/* * Copyright 2000, International Business Machines Corporation and others. * All Rights Reserved. * * This software has been released under the terms of the IBM Public * License. For details, see the LICENSE file in the top-level source * directory or online at http://www.openafs.org/dl/license10.html */ /* * --------------------- Required definitions --------------------- */ #include #include "afs/param.h" #include "afs/sysincludes.h" /*Standard vendor system headers */ #include "afsincludes.h" /*AFS-based standard headers */ #include "afs/afs_stats.h" /* statistics */ #include "afs/afs_cbqueue.h" #include "afs/afs_osidnlc.h" afs_uint32 afs_stampValue = 0; /* * afs_StoreMini * * Description: * Send a truncation request to a FileServer. * * Parameters: * xxx : description * * Environment: * We're write-locked upon entry. */ static int afs_StoreMini(struct vcache *avc, struct vrequest *areq) { struct afs_conn *tc; struct AFSStoreStatus InStatus; struct AFSFetchStatus OutStatus; struct AFSVolSync tsync; afs_int32 code; struct rx_call *tcall; struct rx_connection *rxconn; afs_size_t tlen, xlen = 0; XSTATS_DECLS; AFS_STATCNT(afs_StoreMini); afs_Trace2(afs_iclSetp, CM_TRACE_STOREMINI, ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, avc->f.m.Length); tlen = avc->f.m.Length; if (avc->f.truncPos < tlen) tlen = avc->f.truncPos; avc->f.truncPos = AFS_NOTRUNC; avc->f.states &= ~CExtendedFile; memset(&InStatus, 0, sizeof(InStatus)); do { tc = afs_Conn(&avc->f.fid, areq, SHARED_LOCK, &rxconn); if (tc) { #ifdef AFS_64BIT_CLIENT retry: #endif RX_AFS_GUNLOCK(); tcall = rx_NewCall(rxconn); RX_AFS_GLOCK(); /* Set the client mod time since we always want the file * to have the client's mod time and not the server's one * (to avoid problems with make, etc.) It almost always * works fine with standard afs because them server/client * times are in sync and more importantly this storemini * it's a special call that would typically be followed by * the proper store-data or store-status calls. */ InStatus.Mask = AFS_SETMODTIME; InStatus.ClientModTime = avc->f.m.Date; XSTATS_START_TIME(AFS_STATS_FS_RPCIDX_STOREDATA); afs_Trace4(afs_iclSetp, CM_TRACE_STOREDATA64, ICL_TYPE_FID, &avc->f.fid.Fid, ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(avc->f.m.Length), ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(xlen), ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(tlen)); RX_AFS_GUNLOCK(); #ifdef AFS_64BIT_CLIENT if (!afs_serverHasNo64Bit(tc)) { code = StartRXAFS_StoreData64(tcall, (struct AFSFid *)&avc->f.fid.Fid, &InStatus, avc->f.m.Length, (afs_size_t) 0, tlen); } else { afs_int32 l1, l2; l1 = avc->f.m.Length; l2 = tlen; if ((avc->f.m.Length > 0x7fffffff) || (tlen > 0x7fffffff) || ((0x7fffffff - tlen) < avc->f.m.Length)) { code = EFBIG; goto error; } code = StartRXAFS_StoreData(tcall, (struct AFSFid *)&avc->f.fid.Fid, &InStatus, l1, 0, l2); } #else /* AFS_64BIT_CLIENT */ code = StartRXAFS_StoreData(tcall, (struct AFSFid *)&avc->f.fid.Fid, &InStatus, avc->f.m.Length, 0, tlen); #endif /* AFS_64BIT_CLIENT */ if (code == 0) { code = EndRXAFS_StoreData(tcall, &OutStatus, &tsync); } #ifdef AFS_64BIT_CLIENT error: #endif code = rx_EndCall(tcall, code); RX_AFS_GLOCK(); XSTATS_END_TIME; #ifdef AFS_64BIT_CLIENT if (code == RXGEN_OPCODE && !afs_serverHasNo64Bit(tc)) { afs_serverSetNo64Bit(tc); goto retry; } #endif /* AFS_64BIT_CLIENT */ } else code = -1; } while (afs_Analyze (tc, rxconn, code, &avc->f.fid, areq, AFS_STATS_FS_RPCIDX_STOREDATA, SHARED_LOCK, NULL)); if (code == 0) afs_ProcessFS(avc, &OutStatus, areq); return code; } /*afs_StoreMini */ /* * afs_StoreAllSegments * * Description: * Stores all modified segments back to server * * Parameters: * avc : Pointer to vcache entry. * areq : Pointer to request structure. * * Environment: * Called with avc write-locked. */ #if defined (AFS_HPUX_ENV) int NCHUNKSATONCE = 3; #else int NCHUNKSATONCE = 64; #endif int afs_dvhack = 0; int afs_StoreAllSegments(struct vcache *avc, struct vrequest *areq, int sync) { struct dcache *tdc; afs_int32 code = 0; afs_int32 index; afs_int32 origCBs, foreign = 0; int hash; afs_hyper_t newDV, oldDV; /* DV when we start, and finish, respectively */ struct dcache **dcList; unsigned int i, j, minj, moredata, high, off; afs_size_t maxStoredLength; /* highest offset we've written to server. */ int safety, marineronce = 0; AFS_STATCNT(afs_StoreAllSegments); hash = DVHash(&avc->f.fid); foreign = (avc->f.states & CForeign); dcList = osi_AllocLargeSpace(AFS_LRALLOCSIZ); afs_Trace2(afs_iclSetp, CM_TRACE_STOREALL, ICL_TYPE_POINTER, avc, ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(avc->f.m.Length)); #if !defined(AFS_AIX32_ENV) && !defined(AFS_SGI_ENV) /* In the aix vm implementation we need to do the vm_writep even * on the memcache case since that's we adjust the file's size * and finish flushing partial vm pages. */ if ((sync & AFS_NOVMSYNC)) { /* noop */ } else if ((cacheDiskType != AFS_FCACHE_TYPE_MEM) || (sync & AFS_VMSYNC_INVAL) || (sync & AFS_VMSYNC) || (sync & AFS_LASTSTORE)) #endif /* !AFS_AIX32_ENV && !AFS_SGI_ENV */ { /* If we're not diskless, reading a file may stress the VM * system enough to cause a pageout, and this vnode would be * locked when the pageout occurs. We can prevent this problem * by making sure all dirty pages are already flushed. We don't * do this when diskless because reading a diskless (i.e. * memory-resident) chunk doesn't require using new VM, and we * also don't want to dump more dirty data into a diskless cache, * since they're smaller, and we might exceed its available * space. */ #if defined(AFS_SUN5_ENV) if (sync & AFS_VMSYNC_INVAL) /* invalidate VM pages */ osi_VM_TryToSmush(avc, CRED(), 1); else #endif osi_VM_StoreAllSegments(avc); } if (AFS_IS_DISCONNECTED && !AFS_IN_SYNC) { /* This will probably make someone sad ... */ /*printf("Net down in afs_StoreSegments\n");*/ return ENETDOWN; } /* * Can't do this earlier because osi_VM_StoreAllSegments drops locks * and can indirectly do some stores that increase the DV. */ hset(oldDV, avc->f.m.DataVersion); hset(newDV, avc->f.m.DataVersion); ConvertWToSLock(&avc->lock); /* * Subsequent code expects a sorted list, and it expects all the * chunks in the list to be contiguous, so we need a sort and a * while loop in here, too - but this will work for a first pass... * 92.10.05 - OK, there's a sort in here now. It's kind of a modified * bin sort, I guess. Chunk numbers start with 0 * * - Have to get a write lock on xdcache because GetDSlot might need it (if * the chunk doesn't have a dcache struct). * This seems like overkill in most cases. * - I'm not sure that it's safe to do "index = .hvNextp", then unlock * xdcache, then relock xdcache and try to use index. It is done * a lot elsewhere in the CM, but I'm not buying that argument. * - should be able to check IFDataMod without doing the GetDSlot (just * hold afs_xdcache). That way, it's easy to do this without the * writelock on afs_xdcache, and we save unneccessary disk * operations. I don't think that works, 'cuz the next pointers * are still on disk. */ origCBs = afs_allCBs; maxStoredLength = 0; minj = 0; do { memset(dcList, 0, NCHUNKSATONCE * sizeof(struct dcache *)); high = 0; moredata = FALSE; /* lock and start over from beginning of hash chain * in order to avoid a race condition. */ ObtainWriteLock(&afs_xdcache, 284); index = afs_dvhashTbl[hash]; for (j = 0; index != NULLIDX;) { if ((afs_indexFlags[index] & IFDataMod) && (afs_indexUnique[index] == avc->f.fid.Fid.Unique)) { tdc = afs_GetValidDSlot(index); /* refcount+1. */ if (!tdc) { ReleaseWriteLock(&afs_xdcache); code = EIO; goto done; } ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid) && tdc->f.chunk >= minj) { off = tdc->f.chunk - minj; if (off < NCHUNKSATONCE) { if (dcList[off]) osi_Panic("dclist slot already in use!"); if (afs_mariner && !marineronce) { /* first chunk only */ afs_MarinerLog("store$Storing", avc); marineronce++; } dcList[off] = tdc; if (off > high) high = off; j++; /* DCLOCKXXX: chunkBytes is protected by tdc->lock which we * can't grab here, due to lock ordering with afs_xdcache. * So, disable this shortcut for now. -- kolya 2001-10-13 */ /* shortcut: big win for little files */ /* tlen -= tdc->f.chunkBytes; * if (tlen <= 0) * break; */ } else { moredata = TRUE; afs_PutDCache(tdc); if (j == NCHUNKSATONCE) break; } } else { afs_PutDCache(tdc); } } index = afs_dvnextTbl[index]; } ReleaseWriteLock(&afs_xdcache); /* this guy writes chunks, puts back dcache structs, and bumps newDV */ /* "moredata" just says "there are more dirty chunks yet to come". */ if (j) { code = afs_CacheStoreVCache(dcList, avc, areq, sync, minj, high, moredata, &newDV, &maxStoredLength); /* Release any zero-length dcache entries in our interval * that we locked but didn't store back above. */ for (j = 0; j <= high; j++) { tdc = dcList[j]; if (tdc) { osi_Assert(tdc->f.chunkBytes == 0); ReleaseSharedLock(&tdc->lock); afs_PutDCache(tdc); } } } /* if (j) */ minj += NCHUNKSATONCE; } while (!code && moredata); done: UpgradeSToWLock(&avc->lock, 29); /* send a trivial truncation store if did nothing else */ if (code == 0) { /* * Call StoreMini if we haven't written enough data to extend the * file at the fileserver to the client's notion of the file length. */ if ((avc->f.truncPos != AFS_NOTRUNC) || ((avc->f.states & CExtendedFile) && (maxStoredLength < avc->f.m.Length))) { code = afs_StoreMini(avc, areq); if (code == 0) hadd32(newDV, 1); /* just bumped here, too */ } avc->f.states &= ~CExtendedFile; } /* * Finally, turn off DWriting, turn on DFEntryMod, * update f.versionNo. * A lot of this could be integrated into the loop above */ if (!code) { afs_hyper_t h_unset; hones(h_unset); minj = 0; do { moredata = FALSE; memset(dcList, 0, NCHUNKSATONCE * sizeof(struct dcache *)); /* overkill, but it gets the lock in case GetDSlot needs it */ ObtainWriteLock(&afs_xdcache, 285); for (j = 0, safety = 0, index = afs_dvhashTbl[hash]; index != NULLIDX && safety < afs_cacheFiles + 2; index = afs_dvnextTbl[index]) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetValidDSlot(index); if (!tdc) { /* This is okay; since manipulating the dcaches at this * point is best-effort. We only get a dcache here to * increment the dv and turn off DWriting. If we were * supposed to do that for a dcache, but could not * due to an I/O error, it just means the dv won't * be updated so we don't be able to use that cached * chunk in the future. That's inefficient, but not * an error. */ break; } ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid) && tdc->f.chunk >= minj) { off = tdc->f.chunk - minj; if (off < NCHUNKSATONCE) { /* this is the file, and the correct chunk range */ if (j >= NCHUNKSATONCE) osi_Panic ("Too many dcache entries in range\n"); dcList[j++] = tdc; } else { moredata = TRUE; afs_PutDCache(tdc); if (j == NCHUNKSATONCE) break; } } else { afs_PutDCache(tdc); } } } ReleaseWriteLock(&afs_xdcache); for (i = 0; i < j; i++) { /* Iterate over the dcache entries we collected above */ tdc = dcList[i]; ObtainSharedLock(&tdc->lock, 677); /* was code here to clear IFDataMod, but it should only be done * in storedcache and storealldcache. */ /* Only increase DV if we had up-to-date data to start with. * Otherwise, we could be falsely upgrading an old chunk * (that we never read) into one labelled with the current * DV #. Also note that we check that no intervening stores * occurred, otherwise we might mislabel cache information * for a chunk that we didn't store this time */ /* Don't update the version number if it's not yet set. */ if (!hsame(tdc->f.versionNo, h_unset) && hcmp(tdc->f.versionNo, oldDV) >= 0) { if ((!(afs_dvhack || foreign) && hsame(avc->f.m.DataVersion, newDV)) || ((afs_dvhack || foreign) && (origCBs == afs_allCBs))) { /* no error, this is the DV */ UpgradeSToWLock(&tdc->lock, 678); hset(tdc->f.versionNo, avc->f.m.DataVersion); tdc->dflags |= DFEntryMod; /* DWriting may not have gotten cleared above, if all * we did was a StoreMini */ tdc->f.states &= ~DWriting; ConvertWToSLock(&tdc->lock); } } ReleaseSharedLock(&tdc->lock); afs_PutDCache(tdc); } minj += NCHUNKSATONCE; } while (moredata); } if (code) { /* * Invalidate chunks after an error for ccores files since * afs_inactive won't be called for these and they won't be * invalidated. Also discard data if it's a permanent error from the * fileserver. */ if (areq->permWriteError || (avc->f.states & CCore)) { afs_InvalidateAllSegments(avc); } } afs_Trace3(afs_iclSetp, CM_TRACE_STOREALLDONE, ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, avc->f.m.Length, ICL_TYPE_INT32, code); /* would like a Trace5, but it doesn't exist... */ afs_Trace3(afs_iclSetp, CM_TRACE_AVCLOCKER, ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, avc->lock.wait_states, ICL_TYPE_INT32, avc->lock.excl_locked); afs_Trace4(afs_iclSetp, CM_TRACE_AVCLOCKEE, ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, avc->lock.wait_states, ICL_TYPE_INT32, avc->lock.readers_reading, ICL_TYPE_INT32, avc->lock.num_waiting); /* * Finally, if updated DataVersion matches newDV, we did all of the * stores. If mapDV indicates that the page cache was flushed up * to when we started the store, then we can relabel them as flushed * as recently as newDV. * Turn off CDirty bit because the stored data is now in sync with server. */ if (code == 0 && hcmp(avc->mapDV, oldDV) >= 0) { if ((!(afs_dvhack || foreign) && hsame(avc->f.m.DataVersion, newDV)) || ((afs_dvhack || foreign) && (origCBs == afs_allCBs))) { hset(avc->mapDV, newDV); avc->f.states &= ~CDirty; } } osi_FreeLargeSpace(dcList); /* If not the final write a temporary error is ok. */ if (code && !areq->permWriteError && !(sync & AFS_LASTSTORE)) code = 0; return code; } /*afs_StoreAllSegments (new 03/02/94) */ /*! * Attempt to invalidate all chunks for a given file. * * \pre avc->lock is write-locked * \pre afs_xdcache is not held * * \param avc vcache to invalidate segments for * \return errno-style error codes. when an error is returned, the caller must * retry the invalidation until successful (see comments in * afs_InvalidateAllSegments) */ int afs_InvalidateAllSegments_once(struct vcache *avc) { struct dcache *tdc; afs_int32 hash; afs_int32 index; struct dcache **dcList = NULL; int i, dcListMax, dcListCount = 0; 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)); osi_Assert(WriteLocked(&avc->lock)); hash = DVHash(&avc->f.fid); avc->f.truncPos = AFS_NOTRUNC; /* don't truncate later */ avc->f.states &= ~CExtendedFile; /* not any more */ afs_StaleVCacheFlags(avc, 0, CDirty); /* Blow away pages; for now, only for Solaris */ #if (defined(AFS_SUN5_ENV)) 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) { goto error; } 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 *)); for (index = afs_dvhashTbl[hash]; index != NULLIDX;) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetValidDSlot(index); if (!tdc) { goto error; } 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; error: ReleaseWriteLock(&afs_xdcache); if (dcList) { for (i = 0; i < dcListCount; i++) { tdc = dcList[i]; if (tdc) { afs_PutDCache(tdc); } } osi_Free(dcList, dcListMax * sizeof(struct dcache *)); } return EIO; } /* * afs_InvalidateAllSegments * * Description: * Invalidates all chunks for a given file * * Parameters: * avc : Pointer to vcache entry. * * Environment: * For example, called after an error has been detected. Called * with avc write-locked, and afs_xdcache unheld. */ void afs_InvalidateAllSegments(struct vcache *avc) { int code; afs_uint32 last_warn; code = afs_InvalidateAllSegments_once(avc); if (code == 0) { /* Success; nothing more to do. */ return; } /* * If afs_InvalidateAllSegments_once failed, we cannot simply return an * error to our caller. This function is called when we encounter a fatal * error during stores, in which case we MUST invalidate all chunks for the * given file. If we fail to invalidate some chunks, they will be left with * the 'new' dirty/written data that was never successfully stored on the * server, but the DV in the dcache is still the old DV. So, if its left * alone, we may indefinitely serve data to applications that is not * actually in the file on the fileserver. * * So to make sure we never serve userspace bad data after such a failure, * we must keep trying to invalidate the dcaches for the given file. (Note * that we cannot simply set a flag on the vcache to retry the invalidate * later on, because the vcache may go away, but the 'bad' dcaches could * remain.) We do this below, via background daemon requests because in * some scenarios we can always get I/O errors on accessing the cache if we * access via a user pid. (e.g. on LINUX, this can happen if the pid has a * pending SIGKILL.) Doing this via background daemon ops should avoid * that. */ last_warn = osi_Time(); afs_warn("afs: Failed to invalidate cache chunks for fid %d.%d.%d.%d; our " "local disk cache may be throwing errors. We must invalidate " "these chunks to avoid possibly serving incorrect data, so we'll " "retry until we succeed. If AFS access seems to hang, this may " "be why.\n", avc->f.fid.Cell, avc->f.fid.Fid.Volume, avc->f.fid.Fid.Vnode, avc->f.fid.Fid.Unique); do { static const afs_uint32 warn_int = 60*60; /* warn once every hour */ afs_uint32 now = osi_Time(); struct brequest *bp; if (now < last_warn || now - last_warn > warn_int) { last_warn = now; afs_warn("afs: Still trying to invalidate cache chunks for fid " "%d.%d.%d.%d. We will retry until we succeed; if AFS " "access seems to hang, this may be why.\n", avc->f.fid.Cell, avc->f.fid.Fid.Volume, avc->f.fid.Fid.Vnode, avc->f.fid.Fid.Unique); } /* Wait 10 seconds between attempts. */ afs_osi_Wait(1000 * 10, NULL, 0); /* * Ask a background daemon to do this request for us. Note that _we_ hold * the write lock on 'avc', while the background daemon does the work. This * is a little weird, but it helps avoid any issues with lock ordering * or if our caller does not expect avc->lock to be dropped while * running. */ bp = afs_BQueue(BOP_INVALIDATE_SEGMENTS, avc, 0, 1, NULL, 0, 0, NULL, NULL, NULL); while ((bp->flags & BUVALID) == 0) { bp->flags |= BUWAIT; afs_osi_Sleep(bp); } code = bp->code_raw; afs_BRelease(bp); } while (code); } /*! * * Extend a cache file * * \param avc pointer to vcache to extend data for * \param alen Length to extend file to * \param areq * * \note avc must be write locked. May release and reobtain avc and GLOCK */ int afs_ExtendSegments(struct vcache *avc, afs_size_t alen, struct vrequest *areq) { afs_size_t offset, toAdd; struct osi_file *tfile; afs_int32 code = 0; struct dcache *tdc; void *zeros; zeros = afs_osi_Alloc(AFS_PAGESIZE); if (zeros == NULL) return ENOMEM; memset(zeros, 0, AFS_PAGESIZE); while (avc->f.m.Length < alen) { tdc = afs_ObtainDCacheForWriting(avc, avc->f.m.Length, alen - avc->f.m.Length, areq, 0); if (!tdc) { code = EIO; break; } toAdd = alen - avc->f.m.Length; offset = avc->f.m.Length - AFS_CHUNKTOBASE(tdc->f.chunk); if (offset + toAdd > AFS_CHUNKTOSIZE(tdc->f.chunk)) { toAdd = AFS_CHUNKTOSIZE(tdc->f.chunk) - offset; } tfile = afs_CFileOpen(&tdc->f.inode); if (!tfile) { ReleaseWriteLock(&tdc->lock); afs_PutDCache(tdc); code = EIO; break; } while(tdc->validPos < avc->f.m.Length + toAdd) { afs_size_t towrite; towrite = (avc->f.m.Length + toAdd) - tdc->validPos; if (towrite > AFS_PAGESIZE) towrite = AFS_PAGESIZE; code = afs_CFileWrite(tfile, tdc->validPos - AFS_CHUNKTOBASE(tdc->f.chunk), zeros, towrite); tdc->validPos += towrite; } afs_CFileClose(tfile); afs_AdjustSize(tdc, offset + toAdd ); avc->f.m.Length += toAdd; ReleaseWriteLock(&tdc->lock); afs_PutDCache(tdc); } afs_osi_Free(zeros, AFS_PAGESIZE); return code; } /* * afs_TruncateAllSegments * * Description: * Truncate a cache file. * * Parameters: * avc : Ptr to vcache entry to truncate. * alen : Number of bytes to make the file. * areq : Ptr to request structure. * * Environment: * Called with avc write-locked; in VFS40 systems, pvnLock is also * held. */ int afs_TruncateAllSegments(struct vcache *avc, afs_size_t alen, struct vrequest *areq, afs_ucred_t *acred) { struct dcache *tdc; afs_int32 code; afs_int32 index; afs_size_t newSize; int dcCount, dcPos; struct dcache **tdcArray = NULL; AFS_STATCNT(afs_TruncateAllSegments); avc->f.m.Date = osi_Time(); afs_Trace3(afs_iclSetp, CM_TRACE_TRUNCALL, ICL_TYPE_POINTER, avc, ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(avc->f.m.Length), ICL_TYPE_OFFSET, ICL_HANDLE_OFFSET(alen)); if (alen >= avc->f.m.Length) { /* * Special speedup since Sun's vm extends the file this way; * we've never written to the file thus we can just set the new * length and avoid the needless calls below. * Also used for ftruncate calls which can extend the file. * To completely minimize the possible extra StoreMini RPC, we really * should keep the ExtendedPos as well and clear this flag if we * truncate below that value before we store the file back. */ avc->f.states |= CExtendedFile; avc->f.m.Length = alen; return 0; } #if (defined(AFS_SUN5_ENV)) /* Zero unused portion of last page */ osi_VM_PreTruncate(avc, alen, acred); #endif #if (defined(AFS_SUN5_ENV)) ObtainWriteLock(&avc->vlock, 546); avc->activeV++; /* Block new getpages */ ReleaseWriteLock(&avc->vlock); #endif ReleaseWriteLock(&avc->lock); AFS_GUNLOCK(); /* Flush pages beyond end-of-file. */ osi_VM_Truncate(avc, alen, acred); AFS_GLOCK(); ObtainWriteLock(&avc->lock, 79); avc->f.m.Length = alen; if (alen < avc->f.truncPos) avc->f.truncPos = alen; code = DVHash(&avc->f.fid); /* block out others from screwing with this table */ ObtainWriteLock(&afs_xdcache, 287); dcCount = 0; for (index = afs_dvhashTbl[code]; index != NULLIDX;) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetValidDSlot(index); if (!tdc) { ReleaseWriteLock(&afs_xdcache); code = EIO; goto done; } ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid)) dcCount++; afs_PutDCache(tdc); } index = afs_dvnextTbl[index]; } /* Now allocate space where we can save those dcache entries, and * do a second pass over them.. Since we're holding xdcache, it * shouldn't be changing. */ tdcArray = osi_Alloc(dcCount * sizeof(struct dcache *)); dcPos = 0; for (index = afs_dvhashTbl[code]; index != NULLIDX; index = afs_dvnextTbl[index]) { if (afs_indexUnique[index] == avc->f.fid.Fid.Unique) { tdc = afs_GetValidDSlot(index); if (!tdc) { /* make sure we put back all of the tdcArray members before * bailing out */ /* remember, the last valid tdc is at dcPos-1, so start at * dcPos-1, not at dcPos itself. */ for (dcPos = dcPos - 1; dcPos >= 0; dcPos--) { tdc = tdcArray[dcPos]; afs_PutDCache(tdc); } code = EIO; goto done; } ReleaseReadLock(&tdc->tlock); if (!FidCmp(&tdc->f.fid, &avc->f.fid)) { /* same file, and modified, we'll store it back */ if (dcPos < dcCount) { tdcArray[dcPos++] = tdc; } else { afs_PutDCache(tdc); } } else { afs_PutDCache(tdc); } } } ReleaseWriteLock(&afs_xdcache); /* Now we loop over the array of dcache entries and truncate them */ for (index = 0; index < dcPos; index++) { struct osi_file *tfile; tdc = tdcArray[index]; newSize = alen - AFS_CHUNKTOBASE(tdc->f.chunk); if (newSize < 0) newSize = 0; ObtainSharedLock(&tdc->lock, 672); if (newSize < tdc->f.chunkBytes && newSize < MAX_AFS_UINT32) { UpgradeSToWLock(&tdc->lock, 673); tdc->f.states |= DWriting; tfile = afs_CFileOpen(&tdc->f.inode); osi_Assert(tfile); afs_CFileTruncate(tfile, (afs_int32)newSize); afs_CFileClose(tfile); afs_AdjustSize(tdc, (afs_int32)newSize); if (alen < tdc->validPos) { if (alen < AFS_CHUNKTOBASE(tdc->f.chunk)) tdc->validPos = 0; else tdc->validPos = alen; } ConvertWToSLock(&tdc->lock); } ReleaseSharedLock(&tdc->lock); afs_PutDCache(tdc); } code = 0; done: if (tdcArray) { osi_Free(tdcArray, dcCount * sizeof(struct dcache *)); } #if (defined(AFS_SUN5_ENV)) ObtainWriteLock(&avc->vlock, 547); if (--avc->activeV == 0 && (avc->vstates & VRevokeWait)) { avc->vstates &= ~VRevokeWait; afs_osi_Wakeup((char *)&avc->vstates); } ReleaseWriteLock(&avc->vlock); #endif return code; }