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#include <linux/blkdev.h> 22#include <linux/writeback.h> 23#include <linux/list_sort.h> 24 25#include "gfs2.h" 26#include "incore.h" 27#include "bmap.h" 28#include "glock.h" 29#include "log.h" 30#include "lops.h" 31#include "meta_io.h" 32#include "util.h" 33#include "dir.h" 34#include "trace_gfs2.h" 35 36/** 37 * gfs2_struct2blk - compute stuff 38 * @sdp: the filesystem 39 * @nstruct: the number of structures 40 * @ssize: the size of the structures 41 * 42 * Compute the number of log descriptor blocks needed to hold a certain number 43 * of structures of a certain size. 44 * 45 * Returns: the number of blocks needed (minimum is always 1) 46 */ 47 48unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct, 49 unsigned int ssize) 50{ 51 unsigned int blks; 52 unsigned int first, second; 53 54 blks = 1; 55 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize; 56 57 if (nstruct > first) { 58 second = (sdp->sd_sb.sb_bsize - 59 sizeof(struct gfs2_meta_header)) / ssize; 60 blks += DIV_ROUND_UP(nstruct - first, second); 61 } 62 63 return blks; 64} 65 66/** 67 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters 68 * @mapping: The associated mapping (maybe NULL) 69 * @bd: The gfs2_bufdata to remove 70 * 71 * The ail lock _must_ be held when calling this function 72 * 73 */ 74 75void gfs2_remove_from_ail(struct gfs2_bufdata *bd) 76{ 77 bd->bd_tr = NULL; 78 list_del_init(&bd->bd_ail_st_list); 79 list_del_init(&bd->bd_ail_gl_list); 80 atomic_dec(&bd->bd_gl->gl_ail_count); 81 brelse(bd->bd_bh); 82} 83 84/** 85 * gfs2_ail1_start_one - Start I/O on a part of the AIL 86 * @sdp: the filesystem 87 * @wbc: The writeback control structure 88 * @ai: The ail structure 89 * 90 */ 91 92static int gfs2_ail1_start_one(struct gfs2_sbd *sdp, 93 struct writeback_control *wbc, 94 struct gfs2_trans *tr) 95__releases(&sdp->sd_ail_lock) 96__acquires(&sdp->sd_ail_lock) 97{ 98 struct gfs2_glock *gl = NULL; 99 struct address_space *mapping; 100 struct gfs2_bufdata *bd, *s; 101 struct buffer_head *bh; 102 103 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) { 104 bh = bd->bd_bh; 105 106 gfs2_assert(sdp, bd->bd_tr == tr); 107 108 if (!buffer_busy(bh)) { 109 if (!buffer_uptodate(bh)) 110 gfs2_io_error_bh(sdp, bh); 111 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list); 112 continue; 113 } 114 115 if (!buffer_dirty(bh)) 116 continue; 117 if (gl == bd->bd_gl) 118 continue; 119 gl = bd->bd_gl; 120 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list); 121 mapping = bh->b_page->mapping; 122 if (!mapping) 123 continue; 124 spin_unlock(&sdp->sd_ail_lock); 125 generic_writepages(mapping, wbc); 126 spin_lock(&sdp->sd_ail_lock); 127 if (wbc->nr_to_write <= 0) 128 break; 129 return 1; 130 } 131 132 return 0; 133} 134 135 136/** 137 * gfs2_ail1_flush - start writeback of some ail1 entries 138 * @sdp: The super block 139 * @wbc: The writeback control structure 140 * 141 * Writes back some ail1 entries, according to the limits in the 142 * writeback control structure 143 */ 144 145void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc) 146{ 147 struct list_head *head = &sdp->sd_ail1_list; 148 struct gfs2_trans *tr; 149 struct blk_plug plug; 150 151 trace_gfs2_ail_flush(sdp, wbc, 1); 152 blk_start_plug(&plug); 153 spin_lock(&sdp->sd_ail_lock); 154restart: 155 list_for_each_entry_reverse(tr, head, tr_list) { 156 if (wbc->nr_to_write <= 0) 157 break; 158 if (gfs2_ail1_start_one(sdp, wbc, tr)) 159 goto restart; 160 } 161 spin_unlock(&sdp->sd_ail_lock); 162 blk_finish_plug(&plug); 163 trace_gfs2_ail_flush(sdp, wbc, 0); 164} 165 166/** 167 * gfs2_ail1_start - start writeback of all ail1 entries 168 * @sdp: The superblock 169 */ 170 171static void gfs2_ail1_start(struct gfs2_sbd *sdp) 172{ 173 struct writeback_control wbc = { 174 .sync_mode = WB_SYNC_NONE, 175 .nr_to_write = LONG_MAX, 176 .range_start = 0, 177 .range_end = LLONG_MAX, 178 }; 179 180 return gfs2_ail1_flush(sdp, &wbc); 181} 182 183/** 184 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced 185 * @sdp: the filesystem 186 * @ai: the AIL entry 187 * 188 */ 189 190static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 191{ 192 struct gfs2_bufdata *bd, *s; 193 struct buffer_head *bh; 194 195 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, 196 bd_ail_st_list) { 197 bh = bd->bd_bh; 198 gfs2_assert(sdp, bd->bd_tr == tr); 199 if (buffer_busy(bh)) 200 continue; 201 if (!buffer_uptodate(bh)) 202 gfs2_io_error_bh(sdp, bh); 203 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list); 204 } 205 206} 207 208/** 209 * gfs2_ail1_empty - Try to empty the ail1 lists 210 * @sdp: The superblock 211 * 212 * Tries to empty the ail1 lists, starting with the oldest first 213 */ 214 215static int gfs2_ail1_empty(struct gfs2_sbd *sdp) 216{ 217 struct gfs2_trans *tr, *s; 218 int oldest_tr = 1; 219 int ret; 220 221 spin_lock(&sdp->sd_ail_lock); 222 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) { 223 gfs2_ail1_empty_one(sdp, tr); 224 if (list_empty(&tr->tr_ail1_list) && oldest_tr) 225 list_move(&tr->tr_list, &sdp->sd_ail2_list); 226 else 227 oldest_tr = 0; 228 } 229 ret = list_empty(&sdp->sd_ail1_list); 230 spin_unlock(&sdp->sd_ail_lock); 231 232 return ret; 233} 234 235static void gfs2_ail1_wait(struct gfs2_sbd *sdp) 236{ 237 struct gfs2_trans *tr; 238 struct gfs2_bufdata *bd; 239 struct buffer_head *bh; 240 241 spin_lock(&sdp->sd_ail_lock); 242 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) { 243 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) { 244 bh = bd->bd_bh; 245 if (!buffer_locked(bh)) 246 continue; 247 get_bh(bh); 248 spin_unlock(&sdp->sd_ail_lock); 249 wait_on_buffer(bh); 250 brelse(bh); 251 return; 252 } 253 } 254 spin_unlock(&sdp->sd_ail_lock); 255} 256 257/** 258 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced 259 * @sdp: the filesystem 260 * @ai: the AIL entry 261 * 262 */ 263 264static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 265{ 266 struct list_head *head = &tr->tr_ail2_list; 267 struct gfs2_bufdata *bd; 268 269 while (!list_empty(head)) { 270 bd = list_entry(head->prev, struct gfs2_bufdata, 271 bd_ail_st_list); 272 gfs2_assert(sdp, bd->bd_tr == tr); 273 gfs2_remove_from_ail(bd); 274 } 275} 276 277static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail) 278{ 279 struct gfs2_trans *tr, *safe; 280 unsigned int old_tail = sdp->sd_log_tail; 281 int wrap = (new_tail < old_tail); 282 int a, b, rm; 283 284 spin_lock(&sdp->sd_ail_lock); 285 286 list_for_each_entry_safe(tr, safe, &sdp->sd_ail2_list, tr_list) { 287 a = (old_tail <= tr->tr_first); 288 b = (tr->tr_first < new_tail); 289 rm = (wrap) ? (a || b) : (a && b); 290 if (!rm) 291 continue; 292 293 gfs2_ail2_empty_one(sdp, tr); 294 list_del(&tr->tr_list); 295 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list)); 296 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list)); 297 kfree(tr); 298 } 299 300 spin_unlock(&sdp->sd_ail_lock); 301} 302 303/** 304 * gfs2_log_release - Release a given number of log blocks 305 * @sdp: The GFS2 superblock 306 * @blks: The number of blocks 307 * 308 */ 309 310void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) 311{ 312 313 atomic_add(blks, &sdp->sd_log_blks_free); 314 trace_gfs2_log_blocks(sdp, blks); 315 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= 316 sdp->sd_jdesc->jd_blocks); 317 up_read(&sdp->sd_log_flush_lock); 318} 319 320/** 321 * gfs2_log_reserve - Make a log reservation 322 * @sdp: The GFS2 superblock 323 * @blks: The number of blocks to reserve 324 * 325 * Note that we never give out the last few blocks of the journal. Thats 326 * due to the fact that there is a small number of header blocks 327 * associated with each log flush. The exact number can't be known until 328 * flush time, so we ensure that we have just enough free blocks at all 329 * times to avoid running out during a log flush. 330 * 331 * We no longer flush the log here, instead we wake up logd to do that 332 * for us. To avoid the thundering herd and to ensure that we deal fairly 333 * with queued waiters, we use an exclusive wait. This means that when we 334 * get woken with enough journal space to get our reservation, we need to 335 * wake the next waiter on the list. 336 * 337 * Returns: errno 338 */ 339 340int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks) 341{ 342 int ret = 0; 343 unsigned reserved_blks = 7 * (4096 / sdp->sd_vfs->s_blocksize); 344 unsigned wanted = blks + reserved_blks; 345 DEFINE_WAIT(wait); 346 int did_wait = 0; 347 unsigned int free_blocks; 348 349 if (gfs2_assert_warn(sdp, blks) || 350 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks)) 351 return -EINVAL; 352retry: 353 free_blocks = atomic_read(&sdp->sd_log_blks_free); 354 if (unlikely(free_blocks <= wanted)) { 355 do { 356 prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait, 357 TASK_UNINTERRUPTIBLE); 358 wake_up(&sdp->sd_logd_waitq); 359 did_wait = 1; 360 if (atomic_read(&sdp->sd_log_blks_free) <= wanted) 361 io_schedule(); 362 free_blocks = atomic_read(&sdp->sd_log_blks_free); 363 } while(free_blocks <= wanted); 364 finish_wait(&sdp->sd_log_waitq, &wait); 365 } 366 atomic_inc(&sdp->sd_reserving_log); 367 if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks, 368 free_blocks - blks) != free_blocks) { 369 if (atomic_dec_and_test(&sdp->sd_reserving_log)) 370 wake_up(&sdp->sd_reserving_log_wait); 371 goto retry; 372 } 373 trace_gfs2_log_blocks(sdp, -blks); 374 375 /* 376 * If we waited, then so might others, wake them up _after_ we get 377 * our share of the log. 378 */ 379 if (unlikely(did_wait)) 380 wake_up(&sdp->sd_log_waitq); 381 382 down_read(&sdp->sd_log_flush_lock); 383 if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) { 384 gfs2_log_release(sdp, blks); 385 ret = -EROFS; 386 } 387 if (atomic_dec_and_test(&sdp->sd_reserving_log)) 388 wake_up(&sdp->sd_reserving_log_wait); 389 return ret; 390} 391 392/** 393 * log_distance - Compute distance between two journal blocks 394 * @sdp: The GFS2 superblock 395 * @newer: The most recent journal block of the pair 396 * @older: The older journal block of the pair 397 * 398 * Compute the distance (in the journal direction) between two 399 * blocks in the journal 400 * 401 * Returns: the distance in blocks 402 */ 403 404static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer, 405 unsigned int older) 406{ 407 int dist; 408 409 dist = newer - older; 410 if (dist < 0) 411 dist += sdp->sd_jdesc->jd_blocks; 412 413 return dist; 414} 415 416/** 417 * calc_reserved - Calculate the number of blocks to reserve when 418 * refunding a transaction's unused buffers. 419 * @sdp: The GFS2 superblock 420 * 421 * This is complex. We need to reserve room for all our currently used 422 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and 423 * all our journaled data buffers for journaled files (e.g. files in the 424 * meta_fs like rindex, or files for which chattr +j was done.) 425 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush 426 * will count it as free space (sd_log_blks_free) and corruption will follow. 427 * 428 * We can have metadata bufs and jdata bufs in the same journal. So each 429 * type gets its own log header, for which we need to reserve a block. 430 * In fact, each type has the potential for needing more than one header 431 * in cases where we have more buffers than will fit on a journal page. 432 * Metadata journal entries take up half the space of journaled buffer entries. 433 * Thus, metadata entries have buf_limit (502) and journaled buffers have 434 * databuf_limit (251) before they cause a wrap around. 435 * 436 * Also, we need to reserve blocks for revoke journal entries and one for an 437 * overall header for the lot. 438 * 439 * Returns: the number of blocks reserved 440 */ 441static unsigned int calc_reserved(struct gfs2_sbd *sdp) 442{ 443 unsigned int reserved = 0; 444 unsigned int mbuf; 445 unsigned int dbuf; 446 struct gfs2_trans *tr = sdp->sd_log_tr; 447 448 if (tr) { 449 mbuf = tr->tr_num_buf_new - tr->tr_num_buf_rm; 450 dbuf = tr->tr_num_databuf_new - tr->tr_num_databuf_rm; 451 reserved = mbuf + dbuf; 452 /* Account for header blocks */ 453 reserved += DIV_ROUND_UP(mbuf, buf_limit(sdp)); 454 reserved += DIV_ROUND_UP(dbuf, databuf_limit(sdp)); 455 } 456 457 if (sdp->sd_log_commited_revoke > 0) 458 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke, 459 sizeof(u64)); 460 /* One for the overall header */ 461 if (reserved) 462 reserved++; 463 return reserved; 464} 465 466static unsigned int current_tail(struct gfs2_sbd *sdp) 467{ 468 struct gfs2_trans *tr; 469 unsigned int tail; 470 471 spin_lock(&sdp->sd_ail_lock); 472 473 if (list_empty(&sdp->sd_ail1_list)) { 474 tail = sdp->sd_log_head; 475 } else { 476 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans, 477 tr_list); 478 tail = tr->tr_first; 479 } 480 481 spin_unlock(&sdp->sd_ail_lock); 482 483 return tail; 484} 485 486static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail) 487{ 488 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail); 489 490 ail2_empty(sdp, new_tail); 491 492 atomic_add(dist, &sdp->sd_log_blks_free); 493 trace_gfs2_log_blocks(sdp, dist); 494 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= 495 sdp->sd_jdesc->jd_blocks); 496 497 sdp->sd_log_tail = new_tail; 498} 499 500 501static void log_flush_wait(struct gfs2_sbd *sdp) 502{ 503 DEFINE_WAIT(wait); 504 505 if (atomic_read(&sdp->sd_log_in_flight)) { 506 do { 507 prepare_to_wait(&sdp->sd_log_flush_wait, &wait, 508 TASK_UNINTERRUPTIBLE); 509 if (atomic_read(&sdp->sd_log_in_flight)) 510 io_schedule(); 511 } while(atomic_read(&sdp->sd_log_in_flight)); 512 finish_wait(&sdp->sd_log_flush_wait, &wait); 513 } 514} 515 516static int ip_cmp(void *priv, struct list_head *a, struct list_head *b) 517{ 518 struct gfs2_inode *ipa, *ipb; 519 520 ipa = list_entry(a, struct gfs2_inode, i_ordered); 521 ipb = list_entry(b, struct gfs2_inode, i_ordered); 522 523 if (ipa->i_no_addr < ipb->i_no_addr) 524 return -1; 525 if (ipa->i_no_addr > ipb->i_no_addr) 526 return 1; 527 return 0; 528} 529 530static void gfs2_ordered_write(struct gfs2_sbd *sdp) 531{ 532 struct gfs2_inode *ip; 533 LIST_HEAD(written); 534 535 spin_lock(&sdp->sd_ordered_lock); 536 list_sort(NULL, &sdp->sd_log_le_ordered, &ip_cmp); 537 while (!list_empty(&sdp->sd_log_le_ordered)) { 538 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered); 539 list_move(&ip->i_ordered, &written); 540 if (ip->i_inode.i_mapping->nrpages == 0) 541 continue; 542 spin_unlock(&sdp->sd_ordered_lock); 543 filemap_fdatawrite(ip->i_inode.i_mapping); 544 spin_lock(&sdp->sd_ordered_lock); 545 } 546 list_splice(&written, &sdp->sd_log_le_ordered); 547 spin_unlock(&sdp->sd_ordered_lock); 548} 549 550static void gfs2_ordered_wait(struct gfs2_sbd *sdp) 551{ 552 struct gfs2_inode *ip; 553 554 spin_lock(&sdp->sd_ordered_lock); 555 while (!list_empty(&sdp->sd_log_le_ordered)) { 556 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered); 557 list_del(&ip->i_ordered); 558 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags)); 559 if (ip->i_inode.i_mapping->nrpages == 0) 560 continue; 561 spin_unlock(&sdp->sd_ordered_lock); 562 filemap_fdatawait(ip->i_inode.i_mapping); 563 spin_lock(&sdp->sd_ordered_lock); 564 } 565 spin_unlock(&sdp->sd_ordered_lock); 566} 567 568void gfs2_ordered_del_inode(struct gfs2_inode *ip) 569{ 570 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); 571 572 spin_lock(&sdp->sd_ordered_lock); 573 if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags)) 574 list_del(&ip->i_ordered); 575 spin_unlock(&sdp->sd_ordered_lock); 576} 577 578void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd) 579{ 580 struct buffer_head *bh = bd->bd_bh; 581 struct gfs2_glock *gl = bd->bd_gl; 582 583 bh->b_private = NULL; 584 bd->bd_blkno = bh->b_blocknr; 585 gfs2_remove_from_ail(bd); /* drops ref on bh */ 586 bd->bd_bh = NULL; 587 bd->bd_ops = &gfs2_revoke_lops; 588 sdp->sd_log_num_revoke++; 589 atomic_inc(&gl->gl_revokes); 590 set_bit(GLF_LFLUSH, &gl->gl_flags); 591 list_add(&bd->bd_list, &sdp->sd_log_le_revoke); 592} 593 594void gfs2_write_revokes(struct gfs2_sbd *sdp) 595{ 596 struct gfs2_trans *tr; 597 struct gfs2_bufdata *bd, *tmp; 598 int have_revokes = 0; 599 int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64); 600 601 gfs2_ail1_empty(sdp); 602 spin_lock(&sdp->sd_ail_lock); 603 list_for_each_entry(tr, &sdp->sd_ail1_list, tr_list) { 604 list_for_each_entry(bd, &tr->tr_ail2_list, bd_ail_st_list) { 605 if (list_empty(&bd->bd_list)) { 606 have_revokes = 1; 607 goto done; 608 } 609 } 610 } 611done: 612 spin_unlock(&sdp->sd_ail_lock); 613 if (have_revokes == 0) 614 return; 615 while (sdp->sd_log_num_revoke > max_revokes) 616 max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64); 617 max_revokes -= sdp->sd_log_num_revoke; 618 if (!sdp->sd_log_num_revoke) { 619 atomic_dec(&sdp->sd_log_blks_free); 620 /* If no blocks have been reserved, we need to also 621 * reserve a block for the header */ 622 if (!sdp->sd_log_blks_reserved) 623 atomic_dec(&sdp->sd_log_blks_free); 624 } 625 gfs2_log_lock(sdp); 626 spin_lock(&sdp->sd_ail_lock); 627 list_for_each_entry(tr, &sdp->sd_ail1_list, tr_list) { 628 list_for_each_entry_safe(bd, tmp, &tr->tr_ail2_list, bd_ail_st_list) { 629 if (max_revokes == 0) 630 goto out_of_blocks; 631 if (!list_empty(&bd->bd_list)) 632 continue; 633 gfs2_add_revoke(sdp, bd); 634 max_revokes--; 635 } 636 } 637out_of_blocks: 638 spin_unlock(&sdp->sd_ail_lock); 639 gfs2_log_unlock(sdp); 640 641 if (!sdp->sd_log_num_revoke) { 642 atomic_inc(&sdp->sd_log_blks_free); 643 if (!sdp->sd_log_blks_reserved) 644 atomic_inc(&sdp->sd_log_blks_free); 645 } 646} 647 648/** 649 * log_write_header - Get and initialize a journal header buffer 650 * @sdp: The GFS2 superblock 651 * 652 * Returns: the initialized log buffer descriptor 653 */ 654 655static void log_write_header(struct gfs2_sbd *sdp, u32 flags) 656{ 657 struct gfs2_log_header *lh; 658 unsigned int tail; 659 u32 hash; 660 int rw = WRITE_FLUSH_FUA | REQ_META; 661 struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO); 662 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state); 663 lh = page_address(page); 664 clear_page(lh); 665 666 gfs2_assert_withdraw(sdp, (state != SFS_FROZEN)); 667 668 tail = current_tail(sdp); 669 670 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC); 671 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH); 672 lh->lh_header.__pad0 = cpu_to_be64(0); 673 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH); 674 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid); 675 lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++); 676 lh->lh_flags = cpu_to_be32(flags); 677 lh->lh_tail = cpu_to_be32(tail); 678 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head); 679 hash = gfs2_disk_hash(page_address(page), sizeof(struct gfs2_log_header)); 680 lh->lh_hash = cpu_to_be32(hash); 681 682 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) { 683 gfs2_ordered_wait(sdp); 684 log_flush_wait(sdp); 685 rw = WRITE_SYNC | REQ_META | REQ_PRIO; 686 } 687 688 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head); 689 gfs2_log_write_page(sdp, page); 690 gfs2_log_flush_bio(sdp, rw); 691 log_flush_wait(sdp); 692 693 if (sdp->sd_log_tail != tail) 694 log_pull_tail(sdp, tail); 695} 696 697/** 698 * gfs2_log_flush - flush incore transaction(s) 699 * @sdp: the filesystem 700 * @gl: The glock structure to flush. If NULL, flush the whole incore log 701 * 702 */ 703 704void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, 705 enum gfs2_flush_type type) 706{ 707 struct gfs2_trans *tr; 708 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state); 709 710 down_write(&sdp->sd_log_flush_lock); 711 712 /* Log might have been flushed while we waited for the flush lock */ 713 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) { 714 up_write(&sdp->sd_log_flush_lock); 715 return; 716 } 717 trace_gfs2_log_flush(sdp, 1); 718 719 sdp->sd_log_flush_head = sdp->sd_log_head; 720 sdp->sd_log_flush_wrapped = 0; 721 tr = sdp->sd_log_tr; 722 if (tr) { 723 sdp->sd_log_tr = NULL; 724 INIT_LIST_HEAD(&tr->tr_ail1_list); 725 INIT_LIST_HEAD(&tr->tr_ail2_list); 726 tr->tr_first = sdp->sd_log_flush_head; 727 if (unlikely (state == SFS_FROZEN)) 728 gfs2_assert_withdraw(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new); 729 } 730 731 if (unlikely(state == SFS_FROZEN)) 732 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); 733 gfs2_assert_withdraw(sdp, 734 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke); 735 736 gfs2_ordered_write(sdp); 737 lops_before_commit(sdp, tr); 738 gfs2_log_flush_bio(sdp, WRITE); 739 740 if (sdp->sd_log_head != sdp->sd_log_flush_head) { 741 log_flush_wait(sdp); 742 log_write_header(sdp, 0); 743 } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){ 744 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */ 745 trace_gfs2_log_blocks(sdp, -1); 746 log_write_header(sdp, 0); 747 } 748 lops_after_commit(sdp, tr); 749 750 gfs2_log_lock(sdp); 751 sdp->sd_log_head = sdp->sd_log_flush_head; 752 sdp->sd_log_blks_reserved = 0; 753 sdp->sd_log_commited_revoke = 0; 754 755 spin_lock(&sdp->sd_ail_lock); 756 if (tr && !list_empty(&tr->tr_ail1_list)) { 757 list_add(&tr->tr_list, &sdp->sd_ail1_list); 758 tr = NULL; 759 } 760 spin_unlock(&sdp->sd_ail_lock); 761 gfs2_log_unlock(sdp); 762 763 if (type != NORMAL_FLUSH) { 764 if (!sdp->sd_log_idle) { 765 for (;;) { 766 gfs2_ail1_start(sdp); 767 gfs2_ail1_wait(sdp); 768 if (gfs2_ail1_empty(sdp)) 769 break; 770 } 771 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */ 772 trace_gfs2_log_blocks(sdp, -1); 773 sdp->sd_log_flush_wrapped = 0; 774 log_write_header(sdp, 0); 775 sdp->sd_log_head = sdp->sd_log_flush_head; 776 } 777 if (type == SHUTDOWN_FLUSH || type == FREEZE_FLUSH) 778 gfs2_log_shutdown(sdp); 779 if (type == FREEZE_FLUSH) 780 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN); 781 } 782 783 trace_gfs2_log_flush(sdp, 0); 784 up_write(&sdp->sd_log_flush_lock); 785 786 kfree(tr); 787} 788 789/** 790 * gfs2_merge_trans - Merge a new transaction into a cached transaction 791 * @old: Original transaction to be expanded 792 * @new: New transaction to be merged 793 */ 794 795static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new) 796{ 797 WARN_ON_ONCE(old->tr_attached != 1); 798 799 old->tr_num_buf_new += new->tr_num_buf_new; 800 old->tr_num_databuf_new += new->tr_num_databuf_new; 801 old->tr_num_buf_rm += new->tr_num_buf_rm; 802 old->tr_num_databuf_rm += new->tr_num_databuf_rm; 803 old->tr_num_revoke += new->tr_num_revoke; 804 old->tr_num_revoke_rm += new->tr_num_revoke_rm; 805 806 list_splice_tail_init(&new->tr_databuf, &old->tr_databuf); 807 list_splice_tail_init(&new->tr_buf, &old->tr_buf); 808} 809 810static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 811{ 812 unsigned int reserved; 813 unsigned int unused; 814 unsigned int maxres; 815 816 gfs2_log_lock(sdp); 817 818 if (sdp->sd_log_tr) { 819 gfs2_merge_trans(sdp->sd_log_tr, tr); 820 } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) { 821 gfs2_assert_withdraw(sdp, tr->tr_alloced); 822 sdp->sd_log_tr = tr; 823 tr->tr_attached = 1; 824 } 825 826 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm; 827 reserved = calc_reserved(sdp); 828 maxres = sdp->sd_log_blks_reserved + tr->tr_reserved; 829 gfs2_assert_withdraw(sdp, maxres >= reserved); 830 unused = maxres - reserved; 831 atomic_add(unused, &sdp->sd_log_blks_free); 832 trace_gfs2_log_blocks(sdp, unused); 833 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <= 834 sdp->sd_jdesc->jd_blocks); 835 sdp->sd_log_blks_reserved = reserved; 836 837 gfs2_log_unlock(sdp); 838} 839 840/** 841 * gfs2_log_commit - Commit a transaction to the log 842 * @sdp: the filesystem 843 * @tr: the transaction 844 * 845 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1 846 * or the total number of used blocks (pinned blocks plus AIL blocks) 847 * is greater than thresh2. 848 * 849 * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of 850 * journal size. 851 * 852 * Returns: errno 853 */ 854 855void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr) 856{ 857 log_refund(sdp, tr); 858 859 if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) || 860 ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) > 861 atomic_read(&sdp->sd_log_thresh2))) 862 wake_up(&sdp->sd_logd_waitq); 863} 864 865/** 866 * gfs2_log_shutdown - write a shutdown header into a journal 867 * @sdp: the filesystem 868 * 869 */ 870 871void gfs2_log_shutdown(struct gfs2_sbd *sdp) 872{ 873 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved); 874 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); 875 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list)); 876 877 sdp->sd_log_flush_head = sdp->sd_log_head; 878 sdp->sd_log_flush_wrapped = 0; 879 880 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT); 881 882 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail); 883 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list)); 884 885 sdp->sd_log_head = sdp->sd_log_flush_head; 886 sdp->sd_log_tail = sdp->sd_log_head; 887} 888 889static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp) 890{ 891 return (atomic_read(&sdp->sd_log_pinned) >= atomic_read(&sdp->sd_log_thresh1)); 892} 893 894static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp) 895{ 896 unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free); 897 return used_blocks >= atomic_read(&sdp->sd_log_thresh2); 898} 899 900/** 901 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks 902 * @sdp: Pointer to GFS2 superblock 903 * 904 * Also, periodically check to make sure that we're using the most recent 905 * journal index. 906 */ 907 908int gfs2_logd(void *data) 909{ 910 struct gfs2_sbd *sdp = data; 911 unsigned long t = 1; 912 DEFINE_WAIT(wait); 913 914 while (!kthread_should_stop()) { 915 916 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) { 917 gfs2_ail1_empty(sdp); 918 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH); 919 } 920 921 if (gfs2_ail_flush_reqd(sdp)) { 922 gfs2_ail1_start(sdp); 923 gfs2_ail1_wait(sdp); 924 gfs2_ail1_empty(sdp); 925 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH); 926 } 927 928 if (!gfs2_ail_flush_reqd(sdp)) 929 wake_up(&sdp->sd_log_waitq); 930 931 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ; 932 933 try_to_freeze(); 934 935 do { 936 prepare_to_wait(&sdp->sd_logd_waitq, &wait, 937 TASK_INTERRUPTIBLE); 938 if (!gfs2_ail_flush_reqd(sdp) && 939 !gfs2_jrnl_flush_reqd(sdp) && 940 !kthread_should_stop()) 941 t = schedule_timeout(t); 942 } while(t && !gfs2_ail_flush_reqd(sdp) && 943 !gfs2_jrnl_flush_reqd(sdp) && 944 !kthread_should_stop()); 945 finish_wait(&sdp->sd_logd_waitq, &wait); 946 } 947 948 return 0; 949} 950 951