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                                 rc = -EINVAL;
1328                                 goto errout20;
1329                         }
1330                         log->size = le32_to_cpu(logsuper->size);
1331                         log->l2bsize = le32_to_cpu(logsuper->l2bsize);
1332                         jfs_info("lmLogInit: external log:0x%p base:0x%Lx size:0x%x",
1333                                  log, (unsigned long long)log->base, log->size);
1334                 }
1335
1336                 log->page = le32_to_cpu(logsuper->end) / LOGPSIZE;
1337                 log->eor = le32_to_cpu(logsuper->end) - (LOGPSIZE * log->page);
1338
1339                 /*
1340                  * initialize for log append write mode
1341                  */
1342                 /* establish current/end-of-log page/buffer */
1343                 if ((rc = lbmRead(log, log->page, &bp)))
1344                         goto errout20;
1345
1346                 lp = (struct logpage *) bp->l_ldata;
1347
1348                 jfs_info("lmLogInit: lsn:0x%x page:%d eor:%d:%d",
1349                          le32_to_cpu(logsuper->end), log->page, log->eor,
1350                          le16_to_cpu(lp->h.eor));
1351
1352                 log->bp = bp;
1353                 bp->l_pn = log->page;
1354                 bp->l_eor = log->eor;
1355
1356                 /* if current page is full, move on to next page */
1357                 if (log->eor >= LOGPSIZE - LOGPTLRSIZE)
1358                         lmNextPage(log);
1359
1360                 /*
1361                  * initialize log syncpoint
1362                  */
1363                 /*
1364                  * write the first SYNCPT record with syncpoint = 0
1365                  * (i.e., log redo up to HERE !);
1366                  * remove current page from lbm write queue at end of pageout
1367                  * (to write log superblock update), but do not release to
1368                  * freelist;
1369                  */
1370                 lrd.logtid = 0;
1371                 lrd.backchain = 0;
1372                 lrd.type = cpu_to_le16(LOG_SYNCPT);
1373                 lrd.length = 0;
1374                 lrd.log.syncpt.sync = 0;
1375                 lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1376                 bp = log->bp;
1377                 bp->l_ceor = bp->l_eor;
1378                 lp = (struct logpage *) bp->l_ldata;
1379                 lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1380                 lbmWrite(log, bp, lbmWRITE | lbmSYNC, 0);
1381                 if ((rc = lbmIOWait(bp, 0)))
1382                         goto errout30;
1383
1384                 /*
1385                  * update/write superblock
1386                  */
1387                 logsuper->state = cpu_to_le32(LOGMOUNT);
1388                 log->serial = le32_to_cpu(logsuper->serial) + 1;
1389                 logsuper->serial = cpu_to_le32(log->serial);
1390                 lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1391                 if ((rc = lbmIOWait(bpsuper, lbmFREE)))
1392                         goto errout30;
1393         }
1394
1395         /* initialize logsync parameters */
1396         log->logsize = (log->size - 2) << L2LOGPSIZE;
1397         log->lsn = lsn;
1398         log->syncpt = lsn;
1399         log->sync = log->syncpt;
1400         log->nextsync = LOGSYNC_DELTA(log->logsize);
1401
1402         jfs_info("lmLogInit: lsn:0x%x syncpt:0x%x sync:0x%x",
1403                  log->lsn, log->syncpt, log->sync);
1404
1405         /*
1406          * initialize for lazy/group commit
1407          */
1408         log->clsn = lsn;
1409
1410         return 0;
1411
1412         /*
1413          *      unwind on error
1414          */
1415       errout30:         /* release log page */
1416         log->wqueue = NULL;
1417         bp->l_wqnext = NULL;
1418         lbmFree(bp);
1419
1420       errout20:         /* release log superblock */
1421         lbmFree(bpsuper);
1422
1423       errout10:         /* unwind lbmLogInit() */
1424         lbmLogShutdown(log);
1425
1426         jfs_warn("lmLogInit: exit(%d)", rc);
1427         return rc;
1428 }
1429
1430
1431 /*
1432  * NAME:        lmLogClose()
1433  *
1434  * FUNCTION:    remove file system <ipmnt> from active list of log <iplog>
1435  *              and close it on last close.
1436  *
1437  * PARAMETER:   sb      - superblock
1438  *
1439  * RETURN:      errors from subroutines
1440  *
1441  * serialization:
1442  */
1443 int lmLogClose(struct super_block *sb)
1444 {
1445         struct jfs_sb_info *sbi = JFS_SBI(sb);
1446         struct jfs_log *log = sbi->log;
1447         struct block_device *bdev;
1448         int rc = 0;
1449
1450         jfs_info("lmLogClose: log:0x%p", log);
1451
1452         mutex_lock(&jfs_log_mutex);
1453         LOG_LOCK(log);
1454         list_del(&sbi->log_list);
1455         LOG_UNLOCK(log);
1456         sbi->log = NULL;
1457
1458         /*
1459          * We need to make sure all of the "written" metapages
1460          * actually make it to disk
1461          */
1462         sync_blockdev(sb->s_bdev);
1463
1464         if (test_bit(log_INLINELOG, &log->flag)) {
1465                 /*
1466                  *      in-line log in host file system
1467                  */
1468                 rc = lmLogShutdown(log);
1469                 kfree(log);
1470                 goto out;
1471         }
1472
1473         if (!log->no_integrity)
1474                 lmLogFileSystem(log, sbi, 0);
1475
1476         if (!list_empty(&log->sb_list))
1477                 goto out;
1478
1479         /*
1480          * TODO: ensure that the dummy_log is in a state to allow
1481          * lbmLogShutdown to deallocate all the buffers and call
1482          * kfree against dummy_log.  For now, leave dummy_log & its
1483          * buffers in memory, and resuse if another no-integrity mount
1484          * is requested.
1485          */
1486         if (log->no_integrity)
1487                 goto out;
1488
1489         /*
1490          *      external log as separate logical volume
1491          */
1492         list_del(&log->journal_list);
1493         bdev = log->bdev;
1494         rc = lmLogShutdown(log);
1495
1496         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1497
1498         kfree(log);
1499
1500       out:
1501         mutex_unlock(&jfs_log_mutex);
1502         jfs_info("lmLogClose: exit(%d)", rc);
1503         return rc;
1504 }
1505
1506
1507 /*
1508  * NAME:        jfs_flush_journal()
1509  *
1510  * FUNCTION:    initiate write of any outstanding transactions to the journal
1511  *              and optionally wait until they are all written to disk
1512  *
1513  *              wait == 0  flush until latest txn is committed, don't wait
1514  *              wait == 1  flush until latest txn is committed, wait
1515  *              wait > 1   flush until all txn's are complete, wait
1516  */
1517 void jfs_flush_journal(struct jfs_log *log, int wait)
1518 {
1519         int i;
1520         struct tblock *target = NULL;
1521
1522         /* jfs_write_inode may call us during read-only mount */
1523         if (!log)
1524                 return;
1525
1526         jfs_info("jfs_flush_journal: log:0x%p wait=%d", log, wait);
1527
1528         LOGGC_LOCK(log);
1529
1530         if (!list_empty(&log->cqueue)) {
1531                 /*
1532                  * This ensures that we will keep writing to the journal as long
1533                  * as there are unwritten commit records
1534                  */
1535                 target = list_entry(log->cqueue.prev, struct tblock, cqueue);
1536
1537                 if (test_bit(log_FLUSH, &log->flag)) {
1538                         /*
1539                          * We're already flushing.
1540                          * if flush_tblk is NULL, we are flushing everything,
1541                          * so leave it that way.  Otherwise, update it to the
1542                          * latest transaction
1543                          */
1544                         if (log->flush_tblk)
1545                                 log->flush_tblk = target;
1546                 } else {
1547                         /* Only flush until latest transaction is committed */
1548                         log->flush_tblk = target;
1549                         set_bit(log_FLUSH, &log->flag);
1550
1551                         /*
1552                          * Initiate I/O on outstanding transactions
1553                          */
1554                         if (!(log->cflag & logGC_PAGEOUT)) {
1555                                 log->cflag |= logGC_PAGEOUT;
1556                                 lmGCwrite(log, 0);
1557                         }
1558                 }
1559         }
1560         if ((wait > 1) || test_bit(log_SYNCBARRIER, &log->flag)) {
1561                 /* Flush until all activity complete */
1562                 set_bit(log_FLUSH, &log->flag);
1563                 log->flush_tblk = NULL;
1564         }
1565
1566         if (wait && target && !(target->flag & tblkGC_COMMITTED)) {
1567                 DECLARE_WAITQUEUE(__wait, current);
1568
1569                 add_wait_queue(&target->gcwait, &__wait);
1570                 set_current_state(TASK_UNINTERRUPTIBLE);
1571                 LOGGC_UNLOCK(log);
1572                 schedule();
1573                 LOGGC_LOCK(log);
1574                 remove_wait_queue(&target->gcwait, &__wait);
1575         }
1576         LOGGC_UNLOCK(log);
1577
1578         if (wait < 2)
1579                 return;
1580
1581         write_special_inodes(log, filemap_fdatawrite);
1582
1583         /*
1584          * If there was recent activity, we may need to wait
1585          * for the lazycommit thread to catch up
1586          */
1587         if ((!list_empty(&log->cqueue)) || !list_empty(&log->synclist)) {
1588                 for (i = 0; i < 200; i++) {     /* Too much? */
1589                         msleep(250);
1590                         write_special_inodes(log, filemap_fdatawrite);
1591                         if (list_empty(&log->cqueue) &&
1592                             list_empty(&log->synclist))
1593                                 break;
1594                 }
1595         }
1596         assert(list_empty(&log->cqueue));
1597
1598 #ifdef CONFIG_JFS_DEBUG
1599         if (!list_empty(&log->synclist)) {
1600                 struct logsyncblk *lp;
1601
1602                 printk(KERN_ERR "jfs_flush_journal: synclist not empty\n");
1603                 list_for_each_entry(lp, &log->synclist, synclist) {
1604                         if (lp->xflag & COMMIT_PAGE) {
1605                                 struct metapage *mp = (struct metapage *)lp;
1606                                 print_hex_dump(KERN_ERR, "metapage: ",
1607                                                DUMP_PREFIX_ADDRESS, 16, 4,
1608                                                mp, sizeof(struct metapage), 0);
1609                                 print_hex_dump(KERN_ERR, "page: ",
1610                                                DUMP_PREFIX_ADDRESS, 16,
1611                                                sizeof(long), mp->page,
1612                                                sizeof(struct page), 0);
1613                         } else
1614                                 print_hex_dump(KERN_ERR, "tblock:",
1615                                                DUMP_PREFIX_ADDRESS, 16, 4,
1616                                                lp, sizeof(struct tblock), 0);
1617                 }
1618         }
1619 #else
1620         WARN_ON(!list_empty(&log->synclist));
1621 #endif
1622         clear_bit(log_FLUSH, &log->flag);
1623 }
1624
1625 /*
1626  * NAME:        lmLogShutdown()
1627  *
1628  * FUNCTION:    log shutdown at last LogClose().
1629  *
1630  *              write log syncpt record.
1631  *              update super block to set redone flag to 0.
1632  *
1633  * PARAMETER:   log     - log inode
1634  *
1635  * RETURN:      0       - success
1636  *
1637  * serialization: single last close thread
1638  */
1639 int lmLogShutdown(struct jfs_log * log)
1640 {
1641         int rc;
1642         struct lrd lrd;
1643         int lsn;
1644         struct logsuper *logsuper;
1645         struct lbuf *bpsuper;
1646         struct lbuf *bp;
1647         struct logpage *lp;
1648
1649         jfs_info("lmLogShutdown: log:0x%p", log);
1650
1651         jfs_flush_journal(log, 2);
1652
1653         /*
1654          * write the last SYNCPT record with syncpoint = 0
1655          * (i.e., log redo up to HERE !)
1656          */
1657         lrd.logtid = 0;
1658         lrd.backchain = 0;
1659         lrd.type = cpu_to_le16(LOG_SYNCPT);
1660         lrd.length = 0;
1661         lrd.log.syncpt.sync = 0;
1662
1663         lsn = lmWriteRecord(log, NULL, &lrd, NULL);
1664         bp = log->bp;
1665         lp = (struct logpage *) bp->l_ldata;
1666         lp->h.eor = lp->t.eor = cpu_to_le16(bp->l_eor);
1667         lbmWrite(log, log->bp, lbmWRITE | lbmRELEASE | lbmSYNC, 0);
1668         lbmIOWait(log->bp, lbmFREE);
1669         log->bp = NULL;
1670
1671         /*
1672          * synchronous update log superblock
1673          * mark log state as shutdown cleanly
1674          * (i.e., Log does not need to be replayed).
1675          */
1676         if ((rc = lbmRead(log, 1, &bpsuper)))
1677                 goto out;
1678
1679         logsuper = (struct logsuper *) bpsuper->l_ldata;
1680         logsuper->state = cpu_to_le32(LOGREDONE);
1681         logsuper->end = cpu_to_le32(lsn);
1682         lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1683         rc = lbmIOWait(bpsuper, lbmFREE);
1684
1685         jfs_info("lmLogShutdown: lsn:0x%x page:%d eor:%d",
1686                  lsn, log->page, log->eor);
1687
1688       out:
1689         /*
1690          * shutdown per log i/o
1691          */
1692         lbmLogShutdown(log);
1693
1694         if (rc) {
1695                 jfs_warn("lmLogShutdown: exit(%d)", rc);
1696         }
1697         return rc;
1698 }
1699
1700
1701 /*
1702  * NAME:        lmLogFileSystem()
1703  *
1704  * FUNCTION:    insert (<activate> = true)/remove (<activate> = false)
1705  *      file system into/from log active file system list.
1706  *
1707  * PARAMETE:    log     - pointer to logs inode.
1708  *              fsdev   - kdev_t of filesystem.
1709  *              serial  - pointer to returned log serial number
1710  *              activate - insert/remove device from active list.
1711  *
1712  * RETURN:      0       - success
1713  *              errors returned by vms_iowait().
1714  */
1715 static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi,
1716                            int activate)
1717 {
1718         int rc = 0;
1719         int i;
1720         struct logsuper *logsuper;
1721         struct lbuf *bpsuper;
1722         uuid_t *uuid = &sbi->uuid;
1723
1724         /*
1725          * insert/remove file system device to log active file system list.
1726          */
1727         if ((rc = lbmRead(log, 1, &bpsuper)))
1728                 return rc;
1729
1730         logsuper = (struct logsuper *) bpsuper->l_ldata;
1731         if (activate) {
1732                 for (i = 0; i < MAX_ACTIVE; i++)
1733                         if (uuid_is_null(&logsuper->active[i].uuid)) {
1734                                 uuid_copy(&logsuper->active[i].uuid, uuid);
1735                                 sbi->aggregate = i;
1736                                 break;
1737                         }
1738                 if (i == MAX_ACTIVE) {
1739                         jfs_warn("Too many file systems sharing journal!");
1740                         lbmFree(bpsuper);
1741                         return -EMFILE; /* Is there a better rc? */
1742                 }
1743         } else {
1744                 for (i = 0; i < MAX_ACTIVE; i++)
1745                         if (uuid_equal(&logsuper->active[i].uuid, uuid)) {
1746                                 uuid_copy(&logsuper->active[i].uuid,
1747                                           &uuid_null);
1748                                 break;
1749                         }
1750                 if (i == MAX_ACTIVE) {
1751                         jfs_warn("Somebody stomped on the journal!");
1752                         lbmFree(bpsuper);
1753                         return -EIO;
1754                 }
1755
1756         }
1757
1758         /*
1759          * synchronous write log superblock:
1760          *
1761          * write sidestream bypassing write queue:
1762          * at file system mount, log super block is updated for
1763          * activation of the file system before any log record
1764          * (MOUNT record) of the file system, and at file system
1765          * unmount, all meta data for the file system has been
1766          * flushed before log super block is updated for deactivation
1767          * of the file system.
1768          */
1769         lbmDirectWrite(log, bpsuper, lbmWRITE | lbmRELEASE | lbmSYNC);
1770         rc = lbmIOWait(bpsuper, lbmFREE);
1771
1772         return rc;
1773 }
1774
1775 /*
1776  *              log buffer manager (lbm)
1777  *              ------------------------
1778  *
1779  * special purpose buffer manager supporting log i/o requirements.
1780  *
1781  * per log write queue:
1782  * log pageout occurs in serial order by fifo write queue and
1783  * restricting to a single i/o in pregress at any one time.
1784  * a circular singly-linked list
1785  * (log->wrqueue points to the tail, and buffers are linked via
1786  * bp->wrqueue field), and
1787  * maintains log page in pageout ot waiting for pageout in serial pageout.
1788  */
1789
1790 /*
1791  *      lbmLogInit()
1792  *
1793  * initialize per log I/O setup at lmLogInit()
1794  */
1795 static int lbmLogInit(struct jfs_log * log)
1796 {                               /* log inode */
1797         int i;
1798         struct lbuf *lbuf;
1799
1800         jfs_info("lbmLogInit: log:0x%p", log);
1801
1802         /* initialize current buffer cursor */
1803         log->bp = NULL;
1804
1805         /* initialize log device write queue */
1806         log->wqueue = NULL;
1807
1808         /*
1809          * Each log has its own buffer pages allocated to it.  These are
1810          * not managed by the page cache.  This ensures that a transaction
1811          * writing to the log does not block trying to allocate a page from
1812          * the page cache (for the log).  This would be bad, since page
1813          * allocation waits on the kswapd thread that may be committing inodes
1814          * which would cause log activity.  Was that clear?  I'm trying to
1815          * avoid deadlock here.
1816          */
1817         init_waitqueue_head(&log->free_wait);
1818
1819         log->lbuf_free = NULL;
1820
1821         for (i = 0; i < LOGPAGES;) {
1822                 char *buffer;
1823                 uint offset;
1824                 struct page *page = alloc_page(GFP_KERNEL | __GFP_ZERO);
1825
1826                 if (!page)
1827                         goto error;
1828                 buffer = page_address(page);
1829                 for (offset = 0; offset < PAGE_SIZE; offset += LOGPSIZE) {
1830                         lbuf = kmalloc(sizeof(struct lbuf), GFP_KERNEL);
1831                         if (lbuf == NULL) {
1832                                 if (offset == 0)
1833                                         __free_page(page);
1834                                 goto error;
1835                         }
1836                         if (offset) /* we already have one reference */
1837                                 get_page(page);
1838                         lbuf->l_offset = offset;
1839                         lbuf->l_ldata = buffer + offset;
1840                         lbuf->l_page = page;
1841                         lbuf->l_log = log;
1842                         init_waitqueue_head(&lbuf->l_ioevent);
1843
1844                         lbuf->l_freelist = log->lbuf_free;
1845                         log->lbuf_free = lbuf;
1846                         i++;
1847                 }
1848         }
1849
1850         return (0);
1851
1852       error:
1853         lbmLogShutdown(log);
1854         return -ENOMEM;
1855 }
1856
1857
1858 /*
1859  *      lbmLogShutdown()
1860  *
1861  * finalize per log I/O setup at lmLogShutdown()
1862  */
1863 static void lbmLogShutdown(struct jfs_log * log)
1864 {
1865         struct lbuf *lbuf;
1866
1867         jfs_info("lbmLogShutdown: log:0x%p", log);
1868
1869         lbuf = log->lbuf_free;
1870         while (lbuf) {
1871                 struct lbuf *next = lbuf->l_freelist;
1872                 __free_page(lbuf->l_page);
1873                 kfree(lbuf);
1874                 lbuf = next;
1875         }
1876 }
1877
1878
1879 /*
1880  *      lbmAllocate()
1881  *
1882  * allocate an empty log buffer
1883  */
1884 static struct lbuf *lbmAllocate(struct jfs_log * log, int pn)
1885 {
1886         struct lbuf *bp;
1887         unsigned long flags;
1888
1889         /*
1890          * recycle from log buffer freelist if any
1891          */
1892         LCACHE_LOCK(flags);
1893         LCACHE_SLEEP_COND(log->free_wait, (bp = log->lbuf_free), flags);
1894         log->lbuf_free = bp->l_freelist;
1895         LCACHE_UNLOCK(flags);
1896
1897         bp->l_flag = 0;
1898
1899         bp->l_wqnext = NULL;
1900         bp->l_freelist = NULL;
1901
1902         bp->l_pn = pn;
1903         bp->l_blkno = log->base + (pn << (L2LOGPSIZE - log->l2bsize));
1904         bp->l_ceor = 0;
1905
1906         return bp;
1907 }
1908
1909
1910 /*
1911  *      lbmFree()
1912  *
1913  * release a log buffer to freelist
1914  */
1915 static void lbmFree(struct lbuf * bp)
1916 {
1917         unsigned long flags;
1918
1919         LCACHE_LOCK(flags);
1920
1921         lbmfree(bp);
1922
1923         LCACHE_UNLOCK(flags);
1924 }
1925
1926 static void lbmfree(struct lbuf * bp)
1927 {
1928         struct jfs_log *log = bp->l_log;
1929
1930         assert(bp->l_wqnext == NULL);
1931
1932         /*
1933          * return the buffer to head of freelist
1934          */
1935         bp->l_freelist = log->lbuf_free;
1936         log->lbuf_free = bp;
1937
1938         wake_up(&log->free_wait);
1939         return;
1940 }
1941
1942
1943 /*
1944  * NAME:        lbmRedrive
1945  *
1946  * FUNCTION:    add a log buffer to the log redrive list
1947  *
1948  * PARAMETER:
1949  *      bp      - log buffer
1950  *
1951  * NOTES:
1952  *      Takes log_redrive_lock.
1953  */
1954 static inline void lbmRedrive(struct lbuf *bp)
1955 {
1956         unsigned long flags;
1957
1958         spin_lock_irqsave(&log_redrive_lock, flags);
1959         bp->l_redrive_next = log_redrive_list;
1960         log_redrive_list = bp;
1961         spin_unlock_irqrestore(&log_redrive_lock, flags);
1962
1963         wake_up_process(jfsIOthread);
1964 }
1965
1966
1967 /*
1968  *      lbmRead()
1969  */
1970 static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
1971 {
1972         struct bio *bio;
1973         struct lbuf *bp;
1974
1975         /*
1976          * allocate a log buffer
1977          */
1978         *bpp = bp = lbmAllocate(log, pn);
1979         jfs_info("lbmRead: bp:0x%p pn:0x%x", bp, pn);
1980
1981         bp->l_flag |= lbmREAD;
1982
1983         bio = bio_alloc(GFP_NOFS, 1);
1984
1985         bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
1986         bio_set_dev(bio, log->bdev);
1987
1988         bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
1989         BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
1990
1991         bio->bi_end_io = lbmIODone;
1992         bio->bi_private = bp;
1993         bio->bi_opf = REQ_OP_READ;
1994         /*check if journaling to disk has been disabled*/
1995         if (log->no_integrity) {
1996                 bio->bi_iter.bi_size = 0;
1997                 lbmIODone(bio);
1998         } else {
1999                 submit_bio(bio);
2000         }
2001
2002         wait_event(bp->l_ioevent, (bp->l_flag != lbmREAD));
2003
2004         return 0;
2005 }
2006
2007
2008 /*
2009  *      lbmWrite()
2010  *
2011  * buffer at head of pageout queue stays after completion of
2012  * partial-page pageout and redriven by explicit initiation of
2013  * pageout by caller until full-page pageout is completed and
2014  * released.
2015  *
2016  * device driver i/o done redrives pageout of new buffer at
2017  * head of pageout queue when current buffer at head of pageout
2018  * queue is released at the completion of its full-page pageout.
2019  *
2020  * LOGGC_LOCK() serializes lbmWrite() by lmNextPage() and lmGroupCommit().
2021  * LCACHE_LOCK() serializes xflag between lbmWrite() and lbmIODone()
2022  */
2023 static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag,
2024                      int cant_block)
2025 {
2026         struct lbuf *tail;
2027         unsigned long flags;
2028
2029         jfs_info("lbmWrite: bp:0x%p flag:0x%x pn:0x%x", bp, flag, bp->l_pn);
2030
2031         /* map the logical block address to physical block address */
2032         bp->l_blkno =
2033             log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2034
2035         LCACHE_LOCK(flags);             /* disable+lock */
2036
2037         /*
2038          * initialize buffer for device driver
2039          */
2040         bp->l_flag = flag;
2041
2042         /*
2043          *      insert bp at tail of write queue associated with log
2044          *
2045          * (request is either for bp already/currently at head of queue
2046          * or new bp to be inserted at tail)
2047          */
2048         tail = log->wqueue;
2049
2050         /* is buffer not already on write queue ? */
2051         if (bp->l_wqnext == NULL) {
2052                 /* insert at tail of wqueue */
2053                 if (tail == NULL) {
2054                         log->wqueue = bp;
2055                         bp->l_wqnext = bp;
2056                 } else {
2057                         log->wqueue = bp;
2058                         bp->l_wqnext = tail->l_wqnext;
2059                         tail->l_wqnext = bp;
2060                 }
2061
2062                 tail = bp;
2063         }
2064
2065         /* is buffer at head of wqueue and for write ? */
2066         if ((bp != tail->l_wqnext) || !(flag & lbmWRITE)) {
2067                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2068                 return;
2069         }
2070
2071         LCACHE_UNLOCK(flags);   /* unlock+enable */
2072
2073         if (cant_block)
2074                 lbmRedrive(bp);
2075         else if (flag & lbmSYNC)
2076                 lbmStartIO(bp);
2077         else {
2078                 LOGGC_UNLOCK(log);
2079                 lbmStartIO(bp);
2080                 LOGGC_LOCK(log);
2081         }
2082 }
2083
2084
2085 /*
2086  *      lbmDirectWrite()
2087  *
2088  * initiate pageout bypassing write queue for sidestream
2089  * (e.g., log superblock) write;
2090  */
2091 static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag)
2092 {
2093         jfs_info("lbmDirectWrite: bp:0x%p flag:0x%x pn:0x%x",
2094                  bp, flag, bp->l_pn);
2095
2096         /*
2097          * initialize buffer for device driver
2098          */
2099         bp->l_flag = flag | lbmDIRECT;
2100
2101         /* map the logical block address to physical block address */
2102         bp->l_blkno =
2103             log->base + (bp->l_pn << (L2LOGPSIZE - log->l2bsize));
2104
2105         /*
2106          *      initiate pageout of the page
2107          */
2108         lbmStartIO(bp);
2109 }
2110
2111
2112 /*
2113  * NAME:        lbmStartIO()
2114  *
2115  * FUNCTION:    Interface to DD strategy routine
2116  *
2117  * RETURN:      none
2118  *
2119  * serialization: LCACHE_LOCK() is NOT held during log i/o;
2120  */
2121 static void lbmStartIO(struct lbuf * bp)
2122 {
2123         struct bio *bio;
2124         struct jfs_log *log = bp->l_log;
2125
2126         jfs_info("lbmStartIO");
2127
2128         bio = bio_alloc(GFP_NOFS, 1);
2129         bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
2130         bio_set_dev(bio, log->bdev);
2131
2132         bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
2133         BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
2134
2135         bio->bi_end_io = lbmIODone;
2136         bio->bi_private = bp;
2137         bio->bi_opf = REQ_OP_WRITE | REQ_SYNC;
2138
2139         /* check if journaling to disk has been disabled */
2140         if (log->no_integrity) {
2141                 bio->bi_iter.bi_size = 0;
2142                 lbmIODone(bio);
2143         } else {
2144                 submit_bio(bio);
2145                 INCREMENT(lmStat.submitted);
2146         }
2147 }
2148
2149
2150 /*
2151  *      lbmIOWait()
2152  */
2153 static int lbmIOWait(struct lbuf * bp, int flag)
2154 {
2155         unsigned long flags;
2156         int rc = 0;
2157
2158         jfs_info("lbmIOWait1: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2159
2160         LCACHE_LOCK(flags);             /* disable+lock */
2161
2162         LCACHE_SLEEP_COND(bp->l_ioevent, (bp->l_flag & lbmDONE), flags);
2163
2164         rc = (bp->l_flag & lbmERROR) ? -EIO : 0;
2165
2166         if (flag & lbmFREE)
2167                 lbmfree(bp);
2168
2169         LCACHE_UNLOCK(flags);   /* unlock+enable */
2170
2171         jfs_info("lbmIOWait2: bp:0x%p flag:0x%x:0x%x", bp, bp->l_flag, flag);
2172         return rc;
2173 }
2174
2175 /*
2176  *      lbmIODone()
2177  *
2178  * executed at INTIODONE level
2179  */
2180 static void lbmIODone(struct bio *bio)
2181 {
2182         struct lbuf *bp = bio->bi_private;
2183         struct lbuf *nextbp, *tail;
2184         struct jfs_log *log;
2185         unsigned long flags;
2186
2187         /*
2188          * get back jfs buffer bound to the i/o buffer
2189          */
2190         jfs_info("lbmIODone: bp:0x%p flag:0x%x", bp, bp->l_flag);
2191
2192         LCACHE_LOCK(flags);             /* disable+lock */
2193
2194         bp->l_flag |= lbmDONE;
2195
2196         if (bio->bi_status) {
2197                 bp->l_flag |= lbmERROR;
2198
2199                 jfs_err("lbmIODone: I/O error in JFS log");
2200         }
2201
2202         bio_put(bio);
2203
2204         /*
2205          *      pagein completion
2206          */
2207         if (bp->l_flag & lbmREAD) {
2208                 bp->l_flag &= ~lbmREAD;
2209
2210                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2211
2212                 /* wakeup I/O initiator */
2213                 LCACHE_WAKEUP(&bp->l_ioevent);
2214
2215                 return;
2216         }
2217
2218         /*
2219          *      pageout completion
2220          *
2221          * the bp at the head of write queue has completed pageout.
2222          *
2223          * if single-commit/full-page pageout, remove the current buffer
2224          * from head of pageout queue, and redrive pageout with
2225          * the new buffer at head of pageout queue;
2226          * otherwise, the partial-page pageout buffer stays at
2227          * the head of pageout queue to be redriven for pageout
2228          * by lmGroupCommit() until full-page pageout is completed.
2229          */
2230         bp->l_flag &= ~lbmWRITE;
2231         INCREMENT(lmStat.pagedone);
2232
2233         /* update committed lsn */
2234         log = bp->l_log;
2235         log->clsn = (bp->l_pn << L2LOGPSIZE) + bp->l_ceor;
2236
2237         if (bp->l_flag & lbmDIRECT) {
2238                 LCACHE_WAKEUP(&bp->l_ioevent);
2239                 LCACHE_UNLOCK(flags);
2240                 return;
2241         }
2242
2243         tail = log->wqueue;
2244
2245         /* single element queue */
2246         if (bp == tail) {
2247                 /* remove head buffer of full-page pageout
2248                  * from log device write queue
2249                  */
2250                 if (bp->l_flag & lbmRELEASE) {
2251                         log->wqueue = NULL;
2252                         bp->l_wqnext = NULL;
2253                 }
2254         }
2255         /* multi element queue */
2256         else {
2257                 /* remove head buffer of full-page pageout
2258                  * from log device write queue
2259                  */
2260                 if (bp->l_flag & lbmRELEASE) {
2261                         nextbp = tail->l_wqnext = bp->l_wqnext;
2262                         bp->l_wqnext = NULL;
2263
2264                         /*
2265                          * redrive pageout of next page at head of write queue:
2266                          * redrive next page without any bound tblk
2267                          * (i.e., page w/o any COMMIT records), or
2268                          * first page of new group commit which has been
2269                          * queued after current page (subsequent pageout
2270                          * is performed synchronously, except page without
2271                          * any COMMITs) by lmGroupCommit() as indicated
2272                          * by lbmWRITE flag;
2273                          */
2274                         if (nextbp->l_flag & lbmWRITE) {
2275                                 /*
2276                                  * We can't do the I/O at interrupt time.
2277                                  * The jfsIO thread can do it
2278                                  */
2279                                 lbmRedrive(nextbp);
2280                         }
2281                 }
2282         }
2283
2284         /*
2285          *      synchronous pageout:
2286          *
2287          * buffer has not necessarily been removed from write queue
2288          * (e.g., synchronous write of partial-page with COMMIT):
2289          * leave buffer for i/o initiator to dispose
2290          */
2291         if (bp->l_flag & lbmSYNC) {
2292                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2293
2294                 /* wakeup I/O initiator */
2295                 LCACHE_WAKEUP(&bp->l_ioevent);
2296         }
2297
2298         /*
2299          *      Group Commit pageout:
2300          */
2301         else if (bp->l_flag & lbmGC) {
2302                 LCACHE_UNLOCK(flags);
2303                 lmPostGC(bp);
2304         }
2305
2306         /*
2307          *      asynchronous pageout:
2308          *
2309          * buffer must have been removed from write queue:
2310          * insert buffer at head of freelist where it can be recycled
2311          */
2312         else {
2313                 assert(bp->l_flag & lbmRELEASE);
2314                 assert(bp->l_flag & lbmFREE);
2315                 lbmfree(bp);
2316
2317                 LCACHE_UNLOCK(flags);   /* unlock+enable */
2318         }
2319 }
2320
2321 int jfsIOWait(void *arg)
2322 {
2323         struct lbuf *bp;
2324
2325         do {
2326                 spin_lock_irq(&log_redrive_lock);
2327                 while ((bp = log_redrive_list)) {
2328                         log_redrive_list = bp->l_redrive_next;
2329                         bp->l_redrive_next = NULL;
2330                         spin_unlock_irq(&log_redrive_lock);
2331                         lbmStartIO(bp);
2332                         spin_lock_irq(&log_redrive_lock);
2333                 }
2334
2335                 if (freezing(current)) {
2336                         spin_unlock_irq(&log_redrive_lock);
2337                         try_to_freeze();
2338                 } else {
2339                         set_current_state(TASK_INTERRUPTIBLE);
2340                         spin_unlock_irq(&log_redrive_lock);
2341                         schedule();
2342                 }
2343         } while (!kthread_should_stop());
2344
2345         jfs_info("jfsIOWait being killed!");
2346         return 0;
2347 }
2348
2349 /*
2350  * NAME:        lmLogFormat()/jfs_logform()
2351  *
2352  * FUNCTION:    format file system log
2353  *
2354  * PARAMETERS:
2355  *      log     - volume log
2356  *      logAddress - start address of log space in FS block
2357  *      logSize - length of log space in FS block;
2358  *
2359  * RETURN:      0       - success
2360  *              -EIO    - i/o error
2361  *
2362  * XXX: We're synchronously writing one page at a time.  This needs to
2363  *      be improved by writing multiple pages at once.
2364  */
2365 int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize)
2366 {
2367         int rc = -EIO;
2368         struct jfs_sb_info *sbi;
2369         struct logsuper *logsuper;
2370         struct logpage *lp;
2371         int lspn;               /* log sequence page number */
2372         struct lrd *lrd_ptr;
2373         int npages = 0;
2374         struct lbuf *bp;
2375
2376         jfs_info("lmLogFormat: logAddress:%Ld logSize:%d",
2377                  (long long)logAddress, logSize);
2378
2379         sbi = list_entry(log->sb_list.next, struct jfs_sb_info, log_list);
2380
2381         /* allocate a log buffer */
2382         bp = lbmAllocate(log, 1);
2383
2384         npages = logSize >> sbi->l2nbperpage;
2385
2386         /*
2387          *      log space:
2388          *
2389          * page 0 - reserved;
2390          * page 1 - log superblock;
2391          * page 2 - log data page: A SYNC log record is written
2392          *          into this page at logform time;
2393          * pages 3-N - log data page: set to empty log data pages;
2394          */
2395         /*
2396          *      init log superblock: log page 1
2397          */
2398         logsuper = (struct logsuper *) bp->l_ldata;
2399
2400         logsuper->magic = cpu_to_le32(LOGMAGIC);
2401         logsuper->version = cpu_to_le32(LOGVERSION);
2402         logsuper->state = cpu_to_le32(LOGREDONE);
2403         logsuper->flag = cpu_to_le32(sbi->mntflag);     /* ? */
2404         logsuper->size = cpu_to_le32(npages);
2405         logsuper->bsize = cpu_to_le32(sbi->bsize);
2406         logsuper->l2bsize = cpu_to_le32(sbi->l2bsize);
2407         logsuper->end = cpu_to_le32(2 * LOGPSIZE + LOGPHDRSIZE + LOGRDSIZE);
2408
2409         bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2410         bp->l_blkno = logAddress + sbi->nbperpage;
2411         lbmStartIO(bp);
2412         if ((rc = lbmIOWait(bp, 0)))
2413                 goto exit;
2414
2415         /*
2416          *      init pages 2 to npages-1 as log data pages:
2417          *
2418          * log page sequence number (lpsn) initialization:
2419          *
2420          * pn:   0     1     2     3                 n-1
2421          *       +-----+-----+=====+=====+===.....===+=====+
2422          * lspn:             N-1   0     1           N-2
2423          *                   <--- N page circular file ---->
2424          *
2425          * the N (= npages-2) data pages of the log is maintained as
2426          * a circular file for the log records;
2427          * lpsn grows by 1 monotonically as each log page is written
2428          * to the circular file of the log;
2429          * and setLogpage() will not reset the page number even if
2430          * the eor is equal to LOGPHDRSIZE. In order for binary search
2431          * still work in find log end process, we have to simulate the
2432          * log wrap situation at the log format time.
2433          * The 1st log page written will have the highest lpsn. Then
2434          * the succeeding log pages will have ascending order of
2435          * the lspn starting from 0, ... (N-2)
2436          */
2437         lp = (struct logpage *) bp->l_ldata;
2438         /*
2439          * initialize 1st log page to be written: lpsn = N - 1,
2440          * write a SYNCPT log record is written to this page
2441          */
2442         lp->h.page = lp->t.page = cpu_to_le32(npages - 3);
2443         lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE + LOGRDSIZE);
2444
2445         lrd_ptr = (struct lrd *) &lp->data;
2446         lrd_ptr->logtid = 0;
2447         lrd_ptr->backchain = 0;
2448         lrd_ptr->type = cpu_to_le16(LOG_SYNCPT);
2449         lrd_ptr->length = 0;
2450         lrd_ptr->log.syncpt.sync = 0;
2451
2452         bp->l_blkno += sbi->nbperpage;
2453         bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2454         lbmStartIO(bp);
2455         if ((rc = lbmIOWait(bp, 0)))
2456                 goto exit;
2457
2458         /*
2459          *      initialize succeeding log pages: lpsn = 0, 1, ..., (N-2)
2460          */
2461         for (lspn = 0; lspn < npages - 3; lspn++) {
2462                 lp->h.page = lp->t.page = cpu_to_le32(lspn);
2463                 lp->h.eor = lp->t.eor = cpu_to_le16(LOGPHDRSIZE);
2464
2465                 bp->l_blkno += sbi->nbperpage;
2466                 bp->l_flag = lbmWRITE | lbmSYNC | lbmDIRECT;
2467                 lbmStartIO(bp);
2468                 if ((rc = lbmIOWait(bp, 0)))
2469                         goto exit;
2470         }
2471
2472         rc = 0;
2473 exit:
2474         /*
2475          *      finalize log
2476          */
2477         /* release the buffer */
2478         lbmFree(bp);
2479
2480         return rc;
2481 }
2482
2483 #ifdef CONFIG_JFS_STATISTICS
2484 int jfs_lmstats_proc_show(struct seq_file *m, void *v)
2485 {
2486         seq_printf(m,
2487                        "JFS Logmgr stats\n"
2488                        "================\n"
2489                        "commits = %d\n"
2490                        "writes submitted = %d\n"
2491                        "writes completed = %d\n"
2492                        "full pages submitted = %d\n"
2493                        "partial pages submitted = %d\n",
2494                        lmStat.commit,
2495                        lmStat.submitted,
2496                        lmStat.pagedone,
2497                        lmStat.full_page,
2498                        lmStat.partial_page);
2499         return 0;
2500 }
2501 #endif /* CONFIG_JFS_STATISTICS */