[XFS] Cleanup maxrecs calculation.
[linux-2.6.git] / fs / xfs / xfs_log_recover.c
1 /*
2  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_dir2.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_error.h"
31 #include "xfs_bmap_btree.h"
32 #include "xfs_alloc_btree.h"
33 #include "xfs_ialloc_btree.h"
34 #include "xfs_dir2_sf.h"
35 #include "xfs_attr_sf.h"
36 #include "xfs_dinode.h"
37 #include "xfs_inode.h"
38 #include "xfs_inode_item.h"
39 #include "xfs_imap.h"
40 #include "xfs_alloc.h"
41 #include "xfs_ialloc.h"
42 #include "xfs_log_priv.h"
43 #include "xfs_buf_item.h"
44 #include "xfs_log_recover.h"
45 #include "xfs_extfree_item.h"
46 #include "xfs_trans_priv.h"
47 #include "xfs_quota.h"
48 #include "xfs_rw.h"
49 #include "xfs_utils.h"
50
51 STATIC int      xlog_find_zeroed(xlog_t *, xfs_daddr_t *);
52 STATIC int      xlog_clear_stale_blocks(xlog_t *, xfs_lsn_t);
53 STATIC void     xlog_recover_insert_item_backq(xlog_recover_item_t **q,
54                                                xlog_recover_item_t *item);
55 #if defined(DEBUG)
56 STATIC void     xlog_recover_check_summary(xlog_t *);
57 STATIC void     xlog_recover_check_ail(xfs_mount_t *, xfs_log_item_t *, int);
58 #else
59 #define xlog_recover_check_summary(log)
60 #define xlog_recover_check_ail(mp, lip, gen)
61 #endif
62
63
64 /*
65  * Sector aligned buffer routines for buffer create/read/write/access
66  */
67
68 #define XLOG_SECTOR_ROUNDUP_BBCOUNT(log, bbs)   \
69         ( ((log)->l_sectbb_mask && (bbs & (log)->l_sectbb_mask)) ? \
70         ((bbs + (log)->l_sectbb_mask + 1) & ~(log)->l_sectbb_mask) : (bbs) )
71 #define XLOG_SECTOR_ROUNDDOWN_BLKNO(log, bno)   ((bno) & ~(log)->l_sectbb_mask)
72
73 xfs_buf_t *
74 xlog_get_bp(
75         xlog_t          *log,
76         int             num_bblks)
77 {
78         ASSERT(num_bblks > 0);
79
80         if (log->l_sectbb_log) {
81                 if (num_bblks > 1)
82                         num_bblks += XLOG_SECTOR_ROUNDUP_BBCOUNT(log, 1);
83                 num_bblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, num_bblks);
84         }
85         return xfs_buf_get_noaddr(BBTOB(num_bblks), log->l_mp->m_logdev_targp);
86 }
87
88 void
89 xlog_put_bp(
90         xfs_buf_t       *bp)
91 {
92         xfs_buf_free(bp);
93 }
94
95
96 /*
97  * nbblks should be uint, but oh well.  Just want to catch that 32-bit length.
98  */
99 int
100 xlog_bread(
101         xlog_t          *log,
102         xfs_daddr_t     blk_no,
103         int             nbblks,
104         xfs_buf_t       *bp)
105 {
106         int             error;
107
108         if (log->l_sectbb_log) {
109                 blk_no = XLOG_SECTOR_ROUNDDOWN_BLKNO(log, blk_no);
110                 nbblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, nbblks);
111         }
112
113         ASSERT(nbblks > 0);
114         ASSERT(BBTOB(nbblks) <= XFS_BUF_SIZE(bp));
115         ASSERT(bp);
116
117         XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
118         XFS_BUF_READ(bp);
119         XFS_BUF_BUSY(bp);
120         XFS_BUF_SET_COUNT(bp, BBTOB(nbblks));
121         XFS_BUF_SET_TARGET(bp, log->l_mp->m_logdev_targp);
122
123         xfsbdstrat(log->l_mp, bp);
124         error = xfs_iowait(bp);
125         if (error)
126                 xfs_ioerror_alert("xlog_bread", log->l_mp,
127                                   bp, XFS_BUF_ADDR(bp));
128         return error;
129 }
130
131 /*
132  * Write out the buffer at the given block for the given number of blocks.
133  * The buffer is kept locked across the write and is returned locked.
134  * This can only be used for synchronous log writes.
135  */
136 STATIC int
137 xlog_bwrite(
138         xlog_t          *log,
139         xfs_daddr_t     blk_no,
140         int             nbblks,
141         xfs_buf_t       *bp)
142 {
143         int             error;
144
145         if (log->l_sectbb_log) {
146                 blk_no = XLOG_SECTOR_ROUNDDOWN_BLKNO(log, blk_no);
147                 nbblks = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, nbblks);
148         }
149
150         ASSERT(nbblks > 0);
151         ASSERT(BBTOB(nbblks) <= XFS_BUF_SIZE(bp));
152
153         XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
154         XFS_BUF_ZEROFLAGS(bp);
155         XFS_BUF_BUSY(bp);
156         XFS_BUF_HOLD(bp);
157         XFS_BUF_PSEMA(bp, PRIBIO);
158         XFS_BUF_SET_COUNT(bp, BBTOB(nbblks));
159         XFS_BUF_SET_TARGET(bp, log->l_mp->m_logdev_targp);
160
161         if ((error = xfs_bwrite(log->l_mp, bp)))
162                 xfs_ioerror_alert("xlog_bwrite", log->l_mp,
163                                   bp, XFS_BUF_ADDR(bp));
164         return error;
165 }
166
167 STATIC xfs_caddr_t
168 xlog_align(
169         xlog_t          *log,
170         xfs_daddr_t     blk_no,
171         int             nbblks,
172         xfs_buf_t       *bp)
173 {
174         xfs_caddr_t     ptr;
175
176         if (!log->l_sectbb_log)
177                 return XFS_BUF_PTR(bp);
178
179         ptr = XFS_BUF_PTR(bp) + BBTOB((int)blk_no & log->l_sectbb_mask);
180         ASSERT(XFS_BUF_SIZE(bp) >=
181                 BBTOB(nbblks + (blk_no & log->l_sectbb_mask)));
182         return ptr;
183 }
184
185 #ifdef DEBUG
186 /*
187  * dump debug superblock and log record information
188  */
189 STATIC void
190 xlog_header_check_dump(
191         xfs_mount_t             *mp,
192         xlog_rec_header_t       *head)
193 {
194         int                     b;
195
196         cmn_err(CE_DEBUG, "%s:  SB : uuid = ", __func__);
197         for (b = 0; b < 16; b++)
198                 cmn_err(CE_DEBUG, "%02x", ((uchar_t *)&mp->m_sb.sb_uuid)[b]);
199         cmn_err(CE_DEBUG, ", fmt = %d\n", XLOG_FMT);
200         cmn_err(CE_DEBUG, "    log : uuid = ");
201         for (b = 0; b < 16; b++)
202                 cmn_err(CE_DEBUG, "%02x",((uchar_t *)&head->h_fs_uuid)[b]);
203         cmn_err(CE_DEBUG, ", fmt = %d\n", be32_to_cpu(head->h_fmt));
204 }
205 #else
206 #define xlog_header_check_dump(mp, head)
207 #endif
208
209 /*
210  * check log record header for recovery
211  */
212 STATIC int
213 xlog_header_check_recover(
214         xfs_mount_t             *mp,
215         xlog_rec_header_t       *head)
216 {
217         ASSERT(be32_to_cpu(head->h_magicno) == XLOG_HEADER_MAGIC_NUM);
218
219         /*
220          * IRIX doesn't write the h_fmt field and leaves it zeroed
221          * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
222          * a dirty log created in IRIX.
223          */
224         if (unlikely(be32_to_cpu(head->h_fmt) != XLOG_FMT)) {
225                 xlog_warn(
226         "XFS: dirty log written in incompatible format - can't recover");
227                 xlog_header_check_dump(mp, head);
228                 XFS_ERROR_REPORT("xlog_header_check_recover(1)",
229                                  XFS_ERRLEVEL_HIGH, mp);
230                 return XFS_ERROR(EFSCORRUPTED);
231         } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
232                 xlog_warn(
233         "XFS: dirty log entry has mismatched uuid - can't recover");
234                 xlog_header_check_dump(mp, head);
235                 XFS_ERROR_REPORT("xlog_header_check_recover(2)",
236                                  XFS_ERRLEVEL_HIGH, mp);
237                 return XFS_ERROR(EFSCORRUPTED);
238         }
239         return 0;
240 }
241
242 /*
243  * read the head block of the log and check the header
244  */
245 STATIC int
246 xlog_header_check_mount(
247         xfs_mount_t             *mp,
248         xlog_rec_header_t       *head)
249 {
250         ASSERT(be32_to_cpu(head->h_magicno) == XLOG_HEADER_MAGIC_NUM);
251
252         if (uuid_is_nil(&head->h_fs_uuid)) {
253                 /*
254                  * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
255                  * h_fs_uuid is nil, we assume this log was last mounted
256                  * by IRIX and continue.
257                  */
258                 xlog_warn("XFS: nil uuid in log - IRIX style log");
259         } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
260                 xlog_warn("XFS: log has mismatched uuid - can't recover");
261                 xlog_header_check_dump(mp, head);
262                 XFS_ERROR_REPORT("xlog_header_check_mount",
263                                  XFS_ERRLEVEL_HIGH, mp);
264                 return XFS_ERROR(EFSCORRUPTED);
265         }
266         return 0;
267 }
268
269 STATIC void
270 xlog_recover_iodone(
271         struct xfs_buf  *bp)
272 {
273         xfs_mount_t     *mp;
274
275         ASSERT(XFS_BUF_FSPRIVATE(bp, void *));
276
277         if (XFS_BUF_GETERROR(bp)) {
278                 /*
279                  * We're not going to bother about retrying
280                  * this during recovery. One strike!
281                  */
282                 mp = XFS_BUF_FSPRIVATE(bp, xfs_mount_t *);
283                 xfs_ioerror_alert("xlog_recover_iodone",
284                                   mp, bp, XFS_BUF_ADDR(bp));
285                 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
286         }
287         XFS_BUF_SET_FSPRIVATE(bp, NULL);
288         XFS_BUF_CLR_IODONE_FUNC(bp);
289         xfs_biodone(bp);
290 }
291
292 /*
293  * This routine finds (to an approximation) the first block in the physical
294  * log which contains the given cycle.  It uses a binary search algorithm.
295  * Note that the algorithm can not be perfect because the disk will not
296  * necessarily be perfect.
297  */
298 STATIC int
299 xlog_find_cycle_start(
300         xlog_t          *log,
301         xfs_buf_t       *bp,
302         xfs_daddr_t     first_blk,
303         xfs_daddr_t     *last_blk,
304         uint            cycle)
305 {
306         xfs_caddr_t     offset;
307         xfs_daddr_t     mid_blk;
308         uint            mid_cycle;
309         int             error;
310
311         mid_blk = BLK_AVG(first_blk, *last_blk);
312         while (mid_blk != first_blk && mid_blk != *last_blk) {
313                 if ((error = xlog_bread(log, mid_blk, 1, bp)))
314                         return error;
315                 offset = xlog_align(log, mid_blk, 1, bp);
316                 mid_cycle = xlog_get_cycle(offset);
317                 if (mid_cycle == cycle) {
318                         *last_blk = mid_blk;
319                         /* last_half_cycle == mid_cycle */
320                 } else {
321                         first_blk = mid_blk;
322                         /* first_half_cycle == mid_cycle */
323                 }
324                 mid_blk = BLK_AVG(first_blk, *last_blk);
325         }
326         ASSERT((mid_blk == first_blk && mid_blk+1 == *last_blk) ||
327                (mid_blk == *last_blk && mid_blk-1 == first_blk));
328
329         return 0;
330 }
331
332 /*
333  * Check that the range of blocks does not contain the cycle number
334  * given.  The scan needs to occur from front to back and the ptr into the
335  * region must be updated since a later routine will need to perform another
336  * test.  If the region is completely good, we end up returning the same
337  * last block number.
338  *
339  * Set blkno to -1 if we encounter no errors.  This is an invalid block number
340  * since we don't ever expect logs to get this large.
341  */
342 STATIC int
343 xlog_find_verify_cycle(
344         xlog_t          *log,
345         xfs_daddr_t     start_blk,
346         int             nbblks,
347         uint            stop_on_cycle_no,
348         xfs_daddr_t     *new_blk)
349 {
350         xfs_daddr_t     i, j;
351         uint            cycle;
352         xfs_buf_t       *bp;
353         xfs_daddr_t     bufblks;
354         xfs_caddr_t     buf = NULL;
355         int             error = 0;
356
357         bufblks = 1 << ffs(nbblks);
358
359         while (!(bp = xlog_get_bp(log, bufblks))) {
360                 /* can't get enough memory to do everything in one big buffer */
361                 bufblks >>= 1;
362                 if (bufblks <= log->l_sectbb_log)
363                         return ENOMEM;
364         }
365
366         for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
367                 int     bcount;
368
369                 bcount = min(bufblks, (start_blk + nbblks - i));
370
371                 if ((error = xlog_bread(log, i, bcount, bp)))
372                         goto out;
373
374                 buf = xlog_align(log, i, bcount, bp);
375                 for (j = 0; j < bcount; j++) {
376                         cycle = xlog_get_cycle(buf);
377                         if (cycle == stop_on_cycle_no) {
378                                 *new_blk = i+j;
379                                 goto out;
380                         }
381
382                         buf += BBSIZE;
383                 }
384         }
385
386         *new_blk = -1;
387
388 out:
389         xlog_put_bp(bp);
390         return error;
391 }
392
393 /*
394  * Potentially backup over partial log record write.
395  *
396  * In the typical case, last_blk is the number of the block directly after
397  * a good log record.  Therefore, we subtract one to get the block number
398  * of the last block in the given buffer.  extra_bblks contains the number
399  * of blocks we would have read on a previous read.  This happens when the
400  * last log record is split over the end of the physical log.
401  *
402  * extra_bblks is the number of blocks potentially verified on a previous
403  * call to this routine.
404  */
405 STATIC int
406 xlog_find_verify_log_record(
407         xlog_t                  *log,
408         xfs_daddr_t             start_blk,
409         xfs_daddr_t             *last_blk,
410         int                     extra_bblks)
411 {
412         xfs_daddr_t             i;
413         xfs_buf_t               *bp;
414         xfs_caddr_t             offset = NULL;
415         xlog_rec_header_t       *head = NULL;
416         int                     error = 0;
417         int                     smallmem = 0;
418         int                     num_blks = *last_blk - start_blk;
419         int                     xhdrs;
420
421         ASSERT(start_blk != 0 || *last_blk != start_blk);
422
423         if (!(bp = xlog_get_bp(log, num_blks))) {
424                 if (!(bp = xlog_get_bp(log, 1)))
425                         return ENOMEM;
426                 smallmem = 1;
427         } else {
428                 if ((error = xlog_bread(log, start_blk, num_blks, bp)))
429                         goto out;
430                 offset = xlog_align(log, start_blk, num_blks, bp);
431                 offset += ((num_blks - 1) << BBSHIFT);
432         }
433
434         for (i = (*last_blk) - 1; i >= 0; i--) {
435                 if (i < start_blk) {
436                         /* valid log record not found */
437                         xlog_warn(
438                 "XFS: Log inconsistent (didn't find previous header)");
439                         ASSERT(0);
440                         error = XFS_ERROR(EIO);
441                         goto out;
442                 }
443
444                 if (smallmem) {
445                         if ((error = xlog_bread(log, i, 1, bp)))
446                                 goto out;
447                         offset = xlog_align(log, i, 1, bp);
448                 }
449
450                 head = (xlog_rec_header_t *)offset;
451
452                 if (XLOG_HEADER_MAGIC_NUM == be32_to_cpu(head->h_magicno))
453                         break;
454
455                 if (!smallmem)
456                         offset -= BBSIZE;
457         }
458
459         /*
460          * We hit the beginning of the physical log & still no header.  Return
461          * to caller.  If caller can handle a return of -1, then this routine
462          * will be called again for the end of the physical log.
463          */
464         if (i == -1) {
465                 error = -1;
466                 goto out;
467         }
468
469         /*
470          * We have the final block of the good log (the first block
471          * of the log record _before_ the head. So we check the uuid.
472          */
473         if ((error = xlog_header_check_mount(log->l_mp, head)))
474                 goto out;
475
476         /*
477          * We may have found a log record header before we expected one.
478          * last_blk will be the 1st block # with a given cycle #.  We may end
479          * up reading an entire log record.  In this case, we don't want to
480          * reset last_blk.  Only when last_blk points in the middle of a log
481          * record do we update last_blk.
482          */
483         if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
484                 uint    h_size = be32_to_cpu(head->h_size);
485
486                 xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
487                 if (h_size % XLOG_HEADER_CYCLE_SIZE)
488                         xhdrs++;
489         } else {
490                 xhdrs = 1;
491         }
492
493         if (*last_blk - i + extra_bblks !=
494             BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
495                 *last_blk = i;
496
497 out:
498         xlog_put_bp(bp);
499         return error;
500 }
501
502 /*
503  * Head is defined to be the point of the log where the next log write
504  * write could go.  This means that incomplete LR writes at the end are
505  * eliminated when calculating the head.  We aren't guaranteed that previous
506  * LR have complete transactions.  We only know that a cycle number of
507  * current cycle number -1 won't be present in the log if we start writing
508  * from our current block number.
509  *
510  * last_blk contains the block number of the first block with a given
511  * cycle number.
512  *
513  * Return: zero if normal, non-zero if error.
514  */
515 STATIC int
516 xlog_find_head(
517         xlog_t          *log,
518         xfs_daddr_t     *return_head_blk)
519 {
520         xfs_buf_t       *bp;
521         xfs_caddr_t     offset;
522         xfs_daddr_t     new_blk, first_blk, start_blk, last_blk, head_blk;
523         int             num_scan_bblks;
524         uint            first_half_cycle, last_half_cycle;
525         uint            stop_on_cycle;
526         int             error, log_bbnum = log->l_logBBsize;
527
528         /* Is the end of the log device zeroed? */
529         if ((error = xlog_find_zeroed(log, &first_blk)) == -1) {
530                 *return_head_blk = first_blk;
531
532                 /* Is the whole lot zeroed? */
533                 if (!first_blk) {
534                         /* Linux XFS shouldn't generate totally zeroed logs -
535                          * mkfs etc write a dummy unmount record to a fresh
536                          * log so we can store the uuid in there
537                          */
538                         xlog_warn("XFS: totally zeroed log");
539                 }
540
541                 return 0;
542         } else if (error) {
543                 xlog_warn("XFS: empty log check failed");
544                 return error;
545         }
546
547         first_blk = 0;                  /* get cycle # of 1st block */
548         bp = xlog_get_bp(log, 1);
549         if (!bp)
550                 return ENOMEM;
551         if ((error = xlog_bread(log, 0, 1, bp)))
552                 goto bp_err;
553         offset = xlog_align(log, 0, 1, bp);
554         first_half_cycle = xlog_get_cycle(offset);
555
556         last_blk = head_blk = log_bbnum - 1;    /* get cycle # of last block */
557         if ((error = xlog_bread(log, last_blk, 1, bp)))
558                 goto bp_err;
559         offset = xlog_align(log, last_blk, 1, bp);
560         last_half_cycle = xlog_get_cycle(offset);
561         ASSERT(last_half_cycle != 0);
562
563         /*
564          * If the 1st half cycle number is equal to the last half cycle number,
565          * then the entire log is stamped with the same cycle number.  In this
566          * case, head_blk can't be set to zero (which makes sense).  The below
567          * math doesn't work out properly with head_blk equal to zero.  Instead,
568          * we set it to log_bbnum which is an invalid block number, but this
569          * value makes the math correct.  If head_blk doesn't changed through
570          * all the tests below, *head_blk is set to zero at the very end rather
571          * than log_bbnum.  In a sense, log_bbnum and zero are the same block
572          * in a circular file.
573          */
574         if (first_half_cycle == last_half_cycle) {
575                 /*
576                  * In this case we believe that the entire log should have
577                  * cycle number last_half_cycle.  We need to scan backwards
578                  * from the end verifying that there are no holes still
579                  * containing last_half_cycle - 1.  If we find such a hole,
580                  * then the start of that hole will be the new head.  The
581                  * simple case looks like
582                  *        x | x ... | x - 1 | x
583                  * Another case that fits this picture would be
584                  *        x | x + 1 | x ... | x
585                  * In this case the head really is somewhere at the end of the
586                  * log, as one of the latest writes at the beginning was
587                  * incomplete.
588                  * One more case is
589                  *        x | x + 1 | x ... | x - 1 | x
590                  * This is really the combination of the above two cases, and
591                  * the head has to end up at the start of the x-1 hole at the
592                  * end of the log.
593                  *
594                  * In the 256k log case, we will read from the beginning to the
595                  * end of the log and search for cycle numbers equal to x-1.
596                  * We don't worry about the x+1 blocks that we encounter,
597                  * because we know that they cannot be the head since the log
598                  * started with x.
599                  */
600                 head_blk = log_bbnum;
601                 stop_on_cycle = last_half_cycle - 1;
602         } else {
603                 /*
604                  * In this case we want to find the first block with cycle
605                  * number matching last_half_cycle.  We expect the log to be
606                  * some variation on
607                  *        x + 1 ... | x ...
608                  * The first block with cycle number x (last_half_cycle) will
609                  * be where the new head belongs.  First we do a binary search
610                  * for the first occurrence of last_half_cycle.  The binary
611                  * search may not be totally accurate, so then we scan back
612                  * from there looking for occurrences of last_half_cycle before
613                  * us.  If that backwards scan wraps around the beginning of
614                  * the log, then we look for occurrences of last_half_cycle - 1
615                  * at the end of the log.  The cases we're looking for look
616                  * like
617                  *        x + 1 ... | x | x + 1 | x ...
618                  *                               ^ binary search stopped here
619                  * or
620                  *        x + 1 ... | x ... | x - 1 | x
621                  *        <---------> less than scan distance
622                  */
623                 stop_on_cycle = last_half_cycle;
624                 if ((error = xlog_find_cycle_start(log, bp, first_blk,
625                                                 &head_blk, last_half_cycle)))
626                         goto bp_err;
627         }
628
629         /*
630          * Now validate the answer.  Scan back some number of maximum possible
631          * blocks and make sure each one has the expected cycle number.  The
632          * maximum is determined by the total possible amount of buffering
633          * in the in-core log.  The following number can be made tighter if
634          * we actually look at the block size of the filesystem.
635          */
636         num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
637         if (head_blk >= num_scan_bblks) {
638                 /*
639                  * We are guaranteed that the entire check can be performed
640                  * in one buffer.
641                  */
642                 start_blk = head_blk - num_scan_bblks;
643                 if ((error = xlog_find_verify_cycle(log,
644                                                 start_blk, num_scan_bblks,
645                                                 stop_on_cycle, &new_blk)))
646                         goto bp_err;
647                 if (new_blk != -1)
648                         head_blk = new_blk;
649         } else {                /* need to read 2 parts of log */
650                 /*
651                  * We are going to scan backwards in the log in two parts.
652                  * First we scan the physical end of the log.  In this part
653                  * of the log, we are looking for blocks with cycle number
654                  * last_half_cycle - 1.
655                  * If we find one, then we know that the log starts there, as
656                  * we've found a hole that didn't get written in going around
657                  * the end of the physical log.  The simple case for this is
658                  *        x + 1 ... | x ... | x - 1 | x
659                  *        <---------> less than scan distance
660                  * If all of the blocks at the end of the log have cycle number
661                  * last_half_cycle, then we check the blocks at the start of
662                  * the log looking for occurrences of last_half_cycle.  If we
663                  * find one, then our current estimate for the location of the
664                  * first occurrence of last_half_cycle is wrong and we move
665                  * back to the hole we've found.  This case looks like
666                  *        x + 1 ... | x | x + 1 | x ...
667                  *                               ^ binary search stopped here
668                  * Another case we need to handle that only occurs in 256k
669                  * logs is
670                  *        x + 1 ... | x ... | x+1 | x ...
671                  *                   ^ binary search stops here
672                  * In a 256k log, the scan at the end of the log will see the
673                  * x + 1 blocks.  We need to skip past those since that is
674                  * certainly not the head of the log.  By searching for
675                  * last_half_cycle-1 we accomplish that.
676                  */
677                 start_blk = log_bbnum - num_scan_bblks + head_blk;
678                 ASSERT(head_blk <= INT_MAX &&
679                         (xfs_daddr_t) num_scan_bblks - head_blk >= 0);
680                 if ((error = xlog_find_verify_cycle(log, start_blk,
681                                         num_scan_bblks - (int)head_blk,
682                                         (stop_on_cycle - 1), &new_blk)))
683                         goto bp_err;
684                 if (new_blk != -1) {
685                         head_blk = new_blk;
686                         goto bad_blk;
687                 }
688
689                 /*
690                  * Scan beginning of log now.  The last part of the physical
691                  * log is good.  This scan needs to verify that it doesn't find
692                  * the last_half_cycle.
693                  */
694                 start_blk = 0;
695                 ASSERT(head_blk <= INT_MAX);
696                 if ((error = xlog_find_verify_cycle(log,
697                                         start_blk, (int)head_blk,
698                                         stop_on_cycle, &new_blk)))
699                         goto bp_err;
700                 if (new_blk != -1)
701                         head_blk = new_blk;
702         }
703
704  bad_blk:
705         /*
706          * Now we need to make sure head_blk is not pointing to a block in
707          * the middle of a log record.
708          */
709         num_scan_bblks = XLOG_REC_SHIFT(log);
710         if (head_blk >= num_scan_bblks) {
711                 start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
712
713                 /* start ptr at last block ptr before head_blk */
714                 if ((error = xlog_find_verify_log_record(log, start_blk,
715                                                         &head_blk, 0)) == -1) {
716                         error = XFS_ERROR(EIO);
717                         goto bp_err;
718                 } else if (error)
719                         goto bp_err;
720         } else {
721                 start_blk = 0;
722                 ASSERT(head_blk <= INT_MAX);
723                 if ((error = xlog_find_verify_log_record(log, start_blk,
724                                                         &head_blk, 0)) == -1) {
725                         /* We hit the beginning of the log during our search */
726                         start_blk = log_bbnum - num_scan_bblks + head_blk;
727                         new_blk = log_bbnum;
728                         ASSERT(start_blk <= INT_MAX &&
729                                 (xfs_daddr_t) log_bbnum-start_blk >= 0);
730                         ASSERT(head_blk <= INT_MAX);
731                         if ((error = xlog_find_verify_log_record(log,
732                                                         start_blk, &new_blk,
733                                                         (int)head_blk)) == -1) {
734                                 error = XFS_ERROR(EIO);
735                                 goto bp_err;
736                         } else if (error)
737                                 goto bp_err;
738                         if (new_blk != log_bbnum)
739                                 head_blk = new_blk;
740                 } else if (error)
741                         goto bp_err;
742         }
743
744         xlog_put_bp(bp);
745         if (head_blk == log_bbnum)
746                 *return_head_blk = 0;
747         else
748                 *return_head_blk = head_blk;
749         /*
750          * When returning here, we have a good block number.  Bad block
751          * means that during a previous crash, we didn't have a clean break
752          * from cycle number N to cycle number N-1.  In this case, we need
753          * to find the first block with cycle number N-1.
754          */
755         return 0;
756
757  bp_err:
758         xlog_put_bp(bp);
759
760         if (error)
761             xlog_warn("XFS: failed to find log head");
762         return error;
763 }
764
765 /*
766  * Find the sync block number or the tail of the log.
767  *
768  * This will be the block number of the last record to have its
769  * associated buffers synced to disk.  Every log record header has
770  * a sync lsn embedded in it.  LSNs hold block numbers, so it is easy
771  * to get a sync block number.  The only concern is to figure out which
772  * log record header to believe.
773  *
774  * The following algorithm uses the log record header with the largest
775  * lsn.  The entire log record does not need to be valid.  We only care
776  * that the header is valid.
777  *
778  * We could speed up search by using current head_blk buffer, but it is not
779  * available.
780  */
781 int
782 xlog_find_tail(
783         xlog_t                  *log,
784         xfs_daddr_t             *head_blk,
785         xfs_daddr_t             *tail_blk)
786 {
787         xlog_rec_header_t       *rhead;
788         xlog_op_header_t        *op_head;
789         xfs_caddr_t             offset = NULL;
790         xfs_buf_t               *bp;
791         int                     error, i, found;
792         xfs_daddr_t             umount_data_blk;
793         xfs_daddr_t             after_umount_blk;
794         xfs_lsn_t               tail_lsn;
795         int                     hblks;
796
797         found = 0;
798
799         /*
800          * Find previous log record
801          */
802         if ((error = xlog_find_head(log, head_blk)))
803                 return error;
804
805         bp = xlog_get_bp(log, 1);
806         if (!bp)
807                 return ENOMEM;
808         if (*head_blk == 0) {                           /* special case */
809                 if ((error = xlog_bread(log, 0, 1, bp)))
810                         goto bread_err;
811                 offset = xlog_align(log, 0, 1, bp);
812                 if (xlog_get_cycle(offset) == 0) {
813                         *tail_blk = 0;
814                         /* leave all other log inited values alone */
815                         goto exit;
816                 }
817         }
818
819         /*
820          * Search backwards looking for log record header block
821          */
822         ASSERT(*head_blk < INT_MAX);
823         for (i = (int)(*head_blk) - 1; i >= 0; i--) {
824                 if ((error = xlog_bread(log, i, 1, bp)))
825                         goto bread_err;
826                 offset = xlog_align(log, i, 1, bp);
827                 if (XLOG_HEADER_MAGIC_NUM == be32_to_cpu(*(__be32 *)offset)) {
828                         found = 1;
829                         break;
830                 }
831         }
832         /*
833          * If we haven't found the log record header block, start looking
834          * again from the end of the physical log.  XXXmiken: There should be
835          * a check here to make sure we didn't search more than N blocks in
836          * the previous code.
837          */
838         if (!found) {
839                 for (i = log->l_logBBsize - 1; i >= (int)(*head_blk); i--) {
840                         if ((error = xlog_bread(log, i, 1, bp)))
841                                 goto bread_err;
842                         offset = xlog_align(log, i, 1, bp);
843                         if (XLOG_HEADER_MAGIC_NUM ==
844                             be32_to_cpu(*(__be32 *)offset)) {
845                                 found = 2;
846                                 break;
847                         }
848                 }
849         }
850         if (!found) {
851                 xlog_warn("XFS: xlog_find_tail: couldn't find sync record");
852                 ASSERT(0);
853                 return XFS_ERROR(EIO);
854         }
855
856         /* find blk_no of tail of log */
857         rhead = (xlog_rec_header_t *)offset;
858         *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
859
860         /*
861          * Reset log values according to the state of the log when we
862          * crashed.  In the case where head_blk == 0, we bump curr_cycle
863          * one because the next write starts a new cycle rather than
864          * continuing the cycle of the last good log record.  At this
865          * point we have guaranteed that all partial log records have been
866          * accounted for.  Therefore, we know that the last good log record
867          * written was complete and ended exactly on the end boundary
868          * of the physical log.
869          */
870         log->l_prev_block = i;
871         log->l_curr_block = (int)*head_blk;
872         log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
873         if (found == 2)
874                 log->l_curr_cycle++;
875         log->l_tail_lsn = be64_to_cpu(rhead->h_tail_lsn);
876         log->l_last_sync_lsn = be64_to_cpu(rhead->h_lsn);
877         log->l_grant_reserve_cycle = log->l_curr_cycle;
878         log->l_grant_reserve_bytes = BBTOB(log->l_curr_block);
879         log->l_grant_write_cycle = log->l_curr_cycle;
880         log->l_grant_write_bytes = BBTOB(log->l_curr_block);
881
882         /*
883          * Look for unmount record.  If we find it, then we know there
884          * was a clean unmount.  Since 'i' could be the last block in
885          * the physical log, we convert to a log block before comparing
886          * to the head_blk.
887          *
888          * Save the current tail lsn to use to pass to
889          * xlog_clear_stale_blocks() below.  We won't want to clear the
890          * unmount record if there is one, so we pass the lsn of the
891          * unmount record rather than the block after it.
892          */
893         if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
894                 int     h_size = be32_to_cpu(rhead->h_size);
895                 int     h_version = be32_to_cpu(rhead->h_version);
896
897                 if ((h_version & XLOG_VERSION_2) &&
898                     (h_size > XLOG_HEADER_CYCLE_SIZE)) {
899                         hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
900                         if (h_size % XLOG_HEADER_CYCLE_SIZE)
901                                 hblks++;
902                 } else {
903                         hblks = 1;
904                 }
905         } else {
906                 hblks = 1;
907         }
908         after_umount_blk = (i + hblks + (int)
909                 BTOBB(be32_to_cpu(rhead->h_len))) % log->l_logBBsize;
910         tail_lsn = log->l_tail_lsn;
911         if (*head_blk == after_umount_blk &&
912             be32_to_cpu(rhead->h_num_logops) == 1) {
913                 umount_data_blk = (i + hblks) % log->l_logBBsize;
914                 if ((error = xlog_bread(log, umount_data_blk, 1, bp))) {
915                         goto bread_err;
916                 }
917                 offset = xlog_align(log, umount_data_blk, 1, bp);
918                 op_head = (xlog_op_header_t *)offset;
919                 if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
920                         /*
921                          * Set tail and last sync so that newly written
922                          * log records will point recovery to after the
923                          * current unmount record.
924                          */
925                         log->l_tail_lsn =
926                                 xlog_assign_lsn(log->l_curr_cycle,
927                                                 after_umount_blk);
928                         log->l_last_sync_lsn =
929                                 xlog_assign_lsn(log->l_curr_cycle,
930                                                 after_umount_blk);
931                         *tail_blk = after_umount_blk;
932
933                         /*
934                          * Note that the unmount was clean. If the unmount
935                          * was not clean, we need to know this to rebuild the
936                          * superblock counters from the perag headers if we
937                          * have a filesystem using non-persistent counters.
938                          */
939                         log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN;
940                 }
941         }
942
943         /*
944          * Make sure that there are no blocks in front of the head
945          * with the same cycle number as the head.  This can happen
946          * because we allow multiple outstanding log writes concurrently,
947          * and the later writes might make it out before earlier ones.
948          *
949          * We use the lsn from before modifying it so that we'll never
950          * overwrite the unmount record after a clean unmount.
951          *
952          * Do this only if we are going to recover the filesystem
953          *
954          * NOTE: This used to say "if (!readonly)"
955          * However on Linux, we can & do recover a read-only filesystem.
956          * We only skip recovery if NORECOVERY is specified on mount,
957          * in which case we would not be here.
958          *
959          * But... if the -device- itself is readonly, just skip this.
960          * We can't recover this device anyway, so it won't matter.
961          */
962         if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) {
963                 error = xlog_clear_stale_blocks(log, tail_lsn);
964         }
965
966 bread_err:
967 exit:
968         xlog_put_bp(bp);
969
970         if (error)
971                 xlog_warn("XFS: failed to locate log tail");
972         return error;
973 }
974
975 /*
976  * Is the log zeroed at all?
977  *
978  * The last binary search should be changed to perform an X block read
979  * once X becomes small enough.  You can then search linearly through
980  * the X blocks.  This will cut down on the number of reads we need to do.
981  *
982  * If the log is partially zeroed, this routine will pass back the blkno
983  * of the first block with cycle number 0.  It won't have a complete LR
984  * preceding it.
985  *
986  * Return:
987  *      0  => the log is completely written to
988  *      -1 => use *blk_no as the first block of the log
989  *      >0 => error has occurred
990  */
991 STATIC int
992 xlog_find_zeroed(
993         xlog_t          *log,
994         xfs_daddr_t     *blk_no)
995 {
996         xfs_buf_t       *bp;
997         xfs_caddr_t     offset;
998         uint            first_cycle, last_cycle;
999         xfs_daddr_t     new_blk, last_blk, start_blk;
1000         xfs_daddr_t     num_scan_bblks;
1001         int             error, log_bbnum = log->l_logBBsize;
1002
1003         *blk_no = 0;
1004
1005         /* check totally zeroed log */
1006         bp = xlog_get_bp(log, 1);
1007         if (!bp)
1008                 return ENOMEM;
1009         if ((error = xlog_bread(log, 0, 1, bp)))
1010                 goto bp_err;
1011         offset = xlog_align(log, 0, 1, bp);
1012         first_cycle = xlog_get_cycle(offset);
1013         if (first_cycle == 0) {         /* completely zeroed log */
1014                 *blk_no = 0;
1015                 xlog_put_bp(bp);
1016                 return -1;
1017         }
1018
1019         /* check partially zeroed log */
1020         if ((error = xlog_bread(log, log_bbnum-1, 1, bp)))
1021                 goto bp_err;
1022         offset = xlog_align(log, log_bbnum-1, 1, bp);
1023         last_cycle = xlog_get_cycle(offset);
1024         if (last_cycle != 0) {          /* log completely written to */
1025                 xlog_put_bp(bp);
1026                 return 0;
1027         } else if (first_cycle != 1) {
1028                 /*
1029                  * If the cycle of the last block is zero, the cycle of
1030                  * the first block must be 1. If it's not, maybe we're
1031                  * not looking at a log... Bail out.
1032                  */
1033                 xlog_warn("XFS: Log inconsistent or not a log (last==0, first!=1)");
1034                 return XFS_ERROR(EINVAL);
1035         }
1036
1037         /* we have a partially zeroed log */
1038         last_blk = log_bbnum-1;
1039         if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0)))
1040                 goto bp_err;
1041
1042         /*
1043          * Validate the answer.  Because there is no way to guarantee that
1044          * the entire log is made up of log records which are the same size,
1045          * we scan over the defined maximum blocks.  At this point, the maximum
1046          * is not chosen to mean anything special.   XXXmiken
1047          */
1048         num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1049         ASSERT(num_scan_bblks <= INT_MAX);
1050
1051         if (last_blk < num_scan_bblks)
1052                 num_scan_bblks = last_blk;
1053         start_blk = last_blk - num_scan_bblks;
1054
1055         /*
1056          * We search for any instances of cycle number 0 that occur before
1057          * our current estimate of the head.  What we're trying to detect is
1058          *        1 ... | 0 | 1 | 0...
1059          *                       ^ binary search ends here
1060          */
1061         if ((error = xlog_find_verify_cycle(log, start_blk,
1062                                          (int)num_scan_bblks, 0, &new_blk)))
1063                 goto bp_err;
1064         if (new_blk != -1)
1065                 last_blk = new_blk;
1066
1067         /*
1068          * Potentially backup over partial log record write.  We don't need
1069          * to search the end of the log because we know it is zero.
1070          */
1071         if ((error = xlog_find_verify_log_record(log, start_blk,
1072                                 &last_blk, 0)) == -1) {
1073             error = XFS_ERROR(EIO);
1074             goto bp_err;
1075         } else if (error)
1076             goto bp_err;
1077
1078         *blk_no = last_blk;
1079 bp_err:
1080         xlog_put_bp(bp);
1081         if (error)
1082                 return error;
1083         return -1;
1084 }
1085
1086 /*
1087  * These are simple subroutines used by xlog_clear_stale_blocks() below
1088  * to initialize a buffer full of empty log record headers and write
1089  * them into the log.
1090  */
1091 STATIC void
1092 xlog_add_record(
1093         xlog_t                  *log,
1094         xfs_caddr_t             buf,
1095         int                     cycle,
1096         int                     block,
1097         int                     tail_cycle,
1098         int                     tail_block)
1099 {
1100         xlog_rec_header_t       *recp = (xlog_rec_header_t *)buf;
1101
1102         memset(buf, 0, BBSIZE);
1103         recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1104         recp->h_cycle = cpu_to_be32(cycle);
1105         recp->h_version = cpu_to_be32(
1106                         xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1107         recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1108         recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1109         recp->h_fmt = cpu_to_be32(XLOG_FMT);
1110         memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1111 }
1112
1113 STATIC int
1114 xlog_write_log_records(
1115         xlog_t          *log,
1116         int             cycle,
1117         int             start_block,
1118         int             blocks,
1119         int             tail_cycle,
1120         int             tail_block)
1121 {
1122         xfs_caddr_t     offset;
1123         xfs_buf_t       *bp;
1124         int             balign, ealign;
1125         int             sectbb = XLOG_SECTOR_ROUNDUP_BBCOUNT(log, 1);
1126         int             end_block = start_block + blocks;
1127         int             bufblks;
1128         int             error = 0;
1129         int             i, j = 0;
1130
1131         bufblks = 1 << ffs(blocks);
1132         while (!(bp = xlog_get_bp(log, bufblks))) {
1133                 bufblks >>= 1;
1134                 if (bufblks <= log->l_sectbb_log)
1135                         return ENOMEM;
1136         }
1137
1138         /* We may need to do a read at the start to fill in part of
1139          * the buffer in the starting sector not covered by the first
1140          * write below.
1141          */
1142         balign = XLOG_SECTOR_ROUNDDOWN_BLKNO(log, start_block);
1143         if (balign != start_block) {
1144                 if ((error = xlog_bread(log, start_block, 1, bp))) {
1145                         xlog_put_bp(bp);
1146                         return error;
1147                 }
1148                 j = start_block - balign;
1149         }
1150
1151         for (i = start_block; i < end_block; i += bufblks) {
1152                 int             bcount, endcount;
1153
1154                 bcount = min(bufblks, end_block - start_block);
1155                 endcount = bcount - j;
1156
1157                 /* We may need to do a read at the end to fill in part of
1158                  * the buffer in the final sector not covered by the write.
1159                  * If this is the same sector as the above read, skip it.
1160                  */
1161                 ealign = XLOG_SECTOR_ROUNDDOWN_BLKNO(log, end_block);
1162                 if (j == 0 && (start_block + endcount > ealign)) {
1163                         offset = XFS_BUF_PTR(bp);
1164                         balign = BBTOB(ealign - start_block);
1165                         error = XFS_BUF_SET_PTR(bp, offset + balign,
1166                                                 BBTOB(sectbb));
1167                         if (!error)
1168                                 error = xlog_bread(log, ealign, sectbb, bp);
1169                         if (!error)
1170                                 error = XFS_BUF_SET_PTR(bp, offset, bufblks);
1171                         if (error)
1172                                 break;
1173                 }
1174
1175                 offset = xlog_align(log, start_block, endcount, bp);
1176                 for (; j < endcount; j++) {
1177                         xlog_add_record(log, offset, cycle, i+j,
1178                                         tail_cycle, tail_block);
1179                         offset += BBSIZE;
1180                 }
1181                 error = xlog_bwrite(log, start_block, endcount, bp);
1182                 if (error)
1183                         break;
1184                 start_block += endcount;
1185                 j = 0;
1186         }
1187         xlog_put_bp(bp);
1188         return error;
1189 }
1190
1191 /*
1192  * This routine is called to blow away any incomplete log writes out
1193  * in front of the log head.  We do this so that we won't become confused
1194  * if we come up, write only a little bit more, and then crash again.
1195  * If we leave the partial log records out there, this situation could
1196  * cause us to think those partial writes are valid blocks since they
1197  * have the current cycle number.  We get rid of them by overwriting them
1198  * with empty log records with the old cycle number rather than the
1199  * current one.
1200  *
1201  * The tail lsn is passed in rather than taken from
1202  * the log so that we will not write over the unmount record after a
1203  * clean unmount in a 512 block log.  Doing so would leave the log without
1204  * any valid log records in it until a new one was written.  If we crashed
1205  * during that time we would not be able to recover.
1206  */
1207 STATIC int
1208 xlog_clear_stale_blocks(
1209         xlog_t          *log,
1210         xfs_lsn_t       tail_lsn)
1211 {
1212         int             tail_cycle, head_cycle;
1213         int             tail_block, head_block;
1214         int             tail_distance, max_distance;
1215         int             distance;
1216         int             error;
1217
1218         tail_cycle = CYCLE_LSN(tail_lsn);
1219         tail_block = BLOCK_LSN(tail_lsn);
1220         head_cycle = log->l_curr_cycle;
1221         head_block = log->l_curr_block;
1222
1223         /*
1224          * Figure out the distance between the new head of the log
1225          * and the tail.  We want to write over any blocks beyond the
1226          * head that we may have written just before the crash, but
1227          * we don't want to overwrite the tail of the log.
1228          */
1229         if (head_cycle == tail_cycle) {
1230                 /*
1231                  * The tail is behind the head in the physical log,
1232                  * so the distance from the head to the tail is the
1233                  * distance from the head to the end of the log plus
1234                  * the distance from the beginning of the log to the
1235                  * tail.
1236                  */
1237                 if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) {
1238                         XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)",
1239                                          XFS_ERRLEVEL_LOW, log->l_mp);
1240                         return XFS_ERROR(EFSCORRUPTED);
1241                 }
1242                 tail_distance = tail_block + (log->l_logBBsize - head_block);
1243         } else {
1244                 /*
1245                  * The head is behind the tail in the physical log,
1246                  * so the distance from the head to the tail is just
1247                  * the tail block minus the head block.
1248                  */
1249                 if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){
1250                         XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)",
1251                                          XFS_ERRLEVEL_LOW, log->l_mp);
1252                         return XFS_ERROR(EFSCORRUPTED);
1253                 }
1254                 tail_distance = tail_block - head_block;
1255         }
1256
1257         /*
1258          * If the head is right up against the tail, we can't clear
1259          * anything.
1260          */
1261         if (tail_distance <= 0) {
1262                 ASSERT(tail_distance == 0);
1263                 return 0;
1264         }
1265
1266         max_distance = XLOG_TOTAL_REC_SHIFT(log);
1267         /*
1268          * Take the smaller of the maximum amount of outstanding I/O
1269          * we could have and the distance to the tail to clear out.
1270          * We take the smaller so that we don't overwrite the tail and
1271          * we don't waste all day writing from the head to the tail
1272          * for no reason.
1273          */
1274         max_distance = MIN(max_distance, tail_distance);
1275
1276         if ((head_block + max_distance) <= log->l_logBBsize) {
1277                 /*
1278                  * We can stomp all the blocks we need to without
1279                  * wrapping around the end of the log.  Just do it
1280                  * in a single write.  Use the cycle number of the
1281                  * current cycle minus one so that the log will look like:
1282                  *     n ... | n - 1 ...
1283                  */
1284                 error = xlog_write_log_records(log, (head_cycle - 1),
1285                                 head_block, max_distance, tail_cycle,
1286                                 tail_block);
1287                 if (error)
1288                         return error;
1289         } else {
1290                 /*
1291                  * We need to wrap around the end of the physical log in
1292                  * order to clear all the blocks.  Do it in two separate
1293                  * I/Os.  The first write should be from the head to the
1294                  * end of the physical log, and it should use the current
1295                  * cycle number minus one just like above.
1296                  */
1297                 distance = log->l_logBBsize - head_block;
1298                 error = xlog_write_log_records(log, (head_cycle - 1),
1299                                 head_block, distance, tail_cycle,
1300                                 tail_block);
1301
1302                 if (error)
1303                         return error;
1304
1305                 /*
1306                  * Now write the blocks at the start of the physical log.
1307                  * This writes the remainder of the blocks we want to clear.
1308                  * It uses the current cycle number since we're now on the
1309                  * same cycle as the head so that we get:
1310                  *    n ... n ... | n - 1 ...
1311                  *    ^^^^^ blocks we're writing
1312                  */
1313                 distance = max_distance - (log->l_logBBsize - head_block);
1314                 error = xlog_write_log_records(log, head_cycle, 0, distance,
1315                                 tail_cycle, tail_block);
1316                 if (error)
1317                         return error;
1318         }
1319
1320         return 0;
1321 }
1322
1323 /******************************************************************************
1324  *
1325  *              Log recover routines
1326  *
1327  ******************************************************************************
1328  */
1329
1330 STATIC xlog_recover_t *
1331 xlog_recover_find_tid(
1332         xlog_recover_t          *q,
1333         xlog_tid_t              tid)
1334 {
1335         xlog_recover_t          *p = q;
1336
1337         while (p != NULL) {
1338                 if (p->r_log_tid == tid)
1339                     break;
1340                 p = p->r_next;
1341         }
1342         return p;
1343 }
1344
1345 STATIC void
1346 xlog_recover_put_hashq(
1347         xlog_recover_t          **q,
1348         xlog_recover_t          *trans)
1349 {
1350         trans->r_next = *q;
1351         *q = trans;
1352 }
1353
1354 STATIC void
1355 xlog_recover_add_item(
1356         xlog_recover_item_t     **itemq)
1357 {
1358         xlog_recover_item_t     *item;
1359
1360         item = kmem_zalloc(sizeof(xlog_recover_item_t), KM_SLEEP);
1361         xlog_recover_insert_item_backq(itemq, item);
1362 }
1363
1364 STATIC int
1365 xlog_recover_add_to_cont_trans(
1366         xlog_recover_t          *trans,
1367         xfs_caddr_t             dp,
1368         int                     len)
1369 {
1370         xlog_recover_item_t     *item;
1371         xfs_caddr_t             ptr, old_ptr;
1372         int                     old_len;
1373
1374         item = trans->r_itemq;
1375         if (item == NULL) {
1376                 /* finish copying rest of trans header */
1377                 xlog_recover_add_item(&trans->r_itemq);
1378                 ptr = (xfs_caddr_t) &trans->r_theader +
1379                                 sizeof(xfs_trans_header_t) - len;
1380                 memcpy(ptr, dp, len); /* d, s, l */
1381                 return 0;
1382         }
1383         item = item->ri_prev;
1384
1385         old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
1386         old_len = item->ri_buf[item->ri_cnt-1].i_len;
1387
1388         ptr = kmem_realloc(old_ptr, len+old_len, old_len, 0u);
1389         memcpy(&ptr[old_len], dp, len); /* d, s, l */
1390         item->ri_buf[item->ri_cnt-1].i_len += len;
1391         item->ri_buf[item->ri_cnt-1].i_addr = ptr;
1392         return 0;
1393 }
1394
1395 /*
1396  * The next region to add is the start of a new region.  It could be
1397  * a whole region or it could be the first part of a new region.  Because
1398  * of this, the assumption here is that the type and size fields of all
1399  * format structures fit into the first 32 bits of the structure.
1400  *
1401  * This works because all regions must be 32 bit aligned.  Therefore, we
1402  * either have both fields or we have neither field.  In the case we have
1403  * neither field, the data part of the region is zero length.  We only have
1404  * a log_op_header and can throw away the header since a new one will appear
1405  * later.  If we have at least 4 bytes, then we can determine how many regions
1406  * will appear in the current log item.
1407  */
1408 STATIC int
1409 xlog_recover_add_to_trans(
1410         xlog_recover_t          *trans,
1411         xfs_caddr_t             dp,
1412         int                     len)
1413 {
1414         xfs_inode_log_format_t  *in_f;                  /* any will do */
1415         xlog_recover_item_t     *item;
1416         xfs_caddr_t             ptr;
1417
1418         if (!len)
1419                 return 0;
1420         item = trans->r_itemq;
1421         if (item == NULL) {
1422                 ASSERT(*(uint *)dp == XFS_TRANS_HEADER_MAGIC);
1423                 if (len == sizeof(xfs_trans_header_t))
1424                         xlog_recover_add_item(&trans->r_itemq);
1425                 memcpy(&trans->r_theader, dp, len); /* d, s, l */
1426                 return 0;
1427         }
1428
1429         ptr = kmem_alloc(len, KM_SLEEP);
1430         memcpy(ptr, dp, len);
1431         in_f = (xfs_inode_log_format_t *)ptr;
1432
1433         if (item->ri_prev->ri_total != 0 &&
1434              item->ri_prev->ri_total == item->ri_prev->ri_cnt) {
1435                 xlog_recover_add_item(&trans->r_itemq);
1436         }
1437         item = trans->r_itemq;
1438         item = item->ri_prev;
1439
1440         if (item->ri_total == 0) {              /* first region to be added */
1441                 item->ri_total  = in_f->ilf_size;
1442                 ASSERT(item->ri_total <= XLOG_MAX_REGIONS_IN_ITEM);
1443                 item->ri_buf = kmem_zalloc((item->ri_total *
1444                                             sizeof(xfs_log_iovec_t)), KM_SLEEP);
1445         }
1446         ASSERT(item->ri_total > item->ri_cnt);
1447         /* Description region is ri_buf[0] */
1448         item->ri_buf[item->ri_cnt].i_addr = ptr;
1449         item->ri_buf[item->ri_cnt].i_len  = len;
1450         item->ri_cnt++;
1451         return 0;
1452 }
1453
1454 STATIC void
1455 xlog_recover_new_tid(
1456         xlog_recover_t          **q,
1457         xlog_tid_t              tid,
1458         xfs_lsn_t               lsn)
1459 {
1460         xlog_recover_t          *trans;
1461
1462         trans = kmem_zalloc(sizeof(xlog_recover_t), KM_SLEEP);
1463         trans->r_log_tid   = tid;
1464         trans->r_lsn       = lsn;
1465         xlog_recover_put_hashq(q, trans);
1466 }
1467
1468 STATIC int
1469 xlog_recover_unlink_tid(
1470         xlog_recover_t          **q,
1471         xlog_recover_t          *trans)
1472 {
1473         xlog_recover_t          *tp;
1474         int                     found = 0;
1475
1476         ASSERT(trans != NULL);
1477         if (trans == *q) {
1478                 *q = (*q)->r_next;
1479         } else {
1480                 tp = *q;
1481                 while (tp) {
1482                         if (tp->r_next == trans) {
1483                                 found = 1;
1484                                 break;
1485                         }
1486                         tp = tp->r_next;
1487                 }
1488                 if (!found) {
1489                         xlog_warn(
1490                              "XFS: xlog_recover_unlink_tid: trans not found");
1491                         ASSERT(0);
1492                         return XFS_ERROR(EIO);
1493                 }
1494                 tp->r_next = tp->r_next->r_next;
1495         }
1496         return 0;
1497 }
1498
1499 STATIC void
1500 xlog_recover_insert_item_backq(
1501         xlog_recover_item_t     **q,
1502         xlog_recover_item_t     *item)
1503 {
1504         if (*q == NULL) {
1505                 item->ri_prev = item->ri_next = item;
1506                 *q = item;
1507         } else {
1508                 item->ri_next           = *q;
1509                 item->ri_prev           = (*q)->ri_prev;
1510                 (*q)->ri_prev           = item;
1511                 item->ri_prev->ri_next  = item;
1512         }
1513 }
1514
1515 STATIC void
1516 xlog_recover_insert_item_frontq(
1517         xlog_recover_item_t     **q,
1518         xlog_recover_item_t     *item)
1519 {
1520         xlog_recover_insert_item_backq(q, item);
1521         *q = item;
1522 }
1523
1524 STATIC int
1525 xlog_recover_reorder_trans(
1526         xlog_recover_t          *trans)
1527 {
1528         xlog_recover_item_t     *first_item, *itemq, *itemq_next;
1529         xfs_buf_log_format_t    *buf_f;
1530         ushort                  flags = 0;
1531
1532         first_item = itemq = trans->r_itemq;
1533         trans->r_itemq = NULL;
1534         do {
1535                 itemq_next = itemq->ri_next;
1536                 buf_f = (xfs_buf_log_format_t *)itemq->ri_buf[0].i_addr;
1537
1538                 switch (ITEM_TYPE(itemq)) {
1539                 case XFS_LI_BUF:
1540                         flags = buf_f->blf_flags;
1541                         if (!(flags & XFS_BLI_CANCEL)) {
1542                                 xlog_recover_insert_item_frontq(&trans->r_itemq,
1543                                                                 itemq);
1544                                 break;
1545                         }
1546                 case XFS_LI_INODE:
1547                 case XFS_LI_DQUOT:
1548                 case XFS_LI_QUOTAOFF:
1549                 case XFS_LI_EFD:
1550                 case XFS_LI_EFI:
1551                         xlog_recover_insert_item_backq(&trans->r_itemq, itemq);
1552                         break;
1553                 default:
1554                         xlog_warn(
1555         "XFS: xlog_recover_reorder_trans: unrecognized type of log operation");
1556                         ASSERT(0);
1557                         return XFS_ERROR(EIO);
1558                 }
1559                 itemq = itemq_next;
1560         } while (first_item != itemq);
1561         return 0;
1562 }
1563
1564 /*
1565  * Build up the table of buf cancel records so that we don't replay
1566  * cancelled data in the second pass.  For buffer records that are
1567  * not cancel records, there is nothing to do here so we just return.
1568  *
1569  * If we get a cancel record which is already in the table, this indicates
1570  * that the buffer was cancelled multiple times.  In order to ensure
1571  * that during pass 2 we keep the record in the table until we reach its
1572  * last occurrence in the log, we keep a reference count in the cancel
1573  * record in the table to tell us how many times we expect to see this
1574  * record during the second pass.
1575  */
1576 STATIC void
1577 xlog_recover_do_buffer_pass1(
1578         xlog_t                  *log,
1579         xfs_buf_log_format_t    *buf_f)
1580 {
1581         xfs_buf_cancel_t        *bcp;
1582         xfs_buf_cancel_t        *nextp;
1583         xfs_buf_cancel_t        *prevp;
1584         xfs_buf_cancel_t        **bucket;
1585         xfs_daddr_t             blkno = 0;
1586         uint                    len = 0;
1587         ushort                  flags = 0;
1588
1589         switch (buf_f->blf_type) {
1590         case XFS_LI_BUF:
1591                 blkno = buf_f->blf_blkno;
1592                 len = buf_f->blf_len;
1593                 flags = buf_f->blf_flags;
1594                 break;
1595         }
1596
1597         /*
1598          * If this isn't a cancel buffer item, then just return.
1599          */
1600         if (!(flags & XFS_BLI_CANCEL))
1601                 return;
1602
1603         /*
1604          * Insert an xfs_buf_cancel record into the hash table of
1605          * them.  If there is already an identical record, bump
1606          * its reference count.
1607          */
1608         bucket = &log->l_buf_cancel_table[(__uint64_t)blkno %
1609                                           XLOG_BC_TABLE_SIZE];
1610         /*
1611          * If the hash bucket is empty then just insert a new record into
1612          * the bucket.
1613          */
1614         if (*bucket == NULL) {
1615                 bcp = (xfs_buf_cancel_t *)kmem_alloc(sizeof(xfs_buf_cancel_t),
1616                                                      KM_SLEEP);
1617                 bcp->bc_blkno = blkno;
1618                 bcp->bc_len = len;
1619                 bcp->bc_refcount = 1;
1620                 bcp->bc_next = NULL;
1621                 *bucket = bcp;
1622                 return;
1623         }
1624
1625         /*
1626          * The hash bucket is not empty, so search for duplicates of our
1627          * record.  If we find one them just bump its refcount.  If not
1628          * then add us at the end of the list.
1629          */
1630         prevp = NULL;
1631         nextp = *bucket;
1632         while (nextp != NULL) {
1633                 if (nextp->bc_blkno == blkno && nextp->bc_len == len) {
1634                         nextp->bc_refcount++;
1635                         return;
1636                 }
1637                 prevp = nextp;
1638                 nextp = nextp->bc_next;
1639         }
1640         ASSERT(prevp != NULL);
1641         bcp = (xfs_buf_cancel_t *)kmem_alloc(sizeof(xfs_buf_cancel_t),
1642                                              KM_SLEEP);
1643         bcp->bc_blkno = blkno;
1644         bcp->bc_len = len;
1645         bcp->bc_refcount = 1;
1646         bcp->bc_next = NULL;
1647         prevp->bc_next = bcp;
1648 }
1649
1650 /*
1651  * Check to see whether the buffer being recovered has a corresponding
1652  * entry in the buffer cancel record table.  If it does then return 1
1653  * so that it will be cancelled, otherwise return 0.  If the buffer is
1654  * actually a buffer cancel item (XFS_BLI_CANCEL is set), then decrement
1655  * the refcount on the entry in the table and remove it from the table
1656  * if this is the last reference.
1657  *
1658  * We remove the cancel record from the table when we encounter its
1659  * last occurrence in the log so that if the same buffer is re-used
1660  * again after its last cancellation we actually replay the changes
1661  * made at that point.
1662  */
1663 STATIC int
1664 xlog_check_buffer_cancelled(
1665         xlog_t                  *log,
1666         xfs_daddr_t             blkno,
1667         uint                    len,
1668         ushort                  flags)
1669 {
1670         xfs_buf_cancel_t        *bcp;
1671         xfs_buf_cancel_t        *prevp;
1672         xfs_buf_cancel_t        **bucket;
1673
1674         if (log->l_buf_cancel_table == NULL) {
1675                 /*
1676                  * There is nothing in the table built in pass one,
1677                  * so this buffer must not be cancelled.
1678                  */
1679                 ASSERT(!(flags & XFS_BLI_CANCEL));
1680                 return 0;
1681         }
1682
1683         bucket = &log->l_buf_cancel_table[(__uint64_t)blkno %
1684                                           XLOG_BC_TABLE_SIZE];
1685         bcp = *bucket;
1686         if (bcp == NULL) {
1687                 /*
1688                  * There is no corresponding entry in the table built
1689                  * in pass one, so this buffer has not been cancelled.
1690                  */
1691                 ASSERT(!(flags & XFS_BLI_CANCEL));
1692                 return 0;
1693         }
1694
1695         /*
1696          * Search for an entry in the buffer cancel table that
1697          * matches our buffer.
1698          */
1699         prevp = NULL;
1700         while (bcp != NULL) {
1701                 if (bcp->bc_blkno == blkno && bcp->bc_len == len) {
1702                         /*
1703                          * We've go a match, so return 1 so that the
1704                          * recovery of this buffer is cancelled.
1705                          * If this buffer is actually a buffer cancel
1706                          * log item, then decrement the refcount on the
1707                          * one in the table and remove it if this is the
1708                          * last reference.
1709                          */
1710                         if (flags & XFS_BLI_CANCEL) {
1711                                 bcp->bc_refcount--;
1712                                 if (bcp->bc_refcount == 0) {
1713                                         if (prevp == NULL) {
1714                                                 *bucket = bcp->bc_next;
1715                                         } else {
1716                                                 prevp->bc_next = bcp->bc_next;
1717                                         }
1718                                         kmem_free(bcp);
1719                                 }
1720                         }
1721                         return 1;
1722                 }
1723                 prevp = bcp;
1724                 bcp = bcp->bc_next;
1725         }
1726         /*
1727          * We didn't find a corresponding entry in the table, so
1728          * return 0 so that the buffer is NOT cancelled.
1729          */
1730         ASSERT(!(flags & XFS_BLI_CANCEL));
1731         return 0;
1732 }
1733
1734 STATIC int
1735 xlog_recover_do_buffer_pass2(
1736         xlog_t                  *log,
1737         xfs_buf_log_format_t    *buf_f)
1738 {
1739         xfs_daddr_t             blkno = 0;
1740         ushort                  flags = 0;
1741         uint                    len = 0;
1742
1743         switch (buf_f->blf_type) {
1744         case XFS_LI_BUF:
1745                 blkno = buf_f->blf_blkno;
1746                 flags = buf_f->blf_flags;
1747                 len = buf_f->blf_len;
1748                 break;
1749         }
1750
1751         return xlog_check_buffer_cancelled(log, blkno, len, flags);
1752 }
1753
1754 /*
1755  * Perform recovery for a buffer full of inodes.  In these buffers,
1756  * the only data which should be recovered is that which corresponds
1757  * to the di_next_unlinked pointers in the on disk inode structures.
1758  * The rest of the data for the inodes is always logged through the
1759  * inodes themselves rather than the inode buffer and is recovered
1760  * in xlog_recover_do_inode_trans().
1761  *
1762  * The only time when buffers full of inodes are fully recovered is
1763  * when the buffer is full of newly allocated inodes.  In this case
1764  * the buffer will not be marked as an inode buffer and so will be
1765  * sent to xlog_recover_do_reg_buffer() below during recovery.
1766  */
1767 STATIC int
1768 xlog_recover_do_inode_buffer(
1769         xfs_mount_t             *mp,
1770         xlog_recover_item_t     *item,
1771         xfs_buf_t               *bp,
1772         xfs_buf_log_format_t    *buf_f)
1773 {
1774         int                     i;
1775         int                     item_index;
1776         int                     bit;
1777         int                     nbits;
1778         int                     reg_buf_offset;
1779         int                     reg_buf_bytes;
1780         int                     next_unlinked_offset;
1781         int                     inodes_per_buf;
1782         xfs_agino_t             *logged_nextp;
1783         xfs_agino_t             *buffer_nextp;
1784         unsigned int            *data_map = NULL;
1785         unsigned int            map_size = 0;
1786
1787         switch (buf_f->blf_type) {
1788         case XFS_LI_BUF:
1789                 data_map = buf_f->blf_data_map;
1790                 map_size = buf_f->blf_map_size;
1791                 break;
1792         }
1793         /*
1794          * Set the variables corresponding to the current region to
1795          * 0 so that we'll initialize them on the first pass through
1796          * the loop.
1797          */
1798         reg_buf_offset = 0;
1799         reg_buf_bytes = 0;
1800         bit = 0;
1801         nbits = 0;
1802         item_index = 0;
1803         inodes_per_buf = XFS_BUF_COUNT(bp) >> mp->m_sb.sb_inodelog;
1804         for (i = 0; i < inodes_per_buf; i++) {
1805                 next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
1806                         offsetof(xfs_dinode_t, di_next_unlinked);
1807
1808                 while (next_unlinked_offset >=
1809                        (reg_buf_offset + reg_buf_bytes)) {
1810                         /*
1811                          * The next di_next_unlinked field is beyond
1812                          * the current logged region.  Find the next
1813                          * logged region that contains or is beyond
1814                          * the current di_next_unlinked field.
1815                          */
1816                         bit += nbits;
1817                         bit = xfs_next_bit(data_map, map_size, bit);
1818
1819                         /*
1820                          * If there are no more logged regions in the
1821                          * buffer, then we're done.
1822                          */
1823                         if (bit == -1) {
1824                                 return 0;
1825                         }
1826
1827                         nbits = xfs_contig_bits(data_map, map_size,
1828                                                          bit);
1829                         ASSERT(nbits > 0);
1830                         reg_buf_offset = bit << XFS_BLI_SHIFT;
1831                         reg_buf_bytes = nbits << XFS_BLI_SHIFT;
1832                         item_index++;
1833                 }
1834
1835                 /*
1836                  * If the current logged region starts after the current
1837                  * di_next_unlinked field, then move on to the next
1838                  * di_next_unlinked field.
1839                  */
1840                 if (next_unlinked_offset < reg_buf_offset) {
1841                         continue;
1842                 }
1843
1844                 ASSERT(item->ri_buf[item_index].i_addr != NULL);
1845                 ASSERT((item->ri_buf[item_index].i_len % XFS_BLI_CHUNK) == 0);
1846                 ASSERT((reg_buf_offset + reg_buf_bytes) <= XFS_BUF_COUNT(bp));
1847
1848                 /*
1849                  * The current logged region contains a copy of the
1850                  * current di_next_unlinked field.  Extract its value
1851                  * and copy it to the buffer copy.
1852                  */
1853                 logged_nextp = (xfs_agino_t *)
1854                                ((char *)(item->ri_buf[item_index].i_addr) +
1855                                 (next_unlinked_offset - reg_buf_offset));
1856                 if (unlikely(*logged_nextp == 0)) {
1857                         xfs_fs_cmn_err(CE_ALERT, mp,
1858                                 "bad inode buffer log record (ptr = 0x%p, bp = 0x%p).  XFS trying to replay bad (0) inode di_next_unlinked field",
1859                                 item, bp);
1860                         XFS_ERROR_REPORT("xlog_recover_do_inode_buf",
1861                                          XFS_ERRLEVEL_LOW, mp);
1862                         return XFS_ERROR(EFSCORRUPTED);
1863                 }
1864
1865                 buffer_nextp = (xfs_agino_t *)xfs_buf_offset(bp,
1866                                               next_unlinked_offset);
1867                 *buffer_nextp = *logged_nextp;
1868         }
1869
1870         return 0;
1871 }
1872
1873 /*
1874  * Perform a 'normal' buffer recovery.  Each logged region of the
1875  * buffer should be copied over the corresponding region in the
1876  * given buffer.  The bitmap in the buf log format structure indicates
1877  * where to place the logged data.
1878  */
1879 /*ARGSUSED*/
1880 STATIC void
1881 xlog_recover_do_reg_buffer(
1882         xlog_recover_item_t     *item,
1883         xfs_buf_t               *bp,
1884         xfs_buf_log_format_t    *buf_f)
1885 {
1886         int                     i;
1887         int                     bit;
1888         int                     nbits;
1889         unsigned int            *data_map = NULL;
1890         unsigned int            map_size = 0;
1891         int                     error;
1892
1893         switch (buf_f->blf_type) {
1894         case XFS_LI_BUF:
1895                 data_map = buf_f->blf_data_map;
1896                 map_size = buf_f->blf_map_size;
1897                 break;
1898         }
1899         bit = 0;
1900         i = 1;  /* 0 is the buf format structure */
1901         while (1) {
1902                 bit = xfs_next_bit(data_map, map_size, bit);
1903                 if (bit == -1)
1904                         break;
1905                 nbits = xfs_contig_bits(data_map, map_size, bit);
1906                 ASSERT(nbits > 0);
1907                 ASSERT(item->ri_buf[i].i_addr != NULL);
1908                 ASSERT(item->ri_buf[i].i_len % XFS_BLI_CHUNK == 0);
1909                 ASSERT(XFS_BUF_COUNT(bp) >=
1910                        ((uint)bit << XFS_BLI_SHIFT)+(nbits<<XFS_BLI_SHIFT));
1911
1912                 /*
1913                  * Do a sanity check if this is a dquot buffer. Just checking
1914                  * the first dquot in the buffer should do. XXXThis is
1915                  * probably a good thing to do for other buf types also.
1916                  */
1917                 error = 0;
1918                 if (buf_f->blf_flags &
1919                    (XFS_BLI_UDQUOT_BUF|XFS_BLI_PDQUOT_BUF|XFS_BLI_GDQUOT_BUF)) {
1920                         error = xfs_qm_dqcheck((xfs_disk_dquot_t *)
1921                                                item->ri_buf[i].i_addr,
1922                                                -1, 0, XFS_QMOPT_DOWARN,
1923                                                "dquot_buf_recover");
1924                 }
1925                 if (!error)
1926                         memcpy(xfs_buf_offset(bp,
1927                                 (uint)bit << XFS_BLI_SHIFT),    /* dest */
1928                                 item->ri_buf[i].i_addr,         /* source */
1929                                 nbits<<XFS_BLI_SHIFT);          /* length */
1930                 i++;
1931                 bit += nbits;
1932         }
1933
1934         /* Shouldn't be any more regions */
1935         ASSERT(i == item->ri_total);
1936 }
1937
1938 /*
1939  * Do some primitive error checking on ondisk dquot data structures.
1940  */
1941 int
1942 xfs_qm_dqcheck(
1943         xfs_disk_dquot_t *ddq,
1944         xfs_dqid_t       id,
1945         uint             type,    /* used only when IO_dorepair is true */
1946         uint             flags,
1947         char             *str)
1948 {
1949         xfs_dqblk_t      *d = (xfs_dqblk_t *)ddq;
1950         int             errs = 0;
1951
1952         /*
1953          * We can encounter an uninitialized dquot buffer for 2 reasons:
1954          * 1. If we crash while deleting the quotainode(s), and those blks got
1955          *    used for user data. This is because we take the path of regular
1956          *    file deletion; however, the size field of quotainodes is never
1957          *    updated, so all the tricks that we play in itruncate_finish
1958          *    don't quite matter.
1959          *
1960          * 2. We don't play the quota buffers when there's a quotaoff logitem.
1961          *    But the allocation will be replayed so we'll end up with an
1962          *    uninitialized quota block.
1963          *
1964          * This is all fine; things are still consistent, and we haven't lost
1965          * any quota information. Just don't complain about bad dquot blks.
1966          */
1967         if (be16_to_cpu(ddq->d_magic) != XFS_DQUOT_MAGIC) {
1968                 if (flags & XFS_QMOPT_DOWARN)
1969                         cmn_err(CE_ALERT,
1970                         "%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
1971                         str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
1972                 errs++;
1973         }
1974         if (ddq->d_version != XFS_DQUOT_VERSION) {
1975                 if (flags & XFS_QMOPT_DOWARN)
1976                         cmn_err(CE_ALERT,
1977                         "%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
1978                         str, id, ddq->d_version, XFS_DQUOT_VERSION);
1979                 errs++;
1980         }
1981
1982         if (ddq->d_flags != XFS_DQ_USER &&
1983             ddq->d_flags != XFS_DQ_PROJ &&
1984             ddq->d_flags != XFS_DQ_GROUP) {
1985                 if (flags & XFS_QMOPT_DOWARN)
1986                         cmn_err(CE_ALERT,
1987                         "%s : XFS dquot ID 0x%x, unknown flags 0x%x",
1988                         str, id, ddq->d_flags);
1989                 errs++;
1990         }
1991
1992         if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
1993                 if (flags & XFS_QMOPT_DOWARN)
1994                         cmn_err(CE_ALERT,
1995                         "%s : ondisk-dquot 0x%p, ID mismatch: "
1996                         "0x%x expected, found id 0x%x",
1997                         str, ddq, id, be32_to_cpu(ddq->d_id));
1998                 errs++;
1999         }
2000
2001         if (!errs && ddq->d_id) {
2002                 if (ddq->d_blk_softlimit &&
2003                     be64_to_cpu(ddq->d_bcount) >=
2004                                 be64_to_cpu(ddq->d_blk_softlimit)) {
2005                         if (!ddq->d_btimer) {
2006                                 if (flags & XFS_QMOPT_DOWARN)
2007                                         cmn_err(CE_ALERT,
2008                                         "%s : Dquot ID 0x%x (0x%p) "
2009                                         "BLK TIMER NOT STARTED",
2010                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
2011                                 errs++;
2012                         }
2013                 }
2014                 if (ddq->d_ino_softlimit &&
2015                     be64_to_cpu(ddq->d_icount) >=
2016                                 be64_to_cpu(ddq->d_ino_softlimit)) {
2017                         if (!ddq->d_itimer) {
2018                                 if (flags & XFS_QMOPT_DOWARN)
2019                                         cmn_err(CE_ALERT,
2020                                         "%s : Dquot ID 0x%x (0x%p) "
2021                                         "INODE TIMER NOT STARTED",
2022                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
2023                                 errs++;
2024                         }
2025                 }
2026                 if (ddq->d_rtb_softlimit &&
2027                     be64_to_cpu(ddq->d_rtbcount) >=
2028                                 be64_to_cpu(ddq->d_rtb_softlimit)) {
2029                         if (!ddq->d_rtbtimer) {
2030                                 if (flags & XFS_QMOPT_DOWARN)
2031                                         cmn_err(CE_ALERT,
2032                                         "%s : Dquot ID 0x%x (0x%p) "
2033                                         "RTBLK TIMER NOT STARTED",
2034                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
2035                                 errs++;
2036                         }
2037                 }
2038         }
2039
2040         if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
2041                 return errs;
2042
2043         if (flags & XFS_QMOPT_DOWARN)
2044                 cmn_err(CE_NOTE, "Re-initializing dquot ID 0x%x", id);
2045
2046         /*
2047          * Typically, a repair is only requested by quotacheck.
2048          */
2049         ASSERT(id != -1);
2050         ASSERT(flags & XFS_QMOPT_DQREPAIR);
2051         memset(d, 0, sizeof(xfs_dqblk_t));
2052
2053         d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
2054         d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
2055         d->dd_diskdq.d_flags = type;
2056         d->dd_diskdq.d_id = cpu_to_be32(id);
2057
2058         return errs;
2059 }
2060
2061 /*
2062  * Perform a dquot buffer recovery.
2063  * Simple algorithm: if we have found a QUOTAOFF logitem of the same type
2064  * (ie. USR or GRP), then just toss this buffer away; don't recover it.
2065  * Else, treat it as a regular buffer and do recovery.
2066  */
2067 STATIC void
2068 xlog_recover_do_dquot_buffer(
2069         xfs_mount_t             *mp,
2070         xlog_t                  *log,
2071         xlog_recover_item_t     *item,
2072         xfs_buf_t               *bp,
2073         xfs_buf_log_format_t    *buf_f)
2074 {
2075         uint                    type;
2076
2077         /*
2078          * Filesystems are required to send in quota flags at mount time.
2079          */
2080         if (mp->m_qflags == 0) {
2081                 return;
2082         }
2083
2084         type = 0;
2085         if (buf_f->blf_flags & XFS_BLI_UDQUOT_BUF)
2086                 type |= XFS_DQ_USER;
2087         if (buf_f->blf_flags & XFS_BLI_PDQUOT_BUF)
2088                 type |= XFS_DQ_PROJ;
2089         if (buf_f->blf_flags & XFS_BLI_GDQUOT_BUF)
2090                 type |= XFS_DQ_GROUP;
2091         /*
2092          * This type of quotas was turned off, so ignore this buffer
2093          */
2094         if (log->l_quotaoffs_flag & type)
2095                 return;
2096
2097         xlog_recover_do_reg_buffer(item, bp, buf_f);
2098 }
2099
2100 /*
2101  * This routine replays a modification made to a buffer at runtime.
2102  * There are actually two types of buffer, regular and inode, which
2103  * are handled differently.  Inode buffers are handled differently
2104  * in that we only recover a specific set of data from them, namely
2105  * the inode di_next_unlinked fields.  This is because all other inode
2106  * data is actually logged via inode records and any data we replay
2107  * here which overlaps that may be stale.
2108  *
2109  * When meta-data buffers are freed at run time we log a buffer item
2110  * with the XFS_BLI_CANCEL bit set to indicate that previous copies
2111  * of the buffer in the log should not be replayed at recovery time.
2112  * This is so that if the blocks covered by the buffer are reused for
2113  * file data before we crash we don't end up replaying old, freed
2114  * meta-data into a user's file.
2115  *
2116  * To handle the cancellation of buffer log items, we make two passes
2117  * over the log during recovery.  During the first we build a table of
2118  * those buffers which have been cancelled, and during the second we
2119  * only replay those buffers which do not have corresponding cancel
2120  * records in the table.  See xlog_recover_do_buffer_pass[1,2] above
2121  * for more details on the implementation of the table of cancel records.
2122  */
2123 STATIC int
2124 xlog_recover_do_buffer_trans(
2125         xlog_t                  *log,
2126         xlog_recover_item_t     *item,
2127         int                     pass)
2128 {
2129         xfs_buf_log_format_t    *buf_f;
2130         xfs_mount_t             *mp;
2131         xfs_buf_t               *bp;
2132         int                     error;
2133         int                     cancel;
2134         xfs_daddr_t             blkno;
2135         int                     len;
2136         ushort                  flags;
2137
2138         buf_f = (xfs_buf_log_format_t *)item->ri_buf[0].i_addr;
2139
2140         if (pass == XLOG_RECOVER_PASS1) {
2141                 /*
2142                  * In this pass we're only looking for buf items
2143                  * with the XFS_BLI_CANCEL bit set.
2144                  */
2145                 xlog_recover_do_buffer_pass1(log, buf_f);
2146                 return 0;
2147         } else {
2148                 /*
2149                  * In this pass we want to recover all the buffers
2150                  * which have not been cancelled and are not
2151                  * cancellation buffers themselves.  The routine
2152                  * we call here will tell us whether or not to
2153                  * continue with the replay of this buffer.
2154                  */
2155                 cancel = xlog_recover_do_buffer_pass2(log, buf_f);
2156                 if (cancel) {
2157                         return 0;
2158                 }
2159         }
2160         switch (buf_f->blf_type) {
2161         case XFS_LI_BUF:
2162                 blkno = buf_f->blf_blkno;
2163                 len = buf_f->blf_len;
2164                 flags = buf_f->blf_flags;
2165                 break;
2166         default:
2167                 xfs_fs_cmn_err(CE_ALERT, log->l_mp,
2168                         "xfs_log_recover: unknown buffer type 0x%x, logdev %s",
2169                         buf_f->blf_type, log->l_mp->m_logname ?
2170                         log->l_mp->m_logname : "internal");
2171                 XFS_ERROR_REPORT("xlog_recover_do_buffer_trans",
2172                                  XFS_ERRLEVEL_LOW, log->l_mp);
2173                 return XFS_ERROR(EFSCORRUPTED);
2174         }
2175
2176         mp = log->l_mp;
2177         if (flags & XFS_BLI_INODE_BUF) {
2178                 bp = xfs_buf_read_flags(mp->m_ddev_targp, blkno, len,
2179                                                                 XFS_BUF_LOCK);
2180         } else {
2181                 bp = xfs_buf_read(mp->m_ddev_targp, blkno, len, 0);
2182         }
2183         if (XFS_BUF_ISERROR(bp)) {
2184                 xfs_ioerror_alert("xlog_recover_do..(read#1)", log->l_mp,
2185                                   bp, blkno);
2186                 error = XFS_BUF_GETERROR(bp);
2187                 xfs_buf_relse(bp);
2188                 return error;
2189         }
2190
2191         error = 0;
2192         if (flags & XFS_BLI_INODE_BUF) {
2193                 error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
2194         } else if (flags &
2195                   (XFS_BLI_UDQUOT_BUF|XFS_BLI_PDQUOT_BUF|XFS_BLI_GDQUOT_BUF)) {
2196                 xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
2197         } else {
2198                 xlog_recover_do_reg_buffer(item, bp, buf_f);
2199         }
2200         if (error)
2201                 return XFS_ERROR(error);
2202
2203         /*
2204          * Perform delayed write on the buffer.  Asynchronous writes will be
2205          * slower when taking into account all the buffers to be flushed.
2206          *
2207          * Also make sure that only inode buffers with good sizes stay in
2208          * the buffer cache.  The kernel moves inodes in buffers of 1 block
2209          * or XFS_INODE_CLUSTER_SIZE bytes, whichever is bigger.  The inode
2210          * buffers in the log can be a different size if the log was generated
2211          * by an older kernel using unclustered inode buffers or a newer kernel
2212          * running with a different inode cluster size.  Regardless, if the
2213          * the inode buffer size isn't MAX(blocksize, XFS_INODE_CLUSTER_SIZE)
2214          * for *our* value of XFS_INODE_CLUSTER_SIZE, then we need to keep
2215          * the buffer out of the buffer cache so that the buffer won't
2216          * overlap with future reads of those inodes.
2217          */
2218         if (XFS_DINODE_MAGIC ==
2219             be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
2220             (XFS_BUF_COUNT(bp) != MAX(log->l_mp->m_sb.sb_blocksize,
2221                         (__uint32_t)XFS_INODE_CLUSTER_SIZE(log->l_mp)))) {
2222                 XFS_BUF_STALE(bp);
2223                 error = xfs_bwrite(mp, bp);
2224         } else {
2225                 ASSERT(XFS_BUF_FSPRIVATE(bp, void *) == NULL ||
2226                        XFS_BUF_FSPRIVATE(bp, xfs_mount_t *) == mp);
2227                 XFS_BUF_SET_FSPRIVATE(bp, mp);
2228                 XFS_BUF_SET_IODONE_FUNC(bp, xlog_recover_iodone);
2229                 xfs_bdwrite(mp, bp);
2230         }
2231
2232         return (error);
2233 }
2234
2235 STATIC int
2236 xlog_recover_do_inode_trans(
2237         xlog_t                  *log,
2238         xlog_recover_item_t     *item,
2239         int                     pass)
2240 {
2241         xfs_inode_log_format_t  *in_f;
2242         xfs_mount_t             *mp;
2243         xfs_buf_t               *bp;
2244         xfs_imap_t              imap;
2245         xfs_dinode_t            *dip;
2246         xfs_ino_t               ino;
2247         int                     len;
2248         xfs_caddr_t             src;
2249         xfs_caddr_t             dest;
2250         int                     error;
2251         int                     attr_index;
2252         uint                    fields;
2253         xfs_icdinode_t          *dicp;
2254         int                     need_free = 0;
2255
2256         if (pass == XLOG_RECOVER_PASS1) {
2257                 return 0;
2258         }
2259
2260         if (item->ri_buf[0].i_len == sizeof(xfs_inode_log_format_t)) {
2261                 in_f = (xfs_inode_log_format_t *)item->ri_buf[0].i_addr;
2262         } else {
2263                 in_f = (xfs_inode_log_format_t *)kmem_alloc(
2264                         sizeof(xfs_inode_log_format_t), KM_SLEEP);
2265                 need_free = 1;
2266                 error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f);
2267                 if (error)
2268                         goto error;
2269         }
2270         ino = in_f->ilf_ino;
2271         mp = log->l_mp;
2272         if (ITEM_TYPE(item) == XFS_LI_INODE) {
2273                 imap.im_blkno = (xfs_daddr_t)in_f->ilf_blkno;
2274                 imap.im_len = in_f->ilf_len;
2275                 imap.im_boffset = in_f->ilf_boffset;
2276         } else {
2277                 /*
2278                  * It's an old inode format record.  We don't know where
2279                  * its cluster is located on disk, and we can't allow
2280                  * xfs_imap() to figure it out because the inode btrees
2281                  * are not ready to be used.  Therefore do not pass the
2282                  * XFS_IMAP_LOOKUP flag to xfs_imap().  This will give
2283                  * us only the single block in which the inode lives
2284                  * rather than its cluster, so we must make sure to
2285                  * invalidate the buffer when we write it out below.
2286                  */
2287                 imap.im_blkno = 0;
2288                 error = xfs_imap(log->l_mp, NULL, ino, &imap, 0);
2289                 if (error)
2290                         goto error;
2291         }
2292
2293         /*
2294          * Inode buffers can be freed, look out for it,
2295          * and do not replay the inode.
2296          */
2297         if (xlog_check_buffer_cancelled(log, imap.im_blkno, imap.im_len, 0)) {
2298                 error = 0;
2299                 goto error;
2300         }
2301
2302         bp = xfs_buf_read_flags(mp->m_ddev_targp, imap.im_blkno, imap.im_len,
2303                                                                 XFS_BUF_LOCK);
2304         if (XFS_BUF_ISERROR(bp)) {
2305                 xfs_ioerror_alert("xlog_recover_do..(read#2)", mp,
2306                                   bp, imap.im_blkno);
2307                 error = XFS_BUF_GETERROR(bp);
2308                 xfs_buf_relse(bp);
2309                 goto error;
2310         }
2311         error = 0;
2312         ASSERT(in_f->ilf_fields & XFS_ILOG_CORE);
2313         dip = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
2314
2315         /*
2316          * Make sure the place we're flushing out to really looks
2317          * like an inode!
2318          */
2319         if (unlikely(be16_to_cpu(dip->di_core.di_magic) != XFS_DINODE_MAGIC)) {
2320                 xfs_buf_relse(bp);
2321                 xfs_fs_cmn_err(CE_ALERT, mp,
2322                         "xfs_inode_recover: Bad inode magic number, dino ptr = 0x%p, dino bp = 0x%p, ino = %Ld",
2323                         dip, bp, ino);
2324                 XFS_ERROR_REPORT("xlog_recover_do_inode_trans(1)",
2325                                  XFS_ERRLEVEL_LOW, mp);
2326                 error = EFSCORRUPTED;
2327                 goto error;
2328         }
2329         dicp = (xfs_icdinode_t *)(item->ri_buf[1].i_addr);
2330         if (unlikely(dicp->di_magic != XFS_DINODE_MAGIC)) {
2331                 xfs_buf_relse(bp);
2332                 xfs_fs_cmn_err(CE_ALERT, mp,
2333                         "xfs_inode_recover: Bad inode log record, rec ptr 0x%p, ino %Ld",
2334                         item, ino);
2335                 XFS_ERROR_REPORT("xlog_recover_do_inode_trans(2)",
2336                                  XFS_ERRLEVEL_LOW, mp);
2337                 error = EFSCORRUPTED;
2338                 goto error;
2339         }
2340
2341         /* Skip replay when the on disk inode is newer than the log one */
2342         if (dicp->di_flushiter < be16_to_cpu(dip->di_core.di_flushiter)) {
2343                 /*
2344                  * Deal with the wrap case, DI_MAX_FLUSH is less
2345                  * than smaller numbers
2346                  */
2347                 if (be16_to_cpu(dip->di_core.di_flushiter) == DI_MAX_FLUSH &&
2348                     dicp->di_flushiter < (DI_MAX_FLUSH >> 1)) {
2349                         /* do nothing */
2350                 } else {
2351                         xfs_buf_relse(bp);
2352                         error = 0;
2353                         goto error;
2354                 }
2355         }
2356         /* Take the opportunity to reset the flush iteration count */
2357         dicp->di_flushiter = 0;
2358
2359         if (unlikely((dicp->di_mode & S_IFMT) == S_IFREG)) {
2360                 if ((dicp->di_format != XFS_DINODE_FMT_EXTENTS) &&
2361                     (dicp->di_format != XFS_DINODE_FMT_BTREE)) {
2362                         XFS_CORRUPTION_ERROR("xlog_recover_do_inode_trans(3)",
2363                                          XFS_ERRLEVEL_LOW, mp, dicp);
2364                         xfs_buf_relse(bp);
2365                         xfs_fs_cmn_err(CE_ALERT, mp,
2366                                 "xfs_inode_recover: Bad regular inode log record, rec ptr 0x%p, ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
2367                                 item, dip, bp, ino);
2368                         error = EFSCORRUPTED;
2369                         goto error;
2370                 }
2371         } else if (unlikely((dicp->di_mode & S_IFMT) == S_IFDIR)) {
2372                 if ((dicp->di_format != XFS_DINODE_FMT_EXTENTS) &&
2373                     (dicp->di_format != XFS_DINODE_FMT_BTREE) &&
2374                     (dicp->di_format != XFS_DINODE_FMT_LOCAL)) {
2375                         XFS_CORRUPTION_ERROR("xlog_recover_do_inode_trans(4)",
2376                                              XFS_ERRLEVEL_LOW, mp, dicp);
2377                         xfs_buf_relse(bp);
2378                         xfs_fs_cmn_err(CE_ALERT, mp,
2379                                 "xfs_inode_recover: Bad dir inode log record, rec ptr 0x%p, ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
2380                                 item, dip, bp, ino);
2381                         error = EFSCORRUPTED;
2382                         goto error;
2383                 }
2384         }
2385         if (unlikely(dicp->di_nextents + dicp->di_anextents > dicp->di_nblocks)){
2386                 XFS_CORRUPTION_ERROR("xlog_recover_do_inode_trans(5)",
2387                                      XFS_ERRLEVEL_LOW, mp, dicp);
2388                 xfs_buf_relse(bp);
2389                 xfs_fs_cmn_err(CE_ALERT, mp,
2390                         "xfs_inode_recover: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, dino bp 0x%p, ino %Ld, total extents = %d, nblocks = %Ld",
2391                         item, dip, bp, ino,
2392                         dicp->di_nextents + dicp->di_anextents,
2393                         dicp->di_nblocks);
2394                 error = EFSCORRUPTED;
2395                 goto error;
2396         }
2397         if (unlikely(dicp->di_forkoff > mp->m_sb.sb_inodesize)) {
2398                 XFS_CORRUPTION_ERROR("xlog_recover_do_inode_trans(6)",
2399                                      XFS_ERRLEVEL_LOW, mp, dicp);
2400                 xfs_buf_relse(bp);
2401                 xfs_fs_cmn_err(CE_ALERT, mp,
2402                         "xfs_inode_recover: Bad inode log rec ptr 0x%p, dino ptr 0x%p, dino bp 0x%p, ino %Ld, forkoff 0x%x",
2403                         item, dip, bp, ino, dicp->di_forkoff);
2404                 error = EFSCORRUPTED;
2405                 goto error;
2406         }
2407         if (unlikely(item->ri_buf[1].i_len > sizeof(xfs_dinode_core_t))) {
2408                 XFS_CORRUPTION_ERROR("xlog_recover_do_inode_trans(7)",
2409                                      XFS_ERRLEVEL_LOW, mp, dicp);
2410                 xfs_buf_relse(bp);
2411                 xfs_fs_cmn_err(CE_ALERT, mp,
2412                         "xfs_inode_recover: Bad inode log record length %d, rec ptr 0x%p",
2413                         item->ri_buf[1].i_len, item);
2414                 error = EFSCORRUPTED;
2415                 goto error;
2416         }
2417
2418         /* The core is in in-core format */
2419         xfs_dinode_to_disk(&dip->di_core,
2420                 (xfs_icdinode_t *)item->ri_buf[1].i_addr);
2421
2422         /* the rest is in on-disk format */
2423         if (item->ri_buf[1].i_len > sizeof(xfs_dinode_core_t)) {
2424                 memcpy((xfs_caddr_t) dip + sizeof(xfs_dinode_core_t),
2425                         item->ri_buf[1].i_addr + sizeof(xfs_dinode_core_t),
2426                         item->ri_buf[1].i_len  - sizeof(xfs_dinode_core_t));
2427         }
2428
2429         fields = in_f->ilf_fields;
2430         switch (fields & (XFS_ILOG_DEV | XFS_ILOG_UUID)) {
2431         case XFS_ILOG_DEV:
2432                 dip->di_u.di_dev = cpu_to_be32(in_f->ilf_u.ilfu_rdev);
2433                 break;
2434         case XFS_ILOG_UUID:
2435                 dip->di_u.di_muuid = in_f->ilf_u.ilfu_uuid;
2436                 break;
2437         }
2438
2439         if (in_f->ilf_size == 2)
2440                 goto write_inode_buffer;
2441         len = item->ri_buf[2].i_len;
2442         src = item->ri_buf[2].i_addr;
2443         ASSERT(in_f->ilf_size <= 4);
2444         ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK));
2445         ASSERT(!(fields & XFS_ILOG_DFORK) ||
2446                (len == in_f->ilf_dsize));
2447
2448         switch (fields & XFS_ILOG_DFORK) {
2449         case XFS_ILOG_DDATA:
2450         case XFS_ILOG_DEXT:
2451                 memcpy(&dip->di_u, src, len);
2452                 break;
2453
2454         case XFS_ILOG_DBROOT:
2455                 xfs_bmbt_to_bmdr(mp, (xfs_bmbt_block_t *)src, len,
2456                                  &(dip->di_u.di_bmbt),
2457                                  XFS_DFORK_DSIZE(dip, mp));
2458                 break;
2459
2460         default:
2461                 /*
2462                  * There are no data fork flags set.
2463                  */
2464                 ASSERT((fields & XFS_ILOG_DFORK) == 0);
2465                 break;
2466         }
2467
2468         /*
2469          * If we logged any attribute data, recover it.  There may or
2470          * may not have been any other non-core data logged in this
2471          * transaction.
2472          */
2473         if (in_f->ilf_fields & XFS_ILOG_AFORK) {
2474                 if (in_f->ilf_fields & XFS_ILOG_DFORK) {
2475                         attr_index = 3;
2476                 } else {
2477                         attr_index = 2;
2478                 }
2479                 len = item->ri_buf[attr_index].i_len;
2480                 src = item->ri_buf[attr_index].i_addr;
2481                 ASSERT(len == in_f->ilf_asize);
2482
2483                 switch (in_f->ilf_fields & XFS_ILOG_AFORK) {
2484                 case XFS_ILOG_ADATA:
2485                 case XFS_ILOG_AEXT:
2486                         dest = XFS_DFORK_APTR(dip);
2487                         ASSERT(len <= XFS_DFORK_ASIZE(dip, mp));
2488                         memcpy(dest, src, len);
2489                         break;
2490
2491                 case XFS_ILOG_ABROOT:
2492                         dest = XFS_DFORK_APTR(dip);
2493                         xfs_bmbt_to_bmdr(mp, (xfs_bmbt_block_t *)src, len,
2494                                          (xfs_bmdr_block_t*)dest,
2495                                          XFS_DFORK_ASIZE(dip, mp));
2496                         break;
2497
2498                 default:
2499                         xlog_warn("XFS: xlog_recover_do_inode_trans: Invalid flag");
2500                         ASSERT(0);
2501                         xfs_buf_relse(bp);
2502                         error = EIO;
2503                         goto error;
2504                 }
2505         }
2506
2507 write_inode_buffer:
2508         if (ITEM_TYPE(item) == XFS_LI_INODE) {
2509                 ASSERT(XFS_BUF_FSPRIVATE(bp, void *) == NULL ||
2510                        XFS_BUF_FSPRIVATE(bp, xfs_mount_t *) == mp);
2511                 XFS_BUF_SET_FSPRIVATE(bp, mp);
2512                 XFS_BUF_SET_IODONE_FUNC(bp, xlog_recover_iodone);
2513                 xfs_bdwrite(mp, bp);
2514         } else {
2515                 XFS_BUF_STALE(bp);
2516                 error = xfs_bwrite(mp, bp);
2517         }
2518
2519 error:
2520         if (need_free)
2521                 kmem_free(in_f);
2522         return XFS_ERROR(error);
2523 }
2524
2525 /*
2526  * Recover QUOTAOFF records. We simply make a note of it in the xlog_t
2527  * structure, so that we know not to do any dquot item or dquot buffer recovery,
2528  * of that type.
2529  */
2530 STATIC int
2531 xlog_recover_do_quotaoff_trans(
2532         xlog_t                  *log,
2533         xlog_recover_item_t     *item,
2534         int                     pass)
2535 {
2536         xfs_qoff_logformat_t    *qoff_f;
2537
2538         if (pass == XLOG_RECOVER_PASS2) {
2539                 return (0);
2540         }
2541
2542         qoff_f = (xfs_qoff_logformat_t *)item->ri_buf[0].i_addr;
2543         ASSERT(qoff_f);
2544
2545         /*
2546          * The logitem format's flag tells us if this was user quotaoff,
2547          * group/project quotaoff or both.
2548          */
2549         if (qoff_f->qf_flags & XFS_UQUOTA_ACCT)
2550                 log->l_quotaoffs_flag |= XFS_DQ_USER;
2551         if (qoff_f->qf_flags & XFS_PQUOTA_ACCT)
2552                 log->l_quotaoffs_flag |= XFS_DQ_PROJ;
2553         if (qoff_f->qf_flags & XFS_GQUOTA_ACCT)
2554                 log->l_quotaoffs_flag |= XFS_DQ_GROUP;
2555
2556         return (0);
2557 }
2558
2559 /*
2560  * Recover a dquot record
2561  */
2562 STATIC int
2563 xlog_recover_do_dquot_trans(
2564         xlog_t                  *log,
2565         xlog_recover_item_t     *item,
2566         int                     pass)
2567 {
2568         xfs_mount_t             *mp;
2569         xfs_buf_t               *bp;
2570         struct xfs_disk_dquot   *ddq, *recddq;
2571         int                     error;
2572         xfs_dq_logformat_t      *dq_f;
2573         uint                    type;
2574
2575         if (pass == XLOG_RECOVER_PASS1) {
2576                 return 0;
2577         }
2578         mp = log->l_mp;
2579
2580         /*
2581          * Filesystems are required to send in quota flags at mount time.
2582          */
2583         if (mp->m_qflags == 0)
2584                 return (0);
2585
2586         recddq = (xfs_disk_dquot_t *)item->ri_buf[1].i_addr;
2587         ASSERT(recddq);
2588         /*
2589          * This type of quotas was turned off, so ignore this record.
2590          */
2591         type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
2592         ASSERT(type);
2593         if (log->l_quotaoffs_flag & type)
2594                 return (0);
2595
2596         /*
2597          * At this point we know that quota was _not_ turned off.
2598          * Since the mount flags are not indicating to us otherwise, this
2599          * must mean that quota is on, and the dquot needs to be replayed.
2600          * Remember that we may not have fully recovered the superblock yet,
2601          * so we can't do the usual trick of looking at the SB quota bits.
2602          *
2603          * The other possibility, of course, is that the quota subsystem was
2604          * removed since the last mount - ENOSYS.
2605          */
2606         dq_f = (xfs_dq_logformat_t *)item->ri_buf[0].i_addr;
2607         ASSERT(dq_f);
2608         if ((error = xfs_qm_dqcheck(recddq,
2609                            dq_f->qlf_id,
2610                            0, XFS_QMOPT_DOWARN,
2611                            "xlog_recover_do_dquot_trans (log copy)"))) {
2612                 return XFS_ERROR(EIO);
2613         }
2614         ASSERT(dq_f->qlf_len == 1);
2615
2616         error = xfs_read_buf(mp, mp->m_ddev_targp,
2617                              dq_f->qlf_blkno,
2618                              XFS_FSB_TO_BB(mp, dq_f->qlf_len),
2619                              0, &bp);
2620         if (error) {
2621                 xfs_ioerror_alert("xlog_recover_do..(read#3)", mp,
2622                                   bp, dq_f->qlf_blkno);
2623                 return error;
2624         }
2625         ASSERT(bp);
2626         ddq = (xfs_disk_dquot_t *)xfs_buf_offset(bp, dq_f->qlf_boffset);
2627
2628         /*
2629          * At least the magic num portion should be on disk because this
2630          * was among a chunk of dquots created earlier, and we did some
2631          * minimal initialization then.
2632          */
2633         if (xfs_qm_dqcheck(ddq, dq_f->qlf_id, 0, XFS_QMOPT_DOWARN,
2634                            "xlog_recover_do_dquot_trans")) {
2635                 xfs_buf_relse(bp);
2636                 return XFS_ERROR(EIO);
2637         }
2638
2639         memcpy(ddq, recddq, item->ri_buf[1].i_len);
2640
2641         ASSERT(dq_f->qlf_size == 2);
2642         ASSERT(XFS_BUF_FSPRIVATE(bp, void *) == NULL ||
2643                XFS_BUF_FSPRIVATE(bp, xfs_mount_t *) == mp);
2644         XFS_BUF_SET_FSPRIVATE(bp, mp);
2645         XFS_BUF_SET_IODONE_FUNC(bp, xlog_recover_iodone);
2646         xfs_bdwrite(mp, bp);
2647
2648         return (0);
2649 }
2650
2651 /*
2652  * This routine is called to create an in-core extent free intent
2653  * item from the efi format structure which was logged on disk.
2654  * It allocates an in-core efi, copies the extents from the format
2655  * structure into it, and adds the efi to the AIL with the given
2656  * LSN.
2657  */
2658 STATIC int
2659 xlog_recover_do_efi_trans(
2660         xlog_t                  *log,
2661         xlog_recover_item_t     *item,
2662         xfs_lsn_t               lsn,
2663         int                     pass)
2664 {
2665         int                     error;
2666         xfs_mount_t             *mp;
2667         xfs_efi_log_item_t      *efip;
2668         xfs_efi_log_format_t    *efi_formatp;
2669
2670         if (pass == XLOG_RECOVER_PASS1) {
2671                 return 0;
2672         }
2673
2674         efi_formatp = (xfs_efi_log_format_t *)item->ri_buf[0].i_addr;
2675
2676         mp = log->l_mp;
2677         efip = xfs_efi_init(mp, efi_formatp->efi_nextents);
2678         if ((error = xfs_efi_copy_format(&(item->ri_buf[0]),
2679                                          &(efip->efi_format)))) {
2680                 xfs_efi_item_free(efip);
2681                 return error;
2682         }
2683         efip->efi_next_extent = efi_formatp->efi_nextents;
2684         efip->efi_flags |= XFS_EFI_COMMITTED;
2685
2686         spin_lock(&mp->m_ail_lock);
2687         /*
2688          * xfs_trans_update_ail() drops the AIL lock.
2689          */
2690         xfs_trans_update_ail(mp, (xfs_log_item_t *)efip, lsn);
2691         return 0;
2692 }
2693
2694
2695 /*
2696  * This routine is called when an efd format structure is found in
2697  * a committed transaction in the log.  It's purpose is to cancel
2698  * the corresponding efi if it was still in the log.  To do this
2699  * it searches the AIL for the efi with an id equal to that in the
2700  * efd format structure.  If we find it, we remove the efi from the
2701  * AIL and free it.
2702  */
2703 STATIC void
2704 xlog_recover_do_efd_trans(
2705         xlog_t                  *log,
2706         xlog_recover_item_t     *item,
2707         int                     pass)
2708 {
2709         xfs_mount_t             *mp;
2710         xfs_efd_log_format_t    *efd_formatp;
2711         xfs_efi_log_item_t      *efip = NULL;
2712         xfs_log_item_t          *lip;
2713         int                     gen;
2714         __uint64_t              efi_id;
2715
2716         if (pass == XLOG_RECOVER_PASS1) {
2717                 return;
2718         }
2719
2720         efd_formatp = (xfs_efd_log_format_t *)item->ri_buf[0].i_addr;
2721         ASSERT((item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_32_t) +
2722                 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_32_t)))) ||
2723                (item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_64_t) +
2724                 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_64_t)))));
2725         efi_id = efd_formatp->efd_efi_id;
2726
2727         /*
2728          * Search for the efi with the id in the efd format structure
2729          * in the AIL.
2730          */
2731         mp = log->l_mp;
2732         spin_lock(&mp->m_ail_lock);
2733         lip = xfs_trans_first_ail(mp, &gen);
2734         while (lip != NULL) {
2735                 if (lip->li_type == XFS_LI_EFI) {
2736                         efip = (xfs_efi_log_item_t *)lip;
2737                         if (efip->efi_format.efi_id == efi_id) {
2738                                 /*
2739                                  * xfs_trans_delete_ail() drops the
2740                                  * AIL lock.
2741                                  */
2742                                 xfs_trans_delete_ail(mp, lip);
2743                                 xfs_efi_item_free(efip);
2744                                 return;
2745                         }
2746                 }
2747                 lip = xfs_trans_next_ail(mp, lip, &gen, NULL);
2748         }
2749         spin_unlock(&mp->m_ail_lock);
2750 }
2751
2752 /*
2753  * Perform the transaction
2754  *
2755  * If the transaction modifies a buffer or inode, do it now.  Otherwise,
2756  * EFIs and EFDs get queued up by adding entries into the AIL for them.
2757  */
2758 STATIC int
2759 xlog_recover_do_trans(
2760         xlog_t                  *log,
2761         xlog_recover_t          *trans,
2762         int                     pass)
2763 {
2764         int                     error = 0;
2765         xlog_recover_item_t     *item, *first_item;
2766
2767         if ((error = xlog_recover_reorder_trans(trans)))
2768                 return error;
2769         first_item = item = trans->r_itemq;
2770         do {
2771                 /*
2772                  * we don't need to worry about the block number being
2773                  * truncated in > 1 TB buffers because in user-land,
2774                  * we're now n32 or 64-bit so xfs_daddr_t is 64-bits so
2775                  * the blknos will get through the user-mode buffer
2776                  * cache properly.  The only bad case is o32 kernels
2777                  * where xfs_daddr_t is 32-bits but mount will warn us
2778                  * off a > 1 TB filesystem before we get here.
2779                  */
2780                 if ((ITEM_TYPE(item) == XFS_LI_BUF)) {
2781                         if  ((error = xlog_recover_do_buffer_trans(log, item,
2782                                                                  pass)))
2783                                 break;
2784                 } else if ((ITEM_TYPE(item) == XFS_LI_INODE)) {
2785                         if ((error = xlog_recover_do_inode_trans(log, item,
2786                                                                 pass)))
2787                                 break;
2788                 } else if (ITEM_TYPE(item) == XFS_LI_EFI) {
2789                         if ((error = xlog_recover_do_efi_trans(log, item, trans->r_lsn,
2790                                                   pass)))
2791                                 break;
2792                 } else if (ITEM_TYPE(item) == XFS_LI_EFD) {
2793                         xlog_recover_do_efd_trans(log, item, pass);
2794                 } else if (ITEM_TYPE(item) == XFS_LI_DQUOT) {
2795                         if ((error = xlog_recover_do_dquot_trans(log, item,
2796                                                                    pass)))
2797                                         break;
2798                 } else if ((ITEM_TYPE(item) == XFS_LI_QUOTAOFF)) {
2799                         if ((error = xlog_recover_do_quotaoff_trans(log, item,
2800                                                                    pass)))
2801                                         break;
2802                 } else {
2803                         xlog_warn("XFS: xlog_recover_do_trans");
2804                         ASSERT(0);
2805                         error = XFS_ERROR(EIO);
2806                         break;
2807                 }
2808                 item = item->ri_next;
2809         } while (first_item != item);
2810
2811         return error;
2812 }
2813
2814 /*
2815  * Free up any resources allocated by the transaction
2816  *
2817  * Remember that EFIs, EFDs, and IUNLINKs are handled later.
2818  */
2819 STATIC void
2820 xlog_recover_free_trans(
2821         xlog_recover_t          *trans)
2822 {
2823         xlog_recover_item_t     *first_item, *item, *free_item;
2824         int                     i;
2825
2826         item = first_item = trans->r_itemq;
2827         do {
2828                 free_item = item;
2829                 item = item->ri_next;
2830                  /* Free the regions in the item. */
2831                 for (i = 0; i < free_item->ri_cnt; i++) {
2832                         kmem_free(free_item->ri_buf[i].i_addr);
2833                 }
2834                 /* Free the item itself */
2835                 kmem_free(free_item->ri_buf);
2836                 kmem_free(free_item);
2837         } while (first_item != item);
2838         /* Free the transaction recover structure */
2839         kmem_free(trans);
2840 }
2841
2842 STATIC int
2843 xlog_recover_commit_trans(
2844         xlog_t                  *log,
2845         xlog_recover_t          **q,
2846         xlog_recover_t          *trans,
2847         int                     pass)
2848 {
2849         int                     error;
2850
2851         if ((error = xlog_recover_unlink_tid(q, trans)))
2852                 return error;
2853         if ((error = xlog_recover_do_trans(log, trans, pass)))
2854                 return error;
2855         xlog_recover_free_trans(trans);                 /* no error */
2856         return 0;
2857 }
2858
2859 STATIC int
2860 xlog_recover_unmount_trans(
2861         xlog_recover_t          *trans)
2862 {
2863         /* Do nothing now */
2864         xlog_warn("XFS: xlog_recover_unmount_trans: Unmount LR");
2865         return 0;
2866 }
2867
2868 /*
2869  * There are two valid states of the r_state field.  0 indicates that the
2870  * transaction structure is in a normal state.  We have either seen the
2871  * start of the transaction or the last operation we added was not a partial
2872  * operation.  If the last operation we added to the transaction was a
2873  * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
2874  *
2875  * NOTE: skip LRs with 0 data length.
2876  */
2877 STATIC int
2878 xlog_recover_process_data(
2879         xlog_t                  *log,
2880         xlog_recover_t          *rhash[],
2881         xlog_rec_header_t       *rhead,
2882         xfs_caddr_t             dp,
2883         int                     pass)
2884 {
2885         xfs_caddr_t             lp;
2886         int                     num_logops;
2887         xlog_op_header_t        *ohead;
2888         xlog_recover_t          *trans;
2889         xlog_tid_t              tid;
2890         int                     error;
2891         unsigned long           hash;
2892         uint                    flags;
2893
2894         lp = dp + be32_to_cpu(rhead->h_len);
2895         num_logops = be32_to_cpu(rhead->h_num_logops);
2896
2897         /* check the log format matches our own - else we can't recover */
2898         if (xlog_header_check_recover(log->l_mp, rhead))
2899                 return (XFS_ERROR(EIO));
2900
2901         while ((dp < lp) && num_logops) {
2902                 ASSERT(dp + sizeof(xlog_op_header_t) <= lp);
2903                 ohead = (xlog_op_header_t *)dp;
2904                 dp += sizeof(xlog_op_header_t);
2905                 if (ohead->oh_clientid != XFS_TRANSACTION &&
2906                     ohead->oh_clientid != XFS_LOG) {
2907                         xlog_warn(
2908                 "XFS: xlog_recover_process_data: bad clientid");
2909                         ASSERT(0);
2910                         return (XFS_ERROR(EIO));
2911                 }
2912                 tid = be32_to_cpu(ohead->oh_tid);
2913                 hash = XLOG_RHASH(tid);
2914                 trans = xlog_recover_find_tid(rhash[hash], tid);
2915                 if (trans == NULL) {               /* not found; add new tid */
2916                         if (ohead->oh_flags & XLOG_START_TRANS)
2917                                 xlog_recover_new_tid(&rhash[hash], tid,
2918                                         be64_to_cpu(rhead->h_lsn));
2919                 } else {
2920                         if (dp + be32_to_cpu(ohead->oh_len) > lp) {
2921                                 xlog_warn(
2922                         "XFS: xlog_recover_process_data: bad length");
2923                                 WARN_ON(1);
2924                                 return (XFS_ERROR(EIO));
2925                         }
2926                         flags = ohead->oh_flags & ~XLOG_END_TRANS;
2927                         if (flags & XLOG_WAS_CONT_TRANS)
2928                                 flags &= ~XLOG_CONTINUE_TRANS;
2929                         switch (flags) {
2930                         case XLOG_COMMIT_TRANS:
2931                                 error = xlog_recover_commit_trans(log,
2932                                                 &rhash[hash], trans, pass);
2933                                 break;
2934                         case XLOG_UNMOUNT_TRANS:
2935                                 error = xlog_recover_unmount_trans(trans);
2936                                 break;
2937                         case XLOG_WAS_CONT_TRANS:
2938                                 error = xlog_recover_add_to_cont_trans(trans,
2939                                                 dp, be32_to_cpu(ohead->oh_len));
2940                                 break;
2941                         case XLOG_START_TRANS:
2942                                 xlog_warn(
2943                         "XFS: xlog_recover_process_data: bad transaction");
2944                                 ASSERT(0);
2945                                 error = XFS_ERROR(EIO);
2946                                 break;
2947                         case 0:
2948                         case XLOG_CONTINUE_TRANS:
2949                                 error = xlog_recover_add_to_trans(trans,
2950                                                 dp, be32_to_cpu(ohead->oh_len));
2951                                 break;
2952                         default:
2953                                 xlog_warn(
2954                         "XFS: xlog_recover_process_data: bad flag");
2955                                 ASSERT(0);
2956                                 error = XFS_ERROR(EIO);
2957                                 break;
2958                         }
2959                         if (error)
2960                                 return error;
2961                 }
2962                 dp += be32_to_cpu(ohead->oh_len);
2963                 num_logops--;
2964         }
2965         return 0;
2966 }
2967
2968 /*
2969  * Process an extent free intent item that was recovered from
2970  * the log.  We need to free the extents that it describes.
2971  */
2972 STATIC int
2973 xlog_recover_process_efi(
2974         xfs_mount_t             *mp,
2975         xfs_efi_log_item_t      *efip)
2976 {
2977         xfs_efd_log_item_t      *efdp;
2978         xfs_trans_t             *tp;
2979         int                     i;
2980         int                     error = 0;
2981         xfs_extent_t            *extp;
2982         xfs_fsblock_t           startblock_fsb;
2983
2984         ASSERT(!(efip->efi_flags & XFS_EFI_RECOVERED));
2985
2986         /*
2987          * First check the validity of the extents described by the
2988          * EFI.  If any are bad, then assume that all are bad and
2989          * just toss the EFI.
2990          */
2991         for (i = 0; i < efip->efi_format.efi_nextents; i++) {
2992                 extp = &(efip->efi_format.efi_extents[i]);
2993                 startblock_fsb = XFS_BB_TO_FSB(mp,
2994                                    XFS_FSB_TO_DADDR(mp, extp->ext_start));
2995                 if ((startblock_fsb == 0) ||
2996                     (extp->ext_len == 0) ||
2997                     (startblock_fsb >= mp->m_sb.sb_dblocks) ||
2998                     (extp->ext_len >= mp->m_sb.sb_agblocks)) {
2999                         /*
3000                          * This will pull the EFI from the AIL and
3001                          * free the memory associated with it.
3002                          */
3003                         xfs_efi_release(efip, efip->efi_format.efi_nextents);
3004                         return XFS_ERROR(EIO);
3005                 }
3006         }
3007
3008         tp = xfs_trans_alloc(mp, 0);
3009         error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0, 0, 0);
3010         if (error)
3011                 goto abort_error;
3012         efdp = xfs_trans_get_efd(tp, efip, efip->efi_format.efi_nextents);
3013
3014         for (i = 0; i < efip->efi_format.efi_nextents; i++) {
3015                 extp = &(efip->efi_format.efi_extents[i]);
3016                 error = xfs_free_extent(tp, extp->ext_start, extp->ext_len);
3017                 if (error)
3018                         goto abort_error;
3019                 xfs_trans_log_efd_extent(tp, efdp, extp->ext_start,
3020                                          extp->ext_len);
3021         }
3022
3023         efip->efi_flags |= XFS_EFI_RECOVERED;
3024         error = xfs_trans_commit(tp, 0);
3025         return error;
3026
3027 abort_error:
3028         xfs_trans_cancel(tp, XFS_TRANS_ABORT);
3029         return error;
3030 }
3031
3032 /*
3033  * Verify that once we've encountered something other than an EFI
3034  * in the AIL that there are no more EFIs in the AIL.
3035  */
3036 #if defined(DEBUG)
3037 STATIC void
3038 xlog_recover_check_ail(
3039         xfs_mount_t             *mp,
3040         xfs_log_item_t          *lip,
3041         int                     gen)
3042 {
3043         int                     orig_gen = gen;
3044
3045         do {
3046                 ASSERT(lip->li_type != XFS_LI_EFI);
3047                 lip = xfs_trans_next_ail(mp, lip, &gen, NULL);
3048                 /*
3049                  * The check will be bogus if we restart from the
3050                  * beginning of the AIL, so ASSERT that we don't.
3051                  * We never should since we're holding the AIL lock
3052                  * the entire time.
3053                  */
3054                 ASSERT(gen == orig_gen);
3055         } while (lip != NULL);
3056 }
3057 #endif  /* DEBUG */
3058
3059 /*
3060  * When this is called, all of the EFIs which did not have
3061  * corresponding EFDs should be in the AIL.  What we do now
3062  * is free the extents associated with each one.
3063  *
3064  * Since we process the EFIs in normal transactions, they
3065  * will be removed at some point after the commit.  This prevents
3066  * us from just walking down the list processing each one.
3067  * We'll use a flag in the EFI to skip those that we've already
3068  * processed and use the AIL iteration mechanism's generation
3069  * count to try to speed this up at least a bit.
3070  *
3071  * When we start, we know that the EFIs are the only things in
3072  * the AIL.  As we process them, however, other items are added
3073  * to the AIL.  Since everything added to the AIL must come after
3074  * everything already in the AIL, we stop processing as soon as
3075  * we see something other than an EFI in the AIL.
3076  */
3077 STATIC int
3078 xlog_recover_process_efis(
3079         xlog_t                  *log)
3080 {
3081         xfs_log_item_t          *lip;
3082         xfs_efi_log_item_t      *efip;
3083         int                     gen;
3084         xfs_mount_t             *mp;
3085         int                     error = 0;
3086
3087         mp = log->l_mp;
3088         spin_lock(&mp->m_ail_lock);
3089
3090         lip = xfs_trans_first_ail(mp, &gen);
3091         while (lip != NULL) {
3092                 /*
3093                  * We're done when we see something other than an EFI.
3094                  */
3095                 if (lip->li_type != XFS_LI_EFI) {
3096                         xlog_recover_check_ail(mp, lip, gen);
3097                         break;
3098                 }
3099
3100                 /*
3101                  * Skip EFIs that we've already processed.
3102                  */
3103                 efip = (xfs_efi_log_item_t *)lip;
3104                 if (efip->efi_flags & XFS_EFI_RECOVERED) {
3105                         lip = xfs_trans_next_ail(mp, lip, &gen, NULL);
3106                         continue;
3107                 }
3108
3109                 spin_unlock(&mp->m_ail_lock);
3110                 error = xlog_recover_process_efi(mp, efip);
3111                 if (error)
3112                         return error;
3113                 spin_lock(&mp->m_ail_lock);
3114                 lip = xfs_trans_next_ail(mp, lip, &gen, NULL);
3115         }
3116         spin_unlock(&mp->m_ail_lock);
3117         return error;
3118 }
3119
3120 /*
3121  * This routine performs a transaction to null out a bad inode pointer
3122  * in an agi unlinked inode hash bucket.
3123  */
3124 STATIC void
3125 xlog_recover_clear_agi_bucket(
3126         xfs_mount_t     *mp,
3127         xfs_agnumber_t  agno,
3128         int             bucket)
3129 {
3130         xfs_trans_t     *tp;
3131         xfs_agi_t       *agi;
3132         xfs_buf_t       *agibp;
3133         int             offset;
3134         int             error;
3135
3136         tp = xfs_trans_alloc(mp, XFS_TRANS_CLEAR_AGI_BUCKET);
3137         error = xfs_trans_reserve(tp, 0, XFS_CLEAR_AGI_BUCKET_LOG_RES(mp), 0, 0, 0);
3138         if (!error)
3139                 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
3140                                    XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
3141                                    XFS_FSS_TO_BB(mp, 1), 0, &agibp);
3142         if (error)
3143                 goto out_abort;
3144
3145         error = EINVAL;
3146         agi = XFS_BUF_TO_AGI(agibp);
3147         if (be32_to_cpu(agi->agi_magicnum) != XFS_AGI_MAGIC)
3148                 goto out_abort;
3149
3150         agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
3151         offset = offsetof(xfs_agi_t, agi_unlinked) +
3152                  (sizeof(xfs_agino_t) * bucket);
3153         xfs_trans_log_buf(tp, agibp, offset,
3154                           (offset + sizeof(xfs_agino_t) - 1));
3155
3156         error = xfs_trans_commit(tp, 0);
3157         if (error)
3158                 goto out_error;
3159         return;
3160
3161 out_abort:
3162         xfs_trans_cancel(tp, XFS_TRANS_ABORT);
3163 out_error:
3164         xfs_fs_cmn_err(CE_WARN, mp, "xlog_recover_clear_agi_bucket: "
3165                         "failed to clear agi %d. Continuing.", agno);
3166         return;
3167 }
3168
3169 /*
3170  * xlog_iunlink_recover
3171  *
3172  * This is called during recovery to process any inodes which
3173  * we unlinked but not freed when the system crashed.  These
3174  * inodes will be on the lists in the AGI blocks.  What we do
3175  * here is scan all the AGIs and fully truncate and free any
3176  * inodes found on the lists.  Each inode is removed from the
3177  * lists when it has been fully truncated and is freed.  The
3178  * freeing of the inode and its removal from the list must be
3179  * atomic.
3180  */
3181 void
3182 xlog_recover_process_iunlinks(
3183         xlog_t          *log)
3184 {
3185         xfs_mount_t     *mp;
3186         xfs_agnumber_t  agno;
3187         xfs_agi_t       *agi;
3188         xfs_buf_t       *agibp;
3189         xfs_buf_t       *ibp;
3190         xfs_dinode_t    *dip;
3191         xfs_inode_t     *ip;
3192         xfs_agino_t     agino;
3193         xfs_ino_t       ino;
3194         int             bucket;
3195         int             error;
3196         uint            mp_dmevmask;
3197
3198         mp = log->l_mp;
3199
3200         /*
3201          * Prevent any DMAPI event from being sent while in this function.
3202          */
3203         mp_dmevmask = mp->m_dmevmask;
3204         mp->m_dmevmask = 0;
3205
3206         for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
3207                 /*
3208                  * Find the agi for this ag.
3209                  */
3210                 agibp = xfs_buf_read(mp->m_ddev_targp,
3211                                 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
3212                                 XFS_FSS_TO_BB(mp, 1), 0);
3213                 if (XFS_BUF_ISERROR(agibp)) {
3214                         xfs_ioerror_alert("xlog_recover_process_iunlinks(#1)",
3215                                 log->l_mp, agibp,
3216                                 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)));
3217                 }
3218                 agi = XFS_BUF_TO_AGI(agibp);
3219                 ASSERT(XFS_AGI_MAGIC == be32_to_cpu(agi->agi_magicnum));
3220
3221                 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
3222
3223                         agino = be32_to_cpu(agi->agi_unlinked[bucket]);
3224                         while (agino != NULLAGINO) {
3225
3226                                 /*
3227                                  * Release the agi buffer so that it can
3228                                  * be acquired in the normal course of the
3229                                  * transaction to truncate and free the inode.
3230                                  */
3231                                 xfs_buf_relse(agibp);
3232
3233                                 ino = XFS_AGINO_TO_INO(mp, agno, agino);
3234                                 error = xfs_iget(mp, NULL, ino, 0, 0, &ip, 0);
3235                                 ASSERT(error || (ip != NULL));
3236
3237                                 if (!error) {
3238                                         /*
3239                                          * Get the on disk inode to find the
3240                                          * next inode in the bucket.
3241                                          */
3242                                         error = xfs_itobp(mp, NULL, ip, &dip,
3243                                                         &ibp, 0, 0,
3244                                                         XFS_BUF_LOCK);
3245                                         ASSERT(error || (dip != NULL));
3246                                 }
3247
3248                                 if (!error) {
3249                                         ASSERT(ip->i_d.di_nlink == 0);
3250
3251                                         /* setup for the next pass */
3252                                         agino = be32_to_cpu(
3253                                                         dip->di_next_unlinked);
3254                                         xfs_buf_relse(ibp);
3255                                         /*
3256                                          * Prevent any DMAPI event from
3257                                          * being sent when the
3258                                          * reference on the inode is
3259                                          * dropped.
3260                                          */
3261                                         ip->i_d.di_dmevmask = 0;
3262
3263                                         /*
3264                                          * If this is a new inode, handle
3265                                          * it specially.  Otherwise,
3266                                          * just drop our reference to the
3267                                          * inode.  If there are no
3268                                          * other references, this will
3269                                          * send the inode to
3270                                          * xfs_inactive() which will
3271                                          * truncate the file and free
3272                                          * the inode.
3273                                          */
3274                                         if (ip->i_d.di_mode == 0)
3275                                                 xfs_iput_new(ip, 0);
3276                                         else
3277                                                 IRELE(ip);
3278                                 } else {
3279                                         /*
3280                                          * We can't read in the inode
3281                                          * this bucket points to, or
3282                                          * this inode is messed up.  Just
3283                                          * ditch this bucket of inodes.  We
3284                                          * will lose some inodes and space,
3285                                          * but at least we won't hang.  Call
3286                                          * xlog_recover_clear_agi_bucket()
3287                                          * to perform a transaction to clear
3288                                          * the inode pointer in the bucket.
3289                                          */
3290                                         xlog_recover_clear_agi_bucket(mp, agno,
3291                                                         bucket);
3292
3293                                         agino = NULLAGINO;
3294                                 }
3295
3296                                 /*
3297                                  * Reacquire the agibuffer and continue around
3298                                  * the loop.
3299                                  */
3300                                 agibp = xfs_buf_read(mp->m_ddev_targp,
3301                                                 XFS_AG_DADDR(mp, agno,
3302                                                         XFS_AGI_DADDR(mp)),
3303                                                 XFS_FSS_TO_BB(mp, 1), 0);
3304                                 if (XFS_BUF_ISERROR(agibp)) {
3305                                         xfs_ioerror_alert(
3306                                 "xlog_recover_process_iunlinks(#2)",
3307                                                 log->l_mp, agibp,
3308                                                 XFS_AG_DADDR(mp, agno,
3309                                                         XFS_AGI_DADDR(mp)));
3310                                 }
3311                                 agi = XFS_BUF_TO_AGI(agibp);
3312                                 ASSERT(XFS_AGI_MAGIC == be32_to_cpu(
3313                                         agi->agi_magicnum));
3314                         }
3315                 }
3316
3317                 /*
3318                  * Release the buffer for the current agi so we can
3319                  * go on to the next one.
3320                  */
3321                 xfs_buf_relse(agibp);
3322         }
3323
3324         mp->m_dmevmask = mp_dmevmask;
3325 }
3326
3327
3328 #ifdef DEBUG
3329 STATIC void
3330 xlog_pack_data_checksum(
3331         xlog_t          *log,
3332         xlog_in_core_t  *iclog,
3333         int             size)
3334 {
3335         int             i;
3336         __be32          *up;
3337         uint            chksum = 0;
3338
3339         up = (__be32 *)iclog->ic_datap;
3340         /* divide length by 4 to get # words */
3341         for (i = 0; i < (size >> 2); i++) {
3342                 chksum ^= be32_to_cpu(*up);
3343                 up++;
3344         }
3345         iclog->ic_header.h_chksum = cpu_to_be32(chksum);
3346 }
3347 #else
3348 #define xlog_pack_data_checksum(log, iclog, size)
3349 #endif
3350
3351 /*
3352  * Stamp cycle number in every block
3353  */
3354 void
3355 xlog_pack_data(
3356         xlog_t                  *log,
3357         xlog_in_core_t          *iclog,
3358         int                     roundoff)
3359 {
3360         int                     i, j, k;
3361         int                     size = iclog->ic_offset + roundoff;
3362         __be32                  cycle_lsn;
3363         xfs_caddr_t             dp;
3364         xlog_in_core_2_t        *xhdr;
3365
3366         xlog_pack_data_checksum(log, iclog, size);
3367
3368         cycle_lsn = CYCLE_LSN_DISK(iclog->ic_header.h_lsn);
3369
3370         dp = iclog->ic_datap;
3371         for (i = 0; i < BTOBB(size) &&
3372                 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
3373                 iclog->ic_header.h_cycle_data[i] = *(__be32 *)dp;
3374                 *(__be32 *)dp = cycle_lsn;
3375                 dp += BBSIZE;
3376         }
3377
3378         if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3379                 xhdr = (xlog_in_core_2_t *)&iclog->ic_header;
3380                 for ( ; i < BTOBB(size); i++) {
3381                         j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3382                         k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3383                         xhdr[j].hic_xheader.xh_cycle_data[k] = *(__be32 *)dp;
3384                         *(__be32 *)dp = cycle_lsn;
3385                         dp += BBSIZE;
3386                 }
3387
3388                 for (i = 1; i < log->l_iclog_heads; i++) {
3389                         xhdr[i].hic_xheader.xh_cycle = cycle_lsn;
3390                 }
3391         }
3392 }
3393
3394 #if defined(DEBUG) && defined(XFS_LOUD_RECOVERY)
3395 STATIC void
3396 xlog_unpack_data_checksum(
3397         xlog_rec_header_t       *rhead,
3398         xfs_caddr_t             dp,
3399         xlog_t                  *log)
3400 {
3401         __be32                  *up = (__be32 *)dp;
3402         uint                    chksum = 0;
3403         int                     i;
3404
3405         /* divide length by 4 to get # words */
3406         for (i=0; i < be32_to_cpu(rhead->h_len) >> 2; i++) {
3407                 chksum ^= be32_to_cpu(*up);
3408                 up++;
3409         }
3410         if (chksum != be32_to_cpu(rhead->h_chksum)) {
3411             if (rhead->h_chksum ||
3412                 ((log->l_flags & XLOG_CHKSUM_MISMATCH) == 0)) {
3413                     cmn_err(CE_DEBUG,
3414                         "XFS: LogR chksum mismatch: was (0x%x) is (0x%x)\n",
3415                             be32_to_cpu(rhead->h_chksum), chksum);
3416                     cmn_err(CE_DEBUG,
3417 "XFS: Disregard message if filesystem was created with non-DEBUG kernel");
3418                     if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3419                             cmn_err(CE_DEBUG,
3420                                 "XFS: LogR this is a LogV2 filesystem\n");
3421                     }
3422                     log->l_flags |= XLOG_CHKSUM_MISMATCH;
3423             }
3424         }
3425 }
3426 #else
3427 #define xlog_unpack_data_checksum(rhead, dp, log)
3428 #endif
3429
3430 STATIC void
3431 xlog_unpack_data(
3432         xlog_rec_header_t       *rhead,
3433         xfs_caddr_t             dp,
3434         xlog_t                  *log)
3435 {
3436         int                     i, j, k;
3437         xlog_in_core_2_t        *xhdr;
3438
3439         for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
3440                   i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
3441                 *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
3442                 dp += BBSIZE;
3443         }
3444
3445         if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3446                 xhdr = (xlog_in_core_2_t *)rhead;
3447                 for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
3448                         j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3449                         k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3450                         *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
3451                         dp += BBSIZE;
3452                 }
3453         }
3454
3455         xlog_unpack_data_checksum(rhead, dp, log);
3456 }
3457
3458 STATIC int
3459 xlog_valid_rec_header(
3460         xlog_t                  *log,
3461         xlog_rec_header_t       *rhead,
3462         xfs_daddr_t             blkno)
3463 {
3464         int                     hlen;
3465
3466         if (unlikely(be32_to_cpu(rhead->h_magicno) != XLOG_HEADER_MAGIC_NUM)) {
3467                 XFS_ERROR_REPORT("xlog_valid_rec_header(1)",
3468                                 XFS_ERRLEVEL_LOW, log->l_mp);
3469                 return XFS_ERROR(EFSCORRUPTED);
3470         }
3471         if (unlikely(
3472             (!rhead->h_version ||
3473             (be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS))))) {
3474                 xlog_warn("XFS: %s: unrecognised log version (%d).",
3475                         __func__, be32_to_cpu(rhead->h_version));
3476                 return XFS_ERROR(EIO);
3477         }
3478
3479         /* LR body must have data or it wouldn't have been written */
3480         hlen = be32_to_cpu(rhead->h_len);
3481         if (unlikely( hlen <= 0 || hlen > INT_MAX )) {
3482                 XFS_ERROR_REPORT("xlog_valid_rec_header(2)",
3483                                 XFS_ERRLEVEL_LOW, log->l_mp);
3484                 return XFS_ERROR(EFSCORRUPTED);
3485         }
3486         if (unlikely( blkno > log->l_logBBsize || blkno > INT_MAX )) {
3487                 XFS_ERROR_REPORT("xlog_valid_rec_header(3)",
3488                                 XFS_ERRLEVEL_LOW, log->l_mp);
3489                 return XFS_ERROR(EFSCORRUPTED);
3490         }
3491         return 0;
3492 }
3493
3494 /*
3495  * Read the log from tail to head and process the log records found.
3496  * Handle the two cases where the tail and head are in the same cycle
3497  * and where the active portion of the log wraps around the end of
3498  * the physical log separately.  The pass parameter is passed through
3499  * to the routines called to process the data and is not looked at
3500  * here.
3501  */
3502 STATIC int
3503 xlog_do_recovery_pass(
3504         xlog_t                  *log,
3505         xfs_daddr_t             head_blk,
3506         xfs_daddr_t             tail_blk,
3507         int                     pass)
3508 {
3509         xlog_rec_header_t       *rhead;
3510         xfs_daddr_t             blk_no;
3511         xfs_caddr_t             bufaddr, offset;
3512         xfs_buf_t               *hbp, *dbp;
3513         int                     error = 0, h_size;
3514         int                     bblks, split_bblks;
3515         int                     hblks, split_hblks, wrapped_hblks;
3516         xlog_recover_t          *rhash[XLOG_RHASH_SIZE];
3517
3518         ASSERT(head_blk != tail_blk);
3519
3520         /*
3521          * Read the header of the tail block and get the iclog buffer size from
3522          * h_size.  Use this to tell how many sectors make up the log header.
3523          */
3524         if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3525                 /*
3526                  * When using variable length iclogs, read first sector of
3527                  * iclog header and extract the header size from it.  Get a
3528                  * new hbp that is the correct size.
3529                  */
3530                 hbp = xlog_get_bp(log, 1);
3531                 if (!hbp)
3532                         return ENOMEM;
3533                 if ((error = xlog_bread(log, tail_blk, 1, hbp)))
3534                         goto bread_err1;
3535                 offset = xlog_align(log, tail_blk, 1, hbp);
3536                 rhead = (xlog_rec_header_t *)offset;
3537                 error = xlog_valid_rec_header(log, rhead, tail_blk);
3538                 if (error)
3539                         goto bread_err1;
3540                 h_size = be32_to_cpu(rhead->h_size);
3541                 if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
3542                     (h_size > XLOG_HEADER_CYCLE_SIZE)) {
3543                         hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
3544                         if (h_size % XLOG_HEADER_CYCLE_SIZE)
3545                                 hblks++;
3546                         xlog_put_bp(hbp);
3547                         hbp = xlog_get_bp(log, hblks);
3548                 } else {
3549                         hblks = 1;
3550                 }
3551         } else {
3552                 ASSERT(log->l_sectbb_log == 0);
3553                 hblks = 1;
3554                 hbp = xlog_get_bp(log, 1);
3555                 h_size = XLOG_BIG_RECORD_BSIZE;
3556         }
3557
3558         if (!hbp)
3559                 return ENOMEM;
3560         dbp = xlog_get_bp(log, BTOBB(h_size));
3561         if (!dbp) {
3562                 xlog_put_bp(hbp);
3563                 return ENOMEM;
3564         }
3565
3566         memset(rhash, 0, sizeof(rhash));
3567         if (tail_blk <= head_blk) {
3568                 for (blk_no = tail_blk; blk_no < head_blk; ) {
3569                         if ((error = xlog_bread(log, blk_no, hblks, hbp)))
3570                                 goto bread_err2;
3571                         offset = xlog_align(log, blk_no, hblks, hbp);
3572                         rhead = (xlog_rec_header_t *)offset;
3573                         error = xlog_valid_rec_header(log, rhead, blk_no);
3574                         if (error)
3575                                 goto bread_err2;
3576
3577                         /* blocks in data section */
3578                         bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3579                         error = xlog_bread(log, blk_no + hblks, bblks, dbp);
3580                         if (error)
3581                                 goto bread_err2;
3582                         offset = xlog_align(log, blk_no + hblks, bblks, dbp);
3583                         xlog_unpack_data(rhead, offset, log);
3584                         if ((error = xlog_recover_process_data(log,
3585                                                 rhash, rhead, offset, pass)))
3586                                 goto bread_err2;
3587                         blk_no += bblks + hblks;
3588                 }
3589         } else {
3590                 /*
3591                  * Perform recovery around the end of the physical log.
3592                  * When the head is not on the same cycle number as the tail,
3593                  * we can't do a sequential recovery as above.
3594                  */
3595                 blk_no = tail_blk;
3596                 while (blk_no < log->l_logBBsize) {
3597                         /*
3598                          * Check for header wrapping around physical end-of-log
3599                          */
3600                         offset = NULL;
3601                         split_hblks = 0;
3602                         wrapped_hblks = 0;
3603                         if (blk_no + hblks <= log->l_logBBsize) {
3604                                 /* Read header in one read */
3605                                 error = xlog_bread(log, blk_no, hblks, hbp);
3606                                 if (error)
3607                                         goto bread_err2;
3608                                 offset = xlog_align(log, blk_no, hblks, hbp);
3609                         } else {
3610                                 /* This LR is split across physical log end */
3611                                 if (blk_no != log->l_logBBsize) {
3612                                         /* some data before physical log end */
3613                                         ASSERT(blk_no <= INT_MAX);
3614                                         split_hblks = log->l_logBBsize - (int)blk_no;
3615                                         ASSERT(split_hblks > 0);
3616                                         if ((error = xlog_bread(log, blk_no,
3617                                                         split_hblks, hbp)))
3618                                                 goto bread_err2;
3619                                         offset = xlog_align(log, blk_no,
3620                                                         split_hblks, hbp);
3621                                 }
3622                                 /*
3623                                  * Note: this black magic still works with
3624                                  * large sector sizes (non-512) only because:
3625                                  * - we increased the buffer size originally
3626                                  *   by 1 sector giving us enough extra space
3627                                  *   for the second read;
3628                                  * - the log start is guaranteed to be sector
3629                                  *   aligned;
3630                                  * - we read the log end (LR header start)
3631                                  *   _first_, then the log start (LR header end)
3632                                  *   - order is important.
3633                                  */
3634                                 wrapped_hblks = hblks - split_hblks;
3635                                 bufaddr = XFS_BUF_PTR(hbp);
3636                                 error = XFS_BUF_SET_PTR(hbp,
3637                                                 bufaddr + BBTOB(split_hblks),
3638                                                 BBTOB(hblks - split_hblks));
3639                                 if (!error)
3640                                         error = xlog_bread(log, 0,
3641                                                         wrapped_hblks, hbp);
3642                                 if (!error)
3643                                         error = XFS_BUF_SET_PTR(hbp, bufaddr,
3644                                                         BBTOB(hblks));
3645                                 if (error)
3646                                         goto bread_err2;
3647                                 if (!offset)
3648                                         offset = xlog_align(log, 0,
3649                                                         wrapped_hblks, hbp);
3650                         }
3651                         rhead = (xlog_rec_header_t *)offset;
3652                         error = xlog_valid_rec_header(log, rhead,
3653                                                 split_hblks ? blk_no : 0);
3654                         if (error)
3655                                 goto bread_err2;
3656
3657                         bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3658                         blk_no += hblks;
3659
3660                         /* Read in data for log record */
3661                         if (blk_no + bblks <= log->l_logBBsize) {
3662                                 error = xlog_bread(log, blk_no, bblks, dbp);
3663                                 if (error)
3664                                         goto bread_err2;
3665                                 offset = xlog_align(log, blk_no, bblks, dbp);
3666                         } else {
3667                                 /* This log record is split across the
3668                                  * physical end of log */
3669                                 offset = NULL;
3670                                 split_bblks = 0;
3671                                 if (blk_no != log->l_logBBsize) {
3672                                         /* some data is before the physical
3673                                          * end of log */
3674                                         ASSERT(!wrapped_hblks);
3675                                         ASSERT(blk_no <= INT_MAX);
3676                                         split_bblks =
3677                                                 log->l_logBBsize - (int)blk_no;
3678                                         ASSERT(split_bblks > 0);
3679                                         if ((error = xlog_bread(log, blk_no,
3680                                                         split_bblks, dbp)))
3681                                                 goto bread_err2;
3682                                         offset = xlog_align(log, blk_no,
3683                                                         split_bblks, dbp);
3684                                 }
3685                                 /*
3686                                  * Note: this black magic still works with
3687                                  * large sector sizes (non-512) only because:
3688                                  * - we increased the buffer size originally
3689                                  *   by 1 sector giving us enough extra space
3690                                  *   for the second read;
3691                                  * - the log start is guaranteed to be sector
3692                                  *   aligned;
3693                                  * - we read the log end (LR header start)
3694                                  *   _first_, then the log start (LR header end)
3695                                  *   - order is important.
3696                                  */
3697                                 bufaddr = XFS_BUF_PTR(dbp);
3698                                 error = XFS_BUF_SET_PTR(dbp,
3699                                                 bufaddr + BBTOB(split_bblks),
3700                                                 BBTOB(bblks - split_bblks));
3701                                 if (!error)
3702                                         error = xlog_bread(log, wrapped_hblks,
3703                                                         bblks - split_bblks,
3704                                                         dbp);
3705                                 if (!error)
3706                                         error = XFS_BUF_SET_PTR(dbp, bufaddr,
3707                                                         h_size);
3708                                 if (error)
3709                                         goto bread_err2;
3710                                 if (!offset)
3711                                         offset = xlog_align(log, wrapped_hblks,
3712                                                 bblks - split_bblks, dbp);
3713                         }
3714                         xlog_unpack_data(rhead, offset, log);
3715                         if ((error = xlog_recover_process_data(log, rhash,
3716                                                         rhead, offset, pass)))
3717                                 goto bread_err2;
3718                         blk_no += bblks;
3719                 }
3720
3721                 ASSERT(blk_no >= log->l_logBBsize);
3722                 blk_no -= log->l_logBBsize;
3723
3724                 /* read first part of physical log */
3725                 while (blk_no < head_blk) {
3726                         if ((error = xlog_bread(log, blk_no, hblks, hbp)))
3727                                 goto bread_err2;
3728                         offset = xlog_align(log, blk_no, hblks, hbp);
3729                         rhead = (xlog_rec_header_t *)offset;
3730                         error = xlog_valid_rec_header(log, rhead, blk_no);
3731                         if (error)
3732                                 goto bread_err2;
3733                         bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3734                         if ((error = xlog_bread(log, blk_no+hblks, bblks, dbp)))
3735                                 goto bread_err2;
3736                         offset = xlog_align(log, blk_no+hblks, bblks, dbp);
3737                         xlog_unpack_data(rhead, offset, log);
3738                         if ((error = xlog_recover_process_data(log, rhash,
3739                                                         rhead, offset, pass)))
3740                                 goto bread_err2;
3741                         blk_no += bblks + hblks;
3742                 }
3743         }
3744
3745  bread_err2:
3746         xlog_put_bp(dbp);
3747  bread_err1:
3748         xlog_put_bp(hbp);
3749         return error;
3750 }
3751
3752 /*
3753  * Do the recovery of the log.  We actually do this in two phases.
3754  * The two passes are necessary in order to implement the function
3755  * of cancelling a record written into the log.  The first pass
3756  * determines those things which have been cancelled, and the
3757  * second pass replays log items normally except for those which
3758  * have been cancelled.  The handling of the replay and cancellations
3759  * takes place in the log item type specific routines.
3760  *
3761  * The table of items which have cancel records in the log is allocated
3762  * and freed at this level, since only here do we know when all of
3763  * the log recovery has been completed.
3764  */
3765 STATIC int
3766 xlog_do_log_recovery(
3767         xlog_t          *log,
3768         xfs_daddr_t     head_blk,
3769         xfs_daddr_t     tail_blk)
3770 {
3771         int             error;
3772
3773         ASSERT(head_blk != tail_blk);
3774
3775         /*
3776          * First do a pass to find all of the cancelled buf log items.
3777          * Store them in the buf_cancel_table for use in the second pass.
3778          */
3779         log->l_buf_cancel_table =
3780                 (xfs_buf_cancel_t **)kmem_zalloc(XLOG_BC_TABLE_SIZE *
3781                                                  sizeof(xfs_buf_cancel_t*),
3782                                                  KM_SLEEP);
3783         error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3784                                       XLOG_RECOVER_PASS1);
3785         if (error != 0) {
3786                 kmem_free(log->l_buf_cancel_table);
3787                 log->l_buf_cancel_table = NULL;
3788                 return error;
3789         }
3790         /*
3791          * Then do a second pass to actually recover the items in the log.
3792          * When it is complete free the table of buf cancel items.
3793          */
3794         error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3795                                       XLOG_RECOVER_PASS2);
3796 #ifdef DEBUG
3797         if (!error) {
3798                 int     i;
3799
3800                 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
3801                         ASSERT(log->l_buf_cancel_table[i] == NULL);
3802         }
3803 #endif  /* DEBUG */
3804
3805         kmem_free(log->l_buf_cancel_table);
3806         log->l_buf_cancel_table = NULL;
3807
3808         return error;
3809 }
3810
3811 /*
3812  * Do the actual recovery
3813  */
3814 STATIC int
3815 xlog_do_recover(
3816         xlog_t          *log,
3817         xfs_daddr_t     head_blk,
3818         xfs_daddr_t     tail_blk)
3819 {
3820         int             error;
3821         xfs_buf_t       *bp;
3822         xfs_sb_t        *sbp;
3823
3824         /*
3825          * First replay the images in the log.
3826          */
3827         error = xlog_do_log_recovery(log, head_blk, tail_blk);
3828         if (error) {
3829                 return error;
3830         }
3831
3832         XFS_bflush(log->l_mp->m_ddev_targp);
3833
3834         /*
3835          * If IO errors happened during recovery, bail out.
3836          */
3837         if (XFS_FORCED_SHUTDOWN(log->l_mp)) {
3838                 return (EIO);
3839         }
3840
3841         /*
3842          * We now update the tail_lsn since much of the recovery has completed
3843          * and there may be space available to use.  If there were no extent
3844          * or iunlinks, we can free up the entire log and set the tail_lsn to
3845          * be the last_sync_lsn.  This was set in xlog_find_tail to be the
3846          * lsn of the last known good LR on disk.  If there are extent frees
3847          * or iunlinks they will have some entries in the AIL; so we look at
3848          * the AIL to determine how to set the tail_lsn.
3849          */
3850         xlog_assign_tail_lsn(log->l_mp);
3851
3852         /*
3853          * Now that we've finished replaying all buffer and inode
3854          * updates, re-read in the superblock.
3855          */
3856         bp = xfs_getsb(log->l_mp, 0);
3857         XFS_BUF_UNDONE(bp);
3858         ASSERT(!(XFS_BUF_ISWRITE(bp)));
3859         ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));
3860         XFS_BUF_READ(bp);
3861         XFS_BUF_UNASYNC(bp);
3862         xfsbdstrat(log->l_mp, bp);
3863         error = xfs_iowait(bp);
3864         if (error) {
3865                 xfs_ioerror_alert("xlog_do_recover",
3866                                   log->l_mp, bp, XFS_BUF_ADDR(bp));
3867                 ASSERT(0);
3868                 xfs_buf_relse(bp);
3869                 return error;
3870         }
3871
3872         /* Convert superblock from on-disk format */
3873         sbp = &log->l_mp->m_sb;
3874         xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
3875         ASSERT(sbp->sb_magicnum == XFS_SB_MAGIC);
3876         ASSERT(xfs_sb_good_version(sbp));
3877         xfs_buf_relse(bp);
3878
3879         /* We've re-read the superblock so re-initialize per-cpu counters */
3880         xfs_icsb_reinit_counters(log->l_mp);
3881
3882         xlog_recover_check_summary(log);
3883
3884         /* Normal transactions can now occur */
3885         log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
3886         return 0;
3887 }
3888
3889 /*
3890  * Perform recovery and re-initialize some log variables in xlog_find_tail.
3891  *
3892  * Return error or zero.
3893  */
3894 int
3895 xlog_recover(
3896         xlog_t          *log)
3897 {
3898         xfs_daddr_t     head_blk, tail_blk;
3899         int             error;
3900
3901         /* find the tail of the log */
3902         if ((error = xlog_find_tail(log, &head_blk, &tail_blk)))
3903                 return error;
3904
3905         if (tail_blk != head_blk) {
3906                 /* There used to be a comment here:
3907                  *
3908                  * disallow recovery on read-only mounts.  note -- mount
3909                  * checks for ENOSPC and turns it into an intelligent
3910                  * error message.
3911                  * ...but this is no longer true.  Now, unless you specify
3912                  * NORECOVERY (in which case this function would never be
3913                  * called), we just go ahead and recover.  We do this all
3914                  * under the vfs layer, so we can get away with it unless
3915                  * the device itself is read-only, in which case we fail.
3916                  */
3917                 if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
3918                         return error;
3919                 }
3920
3921                 cmn_err(CE_NOTE,
3922                         "Starting XFS recovery on filesystem: %s (logdev: %s)",
3923                         log->l_mp->m_fsname, log->l_mp->m_logname ?
3924                         log->l_mp->m_logname : "internal");
3925
3926                 error = xlog_do_recover(log, head_blk, tail_blk);
3927                 log->l_flags |= XLOG_RECOVERY_NEEDED;
3928         }
3929         return error;
3930 }
3931
3932 /*
3933  * In the first part of recovery we replay inodes and buffers and build
3934  * up the list of extent free items which need to be processed.  Here
3935  * we process the extent free items and clean up the on disk unlinked
3936  * inode lists.  This is separated from the first part of recovery so
3937  * that the root and real-time bitmap inodes can be read in from disk in
3938  * between the two stages.  This is necessary so that we can free space
3939  * in the real-time portion of the file system.
3940  */
3941 int
3942 xlog_recover_finish(
3943         xlog_t          *log)
3944 {
3945         /*
3946          * Now we're ready to do the transactions needed for the
3947          * rest of recovery.  Start with completing all the extent
3948          * free intent records and then process the unlinked inode
3949          * lists.  At this point, we essentially run in normal mode
3950          * except that we're still performing recovery actions
3951          * rather than accepting new requests.
3952          */
3953         if (log->l_flags & XLOG_RECOVERY_NEEDED) {
3954                 int     error;
3955                 error = xlog_recover_process_efis(log);
3956                 if (error) {
3957                         cmn_err(CE_ALERT,
3958                                 "Failed to recover EFIs on filesystem: %s",
3959                                 log->l_mp->m_fsname);
3960                         return error;
3961                 }
3962                 /*
3963                  * Sync the log to get all the EFIs out of the AIL.
3964                  * This isn't absolutely necessary, but it helps in
3965                  * case the unlink transactions would have problems
3966                  * pushing the EFIs out of the way.
3967                  */
3968                 xfs_log_force(log->l_mp, (xfs_lsn_t)0,
3969                               (XFS_LOG_FORCE | XFS_LOG_SYNC));
3970
3971                 xlog_recover_process_iunlinks(log);
3972
3973                 xlog_recover_check_summary(log);
3974
3975                 cmn_err(CE_NOTE,
3976                         "Ending XFS recovery on filesystem: %s (logdev: %s)",
3977                         log->l_mp->m_fsname, log->l_mp->m_logname ?
3978                         log->l_mp->m_logname : "internal");
3979                 log->l_flags &= ~XLOG_RECOVERY_NEEDED;
3980         } else {
3981                 cmn_err(CE_DEBUG,
3982                         "!Ending clean XFS mount for filesystem: %s\n",
3983                         log->l_mp->m_fsname);
3984         }
3985         return 0;
3986 }
3987
3988
3989 #if defined(DEBUG)
3990 /*
3991  * Read all of the agf and agi counters and check that they
3992  * are consistent with the superblock counters.
3993  */
3994 void
3995 xlog_recover_check_summary(
3996         xlog_t          *log)
3997 {
3998         xfs_mount_t     *mp;
3999         xfs_agf_t       *agfp;
4000         xfs_agi_t       *agip;
4001         xfs_buf_t       *agfbp;
4002         xfs_buf_t       *agibp;
4003         xfs_daddr_t     agfdaddr;
4004         xfs_daddr_t     agidaddr;
4005         xfs_buf_t       *sbbp;
4006 #ifdef XFS_LOUD_RECOVERY
4007         xfs_sb_t        *sbp;
4008 #endif
4009         xfs_agnumber_t  agno;
4010         __uint64_t      freeblks;
4011         __uint64_t      itotal;
4012         __uint64_t      ifree;
4013
4014         mp = log->l_mp;
4015
4016         freeblks = 0LL;
4017         itotal = 0LL;
4018         ifree = 0LL;
4019         for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
4020                 agfdaddr = XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp));
4021                 agfbp = xfs_buf_read(mp->m_ddev_targp, agfdaddr,
4022                                 XFS_FSS_TO_BB(mp, 1), 0);
4023                 if (XFS_BUF_ISERROR(agfbp)) {
4024                         xfs_ioerror_alert("xlog_recover_check_summary(agf)",
4025                                                 mp, agfbp, agfdaddr);
4026                 }
4027                 agfp = XFS_BUF_TO_AGF(agfbp);
4028                 ASSERT(XFS_AGF_MAGIC == be32_to_cpu(agfp->agf_magicnum));
4029                 ASSERT(XFS_AGF_GOOD_VERSION(be32_to_cpu(agfp->agf_versionnum)));
4030                 ASSERT(be32_to_cpu(agfp->agf_seqno) == agno);
4031
4032                 freeblks += be32_to_cpu(agfp->agf_freeblks) +
4033                             be32_to_cpu(agfp->agf_flcount);
4034                 xfs_buf_relse(agfbp);
4035
4036                 agidaddr = XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp));
4037                 agibp = xfs_buf_read(mp->m_ddev_targp, agidaddr,
4038                                 XFS_FSS_TO_BB(mp, 1), 0);
4039                 if (XFS_BUF_ISERROR(agibp)) {
4040                         xfs_ioerror_alert("xlog_recover_check_summary(agi)",
4041                                           mp, agibp, agidaddr);
4042                 }
4043                 agip = XFS_BUF_TO_AGI(agibp);
4044                 ASSERT(XFS_AGI_MAGIC == be32_to_cpu(agip->agi_magicnum));
4045                 ASSERT(XFS_AGI_GOOD_VERSION(be32_to_cpu(agip->agi_versionnum)));
4046                 ASSERT(be32_to_cpu(agip->agi_seqno) == agno);
4047
4048                 itotal += be32_to_cpu(agip->agi_count);
4049                 ifree += be32_to_cpu(agip->agi_freecount);
4050                 xfs_buf_relse(agibp);
4051         }
4052
4053         sbbp = xfs_getsb(mp, 0);
4054 #ifdef XFS_LOUD_RECOVERY
4055         sbp = &mp->m_sb;
4056         xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(sbbp));
4057         cmn_err(CE_NOTE,
4058                 "xlog_recover_check_summary: sb_icount %Lu itotal %Lu",
4059                 sbp->sb_icount, itotal);
4060         cmn_err(CE_NOTE,
4061                 "xlog_recover_check_summary: sb_ifree %Lu itotal %Lu",
4062                 sbp->sb_ifree, ifree);
4063         cmn_err(CE_NOTE,
4064                 "xlog_recover_check_summary: sb_fdblocks %Lu freeblks %Lu",
4065                 sbp->sb_fdblocks, freeblks);
4066 #if 0
4067         /*
4068          * This is turned off until I account for the allocation
4069          * btree blocks which live in free space.
4070          */
4071         ASSERT(sbp->sb_icount == itotal);
4072         ASSERT(sbp->sb_ifree == ifree);
4073         ASSERT(sbp->sb_fdblocks == freeblks);
4074 #endif
4075 #endif
4076         xfs_buf_relse(sbbp);
4077 }
4078 #endif /* DEBUG */