1 /* 2 * segment.c - NILFS segment constructor. 3 * 4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Ryusuke Konishi <ryusuke@osrg.net> 21 * 22 */ 23 24 #include <linux/pagemap.h> 25 #include <linux/buffer_head.h> 26 #include <linux/writeback.h> 27 #include <linux/bio.h> 28 #include <linux/completion.h> 29 #include <linux/blkdev.h> 30 #include <linux/backing-dev.h> 31 #include <linux/freezer.h> 32 #include <linux/kthread.h> 33 #include <linux/crc32.h> 34 #include <linux/pagevec.h> 35 #include <linux/slab.h> 36 #include "nilfs.h" 37 #include "btnode.h" 38 #include "page.h" 39 #include "segment.h" 40 #include "sufile.h" 41 #include "cpfile.h" 42 #include "ifile.h" 43 #include "segbuf.h" 44 45 46 /* 47 * Segment constructor 48 */ 49 #define SC_N_INODEVEC 16 /* Size of locally allocated inode vector */ 50 51 #define SC_MAX_SEGDELTA 64 /* Upper limit of the number of segments 52 appended in collection retry loop */ 53 54 /* Construction mode */ 55 enum { 56 SC_LSEG_SR = 1, /* Make a logical segment having a super root */ 57 SC_LSEG_DSYNC, /* Flush data blocks of a given file and make 58 a logical segment without a super root */ 59 SC_FLUSH_FILE, /* Flush data files, leads to segment writes without 60 creating a checkpoint */ 61 SC_FLUSH_DAT, /* Flush DAT file. This also creates segments without 62 a checkpoint */ 63 }; 64 65 /* Stage numbers of dirty block collection */ 66 enum { 67 NILFS_ST_INIT = 0, 68 NILFS_ST_GC, /* Collecting dirty blocks for GC */ 69 NILFS_ST_FILE, 70 NILFS_ST_IFILE, 71 NILFS_ST_CPFILE, 72 NILFS_ST_SUFILE, 73 NILFS_ST_DAT, 74 NILFS_ST_SR, /* Super root */ 75 NILFS_ST_DSYNC, /* Data sync blocks */ 76 NILFS_ST_DONE, 77 }; 78 79 /* State flags of collection */ 80 #define NILFS_CF_NODE 0x0001 /* Collecting node blocks */ 81 #define NILFS_CF_IFILE_STARTED 0x0002 /* IFILE stage has started */ 82 #define NILFS_CF_SUFREED 0x0004 /* segment usages has been freed */ 83 #define NILFS_CF_HISTORY_MASK (NILFS_CF_IFILE_STARTED | NILFS_CF_SUFREED) 84 85 /* Operations depending on the construction mode and file type */ 86 struct nilfs_sc_operations { 87 int (*collect_data)(struct nilfs_sc_info *, struct buffer_head *, 88 struct inode *); 89 int (*collect_node)(struct nilfs_sc_info *, struct buffer_head *, 90 struct inode *); 91 int (*collect_bmap)(struct nilfs_sc_info *, struct buffer_head *, 92 struct inode *); 93 void (*write_data_binfo)(struct nilfs_sc_info *, 94 struct nilfs_segsum_pointer *, 95 union nilfs_binfo *); 96 void (*write_node_binfo)(struct nilfs_sc_info *, 97 struct nilfs_segsum_pointer *, 98 union nilfs_binfo *); 99 }; 100 101 /* 102 * Other definitions 103 */ 104 static void nilfs_segctor_start_timer(struct nilfs_sc_info *); 105 static void nilfs_segctor_do_flush(struct nilfs_sc_info *, int); 106 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *); 107 static void nilfs_dispose_list(struct the_nilfs *, struct list_head *, int); 108 109 #define nilfs_cnt32_gt(a, b) \ 110 (typecheck(__u32, a) && typecheck(__u32, b) && \ 111 ((__s32)(b) - (__s32)(a) < 0)) 112 #define nilfs_cnt32_ge(a, b) \ 113 (typecheck(__u32, a) && typecheck(__u32, b) && \ 114 ((__s32)(a) - (__s32)(b) >= 0)) 115 #define nilfs_cnt32_lt(a, b) nilfs_cnt32_gt(b, a) 116 #define nilfs_cnt32_le(a, b) nilfs_cnt32_ge(b, a) 117 118 static int nilfs_prepare_segment_lock(struct nilfs_transaction_info *ti) 119 { 120 struct nilfs_transaction_info *cur_ti = current->journal_info; 121 void *save = NULL; 122 123 if (cur_ti) { 124 if (cur_ti->ti_magic == NILFS_TI_MAGIC) 125 return ++cur_ti->ti_count; 126 else { 127 /* 128 * If journal_info field is occupied by other FS, 129 * it is saved and will be restored on 130 * nilfs_transaction_commit(). 131 */ 132 printk(KERN_WARNING 133 "NILFS warning: journal info from a different " 134 "FS\n"); 135 save = current->journal_info; 136 } 137 } 138 if (!ti) { 139 ti = kmem_cache_alloc(nilfs_transaction_cachep, GFP_NOFS); 140 if (!ti) 141 return -ENOMEM; 142 ti->ti_flags = NILFS_TI_DYNAMIC_ALLOC; 143 } else { 144 ti->ti_flags = 0; 145 } 146 ti->ti_count = 0; 147 ti->ti_save = save; 148 ti->ti_magic = NILFS_TI_MAGIC; 149 current->journal_info = ti; 150 return 0; 151 } 152 153 /** 154 * nilfs_transaction_begin - start indivisible file operations. 155 * @sb: super block 156 * @ti: nilfs_transaction_info 157 * @vacancy_check: flags for vacancy rate checks 158 * 159 * nilfs_transaction_begin() acquires a reader/writer semaphore, called 160 * the segment semaphore, to make a segment construction and write tasks 161 * exclusive. The function is used with nilfs_transaction_commit() in pairs. 162 * The region enclosed by these two functions can be nested. To avoid a 163 * deadlock, the semaphore is only acquired or released in the outermost call. 164 * 165 * This function allocates a nilfs_transaction_info struct to keep context 166 * information on it. It is initialized and hooked onto the current task in 167 * the outermost call. If a pre-allocated struct is given to @ti, it is used 168 * instead; otherwise a new struct is assigned from a slab. 169 * 170 * When @vacancy_check flag is set, this function will check the amount of 171 * free space, and will wait for the GC to reclaim disk space if low capacity. 172 * 173 * Return Value: On success, 0 is returned. On error, one of the following 174 * negative error code is returned. 175 * 176 * %-ENOMEM - Insufficient memory available. 177 * 178 * %-ENOSPC - No space left on device 179 */ 180 int nilfs_transaction_begin(struct super_block *sb, 181 struct nilfs_transaction_info *ti, 182 int vacancy_check) 183 { 184 struct the_nilfs *nilfs; 185 int ret = nilfs_prepare_segment_lock(ti); 186 187 if (unlikely(ret < 0)) 188 return ret; 189 if (ret > 0) 190 return 0; 191 192 sb_start_intwrite(sb); 193 194 nilfs = sb->s_fs_info; 195 down_read(&nilfs->ns_segctor_sem); 196 if (vacancy_check && nilfs_near_disk_full(nilfs)) { 197 up_read(&nilfs->ns_segctor_sem); 198 ret = -ENOSPC; 199 goto failed; 200 } 201 return 0; 202 203 failed: 204 ti = current->journal_info; 205 current->journal_info = ti->ti_save; 206 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 207 kmem_cache_free(nilfs_transaction_cachep, ti); 208 sb_end_intwrite(sb); 209 return ret; 210 } 211 212 /** 213 * nilfs_transaction_commit - commit indivisible file operations. 214 * @sb: super block 215 * 216 * nilfs_transaction_commit() releases the read semaphore which is 217 * acquired by nilfs_transaction_begin(). This is only performed 218 * in outermost call of this function. If a commit flag is set, 219 * nilfs_transaction_commit() sets a timer to start the segment 220 * constructor. If a sync flag is set, it starts construction 221 * directly. 222 */ 223 int nilfs_transaction_commit(struct super_block *sb) 224 { 225 struct nilfs_transaction_info *ti = current->journal_info; 226 struct the_nilfs *nilfs = sb->s_fs_info; 227 int err = 0; 228 229 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 230 ti->ti_flags |= NILFS_TI_COMMIT; 231 if (ti->ti_count > 0) { 232 ti->ti_count--; 233 return 0; 234 } 235 if (nilfs->ns_writer) { 236 struct nilfs_sc_info *sci = nilfs->ns_writer; 237 238 if (ti->ti_flags & NILFS_TI_COMMIT) 239 nilfs_segctor_start_timer(sci); 240 if (atomic_read(&nilfs->ns_ndirtyblks) > sci->sc_watermark) 241 nilfs_segctor_do_flush(sci, 0); 242 } 243 up_read(&nilfs->ns_segctor_sem); 244 current->journal_info = ti->ti_save; 245 246 if (ti->ti_flags & NILFS_TI_SYNC) 247 err = nilfs_construct_segment(sb); 248 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 249 kmem_cache_free(nilfs_transaction_cachep, ti); 250 sb_end_intwrite(sb); 251 return err; 252 } 253 254 void nilfs_transaction_abort(struct super_block *sb) 255 { 256 struct nilfs_transaction_info *ti = current->journal_info; 257 struct the_nilfs *nilfs = sb->s_fs_info; 258 259 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 260 if (ti->ti_count > 0) { 261 ti->ti_count--; 262 return; 263 } 264 up_read(&nilfs->ns_segctor_sem); 265 266 current->journal_info = ti->ti_save; 267 if (ti->ti_flags & NILFS_TI_DYNAMIC_ALLOC) 268 kmem_cache_free(nilfs_transaction_cachep, ti); 269 sb_end_intwrite(sb); 270 } 271 272 void nilfs_relax_pressure_in_lock(struct super_block *sb) 273 { 274 struct the_nilfs *nilfs = sb->s_fs_info; 275 struct nilfs_sc_info *sci = nilfs->ns_writer; 276 277 if (!sci || !sci->sc_flush_request) 278 return; 279 280 set_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 281 up_read(&nilfs->ns_segctor_sem); 282 283 down_write(&nilfs->ns_segctor_sem); 284 if (sci->sc_flush_request && 285 test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) { 286 struct nilfs_transaction_info *ti = current->journal_info; 287 288 ti->ti_flags |= NILFS_TI_WRITER; 289 nilfs_segctor_do_immediate_flush(sci); 290 ti->ti_flags &= ~NILFS_TI_WRITER; 291 } 292 downgrade_write(&nilfs->ns_segctor_sem); 293 } 294 295 static void nilfs_transaction_lock(struct super_block *sb, 296 struct nilfs_transaction_info *ti, 297 int gcflag) 298 { 299 struct nilfs_transaction_info *cur_ti = current->journal_info; 300 struct the_nilfs *nilfs = sb->s_fs_info; 301 struct nilfs_sc_info *sci = nilfs->ns_writer; 302 303 WARN_ON(cur_ti); 304 ti->ti_flags = NILFS_TI_WRITER; 305 ti->ti_count = 0; 306 ti->ti_save = cur_ti; 307 ti->ti_magic = NILFS_TI_MAGIC; 308 INIT_LIST_HEAD(&ti->ti_garbage); 309 current->journal_info = ti; 310 311 for (;;) { 312 down_write(&nilfs->ns_segctor_sem); 313 if (!test_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags)) 314 break; 315 316 nilfs_segctor_do_immediate_flush(sci); 317 318 up_write(&nilfs->ns_segctor_sem); 319 yield(); 320 } 321 if (gcflag) 322 ti->ti_flags |= NILFS_TI_GC; 323 } 324 325 static void nilfs_transaction_unlock(struct super_block *sb) 326 { 327 struct nilfs_transaction_info *ti = current->journal_info; 328 struct the_nilfs *nilfs = sb->s_fs_info; 329 330 BUG_ON(ti == NULL || ti->ti_magic != NILFS_TI_MAGIC); 331 BUG_ON(ti->ti_count > 0); 332 333 up_write(&nilfs->ns_segctor_sem); 334 current->journal_info = ti->ti_save; 335 if (!list_empty(&ti->ti_garbage)) 336 nilfs_dispose_list(nilfs, &ti->ti_garbage, 0); 337 } 338 339 static void *nilfs_segctor_map_segsum_entry(struct nilfs_sc_info *sci, 340 struct nilfs_segsum_pointer *ssp, 341 unsigned bytes) 342 { 343 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 344 unsigned blocksize = sci->sc_super->s_blocksize; 345 void *p; 346 347 if (unlikely(ssp->offset + bytes > blocksize)) { 348 ssp->offset = 0; 349 BUG_ON(NILFS_SEGBUF_BH_IS_LAST(ssp->bh, 350 &segbuf->sb_segsum_buffers)); 351 ssp->bh = NILFS_SEGBUF_NEXT_BH(ssp->bh); 352 } 353 p = ssp->bh->b_data + ssp->offset; 354 ssp->offset += bytes; 355 return p; 356 } 357 358 /** 359 * nilfs_segctor_reset_segment_buffer - reset the current segment buffer 360 * @sci: nilfs_sc_info 361 */ 362 static int nilfs_segctor_reset_segment_buffer(struct nilfs_sc_info *sci) 363 { 364 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 365 struct buffer_head *sumbh; 366 unsigned sumbytes; 367 unsigned flags = 0; 368 int err; 369 370 if (nilfs_doing_gc()) 371 flags = NILFS_SS_GC; 372 err = nilfs_segbuf_reset(segbuf, flags, sci->sc_seg_ctime, sci->sc_cno); 373 if (unlikely(err)) 374 return err; 375 376 sumbh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 377 sumbytes = segbuf->sb_sum.sumbytes; 378 sci->sc_finfo_ptr.bh = sumbh; sci->sc_finfo_ptr.offset = sumbytes; 379 sci->sc_binfo_ptr.bh = sumbh; sci->sc_binfo_ptr.offset = sumbytes; 380 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 381 return 0; 382 } 383 384 static int nilfs_segctor_feed_segment(struct nilfs_sc_info *sci) 385 { 386 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 387 if (NILFS_SEGBUF_IS_LAST(sci->sc_curseg, &sci->sc_segbufs)) 388 return -E2BIG; /* The current segment is filled up 389 (internal code) */ 390 sci->sc_curseg = NILFS_NEXT_SEGBUF(sci->sc_curseg); 391 return nilfs_segctor_reset_segment_buffer(sci); 392 } 393 394 static int nilfs_segctor_add_super_root(struct nilfs_sc_info *sci) 395 { 396 struct nilfs_segment_buffer *segbuf = sci->sc_curseg; 397 int err; 398 399 if (segbuf->sb_sum.nblocks >= segbuf->sb_rest_blocks) { 400 err = nilfs_segctor_feed_segment(sci); 401 if (err) 402 return err; 403 segbuf = sci->sc_curseg; 404 } 405 err = nilfs_segbuf_extend_payload(segbuf, &segbuf->sb_super_root); 406 if (likely(!err)) 407 segbuf->sb_sum.flags |= NILFS_SS_SR; 408 return err; 409 } 410 411 /* 412 * Functions for making segment summary and payloads 413 */ 414 static int nilfs_segctor_segsum_block_required( 415 struct nilfs_sc_info *sci, const struct nilfs_segsum_pointer *ssp, 416 unsigned binfo_size) 417 { 418 unsigned blocksize = sci->sc_super->s_blocksize; 419 /* Size of finfo and binfo is enough small against blocksize */ 420 421 return ssp->offset + binfo_size + 422 (!sci->sc_blk_cnt ? sizeof(struct nilfs_finfo) : 0) > 423 blocksize; 424 } 425 426 static void nilfs_segctor_begin_finfo(struct nilfs_sc_info *sci, 427 struct inode *inode) 428 { 429 sci->sc_curseg->sb_sum.nfinfo++; 430 sci->sc_binfo_ptr = sci->sc_finfo_ptr; 431 nilfs_segctor_map_segsum_entry( 432 sci, &sci->sc_binfo_ptr, sizeof(struct nilfs_finfo)); 433 434 if (NILFS_I(inode)->i_root && 435 !test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 436 set_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 437 /* skip finfo */ 438 } 439 440 static void nilfs_segctor_end_finfo(struct nilfs_sc_info *sci, 441 struct inode *inode) 442 { 443 struct nilfs_finfo *finfo; 444 struct nilfs_inode_info *ii; 445 struct nilfs_segment_buffer *segbuf; 446 __u64 cno; 447 448 if (sci->sc_blk_cnt == 0) 449 return; 450 451 ii = NILFS_I(inode); 452 453 if (test_bit(NILFS_I_GCINODE, &ii->i_state)) 454 cno = ii->i_cno; 455 else if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) 456 cno = 0; 457 else 458 cno = sci->sc_cno; 459 460 finfo = nilfs_segctor_map_segsum_entry(sci, &sci->sc_finfo_ptr, 461 sizeof(*finfo)); 462 finfo->fi_ino = cpu_to_le64(inode->i_ino); 463 finfo->fi_nblocks = cpu_to_le32(sci->sc_blk_cnt); 464 finfo->fi_ndatablk = cpu_to_le32(sci->sc_datablk_cnt); 465 finfo->fi_cno = cpu_to_le64(cno); 466 467 segbuf = sci->sc_curseg; 468 segbuf->sb_sum.sumbytes = sci->sc_binfo_ptr.offset + 469 sci->sc_super->s_blocksize * (segbuf->sb_sum.nsumblk - 1); 470 sci->sc_finfo_ptr = sci->sc_binfo_ptr; 471 sci->sc_blk_cnt = sci->sc_datablk_cnt = 0; 472 } 473 474 static int nilfs_segctor_add_file_block(struct nilfs_sc_info *sci, 475 struct buffer_head *bh, 476 struct inode *inode, 477 unsigned binfo_size) 478 { 479 struct nilfs_segment_buffer *segbuf; 480 int required, err = 0; 481 482 retry: 483 segbuf = sci->sc_curseg; 484 required = nilfs_segctor_segsum_block_required( 485 sci, &sci->sc_binfo_ptr, binfo_size); 486 if (segbuf->sb_sum.nblocks + required + 1 > segbuf->sb_rest_blocks) { 487 nilfs_segctor_end_finfo(sci, inode); 488 err = nilfs_segctor_feed_segment(sci); 489 if (err) 490 return err; 491 goto retry; 492 } 493 if (unlikely(required)) { 494 err = nilfs_segbuf_extend_segsum(segbuf); 495 if (unlikely(err)) 496 goto failed; 497 } 498 if (sci->sc_blk_cnt == 0) 499 nilfs_segctor_begin_finfo(sci, inode); 500 501 nilfs_segctor_map_segsum_entry(sci, &sci->sc_binfo_ptr, binfo_size); 502 /* Substitution to vblocknr is delayed until update_blocknr() */ 503 nilfs_segbuf_add_file_buffer(segbuf, bh); 504 sci->sc_blk_cnt++; 505 failed: 506 return err; 507 } 508 509 /* 510 * Callback functions that enumerate, mark, and collect dirty blocks 511 */ 512 static int nilfs_collect_file_data(struct nilfs_sc_info *sci, 513 struct buffer_head *bh, struct inode *inode) 514 { 515 int err; 516 517 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 518 if (err < 0) 519 return err; 520 521 err = nilfs_segctor_add_file_block(sci, bh, inode, 522 sizeof(struct nilfs_binfo_v)); 523 if (!err) 524 sci->sc_datablk_cnt++; 525 return err; 526 } 527 528 static int nilfs_collect_file_node(struct nilfs_sc_info *sci, 529 struct buffer_head *bh, 530 struct inode *inode) 531 { 532 return nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 533 } 534 535 static int nilfs_collect_file_bmap(struct nilfs_sc_info *sci, 536 struct buffer_head *bh, 537 struct inode *inode) 538 { 539 WARN_ON(!buffer_dirty(bh)); 540 return nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 541 } 542 543 static void nilfs_write_file_data_binfo(struct nilfs_sc_info *sci, 544 struct nilfs_segsum_pointer *ssp, 545 union nilfs_binfo *binfo) 546 { 547 struct nilfs_binfo_v *binfo_v = nilfs_segctor_map_segsum_entry( 548 sci, ssp, sizeof(*binfo_v)); 549 *binfo_v = binfo->bi_v; 550 } 551 552 static void nilfs_write_file_node_binfo(struct nilfs_sc_info *sci, 553 struct nilfs_segsum_pointer *ssp, 554 union nilfs_binfo *binfo) 555 { 556 __le64 *vblocknr = nilfs_segctor_map_segsum_entry( 557 sci, ssp, sizeof(*vblocknr)); 558 *vblocknr = binfo->bi_v.bi_vblocknr; 559 } 560 561 static struct nilfs_sc_operations nilfs_sc_file_ops = { 562 .collect_data = nilfs_collect_file_data, 563 .collect_node = nilfs_collect_file_node, 564 .collect_bmap = nilfs_collect_file_bmap, 565 .write_data_binfo = nilfs_write_file_data_binfo, 566 .write_node_binfo = nilfs_write_file_node_binfo, 567 }; 568 569 static int nilfs_collect_dat_data(struct nilfs_sc_info *sci, 570 struct buffer_head *bh, struct inode *inode) 571 { 572 int err; 573 574 err = nilfs_bmap_propagate(NILFS_I(inode)->i_bmap, bh); 575 if (err < 0) 576 return err; 577 578 err = nilfs_segctor_add_file_block(sci, bh, inode, sizeof(__le64)); 579 if (!err) 580 sci->sc_datablk_cnt++; 581 return err; 582 } 583 584 static int nilfs_collect_dat_bmap(struct nilfs_sc_info *sci, 585 struct buffer_head *bh, struct inode *inode) 586 { 587 WARN_ON(!buffer_dirty(bh)); 588 return nilfs_segctor_add_file_block(sci, bh, inode, 589 sizeof(struct nilfs_binfo_dat)); 590 } 591 592 static void nilfs_write_dat_data_binfo(struct nilfs_sc_info *sci, 593 struct nilfs_segsum_pointer *ssp, 594 union nilfs_binfo *binfo) 595 { 596 __le64 *blkoff = nilfs_segctor_map_segsum_entry(sci, ssp, 597 sizeof(*blkoff)); 598 *blkoff = binfo->bi_dat.bi_blkoff; 599 } 600 601 static void nilfs_write_dat_node_binfo(struct nilfs_sc_info *sci, 602 struct nilfs_segsum_pointer *ssp, 603 union nilfs_binfo *binfo) 604 { 605 struct nilfs_binfo_dat *binfo_dat = 606 nilfs_segctor_map_segsum_entry(sci, ssp, sizeof(*binfo_dat)); 607 *binfo_dat = binfo->bi_dat; 608 } 609 610 static struct nilfs_sc_operations nilfs_sc_dat_ops = { 611 .collect_data = nilfs_collect_dat_data, 612 .collect_node = nilfs_collect_file_node, 613 .collect_bmap = nilfs_collect_dat_bmap, 614 .write_data_binfo = nilfs_write_dat_data_binfo, 615 .write_node_binfo = nilfs_write_dat_node_binfo, 616 }; 617 618 static struct nilfs_sc_operations nilfs_sc_dsync_ops = { 619 .collect_data = nilfs_collect_file_data, 620 .collect_node = NULL, 621 .collect_bmap = NULL, 622 .write_data_binfo = nilfs_write_file_data_binfo, 623 .write_node_binfo = NULL, 624 }; 625 626 static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode, 627 struct list_head *listp, 628 size_t nlimit, 629 loff_t start, loff_t end) 630 { 631 struct address_space *mapping = inode->i_mapping; 632 struct pagevec pvec; 633 pgoff_t index = 0, last = ULONG_MAX; 634 size_t ndirties = 0; 635 int i; 636 637 if (unlikely(start != 0 || end != LLONG_MAX)) { 638 /* 639 * A valid range is given for sync-ing data pages. The 640 * range is rounded to per-page; extra dirty buffers 641 * may be included if blocksize < pagesize. 642 */ 643 index = start >> PAGE_SHIFT; 644 last = end >> PAGE_SHIFT; 645 } 646 pagevec_init(&pvec, 0); 647 repeat: 648 if (unlikely(index > last) || 649 !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 650 min_t(pgoff_t, last - index, 651 PAGEVEC_SIZE - 1) + 1)) 652 return ndirties; 653 654 for (i = 0; i < pagevec_count(&pvec); i++) { 655 struct buffer_head *bh, *head; 656 struct page *page = pvec.pages[i]; 657 658 if (unlikely(page->index > last)) 659 break; 660 661 lock_page(page); 662 if (!page_has_buffers(page)) 663 create_empty_buffers(page, 1 << inode->i_blkbits, 0); 664 unlock_page(page); 665 666 bh = head = page_buffers(page); 667 do { 668 if (!buffer_dirty(bh)) 669 continue; 670 get_bh(bh); 671 list_add_tail(&bh->b_assoc_buffers, listp); 672 ndirties++; 673 if (unlikely(ndirties >= nlimit)) { 674 pagevec_release(&pvec); 675 cond_resched(); 676 return ndirties; 677 } 678 } while (bh = bh->b_this_page, bh != head); 679 } 680 pagevec_release(&pvec); 681 cond_resched(); 682 goto repeat; 683 } 684 685 static void nilfs_lookup_dirty_node_buffers(struct inode *inode, 686 struct list_head *listp) 687 { 688 struct nilfs_inode_info *ii = NILFS_I(inode); 689 struct address_space *mapping = &ii->i_btnode_cache; 690 struct pagevec pvec; 691 struct buffer_head *bh, *head; 692 unsigned int i; 693 pgoff_t index = 0; 694 695 pagevec_init(&pvec, 0); 696 697 while (pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY, 698 PAGEVEC_SIZE)) { 699 for (i = 0; i < pagevec_count(&pvec); i++) { 700 bh = head = page_buffers(pvec.pages[i]); 701 do { 702 if (buffer_dirty(bh)) { 703 get_bh(bh); 704 list_add_tail(&bh->b_assoc_buffers, 705 listp); 706 } 707 bh = bh->b_this_page; 708 } while (bh != head); 709 } 710 pagevec_release(&pvec); 711 cond_resched(); 712 } 713 } 714 715 static void nilfs_dispose_list(struct the_nilfs *nilfs, 716 struct list_head *head, int force) 717 { 718 struct nilfs_inode_info *ii, *n; 719 struct nilfs_inode_info *ivec[SC_N_INODEVEC], **pii; 720 unsigned nv = 0; 721 722 while (!list_empty(head)) { 723 spin_lock(&nilfs->ns_inode_lock); 724 list_for_each_entry_safe(ii, n, head, i_dirty) { 725 list_del_init(&ii->i_dirty); 726 if (force) { 727 if (unlikely(ii->i_bh)) { 728 brelse(ii->i_bh); 729 ii->i_bh = NULL; 730 } 731 } else if (test_bit(NILFS_I_DIRTY, &ii->i_state)) { 732 set_bit(NILFS_I_QUEUED, &ii->i_state); 733 list_add_tail(&ii->i_dirty, 734 &nilfs->ns_dirty_files); 735 continue; 736 } 737 ivec[nv++] = ii; 738 if (nv == SC_N_INODEVEC) 739 break; 740 } 741 spin_unlock(&nilfs->ns_inode_lock); 742 743 for (pii = ivec; nv > 0; pii++, nv--) 744 iput(&(*pii)->vfs_inode); 745 } 746 } 747 748 static int nilfs_test_metadata_dirty(struct the_nilfs *nilfs, 749 struct nilfs_root *root) 750 { 751 int ret = 0; 752 753 if (nilfs_mdt_fetch_dirty(root->ifile)) 754 ret++; 755 if (nilfs_mdt_fetch_dirty(nilfs->ns_cpfile)) 756 ret++; 757 if (nilfs_mdt_fetch_dirty(nilfs->ns_sufile)) 758 ret++; 759 if ((ret || nilfs_doing_gc()) && nilfs_mdt_fetch_dirty(nilfs->ns_dat)) 760 ret++; 761 return ret; 762 } 763 764 static int nilfs_segctor_clean(struct nilfs_sc_info *sci) 765 { 766 return list_empty(&sci->sc_dirty_files) && 767 !test_bit(NILFS_SC_DIRTY, &sci->sc_flags) && 768 sci->sc_nfreesegs == 0 && 769 (!nilfs_doing_gc() || list_empty(&sci->sc_gc_inodes)); 770 } 771 772 static int nilfs_segctor_confirm(struct nilfs_sc_info *sci) 773 { 774 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 775 int ret = 0; 776 777 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 778 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 779 780 spin_lock(&nilfs->ns_inode_lock); 781 if (list_empty(&nilfs->ns_dirty_files) && nilfs_segctor_clean(sci)) 782 ret++; 783 784 spin_unlock(&nilfs->ns_inode_lock); 785 return ret; 786 } 787 788 static void nilfs_segctor_clear_metadata_dirty(struct nilfs_sc_info *sci) 789 { 790 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 791 792 nilfs_mdt_clear_dirty(sci->sc_root->ifile); 793 nilfs_mdt_clear_dirty(nilfs->ns_cpfile); 794 nilfs_mdt_clear_dirty(nilfs->ns_sufile); 795 nilfs_mdt_clear_dirty(nilfs->ns_dat); 796 } 797 798 static int nilfs_segctor_create_checkpoint(struct nilfs_sc_info *sci) 799 { 800 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 801 struct buffer_head *bh_cp; 802 struct nilfs_checkpoint *raw_cp; 803 int err; 804 805 /* XXX: this interface will be changed */ 806 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 1, 807 &raw_cp, &bh_cp); 808 if (likely(!err)) { 809 /* The following code is duplicated with cpfile. But, it is 810 needed to collect the checkpoint even if it was not newly 811 created */ 812 mark_buffer_dirty(bh_cp); 813 nilfs_mdt_mark_dirty(nilfs->ns_cpfile); 814 nilfs_cpfile_put_checkpoint( 815 nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 816 } else 817 WARN_ON(err == -EINVAL || err == -ENOENT); 818 819 return err; 820 } 821 822 static int nilfs_segctor_fill_in_checkpoint(struct nilfs_sc_info *sci) 823 { 824 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 825 struct buffer_head *bh_cp; 826 struct nilfs_checkpoint *raw_cp; 827 int err; 828 829 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, 0, 830 &raw_cp, &bh_cp); 831 if (unlikely(err)) { 832 WARN_ON(err == -EINVAL || err == -ENOENT); 833 goto failed_ibh; 834 } 835 raw_cp->cp_snapshot_list.ssl_next = 0; 836 raw_cp->cp_snapshot_list.ssl_prev = 0; 837 raw_cp->cp_inodes_count = 838 cpu_to_le64(atomic64_read(&sci->sc_root->inodes_count)); 839 raw_cp->cp_blocks_count = 840 cpu_to_le64(atomic64_read(&sci->sc_root->blocks_count)); 841 raw_cp->cp_nblk_inc = 842 cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc); 843 raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime); 844 raw_cp->cp_cno = cpu_to_le64(nilfs->ns_cno); 845 846 if (test_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags)) 847 nilfs_checkpoint_clear_minor(raw_cp); 848 else 849 nilfs_checkpoint_set_minor(raw_cp); 850 851 nilfs_write_inode_common(sci->sc_root->ifile, 852 &raw_cp->cp_ifile_inode, 1); 853 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, nilfs->ns_cno, bh_cp); 854 return 0; 855 856 failed_ibh: 857 return err; 858 } 859 860 static void nilfs_fill_in_file_bmap(struct inode *ifile, 861 struct nilfs_inode_info *ii) 862 863 { 864 struct buffer_head *ibh; 865 struct nilfs_inode *raw_inode; 866 867 if (test_bit(NILFS_I_BMAP, &ii->i_state)) { 868 ibh = ii->i_bh; 869 BUG_ON(!ibh); 870 raw_inode = nilfs_ifile_map_inode(ifile, ii->vfs_inode.i_ino, 871 ibh); 872 nilfs_bmap_write(ii->i_bmap, raw_inode); 873 nilfs_ifile_unmap_inode(ifile, ii->vfs_inode.i_ino, ibh); 874 } 875 } 876 877 static void nilfs_segctor_fill_in_file_bmap(struct nilfs_sc_info *sci) 878 { 879 struct nilfs_inode_info *ii; 880 881 list_for_each_entry(ii, &sci->sc_dirty_files, i_dirty) { 882 nilfs_fill_in_file_bmap(sci->sc_root->ifile, ii); 883 set_bit(NILFS_I_COLLECTED, &ii->i_state); 884 } 885 } 886 887 static void nilfs_segctor_fill_in_super_root(struct nilfs_sc_info *sci, 888 struct the_nilfs *nilfs) 889 { 890 struct buffer_head *bh_sr; 891 struct nilfs_super_root *raw_sr; 892 unsigned isz, srsz; 893 894 bh_sr = NILFS_LAST_SEGBUF(&sci->sc_segbufs)->sb_super_root; 895 raw_sr = (struct nilfs_super_root *)bh_sr->b_data; 896 isz = nilfs->ns_inode_size; 897 srsz = NILFS_SR_BYTES(isz); 898 899 raw_sr->sr_bytes = cpu_to_le16(srsz); 900 raw_sr->sr_nongc_ctime 901 = cpu_to_le64(nilfs_doing_gc() ? 902 nilfs->ns_nongc_ctime : sci->sc_seg_ctime); 903 raw_sr->sr_flags = 0; 904 905 nilfs_write_inode_common(nilfs->ns_dat, (void *)raw_sr + 906 NILFS_SR_DAT_OFFSET(isz), 1); 907 nilfs_write_inode_common(nilfs->ns_cpfile, (void *)raw_sr + 908 NILFS_SR_CPFILE_OFFSET(isz), 1); 909 nilfs_write_inode_common(nilfs->ns_sufile, (void *)raw_sr + 910 NILFS_SR_SUFILE_OFFSET(isz), 1); 911 memset((void *)raw_sr + srsz, 0, nilfs->ns_blocksize - srsz); 912 } 913 914 static void nilfs_redirty_inodes(struct list_head *head) 915 { 916 struct nilfs_inode_info *ii; 917 918 list_for_each_entry(ii, head, i_dirty) { 919 if (test_bit(NILFS_I_COLLECTED, &ii->i_state)) 920 clear_bit(NILFS_I_COLLECTED, &ii->i_state); 921 } 922 } 923 924 static void nilfs_drop_collected_inodes(struct list_head *head) 925 { 926 struct nilfs_inode_info *ii; 927 928 list_for_each_entry(ii, head, i_dirty) { 929 if (!test_and_clear_bit(NILFS_I_COLLECTED, &ii->i_state)) 930 continue; 931 932 clear_bit(NILFS_I_INODE_DIRTY, &ii->i_state); 933 set_bit(NILFS_I_UPDATED, &ii->i_state); 934 } 935 } 936 937 static int nilfs_segctor_apply_buffers(struct nilfs_sc_info *sci, 938 struct inode *inode, 939 struct list_head *listp, 940 int (*collect)(struct nilfs_sc_info *, 941 struct buffer_head *, 942 struct inode *)) 943 { 944 struct buffer_head *bh, *n; 945 int err = 0; 946 947 if (collect) { 948 list_for_each_entry_safe(bh, n, listp, b_assoc_buffers) { 949 list_del_init(&bh->b_assoc_buffers); 950 err = collect(sci, bh, inode); 951 brelse(bh); 952 if (unlikely(err)) 953 goto dispose_buffers; 954 } 955 return 0; 956 } 957 958 dispose_buffers: 959 while (!list_empty(listp)) { 960 bh = list_first_entry(listp, struct buffer_head, 961 b_assoc_buffers); 962 list_del_init(&bh->b_assoc_buffers); 963 brelse(bh); 964 } 965 return err; 966 } 967 968 static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci) 969 { 970 /* Remaining number of blocks within segment buffer */ 971 return sci->sc_segbuf_nblocks - 972 (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks); 973 } 974 975 static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci, 976 struct inode *inode, 977 struct nilfs_sc_operations *sc_ops) 978 { 979 LIST_HEAD(data_buffers); 980 LIST_HEAD(node_buffers); 981 int err; 982 983 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 984 size_t n, rest = nilfs_segctor_buffer_rest(sci); 985 986 n = nilfs_lookup_dirty_data_buffers( 987 inode, &data_buffers, rest + 1, 0, LLONG_MAX); 988 if (n > rest) { 989 err = nilfs_segctor_apply_buffers( 990 sci, inode, &data_buffers, 991 sc_ops->collect_data); 992 BUG_ON(!err); /* always receive -E2BIG or true error */ 993 goto break_or_fail; 994 } 995 } 996 nilfs_lookup_dirty_node_buffers(inode, &node_buffers); 997 998 if (!(sci->sc_stage.flags & NILFS_CF_NODE)) { 999 err = nilfs_segctor_apply_buffers( 1000 sci, inode, &data_buffers, sc_ops->collect_data); 1001 if (unlikely(err)) { 1002 /* dispose node list */ 1003 nilfs_segctor_apply_buffers( 1004 sci, inode, &node_buffers, NULL); 1005 goto break_or_fail; 1006 } 1007 sci->sc_stage.flags |= NILFS_CF_NODE; 1008 } 1009 /* Collect node */ 1010 err = nilfs_segctor_apply_buffers( 1011 sci, inode, &node_buffers, sc_ops->collect_node); 1012 if (unlikely(err)) 1013 goto break_or_fail; 1014 1015 nilfs_bmap_lookup_dirty_buffers(NILFS_I(inode)->i_bmap, &node_buffers); 1016 err = nilfs_segctor_apply_buffers( 1017 sci, inode, &node_buffers, sc_ops->collect_bmap); 1018 if (unlikely(err)) 1019 goto break_or_fail; 1020 1021 nilfs_segctor_end_finfo(sci, inode); 1022 sci->sc_stage.flags &= ~NILFS_CF_NODE; 1023 1024 break_or_fail: 1025 return err; 1026 } 1027 1028 static int nilfs_segctor_scan_file_dsync(struct nilfs_sc_info *sci, 1029 struct inode *inode) 1030 { 1031 LIST_HEAD(data_buffers); 1032 size_t n, rest = nilfs_segctor_buffer_rest(sci); 1033 int err; 1034 1035 n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1, 1036 sci->sc_dsync_start, 1037 sci->sc_dsync_end); 1038 1039 err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers, 1040 nilfs_collect_file_data); 1041 if (!err) { 1042 nilfs_segctor_end_finfo(sci, inode); 1043 BUG_ON(n > rest); 1044 /* always receive -E2BIG or true error if n > rest */ 1045 } 1046 return err; 1047 } 1048 1049 static int nilfs_segctor_collect_blocks(struct nilfs_sc_info *sci, int mode) 1050 { 1051 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1052 struct list_head *head; 1053 struct nilfs_inode_info *ii; 1054 size_t ndone; 1055 int err = 0; 1056 1057 switch (sci->sc_stage.scnt) { 1058 case NILFS_ST_INIT: 1059 /* Pre-processes */ 1060 sci->sc_stage.flags = 0; 1061 1062 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) { 1063 sci->sc_nblk_inc = 0; 1064 sci->sc_curseg->sb_sum.flags = NILFS_SS_LOGBGN; 1065 if (mode == SC_LSEG_DSYNC) { 1066 sci->sc_stage.scnt = NILFS_ST_DSYNC; 1067 goto dsync_mode; 1068 } 1069 } 1070 1071 sci->sc_stage.dirty_file_ptr = NULL; 1072 sci->sc_stage.gc_inode_ptr = NULL; 1073 if (mode == SC_FLUSH_DAT) { 1074 sci->sc_stage.scnt = NILFS_ST_DAT; 1075 goto dat_stage; 1076 } 1077 sci->sc_stage.scnt++; /* Fall through */ 1078 case NILFS_ST_GC: 1079 if (nilfs_doing_gc()) { 1080 head = &sci->sc_gc_inodes; 1081 ii = list_prepare_entry(sci->sc_stage.gc_inode_ptr, 1082 head, i_dirty); 1083 list_for_each_entry_continue(ii, head, i_dirty) { 1084 err = nilfs_segctor_scan_file( 1085 sci, &ii->vfs_inode, 1086 &nilfs_sc_file_ops); 1087 if (unlikely(err)) { 1088 sci->sc_stage.gc_inode_ptr = list_entry( 1089 ii->i_dirty.prev, 1090 struct nilfs_inode_info, 1091 i_dirty); 1092 goto break_or_fail; 1093 } 1094 set_bit(NILFS_I_COLLECTED, &ii->i_state); 1095 } 1096 sci->sc_stage.gc_inode_ptr = NULL; 1097 } 1098 sci->sc_stage.scnt++; /* Fall through */ 1099 case NILFS_ST_FILE: 1100 head = &sci->sc_dirty_files; 1101 ii = list_prepare_entry(sci->sc_stage.dirty_file_ptr, head, 1102 i_dirty); 1103 list_for_each_entry_continue(ii, head, i_dirty) { 1104 clear_bit(NILFS_I_DIRTY, &ii->i_state); 1105 1106 err = nilfs_segctor_scan_file(sci, &ii->vfs_inode, 1107 &nilfs_sc_file_ops); 1108 if (unlikely(err)) { 1109 sci->sc_stage.dirty_file_ptr = 1110 list_entry(ii->i_dirty.prev, 1111 struct nilfs_inode_info, 1112 i_dirty); 1113 goto break_or_fail; 1114 } 1115 /* sci->sc_stage.dirty_file_ptr = NILFS_I(inode); */ 1116 /* XXX: required ? */ 1117 } 1118 sci->sc_stage.dirty_file_ptr = NULL; 1119 if (mode == SC_FLUSH_FILE) { 1120 sci->sc_stage.scnt = NILFS_ST_DONE; 1121 return 0; 1122 } 1123 sci->sc_stage.scnt++; 1124 sci->sc_stage.flags |= NILFS_CF_IFILE_STARTED; 1125 /* Fall through */ 1126 case NILFS_ST_IFILE: 1127 err = nilfs_segctor_scan_file(sci, sci->sc_root->ifile, 1128 &nilfs_sc_file_ops); 1129 if (unlikely(err)) 1130 break; 1131 sci->sc_stage.scnt++; 1132 /* Creating a checkpoint */ 1133 err = nilfs_segctor_create_checkpoint(sci); 1134 if (unlikely(err)) 1135 break; 1136 /* Fall through */ 1137 case NILFS_ST_CPFILE: 1138 err = nilfs_segctor_scan_file(sci, nilfs->ns_cpfile, 1139 &nilfs_sc_file_ops); 1140 if (unlikely(err)) 1141 break; 1142 sci->sc_stage.scnt++; /* Fall through */ 1143 case NILFS_ST_SUFILE: 1144 err = nilfs_sufile_freev(nilfs->ns_sufile, sci->sc_freesegs, 1145 sci->sc_nfreesegs, &ndone); 1146 if (unlikely(err)) { 1147 nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1148 sci->sc_freesegs, ndone, 1149 NULL); 1150 break; 1151 } 1152 sci->sc_stage.flags |= NILFS_CF_SUFREED; 1153 1154 err = nilfs_segctor_scan_file(sci, nilfs->ns_sufile, 1155 &nilfs_sc_file_ops); 1156 if (unlikely(err)) 1157 break; 1158 sci->sc_stage.scnt++; /* Fall through */ 1159 case NILFS_ST_DAT: 1160 dat_stage: 1161 err = nilfs_segctor_scan_file(sci, nilfs->ns_dat, 1162 &nilfs_sc_dat_ops); 1163 if (unlikely(err)) 1164 break; 1165 if (mode == SC_FLUSH_DAT) { 1166 sci->sc_stage.scnt = NILFS_ST_DONE; 1167 return 0; 1168 } 1169 sci->sc_stage.scnt++; /* Fall through */ 1170 case NILFS_ST_SR: 1171 if (mode == SC_LSEG_SR) { 1172 /* Appending a super root */ 1173 err = nilfs_segctor_add_super_root(sci); 1174 if (unlikely(err)) 1175 break; 1176 } 1177 /* End of a logical segment */ 1178 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1179 sci->sc_stage.scnt = NILFS_ST_DONE; 1180 return 0; 1181 case NILFS_ST_DSYNC: 1182 dsync_mode: 1183 sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT; 1184 ii = sci->sc_dsync_inode; 1185 if (!test_bit(NILFS_I_BUSY, &ii->i_state)) 1186 break; 1187 1188 err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode); 1189 if (unlikely(err)) 1190 break; 1191 sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND; 1192 sci->sc_stage.scnt = NILFS_ST_DONE; 1193 return 0; 1194 case NILFS_ST_DONE: 1195 return 0; 1196 default: 1197 BUG(); 1198 } 1199 1200 break_or_fail: 1201 return err; 1202 } 1203 1204 /** 1205 * nilfs_segctor_begin_construction - setup segment buffer to make a new log 1206 * @sci: nilfs_sc_info 1207 * @nilfs: nilfs object 1208 */ 1209 static int nilfs_segctor_begin_construction(struct nilfs_sc_info *sci, 1210 struct the_nilfs *nilfs) 1211 { 1212 struct nilfs_segment_buffer *segbuf, *prev; 1213 __u64 nextnum; 1214 int err, alloc = 0; 1215 1216 segbuf = nilfs_segbuf_new(sci->sc_super); 1217 if (unlikely(!segbuf)) 1218 return -ENOMEM; 1219 1220 if (list_empty(&sci->sc_write_logs)) { 1221 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 1222 nilfs->ns_pseg_offset, nilfs); 1223 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1224 nilfs_shift_to_next_segment(nilfs); 1225 nilfs_segbuf_map(segbuf, nilfs->ns_segnum, 0, nilfs); 1226 } 1227 1228 segbuf->sb_sum.seg_seq = nilfs->ns_seg_seq; 1229 nextnum = nilfs->ns_nextnum; 1230 1231 if (nilfs->ns_segnum == nilfs->ns_nextnum) 1232 /* Start from the head of a new full segment */ 1233 alloc++; 1234 } else { 1235 /* Continue logs */ 1236 prev = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1237 nilfs_segbuf_map_cont(segbuf, prev); 1238 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq; 1239 nextnum = prev->sb_nextnum; 1240 1241 if (segbuf->sb_rest_blocks < NILFS_PSEG_MIN_BLOCKS) { 1242 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1243 segbuf->sb_sum.seg_seq++; 1244 alloc++; 1245 } 1246 } 1247 1248 err = nilfs_sufile_mark_dirty(nilfs->ns_sufile, segbuf->sb_segnum); 1249 if (err) 1250 goto failed; 1251 1252 if (alloc) { 1253 err = nilfs_sufile_alloc(nilfs->ns_sufile, &nextnum); 1254 if (err) 1255 goto failed; 1256 } 1257 nilfs_segbuf_set_next_segnum(segbuf, nextnum, nilfs); 1258 1259 BUG_ON(!list_empty(&sci->sc_segbufs)); 1260 list_add_tail(&segbuf->sb_list, &sci->sc_segbufs); 1261 sci->sc_segbuf_nblocks = segbuf->sb_rest_blocks; 1262 return 0; 1263 1264 failed: 1265 nilfs_segbuf_free(segbuf); 1266 return err; 1267 } 1268 1269 static int nilfs_segctor_extend_segments(struct nilfs_sc_info *sci, 1270 struct the_nilfs *nilfs, int nadd) 1271 { 1272 struct nilfs_segment_buffer *segbuf, *prev; 1273 struct inode *sufile = nilfs->ns_sufile; 1274 __u64 nextnextnum; 1275 LIST_HEAD(list); 1276 int err, ret, i; 1277 1278 prev = NILFS_LAST_SEGBUF(&sci->sc_segbufs); 1279 /* 1280 * Since the segment specified with nextnum might be allocated during 1281 * the previous construction, the buffer including its segusage may 1282 * not be dirty. The following call ensures that the buffer is dirty 1283 * and will pin the buffer on memory until the sufile is written. 1284 */ 1285 err = nilfs_sufile_mark_dirty(sufile, prev->sb_nextnum); 1286 if (unlikely(err)) 1287 return err; 1288 1289 for (i = 0; i < nadd; i++) { 1290 /* extend segment info */ 1291 err = -ENOMEM; 1292 segbuf = nilfs_segbuf_new(sci->sc_super); 1293 if (unlikely(!segbuf)) 1294 goto failed; 1295 1296 /* map this buffer to region of segment on-disk */ 1297 nilfs_segbuf_map(segbuf, prev->sb_nextnum, 0, nilfs); 1298 sci->sc_segbuf_nblocks += segbuf->sb_rest_blocks; 1299 1300 /* allocate the next next full segment */ 1301 err = nilfs_sufile_alloc(sufile, &nextnextnum); 1302 if (unlikely(err)) 1303 goto failed_segbuf; 1304 1305 segbuf->sb_sum.seg_seq = prev->sb_sum.seg_seq + 1; 1306 nilfs_segbuf_set_next_segnum(segbuf, nextnextnum, nilfs); 1307 1308 list_add_tail(&segbuf->sb_list, &list); 1309 prev = segbuf; 1310 } 1311 list_splice_tail(&list, &sci->sc_segbufs); 1312 return 0; 1313 1314 failed_segbuf: 1315 nilfs_segbuf_free(segbuf); 1316 failed: 1317 list_for_each_entry(segbuf, &list, sb_list) { 1318 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1319 WARN_ON(ret); /* never fails */ 1320 } 1321 nilfs_destroy_logs(&list); 1322 return err; 1323 } 1324 1325 static void nilfs_free_incomplete_logs(struct list_head *logs, 1326 struct the_nilfs *nilfs) 1327 { 1328 struct nilfs_segment_buffer *segbuf, *prev; 1329 struct inode *sufile = nilfs->ns_sufile; 1330 int ret; 1331 1332 segbuf = NILFS_FIRST_SEGBUF(logs); 1333 if (nilfs->ns_nextnum != segbuf->sb_nextnum) { 1334 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1335 WARN_ON(ret); /* never fails */ 1336 } 1337 if (atomic_read(&segbuf->sb_err)) { 1338 /* Case 1: The first segment failed */ 1339 if (segbuf->sb_pseg_start != segbuf->sb_fseg_start) 1340 /* Case 1a: Partial segment appended into an existing 1341 segment */ 1342 nilfs_terminate_segment(nilfs, segbuf->sb_fseg_start, 1343 segbuf->sb_fseg_end); 1344 else /* Case 1b: New full segment */ 1345 set_nilfs_discontinued(nilfs); 1346 } 1347 1348 prev = segbuf; 1349 list_for_each_entry_continue(segbuf, logs, sb_list) { 1350 if (prev->sb_nextnum != segbuf->sb_nextnum) { 1351 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1352 WARN_ON(ret); /* never fails */ 1353 } 1354 if (atomic_read(&segbuf->sb_err) && 1355 segbuf->sb_segnum != nilfs->ns_nextnum) 1356 /* Case 2: extended segment (!= next) failed */ 1357 nilfs_sufile_set_error(sufile, segbuf->sb_segnum); 1358 prev = segbuf; 1359 } 1360 } 1361 1362 static void nilfs_segctor_update_segusage(struct nilfs_sc_info *sci, 1363 struct inode *sufile) 1364 { 1365 struct nilfs_segment_buffer *segbuf; 1366 unsigned long live_blocks; 1367 int ret; 1368 1369 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1370 live_blocks = segbuf->sb_sum.nblocks + 1371 (segbuf->sb_pseg_start - segbuf->sb_fseg_start); 1372 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1373 live_blocks, 1374 sci->sc_seg_ctime); 1375 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1376 } 1377 } 1378 1379 static void nilfs_cancel_segusage(struct list_head *logs, struct inode *sufile) 1380 { 1381 struct nilfs_segment_buffer *segbuf; 1382 int ret; 1383 1384 segbuf = NILFS_FIRST_SEGBUF(logs); 1385 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1386 segbuf->sb_pseg_start - 1387 segbuf->sb_fseg_start, 0); 1388 WARN_ON(ret); /* always succeed because the segusage is dirty */ 1389 1390 list_for_each_entry_continue(segbuf, logs, sb_list) { 1391 ret = nilfs_sufile_set_segment_usage(sufile, segbuf->sb_segnum, 1392 0, 0); 1393 WARN_ON(ret); /* always succeed */ 1394 } 1395 } 1396 1397 static void nilfs_segctor_truncate_segments(struct nilfs_sc_info *sci, 1398 struct nilfs_segment_buffer *last, 1399 struct inode *sufile) 1400 { 1401 struct nilfs_segment_buffer *segbuf = last; 1402 int ret; 1403 1404 list_for_each_entry_continue(segbuf, &sci->sc_segbufs, sb_list) { 1405 sci->sc_segbuf_nblocks -= segbuf->sb_rest_blocks; 1406 ret = nilfs_sufile_free(sufile, segbuf->sb_nextnum); 1407 WARN_ON(ret); 1408 } 1409 nilfs_truncate_logs(&sci->sc_segbufs, last); 1410 } 1411 1412 1413 static int nilfs_segctor_collect(struct nilfs_sc_info *sci, 1414 struct the_nilfs *nilfs, int mode) 1415 { 1416 struct nilfs_cstage prev_stage = sci->sc_stage; 1417 int err, nadd = 1; 1418 1419 /* Collection retry loop */ 1420 for (;;) { 1421 sci->sc_nblk_this_inc = 0; 1422 sci->sc_curseg = NILFS_FIRST_SEGBUF(&sci->sc_segbufs); 1423 1424 err = nilfs_segctor_reset_segment_buffer(sci); 1425 if (unlikely(err)) 1426 goto failed; 1427 1428 err = nilfs_segctor_collect_blocks(sci, mode); 1429 sci->sc_nblk_this_inc += sci->sc_curseg->sb_sum.nblocks; 1430 if (!err) 1431 break; 1432 1433 if (unlikely(err != -E2BIG)) 1434 goto failed; 1435 1436 /* The current segment is filled up */ 1437 if (mode != SC_LSEG_SR || sci->sc_stage.scnt < NILFS_ST_CPFILE) 1438 break; 1439 1440 nilfs_clear_logs(&sci->sc_segbufs); 1441 1442 err = nilfs_segctor_extend_segments(sci, nilfs, nadd); 1443 if (unlikely(err)) 1444 return err; 1445 1446 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1447 err = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1448 sci->sc_freesegs, 1449 sci->sc_nfreesegs, 1450 NULL); 1451 WARN_ON(err); /* do not happen */ 1452 } 1453 nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA); 1454 sci->sc_stage = prev_stage; 1455 } 1456 nilfs_segctor_truncate_segments(sci, sci->sc_curseg, nilfs->ns_sufile); 1457 return 0; 1458 1459 failed: 1460 return err; 1461 } 1462 1463 static void nilfs_list_replace_buffer(struct buffer_head *old_bh, 1464 struct buffer_head *new_bh) 1465 { 1466 BUG_ON(!list_empty(&new_bh->b_assoc_buffers)); 1467 1468 list_replace_init(&old_bh->b_assoc_buffers, &new_bh->b_assoc_buffers); 1469 /* The caller must release old_bh */ 1470 } 1471 1472 static int 1473 nilfs_segctor_update_payload_blocknr(struct nilfs_sc_info *sci, 1474 struct nilfs_segment_buffer *segbuf, 1475 int mode) 1476 { 1477 struct inode *inode = NULL; 1478 sector_t blocknr; 1479 unsigned long nfinfo = segbuf->sb_sum.nfinfo; 1480 unsigned long nblocks = 0, ndatablk = 0; 1481 struct nilfs_sc_operations *sc_op = NULL; 1482 struct nilfs_segsum_pointer ssp; 1483 struct nilfs_finfo *finfo = NULL; 1484 union nilfs_binfo binfo; 1485 struct buffer_head *bh, *bh_org; 1486 ino_t ino = 0; 1487 int err = 0; 1488 1489 if (!nfinfo) 1490 goto out; 1491 1492 blocknr = segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk; 1493 ssp.bh = NILFS_SEGBUF_FIRST_BH(&segbuf->sb_segsum_buffers); 1494 ssp.offset = sizeof(struct nilfs_segment_summary); 1495 1496 list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { 1497 if (bh == segbuf->sb_super_root) 1498 break; 1499 if (!finfo) { 1500 finfo = nilfs_segctor_map_segsum_entry( 1501 sci, &ssp, sizeof(*finfo)); 1502 ino = le64_to_cpu(finfo->fi_ino); 1503 nblocks = le32_to_cpu(finfo->fi_nblocks); 1504 ndatablk = le32_to_cpu(finfo->fi_ndatablk); 1505 1506 inode = bh->b_page->mapping->host; 1507 1508 if (mode == SC_LSEG_DSYNC) 1509 sc_op = &nilfs_sc_dsync_ops; 1510 else if (ino == NILFS_DAT_INO) 1511 sc_op = &nilfs_sc_dat_ops; 1512 else /* file blocks */ 1513 sc_op = &nilfs_sc_file_ops; 1514 } 1515 bh_org = bh; 1516 get_bh(bh_org); 1517 err = nilfs_bmap_assign(NILFS_I(inode)->i_bmap, &bh, blocknr, 1518 &binfo); 1519 if (bh != bh_org) 1520 nilfs_list_replace_buffer(bh_org, bh); 1521 brelse(bh_org); 1522 if (unlikely(err)) 1523 goto failed_bmap; 1524 1525 if (ndatablk > 0) 1526 sc_op->write_data_binfo(sci, &ssp, &binfo); 1527 else 1528 sc_op->write_node_binfo(sci, &ssp, &binfo); 1529 1530 blocknr++; 1531 if (--nblocks == 0) { 1532 finfo = NULL; 1533 if (--nfinfo == 0) 1534 break; 1535 } else if (ndatablk > 0) 1536 ndatablk--; 1537 } 1538 out: 1539 return 0; 1540 1541 failed_bmap: 1542 return err; 1543 } 1544 1545 static int nilfs_segctor_assign(struct nilfs_sc_info *sci, int mode) 1546 { 1547 struct nilfs_segment_buffer *segbuf; 1548 int err; 1549 1550 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1551 err = nilfs_segctor_update_payload_blocknr(sci, segbuf, mode); 1552 if (unlikely(err)) 1553 return err; 1554 nilfs_segbuf_fill_in_segsum(segbuf); 1555 } 1556 return 0; 1557 } 1558 1559 static void nilfs_begin_page_io(struct page *page) 1560 { 1561 if (!page || PageWriteback(page)) 1562 /* For split b-tree node pages, this function may be called 1563 twice. We ignore the 2nd or later calls by this check. */ 1564 return; 1565 1566 lock_page(page); 1567 clear_page_dirty_for_io(page); 1568 set_page_writeback(page); 1569 unlock_page(page); 1570 } 1571 1572 static void nilfs_segctor_prepare_write(struct nilfs_sc_info *sci) 1573 { 1574 struct nilfs_segment_buffer *segbuf; 1575 struct page *bd_page = NULL, *fs_page = NULL; 1576 1577 list_for_each_entry(segbuf, &sci->sc_segbufs, sb_list) { 1578 struct buffer_head *bh; 1579 1580 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1581 b_assoc_buffers) { 1582 if (bh->b_page != bd_page) { 1583 if (bd_page) { 1584 lock_page(bd_page); 1585 clear_page_dirty_for_io(bd_page); 1586 set_page_writeback(bd_page); 1587 unlock_page(bd_page); 1588 } 1589 bd_page = bh->b_page; 1590 } 1591 } 1592 1593 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1594 b_assoc_buffers) { 1595 if (bh == segbuf->sb_super_root) { 1596 if (bh->b_page != bd_page) { 1597 lock_page(bd_page); 1598 clear_page_dirty_for_io(bd_page); 1599 set_page_writeback(bd_page); 1600 unlock_page(bd_page); 1601 bd_page = bh->b_page; 1602 } 1603 break; 1604 } 1605 if (bh->b_page != fs_page) { 1606 nilfs_begin_page_io(fs_page); 1607 fs_page = bh->b_page; 1608 } 1609 } 1610 } 1611 if (bd_page) { 1612 lock_page(bd_page); 1613 clear_page_dirty_for_io(bd_page); 1614 set_page_writeback(bd_page); 1615 unlock_page(bd_page); 1616 } 1617 nilfs_begin_page_io(fs_page); 1618 } 1619 1620 static int nilfs_segctor_write(struct nilfs_sc_info *sci, 1621 struct the_nilfs *nilfs) 1622 { 1623 int ret; 1624 1625 ret = nilfs_write_logs(&sci->sc_segbufs, nilfs); 1626 list_splice_tail_init(&sci->sc_segbufs, &sci->sc_write_logs); 1627 return ret; 1628 } 1629 1630 static void nilfs_end_page_io(struct page *page, int err) 1631 { 1632 if (!page) 1633 return; 1634 1635 if (buffer_nilfs_node(page_buffers(page)) && !PageWriteback(page)) { 1636 /* 1637 * For b-tree node pages, this function may be called twice 1638 * or more because they might be split in a segment. 1639 */ 1640 if (PageDirty(page)) { 1641 /* 1642 * For pages holding split b-tree node buffers, dirty 1643 * flag on the buffers may be cleared discretely. 1644 * In that case, the page is once redirtied for 1645 * remaining buffers, and it must be cancelled if 1646 * all the buffers get cleaned later. 1647 */ 1648 lock_page(page); 1649 if (nilfs_page_buffers_clean(page)) 1650 __nilfs_clear_page_dirty(page); 1651 unlock_page(page); 1652 } 1653 return; 1654 } 1655 1656 if (!err) { 1657 if (!nilfs_page_buffers_clean(page)) 1658 __set_page_dirty_nobuffers(page); 1659 ClearPageError(page); 1660 } else { 1661 __set_page_dirty_nobuffers(page); 1662 SetPageError(page); 1663 } 1664 1665 end_page_writeback(page); 1666 } 1667 1668 static void nilfs_abort_logs(struct list_head *logs, int err) 1669 { 1670 struct nilfs_segment_buffer *segbuf; 1671 struct page *bd_page = NULL, *fs_page = NULL; 1672 struct buffer_head *bh; 1673 1674 if (list_empty(logs)) 1675 return; 1676 1677 list_for_each_entry(segbuf, logs, sb_list) { 1678 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1679 b_assoc_buffers) { 1680 if (bh->b_page != bd_page) { 1681 if (bd_page) 1682 end_page_writeback(bd_page); 1683 bd_page = bh->b_page; 1684 } 1685 } 1686 1687 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1688 b_assoc_buffers) { 1689 if (bh == segbuf->sb_super_root) { 1690 if (bh->b_page != bd_page) { 1691 end_page_writeback(bd_page); 1692 bd_page = bh->b_page; 1693 } 1694 break; 1695 } 1696 if (bh->b_page != fs_page) { 1697 nilfs_end_page_io(fs_page, err); 1698 fs_page = bh->b_page; 1699 } 1700 } 1701 } 1702 if (bd_page) 1703 end_page_writeback(bd_page); 1704 1705 nilfs_end_page_io(fs_page, err); 1706 } 1707 1708 static void nilfs_segctor_abort_construction(struct nilfs_sc_info *sci, 1709 struct the_nilfs *nilfs, int err) 1710 { 1711 LIST_HEAD(logs); 1712 int ret; 1713 1714 list_splice_tail_init(&sci->sc_write_logs, &logs); 1715 ret = nilfs_wait_on_logs(&logs); 1716 nilfs_abort_logs(&logs, ret ? : err); 1717 1718 list_splice_tail_init(&sci->sc_segbufs, &logs); 1719 nilfs_cancel_segusage(&logs, nilfs->ns_sufile); 1720 nilfs_free_incomplete_logs(&logs, nilfs); 1721 1722 if (sci->sc_stage.flags & NILFS_CF_SUFREED) { 1723 ret = nilfs_sufile_cancel_freev(nilfs->ns_sufile, 1724 sci->sc_freesegs, 1725 sci->sc_nfreesegs, 1726 NULL); 1727 WARN_ON(ret); /* do not happen */ 1728 } 1729 1730 nilfs_destroy_logs(&logs); 1731 } 1732 1733 static void nilfs_set_next_segment(struct the_nilfs *nilfs, 1734 struct nilfs_segment_buffer *segbuf) 1735 { 1736 nilfs->ns_segnum = segbuf->sb_segnum; 1737 nilfs->ns_nextnum = segbuf->sb_nextnum; 1738 nilfs->ns_pseg_offset = segbuf->sb_pseg_start - segbuf->sb_fseg_start 1739 + segbuf->sb_sum.nblocks; 1740 nilfs->ns_seg_seq = segbuf->sb_sum.seg_seq; 1741 nilfs->ns_ctime = segbuf->sb_sum.ctime; 1742 } 1743 1744 static void nilfs_segctor_complete_write(struct nilfs_sc_info *sci) 1745 { 1746 struct nilfs_segment_buffer *segbuf; 1747 struct page *bd_page = NULL, *fs_page = NULL; 1748 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1749 int update_sr = false; 1750 1751 list_for_each_entry(segbuf, &sci->sc_write_logs, sb_list) { 1752 struct buffer_head *bh; 1753 1754 list_for_each_entry(bh, &segbuf->sb_segsum_buffers, 1755 b_assoc_buffers) { 1756 set_buffer_uptodate(bh); 1757 clear_buffer_dirty(bh); 1758 if (bh->b_page != bd_page) { 1759 if (bd_page) 1760 end_page_writeback(bd_page); 1761 bd_page = bh->b_page; 1762 } 1763 } 1764 /* 1765 * We assume that the buffers which belong to the same page 1766 * continue over the buffer list. 1767 * Under this assumption, the last BHs of pages is 1768 * identifiable by the discontinuity of bh->b_page 1769 * (page != fs_page). 1770 * 1771 * For B-tree node blocks, however, this assumption is not 1772 * guaranteed. The cleanup code of B-tree node pages needs 1773 * special care. 1774 */ 1775 list_for_each_entry(bh, &segbuf->sb_payload_buffers, 1776 b_assoc_buffers) { 1777 set_buffer_uptodate(bh); 1778 clear_buffer_dirty(bh); 1779 clear_buffer_delay(bh); 1780 clear_buffer_nilfs_volatile(bh); 1781 clear_buffer_nilfs_redirected(bh); 1782 if (bh == segbuf->sb_super_root) { 1783 if (bh->b_page != bd_page) { 1784 end_page_writeback(bd_page); 1785 bd_page = bh->b_page; 1786 } 1787 update_sr = true; 1788 break; 1789 } 1790 if (bh->b_page != fs_page) { 1791 nilfs_end_page_io(fs_page, 0); 1792 fs_page = bh->b_page; 1793 } 1794 } 1795 1796 if (!nilfs_segbuf_simplex(segbuf)) { 1797 if (segbuf->sb_sum.flags & NILFS_SS_LOGBGN) { 1798 set_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1799 sci->sc_lseg_stime = jiffies; 1800 } 1801 if (segbuf->sb_sum.flags & NILFS_SS_LOGEND) 1802 clear_bit(NILFS_SC_UNCLOSED, &sci->sc_flags); 1803 } 1804 } 1805 /* 1806 * Since pages may continue over multiple segment buffers, 1807 * end of the last page must be checked outside of the loop. 1808 */ 1809 if (bd_page) 1810 end_page_writeback(bd_page); 1811 1812 nilfs_end_page_io(fs_page, 0); 1813 1814 nilfs_drop_collected_inodes(&sci->sc_dirty_files); 1815 1816 if (nilfs_doing_gc()) 1817 nilfs_drop_collected_inodes(&sci->sc_gc_inodes); 1818 else 1819 nilfs->ns_nongc_ctime = sci->sc_seg_ctime; 1820 1821 sci->sc_nblk_inc += sci->sc_nblk_this_inc; 1822 1823 segbuf = NILFS_LAST_SEGBUF(&sci->sc_write_logs); 1824 nilfs_set_next_segment(nilfs, segbuf); 1825 1826 if (update_sr) { 1827 nilfs_set_last_segment(nilfs, segbuf->sb_pseg_start, 1828 segbuf->sb_sum.seg_seq, nilfs->ns_cno++); 1829 1830 clear_bit(NILFS_SC_HAVE_DELTA, &sci->sc_flags); 1831 clear_bit(NILFS_SC_DIRTY, &sci->sc_flags); 1832 set_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1833 nilfs_segctor_clear_metadata_dirty(sci); 1834 } else 1835 clear_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags); 1836 } 1837 1838 static int nilfs_segctor_wait(struct nilfs_sc_info *sci) 1839 { 1840 int ret; 1841 1842 ret = nilfs_wait_on_logs(&sci->sc_write_logs); 1843 if (!ret) { 1844 nilfs_segctor_complete_write(sci); 1845 nilfs_destroy_logs(&sci->sc_write_logs); 1846 } 1847 return ret; 1848 } 1849 1850 static int nilfs_segctor_collect_dirty_files(struct nilfs_sc_info *sci, 1851 struct the_nilfs *nilfs) 1852 { 1853 struct nilfs_inode_info *ii, *n; 1854 struct inode *ifile = sci->sc_root->ifile; 1855 1856 spin_lock(&nilfs->ns_inode_lock); 1857 retry: 1858 list_for_each_entry_safe(ii, n, &nilfs->ns_dirty_files, i_dirty) { 1859 if (!ii->i_bh) { 1860 struct buffer_head *ibh; 1861 int err; 1862 1863 spin_unlock(&nilfs->ns_inode_lock); 1864 err = nilfs_ifile_get_inode_block( 1865 ifile, ii->vfs_inode.i_ino, &ibh); 1866 if (unlikely(err)) { 1867 nilfs_warning(sci->sc_super, __func__, 1868 "failed to get inode block.\n"); 1869 return err; 1870 } 1871 mark_buffer_dirty(ibh); 1872 nilfs_mdt_mark_dirty(ifile); 1873 spin_lock(&nilfs->ns_inode_lock); 1874 if (likely(!ii->i_bh)) 1875 ii->i_bh = ibh; 1876 else 1877 brelse(ibh); 1878 goto retry; 1879 } 1880 1881 clear_bit(NILFS_I_QUEUED, &ii->i_state); 1882 set_bit(NILFS_I_BUSY, &ii->i_state); 1883 list_move_tail(&ii->i_dirty, &sci->sc_dirty_files); 1884 } 1885 spin_unlock(&nilfs->ns_inode_lock); 1886 1887 return 0; 1888 } 1889 1890 static void nilfs_segctor_drop_written_files(struct nilfs_sc_info *sci, 1891 struct the_nilfs *nilfs) 1892 { 1893 struct nilfs_transaction_info *ti = current->journal_info; 1894 struct nilfs_inode_info *ii, *n; 1895 1896 spin_lock(&nilfs->ns_inode_lock); 1897 list_for_each_entry_safe(ii, n, &sci->sc_dirty_files, i_dirty) { 1898 if (!test_and_clear_bit(NILFS_I_UPDATED, &ii->i_state) || 1899 test_bit(NILFS_I_DIRTY, &ii->i_state)) 1900 continue; 1901 1902 clear_bit(NILFS_I_BUSY, &ii->i_state); 1903 brelse(ii->i_bh); 1904 ii->i_bh = NULL; 1905 list_move_tail(&ii->i_dirty, &ti->ti_garbage); 1906 } 1907 spin_unlock(&nilfs->ns_inode_lock); 1908 } 1909 1910 /* 1911 * Main procedure of segment constructor 1912 */ 1913 static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) 1914 { 1915 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 1916 int err; 1917 1918 sci->sc_stage.scnt = NILFS_ST_INIT; 1919 sci->sc_cno = nilfs->ns_cno; 1920 1921 err = nilfs_segctor_collect_dirty_files(sci, nilfs); 1922 if (unlikely(err)) 1923 goto out; 1924 1925 if (nilfs_test_metadata_dirty(nilfs, sci->sc_root)) 1926 set_bit(NILFS_SC_DIRTY, &sci->sc_flags); 1927 1928 if (nilfs_segctor_clean(sci)) 1929 goto out; 1930 1931 do { 1932 sci->sc_stage.flags &= ~NILFS_CF_HISTORY_MASK; 1933 1934 err = nilfs_segctor_begin_construction(sci, nilfs); 1935 if (unlikely(err)) 1936 goto out; 1937 1938 /* Update time stamp */ 1939 sci->sc_seg_ctime = get_seconds(); 1940 1941 err = nilfs_segctor_collect(sci, nilfs, mode); 1942 if (unlikely(err)) 1943 goto failed; 1944 1945 /* Avoid empty segment */ 1946 if (sci->sc_stage.scnt == NILFS_ST_DONE && 1947 nilfs_segbuf_empty(sci->sc_curseg)) { 1948 nilfs_segctor_abort_construction(sci, nilfs, 1); 1949 goto out; 1950 } 1951 1952 err = nilfs_segctor_assign(sci, mode); 1953 if (unlikely(err)) 1954 goto failed; 1955 1956 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 1957 nilfs_segctor_fill_in_file_bmap(sci); 1958 1959 if (mode == SC_LSEG_SR && 1960 sci->sc_stage.scnt >= NILFS_ST_CPFILE) { 1961 err = nilfs_segctor_fill_in_checkpoint(sci); 1962 if (unlikely(err)) 1963 goto failed_to_write; 1964 1965 nilfs_segctor_fill_in_super_root(sci, nilfs); 1966 } 1967 nilfs_segctor_update_segusage(sci, nilfs->ns_sufile); 1968 1969 /* Write partial segments */ 1970 nilfs_segctor_prepare_write(sci); 1971 1972 nilfs_add_checksums_on_logs(&sci->sc_segbufs, 1973 nilfs->ns_crc_seed); 1974 1975 err = nilfs_segctor_write(sci, nilfs); 1976 if (unlikely(err)) 1977 goto failed_to_write; 1978 1979 if (sci->sc_stage.scnt == NILFS_ST_DONE || 1980 nilfs->ns_blocksize_bits != PAGE_CACHE_SHIFT) { 1981 /* 1982 * At this point, we avoid double buffering 1983 * for blocksize < pagesize because page dirty 1984 * flag is turned off during write and dirty 1985 * buffers are not properly collected for 1986 * pages crossing over segments. 1987 */ 1988 err = nilfs_segctor_wait(sci); 1989 if (err) 1990 goto failed_to_write; 1991 } 1992 } while (sci->sc_stage.scnt != NILFS_ST_DONE); 1993 1994 out: 1995 nilfs_segctor_drop_written_files(sci, nilfs); 1996 return err; 1997 1998 failed_to_write: 1999 if (sci->sc_stage.flags & NILFS_CF_IFILE_STARTED) 2000 nilfs_redirty_inodes(&sci->sc_dirty_files); 2001 2002 failed: 2003 if (nilfs_doing_gc()) 2004 nilfs_redirty_inodes(&sci->sc_gc_inodes); 2005 nilfs_segctor_abort_construction(sci, nilfs, err); 2006 goto out; 2007 } 2008 2009 /** 2010 * nilfs_segctor_start_timer - set timer of background write 2011 * @sci: nilfs_sc_info 2012 * 2013 * If the timer has already been set, it ignores the new request. 2014 * This function MUST be called within a section locking the segment 2015 * semaphore. 2016 */ 2017 static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) 2018 { 2019 spin_lock(&sci->sc_state_lock); 2020 if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { 2021 sci->sc_timer.expires = jiffies + sci->sc_interval; 2022 add_timer(&sci->sc_timer); 2023 sci->sc_state |= NILFS_SEGCTOR_COMMIT; 2024 } 2025 spin_unlock(&sci->sc_state_lock); 2026 } 2027 2028 static void nilfs_segctor_do_flush(struct nilfs_sc_info *sci, int bn) 2029 { 2030 spin_lock(&sci->sc_state_lock); 2031 if (!(sci->sc_flush_request & (1 << bn))) { 2032 unsigned long prev_req = sci->sc_flush_request; 2033 2034 sci->sc_flush_request |= (1 << bn); 2035 if (!prev_req) 2036 wake_up(&sci->sc_wait_daemon); 2037 } 2038 spin_unlock(&sci->sc_state_lock); 2039 } 2040 2041 /** 2042 * nilfs_flush_segment - trigger a segment construction for resource control 2043 * @sb: super block 2044 * @ino: inode number of the file to be flushed out. 2045 */ 2046 void nilfs_flush_segment(struct super_block *sb, ino_t ino) 2047 { 2048 struct the_nilfs *nilfs = sb->s_fs_info; 2049 struct nilfs_sc_info *sci = nilfs->ns_writer; 2050 2051 if (!sci || nilfs_doing_construction()) 2052 return; 2053 nilfs_segctor_do_flush(sci, NILFS_MDT_INODE(sb, ino) ? ino : 0); 2054 /* assign bit 0 to data files */ 2055 } 2056 2057 struct nilfs_segctor_wait_request { 2058 wait_queue_t wq; 2059 __u32 seq; 2060 int err; 2061 atomic_t done; 2062 }; 2063 2064 static int nilfs_segctor_sync(struct nilfs_sc_info *sci) 2065 { 2066 struct nilfs_segctor_wait_request wait_req; 2067 int err = 0; 2068 2069 spin_lock(&sci->sc_state_lock); 2070 init_wait(&wait_req.wq); 2071 wait_req.err = 0; 2072 atomic_set(&wait_req.done, 0); 2073 wait_req.seq = ++sci->sc_seq_request; 2074 spin_unlock(&sci->sc_state_lock); 2075 2076 init_waitqueue_entry(&wait_req.wq, current); 2077 add_wait_queue(&sci->sc_wait_request, &wait_req.wq); 2078 set_current_state(TASK_INTERRUPTIBLE); 2079 wake_up(&sci->sc_wait_daemon); 2080 2081 for (;;) { 2082 if (atomic_read(&wait_req.done)) { 2083 err = wait_req.err; 2084 break; 2085 } 2086 if (!signal_pending(current)) { 2087 schedule(); 2088 continue; 2089 } 2090 err = -ERESTARTSYS; 2091 break; 2092 } 2093 finish_wait(&sci->sc_wait_request, &wait_req.wq); 2094 return err; 2095 } 2096 2097 static void nilfs_segctor_wakeup(struct nilfs_sc_info *sci, int err) 2098 { 2099 struct nilfs_segctor_wait_request *wrq, *n; 2100 unsigned long flags; 2101 2102 spin_lock_irqsave(&sci->sc_wait_request.lock, flags); 2103 list_for_each_entry_safe(wrq, n, &sci->sc_wait_request.task_list, 2104 wq.task_list) { 2105 if (!atomic_read(&wrq->done) && 2106 nilfs_cnt32_ge(sci->sc_seq_done, wrq->seq)) { 2107 wrq->err = err; 2108 atomic_set(&wrq->done, 1); 2109 } 2110 if (atomic_read(&wrq->done)) { 2111 wrq->wq.func(&wrq->wq, 2112 TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 2113 0, NULL); 2114 } 2115 } 2116 spin_unlock_irqrestore(&sci->sc_wait_request.lock, flags); 2117 } 2118 2119 /** 2120 * nilfs_construct_segment - construct a logical segment 2121 * @sb: super block 2122 * 2123 * Return Value: On success, 0 is retured. On errors, one of the following 2124 * negative error code is returned. 2125 * 2126 * %-EROFS - Read only filesystem. 2127 * 2128 * %-EIO - I/O error 2129 * 2130 * %-ENOSPC - No space left on device (only in a panic state). 2131 * 2132 * %-ERESTARTSYS - Interrupted. 2133 * 2134 * %-ENOMEM - Insufficient memory available. 2135 */ 2136 int nilfs_construct_segment(struct super_block *sb) 2137 { 2138 struct the_nilfs *nilfs = sb->s_fs_info; 2139 struct nilfs_sc_info *sci = nilfs->ns_writer; 2140 struct nilfs_transaction_info *ti; 2141 int err; 2142 2143 if (!sci) 2144 return -EROFS; 2145 2146 /* A call inside transactions causes a deadlock. */ 2147 BUG_ON((ti = current->journal_info) && ti->ti_magic == NILFS_TI_MAGIC); 2148 2149 err = nilfs_segctor_sync(sci); 2150 return err; 2151 } 2152 2153 /** 2154 * nilfs_construct_dsync_segment - construct a data-only logical segment 2155 * @sb: super block 2156 * @inode: inode whose data blocks should be written out 2157 * @start: start byte offset 2158 * @end: end byte offset (inclusive) 2159 * 2160 * Return Value: On success, 0 is retured. On errors, one of the following 2161 * negative error code is returned. 2162 * 2163 * %-EROFS - Read only filesystem. 2164 * 2165 * %-EIO - I/O error 2166 * 2167 * %-ENOSPC - No space left on device (only in a panic state). 2168 * 2169 * %-ERESTARTSYS - Interrupted. 2170 * 2171 * %-ENOMEM - Insufficient memory available. 2172 */ 2173 int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode, 2174 loff_t start, loff_t end) 2175 { 2176 struct the_nilfs *nilfs = sb->s_fs_info; 2177 struct nilfs_sc_info *sci = nilfs->ns_writer; 2178 struct nilfs_inode_info *ii; 2179 struct nilfs_transaction_info ti; 2180 int err = 0; 2181 2182 if (!sci) 2183 return -EROFS; 2184 2185 nilfs_transaction_lock(sb, &ti, 0); 2186 2187 ii = NILFS_I(inode); 2188 if (test_bit(NILFS_I_INODE_DIRTY, &ii->i_state) || 2189 nilfs_test_opt(nilfs, STRICT_ORDER) || 2190 test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2191 nilfs_discontinued(nilfs)) { 2192 nilfs_transaction_unlock(sb); 2193 err = nilfs_segctor_sync(sci); 2194 return err; 2195 } 2196 2197 spin_lock(&nilfs->ns_inode_lock); 2198 if (!test_bit(NILFS_I_QUEUED, &ii->i_state) && 2199 !test_bit(NILFS_I_BUSY, &ii->i_state)) { 2200 spin_unlock(&nilfs->ns_inode_lock); 2201 nilfs_transaction_unlock(sb); 2202 return 0; 2203 } 2204 spin_unlock(&nilfs->ns_inode_lock); 2205 sci->sc_dsync_inode = ii; 2206 sci->sc_dsync_start = start; 2207 sci->sc_dsync_end = end; 2208 2209 err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC); 2210 2211 nilfs_transaction_unlock(sb); 2212 return err; 2213 } 2214 2215 #define FLUSH_FILE_BIT (0x1) /* data file only */ 2216 #define FLUSH_DAT_BIT (1 << NILFS_DAT_INO) /* DAT only */ 2217 2218 /** 2219 * nilfs_segctor_accept - record accepted sequence count of log-write requests 2220 * @sci: segment constructor object 2221 */ 2222 static void nilfs_segctor_accept(struct nilfs_sc_info *sci) 2223 { 2224 spin_lock(&sci->sc_state_lock); 2225 sci->sc_seq_accepted = sci->sc_seq_request; 2226 spin_unlock(&sci->sc_state_lock); 2227 del_timer_sync(&sci->sc_timer); 2228 } 2229 2230 /** 2231 * nilfs_segctor_notify - notify the result of request to caller threads 2232 * @sci: segment constructor object 2233 * @mode: mode of log forming 2234 * @err: error code to be notified 2235 */ 2236 static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) 2237 { 2238 /* Clear requests (even when the construction failed) */ 2239 spin_lock(&sci->sc_state_lock); 2240 2241 if (mode == SC_LSEG_SR) { 2242 sci->sc_state &= ~NILFS_SEGCTOR_COMMIT; 2243 sci->sc_seq_done = sci->sc_seq_accepted; 2244 nilfs_segctor_wakeup(sci, err); 2245 sci->sc_flush_request = 0; 2246 } else { 2247 if (mode == SC_FLUSH_FILE) 2248 sci->sc_flush_request &= ~FLUSH_FILE_BIT; 2249 else if (mode == SC_FLUSH_DAT) 2250 sci->sc_flush_request &= ~FLUSH_DAT_BIT; 2251 2252 /* re-enable timer if checkpoint creation was not done */ 2253 if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2254 time_before(jiffies, sci->sc_timer.expires)) 2255 add_timer(&sci->sc_timer); 2256 } 2257 spin_unlock(&sci->sc_state_lock); 2258 } 2259 2260 /** 2261 * nilfs_segctor_construct - form logs and write them to disk 2262 * @sci: segment constructor object 2263 * @mode: mode of log forming 2264 */ 2265 static int nilfs_segctor_construct(struct nilfs_sc_info *sci, int mode) 2266 { 2267 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2268 struct nilfs_super_block **sbp; 2269 int err = 0; 2270 2271 nilfs_segctor_accept(sci); 2272 2273 if (nilfs_discontinued(nilfs)) 2274 mode = SC_LSEG_SR; 2275 if (!nilfs_segctor_confirm(sci)) 2276 err = nilfs_segctor_do_construct(sci, mode); 2277 2278 if (likely(!err)) { 2279 if (mode != SC_FLUSH_DAT) 2280 atomic_set(&nilfs->ns_ndirtyblks, 0); 2281 if (test_bit(NILFS_SC_SUPER_ROOT, &sci->sc_flags) && 2282 nilfs_discontinued(nilfs)) { 2283 down_write(&nilfs->ns_sem); 2284 err = -EIO; 2285 sbp = nilfs_prepare_super(sci->sc_super, 2286 nilfs_sb_will_flip(nilfs)); 2287 if (likely(sbp)) { 2288 nilfs_set_log_cursor(sbp[0], nilfs); 2289 err = nilfs_commit_super(sci->sc_super, 2290 NILFS_SB_COMMIT); 2291 } 2292 up_write(&nilfs->ns_sem); 2293 } 2294 } 2295 2296 nilfs_segctor_notify(sci, mode, err); 2297 return err; 2298 } 2299 2300 static void nilfs_construction_timeout(unsigned long data) 2301 { 2302 struct task_struct *p = (struct task_struct *)data; 2303 wake_up_process(p); 2304 } 2305 2306 static void 2307 nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head) 2308 { 2309 struct nilfs_inode_info *ii, *n; 2310 2311 list_for_each_entry_safe(ii, n, head, i_dirty) { 2312 if (!test_bit(NILFS_I_UPDATED, &ii->i_state)) 2313 continue; 2314 list_del_init(&ii->i_dirty); 2315 truncate_inode_pages(&ii->vfs_inode.i_data, 0); 2316 nilfs_btnode_cache_clear(&ii->i_btnode_cache); 2317 iput(&ii->vfs_inode); 2318 } 2319 } 2320 2321 int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, 2322 void **kbufs) 2323 { 2324 struct the_nilfs *nilfs = sb->s_fs_info; 2325 struct nilfs_sc_info *sci = nilfs->ns_writer; 2326 struct nilfs_transaction_info ti; 2327 int err; 2328 2329 if (unlikely(!sci)) 2330 return -EROFS; 2331 2332 nilfs_transaction_lock(sb, &ti, 1); 2333 2334 err = nilfs_mdt_save_to_shadow_map(nilfs->ns_dat); 2335 if (unlikely(err)) 2336 goto out_unlock; 2337 2338 err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs); 2339 if (unlikely(err)) { 2340 nilfs_mdt_restore_from_shadow_map(nilfs->ns_dat); 2341 goto out_unlock; 2342 } 2343 2344 sci->sc_freesegs = kbufs[4]; 2345 sci->sc_nfreesegs = argv[4].v_nmembs; 2346 list_splice_tail_init(&nilfs->ns_gc_inodes, &sci->sc_gc_inodes); 2347 2348 for (;;) { 2349 err = nilfs_segctor_construct(sci, SC_LSEG_SR); 2350 nilfs_remove_written_gcinodes(nilfs, &sci->sc_gc_inodes); 2351 2352 if (likely(!err)) 2353 break; 2354 2355 nilfs_warning(sb, __func__, 2356 "segment construction failed. (err=%d)", err); 2357 set_current_state(TASK_INTERRUPTIBLE); 2358 schedule_timeout(sci->sc_interval); 2359 } 2360 if (nilfs_test_opt(nilfs, DISCARD)) { 2361 int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, 2362 sci->sc_nfreesegs); 2363 if (ret) { 2364 printk(KERN_WARNING 2365 "NILFS warning: error %d on discard request, " 2366 "turning discards off for the device\n", ret); 2367 nilfs_clear_opt(nilfs, DISCARD); 2368 } 2369 } 2370 2371 out_unlock: 2372 sci->sc_freesegs = NULL; 2373 sci->sc_nfreesegs = 0; 2374 nilfs_mdt_clear_shadow_map(nilfs->ns_dat); 2375 nilfs_transaction_unlock(sb); 2376 return err; 2377 } 2378 2379 static void nilfs_segctor_thread_construct(struct nilfs_sc_info *sci, int mode) 2380 { 2381 struct nilfs_transaction_info ti; 2382 2383 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2384 nilfs_segctor_construct(sci, mode); 2385 2386 /* 2387 * Unclosed segment should be retried. We do this using sc_timer. 2388 * Timeout of sc_timer will invoke complete construction which leads 2389 * to close the current logical segment. 2390 */ 2391 if (test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags)) 2392 nilfs_segctor_start_timer(sci); 2393 2394 nilfs_transaction_unlock(sci->sc_super); 2395 } 2396 2397 static void nilfs_segctor_do_immediate_flush(struct nilfs_sc_info *sci) 2398 { 2399 int mode = 0; 2400 int err; 2401 2402 spin_lock(&sci->sc_state_lock); 2403 mode = (sci->sc_flush_request & FLUSH_DAT_BIT) ? 2404 SC_FLUSH_DAT : SC_FLUSH_FILE; 2405 spin_unlock(&sci->sc_state_lock); 2406 2407 if (mode) { 2408 err = nilfs_segctor_do_construct(sci, mode); 2409 2410 spin_lock(&sci->sc_state_lock); 2411 sci->sc_flush_request &= (mode == SC_FLUSH_FILE) ? 2412 ~FLUSH_FILE_BIT : ~FLUSH_DAT_BIT; 2413 spin_unlock(&sci->sc_state_lock); 2414 } 2415 clear_bit(NILFS_SC_PRIOR_FLUSH, &sci->sc_flags); 2416 } 2417 2418 static int nilfs_segctor_flush_mode(struct nilfs_sc_info *sci) 2419 { 2420 if (!test_bit(NILFS_SC_UNCLOSED, &sci->sc_flags) || 2421 time_before(jiffies, sci->sc_lseg_stime + sci->sc_mjcp_freq)) { 2422 if (!(sci->sc_flush_request & ~FLUSH_FILE_BIT)) 2423 return SC_FLUSH_FILE; 2424 else if (!(sci->sc_flush_request & ~FLUSH_DAT_BIT)) 2425 return SC_FLUSH_DAT; 2426 } 2427 return SC_LSEG_SR; 2428 } 2429 2430 /** 2431 * nilfs_segctor_thread - main loop of the segment constructor thread. 2432 * @arg: pointer to a struct nilfs_sc_info. 2433 * 2434 * nilfs_segctor_thread() initializes a timer and serves as a daemon 2435 * to execute segment constructions. 2436 */ 2437 static int nilfs_segctor_thread(void *arg) 2438 { 2439 struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; 2440 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2441 int timeout = 0; 2442 2443 sci->sc_timer.data = (unsigned long)current; 2444 sci->sc_timer.function = nilfs_construction_timeout; 2445 2446 /* start sync. */ 2447 sci->sc_task = current; 2448 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_start_thread() */ 2449 printk(KERN_INFO 2450 "segctord starting. Construction interval = %lu seconds, " 2451 "CP frequency < %lu seconds\n", 2452 sci->sc_interval / HZ, sci->sc_mjcp_freq / HZ); 2453 2454 spin_lock(&sci->sc_state_lock); 2455 loop: 2456 for (;;) { 2457 int mode; 2458 2459 if (sci->sc_state & NILFS_SEGCTOR_QUIT) 2460 goto end_thread; 2461 2462 if (timeout || sci->sc_seq_request != sci->sc_seq_done) 2463 mode = SC_LSEG_SR; 2464 else if (!sci->sc_flush_request) 2465 break; 2466 else 2467 mode = nilfs_segctor_flush_mode(sci); 2468 2469 spin_unlock(&sci->sc_state_lock); 2470 nilfs_segctor_thread_construct(sci, mode); 2471 spin_lock(&sci->sc_state_lock); 2472 timeout = 0; 2473 } 2474 2475 2476 if (freezing(current)) { 2477 spin_unlock(&sci->sc_state_lock); 2478 try_to_freeze(); 2479 spin_lock(&sci->sc_state_lock); 2480 } else { 2481 DEFINE_WAIT(wait); 2482 int should_sleep = 1; 2483 2484 prepare_to_wait(&sci->sc_wait_daemon, &wait, 2485 TASK_INTERRUPTIBLE); 2486 2487 if (sci->sc_seq_request != sci->sc_seq_done) 2488 should_sleep = 0; 2489 else if (sci->sc_flush_request) 2490 should_sleep = 0; 2491 else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) 2492 should_sleep = time_before(jiffies, 2493 sci->sc_timer.expires); 2494 2495 if (should_sleep) { 2496 spin_unlock(&sci->sc_state_lock); 2497 schedule(); 2498 spin_lock(&sci->sc_state_lock); 2499 } 2500 finish_wait(&sci->sc_wait_daemon, &wait); 2501 timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && 2502 time_after_eq(jiffies, sci->sc_timer.expires)); 2503 2504 if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) 2505 set_nilfs_discontinued(nilfs); 2506 } 2507 goto loop; 2508 2509 end_thread: 2510 spin_unlock(&sci->sc_state_lock); 2511 2512 /* end sync. */ 2513 sci->sc_task = NULL; 2514 wake_up(&sci->sc_wait_task); /* for nilfs_segctor_kill_thread() */ 2515 return 0; 2516 } 2517 2518 static int nilfs_segctor_start_thread(struct nilfs_sc_info *sci) 2519 { 2520 struct task_struct *t; 2521 2522 t = kthread_run(nilfs_segctor_thread, sci, "segctord"); 2523 if (IS_ERR(t)) { 2524 int err = PTR_ERR(t); 2525 2526 printk(KERN_ERR "NILFS: error %d creating segctord thread\n", 2527 err); 2528 return err; 2529 } 2530 wait_event(sci->sc_wait_task, sci->sc_task != NULL); 2531 return 0; 2532 } 2533 2534 static void nilfs_segctor_kill_thread(struct nilfs_sc_info *sci) 2535 __acquires(&sci->sc_state_lock) 2536 __releases(&sci->sc_state_lock) 2537 { 2538 sci->sc_state |= NILFS_SEGCTOR_QUIT; 2539 2540 while (sci->sc_task) { 2541 wake_up(&sci->sc_wait_daemon); 2542 spin_unlock(&sci->sc_state_lock); 2543 wait_event(sci->sc_wait_task, sci->sc_task == NULL); 2544 spin_lock(&sci->sc_state_lock); 2545 } 2546 } 2547 2548 /* 2549 * Setup & clean-up functions 2550 */ 2551 static struct nilfs_sc_info *nilfs_segctor_new(struct super_block *sb, 2552 struct nilfs_root *root) 2553 { 2554 struct the_nilfs *nilfs = sb->s_fs_info; 2555 struct nilfs_sc_info *sci; 2556 2557 sci = kzalloc(sizeof(*sci), GFP_KERNEL); 2558 if (!sci) 2559 return NULL; 2560 2561 sci->sc_super = sb; 2562 2563 nilfs_get_root(root); 2564 sci->sc_root = root; 2565 2566 init_waitqueue_head(&sci->sc_wait_request); 2567 init_waitqueue_head(&sci->sc_wait_daemon); 2568 init_waitqueue_head(&sci->sc_wait_task); 2569 spin_lock_init(&sci->sc_state_lock); 2570 INIT_LIST_HEAD(&sci->sc_dirty_files); 2571 INIT_LIST_HEAD(&sci->sc_segbufs); 2572 INIT_LIST_HEAD(&sci->sc_write_logs); 2573 INIT_LIST_HEAD(&sci->sc_gc_inodes); 2574 init_timer(&sci->sc_timer); 2575 2576 sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; 2577 sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; 2578 sci->sc_watermark = NILFS_SC_DEFAULT_WATERMARK; 2579 2580 if (nilfs->ns_interval) 2581 sci->sc_interval = HZ * nilfs->ns_interval; 2582 if (nilfs->ns_watermark) 2583 sci->sc_watermark = nilfs->ns_watermark; 2584 return sci; 2585 } 2586 2587 static void nilfs_segctor_write_out(struct nilfs_sc_info *sci) 2588 { 2589 int ret, retrycount = NILFS_SC_CLEANUP_RETRY; 2590 2591 /* The segctord thread was stopped and its timer was removed. 2592 But some tasks remain. */ 2593 do { 2594 struct nilfs_transaction_info ti; 2595 2596 nilfs_transaction_lock(sci->sc_super, &ti, 0); 2597 ret = nilfs_segctor_construct(sci, SC_LSEG_SR); 2598 nilfs_transaction_unlock(sci->sc_super); 2599 2600 } while (ret && retrycount-- > 0); 2601 } 2602 2603 /** 2604 * nilfs_segctor_destroy - destroy the segment constructor. 2605 * @sci: nilfs_sc_info 2606 * 2607 * nilfs_segctor_destroy() kills the segctord thread and frees 2608 * the nilfs_sc_info struct. 2609 * Caller must hold the segment semaphore. 2610 */ 2611 static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) 2612 { 2613 struct the_nilfs *nilfs = sci->sc_super->s_fs_info; 2614 int flag; 2615 2616 up_write(&nilfs->ns_segctor_sem); 2617 2618 spin_lock(&sci->sc_state_lock); 2619 nilfs_segctor_kill_thread(sci); 2620 flag = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) || sci->sc_flush_request 2621 || sci->sc_seq_request != sci->sc_seq_done); 2622 spin_unlock(&sci->sc_state_lock); 2623 2624 if (flag || !nilfs_segctor_confirm(sci)) 2625 nilfs_segctor_write_out(sci); 2626 2627 if (!list_empty(&sci->sc_dirty_files)) { 2628 nilfs_warning(sci->sc_super, __func__, 2629 "dirty file(s) after the final construction\n"); 2630 nilfs_dispose_list(nilfs, &sci->sc_dirty_files, 1); 2631 } 2632 2633 WARN_ON(!list_empty(&sci->sc_segbufs)); 2634 WARN_ON(!list_empty(&sci->sc_write_logs)); 2635 2636 nilfs_put_root(sci->sc_root); 2637 2638 down_write(&nilfs->ns_segctor_sem); 2639 2640 del_timer_sync(&sci->sc_timer); 2641 kfree(sci); 2642 } 2643 2644 /** 2645 * nilfs_attach_log_writer - attach log writer 2646 * @sb: super block instance 2647 * @root: root object of the current filesystem tree 2648 * 2649 * This allocates a log writer object, initializes it, and starts the 2650 * log writer. 2651 * 2652 * Return Value: On success, 0 is returned. On error, one of the following 2653 * negative error code is returned. 2654 * 2655 * %-ENOMEM - Insufficient memory available. 2656 */ 2657 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root) 2658 { 2659 struct the_nilfs *nilfs = sb->s_fs_info; 2660 int err; 2661 2662 if (nilfs->ns_writer) { 2663 /* 2664 * This happens if the filesystem was remounted 2665 * read/write after nilfs_error degenerated it into a 2666 * read-only mount. 2667 */ 2668 nilfs_detach_log_writer(sb); 2669 } 2670 2671 nilfs->ns_writer = nilfs_segctor_new(sb, root); 2672 if (!nilfs->ns_writer) 2673 return -ENOMEM; 2674 2675 err = nilfs_segctor_start_thread(nilfs->ns_writer); 2676 if (err) { 2677 kfree(nilfs->ns_writer); 2678 nilfs->ns_writer = NULL; 2679 } 2680 return err; 2681 } 2682 2683 /** 2684 * nilfs_detach_log_writer - destroy log writer 2685 * @sb: super block instance 2686 * 2687 * This kills log writer daemon, frees the log writer object, and 2688 * destroys list of dirty files. 2689 */ 2690 void nilfs_detach_log_writer(struct super_block *sb) 2691 { 2692 struct the_nilfs *nilfs = sb->s_fs_info; 2693 LIST_HEAD(garbage_list); 2694 2695 down_write(&nilfs->ns_segctor_sem); 2696 if (nilfs->ns_writer) { 2697 nilfs_segctor_destroy(nilfs->ns_writer); 2698 nilfs->ns_writer = NULL; 2699 } 2700 2701 /* Force to free the list of dirty files */ 2702 spin_lock(&nilfs->ns_inode_lock); 2703 if (!list_empty(&nilfs->ns_dirty_files)) { 2704 list_splice_init(&nilfs->ns_dirty_files, &garbage_list); 2705 nilfs_warning(sb, __func__, 2706 "Hit dirty file after stopped log writer\n"); 2707 } 2708 spin_unlock(&nilfs->ns_inode_lock); 2709 up_write(&nilfs->ns_segctor_sem); 2710 2711 nilfs_dispose_list(nilfs, &garbage_list, 1); 2712 } 2713