stores: Allow reserving local storage

localworker.go

@@ -61,14 +61,22 @@ type localWorkerPathProvider struct {
 }
 
 func (l *localWorkerPathProvider) AcquireSector(ctx context.Context, sector abi.SectorID, existing stores.SectorFileType, allocate stores.SectorFileType, sealing stores.PathType) (stores.SectorPaths, func(), error) {
+
 	paths, storageIDs, err := l.w.storage.AcquireSector(ctx, sector, l.w.scfg.SealProofType, existing, allocate, sealing, l.op)
 	if err != nil {
 		return stores.SectorPaths{}, nil, err
 	}
 
+	releaseStorage, err := l.w.localStore.Reserve(ctx, sector, l.w.scfg.SealProofType, allocate, storageIDs, stores.FSOverheadSeal)
+	if err != nil {
+		return stores.SectorPaths{}, nil, xerrors.Errorf("reserving storage space: %w", err)
+	}
+
 	log.Debugf("acquired sector %d (e:%d; a:%d): %v", sector, existing, allocate, paths)
 
 	return paths, func() {
+		releaseStorage()
+
 		for _, fileType := range pathTypes {
 			if fileType&allocate == 0 {
 				continue

stores/filetype.go

@@ -19,15 +19,17 @@ const (
 	FTNone SectorFileType = 0
 )
 
+const FSOverheadDen = 10
+
 var FSOverheadSeal = map[SectorFileType]int{ // 10x overheads
-	FTUnsealed: 10,
-	FTSealed:   10,
+	FTUnsealed: FSOverheadDen,
+	FTSealed:   FSOverheadDen,
 	FTCache:    141, // 11 layers + D(2x ssize) + C + R
 }
 
 var FsOverheadFinalized = map[SectorFileType]int{
-	FTUnsealed: 10,
-	FTSealed:   10,
+	FTUnsealed: FSOverheadDen,
+	FTSealed:   FSOverheadDen,
 	FTCache:    2,
 }
 
@@ -67,7 +69,7 @@ func (t SectorFileType) SealSpaceUse(spt abi.RegisteredSealProof) (uint64, error
 			return 0, xerrors.Errorf("no seal overhead info for %s", pathType)
 		}
 
-		need += uint64(oh) * uint64(ssize) / 10
+		need += uint64(oh) * uint64(ssize) / FSOverheadDen
 	}
 
 	return need, nil

stores/http_handler.go

@@ -79,6 +79,8 @@ func (handler *FetchHandler) remoteGetSector(w http.ResponseWriter, r *http.Requ
 		return
 	}
 
+	// TODO: reserve local storage here
+
 	path := PathByType(paths, ft)
 	if path == "" {
 		log.Error("acquired path was empty")

stores/index.go

@@ -361,7 +361,7 @@ func (i *Index) StorageBestAlloc(ctx context.Context, allocate SectorFileType, s
 			continue
 		}
 
-		if spaceReq > p.fsi.Available {
+		if spaceReq > uint64(p.fsi.Available) {
 			log.Debugf("not allocating on %s, out of space (available: %d, need: %d)", p.info.ID, p.fsi.Available, spaceReq)
 			continue
 		}

stores/interface.go

@@ -44,13 +44,14 @@ func Stat(path string) (FsStat, error) {
 	}
 
 	return FsStat{
-		Capacity:  stat.Blocks * uint64(stat.Bsize),
-		Available: stat.Bavail * uint64(stat.Bsize),
+		Capacity:  int64(stat.Blocks) * stat.Bsize,
+		Available: int64(stat.Bavail) * stat.Bsize,
 	}, nil
 }
 
 type FsStat struct {
-	Capacity  uint64
-	Available uint64 // Available to use for sector storage
-	Used      uint64
+	Capacity  int64
+	Available int64 // Available to use for sector storage
+	Used      int64
+	Reserved  int64
 }

stores/local.go

@@ -67,6 +67,25 @@ type Local struct {
 
 type path struct {
 	local string // absolute local path
+
+	reserved int64
+	reservations map[abi.SectorID]SectorFileType
+}
+
+type statFn func(path string) (FsStat, error)
+func (p *path) stat(st statFn) (FsStat, error) {
+	stat, err := st(p.local)
+	if err != nil {
+		return FsStat{}, err
+	}
+
+	stat.Reserved = p.reserved
+	stat.Available -= p.reserved
+	if stat.Available < 0 {
+		stat.Available = 0
+	}
+
+	return stat, err
 }
 
 func NewLocal(ctx context.Context, ls LocalStorage, index SectorIndex, urls []string) (*Local, error) {
@@ -98,9 +117,12 @@ func (st *Local) OpenPath(ctx context.Context, p string) error {
 
 	out := &path{
 		local: p,
+
+		reserved: 0,
+		reservations: map[abi.SectorID]SectorFileType{},
 	}
 
-	fst, err := st.localStorage.Stat(p)
+	fst, err := out.stat(st.localStorage.Stat)
 	if err != nil {
 		return err
 	}
@@ -179,7 +201,7 @@ func (st *Local) reportHealth(ctx context.Context) {
 
 		toReport := map[ID]HealthReport{}
 		for id, p := range st.paths {
-			stat, err := st.localStorage.Stat(p.local)
+			stat, err := p.stat(st.localStorage.Stat)
 
 			toReport[id] = HealthReport{
 				Stat: stat,
@@ -197,6 +219,61 @@ func (st *Local) reportHealth(ctx context.Context) {
 	}
 }
 
+func (st *Local) Reserve(ctx context.Context, sid abi.SectorID, spt abi.RegisteredSealProof, ft SectorFileType, storageIDs SectorPaths, overheadTab map[SectorFileType]int) (func(), error) {
+	ssize, err := spt.SectorSize()
+	if err != nil {
+		return nil, xerrors.Errorf("getting sector size: %w", err)
+	}
+
+	st.localLk.Lock()
+
+	done := func(){}
+	deferredDone := func() { done() }
+	defer func() {
+		st.localLk.Unlock()
+		deferredDone()
+	}()
+
+	for _, fileType := range PathTypes {
+		if fileType&ft == 0 {
+			continue
+		}
+
+		id := ID(PathByType(storageIDs, fileType))
+
+		p, ok := st.paths[id]
+		if !ok {
+			return nil, errPathNotFound
+		}
+
+		stat, err := p.stat(st.localStorage.Stat)
+		if err != nil {
+			return nil, err
+		}
+
+		overhead := int64(overheadTab[fileType]) * int64(ssize) / FSOverheadDen
+
+		if stat.Available < overhead {
+			return nil, xerrors.Errorf("can't reserve %d bytes in '%s' (id:%s), only %d available", overhead, p.local, id, stat.Available)
+		}
+
+		p.reserved += overhead
+
+		prevDone := done
+		done = func() {
+			prevDone()
+
+			st.localLk.Lock()
+			defer st.localLk.Unlock()
+
+			p.reserved -= overhead
+		}
+	}
+
+	deferredDone = func() {}
+	return done, nil
+}
+
 func (st *Local) AcquireSector(ctx context.Context, sid abi.SectorID, spt abi.RegisteredSealProof, existing SectorFileType, allocate SectorFileType, pathType PathType, op AcquireMode) (SectorPaths, SectorPaths, error) {
 	if existing|allocate != existing^allocate {
 		return SectorPaths{}, SectorPaths{}, xerrors.New("can't both find and allocate a sector")
@@ -463,7 +540,7 @@ func (st *Local) FsStat(ctx context.Context, id ID) (FsStat, error) {
 		return FsStat{}, errPathNotFound
 	}
 
-	return st.localStorage.Stat(p.local)
+	return p.stat(st.localStorage.Stat)
 }
 
 var _ Store = &Local{}