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
10 #include <afsconfig.h>
11 #include "afs/param.h"
16 #include <sys/sleep.h>
19 #include "afs/sysincludes.h" /* Standard vendor system headers */
20 #include "afsincludes.h" /* Afs-based standard headers */
21 #include "afs/afs_stats.h" /* statistics gathering code */
22 #include "afs/afs_cbqueue.h"
24 #include <sys/adspace.h> /* for vm_att(), vm_det() */
27 #if defined(AFS_CACHE_BYPASS)
28 #include "afs/afs_bypasscache.h"
29 #endif// defined(AFS_CACHE_BYPASS)
30 /* background request queue size */
31 afs_lock_t afs_xbrs; /* lock for brs */
32 static int brsInit = 0;
33 short afs_brsWaiters = 0; /* number of users waiting for brs buffers */
34 short afs_brsDaemons = 0; /* number of daemons waiting for brs requests */
35 struct brequest afs_brs[NBRS]; /* request structures */
36 struct afs_osi_WaitHandle AFS_WaitHandler, AFS_CSWaitHandler;
37 static int afs_brs_count = 0; /* request counter, to service reqs in order */
39 static int rxepoch_checked = 0;
40 #define afs_CheckRXEpoch() {if (rxepoch_checked == 0 && rxkad_EpochWasSet) { \
41 rxepoch_checked = 1; afs_GCUserData(/* force flag */ 1); } }
43 /* PAG garbage collection */
44 /* We induce a compile error if param.h does not define AFS_GCPAGS */
45 afs_int32 afs_gcpags = AFS_GCPAGS;
46 afs_int32 afs_gcpags_procsize = 0;
48 afs_int32 afs_CheckServerDaemonStarted = 0;
49 #ifndef DEFAULT_PROBE_INTERVAL
50 #define DEFAULT_PROBE_INTERVAL 30 /* default to 3 min */
52 afs_int32 afs_probe_interval = DEFAULT_PROBE_INTERVAL;
53 afs_int32 afs_probe_all_interval = 600;
54 afs_int32 afs_nat_probe_interval = 60;
55 afs_int32 afs_preCache = 0;
57 #define PROBE_WAIT() (1000 * (afs_probe_interval - ((afs_random() & 0x7fffffff) \
58 % (afs_probe_interval/2))))
61 afs_SetCheckServerNATmode(int isnat)
63 static afs_int32 old_intvl, old_all_intvl;
66 if (isnat && !wasnat) {
67 old_intvl = afs_probe_interval;
68 old_all_intvl = afs_probe_all_interval;
69 afs_probe_interval = afs_nat_probe_interval;
70 afs_probe_all_interval = afs_nat_probe_interval;
71 afs_osi_CancelWait(&AFS_CSWaitHandler);
72 } else if (!isnat && wasnat) {
73 afs_probe_interval = old_intvl;
74 afs_probe_all_interval = old_all_intvl;
80 afs_CheckServerDaemon(void)
82 afs_int32 now, delay, lastCheck, last10MinCheck;
84 afs_CheckServerDaemonStarted = 1;
86 while (afs_initState < 101)
87 afs_osi_Sleep(&afs_initState);
88 afs_osi_Wait(PROBE_WAIT(), &AFS_CSWaitHandler, 0);
90 last10MinCheck = lastCheck = osi_Time();
92 if (afs_termState == AFSOP_STOP_CS) {
93 afs_termState = AFSOP_STOP_BKG;
94 afs_osi_Wakeup(&afs_termState);
99 if (afs_probe_interval + lastCheck <= now) {
100 afs_CheckServers(1, NULL); /* check down servers */
101 lastCheck = now = osi_Time();
104 if (afs_probe_all_interval + last10MinCheck <= now) {
105 afs_Trace1(afs_iclSetp, CM_TRACE_PROBEUP, ICL_TYPE_INT32, afs_probe_all_interval);
106 afs_CheckServers(0, NULL);
107 last10MinCheck = now = osi_Time();
109 /* shutdown check. */
110 if (afs_termState == AFSOP_STOP_CS) {
111 afs_termState = AFSOP_STOP_BKG;
112 afs_osi_Wakeup(&afs_termState);
116 /* Compute time to next probe. */
117 delay = afs_probe_interval + lastCheck;
118 if (delay > afs_probe_all_interval + last10MinCheck)
119 delay = afs_probe_all_interval + last10MinCheck;
123 afs_osi_Wait(delay * 1000, &AFS_CSWaitHandler, 0);
125 afs_CheckServerDaemonStarted = 0;
128 extern int vfs_context_ref;
130 /* This function always holds the GLOCK whilst it is running. The caller
131 * gets the GLOCK before invoking it, and afs_osi_Sleep drops the GLOCK
132 * whilst we are sleeping, and regains it when we're woken up.
138 struct afs_exporter *exporter;
140 afs_int32 last3MinCheck, last10MinCheck, last60MinCheck, lastNMinCheck;
141 afs_int32 last1MinCheck, last5MinCheck;
142 afs_uint32 lastCBSlotBump;
145 AFS_STATCNT(afs_Daemon);
146 last1MinCheck = last3MinCheck = last60MinCheck = last10MinCheck =
147 last5MinCheck = lastNMinCheck = 0;
149 afs_rootFid.Fid.Volume = 0;
150 while (afs_initState < 101)
151 afs_osi_Sleep(&afs_initState);
153 #ifdef AFS_DARWIN80_ENV
154 if (afs_osi_ctxtp_initialized)
155 osi_Panic("vfs context already initialized");
156 while (afs_osi_ctxtp && vfs_context_ref)
157 afs_osi_Sleep(&afs_osi_ctxtp);
158 if (afs_osi_ctxtp && !vfs_context_ref)
159 vfs_context_rele(afs_osi_ctxtp);
160 afs_osi_ctxtp = vfs_context_create(NULL);
161 afs_osi_ctxtp_initialized = 1;
164 lastCBSlotBump = now;
166 /* when a lot of clients are booted simultaneously, they develop
167 * annoying synchronous VL server bashing behaviors. So we stagger them.
169 last1MinCheck = now + ((afs_random() & 0x7fffffff) % 60); /* an extra 30 */
170 last3MinCheck = now - 90 + ((afs_random() & 0x7fffffff) % 180);
171 last60MinCheck = now - 1800 + ((afs_random() & 0x7fffffff) % 3600);
172 last10MinCheck = now - 300 + ((afs_random() & 0x7fffffff) % 600);
173 last5MinCheck = now - 150 + ((afs_random() & 0x7fffffff) % 300);
174 lastNMinCheck = now - 90 + ((afs_random() & 0x7fffffff) % 180);
176 /* start off with afs_initState >= 101 (basic init done) */
178 afs_CheckCallbacks(20); /* unstat anything which will expire soon */
180 /* things to do every 20 seconds or less - required by protocol spec */
182 afs_FlushActiveVcaches(0); /* flush NFS writes */
183 afs_FlushVCBs(1); /* flush queued callbacks */
185 #if defined(AFS_NBSD50_ENV)
189 c1 = ISAFS_GLOCK(); /* this thread owns the GLOCK */
191 c2 = mutex_tryenter(&afs_global_mtx); /* not held either */
197 printf("afs_daemons periodic glock check: curthread owns glock %s; "
198 "glock held somewhere %s\n",
199 c1 ? "true" : "false",
200 c2 ? "true" : "false");
204 afs_MaybeWakeupTruncateDaemon(); /* free cache space if have too */
205 rx_CheckPackets(); /* Does RX need more packets? */
208 if (lastCBSlotBump + CBHTSLOTLEN < now) { /* pretty time-dependant */
209 lastCBSlotBump = now;
210 if (afs_BumpBase()) {
211 afs_CheckCallbacks(20); /* unstat anything which will expire soon */
215 if (last1MinCheck + 60 < now) {
216 /* things to do every minute */
217 DFlush(); /* write out dir buffers */
218 afs_WriteThroughDSlots(); /* write through cacheinfo entries */
219 ObtainWriteLock(&afs_xvcache, 736);
220 afs_FlushReclaimedVcaches();
221 ReleaseWriteLock(&afs_xvcache);
222 afs_FlushActiveVcaches(1); /* keep flocks held & flush nfs writes */
224 afs_StoreDirtyVcaches();
230 if (last3MinCheck + 180 < now) {
231 afs_CheckTokenCache(); /* check for access cache resets due to expired
236 if (afsd_dynamic_vcaches && (last5MinCheck + 300 < now)) {
237 /* start with trying to drop us back to our base usage */
239 if (afs_maxvcount <= afs_cacheStats)
240 anumber = VCACHE_FREE;
242 anumber = VCACHE_FREE + (afs_maxvcount - afs_cacheStats);
244 ObtainWriteLock(&afs_xvcache, 734);
245 afs_ShakeLooseVCaches(anumber);
246 ReleaseWriteLock(&afs_xvcache);
250 if (!afs_CheckServerDaemonStarted) {
251 /* Do the check here if the correct afsd is not installed. */
254 afs_warn("Please install afsd with check server daemon.\n");
256 if (lastNMinCheck + afs_probe_interval < now) {
257 /* only check down servers */
258 afs_CheckServers(1, NULL);
262 if (last10MinCheck + 600 < now) {
263 #ifdef AFS_USERSPACE_IP_ADDR
264 extern int rxi_GetcbiInfo(void);
266 afs_Trace1(afs_iclSetp, CM_TRACE_PROBEUP, ICL_TYPE_INT32, 600);
267 #ifdef AFS_USERSPACE_IP_ADDR
268 if (rxi_GetcbiInfo()) { /* addresses changed from last time */
271 #else /* AFS_USERSPACE_IP_ADDR */
272 if (rxi_GetIFInfo()) { /* addresses changed from last time */
275 #endif /* else AFS_USERSPACE_IP_ADDR */
276 if (!afs_CheckServerDaemonStarted)
277 afs_CheckServers(0, NULL);
278 afs_GCUserData(0); /* gc old conns */
279 /* This is probably the wrong way of doing GC for the various exporters but it will suffice for a while */
280 for (exporter = root_exported; exporter;
281 exporter = exporter->exp_next) {
282 (void)EXP_GC(exporter, 0); /* Generalize params */
287 afs_CheckVolumeNames(AFS_VOLCHECK_EXPIRED |
291 afs_CheckVolumeNames(AFS_VOLCHECK_EXPIRED |
296 last10MinCheck = now;
298 if (last60MinCheck + 3600 < now) {
299 afs_Trace1(afs_iclSetp, CM_TRACE_PROBEVOLUME, ICL_TYPE_INT32,
301 afs_CheckRootVolume();
303 if (afs_gcpags == AFS_GCPAGS_OK) {
308 last60MinCheck = now;
310 if (afs_initState < 300) { /* while things ain't rosy */
311 code = afs_CheckRootVolume();
313 afs_initState = 300; /* succeeded */
314 if (afs_initState < 200)
315 afs_initState = 200; /* tried once */
316 afs_osi_Wakeup(&afs_initState);
319 /* 18285 is because we're trying to divide evenly into 128, that is,
320 * CBSlotLen, while staying just under 20 seconds. If CBSlotLen
321 * changes, should probably change this interval, too.
322 * Some of the preceding actions may take quite some time, so we
323 * might not want to wait the entire interval */
324 now = 18285 - (osi_Time() - now);
326 afs_osi_Wait(now, &AFS_WaitHandler, 0);
329 if (afs_termState == AFSOP_STOP_AFS) {
330 if (afs_CheckServerDaemonStarted)
331 afs_termState = AFSOP_STOP_CS;
333 afs_termState = AFSOP_STOP_BKG;
334 afs_osi_Wakeup(&afs_termState);
341 afs_CheckRootVolume(void)
343 char rootVolName[32];
344 struct volume *tvp = NULL;
345 int usingDynroot = afs_GetDynrootEnable();
348 AFS_STATCNT(afs_CheckRootVolume);
349 if (*afs_rootVolumeName == 0) {
350 strcpy(rootVolName, "root.afs");
352 strcpy(rootVolName, afs_rootVolumeName);
356 afs_GetDynrootFid(&afs_rootFid);
357 tvp = afs_GetVolume(&afs_rootFid, NULL, READ_LOCK);
359 struct cell *lc = afs_GetPrimaryCell(READ_LOCK);
363 localcell = lc->cellNum;
364 afs_PutCell(lc, READ_LOCK);
365 tvp = afs_GetVolumeByName(rootVolName, localcell, 1, NULL, READ_LOCK);
368 int len = strlen(rootVolName);
370 if ((len < 9) || strcmp(&rootVolName[len - 9], ".readonly")) {
371 strcpy(buf, rootVolName);
372 afs_strcat(buf, ".readonly");
373 tvp = afs_GetVolumeByName(buf, localcell, 1, NULL, READ_LOCK);
377 int volid = (tvp->roVol ? tvp->roVol : tvp->volume);
378 afs_rootFid.Cell = localcell;
379 if (afs_rootFid.Fid.Volume && afs_rootFid.Fid.Volume != volid
381 /* If we had a root fid before and it changed location we reset
382 * the afs_globalVp so that it will be reevaluated.
383 * Just decrement the reference count. This only occurs during
384 * initial cell setup and can panic the machine if we set the
385 * count to zero and fs checkv is executed when the current
388 #ifdef AFS_LINUX20_ENV
390 struct vrequest treq;
396 afs_rootFid.Fid.Volume = volid;
397 afs_rootFid.Fid.Vnode = 1;
398 afs_rootFid.Fid.Unique = 1;
401 if (afs_InitReq(&treq, credp))
403 vcp = afs_GetVCache(&afs_rootFid, &treq, NULL, NULL);
406 afs_getattr(vcp, &vattr, credp);
407 afs_fill_inode(AFSTOV(vcp), &vattr);
409 dp = d_find_alias(AFSTOV(afs_globalVp));
411 #if defined(AFS_LINUX24_ENV)
412 spin_lock(&dcache_lock);
413 #if defined(AFS_LINUX26_ENV)
414 spin_lock(&dp->d_lock);
417 list_del_init(&dp->d_alias);
418 list_add(&dp->d_alias, &(AFSTOV(vcp)->i_dentry));
419 dp->d_inode = AFSTOV(vcp);
420 #if defined(AFS_LINUX24_ENV)
421 #if defined(AFS_LINUX26_ENV)
422 spin_unlock(&dp->d_lock);
424 spin_unlock(&dcache_lock);
428 AFS_FAST_RELE(afs_globalVp);
434 #ifdef AFS_DARWIN80_ENV
435 afs_PutVCache(afs_globalVp);
437 AFS_FAST_RELE(afs_globalVp);
442 afs_rootFid.Fid.Volume = volid;
443 afs_rootFid.Fid.Vnode = 1;
444 afs_rootFid.Fid.Unique = 1;
448 afs_initState = 300; /* won */
449 afs_osi_Wakeup(&afs_initState);
450 afs_PutVolume(tvp, READ_LOCK);
452 if (afs_rootFid.Fid.Volume)
458 /* ptr_parm 0 is the pathname, size_parm 0 to the fetch is the chunk number */
460 BPath(struct brequest *ab)
462 struct dcache *tdc = NULL;
463 struct vcache *tvc = NULL;
464 struct vnode *tvn = NULL;
465 #ifdef AFS_LINUX22_ENV
466 struct dentry *dp = NULL;
468 afs_size_t offset, len;
469 struct vrequest treq;
473 if ((code = afs_InitReq(&treq, ab->cred)))
476 #ifdef AFS_LINUX22_ENV
477 code = gop_lookupname((char *)ab->ptr_parm[0], AFS_UIOSYS, 1, &dp);
479 tvn = (struct vnode *)dp->d_inode;
481 code = gop_lookupname((char *)ab->ptr_parm[0], AFS_UIOSYS, 1, &tvn);
484 osi_FreeLargeSpace((char *)ab->ptr_parm[0]); /* free path name buffer here */
487 /* now path may not have been in afs, so check that before calling our cache manager */
488 if (!tvn || !IsAfsVnode(tvn)) {
489 /* release it and give up */
491 #ifdef AFS_LINUX22_ENV
500 /* here we know its an afs vnode, so we can get the data for the chunk */
501 tdc = afs_GetDCache(tvc, ab->size_parm[0], &treq, &offset, &len, 1);
505 #ifdef AFS_LINUX22_ENV
512 /* size_parm 0 to the fetch is the chunk number,
513 * ptr_parm 0 is the dcache entry to wakeup,
514 * size_parm 1 is true iff we should release the dcache entry here.
517 BPrefetch(struct brequest *ab)
521 afs_size_t offset, len, abyte, totallen = 0;
522 struct vrequest treq;
524 AFS_STATCNT(BPrefetch);
525 if ((len = afs_InitReq(&treq, ab->cred)))
527 abyte = ab->size_parm[0];
530 tdc = afs_GetDCache(tvc, abyte, &treq, &offset, &len, 1);
536 } while ((totallen < afs_preCache) && tdc && (len > 0));
537 /* now, dude may be waiting for us to clear DFFetchReq bit; do so. Can't
538 * use tdc from GetDCache since afs_GetDCache may fail, but someone may
539 * be waiting for our wakeup anyway.
541 tdc = (struct dcache *)(ab->ptr_parm[0]);
542 ObtainSharedLock(&tdc->lock, 640);
543 if (tdc->mflags & DFFetchReq) {
544 UpgradeSToWLock(&tdc->lock, 641);
545 tdc->mflags &= ~DFFetchReq;
546 ReleaseWriteLock(&tdc->lock);
548 ReleaseSharedLock(&tdc->lock);
550 afs_osi_Wakeup(&tdc->validPos);
551 if (ab->size_parm[1]) {
552 afs_PutDCache(tdc); /* put this one back, too */
556 #if defined(AFS_CACHE_BYPASS)
558 BPrefetchNoCache(struct brequest *ab)
560 struct vrequest treq;
563 if ((len = afs_InitReq(&treq, ab->cred)))
567 /* OS-specific prefetch routine */
568 afs_PrefetchNoCache(ab->vc, ab->cred, (struct nocache_read_request *) ab->ptr_parm[0]);
574 BStore(struct brequest *ab)
578 struct vrequest treq;
579 #if defined(AFS_SGI_ENV)
580 struct cred *tmpcred;
584 if ((code = afs_InitReq(&treq, ab->cred)))
588 #if defined(AFS_SGI_ENV)
590 * Since StoreOnLastReference can end up calling osi_SyncVM which
591 * calls into VM code that assumes that u.u_cred has the
592 * correct credentials, we set our to theirs for this xaction
594 tmpcred = OSI_GET_CURRENT_CRED();
595 OSI_SET_CURRENT_CRED(ab->cred);
598 * To avoid recursion since the WriteLock may be released during VM
599 * operations, we hold the VOP_RWLOCK across this transaction as
600 * do the other callers of StoreOnLastReference
602 AFS_RWLOCK((vnode_t *) tvc, 1);
604 ObtainWriteLock(&tvc->lock, 209);
605 code = afs_StoreOnLastReference(tvc, &treq);
606 ReleaseWriteLock(&tvc->lock);
607 #if defined(AFS_SGI_ENV)
608 OSI_SET_CURRENT_CRED(tmpcred);
609 AFS_RWUNLOCK((vnode_t *) tvc, 1);
611 /* now set final return code, and wakeup anyone waiting */
612 if ((ab->flags & BUVALID) == 0) {
613 ab->code = afs_CheckCode(code, &treq, 43); /* set final code, since treq doesn't go across processes */
614 ab->flags |= BUVALID;
615 if (ab->flags & BUWAIT) {
616 ab->flags &= ~BUWAIT;
622 /* release a held request buffer */
624 afs_BRelease(struct brequest *ab)
627 AFS_STATCNT(afs_BRelease);
628 ObtainWriteLock(&afs_xbrs, 294);
629 if (--ab->refCount <= 0) {
633 afs_osi_Wakeup(&afs_brsWaiters);
634 ReleaseWriteLock(&afs_xbrs);
637 /* return true if bkg fetch daemons are all busy */
641 AFS_STATCNT(afs_BBusy);
642 if (afs_brsDaemons > 0)
648 afs_BQueue(short aopcode, struct vcache *avc,
649 afs_int32 dontwait, afs_int32 ause, afs_ucred_t *acred,
650 afs_size_t asparm0, afs_size_t asparm1, void *apparm0,
651 void *apparm1, void *apparm2)
656 AFS_STATCNT(afs_BQueue);
657 ObtainWriteLock(&afs_xbrs, 296);
660 for (i = 0; i < NBRS; i++, tb++) {
661 if (tb->refCount == 0)
666 tb->opcode = aopcode;
673 tb->refCount = ause + 1;
674 tb->size_parm[0] = asparm0;
675 tb->size_parm[1] = asparm1;
676 tb->ptr_parm[0] = apparm0;
677 tb->ptr_parm[1] = apparm1;
678 tb->ptr_parm[2] = apparm2;
681 tb->ts = afs_brs_count++;
682 /* if daemons are waiting for work, wake them up */
683 if (afs_brsDaemons > 0) {
684 afs_osi_Wakeup(&afs_brsDaemons);
686 ReleaseWriteLock(&afs_xbrs);
690 ReleaseWriteLock(&afs_xbrs);
693 /* no free buffers, sleep a while */
695 ReleaseWriteLock(&afs_xbrs);
696 afs_osi_Sleep(&afs_brsWaiters);
697 ObtainWriteLock(&afs_xbrs, 301);
703 /* AIX 4.1 has a much different sleep/wakeup mechanism available for use.
704 * The modifications here will work for either a UP or MP machine.
706 struct buf *afs_asyncbuf = (struct buf *)0;
707 tid_t afs_asyncbuf_cv = EVENT_NULL;
708 afs_int32 afs_biodcnt = 0;
710 /* in implementing this, I assumed that all external linked lists were
713 * Several places in this code traverse a linked list. The algorithm
714 * used here is probably unfamiliar to most people. Careful examination
715 * will show that it eliminates an assignment inside the loop, as compared
716 * to the standard algorithm, at the cost of occasionally using an extra
722 * This function obtains, and returns, a pointer to a buffer for
723 * processing by a daemon. It sleeps until such a buffer is available.
724 * The source of buffers for it is the list afs_asyncbuf (see also
725 * afs_gn_strategy). This function may be invoked concurrently by
726 * several processes, that is, several instances of the same daemon.
727 * afs_gn_strategy, which adds buffers to the list, runs at interrupt
728 * level, while get_bioreq runs at process level.
730 * Since AIX 4.1 can wake just one process at a time, the separate sleep
731 * addresses have been removed.
732 * Note that the kernel_lock is held until the e_sleep_thread() occurs.
733 * The afs_asyncbuf_lock is primarily used to serialize access between
734 * process and interrupts.
736 Simple_lock afs_asyncbuf_lock;
740 struct buf *bp = NULL;
742 struct buf **bestlbpP, **lbpP;
744 struct buf *t1P, *t2P; /* temp pointers for list manipulation */
747 struct afs_bioqueue *s;
749 /* ??? Does the forward pointer of the returned buffer need to be NULL?
752 /* Disable interrupts from the strategy function, and save the
753 * prior priority level and lock access to the afs_asyncbuf.
756 oldPriority = disable_lock(INTMAX, &afs_asyncbuf_lock);
760 /* look for oldest buffer */
761 bp = bestbp = afs_asyncbuf;
762 bestage = (long)bestbp->av_back;
763 bestlbpP = &afs_asyncbuf;
769 if ((long)bp->av_back - bestage < 0) {
772 bestage = (long)bp->av_back;
776 *bestlbpP = bp->av_forw;
779 /* If afs_asyncbuf is null, it is necessary to go to sleep.
780 * e_wakeup_one() ensures that only one thread wakes.
783 /* The LOCK_HANDLER indicates to e_sleep_thread to only drop the
784 * lock on an MP machine.
787 e_sleep_thread(&afs_asyncbuf_cv, &afs_asyncbuf_lock,
788 LOCK_HANDLER | INTERRUPTIBLE);
789 if (interrupted == THREAD_INTERRUPTED) {
790 /* re-enable interrupts from strategy */
791 unlock_enable(oldPriority, &afs_asyncbuf_lock);
795 } /* end of "else asyncbuf is empty" */
796 } /* end of "inner loop" */
800 unlock_enable(oldPriority, &afs_asyncbuf_lock);
803 /* For the convenience of other code, replace the gnodes in
804 * the b_vp field of bp and the other buffers on the b_work
805 * chain with the corresponding vnodes.
807 * ??? what happens to the gnodes? They're not just cut loose,
811 t2P = (struct buf *)t1P->b_work;
812 t1P->b_vp = ((struct gnode *)t1P->b_vp)->gn_vnode;
816 t1P = (struct buf *)t2P->b_work;
817 t2P->b_vp = ((struct gnode *)t2P->b_vp)->gn_vnode;
822 /* If the buffer does not specify I/O, it may immediately
823 * be returned to the caller. This condition is detected
824 * by examining the buffer's flags (the b_flags field). If
825 * the B_PFPROT bit is set, the buffer represents a protection
826 * violation, rather than a request for I/O. The remainder
827 * of the outer loop handles the case where the B_PFPROT bit is clear.
829 if (bp->b_flags & B_PFPROT) {
834 } /* end of function get_bioreq() */
839 * This function is the daemon. It is called from the syscall
840 * interface. Ordinarily, a script or an administrator will run a
841 * daemon startup utility, specifying the number of I/O daemons to
842 * run. The utility will fork off that number of processes,
843 * each making the appropriate syscall, which will cause this
844 * function to be invoked.
846 static int afs_initbiod = 0; /* this is self-initializing code */
849 afs_BioDaemon(afs_int32 nbiods)
851 afs_int32 code, s, pflg = 0;
853 struct buf *bp, *bp1, *tbp1, *tbp2; /* temp pointers only */
861 /* pin lock, since we'll be using it in an interrupt. */
862 lock_alloc(&afs_asyncbuf_lock, LOCK_ALLOC_PIN, 2, 1);
863 simple_lock_init(&afs_asyncbuf_lock);
864 pin(&afs_asyncbuf, sizeof(struct buf *));
865 pin(&afs_asyncbuf_cv, sizeof(afs_int32));
868 /* Ignore HUP signals... */
870 sigset_t sigbits, osigbits;
872 * add SIGHUP to the set of already masked signals
874 SIGFILLSET(sigbits); /* allow all signals */
875 SIGDELSET(sigbits, SIGHUP); /* except SIGHUP */
876 limit_sigs(&sigbits, &osigbits); /* and already masked */
878 /* Main body starts here -- this is an intentional infinite loop, and
881 * Now, the loop will exit if get_bioreq() returns NULL, indicating
882 * that we've been interrupted.
885 bp = afs_get_bioreq();
887 break; /* we were interrupted */
888 if (code = setjmpx(&jmpbuf)) {
889 /* This should not have happend, maybe a lack of resources */
891 s = disable_lock(INTMAX, &afs_asyncbuf_lock);
892 for (bp1 = bp; bp; bp = bp1) {
894 bp1 = (struct buf *)bp1->b_work;
897 bp->b_flags |= B_ERROR;
900 unlock_enable(s, &afs_asyncbuf_lock);
904 vcp = VTOAFS(bp->b_vp);
905 if (bp->b_flags & B_PFSTORE) { /* XXXX */
906 ObtainWriteLock(&vcp->lock, 404);
907 if (vcp->v.v_gnode->gn_mwrcnt) {
908 afs_offs_t newlength =
909 (afs_offs_t) dbtob(bp->b_blkno) + bp->b_bcount;
910 if (vcp->f.m.Length < newlength) {
911 afs_Trace4(afs_iclSetp, CM_TRACE_SETLENGTH,
912 ICL_TYPE_STRING, __FILE__, ICL_TYPE_LONG,
913 __LINE__, ICL_TYPE_OFFSET,
914 ICL_HANDLE_OFFSET(vcp->f.m.Length),
915 ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(newlength));
916 vcp->f.m.Length = newlength;
919 ReleaseWriteLock(&vcp->lock);
921 /* If the buffer represents a protection violation, rather than
922 * an actual request for I/O, no special action need be taken.
924 if (bp->b_flags & B_PFPROT) {
925 iodone(bp); /* Notify all users of the buffer that we're done */
930 ObtainWriteLock(&vcp->pvmlock, 211);
932 * First map its data area to a region in the current address space
933 * by calling vm_att with the subspace identifier, and a pointer to
934 * the data area. vm_att returns a new data area pointer, but we
935 * also want to hang onto the old one.
937 tmpaddr = bp->b_baddr;
938 bp->b_baddr = (caddr_t) vm_att(bp->b_xmemd.subspace_id, tmpaddr);
939 tmperr = afs_ustrategy(bp); /* temp variable saves offset calculation */
940 if (tmperr) { /* in non-error case */
941 bp->b_flags |= B_ERROR; /* should other flags remain set ??? */
942 bp->b_error = tmperr;
945 /* Unmap the buffer's data area by calling vm_det. Reset data area
946 * to the value that we saved above.
949 bp->b_baddr = tmpaddr;
952 * buffer may be linked with other buffers via the b_work field.
953 * See also afs_gn_strategy. For each buffer in the chain (including
954 * bp) notify all users of the buffer that the daemon is finished
955 * using it by calling iodone.
956 * assumes iodone can modify the b_work field.
959 tbp2 = (struct buf *)tbp1->b_work;
964 tbp1 = (struct buf *)tbp2->b_work;
970 ReleaseWriteLock(&vcp->pvmlock); /* Unlock the vnode. */
972 } /* infinite loop (unless we're interrupted) */
973 } /* end of afs_BioDaemon() */
975 #endif /* AFS_AIX41_ENV */
980 afs_BackgroundDaemon_once(void)
982 LOCK_INIT(&afs_xbrs, "afs_xbrs");
983 memset(afs_brs, 0, sizeof(afs_brs));
985 #if defined (AFS_SGI_ENV) && defined(AFS_SGI_SHORTSTACK)
987 * steal the first daemon for doing delayed DSlot flushing
988 * (see afs_GetDownDSlot)
997 brequest_release(struct brequest *tb)
1000 AFS_RELE(AFSTOV(tb->vc)); /* MUST call vnode layer or could lose vnodes */
1005 tb->cred = (afs_ucred_t *)0;
1007 afs_BRelease(tb); /* this grabs and releases afs_xbrs lock */
1010 #ifdef AFS_DARWIN80_ENV
1012 afs_BackgroundDaemon(struct afs_uspc_param *uspc, void *param1, void *param2)
1015 afs_BackgroundDaemon(void)
1018 struct brequest *tb;
1021 AFS_STATCNT(afs_BackgroundDaemon);
1022 /* initialize subsystem */
1024 /* Irix with "short stack" exits */
1025 afs_BackgroundDaemon_once();
1027 #ifdef AFS_DARWIN80_ENV
1028 /* If it's a re-entering syscall, complete the request and release */
1029 if (uspc->ts > -1) {
1031 for (i = 0; i < NBRS; i++, tb++) {
1032 if (tb->ts == uspc->ts) {
1033 /* copy the userspace status back in */
1034 ((struct afs_uspc_param *) tb->ptr_parm[0])->retval =
1036 /* mark it valid and notify our caller */
1037 tb->flags |= BUVALID;
1038 if (tb->flags & BUWAIT) {
1039 tb->flags &= ~BUWAIT;
1042 brequest_release(tb);
1047 afs_osi_MaskUserLoop();
1049 /* Otherwise it's a new one */
1051 #ifdef AFS_DARWIN80_ENV
1055 ObtainWriteLock(&afs_xbrs, 302);
1058 struct brequest *min_tb = NULL;
1060 if (afs_termState == AFSOP_STOP_BKG) {
1061 if (--afs_nbrs <= 0)
1062 afs_termState = AFSOP_STOP_TRUNCDAEMON;
1063 ReleaseWriteLock(&afs_xbrs);
1064 afs_osi_Wakeup(&afs_termState);
1065 #ifdef AFS_DARWIN80_ENV
1072 /* find a request */
1075 for (i = 0; i < NBRS; i++, tb++) {
1076 /* look for request with smallest ts */
1077 if ((tb->refCount > 0) && !(tb->flags & BSTARTED)) {
1078 /* new request, not yet picked up */
1079 if ((min_tb && (min_ts - tb->ts > 0)) || !min_tb) {
1085 if ((tb = min_tb)) {
1086 /* claim and process this request */
1087 tb->flags |= BSTARTED;
1088 ReleaseWriteLock(&afs_xbrs);
1090 afs_Trace1(afs_iclSetp, CM_TRACE_BKG1, ICL_TYPE_INT32,
1092 if (tb->opcode == BOP_FETCH)
1094 #if defined(AFS_CACHE_BYPASS)
1095 else if (tb->opcode == BOP_FETCH_NOCACHE)
1096 BPrefetchNoCache(tb);
1098 else if (tb->opcode == BOP_STORE)
1100 else if (tb->opcode == BOP_PATH)
1102 #ifdef AFS_DARWIN80_ENV
1103 else if (tb->opcode == BOP_MOVE) {
1104 memcpy(uspc, (struct afs_uspc_param *) tb->ptr_parm[0],
1105 sizeof(struct afs_uspc_param));
1107 /* string lengths capped in move vop; copy NUL tho */
1108 memcpy(param1, (char *)tb->ptr_parm[1],
1109 strlen(tb->ptr_parm[1])+1);
1110 memcpy(param2, (char *)tb->ptr_parm[2],
1111 strlen(tb->ptr_parm[2])+1);
1116 panic("background bop");
1117 brequest_release(tb);
1118 ObtainWriteLock(&afs_xbrs, 305);
1121 /* wait for new request */
1123 ReleaseWriteLock(&afs_xbrs);
1124 afs_osi_Sleep(&afs_brsDaemons);
1125 ObtainWriteLock(&afs_xbrs, 307);
1129 #ifdef AFS_DARWIN80_ENV
1136 shutdown_daemons(void)
1138 AFS_STATCNT(shutdown_daemons);
1139 if (afs_cold_shutdown) {
1140 afs_brsDaemons = brsInit = 0;
1141 rxepoch_checked = afs_nbrs = 0;
1142 memset(afs_brs, 0, sizeof(afs_brs));
1143 memset(&afs_xbrs, 0, sizeof(afs_lock_t));
1145 #ifdef AFS_AIX41_ENV
1146 lock_free(&afs_asyncbuf_lock);
1147 unpin(&afs_asyncbuf, sizeof(struct buf *));
1148 unpin(&afs_asyncbuf_cv, sizeof(afs_int32));
1154 #if defined(AFS_SGI_ENV) && defined(AFS_SGI_SHORTSTACK)
1156 * sgi - daemon - handles certain operations that otherwise
1157 * would use up too much kernel stack space
1159 * This all assumes that since the caller must have the xdcache lock
1160 * exclusively that the list will never be more than one long
1161 * and noone else can attempt to add anything until we're done.
1163 SV_TYPE afs_sgibksync;
1164 SV_TYPE afs_sgibkwait;
1165 lock_t afs_sgibklock;
1166 struct dcache *afs_sgibklist;
1174 if (afs_sgibklock == NULL) {
1175 SV_INIT(&afs_sgibksync, "bksync", 0, 0);
1176 SV_INIT(&afs_sgibkwait, "bkwait", 0, 0);
1177 SPINLOCK_INIT(&afs_sgibklock, "bklock");
1179 s = SPLOCK(afs_sgibklock);
1181 /* wait for something to do */
1182 SP_WAIT(afs_sgibklock, s, &afs_sgibksync, PINOD);
1183 osi_Assert(afs_sgibklist);
1185 /* XX will probably need to generalize to real list someday */
1186 s = SPLOCK(afs_sgibklock);
1187 while (afs_sgibklist) {
1188 tdc = afs_sgibklist;
1189 afs_sgibklist = NULL;
1190 SPUNLOCK(afs_sgibklock, s);
1192 tdc->dflags &= ~DFEntryMod;
1193 afs_WriteDCache(tdc, 1);
1195 s = SPLOCK(afs_sgibklock);
1198 /* done all the work - wake everyone up */
1199 while (SV_SIGNAL(&afs_sgibkwait));