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 /**
  35  * gfs2_struct2blk - compute stuff
  36  * @sdp: the filesystem
  37  * @nstruct: the number of structures
  38  * @ssize: the size of the structures
  39  *
  40  * Compute the number of log descriptor blocks needed to hold a certain number
  41  * of structures of a certain size.
  42  *
  43  * Returns: the number of blocks needed (minimum is always 1)
  44  */
  45
  46 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
  47                              unsigned int ssize)
  48 {
  49         unsigned int blks;
  50         unsigned int first, second;
  51
  52         blks = 1;
  53         first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
  54
  55         if (nstruct > first) {
  56                 second = (sdp->sd_sb.sb_bsize -
  57                           sizeof(struct gfs2_meta_header)) / ssize;
  58                 blks += DIV_ROUND_UP(nstruct - first, second);
  59         }
  60
  61         return blks;
  62 }
  63
  64 /**
  65  * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
  66  * @mapping: The associated mapping (maybe NULL)
  67  * @bd: The gfs2_bufdata to remove
  68  *
  69  * The ail lock _must_ be held when calling this function
  70  *
  71  */
  72
  73 static void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
  74 {
  75         bd->bd_tr = NULL;
  76         list_del_init(&bd->bd_ail_st_list);
  77         list_del_init(&bd->bd_ail_gl_list);
  78         atomic_dec(&bd->bd_gl->gl_ail_count);
  79         brelse(bd->bd_bh);
  80 }
  81
  82 /**
  83  * gfs2_ail1_start_one - Start I/O on a part of the AIL
  84  * @sdp: the filesystem
  85  * @wbc: The writeback control structure
  86  * @ai: The ail structure
  87  *
  88  */
  89
  90 static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
  91                                struct writeback_control *wbc,
  92                                struct gfs2_trans *tr,
  93                                bool *withdraw)
  94 __releases(&sdp->sd_ail_lock)
  95 __acquires(&sdp->sd_ail_lock)
  96 {
  97         struct gfs2_glock *gl = NULL;
  98         struct address_space *mapping;
  99         struct gfs2_bufdata *bd, *s;
 100         struct buffer_head *bh;
 101
 102         list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
 103                 bh = bd->bd_bh;
 104
 105                 gfs2_assert(sdp, bd->bd_tr == tr);
 106
 107                 if (!buffer_busy(bh)) {
 108                         if (!buffer_uptodate(bh) &&
 109                             !test_and_set_bit(SDF_AIL1_IO_ERROR,
 110                                               &sdp->sd_flags)) {
 111                                 gfs2_io_error_bh(sdp, bh);
 112                                 *withdraw = true;
 113                         }
 114                         list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
 115                         continue;
 116                 }
 117
 118                 if (!buffer_dirty(bh))
 119                         continue;
 120                 if (gl == bd->bd_gl)
 121                         continue;
 122                 gl = bd->bd_gl;
 123                 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
 124                 mapping = bh->b_page->mapping;
 125                 if (!mapping)
 126                         continue;
 127                 spin_unlock(&sdp->sd_ail_lock);
 128                 generic_writepages(mapping, wbc);
 129                 spin_lock(&sdp->sd_ail_lock);
 130                 if (wbc->nr_to_write <= 0)
 131                         break;
 132                 return 1;
 133         }
 134
 135         return 0;
 136 }
 137
 138
 139 /**
 140  * gfs2_ail1_flush - start writeback of some ail1 entries
 141  * @sdp: The super block
 142  * @wbc: The writeback control structure
 143  *
 144  * Writes back some ail1 entries, according to the limits in the
 145  * writeback control structure
 146  */
 147
 148 void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
 149 {
 150         struct list_head *head = &sdp->sd_ail1_list;
 151         struct gfs2_trans *tr;
 152         struct blk_plug plug;
 153         bool withdraw = false;
 154
 155         trace_gfs2_ail_flush(sdp, wbc, 1);
 156         blk_start_plug(&plug);
 157         spin_lock(&sdp->sd_ail_lock);
 158 restart:
 159         list_for_each_entry_reverse(tr, head, tr_list) {
 160                 if (wbc->nr_to_write <= 0)
 161                         break;
 162                 if (gfs2_ail1_start_one(sdp, wbc, tr, &withdraw))
 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_commited_revoke > 0)
 473                 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
 474                                           sizeof(u64));
 475         /* One for the overall header */
 476         if (reserved)
 477                 reserved++;
 478         return reserved;
 479 }
 480
 481 static unsigned int current_tail(struct gfs2_sbd *sdp)
 482 {
 483         struct gfs2_trans *tr;
 484         unsigned int tail;
 485
 486         spin_lock(&sdp->sd_ail_lock);
 487
 488         if (list_empty(&sdp->sd_ail1_list)) {
 489                 tail = sdp->sd_log_head;
 490         } else {
 491                 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans,
 492                                 tr_list);
 493                 tail = tr->tr_first;
 494         }
 495
 496         spin_unlock(&sdp->sd_ail_lock);
 497
 498         return tail;
 499 }
 500
 501 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
 502 {
 503         unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 504
 505         ail2_empty(sdp, new_tail);
 506
 507         atomic_add(dist, &sdp->sd_log_blks_free);
 508         trace_gfs2_log_blocks(sdp, dist);
 509         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
 510                              sdp->sd_jdesc->jd_blocks);
 511
 512         sdp->sd_log_tail = new_tail;
 513 }
 514
 515
 516 static void log_flush_wait(struct gfs2_sbd *sdp)
 517 {
 518         DEFINE_WAIT(wait);
 519
 520         if (atomic_read(&sdp->sd_log_in_flight)) {
 521                 do {
 522                         prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
 523                                         TASK_UNINTERRUPTIBLE);
 524                         if (atomic_read(&sdp->sd_log_in_flight))
 525                                 io_schedule();
 526                 } while(atomic_read(&sdp->sd_log_in_flight));
 527                 finish_wait(&sdp->sd_log_flush_wait, &wait);
 528         }
 529 }
 530
 531 static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
 532 {
 533         struct gfs2_inode *ipa, *ipb;
 534
 535         ipa = list_entry(a, struct gfs2_inode, i_ordered);
 536         ipb = list_entry(b, struct gfs2_inode, i_ordered);
 537
 538         if (ipa->i_no_addr < ipb->i_no_addr)
 539                 return -1;
 540         if (ipa->i_no_addr > ipb->i_no_addr)
 541                 return 1;
 542         return 0;
 543 }
 544
 545 static void gfs2_ordered_write(struct gfs2_sbd *sdp)
 546 {
 547         struct gfs2_inode *ip;
 548         LIST_HEAD(written);
 549
 550         spin_lock(&sdp->sd_ordered_lock);
 551         list_sort(NULL, &sdp->sd_log_ordered, &ip_cmp);
 552         while (!list_empty(&sdp->sd_log_ordered)) {
 553                 ip = list_entry(sdp->sd_log_ordered.next, struct gfs2_inode, i_ordered);
 554                 if (ip->i_inode.i_mapping->nrpages == 0) {
 555                         test_and_clear_bit(GIF_ORDERED, &ip->i_flags);
 556                         list_del(&ip->i_ordered);
 557                         continue;
 558                 }
 559                 list_move(&ip->i_ordered, &written);
 560                 spin_unlock(&sdp->sd_ordered_lock);
 561                 filemap_fdatawrite(ip->i_inode.i_mapping);
 562                 spin_lock(&sdp->sd_ordered_lock);
 563         }
 564         list_splice(&written, &sdp->sd_log_ordered);
 565         spin_unlock(&sdp->sd_ordered_lock);
 566 }
 567
 568 static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
 569 {
 570         struct gfs2_inode *ip;
 571
 572         spin_lock(&sdp->sd_ordered_lock);
 573         while (!list_empty(&sdp->sd_log_ordered)) {
 574                 ip = list_entry(sdp->sd_log_ordered.next, struct gfs2_inode, i_ordered);
 575                 list_del(&ip->i_ordered);
 576                 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags));
 577                 if (ip->i_inode.i_mapping->nrpages == 0)
 578                         continue;
 579                 spin_unlock(&sdp->sd_ordered_lock);
 580                 filemap_fdatawait(ip->i_inode.i_mapping);
 581                 spin_lock(&sdp->sd_ordered_lock);
 582         }
 583         spin_unlock(&sdp->sd_ordered_lock);
 584 }
 585
 586 void gfs2_ordered_del_inode(struct gfs2_inode *ip)
 587 {
 588         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
 589
 590         spin_lock(&sdp->sd_ordered_lock);
 591         if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags))
 592                 list_del(&ip->i_ordered);
 593         spin_unlock(&sdp->sd_ordered_lock);
 594 }
 595
 596 void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
 597 {
 598         struct buffer_head *bh = bd->bd_bh;
 599         struct gfs2_glock *gl = bd->bd_gl;
 600
 601         bh->b_private = NULL;
 602         bd->bd_blkno = bh->b_blocknr;
 603         gfs2_remove_from_ail(bd); /* drops ref on bh */
 604         bd->bd_bh = NULL;
 605         sdp->sd_log_num_revoke++;
 606         if (!test_bit(GLF_REVOKES, &gl->gl_flags)) {
 607                 set_bit(GLF_REVOKES, &gl->gl_flags);
 608                 gfs2_glock_hold(gl);
 609         }
 610         set_bit(GLF_LFLUSH, &gl->gl_flags);
 611         list_add(&bd->bd_list, &sdp->sd_log_revokes);
 612 }
 613
 614 void gfs2_write_revokes(struct gfs2_sbd *sdp)
 615 {
 616         struct gfs2_trans *tr;
 617         struct gfs2_bufdata *bd, *tmp;
 618         int have_revokes = 0;
 619         int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
 620
 621         gfs2_ail1_empty(sdp);
 622         spin_lock(&sdp->sd_ail_lock);
 623         list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
 624                 list_for_each_entry(bd, &tr->tr_ail2_list, bd_ail_st_list) {
 625                         if (list_empty(&bd->bd_list)) {
 626                                 have_revokes = 1;
 627                                 goto done;
 628                         }
 629                 }
 630         }
 631 done:
 632         spin_unlock(&sdp->sd_ail_lock);
 633         if (have_revokes == 0)
 634                 return;
 635         while (sdp->sd_log_num_revoke > max_revokes)
 636                 max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
 637         max_revokes -= sdp->sd_log_num_revoke;
 638         if (!sdp->sd_log_num_revoke) {
 639                 atomic_dec(&sdp->sd_log_blks_free);
 640                 /* If no blocks have been reserved, we need to also
 641                  * reserve a block for the header */
 642                 if (!sdp->sd_log_blks_reserved)
 643                         atomic_dec(&sdp->sd_log_blks_free);
 644         }
 645         gfs2_log_lock(sdp);
 646         spin_lock(&sdp->sd_ail_lock);
 647         list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
 648                 list_for_each_entry_safe(bd, tmp, &tr->tr_ail2_list, bd_ail_st_list) {
 649                         if (max_revokes == 0)
 650                                 goto out_of_blocks;
 651                         if (!list_empty(&bd->bd_list))
 652                                 continue;
 653                         gfs2_add_revoke(sdp, bd);
 654                         max_revokes--;
 655                 }
 656         }
 657 out_of_blocks:
 658         spin_unlock(&sdp->sd_ail_lock);
 659         gfs2_log_unlock(sdp);
 660
 661         if (!sdp->sd_log_num_revoke) {
 662                 atomic_inc(&sdp->sd_log_blks_free);
 663                 if (!sdp->sd_log_blks_reserved)
 664                         atomic_inc(&sdp->sd_log_blks_free);
 665         }
 666 }
 667
 668 /**
 669  * gfs2_write_log_header - Write a journal log header buffer at lblock
 670  * @sdp: The GFS2 superblock
 671  * @jd: journal descriptor of the journal to which we are writing
 672  * @seq: sequence number
 673  * @tail: tail of the log
 674  * @lblock: value for lh_blkno (block number relative to start of journal)
 675  * @flags: log header flags GFS2_LOG_HEAD_*
 676  * @op_flags: flags to pass to the bio
 677  *
 678  * Returns: the initialized log buffer descriptor
 679  */
 680
 681 void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
 682                            u64 seq, u32 tail, u32 lblock, u32 flags,
 683                            int op_flags)
 684 {
 685         struct gfs2_log_header *lh;
 686         u32 hash, crc;
 687         struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
 688         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 689         struct timespec64 tv;
 690         struct super_block *sb = sdp->sd_vfs;
 691         u64 dblock;
 692
 693         lh = page_address(page);
 694         clear_page(lh);
 695
 696         lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 697         lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
 698         lh->lh_header.__pad0 = cpu_to_be64(0);
 699         lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
 700         lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
 701         lh->lh_sequence = cpu_to_be64(seq);
 702         lh->lh_flags = cpu_to_be32(flags);
 703         lh->lh_tail = cpu_to_be32(tail);
 704         lh->lh_blkno = cpu_to_be32(lblock);
 705         hash = ~crc32(~0, lh, LH_V1_SIZE);
 706         lh->lh_hash = cpu_to_be32(hash);
 707
 708         ktime_get_coarse_real_ts64(&tv);
 709         lh->lh_nsec = cpu_to_be32(tv.tv_nsec);
 710         lh->lh_sec = cpu_to_be64(tv.tv_sec);
 711         if (!list_empty(&jd->extent_list))
 712                 dblock = gfs2_log_bmap(sdp);
 713         else {
 714                 int ret = gfs2_lblk_to_dblk(jd->jd_inode, lblock, &dblock);
 715                 if (gfs2_assert_withdraw(sdp, ret == 0))
 716                         return;
 717         }
 718         lh->lh_addr = cpu_to_be64(dblock);
 719         lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr);
 720
 721         /* We may only write local statfs, quota, etc., when writing to our
 722            own journal. The values are left 0 when recovering a journal
 723            different from our own. */
 724         if (!(flags & GFS2_LOG_HEAD_RECOVERY)) {
 725                 lh->lh_statfs_addr =
 726                         cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr);
 727                 lh->lh_quota_addr =
 728                         cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr);
 729
 730                 spin_lock(&sdp->sd_statfs_spin);
 731                 lh->lh_local_total = cpu_to_be64(l_sc->sc_total);
 732                 lh->lh_local_free = cpu_to_be64(l_sc->sc_free);
 733                 lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes);
 734                 spin_unlock(&sdp->sd_statfs_spin);
 735         }
 736
 737         BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE);
 738
 739         crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
 740                      sb->s_blocksize - LH_V1_SIZE - 4);
 741         lh->lh_crc = cpu_to_be32(crc);
 742
 743         gfs2_log_write(sdp, page, sb->s_blocksize, 0, dblock);
 744         gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE | op_flags);
 745         log_flush_wait(sdp);
 746 }
 747
 748 /**
 749  * log_write_header - Get and initialize a journal header buffer
 750  * @sdp: The GFS2 superblock
 751  * @flags: The log header flags, including log header origin
 752  *
 753  * Returns: the initialized log buffer descriptor
 754  */
 755
 756 static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
 757 {
 758         unsigned int tail;
 759         int op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC;
 760         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 761
 762         gfs2_assert_withdraw(sdp, (state != SFS_FROZEN));
 763         tail = current_tail(sdp);
 764
 765         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
 766                 gfs2_ordered_wait(sdp);
 767                 log_flush_wait(sdp);
 768                 op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
 769         }
 770         sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
 771         gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++, tail,
 772                               sdp->sd_log_flush_head, flags, op_flags);
 773
 774         if (sdp->sd_log_tail != tail)
 775                 log_pull_tail(sdp, tail);
 776 }
 777
 778 /**
 779  * gfs2_log_flush - flush incore transaction(s)
 780  * @sdp: the filesystem
 781  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
 782  * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags
 783  *
 784  */
 785
 786 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)
 787 {
 788         struct gfs2_trans *tr;
 789         enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
 790
 791         down_write(&sdp->sd_log_flush_lock);
 792
 793         /* Log might have been flushed while we waited for the flush lock */
 794         if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
 795                 up_write(&sdp->sd_log_flush_lock);
 796                 return;
 797         }
 798         trace_gfs2_log_flush(sdp, 1, flags);
 799
 800         if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN)
 801                 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 802
 803         sdp->sd_log_flush_head = sdp->sd_log_head;
 804         tr = sdp->sd_log_tr;
 805         if (tr) {
 806                 sdp->sd_log_tr = NULL;
 807                 INIT_LIST_HEAD(&tr->tr_ail1_list);
 808                 INIT_LIST_HEAD(&tr->tr_ail2_list);
 809                 tr->tr_first = sdp->sd_log_flush_head;
 810                 if (unlikely (state == SFS_FROZEN))
 811                         gfs2_assert_withdraw(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new);
 812         }
 813
 814         if (unlikely(state == SFS_FROZEN))
 815                 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 816         gfs2_assert_withdraw(sdp,
 817                         sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
 818
 819         gfs2_ordered_write(sdp);
 820         lops_before_commit(sdp, tr);
 821         gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE);
 822
 823         if (sdp->sd_log_head != sdp->sd_log_flush_head) {
 824                 log_flush_wait(sdp);
 825                 log_write_header(sdp, flags);
 826         } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
 827                 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
 828                 trace_gfs2_log_blocks(sdp, -1);
 829                 log_write_header(sdp, flags);
 830         }
 831         lops_after_commit(sdp, tr);
 832
 833         gfs2_log_lock(sdp);
 834         sdp->sd_log_head = sdp->sd_log_flush_head;
 835         sdp->sd_log_blks_reserved = 0;
 836         sdp->sd_log_commited_revoke = 0;
 837
 838         spin_lock(&sdp->sd_ail_lock);
 839         if (tr && !list_empty(&tr->tr_ail1_list)) {
 840                 list_add(&tr->tr_list, &sdp->sd_ail1_list);
 841                 tr = NULL;
 842         }
 843         spin_unlock(&sdp->sd_ail_lock);
 844         gfs2_log_unlock(sdp);
 845
 846         if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
 847                 if (!sdp->sd_log_idle) {
 848                         for (;;) {
 849                                 gfs2_ail1_start(sdp);
 850                                 gfs2_ail1_wait(sdp);
 851                                 if (gfs2_ail1_empty(sdp))
 852                                         break;
 853                         }
 854                         atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
 855                         trace_gfs2_log_blocks(sdp, -1);
 856                         log_write_header(sdp, flags);
 857                         sdp->sd_log_head = sdp->sd_log_flush_head;
 858                 }
 859                 if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
 860                              GFS2_LOG_HEAD_FLUSH_FREEZE))
 861                         gfs2_log_shutdown(sdp);
 862                 if (flags & GFS2_LOG_HEAD_FLUSH_FREEZE)
 863                         atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
 864         }
 865
 866         trace_gfs2_log_flush(sdp, 0, flags);
 867         up_write(&sdp->sd_log_flush_lock);
 868
 869         kfree(tr);
 870 }
 871
 872 /**
 873  * gfs2_merge_trans - Merge a new transaction into a cached transaction
 874  * @old: Original transaction to be expanded
 875  * @new: New transaction to be merged
 876  */
 877
 878 static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new)
 879 {
 880         WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags));
 881
 882         old->tr_num_buf_new     += new->tr_num_buf_new;
 883         old->tr_num_databuf_new += new->tr_num_databuf_new;
 884         old->tr_num_buf_rm      += new->tr_num_buf_rm;
 885         old->tr_num_databuf_rm  += new->tr_num_databuf_rm;
 886         old->tr_num_revoke      += new->tr_num_revoke;
 887         old->tr_num_revoke_rm   += new->tr_num_revoke_rm;
 888
 889         list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
 890         list_splice_tail_init(&new->tr_buf, &old->tr_buf);
 891 }
 892
 893 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 894 {
 895         unsigned int reserved;
 896         unsigned int unused;
 897         unsigned int maxres;
 898
 899         gfs2_log_lock(sdp);
 900
 901         if (sdp->sd_log_tr) {
 902                 gfs2_merge_trans(sdp->sd_log_tr, tr);
 903         } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
 904                 gfs2_assert_withdraw(sdp, test_bit(TR_ALLOCED, &tr->tr_flags));
 905                 sdp->sd_log_tr = tr;
 906                 set_bit(TR_ATTACHED, &tr->tr_flags);
 907         }
 908
 909         sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 910         reserved = calc_reserved(sdp);
 911         maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
 912         gfs2_assert_withdraw(sdp, maxres >= reserved);
 913         unused = maxres - reserved;
 914         atomic_add(unused, &sdp->sd_log_blks_free);
 915         trace_gfs2_log_blocks(sdp, unused);
 916         gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
 917                              sdp->sd_jdesc->jd_blocks);
 918         sdp->sd_log_blks_reserved = reserved;
 919
 920         gfs2_log_unlock(sdp);
 921 }
 922
 923 /**
 924  * gfs2_log_commit - Commit a transaction to the log
 925  * @sdp: the filesystem
 926  * @tr: the transaction
 927  *
 928  * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
 929  * or the total number of used blocks (pinned blocks plus AIL blocks)
 930  * is greater than thresh2.
 931  *
 932  * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
 933  * journal size.
 934  *
 935  * Returns: errno
 936  */
 937
 938 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 939 {
 940         log_refund(sdp, tr);
 941
 942         if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
 943             ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
 944             atomic_read(&sdp->sd_log_thresh2)))
 945                 wake_up(&sdp->sd_logd_waitq);
 946 }
 947
 948 /**
 949  * gfs2_log_shutdown - write a shutdown header into a journal
 950  * @sdp: the filesystem
 951  *
 952  */
 953
 954 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 955 {
 956         gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
 957         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 958         gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
 959
 960         sdp->sd_log_flush_head = sdp->sd_log_head;
 961
 962         log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN);
 963
 964         gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
 965         gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 966
 967         sdp->sd_log_head = sdp->sd_log_flush_head;
 968         sdp->sd_log_tail = sdp->sd_log_head;
 969 }
 970
 971 static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
 972 {
 973         return (atomic_read(&sdp->sd_log_pinned) +
 974                 atomic_read(&sdp->sd_log_blks_needed) >=
 975                 atomic_read(&sdp->sd_log_thresh1));
 976 }
 977
 978 static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
 979 {
 980         unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
 981
 982         if (test_and_clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags))
 983                 return 1;
 984
 985         return used_blocks + atomic_read(&sdp->sd_log_blks_needed) >=
 986                 atomic_read(&sdp->sd_log_thresh2);
 987 }
 988
 989 /**
 990  * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
 991  * @sdp: Pointer to GFS2 superblock
 992  *
 993  * Also, periodically check to make sure that we're using the most recent
 994  * journal index.
 995  */
 996
 997 int gfs2_logd(void *data)
 998 {
 999         struct gfs2_sbd *sdp = data;
1000         unsigned long t = 1;
1001         DEFINE_WAIT(wait);
1002         bool did_flush;
1003
1004         while (!kthread_should_stop()) {
1005
1006                 /* Check for errors writing to the journal */
1007                 if (sdp->sd_log_error) {
1008                         gfs2_lm_withdraw(sdp,
1009                                          "GFS2: fsid=%s: error %d: "
1010                                          "withdrawing the file system to "
1011                                          "prevent further damage.\n",
1012                                          sdp->sd_fsname, sdp->sd_log_error);
1013                 }
1014
1015                 did_flush = false;
1016                 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
1017                         gfs2_ail1_empty(sdp);
1018                         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1019                                        GFS2_LFC_LOGD_JFLUSH_REQD);
1020                         did_flush = true;
1021                 }
1022
1023                 if (gfs2_ail_flush_reqd(sdp)) {
1024                         gfs2_ail1_start(sdp);
1025                         gfs2_ail1_wait(sdp);
1026                         gfs2_ail1_empty(sdp);
1027                         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1028                                        GFS2_LFC_LOGD_AIL_FLUSH_REQD);
1029                         did_flush = true;
1030                 }
1031
1032                 if (!gfs2_ail_flush_reqd(sdp) || did_flush)
1033                         wake_up(&sdp->sd_log_waitq);
1034
1035                 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
1036
1037                 try_to_freeze();
1038
1039                 do {
1040                         prepare_to_wait(&sdp->sd_logd_waitq, &wait,
1041                                         TASK_INTERRUPTIBLE);
1042                         if (!gfs2_ail_flush_reqd(sdp) &&
1043                             !gfs2_jrnl_flush_reqd(sdp) &&
1044                             !kthread_should_stop())
1045                                 t = schedule_timeout(t);
1046                 } while(t && !gfs2_ail_flush_reqd(sdp) &&
1047                         !gfs2_jrnl_flush_reqd(sdp) &&
1048                         !kthread_should_stop());
1049                 finish_wait(&sdp->sd_logd_waitq, &wait);
1050         }
1051
1052         return 0;
1053 }
1054