 struct nilfs_segment_buffer *segbuf) 1819 { 1820 nilfs->ns_segnum = segbuf->sb_segnum; 1821 nilfs->ns_nextnum = segbuf->sb_nextnum; 1822 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1823 + segbuf->sb_sum.nblocks; 1824 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1825 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1826 } 1827 1828 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1829 { 1830 struct nilfs_segment_buffer *segbuf; 1831 struct page *bd_page = NULL, *fs_page = NULL; 1832 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1833 int update_sr = false; 1834 1835 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) { 1836 struct buffer_head *bh; 1837 1838 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1839 b_assoc_buffers) { 1840 set_buffer_uptodate(bh); 1841 clear_buffer_dirty(bh); 1842 if (bh->b_page != bd_page) { 1843 if (bd_page) 1844 end_page_writeback(bd_page); 1845 bd_page = bh->b_page; 1846 } 1847 } 1848 /* 1849 * We assume that the buffers which belong to the same page 1850 * continue over the buffer list. 1851 * Under this assumption, the last BHs of pages is 1852 * identifiable by the discontinuity of bh->b_page 1853 * (page != fs_page). 1854 * 1855 * For B-tree node blocks, however, this assumption is not 1856 * guaranteed. The cleanup code of B-tree node pages needs 1857 * special care. 1858 */ 1859 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1860 b_assoc_buffers) { 1861 const unsigned long set_bits = (1 << BH_Uptodate); 1862 const unsigned long clear_bits = 1863 (1 << BH_Dirty | 1 << BH_Async_Write | 1864 1 << BH_Delay | 1 << BH_NILFS_Volatile | 1865 1 << BH_NILFS_Redirected); 1866 1867 set_mask_bits(&bh->b_state, clear_bits, set_bits); 1868 if (bh == segbuf->sb_super_root) { 1869 if (bh->b_page != bd_page) { 1870 end_page_writeback(bd_page); 1871 bd_page = bh->b_page; 1872 } 1873 update_sr = true; 1874 break; 1875 } 1876 if (bh->b_page != fs_page) { 1877 nilfs_end_page_io(fs_page, 0); 1878 fs_page = bh->b_page; 1879 } 1880 } 1881 1882 if (!nilfs_segbuf_simplex(segbuf)) { 1883 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) { 1884 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1885 sci->sc_lseg_stime = jiffies; 1886 } 1887 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND) 1888 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1889 } 1890 } 1891 /* 1892 * Since pages may continue over multiple segment buffers, 1893 * end of the last page must be checked outside of the loop. 1894 */ 1895 if (bd_page) 1896 end_page_writeback(bd_page); 1897 1898 nilfs_end_page_io(fs_page, 0); 1899 1900 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 1901 1902 if (nilfs_doing_gc()) 1903 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 1904 else 1905 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 1906 1907 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 1908 1909 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1910 nilfs_set_next_segment(nilfs, segbuf); 1911 1912 if (update_sr) { 1913 nilfs->ns_flushed_device = 0; 1914 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 1915 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 1916 1917 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 1918 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 1919 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1920 nilfs_segctor_clear_metadata_dirty(sci); 1921 } else 1922 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1923 } 1924 1925 static int nilfs_segctor_wait(struct nilfs_sc_info *sci) 1926 { 1927 int ret; 1928 1929 ret = nilfs_wait_on_logs(&sci->sc_write_logs); 1930 if (!ret) { 1931 nilfs_segctor_complete_write(sci); 1932 nilfs_destroy_logs(&sci->sc_write_logs); 1933 } 1934 return ret; 1935 } 1936 1937 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci, 1938 struct the_nilfs *nilfs) 1939 { 1940 struct nilfs_inode_info *ii, *n; 1941 struct inode *ifile = sci->sc_root->ifile; 1942 1943 spin_lock(&nilfs->ns_inode_lock); 1944 retry: 1945 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) { 1946 if (!ii->i_bh) { 1947 struct buffer_head *ibh; 1948 int err; 1949 1950 spin_unlock(&nilfs->ns_inode_lock); 1951 err = nilfs_ifile_get_inode_block( 1952 ifile, ii->vfs_inode.i_ino, &ibh); 1953 if (unlikely(err)) { 1954 nilfs_warning(sci->sc_super, __func__, 1955 "failed to get inode block."); 1956 return err; 1957 } 1958 mark_buffer_dirty(ibh); 1959 nilfs_mdt_mark_dirty(ifile); 1960 spin_lock(&nilfs->ns_inode_lock); 1961 if (likely(!ii->i_bh)) 1962 ii->i_bh = ibh; 1963 else 1964 brelse(ibh); 1965 goto retry; 1966 } 1967 1968 clear_bit(NILFS_I_QUEUED, &ii->i_state); 1969 set_bit(NILFS_I_BUSY, &ii->i_state); 1970 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files); 1971 } 1972 spin_unlock(&nilfs->ns_inode_lock); 1973 1974 return 0; 1975 } 1976 1977 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci, 1978 struct the_nilfs *nilfs) 1979 { 1980 struct nilfs_inode_info *ii, *n; 1981 int during_mount = !(sci->sc_super->s_flags & MS_ACTIVE); 1982 int defer_iput = false; 1983 1984 spin_lock(&nilfs->ns_inode_lock); 1985 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 1986 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 1987 test_bit(NILFS_I_DIRTY, &ii->i_state)) 1988 continue; 1989 1990 clear_bit(NILFS_I_BUSY, &ii->i_state); 1991 brelse(ii->i_bh); 1992 ii->i_bh = NULL; 1993 list_del_init(&ii->i_dirty); 1994 if (!ii->vfs_inode.i_nlink || during_mount) { 1995 /* 1996 * Defer calling iput() to avoid deadlocks if 1997 * i_nlink == 0 or mount is not yet finished. 1998 */ 1999 list_add_tail(&ii->i_dirty, &sci->sc_iput_queue); 2000 defer_iput = true; 2001 } else { 2002 spin_unlock(&nilfs->ns_inode_lock); 2003 iput(&ii->vfs_inode); 2004 spin_lock(&nilfs->ns_inode_lock); 2005 } 2006 } 2007 spin_unlock(&nilfs->ns_inode_lock); 2008 2009 if (defer_iput) 2010 schedule_work(&sci->sc_iput_work); 2011 } 2012 2013 /* 2014 * Main procedure of segment constructor 2015 */ 2016 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 2017 { 2018 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2019 int err; 2020 2021 nilfs_sc_cstage_set(sci, NILFS_ST_INIT); 2022 sci->sc_cno = nilfs->ns_cno; 2023 2024 err = nilfs_segctor_collect_dirty_files(sci, nilfs); 2025 if (unlikely(err)) 2026 goto out; 2027 2028 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 2029 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 2030 2031 if (nilfs_segctor_clean(sci)) 2032 goto out; 2033 2034 do { 2035 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 2036 2037 err = nilfs_segctor_begin_construction(sci, nilfs); 2038 if (unlikely(err)) 2039 goto out; 2040 2041 /* Update time stamp */ 2042 sci->sc_seg_ctime = get_seconds(); 2043 2044 err = nilfs_segctor_collect(sci, nilfs, mode); 2045 if (unlikely(err)) 2046 goto failed; 2047 2048 /* Avoid empty segment */ 2049 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE && 2050 nilfs_segbuf_empty(sci->sc_curseg)) { 2051 nilfs_segctor_abort_construction(sci, nilfs, 1); 2052 goto out; 2053 } 2054 2055 err = nilfs_segctor_assign(sci, mode); 2056 if (unlikely(err)) 2057 goto failed; 2058 2059 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2060 nilfs_segctor_fill_in_file_bmap(sci); 2061 2062 if (mode == SC_LSEG_SR && 2063 nilfs_sc_cstage_get(sci) >= NILFS_ST_CPFILE) { 2064 err = nilfs_segctor_fill_in_checkpoint(sci); 2065 if (unlikely(err)) 2066 goto failed_to_write; 2067 2068 nilfs_segctor_fill_in_super_root(sci, nilfs); 2069 } 2070 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 2071 2072 /* Write partial segments */ 2073 nilfs_segctor_prepare_write(sci); 2074 2075 nilfs_add_checksums_on_logs(&sci->sc_segbufs, 2076 nilfs->ns_crc_seed); 2077 2078 err = nilfs_segctor_write(sci, nilfs); 2079 if (unlikely(err)) 2080 goto failed_to_write; 2081 2082 if (nilfs_sc_cstage_get(sci) == NILFS_ST_DONE || 2083 nilfs->ns_blocksize_bits != PAGE_SHIFT) { 2084 /* 2085 * At this point, we avoid double buffering 2086 * for blocksize < pagesize because page dirty 2087 * flag is turned off during write and dirty 2088 * buffers are not properly collected for 2089 * pages crossing over segments. 2090 */ 2091 err = nilfs_segctor_wait(sci); 2092 if (err) 2093 goto failed_to_write; 2094 } 2095 } while (nilfs_sc_cstage_get(sci) != NILFS_ST_DONE); 2096 2097 out: 2098 nilfs_segctor_drop_written_files(sci, nilfs); 2099 return err; 2100 2101 failed_to_write: 2102 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2103 nilfs_redirty_inodes(&sci->sc_dirty_files); 2104 2105 failed: 2106 if (nilfs_doing_gc()) 2107 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2108 nilfs_segctor_abort_construction(sci, nilfs, err); 2109 goto out; 2110 } 2111 2112 /** 2113 * nilfs_segctor_start_timer - set timer of background write 2114 * @sci: nilfs_sc_info 2115 * 2116 * If the timer has already been set, it ignores the new request. 2117 * This function MUST be called within a section locking the segment 2118 * semaphore. 2119 */ 2120 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2121 { 2122 spin_lock(&sci->sc_state_lock); 2123 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2124 sci->sc_timer.expires = jiffies + sci->sc_interval; 2125 add_timer(&sci->sc_timer); 2126 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2127 } 2128 spin_unlock(&sci->sc_state_lock); 2129 } 2130 2131 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2132 { 2133 spin_lock(&sci->sc_state_lock); 2134 if (!(sci->sc_flush_request & (1 << bn))) { 2135 unsigned long prev_req = sci->sc_flush_request; 2136 2137 sci->sc_flush_request |= (1 << bn); 2138 if (!prev_req) 2139 wake_up(&sci->sc_wait_daemon); 2140 } 2141 spin_unlock(&sci->sc_state_lock); 2142 } 2143 2144 /** 2145 * nilfs_flush_segment - trigger a segment construction for resource control 2146 * @sb: super block 2147 * @ino: inode number of the file to be flushed out. 2148 */ 2149 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2150 { 2151 struct the_nilfs *nilfs = sb->s_fs_info; 2152 struct nilfs_sc_info *sci = nilfs->ns_writer; 2153 2154 if (!sci || nilfs_doing_construction()) 2155 return; 2156 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2157 /* assign bit 0 to data files */ 2158 } 2159 2160 struct nilfs_segctor_wait_request { 2161 wait_queue_t wq; 2162 __u32 seq; 2163 int err; 2164 atomic_t done; 2165 }; 2166 2167 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2168 { 2169 struct nilfs_segctor_wait_request wait_req; 2170 int err = 0; 2171 2172 spin_lock(&sci->sc_state_lock); 2173 init_wait(&wait_req.wq); 2174 wait_req.err = 0; 2175 atomic_set(&wait_req.done, 0); 2176 wait_req.seq = ++sci->sc_seq_request; 2177 spin_unlock(&sci->sc_state_lock); 2178 2179 init_waitqueue_entry(&wait_req.wq, current); 2180 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2181 set_current_state(TASK_INTERRUPTIBLE); 2182 wake_up(&sci->sc_wait_daemon); 2183 2184 for (;;) { 2185 if (atomic_read(&wait_req.done)) { 2186 err = wait_req.err; 2187 break; 2188 } 2189 if (!signal_pending(current)) { 2190 schedule(); 2191 continue; 2192 } 2193 err = -ERESTARTSYS; 2194 break; 2195 } 2196 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2197 return err; 2198 } 2199 2200 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2201 { 2202 struct nilfs_segctor_wait_request *wrq, *n; 2203 unsigned long flags; 2204 2205 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2206 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list, 2207 wq.task_list) { 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 (1 << 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(unsigned long data) 2406 { 2407 struct task_struct *p = (struct task_struct *)data; 2408 2409 wake_up_process(p); 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_warning(sb, __func__, 2462 "segment construction failed. (err=%d)", err); 2463 set_current_state(TASK_INTERRUPTIBLE); 2464 schedule_timeout(sci->sc_interval); 2465 } 2466 if (nilfs_test_opt(nilfs, DISCARD)) { 2467 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, 2468 sci->sc_nfreesegs); 2469 if (ret) { 2470 printk(KERN_WARNING 2471 "NILFS warning: error %d on discard request, " 2472 "turning discards off for the device\n", ret); 2473 nilfs_clear_opt(nilfs, DISCARD); 2474 } 2475 } 2476 2477 out_unlock: 2478 sci->sc_freesegs = NULL; 2479 sci->sc_nfreesegs = 0; 2480 nilfs_mdt_clear_shadow_map(nilfs->ns_dat); 2481 nilfs_transaction_unlock(sb); 2482 return err; 2483 } 2484 2485 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2486 { 2487 struct nilfs_transaction_info ti; 2488 2489 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2490 nilfs_segctor_construct(sci, mode); 2491 2492 /* 2493 * Unclosed segment should be retried. We do this using sc_timer. 2494 * Timeout of sc_timer will invoke complete construction which leads 2495 * to close the current logical segment. 2496 */ 2497 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2498 nilfs_segctor_start_timer(sci); 2499 2500 nilfs_transaction_unlock(sci->sc_super); 2501 } 2502 2503 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2504 { 2505 int mode = 0; 2506 2507 spin_lock(&sci->sc_state_lock); 2508 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2509 SC_FLUSH_DAT : SC_FLUSH_FILE; 2510 spin_unlock(&sci->sc_state_lock); 2511 2512 if (mode) { 2513 nilfs_segctor_do_construct(sci, mode); 2514 2515 spin_lock(&sci->sc_state_lock); 2516 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2517 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2518 spin_unlock(&sci->sc_state_lock); 2519 } 2520 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2521 } 2522 2523 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2524 { 2525 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2526 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2527 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2528 return SC_FLUSH_FILE; 2529 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2530 return SC_FLUSH_DAT; 2531 } 2532 return SC_LSEG_SR; 2533 } 2534 2535 /** 2536 * nilfs_segctor_thread - main loop of the segment constructor thread. 2537 * @arg: pointer to a struct nilfs_sc_info. 2538 * 2539 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2540 * to execute segment constructions. 2541 */ 2542 static int nilfs_segctor_thread(void *arg) 2543 { 2544 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2545 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2546 int timeout = 0; 2547 2548 sci->sc_timer.data = (unsigned long)current; 2549 sci->sc_timer.function = nilfs_construction_timeout; 2550 2551 /* start sync. */ 2552 sci->sc_task = current; 2553 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2554 printk(KERN_INFO 2555 "segctord starting. Construction interval = %lu seconds, " 2556 "CP frequency < %lu seconds\n", 2557 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2558 2559 spin_lock(&sci->sc_state_lock); 2560 loop: 2561 for (;;) { 2562 int mode; 2563 2564 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2565 goto end_thread; 2566 2567 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2568 mode = SC_LSEG_SR; 2569 else if (sci->sc_flush_request) 2570 mode = nilfs_segctor_flush_mode(sci); 2571 else 2572 break; 2573 2574 spin_unlock(&sci->sc_state_lock); 2575 nilfs_segctor_thread_construct(sci, mode); 2576 spin_lock(&sci->sc_state_lock); 2577 timeout = 0; 2578 } 2579 2580 2581 if (freezing(current)) { 2582 spin_unlock(&sci->sc_state_lock); 2583 try_to_freeze(); 2584 spin_lock(&sci->sc_state_lock); 2585 } else { 2586 DEFINE_WAIT(wait); 2587 int should_sleep = 1; 2588 2589 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2590 TASK_INTERRUPTIBLE); 2591 2592 if (sci->sc_seq_request != sci->sc_seq_done) 2593 should_sleep = 0; 2594 else if (sci->sc_flush_request) 2595 should_sleep = 0; 2596 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2597 should_sleep = time_before(jiffies, 2598 sci->sc_timer.expires); 2599 2600 if (should_sleep) { 2601 spin_unlock(&sci->sc_state_lock); 2602 schedule(); 2603 spin_lock(&sci->sc_state_lock); 2604 } 2605 finish_wait(&sci->sc_wait_daemon, &wait); 2606 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2607 time_after_eq(jiffies, sci->sc_timer.expires)); 2608 2609 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) 2610 set_nilfs_discontinued(nilfs); 2611 } 2612 goto loop; 2613 2614 end_thread: 2615 spin_unlock(&sci->sc_state_lock); 2616 2617 /* end sync. */ 2618 sci->sc_task = NULL; 2619 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2620 return 0; 2621 } 2622 2623 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2624 { 2625 struct task_struct *t; 2626 2627 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2628 if (IS_ERR(t)) { 2629 int err = PTR_ERR(t); 2630 2631 printk(KERN_ERR "NILFS: error %d creating segctord thread\n", 2632 err); 2633 return err; 2634 } 2635 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2636 return 0; 2637 } 2638 2639 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2640 __acquires(&sci->sc_state_lock) 2641 __releases(&sci->sc_state_lock) 2642 { 2643 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2644 2645 while (sci->sc_task) { 2646 wake_up(&sci->sc_wait_daemon); 2647 spin_unlock(&sci->sc_state_lock); 2648 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2649 spin_lock(&sci->sc_state_lock); 2650 } 2651 } 2652 2653 /* 2654 * Setup & clean-up functions 2655 */ 2656 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb, 2657 struct nilfs_root *root) 2658 { 2659 struct the_nilfs *nilfs = sb->s_fs_info; 2660 struct nilfs_sc_info *sci; 2661 2662 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2663 if (!sci) 2664 return NULL; 2665 2666 sci->sc_super = sb; 2667 2668 nilfs_get_root(root); 2669 sci->sc_root = root; 2670 2671 init_waitqueue_head(&sci->sc_wait_request); 2672 init_waitqueue_head(&sci->sc_wait_daemon); 2673 init_waitqueue_head(&sci->sc_wait_task); 2674 spin_lock_init(&sci->sc_state_lock); 2675 INIT_LIST_HEAD(&sci->sc_dirty_files); 2676 INIT_LIST_HEAD(&sci->sc_segbufs); 2677 INIT_LIST_HEAD(&sci->sc_write_logs); 2678 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2679 INIT_LIST_HEAD(&sci->sc_iput_queue); 2680 INIT_WORK(&sci->sc_iput_work, nilfs_iput_work_func); 2681 init_timer(&sci->sc_timer); 2682 2683 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2684 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2685 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2686 2687 if (nilfs->ns_interval) 2688 sci->sc_interval = HZ * nilfs->ns_interval; 2689 if (nilfs->ns_watermark) 2690 sci->sc_watermark = nilfs->ns_watermark; 2691 return sci; 2692 } 2693 2694 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2695 { 2696 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2697 2698 /* 2699 * The segctord thread was stopped and its timer was removed. 2700 * But some tasks remain. 2701 */ 2702 do { 2703 struct nilfs_transaction_info ti; 2704 2705 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2706 ret = nilfs_segctor_construct(sci, SC_LSEG_SR); 2707 nilfs_transaction_unlock(sci->sc_super); 2708 2709 flush_work(&sci->sc_iput_work); 2710 2711 } while (ret && retrycount-- > 0); 2712 } 2713 2714 /** 2715 * nilfs_segctor_destroy - destroy the segment constructor. 2716 * @sci: nilfs_sc_info 2717 * 2718 * nilfs_segctor_destroy() kills the segctord thread and frees 2719 * the nilfs_sc_info struct. 2720 * Caller must hold the segment semaphore. 2721 */ 2722 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2723 { 2724 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2725 int flag; 2726 2727 up_write(&nilfs->ns_segctor_sem); 2728 2729 spin_lock(&sci->sc_state_lock); 2730 nilfs_segctor_kill_thread(sci); 2731 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2732 || sci->sc_seq_request != sci->sc_seq_done); 2733 spin_unlock(&sci->sc_state_lock); 2734 2735 if (flush_work(&sci->sc_iput_work)) 2736 flag = true; 2737 2738 if (flag || !nilfs_segctor_confirm(sci)) 2739 nilfs_segctor_write_out(sci); 2740 2741 if (!list_empty(&sci->sc_dirty_files)) { 2742 nilfs_warning(sci->sc_super, __func__, 2743 "dirty file(s) after the final construction"); 2744 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1); 2745 } 2746 2747 if (!list_empty(&sci->sc_iput_queue)) { 2748 nilfs_warning(sci->sc_super, __func__, 2749 "iput queue is not empty"); 2750 nilfs_dispose_list(nilfs, &sci->sc_iput_queue, 1); 2751 } 2752 2753 WARN_ON(!list_empty(&sci->sc_segbufs)); 2754 WARN_ON(!list_empty(&sci->sc_write_logs)); 2755 2756 nilfs_put_root(sci->sc_root); 2757 2758 down_write(&nilfs->ns_segctor_sem); 2759 2760 del_timer_sync(&sci->sc_timer); 2761 kfree(sci); 2762 } 2763 2764 /** 2765 * nilfs_attach_log_writer - attach log writer 2766 * @sb: super block instance 2767 * @root: root object of the current filesystem tree 2768 * 2769 * This allocates a log writer object, initializes it, and starts the 2770 * log writer. 2771 * 2772 * Return Value: On success, 0 is returned. On error, one of the following 2773 * negative error code is returned. 2774 * 2775 * %-ENOMEM - Insufficient memory available. 2776 */ 2777 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root) 2778 { 2779 struct the_nilfs *nilfs = sb->s_fs_info; 2780 int err; 2781 2782 if (nilfs->ns_writer) { 2783 /* 2784 * This happens if the filesystem was remounted 2785 * read/write after nilfs_error degenerated it into a 2786 * read-only mount. 2787 */ 2788 nilfs_detach_log_writer(sb); 2789 } 2790 2791 nilfs->ns_writer = nilfs_segctor_new(sb, root); 2792 if (!nilfs->ns_writer) 2793 return -ENOMEM; 2794 2795 err = nilfs_segctor_start_thread(nilfs->ns_writer); 2796 if (err) { 2797 kfree(nilfs->ns_writer); 2798 nilfs->ns_writer = NULL; 2799 } 2800 return err; 2801 } 2802 2803 /** 2804 * nilfs_detach_log_writer - destroy log writer 2805 * @sb: super block instance 2806 * 2807 * This kills log writer daemon, frees the log writer object, and 2808 * destroys list of dirty files. 2809 */ 2810 void nilfs_detach_log_writer(struct super_block *sb) 2811 { 2812 struct the_nilfs *nilfs = sb->s_fs_info; 2813 LIST_HEAD(garbage_list); 2814 2815 down_write(&nilfs->ns_segctor_sem); 2816 if (nilfs->ns_writer) { 2817 nilfs_segctor_destroy(nilfs->ns_writer); 2818 nilfs->ns_writer = NULL; 2819 } 2820 2821 /* Force to free the list of dirty files */ 2822 spin_lock(&nilfs->ns_inode_lock); 2823 if (!list_empty(&nilfs->ns_dirty_files)) { 2824 list_splice_init(&nilfs->ns_dirty_files, &garbage_list); 2825 nilfs_warning(sb, __func__, 2826 "Hit dirty file after stopped log writer"); 2827 } 2828 spin_unlock(&nilfs->ns_inode_lock); 2829 up_write(&nilfs->ns_segctor_sem); 2830 2831 nilfs_dispose_list(nilfs, &garbage_list, 1); 2832 } 2833