1 /* 2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 3 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved. 4 * 5 * This copyrighted material is made available to anyone wishing to use, 6 * modify, copy, or redistribute it subject to the terms and conditions 7 * of the GNU General Public License version 2. 8 */ 9 10 #include <linux/sched.h> 11 #include <linux/slab.h> 12 #include <linux/spinlock.h> 13 #include <linux/completion.h> 14 #include <linux/buffer_head.h> 15 #include <linux/gfs2_ondisk.h> 16 #include <linux/crc32.h> 17 #include <linux/delay.h> 18 #include <linux/kthread.h> 19 #include <linux/freezer.h> 20 #include <linux/bio.h> 21 22 #include "gfs2.h" 23 #include "incore.h" 24 #include "bmap.h" 25 #include "glock.h" 26 #include "log.h" 27 #include "lops.h" 28 #include "meta_io.h" 29 #include "util.h" 30 #include "dir.h" 31 #include "trace_gfs2.h" 32 33 #define PULL 1 34 35 /** 36 * gfs2_struct2blk - compute stuff 37 * @sdp: the filesystem 38 * @nstruct: the number of structures 39 * @ssize: the size of the structures 40 * 41 * Compute the number of log descriptor blocks needed to hold a certain number 42 * of structures of a certain size. 43 * 44 * Returns: the number of blocks needed (minimum is always 1) 45 */ 46 47 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct, 48 unsigned int ssize) 49 { 50 unsigned int blks; 51 unsigned int first, second; 52 53 blks = 1; 54 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize; 55 56 if (nstruct > first) { 57 second = (sdp->sd_sb.sb_bsize - 58 sizeof(struct gfs2_meta_header)) / ssize; 59 blks += DIV_ROUND_UP(nstruct - first, second); 60 } 61 62 return blks; 63 } 64 65 /** 66 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters 67 * @mapping: The associated mapping (maybe NULL) 68 * @bd: The gfs2_bufdata to remove 69 * 70 * The log lock _must_ be held when calling this function 71 * 72 */ 73 74 void gfs2_remove_from_ail(struct gfs2_bufdata *bd) 75 { 76 bd->bd_ail = NULL; 77 list_del_init(&bd->bd_ail_st_list); 78 list_del_init(&bd->bd_ail_gl_list); 79 atomic_dec(&bd->bd_gl->gl_ail_count); 80 brelse(bd->bd_bh); 81 } 82 83 /** 84 * gfs2_ail1_start_one - Start I/O on a part of the AIL 85 * @sdp: the filesystem 86 * @tr: the part of the AIL 87 * 88 */ 89 90 static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai) 91 __releases(&sdp->sd_log_lock) 92 __acquires(&sdp->sd_log_lock) 93 { 94 struct gfs2_bufdata *bd, *s; 95 struct buffer_head *bh; 96 int retry; 97 98 do { 99 retry = 0; 100 101 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list, 102 bd_ail_st_list) { 103 bh = bd->bd_bh; 104 105 gfs2_assert(sdp, bd->bd_ail == ai); 106 107 if (!buffer_busy(bh)) { 108 if (!buffer_uptodate(bh)) 109 gfs2_io_error_bh(sdp, bh); 110 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list); 111 continue; 112 } 113 114 if (!buffer_dirty(bh)) 115 continue; 116 117 list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list); 118 119 get_bh(bh); 120 gfs2_log_unlock(sdp); 121 lock_buffer(bh); 122 if (test_clear_buffer_dirty(bh)) { 123 bh->b_end_io = end_buffer_write_sync; 124 submit_bh(WRITE_SYNC_PLUG, bh); 125 } else { 126 unlock_buffer(bh); 127 brelse(bh); 128 } 129 gfs2_log_lock(sdp); 130 131 retry = 1; 132 break; 133 } 134 } while (retry); 135 } 136 137 /** 138 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced 139 * @sdp: the filesystem 140 * @ai: the AIL entry 141 * 142 */ 143 144 static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags) 145 { 146 struct gfs2_bufdata *bd, *s; 147 struct buffer_head *bh; 148 149 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list, 150 bd_ail_st_list) { 151 bh = bd->bd_bh; 152 153 gfs2_assert(sdp, bd->bd_ail == ai); 154 155 if (buffer_busy(bh)) { 156 if (flags & DIO_ALL) 157 continue; 158 else 159 break; 160 } 161 162 if (!buffer_uptodate(bh)) 163 gfs2_io_error_bh(sdp, bh); 164 165 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list); 166 } 167 168 return list_empty(&ai->ai_ail1_list); 169 } 170 171 static void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags) 172 { 173 struct list_head *head; 174 u64 sync_gen; 175 struct list_head *first; 176 struct gfs2_ail *first_ai, *ai, *tmp; 177 int done = 0; 178 179 gfs2_log_lock(sdp); 180 head = &sdp->sd_ail1_list; 181 if (list_empty(head)) { 182 gfs2_log_unlock(sdp); 183 return; 184 } 185 sync_gen = sdp->sd_ail_sync_gen++; 186 187 first = head->prev; 188 first_ai = list_entry(first, struct gfs2_ail, ai_list); 189 first_ai->ai_sync_gen = sync_gen; 190 gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */ 191 192 if (flags & DIO_ALL) 193 first = NULL; 194 195 while(!done) { 196 if (first && (head->prev != first || 197 gfs2_ail1_empty_one(sdp, first_ai, 0))) 198 break; 199 200 done = 1; 201 list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) { 202 if (ai->ai_sync_gen >= sync_gen) 203 continue; 204 ai->ai_sync_gen = sync_gen; 205 gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */ 206 done = 0; 207 break; 208 } 209 } 210 211 gfs2_log_unlock(sdp); 212 } 213 214 static int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags) 215 { 216 struct gfs2_ail *ai, *s; 217 int ret; 218 219 gfs2_log_lock(sdp); 220 221 list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) { 222 if (gfs2_ail1_empty_one(sdp, ai, flags)) 223 list_move(&ai->ai_list, &sdp->sd_ail2_list); 224 else if (!(flags & DIO_ALL)) 225 break; 226 } 227 228 ret = list_empty(&sdp->sd_ail1_list); 229 230 gfs2_log_unlock(sdp); 231 232 return ret; 233 } 234 235 236 /** 237 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced 238 * @sdp: the filesystem 239 * @ai: the AIL entry 240 * 241 */ 242 243 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai) 244 { 245 struct list_head *head = &ai->ai_ail2_list; 246 struct gfs2_bufdata *bd; 247 248 while (!list_empty(head)) { 249 bd = list_entry(head->prev, struct gfs2_bufdata, 250 bd_ail_st_list); 251 gfs2_assert(sdp, bd->bd_ail == ai); 252 gfs2_remove_from_ail(bd); 253 } 254 } 255 256 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail) 257 { 258 struct gfs2_ail *ai, *safe; 259 unsigned int old_tail = sdp->sd_log_tail; 260 int wrap = (new_tail < old_tail); 261 int a, b, rm; 262 263 gfs2_log_lock(sdp); 264 265 list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) { 266 a = (old_tail <= ai->ai_first); 267 b = (ai->ai_first < new_tail); 268 rm = (wrap) ? (a || b) : (a && b); 269 if (!rm) 270 continue; 271 272 gfs2_ail2_empty_one(sdp, ai); 273 list_del(&ai->ai_list); 274 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list)); 275 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list)); 276 kfree(ai); 277 } 278 279 gfs2_log_unlock(sdp); 280 } 281 282 /** 283 * gfs2_log_reserve - Make a log reservation 284 * @sdp: The GFS2 superblock 285 * @blks: The number of blocks to reserve 286 * 287 * Note that we never give out the last few blocks of the journal. Thats 288 * due to the fact that there is a small number of header blocks 289 * associated with each log flush. The exact number can't be known until 290 * flush time, so we ensure that we have just enough free blocks at all 291 * times to avoid running out during a log flush. 292 * 293 * Returns: errno 294 */ 295 296 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks) 297 { 298 unsigned int try = 0; 299 unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize); 300 301 if (gfs2_assert_warn(sdp, blks) || 302 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks)) 303 return -EINVAL; 304 305 mutex_lock(&sdp->sd_log_reserve_mutex); 306 gfs2_log_lock(sdp); 307 while(atomic_read(&sdp->sd_log_blks_free) <= (blks + reserved_blks)) { 308 gfs2_log_unlock(sdp); 309 gfs2_ail1_empty(sdp, 0); 310 gfs2_log_flush(sdp, NULL); 311 312 if (try++) 313 gfs2_ail1_start(sdp, 0); 314 gfs2_log_lock(sdp); 315 } 316 atomic_sub(blks, &sdp->sd_log_blks_free); 317 trace_gfs2_log_blocks(sdp, -blks); 318 gfs2_log_unlock(sdp); 319 mutex_unlock(&sdp->sd_log_reserve_mutex); 320 321 down_read(&sdp->sd_log_flush_lock); 322 323 return 0; 324 } 325 326 /** 327 * gfs2_log_release - Release a given number of log blocks 328 * @sdp: The GFS2 superblock 329 * @blks: The number of blocks 330 * 331 */ 332 333 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) 334 { 335 336 gfs2_log_lock(sdp); 337 atomic_add(blks, &sdp->sd_log_blks_free); 338 trace_gfs2_log_blocks(sdp, blks); 339 gfs2_assert_withdraw(sdp, 340 atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks); 341 gfs2_log_unlock(sdp); 342 up_read(&sdp->sd_log_flush_lock); 343 } 344 345 static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn) 346 { 347 struct gfs2_journal_extent *je; 348 349 list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) { 350 if (lbn >= je->lblock && lbn < je->lblock + je->blocks) 351 return je->dblock + lbn - je->lblock; 352 } 353 354 return -1; 355 } 356 357 /** 358 * log_distance - Compute distance between two journal blocks 359 * @sdp: The GFS2 superblock 360 * @newer: The most recent journal block of the pair 361 * @older: The older journal block of the pair 362 * 363 * Compute the distance (in the journal direction) between two 364 * blocks in the journal 365 * 366 * Returns: the distance in blocks 367 */ 368 369 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer, 370 unsigned int older) 371 { 372 int dist; 373 374 dist = newer - older; 375 if (dist < 0) 376 dist += sdp->sd_jdesc->jd_blocks; 377 378 return dist; 379 } 380 381 /** 382 * calc_reserved - Calculate the number of blocks to reserve when 383 * refunding a transaction's unused buffers. 384 * @sdp: The GFS2 superblock 385 * 386 * This is complex. We need to reserve room for all our currently used 387 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and 388 * all our journaled data buffers for journaled files (e.g. files in the 389 * meta_fs like rindex, or files for which chattr +j was done.) 390 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush 391 * will count it as free space (sd_log_blks_free) and corruption will follow. 392 * 393 * We can have metadata bufs and jdata bufs in the same journal. So each 394 * type gets its own log header, for which we need to reserve a block. 395 * In fact, each type has the potential for needing more than one header 396 * in cases where we have more buffers than will fit on a journal page. 397 * Metadata journal entries take up half the space of journaled buffer entries. 398 * Thus, metadata entries have buf_limit (502) and journaled buffers have 399 * databuf_limit (251) before they cause a wrap around. 400 * 401 * Also, we need to reserve blocks for revoke journal entries and one for an 402 * overall header for the lot. 403 * 404 * Returns: the number of blocks reserved 405 */ 406 static unsigned int calc_reserved(struct gfs2_sbd *sdp) 407 { 408 unsigned int reserved = 0; 409 unsigned int mbuf_limit, metabufhdrs_needed; 410 unsigned int dbuf_limit, databufhdrs_needed; 411 unsigned int revokes = 0; 412 413 mbuf_limit = buf_limit(sdp); 414 metabufhdrs_needed = (sdp->sd_log_commited_buf + 415 (mbuf_limit - 1)) / mbuf_limit; 416 dbuf_limit = databuf_limit(sdp); 417 databufhdrs_needed = (sdp->sd_log_commited_databuf + 418 (dbuf_limit - 1)) / dbuf_limit; 419 420 if (sdp->sd_log_commited_revoke > 0) 421 revokes = gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke, 422 sizeof(u64)); 423 424 reserved = sdp->sd_log_commited_buf + metabufhdrs_needed + 425 sdp->sd_log_commited_databuf + databufhdrs_needed + 426 revokes; 427 /* One for the overall header */ 428 if (reserved) 429 reserved++; 430 return reserved; 431 } 432 433 static unsigned int current_tail(struct gfs2_sbd *sdp) 434 { 435 struct gfs2_ail *ai; 436 unsigned int tail; 437 438 gfs2_log_lock(sdp); 439 440 if (list_empty(&sdp->sd_ail1_list)) { 441 tail = sdp->sd_log_head; 442 } else { 443 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list); 444 tail = ai->ai_first; 445 } 446 447 gfs2_log_unlock(sdp); 448 449 return tail; 450 } 451 452 void gfs2_log_incr_head(struct gfs2_sbd *sdp) 453 { 454 if (sdp->sd_log_flush_head == sdp->sd_log_tail) 455 BUG_ON(sdp->sd_log_flush_head != sdp->sd_log_head); 456 457 if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) { 458 sdp->sd_log_flush_head = 0; 459 sdp->sd_log_flush_wrapped = 1; 460 } 461 } 462 463 /** 464 * gfs2_log_write_endio - End of I/O for a log buffer 465 * @bh: The buffer head 466 * @uptodate: I/O Status 467 * 468 */ 469 470 static void gfs2_log_write_endio(struct buffer_head *bh, int uptodate) 471 { 472 struct gfs2_sbd *sdp = bh->b_private; 473 bh->b_private = NULL; 474 475 end_buffer_write_sync(bh, uptodate); 476 if (atomic_dec_and_test(&sdp->sd_log_in_flight)) 477 wake_up(&sdp->sd_log_flush_wait); 478 } 479 480 /** 481 * gfs2_log_get_buf - Get and initialize a buffer to use for log control data 482 * @sdp: The GFS2 superblock 483 * 484 * Returns: the buffer_head 485 */ 486 487 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp) 488 { 489 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head); 490 struct buffer_head *bh; 491 492 bh = sb_getblk(sdp->sd_vfs, blkno); 493 lock_buffer(bh); 494 memset(bh->b_data, 0, bh->b_size); 495 set_buffer_uptodate(bh); 496 clear_buffer_dirty(bh); 497 gfs2_log_incr_head(sdp); 498 atomic_inc(&sdp->sd_log_in_flight); 499 bh->b_private = sdp; 500 bh->b_end_io = gfs2_log_write_endio; 501 502 return bh; 503 } 504 505 /** 506 * gfs2_fake_write_endio - 507 * @bh: The buffer head 508 * @uptodate: The I/O Status 509 * 510 */ 511 512 static void gfs2_fake_write_endio(struct buffer_head *bh, int uptodate) 513 { 514 struct buffer_head *real_bh = bh->b_private; 515 struct gfs2_bufdata *bd = real_bh->b_private; 516 struct gfs2_sbd *sdp = bd->bd_gl->gl_sbd; 517 518 end_buffer_write_sync(bh, uptodate); 519 free_buffer_head(bh); 520 unlock_buffer(real_bh); 521 brelse(real_bh); 522 if (atomic_dec_and_test(&sdp->sd_log_in_flight)) 523 wake_up(&sdp->sd_log_flush_wait); 524 } 525 526 /** 527 * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log 528 * @sdp: the filesystem 529 * @data: the data the buffer_head should point to 530 * 531 * Returns: the log buffer descriptor 532 */ 533 534 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp, 535 struct buffer_head *real) 536 { 537 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head); 538 struct buffer_head *bh; 539 540 bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL); 541 atomic_set(&bh->b_count, 1); 542 bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate) | (1 << BH_Lock); 543 set_bh_page(bh, real->b_page, bh_offset(real)); 544 bh->b_blocknr = blkno; 545 bh->b_size = sdp->sd_sb.sb_bsize; 546 bh->b_bdev = sdp->sd_vfs->s_bdev; 547 bh->b_private = real; 548 bh->b_end_io = gfs2_fake_write_endio; 549 550 gfs2_log_incr_head(sdp); 551 atomic_inc(&sdp->sd_log_in_flight); 552 553 return bh; 554 } 555 556 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail) 557 { 558 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail); 559 560 ail2_empty(sdp, new_tail); 561 562 gfs2_log_lock(sdp); 563 atomic_add(dist, &sdp->sd_log_blks_free); 564 trace_gfs2_log_blocks(sdp, dist); 565 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= sdp->sd_jdesc->jd_blocks); 566 gfs2_log_unlock(sdp); 567 568 sdp->sd_log_tail = new_tail; 569 } 570 571 /** 572 * log_write_header - Get and initialize a journal header buffer 573 * @sdp: The GFS2 superblock 574 * 575 * Returns: the initialized log buffer descriptor 576 */ 577 578 static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull) 579 { 580 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head); 581 struct buffer_head *bh; 582 struct gfs2_log_header *lh; 583 unsigned int tail; 584 u32 hash; 585 586 bh = sb_getblk(sdp->sd_vfs, blkno); 587 lock_buffer(bh); 588 memset(bh->b_data, 0, bh->b_size); 589 set_buffer_uptodate(bh); 590 clear_buffer_dirty(bh); 591 592 gfs2_ail1_empty(sdp, 0); 593 tail = current_tail(sdp); 594 595 lh = (struct gfs2_log_header *)bh->b_data; 596 memset(lh, 0, sizeof(struct gfs2_log_header)); 597 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC); 598 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH); 599 lh->lh_header.__pad0 = cpu_to_be64(0); 600 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH); 601 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid); 602 lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++); 603 lh->lh_flags = cpu_to_be32(flags); 604 lh->lh_tail = cpu_to_be32(tail); 605 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head); 606 hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header)); 607 lh->lh_hash = cpu_to_be32(hash); 608 609 bh->b_end_io = end_buffer_write_sync; 610 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) 611 goto skip_barrier; 612 get_bh(bh); 613 submit_bh(WRITE_SYNC | (1 << BIO_RW_BARRIER) | (1 << BIO_RW_META), bh); 614 wait_on_buffer(bh); 615 if (buffer_eopnotsupp(bh)) { 616 clear_buffer_eopnotsupp(bh); 617 set_buffer_uptodate(bh); 618 set_bit(SDF_NOBARRIERS, &sdp->sd_flags); 619 lock_buffer(bh); 620 skip_barrier: 621 get_bh(bh); 622 submit_bh(WRITE_SYNC | (1 << BIO_RW_META), bh); 623 wait_on_buffer(bh); 624 } 625 if (!buffer_uptodate(bh)) 626 gfs2_io_error_bh(sdp, bh); 627 brelse(bh); 628 629 if (sdp->sd_log_tail != tail) 630 log_pull_tail(sdp, tail); 631 else 632 gfs2_assert_withdraw(sdp, !pull); 633 634 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head); 635 gfs2_log_incr_head(sdp); 636 } 637 638 static void log_flush_commit(struct gfs2_sbd *sdp) 639 { 640 DEFINE_WAIT(wait); 641 642 if (atomic_read(&sdp->sd_log_in_flight)) { 643 do { 644 prepare_to_wait(&sdp->sd_log_flush_wait, &wait, 645 TASK_UNINTERRUPTIBLE); 646 if (atomic_read(&sdp->sd_log_in_flight)) 647 io_schedule(); 648 } while(atomic_read(&sdp->sd_log_in_flight)); 649 finish_wait(&sdp->sd_log_flush_wait, &wait); 650 } 651 652 log_write_header(sdp, 0, 0); 653 } 654 655 static void gfs2_ordered_write(struct gfs2_sbd *sdp) 656 { 657 struct gfs2_bufdata *bd; 658 struct buffer_head *bh; 659 LIST_HEAD(written); 660 661 gfs2_log_lock(sdp); 662 while (!list_empty(&sdp->sd_log_le_ordered)) { 663 bd = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_bufdata, bd_le.le_list); 664 list_move(&bd->bd_le.le_list, &written); 665 bh = bd->bd_bh; 666 if (!buffer_dirty(bh)) 667 continue; 668 get_bh(bh); 669 gfs2_log_unlock(sdp); 670 lock_buffer(bh); 671 if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) { 672 bh->b_end_io = end_buffer_write_sync; 673 submit_bh(WRITE_SYNC_PLUG, bh); 674 } else { 675 unlock_buffer(bh); 676 brelse(bh); 677 } 678 gfs2_log_lock(sdp); 679 } 680 list_splice(&written, &sdp->sd_log_le_ordered); 681 gfs2_log_unlock(sdp); 682 } 683 684 static void gfs2_ordered_wait(struct gfs2_sbd *sdp) 685 { 686 struct gfs2_bufdata *bd; 687 struct buffer_head *bh; 688 689 gfs2_log_lock(sdp); 690 while (!list_empty(&sdp->sd_log_le_ordered)) { 691 bd = list_entry(sdp->sd_log_le_ordered.prev, struct gfs2_bufdata, bd_le.le_list); 692 bh = bd->bd_bh; 693 if (buffer_locked(bh)) { 694 get_bh(bh); 695 gfs2_log_unlock(sdp); 696 wait_on_buffer(bh); 697 brelse(bh); 698 gfs2_log_lock(sdp); 699 continue; 700 } 701 list_del_init(&bd->bd_le.le_list); 702 } 703 gfs2_log_unlock(sdp); 704 } 705 706 /** 707 * gfs2_log_flush - flush incore transaction(s) 708 * @sdp: the filesystem 709 * @gl: The glock structure to flush. If NULL, flush the whole incore log 710 * 711 */ 712 713 void __gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl) 714 { 715 struct gfs2_ail *ai; 716 717 down_write(&sdp->sd_log_flush_lock); 718 719 /* Log might have been flushed while we waited for the flush lock */ 720 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) { 721 up_write(&sdp->sd_log_flush_lock); 722 return; 723 } 724 trace_gfs2_log_flush(sdp, 1); 725 726 ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL); 727 INIT_LIST_HEAD(&ai->ai_ail1_list); 728 INIT_LIST_HEAD(&ai->ai_ail2_list); 729 730 if (sdp->sd_log_num_buf != sdp->sd_log_commited_buf) { 731 printk(KERN_INFO "GFS2: log buf %u %u\n", sdp->sd_log_num_buf, 732 sdp->sd_log_commited_buf); 733 gfs2_assert_withdraw(sdp, 0); 734 } 735 if (sdp->sd_log_num_databuf != sdp->sd_log_commited_databuf) { 736 printk(KERN_INFO "GFS2: log databuf %u %u\n", 737 sdp->sd_log_num_databuf, sdp->sd_log_commited_databuf); 738 gfs2_assert_withdraw(sdp, 0); 739 } 740 gfs2_assert_withdraw(sdp, 741 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke); 742 743 sdp->sd_log_flush_head = sdp->sd_log_head; 744 sdp->sd_log_flush_wrapped = 0; 745 ai->ai_first = sdp->sd_log_flush_head; 746 747 gfs2_ordered_write(sdp); 748 lops_before_commit(sdp); 749 gfs2_ordered_wait(sdp); 750 751 if (sdp->sd_log_head != sdp->sd_log_flush_head) 752 log_flush_commit(sdp); 753 else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){ 754 gfs2_log_lock(sdp); 755 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */ 756 trace_gfs2_log_blocks(sdp, -1); 757 gfs2_log_unlock(sdp); 758 log_write_header(sdp, 0, PULL); 759 } 760 lops_after_commit(sdp, ai); 761 762 gfs2_log_lock(sdp); 763 sdp->sd_log_head = sdp->sd_log_flush_head; 764 sdp->sd_log_blks_reserved = 0; 765 sdp->sd_log_commited_buf = 0; 766 sdp->sd_log_commited_databuf = 0; 767 sdp->sd_log_commited_revoke = 0; 768 769 if (!list_empty(&ai->ai_ail1_list)) { 770 list_add(&ai->ai_list, &sdp->sd_ail1_list); 771 ai = NULL; 772 } 773 gfs2_log_unlock(sdp); 774 trace_gfs2_log_flush(sdp, 0); 775 up_write(&sdp->sd_log_flush_lock); 776 777 kfree(ai); 778 } 779 780 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 781 { 782 unsigned int reserved; 783 unsigned int unused; 784 785 gfs2_log_lock(sdp); 786 787 sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm; 788 sdp->sd_log_commited_databuf += tr->tr_num_databuf_new - 789 tr->tr_num_databuf_rm; 790 gfs2_assert_withdraw(sdp, (((int)sdp->sd_log_commited_buf) >= 0) || 791 (((int)sdp->sd_log_commited_databuf) >= 0)); 792 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm; 793 reserved = calc_reserved(sdp); 794 gfs2_assert_withdraw(sdp, sdp->sd_log_blks_reserved + tr->tr_reserved >= reserved); 795 unused = sdp->sd_log_blks_reserved - reserved + tr->tr_reserved; 796 atomic_add(unused, &sdp->sd_log_blks_free); 797 trace_gfs2_log_blocks(sdp, unused); 798 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= 799 sdp->sd_jdesc->jd_blocks); 800 sdp->sd_log_blks_reserved = reserved; 801 802 gfs2_log_unlock(sdp); 803 } 804 805 static void buf_lo_incore_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 806 { 807 struct list_head *head = &tr->tr_list_buf; 808 struct gfs2_bufdata *bd; 809 810 gfs2_log_lock(sdp); 811 while (!list_empty(head)) { 812 bd = list_entry(head->next, struct gfs2_bufdata, bd_list_tr); 813 list_del_init(&bd->bd_list_tr); 814 tr->tr_num_buf--; 815 } 816 gfs2_log_unlock(sdp); 817 gfs2_assert_warn(sdp, !tr->tr_num_buf); 818 } 819 820 /** 821 * gfs2_log_commit - Commit a transaction to the log 822 * @sdp: the filesystem 823 * @tr: the transaction 824 * 825 * Returns: errno 826 */ 827 828 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 829 { 830 log_refund(sdp, tr); 831 buf_lo_incore_commit(sdp, tr); 832 833 up_read(&sdp->sd_log_flush_lock); 834 835 gfs2_log_lock(sdp); 836 if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks)) 837 wake_up_process(sdp->sd_logd_process); 838 gfs2_log_unlock(sdp); 839 } 840 841 /** 842 * gfs2_log_shutdown - write a shutdown header into a journal 843 * @sdp: the filesystem 844 * 845 */ 846 847 void gfs2_log_shutdown(struct gfs2_sbd *sdp) 848 { 849 down_write(&sdp->sd_log_flush_lock); 850 851 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved); 852 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf); 853 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); 854 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg); 855 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf); 856 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list)); 857 858 sdp->sd_log_flush_head = sdp->sd_log_head; 859 sdp->sd_log_flush_wrapped = 0; 860 861 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 862 (sdp->sd_log_tail == current_tail(sdp)) ? 0 : PULL); 863 864 gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks); 865 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail); 866 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list)); 867 868 sdp->sd_log_head = sdp->sd_log_flush_head; 869 sdp->sd_log_tail = sdp->sd_log_head; 870 871 up_write(&sdp->sd_log_flush_lock); 872 } 873 874 875 /** 876 * gfs2_meta_syncfs - sync all the buffers in a filesystem 877 * @sdp: the filesystem 878 * 879 */ 880 881 void gfs2_meta_syncfs(struct gfs2_sbd *sdp) 882 { 883 gfs2_log_flush(sdp, NULL); 884 for (;;) { 885 gfs2_ail1_start(sdp, DIO_ALL); 886 if (gfs2_ail1_empty(sdp, DIO_ALL)) 887 break; 888 msleep(10); 889 } 890 } 891 892 893 /** 894 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks 895 * @sdp: Pointer to GFS2 superblock 896 * 897 * Also, periodically check to make sure that we're using the most recent 898 * journal index. 899 */ 900 901 int gfs2_logd(void *data) 902 { 903 struct gfs2_sbd *sdp = data; 904 unsigned long t; 905 int need_flush; 906 907 while (!kthread_should_stop()) { 908 /* Advance the log tail */ 909 910 t = sdp->sd_log_flush_time + 911 gfs2_tune_get(sdp, gt_log_flush_secs) * HZ; 912 913 gfs2_ail1_empty(sdp, DIO_ALL); 914 gfs2_log_lock(sdp); 915 need_flush = sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks); 916 gfs2_log_unlock(sdp); 917 if (need_flush || time_after_eq(jiffies, t)) { 918 gfs2_log_flush(sdp, NULL); 919 sdp->sd_log_flush_time = jiffies; 920 } 921 922 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ; 923 if (freezing(current)) 924 refrigerator(); 925 schedule_timeout_interruptible(t); 926 } 927 928 return 0; 929 } 930 931