fs/gfs2/log.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
   5  */
   6
   7 #include <linux/sched.h>
   8 #include <linux/slab.h>
   9 #include <linux/spinlock.h>
  10 #include <linux/completion.h>
  11 #include <linux/buffer_head.h>
  12 #include <linux/gfs2_ondisk.h>
  13 #include <linux/crc32.h>
  14 #include <linux/crc32c.h>
  15 #include <linux/delay.h>
  16 #include <linux/kthread.h>
  17 #include <linux/freezer.h>
  18 #include <linux/bio.h>
  19 #include <linux/blkdev.h>
  20 #include <linux/writeback.h>
  21 #include <linux/list_sort.h>
  22
  23 #include "gfs2.h"
  24 #include "incore.h"
  25 #include "bmap.h"
  26 #include "glock.h"
  27 #include "log.h"
  28 #include "lops.h"
  29 #include "meta_io.h"
  30 #include "util.h"
  31 #include "dir.h"
  32 #include "trace_gfs2.h"
  33
  34 static void gfs2_log_shutdown(struct gfs2_sbd *sdp);
  35
  36 /**
  37  * gfs2_struct2blk - compute stuff
  38  * @sdp: the filesystem
  39  * @nstruct: the number of 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 {
  49         unsigned int blks;
  50         unsigned int first, second;
  51
  52         blks = 1;
  53         first = sdp->sd_ldptrs;
  54
  55         if (nstruct > first) {
  56                 second = sdp->sd_inptrs;
  57                 blks += DIV_ROUND_UP(nstruct - first, second);
  58         }
  59
  60         return blks;
  61 }
  62
  63 /**
  64  * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
  65  * @mapping: The associated mapping (maybe NULL)
  66  * @bd: The gfs2_bufdata to remove
  67  *
  68  * The ail lock _must_ be held when calling this function
  69  *
  70  */
  71
  72 static void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
  73 {
  74         bd->bd_tr = NULL;
  75         list_del_init(&bd->bd_ail_st_list);
  76         list_del_init(&bd->bd_ail_gl_list);
  77         atomic_dec(&bd->bd_gl->gl_ail_count);
  78         brelse(bd->bd_bh);
  79 }
  80
  81 /**
  82  * gfs2_ail1_start_one - Start I/O on a part of the AIL
  83  * @sdp: the filesystem
  84  * @wbc: The writeback control structure
  85  * @ai: The ail structure
  86  *
  87  */
  88
  89 static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
  90                                struct writeback_control *wbc,
  91                                struct gfs2_trans *tr,
  92                                bool *withdraw)
  93 __releases(&sdp->sd_ail_lock)
  94 __acquires(&sdp->sd_ail_lock)
  95 {
  96         struct gfs2_glock *gl = NULL;
  97         struct address_space *mapping;
  98         struct gfs2_bufdata *bd, *s;
  99         struct buffer_head *bh;
 100
 101         list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
 102                 bh = bd->bd_bh;
 103
 104                 gfs2_assert(sdp, bd->bd_tr == tr);
 105
 106                 if (!buffer_busy(bh)) {
 107                         if (!buffer_uptodate(bh) &&
 108                             !test_and_set_bit(SDF_AIL1_IO_ERROR,
 109                                               &sdp->sd_flags)) {
 110                                 gfs2_io_error_bh(sdp, bh);
 111                                 *withdraw = true;
 112                         }
 113                         list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
 114                         continue;
 115                 }
 116
 117                 if (!buffer_dirty(bh))
 118                         continue;
 119                 if (gl == bd->bd_gl)
 120                         continue;
 121                 gl = bd->bd_gl;
 122                 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
 123                 mapping = bh->b_page->mapping;
 124                 if (!mapping)
 125                         continue;
 126                 spin_unlock(&sdp->sd_ail_lock);
 127                 generic_writepages(mapping, wbc);
 128                 spin_lock(&sdp->sd_ail_lock);
 129                 if (wbc->nr_to_write <= 0)
 130                         break;
 131                 return 1;
 132         }
 133
 134         return 0;
 135 }
 136
 137
 138 /**
 139  * gfs2_ail1_flush - start writeback of some ail1 entries
 140  * @sdp: The super block
 141  * @wbc: The writeback control structure
 142  *
 143  * Writes back some ail1 entries, according to the limits in the
 144  * writeback control structure
 145  */
 146
 147 void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
 148 {
 149         struct list_head *head = &sdp->sd_ail1_list;
 150         struct gfs2_trans *tr;
 151         struct blk_plug plug;
 152         bool withdraw = false;
 153
 154         trace_gfs2_ail_flush(sdp, wbc, 1);
 155         blk_start_plug(&plug);
 156         spin_lock(&sdp->sd_ail_lock);
 157 restart:
 158         list_for_each_entry_reverse(tr, head, tr_list) {
 159                 if (wbc->nr_to_write <= 0)
 160                         break;
 161                 if (gfs2_ail1_start_one(sdp, wbc, tr, &withdraw) &&
 162                     !gfs2_withdrawn(sdp))
 163                         goto restart;
 164         }
 165         spin_unlock(&sdp->sd_ail_lock);
 166         blk_finish_plug(&plug);
 167         if (withdraw)
 168                 gfs2_lm_withdraw(sdp, NULL);
 169         trace_gfs2_ail_flush(sdp, wbc, 0);
 170 }
 171
 172 /**
 173  * gfs2_ail1_start - start writeback of all ail1 entries
 174  * @sdp: The superblock
 175  */
 176
 177 static void gfs2_ail1_start(struct gfs2_sbd *sdp)
 178 {
 179         struct writeback_control wbc = {
 180                 .sync_mode = WB_SYNC_NONE,
 181                 .nr_to_write = LONG_MAX,
 182                 .range_start = 0,
 183                 .range_end = LLONG_MAX,
 184         };
 185
 186         return gfs2_ail1_flush(sdp, &wbc);
 187 }
 188
 189 /**
 190  * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
 191  * @sdp: the filesystem
 192  * @ai: the AIL entry
 193  *
 194  */
 195
 196 static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
 197                                 bool *withdraw)
 198 {
 199         struct gfs2_bufdata *bd, *s;
 200         struct buffer_head *bh;
 201
 202         list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
 203                                          bd_ail_st_list) {
 204                 bh = bd->bd_bh;
 205                 gfs2_assert(sdp, bd->bd_tr == tr);
 206                 if (buffer_busy(bh))
 207                         continue;
 208                 if (!buffer_uptodate(bh) &&
 209                     !test_and_set_bit(SDF_AIL1_IO_ERROR, &sdp->sd_flags)) {
 210                         gfs2_io_error_bh(sdp, bh);
 211                         *withdraw = true;
 212                 }
 213                 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
 214         }
 215 }
 216
 217 /**
 218  * gfs2_ail1_empty - Try to empty the ail1 lists
 219  * @sdp: The superblock
 220  *
 221  * Tries to empty the ail1 lists, starting with the oldest first
 222  */
 223
 224 static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
 225 {
 226         struct gfs2_trans *tr, *s;
 227         int oldest_tr = 1;
 228         int ret;
 229         bool withdraw = false;
 230
 231         spin_lock(&sdp->sd_ail_lock);
 232         list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
 233                 gfs2_ail1_empty_one(sdp, tr, &withdraw);
 234                 if (list_empty(&tr->tr_ail1_list) && oldest_tr)
 235                         list_move(&tr->tr_list, &sdp->sd_ail2_list);
 236                 else
 237                         oldest_tr = 0;
 238         }
 239         ret = list_empty(&sdp->sd_ail1_list);
 240         spin_unlock(&sdp->sd_ail_lock);
 241
 242         if (withdraw)
 243                 gfs2_lm_withdraw(sdp, "fatal: I/O error(s)\n");
 244
 245         return ret;
 246 }
 247
 248 static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
 249 {
 250         struct gfs2_trans *tr;
 251         struct gfs2_bufdata *bd;
 252         struct buffer_head *bh;
 253
 254         spin_lock(&sdp->sd_ail_lock);
 255         list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
 256                 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
 257                         bh = bd->bd_bh;
 258                         if (!buffer_locked(bh))
 259                                 continue;
 260                         get_bh(bh);
 261                         spin_unlock(&sdp->sd_ail_lock);
 262                         wait_on_buffer(bh);
 263                         brelse(bh);
 264                         return;
 265                 }
 266         }
 267         spin_unlock(&sdp->sd_ail_lock);
 268 }
 269
 270 /**
 271  * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
 272  * @sdp: the filesystem
 273  * @ai: the AIL entry
 274  *
 275  */
 276
 277 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 278 {
 279         struct list_head *head = &tr->tr_ail2_list;
 280         struct gfs2_bufdata *bd;
 281
 282         while (!list_empty(head)) {
 283                 bd = list_entry(head->prev, struct gfs2_bufdata,
 284                                 bd_ail_st_list);
 285                 gfs2_assert(sdp, bd->bd_tr == tr);
 286                 gfs2_remove_from_ail(bd);
 287         }
 288 }
 289
 290 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
 291 {
 292         struct gfs2_trans *tr, *safe;
 293         unsigned int old_tail = sdp->sd_log_tail;
 294         int wrap = (new_tail < old_tail);
 295         int a, b, rm;
 296
 297         spin_lock(&sdp->sd_ail_lock);
 298
 299         list_for_each_entry_safe(tr, safe, &sdp->sd_ail2_list, tr_list) {
 300                 a = (old_tail <= tr->tr_first);
 301                 b = (tr->tr_first < new_tail);
 302                 rm = (wrap) ? (a || b) : (a && b);
 303                 if (!rm)
 304                         continue;
 305
 306                 gfs2_ail2_empty_one(sdp, tr);
 307                 list_del(&tr->tr_list);
 308                 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
 309                 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
 310                 kfree(tr);
 311         }
 312
 313         spin_unlock(&sdp->sd_ail_lock);
 314 }
 315
 316 /**
 317  * gfs2_log_release - Release a given number of log blocks
 318  * @sdp: The GFS2 superblock
 319  * @blks: The number of blocks
 320  *
 321  */
 322
 323 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
 324 {
 325
 326         atomic_add(blks, &sdp->sd_log_blks_free);
 327         trace_gfs2_log_blocks(sdp, blks);
 328         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
 329                                   sdp->sd_jdesc->jd_blocks);
 330         up_read(&sdp->sd_log_flush_lock);
 331 }
 332
 333 /**
 334  * gfs2_log_reserve - Make a log reservation
 335  * @sdp: The GFS2 superblock
 336  * @blks: The number of blocks to reserve
 337  *
 338  * Note that we never give out the last few blocks of the journal. Thats
 339  * due to the fact that there is a small number of header blocks
 340  * associated with each log flush. The exact number can't be known until
 341  * flush time, so we ensure that we have just enough free blocks at all
 342  * times to avoid running out during a log flush.
 343  *
 344  * We no longer flush the log here, instead we wake up logd to do that
 345  * for us. To avoid the thundering herd and to ensure that we deal fairly
 346  * with queued waiters, we use an exclusive wait. This means that when we
 347  * get woken with enough journal space to get our reservation, we need to
 348  * wake the next waiter on the list.
 349  *
 350  * Returns: errno
 351  */
 352
 353 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
 354 {
 355         int ret = 0;
 356         unsigned reserved_blks = 7 * (4096 / sdp->sd_vfs->s_blocksize);
 357         unsigned wanted = blks + reserved_blks;
 358         DEFINE_WAIT(wait);
 359         int did_wait = 0;
 360         unsigned int free_blocks;
 361
 362         if (gfs2_assert_warn(sdp, blks) ||
 363             gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
 364                 return -EINVAL;
 365         atomic_add(blks, &sdp->sd_log_blks_needed);
 366 retry:
 367         free_blocks = atomic_read(&sdp->sd_log_blks_free);
 368         if (unlikely(free_blocks <= wanted)) {
 369                 do {
 370                         prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
 371                                         TASK_UNINTERRUPTIBLE);
 372                         wake_up(&sdp->sd_logd_waitq);
 373                         did_wait = 1;
 374                         if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
 375                                 io_schedule();
 376                         free_blocks = atomic_read(&sdp->sd_log_blks_free);
 377                 } while(free_blocks <= wanted);
 378                 finish_wait(&sdp->sd_log_waitq, &wait);
 379         }
 380         atomic_inc(&sdp->sd_reserving_log);
 381         if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
 382                                 free_blocks - blks) != free_blocks) {
 383                 if (atomic_dec_and_test(&sdp->sd_reserving_log))
 384                         wake_up(&sdp->sd_reserving_log_wait);
 385                 goto retry;
 386         }
 387         atomic_sub(blks, &sdp->sd_log_blks_needed);
 388         trace_gfs2_log_blocks(sdp, -blks);
 389
 390         /*
 391          * If we waited, then so might others, wake them up _after_ we get
 392          * our share of the log.
 393          */
 394         if (unlikely(did_wait))
 395                 wake_up(&sdp->sd_log_waitq);
 396
 397         down_read(&sdp->sd_log_flush_lock);
 398         if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
 399                 gfs2_log_release(sdp, blks);
 400                 ret = -EROFS;
 401         }
 402         if (atomic_dec_and_test(&sdp->sd_reserving_log))
 403                 wake_up(&sdp->sd_reserving_log_wait);
 404         return ret;
 405 }
 406
 407 /**
 408  * log_distance - Compute distance between two journal blocks
 409  * @sdp: The GFS2 superblock
 410  * @newer: The most recent journal block of the pair
 411  * @older: The older journal block of the pair
 412  *
 413  *   Compute the distance (in the journal direction) between two
 414  *   blocks in the journal
 415  *
 416  * Returns: the distance in blocks
 417  */
 418
 419 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
 420                                         unsigned int older)
 421 {
 422         int dist;
 423
 424         dist = newer - older;
 425         if (dist < 0)
 426                 dist += sdp->sd_jdesc->jd_blocks;
 427
 428         return dist;
 429 }
 430
 431 /**
 432  * calc_reserved - Calculate the number of blocks to reserve when
 433  *                 refunding a transaction's unused buffers.
 434  * @sdp: The GFS2 superblock
 435  *
 436  * This is complex.  We need to reserve room for all our currently used
 437  * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
 438  * all our journaled data buffers for journaled files (e.g. files in the
 439  * meta_fs like rindex, or files for which chattr +j was done.)
 440  * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
 441  * will count it as free space (sd_log_blks_free) and corruption will follow.
 442  *
 443  * We can have metadata bufs and jdata bufs in the same journal.  So each
 444  * type gets its own log header, for which we need to reserve a block.
 445  * In fact, each type has the potential for needing more than one header
 446  * in cases where we have more buffers than will fit on a journal page.
 447  * Metadata journal entries take up half the space of journaled buffer entries.
 448  * Thus, metadata entries have buf_limit (502) and journaled buffers have
 449  * databuf_limit (251) before they cause a wrap around.
 450  *
 451  * Also, we need to reserve blocks for revoke journal entries and one for an
 452  * overall header for the lot.
 453  *
 454  * Returns: the number of blocks reserved
 455  */
 456 static unsigned int calc_reserved(struct gfs2_sbd *sdp)
 457 {
 458         unsigned int reserved = 0;
 459         unsigned int mbuf;
 460         unsigned int dbuf;
 461         struct gfs2_trans *tr = sdp->sd_log_tr;
 462
 463         if (tr) {
 464                 mbuf = tr->tr_num_buf_new - tr->tr_num_buf_rm;
 465                 dbuf = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
 466                 reserved = mbuf + dbuf;
 467                 /* Account for header blocks */
 468                 reserved += DIV_ROUND_UP(mbuf, buf_limit(sdp));
 469                 reserved += DIV_ROUND_UP(dbuf, databuf_limit(sdp));
 470         }
 471
 472         if (sdp->sd_log_committed_revoke > 0)
 473                 reserved += gfs2_struct2blk(sdp, sdp->sd_log_committed_revoke);
 474         /* One for the overall header */
 475         if (reserved)
 476                 reserved++;
 477         return reserved;
 478 }
 479
 480 static unsigned int current_tail(struct gfs2_sbd *sdp)
 481 {
 482         struct gfs2_trans *tr;
 483         unsigned int tail;
 484
 485         spin_lock(&sdp->sd_ail_lock);
 486
 487         if (list_empty(&sdp->sd_ail1_list)) {
 488                 tail = sdp->sd_log_head;
 489         } else {
 490                 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans,
 491                                 tr_list);
 492                 tail = tr->tr_first;
 493         }
 494
 495         spin_unlock(&sdp->sd_ail_lock);
 496
 497         return tail;
 498 }
 499
 500 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
 501 {
 502         unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 503
 504         ail2_empty(sdp, new_tail);
 505
 506         atomic_add(dist, &sdp->sd_log_blks_free);
 507         trace_gfs2_log_blocks(sdp, dist);
 508         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
 509                              sdp->sd_jdesc->jd_blocks);
 510
 511         sdp->sd_log_tail = new_tail;
 512 }
 513
 514
 515 static void log_flush_wait(struct gfs2_sbd *sdp)
 516 {
 517         DEFINE_WAIT(wait);
 518
 519         if (atomic_read(&sdp->sd_log_in_flight)) {
 520                 do {
 521                         prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
 522                                         TASK_UNINTERRUPTIBLE);
 523                         if (atomic_read(&sdp->sd_log_in_flight))
 524                                 io_schedule();
 525                 } while(atomic_read(&sdp->sd_log_in_flight));
 526                 finish_wait(&sdp->sd_log_flush_wait, &wait);
 527         }
 528 }
 529
 530 static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
 531 {
 532         struct gfs2_inode *ipa, *ipb;
 533
 534         ipa = list_entry(a, struct gfs2_inode, i_ordered);
 535         ipb = list_entry(b, struct gfs2_inode, i_ordered);
 536
 537         if (ipa->i_no_addr < ipb->i_no_addr)
 538                 return -1;
 539         if (ipa->i_no_addr > ipb->i_no_addr)
 540                 return 1;
 541         return 0;
 542 }
 543
 544 static void gfs2_ordered_write(struct gfs2_sbd *sdp)
 545 {
 546         struct gfs2_inode *ip;
 547         LIST_HEAD(written);
 548
 549         spin_lock(&sdp->sd_ordered_lock);
 550         list_sort(NULL, &sdp->sd_log_ordered, &ip_cmp);
 551         while (!list_empty(&sdp->sd_log_ordered)) {
 552                 ip = list_entry(sdp->sd_log_ordered.next, struct gfs2_inode, i_ordered);
 553                 if (ip->i_inode.i_mapping->nrpages == 0) {
 554                         test_and_clear_bit(GIF_ORDERED, &ip->i_flags);
 555                         list_del(&ip->i_ordered);
 556                         continue;
 557                 }
 558                 list_move(&ip->i_ordered, &written);
 559                 spin_unlock(&sdp->sd_ordered_lock);
 560                 filemap_fdatawrite(ip->i_inode.i_mapping);
 561                 spin_lock(&sdp->sd_ordered_lock);
 562         }
 563         list_splice(&written, &sdp->sd_log_ordered);
 564         spin_unlock(&sdp->sd_ordered_lock);
 565 }
 566
 567 static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
 568 {
 569         struct gfs2_inode *ip;
 570
 571         spin_lock(&sdp->sd_ordered_lock);
 572         while (!list_empty(&sdp->sd_log_ordered)) {
 573                 ip = list_entry(sdp->sd_log_ordered.next, struct gfs2_inode, i_ordered);
 574                 list_del(&ip->i_ordered);
 575                 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags));
 576                 if (ip->i_inode.i_mapping->nrpages == 0)
 577                         continue;
 578                 spin_unlock(&sdp->sd_ordered_lock);
 579                 filemap_fdatawait(ip->i_inode.i_mapping);
 580                 spin_lock(&sdp->sd_ordered_lock);
 581         }
 582         spin_unlock(&sdp->sd_ordered_lock);
 583 }
 584
 585 void gfs2_ordered_del_inode(struct gfs2_inode *ip)
 586 {
 587         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 588
 589         spin_lock(&sdp->sd_ordered_lock);
 590         if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags))
 591                 list_del(&ip->i_ordered);
 592         spin_unlock(&sdp->sd_ordered_lock);
 593 }
 594
 595 void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 596 {
 597         struct buffer_head *bh = bd->bd_bh;
 598         struct gfs2_glock *gl = bd->bd_gl;
 599
 600         bh->b_private = NULL;
 601         bd->bd_blkno = bh->b_blocknr;
 602         gfs2_remove_from_ail(bd); /* drops ref on bh */
 603         bd->bd_bh = NULL;
 604         sdp->sd_log_num_revoke++;
 605         if (atomic_inc_return(&gl->gl_revokes) == 1)
 606                 gfs2_glock_hold(gl);
 607         set_bit(GLF_LFLUSH, &gl->gl_flags);
 608         list_add(&bd->bd_list, &sdp->sd_log_revokes);
 609 }
 610
 611 void gfs2_glock_remove_revoke(struct gfs2_glock *gl)
 612 {
 613         if (atomic_dec_return(&gl->gl_revokes) == 0) {
 614                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
 615                 gfs2_glock_queue_put(gl);
 616         }
 617 }
 618
 619 void gfs2_write_revokes(struct gfs2_sbd *sdp)
 620 {
 621         struct gfs2_trans *tr;
 622         struct gfs2_bufdata *bd, *tmp;
 623         int have_revokes = 0;
 624         int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
 625
 626         gfs2_ail1_empty(sdp);
 627         spin_lock(&sdp->sd_ail_lock);
 628         list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
 629                 list_for_each_entry(bd, &tr->tr_ail2_list, bd_ail_st_list) {
 630                         if (list_empty(&bd->bd_list)) {
 631                                 have_revokes = 1;
 632                                 goto done;
 633                         }
 634                 }
 635         }
 636 done:
 637         spin_unlock(&sdp->sd_ail_lock);
 638         if (have_revokes == 0)
 639                 return;
 640         while (sdp->sd_log_num_revoke > max_revokes)
 641                 max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
 642         max_revokes -= sdp->sd_log_num_revoke;
 643         if (!sdp->sd_log_num_revoke) {
 644                 atomic_dec(&sdp->sd_log_blks_free);
 645                 /* If no blocks have been reserved, we need to also
 646                  * reserve a block for the header */
 647                 if (!sdp->sd_log_blks_reserved)
 648                         atomic_dec(&sdp->sd_log_blks_free);
 649         }
 650         gfs2_log_lock(sdp);
 651         spin_lock(&sdp->sd_ail_lock);
 652         list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
 653                 list_for_each_entry_safe(bd, tmp, &tr->tr_ail2_list, bd_ail_st_list) {
 654                         if (max_revokes == 0)
 655                                 goto out_of_blocks;
 656                         if (!list_empty(&bd->bd_list))
 657                                 continue;
 658                         gfs2_add_revoke(sdp, bd);
 659                         max_revokes--;
 660                 }
 661         }
 662 out_of_blocks:
 663         spin_unlock(&sdp->sd_ail_lock);
 664         gfs2_log_unlock(sdp);
 665
 666         if (!sdp->sd_log_num_revoke) {
 667                 atomic_inc(&sdp->sd_log_blks_free);
 668                 if (!sdp->sd_log_blks_reserved)
 669                         atomic_inc(&sdp->sd_log_blks_free);
 670         }
 671 }
 672
 673 /**
 674  * gfs2_write_log_header - Write a journal log header buffer at lblock
 675  * @sdp: The GFS2 superblock
 676  * @jd: journal descriptor of the journal to which we are writing
 677  * @seq: sequence number
 678  * @tail: tail of the log
 679  * @lblock: value for lh_blkno (block number relative to start of journal)
 680  * @flags: log header flags GFS2_LOG_HEAD_*
 681  * @op_flags: flags to pass to the bio
 682  *
 683  * Returns: the initialized log buffer descriptor
 684  */
 685
 686 void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
 687                            u64 seq, u32 tail, u32 lblock, u32 flags,
 688                            int op_flags)
 689 {
 690         struct gfs2_log_header *lh;
 691         u32 hash, crc;
 692         struct page *page;
 693         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 694         struct timespec64 tv;
 695         struct super_block *sb = sdp->sd_vfs;
 696         u64 dblock;
 697
 698         if (gfs2_withdrawn(sdp))
 699                 goto out;
 700
 701         page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
 702         lh = page_address(page);
 703         clear_page(lh);
 704
 705         lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 706         lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
 707         lh->lh_header.__pad0 = cpu_to_be64(0);
 708         lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
 709         lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 710         lh->lh_sequence = cpu_to_be64(seq);
 711         lh->lh_flags = cpu_to_be32(flags);
 712         lh->lh_tail = cpu_to_be32(tail);
 713         lh->lh_blkno = cpu_to_be32(lblock);
 714         hash = ~crc32(~0, lh, LH_V1_SIZE);
 715         lh->lh_hash = cpu_to_be32(hash);
 716
 717         ktime_get_coarse_real_ts64(&tv);
 718         lh->lh_nsec = cpu_to_be32(tv.tv_nsec);
 719         lh->lh_sec = cpu_to_be64(tv.tv_sec);
 720         if (!list_empty(&jd->extent_list))
 721                 dblock = gfs2_log_bmap(jd, lblock);
 722         else {
 723                 int ret = gfs2_lblk_to_dblk(jd->jd_inode, lblock, &dblock);
 724                 if (gfs2_assert_withdraw(sdp, ret == 0))
 725                         return;
 726         }
 727         lh->lh_addr = cpu_to_be64(dblock);
 728         lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr);
 729
 730         /* We may only write local statfs, quota, etc., when writing to our
 731            own journal. The values are left 0 when recovering a journal
 732            different from our own. */
 733         if (!(flags & GFS2_LOG_HEAD_RECOVERY)) {
 734                 lh->lh_statfs_addr =
 735                         cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr);
 736                 lh->lh_quota_addr =
 737                         cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr);
 738
 739                 spin_lock(&sdp->sd_statfs_spin);
 740                 lh->lh_local_total = cpu_to_be64(l_sc->sc_total);
 741                 lh->lh_local_free = cpu_to_be64(l_sc->sc_free);
 742                 lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes);
 743                 spin_unlock(&sdp->sd_statfs_spin);
 744         }
 745
 746         BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE);
 747
 748         crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
 749                      sb->s_blocksize - LH_V1_SIZE - 4);
 750         lh->lh_crc = cpu_to_be32(crc);
 751
 752         gfs2_log_write(sdp, page, sb->s_blocksize, 0, dblock);
 753         gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE | op_flags);
 754 out:
 755         log_flush_wait(sdp);
 756 }
 757
 758 /**
 759  * log_write_header - Get and initialize a journal header buffer
 760  * @sdp: The GFS2 superblock
 761  * @flags: The log header flags, including log header origin
 762  *
 763  * Returns: the initialized log buffer descriptor
 764  */
 765
 766 static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
 767 {
 768         unsigned int tail;
 769         int op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC;
 770         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 771
 772         gfs2_assert_withdraw(sdp, (state != SFS_FROZEN));
 773         tail = current_tail(sdp);
 774
 775         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
 776                 gfs2_ordered_wait(sdp);
 777                 log_flush_wait(sdp);
 778                 op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
 779         }
 780         sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
 781         gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++, tail,
 782                               sdp->sd_log_flush_head, flags, op_flags);
 783         gfs2_log_incr_head(sdp);
 784
 785         if (sdp->sd_log_tail != tail)
 786                 log_pull_tail(sdp, tail);
 787 }
 788
 789 /**
 790  * gfs2_log_flush - flush incore transaction(s)
 791  * @sdp: the filesystem
 792  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
 793  * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags
 794  *
 795  */
 796
 797 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)
 798 {
 799         struct gfs2_trans *tr;
 800         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 801
 802         down_write(&sdp->sd_log_flush_lock);
 803
 804         /* Log might have been flushed while we waited for the flush lock */
 805         if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
 806                 up_write(&sdp->sd_log_flush_lock);
 807                 return;
 808         }
 809         trace_gfs2_log_flush(sdp, 1, flags);
 810
 811         if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN)
 812                 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 813
 814         sdp->sd_log_flush_head = sdp->sd_log_head;
 815         tr = sdp->sd_log_tr;
 816         if (tr) {
 817                 sdp->sd_log_tr = NULL;
 818                 INIT_LIST_HEAD(&tr->tr_ail1_list);
 819                 INIT_LIST_HEAD(&tr->tr_ail2_list);
 820                 tr->tr_first = sdp->sd_log_flush_head;
 821                 if (unlikely (state == SFS_FROZEN))
 822                         gfs2_assert_withdraw(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new);
 823         }
 824
 825         if (unlikely(state == SFS_FROZEN))
 826                 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 827         gfs2_assert_withdraw(sdp,
 828                         sdp->sd_log_num_revoke == sdp->sd_log_committed_revoke);
 829
 830         gfs2_ordered_write(sdp);
 831         lops_before_commit(sdp, tr);
 832         gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE);
 833
 834         if (sdp->sd_log_head != sdp->sd_log_flush_head) {
 835                 log_flush_wait(sdp);
 836                 log_write_header(sdp, flags);
 837         } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
 838                 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
 839                 trace_gfs2_log_blocks(sdp, -1);
 840                 log_write_header(sdp, flags);
 841         }
 842         lops_after_commit(sdp, tr);
 843
 844         gfs2_log_lock(sdp);
 845         sdp->sd_log_head = sdp->sd_log_flush_head;
 846         sdp->sd_log_blks_reserved = 0;
 847         sdp->sd_log_committed_revoke = 0;
 848
 849         spin_lock(&sdp->sd_ail_lock);
 850         if (tr && !list_empty(&tr->tr_ail1_list)) {
 851                 list_add(&tr->tr_list, &sdp->sd_ail1_list);
 852                 tr = NULL;
 853         }
 854         spin_unlock(&sdp->sd_ail_lock);
 855         gfs2_log_unlock(sdp);
 856
 857         if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
 858                 if (!sdp->sd_log_idle) {
 859                         for (;;) {
 860                                 gfs2_ail1_start(sdp);
 861                                 gfs2_ail1_wait(sdp);
 862                                 if (gfs2_ail1_empty(sdp))
 863                                         break;
 864                         }
 865                         atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
 866                         trace_gfs2_log_blocks(sdp, -1);
 867                         log_write_header(sdp, flags);
 868                         sdp->sd_log_head = sdp->sd_log_flush_head;
 869                 }
 870                 if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
 871                              GFS2_LOG_HEAD_FLUSH_FREEZE))
 872                         gfs2_log_shutdown(sdp);
 873                 if (flags & GFS2_LOG_HEAD_FLUSH_FREEZE)
 874                         atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
 875         }
 876
 877         trace_gfs2_log_flush(sdp, 0, flags);
 878         up_write(&sdp->sd_log_flush_lock);
 879
 880         kfree(tr);
 881 }
 882
 883 /**
 884  * gfs2_merge_trans - Merge a new transaction into a cached transaction
 885  * @old: Original transaction to be expanded
 886  * @new: New transaction to be merged
 887  */
 888
 889 static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new)
 890 {
 891         WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags));
 892
 893         old->tr_num_buf_new     += new->tr_num_buf_new;
 894         old->tr_num_databuf_new += new->tr_num_databuf_new;
 895         old->tr_num_buf_rm      += new->tr_num_buf_rm;
 896         old->tr_num_databuf_rm  += new->tr_num_databuf_rm;
 897         old->tr_num_revoke      += new->tr_num_revoke;
 898         old->tr_num_revoke_rm   += new->tr_num_revoke_rm;
 899
 900         list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
 901         list_splice_tail_init(&new->tr_buf, &old->tr_buf);
 902 }
 903
 904 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 905 {
 906         unsigned int reserved;
 907         unsigned int unused;
 908         unsigned int maxres;
 909
 910         gfs2_log_lock(sdp);
 911
 912         if (sdp->sd_log_tr) {
 913                 gfs2_merge_trans(sdp->sd_log_tr, tr);
 914         } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
 915                 gfs2_assert_withdraw(sdp, test_bit(TR_ALLOCED, &tr->tr_flags));
 916                 sdp->sd_log_tr = tr;
 917                 set_bit(TR_ATTACHED, &tr->tr_flags);
 918         }
 919
 920         sdp->sd_log_committed_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 921         reserved = calc_reserved(sdp);
 922         maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
 923         gfs2_assert_withdraw(sdp, maxres >= reserved);
 924         unused = maxres - reserved;
 925         atomic_add(unused, &sdp->sd_log_blks_free);
 926         trace_gfs2_log_blocks(sdp, unused);
 927         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
 928                              sdp->sd_jdesc->jd_blocks);
 929         sdp->sd_log_blks_reserved = reserved;
 930
 931         gfs2_log_unlock(sdp);
 932 }
 933
 934 /**
 935  * gfs2_log_commit - Commit a transaction to the log
 936  * @sdp: the filesystem
 937  * @tr: the transaction
 938  *
 939  * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
 940  * or the total number of used blocks (pinned blocks plus AIL blocks)
 941  * is greater than thresh2.
 942  *
 943  * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
 944  * journal size.
 945  *
 946  * Returns: errno
 947  */
 948
 949 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 950 {
 951         log_refund(sdp, tr);
 952
 953         if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
 954             ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
 955             atomic_read(&sdp->sd_log_thresh2)))
 956                 wake_up(&sdp->sd_logd_waitq);
 957 }
 958
 959 /**
 960  * gfs2_log_shutdown - write a shutdown header into a journal
 961  * @sdp: the filesystem
 962  *
 963  */
 964
 965 static void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 966 {
 967         gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
 968         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 969         gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
 970
 971         sdp->sd_log_flush_head = sdp->sd_log_head;
 972
 973         log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN);
 974
 975         gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
 976         gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 977
 978         sdp->sd_log_head = sdp->sd_log_flush_head;
 979         sdp->sd_log_tail = sdp->sd_log_head;
 980 }
 981
 982 static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
 983 {
 984         return (atomic_read(&sdp->sd_log_pinned) +
 985                 atomic_read(&sdp->sd_log_blks_needed) >=
 986                 atomic_read(&sdp->sd_log_thresh1));
 987 }
 988
 989 static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
 990 {
 991         unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
 992
 993         if (test_and_clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags))
 994                 return 1;
 995
 996         return used_blocks + atomic_read(&sdp->sd_log_blks_needed) >=
 997                 atomic_read(&sdp->sd_log_thresh2);
 998 }
 999
1000 /**
1001  * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
1002  * @sdp: Pointer to GFS2 superblock
1003  *
1004  * Also, periodically check to make sure that we're using the most recent
1005  * journal index.
1006  */
1007
1008 int gfs2_logd(void *data)
1009 {
1010         struct gfs2_sbd *sdp = data;
1011         unsigned long t = 1;
1012         DEFINE_WAIT(wait);
1013         bool did_flush;
1014
1015         while (!kthread_should_stop()) {
1016
1017                 /* Check for errors writing to the journal */
1018                 if (sdp->sd_log_error) {
1019                         gfs2_lm_withdraw(sdp,
1020                                          "GFS2: fsid=%s: error %d: "
1021                                          "withdrawing the file system to "
1022                                          "prevent further damage.\n",
1023                                          sdp->sd_fsname, sdp->sd_log_error);
1024                 }
1025
1026                 did_flush = false;
1027                 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
1028                         gfs2_ail1_empty(sdp);
1029                         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1030                                        GFS2_LFC_LOGD_JFLUSH_REQD);
1031                         did_flush = true;
1032                 }
1033
1034                 if (gfs2_ail_flush_reqd(sdp)) {
1035                         gfs2_ail1_start(sdp);
1036                         gfs2_ail1_wait(sdp);
1037                         gfs2_ail1_empty(sdp);
1038                         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1039                                        GFS2_LFC_LOGD_AIL_FLUSH_REQD);
1040                         did_flush = true;
1041                 }
1042
1043                 if (!gfs2_ail_flush_reqd(sdp) || did_flush)
1044                         wake_up(&sdp->sd_log_waitq);
1045
1046                 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
1047
1048                 try_to_freeze();
1049
1050                 do {
1051                         prepare_to_wait(&sdp->sd_logd_waitq, &wait,
1052                                         TASK_INTERRUPTIBLE);
1053                         if (!gfs2_ail_flush_reqd(sdp) &&
1054                             !gfs2_jrnl_flush_reqd(sdp) &&
1055                             !kthread_should_stop())
1056                                 t = schedule_timeout(t);
1057                 } while(t && !gfs2_ail_flush_reqd(sdp) &&
1058                         !gfs2_jrnl_flush_reqd(sdp) &&
1059                         !kthread_should_stop());
1060                 finish_wait(&sdp->sd_logd_waitq, &wait);
1061         }
1062
1063         return 0;
1064 }
1065