/* * Copyright (C) 1998, 1989 Transarc Corporation - All rights reserved * * (C) COPYRIGHT IBM CORPORATION 1987, 1988 * LICENSED MATERIALS - PROPERTY OF IBM * * */ #include #include #include #include #include #include #include #include #include #include "afsd.h" extern osi_hyper_t hzero; /* hash table stuff */ cm_scache_t **cm_hashTablep; long cm_hashTableSize; long cm_maxSCaches; long cm_currentSCaches; /* LRU stuff */ cm_scache_t *cm_scacheLRUFirstp; cm_scache_t *cm_scacheLRULastp; /* File locks */ osi_queue_t *cm_allFileLocks; /* lock for globals */ osi_rwlock_t cm_scacheLock; /* Dummy scache entry for use with pioctl fids */ cm_scache_t cm_fakeSCache; /* must be called with cm_scacheLock write-locked! */ void cm_AdjustLRU(cm_scache_t *scp) { if (scp == cm_scacheLRULastp) cm_scacheLRULastp = (cm_scache_t *) osi_QPrev(&scp->q); osi_QRemove((osi_queue_t **) &cm_scacheLRUFirstp, &scp->q); osi_QAdd((osi_queue_t **) &cm_scacheLRUFirstp, &scp->q); if (!cm_scacheLRULastp) cm_scacheLRULastp = scp; } /* called with cm_scacheLock write-locked; find a vnode to recycle. * Can allocate a new one if desperate, or if below quota (cm_maxSCaches). */ cm_scache_t *cm_GetNewSCache(void) { cm_scache_t *scp; int i; cm_scache_t **lscpp; cm_scache_t *tscp; if (cm_currentSCaches >= cm_maxSCaches) { for (scp = cm_scacheLRULastp; scp; scp = (cm_scache_t *) osi_QPrev(&scp->q)) { if (scp->refCount == 0) break; } if (scp) { /* we found an entry, so return it */ if (scp->flags & CM_SCACHEFLAG_INHASH) { /* hash it out first */ i = CM_SCACHE_HASH(&scp->fid); lscpp = &cm_hashTablep[i]; for (tscp = *lscpp; tscp; lscpp = &tscp->nextp, tscp = *lscpp) { if (tscp == scp) break; } osi_assertx(tscp, "afsd: scache hash screwup"); *lscpp = scp->nextp; scp->flags &= ~CM_SCACHEFLAG_INHASH; } /* look for things that shouldn't still be set */ osi_assert(scp->bufWritesp == NULL); osi_assert(scp->bufReadsp == NULL); /* invalidate so next merge works fine; * also initialize some flags */ scp->flags &= ~(CM_SCACHEFLAG_STATD | CM_SCACHEFLAG_RO | CM_SCACHEFLAG_PURERO | CM_SCACHEFLAG_OVERQUOTA | CM_SCACHEFLAG_OUTOFSPACE); scp->serverModTime = 0; scp->dataVersion = 0; scp->bulkStatProgress = hzero; /* discard callback */ scp->cbServerp = NULL; scp->cbExpires = 0; /* remove from dnlc */ cm_dnlcPurgedp(scp); cm_dnlcPurgevp(scp); /* discard cached status; if non-zero, Close * tried to store this to server but failed */ scp->mask = 0; /* drop held volume ref */ if (scp->volp) { cm_PutVolume(scp->volp); scp->volp = NULL; } /* discard symlink info */ if (scp->mountPointStringp) { free(scp->mountPointStringp); scp->mountPointStringp = NULL; } if (scp->mountRootFidp) { free(scp->mountRootFidp); scp->mountRootFidp = NULL; } if (scp->dotdotFidp) { free(scp->dotdotFidp); scp->dotdotFidp = NULL; } /* not locked, but there can be no references to this guy * while we hold the global refcount lock. */ cm_FreeAllACLEnts(scp); /* now remove from the LRU queue and put it back at the * head of the LRU queue. */ cm_AdjustLRU(scp); /* and we're done */ return scp; } } /* if we get here, we should allocate a new scache entry. We either are below * quota or we have a leak and need to allocate a new one to avoid panicing. */ scp = malloc(sizeof(*scp)); memset(scp, 0, sizeof(*scp)); lock_InitializeMutex(&scp->mx, "cm_scache_t mutex"); lock_InitializeRWLock(&scp->bufCreateLock, "cm_scache_t bufCreateLock"); /* and put it in the LRU queue */ osi_QAdd((osi_queue_t **) &cm_scacheLRUFirstp, &scp->q); if (!cm_scacheLRULastp) cm_scacheLRULastp = scp; cm_currentSCaches++; cm_dnlcPurgedp(scp); /* make doubly sure that this is not in dnlc */ cm_dnlcPurgevp(scp); return scp; } /* like strcmp, only for fids */ int cm_FidCmp(cm_fid_t *ap, cm_fid_t *bp) { if (ap->vnode != bp->vnode) return 1; if (ap->volume != bp->volume) return 1; if (ap->unique != bp->unique) return 1; if (ap->cell != bp->cell) return 1; return 0; } void cm_fakeSCacheInit() { memset(&cm_fakeSCache, 0, sizeof(cm_fakeSCache)); lock_InitializeMutex(&cm_fakeSCache.mx, "cm_scache_t mutex"); cm_fakeSCache.cbServerp = (struct cm_server *)(-1); /* can leave clientModTime at 0 */ cm_fakeSCache.fileType = CM_SCACHETYPE_FILE; cm_fakeSCache.unixModeBits = 0777; cm_fakeSCache.length.LowPart = 1000; cm_fakeSCache.linkCount = 1; } void cm_InitSCache(long maxSCaches) { static osi_once_t once; if (osi_Once(&once)) { lock_InitializeRWLock(&cm_scacheLock, "cm_scacheLock"); cm_hashTableSize = maxSCaches / 2; cm_hashTablep = malloc(sizeof(cm_scache_t *) * cm_hashTableSize); memset(cm_hashTablep, 0, sizeof(cm_scache_t *) * cm_hashTableSize); cm_allFileLocks = NULL; cm_currentSCaches = 0; cm_maxSCaches = maxSCaches; cm_fakeSCacheInit(); cm_dnlcInit(); osi_EndOnce(&once); } } /* version that doesn't bother creating the entry if we don't find it */ cm_scache_t *cm_FindSCache(cm_fid_t *fidp) { long hash; cm_scache_t *scp; hash = CM_SCACHE_HASH(fidp); osi_assert(fidp->cell != 0); lock_ObtainWrite(&cm_scacheLock); for(scp=cm_hashTablep[hash]; scp; scp=scp->nextp) { if (cm_FidCmp(fidp, &scp->fid) == 0) { scp->refCount++; cm_AdjustLRU(scp); lock_ReleaseWrite(&cm_scacheLock); return scp; } } lock_ReleaseWrite(&cm_scacheLock); return NULL; } long cm_GetSCache(cm_fid_t *fidp, cm_scache_t **outScpp, cm_user_t *userp, cm_req_t *reqp) { long hash; cm_scache_t *scp; long code; cm_volume_t *volp; cm_cell_t *cellp; hash = CM_SCACHE_HASH(fidp); osi_assert(fidp->cell != 0); lock_ObtainWrite(&cm_scacheLock); for(scp=cm_hashTablep[hash]; scp; scp=scp->nextp) { if (cm_FidCmp(fidp, &scp->fid) == 0) { scp->refCount++; *outScpp = scp; cm_AdjustLRU(scp); lock_ReleaseWrite(&cm_scacheLock); return 0; } } /* otherwise, we need to find the volume */ lock_ReleaseWrite(&cm_scacheLock); /* for perf. reasons */ cellp = cm_FindCellByID(fidp->cell); if (!cellp) return CM_ERROR_NOSUCHCELL; code = cm_GetVolumeByID(cellp, fidp->volume, userp, reqp, &volp); if (code) return code; /* otherwise, we have the volume, now reverify that the scp doesn't * exist, and proceed. */ lock_ObtainWrite(&cm_scacheLock); for(scp=cm_hashTablep[hash]; scp; scp=scp->nextp) { if (cm_FidCmp(fidp, &scp->fid) == 0) { scp->refCount++; cm_AdjustLRU(scp); lock_ReleaseWrite(&cm_scacheLock); cm_PutVolume(volp); *outScpp = scp; return 0; } } /* now, if we don't have the fid, recycle something */ scp = cm_GetNewSCache(); osi_assert(!(scp->flags & CM_SCACHEFLAG_INHASH)); scp->fid = *fidp; scp->volp = volp; /* a held reference */ /* if this scache entry represents a volume root then we need * to copy the dotdotFipd from the volume structure where the * "master" copy is stored (defect 11489) */ if(scp->fid.vnode == 1 && scp->fid.unique == 1 && volp->dotdotFidp) { if (scp->dotdotFidp == (cm_fid_t *) NULL) scp->dotdotFidp = (cm_fid_t *) malloc(sizeof(cm_fid_t)); *(scp->dotdotFidp) = *volp->dotdotFidp; } if (volp->roID == fidp->volume) scp->flags |= (CM_SCACHEFLAG_PURERO | CM_SCACHEFLAG_RO); else if (volp->bkID == fidp->volume) scp->flags |= CM_SCACHEFLAG_RO; scp->nextp = cm_hashTablep[hash]; cm_hashTablep[hash] = scp; scp->flags |= CM_SCACHEFLAG_INHASH; scp->refCount = 1; lock_ReleaseWrite(&cm_scacheLock); /* now we have a held scache entry; just return it */ *outScpp = scp; return 0; } /* synchronize a fetch, store, read, write, fetch status or store status. * Called with scache mutex held, and returns with it held, but temporarily * drops it during the fetch. * * At most one flag can be on in flags, if this is an RPC request. * * Also, if we're fetching or storing data, we must ensure that we have a buffer. * * There are a lot of weird restrictions here; here's an attempt to explain the * rationale for the concurrency restrictions implemented in this function. * * First, although the file server will break callbacks when *another* machine * modifies a file or status block, the client itself is responsible for * concurrency control on its own requests. Callback breaking events are rare, * and simply invalidate any concurrent new status info. * * In the absence of callback breaking messages, we need to know how to * synchronize incoming responses describing updates to files. We synchronize * operations that update the data version by comparing the data versions. * However, updates that do not update the data, but only the status, can't be * synchronized with fetches or stores, since there's nothing to compare * to tell which operation executed first at the server. * * Thus, we can allow multiple ops that change file data, or dir data, and * fetches. However, status storing ops have to be done serially. * * Furthermore, certain data-changing ops are incompatible: we can't read or * write a buffer while doing a truncate. We can't read and write the same * buffer at the same time, or write while fetching or storing, or read while * fetching a buffer (this may change). We can't fetch and store at the same * time, either. * * With respect to status, we can't read and write at the same time, read while * fetching, write while fetching or storing, or fetch and store at the same time. * * We can't allow a get callback RPC to run in concurrently with something that * will return updated status, since we could start a call, have the server * return status, have another machine make an update to the status (which * doesn't change serverModTime), have the original machine get a new callback, * and then have the original machine merge in the early, old info from the * first call. At this point, the easiest way to avoid this problem is to have * getcallback calls conflict with all others for the same vnode. Other calls * to cm_MergeStatus that aren't associated with calls to cm_SyncOp on the same * vnode must be careful not to merge in their status unless they have obtained * a callback from the start of their call. * * Note added 1/23/96 * Concurrent StoreData RPC's can cause trouble if the file is being extended. * Each such RPC passes a FileLength parameter, which the server uses to do * pre-truncation if necessary. So if two RPC's are processed out of order at * the server, the one with the smaller FileLength will be processed last, * possibly resulting in a bogus truncation. The simplest way to avoid this * is to serialize all StoreData RPC's. This is the reason we defined * CM_SCACHESYNC_STOREDATA_EXCL and CM_SCACHEFLAG_DATASTORING. */ long cm_SyncOp(cm_scache_t *scp, cm_buf_t *bufp, cm_user_t *up, cm_req_t *reqp, long rights, long flags) { osi_queueData_t *qdp; long code; cm_buf_t *tbufp; long outRights; int bufLocked; /* lookup this first */ bufLocked = flags & CM_SCACHESYNC_BUFLOCKED; /* some minor assertions */ if (flags & (CM_SCACHESYNC_STOREDATA | CM_SCACHESYNC_FETCHDATA | CM_SCACHESYNC_READ | CM_SCACHESYNC_WRITE | CM_SCACHESYNC_SETSIZE)) { if (bufp) { osi_assert(bufp->refCount > 0); /* osi_assert(cm_FidCmp(&bufp->fid, &scp->fid) == 0); */ } } else osi_assert(bufp == NULL); /* Do the access check. Now we don't really do the access check * atomically, since the caller doesn't expect the parent dir to be * returned locked, and that is what we'd have to do to prevent a * callback breaking message on the parent due to a setacl call from * being processed while we're running. So, instead, we check things * here, and if things look fine with the access, we proceed to finish * the rest of this check. Sort of a hack, but probably good enough. */ while (1) { if (flags & CM_SCACHESYNC_FETCHSTATUS) { /* if we're bringing in a new status block, ensure that * we aren't already doing so, and that no one is * changing the status concurrently, either. We need * to do this, even if the status is of a different * type, since we don't have the ability to figure out, * in the AFS 3 protocols, which status-changing * operation ran first, or even which order a read and * a write occurred in. */ if (scp->flags & (CM_SCACHEFLAG_FETCHING | CM_SCACHEFLAG_STORING | CM_SCACHEFLAG_SIZESTORING | CM_SCACHEFLAG_GETCALLBACK)) goto sleep; } if (flags & (CM_SCACHESYNC_STORESIZE | CM_SCACHESYNC_STORESTATUS | CM_SCACHESYNC_SETSIZE | CM_SCACHESYNC_GETCALLBACK)) { /* if we're going to make an RPC to change the status, make sure * that no one is bringing in or sending out the status. */ if (scp->flags & (CM_SCACHEFLAG_FETCHING | CM_SCACHEFLAG_STORING | CM_SCACHEFLAG_SIZESTORING | CM_SCACHEFLAG_GETCALLBACK)) goto sleep; if (scp->bufReadsp || scp->bufWritesp) goto sleep; } if (flags & CM_SCACHESYNC_FETCHDATA) { /* if we're bringing in a new chunk of data, make sure that * nothing is happening to that chunk, and that we aren't * changing the basic file status info, either. */ if (scp->flags & (CM_SCACHEFLAG_FETCHING | CM_SCACHEFLAG_STORING | CM_SCACHEFLAG_SIZESTORING | CM_SCACHEFLAG_GETCALLBACK)) goto sleep; if (bufp && (bufp->cmFlags & (CM_BUF_CMFETCHING | CM_BUF_CMSTORING))) goto sleep; } if (flags & CM_SCACHESYNC_STOREDATA) { /* same as fetch data */ if (scp->flags & (CM_SCACHEFLAG_FETCHING | CM_SCACHEFLAG_STORING | CM_SCACHEFLAG_SIZESTORING | CM_SCACHEFLAG_GETCALLBACK)) goto sleep; if (bufp && (bufp->cmFlags & (CM_BUF_CMFETCHING | CM_BUF_CMSTORING))) goto sleep; } if (flags & CM_SCACHESYNC_STOREDATA_EXCL) { /* Don't allow concurrent StoreData RPC's */ if (scp->flags & CM_SCACHEFLAG_DATASTORING) goto sleep; } if (flags & CM_SCACHESYNC_ASYNCSTORE) { /* Don't allow more than one BKG store request */ if (scp->flags & CM_SCACHEFLAG_ASYNCSTORING) goto sleep; } if (flags & CM_SCACHESYNC_LOCK) { /* Don't allow concurrent fiddling with lock lists */ if (scp->flags & CM_SCACHEFLAG_LOCKING) goto sleep; } /* now the operations that don't correspond to making RPCs */ if (flags & CM_SCACHESYNC_GETSTATUS) { /* we can use the status that's here, if we're not * bringing in new status. */ if (scp->flags & (CM_SCACHEFLAG_FETCHING)) goto sleep; } if (flags & CM_SCACHESYNC_SETSTATUS) { /* we can make a change to the local status, as long as * the status isn't changing now. * * If we're fetching or storing a chunk of data, we can * change the status locally, since the fetch/store * operations don't change any of the data that we're * changing here. */ if (scp->flags & (CM_SCACHEFLAG_FETCHING | CM_SCACHEFLAG_STORING | CM_SCACHEFLAG_SIZESTORING)) goto sleep; } if (flags & CM_SCACHESYNC_READ) { /* we're going to read the data, make sure that the * status is available, and that the data is here. It * is OK to read while storing the data back. */ if (scp->flags & CM_SCACHEFLAG_FETCHING) goto sleep; if (bufp && ((bufp->cmFlags & (CM_BUF_CMFETCHING | CM_BUF_CMFULLYFETCHED)) == CM_BUF_CMFETCHING)) goto sleep; } if (flags & CM_SCACHESYNC_WRITE) { /* don't write unless the status is stable and the chunk * is stable. */ if (scp->flags & (CM_SCACHEFLAG_FETCHING | CM_SCACHEFLAG_STORING | CM_SCACHEFLAG_SIZESTORING)) goto sleep; if (bufp && (bufp->cmFlags & (CM_BUF_CMFETCHING | CM_BUF_CMSTORING))) goto sleep; } if (flags & CM_SCACHESYNC_NEEDCALLBACK) { if (!cm_HaveCallback(scp)) { osi_Log1(afsd_logp, "CM SyncOp getting callback on scp %x", (long) scp); if (bufLocked) lock_ReleaseMutex(&bufp->mx); code = cm_GetCallback(scp, up, reqp, 0); if (bufLocked) { lock_ReleaseMutex(&scp->mx); lock_ObtainMutex(&bufp->mx); lock_ObtainMutex(&scp->mx); } if (code) return code; continue; } } if (rights) { /* can't check access rights without a callback */ osi_assert(flags & CM_SCACHESYNC_NEEDCALLBACK); if ((rights & PRSFS_WRITE) && (scp->flags & CM_SCACHEFLAG_RO)) return CM_ERROR_READONLY; if (cm_HaveAccessRights(scp, up, rights, &outRights)) { if (~outRights & rights) return CM_ERROR_NOACCESS; } else { /* we don't know the required access rights */ if (bufLocked) lock_ReleaseMutex(&bufp->mx); code = cm_GetAccessRights(scp, up, reqp); if (code) return code; if (bufLocked) { lock_ReleaseMutex(&scp->mx); lock_ObtainMutex(&bufp->mx); lock_ObtainMutex(&scp->mx); } continue; } } /* if we get here, we're happy */ break; sleep: /* first check if we're not supposed to wait: fail * in this case, returning with everything still locked. */ if (flags & CM_SCACHESYNC_NOWAIT) return CM_ERROR_WOULDBLOCK; /* wait here, then try again */ osi_Log1(afsd_logp, "CM SyncOp sleeping scp %x", (long) scp); scp->flags |= CM_SCACHEFLAG_WAITING; if (bufLocked) lock_ReleaseMutex(&bufp->mx); osi_SleepM((long) &scp->flags, &scp->mx); osi_Log0(afsd_logp, "CM SyncOp woke!"); if (bufLocked) lock_ObtainMutex(&bufp->mx); lock_ObtainMutex(&scp->mx); } /* big while loop */ /* now, update the recorded state for RPC-type calls */ if (flags & CM_SCACHESYNC_FETCHSTATUS) scp->flags |= CM_SCACHEFLAG_FETCHING; if (flags & CM_SCACHESYNC_STORESTATUS) scp->flags |= CM_SCACHEFLAG_STORING; if (flags & CM_SCACHESYNC_STORESIZE) scp->flags |= CM_SCACHEFLAG_SIZESTORING; if (flags & CM_SCACHESYNC_GETCALLBACK) scp->flags |= CM_SCACHEFLAG_GETCALLBACK; if (flags & CM_SCACHESYNC_STOREDATA_EXCL) scp->flags |= CM_SCACHEFLAG_DATASTORING; if (flags & CM_SCACHESYNC_ASYNCSTORE) scp->flags |= CM_SCACHEFLAG_ASYNCSTORING; if (flags & CM_SCACHESYNC_LOCK) scp->flags |= CM_SCACHEFLAG_LOCKING; /* now update the buffer pointer */ if (flags & CM_SCACHESYNC_FETCHDATA) { /* ensure that the buffer isn't already in the I/O list */ if (bufp) { for(qdp = scp->bufReadsp; qdp; qdp = (osi_queueData_t *) osi_QNext(&qdp->q)) { tbufp = osi_GetQData(qdp); osi_assert(tbufp != bufp); } } /* queue a held reference to the buffer in the "reading" I/O list */ qdp = osi_QDAlloc(); osi_SetQData(qdp, bufp); if (bufp) { buf_Hold(bufp); bufp->cmFlags |= CM_BUF_CMFETCHING; } osi_QAdd((osi_queue_t **) &scp->bufReadsp, &qdp->q); } if (flags & CM_SCACHESYNC_STOREDATA) { /* ensure that the buffer isn't already in the I/O list */ if (bufp) { for(qdp = scp->bufWritesp; qdp; qdp = (osi_queueData_t *) osi_QNext(&qdp->q)) { tbufp = osi_GetQData(qdp); osi_assert(tbufp != bufp); } } /* queue a held reference to the buffer in the "writing" I/O list */ qdp = osi_QDAlloc(); osi_SetQData(qdp, bufp); if (bufp) { buf_Hold(bufp); bufp->cmFlags |= CM_BUF_CMSTORING; } osi_QAdd((osi_queue_t **) &scp->bufWritesp, &qdp->q); } return 0; } /* for those syncops that setup for RPCs. * Called with scache locked. */ void cm_SyncOpDone(cm_scache_t *scp, cm_buf_t *bufp, long flags) { osi_queueData_t *qdp; cm_buf_t *tbufp; /* now, update the recorded state for RPC-type calls */ if (flags & CM_SCACHESYNC_FETCHSTATUS) scp->flags &= ~CM_SCACHEFLAG_FETCHING; if (flags & CM_SCACHESYNC_STORESTATUS) scp->flags &= ~CM_SCACHEFLAG_STORING; if (flags & CM_SCACHESYNC_STORESIZE) scp->flags &= ~CM_SCACHEFLAG_SIZESTORING; if (flags & CM_SCACHESYNC_GETCALLBACK) scp->flags &= ~CM_SCACHEFLAG_GETCALLBACK; if (flags & CM_SCACHESYNC_STOREDATA_EXCL) scp->flags &= ~CM_SCACHEFLAG_DATASTORING; if (flags & CM_SCACHESYNC_ASYNCSTORE) scp->flags &= ~CM_SCACHEFLAG_ASYNCSTORING; if (flags & CM_SCACHESYNC_LOCK) scp->flags &= ~CM_SCACHEFLAG_LOCKING; /* now update the buffer pointer */ if (flags & CM_SCACHESYNC_FETCHDATA) { /* ensure that the buffer isn't already in the I/O list */ for(qdp = scp->bufReadsp; qdp; qdp = (osi_queueData_t *) osi_QNext(&qdp->q)) { tbufp = osi_GetQData(qdp); if (tbufp == bufp) break; } osi_assert(qdp != NULL); osi_assert(osi_GetQData(qdp) == bufp); osi_QRemove((osi_queue_t **) &scp->bufReadsp, &qdp->q); osi_QDFree(qdp); if (bufp) { bufp->cmFlags &= ~(CM_BUF_CMFETCHING | CM_BUF_CMFULLYFETCHED); buf_Release(bufp); } } /* now update the buffer pointer */ if (flags & CM_SCACHESYNC_STOREDATA) { /* ensure that the buffer isn't already in the I/O list */ for(qdp = scp->bufWritesp; qdp; qdp = (osi_queueData_t *) osi_QNext(&qdp->q)) { tbufp = osi_GetQData(qdp); if (tbufp == bufp) break; } osi_assert(qdp != NULL); osi_assert(osi_GetQData(qdp) == bufp); osi_QRemove((osi_queue_t **) &scp->bufWritesp, &qdp->q); osi_QDFree(qdp); if (bufp) { bufp->cmFlags &= ~CM_BUF_CMSTORING; buf_Release(bufp); } } /* and wakeup anyone who is waiting */ if (scp->flags & CM_SCACHEFLAG_WAITING) { scp->flags &= ~CM_SCACHEFLAG_WAITING; osi_Wakeup((long) &scp->flags); } } /* merge in a response from an RPC. The scp must be locked, and the callback * is optional. * * Don't overwrite any status info that is dirty, since we could have a store * operation (such as store data) that merges some info in, and we don't want * to lose the local updates. Typically, there aren't many updates we do * locally, anyway, probably only mtime. * * There is probably a bug in here where a chmod (which doesn't change * serverModTime) that occurs between two fetches, both of whose responses are * handled after the callback breaking is done, but only one of whose calls * started before that, can cause old info to be merged from the first call. */ void cm_MergeStatus(cm_scache_t *scp, AFSFetchStatus *statusp, AFSVolSync *volp, cm_user_t *userp, int flags) { if (!(flags & CM_MERGEFLAG_FORCE) && statusp->DataVersion < (unsigned long) scp->dataVersion) { struct cm_cell *cellp; struct cm_volume *volp; cellp = cm_FindCellByID(scp->fid.cell); cm_GetVolumeByID(cellp, scp->fid.volume, userp, (cm_req_t *) NULL, &volp); if (scp->cbServerp) osi_Log2(afsd_logp, "old data from server %x volume %s", scp->cbServerp->addr.sin_addr.s_addr, volp->namep); osi_Log3(afsd_logp, "Bad merge, scp %x, scp dv %d, RPC dv %d", scp, scp->dataVersion, statusp->DataVersion); /* we have a number of data fetch/store operations running * concurrently, and we can tell which one executed last at the * server by its mtime. * Choose the one with the largest mtime, and ignore the rest. * * These concurrent calls are incompatible with setting the * mtime, so we won't have a locally changed mtime here. * * We could also have ACL info for a different user than usual, * in which case we have to do that part of the merge, anyway. * We won't have to worry about the info being old, since we * won't have concurrent calls * that change file status running from this machine. * * Added 3/17/98: if we see data version regression on an RO * file, it's probably due to a server holding an out-of-date * replica, rather than to concurrent RPC's. Failures to * release replicas are now flagged by the volserver, but only * since AFS 3.4 5.22, so there are plenty of clients getting * out-of-date replicas out there. * * If we discover an out-of-date replica, by this time it's too * late to go to another server and retry. Also, we can't * reject the merge, because then there is no way for * GetAccess to do its work, and the caller gets into an * infinite loop. So we just grin and bear it. */ if (!(scp->flags & CM_SCACHEFLAG_RO)) return; } scp->serverModTime = statusp->ServerModTime; if (!(scp->mask & CM_SCACHEMASK_CLIENTMODTIME)) { scp->clientModTime = statusp->ClientModTime; } if (!(scp->mask & CM_SCACHEMASK_LENGTH)) { scp->length.LowPart = statusp->Length; scp->length.HighPart = 0; } scp->serverLength.LowPart = statusp->Length; scp->serverLength.HighPart = 0; scp->linkCount = statusp->LinkCount; scp->dataVersion = statusp->DataVersion; scp->owner = statusp->Owner; scp->group = statusp->Group; scp->unixModeBits = statusp->UnixModeBits & 07777; if (statusp->FileType == File) scp->fileType = CM_SCACHETYPE_FILE; else if (statusp->FileType == Directory) scp->fileType = CM_SCACHETYPE_DIRECTORY; else if (statusp->FileType == SymbolicLink) { if ((scp->unixModeBits & 0111) == 0) scp->fileType = CM_SCACHETYPE_MOUNTPOINT; else scp->fileType = CM_SCACHETYPE_SYMLINK; } else scp->fileType = 0; /* invalid */ /* and other stuff */ scp->parentVnode = statusp->ParentVnode; scp->parentUnique = statusp->ParentUnique; /* and merge in the private acl cache info, if this is more than the public * info; merge in the public stuff in any case. */ scp->anyAccess = statusp->AnonymousAccess; if (userp != NULL) { cm_AddACLCache(scp, userp, statusp->CallerAccess); } } /* note that our stat cache info is incorrect, so force us eventually * to stat the file again. There may be dirty data associated with * this vnode, and we want to preserve that information. * * This function works by simply simulating a loss of the callback. * * This function must be called with the scache locked. */ void cm_DiscardSCache(cm_scache_t *scp) { lock_AssertMutex(&scp->mx); scp->cbServerp = NULL; scp->cbExpires = 0; cm_dnlcPurgedp(scp); cm_FreeAllACLEnts(scp); } void cm_AFSFidFromFid(AFSFid *afsFidp, cm_fid_t *fidp) { afsFidp->Volume = fidp->volume; afsFidp->Vnode = fidp->vnode; afsFidp->Unique = fidp->unique; } void cm_HoldSCache(cm_scache_t *scp) { lock_ObtainWrite(&cm_scacheLock); osi_assert(scp->refCount > 0); scp->refCount++; lock_ReleaseWrite(&cm_scacheLock); } void cm_ReleaseSCache(cm_scache_t *scp) { lock_ObtainWrite(&cm_scacheLock); osi_assert(scp->refCount-- > 0); lock_ReleaseWrite(&cm_scacheLock); }