2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
13 #include <afsconfig.h>
14 #include "afs/param.h"
17 #include "afs/sysincludes.h" /*Standard vendor system headers */
18 #include "afsincludes.h" /*AFS-based standard headers */
19 #include "afs/afs_stats.h" /* statistics */
20 #include "afs/afs_cbqueue.h"
21 #include "afs/afs_osidnlc.h"
23 /* Forward declarations. */
24 static void afs_GetDownD(int anumber, int *aneedSpace, afs_int32 buckethint);
25 static void afs_FreeDiscardedDCache(void);
26 static void afs_DiscardDCache(struct dcache *);
27 static void afs_FreeDCache(struct dcache *);
29 static afs_int32 afs_DCGetBucket(struct vcache *);
30 static void afs_DCAdjustSize(struct dcache *, afs_int32, afs_int32);
31 static void afs_DCMoveBucket(struct dcache *, afs_int32, afs_int32);
32 static void afs_DCSizeInit(void);
33 static afs_int32 afs_DCWhichBucket(afs_int32, afs_int32);
36 * --------------------- Exported definitions ---------------------
39 afs_int32 afs_blocksUsed_0; /*!< 1K blocks in cache - in theory is zero */
40 afs_int32 afs_blocksUsed_1; /*!< 1K blocks in cache */
41 afs_int32 afs_blocksUsed_2; /*!< 1K blocks in cache */
42 afs_int32 afs_pct1 = -1;
43 afs_int32 afs_pct2 = -1;
44 afs_uint32 afs_tpct1 = 0;
45 afs_uint32 afs_tpct2 = 0;
46 afs_uint32 splitdcache = 0;
48 afs_lock_t afs_xdcache; /*!< Lock: alloc new disk cache entries */
49 afs_int32 afs_freeDCList; /*!< Free list for disk cache entries */
50 afs_int32 afs_freeDCCount; /*!< Count of elts in freeDCList */
51 afs_int32 afs_discardDCList; /*!< Discarded disk cache entries */
52 afs_int32 afs_discardDCCount; /*!< Count of elts in discardDCList */
53 struct dcache *afs_freeDSList; /*!< Free list for disk slots */
54 struct dcache *afs_Initial_freeDSList; /*!< Initial list for above */
55 afs_dcache_id_t cacheInode; /*!< Inode for CacheItems file */
56 struct osi_file *afs_cacheInodep = 0; /*!< file for CacheItems inode */
57 struct afs_q afs_DLRU; /*!< dcache LRU */
58 afs_int32 afs_dhashsize = 1024;
59 afs_int32 *afs_dvhashTbl; /*!< Data cache hash table: hashed by FID + chunk number. */
60 afs_int32 *afs_dchashTbl; /*!< Data cache hash table: hashed by FID. */
61 afs_int32 *afs_dvnextTbl; /*!< Dcache hash table links */
62 afs_int32 *afs_dcnextTbl; /*!< Dcache hash table links */
63 struct dcache **afs_indexTable; /*!< Pointers to dcache entries */
64 afs_hyper_t *afs_indexTimes; /*!< Dcache entry Access times */
65 afs_int32 *afs_indexUnique; /*!< dcache entry Fid.Unique */
66 unsigned char *afs_indexFlags; /*!< (only one) Is there data there? */
67 afs_hyper_t afs_indexCounter; /*!< Fake time for marking index
69 afs_int32 afs_cacheFiles = 0; /*!< Size of afs_indexTable */
70 afs_int32 afs_cacheBlocks; /*!< 1K blocks in cache */
71 afs_int32 afs_cacheStats; /*!< Stat entries in cache */
72 afs_int32 afs_blocksUsed; /*!< Number of blocks in use */
73 afs_int32 afs_blocksDiscarded; /*!<Blocks freed but not truncated */
74 afs_int32 afs_fsfragsize = 1023; /*!< Underlying Filesystem minimum unit
75 *of disk allocation usually 1K
76 *this value is (truefrag -1 ) to
77 *save a bunch of subtracts... */
78 #ifdef AFS_64BIT_CLIENT
79 #ifdef AFS_VM_RDWR_ENV
80 afs_size_t afs_vmMappingEnd; /* !< For large files (>= 2GB) the VM
81 * mapping an 32bit addressing machines
82 * can only be used below the 2 GB
83 * line. From this point upwards we
84 * must do direct I/O into the cache
85 * files. The value should be on a
87 #endif /* AFS_VM_RDWR_ENV */
88 #endif /* AFS_64BIT_CLIENT */
90 /* The following is used to ensure that new dcache's aren't obtained when
91 * the cache is nearly full.
93 int afs_WaitForCacheDrain = 0;
94 int afs_TruncateDaemonRunning = 0;
95 int afs_CacheTooFull = 0;
97 afs_int32 afs_dcentries; /*!< In-memory dcache entries */
100 int dcacheDisabled = 0;
102 static int afs_UFSCacheFetchProc(struct rx_call *, struct osi_file *,
103 afs_size_t, struct dcache *,
104 struct vcache *, afs_size_t *,
105 afs_size_t *, afs_int32);
107 static int afs_UFSCacheStoreProc(struct rx_call *, struct osi_file *,
108 afs_int32, struct vcache *,
112 struct afs_cacheOps afs_UfsCacheOps = {
120 afs_UFSCacheFetchProc,
121 afs_UFSCacheStoreProc,
127 struct afs_cacheOps afs_MemCacheOps = {
129 afs_MemCacheTruncate,
135 afs_MemCacheFetchProc,
136 afs_MemCacheStoreProc,
142 int cacheDiskType; /*Type of backing disk for cache */
143 struct afs_cacheOps *afs_cacheType;
146 * Where is this vcache's entry associated dcache located/
147 * \param avc The vcache entry.
148 * \return Bucket index:
153 afs_DCGetBucket(struct vcache *avc)
158 /* This should be replaced with some sort of user configurable function */
159 if (avc->f.states & CRO) {
161 } else if (avc->f.states & CBackup) {
171 * Readjust a dcache's size.
173 * \param adc The dcache to be adjusted.
174 * \param oldSize Old size for the dcache.
175 * \param newSize The new size to be adjusted to.
179 afs_DCAdjustSize(struct dcache *adc, afs_int32 oldSize, afs_int32 newSize)
181 afs_int32 adjustSize = newSize - oldSize;
189 afs_blocksUsed_0 += adjustSize;
190 afs_stats_cmperf.cacheBucket0_Discarded += oldSize;
193 afs_blocksUsed_1 += adjustSize;
194 afs_stats_cmperf.cacheBucket1_Discarded += oldSize;
197 afs_blocksUsed_2 += adjustSize;
198 afs_stats_cmperf.cacheBucket2_Discarded += oldSize;
206 * Move a dcache from one bucket to another.
208 * \param adc Operate on this dcache.
209 * \param size Size in bucket (?).
210 * \param newBucket Destination bucket.
214 afs_DCMoveBucket(struct dcache *adc, afs_int32 size, afs_int32 newBucket)
219 /* Substract size from old bucket. */
223 afs_blocksUsed_0 -= size;
226 afs_blocksUsed_1 -= size;
229 afs_blocksUsed_2 -= size;
233 /* Set new bucket and increase destination bucket size. */
234 adc->bucket = newBucket;
239 afs_blocksUsed_0 += size;
242 afs_blocksUsed_1 += size;
245 afs_blocksUsed_2 += size;
253 * Init split caches size.
258 afs_blocksUsed_0 = afs_blocksUsed_1 = afs_blocksUsed_2 = 0;
267 afs_DCWhichBucket(afs_int32 phase, afs_int32 bucket)
272 afs_pct1 = afs_blocksUsed_1 / (afs_cacheBlocks / 100);
273 afs_pct2 = afs_blocksUsed_2 / (afs_cacheBlocks / 100);
275 /* Short cut: if we don't know about it, try to kill it */
276 if (phase < 2 && afs_blocksUsed_0)
279 if (afs_pct1 > afs_tpct1)
281 if (afs_pct2 > afs_tpct2)
283 return 0; /* unlikely */
288 * Warn about failing to store a file.
290 * \param acode Associated error code.
291 * \param avolume Volume involved.
292 * \param aflags How to handle the output:
293 * aflags & 1: Print out on console
294 * aflags & 2: Print out on controlling tty
296 * \note Environment: Call this from close call when vnodeops is RCS unlocked.
300 afs_StoreWarn(register afs_int32 acode, afs_int32 avolume,
301 register afs_int32 aflags)
303 static char problem_fmt[] =
304 "afs: failed to store file in volume %d (%s)\n";
305 static char problem_fmt_w_error[] =
306 "afs: failed to store file in volume %d (error %d)\n";
307 static char netproblems[] = "network problems";
308 static char partfull[] = "partition full";
309 static char overquota[] = "over quota";
311 AFS_STATCNT(afs_StoreWarn);
317 afs_warn(problem_fmt, avolume, netproblems);
319 afs_warnuser(problem_fmt, avolume, netproblems);
320 } else if (acode == ENOSPC) {
325 afs_warn(problem_fmt, avolume, partfull);
327 afs_warnuser(problem_fmt, avolume, partfull);
330 /* EDQUOT doesn't exist on solaris and won't be sent by the server.
331 * Instead ENOSPC will be sent...
333 if (acode == EDQUOT) {
338 afs_warn(problem_fmt, avolume, overquota);
340 afs_warnuser(problem_fmt, avolume, overquota);
348 afs_warn(problem_fmt_w_error, avolume, acode);
350 afs_warnuser(problem_fmt_w_error, avolume, acode);
355 * Try waking up truncation daemon, if it's worth it.
358 afs_MaybeWakeupTruncateDaemon(void)
360 if (!afs_CacheTooFull && afs_CacheIsTooFull()) {
361 afs_CacheTooFull = 1;
362 if (!afs_TruncateDaemonRunning)
363 afs_osi_Wakeup((int *)afs_CacheTruncateDaemon);
364 } else if (!afs_TruncateDaemonRunning
365 && afs_blocksDiscarded > CM_MAXDISCARDEDCHUNKS) {
366 afs_osi_Wakeup((int *)afs_CacheTruncateDaemon);
373 * Keep statistics on run time for afs_CacheTruncateDaemon. This is a
374 * struct so we need only export one symbol for AIX.
376 static struct CTD_stats {
377 osi_timeval_t CTD_beforeSleep;
378 osi_timeval_t CTD_afterSleep;
379 osi_timeval_t CTD_sleepTime;
380 osi_timeval_t CTD_runTime;
384 u_int afs_min_cache = 0;
387 * Keeps the cache clean and free by truncating uneeded files, when used.
392 afs_CacheTruncateDaemon(void)
394 osi_timeval_t CTD_tmpTime;
398 PERCENT((100 - CM_DCACHECOUNTFREEPCT + CM_DCACHEEXTRAPCT), afs_cacheFiles);
400 (((10 * AFS_CHUNKSIZE(0)) + afs_fsfragsize) & ~afs_fsfragsize) >> 10;
402 osi_GetuTime(&CTD_stats.CTD_afterSleep);
403 afs_TruncateDaemonRunning = 1;
405 cb_lowat = PERCENT((CM_DCACHESPACEFREEPCT - CM_DCACHEEXTRAPCT), afs_cacheBlocks);
406 MObtainWriteLock(&afs_xdcache, 266);
407 if (afs_CacheTooFull) {
408 int space_needed, slots_needed;
409 /* if we get woken up, we should try to clean something out */
410 for (counter = 0; counter < 10; counter++) {
412 afs_blocksUsed - afs_blocksDiscarded - cb_lowat;
414 dc_hiwat - afs_freeDCCount - afs_discardDCCount;
415 afs_GetDownD(slots_needed, &space_needed, 0);
416 if ((space_needed <= 0) && (slots_needed <= 0)) {
419 if (afs_termState == AFSOP_STOP_TRUNCDAEMON)
422 if (!afs_CacheIsTooFull())
423 afs_CacheTooFull = 0;
424 } /* end of cache cleanup */
425 MReleaseWriteLock(&afs_xdcache);
428 * This is a defensive check to try to avoid starving threads
429 * that may need the global lock so thay can help free some
430 * cache space. If this thread won't be sleeping or truncating
431 * any cache files then give up the global lock so other
432 * threads get a chance to run.
434 if ((afs_termState != AFSOP_STOP_TRUNCDAEMON) && afs_CacheTooFull
435 && (!afs_blocksDiscarded || afs_WaitForCacheDrain)) {
436 afs_osi_Wait(100, 0, 0); /* 100 milliseconds */
440 * This is where we free the discarded cache elements.
442 while (afs_blocksDiscarded && !afs_WaitForCacheDrain
443 && (afs_termState != AFSOP_STOP_TRUNCDAEMON)) {
444 afs_FreeDiscardedDCache();
447 /* See if we need to continue to run. Someone may have
448 * signalled us while we were executing.
450 if (!afs_WaitForCacheDrain && !afs_CacheTooFull
451 && (afs_termState != AFSOP_STOP_TRUNCDAEMON)) {
452 /* Collect statistics on truncate daemon. */
453 CTD_stats.CTD_nSleeps++;
454 osi_GetuTime(&CTD_stats.CTD_beforeSleep);
455 afs_stats_GetDiff(CTD_tmpTime, CTD_stats.CTD_afterSleep,
456 CTD_stats.CTD_beforeSleep);
457 afs_stats_AddTo(CTD_stats.CTD_runTime, CTD_tmpTime);
459 afs_TruncateDaemonRunning = 0;
460 afs_osi_Sleep((int *)afs_CacheTruncateDaemon);
461 afs_TruncateDaemonRunning = 1;
463 osi_GetuTime(&CTD_stats.CTD_afterSleep);
464 afs_stats_GetDiff(CTD_tmpTime, CTD_stats.CTD_beforeSleep,
465 CTD_stats.CTD_afterSleep);
466 afs_stats_AddTo(CTD_stats.CTD_sleepTime, CTD_tmpTime);
468 if (afs_termState == AFSOP_STOP_TRUNCDAEMON) {
470 afs_termState = AFSOP_STOP_AFSDB;
472 afs_termState = AFSOP_STOP_RXEVENT;
474 afs_osi_Wakeup(&afs_termState);
482 * Make adjustment for the new size in the disk cache entry
484 * \note Major Assumptions Here:
485 * Assumes that frag size is an integral power of two, less one,
486 * and that this is a two's complement machine. I don't
487 * know of any filesystems which violate this assumption...
489 * \param adc Ptr to dcache entry.
490 * \param anewsize New size desired.
495 afs_AdjustSize(register struct dcache *adc, register afs_int32 newSize)
497 register afs_int32 oldSize;
499 AFS_STATCNT(afs_AdjustSize);
501 adc->dflags |= DFEntryMod;
502 oldSize = ((adc->f.chunkBytes + afs_fsfragsize) ^ afs_fsfragsize) >> 10; /* round up */
503 adc->f.chunkBytes = newSize;
506 newSize = ((newSize + afs_fsfragsize) ^ afs_fsfragsize) >> 10; /* round up */
507 afs_DCAdjustSize(adc, oldSize, newSize);
508 if ((newSize > oldSize) && !AFS_IS_DISCONNECTED) {
510 /* We're growing the file, wakeup the daemon */
511 afs_MaybeWakeupTruncateDaemon();
513 afs_blocksUsed += (newSize - oldSize);
514 afs_stats_cmperf.cacheBlocksInUse = afs_blocksUsed; /* XXX */
519 * This routine is responsible for moving at least one entry (but up
520 * to some number of them) from the LRU queue to the free queue.
522 * \param anumber Number of entries that should ideally be moved.
523 * \param aneedSpace How much space we need (1K blocks);
526 * The anumber parameter is just a hint; at least one entry MUST be
527 * moved, or we'll panic. We must be called with afs_xdcache
528 * write-locked. We should try to satisfy both anumber and aneedspace,
529 * whichever is more demanding - need to do several things:
530 * 1. only grab up to anumber victims if aneedSpace <= 0, not
531 * the whole set of MAXATONCE.
532 * 2. dynamically choose MAXATONCE to reflect severity of
533 * demand: something like (*aneedSpace >> (logChunk - 9))
535 * \note N.B. if we're called with aneedSpace <= 0 and anumber > 0, that
536 * indicates that the cache is not properly configured/tuned or
537 * something. We should be able to automatically correct that problem.
540 #define MAXATONCE 16 /* max we can obtain at once */
542 afs_GetDownD(int anumber, int *aneedSpace, afs_int32 buckethint)
546 struct VenusFid *afid;
550 register struct vcache *tvc;
551 afs_uint32 victims[MAXATONCE];
552 struct dcache *victimDCs[MAXATONCE];
553 afs_hyper_t victimTimes[MAXATONCE]; /* youngest (largest LRU time) first */
554 afs_uint32 victimPtr; /* next free item in victim arrays */
555 afs_hyper_t maxVictimTime; /* youngest (largest LRU time) victim */
556 afs_uint32 maxVictimPtr; /* where it is */
559 #if defined(AFS_FBSD80_ENV) && !defined(UKERNEL)
563 #if defined(AFS_FBSD80_ENV) && !defined(UKERNEL)
564 vfslocked = VFS_LOCK_GIANT(afs_globalVFS);
567 AFS_STATCNT(afs_GetDownD);
569 if (CheckLock(&afs_xdcache) != -1)
570 osi_Panic("getdownd nolock");
571 /* decrement anumber first for all dudes in free list */
572 /* SHOULD always decrement anumber first, even if aneedSpace >0,
573 * because we should try to free space even if anumber <=0 */
574 if (!aneedSpace || *aneedSpace <= 0) {
575 anumber -= afs_freeDCCount;
577 #if defined(AFS_FBSD80_ENV) && !defined(UKERNEL)
578 VFS_UNLOCK_GIANT(vfslocked);
580 return; /* enough already free */
584 /* bounds check parameter */
585 if (anumber > MAXATONCE)
586 anumber = MAXATONCE; /* all we can do */
588 /* rewrite so phases include a better eligiblity for gc test*/
590 * The phase variable manages reclaims. Set to 0, the first pass,
591 * we don't reclaim active entries, or other than target bucket.
592 * Set to 1, we reclaim even active ones in target bucket.
593 * Set to 2, we reclaim any inactive one.
594 * Set to 3, we reclaim even active ones.
602 for (i = 0; i < afs_cacheFiles; i++)
603 /* turn off all flags */
604 afs_indexFlags[i] &= ~IFFlag;
606 while (anumber > 0 || (aneedSpace && *aneedSpace > 0)) {
607 /* find oldest entries for reclamation */
608 maxVictimPtr = victimPtr = 0;
609 hzero(maxVictimTime);
610 curbucket = afs_DCWhichBucket(phase, buckethint);
611 /* select victims from access time array */
612 for (i = 0; i < afs_cacheFiles; i++) {
613 if (afs_indexFlags[i] & (IFDataMod | IFFree | IFDiscarded)) {
614 /* skip if dirty or already free */
617 tdc = afs_indexTable[i];
618 if (tdc && (curbucket != tdc->bucket) && (phase < 4))
620 /* Wrong bucket; can't use it! */
623 if (tdc && (tdc->refCount != 0)) {
624 /* Referenced; can't use it! */
627 hset(vtime, afs_indexTimes[i]);
629 /* if we've already looked at this one, skip it */
630 if (afs_indexFlags[i] & IFFlag)
633 if (victimPtr < MAXATONCE) {
634 /* if there's at least one free victim slot left */
635 victims[victimPtr] = i;
636 hset(victimTimes[victimPtr], vtime);
637 if (hcmp(vtime, maxVictimTime) > 0) {
638 hset(maxVictimTime, vtime);
639 maxVictimPtr = victimPtr;
642 } else if (hcmp(vtime, maxVictimTime) < 0) {
644 * We're older than youngest victim, so we replace at
647 /* find youngest (largest LRU) victim */
650 osi_Panic("getdownd local");
652 hset(victimTimes[j], vtime);
653 /* recompute maxVictimTime */
654 hset(maxVictimTime, vtime);
655 for (j = 0; j < victimPtr; j++)
656 if (hcmp(maxVictimTime, victimTimes[j]) < 0) {
657 hset(maxVictimTime, victimTimes[j]);
663 /* now really reclaim the victims */
664 j = 0; /* flag to track if we actually got any of the victims */
665 /* first, hold all the victims, since we're going to release the lock
666 * during the truncate operation.
668 for (i = 0; i < victimPtr; i++) {
669 tdc = afs_GetDSlot(victims[i], 0);
670 /* We got tdc->tlock(R) here */
671 if (tdc->refCount == 1)
675 ReleaseReadLock(&tdc->tlock);
679 for (i = 0; i < victimPtr; i++) {
680 /* q is first elt in dcache entry */
682 /* now, since we're dropping the afs_xdcache lock below, we
683 * have to verify, before proceeding, that there are no other
684 * references to this dcache entry, even now. Note that we
685 * compare with 1, since we bumped it above when we called
686 * afs_GetDSlot to preserve the entry's identity.
688 if (tdc && tdc->refCount == 1) {
689 unsigned char chunkFlags;
690 afs_size_t tchunkoffset = 0;
692 /* xdcache is lower than the xvcache lock */
693 MReleaseWriteLock(&afs_xdcache);
694 MObtainReadLock(&afs_xvcache);
695 tvc = afs_FindVCache(afid, 0, 0 /* no stats, no vlru */ );
696 MReleaseReadLock(&afs_xvcache);
697 MObtainWriteLock(&afs_xdcache, 527);
699 if (tdc->refCount > 1)
702 tchunkoffset = AFS_CHUNKTOBASE(tdc->f.chunk);
703 chunkFlags = afs_indexFlags[tdc->index];
704 if (((phase & 1) == 0) && osi_Active(tvc))
706 if (((phase & 1) == 1) && osi_Active(tvc)
707 && (tvc->f.states & CDCLock)
708 && (chunkFlags & IFAnyPages))
710 if (chunkFlags & IFDataMod)
712 afs_Trace4(afs_iclSetp, CM_TRACE_GETDOWND,
713 ICL_TYPE_POINTER, tvc, ICL_TYPE_INT32, skip,
714 ICL_TYPE_INT32, tdc->index, ICL_TYPE_OFFSET,
715 ICL_HANDLE_OFFSET(tchunkoffset));
717 #if defined(AFS_SUN5_ENV)
719 * Now we try to invalidate pages. We do this only for
720 * Solaris. For other platforms, it's OK to recycle a
721 * dcache entry out from under a page, because the strategy
722 * function can call afs_GetDCache().
724 if (!skip && (chunkFlags & IFAnyPages)) {
727 MReleaseWriteLock(&afs_xdcache);
728 MObtainWriteLock(&tvc->vlock, 543);
729 if (tvc->multiPage) {
733 /* block locking pages */
734 tvc->vstates |= VPageCleaning;
735 /* block getting new pages */
737 MReleaseWriteLock(&tvc->vlock);
738 /* One last recheck */
739 MObtainWriteLock(&afs_xdcache, 333);
740 chunkFlags = afs_indexFlags[tdc->index];
741 if (tdc->refCount > 1 || (chunkFlags & IFDataMod)
742 || (osi_Active(tvc) && (tvc->f.states & CDCLock)
743 && (chunkFlags & IFAnyPages))) {
745 MReleaseWriteLock(&afs_xdcache);
748 MReleaseWriteLock(&afs_xdcache);
750 code = osi_VM_GetDownD(tvc, tdc);
752 MObtainWriteLock(&afs_xdcache, 269);
753 /* we actually removed all pages, clean and dirty */
755 afs_indexFlags[tdc->index] &=
756 ~(IFDirtyPages | IFAnyPages);
759 MReleaseWriteLock(&afs_xdcache);
761 MObtainWriteLock(&tvc->vlock, 544);
762 if (--tvc->activeV == 0
763 && (tvc->vstates & VRevokeWait)) {
764 tvc->vstates &= ~VRevokeWait;
765 afs_osi_Wakeup((char *)&tvc->vstates);
768 if (tvc->vstates & VPageCleaning) {
769 tvc->vstates &= ~VPageCleaning;
770 afs_osi_Wakeup((char *)&tvc->vstates);
773 MReleaseWriteLock(&tvc->vlock);
775 #endif /* AFS_SUN5_ENV */
777 MReleaseWriteLock(&afs_xdcache);
780 afs_PutVCache(tvc); /*XXX was AFS_FAST_RELE?*/
781 MObtainWriteLock(&afs_xdcache, 528);
782 if (afs_indexFlags[tdc->index] &
783 (IFDataMod | IFDirtyPages | IFAnyPages))
785 if (tdc->refCount > 1)
788 #if defined(AFS_SUN5_ENV)
790 /* no vnode, so IFDirtyPages is spurious (we don't
791 * sweep dcaches on vnode recycling, so we can have
792 * DIRTYPAGES set even when all pages are gone). Just
794 * Hold vcache lock to prevent vnode from being
795 * created while we're clearing IFDirtyPages.
797 afs_indexFlags[tdc->index] &=
798 ~(IFDirtyPages | IFAnyPages);
802 /* skip this guy and mark him as recently used */
803 afs_indexFlags[tdc->index] |= IFFlag;
804 afs_Trace4(afs_iclSetp, CM_TRACE_GETDOWND,
805 ICL_TYPE_POINTER, tvc, ICL_TYPE_INT32, 2,
806 ICL_TYPE_INT32, tdc->index, ICL_TYPE_OFFSET,
807 ICL_HANDLE_OFFSET(tchunkoffset));
809 /* flush this dude from the data cache and reclaim;
810 * first, make sure no one will care that we damage
811 * it, by removing it from all hash tables. Then,
812 * melt it down for parts. Note that any concurrent
813 * (new possibility!) calls to GetDownD won't touch
814 * this guy because his reference count is > 0. */
815 afs_Trace4(afs_iclSetp, CM_TRACE_GETDOWND,
816 ICL_TYPE_POINTER, tvc, ICL_TYPE_INT32, 3,
817 ICL_TYPE_INT32, tdc->index, ICL_TYPE_OFFSET,
818 ICL_HANDLE_OFFSET(tchunkoffset));
819 AFS_STATCNT(afs_gget);
820 afs_HashOutDCache(tdc, 1);
821 if (tdc->f.chunkBytes != 0) {
825 (tdc->f.chunkBytes + afs_fsfragsize) >> 10;
830 afs_DiscardDCache(tdc);
835 j = 1; /* we reclaimed at least one victim */
839 } /* end of for victims loop */
842 /* Phase is 0 and no one was found, so try phase 1 (ignore
843 * osi_Active flag) */
846 for (i = 0; i < afs_cacheFiles; i++)
847 /* turn off all flags */
848 afs_indexFlags[i] &= ~IFFlag;
851 /* found no one in phases 0-5, we're hosed */
855 } /* big while loop */
857 #if defined(AFS_FBSD80_ENV) && !defined(UKERNEL)
858 VFS_UNLOCK_GIANT(vfslocked);
867 * Remove adc from any hash tables that would allow it to be located
868 * again by afs_FindDCache or afs_GetDCache.
870 * \param adc Pointer to dcache entry to remove from hash tables.
872 * \note Locks: Must have the afs_xdcache lock write-locked to call this function.
876 afs_HashOutDCache(struct dcache *adc, int zap)
880 AFS_STATCNT(afs_glink);
882 /* we know this guy's in the LRUQ. We'll move dude into DCQ below */
884 /* if this guy is in the hash table, pull him out */
885 if (adc->f.fid.Fid.Volume != 0) {
886 /* remove entry from first hash chains */
887 i = DCHash(&adc->f.fid, adc->f.chunk);
888 us = afs_dchashTbl[i];
889 if (us == adc->index) {
890 /* first dude in the list */
891 afs_dchashTbl[i] = afs_dcnextTbl[adc->index];
893 /* somewhere on the chain */
894 while (us != NULLIDX) {
895 if (afs_dcnextTbl[us] == adc->index) {
896 /* found item pointing at the one to delete */
897 afs_dcnextTbl[us] = afs_dcnextTbl[adc->index];
900 us = afs_dcnextTbl[us];
903 osi_Panic("dcache hc");
905 /* remove entry from *other* hash chain */
906 i = DVHash(&adc->f.fid);
907 us = afs_dvhashTbl[i];
908 if (us == adc->index) {
909 /* first dude in the list */
910 afs_dvhashTbl[i] = afs_dvnextTbl[adc->index];
912 /* somewhere on the chain */
913 while (us != NULLIDX) {
914 if (afs_dvnextTbl[us] == adc->index) {
915 /* found item pointing at the one to delete */
916 afs_dvnextTbl[us] = afs_dvnextTbl[adc->index];
919 us = afs_dvnextTbl[us];
922 osi_Panic("dcache hv");
927 /* prevent entry from being found on a reboot (it is already out of
928 * the hash table, but after a crash, we just look at fid fields of
929 * stable (old) entries).
931 adc->f.fid.Fid.Volume = 0; /* invalid */
933 /* mark entry as modified */
934 adc->dflags |= DFEntryMod;
939 } /*afs_HashOutDCache */
942 * Flush the given dcache entry, pulling it from hash chains
943 * and truncating the associated cache file.
945 * \param adc Ptr to dcache entry to flush.
948 * This routine must be called with the afs_xdcache lock held
952 afs_FlushDCache(register struct dcache *adc)
954 AFS_STATCNT(afs_FlushDCache);
956 * Bump the number of cache files flushed.
958 afs_stats_cmperf.cacheFlushes++;
960 /* remove from all hash tables */
961 afs_HashOutDCache(adc, 1);
963 /* Free its space; special case null operation, since truncate operation
964 * in UFS is slow even in this case, and this allows us to pre-truncate
965 * these files at more convenient times with fewer locks set
966 * (see afs_GetDownD).
968 if (adc->f.chunkBytes != 0) {
969 afs_DiscardDCache(adc);
970 afs_MaybeWakeupTruncateDaemon();
975 if (afs_WaitForCacheDrain) {
976 if (afs_blocksUsed <=
977 PERCENT(CM_CACHESIZEDRAINEDPCT, afs_cacheBlocks)) {
978 afs_WaitForCacheDrain = 0;
979 afs_osi_Wakeup(&afs_WaitForCacheDrain);
982 } /*afs_FlushDCache */
986 * Put a dcache entry on the free dcache entry list.
988 * \param adc dcache entry to free.
990 * \note Environment: called with afs_xdcache lock write-locked.
993 afs_FreeDCache(register struct dcache *adc)
995 /* Thread on free list, update free list count and mark entry as
996 * freed in its indexFlags element. Also, ensure DCache entry gets
997 * written out (set DFEntryMod).
1000 afs_dvnextTbl[adc->index] = afs_freeDCList;
1001 afs_freeDCList = adc->index;
1003 afs_indexFlags[adc->index] |= IFFree;
1004 adc->dflags |= DFEntryMod;
1006 if (afs_WaitForCacheDrain) {
1007 if ((afs_blocksUsed - afs_blocksDiscarded) <=
1008 PERCENT(CM_CACHESIZEDRAINEDPCT, afs_cacheBlocks)) {
1009 afs_WaitForCacheDrain = 0;
1010 afs_osi_Wakeup(&afs_WaitForCacheDrain);
1013 } /* afs_FreeDCache */
1016 * Discard the cache element by moving it to the discardDCList.
1017 * This puts the cache element into a quasi-freed state, where
1018 * the space may be reused, but the file has not been truncated.
1020 * \note Major Assumptions Here:
1021 * Assumes that frag size is an integral power of two, less one,
1022 * and that this is a two's complement machine. I don't
1023 * know of any filesystems which violate this assumption...
1025 * \param adr Ptr to dcache entry.
1027 * \note Environment:
1028 * Must be called with afs_xdcache write-locked.
1032 afs_DiscardDCache(register struct dcache *adc)
1034 register afs_int32 size;
1036 AFS_STATCNT(afs_DiscardDCache);
1038 osi_Assert(adc->refCount == 1);
1040 size = ((adc->f.chunkBytes + afs_fsfragsize) ^ afs_fsfragsize) >> 10; /* round up */
1041 afs_blocksDiscarded += size;
1042 afs_stats_cmperf.cacheBlocksDiscarded = afs_blocksDiscarded;
1044 afs_dvnextTbl[adc->index] = afs_discardDCList;
1045 afs_discardDCList = adc->index;
1046 afs_discardDCCount++;
1048 adc->f.fid.Fid.Volume = 0;
1049 adc->dflags |= DFEntryMod;
1050 afs_indexFlags[adc->index] |= IFDiscarded;
1052 if (afs_WaitForCacheDrain) {
1053 if ((afs_blocksUsed - afs_blocksDiscarded) <=
1054 PERCENT(CM_CACHESIZEDRAINEDPCT, afs_cacheBlocks)) {
1055 afs_WaitForCacheDrain = 0;
1056 afs_osi_Wakeup(&afs_WaitForCacheDrain);
1060 } /*afs_DiscardDCache */
1063 * Free the next element on the list of discarded cache elements.
1066 afs_FreeDiscardedDCache(void)
1068 register struct dcache *tdc;
1069 register struct osi_file *tfile;
1070 register afs_int32 size;
1072 AFS_STATCNT(afs_FreeDiscardedDCache);
1074 MObtainWriteLock(&afs_xdcache, 510);
1075 if (!afs_blocksDiscarded) {
1076 MReleaseWriteLock(&afs_xdcache);
1081 * Get an entry from the list of discarded cache elements
1083 tdc = afs_GetDSlot(afs_discardDCList, 0);
1084 osi_Assert(tdc->refCount == 1);
1085 ReleaseReadLock(&tdc->tlock);
1087 afs_discardDCList = afs_dvnextTbl[tdc->index];
1088 afs_dvnextTbl[tdc->index] = NULLIDX;
1089 afs_discardDCCount--;
1090 size = ((tdc->f.chunkBytes + afs_fsfragsize) ^ afs_fsfragsize) >> 10; /* round up */
1091 afs_blocksDiscarded -= size;
1092 afs_stats_cmperf.cacheBlocksDiscarded = afs_blocksDiscarded;
1093 /* We can lock because we just took it off the free list */
1094 ObtainWriteLock(&tdc->lock, 626);
1095 MReleaseWriteLock(&afs_xdcache);
1098 * Truncate the element to reclaim its space
1100 tfile = afs_CFileOpen(&tdc->f.inode);
1101 afs_CFileTruncate(tfile, 0);
1102 afs_CFileClose(tfile);
1103 afs_AdjustSize(tdc, 0);
1104 afs_DCMoveBucket(tdc, 0, 0);
1107 * Free the element we just truncated
1109 MObtainWriteLock(&afs_xdcache, 511);
1110 afs_indexFlags[tdc->index] &= ~IFDiscarded;
1111 afs_FreeDCache(tdc);
1112 tdc->f.states &= ~(DRO|DBackup|DRW);
1113 ReleaseWriteLock(&tdc->lock);
1115 MReleaseWriteLock(&afs_xdcache);
1119 * Free as many entries from the list of discarded cache elements
1120 * as we need to get the free space down below CM_WAITFORDRAINPCT (98%).
1125 afs_MaybeFreeDiscardedDCache(void)
1128 AFS_STATCNT(afs_MaybeFreeDiscardedDCache);
1130 while (afs_blocksDiscarded
1131 && (afs_blocksUsed >
1132 PERCENT(CM_WAITFORDRAINPCT, afs_cacheBlocks))) {
1133 afs_FreeDiscardedDCache();
1139 * Try to free up a certain number of disk slots.
1141 * \param anumber Targeted number of disk slots to free up.
1143 * \note Environment:
1144 * Must be called with afs_xdcache write-locked.
1148 afs_GetDownDSlot(int anumber)
1150 struct afs_q *tq, *nq;
1155 AFS_STATCNT(afs_GetDownDSlot);
1156 if (cacheDiskType == AFS_FCACHE_TYPE_MEM)
1157 osi_Panic("diskless getdowndslot");
1159 if (CheckLock(&afs_xdcache) != -1)
1160 osi_Panic("getdowndslot nolock");
1162 /* decrement anumber first for all dudes in free list */
1163 for (tdc = afs_freeDSList; tdc; tdc = (struct dcache *)tdc->lruq.next)
1166 return; /* enough already free */
1168 for (cnt = 0, tq = afs_DLRU.prev; tq != &afs_DLRU && anumber > 0;
1170 tdc = (struct dcache *)tq; /* q is first elt in dcache entry */
1171 nq = QPrev(tq); /* in case we remove it */
1172 if (tdc->refCount == 0) {
1173 if ((ix = tdc->index) == NULLIDX)
1174 osi_Panic("getdowndslot");
1175 /* pull the entry out of the lruq and put it on the free list */
1176 QRemove(&tdc->lruq);
1178 /* write-through if modified */
1179 if (tdc->dflags & DFEntryMod) {
1180 #if defined(AFS_SGI_ENV) && defined(AFS_SGI_SHORTSTACK)
1182 * ask proxy to do this for us - we don't have the stack space
1184 while (tdc->dflags & DFEntryMod) {
1187 s = SPLOCK(afs_sgibklock);
1188 if (afs_sgibklist == NULL) {
1189 /* if slot is free, grab it. */
1190 afs_sgibklist = tdc;
1191 SV_SIGNAL(&afs_sgibksync);
1193 /* wait for daemon to (start, then) finish. */
1194 SP_WAIT(afs_sgibklock, s, &afs_sgibkwait, PINOD);
1198 tdc->dflags &= ~DFEntryMod;
1199 afs_WriteDCache(tdc, 1);
1203 /* finally put the entry in the free list */
1204 afs_indexTable[ix] = NULL;
1205 afs_indexFlags[ix] &= ~IFEverUsed;
1206 tdc->index = NULLIDX;
1207 tdc->lruq.next = (struct afs_q *)afs_freeDSList;
1208 afs_freeDSList = tdc;
1212 } /*afs_GetDownDSlot */
1219 * Increment the reference count on a disk cache entry,
1220 * which already has a non-zero refcount. In order to
1221 * increment the refcount of a zero-reference entry, you
1222 * have to hold afs_xdcache.
1225 * adc : Pointer to the dcache entry to increment.
1228 * Nothing interesting.
1231 afs_RefDCache(struct dcache *adc)
1233 ObtainWriteLock(&adc->tlock, 627);
1234 if (adc->refCount < 0)
1235 osi_Panic("RefDCache: negative refcount");
1237 ReleaseWriteLock(&adc->tlock);
1246 * Decrement the reference count on a disk cache entry.
1249 * ad : Ptr to the dcache entry to decrement.
1252 * Nothing interesting.
1255 afs_PutDCache(register struct dcache *adc)
1257 AFS_STATCNT(afs_PutDCache);
1258 ObtainWriteLock(&adc->tlock, 276);
1259 if (adc->refCount <= 0)
1260 osi_Panic("putdcache");
1262 ReleaseWriteLock(&adc->tlock);
1271 * Try to discard all data associated with this file from the
1275 * avc : Pointer to the cache info for the file.
1278 * Both pvnLock and lock are write held.
1281 afs_TryToSmush(register struct vcache *avc, struct AFS_UCRED *acred, int sync)
1283 register struct dcache *tdc;
1286 AFS_STATCNT(afs_TryToSmush);
1287 afs_Trace2(afs_iclSetp, CM_TRACE_TRYTOSMUSH, ICL_TYPE_POINTER, avc,
1288 ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(avc->f.m.Length));
1289 sync = 1; /* XX Temp testing XX */
1291 #if defined(AFS_SUN5_ENV)
1292 ObtainWriteLock(&avc->vlock, 573);
1293 avc->activeV++; /* block new getpages */
1294 ReleaseWriteLock(&avc->vlock);
1297 /* Flush VM pages */
1298 osi_VM_TryToSmush(avc, acred, sync);
1301 * Get the hash chain containing all dce's for this fid
1303 i = DVHash(&avc->f.fid);
1304 MObtainWriteLock(&afs_xdcache, 277);
1305 for (index = afs_dvhashTbl[i]; index != NULLIDX; index = i) {
1306 i = afs_dvnextTbl[index]; /* next pointer this hash table */
1307 if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) {
1308 int releaseTlock = 1;
1309 tdc = afs_GetDSlot(index, NULL);
1310 if (!FidCmp(&tdc->f.fid, &avc->f.fid)) {
1312 if ((afs_indexFlags[index] & IFDataMod) == 0
1313 && tdc->refCount == 1) {
1314 ReleaseReadLock(&tdc->tlock);
1316 afs_FlushDCache(tdc);
1319 afs_indexTable[index] = 0;
1322 ReleaseReadLock(&tdc->tlock);
1326 #if defined(AFS_SUN5_ENV)
1327 ObtainWriteLock(&avc->vlock, 545);
1328 if (--avc->activeV == 0 && (avc->vstates & VRevokeWait)) {
1329 avc->vstates &= ~VRevokeWait;
1330 afs_osi_Wakeup((char *)&avc->vstates);
1332 ReleaseWriteLock(&avc->vlock);
1334 MReleaseWriteLock(&afs_xdcache);
1336 * It's treated like a callback so that when we do lookups we'll
1337 * invalidate the unique bit if any
1338 * trytoSmush occured during the lookup call
1344 * afs_DCacheMissingChunks
1347 * Given the cached info for a file, return the number of chunks that
1348 * are not available from the dcache.
1351 * avc: Pointer to the (held) vcache entry to look in.
1354 * The number of chunks which are not currently cached.
1357 * The vcache entry is held upon entry.
1361 afs_DCacheMissingChunks(struct vcache *avc)
1364 afs_size_t totalLength = 0;
1365 afs_uint32 totalChunks = 0;
1368 totalLength = avc->f.m.Length;
1369 if (avc->f.truncPos < totalLength)
1370 totalLength = avc->f.truncPos;
1372 /* Length is 0, no chunk missing. */
1373 if (totalLength == 0)
1376 /* If totalLength is a multiple of chunksize, the last byte appears
1377 * as being part of the next chunk, which does not exist.
1378 * Decrementing totalLength by one fixes that.
1381 totalChunks = (AFS_CHUNK(totalLength) + 1);
1383 /* If we're a directory, we only ever have one chunk, regardless of
1384 * the size of the dir.
1386 if (avc->f.fid.Fid.Vnode & 1 || vType(avc) == VDIR)
1390 printf("Should have %d chunks for %u bytes\n",
1391 totalChunks, (totalLength + 1));
1393 i = DVHash(&avc->f.fid);
1394 MObtainWriteLock(&afs_xdcache, 1001);
1395 for (index = afs_dvhashTbl[i]; index != NULLIDX; index = i) {
1396 i = afs_dvnextTbl[index];
1397 if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) {
1398 tdc = afs_GetDSlot(index, NULL);
1399 if (!FidCmp(&tdc->f.fid, &avc->f.fid)) {
1402 ReleaseReadLock(&tdc->tlock);
1406 MReleaseWriteLock(&afs_xdcache);
1408 /*printf("Missing %d chunks\n", totalChunks);*/
1410 return (totalChunks);
1417 * Given the cached info for a file and a byte offset into the
1418 * file, make sure the dcache entry for that file and containing
1419 * the given byte is available, returning it to our caller.
1422 * avc : Pointer to the (held) vcache entry to look in.
1423 * abyte : Which byte we want to get to.
1426 * Pointer to the dcache entry covering the file & desired byte,
1427 * or NULL if not found.
1430 * The vcache entry is held upon entry.
1434 afs_FindDCache(register struct vcache *avc, afs_size_t abyte)
1437 register afs_int32 i, index;
1438 register struct dcache *tdc = NULL;
1440 AFS_STATCNT(afs_FindDCache);
1441 chunk = AFS_CHUNK(abyte);
1444 * Hash on the [fid, chunk] and get the corresponding dcache index
1445 * after write-locking the dcache.
1447 i = DCHash(&avc->f.fid, chunk);
1448 MObtainWriteLock(&afs_xdcache, 278);
1449 for (index = afs_dchashTbl[i]; index != NULLIDX;) {
1450 if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) {
1451 tdc = afs_GetDSlot(index, NULL);
1452 ReleaseReadLock(&tdc->tlock);
1453 if (!FidCmp(&tdc->f.fid, &avc->f.fid) && chunk == tdc->f.chunk) {
1454 break; /* leaving refCount high for caller */
1458 index = afs_dcnextTbl[index];
1460 if (index != NULLIDX) {
1461 hset(afs_indexTimes[tdc->index], afs_indexCounter);
1462 hadd32(afs_indexCounter, 1);
1463 MReleaseWriteLock(&afs_xdcache);
1466 MReleaseWriteLock(&afs_xdcache);
1468 } /*afs_FindDCache */
1472 * afs_UFSCacheStoreProc
1475 * Called upon store.
1478 * acall : Ptr to the Rx call structure involved.
1479 * afile : Ptr to the related file descriptor.
1480 * alen : Size of the file in bytes.
1481 * avc : Ptr to the vcache entry.
1482 * shouldWake : is it "safe" to return early from close() ?
1483 * abytesToXferP : Set to the number of bytes to xfer.
1484 * NOTE: This parameter is only used if AFS_NOSTATS
1486 * abytesXferredP : Set to the number of bytes actually xferred.
1487 * NOTE: This parameter is only used if AFS_NOSTATS
1491 * Nothing interesting.
1494 afs_UFSCacheStoreProc(register struct rx_call *acall, struct osi_file *afile,
1495 register afs_int32 alen, struct vcache *avc,
1496 int *shouldWake, afs_size_t * abytesToXferP,
1497 afs_size_t * abytesXferredP)
1499 afs_int32 code, got;
1500 register char *tbuffer;
1503 AFS_STATCNT(UFS_CacheStoreProc);
1507 * In this case, alen is *always* the amount of data we'll be trying
1510 (*abytesToXferP) = alen;
1511 (*abytesXferredP) = 0;
1512 #endif /* AFS_NOSTATS */
1514 afs_Trace4(afs_iclSetp, CM_TRACE_STOREPROC, ICL_TYPE_POINTER, avc,
1515 ICL_TYPE_FID, &(avc->f.fid), ICL_TYPE_OFFSET,
1516 ICL_HANDLE_OFFSET(avc->f.m.Length), ICL_TYPE_INT32, alen);
1517 tbuffer = osi_AllocLargeSpace(AFS_LRALLOCSIZ);
1519 tlen = (alen > AFS_LRALLOCSIZ ? AFS_LRALLOCSIZ : alen);
1520 got = afs_osi_Read(afile, -1, tbuffer, tlen);
1522 #if defined(KERNEL_HAVE_UERROR)
1523 || (got != tlen && getuerror())
1526 osi_FreeLargeSpace(tbuffer);
1529 afs_Trace2(afs_iclSetp, CM_TRACE_STOREPROC2, ICL_TYPE_OFFSET,
1530 ICL_HANDLE_OFFSET(*tbuffer), ICL_TYPE_INT32, got);
1532 code = rx_Write(acall, tbuffer, got); /* writing 0 bytes will
1533 * push a short packet. Is that really what we want, just because the
1534 * data didn't come back from the disk yet? Let's try it and see. */
1537 (*abytesXferredP) += code;
1538 #endif /* AFS_NOSTATS */
1540 code = rx_Error(acall);
1541 osi_FreeLargeSpace(tbuffer);
1542 return code ? code : -33;
1546 * If file has been locked on server, we can allow the store
1549 if (shouldWake && *shouldWake && (rx_GetRemoteStatus(acall) & 1)) {
1550 *shouldWake = 0; /* only do this once */
1554 afs_Trace4(afs_iclSetp, CM_TRACE_STOREPROC, ICL_TYPE_POINTER, avc,
1555 ICL_TYPE_FID, &(avc->f.fid), ICL_TYPE_OFFSET,
1556 ICL_HANDLE_OFFSET(avc->f.m.Length), ICL_TYPE_INT32, alen);
1557 osi_FreeLargeSpace(tbuffer);
1560 } /* afs_UFSCacheStoreProc */
1564 * afs_UFSCacheFetchProc
1567 * Routine called on fetch; also tells people waiting for data
1568 * that more has arrived.
1571 * acall : Ptr to the Rx call structure.
1572 * afile : File descriptor for the cache file.
1573 * abase : Base offset to fetch.
1574 * adc : Ptr to the dcache entry for the file, write-locked.
1575 * avc : Ptr to the vcache entry for the file.
1576 * abytesToXferP : Set to the number of bytes to xfer.
1577 * NOTE: This parameter is only used if AFS_NOSTATS
1579 * abytesXferredP : Set to the number of bytes actually xferred.
1580 * NOTE: This parameter is only used if AFS_NOSTATS
1584 * Nothing interesting.
1588 afs_UFSCacheFetchProc(register struct rx_call *acall, struct osi_file *afile,
1589 afs_size_t abase, struct dcache *adc,
1590 struct vcache *avc, afs_size_t * abytesToXferP,
1591 afs_size_t * abytesXferredP, afs_int32 lengthFound)
1594 register afs_int32 code;
1595 register char *tbuffer;
1599 AFS_STATCNT(UFS_CacheFetchProc);
1600 osi_Assert(WriteLocked(&adc->lock));
1601 afile->offset = 0; /* Each time start from the beginning */
1602 length = lengthFound;
1604 (*abytesToXferP) = 0;
1605 (*abytesXferredP) = 0;
1606 #endif /* AFS_NOSTATS */
1607 tbuffer = osi_AllocLargeSpace(AFS_LRALLOCSIZ);
1608 adc->validPos = abase;
1612 code = rx_Read(acall, (char *)&length, sizeof(afs_int32));
1614 length = ntohl(length);
1615 if (code != sizeof(afs_int32)) {
1616 osi_FreeLargeSpace(tbuffer);
1617 code = rx_Error(acall);
1618 return (code ? code : -1); /* try to return code, not -1 */
1622 * The fetch protocol is extended for the AFS/DFS translator
1623 * to allow multiple blocks of data, each with its own length,
1624 * to be returned. As long as the top bit is set, there are more
1627 * We do not do this for AFS file servers because they sometimes
1628 * return large negative numbers as the transfer size.
1630 if (avc->f.states & CForeign) {
1631 moredata = length & 0x80000000;
1632 length &= ~0x80000000;
1637 (*abytesToXferP) += length;
1638 #endif /* AFS_NOSTATS */
1639 while (length > 0) {
1640 tlen = (length > AFS_LRALLOCSIZ ? AFS_LRALLOCSIZ : length);
1641 #ifdef RX_KERNEL_TRACE
1642 afs_Trace1(afs_iclSetp, CM_TRACE_TIMESTAMP, ICL_TYPE_STRING,
1646 code = rx_Read(acall, tbuffer, tlen);
1648 #ifdef RX_KERNEL_TRACE
1649 afs_Trace1(afs_iclSetp, CM_TRACE_TIMESTAMP, ICL_TYPE_STRING,
1653 (*abytesXferredP) += code;
1654 #endif /* AFS_NOSTATS */
1656 osi_FreeLargeSpace(tbuffer);
1657 afs_Trace3(afs_iclSetp, CM_TRACE_FETCH64READ,
1658 ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, code,
1659 ICL_TYPE_INT32, length);
1662 code = afs_osi_Write(afile, -1, tbuffer, tlen);
1664 osi_FreeLargeSpace(tbuffer);
1669 adc->validPos = abase;
1670 if (afs_osi_Wakeup(&adc->validPos) == 0)
1671 afs_Trace4(afs_iclSetp, CM_TRACE_DCACHEWAKE, ICL_TYPE_STRING,
1672 __FILE__, ICL_TYPE_INT32, __LINE__,
1673 ICL_TYPE_POINTER, adc, ICL_TYPE_INT32,
1677 osi_FreeLargeSpace(tbuffer);
1680 } /* afs_UFSCacheFetchProc */
1683 * Get a fresh dcache from the free or discarded list.
1685 * \param avc Who's dcache is this going to be?
1686 * \param chunk The position where it will be placed in.
1687 * \param lock How are locks held.
1688 * \param ashFid If this dcache going to be used for a shadow dir,
1691 * \note Required locks:
1693 * - avc (R if (lock & 1) set and W otherwise)
1694 * \note It write locks the new dcache. The caller must unlock it.
1696 * \return The new dcache.
1698 struct dcache *afs_AllocDCache(struct vcache *avc,
1701 struct VenusFid *ashFid)
1703 struct dcache *tdc = NULL;
1704 afs_uint32 size = 0;
1705 struct osi_file *file;
1707 if (afs_discardDCList == NULLIDX
1708 || ((lock & 2) && afs_freeDCList != NULLIDX)) {
1710 afs_indexFlags[afs_freeDCList] &= ~IFFree;
1711 tdc = afs_GetDSlot(afs_freeDCList, 0);
1712 osi_Assert(tdc->refCount == 1);
1713 ReleaseReadLock(&tdc->tlock);
1714 ObtainWriteLock(&tdc->lock, 604);
1715 afs_freeDCList = afs_dvnextTbl[tdc->index];
1718 afs_indexFlags[afs_discardDCList] &= ~IFDiscarded;
1719 tdc = afs_GetDSlot(afs_discardDCList, 0);
1720 osi_Assert(tdc->refCount == 1);
1721 ReleaseReadLock(&tdc->tlock);
1722 ObtainWriteLock(&tdc->lock, 605);
1723 afs_discardDCList = afs_dvnextTbl[tdc->index];
1724 afs_discardDCCount--;
1726 ((tdc->f.chunkBytes +
1727 afs_fsfragsize) ^ afs_fsfragsize) >> 10;
1728 tdc->f.states &= ~(DRO|DBackup|DRW);
1729 afs_DCMoveBucket(tdc, size, 0);
1730 afs_blocksDiscarded -= size;
1731 afs_stats_cmperf.cacheBlocksDiscarded = afs_blocksDiscarded;
1733 /* Truncate the chunk so zeroes get filled properly */
1734 file = afs_CFileOpen(&tdc->f.inode);
1735 afs_CFileTruncate(file, 0);
1736 afs_CFileClose(file);
1737 afs_AdjustSize(tdc, 0);
1743 * avc->lock(R) if setLocks
1744 * avc->lock(W) if !setLocks
1750 * Fill in the newly-allocated dcache record.
1752 afs_indexFlags[tdc->index] &= ~(IFDirtyPages | IFAnyPages);
1754 /* Use shadow fid if provided. */
1755 tdc->f.fid = *ashFid;
1757 /* Use normal vcache's fid otherwise. */
1758 tdc->f.fid = avc->f.fid;
1759 if (avc->f.states & CRO)
1760 tdc->f.states = DRO;
1761 else if (avc->f.states & CBackup)
1762 tdc->f.states = DBackup;
1764 tdc->f.states = DRW;
1765 afs_DCMoveBucket(tdc, 0, afs_DCGetBucket(avc));
1766 afs_indexUnique[tdc->index] = tdc->f.fid.Fid.Unique;
1768 hones(tdc->f.versionNo); /* invalid value */
1769 tdc->f.chunk = chunk;
1770 tdc->validPos = AFS_CHUNKTOBASE(chunk);
1772 if (tdc->lruq.prev == &tdc->lruq)
1773 osi_Panic("lruq 1");
1782 * This function is called to obtain a reference to data stored in
1783 * the disk cache, locating a chunk of data containing the desired
1784 * byte and returning a reference to the disk cache entry, with its
1785 * reference count incremented.
1789 * avc : Ptr to a vcache entry (unlocked)
1790 * abyte : Byte position in the file desired
1791 * areq : Request structure identifying the requesting user.
1792 * aflags : Settings as follows:
1794 * 2 : Return after creating entry.
1795 * 4 : called from afs_vnop_write.c
1796 * *alen contains length of data to be written.
1798 * aoffset : Set to the offset within the chunk where the resident
1800 * alen : Set to the number of bytes of data after the desired
1801 * byte (including the byte itself) which can be read
1805 * The vcache entry pointed to by avc is unlocked upon entry.
1809 struct AFSVolSync tsync;
1810 struct AFSFetchStatus OutStatus;
1811 struct AFSCallBack CallBack;
1815 * Update the vnode-to-dcache hint if we can get the vnode lock
1816 * right away. Assumes dcache entry is at least read-locked.
1819 updateV2DC(int lockVc, struct vcache *v, struct dcache *d, int src)
1821 if (!lockVc || 0 == NBObtainWriteLock(&v->lock, src)) {
1822 if (hsame(v->f.m.DataVersion, d->f.versionNo) && v->callback)
1825 ReleaseWriteLock(&v->lock);
1829 /* avc - Write-locked unless aflags & 1 */
1831 afs_GetDCache(register struct vcache *avc, afs_size_t abyte,
1832 register struct vrequest *areq, afs_size_t * aoffset,
1833 afs_size_t * alen, int aflags)
1835 register afs_int32 i, code, code1 = 0, shortcut;
1836 #if defined(AFS_AIX32_ENV) || defined(AFS_SGI_ENV)
1837 register afs_int32 adjustsize = 0;
1843 afs_size_t maxGoodLength; /* amount of good data at server */
1844 struct rx_call *tcall;
1845 afs_size_t Position = 0;
1846 #ifdef AFS_64BIT_CLIENT
1848 afs_size_t lengthFound; /* as returned from server */
1849 #endif /* AFS_64BIT_CLIENT */
1850 afs_int32 size, tlen; /* size of segment to transfer */
1851 struct tlocal1 *tsmall = 0;
1852 register struct dcache *tdc;
1853 register struct osi_file *file;
1854 register struct afs_conn *tc;
1856 struct server *newCallback = NULL;
1857 char setNewCallback;
1858 char setVcacheStatus;
1859 char doVcacheUpdate;
1861 int doAdjustSize = 0;
1862 int doReallyAdjustSize = 0;
1863 int overWriteWholeChunk = 0;
1867 struct afs_stats_xferData *xferP; /* Ptr to this op's xfer struct */
1868 osi_timeval_t xferStartTime, /*FS xfer start time */
1869 xferStopTime; /*FS xfer stop time */
1870 afs_size_t bytesToXfer; /* # bytes to xfer */
1871 afs_size_t bytesXferred; /* # bytes actually xferred */
1872 struct afs_stats_AccessInfo *accP; /*Ptr to access record in stats */
1873 int fromReplica; /*Are we reading from a replica? */
1874 int numFetchLoops; /*# times around the fetch/analyze loop */
1875 #endif /* AFS_NOSTATS */
1877 AFS_STATCNT(afs_GetDCache);
1881 setLocks = aflags & 1;
1884 * Determine the chunk number and offset within the chunk corresponding
1885 * to the desired byte.
1887 if (avc->f.fid.Fid.Vnode & 1) { /* if (vType(avc) == VDIR) */
1890 chunk = AFS_CHUNK(abyte);
1893 /* come back to here if we waited for the cache to drain. */
1896 setNewCallback = setVcacheStatus = 0;
1900 ObtainWriteLock(&avc->lock, 616);
1902 ObtainReadLock(&avc->lock);
1907 * avc->lock(R) if setLocks && !slowPass
1908 * avc->lock(W) if !setLocks || slowPass
1913 /* check hints first! (might could use bcmp or some such...) */
1914 if ((tdc = avc->dchint)) {
1918 * The locking order between afs_xdcache and dcache lock matters.
1919 * The hint dcache entry could be anywhere, even on the free list.
1920 * Locking afs_xdcache ensures that noone is trying to pull dcache
1921 * entries from the free list, and thereby assuming them to be not
1922 * referenced and not locked.
1924 MObtainReadLock(&afs_xdcache);
1925 dcLocked = (0 == NBObtainSharedLock(&tdc->lock, 601));
1927 if (dcLocked && (tdc->index != NULLIDX)
1928 && !FidCmp(&tdc->f.fid, &avc->f.fid) && chunk == tdc->f.chunk
1929 && !(afs_indexFlags[tdc->index] & (IFFree | IFDiscarded))) {
1930 /* got the right one. It might not be the right version, and it
1931 * might be fetching, but it's the right dcache entry.
1933 /* All this code should be integrated better with what follows:
1934 * I can save a good bit more time under a write lock if I do..
1936 ObtainWriteLock(&tdc->tlock, 603);
1938 ReleaseWriteLock(&tdc->tlock);
1940 MReleaseReadLock(&afs_xdcache);
1943 if (hsame(tdc->f.versionNo, avc->f.m.DataVersion)
1944 && !(tdc->dflags & DFFetching)) {
1946 afs_stats_cmperf.dcacheHits++;
1947 MObtainWriteLock(&afs_xdcache, 559);
1948 QRemove(&tdc->lruq);
1949 QAdd(&afs_DLRU, &tdc->lruq);
1950 MReleaseWriteLock(&afs_xdcache);
1953 * avc->lock(R) if setLocks && !slowPass
1954 * avc->lock(W) if !setLocks || slowPass
1961 ReleaseSharedLock(&tdc->lock);
1962 MReleaseReadLock(&afs_xdcache);
1970 * avc->lock(R) if setLocks && !slowPass
1971 * avc->lock(W) if !setLocks || slowPass
1972 * tdc->lock(S) if tdc
1975 if (!tdc) { /* If the hint wasn't the right dcache entry */
1977 * Hash on the [fid, chunk] and get the corresponding dcache index
1978 * after write-locking the dcache.
1983 * avc->lock(R) if setLocks && !slowPass
1984 * avc->lock(W) if !setLocks || slowPass
1987 i = DCHash(&avc->f.fid, chunk);
1988 /* check to make sure our space is fine */
1989 afs_MaybeWakeupTruncateDaemon();
1991 MObtainWriteLock(&afs_xdcache, 280);
1993 for (index = afs_dchashTbl[i]; index != NULLIDX;) {
1994 if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) {
1995 tdc = afs_GetDSlot(index, NULL);
1996 ReleaseReadLock(&tdc->tlock);
1999 * avc->lock(R) if setLocks && !slowPass
2000 * avc->lock(W) if !setLocks || slowPass
2003 if (!FidCmp(&tdc->f.fid, &avc->f.fid) && chunk == tdc->f.chunk) {
2004 /* Move it up in the beginning of the list */
2005 if (afs_dchashTbl[i] != index) {
2006 afs_dcnextTbl[us] = afs_dcnextTbl[index];
2007 afs_dcnextTbl[index] = afs_dchashTbl[i];
2008 afs_dchashTbl[i] = index;
2010 MReleaseWriteLock(&afs_xdcache);
2011 ObtainSharedLock(&tdc->lock, 606);
2012 break; /* leaving refCount high for caller */
2018 index = afs_dcnextTbl[index];
2022 * If we didn't find the entry, we'll create one.
2024 if (index == NULLIDX) {
2027 * avc->lock(R) if setLocks
2028 * avc->lock(W) if !setLocks
2031 afs_Trace2(afs_iclSetp, CM_TRACE_GETDCACHE1, ICL_TYPE_POINTER,
2032 avc, ICL_TYPE_INT32, chunk);
2034 /* Make sure there is a free dcache entry for us to use */
2035 if (afs_discardDCList == NULLIDX && afs_freeDCList == NULLIDX) {
2038 avc->f.states |= CDCLock;
2039 /* just need slots */
2040 afs_GetDownD(5, (int *)0, afs_DCGetBucket(avc));
2042 avc->f.states &= ~CDCLock;
2043 if (afs_discardDCList != NULLIDX
2044 || afs_freeDCList != NULLIDX)
2046 /* If we can't get space for 5 mins we give up and panic */
2047 if (++downDCount > 300) {
2048 #if defined(AFS_CACHE_BYPASS)
2049 afs_warn("GetDCache calling osi_Panic: No space in five minutes.\n downDCount: %d\n aoffset: %d alen: %d\n", downDCount, aoffset, alen);
2051 osi_Panic("getdcache");
2053 MReleaseWriteLock(&afs_xdcache);
2056 * avc->lock(R) if setLocks
2057 * avc->lock(W) if !setLocks
2059 afs_osi_Wait(1000, 0, 0);
2064 tdc = afs_AllocDCache(avc, chunk, aflags, NULL);
2067 * Now add to the two hash chains - note that i is still set
2068 * from the above DCHash call.
2070 afs_dcnextTbl[tdc->index] = afs_dchashTbl[i];
2071 afs_dchashTbl[i] = tdc->index;
2072 i = DVHash(&avc->f.fid);
2073 afs_dvnextTbl[tdc->index] = afs_dvhashTbl[i];
2074 afs_dvhashTbl[i] = tdc->index;
2075 tdc->dflags = DFEntryMod;
2077 afs_MaybeWakeupTruncateDaemon();
2078 MReleaseWriteLock(&afs_xdcache);
2079 ConvertWToSLock(&tdc->lock);
2084 /* vcache->dcache hint failed */
2087 * avc->lock(R) if setLocks && !slowPass
2088 * avc->lock(W) if !setLocks || slowPass
2091 afs_Trace4(afs_iclSetp, CM_TRACE_GETDCACHE2, ICL_TYPE_POINTER, avc,
2092 ICL_TYPE_POINTER, tdc, ICL_TYPE_INT32,
2093 hgetlo(tdc->f.versionNo), ICL_TYPE_INT32,
2094 hgetlo(avc->f.m.DataVersion));
2096 * Here we have the entry in tdc, with its refCount incremented.
2097 * Note: we don't use the S-lock on avc; it costs concurrency when
2098 * storing a file back to the server.
2102 * Not a newly created file so we need to check the file's length and
2103 * compare data versions since someone could have changed the data or we're
2104 * reading a file written elsewhere. We only want to bypass doing no-op
2105 * read rpcs on newly created files (dv of 0) since only then we guarantee
2106 * that this chunk's data hasn't been filled by another client.
2108 size = AFS_CHUNKSIZE(abyte);
2109 if (aflags & 4) /* called from write */
2111 else /* called from read */
2112 tlen = tdc->validPos - abyte;
2113 Position = AFS_CHUNKTOBASE(chunk);
2114 afs_Trace4(afs_iclSetp, CM_TRACE_GETDCACHE3, ICL_TYPE_INT32, tlen,
2115 ICL_TYPE_INT32, aflags, ICL_TYPE_OFFSET,
2116 ICL_HANDLE_OFFSET(abyte), ICL_TYPE_OFFSET,
2117 ICL_HANDLE_OFFSET(Position));
2118 if ((aflags & 4) && (hiszero(avc->f.m.DataVersion)))
2120 if ((AFS_CHUNKTOBASE(chunk) >= avc->f.m.Length) ||
2121 ((aflags & 4) && (abyte == Position) && (tlen >= size)))
2122 overWriteWholeChunk = 1;
2123 if (doAdjustSize || overWriteWholeChunk) {
2124 #if defined(AFS_AIX32_ENV) || defined(AFS_SGI_ENV)
2126 #ifdef AFS_SGI64_ENV
2129 #else /* AFS_SGI64_ENV */
2132 #endif /* AFS_SGI64_ENV */
2133 #else /* AFS_SGI_ENV */
2136 #endif /* AFS_SGI_ENV */
2137 if (AFS_CHUNKTOBASE(chunk) + adjustsize >= avc->f.m.Length &&
2138 #else /* defined(AFS_AIX32_ENV) || defined(AFS_SGI_ENV) */
2139 #if defined(AFS_SUN5_ENV) || defined(AFS_OSF_ENV)
2140 if ((doAdjustSize || (AFS_CHUNKTOBASE(chunk) >= avc->f.m.Length)) &&
2142 if (AFS_CHUNKTOBASE(chunk) >= avc->f.m.Length &&
2144 #endif /* defined(AFS_AIX32_ENV) || defined(AFS_SGI_ENV) */
2145 !hsame(avc->f.m.DataVersion, tdc->f.versionNo))
2146 doReallyAdjustSize = 1;
2148 if (doReallyAdjustSize || overWriteWholeChunk) {
2149 /* no data in file to read at this position */
2150 UpgradeSToWLock(&tdc->lock, 607);
2151 file = afs_CFileOpen(&tdc->f.inode);
2152 afs_CFileTruncate(file, 0);
2153 afs_CFileClose(file);
2154 afs_AdjustSize(tdc, 0);
2155 hset(tdc->f.versionNo, avc->f.m.DataVersion);
2156 tdc->dflags |= DFEntryMod;
2158 ConvertWToSLock(&tdc->lock);
2163 * We must read in the whole chunk if the version number doesn't
2167 /* don't need data, just a unique dcache entry */
2168 ObtainWriteLock(&afs_xdcache, 608);
2169 hset(afs_indexTimes[tdc->index], afs_indexCounter);
2170 hadd32(afs_indexCounter, 1);
2171 ReleaseWriteLock(&afs_xdcache);
2173 updateV2DC(setLocks, avc, tdc, 553);
2174 if (vType(avc) == VDIR)
2177 *aoffset = AFS_CHUNKOFFSET(abyte);
2178 if (tdc->validPos < abyte)
2179 *alen = (afs_size_t) 0;
2181 *alen = tdc->validPos - abyte;
2182 ReleaseSharedLock(&tdc->lock);
2185 ReleaseWriteLock(&avc->lock);
2187 ReleaseReadLock(&avc->lock);
2189 return tdc; /* check if we're done */
2194 * avc->lock(R) if setLocks && !slowPass
2195 * avc->lock(W) if !setLocks || slowPass
2198 osi_Assert((setLocks && !slowPass) || WriteLocked(&avc->lock));
2200 setNewCallback = setVcacheStatus = 0;
2204 * avc->lock(R) if setLocks && !slowPass
2205 * avc->lock(W) if !setLocks || slowPass
2208 if (!hsame(avc->f.m.DataVersion, tdc->f.versionNo) && !overWriteWholeChunk) {
2210 * Version number mismatch.
2213 * If we are disconnected, then we can't do much of anything
2214 * because the data doesn't match the file.
2216 if (AFS_IS_DISCONNECTED) {
2217 ReleaseSharedLock(&tdc->lock);
2220 ReleaseWriteLock(&avc->lock);
2222 ReleaseReadLock(&avc->lock);
2224 /* Flush the Dcache */
2229 UpgradeSToWLock(&tdc->lock, 609);
2232 * If data ever existed for this vnode, and this is a text object,
2233 * do some clearing. Now, you'd think you need only do the flush
2234 * when VTEXT is on, but VTEXT is turned off when the text object
2235 * is freed, while pages are left lying around in memory marked
2236 * with this vnode. If we would reactivate (create a new text
2237 * object from) this vnode, we could easily stumble upon some of
2238 * these old pages in pagein. So, we always flush these guys.
2239 * Sun has a wonderful lack of useful invariants in this system.
2241 * avc->flushDV is the data version # of the file at the last text
2242 * flush. Clearly, at least, we don't have to flush the file more
2243 * often than it changes
2245 if (hcmp(avc->flushDV, avc->f.m.DataVersion) < 0) {
2247 * By here, the cache entry is always write-locked. We can
2248 * deadlock if we call osi_Flush with the cache entry locked...
2249 * Unlock the dcache too.
2251 ReleaseWriteLock(&tdc->lock);
2252 if (setLocks && !slowPass)
2253 ReleaseReadLock(&avc->lock);
2255 ReleaseWriteLock(&avc->lock);
2259 * Call osi_FlushPages in open, read/write, and map, since it
2260 * is too hard here to figure out if we should lock the
2263 if (setLocks && !slowPass)
2264 ObtainReadLock(&avc->lock);
2266 ObtainWriteLock(&avc->lock, 66);
2267 ObtainWriteLock(&tdc->lock, 610);
2272 * avc->lock(R) if setLocks && !slowPass
2273 * avc->lock(W) if !setLocks || slowPass
2277 /* Watch for standard race condition around osi_FlushText */
2278 if (hsame(avc->f.m.DataVersion, tdc->f.versionNo)) {
2279 updateV2DC(setLocks, avc, tdc, 569); /* set hint */
2280 afs_stats_cmperf.dcacheHits++;
2281 ConvertWToSLock(&tdc->lock);
2285 /* Sleep here when cache needs to be drained. */
2286 if (setLocks && !slowPass
2287 && (afs_blocksUsed >
2288 PERCENT(CM_WAITFORDRAINPCT, afs_cacheBlocks))) {
2289 /* Make sure truncate daemon is running */
2290 afs_MaybeWakeupTruncateDaemon();
2291 ObtainWriteLock(&tdc->tlock, 614);
2292 tdc->refCount--; /* we'll re-obtain the dcache when we re-try. */
2293 ReleaseWriteLock(&tdc->tlock);
2294 ReleaseWriteLock(&tdc->lock);
2295 ReleaseReadLock(&avc->lock);
2296 while ((afs_blocksUsed - afs_blocksDiscarded) >
2297 PERCENT(CM_WAITFORDRAINPCT, afs_cacheBlocks)) {
2298 afs_WaitForCacheDrain = 1;
2299 afs_osi_Sleep(&afs_WaitForCacheDrain);
2301 afs_MaybeFreeDiscardedDCache();
2302 /* need to check if someone else got the chunk first. */
2303 goto RetryGetDCache;
2306 /* Do not fetch data beyond truncPos. */
2307 maxGoodLength = avc->f.m.Length;
2308 if (avc->f.truncPos < maxGoodLength)
2309 maxGoodLength = avc->f.truncPos;
2310 Position = AFS_CHUNKBASE(abyte);
2311 if (vType(avc) == VDIR) {
2312 size = avc->f.m.Length;
2313 if (size > tdc->f.chunkBytes) {
2314 /* pre-reserve space for file */
2315 afs_AdjustSize(tdc, size);
2317 size = 999999999; /* max size for transfer */
2319 size = AFS_CHUNKSIZE(abyte); /* expected max size */
2320 /* don't read past end of good data on server */
2321 if (Position + size > maxGoodLength)
2322 size = maxGoodLength - Position;
2324 size = 0; /* Handle random races */
2325 if (size > tdc->f.chunkBytes) {
2326 /* pre-reserve space for file */
2327 afs_AdjustSize(tdc, size); /* changes chunkBytes */
2328 /* max size for transfer still in size */
2331 if (afs_mariner && !tdc->f.chunk)
2332 afs_MarinerLog("fetch$Fetching", avc); /* , Position, size, afs_indexCounter ); */
2334 * Right now, we only have one tool, and it's a hammer. So, we
2335 * fetch the whole file.
2337 DZap(tdc); /* pages in cache may be old */
2338 file = afs_CFileOpen(&tdc->f.inode);
2339 afs_RemoveVCB(&avc->f.fid);
2340 tdc->f.states |= DWriting;
2341 tdc->dflags |= DFFetching;
2342 tdc->validPos = Position; /* which is AFS_CHUNKBASE(abyte) */
2343 if (tdc->mflags & DFFetchReq) {
2344 tdc->mflags &= ~DFFetchReq;
2345 if (afs_osi_Wakeup(&tdc->validPos) == 0)
2346 afs_Trace4(afs_iclSetp, CM_TRACE_DCACHEWAKE, ICL_TYPE_STRING,
2347 __FILE__, ICL_TYPE_INT32, __LINE__,
2348 ICL_TYPE_POINTER, tdc, ICL_TYPE_INT32,
2352 (struct tlocal1 *)osi_AllocLargeSpace(sizeof(struct tlocal1));
2353 setVcacheStatus = 0;
2356 * Remember if we are doing the reading from a replicated volume,
2357 * and how many times we've zipped around the fetch/analyze loop.
2359 fromReplica = (avc->f.states & CRO) ? 1 : 0;
2361 accP = &(afs_stats_cmfullperf.accessinf);
2363 (accP->replicatedRefs)++;
2365 (accP->unreplicatedRefs)++;
2366 #endif /* AFS_NOSTATS */
2367 /* this is a cache miss */
2368 afs_Trace4(afs_iclSetp, CM_TRACE_FETCHPROC, ICL_TYPE_POINTER, avc,
2369 ICL_TYPE_FID, &(avc->f.fid), ICL_TYPE_OFFSET,
2370 ICL_HANDLE_OFFSET(Position), ICL_TYPE_INT32, size);
2373 afs_stats_cmperf.dcacheMisses++;
2376 * Dynamic root support: fetch data from local memory.
2378 if (afs_IsDynroot(avc)) {
2382 afs_GetDynroot(&dynrootDir, &dynrootLen, &tsmall->OutStatus);
2384 dynrootDir += Position;
2385 dynrootLen -= Position;
2386 if (size > dynrootLen)
2390 code = afs_CFileWrite(file, 0, dynrootDir, size);
2398 tdc->validPos = Position + size;
2399 afs_CFileTruncate(file, size); /* prune it */
2400 } else if (afs_IsDynrootMount(avc)) {
2404 afs_GetDynrootMount(&dynrootDir, &dynrootLen, &tsmall->OutStatus);
2406 dynrootDir += Position;
2407 dynrootLen -= Position;
2408 if (size > dynrootLen)
2412 code = afs_CFileWrite(file, 0, dynrootDir, size);
2420 tdc->validPos = Position + size;
2421 afs_CFileTruncate(file, size); /* prune it */
2424 * Not a dynamic vnode: do the real fetch.
2429 * avc->lock(R) if setLocks && !slowPass
2430 * avc->lock(W) if !setLocks || slowPass
2434 tc = afs_Conn(&avc->f.fid, areq, SHARED_LOCK);
2436 afs_int32 length_hi, length, bytes;
2440 (accP->numReplicasAccessed)++;
2442 #endif /* AFS_NOSTATS */
2443 if (!setLocks || slowPass) {
2444 avc->callback = tc->srvr->server;
2446 newCallback = tc->srvr->server;
2451 tcall = rx_NewCall(tc->id);
2454 XSTATS_START_TIME(AFS_STATS_FS_RPCIDX_FETCHDATA);
2455 #ifdef AFS_64BIT_CLIENT
2456 length_hi = code = 0;
2457 if (!afs_serverHasNo64Bit(tc)) {
2461 StartRXAFS_FetchData64(tcall,
2462 (struct AFSFid *)&avc->f.fid.
2463 Fid, Position, tsize);
2466 afs_Trace2(afs_iclSetp, CM_TRACE_FETCH64CODE,
2467 ICL_TYPE_POINTER, avc, ICL_TYPE_INT32,
2471 rx_Read(tcall, (char *)&length_hi,
2474 if (bytes == sizeof(afs_int32)) {
2475 length_hi = ntohl(length_hi);
2478 code = rx_Error(tcall);
2480 code1 = rx_EndCall(tcall, code);
2482 tcall = (struct rx_call *)0;
2486 if (code == RXGEN_OPCODE || afs_serverHasNo64Bit(tc)) {
2487 if (Position > 0x7FFFFFFF) {
2494 tcall = rx_NewCall(tc->id);
2496 StartRXAFS_FetchData(tcall, (struct AFSFid *)
2497 &avc->f.fid.Fid, pos,
2501 afs_serverSetNo64Bit(tc);
2506 rx_Read(tcall, (char *)&length,
2509 if (bytes == sizeof(afs_int32)) {
2510 length = ntohl(length);
2512 code = rx_Error(tcall);
2515 FillInt64(lengthFound, length_hi, length);
2516 afs_Trace3(afs_iclSetp, CM_TRACE_FETCH64LENG,
2517 ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, code,
2519 ICL_HANDLE_OFFSET(lengthFound));
2520 #else /* AFS_64BIT_CLIENT */
2523 StartRXAFS_FetchData(tcall,
2524 (struct AFSFid *)&avc->f.fid.Fid,
2530 rx_Read(tcall, (char *)&length,
2533 if (bytes == sizeof(afs_int32)) {
2534 length = ntohl(length);
2536 code = rx_Error(tcall);
2539 #endif /* AFS_64BIT_CLIENT */
2544 &(afs_stats_cmfullperf.rpc.
2545 fsXferTimes[AFS_STATS_FS_XFERIDX_FETCHDATA]);
2546 osi_GetuTime(&xferStartTime);
2549 afs_CacheFetchProc(tcall, file,
2550 (afs_size_t) Position, tdc,
2552 &bytesXferred, length);
2554 osi_GetuTime(&xferStopTime);
2555 (xferP->numXfers)++;
2557 (xferP->numSuccesses)++;
2558 afs_stats_XferSumBytes
2559 [AFS_STATS_FS_XFERIDX_FETCHDATA] +=
2561 (xferP->sumBytes) +=
2562 (afs_stats_XferSumBytes
2563 [AFS_STATS_FS_XFERIDX_FETCHDATA] >> 10);
2564 afs_stats_XferSumBytes
2565 [AFS_STATS_FS_XFERIDX_FETCHDATA] &= 0x3FF;
2566 if (bytesXferred < xferP->minBytes)
2567 xferP->minBytes = bytesXferred;
2568 if (bytesXferred > xferP->maxBytes)
2569 xferP->maxBytes = bytesXferred;
2572 * Tally the size of the object. Note: we tally the actual size,
2573 * NOT the number of bytes that made it out over the wire.
2575 if (bytesToXfer <= AFS_STATS_MAXBYTES_BUCKET0)
2576 (xferP->count[0])++;
2577 else if (bytesToXfer <=
2578 AFS_STATS_MAXBYTES_BUCKET1)
2579 (xferP->count[1])++;
2580 else if (bytesToXfer <=
2581 AFS_STATS_MAXBYTES_BUCKET2)
2582 (xferP->count[2])++;
2583 else if (bytesToXfer <=
2584 AFS_STATS_MAXBYTES_BUCKET3)
2585 (xferP->count[3])++;
2586 else if (bytesToXfer <=
2587 AFS_STATS_MAXBYTES_BUCKET4)
2588 (xferP->count[4])++;
2589 else if (bytesToXfer <=
2590 AFS_STATS_MAXBYTES_BUCKET5)
2591 (xferP->count[5])++;
2592 else if (bytesToXfer <=
2593 AFS_STATS_MAXBYTES_BUCKET6)
2594 (xferP->count[6])++;
2595 else if (bytesToXfer <=
2596 AFS_STATS_MAXBYTES_BUCKET7)
2597 (xferP->count[7])++;
2599 (xferP->count[8])++;
2601 afs_stats_GetDiff(elapsedTime, xferStartTime,
2603 afs_stats_AddTo((xferP->sumTime), elapsedTime);
2604 afs_stats_SquareAddTo((xferP->sqrTime),
2606 if (afs_stats_TimeLessThan
2607 (elapsedTime, (xferP->minTime))) {
2608 afs_stats_TimeAssign((xferP->minTime),
2611 if (afs_stats_TimeGreaterThan
2612 (elapsedTime, (xferP->maxTime))) {
2613 afs_stats_TimeAssign((xferP->maxTime),
2619 afs_CacheFetchProc(tcall, file, Position, tdc,
2621 #endif /* AFS_NOSTATS */
2626 EndRXAFS_FetchData(tcall, &tsmall->OutStatus,
2634 code1 = rx_EndCall(tcall, code);
2643 /* callback could have been broken (or expired) in a race here,
2644 * but we return the data anyway. It's as good as we knew about
2645 * when we started. */
2647 * validPos is updated by CacheFetchProc, and can only be
2648 * modifed under a dcache write lock, which we've blocked out
2650 size = tdc->validPos - Position; /* actual segment size */
2653 afs_CFileTruncate(file, size); /* prune it */
2655 if (!setLocks || slowPass) {
2656 ObtainWriteLock(&afs_xcbhash, 453);
2657 afs_DequeueCallback(avc);
2658 avc->f.states &= ~(CStatd | CUnique);
2659 avc->callback = NULL;
2660 ReleaseWriteLock(&afs_xcbhash);
2661 if (avc->f.fid.Fid.Vnode & 1 || (vType(avc) == VDIR))
2662 osi_dnlc_purgedp(avc);
2664 /* Something lost. Forget about performance, and go
2665 * back with a vcache write lock.
2667 afs_CFileTruncate(file, 0);
2668 afs_AdjustSize(tdc, 0);
2669 afs_CFileClose(file);
2670 osi_FreeLargeSpace(tsmall);
2672 ReleaseWriteLock(&tdc->lock);
2675 ReleaseReadLock(&avc->lock);
2677 goto RetryGetDCache;
2681 } while (afs_Analyze
2682 (tc, code, &avc->f.fid, areq,
2683 AFS_STATS_FS_RPCIDX_FETCHDATA, SHARED_LOCK, NULL));
2687 * avc->lock(R) if setLocks && !slowPass
2688 * avc->lock(W) if !setLocks || slowPass
2694 * In the case of replicated access, jot down info on the number of
2695 * attempts it took before we got through or gave up.
2698 if (numFetchLoops <= 1)
2699 (accP->refFirstReplicaOK)++;
2700 if (numFetchLoops > accP->maxReplicasPerRef)
2701 accP->maxReplicasPerRef = numFetchLoops;
2703 #endif /* AFS_NOSTATS */
2705 tdc->dflags &= ~DFFetching;
2706 if (afs_osi_Wakeup(&tdc->validPos) == 0)
2707 afs_Trace4(afs_iclSetp, CM_TRACE_DCACHEWAKE, ICL_TYPE_STRING,
2708 __FILE__, ICL_TYPE_INT32, __LINE__, ICL_TYPE_POINTER,
2709 tdc, ICL_TYPE_INT32, tdc->dflags);
2710 if (avc->execsOrWriters == 0)
2711 tdc->f.states &= ~DWriting;
2713 /* now, if code != 0, we have an error and should punt.
2714 * note that we have the vcache write lock, either because
2715 * !setLocks or slowPass.
2718 afs_CFileTruncate(file, 0);
2719 afs_AdjustSize(tdc, 0);
2720 afs_CFileClose(file);
2721 ZapDCE(tdc); /* sets DFEntryMod */
2722 if (vType(avc) == VDIR) {
2725 tdc->f.states &= ~(DRO|DBackup|DRW);
2726 afs_DCMoveBucket(tdc, 0, 0);
2727 ReleaseWriteLock(&tdc->lock);
2729 if (!afs_IsDynroot(avc)) {
2730 ObtainWriteLock(&afs_xcbhash, 454);
2731 afs_DequeueCallback(avc);
2732 avc->f.states &= ~(CStatd | CUnique);
2733 ReleaseWriteLock(&afs_xcbhash);
2734 if (avc->f.fid.Fid.Vnode & 1 || (vType(avc) == VDIR))
2735 osi_dnlc_purgedp(avc);
2738 * avc->lock(W); assert(!setLocks || slowPass)
2740 osi_Assert(!setLocks || slowPass);
2742 tdc->f.states &= ~(DRO|DBackup|DRW);
2743 afs_DCMoveBucket(tdc, 0, 0);
2748 /* otherwise we copy in the just-fetched info */
2749 afs_CFileClose(file);
2750 afs_AdjustSize(tdc, size); /* new size */
2752 * Copy appropriate fields into vcache. Status is
2753 * copied later where we selectively acquire the
2754 * vcache write lock.
2757 afs_ProcessFS(avc, &tsmall->OutStatus, areq);
2759 setVcacheStatus = 1;
2760 hset64(tdc->f.versionNo, tsmall->OutStatus.dataVersionHigh,
2761 tsmall->OutStatus.DataVersion);
2762 tdc->dflags |= DFEntryMod;
2763 afs_indexFlags[tdc->index] |= IFEverUsed;
2764 ConvertWToSLock(&tdc->lock);
2765 } /*Data version numbers don't match */
2768 * Data version numbers match.
2770 afs_stats_cmperf.dcacheHits++;
2771 } /*Data version numbers match */
2773 updateV2DC(setLocks, avc, tdc, 335); /* set hint */
2777 * avc->lock(R) if setLocks && !slowPass
2778 * avc->lock(W) if !setLocks || slowPass
2779 * tdc->lock(S) if tdc
2783 * See if this was a reference to a file in the local cell.
2785 if (afs_IsPrimaryCellNum(avc->f.fid.Cell))
2786 afs_stats_cmperf.dlocalAccesses++;
2788 afs_stats_cmperf.dremoteAccesses++;
2790 /* Fix up LRU info */
2793 MObtainWriteLock(&afs_xdcache, 602);
2794 hset(afs_indexTimes[tdc->index], afs_indexCounter);
2795 hadd32(afs_indexCounter, 1);
2796 MReleaseWriteLock(&afs_xdcache);
2798 /* return the data */
2799 if (vType(avc) == VDIR)
2802 *aoffset = AFS_CHUNKOFFSET(abyte);
2803 *alen = (tdc->f.chunkBytes - *aoffset);
2804 ReleaseSharedLock(&tdc->lock);
2809 * avc->lock(R) if setLocks && !slowPass
2810 * avc->lock(W) if !setLocks || slowPass
2813 /* Fix up the callback and status values in the vcache */
2815 if (setLocks && !slowPass) {
2818 * This is our dirty little secret to parallel fetches.
2819 * We don't write-lock the vcache while doing the fetch,
2820 * but potentially we'll need to update the vcache after
2821 * the fetch is done.
2823 * Drop the read lock and try to re-obtain the write
2824 * lock. If the vcache still has the same DV, it's
2825 * ok to go ahead and install the new data.
2827 afs_hyper_t currentDV, statusDV;
2829 hset(currentDV, avc->f.m.DataVersion);
2831 if (setNewCallback && avc->callback != newCallback)
2835 hset64(statusDV, tsmall->OutStatus.dataVersionHigh,
2836 tsmall->OutStatus.DataVersion);
2838 if (setVcacheStatus && avc->f.m.Length != tsmall->OutStatus.Length)
2840 if (setVcacheStatus && !hsame(currentDV, statusDV))
2844 ReleaseReadLock(&avc->lock);
2846 if (doVcacheUpdate) {
2847 ObtainWriteLock(&avc->lock, 615);
2848 if (!hsame(avc->f.m.DataVersion, currentDV)) {
2849 /* We lose. Someone will beat us to it. */
2851 ReleaseWriteLock(&avc->lock);
2856 /* With slow pass, we've already done all the updates */
2858 ReleaseWriteLock(&avc->lock);
2861 /* Check if we need to perform any last-minute fixes with a write-lock */
2862 if (!setLocks || doVcacheUpdate) {
2864 avc->callback = newCallback;
2865 if (tsmall && setVcacheStatus)
2866 afs_ProcessFS(avc, &tsmall->OutStatus, areq);
2868 ReleaseWriteLock(&avc->lock);
2872 osi_FreeLargeSpace(tsmall);
2875 } /*afs_GetDCache */
2879 * afs_WriteThroughDSlots
2882 * Sweep through the dcache slots and write out any modified
2883 * in-memory data back on to our caching store.
2889 * The afs_xdcache is write-locked through this whole affair.
2892 afs_WriteThroughDSlots(void)
2894 register struct dcache *tdc;
2895 register afs_int32 i, touchedit = 0;
2897 struct afs_q DirtyQ, *tq;
2899 AFS_STATCNT(afs_WriteThroughDSlots);
2902 * Because of lock ordering, we can't grab dcache locks while
2903 * holding afs_xdcache. So we enter xdcache, get a reference
2904 * for every dcache entry, and exit xdcache.
2906 MObtainWriteLock(&afs_xdcache, 283);
2908 for (i = 0; i < afs_cacheFiles; i++) {
2909 tdc = afs_indexTable[i];
2911 /* Grab tlock in case the existing refcount isn't zero */
2912 if (tdc && !(afs_indexFlags[i] & (IFFree | IFDiscarded))) {
2913 ObtainWriteLock(&tdc->tlock, 623);
2915 ReleaseWriteLock(&tdc->tlock);
2917 QAdd(&DirtyQ, &tdc->dirty);
2920 MReleaseWriteLock(&afs_xdcache);
2923 * Now, for each dcache entry we found, check if it's dirty.
2924 * If so, get write-lock, get afs_xdcache, which protects
2925 * afs_cacheInodep, and flush it. Don't forget to put back
2929 #define DQTODC(q) ((struct dcache *)(((char *) (q)) - sizeof(struct afs_q)))
2931 for (tq = DirtyQ.prev; tq != &DirtyQ; tq = QPrev(tq)) {
2933 if (tdc->dflags & DFEntryMod) {
2936 wrLock = (0 == NBObtainWriteLock(&tdc->lock, 619));
2938 /* Now that we have the write lock, double-check */
2939 if (wrLock && (tdc->dflags & DFEntryMod)) {
2940 tdc->dflags &= ~DFEntryMod;
2941 MObtainWriteLock(&afs_xdcache, 620);
2942 afs_WriteDCache(tdc, 1);
2943 MReleaseWriteLock(&afs_xdcache);
2947 ReleaseWriteLock(&tdc->lock);
2953 MObtainWriteLock(&afs_xdcache, 617);
2954 if (!touchedit && (cacheDiskType != AFS_FCACHE_TYPE_MEM)) {
2955 /* Touch the file to make sure that the mtime on the file is kept
2956 * up-to-date to avoid losing cached files on cold starts because
2957 * their mtime seems old...
2959 struct afs_fheader theader;
2961 theader.magic = AFS_FHMAGIC;
2962 theader.firstCSize = AFS_FIRSTCSIZE;
2963 theader.otherCSize = AFS_OTHERCSIZE;
2964 theader.version = AFS_CI_VERSION;
2965 afs_osi_Write(afs_cacheInodep, 0, &theader, sizeof(theader));
2967 MReleaseWriteLock(&afs_xdcache);
2974 * Return a pointer to an freshly initialized dcache entry using
2975 * a memory-based cache. The tlock will be read-locked.
2978 * aslot : Dcache slot to look at.
2979 * tmpdc : Ptr to dcache entry.
2982 * Must be called with afs_xdcache write-locked.
2986 afs_MemGetDSlot(register afs_int32 aslot, register struct dcache *tmpdc)
2988 register struct dcache *tdc;
2991 AFS_STATCNT(afs_MemGetDSlot);
2992 if (CheckLock(&afs_xdcache) != -1)
2993 osi_Panic("getdslot nolock");
2994 if (aslot < 0 || aslot >= afs_cacheFiles)
2995 osi_Panic("getdslot slot %d (of %d)", aslot, afs_cacheFiles);
2996 tdc = afs_indexTable[aslot];
2998 QRemove(&tdc->lruq); /* move to queue head */
2999 QAdd(&afs_DLRU, &tdc->lruq);
3000 /* We're holding afs_xdcache, but get tlock in case refCount != 0 */
3001 ObtainWriteLock(&tdc->tlock, 624);
3003 ConvertWToRLock(&tdc->tlock);
3006 if (tmpdc == NULL) {
3007 if (!afs_freeDSList)
3008 afs_GetDownDSlot(4);
3009 if (!afs_freeDSList) {
3010 /* none free, making one is better than a panic */
3011 afs_stats_cmperf.dcacheXAllocs++; /* count in case we have a leak */
3012 tdc = (struct dcache *)afs_osi_Alloc(sizeof(struct dcache));
3013 #ifdef KERNEL_HAVE_PIN
3014 pin((char *)tdc, sizeof(struct dcache)); /* XXX */
3017 tdc = afs_freeDSList;
3018 afs_freeDSList = (struct dcache *)tdc->lruq.next;
3021 tdc->dflags = 0; /* up-to-date, not in free q */
3023 QAdd(&afs_DLRU, &tdc->lruq);
3024 if (tdc->lruq.prev == &tdc->lruq)
3025 osi_Panic("lruq 3");
3031 /* initialize entry */
3032 tdc->f.fid.Cell = 0;
3033 tdc->f.fid.Fid.Volume = 0;
3035 hones(tdc->f.versionNo);
3036 tdc->f.inode.mem = aslot;
3037 tdc->dflags |= DFEntryMod;
3040 afs_indexUnique[aslot] = tdc->f.fid.Fid.Unique;
3043 osi_Assert(0 == NBObtainWriteLock(&tdc->lock, 674));
3044 osi_Assert(0 == NBObtainWriteLock(&tdc->mflock, 675));
3045 osi_Assert(0 == NBObtainWriteLock(&tdc->tlock, 676));
3048 AFS_RWLOCK_INIT(&tdc->lock, "dcache lock");
3049 AFS_RWLOCK_INIT(&tdc->tlock, "dcache tlock");
3050 AFS_RWLOCK_INIT(&tdc->mflock, "dcache flock");
3051 ObtainReadLock(&tdc->tlock);
3054 afs_indexTable[aslot] = tdc;
3057 } /*afs_MemGetDSlot */
3059 unsigned int last_error = 0, lasterrtime = 0;
3065 * Return a pointer to an freshly initialized dcache entry using
3066 * a UFS-based disk cache. The dcache tlock will be read-locked.
3069 * aslot : Dcache slot to look at.
3070 * tmpdc : Ptr to dcache entry.
3073 * afs_xdcache lock write-locked.
3076 afs_UFSGetDSlot(register afs_int32 aslot, register struct dcache *tmpdc)
3078 register afs_int32 code;
3079 register struct dcache *tdc;
3083 AFS_STATCNT(afs_UFSGetDSlot);
3084 if (CheckLock(&afs_xdcache) != -1)
3085 osi_Panic("getdslot nolock");
3086 if (aslot < 0 || aslot >= afs_cacheFiles)
3087 osi_Panic("getdslot slot %d (of %d)", aslot, afs_cacheFiles);
3088 tdc = afs_indexTable[aslot];
3090 QRemove(&tdc->lruq); /* move to queue head */
3091 QAdd(&afs_DLRU, &tdc->lruq);
3092 /* Grab tlock in case refCount != 0 */
3093 ObtainWriteLock(&tdc->tlock, 625);
3095 ConvertWToRLock(&tdc->tlock);
3098 /* otherwise we should read it in from the cache file */
3100 * If we weren't passed an in-memory region to place the file info,
3101 * we have to allocate one.
3103 if (tmpdc == NULL) {
3104 if (!afs_freeDSList)
3105 afs_GetDownDSlot(4);
3106 if (!afs_freeDSList) {
3107 /* none free, making one is better than a panic */
3108 afs_stats_cmperf.dcacheXAllocs++; /* count in case we have a leak */
3109 tdc = (struct dcache *)afs_osi_Alloc(sizeof(struct dcache));
3110 #ifdef KERNEL_HAVE_PIN
3111 pin((char *)tdc, sizeof(struct dcache)); /* XXX */
3114 tdc = afs_freeDSList;
3115 afs_freeDSList = (struct dcache *)tdc->lruq.next;
3118 tdc->dflags = 0; /* up-to-date, not in free q */
3120 QAdd(&afs_DLRU, &tdc->lruq);
3121 if (tdc->lruq.prev == &tdc->lruq)
3122 osi_Panic("lruq 3");
3129 * Seek to the aslot'th entry and read it in.
3132 afs_osi_Read(afs_cacheInodep,
3133 sizeof(struct fcache) * aslot +
3134 sizeof(struct afs_fheader), (char *)(&tdc->f),
3135 sizeof(struct fcache));
3137 if (code != sizeof(struct fcache))
3139 if (!afs_CellNumValid(tdc->f.fid.Cell))
3143 tdc->f.fid.Cell = 0;
3144 tdc->f.fid.Fid.Volume = 0;
3146 hones(tdc->f.versionNo);
3147 tdc->dflags |= DFEntryMod;
3148 #if defined(KERNEL_HAVE_UERROR)
3149 last_error = getuerror();
3151 lasterrtime = osi_Time();
3152 afs_indexUnique[aslot] = tdc->f.fid.Fid.Unique;
3153 tdc->f.states &= ~(DRO|DBackup|DRW);
3154 afs_DCMoveBucket(tdc, 0, 0);
3157 if (tdc->f.states & DRO) {
3158 afs_DCMoveBucket(tdc, 0, 2);
3159 } else if (tdc->f.states & DBackup) {
3160 afs_DCMoveBucket(tdc, 0, 1);
3162 afs_DCMoveBucket(tdc, 0, 1);
3168 if (tdc->f.chunk >= 0)
3169 tdc->validPos = AFS_CHUNKTOBASE(tdc->f.chunk) + tdc->f.chunkBytes;
3174 osi_Assert(0 == NBObtainWriteLock(&tdc->lock, 674));
3175 osi_Assert(0 == NBObtainWriteLock(&tdc->mflock, 675));
3176 osi_Assert(0 == NBObtainWriteLock(&tdc->tlock, 676));
3179 AFS_RWLOCK_INIT(&tdc->lock, "dcache lock");
3180 AFS_RWLOCK_INIT(&tdc->tlock, "dcache tlock");
3181 AFS_RWLOCK_INIT(&tdc->mflock, "dcache flock");
3182 ObtainReadLock(&tdc->tlock);
3185 * If we didn't read into a temporary dcache region, update the
3186 * slot pointer table.
3189 afs_indexTable[aslot] = tdc;
3192 } /*afs_UFSGetDSlot */
3197 * Write a particular dcache entry back to its home in the
3200 * \param adc Pointer to the dcache entry to write.
3201 * \param atime If true, set the modtime on the file to the current time.
3203 * \note Environment:
3204 * Must be called with the afs_xdcache lock at least read-locked,
3205 * and dcache entry at least read-locked.
3206 * The reference count is not changed.
3210 afs_WriteDCache(register struct dcache *adc, int atime)
3212 register afs_int32 code;
3214 if (cacheDiskType == AFS_FCACHE_TYPE_MEM)
3216 AFS_STATCNT(afs_WriteDCache);
3217 osi_Assert(WriteLocked(&afs_xdcache));
3219 adc->f.modTime = osi_Time();
3221 * Seek to the right dcache slot and write the in-memory image out to disk.
3223 afs_cellname_write();
3225 afs_osi_Write(afs_cacheInodep,
3226 sizeof(struct fcache) * adc->index +
3227 sizeof(struct afs_fheader), (char *)(&adc->f),
3228 sizeof(struct fcache));
3229 if (code != sizeof(struct fcache))
3237 * Wake up users of a particular file waiting for stores to take
3240 * \param avc Ptr to related vcache entry.
3242 * \note Environment:
3243 * Nothing interesting.
3246 afs_wakeup(register struct vcache *avc)
3249 register struct brequest *tb;
3251 AFS_STATCNT(afs_wakeup);
3252 for (i = 0; i < NBRS; i++, tb++) {
3253 /* if request is valid and for this file, we've found it */
3254 if (tb->refCount > 0 && avc == tb->vc) {
3257 * If CSafeStore is on, then we don't awaken the guy
3258 * waiting for the store until the whole store has finished.
3259 * Otherwise, we do it now. Note that if CSafeStore is on,
3260 * the BStore routine actually wakes up the user, instead
3262 * I think this is redundant now because this sort of thing
3263 * is already being handled by the higher-level code.
3265 if ((avc->f.states & CSafeStore) == 0) {
3267 tb->flags |= BUVALID;
3268 if (tb->flags & BUWAIT) {
3269 tb->flags &= ~BUWAIT;
3281 * Given a file name and inode, set up that file to be an
3282 * active member in the AFS cache. This also involves checking
3283 * the usability of its data.
3285 * \param afile Name of the cache file to initialize.
3286 * \param ainode Inode of the file.
3288 * \note Environment:
3289 * This function is called only during initialization.
3292 afs_InitCacheFile(char *afile, ino_t ainode)
3294 register afs_int32 code;
3297 struct osi_file *tfile;
3298 struct osi_stat tstat;
3299 register struct dcache *tdc;
3301 AFS_STATCNT(afs_InitCacheFile);
3302 index = afs_stats_cmperf.cacheNumEntries;
3303 if (index >= afs_cacheFiles)
3306 MObtainWriteLock(&afs_xdcache, 282);
3307 tdc = afs_GetDSlot(index, NULL);
3308 ReleaseReadLock(&tdc->tlock);
3309 MReleaseWriteLock(&afs_xdcache);
3311 ObtainWriteLock(&tdc->lock, 621);
3312 MObtainWriteLock(&afs_xdcache, 622);
3314 code = afs_LookupInodeByPath(afile, &tdc->f.inode.ufs, NULL);
3316 ReleaseWriteLock(&afs_xdcache);
3317 ReleaseWriteLock(&tdc->lock);
3322 /* Add any other 'complex' inode types here ... */
3323 #if defined(UKERNEL) || !defined(LINUX_USE_FH)
3324 tdc->f.inode.ufs = ainode;
3326 osi_Panic("Can't init cache with inode numbers when complex inodes are "
3331 if ((tdc->f.states & DWriting) || tdc->f.fid.Fid.Volume == 0)
3333 tfile = osi_UFSOpen(&tdc->f.inode);
3334 code = afs_osi_Stat(tfile, &tstat);
3336 osi_Panic("initcachefile stat");
3339 * If file size doesn't match the cache info file, it's probably bad.
3341 if (tdc->f.chunkBytes != tstat.size)
3343 tdc->f.chunkBytes = 0;
3346 * If file changed within T (120?) seconds of cache info file, it's
3347 * probably bad. In addition, if slot changed within last T seconds,
3348 * the cache info file may be incorrectly identified, and so slot
3351 if (cacheInfoModTime < tstat.mtime + 120)
3353 if (cacheInfoModTime < tdc->f.modTime + 120)
3355 /* In case write through is behind, make sure cache items entry is
3356 * at least as new as the chunk.
3358 if (tdc->f.modTime < tstat.mtime)
3361 tdc->f.fid.Fid.Volume = 0; /* not in the hash table */
3362 if (tstat.size != 0)
3363 osi_UFSTruncate(tfile, 0);
3364 tdc->f.states &= ~(DRO|DBackup|DRW);
3365 afs_DCMoveBucket(tdc, 0, 0);
3366 /* put entry in free cache slot list */
3367 afs_dvnextTbl[tdc->index] = afs_freeDCList;
3368 afs_freeDCList = index;
3370 afs_indexFlags[index] |= IFFree;
3371 afs_indexUnique[index] = 0;
3374 * We must put this entry in the appropriate hash tables.
3375 * Note that i is still set from the above DCHash call
3377 code = DCHash(&tdc->f.fid, tdc->f.chunk);
3378 afs_dcnextTbl[tdc->index] = afs_dchashTbl[code];
3379 afs_dchashTbl[code] = tdc->index;
3380 code = DVHash(&tdc->f.fid);
3381 afs_dvnextTbl[tdc->index] = afs_dvhashTbl[code];
3382 afs_dvhashTbl[code] = tdc->index;
3383 afs_AdjustSize(tdc, tstat.size); /* adjust to new size */
3385 /* has nontrivial amt of data */
3386 afs_indexFlags[index] |= IFEverUsed;
3387 afs_stats_cmperf.cacheFilesReused++;
3389 * Initialize index times to file's mod times; init indexCounter
3392 hset32(afs_indexTimes[index], tstat.atime);
3393 if (hgetlo(afs_indexCounter) < tstat.atime) {
3394 hset32(afs_indexCounter, tstat.atime);
3396 afs_indexUnique[index] = tdc->f.fid.Fid.Unique;
3397 } /*File is not bad */
3399 osi_UFSClose(tfile);
3400 tdc->f.states &= ~DWriting;
3401 tdc->dflags &= ~DFEntryMod;
3402 /* don't set f.modTime; we're just cleaning up */
3403 afs_WriteDCache(tdc, 0);
3404 ReleaseWriteLock(&afs_xdcache);
3405 ReleaseWriteLock(&tdc->lock);
3407 afs_stats_cmperf.cacheNumEntries++;
3412 /*Max # of struct dcache's resident at any time*/
3414 * If 'dchint' is enabled then in-memory dcache min is increased because of
3420 * Initialize dcache related variables.
3430 afs_dcacheInit(int afiles, int ablocks, int aDentries, int achunk, int aflags)
3432 register struct dcache *tdp;
3436 afs_freeDCList = NULLIDX;
3437 afs_discardDCList = NULLIDX;
3438 afs_freeDCCount = 0;
3439 afs_freeDSList = NULL;
3440 hzero(afs_indexCounter);
3442 LOCK_INIT(&afs_xdcache, "afs_xdcache");
3448 if (achunk < 0 || achunk > 30)
3449 achunk = 13; /* Use default */
3450 AFS_SETCHUNKSIZE(achunk);
3456 if (aflags & AFSCALL_INIT_MEMCACHE) {
3458 * Use a memory cache instead of a disk cache
3460 cacheDiskType = AFS_FCACHE_TYPE_MEM;
3461 afs_cacheType = &afs_MemCacheOps;
3462 afiles = (afiles < aDentries) ? afiles : aDentries; /* min */
3463 ablocks = afiles * (AFS_FIRSTCSIZE / 1024);
3464 /* ablocks is reported in 1K blocks */
3465 code = afs_InitMemCache(afiles, AFS_FIRSTCSIZE, aflags);
3467 printf("afsd: memory cache too large for available memory.\n");
3468 printf("afsd: AFS files cannot be accessed.\n\n");
3470 afiles = ablocks = 0;
3472 printf("Memory cache: Allocating %d dcache entries...",
3475 cacheDiskType = AFS_FCACHE_TYPE_UFS;
3476 afs_cacheType = &afs_UfsCacheOps;
3479 if (aDentries > 512)
3480 afs_dhashsize = 2048;
3481 /* initialize hash tables */
3483 (afs_int32 *) afs_osi_Alloc(afs_dhashsize * sizeof(afs_int32));
3485 (afs_int32 *) afs_osi_Alloc(afs_dhashsize * sizeof(afs_int32));
3486 for (i = 0; i < afs_dhashsize; i++) {
3487 afs_dvhashTbl[i] = NULLIDX;
3488 afs_dchashTbl[i] = NULLIDX;
3490 afs_dvnextTbl = (afs_int32 *) afs_osi_Alloc(afiles * sizeof(afs_int32));
3491 afs_dcnextTbl = (afs_int32 *) afs_osi_Alloc(afiles * sizeof(afs_int32));
3492 for (i = 0; i < afiles; i++) {
3493 afs_dvnextTbl[i] = NULLIDX;
3494 afs_dcnextTbl[i] = NULLIDX;
3497 /* Allocate and zero the pointer array to the dcache entries */
3498 afs_indexTable = (struct dcache **)
3499 afs_osi_Alloc(sizeof(struct dcache *) * afiles);
3500 memset((char *)afs_indexTable, 0, sizeof(struct dcache *) * afiles);
3502 (afs_hyper_t *) afs_osi_Alloc(afiles * sizeof(afs_hyper_t));
3503 memset((char *)afs_indexTimes, 0, afiles * sizeof(afs_hyper_t));
3505 (afs_int32 *) afs_osi_Alloc(afiles * sizeof(afs_uint32));
3506 memset((char *)afs_indexUnique, 0, afiles * sizeof(afs_uint32));
3507 afs_indexFlags = (u_char *) afs_osi_Alloc(afiles * sizeof(u_char));
3508 memset((char *)afs_indexFlags, 0, afiles * sizeof(char));
3510 /* Allocate and thread the struct dcache entries themselves */
3511 tdp = afs_Initial_freeDSList =
3512 (struct dcache *)afs_osi_Alloc(aDentries * sizeof(struct dcache));
3513 memset((char *)tdp, 0, aDentries * sizeof(struct dcache));
3514 #ifdef KERNEL_HAVE_PIN
3515 pin((char *)afs_indexTable, sizeof(struct dcache *) * afiles); /* XXX */
3516 pin((char *)afs_indexTimes, sizeof(afs_hyper_t) * afiles); /* XXX */
3517 pin((char *)afs_indexFlags, sizeof(char) * afiles); /* XXX */
3518 pin((char *)afs_indexUnique, sizeof(afs_int32) * afiles); /* XXX */
3519 pin((char *)tdp, aDentries * sizeof(struct dcache)); /* XXX */
3520 pin((char *)afs_dvhashTbl, sizeof(afs_int32) * afs_dhashsize); /* XXX */
3521 pin((char *)afs_dchashTbl, sizeof(afs_int32) * afs_dhashsize); /* XXX */
3522 pin((char *)afs_dcnextTbl, sizeof(afs_int32) * afiles); /* XXX */
3523 pin((char *)afs_dvnextTbl, sizeof(afs_int32) * afiles); /* XXX */
3526 afs_freeDSList = &tdp[0];
3527 for (i = 0; i < aDentries - 1; i++) {
3528 tdp[i].lruq.next = (struct afs_q *)(&tdp[i + 1]);
3529 AFS_RWLOCK_INIT(&tdp[i].lock, "dcache lock");
3530 AFS_RWLOCK_INIT(&tdp[i].tlock, "dcache tlock");
3531 AFS_RWLOCK_INIT(&tdp[i].mflock, "dcache flock");
3533 tdp[aDentries - 1].lruq.next = (struct afs_q *)0;
3534 AFS_RWLOCK_INIT(&tdp[aDentries - 1].lock, "dcache lock");
3535 AFS_RWLOCK_INIT(&tdp[aDentries - 1].tlock, "dcache tlock");
3536 AFS_RWLOCK_INIT(&tdp[aDentries - 1].mflock, "dcache flock");
3538 afs_stats_cmperf.cacheBlocksOrig = afs_stats_cmperf.cacheBlocksTotal =
3539 afs_cacheBlocks = ablocks;
3540 afs_ComputeCacheParms(); /* compute parms based on cache size */
3542 afs_dcentries = aDentries;
3544 afs_stats_cmperf.cacheBucket0_Discarded =
3545 afs_stats_cmperf.cacheBucket1_Discarded =
3546 afs_stats_cmperf.cacheBucket2_Discarded = 0;
3552 * Shuts down the cache.
3556 shutdown_dcache(void)
3560 afs_osi_Free(afs_dvnextTbl, afs_cacheFiles * sizeof(afs_int32));
3561 afs_osi_Free(afs_dcnextTbl, afs_cacheFiles * sizeof(afs_int32));
3562 afs_osi_Free(afs_indexTable, afs_cacheFiles * sizeof(struct dcache *));
3563 afs_osi_Free(afs_indexTimes, afs_cacheFiles * sizeof(afs_hyper_t));
3564 afs_osi_Free(afs_indexUnique, afs_cacheFiles * sizeof(afs_uint32));
3565 afs_osi_Free(afs_indexFlags, afs_cacheFiles * sizeof(u_char));
3566 afs_osi_Free(afs_Initial_freeDSList,
3567 afs_dcentries * sizeof(struct dcache));
3568 #ifdef KERNEL_HAVE_PIN
3569 unpin((char *)afs_dcnextTbl, afs_cacheFiles * sizeof(afs_int32));
3570 unpin((char *)afs_dvnextTbl, afs_cacheFiles * sizeof(afs_int32));
3571 unpin((char *)afs_indexTable, afs_cacheFiles * sizeof(struct dcache *));
3572 unpin((char *)afs_indexTimes, afs_cacheFiles * sizeof(afs_hyper_t));
3573 unpin((char *)afs_indexUnique, afs_cacheFiles * sizeof(afs_uint32));
3574 unpin((u_char *) afs_indexFlags, afs_cacheFiles * sizeof(u_char));
3575 unpin(afs_Initial_freeDSList, afs_dcentries * sizeof(struct dcache));
3579 for (i = 0; i < afs_dhashsize; i++) {
3580 afs_dvhashTbl[i] = NULLIDX;
3581 afs_dchashTbl[i] = NULLIDX;
3584 afs_osi_Free(afs_dvhashTbl, afs_dhashsize * sizeof(afs_int32));
3585 afs_osi_Free(afs_dchashTbl, afs_dhashsize * sizeof(afs_int32));
3587 afs_blocksUsed = afs_dcentries = 0;
3588 afs_stats_cmperf.cacheBucket0_Discarded =
3589 afs_stats_cmperf.cacheBucket1_Discarded =
3590 afs_stats_cmperf.cacheBucket2_Discarded = 0;
3591 hzero(afs_indexCounter);
3593 afs_freeDCCount = 0;
3594 afs_freeDCList = NULLIDX;
3595 afs_discardDCList = NULLIDX;
3596 afs_freeDSList = afs_Initial_freeDSList = 0;
3598 LOCK_INIT(&afs_xdcache, "afs_xdcache");
3604 * Get a dcache ready for writing, respecting the current cache size limits
3606 * len is required because afs_GetDCache with flag == 4 expects the length
3607 * field to be filled. It decides from this whether it's necessary to fetch
3608 * data into the chunk before writing or not (when the whole chunk is
3611 * \param avc The vcache to fetch a dcache for
3612 * \param filePos The start of the section to be written
3613 * \param len The length of the section to be written
3617 * \return If successful, a reference counted dcache with tdc->lock held. Lock
3618 * must be released and afs_PutDCache() called to free dcache.
3621 * \note avc->lock must be held on entry. Function may release and reobtain
3622 * avc->lock and GLOCK.
3626 afs_ObtainDCacheForWriting(struct vcache *avc, afs_size_t filePos,
3627 afs_size_t len, struct vrequest *areq,
3629 struct dcache *tdc = NULL;
3632 /* read the cached info */
3634 tdc = afs_FindDCache(avc, filePos);
3636 ObtainWriteLock(&tdc->lock, 657);
3637 } else if (afs_blocksUsed >
3638 PERCENT(CM_WAITFORDRAINPCT, afs_cacheBlocks)) {
3639 tdc = afs_FindDCache(avc, filePos);
3641 ObtainWriteLock(&tdc->lock, 658);
3642 if (!hsame(tdc->f.versionNo, avc->f.m.DataVersion)
3643 || (tdc->dflags & DFFetching)) {
3644 ReleaseWriteLock(&tdc->lock);
3650 afs_MaybeWakeupTruncateDaemon();
3651 while (afs_blocksUsed >
3652 PERCENT(CM_WAITFORDRAINPCT, afs_cacheBlocks)) {
3653 ReleaseWriteLock(&avc->lock);
3654 if (afs_blocksUsed - afs_blocksDiscarded >
3655 PERCENT(CM_WAITFORDRAINPCT, afs_cacheBlocks)) {
3656 afs_WaitForCacheDrain = 1;
3657 afs_osi_Sleep(&afs_WaitForCacheDrain);
3659 afs_MaybeFreeDiscardedDCache();
3660 afs_MaybeWakeupTruncateDaemon();
3661 ObtainWriteLock(&avc->lock, 509);
3663 avc->f.states |= CDirty;
3664 tdc = afs_GetDCache(avc, filePos, areq, &offset, &len, 4);
3666 ObtainWriteLock(&tdc->lock, 659);
3669 tdc = afs_GetDCache(avc, filePos, areq, &offset, &len, 4);
3671 ObtainWriteLock(&tdc->lock, 660);
3674 if (!(afs_indexFlags[tdc->index] & IFDataMod)) {
3675 afs_stats_cmperf.cacheCurrDirtyChunks++;
3676 afs_indexFlags[tdc->index] |= IFDataMod; /* so it doesn't disappear */
3678 if (!(tdc->f.states & DWriting)) {
3679 /* don't mark entry as mod if we don't have to */
3680 tdc->f.states |= DWriting;
3681 tdc->dflags |= DFEntryMod;
3687 #if defined(AFS_DISCON_ENV)
3690 * Make a shadow copy of a dir's dcache. It's used for disconnected
3691 * operations like remove/create/rename to keep the original directory data.
3692 * On reconnection, we can diff the original data with the server and get the
3693 * server changes and with the local data to get the local changes.
3695 * \param avc The dir vnode.
3696 * \param adc The dir dcache.
3698 * \return 0 for success.
3700 * \note The vcache entry must be write locked.
3701 * \note The dcache entry must be read locked.
3703 int afs_MakeShadowDir(struct vcache *avc, struct dcache *adc)
3705 int i, code, ret_code = 0, written, trans_size;
3706 struct dcache *new_dc = NULL;
3707 struct osi_file *tfile_src, *tfile_dst;
3708 struct VenusFid shadow_fid;
3712 /* Is this a dir? */
3713 if (vType(avc) != VDIR)
3716 if (avc->f.shadow.vnode || avc->f.shadow.unique)
3719 /* Generate a fid for the shadow dir. */
3720 shadow_fid.Cell = avc->f.fid.Cell;
3721 shadow_fid.Fid.Volume = avc->f.fid.Fid.Volume;
3722 afs_GenShadowFid(&shadow_fid);
3724 ObtainWriteLock(&afs_xdcache, 716);
3726 /* Get a fresh dcache. */
3727 new_dc = afs_AllocDCache(avc, 0, 0, &shadow_fid);
3729 ObtainReadLock(&adc->mflock);
3731 /* Set up the new fid. */
3732 /* Copy interesting data from original dir dcache. */
3733 new_dc->mflags = adc->mflags;
3734 new_dc->dflags = adc->dflags;
3735 new_dc->f.modTime = adc->f.modTime;
3736 new_dc->f.versionNo = adc->f.versionNo;
3737 new_dc->f.states = adc->f.states;
3738 new_dc->f.chunk= adc->f.chunk;
3739 new_dc->f.chunkBytes = adc->f.chunkBytes;
3741 ReleaseReadLock(&adc->mflock);
3743 /* Now add to the two hash chains */
3744 i = DCHash(&shadow_fid, 0);
3745 afs_dcnextTbl[new_dc->index] = afs_dchashTbl[i];
3746 afs_dchashTbl[i] = new_dc->index;
3748 i = DVHash(&shadow_fid);
3749 afs_dvnextTbl[new_dc->index] = afs_dvhashTbl[i];
3750 afs_dvhashTbl[i] = new_dc->index;
3752 ReleaseWriteLock(&afs_xdcache);
3754 /* Alloc a 4k block. */
3755 data = (char *) afs_osi_Alloc(4096);
3757 printf("afs_MakeShadowDir: could not alloc data\n");
3762 /* Open the files. */
3763 tfile_src = afs_CFileOpen(&adc->f.inode);
3764 tfile_dst = afs_CFileOpen(&new_dc->f.inode);
3766 /* And now copy dir dcache data into this dcache,
3770 while (written < adc->f.chunkBytes) {
3771 trans_size = adc->f.chunkBytes - written;
3772 if (trans_size > 4096)
3775 /* Read a chunk from the dcache. */
3776 code = afs_CFileRead(tfile_src, written, data, trans_size);
3777 if (code < trans_size) {
3782 /* Write it to the new dcache. */
3783 code = afs_CFileWrite(tfile_dst, written, data, trans_size);
3784 if (code < trans_size) {
3789 written+=trans_size;
3792 afs_CFileClose(tfile_dst);
3793 afs_CFileClose(tfile_src);
3795 afs_osi_Free(data, 4096);
3797 ReleaseWriteLock(&new_dc->lock);
3798 afs_PutDCache(new_dc);
3801 ObtainWriteLock(&afs_xvcache, 763);
3802 ObtainWriteLock(&afs_disconDirtyLock, 765);
3803 QAdd(&afs_disconShadow, &avc->shadowq);
3805 ReleaseWriteLock(&afs_disconDirtyLock);
3806 ReleaseWriteLock(&afs_xvcache);
3808 avc->f.shadow.vnode = shadow_fid.Fid.Vnode;
3809 avc->f.shadow.unique = shadow_fid.Fid.Unique;
3817 * Delete the dcaches of a shadow dir.
3819 * \param avc The vcache containing the shadow fid.
3821 * \note avc must be write locked.
3823 void afs_DeleteShadowDir(struct vcache *avc)
3826 struct VenusFid shadow_fid;
3828 shadow_fid.Cell = avc->f.fid.Cell;
3829 shadow_fid.Fid.Volume = avc->f.fid.Fid.Volume;
3830 shadow_fid.Fid.Vnode = avc->f.shadow.vnode;
3831 shadow_fid.Fid.Unique = avc->f.shadow.unique;
3833 tdc = afs_FindDCacheByFid(&shadow_fid);
3835 afs_HashOutDCache(tdc, 1);
3836 afs_DiscardDCache(tdc);
3839 avc->f.shadow.vnode = avc->f.shadow.unique = 0;
3840 ObtainWriteLock(&afs_disconDirtyLock, 708);
3841 QRemove(&avc->shadowq);
3842 ReleaseWriteLock(&afs_disconDirtyLock);
3843 afs_PutVCache(avc); /* Because we held it when we added to the queue */
3847 * Populate a dcache with empty chunks up to a given file size,
3848 * used before extending a file in order to avoid 'holes' which
3849 * we can't access in disconnected mode.
3851 * \param avc The vcache which is being extended (locked)
3852 * \param alen The new length of the file
3855 void afs_PopulateDCache(struct vcache *avc, afs_size_t apos, struct vrequest *areq) {
3857 afs_size_t len, offset;
3858 afs_int32 start, end;
3860 /* We're doing this to deal with the situation where we extend
3861 * by writing after lseek()ing past the end of the file . If that
3862 * extension skips chunks, then those chunks won't be created, and
3863 * GetDCache will assume that they have to be fetched from the server.
3864 * So, for each chunk between the current file position, and the new
3865 * length we GetDCache for that chunk.
3868 if (AFS_CHUNK(apos) == 0 || apos <= avc->f.m.Length)
3871 if (avc->f.m.Length == 0)
3874 start = AFS_CHUNK(avc->f.m.Length)+1;
3876 end = AFS_CHUNK(apos);
3879 len = AFS_CHUNKTOSIZE(start);
3880 tdc = afs_GetDCache(avc, AFS_CHUNKTOBASE(start), areq, &offset, &len, 4);