/* This function is silly anyway you look at it. * Think 2 concurrent threads trying to get a lock, that would use * this function to check if it is available to avoid blocking. * Accidents waiting to happen? */ int CheckLock(struct Lock *lock) { if (lock->readers) return lock->readers; if (WriteLocked(lock)) return -1; return 0; }
int afs_InvalidateAllSegments(struct vcache *avc) { struct dcache *tdc; afs_int32 hash; afs_int32 index; struct dcache **dcList; int i, dcListMax, dcListCount; AFS_STATCNT(afs_InvalidateAllSegments); afs_Trace2(afs_iclSetp, CM_TRACE_INVALL, ICL_TYPE_POINTER, avc, ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(avc->f.m.Length)); hash = DVHash(&avc->f.fid); avc->f.truncPos = AFS_NOTRUNC; /* don't truncate later */ avc->f.states &= ~CExtendedFile; /* not any more */ ObtainWriteLock(&afs_xcbhash, 459); afs_DequeueCallback(avc); avc->f.states &= ~(CStatd | CDirty); /* mark status information as bad, too */ ReleaseWriteLock(&afs_xcbhash); if (avc->f.fid.Fid.Vnode & 1 || (vType(avc) == VDIR)) osi_dnlc_purgedp(avc); /* Blow away pages; for now, only for Solaris */ #if (defined(AFS_SUN5_ENV)) if (WriteLocked(&avc->lock)) osi_ReleaseVM(avc, (afs_ucred_t *)0); #endif /* * Block out others from screwing with this table; is a read lock * sufficient? */ ObtainWriteLock(&afs_xdcache, 286); dcListMax = 0; for (index = afs_dvhashTbl[hash]; index != NULLIDX;) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetValidDSlot(index); if (!tdc) { /* In the case of fatal errors during stores, we MUST * invalidate all of the relevant chunks. Otherwise, the chunks * will be left with the 'new' data that was never successfully * written to the server, but the DV in the dcache is still the * old DV. So, we may indefinitely serve data to applications * that is not actually in the file on the fileserver. If we * cannot afs_GetValidDSlot the appropriate entries, currently * there is no way to ensure the dcache is invalidated. So for * now, to avoid risking serving bad data from the cache, panic * instead. */ osi_Panic("afs_InvalidateAllSegments tdc count"); } ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid)) dcListMax++; afs_PutDCache(tdc); } index = afs_dvnextTbl[index]; } dcList = osi_Alloc(dcListMax * sizeof(struct dcache *)); dcListCount = 0; for (index = afs_dvhashTbl[hash]; index != NULLIDX;) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetValidDSlot(index); if (!tdc) { /* We cannot proceed after getting this error; we risk serving * incorrect data to applications. So panic instead. See the * above comment next to the previous afs_GetValidDSlot call * for details. */ osi_Panic("afs_InvalidateAllSegments tdc store"); } ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid)) { /* same file? we'll zap it */ if (afs_indexFlags[index] & IFDataMod) { afs_stats_cmperf.cacheCurrDirtyChunks--; /* don't write it back */ afs_indexFlags[index] &= ~IFDataMod; } afs_indexFlags[index] &= ~IFAnyPages; if (dcListCount < dcListMax) dcList[dcListCount++] = tdc; else afs_PutDCache(tdc); } else { afs_PutDCache(tdc); } } index = afs_dvnextTbl[index]; } ReleaseWriteLock(&afs_xdcache); for (i = 0; i < dcListCount; i++) { tdc = dcList[i]; ObtainWriteLock(&tdc->lock, 679); ZapDCE(tdc); if (vType(avc) == VDIR) DZap(tdc); ReleaseWriteLock(&tdc->lock); afs_PutDCache(tdc); } osi_Free(dcList, dcListMax * sizeof(struct dcache *)); return 0; }
/* Note that we don't set CDirty here, this is OK because the unlink * RPC is called synchronously */ int afs_remove(OSI_VC_DECL(adp), char *aname, afs_ucred_t *acred) { struct vrequest treq; register struct dcache *tdc; struct VenusFid unlinkFid; register afs_int32 code; register struct vcache *tvc; afs_size_t offset, len; struct afs_fakestat_state fakestate; OSI_VC_CONVERT(adp); AFS_STATCNT(afs_remove); afs_Trace2(afs_iclSetp, CM_TRACE_REMOVE, ICL_TYPE_POINTER, adp, ICL_TYPE_STRING, aname); if ((code = afs_InitReq(&treq, acred))) { return code; } afs_InitFakeStat(&fakestate); AFS_DISCON_LOCK(); code = afs_EvalFakeStat(&adp, &fakestate, &treq); if (code) goto done; /* Check if this is dynroot */ if (afs_IsDynroot(adp)) { code = afs_DynrootVOPRemove(adp, acred, aname); goto done; } if (afs_IsDynrootMount(adp)) { code = ENOENT; goto done; } if (strlen(aname) > AFSNAMEMAX) { code = ENAMETOOLONG; goto done; } tagain: code = afs_VerifyVCache(adp, &treq); tvc = NULL; if (code) { code = afs_CheckCode(code, &treq, 23); goto done; } /** If the volume is read-only, return error without making an RPC to the * fileserver */ if (adp->f.states & CRO) { code = EROFS; goto done; } /* If we're running disconnected without logging, go no further... */ if (AFS_IS_DISCONNECTED && !AFS_IS_DISCON_RW) { code = ENETDOWN; goto done; } tdc = afs_GetDCache(adp, (afs_size_t) 0, &treq, &offset, &len, 1); /* test for error below */ ObtainWriteLock(&adp->lock, 142); if (tdc) ObtainSharedLock(&tdc->lock, 638); /* * Make sure that the data in the cache is current. We may have * received a callback while we were waiting for the write lock. */ if (!(adp->f.states & CStatd) || (tdc && !hsame(adp->f.m.DataVersion, tdc->f.versionNo))) { ReleaseWriteLock(&adp->lock); if (tdc) { ReleaseSharedLock(&tdc->lock); afs_PutDCache(tdc); } goto tagain; } unlinkFid.Fid.Vnode = 0; if (!tvc) { tvc = osi_dnlc_lookup(adp, aname, WRITE_LOCK); } /* This should not be necessary since afs_lookup() has already * done the work. */ if (!tvc) if (tdc) { code = afs_dir_Lookup(tdc, aname, &unlinkFid.Fid); if (code == 0) { afs_int32 cached = 0; unlinkFid.Cell = adp->f.fid.Cell; unlinkFid.Fid.Volume = adp->f.fid.Fid.Volume; if (unlinkFid.Fid.Unique == 0) { tvc = afs_LookupVCache(&unlinkFid, &treq, &cached, adp, aname); } else { ObtainReadLock(&afs_xvcache); tvc = afs_FindVCache(&unlinkFid, 0, DO_STATS); ReleaseReadLock(&afs_xvcache); } } } if (AFS_IS_DISCON_RW) { if (!adp->f.shadow.vnode && !(adp->f.ddirty_flags & VDisconCreate)) { /* Make shadow copy of parent dir. */ afs_MakeShadowDir(adp, tdc); } /* Can't hold a dcache lock whilst we're getting a vcache one */ if (tdc) ReleaseSharedLock(&tdc->lock); /* XXX - We're holding adp->lock still, and we've got no * guarantee about whether the ordering matches the lock hierarchy */ ObtainWriteLock(&tvc->lock, 713); /* If we were locally created, then we don't need to do very * much beyond ensuring that we don't exist anymore */ if (tvc->f.ddirty_flags & VDisconCreate) { afs_DisconRemoveDirty(tvc); } else { /* Add removed file vcache to dirty list. */ afs_DisconAddDirty(tvc, VDisconRemove, 1); } adp->f.m.LinkCount--; ReleaseWriteLock(&tvc->lock); if (tdc) ObtainSharedLock(&tdc->lock, 714); } if (tvc && osi_Active(tvc)) { /* about to delete whole file, prefetch it first */ ReleaseWriteLock(&adp->lock); if (tdc) ReleaseSharedLock(&tdc->lock); ObtainWriteLock(&tvc->lock, 143); FetchWholeEnchilada(tvc, &treq); ReleaseWriteLock(&tvc->lock); ObtainWriteLock(&adp->lock, 144); /* Technically I don't think we need this back, but let's hold it anyway; The "got" reference should actually be sufficient. */ if (tdc) ObtainSharedLock(&tdc->lock, 640); } osi_dnlc_remove(adp, aname, tvc); Tadp1 = adp; #ifndef AFS_DARWIN80_ENV Tadpr = VREFCOUNT(adp); #endif Ttvc = tvc; Tnam = aname; Tnam1 = 0; #ifndef AFS_DARWIN80_ENV if (tvc) Ttvcr = VREFCOUNT(tvc); #endif #ifdef AFS_AIX_ENV if (tvc && VREFCOUNT_GT(tvc, 2) && tvc->opens > 0 && !(tvc->f.states & CUnlinked)) { #else if (tvc && VREFCOUNT_GT(tvc, 1) && tvc->opens > 0 && !(tvc->f.states & CUnlinked)) { #endif char *unlname = afs_newname(); ReleaseWriteLock(&adp->lock); if (tdc) ReleaseSharedLock(&tdc->lock); code = afsrename(adp, aname, adp, unlname, acred, &treq); Tnam1 = unlname; if (!code) { struct VenusFid *oldmvid = NULL; if (tvc->mvid) oldmvid = tvc->mvid; tvc->mvid = (struct VenusFid *)unlname; if (oldmvid) osi_FreeSmallSpace(oldmvid); crhold(acred); if (tvc->uncred) { crfree(tvc->uncred); } tvc->uncred = acred; tvc->f.states |= CUnlinked; /* if rename succeeded, remove should not */ ObtainWriteLock(&tvc->lock, 715); if (tvc->f.ddirty_flags & VDisconRemove) { tvc->f.ddirty_flags &= ~VDisconRemove; } ReleaseWriteLock(&tvc->lock); } else { osi_FreeSmallSpace(unlname); } if (tdc) afs_PutDCache(tdc); afs_PutVCache(tvc); } else { code = afsremove(adp, tdc, tvc, aname, acred, &treq); } done: afs_PutFakeStat(&fakestate); #ifndef AFS_DARWIN80_ENV /* we can't track by thread, it's not exported in the KPI; only do this on !macos */ osi_Assert(!WriteLocked(&adp->lock) || (adp->lock.pid_writer != MyPidxx)); #endif AFS_DISCON_UNLOCK(); return code; } /* afs_remunlink -- This tries to delete the file at the server after it has * been renamed when unlinked locally but now has been finally released. * * CAUTION -- may be called with avc unheld. */ int afs_remunlink(register struct vcache *avc, register int doit) { afs_ucred_t *cred; char *unlname; struct vcache *adp; struct vrequest treq; struct VenusFid dirFid; register struct dcache *tdc; afs_int32 code = 0; if (NBObtainWriteLock(&avc->lock, 423)) return 0; #if defined(AFS_DARWIN80_ENV) if (vnode_get(AFSTOV(avc))) { ReleaseWriteLock(&avc->lock); return 0; } #endif if (avc->mvid && (doit || (avc->f.states & CUnlinkedDel))) { if ((code = afs_InitReq(&treq, avc->uncred))) { ReleaseWriteLock(&avc->lock); } else { /* Must bump the refCount because GetVCache may block. * Also clear mvid so no other thread comes here if we block. */ unlname = (char *)avc->mvid; avc->mvid = NULL; cred = avc->uncred; avc->uncred = NULL; #if defined(AFS_DARWIN_ENV) && !defined(AFS_DARWIN80_ENV) VREF(AFSTOV(avc)); #else AFS_FAST_HOLD(avc); #endif /* We'll only try this once. If it fails, just release the vnode. * Clear after doing hold so that NewVCache doesn't find us yet. */ avc->f.states &= ~(CUnlinked | CUnlinkedDel); ReleaseWriteLock(&avc->lock); dirFid.Cell = avc->f.fid.Cell; dirFid.Fid.Volume = avc->f.fid.Fid.Volume; dirFid.Fid.Vnode = avc->f.parent.vnode; dirFid.Fid.Unique = avc->f.parent.unique; adp = afs_GetVCache(&dirFid, &treq, NULL, NULL); if (adp) { tdc = afs_FindDCache(adp, (afs_size_t) 0); ObtainWriteLock(&adp->lock, 159); if (tdc) ObtainSharedLock(&tdc->lock, 639); /* afsremove releases the adp & tdc locks, and does vn_rele(avc) */ code = afsremove(adp, tdc, avc, unlname, cred, &treq); afs_PutVCache(adp); } else { /* we failed - and won't be back to try again. */ afs_PutVCache(avc); } osi_FreeSmallSpace(unlname); crfree(cred); } } else { #if defined(AFS_DARWIN80_ENV) vnode_put(AFSTOV(avc)); #endif ReleaseWriteLock(&avc->lock); } return code; }
void Recorder::WriteAtDestruction(serialization::Method const& method) { WriteLocked(method); lock_.Unlock(); }
void Recorder::WriteAtConstruction(serialization::Method const& method) { lock_.Lock(); WriteLocked(method); }
int afs_InvalidateAllSegments(struct vcache *avc) { struct dcache *tdc; afs_int32 hash; afs_int32 index; struct dcache **dcList; int i, dcListMax, dcListCount; AFS_STATCNT(afs_InvalidateAllSegments); afs_Trace2(afs_iclSetp, CM_TRACE_INVALL, ICL_TYPE_POINTER, avc, ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(avc->f.m.Length)); hash = DVHash(&avc->f.fid); avc->f.truncPos = AFS_NOTRUNC; /* don't truncate later */ avc->f.states &= ~CExtendedFile; /* not any more */ ObtainWriteLock(&afs_xcbhash, 459); afs_DequeueCallback(avc); avc->f.states &= ~(CStatd | CDirty); /* mark status information as bad, too */ ReleaseWriteLock(&afs_xcbhash); if (avc->f.fid.Fid.Vnode & 1 || (vType(avc) == VDIR)) osi_dnlc_purgedp(avc); /* Blow away pages; for now, only for Solaris */ #if (defined(AFS_SUN5_ENV)) if (WriteLocked(&avc->lock)) osi_ReleaseVM(avc, (afs_ucred_t *)0); #endif /* * Block out others from screwing with this table; is a read lock * sufficient? */ ObtainWriteLock(&afs_xdcache, 286); dcListMax = 0; for (index = afs_dvhashTbl[hash]; index != NULLIDX;) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetDSlot(index, 0); ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid)) dcListMax++; afs_PutDCache(tdc); } index = afs_dvnextTbl[index]; } dcList = osi_Alloc(dcListMax * sizeof(struct dcache *)); dcListCount = 0; for (index = afs_dvhashTbl[hash]; index != NULLIDX;) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetDSlot(index, 0); ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid)) { /* same file? we'll zap it */ if (afs_indexFlags[index] & IFDataMod) { afs_stats_cmperf.cacheCurrDirtyChunks--; /* don't write it back */ afs_indexFlags[index] &= ~IFDataMod; } afs_indexFlags[index] &= ~IFAnyPages; if (dcListCount < dcListMax) dcList[dcListCount++] = tdc; else afs_PutDCache(tdc); } else { afs_PutDCache(tdc); } } index = afs_dvnextTbl[index]; } ReleaseWriteLock(&afs_xdcache); for (i = 0; i < dcListCount; i++) { tdc = dcList[i]; ObtainWriteLock(&tdc->lock, 679); ZapDCE(tdc); if (vType(avc) == VDIR) DZap(tdc); ReleaseWriteLock(&tdc->lock); afs_PutDCache(tdc); } osi_Free(dcList, dcListMax * sizeof(struct dcache *)); return 0; }