Merge branch 'master' into raulk/itests

2021-06-07 23:44:22 +01:00 · 2021-06-07 23:44:22 +01:00 · a274fcc533
commit a274fcc533
parent db1a61852d fadc79a487
56 changed files with 3383 additions and 1422 deletions
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@ -331,7 +331,7 @@ jobs:
      - run: cd extern/filecoin-ffi && make
      - run:
          name: "go get lotus@master"
-          command: cd testplans/lotus-soup && go mod edit -replace=github.com/filecoin-project/lotus=../..
+          command: cd testplans/lotus-soup && go mod edit -replace=github.com/filecoin-project/lotus=../.. && go mod tidy
      - run:
          name: "build lotus-soup testplan"
          command: pushd testplans/lotus-soup && go build -tags=testground .
@ -565,6 +565,34 @@ jobs:
          name: Publish release
          command: ./scripts/publish-release.sh

+  publish-snapcraft:
+    description: build and push snapcraft
+    machine:
+      image: ubuntu-2004:202104-01
+    resource_class: 2xlarge
+    parameters:
+      channel:
+        type: string
+        default: "edge"
+        description: snapcraft channel
+    steps:
+      - checkout
+      - run:
+          name: install snapcraft
+          command: sudo snap install snapcraft --classic
+      - run:
+          name: create snapcraft config file
+          command: |
+            mkdir -p ~/.config/snapcraft
+            echo "$SNAPCRAFT_LOGIN_FILE" | base64 -d > ~/.config/snapcraft/snapcraft.cfg
+      - run:
+          name: build snap
+          command: snapcraft --use-lxd
+      - run:
+          name: publish snap
+          command: snapcraft push *.snap --release << parameters.channel >>
+
+
  build-and-push-image:
    description: build and push docker images to public AWS ECR registry
    executor: aws-cli/default
@ -907,3 +935,26 @@ workflows:
            tags:
              only:
                - /^v\d+\.\d+\.\d+(-rc\d+)?$/
+      - publish-snapcraft:
+          name: publish-snapcraft-stable
+          channel: stable
+          filters:
+            branches:
+              ignore:
+                - /.*/
+            tags:
+              only:
+                - /^v\d+\.\d+\.\d+(-rc\d+)?$/
+
+  nightly:
+    triggers:
+      - schedule:
+          cron: "0 0 * * *"
+          filters:
+            branches:
+              only:
+                - master
+    jobs:
+      - publish-snapcraft:
+          name: publish-snapcraft-nightly
+          channel: edge
--- a/api/api_worker.go
+++ b/api/api_worker.go
@ -2,7 +2,6 @@ package api

 import (
 	"context"
-	"io"

 	"github.com/google/uuid"
 	"github.com/ipfs/go-cid"
@ -43,7 +42,6 @@ type Worker interface {
 	ReleaseUnsealed(ctx context.Context, sector storage.SectorRef, safeToFree []storage.Range) (storiface.CallID, error)                                                                                 //perm:admin
 	MoveStorage(ctx context.Context, sector storage.SectorRef, types storiface.SectorFileType) (storiface.CallID, error)                                                                                 //perm:admin
 	UnsealPiece(context.Context, storage.SectorRef, storiface.UnpaddedByteIndex, abi.UnpaddedPieceSize, abi.SealRandomness, cid.Cid) (storiface.CallID, error)                                           //perm:admin
-	ReadPiece(context.Context, io.Writer, storage.SectorRef, storiface.UnpaddedByteIndex, abi.UnpaddedPieceSize) (storiface.CallID, error)                                                               //perm:admin
 	Fetch(context.Context, storage.SectorRef, storiface.SectorFileType, storiface.PathType, storiface.AcquireMode) (storiface.CallID, error)                                                             //perm:admin

 	TaskDisable(ctx context.Context, tt sealtasks.TaskType) error //perm:admin
--- a/api/mocks/mock_full.go
+++ b/api/mocks/mock_full.go
--- a/api/proxy_gen.go
+++ b/api/proxy_gen.go
@ -4,7 +4,6 @@ package api

 import (
 	"context"
-	"io"
 	"time"

 	"github.com/filecoin-project/go-address"
@ -781,8 +780,6 @@ type WorkerStruct struct {

 		ProcessSession func(p0 context.Context) (uuid.UUID, error) `perm:"admin"`

-		ReadPiece func(p0 context.Context, p1 io.Writer, p2 storage.SectorRef, p3 storiface.UnpaddedByteIndex, p4 abi.UnpaddedPieceSize) (storiface.CallID, error) `perm:"admin"`
-
 		ReleaseUnsealed func(p0 context.Context, p1 storage.SectorRef, p2 []storage.Range) (storiface.CallID, error) `perm:"admin"`

 		Remove func(p0 context.Context, p1 abi.SectorID) error `perm:"admin"`
@ -3554,14 +3551,6 @@ func (s *WorkerStub) ProcessSession(p0 context.Context) (uuid.UUID, error) {
 	return *new(uuid.UUID), xerrors.New("method not supported")
 }

-func (s *WorkerStruct) ReadPiece(p0 context.Context, p1 io.Writer, p2 storage.SectorRef, p3 storiface.UnpaddedByteIndex, p4 abi.UnpaddedPieceSize) (storiface.CallID, error) {
-	return s.Internal.ReadPiece(p0, p1, p2, p3, p4)
-}
-
-func (s *WorkerStub) ReadPiece(p0 context.Context, p1 io.Writer, p2 storage.SectorRef, p3 storiface.UnpaddedByteIndex, p4 abi.UnpaddedPieceSize) (storiface.CallID, error) {
-	return *new(storiface.CallID), xerrors.New("method not supported")
-}
-
 func (s *WorkerStruct) ReleaseUnsealed(p0 context.Context, p1 storage.SectorRef, p2 []storage.Range) (storiface.CallID, error) {
 	return s.Internal.ReleaseUnsealed(p0, p1, p2)
 }
--- a/api/test/mining.go
+++ b/api/test/mining.go
@ -1,240 +0,0 @@
-package test
-
-import (
-	"bytes"
-	"context"
-	"fmt"
-	"math/rand"
-	"sync/atomic"
-	"testing"
-	"time"
-
-	logging "github.com/ipfs/go-log/v2"
-
-	"github.com/stretchr/testify/require"
-
-	"github.com/filecoin-project/go-address"
-	"github.com/filecoin-project/go-state-types/abi"
-
-	"github.com/filecoin-project/lotus/build"
-	"github.com/filecoin-project/lotus/chain/types"
-	"github.com/filecoin-project/lotus/miner"
-	"github.com/filecoin-project/lotus/node/impl"
-)
-
-//nolint:deadcode,varcheck
-var log = logging.Logger("apitest")
-
-func (ts *testSuite) testMining(t *testing.T) {
-	ctx := context.Background()
-	apis, sn := ts.makeNodes(t, OneFull, OneMiner)
-	api := apis[0]
-
-	newHeads, err := api.ChainNotify(ctx)
-	require.NoError(t, err)
-	initHead := (<-newHeads)[0]
-	baseHeight := initHead.Val.Height()
-
-	h1, err := api.ChainHead(ctx)
-	require.NoError(t, err)
-	require.Equal(t, int64(h1.Height()), int64(baseHeight))
-
-	MineUntilBlock(ctx, t, apis[0], sn[0], nil)
-	require.NoError(t, err)
-
-	<-newHeads
-
-	h2, err := api.ChainHead(ctx)
-	require.NoError(t, err)
-	require.Greater(t, int64(h2.Height()), int64(h1.Height()))
-}
-
-func (ts *testSuite) testMiningReal(t *testing.T) {
-	build.InsecurePoStValidation = false
-	defer func() {
-		build.InsecurePoStValidation = true
-	}()
-
-	ctx := context.Background()
-	apis, sn := ts.makeNodes(t, OneFull, OneMiner)
-	api := apis[0]
-
-	newHeads, err := api.ChainNotify(ctx)
-	require.NoError(t, err)
-	at := (<-newHeads)[0].Val.Height()
-
-	h1, err := api.ChainHead(ctx)
-	require.NoError(t, err)
-	require.Equal(t, int64(at), int64(h1.Height()))
-
-	MineUntilBlock(ctx, t, apis[0], sn[0], nil)
-	require.NoError(t, err)
-
-	<-newHeads
-
-	h2, err := api.ChainHead(ctx)
-	require.NoError(t, err)
-	require.Greater(t, int64(h2.Height()), int64(h1.Height()))
-
-	MineUntilBlock(ctx, t, apis[0], sn[0], nil)
-	require.NoError(t, err)
-
-	<-newHeads
-
-	h3, err := api.ChainHead(ctx)
-	require.NoError(t, err)
-	require.Greater(t, int64(h3.Height()), int64(h2.Height()))
-}
-
-func TestDealMining(t *testing.T, b APIBuilder, blocktime time.Duration, carExport bool) {
-	// test making a deal with a fresh miner, and see if it starts to mine
-
-	ctx := context.Background()
-	n, sn := b(t, OneFull, []StorageMiner{
-		{Full: 0, Preseal: PresealGenesis},
-		{Full: 0, Preseal: 0}, // TODO: Add support for miners on non-first full node
-	})
-	client := n[0].FullNode.(*impl.FullNodeAPI)
-	provider := sn[1]
-	genesisMiner := sn[0]
-
-	addrinfo, err := client.NetAddrsListen(ctx)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if err := provider.NetConnect(ctx, addrinfo); err != nil {
-		t.Fatal(err)
-	}
-
-	if err := genesisMiner.NetConnect(ctx, addrinfo); err != nil {
-		t.Fatal(err)
-	}
-
-	time.Sleep(time.Second)
-
-	data := make([]byte, 600)
-	rand.New(rand.NewSource(5)).Read(data)
-
-	r := bytes.NewReader(data)
-	fcid, err := client.ClientImportLocal(ctx, r)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	fmt.Println("FILE CID: ", fcid)
-
-	var mine int32 = 1
-	done := make(chan struct{})
-	minedTwo := make(chan struct{})
-
-	m2addr, err := sn[1].ActorAddress(context.TODO())
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	go func() {
-		defer close(done)
-
-		complChan := minedTwo
-		for atomic.LoadInt32(&mine) != 0 {
-			wait := make(chan int)
-			mdone := func(mined bool, _ abi.ChainEpoch, err error) {
-				n := 0
-				if mined {
-					n = 1
-				}
-				wait <- n
-			}
-
-			if err := sn[0].MineOne(ctx, miner.MineReq{Done: mdone}); err != nil {
-				t.Error(err)
-			}
-
-			if err := sn[1].MineOne(ctx, miner.MineReq{Done: mdone}); err != nil {
-				t.Error(err)
-			}
-
-			expect := <-wait
-			expect += <-wait
-
-			time.Sleep(blocktime)
-			if expect == 0 {
-				// null block
-				continue
-			}
-
-			var nodeOneMined bool
-			for _, node := range sn {
-				mb, err := node.MiningBase(ctx)
-				if err != nil {
-					t.Error(err)
-					return
-				}
-
-				for _, b := range mb.Blocks() {
-					if b.Miner == m2addr {
-						nodeOneMined = true
-						break
-					}
-				}
-
-			}
-
-			if nodeOneMined && complChan != nil {
-				close(complChan)
-				complChan = nil
-			}
-
-		}
-	}()
-
-	deal := startDeal(t, ctx, provider, client, fcid, false, 0)
-
-	// TODO: this sleep is only necessary because deals don't immediately get logged in the dealstore, we should fix this
-	time.Sleep(time.Second)
-
-	waitDealSealed(t, ctx, provider, client, deal, false, false, nil)
-
-	<-minedTwo
-
-	atomic.StoreInt32(&mine, 0)
-	fmt.Println("shutting down mining")
-	<-done
-}
-
-func (ts *testSuite) testNonGenesisMiner(t *testing.T) {
-	ctx := context.Background()
-	n, sn := ts.makeNodes(t, []FullNodeOpts{
-		FullNodeWithLatestActorsAt(-1),
-	}, []StorageMiner{
-		{Full: 0, Preseal: PresealGenesis},
-	})
-
-	full, ok := n[0].FullNode.(*impl.FullNodeAPI)
-	if !ok {
-		t.Skip("not testing with a full node")
-		return
-	}
-	genesisMiner := sn[0]
-
-	bm := NewBlockMiner(ctx, t, genesisMiner, 4*time.Millisecond)
-	bm.MineBlocks()
-	t.Cleanup(bm.Stop)
-
-	gaa, err := genesisMiner.ActorAddress(ctx)
-	require.NoError(t, err)
-
-	gmi, err := full.StateMinerInfo(ctx, gaa, types.EmptyTSK)
-	require.NoError(t, err)
-
-	testm := n[0].Stb(ctx, t, TestSpt, gmi.Owner)
-
-	ta, err := testm.ActorAddress(ctx)
-	require.NoError(t, err)
-
-	tid, err := address.IDFromAddress(ta)
-	require.NoError(t, err)
-
-	require.Equal(t, uint64(1001), tid)
-}
--- a/api/v0api/v0mocks/mock_full.go
+++ b/api/v0api/v0mocks/mock_full.go
--- a/api/version.go
+++ b/api/version.go
@ -57,8 +57,8 @@ var (
 	FullAPIVersion0 = newVer(1, 3, 0)
 	FullAPIVersion1 = newVer(2, 1, 0)

-	MinerAPIVersion0  = newVer(1, 0, 1)
-	WorkerAPIVersion0 = newVer(1, 0, 0)
+	MinerAPIVersion0  = newVer(1, 1, 0)
+	WorkerAPIVersion0 = newVer(1, 1, 0)
 )

 //nolint:varcheck,deadcode
--- a/build/openrpc/full.json.gz
+++ b/build/openrpc/full.json.gz
--- a/build/openrpc/miner.json.gz
+++ b/build/openrpc/miner.json.gz
--- a/build/openrpc/worker.json.gz
+++ b/build/openrpc/worker.json.gz
--- a/cli/servicesmock_test.go
+++ b/cli/servicesmock_test.go
@ -6,39 +6,40 @@ package cli

 import (
 	context "context"
+	reflect "reflect"
+
 	go_address "github.com/filecoin-project/go-address"
 	abi "github.com/filecoin-project/go-state-types/abi"
 	big "github.com/filecoin-project/go-state-types/big"
 	api "github.com/filecoin-project/lotus/api"
 	types "github.com/filecoin-project/lotus/chain/types"
 	gomock "github.com/golang/mock/gomock"
-	reflect "reflect"
 )

-// MockServicesAPI is a mock of ServicesAPI interface
+// MockServicesAPI is a mock of ServicesAPI interface.
 type MockServicesAPI struct {
 	ctrl     *gomock.Controller
 	recorder *MockServicesAPIMockRecorder
 }

-// MockServicesAPIMockRecorder is the mock recorder for MockServicesAPI
+// MockServicesAPIMockRecorder is the mock recorder for MockServicesAPI.
 type MockServicesAPIMockRecorder struct {
 	mock *MockServicesAPI
 }

-// NewMockServicesAPI creates a new mock instance
+// NewMockServicesAPI creates a new mock instance.
 func NewMockServicesAPI(ctrl *gomock.Controller) *MockServicesAPI {
 	mock := &MockServicesAPI{ctrl: ctrl}
 	mock.recorder = &MockServicesAPIMockRecorder{mock}
 	return mock
 }

-// EXPECT returns an object that allows the caller to indicate expected use
+// EXPECT returns an object that allows the caller to indicate expected use.
 func (m *MockServicesAPI) EXPECT() *MockServicesAPIMockRecorder {
 	return m.recorder
 }

-// Close mocks base method
+// Close mocks base method.
 func (m *MockServicesAPI) Close() error {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "Close")
@ -46,13 +47,13 @@ func (m *MockServicesAPI) Close() error {
 	return ret0
 }

-// Close indicates an expected call of Close
+// Close indicates an expected call of Close.
 func (mr *MockServicesAPIMockRecorder) Close() *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Close", reflect.TypeOf((*MockServicesAPI)(nil).Close))
 }

-// DecodeTypedParamsFromJSON mocks base method
+// DecodeTypedParamsFromJSON mocks base method.
 func (m *MockServicesAPI) DecodeTypedParamsFromJSON(arg0 context.Context, arg1 go_address.Address, arg2 abi.MethodNum, arg3 string) ([]byte, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "DecodeTypedParamsFromJSON", arg0, arg1, arg2, arg3)
@ -61,13 +62,13 @@ func (m *MockServicesAPI) DecodeTypedParamsFromJSON(arg0 context.Context, arg1 g
 	return ret0, ret1
 }

-// DecodeTypedParamsFromJSON indicates an expected call of DecodeTypedParamsFromJSON
+// DecodeTypedParamsFromJSON indicates an expected call of DecodeTypedParamsFromJSON.
 func (mr *MockServicesAPIMockRecorder) DecodeTypedParamsFromJSON(arg0, arg1, arg2, arg3 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "DecodeTypedParamsFromJSON", reflect.TypeOf((*MockServicesAPI)(nil).DecodeTypedParamsFromJSON), arg0, arg1, arg2, arg3)
 }

-// FullNodeAPI mocks base method
+// FullNodeAPI mocks base method.
 func (m *MockServicesAPI) FullNodeAPI() api.FullNode {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "FullNodeAPI")
@ -75,13 +76,13 @@ func (m *MockServicesAPI) FullNodeAPI() api.FullNode {
 	return ret0
 }

-// FullNodeAPI indicates an expected call of FullNodeAPI
+// FullNodeAPI indicates an expected call of FullNodeAPI.
 func (mr *MockServicesAPIMockRecorder) FullNodeAPI() *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "FullNodeAPI", reflect.TypeOf((*MockServicesAPI)(nil).FullNodeAPI))
 }

-// GetBaseFee mocks base method
+// GetBaseFee mocks base method.
 func (m *MockServicesAPI) GetBaseFee(arg0 context.Context) (big.Int, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "GetBaseFee", arg0)
@ -90,13 +91,13 @@ func (m *MockServicesAPI) GetBaseFee(arg0 context.Context) (big.Int, error) {
 	return ret0, ret1
 }

-// GetBaseFee indicates an expected call of GetBaseFee
+// GetBaseFee indicates an expected call of GetBaseFee.
 func (mr *MockServicesAPIMockRecorder) GetBaseFee(arg0 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetBaseFee", reflect.TypeOf((*MockServicesAPI)(nil).GetBaseFee), arg0)
 }

-// LocalAddresses mocks base method
+// LocalAddresses mocks base method.
 func (m *MockServicesAPI) LocalAddresses(arg0 context.Context) (go_address.Address, []go_address.Address, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "LocalAddresses", arg0)
@ -106,13 +107,13 @@ func (m *MockServicesAPI) LocalAddresses(arg0 context.Context) (go_address.Addre
 	return ret0, ret1, ret2
 }

-// LocalAddresses indicates an expected call of LocalAddresses
+// LocalAddresses indicates an expected call of LocalAddresses.
 func (mr *MockServicesAPIMockRecorder) LocalAddresses(arg0 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "LocalAddresses", reflect.TypeOf((*MockServicesAPI)(nil).LocalAddresses), arg0)
 }

-// MessageForSend mocks base method
+// MessageForSend mocks base method.
 func (m *MockServicesAPI) MessageForSend(arg0 context.Context, arg1 SendParams) (*api.MessagePrototype, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "MessageForSend", arg0, arg1)
@ -121,13 +122,13 @@ func (m *MockServicesAPI) MessageForSend(arg0 context.Context, arg1 SendParams)
 	return ret0, ret1
 }

-// MessageForSend indicates an expected call of MessageForSend
+// MessageForSend indicates an expected call of MessageForSend.
 func (mr *MockServicesAPIMockRecorder) MessageForSend(arg0, arg1 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "MessageForSend", reflect.TypeOf((*MockServicesAPI)(nil).MessageForSend), arg0, arg1)
 }

-// MpoolCheckPendingMessages mocks base method
+// MpoolCheckPendingMessages mocks base method.
 func (m *MockServicesAPI) MpoolCheckPendingMessages(arg0 context.Context, arg1 go_address.Address) ([][]api.MessageCheckStatus, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "MpoolCheckPendingMessages", arg0, arg1)
@ -136,13 +137,13 @@ func (m *MockServicesAPI) MpoolCheckPendingMessages(arg0 context.Context, arg1 g
 	return ret0, ret1
 }

-// MpoolCheckPendingMessages indicates an expected call of MpoolCheckPendingMessages
+// MpoolCheckPendingMessages indicates an expected call of MpoolCheckPendingMessages.
 func (mr *MockServicesAPIMockRecorder) MpoolCheckPendingMessages(arg0, arg1 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "MpoolCheckPendingMessages", reflect.TypeOf((*MockServicesAPI)(nil).MpoolCheckPendingMessages), arg0, arg1)
 }

-// MpoolPendingFilter mocks base method
+// MpoolPendingFilter mocks base method.
 func (m *MockServicesAPI) MpoolPendingFilter(arg0 context.Context, arg1 func(*types.SignedMessage) bool, arg2 types.TipSetKey) ([]*types.SignedMessage, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "MpoolPendingFilter", arg0, arg1, arg2)
@ -151,13 +152,13 @@ func (m *MockServicesAPI) MpoolPendingFilter(arg0 context.Context, arg1 func(*ty
 	return ret0, ret1
 }

-// MpoolPendingFilter indicates an expected call of MpoolPendingFilter
+// MpoolPendingFilter indicates an expected call of MpoolPendingFilter.
 func (mr *MockServicesAPIMockRecorder) MpoolPendingFilter(arg0, arg1, arg2 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "MpoolPendingFilter", reflect.TypeOf((*MockServicesAPI)(nil).MpoolPendingFilter), arg0, arg1, arg2)
 }

-// PublishMessage mocks base method
+// PublishMessage mocks base method.
 func (m *MockServicesAPI) PublishMessage(arg0 context.Context, arg1 *api.MessagePrototype, arg2 bool) (*types.SignedMessage, [][]api.MessageCheckStatus, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "PublishMessage", arg0, arg1, arg2)
@ -167,13 +168,13 @@ func (m *MockServicesAPI) PublishMessage(arg0 context.Context, arg1 *api.Message
 	return ret0, ret1, ret2
 }

-// PublishMessage indicates an expected call of PublishMessage
+// PublishMessage indicates an expected call of PublishMessage.
 func (mr *MockServicesAPIMockRecorder) PublishMessage(arg0, arg1, arg2 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "PublishMessage", reflect.TypeOf((*MockServicesAPI)(nil).PublishMessage), arg0, arg1, arg2)
 }

-// RunChecksForPrototype mocks base method
+// RunChecksForPrototype mocks base method.
 func (m *MockServicesAPI) RunChecksForPrototype(arg0 context.Context, arg1 *api.MessagePrototype) ([][]api.MessageCheckStatus, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "RunChecksForPrototype", arg0, arg1)
@ -182,7 +183,7 @@ func (m *MockServicesAPI) RunChecksForPrototype(arg0 context.Context, arg1 *api.
 	return ret0, ret1
 }

-// RunChecksForPrototype indicates an expected call of RunChecksForPrototype
+// RunChecksForPrototype indicates an expected call of RunChecksForPrototype.
 func (mr *MockServicesAPIMockRecorder) RunChecksForPrototype(arg0, arg1 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "RunChecksForPrototype", reflect.TypeOf((*MockServicesAPI)(nil).RunChecksForPrototype), arg0, arg1)
--- a/cmd/lotus-seal-worker/main.go
+++ b/cmd/lotus-seal-worker/main.go
@ -362,9 +362,10 @@ var runCmd = &cli.Command{
 			return xerrors.Errorf("could not get api info: %w", err)
 		}

-		remote := stores.NewRemote(localStore, nodeApi, sminfo.AuthHeader(), cctx.Int("parallel-fetch-limit"))
+		remote := stores.NewRemote(localStore, nodeApi, sminfo.AuthHeader(), cctx.Int("parallel-fetch-limit"),
+			&stores.DefaultPartialFileHandler{})

-		fh := &stores.FetchHandler{Local: localStore}
+		fh := &stores.FetchHandler{Local: localStore, PfHandler: &stores.DefaultPartialFileHandler{}}
 		remoteHandler := func(w http.ResponseWriter, r *http.Request) {
 			if !auth.HasPerm(r.Context(), nil, api.PermAdmin) {
 				w.WriteHeader(401)
--- a/cmd/lotus-storage-miner/init.go
+++ b/cmd/lotus-storage-miner/init.go
@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"net/http"
 	"os"
 	"path/filepath"
 	"strconv"
@ -453,14 +454,23 @@ func storageMinerInit(ctx context.Context, cctx *cli.Context, api v1api.FullNode
 			wsts := statestore.New(namespace.Wrap(mds, modules.WorkerCallsPrefix))
 			smsts := statestore.New(namespace.Wrap(mds, modules.ManagerWorkPrefix))

-			smgr, err := sectorstorage.New(ctx, lr, stores.NewIndex(), sectorstorage.SealerConfig{
+			si := stores.NewIndex()
+
+			lstor, err := stores.NewLocal(ctx, lr, si, nil)
+			if err != nil {
+				return err
+			}
+			stor := stores.NewRemote(lstor, si, http.Header(sa), 10, &stores.DefaultPartialFileHandler{})
+
+			smgr, err := sectorstorage.New(ctx, lstor, stor, lr, si, sectorstorage.SealerConfig{
 				ParallelFetchLimit: 10,
 				AllowAddPiece:      true,
 				AllowPreCommit1:    true,
 				AllowPreCommit2:    true,
 				AllowCommit:        true,
 				AllowUnseal:        true,
-			}, nil, sa, wsts, smsts)
+			}, wsts, smsts)
+
 			if err != nil {
 				return err
 			}
--- a/documentation/en/api-v0-methods-worker.md
+++ b/documentation/en/api-v0-methods-worker.md
@ -15,8 +15,6 @@
  * [MoveStorage](#MoveStorage)
 * [Process](#Process)
  * [ProcessSession](#ProcessSession)
-* [Read](#Read)
-  * [ReadPiece](#ReadPiece)
 * [Release](#Release)
  * [ReleaseUnsealed](#ReleaseUnsealed)
 * [Seal](#Seal)
@ -263,41 +261,6 @@ Inputs: `null`

 Response: `"07070707-0707-0707-0707-070707070707"`

-## Read
-
-
-### ReadPiece
-
-
-Perms: admin
-
-Inputs:
-```json
-[
-  {},
-  {
-    "ID": {
-      "Miner": 1000,
-      "Number": 9
-    },
-    "ProofType": 8
-  },
-  1040384,
-  1024
-]
-```
-
-Response:
-```json
-{
-  "Sector": {
-    "Miner": 1000,
-    "Number": 9
-  },
-  "ID": "07070707-0707-0707-0707-070707070707"
-}
-```
-
 ## Release


--- a/extern/sector-storage/ffiwrapper/sealer_cgo.go
+++ b/extern/sector-storage/ffiwrapper/sealer_cgo.go
@ -11,6 +11,7 @@ import (
 	"os"
 	"runtime"

+	"github.com/filecoin-project/lotus/extern/sector-storage/partialfile"
 	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"

@ -66,7 +67,7 @@ func (sb *Sealer) AddPiece(ctx context.Context, sector storage.SectorRef, existi
 	}

 	var done func()
-	var stagedFile *partialFile
+	var stagedFile *partialfile.PartialFile

 	defer func() {
 		if done != nil {
@ -87,7 +88,7 @@ func (sb *Sealer) AddPiece(ctx context.Context, sector storage.SectorRef, existi
 			return abi.PieceInfo{}, xerrors.Errorf("acquire unsealed sector: %w", err)
 		}

-		stagedFile, err = createPartialFile(maxPieceSize, stagedPath.Unsealed)
+		stagedFile, err = partialfile.CreatePartialFile(maxPieceSize, stagedPath.Unsealed)
 		if err != nil {
 			return abi.PieceInfo{}, xerrors.Errorf("creating unsealed sector file: %w", err)
 		}
@ -97,7 +98,7 @@ func (sb *Sealer) AddPiece(ctx context.Context, sector storage.SectorRef, existi
 			return abi.PieceInfo{}, xerrors.Errorf("acquire unsealed sector: %w", err)
 		}

-		stagedFile, err = openPartialFile(maxPieceSize, stagedPath.Unsealed)
+		stagedFile, err = partialfile.OpenPartialFile(maxPieceSize, stagedPath.Unsealed)
 		if err != nil {
 			return abi.PieceInfo{}, xerrors.Errorf("opening unsealed sector file: %w", err)
 		}
@ -257,7 +258,7 @@ func (sb *Sealer) UnsealPiece(ctx context.Context, sector storage.SectorRef, off

 	// try finding existing
 	unsealedPath, done, err := sb.sectors.AcquireSector(ctx, sector, storiface.FTUnsealed, storiface.FTNone, storiface.PathStorage)
-	var pf *partialFile
+	var pf *partialfile.PartialFile

 	switch {
 	case xerrors.Is(err, storiface.ErrSectorNotFound):
@ -267,7 +268,7 @@ func (sb *Sealer) UnsealPiece(ctx context.Context, sector storage.SectorRef, off
 		}
 		defer done()

-		pf, err = createPartialFile(maxPieceSize, unsealedPath.Unsealed)
+		pf, err = partialfile.CreatePartialFile(maxPieceSize, unsealedPath.Unsealed)
 		if err != nil {
 			return xerrors.Errorf("create unsealed file: %w", err)
 		}
@ -275,7 +276,7 @@ func (sb *Sealer) UnsealPiece(ctx context.Context, sector storage.SectorRef, off
 	case err == nil:
 		defer done()

-		pf, err = openPartialFile(maxPieceSize, unsealedPath.Unsealed)
+		pf, err = partialfile.OpenPartialFile(maxPieceSize, unsealedPath.Unsealed)
 		if err != nil {
 			return xerrors.Errorf("opening partial file: %w", err)
 		}
@ -427,7 +428,7 @@ func (sb *Sealer) ReadPiece(ctx context.Context, writer io.Writer, sector storag
 	}
 	maxPieceSize := abi.PaddedPieceSize(ssize)

-	pf, err := openPartialFile(maxPieceSize, path.Unsealed)
+	pf, err := partialfile.OpenPartialFile(maxPieceSize, path.Unsealed)
 	if err != nil {
 		if xerrors.Is(err, os.ErrNotExist) {
 			return false, nil
@ -589,7 +590,7 @@ func (sb *Sealer) FinalizeSector(ctx context.Context, sector storage.SectorRef,

 	if len(keepUnsealed) > 0 {

-		sr := pieceRun(0, maxPieceSize)
+		sr := partialfile.PieceRun(0, maxPieceSize)

 		for _, s := range keepUnsealed {
 			si := &rlepluslazy.RunSliceIterator{}
@ -611,7 +612,7 @@ func (sb *Sealer) FinalizeSector(ctx context.Context, sector storage.SectorRef,
 		}
 		defer done()

-		pf, err := openPartialFile(maxPieceSize, paths.Unsealed)
+		pf, err := partialfile.OpenPartialFile(maxPieceSize, paths.Unsealed)
 		if err == nil {
 			var at uint64
 			for sr.HasNext() {
--- a/extern/sector-storage/ffiwrapper/unseal_ranges.go
+++ b/extern/sector-storage/ffiwrapper/unseal_ranges.go
@ -1,6 +1,7 @@
 package ffiwrapper

 import (
+	"github.com/filecoin-project/lotus/extern/sector-storage/partialfile"
 	"golang.org/x/xerrors"

 	rlepluslazy "github.com/filecoin-project/go-bitfield/rle"
@ -17,7 +18,7 @@ const mergeGaps = 32 << 20
 // TODO const expandRuns = 16 << 20 // unseal more than requested for future requests

 func computeUnsealRanges(unsealed rlepluslazy.RunIterator, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (rlepluslazy.RunIterator, error) {
-	todo := pieceRun(offset.Padded(), size.Padded())
+	todo := partialfile.PieceRun(offset.Padded(), size.Padded())
 	todo, err := rlepluslazy.Subtract(todo, unsealed)
 	if err != nil {
 		return nil, xerrors.Errorf("compute todo-unsealed: %w", err)
--- a/extern/sector-storage/fr32/readers.go
+++ b/extern/sector-storage/fr32/readers.go
@ -51,13 +51,12 @@ func (r *unpadReader) Read(out []byte) (int, error) {

 	r.left -= uint64(todo)

-	n, err := r.src.Read(r.work[:todo])
+	n, err := io.ReadAtLeast(r.src, r.work[:todo], int(todo))
 	if err != nil && err != io.EOF {
 		return n, err
 	}
-
-	if n != int(todo) {
-		return 0, xerrors.Errorf("didn't read enough: %w", err)
+	if n < int(todo) {
+		return 0, xerrors.Errorf("didn't read enough: %d / %d, left %d, out %d", n, todo, r.left, len(out))
 	}

 	Unpad(r.work[:todo], out[:todo.Unpadded()])
--- a/extern/sector-storage/manager.go
+++ b/extern/sector-storage/manager.go
@ -47,8 +47,6 @@ type Worker interface {
 }

 type SectorManager interface {
-	ReadPiece(context.Context, io.Writer, storage.SectorRef, storiface.UnpaddedByteIndex, abi.UnpaddedPieceSize, abi.SealRandomness, cid.Cid) error
-
 	ffiwrapper.StorageSealer
 	storage.Prover
 	storiface.WorkerReturn
@ -105,24 +103,18 @@ type StorageAuth http.Header
 type WorkerStateStore *statestore.StateStore
 type ManagerStateStore *statestore.StateStore

-func New(ctx context.Context, ls stores.LocalStorage, si stores.SectorIndex, sc SealerConfig, urls URLs, sa StorageAuth, wss WorkerStateStore, mss ManagerStateStore) (*Manager, error) {
-	lstor, err := stores.NewLocal(ctx, ls, si, urls)
-	if err != nil {
-		return nil, err
-	}
+func New(ctx context.Context, lstor *stores.Local, stor *stores.Remote, ls stores.LocalStorage, si stores.SectorIndex, sc SealerConfig, wss WorkerStateStore, mss ManagerStateStore) (*Manager, error) {

 	prover, err := ffiwrapper.New(&readonlyProvider{stor: lstor, index: si})
 	if err != nil {
 		return nil, xerrors.Errorf("creating prover instance: %w", err)
 	}

-	stor := stores.NewRemote(lstor, si, http.Header(sa), sc.ParallelFetchLimit)
-
 	m := &Manager{
 		ls:         ls,
 		storage:    stor,
 		localStore: lstor,
-		remoteHnd:  &stores.FetchHandler{Local: lstor},
+		remoteHnd:  &stores.FetchHandler{Local: lstor, PfHandler: &stores.DefaultPartialFileHandler{}},
 		index:      si,

 		sched: newScheduler(),
@ -141,7 +133,7 @@ func New(ctx context.Context, ls stores.LocalStorage, si stores.SectorIndex, sc
 	go m.sched.runSched()

 	localTasks := []sealtasks.TaskType{
-		sealtasks.TTCommit1, sealtasks.TTFinalize, sealtasks.TTFetch, sealtasks.TTReadUnsealed,
+		sealtasks.TTCommit1, sealtasks.TTFinalize, sealtasks.TTFetch,
 	}
 	if sc.AllowAddPiece {
 		localTasks = append(localTasks, sealtasks.TTAddPiece)
@ -206,71 +198,11 @@ func (m *Manager) schedFetch(sector storage.SectorRef, ft storiface.SectorFileTy
 	}
 }

-func (m *Manager) readPiece(sink io.Writer, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, rok *bool) func(ctx context.Context, w Worker) error {
-	return func(ctx context.Context, w Worker) error {
-		log.Debugf("read piece data from sector %d, offset %d, size %d", sector.ID, offset, size)
-		r, err := m.waitSimpleCall(ctx)(w.ReadPiece(ctx, sink, sector, offset, size))
-		if err != nil {
-			return err
-		}
-		if r != nil {
-			*rok = r.(bool)
-		}
-		log.Debugf("completed read piece data from sector %d, offset %d, size %d: read ok? %t", sector.ID, offset, size, *rok)
-		return nil
-	}
-}
-
-func (m *Manager) tryReadUnsealedPiece(ctx context.Context, sink io.Writer, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (foundUnsealed bool, readOk bool, selector WorkerSelector, returnErr error) {
-
-	// acquire a lock purely for reading unsealed sectors
-	ctx, cancel := context.WithCancel(ctx)
-	defer cancel()
-
-	log.Debugf("acquire read sector lock for sector %d", sector.ID)
-	if err := m.index.StorageLock(ctx, sector.ID, storiface.FTUnsealed, storiface.FTNone); err != nil {
-		returnErr = xerrors.Errorf("acquiring read sector lock: %w", err)
-		return
-	}
-
-	log.Debugf("find unsealed sector %d", sector.ID)
-	// passing 0 spt because we only need it when allowFetch is true
-	best, err := m.index.StorageFindSector(ctx, sector.ID, storiface.FTUnsealed, 0, false)
-	if err != nil {
-		returnErr = xerrors.Errorf("read piece: checking for already existing unsealed sector: %w", err)
-		return
-	}
-
-	foundUnsealed = len(best) > 0
-	if foundUnsealed { // append to existing
-		// There is unsealed sector, see if we can read from it
-		log.Debugf("found unsealed sector %d", sector.ID)
-
-		selector = newExistingSelector(m.index, sector.ID, storiface.FTUnsealed, false)
-
-		log.Debugf("scheduling read of unsealed sector %d", sector.ID)
-		err = m.sched.Schedule(ctx, sector, sealtasks.TTReadUnsealed, selector, m.schedFetch(sector, storiface.FTUnsealed, storiface.PathSealing, storiface.AcquireMove),
-			m.readPiece(sink, sector, offset, size, &readOk))
-		if err != nil {
-			returnErr = xerrors.Errorf("reading piece from sealed sector: %w", err)
-		}
-	} else {
-		log.Debugf("did not find unsealed sector %d", sector.ID)
-		selector = newAllocSelector(m.index, storiface.FTUnsealed, storiface.PathSealing)
-	}
-	return
-}
-
-func (m *Manager) ReadPiece(ctx context.Context, sink io.Writer, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, ticket abi.SealRandomness, unsealed cid.Cid) error {
-	log.Debugf("fetch and read piece in sector %d, offset %d, size %d", sector.ID, offset, size)
-	foundUnsealed, readOk, selector, err := m.tryReadUnsealedPiece(ctx, sink, sector, offset, size)
-	if err != nil {
-		return err
-	}
-	if readOk {
-		log.Debugf("completed read of unsealed piece in sector %d, offset %d, size %d", sector.ID, offset, size)
-		return nil
-	}
+// SectorsUnsealPiece will Unseal the Sealed sector file for the given sector.
+// It will schedule the Unsealing task on a worker that either already has the sealed sector files or has space in
+// one of it's sealing scratch spaces to store them after fetching them from another worker.
+// If the chosen worker already has the Unsealed sector file, we will NOT Unseal the sealed sector file again.
+func (m *Manager) SectorsUnsealPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, ticket abi.SealRandomness, unsealed *cid.Cid) error {
 	ctx, cancel := context.WithCancel(ctx)
 	defer cancel()

@ -279,22 +211,18 @@ func (m *Manager) ReadPiece(ctx context.Context, sink io.Writer, sector storage.
 		return xerrors.Errorf("acquiring unseal sector lock: %w", err)
 	}

-	unsealFetch := func(ctx context.Context, worker Worker) error {
+	// if the selected worker does NOT have the sealed files for the sector, instruct it to fetch it from a worker that has them and
+	// put it in the sealing scratch space.
+	sealFetch := func(ctx context.Context, worker Worker) error {
 		log.Debugf("copy sealed/cache sector data for sector %d", sector.ID)
 		if _, err := m.waitSimpleCall(ctx)(worker.Fetch(ctx, sector, storiface.FTSealed|storiface.FTCache, storiface.PathSealing, storiface.AcquireCopy)); err != nil {
 			return xerrors.Errorf("copy sealed/cache sector data: %w", err)
 		}

-		if foundUnsealed {
-			log.Debugf("copy unsealed sector data for sector %d", sector.ID)
-			if _, err := m.waitSimpleCall(ctx)(worker.Fetch(ctx, sector, storiface.FTUnsealed, storiface.PathSealing, storiface.AcquireMove)); err != nil {
-				return xerrors.Errorf("copy unsealed sector data: %w", err)
-			}
-		}
 		return nil
 	}

-	if unsealed == cid.Undef {
+	if unsealed == nil {
 		return xerrors.Errorf("cannot unseal piece (sector: %d, offset: %d size: %d) - unsealed cid is undefined", sector, offset, size)
 	}

@ -303,36 +231,28 @@ func (m *Manager) ReadPiece(ctx context.Context, sink io.Writer, sector storage.
 		return xerrors.Errorf("getting sector size: %w", err)
 	}

-	log.Debugf("schedule unseal for sector %d", sector.ID)
-	err = m.sched.Schedule(ctx, sector, sealtasks.TTUnseal, selector, unsealFetch, func(ctx context.Context, w Worker) error {
+	// selector will schedule the Unseal task on a worker that either already has the sealed sector files or has space in
+	// one of it's sealing scratch spaces to store them after fetching them from another worker.
+	selector := newExistingSelector(m.index, sector.ID, storiface.FTSealed|storiface.FTCache, true)
+
+	log.Debugf("will schedule unseal for sector %d", sector.ID)
+	err = m.sched.Schedule(ctx, sector, sealtasks.TTUnseal, selector, sealFetch, func(ctx context.Context, w Worker) error {
 		// TODO: make restartable

 		// NOTE: we're unsealing the whole sector here as with SDR we can't really
 		//  unseal the sector partially. Requesting the whole sector here can
 		//  save us some work in case another piece is requested from here
-		log.Debugf("unseal sector %d", sector.ID)
-		_, err := m.waitSimpleCall(ctx)(w.UnsealPiece(ctx, sector, 0, abi.PaddedPieceSize(ssize).Unpadded(), ticket, unsealed))
+		log.Debugf("calling unseal sector on worker, sectoID=%d", sector.ID)
+
+		// Note: This unseal piece call will essentially become a no-op if the worker already has an Unsealed sector file for the given sector.
+		_, err := m.waitSimpleCall(ctx)(w.UnsealPiece(ctx, sector, 0, abi.PaddedPieceSize(ssize).Unpadded(), ticket, *unsealed))
 		log.Debugf("completed unseal sector %d", sector.ID)
 		return err
 	})
 	if err != nil {
-		return err
+		return xerrors.Errorf("worker UnsealPiece call: %s", err)
 	}

-	selector = newExistingSelector(m.index, sector.ID, storiface.FTUnsealed, false)
-
-	log.Debugf("schedule read piece for sector %d, offset %d, size %d", sector.ID, offset, size)
-	err = m.sched.Schedule(ctx, sector, sealtasks.TTReadUnsealed, selector, m.schedFetch(sector, storiface.FTUnsealed, storiface.PathSealing, storiface.AcquireMove),
-		m.readPiece(sink, sector, offset, size, &readOk))
-	if err != nil {
-		return xerrors.Errorf("reading piece from sealed sector: %w", err)
-	}
-
-	if !readOk {
-		return xerrors.Errorf("failed to read unsealed piece")
-	}
-
-	log.Debugf("completed read of piece in sector %d, offset %d, size %d", sector.ID, offset, size)
 	return nil
 }

@ -767,4 +687,5 @@ func (m *Manager) Close(ctx context.Context) error {
 	return m.sched.Close(ctx)
 }

+var _ Unsealer = &Manager{}
 var _ SectorManager = &Manager{}
--- a/extern/sector-storage/manager_test.go
+++ b/extern/sector-storage/manager_test.go
@ -98,7 +98,7 @@ func newTestMgr(ctx context.Context, t *testing.T, ds datastore.Datastore) (*Man
 	prover, err := ffiwrapper.New(&readonlyProvider{stor: lstor, index: si})
 	require.NoError(t, err)

-	stor := stores.NewRemote(lstor, si, nil, 6000)
+	stor := stores.NewRemote(lstor, si, nil, 6000, &stores.DefaultPartialFileHandler{})

 	m := &Manager{
 		ls:         st,
--- a/extern/sector-storage/mock/mock.go
+++ b/extern/sector-storage/mock/mock.go
@ -6,6 +6,7 @@ import (
 	"crypto/sha256"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"math/rand"
 	"sync"

@ -375,13 +376,12 @@ func generateFakePoSt(sectorInfo []proof5.SectorInfo, rpt func(abi.RegisteredSea
 	}
 }

-func (mgr *SectorMgr) ReadPiece(ctx context.Context, w io.Writer, sectorID storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, randomness abi.SealRandomness, c cid.Cid) error {
+func (mgr *SectorMgr) ReadPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, ticket abi.SealRandomness, unsealed cid.Cid) (io.ReadCloser, bool, error) {
 	if offset != 0 {
 		panic("implme")
 	}

-	_, err := io.CopyN(w, bytes.NewReader(mgr.pieces[mgr.sectors[sectorID.ID].pieces[0]]), int64(size))
-	return err
+	return ioutil.NopCloser(bytes.NewReader(mgr.pieces[mgr.sectors[sector.ID].pieces[0]][:size])), false, nil
 }

 func (mgr *SectorMgr) StageFakeData(mid abi.ActorID, spt abi.RegisteredSealProof) (storage.SectorRef, []abi.PieceInfo, error) {
@ -492,6 +492,10 @@ func (mgr *SectorMgr) ReturnFetch(ctx context.Context, callID storiface.CallID,
 	panic("not supported")
 }

+func (mgr *SectorMgr) SectorsUnsealPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, randomness abi.SealRandomness, commd *cid.Cid) error {
+	return nil
+}
+
 func (m mockVerifProver) VerifySeal(svi proof5.SealVerifyInfo) (bool, error) {
 	plen, err := svi.SealProof.ProofSize()
 	if err != nil {
--- a/extern/sector-storage/partialfile/partialfile.go
+++ b/extern/sector-storage/partialfile/partialfile.go
@ -1,4 +1,4 @@
-package ffiwrapper
+package partialfile

 import (
 	"encoding/binary"
@ -7,6 +7,7 @@ import (
 	"syscall"

 	"github.com/detailyang/go-fallocate"
+	logging "github.com/ipfs/go-log/v2"
 	"golang.org/x/xerrors"

 	rlepluslazy "github.com/filecoin-project/go-bitfield/rle"
@ -16,6 +17,8 @@ import (
 	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
 )

+var log = logging.Logger("partialfile")
+
 const veryLargeRle = 1 << 20

 // Sectors can be partially unsealed. We support this by appending a small
@ -25,7 +28,7 @@ const veryLargeRle = 1 << 20
 // unsealed sector files internally have this structure
 // [unpadded (raw) data][rle+][4B LE length fo the rle+ field]

-type partialFile struct {
+type PartialFile struct {
 	maxPiece abi.PaddedPieceSize

 	path      string
@ -57,7 +60,7 @@ func writeTrailer(maxPieceSize int64, w *os.File, r rlepluslazy.RunIterator) err
 	return w.Truncate(maxPieceSize + int64(rb) + 4)
 }

-func createPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialFile, error) {
+func CreatePartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*PartialFile, error) {
 	f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE, 0644) // nolint
 	if err != nil {
 		return nil, xerrors.Errorf("openning partial file '%s': %w", path, err)
@ -89,10 +92,10 @@ func createPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialF
 		return nil, xerrors.Errorf("close empty partial file: %w", err)
 	}

-	return openPartialFile(maxPieceSize, path)
+	return OpenPartialFile(maxPieceSize, path)
 }

-func openPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialFile, error) {
+func OpenPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*PartialFile, error) {
 	f, err := os.OpenFile(path, os.O_RDWR, 0644) // nolint
 	if err != nil {
 		return nil, xerrors.Errorf("openning partial file '%s': %w", path, err)
@ -165,7 +168,7 @@ func openPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialFil
 		return nil, err
 	}

-	return &partialFile{
+	return &PartialFile{
 		maxPiece:  maxPieceSize,
 		path:      path,
 		allocated: rle,
@ -173,11 +176,11 @@ func openPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialFil
 	}, nil
 }

-func (pf *partialFile) Close() error {
+func (pf *PartialFile) Close() error {
 	return pf.file.Close()
 }

-func (pf *partialFile) Writer(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (io.Writer, error) {
+func (pf *PartialFile) Writer(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (io.Writer, error) {
 	if _, err := pf.file.Seek(int64(offset), io.SeekStart); err != nil {
 		return nil, xerrors.Errorf("seek piece start: %w", err)
 	}
@ -188,7 +191,7 @@ func (pf *partialFile) Writer(offset storiface.PaddedByteIndex, size abi.PaddedP
 			return nil, err
 		}

-		and, err := rlepluslazy.And(have, pieceRun(offset, size))
+		and, err := rlepluslazy.And(have, PieceRun(offset, size))
 		if err != nil {
 			return nil, err
 		}
@ -206,13 +209,13 @@ func (pf *partialFile) Writer(offset storiface.PaddedByteIndex, size abi.PaddedP
 	return pf.file, nil
 }

-func (pf *partialFile) MarkAllocated(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) error {
+func (pf *PartialFile) MarkAllocated(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) error {
 	have, err := pf.allocated.RunIterator()
 	if err != nil {
 		return err
 	}

-	ored, err := rlepluslazy.Or(have, pieceRun(offset, size))
+	ored, err := rlepluslazy.Or(have, PieceRun(offset, size))
 	if err != nil {
 		return err
 	}
@ -224,7 +227,7 @@ func (pf *partialFile) MarkAllocated(offset storiface.PaddedByteIndex, size abi.
 	return nil
 }

-func (pf *partialFile) Free(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) error {
+func (pf *PartialFile) Free(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) error {
 	have, err := pf.allocated.RunIterator()
 	if err != nil {
 		return err
@ -234,7 +237,7 @@ func (pf *partialFile) Free(offset storiface.PaddedByteIndex, size abi.PaddedPie
 		return xerrors.Errorf("deallocating: %w", err)
 	}

-	s, err := rlepluslazy.Subtract(have, pieceRun(offset, size))
+	s, err := rlepluslazy.Subtract(have, PieceRun(offset, size))
 	if err != nil {
 		return err
 	}
@ -246,7 +249,7 @@ func (pf *partialFile) Free(offset storiface.PaddedByteIndex, size abi.PaddedPie
 	return nil
 }

-func (pf *partialFile) Reader(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (*os.File, error) {
+func (pf *PartialFile) Reader(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (*os.File, error) {
 	if _, err := pf.file.Seek(int64(offset), io.SeekStart); err != nil {
 		return nil, xerrors.Errorf("seek piece start: %w", err)
 	}
@ -257,7 +260,7 @@ func (pf *partialFile) Reader(offset storiface.PaddedByteIndex, size abi.PaddedP
 			return nil, err
 		}

-		and, err := rlepluslazy.And(have, pieceRun(offset, size))
+		and, err := rlepluslazy.And(have, PieceRun(offset, size))
 		if err != nil {
 			return nil, err
 		}
@ -275,17 +278,17 @@ func (pf *partialFile) Reader(offset storiface.PaddedByteIndex, size abi.PaddedP
 	return pf.file, nil
 }

-func (pf *partialFile) Allocated() (rlepluslazy.RunIterator, error) {
+func (pf *PartialFile) Allocated() (rlepluslazy.RunIterator, error) {
 	return pf.allocated.RunIterator()
 }

-func (pf *partialFile) HasAllocated(offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (bool, error) {
+func (pf *PartialFile) HasAllocated(offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (bool, error) {
 	have, err := pf.Allocated()
 	if err != nil {
 		return false, err
 	}

-	u, err := rlepluslazy.And(have, pieceRun(offset.Padded(), size.Padded()))
+	u, err := rlepluslazy.And(have, PieceRun(offset.Padded(), size.Padded()))
 	if err != nil {
 		return false, err
 	}
@ -298,7 +301,7 @@ func (pf *partialFile) HasAllocated(offset storiface.UnpaddedByteIndex, size abi
 	return abi.PaddedPieceSize(uc) == size.Padded(), nil
 }

-func pieceRun(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) rlepluslazy.RunIterator {
+func PieceRun(offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) rlepluslazy.RunIterator {
 	var runs []rlepluslazy.Run
 	if offset > 0 {
 		runs = append(runs, rlepluslazy.Run{
--- a/extern/sector-storage/piece_provider.go
+++ b/extern/sector-storage/piece_provider.go
@ -0,0 +1,153 @@
+package sectorstorage
+
+import (
+	"bufio"
+	"context"
+	"io"
+
+	"github.com/ipfs/go-cid"
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/specs-storage/storage"
+
+	"github.com/filecoin-project/lotus/extern/sector-storage/fr32"
+	"github.com/filecoin-project/lotus/extern/sector-storage/stores"
+	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
+)
+
+type Unsealer interface {
+	// SectorsUnsealPiece will Unseal a Sealed sector file for the given sector.
+	SectorsUnsealPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, randomness abi.SealRandomness, commd *cid.Cid) error
+}
+
+type PieceProvider interface {
+	// ReadPiece is used to read an Unsealed piece at the given offset and of the given size from a Sector
+	ReadPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, ticket abi.SealRandomness, unsealed cid.Cid) (io.ReadCloser, bool, error)
+}
+
+type pieceProvider struct {
+	storage *stores.Remote
+	index   stores.SectorIndex
+	uns     Unsealer
+}
+
+func NewPieceProvider(storage *stores.Remote, index stores.SectorIndex, uns Unsealer) PieceProvider {
+	return &pieceProvider{
+		storage: storage,
+		index:   index,
+		uns:     uns,
+	}
+}
+
+// tryReadUnsealedPiece will try to read the unsealed piece from an existing unsealed sector file for the given sector from any worker that has it.
+// It will NOT try to schedule an Unseal of a sealed sector file for the read.
+//
+// Returns a nil reader if the piece does NOT exist in any unsealed file or there is no unsealed file for the given sector on any of the workers.
+func (p *pieceProvider) tryReadUnsealedPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (io.ReadCloser, context.CancelFunc, error) {
+	// acquire a lock purely for reading unsealed sectors
+	ctx, cancel := context.WithCancel(ctx)
+	if err := p.index.StorageLock(ctx, sector.ID, storiface.FTUnsealed, storiface.FTNone); err != nil {
+		cancel()
+		return nil, nil, xerrors.Errorf("acquiring read sector lock: %w", err)
+	}
+
+	// Reader returns a reader for an unsealed piece at the given offset in the given sector.
+	// The returned reader will be nil if none of the workers has an unsealed sector file containing
+	// the unsealed piece.
+	r, err := p.storage.Reader(ctx, sector, abi.PaddedPieceSize(offset.Padded()), size.Padded())
+	if err != nil {
+		log.Debugf("did not get storage reader;sector=%+v, err:%s", sector.ID, err)
+		cancel()
+		return nil, nil, err
+	}
+	if r == nil {
+		cancel()
+	}
+
+	return r, cancel, nil
+}
+
+// ReadPiece is used to read an Unsealed piece at the given offset and of the given size from a Sector
+// If an Unsealed sector file exists with the Piece Unsealed in it, we'll use that for the read.
+// Otherwise, we will Unseal a Sealed sector file for the given sector and read the Unsealed piece from it.
+// If we do NOT have an existing unsealed file  containing the given piece thus causing us to schedule an Unseal,
+// the returned boolean parameter will be set to true.
+// If we have an existing unsealed file containing the given piece, the returned boolean will be set to false.
+func (p *pieceProvider) ReadPiece(ctx context.Context, sector storage.SectorRef, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize, ticket abi.SealRandomness, unsealed cid.Cid) (io.ReadCloser, bool, error) {
+	if err := offset.Valid(); err != nil {
+		return nil, false, xerrors.Errorf("offset is not valid: %w", err)
+	}
+	if err := size.Validate(); err != nil {
+		return nil, false, xerrors.Errorf("size is not a valid piece size: %w", err)
+	}
+
+	r, unlock, err := p.tryReadUnsealedPiece(ctx, sector, offset, size)
+
+	log.Debugf("result of first tryReadUnsealedPiece: r=%+v, err=%s", r, err)
+
+	if xerrors.Is(err, storiface.ErrSectorNotFound) {
+		log.Debugf("no unsealed sector file with unsealed piece, sector=%+v, offset=%d, size=%d", sector, offset, size)
+		err = nil
+	}
+	if err != nil {
+		log.Errorf("returning error from ReadPiece:%s", err)
+		return nil, false, err
+	}
+
+	var uns bool
+
+	if r == nil {
+		// a nil reader means that none of the workers has an unsealed sector file
+		// containing the unsealed piece.
+		// we now need to unseal a sealed sector file for the given sector to read the unsealed piece from it.
+		uns = true
+		commd := &unsealed
+		if unsealed == cid.Undef {
+			commd = nil
+		}
+		if err := p.uns.SectorsUnsealPiece(ctx, sector, offset, size, ticket, commd); err != nil {
+			log.Errorf("failed to SectorsUnsealPiece: %s", err)
+			return nil, false, xerrors.Errorf("unsealing piece: %w", err)
+		}
+
+		log.Debugf("unsealed a sector file to read the piece, sector=%+v, offset=%d, size=%d", sector, offset, size)
+
+		r, unlock, err = p.tryReadUnsealedPiece(ctx, sector, offset, size)
+		if err != nil {
+			log.Errorf("failed to tryReadUnsealedPiece after SectorsUnsealPiece: %s", err)
+			return nil, true, xerrors.Errorf("read after unsealing: %w", err)
+		}
+		if r == nil {
+			log.Errorf("got no reader after unsealing piece")
+			return nil, true, xerrors.Errorf("got no reader after unsealing piece")
+		}
+		log.Debugf("got a reader to read unsealed piece, sector=%+v, offset=%d, size=%d", sector, offset, size)
+	} else {
+		log.Debugf("unsealed piece already exists, no need to unseal, sector=%+v, offset=%d, size=%d", sector, offset, size)
+	}
+
+	upr, err := fr32.NewUnpadReader(r, size.Padded())
+	if err != nil {
+		unlock()
+		return nil, uns, xerrors.Errorf("creating unpadded reader: %w", err)
+	}
+
+	log.Debugf("returning reader to read unsealed piece, sector=%+v, offset=%d, size=%d", sector, offset, size)
+
+	return &funcCloser{
+		Reader: bufio.NewReaderSize(upr, 127),
+		close: func() error {
+			err = r.Close()
+			unlock()
+			return err
+		},
+	}, uns, nil
+}
+
+type funcCloser struct {
+	io.Reader
+	close func() error
+}
+
+func (fc *funcCloser) Close() error { return fc.close() }
--- a/extern/sector-storage/piece_provider_test.go
+++ b/extern/sector-storage/piece_provider_test.go
@ -0,0 +1,332 @@
+package sectorstorage
+
+import (
+	"bytes"
+	"context"
+	"io/ioutil"
+	"math/rand"
+	"net"
+	"net/http"
+	"testing"
+
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/go-statestore"
+	"github.com/filecoin-project/lotus/extern/sector-storage/sealtasks"
+	specstorage "github.com/filecoin-project/specs-storage/storage"
+	"github.com/gorilla/mux"
+	"github.com/ipfs/go-cid"
+	"github.com/ipfs/go-datastore"
+	"github.com/ipfs/go-datastore/namespace"
+	ds_sync "github.com/ipfs/go-datastore/sync"
+	logging "github.com/ipfs/go-log/v2"
+	"github.com/stretchr/testify/require"
+
+	"github.com/filecoin-project/lotus/extern/sector-storage/stores"
+	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
+)
+
+// TestPieceProviderReadPiece verifies that the ReadPiece method works correctly
+// only uses miner and does NOT use any remote worker.
+func TestPieceProviderSimpleNoRemoteWorker(t *testing.T) {
+	// Set up sector storage manager
+	sealerCfg := SealerConfig{
+		ParallelFetchLimit: 10,
+		AllowAddPiece:      true,
+		AllowPreCommit1:    true,
+		AllowPreCommit2:    true,
+		AllowCommit:        true,
+		AllowUnseal:        true,
+	}
+
+	ppt := newPieceProviderTestHarness(t, sealerCfg, abi.RegisteredSealProof_StackedDrg8MiBV1)
+	defer ppt.shutdown(t)
+
+	// Create some padded data that aligns with the piece boundaries.
+	pieceData := generatePieceData(8 * 127 * 1024 * 8)
+	size := abi.UnpaddedPieceSize(len(pieceData))
+	ppt.addPiece(t, pieceData)
+
+	// read piece
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), size,
+		false, pieceData)
+
+	// pre-commit 1
+	preCommit1 := ppt.preCommit1(t)
+
+	// read piece
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), size,
+		false, pieceData)
+
+	// pre-commit 2
+	ppt.preCommit2(t, preCommit1)
+
+	// read piece
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), size,
+		false, pieceData)
+
+	// finalize -> nil here will remove unsealed file
+	ppt.finalizeSector(t, nil)
+
+	// Read the piece -> will have to unseal
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), size,
+		true, pieceData)
+
+	// read the piece -> will not have to unseal
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), size,
+		false, pieceData)
+
+}
+func TestReadPieceRemoteWorkers(t *testing.T) {
+	logging.SetAllLoggers(logging.LevelDebug)
+
+	// miner's worker can only add pieces to an unsealed sector.
+	sealerCfg := SealerConfig{
+		ParallelFetchLimit: 10,
+		AllowAddPiece:      true,
+		AllowPreCommit1:    false,
+		AllowPreCommit2:    false,
+		AllowCommit:        false,
+		AllowUnseal:        false,
+	}
+
+	// test harness for an 8M sector.
+	ppt := newPieceProviderTestHarness(t, sealerCfg, abi.RegisteredSealProof_StackedDrg8MiBV1)
+	defer ppt.shutdown(t)
+
+	// worker 2 will ONLY help with the sealing by first fetching
+	// the unsealed file from the miner.
+	ppt.addRemoteWorker(t, []sealtasks.TaskType{
+		sealtasks.TTPreCommit1, sealtasks.TTPreCommit2, sealtasks.TTCommit1,
+		sealtasks.TTFetch, sealtasks.TTFinalize,
+	})
+
+	// create a worker that can ONLY unseal and fetch
+	ppt.addRemoteWorker(t, []sealtasks.TaskType{
+		sealtasks.TTUnseal, sealtasks.TTFetch,
+	})
+
+	// run the test
+
+	// add one piece that aligns with the padding/piece boundaries.
+	pd1 := generatePieceData(8 * 127 * 4 * 1024)
+	pi1 := ppt.addPiece(t, pd1)
+	pd1size := pi1.Size.Unpadded()
+
+	pd2 := generatePieceData(8 * 127 * 4 * 1024)
+	pi2 := ppt.addPiece(t, pd2)
+	pd2size := pi2.Size.Unpadded()
+
+	// pre-commit 1
+	pC1 := ppt.preCommit1(t)
+	// Read the piece -> no need to unseal
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), pd1size,
+		false, pd1)
+
+	// pre-commit 2
+	ppt.preCommit2(t, pC1)
+	// Read the piece -> no need to unseal
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), pd1size,
+		false, pd1)
+
+	// finalize the sector so we declare to the index we have the sealed file
+	// so the unsealing worker can later look it up and fetch it if needed
+	// sending nil here will remove all unsealed files after sector is finalized.
+	ppt.finalizeSector(t, nil)
+
+	// Read the piece -> have to unseal since we removed the file.
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), pd1size,
+		true, pd1)
+
+	// Read the same piece again -> will NOT have to unseal.
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), pd1size, false, pd1)
+
+	// remove the unsealed file and read again -> will have to unseal.
+	ppt.removeAllUnsealedSectorFiles(t)
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(0), pd1size,
+		true, pd1)
+
+	// Read Piece 2 -> no unsealing as it got unsealed above.
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(pd1size), pd2size, false, pd2)
+
+	// remove all unseal files -> Read Piece 2 -> will have to Unseal.
+	ppt.removeAllUnsealedSectorFiles(t)
+	ppt.readPiece(t, storiface.UnpaddedByteIndex(pd1size), pd2size, true, pd2)
+}
+
+type pieceProviderTestHarness struct {
+	ctx         context.Context
+	index       *stores.Index
+	pp          PieceProvider
+	sector      specstorage.SectorRef
+	mgr         *Manager
+	ticket      abi.SealRandomness
+	commD       cid.Cid
+	localStores []*stores.Local
+
+	servers []*http.Server
+
+	addedPieces []abi.PieceInfo
+}
+
+func generatePieceData(size uint64) []byte {
+	bz := make([]byte, size)
+	rand.Read(bz)
+	return bz
+}
+
+func newPieceProviderTestHarness(t *testing.T, mgrConfig SealerConfig, sectorProofType abi.RegisteredSealProof) *pieceProviderTestHarness {
+	ctx := context.Background()
+	// listen on tcp socket to create an http server later
+	address := "0.0.0.0:0"
+	nl, err := net.Listen("tcp", address)
+	require.NoError(t, err)
+
+	// create index, storage, local store & remote store.
+	index := stores.NewIndex()
+	storage := newTestStorage(t)
+	localStore, err := stores.NewLocal(ctx, storage, index, []string{"http://" + nl.Addr().String() + "/remote"})
+	require.NoError(t, err)
+	remoteStore := stores.NewRemote(localStore, index, nil, 6000, &stores.DefaultPartialFileHandler{})
+
+	// data stores for state tracking.
+	dstore := ds_sync.MutexWrap(datastore.NewMapDatastore())
+	wsts := statestore.New(namespace.Wrap(dstore, datastore.NewKey("/worker/calls")))
+	smsts := statestore.New(namespace.Wrap(dstore, datastore.NewKey("/stmgr/calls")))
+
+	mgr, err := New(ctx, localStore, remoteStore, storage, index, mgrConfig, wsts, smsts)
+	require.NoError(t, err)
+
+	// start a http server on the manager to serve sector file requests.
+	svc := &http.Server{
+		Addr:    nl.Addr().String(),
+		Handler: mgr,
+	}
+	go func() {
+		_ = svc.Serve(nl)
+	}()
+
+	pp := NewPieceProvider(remoteStore, index, mgr)
+
+	sector := specstorage.SectorRef{
+		ID: abi.SectorID{
+			Miner:  100,
+			Number: 10,
+		},
+		ProofType: sectorProofType,
+	}
+
+	ticket := abi.SealRandomness{9, 9, 9, 9, 9, 9, 9, 9}
+
+	ppt := &pieceProviderTestHarness{
+		ctx:    ctx,
+		index:  index,
+		pp:     pp,
+		sector: sector,
+		mgr:    mgr,
+		ticket: ticket,
+	}
+	ppt.servers = append(ppt.servers, svc)
+	ppt.localStores = append(ppt.localStores, localStore)
+	return ppt
+}
+
+func (p *pieceProviderTestHarness) addRemoteWorker(t *testing.T, tasks []sealtasks.TaskType) {
+	// start an http Server
+	address := "0.0.0.0:0"
+	nl, err := net.Listen("tcp", address)
+	require.NoError(t, err)
+
+	localStore, err := stores.NewLocal(p.ctx, newTestStorage(t), p.index, []string{"http://" + nl.Addr().String() + "/remote"})
+	require.NoError(t, err)
+
+	fh := &stores.FetchHandler{
+		Local:     localStore,
+		PfHandler: &stores.DefaultPartialFileHandler{},
+	}
+
+	mux := mux.NewRouter()
+	mux.PathPrefix("/remote").HandlerFunc(fh.ServeHTTP)
+	svc := &http.Server{
+		Addr:    nl.Addr().String(),
+		Handler: mux,
+	}
+
+	go func() {
+		_ = svc.Serve(nl)
+	}()
+
+	remote := stores.NewRemote(localStore, p.index, nil, 1000,
+		&stores.DefaultPartialFileHandler{})
+
+	dstore := ds_sync.MutexWrap(datastore.NewMapDatastore())
+	csts := statestore.New(namespace.Wrap(dstore, datastore.NewKey("/stmgr/calls")))
+
+	worker := newLocalWorker(nil, WorkerConfig{
+		TaskTypes: tasks,
+	}, remote, localStore, p.index, p.mgr, csts)
+
+	p.servers = append(p.servers, svc)
+	p.localStores = append(p.localStores, localStore)
+
+	// register self with manager
+	require.NoError(t, p.mgr.AddWorker(p.ctx, worker))
+}
+
+func (p *pieceProviderTestHarness) removeAllUnsealedSectorFiles(t *testing.T) {
+	for i := range p.localStores {
+		ls := p.localStores[i]
+		require.NoError(t, ls.Remove(p.ctx, p.sector.ID, storiface.FTUnsealed, false))
+	}
+}
+
+func (p *pieceProviderTestHarness) addPiece(t *testing.T, pieceData []byte) abi.PieceInfo {
+	var existing []abi.UnpaddedPieceSize
+	for _, pi := range p.addedPieces {
+		existing = append(existing, pi.Size.Unpadded())
+	}
+
+	size := abi.UnpaddedPieceSize(len(pieceData))
+	pieceInfo, err := p.mgr.AddPiece(p.ctx, p.sector, existing, size, bytes.NewReader(pieceData))
+	require.NoError(t, err)
+
+	p.addedPieces = append(p.addedPieces, pieceInfo)
+	return pieceInfo
+}
+
+func (p *pieceProviderTestHarness) preCommit1(t *testing.T) specstorage.PreCommit1Out {
+	preCommit1, err := p.mgr.SealPreCommit1(p.ctx, p.sector, p.ticket, p.addedPieces)
+	require.NoError(t, err)
+	return preCommit1
+}
+
+func (p *pieceProviderTestHarness) preCommit2(t *testing.T, pc1 specstorage.PreCommit1Out) {
+	sectorCids, err := p.mgr.SealPreCommit2(p.ctx, p.sector, pc1)
+	require.NoError(t, err)
+	commD := sectorCids.Unsealed
+	p.commD = commD
+}
+
+func (p *pieceProviderTestHarness) readPiece(t *testing.T, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize,
+	expectedHadToUnseal bool, expectedBytes []byte) {
+	rd, isUnsealed, err := p.pp.ReadPiece(p.ctx, p.sector, offset, size, p.ticket, p.commD)
+	require.NoError(t, err)
+	require.NotNil(t, rd)
+	require.Equal(t, expectedHadToUnseal, isUnsealed)
+	defer func() { _ = rd.Close() }()
+
+	// Make sure the input matches the output
+	readData, err := ioutil.ReadAll(rd)
+	require.NoError(t, err)
+	require.Equal(t, expectedBytes, readData)
+}
+
+func (p *pieceProviderTestHarness) finalizeSector(t *testing.T, keepUnseal []specstorage.Range) {
+	require.NoError(t, p.mgr.FinalizeSector(p.ctx, p.sector, keepUnseal))
+}
+
+func (p *pieceProviderTestHarness) shutdown(t *testing.T) {
+	for _, svc := range p.servers {
+		s := svc
+		require.NoError(t, s.Shutdown(p.ctx))
+	}
+}
--- a/extern/sector-storage/resources.go
+++ b/extern/sector-storage/resources.go
@ -313,7 +313,6 @@ var ResourceTable = map[sealtasks.TaskType]map[abi.RegisteredSealProof]Resources

 func init() {
 	ResourceTable[sealtasks.TTUnseal] = ResourceTable[sealtasks.TTPreCommit1] // TODO: measure accurately
-	ResourceTable[sealtasks.TTReadUnsealed] = ResourceTable[sealtasks.TTFetch]

 	// V1_1 is the same as V1
 	for _, m := range ResourceTable {
--- a/extern/sector-storage/sealtasks/task.go
+++ b/extern/sector-storage/sealtasks/task.go
@ -11,21 +11,19 @@ const (

 	TTFinalize TaskType = "seal/v0/finalize"

-	TTFetch        TaskType = "seal/v0/fetch"
-	TTUnseal       TaskType = "seal/v0/unseal"
-	TTReadUnsealed TaskType = "seal/v0/unsealread"
+	TTFetch  TaskType = "seal/v0/fetch"
+	TTUnseal TaskType = "seal/v0/unseal"
 )

 var order = map[TaskType]int{
-	TTAddPiece:     6, // least priority
-	TTPreCommit1:   5,
-	TTPreCommit2:   4,
-	TTCommit2:      3,
-	TTCommit1:      2,
-	TTUnseal:       1,
-	TTFetch:        -1,
-	TTReadUnsealed: -1,
-	TTFinalize:     -2, // most priority
+	TTAddPiece:   6, // least priority
+	TTPreCommit1: 5,
+	TTPreCommit2: 4,
+	TTCommit2:    3,
+	TTCommit1:    2,
+	TTUnseal:     1,
+	TTFetch:      -1,
+	TTFinalize:   -2, // most priority
 }

 var shortNames = map[TaskType]string{
@ -38,9 +36,8 @@ var shortNames = map[TaskType]string{

 	TTFinalize: "FIN",

-	TTFetch:        "GET",
-	TTUnseal:       "UNS",
-	TTReadUnsealed: "RD",
+	TTFetch:  "GET",
+	TTUnseal: "UNS",
 }

 func (a TaskType) MuchLess(b TaskType) (bool, bool) {
--- a/extern/sector-storage/stores/http_handler.go
+++ b/extern/sector-storage/stores/http_handler.go
@ -5,7 +5,10 @@ import (
 	"io"
 	"net/http"
 	"os"
+	"strconv"

+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/lotus/extern/sector-storage/partialfile"
 	"github.com/gorilla/mux"
 	logging "github.com/ipfs/go-log/v2"
 	"golang.org/x/xerrors"
@ -18,8 +21,32 @@ import (

 var log = logging.Logger("stores")

+var _ partialFileHandler = &DefaultPartialFileHandler{}
+
+// DefaultPartialFileHandler is the default implementation of the partialFileHandler interface.
+// This is probably the only implementation we'll ever use because the purpose of the
+// interface to is to mock out partial file related functionality during testing.
+type DefaultPartialFileHandler struct{}
+
+func (d *DefaultPartialFileHandler) OpenPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialfile.PartialFile, error) {
+	return partialfile.OpenPartialFile(maxPieceSize, path)
+}
+func (d *DefaultPartialFileHandler) HasAllocated(pf *partialfile.PartialFile, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (bool, error) {
+	return pf.HasAllocated(offset, size)
+}
+
+func (d *DefaultPartialFileHandler) Reader(pf *partialfile.PartialFile, offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (*os.File, error) {
+	return pf.Reader(offset, size)
+}
+
+// Close closes the partial file
+func (d *DefaultPartialFileHandler) Close(pf *partialfile.PartialFile) error {
+	return pf.Close()
+}
+
 type FetchHandler struct {
-	*Local
+	Local     Store
+	PfHandler partialFileHandler
 }

 func (handler *FetchHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { // /remote/
@ -29,6 +56,8 @@ func (handler *FetchHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	mux.HandleFunc("/remote/{type}/{id}", handler.remoteGetSector).Methods("GET")
 	mux.HandleFunc("/remote/{type}/{id}", handler.remoteDeleteSector).Methods("DELETE")

+	mux.HandleFunc("/remote/{type}/{id}/{spt}/allocated/{offset}/{size}", handler.remoteGetAllocated).Methods("GET")
+
 	mux.ServeHTTP(w, r)
 }

@ -54,6 +83,8 @@ func (handler *FetchHandler) remoteStatFs(w http.ResponseWriter, r *http.Request
 	}
 }

+// remoteGetSector returns the sector file/tared directory byte stream for the sectorID and sector file type sent in the request.
+// returns an error if it does NOT have the required sector file/dir.
 func (handler *FetchHandler) remoteGetSector(w http.ResponseWriter, r *http.Request) {
 	log.Infof("SERVE GET %s", r.URL)
 	vars := mux.Vars(r)
@ -73,7 +104,6 @@ func (handler *FetchHandler) remoteGetSector(w http.ResponseWriter, r *http.Requ
 	}

 	// The caller has a lock on this sector already, no need to get one here
-
 	// passing 0 spt because we don't allocate anything
 	si := storage.SectorRef{
 		ID:        id,
@ -82,7 +112,7 @@ func (handler *FetchHandler) remoteGetSector(w http.ResponseWriter, r *http.Requ

 	paths, _, err := handler.Local.AcquireSector(r.Context(), si, ft, storiface.FTNone, storiface.PathStorage, storiface.AcquireMove)
 	if err != nil {
-		log.Errorf("%+v", err)
+		log.Errorf("AcquireSector: %+v", err)
 		w.WriteHeader(500)
 		return
 	}
@ -98,37 +128,38 @@ func (handler *FetchHandler) remoteGetSector(w http.ResponseWriter, r *http.Requ

 	stat, err := os.Stat(path)
 	if err != nil {
-		log.Errorf("%+v", err)
+		log.Errorf("os.Stat: %+v", err)
 		w.WriteHeader(500)
 		return
 	}

-	var rd io.Reader
 	if stat.IsDir() {
-		rd, err = tarutil.TarDirectory(path)
+		if _, has := r.Header["Range"]; has {
+			log.Error("Range not supported on directories")
+			w.WriteHeader(500)
+			return
+		}
+
+		rd, err := tarutil.TarDirectory(path)
+		if err != nil {
+			log.Errorf("%+v", err)
+			w.WriteHeader(500)
+			return
+		}
+
 		w.Header().Set("Content-Type", "application/x-tar")
+		w.WriteHeader(200)
+		if _, err := io.CopyBuffer(w, rd, make([]byte, CopyBuf)); err != nil {
+			log.Errorf("%+v", err)
+			return
+		}
 	} else {
-		rd, err = os.OpenFile(path, os.O_RDONLY, 0644) // nolint
 		w.Header().Set("Content-Type", "application/octet-stream")
-	}
-	if err != nil {
-		log.Errorf("%+v", err)
-		w.WriteHeader(500)
-		return
-	}
-	if !stat.IsDir() {
-		defer func() {
-			if err := rd.(*os.File).Close(); err != nil {
-				log.Errorf("closing source file: %+v", err)
-			}
-		}()
+		// will do a ranged read over the file at the given path if the caller has asked for a ranged read in the request headers.
+		http.ServeFile(w, r, path)
 	}

-	w.WriteHeader(200)
-	if _, err := io.CopyBuffer(w, rd, make([]byte, CopyBuf)); err != nil {
-		log.Errorf("%+v", err)
-		return
-	}
+	log.Debugf("served sector file/dir, sectorID=%+v, fileType=%s, path=%s", id, ft, path)
 }

 func (handler *FetchHandler) remoteDeleteSector(w http.ResponseWriter, r *http.Request) {
@ -149,13 +180,120 @@ func (handler *FetchHandler) remoteDeleteSector(w http.ResponseWriter, r *http.R
 		return
 	}

-	if err := handler.Remove(r.Context(), id, ft, false); err != nil {
+	if err := handler.Local.Remove(r.Context(), id, ft, false); err != nil {
 		log.Errorf("%+v", err)
 		w.WriteHeader(500)
 		return
 	}
 }

+// remoteGetAllocated returns `http.StatusOK` if the worker already has an Unsealed sector file
+// containing the Unsealed piece sent in the request.
+// returns `http.StatusRequestedRangeNotSatisfiable` otherwise.
+func (handler *FetchHandler) remoteGetAllocated(w http.ResponseWriter, r *http.Request) {
+	log.Infof("SERVE Alloc check %s", r.URL)
+	vars := mux.Vars(r)
+
+	id, err := storiface.ParseSectorID(vars["id"])
+	if err != nil {
+		log.Errorf("parsing sectorID: %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+
+	ft, err := ftFromString(vars["type"])
+	if err != nil {
+		log.Errorf("ftFromString: %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+	if ft != storiface.FTUnsealed {
+		log.Errorf("/allocated only supports unsealed sector files")
+		w.WriteHeader(500)
+		return
+	}
+
+	spti, err := strconv.ParseInt(vars["spt"], 10, 64)
+	if err != nil {
+		log.Errorf("parsing spt: %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+	spt := abi.RegisteredSealProof(spti)
+	ssize, err := spt.SectorSize()
+	if err != nil {
+		log.Errorf("spt.SectorSize(): %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+
+	offi, err := strconv.ParseInt(vars["offset"], 10, 64)
+	if err != nil {
+		log.Errorf("parsing offset: %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+	szi, err := strconv.ParseInt(vars["size"], 10, 64)
+	if err != nil {
+		log.Errorf("parsing size: %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+
+	// The caller has a lock on this sector already, no need to get one here
+
+	// passing 0 spt because we don't allocate anything
+	si := storage.SectorRef{
+		ID:        id,
+		ProofType: 0,
+	}
+
+	// get the path of the local Unsealed file for the given sector.
+	// return error if we do NOT have it.
+	paths, _, err := handler.Local.AcquireSector(r.Context(), si, ft, storiface.FTNone, storiface.PathStorage, storiface.AcquireMove)
+	if err != nil {
+		log.Errorf("AcquireSector: %+v", err)
+		w.WriteHeader(500)
+		return
+	}
+
+	path := storiface.PathByType(paths, ft)
+	if path == "" {
+		log.Error("acquired path was empty")
+		w.WriteHeader(500)
+		return
+	}
+
+	// open the Unsealed file and check if it has the Unsealed sector for the piece at the given offset and size.
+	pf, err := handler.PfHandler.OpenPartialFile(abi.PaddedPieceSize(ssize), path)
+	if err != nil {
+		log.Error("opening partial file: ", err)
+		w.WriteHeader(500)
+		return
+	}
+	defer func() {
+		if err := pf.Close(); err != nil {
+			log.Error("closing partial file: ", err)
+		}
+	}()
+
+	has, err := handler.PfHandler.HasAllocated(pf, storiface.UnpaddedByteIndex(offi), abi.UnpaddedPieceSize(szi))
+	if err != nil {
+		log.Error("has allocated: ", err)
+		w.WriteHeader(500)
+		return
+	}
+
+	if has {
+		log.Debugf("returning ok: worker has unsealed file with unsealed piece, sector:%+v, offset:%d, size:%d", id, offi, szi)
+		w.WriteHeader(http.StatusOK)
+		return
+	}
+
+	log.Debugf("returning StatusRequestedRangeNotSatisfiable: worker does NOT have unsealed file with unsealed piece, sector:%+v, offset:%d, size:%d", id, offi, szi)
+	w.WriteHeader(http.StatusRequestedRangeNotSatisfiable)
+}
+
 func ftFromString(t string) (storiface.SectorFileType, error) {
 	switch t {
 	case storiface.FTUnsealed.String():
--- a/extern/sector-storage/stores/http_handler_test.go
+++ b/extern/sector-storage/stores/http_handler_test.go
@ -0,0 +1,457 @@
+package stores_test
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/lotus/extern/sector-storage/partialfile"
+	"github.com/filecoin-project/lotus/extern/sector-storage/stores"
+	"github.com/filecoin-project/lotus/extern/sector-storage/stores/mocks"
+	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
+	"github.com/filecoin-project/specs-storage/storage"
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/require"
+	"golang.org/x/xerrors"
+)
+
+func TestRemoteGetAllocated(t *testing.T) {
+
+	emptyPartialFile := &partialfile.PartialFile{}
+	pfPath := "path"
+	expectedSectorRef := storage.SectorRef{
+		ID: abi.SectorID{
+			Miner:  123,
+			Number: 123,
+		},
+		ProofType: 0,
+	}
+
+	validSectorName := fmt.Sprintf("s-t0%d-%d", 123, 123)
+	validSectorFileType := storiface.FTUnsealed.String()
+	validSectorType := "1"
+	sectorSize := abi.SealProofInfos[1].SectorSize
+
+	validOffset := "100"
+	validOffsetInt := 100
+
+	validSize := "1000"
+	validSizeInt := 1000
+
+	type pieceInfo struct {
+		sectorName string
+		fileType   string
+		sectorType string
+
+		// piece info
+		offset string
+		size   string
+	}
+	validPieceInfo := pieceInfo{
+		sectorName: validSectorName,
+		fileType:   validSectorFileType,
+		sectorType: validSectorType,
+		offset:     validOffset,
+		size:       validSize,
+	}
+
+	tcs := map[string]struct {
+		piFnc    func(pi *pieceInfo)
+		storeFnc func(s *mocks.MockStore)
+		pfFunc   func(s *mocks.MockpartialFileHandler)
+
+		// expectation
+		expectedStatusCode int
+	}{
+		"fails when sector name is invalid": {
+			piFnc: func(pi *pieceInfo) {
+				pi.sectorName = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+		},
+		"fails when file type is invalid": {
+			piFnc: func(pi *pieceInfo) {
+				pi.fileType = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+		},
+		"fails when sector proof type is invalid": {
+			piFnc: func(pi *pieceInfo) {
+				pi.sectorType = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+		},
+		"fails when offset is invalid": {
+			piFnc: func(pi *pieceInfo) {
+				pi.offset = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+		},
+		"fails when size is invalid": {
+			piFnc: func(pi *pieceInfo) {
+				pi.size = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+		},
+		"fails when errors out during acquiring unsealed sector file": {
+			expectedStatusCode: http.StatusInternalServerError,
+			storeFnc: func(l *mocks.MockStore) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: "path",
+				},
+					storiface.SectorPaths{}, xerrors.New("some error")).Times(1)
+			},
+		},
+		"fails when unsealed sector file is not found locally": {
+			expectedStatusCode: http.StatusInternalServerError,
+			storeFnc: func(l *mocks.MockStore) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{},
+					storiface.SectorPaths{}, nil).Times(1)
+			},
+		},
+		"fails when error while opening partial file": {
+			expectedStatusCode: http.StatusInternalServerError,
+			storeFnc: func(l *mocks.MockStore) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: pfPath,
+				},
+					storiface.SectorPaths{}, nil).Times(1)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				pf.EXPECT().OpenPartialFile(abi.PaddedPieceSize(sectorSize), pfPath).Return(&partialfile.PartialFile{},
+					xerrors.New("some error")).Times(1)
+			},
+		},
+
+		"fails when determining partial file allocation returns an error": {
+			expectedStatusCode: http.StatusInternalServerError,
+			storeFnc: func(l *mocks.MockStore) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: pfPath,
+				},
+					storiface.SectorPaths{}, nil).Times(1)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				pf.EXPECT().OpenPartialFile(abi.PaddedPieceSize(sectorSize), pfPath).Return(emptyPartialFile,
+					nil).Times(1)
+
+				pf.EXPECT().HasAllocated(emptyPartialFile, storiface.UnpaddedByteIndex(validOffsetInt),
+					abi.UnpaddedPieceSize(validSizeInt)).Return(true, xerrors.New("some error")).Times(1)
+			},
+		},
+		"StatusRequestedRangeNotSatisfiable when piece is NOT allocated in partial file": {
+			expectedStatusCode: http.StatusRequestedRangeNotSatisfiable,
+			storeFnc: func(l *mocks.MockStore) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: pfPath,
+				},
+					storiface.SectorPaths{}, nil).Times(1)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				pf.EXPECT().OpenPartialFile(abi.PaddedPieceSize(sectorSize), pfPath).Return(emptyPartialFile,
+					nil).Times(1)
+
+				pf.EXPECT().HasAllocated(emptyPartialFile, storiface.UnpaddedByteIndex(validOffsetInt),
+					abi.UnpaddedPieceSize(validSizeInt)).Return(false, nil).Times(1)
+			},
+		},
+		"OK when piece is allocated in partial file": {
+			expectedStatusCode: http.StatusOK,
+			storeFnc: func(l *mocks.MockStore) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: pfPath,
+				},
+					storiface.SectorPaths{}, nil).Times(1)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				pf.EXPECT().OpenPartialFile(abi.PaddedPieceSize(sectorSize), pfPath).Return(emptyPartialFile,
+					nil).Times(1)
+
+				pf.EXPECT().HasAllocated(emptyPartialFile, storiface.UnpaddedByteIndex(validOffsetInt),
+					abi.UnpaddedPieceSize(validSizeInt)).Return(true, nil).Times(1)
+			},
+		},
+	}
+
+	for name, tc := range tcs {
+		tc := tc
+		t.Run(name, func(t *testing.T) {
+			// create go mock controller here
+			mockCtrl := gomock.NewController(t)
+			// when test is done, assert expectations on all mock objects.
+			defer mockCtrl.Finish()
+
+			lstore := mocks.NewMockStore(mockCtrl)
+			pfhandler := mocks.NewMockpartialFileHandler(mockCtrl)
+
+			handler := &stores.FetchHandler{
+				lstore,
+				pfhandler,
+			}
+
+			// run http server
+			ts := httptest.NewServer(handler)
+			defer ts.Close()
+
+			pi := validPieceInfo
+
+			if tc.piFnc != nil {
+				tc.piFnc(&pi)
+			}
+
+			if tc.storeFnc != nil {
+				tc.storeFnc(lstore)
+			}
+			if tc.pfFunc != nil {
+				tc.pfFunc(pfhandler)
+			}
+
+			// call remoteGetAllocated
+			url := fmt.Sprintf("%s/remote/%s/%s/%s/allocated/%s/%s",
+				ts.URL,
+				pi.fileType,
+				pi.sectorName,
+				pi.sectorType,
+				pi.offset,
+				pi.size)
+			resp, err := http.Get(url)
+			require.NoError(t, err)
+			defer func() {
+				_ = resp.Body.Close()
+			}()
+
+			// assert expected status code
+			require.Equal(t, tc.expectedStatusCode, resp.StatusCode)
+		})
+	}
+}
+
+func TestRemoteGetSector(t *testing.T) {
+	str := "hello-world"
+	fileBytes := []byte(str)
+
+	validSectorName := fmt.Sprintf("s-t0%d-%d", 123, 123)
+	validSectorFileType := storiface.FTUnsealed.String()
+	expectedSectorRef := storage.SectorRef{
+		ID: abi.SectorID{
+			Miner:  123,
+			Number: 123,
+		},
+		ProofType: 0,
+	}
+
+	type sectorInfo struct {
+		sectorName string
+		fileType   string
+	}
+	validSectorInfo := sectorInfo{
+		sectorName: validSectorName,
+		fileType:   validSectorFileType,
+	}
+
+	tcs := map[string]struct {
+		siFnc    func(pi *sectorInfo)
+		storeFnc func(s *mocks.MockStore, path string)
+
+		// reading a file or a dir
+		isDir bool
+
+		// expectation
+		noResponseBytes       bool
+		expectedContentType   string
+		expectedStatusCode    int
+		expectedResponseBytes []byte
+	}{
+		"fails when sector name is invalid": {
+			siFnc: func(si *sectorInfo) {
+				si.sectorName = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+			noResponseBytes:    true,
+		},
+		"fails when file type is invalid": {
+			siFnc: func(si *sectorInfo) {
+				si.fileType = "invalid"
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+			noResponseBytes:    true,
+		},
+		"fails when error while acquiring sector file": {
+			storeFnc: func(l *mocks.MockStore, _ string) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: "path",
+				},
+					storiface.SectorPaths{}, xerrors.New("some error")).Times(1)
+			},
+			expectedStatusCode: http.StatusInternalServerError,
+			noResponseBytes:    true,
+		},
+		"fails when acquired sector file path is empty": {
+			expectedStatusCode: http.StatusInternalServerError,
+			storeFnc: func(l *mocks.MockStore, _ string) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{},
+					storiface.SectorPaths{}, nil).Times(1)
+			},
+			noResponseBytes: true,
+		},
+		"fails when acquired file does not exist": {
+			expectedStatusCode: http.StatusInternalServerError,
+			storeFnc: func(l *mocks.MockStore, _ string) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: "path",
+				},
+					storiface.SectorPaths{}, nil)
+			},
+			noResponseBytes: true,
+		},
+		"successfully read a sector file": {
+			storeFnc: func(l *mocks.MockStore, path string) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: path,
+				},
+					storiface.SectorPaths{}, nil)
+			},
+
+			noResponseBytes:       false,
+			expectedContentType:   "application/octet-stream",
+			expectedStatusCode:    200,
+			expectedResponseBytes: fileBytes,
+		},
+		"successfully read a sector dir": {
+			storeFnc: func(l *mocks.MockStore, path string) {
+
+				l.EXPECT().AcquireSector(gomock.Any(), expectedSectorRef, storiface.FTUnsealed,
+					storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+					Unsealed: path,
+				},
+					storiface.SectorPaths{}, nil)
+			},
+
+			isDir:                 true,
+			noResponseBytes:       false,
+			expectedContentType:   "application/x-tar",
+			expectedStatusCode:    200,
+			expectedResponseBytes: fileBytes,
+		},
+	}
+
+	for name, tc := range tcs {
+		tc := tc
+		t.Run(name, func(t *testing.T) {
+			mockCtrl := gomock.NewController(t)
+			// when test is done, assert expectations on all mock objects.
+			defer mockCtrl.Finish()
+			lstore := mocks.NewMockStore(mockCtrl)
+			pfhandler := mocks.NewMockpartialFileHandler(mockCtrl)
+
+			var path string
+
+			if !tc.isDir {
+				// create file
+				tempFile, err := ioutil.TempFile("", "TestRemoteGetSector-")
+				require.NoError(t, err)
+
+				defer func() {
+					_ = os.Remove(tempFile.Name())
+				}()
+
+				_, err = tempFile.Write(fileBytes)
+				require.NoError(t, err)
+				path = tempFile.Name()
+			} else {
+				// create dir with a file
+				tempFile2, err := ioutil.TempFile("", "TestRemoteGetSector-")
+				require.NoError(t, err)
+				defer func() {
+					_ = os.Remove(tempFile2.Name())
+				}()
+
+				stat, err := os.Stat(tempFile2.Name())
+				require.NoError(t, err)
+				tempDir, err := ioutil.TempDir("", "TestRemoteGetSector-")
+				require.NoError(t, err)
+
+				defer func() {
+					_ = os.RemoveAll(tempDir)
+				}()
+
+				require.NoError(t, os.Rename(tempFile2.Name(), filepath.Join(tempDir, stat.Name())))
+
+				path = tempDir
+			}
+
+			handler := &stores.FetchHandler{
+				lstore,
+				pfhandler,
+			}
+
+			// run http server
+			ts := httptest.NewServer(handler)
+			defer ts.Close()
+
+			si := validSectorInfo
+			if tc.siFnc != nil {
+				tc.siFnc(&si)
+			}
+
+			if tc.storeFnc != nil {
+				tc.storeFnc(lstore, path)
+			}
+
+			// call remoteGetAllocated
+			url := fmt.Sprintf("%s/remote/%s/%s",
+				ts.URL,
+				si.fileType,
+				si.sectorName,
+			)
+			resp, err := http.Get(url)
+			require.NoError(t, err)
+			defer func() {
+				_ = resp.Body.Close()
+			}()
+
+			bz, err := ioutil.ReadAll(resp.Body)
+			require.NoError(t, err)
+
+			// assert expected status code
+			require.Equal(t, tc.expectedStatusCode, resp.StatusCode)
+
+			if !tc.noResponseBytes {
+				if !tc.isDir {
+					require.EqualValues(t, tc.expectedResponseBytes, bz)
+				}
+			}
+
+			require.Equal(t, tc.expectedContentType, resp.Header.Get("Content-Type"))
+		})
+	}
+}
--- a/extern/sector-storage/stores/interface.go
+++ b/extern/sector-storage/stores/interface.go
@ -2,8 +2,10 @@ package stores

 import (
 	"context"
+	"os"

 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/lotus/extern/sector-storage/partialfile"

 	"github.com/filecoin-project/specs-storage/storage"

@ -11,6 +13,23 @@ import (
 	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
 )

+// PartialFileHandler helps mock out the partial file functionality during testing.
+type partialFileHandler interface {
+	// OpenPartialFile opens and returns a partial file at the given path and also verifies it has the given
+	// size
+	OpenPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialfile.PartialFile, error)
+
+	// HasAllocated returns true if the given partial file has an unsealed piece starting at the given offset with the given size.
+	// returns false otherwise.
+	HasAllocated(pf *partialfile.PartialFile, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (bool, error)
+
+	// Reader returns a file from which we can read the unsealed piece in the partial file.
+	Reader(pf *partialfile.PartialFile, offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (*os.File, error)
+
+	// Close closes the partial file
+	Close(pf *partialfile.PartialFile) error
+}
+
 type Store interface {
 	AcquireSector(ctx context.Context, s storage.SectorRef, existing storiface.SectorFileType, allocate storiface.SectorFileType, sealing storiface.PathType, op storiface.AcquireMode) (paths storiface.SectorPaths, stores storiface.SectorPaths, err error)
 	Remove(ctx context.Context, s abi.SectorID, types storiface.SectorFileType, force bool) error
@ -23,4 +42,6 @@ type Store interface {
 	MoveStorage(ctx context.Context, s storage.SectorRef, types storiface.SectorFileType) error

 	FsStat(ctx context.Context, id ID) (fsutil.FsStat, error)
+
+	Reserve(ctx context.Context, sid storage.SectorRef, ft storiface.SectorFileType, storageIDs storiface.SectorPaths, overheadTab map[storiface.SectorFileType]int) (func(), error)
 }
--- a/extern/sector-storage/stores/mocks/index.go
+++ b/extern/sector-storage/stores/mocks/index.go
@ -0,0 +1,169 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: index.go
+
+// Package mock_stores is a generated GoMock package.
+package mocks
+
+import (
+	context "context"
+	reflect "reflect"
+
+	abi "github.com/filecoin-project/go-state-types/abi"
+	fsutil "github.com/filecoin-project/lotus/extern/sector-storage/fsutil"
+	stores "github.com/filecoin-project/lotus/extern/sector-storage/stores"
+	storiface "github.com/filecoin-project/lotus/extern/sector-storage/storiface"
+	gomock "github.com/golang/mock/gomock"
+)
+
+// MockSectorIndex is a mock of SectorIndex interface.
+type MockSectorIndex struct {
+	ctrl     *gomock.Controller
+	recorder *MockSectorIndexMockRecorder
+}
+
+// MockSectorIndexMockRecorder is the mock recorder for MockSectorIndex.
+type MockSectorIndexMockRecorder struct {
+	mock *MockSectorIndex
+}
+
+// NewMockSectorIndex creates a new mock instance.
+func NewMockSectorIndex(ctrl *gomock.Controller) *MockSectorIndex {
+	mock := &MockSectorIndex{ctrl: ctrl}
+	mock.recorder = &MockSectorIndexMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockSectorIndex) EXPECT() *MockSectorIndexMockRecorder {
+	return m.recorder
+}
+
+// StorageAttach mocks base method.
+func (m *MockSectorIndex) StorageAttach(arg0 context.Context, arg1 stores.StorageInfo, arg2 fsutil.FsStat) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageAttach", arg0, arg1, arg2)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// StorageAttach indicates an expected call of StorageAttach.
+func (mr *MockSectorIndexMockRecorder) StorageAttach(arg0, arg1, arg2 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageAttach", reflect.TypeOf((*MockSectorIndex)(nil).StorageAttach), arg0, arg1, arg2)
+}
+
+// StorageBestAlloc mocks base method.
+func (m *MockSectorIndex) StorageBestAlloc(ctx context.Context, allocate storiface.SectorFileType, ssize abi.SectorSize, pathType storiface.PathType) ([]stores.StorageInfo, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageBestAlloc", ctx, allocate, ssize, pathType)
+	ret0, _ := ret[0].([]stores.StorageInfo)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// StorageBestAlloc indicates an expected call of StorageBestAlloc.
+func (mr *MockSectorIndexMockRecorder) StorageBestAlloc(ctx, allocate, ssize, pathType interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageBestAlloc", reflect.TypeOf((*MockSectorIndex)(nil).StorageBestAlloc), ctx, allocate, ssize, pathType)
+}
+
+// StorageDeclareSector mocks base method.
+func (m *MockSectorIndex) StorageDeclareSector(ctx context.Context, storageID stores.ID, s abi.SectorID, ft storiface.SectorFileType, primary bool) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageDeclareSector", ctx, storageID, s, ft, primary)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// StorageDeclareSector indicates an expected call of StorageDeclareSector.
+func (mr *MockSectorIndexMockRecorder) StorageDeclareSector(ctx, storageID, s, ft, primary interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageDeclareSector", reflect.TypeOf((*MockSectorIndex)(nil).StorageDeclareSector), ctx, storageID, s, ft, primary)
+}
+
+// StorageDropSector mocks base method.
+func (m *MockSectorIndex) StorageDropSector(ctx context.Context, storageID stores.ID, s abi.SectorID, ft storiface.SectorFileType) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageDropSector", ctx, storageID, s, ft)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// StorageDropSector indicates an expected call of StorageDropSector.
+func (mr *MockSectorIndexMockRecorder) StorageDropSector(ctx, storageID, s, ft interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageDropSector", reflect.TypeOf((*MockSectorIndex)(nil).StorageDropSector), ctx, storageID, s, ft)
+}
+
+// StorageFindSector mocks base method.
+func (m *MockSectorIndex) StorageFindSector(ctx context.Context, sector abi.SectorID, ft storiface.SectorFileType, ssize abi.SectorSize, allowFetch bool) ([]stores.SectorStorageInfo, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageFindSector", ctx, sector, ft, ssize, allowFetch)
+	ret0, _ := ret[0].([]stores.SectorStorageInfo)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// StorageFindSector indicates an expected call of StorageFindSector.
+func (mr *MockSectorIndexMockRecorder) StorageFindSector(ctx, sector, ft, ssize, allowFetch interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageFindSector", reflect.TypeOf((*MockSectorIndex)(nil).StorageFindSector), ctx, sector, ft, ssize, allowFetch)
+}
+
+// StorageInfo mocks base method.
+func (m *MockSectorIndex) StorageInfo(arg0 context.Context, arg1 stores.ID) (stores.StorageInfo, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageInfo", arg0, arg1)
+	ret0, _ := ret[0].(stores.StorageInfo)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// StorageInfo indicates an expected call of StorageInfo.
+func (mr *MockSectorIndexMockRecorder) StorageInfo(arg0, arg1 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageInfo", reflect.TypeOf((*MockSectorIndex)(nil).StorageInfo), arg0, arg1)
+}
+
+// StorageLock mocks base method.
+func (m *MockSectorIndex) StorageLock(ctx context.Context, sector abi.SectorID, read, write storiface.SectorFileType) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageLock", ctx, sector, read, write)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// StorageLock indicates an expected call of StorageLock.
+func (mr *MockSectorIndexMockRecorder) StorageLock(ctx, sector, read, write interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageLock", reflect.TypeOf((*MockSectorIndex)(nil).StorageLock), ctx, sector, read, write)
+}
+
+// StorageReportHealth mocks base method.
+func (m *MockSectorIndex) StorageReportHealth(arg0 context.Context, arg1 stores.ID, arg2 stores.HealthReport) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageReportHealth", arg0, arg1, arg2)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// StorageReportHealth indicates an expected call of StorageReportHealth.
+func (mr *MockSectorIndexMockRecorder) StorageReportHealth(arg0, arg1, arg2 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageReportHealth", reflect.TypeOf((*MockSectorIndex)(nil).StorageReportHealth), arg0, arg1, arg2)
+}
+
+// StorageTryLock mocks base method.
+func (m *MockSectorIndex) StorageTryLock(ctx context.Context, sector abi.SectorID, read, write storiface.SectorFileType) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "StorageTryLock", ctx, sector, read, write)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// StorageTryLock indicates an expected call of StorageTryLock.
+func (mr *MockSectorIndexMockRecorder) StorageTryLock(ctx, sector, read, write interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "StorageTryLock", reflect.TypeOf((*MockSectorIndex)(nil).StorageTryLock), ctx, sector, read, write)
+}
--- a/extern/sector-storage/stores/mocks/stores.go
+++ b/extern/sector-storage/stores/mocks/stores.go
@ -0,0 +1,212 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: interface.go
+
+// Package mock_stores is a generated GoMock package.
+package mocks
+
+import (
+	context "context"
+	os "os"
+	reflect "reflect"
+
+	abi "github.com/filecoin-project/go-state-types/abi"
+	fsutil "github.com/filecoin-project/lotus/extern/sector-storage/fsutil"
+	partialfile "github.com/filecoin-project/lotus/extern/sector-storage/partialfile"
+	stores "github.com/filecoin-project/lotus/extern/sector-storage/stores"
+	storiface "github.com/filecoin-project/lotus/extern/sector-storage/storiface"
+	storage "github.com/filecoin-project/specs-storage/storage"
+	gomock "github.com/golang/mock/gomock"
+)
+
+// MockpartialFileHandler is a mock of partialFileHandler interface.
+type MockpartialFileHandler struct {
+	ctrl     *gomock.Controller
+	recorder *MockpartialFileHandlerMockRecorder
+}
+
+// MockpartialFileHandlerMockRecorder is the mock recorder for MockpartialFileHandler.
+type MockpartialFileHandlerMockRecorder struct {
+	mock *MockpartialFileHandler
+}
+
+// NewMockpartialFileHandler creates a new mock instance.
+func NewMockpartialFileHandler(ctrl *gomock.Controller) *MockpartialFileHandler {
+	mock := &MockpartialFileHandler{ctrl: ctrl}
+	mock.recorder = &MockpartialFileHandlerMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockpartialFileHandler) EXPECT() *MockpartialFileHandlerMockRecorder {
+	return m.recorder
+}
+
+// Close mocks base method.
+func (m *MockpartialFileHandler) Close(pf *partialfile.PartialFile) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Close", pf)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// Close indicates an expected call of Close.
+func (mr *MockpartialFileHandlerMockRecorder) Close(pf interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Close", reflect.TypeOf((*MockpartialFileHandler)(nil).Close), pf)
+}
+
+// HasAllocated mocks base method.
+func (m *MockpartialFileHandler) HasAllocated(pf *partialfile.PartialFile, offset storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "HasAllocated", pf, offset, size)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// HasAllocated indicates an expected call of HasAllocated.
+func (mr *MockpartialFileHandlerMockRecorder) HasAllocated(pf, offset, size interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "HasAllocated", reflect.TypeOf((*MockpartialFileHandler)(nil).HasAllocated), pf, offset, size)
+}
+
+// OpenPartialFile mocks base method.
+func (m *MockpartialFileHandler) OpenPartialFile(maxPieceSize abi.PaddedPieceSize, path string) (*partialfile.PartialFile, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "OpenPartialFile", maxPieceSize, path)
+	ret0, _ := ret[0].(*partialfile.PartialFile)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// OpenPartialFile indicates an expected call of OpenPartialFile.
+func (mr *MockpartialFileHandlerMockRecorder) OpenPartialFile(maxPieceSize, path interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "OpenPartialFile", reflect.TypeOf((*MockpartialFileHandler)(nil).OpenPartialFile), maxPieceSize, path)
+}
+
+// Reader mocks base method.
+func (m *MockpartialFileHandler) Reader(pf *partialfile.PartialFile, offset storiface.PaddedByteIndex, size abi.PaddedPieceSize) (*os.File, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Reader", pf, offset, size)
+	ret0, _ := ret[0].(*os.File)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// Reader indicates an expected call of Reader.
+func (mr *MockpartialFileHandlerMockRecorder) Reader(pf, offset, size interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Reader", reflect.TypeOf((*MockpartialFileHandler)(nil).Reader), pf, offset, size)
+}
+
+// MockStore is a mock of Store interface.
+type MockStore struct {
+	ctrl     *gomock.Controller
+	recorder *MockStoreMockRecorder
+}
+
+// MockStoreMockRecorder is the mock recorder for MockStore.
+type MockStoreMockRecorder struct {
+	mock *MockStore
+}
+
+// NewMockStore creates a new mock instance.
+func NewMockStore(ctrl *gomock.Controller) *MockStore {
+	mock := &MockStore{ctrl: ctrl}
+	mock.recorder = &MockStoreMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockStore) EXPECT() *MockStoreMockRecorder {
+	return m.recorder
+}
+
+// AcquireSector mocks base method.
+func (m *MockStore) AcquireSector(ctx context.Context, s storage.SectorRef, existing, allocate storiface.SectorFileType, sealing storiface.PathType, op storiface.AcquireMode) (storiface.SectorPaths, storiface.SectorPaths, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "AcquireSector", ctx, s, existing, allocate, sealing, op)
+	ret0, _ := ret[0].(storiface.SectorPaths)
+	ret1, _ := ret[1].(storiface.SectorPaths)
+	ret2, _ := ret[2].(error)
+	return ret0, ret1, ret2
+}
+
+// AcquireSector indicates an expected call of AcquireSector.
+func (mr *MockStoreMockRecorder) AcquireSector(ctx, s, existing, allocate, sealing, op interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "AcquireSector", reflect.TypeOf((*MockStore)(nil).AcquireSector), ctx, s, existing, allocate, sealing, op)
+}
+
+// FsStat mocks base method.
+func (m *MockStore) FsStat(ctx context.Context, id stores.ID) (fsutil.FsStat, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "FsStat", ctx, id)
+	ret0, _ := ret[0].(fsutil.FsStat)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// FsStat indicates an expected call of FsStat.
+func (mr *MockStoreMockRecorder) FsStat(ctx, id interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "FsStat", reflect.TypeOf((*MockStore)(nil).FsStat), ctx, id)
+}
+
+// MoveStorage mocks base method.
+func (m *MockStore) MoveStorage(ctx context.Context, s storage.SectorRef, types storiface.SectorFileType) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "MoveStorage", ctx, s, types)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// MoveStorage indicates an expected call of MoveStorage.
+func (mr *MockStoreMockRecorder) MoveStorage(ctx, s, types interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "MoveStorage", reflect.TypeOf((*MockStore)(nil).MoveStorage), ctx, s, types)
+}
+
+// Remove mocks base method.
+func (m *MockStore) Remove(ctx context.Context, s abi.SectorID, types storiface.SectorFileType, force bool) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Remove", ctx, s, types, force)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// Remove indicates an expected call of Remove.
+func (mr *MockStoreMockRecorder) Remove(ctx, s, types, force interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Remove", reflect.TypeOf((*MockStore)(nil).Remove), ctx, s, types, force)
+}
+
+// RemoveCopies mocks base method.
+func (m *MockStore) RemoveCopies(ctx context.Context, s abi.SectorID, types storiface.SectorFileType) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "RemoveCopies", ctx, s, types)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// RemoveCopies indicates an expected call of RemoveCopies.
+func (mr *MockStoreMockRecorder) RemoveCopies(ctx, s, types interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "RemoveCopies", reflect.TypeOf((*MockStore)(nil).RemoveCopies), ctx, s, types)
+}
+
+// Reserve mocks base method.
+func (m *MockStore) Reserve(ctx context.Context, sid storage.SectorRef, ft storiface.SectorFileType, storageIDs storiface.SectorPaths, overheadTab map[storiface.SectorFileType]int) (func(), error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "Reserve", ctx, sid, ft, storageIDs, overheadTab)
+	ret0, _ := ret[0].(func())
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// Reserve indicates an expected call of Reserve.
+func (mr *MockStoreMockRecorder) Reserve(ctx, sid, ft, storageIDs, overheadTab interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Reserve", reflect.TypeOf((*MockStore)(nil).Reserve), ctx, sid, ft, storageIDs, overheadTab)
+}
--- a/extern/sector-storage/stores/remote.go
+++ b/extern/sector-storage/stores/remote.go
@ -3,6 +3,7 @@ package stores
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"math/bits"
@ -31,7 +32,7 @@ var FetchTempSubdir = "fetching"
 var CopyBuf = 1 << 20

 type Remote struct {
-	local *Local
+	local Store
 	index SectorIndex
 	auth  http.Header

@ -39,6 +40,8 @@ type Remote struct {

 	fetchLk  sync.Mutex
 	fetching map[abi.SectorID]chan struct{}
+
+	pfHandler partialFileHandler
 }

 func (r *Remote) RemoveCopies(ctx context.Context, s abi.SectorID, types storiface.SectorFileType) error {
@ -49,7 +52,7 @@ func (r *Remote) RemoveCopies(ctx context.Context, s abi.SectorID, types storifa
 	return r.local.RemoveCopies(ctx, s, types)
 }

-func NewRemote(local *Local, index SectorIndex, auth http.Header, fetchLimit int) *Remote {
+func NewRemote(local Store, index SectorIndex, auth http.Header, fetchLimit int, pfHandler partialFileHandler) *Remote {
 	return &Remote{
 		local: local,
 		index: index,
@ -57,7 +60,8 @@ func NewRemote(local *Local, index SectorIndex, auth http.Header, fetchLimit int

 		limit: make(chan struct{}, fetchLimit),

-		fetching: map[abi.SectorID]chan struct{}{},
+		fetching:  map[abi.SectorID]chan struct{}{},
+		pfHandler: pfHandler,
 	}
 }

@ -415,4 +419,185 @@ func (r *Remote) FsStat(ctx context.Context, id ID) (fsutil.FsStat, error) {
 	return out, nil
 }

+func (r *Remote) checkAllocated(ctx context.Context, url string, spt abi.RegisteredSealProof, offset, size abi.PaddedPieceSize) (bool, error) {
+	url = fmt.Sprintf("%s/%d/allocated/%d/%d", url, spt, offset.Unpadded(), size.Unpadded())
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return false, xerrors.Errorf("request: %w", err)
+	}
+	req.Header = r.auth.Clone()
+	req = req.WithContext(ctx)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return false, xerrors.Errorf("do request: %w", err)
+	}
+	defer resp.Body.Close() // nolint
+
+	switch resp.StatusCode {
+	case http.StatusOK:
+		return true, nil
+	case http.StatusRequestedRangeNotSatisfiable:
+		return false, nil
+	default:
+		return false, xerrors.Errorf("unexpected http response: %d", resp.StatusCode)
+	}
+}
+
+func (r *Remote) readRemote(ctx context.Context, url string, offset, size abi.PaddedPieceSize) (io.ReadCloser, error) {
+	if len(r.limit) >= cap(r.limit) {
+		log.Infof("Throttling remote read, %d already running", len(r.limit))
+	}
+
+	// TODO: Smarter throttling
+	//  * Priority (just going sequentially is still pretty good)
+	//  * Per interface
+	//  * Aware of remote load
+	select {
+	case r.limit <- struct{}{}:
+		defer func() { <-r.limit }()
+	case <-ctx.Done():
+		return nil, xerrors.Errorf("context error while waiting for fetch limiter: %w", ctx.Err())
+	}
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, xerrors.Errorf("request: %w", err)
+	}
+
+	if r.auth != nil {
+		req.Header = r.auth.Clone()
+	}
+	req.Header.Set("Range", fmt.Sprintf("bytes=%d-%d", offset, offset+size-1))
+	req = req.WithContext(ctx)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, xerrors.Errorf("do request: %w", err)
+	}
+
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusPartialContent {
+		resp.Body.Close() // nolint
+		return nil, xerrors.Errorf("non-200 code: %d", resp.StatusCode)
+	}
+
+	return resp.Body, nil
+}
+
+// Reader returns a reader for an unsealed piece at the given offset in the given sector.
+// If the Miner has the unsealed piece locally, it will return a reader that reads from the local copy.
+// If the Miner does NOT have the unsealed piece locally, it will query all workers that have the unsealed sector file
+// to know if they have the unsealed piece and will then read the unsealed piece data from a worker that has it.
+//
+// Returns a nil reader if :
+// 1. no worker(local worker included) has an unsealed file for the given sector OR
+// 2. no worker(local worker included) has the unsealed piece in their unsealed sector file.
+// Will return a nil reader and a nil error in such a case.
+func (r *Remote) Reader(ctx context.Context, s storage.SectorRef, offset, size abi.PaddedPieceSize) (io.ReadCloser, error) {
+	ft := storiface.FTUnsealed
+
+	// check if we have the unsealed sector file locally
+	paths, _, err := r.local.AcquireSector(ctx, s, ft, storiface.FTNone, storiface.PathStorage, storiface.AcquireMove)
+	if err != nil {
+		return nil, xerrors.Errorf("acquire local: %w", err)
+	}
+
+	path := storiface.PathByType(paths, ft)
+
+	if path != "" {
+		// if we have the unsealed file locally, return a reader that can be used to read the contents of the
+		// unsealed piece.
+		log.Infof("Read local %s (+%d,%d)", path, offset, size)
+		ssize, err := s.ProofType.SectorSize()
+		if err != nil {
+			return nil, err
+		}
+		log.Debugf("fetched sector size %s (+%d,%d)", path, offset, size)
+
+		// open the unsealed sector file for the given sector size located at the given path.
+		pf, err := r.pfHandler.OpenPartialFile(abi.PaddedPieceSize(ssize), path)
+		if err != nil {
+			return nil, xerrors.Errorf("opening partial file: %w", err)
+		}
+		log.Debugf("local partial file opened %s (+%d,%d)", path, offset, size)
+
+		// even though we have an unsealed file for the given sector, we still need to determine if we have the unsealed piece
+		// in the unsealed sector file. That is what `HasAllocated` checks for.
+		has, err := r.pfHandler.HasAllocated(pf, storiface.UnpaddedByteIndex(offset.Unpadded()), size.Unpadded())
+		if err != nil {
+			return nil, xerrors.Errorf("has allocated: %w", err)
+		}
+		log.Debugf("check if partial file is allocated %s (+%d,%d)", path, offset, size)
+
+		if !has {
+			log.Debugf("miner has unsealed file but not unseal piece, %s (+%d,%d)", path, offset, size)
+			if err := r.pfHandler.Close(pf); err != nil {
+				return nil, xerrors.Errorf("close partial file: %w", err)
+			}
+			return nil, nil
+		}
+
+		log.Infof("returning piece reader for local unsealed piece sector=%+v, (offset=%d, size=%d)", s.ID, offset, size)
+		return r.pfHandler.Reader(pf, storiface.PaddedByteIndex(offset), size)
+	}
+
+	// --- We don't have the unsealed sector file locally
+
+	// if we don't have the unsealed sector file locally, we'll first lookup the Miner Sector Store Index
+	// to determine which workers have the unsealed file and then query those workers to know
+	// if they have the unsealed piece in the unsealed sector file.
+	si, err := r.index.StorageFindSector(ctx, s.ID, ft, 0, false)
+	if err != nil {
+		log.Debugf("Reader, did not find unsealed file on any of the workers %s (+%d,%d)", path, offset, size)
+		return nil, err
+	}
+
+	if len(si) == 0 {
+		return nil, xerrors.Errorf("failed to read sector %v from remote(%d): %w", s, ft, storiface.ErrSectorNotFound)
+	}
+
+	sort.Slice(si, func(i, j int) bool {
+		return si[i].Weight > si[j].Weight
+	})
+
+	var lastErr error
+	for _, info := range si {
+		for _, url := range info.URLs {
+			// checkAllocated makes a JSON RPC query to a remote worker to determine if it has
+			// unsealed piece in their unsealed sector file.
+			ok, err := r.checkAllocated(ctx, url, s.ProofType, offset, size)
+			if err != nil {
+				log.Warnw("check if remote has piece", "url", url, "error", err)
+				lastErr = err
+				continue
+			}
+			if !ok {
+				continue
+			}
+
+			// readRemote fetches a reader that we can use to read the unsealed piece from the remote worker.
+			// It uses a ranged HTTP query to ensure we ONLY read the unsealed piece and not the entire unsealed file.
+			rd, err := r.readRemote(ctx, url, offset, size)
+			if err != nil {
+				log.Warnw("reading from remote", "url", url, "error", err)
+				lastErr = err
+				continue
+			}
+			log.Infof("Read remote %s (+%d,%d)", url, offset, size)
+			return rd, nil
+		}
+	}
+
+	// we couldn't find a unsealed file with the unsealed piece, will return a nil reader.
+	log.Debugf("returning nil reader, did not find unsealed piece for %+v (+%d,%d), last error=%s", s, offset, size, lastErr)
+	return nil, nil
+}
+
+func (r *Remote) Reserve(ctx context.Context, sid storage.SectorRef, ft storiface.SectorFileType, storageIDs storiface.SectorPaths, overheadTab map[storiface.SectorFileType]int) (func(), error) {
+	log.Warnf("reserve called on remote store, sectorID: %v", sid.ID)
+	return func() {
+
+	}, nil
+}
+
 var _ Store = &Remote{}
--- a/extern/sector-storage/stores/remote_test.go
+++ b/extern/sector-storage/stores/remote_test.go
@ -0,0 +1,418 @@
+package stores_test
+
+import (
+	"context"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/lotus/extern/sector-storage/partialfile"
+	"github.com/filecoin-project/lotus/extern/sector-storage/stores"
+	"github.com/filecoin-project/lotus/extern/sector-storage/stores/mocks"
+	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
+	"github.com/filecoin-project/specs-storage/storage"
+	"github.com/golang/mock/gomock"
+	"github.com/gorilla/mux"
+	logging "github.com/ipfs/go-log/v2"
+	"github.com/stretchr/testify/require"
+	"golang.org/x/xerrors"
+)
+
+func TestReader(t *testing.T) {
+	logging.SetAllLoggers(logging.LevelDebug)
+	bz := []byte("Hello World")
+
+	pfPath := "path"
+	ft := storiface.FTUnsealed
+	emptyPartialFile := &partialfile.PartialFile{}
+
+	sectorRef := storage.SectorRef{
+		ID: abi.SectorID{
+			Miner:  123,
+			Number: 123,
+		},
+		ProofType: 1,
+	}
+	sectorSize := abi.SealProofInfos[1].SectorSize
+
+	offset := abi.PaddedPieceSize(100)
+	size := abi.PaddedPieceSize(1000)
+	ctx := context.Background()
+
+	tcs := map[string]struct {
+		storeFnc func(s *mocks.MockStore)
+		pfFunc   func(s *mocks.MockpartialFileHandler)
+		indexFnc func(s *mocks.MockSectorIndex, serverURL string)
+
+		needHttpServer bool
+
+		getAllocatedReturnCode int
+		getSectorReturnCode    int
+
+		serverUrl string
+
+		// expectation
+		errStr               string
+		expectedNonNilReader bool
+		expectedSectorBytes  []byte
+	}{
+
+		// -------- have the unsealed file locally
+		"fails when error while acquiring unsealed file": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, xerrors.New("acquire error"))
+			},
+
+			errStr: "acquire error",
+		},
+
+		"fails when error while opening local partial (unsealed) file": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, nil)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				mockPartialFileOpen(pf, sectorSize, pfPath, xerrors.New("pf open error"))
+			},
+			errStr: "pf open error",
+		},
+
+		"fails when error while checking if local unsealed file has piece": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, nil)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				mockPartialFileOpen(pf, sectorSize, pfPath, nil)
+				mockCheckAllocation(pf, offset, size, emptyPartialFile,
+					true, xerrors.New("piece check error"))
+			},
+
+			errStr: "piece check error",
+		},
+
+		"fails when error while closing local unsealed file that does not have the piece": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, nil)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				mockPartialFileOpen(pf, sectorSize, pfPath, nil)
+				mockCheckAllocation(pf, offset, size, emptyPartialFile,
+					false, nil)
+				pf.EXPECT().Close(emptyPartialFile).Return(xerrors.New("close error")).Times(1)
+			},
+			errStr: "close error",
+		},
+
+		"fails when error while fetching reader for the local unsealed file that has the unsealed piece": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, nil)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				mockPartialFileOpen(pf, sectorSize, pfPath, nil)
+				mockCheckAllocation(pf, offset, size, emptyPartialFile,
+					true, nil)
+				mockPfReader(pf, emptyPartialFile, offset, size, nil, xerrors.New("reader error"))
+
+			},
+			errStr: "reader error",
+		},
+
+		// ------------------- don't have the unsealed file locally
+
+		"fails when error while finding sector": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, "", nil)
+			},
+
+			indexFnc: func(in *mocks.MockSectorIndex, _ string) {
+				in.EXPECT().StorageFindSector(gomock.Any(), sectorRef.ID, storiface.FTUnsealed, gomock.Any(),
+					false).Return(nil, xerrors.New("find sector error"))
+			},
+			errStr: "find sector error",
+		},
+
+		"fails when no worker has unsealed file": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, "", nil)
+			},
+
+			indexFnc: func(in *mocks.MockSectorIndex, _ string) {
+				in.EXPECT().StorageFindSector(gomock.Any(), sectorRef.ID, storiface.FTUnsealed, gomock.Any(),
+					false).Return(nil, nil)
+			},
+			errStr: storiface.ErrSectorNotFound.Error(),
+		},
+
+		// --- nil reader when local unsealed file does NOT have unsealed piece
+		"nil reader when local unsealed file does not have the piece": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, nil)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				mockPartialFileOpen(pf, sectorSize, pfPath, nil)
+				mockCheckAllocation(pf, offset, size, emptyPartialFile,
+					false, nil)
+
+				pf.EXPECT().Close(emptyPartialFile).Return(nil).Times(1)
+			},
+		},
+
+		// ---- nil reader when none of the remote unsealed file has unsealed piece
+		"nil reader when none of the worker has the unsealed piece": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, "", nil)
+			},
+
+			indexFnc: func(in *mocks.MockSectorIndex, url string) {
+				si := stores.SectorStorageInfo{
+					URLs: []string{url},
+				}
+
+				in.EXPECT().StorageFindSector(gomock.Any(), sectorRef.ID, storiface.FTUnsealed, gomock.Any(),
+					false).Return([]stores.SectorStorageInfo{si}, nil).Times(1)
+			},
+
+			needHttpServer:         true,
+			getAllocatedReturnCode: 500,
+		},
+
+		"nil reader when none of the worker is able to serve the unsealed piece even though they have it": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, "", nil)
+			},
+
+			indexFnc: func(in *mocks.MockSectorIndex, url string) {
+				si := stores.SectorStorageInfo{
+					URLs: []string{url},
+				}
+
+				in.EXPECT().StorageFindSector(gomock.Any(), sectorRef.ID, storiface.FTUnsealed, gomock.Any(),
+					false).Return([]stores.SectorStorageInfo{si}, nil).Times(1)
+			},
+
+			needHttpServer:         true,
+			getSectorReturnCode:    500,
+			getAllocatedReturnCode: 200,
+		},
+
+		// ---- Success for local unsealed file
+		"successfully fetches reader for piece from local unsealed file": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, pfPath, nil)
+			},
+
+			pfFunc: func(pf *mocks.MockpartialFileHandler) {
+				mockPartialFileOpen(pf, sectorSize, pfPath, nil)
+				mockCheckAllocation(pf, offset, size, emptyPartialFile,
+					true, nil)
+
+				f, err := ioutil.TempFile("", "TestReader-")
+				require.NoError(t, err)
+				_, err = f.Write(bz)
+				require.NoError(t, err)
+				require.NoError(t, f.Close())
+				f, err = os.Open(f.Name())
+				require.NoError(t, err)
+
+				mockPfReader(pf, emptyPartialFile, offset, size, f, nil)
+
+			},
+
+			expectedNonNilReader: true,
+			expectedSectorBytes:  bz,
+		},
+
+		// --- Success for remote unsealed file
+		"successfully fetches reader for piece from remote unsealed piece": {
+			storeFnc: func(l *mocks.MockStore) {
+				mockSectorAcquire(l, sectorRef, "", nil)
+			},
+
+			indexFnc: func(in *mocks.MockSectorIndex, url string) {
+				si := stores.SectorStorageInfo{
+					URLs: []string{url},
+				}
+
+				in.EXPECT().StorageFindSector(gomock.Any(), sectorRef.ID, storiface.FTUnsealed, gomock.Any(),
+					false).Return([]stores.SectorStorageInfo{si}, nil).Times(1)
+			},
+
+			needHttpServer:         true,
+			getSectorReturnCode:    200,
+			getAllocatedReturnCode: 200,
+			expectedSectorBytes:    bz,
+			expectedNonNilReader:   true,
+		},
+	}
+
+	for name, tc := range tcs {
+		tc := tc
+		t.Run(name, func(t *testing.T) {
+			// create go mock controller here
+			mockCtrl := gomock.NewController(t)
+			// when test is done, assert expectations on all mock objects.
+			defer mockCtrl.Finish()
+
+			// create them mocks
+			lstore := mocks.NewMockStore(mockCtrl)
+			pfhandler := mocks.NewMockpartialFileHandler(mockCtrl)
+			index := mocks.NewMockSectorIndex(mockCtrl)
+
+			if tc.storeFnc != nil {
+				tc.storeFnc(lstore)
+			}
+			if tc.pfFunc != nil {
+				tc.pfFunc(pfhandler)
+			}
+
+			if tc.needHttpServer {
+				// run http server
+				ts := httptest.NewServer(&mockHttpServer{
+					expectedSectorName: storiface.SectorName(sectorRef.ID),
+					expectedFileType:   ft.String(),
+					expectedOffset:     fmt.Sprintf("%d", offset.Unpadded()),
+					expectedSize:       fmt.Sprintf("%d", size.Unpadded()),
+					expectedSectorType: fmt.Sprintf("%d", sectorRef.ProofType),
+
+					getAllocatedReturnCode: tc.getAllocatedReturnCode,
+					getSectorReturnCode:    tc.getSectorReturnCode,
+					getSectorBytes:         tc.expectedSectorBytes,
+				})
+				defer ts.Close()
+				tc.serverUrl = fmt.Sprintf("%s/remote/%s/%s", ts.URL, ft.String(), storiface.SectorName(sectorRef.ID))
+			}
+			if tc.indexFnc != nil {
+				tc.indexFnc(index, tc.serverUrl)
+			}
+
+			remoteStore := stores.NewRemote(lstore, index, nil, 6000, pfhandler)
+
+			rd, err := remoteStore.Reader(ctx, sectorRef, offset, size)
+
+			if tc.errStr != "" {
+				require.Error(t, err)
+				require.Nil(t, rd)
+				require.Contains(t, err.Error(), tc.errStr)
+			} else {
+				require.NoError(t, err)
+			}
+
+			if !tc.expectedNonNilReader {
+				require.Nil(t, rd)
+			} else {
+				require.NotNil(t, rd)
+				defer func() {
+					require.NoError(t, rd.Close())
+				}()
+
+				if f, ok := rd.(*os.File); ok {
+					require.NoError(t, os.Remove(f.Name()))
+				}
+
+				bz, err := ioutil.ReadAll(rd)
+				require.NoError(t, err)
+				require.Equal(t, tc.expectedSectorBytes, bz)
+			}
+
+		})
+	}
+}
+
+func mockSectorAcquire(l *mocks.MockStore, sectorRef storage.SectorRef, pfPath string, err error) {
+	l.EXPECT().AcquireSector(gomock.Any(), sectorRef, storiface.FTUnsealed,
+		storiface.FTNone, storiface.PathStorage, storiface.AcquireMove).Return(storiface.SectorPaths{
+		Unsealed: pfPath,
+	},
+		storiface.SectorPaths{}, err).Times(1)
+}
+
+func mockPartialFileOpen(pf *mocks.MockpartialFileHandler, sectorSize abi.SectorSize, pfPath string, err error) {
+	pf.EXPECT().OpenPartialFile(abi.PaddedPieceSize(sectorSize), pfPath).Return(&partialfile.PartialFile{},
+		err).Times(1)
+}
+
+func mockCheckAllocation(pf *mocks.MockpartialFileHandler, offset, size abi.PaddedPieceSize, file *partialfile.PartialFile,
+	out bool, err error) {
+	pf.EXPECT().HasAllocated(file, storiface.UnpaddedByteIndex(offset.Unpadded()),
+		size.Unpadded()).Return(out, err).Times(1)
+}
+
+func mockPfReader(pf *mocks.MockpartialFileHandler, file *partialfile.PartialFile, offset, size abi.PaddedPieceSize,
+	outFile *os.File, err error) {
+	pf.EXPECT().Reader(file, storiface.PaddedByteIndex(offset), size).Return(outFile, err)
+}
+
+type mockHttpServer struct {
+	expectedSectorName string
+	expectedFileType   string
+	expectedOffset     string
+	expectedSize       string
+	expectedSectorType string
+
+	getAllocatedReturnCode int
+	getSectorReturnCode    int
+	getSectorBytes         []byte
+}
+
+func (m *mockHttpServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	mux := mux.NewRouter()
+	mux.HandleFunc("/remote/{type}/{id}", m.getSector).Methods("GET")
+	mux.HandleFunc("/remote/{type}/{id}/{spt}/allocated/{offset}/{size}", m.getAllocated).Methods("GET")
+	mux.ServeHTTP(w, r)
+}
+
+func (m *mockHttpServer) getAllocated(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+
+	if vars["id"] != m.expectedSectorName {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	if vars["type"] != m.expectedFileType {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	if vars["spt"] != m.expectedSectorType {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	if vars["offset"] != m.expectedOffset {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	if vars["size"] != m.expectedSize {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	w.WriteHeader(m.getAllocatedReturnCode)
+}
+
+func (m *mockHttpServer) getSector(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+
+	if vars["id"] != m.expectedSectorName {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	if vars["type"] != m.expectedFileType {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	w.WriteHeader(m.getSectorReturnCode)
+	_, _ = w.Write(m.getSectorBytes)
+}
--- a/extern/sector-storage/stores/util_unix.go
+++ b/extern/sector-storage/stores/util_unix.go
@ -2,8 +2,10 @@ package stores

 import (
 	"bytes"
+	"os"
 	"os/exec"
 	"path/filepath"
+	"runtime"
 	"strings"

 	"github.com/mitchellh/go-homedir"
@ -33,7 +35,18 @@ func move(from, to string) error {
 	//  can do better

 	var errOut bytes.Buffer
-	cmd := exec.Command("/usr/bin/env", "mv", "-t", toDir, from) // nolint
+
+	var cmd *exec.Cmd
+	if runtime.GOOS == "darwin" {
+		if err := os.MkdirAll(toDir, 0777); err != nil {
+			return xerrors.Errorf("failed exec MkdirAll: %s", err)
+		}
+
+		cmd = exec.Command("/usr/bin/env", "mv", from, toDir) // nolint
+	} else {
+		cmd = exec.Command("/usr/bin/env", "mv", "-t", toDir, from) // nolint
+	}
+
 	cmd.Stderr = &errOut
 	if err := cmd.Run(); err != nil {
 		return xerrors.Errorf("exec mv (stderr: %s): %w", strings.TrimSpace(errOut.String()), err)
--- a/extern/sector-storage/storiface/ffi.go
+++ b/extern/sector-storage/storiface/ffi.go
@ -5,6 +5,7 @@ import (
 	"errors"

 	"github.com/ipfs/go-cid"
+	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-state-types/abi"
 )
@ -17,6 +18,14 @@ func (i UnpaddedByteIndex) Padded() PaddedByteIndex {
 	return PaddedByteIndex(abi.UnpaddedPieceSize(i).Padded())
 }

+func (i UnpaddedByteIndex) Valid() error {
+	if i%127 != 0 {
+		return xerrors.Errorf("unpadded byte index must be a multiple of 127")
+	}
+
+	return nil
+}
+
 type PaddedByteIndex uint64

 type RGetter func(ctx context.Context, id abi.SectorID) (cid.Cid, error)
--- a/extern/sector-storage/storiface/worker.go
+++ b/extern/sector-storage/storiface/worker.go
@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"io"
 	"time"

 	"github.com/google/uuid"
@ -87,7 +86,6 @@ type WorkerCalls interface {
 	ReleaseUnsealed(ctx context.Context, sector storage.SectorRef, safeToFree []storage.Range) (CallID, error)
 	MoveStorage(ctx context.Context, sector storage.SectorRef, types SectorFileType) (CallID, error)
 	UnsealPiece(context.Context, storage.SectorRef, UnpaddedByteIndex, abi.UnpaddedPieceSize, abi.SealRandomness, cid.Cid) (CallID, error)
-	ReadPiece(context.Context, io.Writer, storage.SectorRef, UnpaddedByteIndex, abi.UnpaddedPieceSize) (CallID, error)
 	Fetch(context.Context, storage.SectorRef, SectorFileType, PathType, AcquireMode) (CallID, error)
 }

--- a/extern/sector-storage/worker_local.go
+++ b/extern/sector-storage/worker_local.go
@ -161,7 +161,6 @@ const (
 	ReleaseUnsealed ReturnType = "ReleaseUnsealed"
 	MoveStorage     ReturnType = "MoveStorage"
 	UnsealPiece     ReturnType = "UnsealPiece"
-	ReadPiece       ReturnType = "ReadPiece"
 	Fetch           ReturnType = "Fetch"
 )

@ -209,7 +208,6 @@ var returnFunc = map[ReturnType]func(context.Context, storiface.CallID, storifac
 	ReleaseUnsealed: rfunc(storiface.WorkerReturn.ReturnReleaseUnsealed),
 	MoveStorage:     rfunc(storiface.WorkerReturn.ReturnMoveStorage),
 	UnsealPiece:     rfunc(storiface.WorkerReturn.ReturnUnsealPiece),
-	ReadPiece:       rfunc(storiface.WorkerReturn.ReturnReadPiece),
 	Fetch:           rfunc(storiface.WorkerReturn.ReturnFetch),
 }

@ -430,6 +428,7 @@ func (l *LocalWorker) UnsealPiece(ctx context.Context, sector storage.SectorRef,
 	}

 	return l.asyncCall(ctx, sector, UnsealPiece, func(ctx context.Context, ci storiface.CallID) (interface{}, error) {
+		log.Debugf("worker will unseal piece now, sector=%+v", sector.ID)
 		if err = sb.UnsealPiece(ctx, sector, index, size, randomness, cid); err != nil {
 			return nil, xerrors.Errorf("unsealing sector: %w", err)
 		}
@ -442,21 +441,12 @@ func (l *LocalWorker) UnsealPiece(ctx context.Context, sector storage.SectorRef,
 			return nil, xerrors.Errorf("removing source data: %w", err)
 		}

+		log.Debugf("worker has unsealed piece, sector=%+v", sector.ID)
+
 		return nil, nil
 	})
 }

-func (l *LocalWorker) ReadPiece(ctx context.Context, writer io.Writer, sector storage.SectorRef, index storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (storiface.CallID, error) {
-	sb, err := l.executor()
-	if err != nil {
-		return storiface.UndefCall, err
-	}
-
-	return l.asyncCall(ctx, sector, ReadPiece, func(ctx context.Context, ci storiface.CallID) (interface{}, error) {
-		return sb.ReadPiece(ctx, writer, sector, index, size)
-	})
-}
-
 func (l *LocalWorker) TaskTypes(context.Context) (map[sealtasks.TaskType]struct{}, error) {
 	l.taskLk.Lock()
 	defer l.taskLk.Unlock()
--- a/extern/sector-storage/worker_tracked.go
+++ b/extern/sector-storage/worker_tracked.go
@ -2,7 +2,6 @@ package sectorstorage

 import (
 	"context"
-	"io"
 	"sync"
 	"time"

@ -156,8 +155,4 @@ func (t *trackedWorker) UnsealPiece(ctx context.Context, id storage.SectorRef, i
 	return t.tracker.track(ctx, t.wid, t.workerInfo, id, sealtasks.TTUnseal)(t.Worker.UnsealPiece(ctx, id, index, size, randomness, cid))
 }

-func (t *trackedWorker) ReadPiece(ctx context.Context, writer io.Writer, id storage.SectorRef, index storiface.UnpaddedByteIndex, size abi.UnpaddedPieceSize) (storiface.CallID, error) {
-	return t.tracker.track(ctx, t.wid, t.workerInfo, id, sealtasks.TTReadUnsealed)(t.Worker.ReadPiece(ctx, writer, id, index, size))
-}
-
 var _ Worker = &trackedWorker{}
--- a/go.mod
+++ b/go.mod
@ -55,7 +55,7 @@ require (
 	github.com/gdamore/tcell/v2 v2.2.0
 	github.com/go-kit/kit v0.10.0
 	github.com/go-ole/go-ole v1.2.4 // indirect
-	github.com/golang/mock v1.4.4
+	github.com/golang/mock v1.5.0
 	github.com/google/uuid v1.1.2
 	github.com/gorilla/mux v1.7.4
 	github.com/gorilla/websocket v1.4.2
--- a/go.sum
+++ b/go.sum
@ -416,8 +416,9 @@ github.com/golang/mock v1.2.0/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfb
 github.com/golang/mock v1.3.1/go.mod h1:sBzyDLLjw3U8JLTeZvSv8jJB+tU5PVekmnlKIyFUx0Y=
 github.com/golang/mock v1.4.0/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
 github.com/golang/mock v1.4.3/go.mod h1:UOMv5ysSaYNkG+OFQykRIcU/QvvxJf3p21QfJ2Bt3cw=
-github.com/golang/mock v1.4.4 h1:l75CXGRSwbaYNpl/Z2X1XIIAMSCquvXgpVZDhwEIJsc=
 github.com/golang/mock v1.4.4/go.mod h1:l3mdAwkq5BuhzHwde/uurv3sEJeZMXNpwsxVWU71h+4=
+github.com/golang/mock v1.5.0 h1:jlYHihg//f7RRwuPfptm04yp4s7O6Kw8EZiVYIGcH0g=
+github.com/golang/mock v1.5.0/go.mod h1:CWnOUgYIOo4TcNZ0wHX3YZCqsaM1I1Jvs6v3mP3KVu8=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.0/go.mod h1:Qd/q+1AKNOZr9uGQzbzCmRO6sUih6GTPZv6a1/R87v0=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
--- a/itests/batch_deal_test.go
+++ b/itests/batch_deal_test.go
@ -98,7 +98,7 @@ func TestBatchDealInput(t *testing.T) {

 			// Starts a deal and waits until it's published
 			runDealTillSeal := func(rseed int) {
-				res, _, err := kit.CreateImportFile(ctx, client, rseed, piece)
+				res, _, _, err := kit.CreateImportFile(ctx, client, rseed, piece)
 				require.NoError(t, err)

 				deal := dh.StartDeal(ctx, res.Root, false, dealStartEpoch)
--- a/itests/deals_test.go
+++ b/itests/deals_test.go
@ -4,7 +4,10 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"io/ioutil"
 	"math/rand"
+	"os"
+	"path/filepath"
 	"sync/atomic"
 	"testing"
 	"time"
@ -12,6 +15,7 @@ import (
 	"github.com/filecoin-project/go-fil-markets/storagemarket"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/market"
 	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/types"
@ -113,7 +117,7 @@ func TestPublishDealsBatching(t *testing.T) {

 	// Starts a deal and waits until it's published
 	runDealTillPublish := func(rseed int) {
-		res, _, err := kit.CreateImportFile(ctx, client, rseed, 0)
+		res, _, _, err := kit.CreateImportFile(ctx, client, rseed, 0)
 		require.NoError(t, err)

 		upds, err := client.ClientGetDealUpdates(ctx)
@ -308,6 +312,97 @@ func TestDealMining(t *testing.T) {
 	<-done
 }

+func TestOfflineDealFlow(t *testing.T) {
+	blocktime := 10 * time.Millisecond
+
+	// For these tests where the block time is artificially short, just use
+	// a deal start epoch that is guaranteed to be far enough in the future
+	// so that the deal starts sealing in time
+	startEpoch := abi.ChainEpoch(2 << 12)
+
+	runTest := func(t *testing.T, fastRet bool) {
+		ctx := context.Background()
+		fulls, miners := kit.MockMinerBuilder(t, kit.OneFull, kit.OneMiner)
+		client, miner := fulls[0].FullNode.(*impl.FullNodeAPI), miners[0]
+
+		kit.ConnectAndStartMining(t, blocktime, miner, client)
+
+		dh := kit.NewDealHarness(t, client, miner)
+
+		// Create a random file and import on the client.
+		res, path, data, err := kit.CreateImportFile(ctx, client, 1, 0)
+		require.NoError(t, err)
+
+		// Get the piece size and commP
+		fcid := res.Root
+		pieceInfo, err := client.ClientDealPieceCID(ctx, fcid)
+		require.NoError(t, err)
+		fmt.Println("FILE CID: ", fcid)
+
+		// Create a storage deal with the miner
+		maddr, err := miner.ActorAddress(ctx)
+		require.NoError(t, err)
+
+		addr, err := client.WalletDefaultAddress(ctx)
+		require.NoError(t, err)
+
+		// Manual storage deal (offline deal)
+		dataRef := &storagemarket.DataRef{
+			TransferType: storagemarket.TTManual,
+			Root:         fcid,
+			PieceCid:     &pieceInfo.PieceCID,
+			PieceSize:    pieceInfo.PieceSize.Unpadded(),
+		}
+
+		proposalCid, err := client.ClientStartDeal(ctx, &api.StartDealParams{
+			Data:              dataRef,
+			Wallet:            addr,
+			Miner:             maddr,
+			EpochPrice:        types.NewInt(1000000),
+			DealStartEpoch:    startEpoch,
+			MinBlocksDuration: uint64(build.MinDealDuration),
+			FastRetrieval:     fastRet,
+		})
+		require.NoError(t, err)
+
+		// Wait for the deal to reach StorageDealCheckForAcceptance on the client
+		cd, err := client.ClientGetDealInfo(ctx, *proposalCid)
+		require.NoError(t, err)
+		require.Eventually(t, func() bool {
+			cd, _ := client.ClientGetDealInfo(ctx, *proposalCid)
+			return cd.State == storagemarket.StorageDealCheckForAcceptance
+		}, 30*time.Second, 1*time.Second, "actual deal status is %s", storagemarket.DealStates[cd.State])
+
+		// Create a CAR file from the raw file
+		carFileDir, err := ioutil.TempDir(os.TempDir(), "test-make-deal-car")
+		require.NoError(t, err)
+		carFilePath := filepath.Join(carFileDir, "out.car")
+		err = client.ClientGenCar(ctx, api.FileRef{Path: path}, carFilePath)
+		require.NoError(t, err)
+
+		// Import the CAR file on the miner - this is the equivalent to
+		// transferring the file across the wire in a normal (non-offline) deal
+		err = miner.DealsImportData(ctx, *proposalCid, carFilePath)
+		require.NoError(t, err)
+
+		// Wait for the deal to be published
+		dh.WaitDealPublished(ctx, proposalCid)
+
+		t.Logf("deal published, retrieving")
+
+		// Retrieve the deal
+		dh.TestRetrieval(ctx, fcid, &pieceInfo.PieceCID, false, data)
+	}
+
+	t.Run("NormalRetrieval", func(t *testing.T) {
+		runTest(t, false)
+	})
+	t.Run("FastRetrieval", func(t *testing.T) {
+		runTest(t, true)
+	})
+
+}
+
 func runFullDealCycles(t *testing.T, n int, b kit.APIBuilder, blocktime time.Duration, carExport, fastRet bool, startEpoch abi.ChainEpoch) {
 	fulls, miners := b(t, kit.OneFull, kit.OneMiner)
 	client, miner := fulls[0].FullNode.(*impl.FullNodeAPI), miners[0]
--- a/itests/kit/client.go
+++ b/itests/kit/client.go
@ -43,7 +43,7 @@ func RunClientTest(t *testing.T, cmds []*lcli.Command, clientNode TestFullNode)

 	// Create a deal (non-interactive)
 	// client deal --start-epoch=<start epoch> <cid> <Miner addr> 1000000attofil <duration>
-	res, _, err := CreateImportFile(ctx, clientNode, 1, 0)
+	res, _, _, err := CreateImportFile(ctx, clientNode, 1, 0)

 	require.NoError(t, err)
 	startEpoch := fmt.Sprintf("--start-epoch=%d", 2<<12)
@ -60,7 +60,7 @@ func RunClientTest(t *testing.T, cmds []*lcli.Command, clientNode TestFullNode)
 	// <miner addr>
 	// "no" (verified Client)
 	// "yes" (confirm deal)
-	res, _, err = CreateImportFile(ctx, clientNode, 2, 0)
+	res, _, _, err = CreateImportFile(ctx, clientNode, 2, 0)
 	require.NoError(t, err)
 	dataCid2 := res.Root
 	duration = fmt.Sprintf("%d", build.MinDealDuration/builtin.EpochsInDay)
@ -111,17 +111,17 @@ func RunClientTest(t *testing.T, cmds []*lcli.Command, clientNode TestFullNode)
 	require.Regexp(t, regexp.MustCompile("Success"), out)
 }

-func CreateImportFile(ctx context.Context, client api.FullNode, rseed int, size int) (*api.ImportRes, []byte, error) {
-	data, path, err := createRandomFile(rseed, size)
+func CreateImportFile(ctx context.Context, client api.FullNode, rseed int, size int) (res *api.ImportRes, path string, data []byte, err error) {
+	data, path, err = createRandomFile(rseed, size)
 	if err != nil {
-		return nil, nil, err
+		return nil, "", nil, err
 	}

-	res, err := client.ClientImport(ctx, api.FileRef{Path: path})
+	res, err = client.ClientImport(ctx, api.FileRef{Path: path})
 	if err != nil {
-		return nil, nil, err
+		return nil, "", nil, err
 	}
-	return res, data, nil
+	return res, path, data, nil
 }

 func createRandomFile(rseed, size int) ([]byte, string, error) {
--- a/itests/kit/deals.go
+++ b/itests/kit/deals.go
@ -44,7 +44,7 @@ func NewDealHarness(t *testing.T, client api.FullNode, miner TestMiner) *DealHar
 }

 func (dh *DealHarness) MakeFullDeal(ctx context.Context, rseed int, carExport, fastRet bool, startEpoch abi.ChainEpoch) {
-	res, data, err := CreateImportFile(ctx, dh.client, rseed, 0)
+	res, _, data, err := CreateImportFile(ctx, dh.client, rseed, 0)
 	if err != nil {
 		dh.t.Fatal(err)
 	}
@ -182,7 +182,7 @@ func (dh *DealHarness) StartSealingWaiting(ctx context.Context) {
 	}
 }

-func (dh *DealHarness) TestRetrieval(ctx context.Context, fcid cid.Cid, piece *cid.Cid, carExport bool, data []byte) {
+func (dh *DealHarness) TestRetrieval(ctx context.Context, fcid cid.Cid, piece *cid.Cid, carExport bool, expect []byte) {
 	offers, err := dh.client.ClientFindData(ctx, fcid, piece)
 	if err != nil {
 		dh.t.Fatal(err)
@ -226,8 +226,8 @@ func (dh *DealHarness) TestRetrieval(ctx context.Context, fcid cid.Cid, piece *c
 		rdata = dh.ExtractCarData(ctx, rdata, rpath)
 	}

-	if !bytes.Equal(rdata, data) {
-		dh.t.Fatal("wrong data retrieved")
+	if !bytes.Equal(rdata, expect) {
+		dh.t.Fatal("wrong expect retrieved")
 	}
 }

@ -285,7 +285,7 @@ func ConnectAndStartMining(t *testing.T, blocktime time.Duration, miner TestMine

 	blockMiner := NewBlockMiner(t, miner)
 	blockMiner.MineBlocks(ctx, blocktime)
-
+	t.Cleanup(blockMiner.Stop)
 	return blockMiner
 }

--- a/itests/kit/node_builder.go
+++ b/itests/kit/node_builder.go
@ -525,9 +525,14 @@ func mockMinerBuilderOpts(t *testing.T, fullOpts []FullNodeOpts, storage []Stora
 		}

 		fulls[i].Stb = storageBuilder(fulls[i], mn, node.Options(
-			node.Override(new(sectorstorage.SectorManager), func() (sectorstorage.SectorManager, error) {
+			node.Override(new(*mock.SectorMgr), func() (*mock.SectorMgr, error) {
 				return mock.NewMockSectorMgr(nil), nil
 			}),
+
+			node.Override(new(sectorstorage.SectorManager), node.From(new(*mock.SectorMgr))),
+			node.Override(new(sectorstorage.Unsealer), node.From(new(*mock.SectorMgr))),
+			node.Override(new(sectorstorage.PieceProvider), node.From(new(*mock.SectorMgr))),
+
 			node.Override(new(ffiwrapper.Verifier), mock.MockVerifier),
 			node.Override(new(ffiwrapper.Prover), mock.MockProver),
 			node.Unset(new(*sectorstorage.Manager)),
@ -568,9 +573,14 @@ func mockMinerBuilderOpts(t *testing.T, fullOpts []FullNodeOpts, storage []Stora
 			opts = node.Options()
 		}
 		miners[i] = CreateTestStorageNode(ctx, t, genms[i].Worker, maddrs[i], pidKeys[i], f, mn, node.Options(
-			node.Override(new(sectorstorage.SectorManager), func() (sectorstorage.SectorManager, error) {
+			node.Override(new(*mock.SectorMgr), func() (*mock.SectorMgr, error) {
 				return mock.NewMockSectorMgr(sectors), nil
 			}),
+
+			node.Override(new(sectorstorage.SectorManager), node.From(new(*mock.SectorMgr))),
+			node.Override(new(sectorstorage.Unsealer), node.From(new(*mock.SectorMgr))),
+			node.Override(new(sectorstorage.PieceProvider), node.From(new(*mock.SectorMgr))),
+
 			node.Override(new(ffiwrapper.Verifier), mock.MockVerifier),
 			node.Override(new(ffiwrapper.Prover), mock.MockProver),
 			node.Unset(new(*sectorstorage.Manager)),
--- a/markets/retrievaladapter/provider.go
+++ b/markets/retrievaladapter/provider.go
@ -5,6 +5,7 @@ import (
 	"io"

 	"github.com/filecoin-project/lotus/api/v1api"
+	"golang.org/x/xerrors"

 	"github.com/ipfs/go-cid"
 	logging "github.com/ipfs/go-log/v2"
@ -25,15 +26,15 @@ import (
 var log = logging.Logger("retrievaladapter")

 type retrievalProviderNode struct {
-	miner  *storage.Miner
-	sealer sectorstorage.SectorManager
-	full   v1api.FullNode
+	miner *storage.Miner
+	pp    sectorstorage.PieceProvider
+	full  v1api.FullNode
 }

 // NewRetrievalProviderNode returns a new node adapter for a retrieval provider that talks to the
 // Lotus Node
-func NewRetrievalProviderNode(miner *storage.Miner, sealer sectorstorage.SectorManager, full v1api.FullNode) retrievalmarket.RetrievalProviderNode {
-	return &retrievalProviderNode{miner, sealer, full}
+func NewRetrievalProviderNode(miner *storage.Miner, pp sectorstorage.PieceProvider, full v1api.FullNode) retrievalmarket.RetrievalProviderNode {
+	return &retrievalProviderNode{miner, pp, full}
 }

 func (rpn *retrievalProviderNode) GetMinerWorkerAddress(ctx context.Context, miner address.Address, tok shared.TipSetToken) (address.Address, error) {
@ -67,24 +68,18 @@ func (rpn *retrievalProviderNode) UnsealSector(ctx context.Context, sectorID abi
 		ProofType: si.SectorType,
 	}

-	// Set up a pipe so that data can be written from the unsealing process
-	// into the reader returned by this function
-	r, w := io.Pipe()
-	go func() {
-		var commD cid.Cid
-		if si.CommD != nil {
-			commD = *si.CommD
-		}
+	var commD cid.Cid
+	if si.CommD != nil {
+		commD = *si.CommD
+	}

-		// Read the piece into the pipe's writer, unsealing the piece if necessary
-		log.Debugf("read piece in sector %d, offset %d, length %d from miner %d", sectorID, offset, length, mid)
-		err := rpn.sealer.ReadPiece(ctx, w, ref, storiface.UnpaddedByteIndex(offset), length, si.TicketValue, commD)
-		if err != nil {
-			log.Errorf("failed to unseal piece from sector %d: %s", sectorID, err)
-		}
-		// Close the reader with any error that was returned while reading the piece
-		_ = w.CloseWithError(err)
-	}()
+	// Get a reader for the piece, unsealing the piece if necessary
+	log.Debugf("read piece in sector %d, offset %d, length %d from miner %d", sectorID, offset, length, mid)
+	r, unsealed, err := rpn.pp.ReadPiece(ctx, ref, storiface.UnpaddedByteIndex(offset), length, si.TicketValue, commD)
+	if err != nil {
+		return nil, xerrors.Errorf("failed to unseal piece from sector %d: %w", sectorID, err)
+	}
+	_ = unsealed // todo: use

 	return r, nil
 }
--- a/node/builder.go
+++ b/node/builder.go
@ -375,9 +375,12 @@ var MinerNode = Options(
 	Override(new(*stores.Index), stores.NewIndex),
 	Override(new(stores.SectorIndex), From(new(*stores.Index))),
 	Override(new(stores.LocalStorage), From(new(repo.LockedRepo))),
+	Override(new(*stores.Local), modules.LocalStorage),
+	Override(new(*stores.Remote), modules.RemoteStorage),
 	Override(new(*sectorstorage.Manager), modules.SectorStorage),
 	Override(new(sectorstorage.SectorManager), From(new(*sectorstorage.Manager))),
 	Override(new(storiface.WorkerReturn), From(new(sectorstorage.SectorManager))),
+	Override(new(sectorstorage.Unsealer), From(new(*sectorstorage.Manager))),

 	// Sector storage: Proofs
 	Override(new(ffiwrapper.Verifier), ffiwrapper.ProofVerifier),
@ -405,6 +408,7 @@ var MinerNode = Options(
 	Override(new(*sectorblocks.SectorBlocks), sectorblocks.NewSectorBlocks),

 	// Markets (retrieval)
+	Override(new(sectorstorage.PieceProvider), sectorstorage.NewPieceProvider),
 	Override(new(retrievalmarket.RetrievalProvider), modules.RetrievalProvider),
 	Override(new(dtypes.RetrievalDealFilter), modules.RetrievalDealFilter(nil)),
 	Override(HandleRetrievalKey, modules.HandleRetrieval),
--- a/node/impl/remoteworker.go
+++ b/node/impl/remoteworker.go
@ -38,6 +38,16 @@ func connectRemoteWorker(ctx context.Context, fa api.Common, url string) (*remot
 		return nil, xerrors.Errorf("creating jsonrpc client: %w", err)
 	}

+	wver, err := wapi.Version(ctx)
+	if err != nil {
+		closer()
+		return nil, err
+	}
+
+	if !wver.EqMajorMinor(api.WorkerAPIVersion0) {
+		return nil, xerrors.Errorf("unsupported worker api version: %s (expected %s)", wver, api.WorkerAPIVersion0)
+	}
+
 	return &remoteWorker{wapi, closer}, nil
 }

--- a/node/modules/dtypes/miner.go
+++ b/node/modules/dtypes/miner.go
@ -74,10 +74,12 @@ type ConsiderUnverifiedStorageDealsConfigFunc func() (bool, error)
 // disable or enable unverified storage deal acceptance.
 type SetConsiderUnverifiedStorageDealsConfigFunc func(bool) error

-// SetSealingDelay sets how long a sector waits for more deals before sealing begins.
+// SetSealingConfigFunc is a function which is used to
+// sets the sealing config.
 type SetSealingConfigFunc func(sealiface.Config) error

-// GetSealingDelay returns how long a sector waits for more deals before sealing begins.
+// GetSealingConfigFunc is a function which is used to
+// get the sealing config.
 type GetSealingConfigFunc func() (sealiface.Config, error)

 // SetExpectedSealDurationFunc is a function which is used to set how long sealing is expected to take.
--- a/node/modules/storageminer.go
+++ b/node/modules/storageminer.go
@ -637,17 +637,15 @@ func RetrievalDealFilter(userFilter dtypes.RetrievalDealFilter) func(onlineOk dt
 // RetrievalProvider creates a new retrieval provider attached to the provider blockstore
 func RetrievalProvider(h host.Host,
 	miner *storage.Miner,
-	sealer sectorstorage.SectorManager,
 	full v1api.FullNode,
 	ds dtypes.MetadataDS,
 	pieceStore dtypes.ProviderPieceStore,
 	mds dtypes.StagingMultiDstore,
 	dt dtypes.ProviderDataTransfer,
-	onlineOk dtypes.ConsiderOnlineRetrievalDealsConfigFunc,
-	offlineOk dtypes.ConsiderOfflineRetrievalDealsConfigFunc,
+	pieceProvider sectorstorage.PieceProvider,
 	userFilter dtypes.RetrievalDealFilter,
 ) (retrievalmarket.RetrievalProvider, error) {
-	adapter := retrievaladapter.NewRetrievalProviderNode(miner, sealer, full)
+	adapter := retrievaladapter.NewRetrievalProviderNode(miner, pieceProvider, full)

 	maddr, err := minerAddrFromDS(ds)
 	if err != nil {
@ -663,13 +661,22 @@ func RetrievalProvider(h host.Host,
 var WorkerCallsPrefix = datastore.NewKey("/worker/calls")
 var ManagerWorkPrefix = datastore.NewKey("/stmgr/calls")

-func SectorStorage(mctx helpers.MetricsCtx, lc fx.Lifecycle, ls stores.LocalStorage, si stores.SectorIndex, sc sectorstorage.SealerConfig, urls sectorstorage.URLs, sa sectorstorage.StorageAuth, ds dtypes.MetadataDS) (*sectorstorage.Manager, error) {
+func LocalStorage(mctx helpers.MetricsCtx, lc fx.Lifecycle, ls stores.LocalStorage, si stores.SectorIndex, urls sectorstorage.URLs) (*stores.Local, error) {
+	ctx := helpers.LifecycleCtx(mctx, lc)
+	return stores.NewLocal(ctx, ls, si, urls)
+}
+
+func RemoteStorage(lstor *stores.Local, si stores.SectorIndex, sa sectorstorage.StorageAuth, sc sectorstorage.SealerConfig) *stores.Remote {
+	return stores.NewRemote(lstor, si, http.Header(sa), sc.ParallelFetchLimit, &stores.DefaultPartialFileHandler{})
+}
+
+func SectorStorage(mctx helpers.MetricsCtx, lc fx.Lifecycle, lstor *stores.Local, stor *stores.Remote, ls stores.LocalStorage, si stores.SectorIndex, sc sectorstorage.SealerConfig, ds dtypes.MetadataDS) (*sectorstorage.Manager, error) {
 	ctx := helpers.LifecycleCtx(mctx, lc)

 	wsts := statestore.New(namespace.Wrap(ds, WorkerCallsPrefix))
 	smsts := statestore.New(namespace.Wrap(ds, ManagerWorkPrefix))

-	sst, err := sectorstorage.New(ctx, ls, si, sc, urls, sa, wsts, smsts)
+	sst, err := sectorstorage.New(ctx, lstor, stor, ls, si, sc, wsts, smsts)
 	if err != nil {
 		return nil, err
 	}
--- a/snap/local/icon.svg
+++ b/snap/local/icon.svg
@ -0,0 +1 @@
+<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0" y="0" viewBox="0 0 127 127" xml:space="preserve" enable-background="new 0 0 127 127"><style type="text/css">.st0{fill:#00d2d6}.st1{fill:#fff}</style><g><path class="st0" d="M63.5,127C28.5,127.1-0.2,98.4,0,63.2C0.2,28.3,28.6-0.2,63.9,0c34.8,0.2,63.3,28.7,63.1,64 C126.7,98.7,98.5,127.1,63.5,127z M71.4,57.6c5.5,0.8,11,1.5,16.5,2.3c0.5-1.7,0.9-3.1,1.3-4.7c-5.7-0.8-11.2-1.7-17.1-2.5 c2-7,3.7-13.7,5.8-20.2c0.7-2.2,2.3-4.2,3.9-5.9c2.1-2.2,5-1.7,6.8,0.7c0.7,1,1.4,2.1,2.3,2.9c1.1,1.1,2.8,1.6,4,0.6 c0.8-0.7,0.7-2.4,0.8-3.6c0-0.5-0.6-1.1-1-1.6c-2-2.3-4.7-3.1-7.5-3.2c-6.3-0.3-10.9,3-14.5,7.8c-3.5,4.8-5.1,10.5-6.8,16.2 c-0.5,1.6-0.9,3.3-1.4,5.1c-6.2-0.9-12.1-1.7-18.2-2.6c-0.2,1.6-0.4,3.2-0.6,4.8c6,0.9,11.8,1.8,17.8,2.7c-0.8,3.4-1.5,6.5-2.3,9.7 c-5.8-0.8-11.4-1.6-17-2.4c-0.2,1.8-0.4,3.2-0.6,4.8c5.6,0.9,11,1.7,16.5,2.5c0,0.6,0.1,1,0,1.3c-1.7,7.4-3.4,14.8-5.3,22.2 c-0.9,3.5-2.4,6.9-5.3,9.3c-2.4,2-5,1.7-6.8-0.8c-0.8-1.1-1.5-2.5-2.6-3.3c-0.8-0.6-2.5-0.9-3.1-0.5c-0.9,0.7-1.5,2.2-1.4,3.3 c0.1,1,1,2.2,1.9,2.8c3,2.3,6.5,2.6,10,1.9c5.9-1.2,10.1-4.9,12.7-10.1c2-4.1,3.6-8.5,5-12.9c1.3-4,2.2-8,3.3-12.2 c5.8,0.8,11.5,1.7,17.3,2.5c0.5-1.7,0.9-3.2,1.4-4.8c-6.1-0.9-11.9-1.7-17.7-2.6C70.1,64,70.7,60.9,71.4,57.6z"/><path class="st1" d="M71.4,57.6c-0.7,3.3-1.3,6.4-2,9.8c5.9,0.9,11.7,1.7,17.7,2.6c-0.5,1.6-0.9,3.1-1.4,4.8 c-5.8-0.8-11.5-1.7-17.3-2.5c-1.1,4.2-2,8.3-3.3,12.2c-1.4,4.4-3,8.7-5,12.9c-2.6,5.2-6.8,8.9-12.7,10.1c-3.5,0.7-7,0.4-10-1.9 c-0.9-0.7-1.8-1.8-1.9-2.8c-0.1-1.1,0.5-2.7,1.4-3.3c0.6-0.5,2.3-0.1,3.1,0.5c1.1,0.8,1.8,2.1,2.6,3.3c1.8,2.5,4.4,2.9,6.8,0.8 c2.9-2.5,4.4-5.8,5.3-9.3c1.9-7.3,3.6-14.8,5.3-22.2c0.1-0.3,0-0.7,0-1.3c-5.4-0.8-10.8-1.7-16.5-2.5c0.2-1.6,0.4-3,0.6-4.8 c5.6,0.8,11.1,1.6,17,2.4c0.8-3.2,1.5-6.4,2.3-9.7c-6-0.9-11.7-1.8-17.8-2.7c0.2-1.6,0.4-3.2,0.6-4.8c6.1,0.9,12,1.7,18.2,2.6 c0.5-1.8,0.9-3.5,1.4-5.1c1.7-5.6,3.2-11.3,6.8-16.2c3.6-4.9,8.1-8.1,14.5-7.8c2.8,0.1,5.5,0.9,7.5,3.2c0.4,0.5,1,1.1,1,1.6 c-0.1,1.2,0,2.9-0.8,3.6c-1.1,1.1-2.8,0.5-4-0.6c-0.9-0.9-1.6-1.9-2.3-2.9c-1.8-2.4-4.7-2.9-6.8-0.7c-1.6,1.7-3.2,3.7-3.9,5.9 C75.7,39.4,74,46,72,53c5.9,0.9,11.4,1.7,17.1,2.5c-0.5,1.6-0.9,3.1-1.3,4.7C82.3,59.1,76.9,58.3,71.4,57.6z"/></g></svg>
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@ -1,28 +1,76 @@
-name: lotus
-base: core18
-version: '1.8.0'
+name: lotus-filecoin
+base: core20
+version: latest
 summary: filecoin daemon/client
+icon: snap/local/icon.svg
 description: |
  Filecoin is a peer-to-peer network that stores files on the internet
  with built-in economic incentives to ensure files are stored reliably over time
+
+  For documentation and additional information, please see the following resources
+
+  https://filecoin.io
+
+  https://fil.org
+
+  https://docs.filecoin.io
+
+  https://github.com/filecoin-project/lotus
+
 grade: devel
-confinement: devmode # use 'strict' once you have the right plugs and slots
+confinement: strict

 parts:
-  libs:
-    plugin: dump
+  lotus:
+    plugin: make
    source: ./
-    organize:
-      'lotus' : bin/
-      'lotus-*' : bin/
+    build-snaps:
+      - go
+      - rustup
+    build-packages:
+      - git
+      - jq
+      - libhwloc-dev
+      - ocl-icd-opencl-dev
+      - pkg-config
    stage-packages:
+      - libhwloc15
      - ocl-icd-libopencl1
-      - libhwloc1
-      - libgcc1
+    override-build: |
+      LDFLAGS="" make lotus lotus-miner lotus-worker
+      cp lotus lotus-miner lotus-worker $SNAPCRAFT_PART_INSTALL
+
 apps:
  lotus:
-    command: bin/lotus
+    command: lotus
+    plugs:
+      - network
+      - network-bind
+      - home
+    environment:
+      FIL_PROOFS_PARAMETER_CACHE: $SNAP_USER_COMMON/filecoin-proof-parameters
+      LOTUS_PATH: $SNAP_USER_COMMON/lotus
+      LOTUS_MINER_PATH: $SNAP_USER_COMMON/lotus-miner
+      LOTUS_WORKER_PATH: $SNAP_USER_COMMON/lotus-worker
  lotus-miner:
-    command: bin/lotus-miner
+    command: lotus-miner
+    plugs:
+      - network
+      - network-bind
+      - opengl
+    environment:
+      FIL_PROOFS_PARAMETER_CACHE: $SNAP_USER_COMMON/filecoin-proof-parameters
+      LOTUS_PATH: $SNAP_USER_COMMON/lotus
+      LOTUS_MINER_PATH: $SNAP_USER_COMMON/lotus-miner
+      LOTUS_WORKER_PATH: $SNAP_USER_COMMON/lotus-worker
  lotus-worker:
-    command: bin/lotus-worker
+    command: lotus-worker
+    plugs:
+      - network
+      - network-bind
+      - opengl
+    environment:
+      FIL_PROOFS_PARAMETER_CACHE: $SNAP_USER_COMMON/filecoin-proof-parameters
+      LOTUS_PATH: $SNAP_USER_COMMON/lotus
+      LOTUS_MINER_PATH: $SNAP_USER_COMMON/lotus-miner
+      LOTUS_WORKER_PATH: $SNAP_USER_COMMON/lotus-worker
--- a/testplans/Makefile
+++ b/testplans/Makefile
@ -6,18 +6,18 @@ download-proofs:
 	go run github.com/filecoin-project/go-paramfetch/paramfetch 2048 ./docker-images/proof-parameters.json

 build-images:
-	docker build -t "iptestground/oni-buildbase:v14-lotus" -f "docker-images/Dockerfile.oni-buildbase" "docker-images"
-	docker build -t "iptestground/oni-runtime:v9" -f "docker-images/Dockerfile.oni-runtime" "docker-images"
-	docker build -t "iptestground/oni-runtime:v9-debug" -f "docker-images/Dockerfile.oni-runtime-debug" "docker-images"
+	docker build -t "iptestground/oni-buildbase:v15-lotus" -f "docker-images/Dockerfile.oni-buildbase" "docker-images"
+	docker build -t "iptestground/oni-runtime:v10" -f "docker-images/Dockerfile.oni-runtime" "docker-images"
+	docker build -t "iptestground/oni-runtime:v10-debug" -f "docker-images/Dockerfile.oni-runtime-debug" "docker-images"

 push-images:
-	docker push iptestground/oni-buildbase:v14-lotus
-	docker push iptestground/oni-runtime:v9
-	docker push iptestground/oni-runtime:v9-debug
+	docker push iptestground/oni-buildbase:v15-lotus
+	docker push iptestground/oni-runtime:v10
+	docker push iptestground/oni-runtime:v10-debug

 pull-images:
-	docker pull iptestground/oni-buildbase:v14-lotus
-	docker pull iptestground/oni-runtime:v9
-	docker pull iptestground/oni-runtime:v9-debug
+	docker pull iptestground/oni-buildbase:v15-lotus
+	docker pull iptestground/oni-runtime:v10
+	docker pull iptestground/oni-runtime:v10-debug

 .PHONY: download-proofs build-images push-images pull-images
--- a/testplans/docker-images/Dockerfile.oni-buildbase
+++ b/testplans/docker-images/Dockerfile.oni-buildbase
@ -4,7 +4,7 @@ FROM golang:${GO_VERSION}-buster

 RUN apt-get update && apt-get install -y ca-certificates llvm clang mesa-opencl-icd ocl-icd-opencl-dev jq gcc git pkg-config bzr libhwloc-dev

-ARG FILECOIN_FFI_COMMIT=d82899449741ce190e950a3582ebe33806f018a9
+ARG FILECOIN_FFI_COMMIT=8b97bd8230b77bd32f4f27e4766a6d8a03b4e801
 ARG FFI_DIR=/extern/filecoin-ffi

 RUN mkdir -p ${FFI_DIR} \
--- a/testplans/docker-images/Dockerfile.oni-runtime-debug
+++ b/testplans/docker-images/Dockerfile.oni-runtime-debug
@ -12,7 +12,7 @@ RUN go get github.com/filecoin-project/go-paramfetch/paramfetch@master
 COPY /proof-parameters.json /
 RUN paramfetch 8388608 /proof-parameters.json

-ARG LOTUS_COMMIT=7e25a811c3d80ea3e007a54aa1da089985110c2c
+ARG LOTUS_COMMIT=b8deee048eaf850113e8626a73f64b17ba69a9f6

 ## for debug purposes
 RUN apt update && apt install -y mesa-opencl-icd ocl-icd-opencl-dev gcc git bzr jq pkg-config libhwloc-dev curl && git clone https://github.com/filecoin-project/lotus.git && cd lotus/ && git checkout ${LOTUS_COMMIT} && make clean && make all && make install
--- a/testplans/lotus-soup/init.go
+++ b/testplans/lotus-soup/init.go
@ -42,7 +42,7 @@ func init() {
 	// deadline when the challenge is available.
 	//
 	// This will auto-scale the proving period.
-	policy.SetWPoStChallengeWindow(abi.ChainEpoch(5))
+	// policy.SetWPoStChallengeWindow(abi.ChainEpoch(5)) // commented-out until we enable PoSt faults tests

 	// Number of epochs between publishing the precommit and when the challenge for interactive PoRep is drawn
 	// used to ensure it is not predictable by miner.
--- a/testplans/lotus-soup/manifest.toml
+++ b/testplans/lotus-soup/manifest.toml
@ -9,8 +9,8 @@ enabled = true

 [builders."docker:go"]
 enabled = true
-build_base_image = "iptestground/oni-buildbase:v14-lotus"
-runtime_image = "iptestground/oni-runtime:v9-debug"
+build_base_image = "iptestground/oni-buildbase:v15-lotus"
+runtime_image = "iptestground/oni-runtime:v10-debug"

 [runners."local:exec"]
 enabled = true
				`@ -0,0 +1 @@`
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