fs/jfs/jfs_logmgr.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) International Business Machines Corp., 2000-2004
   4  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
   5  */
   6
   7 /*
   8  *      jfs_logmgr.c: log manager
   9  *
  10  * for related information, see transaction manager (jfs_txnmgr.c), and
  11  * recovery manager (jfs_logredo.c).
  12  *
  13  * note: for detail, RTFS.
  14  *
  15  *      log buffer manager:
  16  * special purpose buffer manager supporting log i/o requirements.
  17  * per log serial pageout of logpage
  18  * queuing i/o requests and redrive i/o at iodone
  19  * maintain current logpage buffer
  20  * no caching since append only
  21  * appropriate jfs buffer cache buffers as needed
  22  *
  23  *      group commit:
  24  * transactions which wrote COMMIT records in the same in-memory
  25  * log page during the pageout of previous/current log page(s) are
  26  * committed together by the pageout of the page.
  27  *
  28  *      TBD lazy commit:
  29  * transactions are committed asynchronously when the log page
  30  * containing it COMMIT is paged out when it becomes full;
  31  *
  32  *      serialization:
  33  * . a per log lock serialize log write.
  34  * . a per log lock serialize group commit.
  35  * . a per log lock serialize log open/close;
  36  *
  37  *      TBD log integrity:
  38  * careful-write (ping-pong) of last logpage to recover from crash
  39  * in overwrite.
  40  * detection of split (out-of-order) write of physical sectors
  41  * of last logpage via timestamp at end of each sector
  42  * with its mirror data array at trailer).
  43  *
  44  *      alternatives:
  45  * lsn - 64-bit monotonically increasing integer vs
  46  * 32-bit lspn and page eor.
  47  */
  48
  49 #include <linux/fs.h>
  50 #include <linux/blkdev.h>
  51 #include <linux/interrupt.h>
  52 #include <linux/completion.h>
  53 #include <linux/kthread.h>
  54 #include <linux/buffer_head.h>          /* for sync_blockdev() */
  55 #include <linux/bio.h>
  56 #include <linux/freezer.h>
  57 #include <linux/export.h>
  58 #include <linux/delay.h>
  59 #include <linux/mutex.h>
  60 #include <linux/seq_file.h>
  61 #include <linux/slab.h>
  62 #include "jfs_incore.h"
  63 #include "jfs_filsys.h"
  64 #include "jfs_metapage.h"
  65 #include "jfs_superblock.h"
  66 #include "jfs_txnmgr.h"
  67 #include "jfs_debug.h"
  68
  69
  70 /*
  71  * lbuf's ready to be redriven.  Protected by log_redrive_lock (jfsIO thread)
  72  */
  73 static struct lbuf *log_redrive_list;
  74 static DEFINE_SPINLOCK(log_redrive_lock);
  75
  76
  77 /*
  78  *      log read/write serialization (per log)
  79  */
  80 #define LOG_LOCK_INIT(log)      mutex_init(&(log)->loglock)
  81 #define LOG_LOCK(log)           mutex_lock(&((log)->loglock))
  82 #define LOG_UNLOCK(log)         mutex_unlock(&((log)->loglock))
  83
  84
  85 /*
  86  *      log group commit serialization (per log)
  87  */
  88
  89 #define LOGGC_LOCK_INIT(log)    spin_lock_init(&(log)->gclock)
  90 #define LOGGC_LOCK(log)         spin_lock_irq(&(log)->gclock)
  91 #define LOGGC_UNLOCK(log)       spin_unlock_irq(&(log)->gclock)
  92 #define LOGGC_WAKEUP(tblk)      wake_up_all(&(tblk)->gcwait)
  93
  94 /*
  95  *      log sync serialization (per log)
  96  */
  97 #define LOGSYNC_DELTA(logsize)          min((logsize)/8, 128*LOGPSIZE)
  98 #define LOGSYNC_BARRIER(logsize)        ((logsize)/4)
  99 /*
 100 #define LOGSYNC_DELTA(logsize)          min((logsize)/4, 256*LOGPSIZE)
 101 #define LOGSYNC_BARRIER(logsize)        ((logsize)/2)
 102 */
 103
 104
 105 /*
 106  *      log buffer cache synchronization
 107  */
 108 static DEFINE_SPINLOCK(jfsLCacheLock);
 109
 110 #define LCACHE_LOCK(flags)      spin_lock_irqsave(&jfsLCacheLock, flags)
 111 #define LCACHE_UNLOCK(flags)    spin_unlock_irqrestore(&jfsLCacheLock, flags)
 112
 113 /*
 114  * See __SLEEP_COND in jfs_locks.h
 115  */
 116 #define LCACHE_SLEEP_COND(wq, cond, flags)      \
 117 do {                                            \
 118         if (cond)                               \
 119                 break;                          \
 120         __SLEEP_COND(wq, cond, LCACHE_LOCK(flags), LCACHE_UNLOCK(flags)); \
 121 } while (0)
 122
 123 #define LCACHE_WAKEUP(event)    wake_up(event)
 124
 125
 126 /*
 127  *      lbuf buffer cache (lCache) control
 128  */
 129 /* log buffer manager pageout control (cumulative, inclusive) */
 130 #define lbmREAD         0x0001
 131 #define lbmWRITE        0x0002  /* enqueue at tail of write queue;
 132                                  * init pageout if at head of queue;
 133                                  */
 134 #define lbmRELEASE      0x0004  /* remove from write queue
 135                                  * at completion of pageout;
 136                                  * do not free/recycle it yet:
 137                                  * caller will free it;
 138                                  */
 139 #define lbmSYNC         0x0008  /* do not return to freelist
 140                                  * when removed from write queue;
 141                                  */
 142 #define lbmFREE         0x0010  /* return to freelist
 143                                  * at completion of pageout;
 144                                  * the buffer may be recycled;
 145                                  */
 146 #define lbmDONE         0x0020
 147 #define lbmERROR        0x0040
 148 #define lbmGC           0x0080  /* lbmIODone to perform post-GC processing
 149                                  * of log page
 150                                  */
 151 #define lbmDIRECT       0x0100
 152
 153 /*
 154  * Global list of active external journals
 155  */
 156 static LIST_HEAD(jfs_external_logs);
 157 static struct jfs_log *dummy_log;
 158 static DEFINE_MUTEX(jfs_log_mutex);
 159
 160 /*
 161  * forward references
 162  */
 163 static int lmWriteRecord(struct jfs_log * log, struct tblock * tblk,
 164                          struct lrd * lrd, struct tlock * tlck);
 165
 166 static int lmNextPage(struct jfs_log * log);
 167 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
 168                            int activate);
 169
 170 static int open_inline_log(struct super_block *sb);
 171 static int open_dummy_log(struct super_block *sb);
 172 static int lbmLogInit(struct jfs_log * log);
 173 static void lbmLogShutdown(struct jfs_log * log);
 174 static struct lbuf *lbmAllocate(struct jfs_log * log, int);
 175 static void lbmFree(struct lbuf * bp);
 176 static void lbmfree(struct lbuf * bp);
 177 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp);
 178 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag, int cant_block);
 179 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag);
 180 static int lbmIOWait(struct lbuf * bp, int flag);
 181 static bio_end_io_t lbmIODone;
 182 static void lbmStartIO(struct lbuf * bp);
 183 static void lmGCwrite(struct jfs_log * log, int cant_block);
 184 static int lmLogSync(struct jfs_log * log, int hard_sync);
 185
 186
 187
 188 /*
 189  *      statistics
 190  */
 191 #ifdef CONFIG_JFS_STATISTICS
 192 static struct lmStat {
 193         uint commit;            /* # of commit */
 194         uint pagedone;          /* # of page written */
 195         uint submitted;         /* # of pages submitted */
 196         uint full_page;         /* # of full pages submitted */
 197         uint partial_page;      /* # of partial pages submitted */
 198 } lmStat;
 199 #endif
 200
 201 static void write_special_inodes(struct jfs_log *log,
 202                                  int (*writer)(struct address_space *))
 203 {
 204         struct jfs_sb_info *sbi;
 205
 206         list_for_each_entry(sbi, &log->sb_list, log_list) {
 207                 writer(sbi->ipbmap->i_mapping);
 208                 writer(sbi->ipimap->i_mapping);
 209                 writer(sbi->direct_inode->i_mapping);
 210         }
 211 }
 212
 213 /*
 214  * NAME:        lmLog()
 215  *
 216  * FUNCTION:    write a log record;
 217  *
 218  * PARAMETER:
 219  *
 220  * RETURN:      lsn - offset to the next log record to write (end-of-log);
 221  *              -1  - error;
 222  *
 223  * note: todo: log error handler
 224  */
 225 int lmLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
 226           struct tlock * tlck)
 227 {
 228         int lsn;
 229         int diffp, difft;
 230         struct metapage *mp = NULL;
 231         unsigned long flags;
 232
 233         jfs_info("lmLog: log:0x%p tblk:0x%p, lrd:0x%p tlck:0x%p",
 234                  log, tblk, lrd, tlck);
 235
 236         LOG_LOCK(log);
 237
 238         /* log by (out-of-transaction) JFS ? */
 239         if (tblk == NULL)
 240                 goto writeRecord;
 241
 242         /* log from page ? */
 243         if (tlck == NULL ||
 244             tlck->type & tlckBTROOT || (mp = tlck->mp) == NULL)
 245                 goto writeRecord;
 246
 247         /*
 248          *      initialize/update page/transaction recovery lsn
 249          */
 250         lsn = log->lsn;
 251
 252         LOGSYNC_LOCK(log, flags);
 253
 254         /*
 255          * initialize page lsn if first log write of the page
 256          */
 257         if (mp->lsn == 0) {
 258                 mp->log = log;
 259                 mp->lsn = lsn;
 260                 log->count++;
 261
 262                 /* insert page at tail of logsynclist */
 263                 list_add_tail(&mp->synclist, &log->synclist);
 264         }
 265
 266         /*
 267          *      initialize/update lsn of tblock of the page
 268          *
 269          * transaction inherits oldest lsn of pages associated
 270          * with allocation/deallocation of resources (their
 271          * log records are used to reconstruct allocation map
 272          * at recovery time: inode for inode allocation map,
 273          * B+-tree index of extent descriptors for block
 274          * allocation map);
 275          * allocation map pages inherit transaction lsn at
 276          * commit time to allow forwarding log syncpt past log
 277          * records associated with allocation/deallocation of
 278          * resources only after persistent map of these map pages
 279          * have been updated and propagated to home.
 280          */
 281         /*
 282          * initialize transaction lsn:
 283          */
 284         if (tblk->lsn == 0) {
 285                 /* inherit lsn of its first page logged */
 286                 tblk->lsn = mp->lsn;
 287                 log->count++;
 288
 289                 /* insert tblock after the page on logsynclist */
 290                 list_add(&tblk->synclist, &mp->synclist);
 291         }
 292         /*
 293          * update transaction lsn:
 294          */
 295         else {
 296                 /* inherit oldest/smallest lsn of page */
 297                 logdiff(diffp, mp->lsn, log);
 298                 logdiff(difft, tblk->lsn, log);
 299                 if (diffp < difft) {
 300                         /* update tblock lsn with page lsn */
 301                         tblk->lsn = mp->lsn;
 302
 303                         /* move tblock after page on logsynclist */
 304                         list_move(&tblk->synclist, &mp->synclist);
 305                 }
 306         }
 307
 308         LOGSYNC_UNLOCK(log, flags);
 309
 310         /*
 311          *      write the log record
 312          */
 313       writeRecord:
 314         lsn = lmWriteRecord(log, tblk, lrd, tlck);
 315
 316         /*
 317          * forward log syncpt if log reached next syncpt trigger
 318          */
 319         logdiff(diffp, lsn, log);
 320         if (diffp >= log->nextsync)
 321                 lsn = lmLogSync(log, 0);
 322
 323         /* update end-of-log lsn */
 324         log->lsn = lsn;
 325
 326         LOG_UNLOCK(log);
 327
 328         /* return end-of-log address */
 329         return lsn;
 330 }
 331
 332 /*
 333  * NAME:        lmWriteRecord()
 334  *
 335  * FUNCTION:    move the log record to current log page
 336  *
 337  * PARAMETER:   cd      - commit descriptor
 338  *
 339  * RETURN:      end-of-log address
 340  *
 341  * serialization: LOG_LOCK() held on entry/exit
 342  */
 343 static int
 344 lmWriteRecord(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
 345               struct tlock * tlck)
 346 {
 347         int lsn = 0;            /* end-of-log address */
 348         struct lbuf *bp;        /* dst log page buffer */
 349         struct logpage *lp;     /* dst log page */
 350         caddr_t dst;            /* destination address in log page */
 351         int dstoffset;          /* end-of-log offset in log page */
 352         int freespace;          /* free space in log page */
 353         caddr_t p;              /* src meta-data page */
 354         caddr_t src;
 355         int srclen;
 356         int nbytes;             /* number of bytes to move */
 357         int i;
 358         int len;
 359         struct linelock *linelock;
 360         struct lv *lv;
 361         struct lvd *lvd;
 362         int l2linesize;
 363
 364         len = 0;
 365
 366         /* retrieve destination log page to write */
 367         bp = (struct lbuf *) log->bp;
 368         lp = (struct logpage *) bp->l_ldata;
 369         dstoffset = log->eor;
 370
 371         /* any log data to write ? */
 372         if (tlck == NULL)
 373                 goto moveLrd;
 374
 375         /*
 376          *      move log record data
 377          */
 378         /* retrieve source meta-data page to log */
 379         if (tlck->flag & tlckPAGELOCK) {
 380                 p = (caddr_t) (tlck->mp->data);
 381                 linelock = (struct linelock *) & tlck->lock;
 382         }
 383         /* retrieve source in-memory inode to log */
 384         else if (tlck->flag & tlckINODELOCK) {
 385                 if (tlck->type & tlckDTREE)
 386                         p = (caddr_t) &JFS_IP(tlck->ip)->i_dtroot;
 387                 else
 388                         p = (caddr_t) &JFS_IP(tlck->ip)->i_xtroot;
 389                 linelock = (struct linelock *) & tlck->lock;
 390         }
 391 #ifdef  _JFS_WIP
 392         else if (tlck->flag & tlckINLINELOCK) {
 393
 394                 inlinelock = (struct inlinelock *) & tlck;
 395                 p = (caddr_t) & inlinelock->pxd;
 396                 linelock = (struct linelock *) & tlck;
 397         }
 398 #endif                          /* _JFS_WIP */
 399         else {
 400                 jfs_err("lmWriteRecord: UFO tlck:0x%p", tlck);
 401                 return 0;       /* Probably should trap */
 402         }
 403         l2linesize = linelock->l2linesize;
 404
 405       moveData:
 406         ASSERT(linelock->index <= linelock->maxcnt);
 407
 408         lv = linelock->lv;
 409         for (i = 0; i < linelock->index; i++, lv++) {
 410                 if (lv->length == 0)
 411                         continue;
 412
 413                 /* is page full ? */
 414                 if (dstoffset >= LOGPSIZE - LOGPTLRSIZE) {
 415                         /* page become full: move on to next page */
 416                         lmNextPage(log);
 417
 418                         bp = log->bp;
 419                         lp = (struct logpage *) bp->l_ldata;
 420                         dstoffset = LOGPHDRSIZE;
 421                 }
 422
 423                 /*
 424                  * move log vector data
 425                  */
 426                 src = (u8 *) p + (lv->offset << l2linesize);
 427                 srclen = lv->length << l2linesize;
 428                 len += srclen;
 429                 while (srclen > 0) {
 430                         freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
 431                         nbytes = min(freespace, srclen);
 432                         dst = (caddr_t) lp + dstoffset;
 433                         memcpy(dst, src, nbytes);
 434                         dstoffset += nbytes;
 435
 436                         /* is page not full ? */
 437                         if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
 438                                 break;
 439
 440                         /* page become full: move on to next page */
 441                         lmNextPage(log);
 442
 443                         bp = (struct lbuf *) log->bp;
 444                         lp = (struct logpage *) bp->l_ldata;
 445                         dstoffset = LOGPHDRSIZE;
 446
 447                         srclen -= nbytes;
 448                         src += nbytes;
 449                 }
 450
 451                 /*
 452                  * move log vector descriptor
 453                  */
 454                 len += 4;
 455                 lvd = (struct lvd *) ((caddr_t) lp + dstoffset);
 456                 lvd->offset = cpu_to_le16(lv->offset);
 457                 lvd->length = cpu_to_le16(lv->length);
 458                 dstoffset += 4;
 459                 jfs_info("lmWriteRecord: lv offset:%d length:%d",
 460                          lv->offset, lv->length);
 461         }
 462
 463         if ((i = linelock->next)) {
 464                 linelock = (struct linelock *) lid_to_tlock(i);
 465                 goto moveData;
 466         }
 467
 468         /*
 469          *      move log record descriptor
 470          */
 471       moveLrd:
 472         lrd->length = cpu_to_le16(len);
 473
 474         src = (caddr_t) lrd;
 475         srclen = LOGRDSIZE;
 476
 477         while (srclen > 0) {
 478                 freespace = (LOGPSIZE - LOGPTLRSIZE) - dstoffset;
 479                 nbytes = min(freespace, srclen);
 480                 dst = (caddr_t) lp + dstoffset;
 481                 memcpy(dst, src, nbytes);
 482
 483                 dstoffset += nbytes;
 484                 srclen -= nbytes;
 485
 486                 /* are there more to move than freespace of page ? */
 487                 if (srclen)
 488                         goto pageFull;
 489
 490                 /*
 491                  * end of log record descriptor
 492                  */
 493
 494                 /* update last log record eor */
 495                 log->eor = dstoffset;
 496                 bp->l_eor = dstoffset;
 497                 lsn = (log->page << L2LOGPSIZE) + dstoffset;
 498
 499                 if (lrd->type & cpu_to_le16(LOG_COMMIT)) {
 500                         tblk->clsn = lsn;
 501                         jfs_info("wr: tclsn:0x%x, beor:0x%x", tblk->clsn,
 502                                  bp->l_eor);
 503
 504                         INCREMENT(lmStat.commit);       /* # of commit */
 505
 506                         /*
 507                          * enqueue tblock for group commit:
 508                          *
 509                          * enqueue tblock of non-trivial/synchronous COMMIT
 510                          * at tail of group commit queue
 511                          * (trivial/asynchronous COMMITs are ignored by
 512                          * group commit.)
 513                          */
 514                         LOGGC_LOCK(log);
 515
 516                         /* init tblock gc state */
 517                         tblk->flag = tblkGC_QUEUE;
 518                         tblk->bp = log->bp;
 519                         tblk->pn = log->page;
 520                         tblk->eor = log->eor;
 521
 522                         /* enqueue transaction to commit queue */
 523                         list_add_tail(&tblk->cqueue, &log->cqueue);
 524
 525                         LOGGC_UNLOCK(log);
 526                 }
 527
 528                 jfs_info("lmWriteRecord: lrd:0x%04x bp:0x%p pn:%d eor:0x%x",
 529                         le16_to_cpu(lrd->type), log->bp, log->page, dstoffset);
 530
 531                 /* page not full ? */
 532                 if (dstoffset < LOGPSIZE - LOGPTLRSIZE)
 533                         return lsn;
 534
 535               pageFull:
 536                 /* page become full: move on to next page */
 537                 lmNextPage(log);
 538
 539                 bp = (struct lbuf *) log->bp;
 540                 lp = (struct logpage *) bp->l_ldata;
 541                 dstoffset = LOGPHDRSIZE;
 542                 src += nbytes;
 543         }
 544
 545         return lsn;
 546 }
 547
 548
 549 /*
 550  * NAME:        lmNextPage()
 551  *
 552  * FUNCTION:    write current page and allocate next page.
 553  *
 554  * PARAMETER:   log
 555  *
 556  * RETURN:      0
 557  *
 558  * serialization: LOG_LOCK() held on entry/exit
 559  */
 560 static int lmNextPage(struct jfs_log * log)
 561 {
 562         struct logpage *lp;
 563         int lspn;               /* log sequence page number */
 564         int pn;                 /* current page number */
 565         struct lbuf *bp;
 566         struct lbuf *nextbp;
 567         struct tblock *tblk;
 568
 569         /* get current log page number and log sequence page number */
 570         pn = log->page;
 571         bp = log->bp;
 572         lp = (struct logpage *) bp->l_ldata;
 573         lspn = le32_to_cpu(lp->h.page);
 574
 575         LOGGC_LOCK(log);
 576
 577         /*
 578          *      write or queue the full page at the tail of write queue
 579          */
 580         /* get the tail tblk on commit queue */
 581         if (list_empty(&log->cqueue))
 582                 tblk = NULL;
 583         else
 584                 tblk = list_entry(log->cqueue.prev, struct tblock, cqueue);
 585
 586         /* every tblk who has COMMIT record on the current page,
 587          * and has not been committed, must be on commit queue
 588          * since tblk is queued at commit queueu at the time
 589          * of writing its COMMIT record on the page before
 590          * page becomes full (even though the tblk thread
 591          * who wrote COMMIT record may have been suspended
 592          * currently);
 593          */
 594
 595         /* is page bound with outstanding tail tblk ? */
 596         if (tblk && tblk->pn == pn) {
 597                 /* mark tblk for end-of-page */
 598                 tblk->flag |= tblkGC_EOP;
 599
 600                 if (log->cflag & logGC_PAGEOUT) {
 601                         /* if page is not already on write queue,
 602                          * just enqueue (no lbmWRITE to prevent redrive)
 603                          * buffer to wqueue to ensure correct serial order
 604                          * of the pages since log pages will be added
 605                          * continuously
 606                          */
 607                         if (bp->l_wqnext == NULL)
 608                                 lbmWrite(log, bp, 0, 0);
 609                 } else {
 610                         /*
 611                          * No current GC leader, initiate group commit
 612                          */
 613                         log->cflag |= logGC_PAGEOUT;
 614                         lmGCwrite(log, 0);
 615                 }
 616         }
 617         /* page is not bound with outstanding tblk:
 618          * init write or mark it to be redriven (lbmWRITE)
 619          */
 620         else {
 621                 /* finalize the page */
 622                 bp->l_ceor = bp->l_eor;
 623                 lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
 624                 lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE, 0);
 625         }
 626         LOGGC_UNLOCK(log);
 627
 628         /*
 629          *      allocate/initialize next page
 630          */
 631         /* if log wraps, the first data page of log is 2
 632          * (0 never used, 1 is superblock).
 633          */
 634         log->page = (pn == log->size - 1) ? 2 : pn + 1;
 635         log->eor = LOGPHDRSIZE; /* ? valid page empty/full at logRedo() */
 636
 637         /* allocate/initialize next log page buffer */
 638         nextbp = lbmAllocate(log, log->page);
 639         nextbp->l_eor = log->eor;
 640         log->bp = nextbp;
 641
 642         /* initialize next log page */
 643         lp = (struct logpage *) nextbp->l_ldata;
 644         lp->h.page = lp->t.page = cpu_to_le32(lspn + 1);
 645         lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
 646
 647         return 0;
 648 }
 649
 650
 651 /*
 652  * NAME:        lmGroupCommit()
 653  *
 654  * FUNCTION:    group commit
 655  *      initiate pageout of the pages with COMMIT in the order of
 656  *      page number - redrive pageout of the page at the head of
 657  *      pageout queue until full page has been written.
 658  *
 659  * RETURN:
 660  *
 661  * NOTE:
 662  *      LOGGC_LOCK serializes log group commit queue, and
 663  *      transaction blocks on the commit queue.
 664  *      N.B. LOG_LOCK is NOT held during lmGroupCommit().
 665  */
 666 int lmGroupCommit(struct jfs_log * log, struct tblock * tblk)
 667 {
 668         int rc = 0;
 669
 670         LOGGC_LOCK(log);
 671
 672         /* group committed already ? */
 673         if (tblk->flag & tblkGC_COMMITTED) {
 674                 if (tblk->flag & tblkGC_ERROR)
 675                         rc = -EIO;
 676
 677                 LOGGC_UNLOCK(log);
 678                 return rc;
 679         }
 680         jfs_info("lmGroup Commit: tblk = 0x%p, gcrtc = %d", tblk, log->gcrtc);
 681
 682         if (tblk->xflag & COMMIT_LAZY)
 683                 tblk->flag |= tblkGC_LAZY;
 684
 685         if ((!(log->cflag & logGC_PAGEOUT)) && (!list_empty(&log->cqueue)) &&
 686             (!(tblk->xflag & COMMIT_LAZY) || test_bit(log_FLUSH, &log->flag)
 687              || jfs_tlocks_low)) {
 688                 /*
 689                  * No pageout in progress
 690                  *
 691                  * start group commit as its group leader.
 692                  */
 693                 log->cflag |= logGC_PAGEOUT;
 694
 695                 lmGCwrite(log, 0);
 696         }
 697
 698         if (tblk->xflag & COMMIT_LAZY) {
 699                 /*
 700                  * Lazy transactions can leave now
 701                  */
 702                 LOGGC_UNLOCK(log);
 703                 return 0;
 704         }
 705
 706         /* lmGCwrite gives up LOGGC_LOCK, check again */
 707
 708         if (tblk->flag & tblkGC_COMMITTED) {
 709                 if (tblk->flag & tblkGC_ERROR)
 710                         rc = -EIO;
 711
 712                 LOGGC_UNLOCK(log);
 713                 return rc;
 714         }
 715
 716         /* upcount transaction waiting for completion
 717          */
 718         log->gcrtc++;
 719         tblk->flag |= tblkGC_READY;
 720
 721         __SLEEP_COND(tblk->gcwait, (tblk->flag & tblkGC_COMMITTED),
 722                      LOGGC_LOCK(log), LOGGC_UNLOCK(log));
 723
 724         /* removed from commit queue */
 725         if (tblk->flag & tblkGC_ERROR)
 726                 rc = -EIO;
 727
 728         LOGGC_UNLOCK(log);
 729         return rc;
 730 }
 731
 732 /*
 733  * NAME:        lmGCwrite()
 734  *
 735  * FUNCTION:    group commit write
 736  *      initiate write of log page, building a group of all transactions
 737  *      with commit records on that page.
 738  *
 739  * RETURN:      None
 740  *
 741  * NOTE:
 742  *      LOGGC_LOCK must be held by caller.
 743  *      N.B. LOG_LOCK is NOT held during lmGroupCommit().
 744  */
 745 static void lmGCwrite(struct jfs_log * log, int cant_write)
 746 {
 747         struct lbuf *bp;
 748         struct logpage *lp;
 749         int gcpn;               /* group commit page number */
 750         struct tblock *tblk;
 751         struct tblock *xtblk = NULL;
 752
 753         /*
 754          * build the commit group of a log page
 755          *
 756          * scan commit queue and make a commit group of all
 757          * transactions with COMMIT records on the same log page.
 758          */
 759         /* get the head tblk on the commit queue */
 760         gcpn = list_entry(log->cqueue.next, struct tblock, cqueue)->pn;
 761
 762         list_for_each_entry(tblk, &log->cqueue, cqueue) {
 763                 if (tblk->pn != gcpn)
 764                         break;
 765
 766                 xtblk = tblk;
 767
 768                 /* state transition: (QUEUE, READY) -> COMMIT */
 769                 tblk->flag |= tblkGC_COMMIT;
 770         }
 771         tblk = xtblk;           /* last tblk of the page */
 772
 773         /*
 774          * pageout to commit transactions on the log page.
 775          */
 776         bp = (struct lbuf *) tblk->bp;
 777         lp = (struct logpage *) bp->l_ldata;
 778         /* is page already full ? */
 779         if (tblk->flag & tblkGC_EOP) {
 780                 /* mark page to free at end of group commit of the page */
 781                 tblk->flag &= ~tblkGC_EOP;
 782                 tblk->flag |= tblkGC_FREE;
 783                 bp->l_ceor = bp->l_eor;
 784                 lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
 785                 lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmGC,
 786                          cant_write);
 787                 INCREMENT(lmStat.full_page);
 788         }
 789         /* page is not yet full */
 790         else {
 791                 bp->l_ceor = tblk->eor; /* ? bp->l_ceor = bp->l_eor; */
 792                 lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_ceor);
 793                 lbmWrite(log, bp, lbmWRITE | lbmGC, cant_write);
 794                 INCREMENT(lmStat.partial_page);
 795         }
 796 }
 797
 798 /*
 799  * NAME:        lmPostGC()
 800  *
 801  * FUNCTION:    group commit post-processing
 802  *      Processes transactions after their commit records have been written
 803  *      to disk, redriving log I/O if necessary.
 804  *
 805  * RETURN:      None
 806  *
 807  * NOTE:
 808  *      This routine is called a interrupt time by lbmIODone
 809  */
 810 static void lmPostGC(struct lbuf * bp)
 811 {
 812         unsigned long flags;
 813         struct jfs_log *log = bp->l_log;
 814         struct logpage *lp;
 815         struct tblock *tblk, *temp;
 816
 817         //LOGGC_LOCK(log);
 818         spin_lock_irqsave(&log->gclock, flags);
 819         /*
 820          * current pageout of group commit completed.
 821          *
 822          * remove/wakeup transactions from commit queue who were
 823          * group committed with the current log page
 824          */
 825         list_for_each_entry_safe(tblk, temp, &log->cqueue, cqueue) {
 826                 if (!(tblk->flag & tblkGC_COMMIT))
 827                         break;
 828                 /* if transaction was marked GC_COMMIT then
 829                  * it has been shipped in the current pageout
 830                  * and made it to disk - it is committed.
 831                  */
 832
 833                 if (bp->l_flag & lbmERROR)
 834                         tblk->flag |= tblkGC_ERROR;
 835
 836                 /* remove it from the commit queue */
 837                 list_del(&tblk->cqueue);
 838                 tblk->flag &= ~tblkGC_QUEUE;
 839
 840                 if (tblk == log->flush_tblk) {
 841                         /* we can stop flushing the log now */
 842                         clear_bit(log_FLUSH, &log->flag);
 843                         log->flush_tblk = NULL;
 844                 }
 845
 846                 jfs_info("lmPostGC: tblk = 0x%p, flag = 0x%x", tblk,
 847                          tblk->flag);
 848
 849                 if (!(tblk->xflag & COMMIT_FORCE))
 850                         /*
 851                          * Hand tblk over to lazy commit thread
 852                          */
 853                         txLazyUnlock(tblk);
 854                 else {
 855                         /* state transition: COMMIT -> COMMITTED */
 856                         tblk->flag |= tblkGC_COMMITTED;
 857
 858                         if (tblk->flag & tblkGC_READY)
 859                                 log->gcrtc--;
 860
 861                         LOGGC_WAKEUP(tblk);
 862                 }
 863
 864                 /* was page full before pageout ?
 865                  * (and this is the last tblk bound with the page)
 866                  */
 867                 if (tblk->flag & tblkGC_FREE)
 868                         lbmFree(bp);
 869                 /* did page become full after pageout ?
 870                  * (and this is the last tblk bound with the page)
 871                  */
 872                 else if (tblk->flag & tblkGC_EOP) {
 873                         /* finalize the page */
 874                         lp = (struct logpage *) bp->l_ldata;
 875                         bp->l_ceor = bp->l_eor;
 876                         lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
 877                         jfs_info("lmPostGC: calling lbmWrite");
 878                         lbmWrite(log, bp, lbmWRITE | lbmRELEASE | lbmFREE,
 879                                  1);
 880                 }
 881
 882         }
 883
 884         /* are there any transactions who have entered lnGroupCommit()
 885          * (whose COMMITs are after that of the last log page written.
 886          * They are waiting for new group commit (above at (SLEEP 1))
 887          * or lazy transactions are on a full (queued) log page,
 888          * select the latest ready transaction as new group leader and
 889          * wake her up to lead her group.
 890          */
 891         if ((!list_empty(&log->cqueue)) &&
 892             ((log->gcrtc > 0) || (tblk->bp->l_wqnext != NULL) ||
 893              test_bit(log_FLUSH, &log->flag) || jfs_tlocks_low))
 894                 /*
 895                  * Call lmGCwrite with new group leader
 896                  */
 897                 lmGCwrite(log, 1);
 898
 899         /* no transaction are ready yet (transactions are only just
 900          * queued (GC_QUEUE) and not entered for group commit yet).
 901          * the first transaction entering group commit
 902          * will elect herself as new group leader.
 903          */
 904         else
 905                 log->cflag &= ~logGC_PAGEOUT;
 906
 907         //LOGGC_UNLOCK(log);
 908         spin_unlock_irqrestore(&log->gclock, flags);
 909         return;
 910 }
 911
 912 /*
 913  * NAME:        lmLogSync()
 914  *
 915  * FUNCTION:    write log SYNCPT record for specified log
 916  *      if new sync address is available
 917  *      (normally the case if sync() is executed by back-ground
 918  *      process).
 919  *      calculate new value of i_nextsync which determines when
 920  *      this code is called again.
 921  *
 922  * PARAMETERS:  log     - log structure
 923  *              hard_sync - 1 to force all metadata to be written
 924  *
 925  * RETURN:      0
 926  *
 927  * serialization: LOG_LOCK() held on entry/exit
 928  */
 929 static int lmLogSync(struct jfs_log * log, int hard_sync)
 930 {
 931         int logsize;
 932         int written;            /* written since last syncpt */
 933         int free;               /* free space left available */
 934         int delta;              /* additional delta to write normally */
 935         int more;               /* additional write granted */
 936         struct lrd lrd;
 937         int lsn;
 938         struct logsyncblk *lp;
 939         unsigned long flags;
 940
 941         /* push dirty metapages out to disk */
 942         if (hard_sync)
 943                 write_special_inodes(log, filemap_fdatawrite);
 944         else
 945                 write_special_inodes(log, filemap_flush);
 946
 947         /*
 948          *      forward syncpt
 949          */
 950         /* if last sync is same as last syncpt,
 951          * invoke sync point forward processing to update sync.
 952          */
 953
 954         if (log->sync == log->syncpt) {
 955                 LOGSYNC_LOCK(log, flags);
 956                 if (list_empty(&log->synclist))
 957                         log->sync = log->lsn;
 958                 else {
 959                         lp = list_entry(log->synclist.next,
 960                                         struct logsyncblk, synclist);
 961                         log->sync = lp->lsn;
 962                 }
 963                 LOGSYNC_UNLOCK(log, flags);
 964
 965         }
 966
 967         /* if sync is different from last syncpt,
 968          * write a SYNCPT record with syncpt = sync.
 969          * reset syncpt = sync
 970          */
 971         if (log->sync != log->syncpt) {
 972                 lrd.logtid = 0;
 973                 lrd.backchain = 0;
 974                 lrd.type = cpu_to_le16(LOG_SYNCPT);
 975                 lrd.length = 0;
 976                 lrd.log.syncpt.sync = cpu_to_le32(log->sync);
 977                 lsn = lmWriteRecord(log, NULL, &lrd, NULL);
 978
 979                 log->syncpt = log->sync;
 980         } else
 981                 lsn = log->lsn;
 982
 983         /*
 984          *      setup next syncpt trigger (SWAG)
 985          */
 986         logsize = log->logsize;
 987
 988         logdiff(written, lsn, log);
 989         free = logsize - written;
 990         delta = LOGSYNC_DELTA(logsize);
 991         more = min(free / 2, delta);
 992         if (more < 2 * LOGPSIZE) {
 993                 jfs_warn("\n ... Log Wrap ... Log Wrap ... Log Wrap ...\n");
 994                 /*
 995                  *      log wrapping
 996                  *
 997                  * option 1 - panic ? No.!
 998                  * option 2 - shutdown file systems
 999                  *            associated with log ?
1000                  * option 3 - extend log ?
1001                  * option 4 - second chance
1002                  *
1003                  * mark log wrapped, and continue.
1004                  * when all active transactions are completed,
1005                  * mark log valid for recovery.
1006                  * if crashed during invalid state, log state
1007                  * implies invalid log, forcing fsck().
1008                  */
1009                 /* mark log state log wrap in log superblock */
1010                 /* log->state = LOGWRAP; */
1011
1012                 /* reset sync point computation */
1013                 log->syncpt = log->sync = lsn;
1014                 log->nextsync = delta;
1015         } else
1016                 /* next syncpt trigger = written + more */
1017                 log->nextsync = written + more;
1018
1019         /* if number of bytes written from last sync point is more
1020          * than 1/4 of the log size, stop new transactions from
1021          * starting until all current transactions are completed
1022          * by setting syncbarrier flag.
1023          */
1024         if (!test_bit(log_SYNCBARRIER, &log->flag) &&
1025             (written > LOGSYNC_BARRIER(logsize)) && log->active) {
1026                 set_bit(log_SYNCBARRIER, &log->flag);
1027                 jfs_info("log barrier on: lsn=0x%x syncpt=0x%x", lsn,
1028                          log->syncpt);
1029                 /*
1030                  * We may have to initiate group commit
1031                  */
1032                 jfs_flush_journal(log, 0);
1033         }
1034
1035         return lsn;
1036 }
1037
1038 /*
1039  * NAME:        jfs_syncpt
1040  *
1041  * FUNCTION:    write log SYNCPT record for specified log
1042  *
1043  * PARAMETERS:  log       - log structure
1044  *              hard_sync - set to 1 to force metadata to be written
1045  */
1046 void jfs_syncpt(struct jfs_log *log, int hard_sync)
1047 {       LOG_LOCK(log);
1048         if (!test_bit(log_QUIESCE, &log->flag))
1049                 lmLogSync(log, hard_sync);
1050         LOG_UNLOCK(log);
1051 }
1052
1053 /*
1054  * NAME:        lmLogOpen()
1055  *
1056  * FUNCTION:    open the log on first open;
1057  *      insert filesystem in the active list of the log.
1058  *
1059  * PARAMETER:   ipmnt   - file system mount inode
1060  *              iplog   - log inode (out)
1061  *
1062  * RETURN:
1063  *
1064  * serialization:
1065  */
1066 int lmLogOpen(struct super_block *sb)
1067 {
1068         int rc;
1069         struct block_device *bdev;
1070         struct jfs_log *log;
1071         struct jfs_sb_info *sbi = JFS_SBI(sb);
1072
1073         if (sbi->flag & JFS_NOINTEGRITY)
1074                 return open_dummy_log(sb);
1075
1076         if (sbi->mntflag & JFS_INLINELOG)
1077                 return open_inline_log(sb);
1078
1079         mutex_lock(&jfs_log_mutex);
1080         list_for_each_entry(log, &jfs_external_logs, journal_list) {
1081                 if (log->bdev->bd_dev == sbi->logdev) {
1082                         if (!uuid_equal(&log->uuid, &sbi->loguuid)) {
1083                                 jfs_warn("wrong uuid on JFS journal");
1084                                 mutex_unlock(&jfs_log_mutex);
1085                                 return -EINVAL;
1086                         }
1087                         /*
1088                          * add file system to log active file system list
1089                          */
1090                         if ((rc = lmLogFileSystem(log, sbi, 1))) {
1091                                 mutex_unlock(&jfs_log_mutex);
1092                                 return rc;
1093                         }
1094                         goto journal_found;
1095                 }
1096         }
1097
1098         if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL))) {
1099                 mutex_unlock(&jfs_log_mutex);
1100                 return -ENOMEM;
1101         }
1102         INIT_LIST_HEAD(&log->sb_list);
1103         init_waitqueue_head(&log->syncwait);
1104
1105         /*
1106          *      external log as separate logical volume
1107          *
1108          * file systems to log may have n-to-1 relationship;
1109          */
1110
1111         bdev = blkdev_get_by_dev(sbi->logdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
1112                                  log);
1113         if (IS_ERR(bdev)) {
1114                 rc = PTR_ERR(bdev);
1115                 goto free;
1116         }
1117
1118         log->bdev = bdev;
1119         uuid_copy(&log->uuid, &sbi->loguuid);
1120
1121         /*
1122          * initialize log:
1123          */
1124         if ((rc = lmLogInit(log)))
1125                 goto close;
1126
1127         list_add(&log->journal_list, &jfs_external_logs);
1128
1129         /*
1130          * add file system to log active file system list
1131          */
1132         if ((rc = lmLogFileSystem(log, sbi, 1)))
1133                 goto shutdown;
1134
1135 journal_found:
1136         LOG_LOCK(log);
1137         list_add(&sbi->log_list, &log->sb_list);
1138         sbi->log = log;
1139         LOG_UNLOCK(log);
1140
1141         mutex_unlock(&jfs_log_mutex);
1142         return 0;
1143
1144         /*
1145          *      unwind on error
1146          */
1147       shutdown:         /* unwind lbmLogInit() */
1148         list_del(&log->journal_list);
1149         lbmLogShutdown(log);
1150
1151       close:            /* close external log device */
1152         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1153
1154       free:             /* free log descriptor */
1155         mutex_unlock(&jfs_log_mutex);
1156         kfree(log);
1157
1158         jfs_warn("lmLogOpen: exit(%d)", rc);
1159         return rc;
1160 }
1161
1162 static int open_inline_log(struct super_block *sb)
1163 {
1164         struct jfs_log *log;
1165         int rc;
1166
1167         if (!(log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL)))
1168                 return -ENOMEM;
1169         INIT_LIST_HEAD(&log->sb_list);
1170         init_waitqueue_head(&log->syncwait);
1171
1172         set_bit(log_INLINELOG, &log->flag);
1173         log->bdev = sb->s_bdev;
1174         log->base = addressPXD(&JFS_SBI(sb)->logpxd);
1175         log->size = lengthPXD(&JFS_SBI(sb)->logpxd) >>
1176             (L2LOGPSIZE - sb->s_blocksize_bits);
1177         log->l2bsize = sb->s_blocksize_bits;
1178         ASSERT(L2LOGPSIZE >= sb->s_blocksize_bits);
1179
1180         /*
1181          * initialize log.
1182          */
1183         if ((rc = lmLogInit(log))) {
1184                 kfree(log);
1185                 jfs_warn("lmLogOpen: exit(%d)", rc);
1186                 return rc;
1187         }
1188
1189         list_add(&JFS_SBI(sb)->log_list, &log->sb_list);
1190         JFS_SBI(sb)->log = log;
1191
1192         return rc;
1193 }
1194
1195 static int open_dummy_log(struct super_block *sb)
1196 {
1197         int rc;
1198
1199         mutex_lock(&jfs_log_mutex);
1200         if (!dummy_log) {
1201                 dummy_log = kzalloc(sizeof(struct jfs_log), GFP_KERNEL);
1202                 if (!dummy_log) {
1203                         mutex_unlock(&jfs_log_mutex);
1204                         return -ENOMEM;
1205                 }
1206                 INIT_LIST_HEAD(&dummy_log->sb_list);
1207                 init_waitqueue_head(&dummy_log->syncwait);
1208                 dummy_log->no_integrity = 1;
1209                 /* Make up some stuff */
1210                 dummy_log->base = 0;
1211                 dummy_log->size = 1024;
1212                 rc = lmLogInit(dummy_log);
1213                 if (rc) {
1214                         kfree(dummy_log);
1215                         dummy_log = NULL;
1216                         mutex_unlock(&jfs_log_mutex);
1217                         return rc;
1218                 }
1219         }
1220
1221         LOG_LOCK(dummy_log);
1222         list_add(&JFS_SBI(sb)->log_list, &dummy_log->sb_list);
1223         JFS_SBI(sb)->log = dummy_log;
1224         LOG_UNLOCK(dummy_log);
1225         mutex_unlock(&jfs_log_mutex);
1226
1227         return 0;
1228 }
1229
1230 /*
1231  * NAME:        lmLogInit()
1232  *
1233  * FUNCTION:    log initialization at first log open.
1234  *
1235  *      logredo() (or logformat()) should have been run previously.
1236  *      initialize the log from log superblock.
1237  *      set the log state in the superblock to LOGMOUNT and
1238  *      write SYNCPT log record.
1239  *
1240  * PARAMETER:   log     - log structure
1241  *
1242  * RETURN:      0       - if ok
1243  *              -EINVAL - bad log magic number or superblock dirty
1244  *              error returned from logwait()
1245  *
1246  * serialization: single first open thread
1247  */
1248 int lmLogInit(struct jfs_log * log)
1249 {
1250         int rc = 0;
1251         struct lrd lrd;
1252         struct logsuper *logsuper;
1253         struct lbuf *bpsuper;
1254         struct lbuf *bp;
1255         struct logpage *lp;
1256         int lsn = 0;
1257
1258         jfs_info("lmLogInit: log:0x%p", log);
1259
1260         /* initialize the group commit serialization lock */
1261         LOGGC_LOCK_INIT(log);
1262
1263         /* allocate/initialize the log write serialization lock */
1264         LOG_LOCK_INIT(log);
1265
1266         LOGSYNC_LOCK_INIT(log);
1267
1268         INIT_LIST_HEAD(&log->synclist);
1269
1270         INIT_LIST_HEAD(&log->cqueue);
1271         log->flush_tblk = NULL;
1272
1273         log->count = 0;
1274
1275         /*
1276          * initialize log i/o
1277          */
1278         if ((rc = lbmLogInit(log)))
1279                 return rc;
1280
1281         if (!test_bit(log_INLINELOG, &log->flag))
1282                 log->l2bsize = L2LOGPSIZE;
1283
1284         /* check for disabled journaling to disk */
1285         if (log->no_integrity) {
1286                 /*
1287                  * Journal pages will still be filled.  When the time comes
1288                  * to actually do the I/O, the write is not done, and the
1289                  * endio routine is called directly.
1290                  */
1291                 bp = lbmAllocate(log , 0);
1292                 log->bp = bp;
1293                 bp->l_pn = bp->l_eor = 0;
1294         } else {
1295                 /*
1296                  * validate log superblock
1297                  */
1298                 if ((rc = lbmRead(log, 1, &bpsuper)))
1299                         goto errout10;
1300
1301                 logsuper = (struct logsuper *) bpsuper->l_ldata;
1302
1303                 if (logsuper->magic != cpu_to_le32(LOGMAGIC)) {
1304                         jfs_warn("*** Log Format Error ! ***");
1305                         rc = -EINVAL;
1306                         goto errout20;
1307                 }
1308
1309                 /* logredo() should have been run successfully. */
1310                 if (logsuper->state != cpu_to_le32(LOGREDONE)) {
1311                         jfs_warn("*** Log Is Dirty ! ***");
1312                         rc = -EINVAL;
1313                         goto errout20;
1314                 }
1315
1316                 /* initialize log from log superblock */
1317                 if (test_bit(log_INLINELOG,&log->flag)) {
1318                         if (log->size != le32_to_cpu(logsuper->size)) {
1319                                 rc = -EINVAL;
1320                                 goto errout20;
1321                         }
1322                         jfs_info("lmLogInit: inline log:0x%p base:0x%Lx size:0x%x",
1323                                  log, (unsigned long long)log->base, log->size);
1324                 } else {
1325                         if (!uuid_equal(&logsuper->uuid, &log->uuid)) {
1326                                 jfs_warn("wrong uuid on JFS log device");
1327                                 goto errout20;
1328                         }
1329                         log->size = le32_to_cpu(logsuper->size);
1330                         log->l2bsize = le32_to_cpu(logsuper->l2bsize);
1331                         jfs_info("lmLogInit: external log:0x%p base:0x%Lx size:0x%x",
1332                                  log, (unsigned long long)log->base, log->size);
1333                 }
1334
1335                 log->page = le32_to_cpu(logsuper->end) / LOGPSIZE;
1336                 log->eor = le32_to_cpu(logsuper->end) - (LOGPSIZE * log->page);
1337
1338                 /*
1339                  * initialize for log append write mode
1340                  */
1341                 /* establish current/end-of-log page/buffer */
1342                 if ((rc = lbmRead(log, log->page, &bp)))
1343                         goto errout20;
1344
1345                 lp = (struct logpage *) bp->l_ldata;
1346
1347                 jfs_info("lmLogInit: lsn:0x%x page:%d eor:%d:%d",
1348                          le32_to_cpu(logsuper->end), log->page, log->eor,
1349                          le16_to_cpu(lp->h.eor));
1350
1351                 log->bp = bp;
1352                 bp->l_pn = log->page;
1353                 bp->l_eor = log->eor;
1354
1355                 /* if current page is full, move on to next page */
1356                 if (log->eor >= LOGPSIZE - LOGPTLRSIZE)
1357                         lmNextPage(log);
1358
1359                 /*
1360                  * initialize log syncpoint
1361                  */
1362                 /*
1363                  * write the first SYNCPT record with syncpoint = 0
1364                  * (i.e., log redo up to HERE !);
1365                  * remove current page from lbm write queue at end of pageout
1366                  * (to write log superblock update), but do not release to
1367                  * freelist;
1368                  */
1369                 lrd.logtid = 0;
1370                 lrd.backchain = 0;
1371                 lrd.type = cpu_to_le16(LOG_SYNCPT);
1372                 lrd.length = 0;
1373                 lrd.log.syncpt.sync = 0;
1374                 lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1375                 bp = log->bp;
1376                 bp->l_ceor = bp->l_eor;
1377                 lp = (struct logpage *) bp->l_ldata;
1378                 lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1379                 lbmWrite(log, bp, lbmWRITE | lbmSYNC, 0);
1380                 if ((rc = lbmIOWait(bp, 0)))
1381                         goto errout30;
1382
1383                 /*
1384                  * update/write superblock
1385                  */
1386                 logsuper->state = cpu_to_le32(LOGMOUNT);
1387                 log->serial = le32_to_cpu(logsuper->serial) + 1;
1388                 logsuper->serial = cpu_to_le32(log->serial);
1389                 lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1390                 if ((rc = lbmIOWait(bpsuper, lbmFREE)))
1391                         goto errout30;
1392         }
1393
1394         /* initialize logsync parameters */
1395         log->logsize = (log->size - 2) << L2LOGPSIZE;
1396         log->lsn = lsn;
1397         log->syncpt = lsn;
1398         log->sync = log->syncpt;
1399         log->nextsync = LOGSYNC_DELTA(log->logsize);
1400
1401         jfs_info("lmLogInit: lsn:0x%x syncpt:0x%x sync:0x%x",
1402                  log->lsn, log->syncpt, log->sync);
1403
1404         /*
1405          * initialize for lazy/group commit
1406          */
1407         log->clsn = lsn;
1408
1409         return 0;
1410
1411         /*
1412          *      unwind on error
1413          */
1414       errout30:         /* release log page */
1415         log->wqueue = NULL;
1416         bp->l_wqnext = NULL;
1417         lbmFree(bp);
1418
1419       errout20:         /* release log superblock */
1420         lbmFree(bpsuper);
1421
1422       errout10:         /* unwind lbmLogInit() */
1423         lbmLogShutdown(log);
1424
1425         jfs_warn("lmLogInit: exit(%d)", rc);
1426         return rc;
1427 }
1428
1429
1430 /*
1431  * NAME:        lmLogClose()
1432  *
1433  * FUNCTION:    remove file system <ipmnt> from active list of log <iplog>
1434  *              and close it on last close.
1435  *
1436  * PARAMETER:   sb      - superblock
1437  *
1438  * RETURN:      errors from subroutines
1439  *
1440  * serialization:
1441  */
1442 int lmLogClose(struct super_block *sb)
1443 {
1444         struct jfs_sb_info *sbi = JFS_SBI(sb);
1445         struct jfs_log *log = sbi->log;
1446         struct block_device *bdev;
1447         int rc = 0;
1448
1449         jfs_info("lmLogClose: log:0x%p", log);
1450
1451         mutex_lock(&jfs_log_mutex);
1452         LOG_LOCK(log);
1453         list_del(&sbi->log_list);
1454         LOG_UNLOCK(log);
1455         sbi->log = NULL;
1456
1457         /*
1458          * We need to make sure all of the "written" metapages
1459          * actually make it to disk
1460          */
1461         sync_blockdev(sb->s_bdev);
1462
1463         if (test_bit(log_INLINELOG, &log->flag)) {
1464                 /*
1465                  *      in-line log in host file system
1466                  */
1467                 rc = lmLogShutdown(log);
1468                 kfree(log);
1469                 goto out;
1470         }
1471
1472         if (!log->no_integrity)
1473                 lmLogFileSystem(log, sbi, 0);
1474
1475         if (!list_empty(&log->sb_list))
1476                 goto out;
1477
1478         /*
1479          * TODO: ensure that the dummy_log is in a state to allow
1480          * lbmLogShutdown to deallocate all the buffers and call
1481          * kfree against dummy_log.  For now, leave dummy_log & its
1482          * buffers in memory, and resuse if another no-integrity mount
1483          * is requested.
1484          */
1485         if (log->no_integrity)
1486                 goto out;
1487
1488         /*
1489          *      external log as separate logical volume
1490          */
1491         list_del(&log->journal_list);
1492         bdev = log->bdev;
1493         rc = lmLogShutdown(log);
1494
1495         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1496
1497         kfree(log);
1498
1499       out:
1500         mutex_unlock(&jfs_log_mutex);
1501         jfs_info("lmLogClose: exit(%d)", rc);
1502         return rc;
1503 }
1504
1505
1506 /*
1507  * NAME:        jfs_flush_journal()
1508  *
1509  * FUNCTION:    initiate write of any outstanding transactions to the journal
1510  *              and optionally wait until they are all written to disk
1511  *
1512  *              wait == 0  flush until latest txn is committed, don't wait
1513  *              wait == 1  flush until latest txn is committed, wait
1514  *              wait > 1   flush until all txn's are complete, wait
1515  */
1516 void jfs_flush_journal(struct jfs_log *log, int wait)
1517 {
1518         int i;
1519         struct tblock *target = NULL;
1520
1521         /* jfs_write_inode may call us during read-only mount */
1522         if (!log)
1523                 return;
1524
1525         jfs_info("jfs_flush_journal: log:0x%p wait=%d", log, wait);
1526
1527         LOGGC_LOCK(log);
1528
1529         if (!list_empty(&log->cqueue)) {
1530                 /*
1531                  * This ensures that we will keep writing to the journal as long
1532                  * as there are unwritten commit records
1533                  */
1534                 target = list_entry(log->cqueue.prev, struct tblock, cqueue);
1535
1536                 if (test_bit(log_FLUSH, &log->flag)) {
1537                         /*
1538                          * We're already flushing.
1539                          * if flush_tblk is NULL, we are flushing everything,
1540                          * so leave it that way.  Otherwise, update it to the
1541                          * latest transaction
1542                          */
1543                         if (log->flush_tblk)
1544                                 log->flush_tblk = target;
1545                 } else {
1546                         /* Only flush until latest transaction is committed */
1547                         log->flush_tblk = target;
1548                         set_bit(log_FLUSH, &log->flag);
1549
1550                         /*
1551                          * Initiate I/O on outstanding transactions
1552                          */
1553                         if (!(log->cflag & logGC_PAGEOUT)) {
1554                                 log->cflag |= logGC_PAGEOUT;
1555                                 lmGCwrite(log, 0);
1556                         }
1557                 }
1558         }
1559         if ((wait > 1) || test_bit(log_SYNCBARRIER, &log->flag)) {
1560                 /* Flush until all activity complete */
1561                 set_bit(log_FLUSH, &log->flag);
1562                 log->flush_tblk = NULL;
1563         }
1564
1565         if (wait && target && !(target->flag & tblkGC_COMMITTED)) {
1566                 DECLARE_WAITQUEUE(__wait, current);
1567
1568                 add_wait_queue(&target->gcwait, &__wait);
1569                 set_current_state(TASK_UNINTERRUPTIBLE);
1570                 LOGGC_UNLOCK(log);
1571                 schedule();
1572                 LOGGC_LOCK(log);
1573                 remove_wait_queue(&target->gcwait, &__wait);
1574         }
1575         LOGGC_UNLOCK(log);
1576
1577         if (wait < 2)
1578                 return;
1579
1580         write_special_inodes(log, filemap_fdatawrite);
1581
1582         /*
1583          * If there was recent activity, we may need to wait
1584          * for the lazycommit thread to catch up
1585          */
1586         if ((!list_empty(&log->cqueue)) || !list_empty(&log->synclist)) {
1587                 for (i = 0; i < 200; i++) {     /* Too much? */
1588                         msleep(250);
1589                         write_special_inodes(log, filemap_fdatawrite);
1590                         if (list_empty(&log->cqueue) &&
1591                             list_empty(&log->synclist))
1592                                 break;
1593                 }
1594         }
1595         assert(list_empty(&log->cqueue));
1596
1597 #ifdef CONFIG_JFS_DEBUG
1598         if (!list_empty(&log->synclist)) {
1599                 struct logsyncblk *lp;
1600
1601                 printk(KERN_ERR "jfs_flush_journal: synclist not empty\n");
1602                 list_for_each_entry(lp, &log->synclist, synclist) {
1603                         if (lp->xflag & COMMIT_PAGE) {
1604                                 struct metapage *mp = (struct metapage *)lp;
1605                                 print_hex_dump(KERN_ERR, "metapage: ",
1606                                                DUMP_PREFIX_ADDRESS, 16, 4,
1607                                                mp, sizeof(struct metapage), 0);
1608                                 print_hex_dump(KERN_ERR, "page: ",
1609                                                DUMP_PREFIX_ADDRESS, 16,
1610                                                sizeof(long), mp->page,
1611                                                sizeof(struct page), 0);
1612                         } else
1613                                 print_hex_dump(KERN_ERR, "tblock:",
1614                                                DUMP_PREFIX_ADDRESS, 16, 4,
1615                                                lp, sizeof(struct tblock), 0);
1616                 }
1617         }
1618 #else
1619         WARN_ON(!list_empty(&log->synclist));
1620 #endif
1621         clear_bit(log_FLUSH, &log->flag);
1622 }
1623
1624 /*
1625  * NAME:        lmLogShutdown()
1626  *
1627  * FUNCTION:    log shutdown at last LogClose().
1628  *
1629  *              write log syncpt record.
1630  *              update super block to set redone flag to 0.
1631  *
1632  * PARAMETER:   log     - log inode
1633  *
1634  * RETURN:      0       - success
1635  *
1636  * serialization: single last close thread
1637  */
1638 int lmLogShutdown(struct jfs_log * log)
1639 {
1640         int rc;
1641         struct lrd lrd;
1642         int lsn;
1643         struct logsuper *logsuper;
1644         struct lbuf *bpsuper;
1645         struct lbuf *bp;
1646         struct logpage *lp;
1647
1648         jfs_info("lmLogShutdown: log:0x%p", log);
1649
1650         jfs_flush_journal(log, 2);
1651
1652         /*
1653          * write the last SYNCPT record with syncpoint = 0
1654          * (i.e., log redo up to HERE !)
1655          */
1656         lrd.logtid = 0;
1657         lrd.backchain = 0;
1658         lrd.type = cpu_to_le16(LOG_SYNCPT);
1659         lrd.length = 0;
1660         lrd.log.syncpt.sync = 0;
1661
1662         lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1663         bp = log->bp;
1664         lp = (struct logpage *) bp->l_ldata;
1665         lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1666         lbmWrite(log, log->bp, lbmWRITE | lbmRELEASE | lbmSYNC, 0);
1667         lbmIOWait(log->bp, lbmFREE);
1668         log->bp = NULL;
1669
1670         /*
1671          * synchronous update log superblock
1672          * mark log state as shutdown cleanly
1673          * (i.e., Log does not need to be replayed).
1674          */
1675         if ((rc = lbmRead(log, 1, &bpsuper)))
1676                 goto out;
1677
1678         logsuper = (struct logsuper *) bpsuper->l_ldata;
1679         logsuper->state = cpu_to_le32(LOGREDONE);
1680         logsuper->end = cpu_to_le32(lsn);
1681         lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1682         rc = lbmIOWait(bpsuper, lbmFREE);
1683
1684         jfs_info("lmLogShutdown: lsn:0x%x page:%d eor:%d",
1685                  lsn, log->page, log->eor);
1686
1687       out:
1688         /*
1689          * shutdown per log i/o
1690          */
1691         lbmLogShutdown(log);
1692
1693         if (rc) {
1694                 jfs_warn("lmLogShutdown: exit(%d)", rc);
1695         }
1696         return rc;
1697 }
1698
1699
1700 /*
1701  * NAME:        lmLogFileSystem()
1702  *
1703  * FUNCTION:    insert (<activate> = true)/remove (<activate> = false)
1704  *      file system into/from log active file system list.
1705  *
1706  * PARAMETE:    log     - pointer to logs inode.
1707  *              fsdev   - kdev_t of filesystem.
1708  *              serial  - pointer to returned log serial number
1709  *              activate - insert/remove device from active list.
1710  *
1711  * RETURN:      0       - success
1712  *              errors returned by vms_iowait().
1713  */
1714 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
1715                            int activate)
1716 {
1717         int rc = 0;
1718         int i;
1719         struct logsuper *logsuper;
1720         struct lbuf *bpsuper;
1721         uuid_t *uuid = &sbi->uuid;
1722
1723         /*
1724          * insert/remove file system device to log active file system list.
1725          */
1726         if ((rc = lbmRead(log, 1, &bpsuper)))
1727                 return rc;
1728
1729         logsuper = (struct logsuper *) bpsuper->l_ldata;
1730         if (activate) {
1731                 for (i = 0; i < MAX_ACTIVE; i++)
1732                         if (uuid_is_null(&logsuper->active[i].uuid)) {
1733                                 uuid_copy(&logsuper->active[i].uuid, uuid);
1734                                 sbi->aggregate = i;
1735                                 break;
1736                         }
1737                 if (i == MAX_ACTIVE) {
1738                         jfs_warn("Too many file systems sharing journal!");
1739                         lbmFree(bpsuper);
1740                         return -EMFILE; /* Is there a better rc? */
1741                 }
1742         } else {
1743                 for (i = 0; i < MAX_ACTIVE; i++)
1744                         if (uuid_equal(&logsuper->active[i].uuid, uuid)) {
1745                                 uuid_copy(&logsuper->active[i].uuid,
1746                                           &uuid_null);
1747                                 break;
1748                         }
1749                 if (i == MAX_ACTIVE) {
1750                         jfs_warn("Somebody stomped on the journal!");
1751                         lbmFree(bpsuper);
1752                         return -EIO;
1753                 }
1754
1755         }
1756
1757         /*
1758          * synchronous write log superblock:
1759          *
1760          * write sidestream bypassing write queue:
1761          * at file system mount, log super block is updated for
1762          * activation of the file system before any log record
1763          * (MOUNT record) of the file system, and at file system
1764          * unmount, all meta data for the file system has been
1765          * flushed before log super block is updated for deactivation
1766          * of the file system.
1767          */
1768         lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1769         rc = lbmIOWait(bpsuper, lbmFREE);
1770
1771         return rc;
1772 }
1773
1774 /*
1775  *              log buffer manager (lbm)
1776  *              ------------------------
1777  *
1778  * special purpose buffer manager supporting log i/o requirements.
1779  *
1780  * per log write queue:
1781  * log pageout occurs in serial order by fifo write queue and
1782  * restricting to a single i/o in pregress at any one time.
1783  * a circular singly-linked list
1784  * (log->wrqueue points to the tail, and buffers are linked via
1785  * bp->wrqueue field), and
1786  * maintains log page in pageout ot waiting for pageout in serial pageout.
1787  */
1788
1789 /*
1790  *      lbmLogInit()
1791  *
1792  * initialize per log I/O setup at lmLogInit()
1793  */
1794 static int lbmLogInit(struct jfs_log * log)
1795 {                               /* log inode */
1796         int i;
1797         struct lbuf *lbuf;
1798
1799         jfs_info("lbmLogInit: log:0x%p", log);
1800
1801         /* initialize current buffer cursor */
1802         log->bp = NULL;
1803
1804         /* initialize log device write queue */
1805         log->wqueue = NULL;
1806
1807         /*
1808          * Each log has its own buffer pages allocated to it.  These are
1809          * not managed by the page cache.  This ensures that a transaction
1810          * writing to the log does not block trying to allocate a page from
1811          * the page cache (for the log).  This would be bad, since page
1812          * allocation waits on the kswapd thread that may be committing inodes
1813          * which would cause log activity.  Was that clear?  I'm trying to
1814          * avoid deadlock here.
1815          */
1816         init_waitqueue_head(&log->free_wait);
1817
1818         log->lbuf_free = NULL;
1819
1820         for (i = 0; i < LOGPAGES;) {
1821                 char *buffer;
1822                 uint offset;
1823                 struct page *page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1824
1825                 if (!page)
1826                         goto error;
1827                 buffer = page_address(page);
1828                 for (offset = 0; offset < PAGE_SIZE; offset += LOGPSIZE) {
1829                         lbuf = kmalloc(sizeof(struct lbuf), GFP_KERNEL);
1830                         if (lbuf == NULL) {
1831                                 if (offset == 0)
1832                                         __free_page(page);
1833                                 goto error;
1834                         }
1835                         if (offset) /* we already have one reference */
1836                                 get_page(page);
1837                         lbuf->l_offset = offset;
1838                         lbuf->l_ldata = buffer + offset;
1839                         lbuf->l_page = page;
1840                         lbuf->l_log = log;
1841                         init_waitqueue_head(&lbuf->l_ioevent);
1842
1843                         lbuf->l_freelist = log->lbuf_free;
1844                         log->lbuf_free = lbuf;
1845                         i++;
1846                 }
1847         }
1848
1849         return (0);
1850
1851       error:
1852         lbmLogShutdown(log);
1853         return -ENOMEM;
1854 }
1855
1856
1857 /*
1858  *      lbmLogShutdown()
1859  *
1860  * finalize per log I/O setup at lmLogShutdown()
1861  */
1862 static void lbmLogShutdown(struct jfs_log * log)
1863 {
1864         struct lbuf *lbuf;
1865
1866         jfs_info("lbmLogShutdown: log:0x%p", log);
1867
1868         lbuf = log->lbuf_free;
1869         while (lbuf) {
1870                 struct lbuf *next = lbuf->l_freelist;
1871                 __free_page(lbuf->l_page);
1872                 kfree(lbuf);
1873                 lbuf = next;
1874         }
1875 }
1876
1877
1878 /*
1879  *      lbmAllocate()
1880  *
1881  * allocate an empty log buffer
1882  */
1883 static struct lbuf *lbmAllocate(struct jfs_log * log, int pn)
1884 {
1885         struct lbuf *bp;
1886         unsigned long flags;
1887
1888         /*
1889          * recycle from log buffer freelist if any
1890          */
1891         LCACHE_LOCK(flags);
1892         LCACHE_SLEEP_COND(log->free_wait, (bp = log->lbuf_free), flags);
1893         log->lbuf_free = bp->l_freelist;
1894         LCACHE_UNLOCK(flags);
1895
1896         bp->l_flag = 0;
1897
1898         bp->l_wqnext = NULL;
1899         bp->l_freelist = NULL;
1900
1901         bp->l_pn = pn;
1902         bp->l_blkno = log->base + (pn << (L2LOGPSIZE - log->l2bsize));
1903         bp->l_ceor = 0;
1904
1905         return bp;
1906 }
1907
1908
1909 /*
1910  *      lbmFree()
1911  *
1912  * release a log buffer to freelist
1913  */
1914 static void lbmFree(struct lbuf * bp)
1915 {
1916         unsigned long flags;
1917
1918         LCACHE_LOCK(flags);
1919
1920         lbmfree(bp);
1921
1922         LCACHE_UNLOCK(flags);
1923 }
1924
1925 static void lbmfree(struct lbuf * bp)
1926 {
1927         struct jfs_log *log = bp->l_log;
1928
1929         assert(bp->l_wqnext == NULL);
1930
1931         /*
1932          * return the buffer to head of freelist
1933          */
1934         bp->l_freelist = log->lbuf_free;
1935         log->lbuf_free = bp;
1936
1937         wake_up(&log->free_wait);
1938         return;
1939 }
1940
1941
1942 /*
1943  * NAME:        lbmRedrive
1944  *
1945  * FUNCTION:    add a log buffer to the log redrive list
1946  *
1947  * PARAMETER:
1948  *      bp      - log buffer
1949  *
1950  * NOTES:
1951  *      Takes log_redrive_lock.
1952  */
1953 static inline void lbmRedrive(struct lbuf *bp)
1954 {
1955         unsigned long flags;
1956
1957         spin_lock_irqsave(&log_redrive_lock, flags);
1958         bp->l_redrive_next = log_redrive_list;
1959         log_redrive_list = bp;
1960         spin_unlock_irqrestore(&log_redrive_lock, flags);
1961
1962         wake_up_process(jfsIOthread);
1963 }
1964
1965
1966 /*
1967  *      lbmRead()
1968  */
1969 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
1970 {
1971         struct bio *bio;
1972         struct lbuf *bp;
1973
1974         /*
1975          * allocate a log buffer
1976          */
1977         *bpp = bp = lbmAllocate(log, pn);
1978         jfs_info("lbmRead: bp:0x%p pn:0x%x", bp, pn);
1979
1980         bp->l_flag |= lbmREAD;
1981
1982         bio = bio_alloc(GFP_NOFS, 1);
1983
1984         bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
1985         bio_set_dev(bio, log->bdev);
1986
1987         bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
1988         BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
1989
1990         bio->bi_end_io = lbmIODone;
1991         bio->bi_private = bp;
1992         bio->bi_opf = REQ_OP_READ;
1993         /*check if journaling to disk has been disabled*/
1994         if (log->no_integrity) {
1995                 bio->bi_iter.bi_size = 0;
1996                 lbmIODone(bio);
1997         } else {
1998                 submit_bio(bio);
1999         }
2000
2001         wait_event(bp->l_ioevent, (bp->l_flag != lbmREAD));
2002
2003         return 0;
2004 }
2005
2006
2007 /*
2008  *      lbmWrite()
2009  *
2010  * buffer at head of pageout queue stays after completion of
2011  * partial-page pageout and redriven by explicit initiation of
2012  * pageout by caller until full-page pageout is completed and
2013  * released.
2014  *
2015  * device driver i/o done redrives pageout of new buffer at
2016  * head of pageout queue when current buffer at head of pageout
2017  * queue is released at the completion of its full-page pageout.
2018  *
2019  * LOGGC_LOCK() serializes lbmWrite() by lmNextPage() and lmGroupCommit().
2020  * LCACHE_LOCK() serializes xflag between lbmWrite() and lbmIODone()
2021  */
2022 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag,
2023                      int cant_block)
2024 {
2025         struct lbuf *tail;
2026         unsigned long flags;
2027
2028         jfs_info("lbmWrite: bp:0x%p flag:0x%x pn:0x%x", bp, flag, bp->l_pn);
2029
2030         /* map the logical block address to physical block address */
2031         bp->l_blkno =
2032             log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2033
2034         LCACHE_LOCK(flags);             /* disable+lock */
2035
2036         /*
2037          * initialize buffer for device driver
2038          */
2039         bp->l_flag = flag;
2040
2041         /*
2042          *      insert bp at tail of write queue associated with log
2043          *
2044          * (request is either for bp already/currently at head of queue
2045          * or new bp to be inserted at tail)
2046          */
2047         tail = log->wqueue;
2048
2049         /* is buffer not already on write queue ? */
2050         if (bp->l_wqnext == NULL) {
2051                 /* insert at tail of wqueue */
2052                 if (tail == NULL) {
2053                         log->wqueue = bp;
2054                         bp->l_wqnext = bp;
2055                 } else {
2056                         log->wqueue = bp;
2057                         bp->l_wqnext = tail->l_wqnext;
2058                         tail->l_wqnext = bp;
2059                 }
2060
2061                 tail = bp;
2062         }
2063
2064         /* is buffer at head of wqueue and for write ? */
2065         if ((bp != tail->l_wqnext) || !(flag & lbmWRITE)) {
2066                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2067                 return;
2068         }
2069
2070         LCACHE_UNLOCK(flags);   /* unlock+enable */
2071
2072         if (cant_block)
2073                 lbmRedrive(bp);
2074         else if (flag & lbmSYNC)
2075                 lbmStartIO(bp);
2076         else {
2077                 LOGGC_UNLOCK(log);
2078                 lbmStartIO(bp);
2079                 LOGGC_LOCK(log);
2080         }
2081 }
2082
2083
2084 /*
2085  *      lbmDirectWrite()
2086  *
2087  * initiate pageout bypassing write queue for sidestream
2088  * (e.g., log superblock) write;
2089  */
2090 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag)
2091 {
2092         jfs_info("lbmDirectWrite: bp:0x%p flag:0x%x pn:0x%x",
2093                  bp, flag, bp->l_pn);
2094
2095         /*
2096          * initialize buffer for device driver
2097          */
2098         bp->l_flag = flag | lbmDIRECT;
2099
2100         /* map the logical block address to physical block address */
2101         bp->l_blkno =
2102             log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2103
2104         /*
2105          *      initiate pageout of the page
2106          */
2107         lbmStartIO(bp);
2108 }
2109
2110
2111 /*
2112  * NAME:        lbmStartIO()
2113  *
2114  * FUNCTION:    Interface to DD strategy routine
2115  *
2116  * RETURN:      none
2117  *
2118  * serialization: LCACHE_LOCK() is NOT held during log i/o;
2119  */
2120 static void lbmStartIO(struct lbuf * bp)
2121 {
2122         struct bio *bio;
2123         struct jfs_log *log = bp->l_log;
2124
2125         jfs_info("lbmStartIO");
2126
2127         bio = bio_alloc(GFP_NOFS, 1);
2128         bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
2129         bio_set_dev(bio, log->bdev);
2130
2131         bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
2132         BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
2133
2134         bio->bi_end_io = lbmIODone;
2135         bio->bi_private = bp;
2136         bio->bi_opf = REQ_OP_WRITE | REQ_SYNC;
2137
2138         /* check if journaling to disk has been disabled */
2139         if (log->no_integrity) {
2140                 bio->bi_iter.bi_size = 0;
2141                 lbmIODone(bio);
2142         } else {
2143                 submit_bio(bio);
2144                 INCREMENT(lmStat.submitted);
2145         }
2146 }
2147
2148
2149 /*
2150  *      lbmIOWait()
2151  */
2152 static int lbmIOWait(struct lbuf * bp, int flag)
2153 {
2154         unsigned long flags;
2155         int rc = 0;
2156
2157         jfs_info("lbmIOWait1: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2158
2159         LCACHE_LOCK(flags);             /* disable+lock */
2160
2161         LCACHE_SLEEP_COND(bp->l_ioevent, (bp->l_flag & lbmDONE), flags);
2162
2163         rc = (bp->l_flag & lbmERROR) ? -EIO : 0;
2164
2165         if (flag & lbmFREE)
2166                 lbmfree(bp);
2167
2168         LCACHE_UNLOCK(flags);   /* unlock+enable */
2169
2170         jfs_info("lbmIOWait2: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2171         return rc;
2172 }
2173
2174 /*
2175  *      lbmIODone()
2176  *
2177  * executed at INTIODONE level
2178  */
2179 static void lbmIODone(struct bio *bio)
2180 {
2181         struct lbuf *bp = bio->bi_private;
2182         struct lbuf *nextbp, *tail;
2183         struct jfs_log *log;
2184         unsigned long flags;
2185
2186         /*
2187          * get back jfs buffer bound to the i/o buffer
2188          */
2189         jfs_info("lbmIODone: bp:0x%p flag:0x%x", bp, bp->l_flag);
2190
2191         LCACHE_LOCK(flags);             /* disable+lock */
2192
2193         bp->l_flag |= lbmDONE;
2194
2195         if (bio->bi_status) {
2196                 bp->l_flag |= lbmERROR;
2197
2198                 jfs_err("lbmIODone: I/O error in JFS log");
2199         }
2200
2201         bio_put(bio);
2202
2203         /*
2204          *      pagein completion
2205          */
2206         if (bp->l_flag & lbmREAD) {
2207                 bp->l_flag &= ~lbmREAD;
2208
2209                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2210
2211                 /* wakeup I/O initiator */
2212                 LCACHE_WAKEUP(&bp->l_ioevent);
2213
2214                 return;
2215         }
2216
2217         /*
2218          *      pageout completion
2219          *
2220          * the bp at the head of write queue has completed pageout.
2221          *
2222          * if single-commit/full-page pageout, remove the current buffer
2223          * from head of pageout queue, and redrive pageout with
2224          * the new buffer at head of pageout queue;
2225          * otherwise, the partial-page pageout buffer stays at
2226          * the head of pageout queue to be redriven for pageout
2227          * by lmGroupCommit() until full-page pageout is completed.
2228          */
2229         bp->l_flag &= ~lbmWRITE;
2230         INCREMENT(lmStat.pagedone);
2231
2232         /* update committed lsn */
2233         log = bp->l_log;
2234         log->clsn = (bp->l_pn << L2LOGPSIZE) + bp->l_ceor;
2235
2236         if (bp->l_flag & lbmDIRECT) {
2237                 LCACHE_WAKEUP(&bp->l_ioevent);
2238                 LCACHE_UNLOCK(flags);
2239                 return;
2240         }
2241
2242         tail = log->wqueue;
2243
2244         /* single element queue */
2245         if (bp == tail) {
2246                 /* remove head buffer of full-page pageout
2247                  * from log device write queue
2248                  */
2249                 if (bp->l_flag & lbmRELEASE) {
2250                         log->wqueue = NULL;
2251                         bp->l_wqnext = NULL;
2252                 }
2253         }
2254         /* multi element queue */
2255         else {
2256                 /* remove head buffer of full-page pageout
2257                  * from log device write queue
2258                  */
2259                 if (bp->l_flag & lbmRELEASE) {
2260                         nextbp = tail->l_wqnext = bp->l_wqnext;
2261                         bp->l_wqnext = NULL;
2262
2263                         /*
2264                          * redrive pageout of next page at head of write queue:
2265                          * redrive next page without any bound tblk
2266                          * (i.e., page w/o any COMMIT records), or
2267                          * first page of new group commit which has been
2268                          * queued after current page (subsequent pageout
2269                          * is performed synchronously, except page without
2270                          * any COMMITs) by lmGroupCommit() as indicated
2271                          * by lbmWRITE flag;
2272                          */
2273                         if (nextbp->l_flag & lbmWRITE) {
2274                                 /*
2275                                  * We can't do the I/O at interrupt time.
2276                                  * The jfsIO thread can do it
2277                                  */
2278                                 lbmRedrive(nextbp);
2279                         }
2280                 }
2281         }
2282
2283         /*
2284          *      synchronous pageout:
2285          *
2286          * buffer has not necessarily been removed from write queue
2287          * (e.g., synchronous write of partial-page with COMMIT):
2288          * leave buffer for i/o initiator to dispose
2289          */
2290         if (bp->l_flag & lbmSYNC) {
2291                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2292
2293                 /* wakeup I/O initiator */
2294                 LCACHE_WAKEUP(&bp->l_ioevent);
2295         }
2296
2297         /*
2298          *      Group Commit pageout:
2299          */
2300         else if (bp->l_flag & lbmGC) {
2301                 LCACHE_UNLOCK(flags);
2302                 lmPostGC(bp);
2303         }
2304
2305         /*
2306          *      asynchronous pageout:
2307          *
2308          * buffer must have been removed from write queue:
2309          * insert buffer at head of freelist where it can be recycled
2310          */
2311         else {
2312                 assert(bp->l_flag & lbmRELEASE);
2313                 assert(bp->l_flag & lbmFREE);
2314                 lbmfree(bp);
2315
2316                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2317         }
2318 }
2319
2320 int jfsIOWait(void *arg)
2321 {
2322         struct lbuf *bp;
2323
2324         do {
2325                 spin_lock_irq(&log_redrive_lock);
2326                 while ((bp = log_redrive_list)) {
2327                         log_redrive_list = bp->l_redrive_next;
2328                         bp->l_redrive_next = NULL;
2329                         spin_unlock_irq(&log_redrive_lock);
2330                         lbmStartIO(bp);
2331                         spin_lock_irq(&log_redrive_lock);
2332                 }
2333
2334                 if (freezing(current)) {
2335                         spin_unlock_irq(&log_redrive_lock);
2336                         try_to_freeze();
2337                 } else {
2338                         set_current_state(TASK_INTERRUPTIBLE);
2339                         spin_unlock_irq(&log_redrive_lock);
2340                         schedule();
2341                 }
2342         } while (!kthread_should_stop());
2343
2344         jfs_info("jfsIOWait being killed!");
2345         return 0;
2346 }
2347
2348 /*
2349  * NAME:        lmLogFormat()/jfs_logform()
2350  *
2351  * FUNCTION:    format file system log
2352  *
2353  * PARAMETERS:
2354  *      log     - volume log
2355  *      logAddress - start address of log space in FS block
2356  *      logSize - length of log space in FS block;
2357  *
2358  * RETURN:      0       - success
2359  *              -EIO    - i/o error
2360  *
2361  * XXX: We're synchronously writing one page at a time.  This needs to
2362  *      be improved by writing multiple pages at once.
2363  */
2364 int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize)
2365 {
2366         int rc = -EIO;
2367         struct jfs_sb_info *sbi;
2368         struct logsuper *logsuper;
2369         struct logpage *lp;
2370         int lspn;               /* log sequence page number */
2371         struct lrd *lrd_ptr;
2372         int npages = 0;
2373         struct lbuf *bp;
2374
2375         jfs_info("lmLogFormat: logAddress:%Ld logSize:%d",
2376                  (long long)logAddress, logSize);
2377
2378         sbi = list_entry(log->sb_list.next, struct jfs_sb_info, log_list);
2379
2380         /* allocate a log buffer */
2381         bp = lbmAllocate(log, 1);
2382
2383         npages = logSize >> sbi->l2nbperpage;
2384
2385         /*
2386          *      log space:
2387          *
2388          * page 0 - reserved;
2389          * page 1 - log superblock;
2390          * page 2 - log data page: A SYNC log record is written
2391          *          into this page at logform time;
2392          * pages 3-N - log data page: set to empty log data pages;
2393          */
2394         /*
2395          *      init log superblock: log page 1
2396          */
2397         logsuper = (struct logsuper *) bp->l_ldata;
2398
2399         logsuper->magic = cpu_to_le32(LOGMAGIC);
2400         logsuper->version = cpu_to_le32(LOGVERSION);
2401         logsuper->state = cpu_to_le32(LOGREDONE);
2402         logsuper->flag = cpu_to_le32(sbi->mntflag);     /* ? */
2403         logsuper->size = cpu_to_le32(npages);
2404         logsuper->bsize = cpu_to_le32(sbi->bsize);
2405         logsuper->l2bsize = cpu_to_le32(sbi->l2bsize);
2406         logsuper->end = cpu_to_le32(2 * LOGPSIZE + LOGPHDRSIZE + LOGRDSIZE);
2407
2408         bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2409         bp->l_blkno = logAddress + sbi->nbperpage;
2410         lbmStartIO(bp);
2411         if ((rc = lbmIOWait(bp, 0)))
2412                 goto exit;
2413
2414         /*
2415          *      init pages 2 to npages-1 as log data pages:
2416          *
2417          * log page sequence number (lpsn) initialization:
2418          *
2419          * pn:   0     1     2     3                 n-1
2420          *       +-----+-----+=====+=====+===.....===+=====+
2421          * lspn:             N-1   0     1           N-2
2422          *                   <--- N page circular file ---->
2423          *
2424          * the N (= npages-2) data pages of the log is maintained as
2425          * a circular file for the log records;
2426          * lpsn grows by 1 monotonically as each log page is written
2427          * to the circular file of the log;
2428          * and setLogpage() will not reset the page number even if
2429          * the eor is equal to LOGPHDRSIZE. In order for binary search
2430          * still work in find log end process, we have to simulate the
2431          * log wrap situation at the log format time.
2432          * The 1st log page written will have the highest lpsn. Then
2433          * the succeeding log pages will have ascending order of
2434          * the lspn starting from 0, ... (N-2)
2435          */
2436         lp = (struct logpage *) bp->l_ldata;
2437         /*
2438          * initialize 1st log page to be written: lpsn = N - 1,
2439          * write a SYNCPT log record is written to this page
2440          */
2441         lp->h.page = lp->t.page = cpu_to_le32(npages - 3);
2442         lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE + LOGRDSIZE);
2443
2444         lrd_ptr = (struct lrd *) &lp->data;
2445         lrd_ptr->logtid = 0;
2446         lrd_ptr->backchain = 0;
2447         lrd_ptr->type = cpu_to_le16(LOG_SYNCPT);
2448         lrd_ptr->length = 0;
2449         lrd_ptr->log.syncpt.sync = 0;
2450
2451         bp->l_blkno += sbi->nbperpage;
2452         bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2453         lbmStartIO(bp);
2454         if ((rc = lbmIOWait(bp, 0)))
2455                 goto exit;
2456
2457         /*
2458          *      initialize succeeding log pages: lpsn = 0, 1, ..., (N-2)
2459          */
2460         for (lspn = 0; lspn < npages - 3; lspn++) {
2461                 lp->h.page = lp->t.page = cpu_to_le32(lspn);
2462                 lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
2463
2464                 bp->l_blkno += sbi->nbperpage;
2465                 bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2466                 lbmStartIO(bp);
2467                 if ((rc = lbmIOWait(bp, 0)))
2468                         goto exit;
2469         }
2470
2471         rc = 0;
2472 exit:
2473         /*
2474          *      finalize log
2475          */
2476         /* release the buffer */
2477         lbmFree(bp);
2478
2479         return rc;
2480 }
2481
2482 #ifdef CONFIG_JFS_STATISTICS
2483 int jfs_lmstats_proc_show(struct seq_file *m, void *v)
2484 {
2485         seq_printf(m,
2486                        "JFS Logmgr stats\n"
2487                        "================\n"
2488                        "commits = %d\n"
2489                        "writes submitted = %d\n"
2490                        "writes completed = %d\n"
2491                        "full pages submitted = %d\n"
2492                        "partial pages submitted = %d\n",
2493                        lmStat.commit,
2494                        lmStat.submitted,
2495                        lmStat.pagedone,
2496                        lmStat.full_page,
2497                        lmStat.partial_page);
2498         return 0;
2499 }
2500 #endif /* CONFIG_JFS_STATISTICS */