multi: thread context through FetchPayment

diff --git a/payments/db/interface.go b/payments/db/interface.go
index c6f1bf3..5368d53 100644
--- a/payments/db/interface.go
+++ b/payments/db/interface.go
@@ -21,7 +21,8 @@ type PaymentReader interface {
 
 	// FetchPayment fetches the payment corresponding to the given payment
 	// hash.
-	FetchPayment(paymentHash lntypes.Hash) (*MPPayment, error)
+	FetchPayment(ctx context.Context,
+		paymentHash lntypes.Hash) (*MPPayment, error)
 
 	// FetchInFlightPayments returns all payments with status InFlight.
 	FetchInFlightPayments() ([]*MPPayment, error)
diff --git a/payments/db/kv_store.go b/payments/db/kv_store.go
index d3d347a..86b37ed 100644
--- a/payments/db/kv_store.go
+++ b/payments/db/kv_store.go
@@ -585,8 +585,8 @@ func (p *KVStore) Fail(paymentHash lntypes.Hash,
 }
 
 // FetchPayment returns information about a payment from the database.
-func (p *KVStore) FetchPayment(paymentHash lntypes.Hash) (
-	*MPPayment, error) {
+func (p *KVStore) FetchPayment(_ context.Context,
+	paymentHash lntypes.Hash) (*MPPayment, error) {
 
 	var payment *MPPayment
 	err := kvdb.View(p.db, func(tx kvdb.RTx) error {
diff --git a/payments/db/kv_store_test.go b/payments/db/kv_store_test.go
index cf5a9a9..910c181 100644
--- a/payments/db/kv_store_test.go
+++ b/payments/db/kv_store_test.go
@@ -409,6 +409,8 @@ func deletePayment(t *testing.T, db kvdb.Backend, paymentHash lntypes.Hash,
 func TestFetchPaymentWithSequenceNumber(t *testing.T) {
 	paymentDB := NewKVTestDB(t)
 
+	ctx := t.Context()
+
 	// Generate a test payment which does not have duplicates.
 	noDuplicates, _, err := genInfo(t)
 	require.NoError(t, err)
@@ -421,7 +423,7 @@ func TestFetchPaymentWithSequenceNumber(t *testing.T) {
 
 	// Fetch the payment so we can get its sequence nr.
 	noDuplicatesPayment, err := paymentDB.FetchPayment(
-		noDuplicates.PaymentIdentifier,
+		ctx, noDuplicates.PaymentIdentifier,
 	)
 	require.NoError(t, err)
 
@@ -437,7 +439,7 @@ func TestFetchPaymentWithSequenceNumber(t *testing.T) {
 
 	// Fetch the payment so we can get its sequence nr.
 	hasDuplicatesPayment, err := paymentDB.FetchPayment(
-		hasDuplicates.PaymentIdentifier,
+		ctx, hasDuplicates.PaymentIdentifier,
 	)
 	require.NoError(t, err)
 
@@ -749,7 +751,7 @@ func TestKVStoreQueryPaymentsDuplicates(t *testing.T) {
 				// Immediately delete the payment with index 2.
 				if i == 1 {
 					pmt, err := paymentDB.FetchPayment(
-						info.PaymentIdentifier,
+						ctx, info.PaymentIdentifier,
 					)
 					require.NoError(t, err)
 
@@ -766,7 +768,7 @@ func TestKVStoreQueryPaymentsDuplicates(t *testing.T) {
 				// duplicate payments will always be succeeded.
 				if i == (nonDuplicatePayments - 1) {
 					pmt, err := paymentDB.FetchPayment(
-						info.PaymentIdentifier,
+						ctx, info.PaymentIdentifier,
 					)
 					require.NoError(t, err)
 
diff --git a/payments/db/payment_test.go b/payments/db/payment_test.go
index 4a9a69b..8954f8a 100644
--- a/payments/db/payment_test.go
+++ b/payments/db/payment_test.go
@@ -235,7 +235,9 @@ func assertPaymentInfo(t *testing.T, p DB, hash lntypes.Hash,
 
 	t.Helper()
 
-	payment, err := p.FetchPayment(hash)
+	ctx := t.Context()
+
+	payment, err := p.FetchPayment(ctx, hash)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -303,7 +305,9 @@ func assertDBPaymentstatus(t *testing.T, p DB, hash lntypes.Hash,
 
 	t.Helper()
 
-	payment, err := p.FetchPayment(hash)
+	ctx := t.Context()
+
+	payment, err := p.FetchPayment(ctx, hash)
 	if errors.Is(err, ErrPaymentNotInitiated) {
 		return
 	}
@@ -1796,6 +1800,8 @@ func TestSwitchDoubleSend(t *testing.T) {
 func TestSwitchFail(t *testing.T) {
 	t.Parallel()
 
+	ctx := t.Context()
+
 	paymentDB, harness := NewTestDB(t)
 
 	preimg, err := genPreimage(t)
@@ -1834,7 +1840,7 @@ func TestSwitchFail(t *testing.T) {
 
 	// Lookup the payment so we can get its old sequence number before it is
 	// overwritten.
-	payment, err := paymentDB.FetchPayment(info.PaymentIdentifier)
+	payment, err := paymentDB.FetchPayment(ctx, info.PaymentIdentifier)
 	require.NoError(t, err)
 
 	// Sends the htlc again, which should succeed since the prior payment
@@ -2609,7 +2615,7 @@ func TestQueryPayments(t *testing.T) {
 			// Now delete the payment at index 1 (the second
 			// payment).
 			pmt, err := paymentDB.FetchPayment(
-				paymentInfos[1].PaymentIdentifier,
+				ctx, paymentInfos[1].PaymentIdentifier,
 			)
 			require.NoError(t, err)
 
@@ -2621,7 +2627,7 @@ func TestQueryPayments(t *testing.T) {
 
 			// Verify the payment is deleted.
 			_, err = paymentDB.FetchPayment(
-				paymentInfos[1].PaymentIdentifier,
+				ctx, paymentInfos[1].PaymentIdentifier,
 			)
 			require.ErrorIs(
 				t, err, ErrPaymentNotInitiated,
diff --git a/payments/db/sql_store.go b/payments/db/sql_store.go
index ef0d96c..9423364 100644
--- a/payments/db/sql_store.go
+++ b/payments/db/sql_store.go
@@ -922,8 +922,8 @@ func fetchPaymentByHash(ctx context.Context, db SQLQueries,
 // Returns ErrPaymentNotInitiated if no payment with the given hash exists.
 //
 // This is part of the DB interface.
-func (s *SQLStore) FetchPayment(paymentHash lntypes.Hash) (*MPPayment, error) {
-	ctx := context.TODO()
+func (s *SQLStore) FetchPayment(ctx context.Context,
+	paymentHash lntypes.Hash) (*MPPayment, error) {
 
 	var mpPayment *MPPayment
 
diff --git a/payments/db/test_kvdb.go b/payments/db/test_kvdb.go
index ed1710b..c2de0b4 100644
--- a/payments/db/test_kvdb.go
+++ b/payments/db/test_kvdb.go
@@ -57,9 +57,11 @@ func (h *kvTestHarness) AssertPaymentIndex(t *testing.T,
 
 	t.Helper()
 
+	ctx := t.Context()
+
 	// Lookup the payment so that we have its sequence number and check
 	// that it has correctly been indexed in the payment indexes bucket.
-	pmt, err := h.db.FetchPayment(expectedHash)
+	pmt, err := h.db.FetchPayment(ctx, expectedHash)
 	require.NoError(t, err)
 
 	hash, err := h.fetchPaymentIndexEntry(t, pmt.SequenceNum)
diff --git a/routing/control_tower.go b/routing/control_tower.go
index 2b9e7dd..3102894 100644
--- a/routing/control_tower.go
+++ b/routing/control_tower.go
@@ -1,6 +1,7 @@
 package routing
 
 import (
+	"context"
 	"sync"
 
 	"github.com/lightningnetwork/lnd/lntypes"
@@ -52,7 +53,8 @@ type ControlTower interface {
 
 	// FetchPayment fetches the payment corresponding to the given payment
 	// hash.
-	FetchPayment(paymentHash lntypes.Hash) (paymentsdb.DBMPPayment, error)
+	FetchPayment(ctx context.Context,
+		paymentHash lntypes.Hash) (paymentsdb.DBMPPayment, error)
 
 	// FailPayment transitions a payment into the Failed state, and records
 	// the ultimate reason the payment failed. Note that this should only
@@ -164,6 +166,8 @@ func NewControlTower(db paymentsdb.DB) ControlTower {
 func (p *controlTower) InitPayment(paymentHash lntypes.Hash,
 	info *paymentsdb.PaymentCreationInfo) error {
 
+	ctx := context.TODO()
+
 	err := p.db.InitPayment(paymentHash, info)
 	if err != nil {
 		return err
@@ -174,7 +178,7 @@ func (p *controlTower) InitPayment(paymentHash lntypes.Hash,
 	p.paymentsMtx.Lock(paymentHash)
 	defer p.paymentsMtx.Unlock(paymentHash)
 
-	payment, err := p.db.FetchPayment(paymentHash)
+	payment, err := p.db.FetchPayment(ctx, paymentHash)
 	if err != nil {
 		return err
 	}
@@ -250,10 +254,11 @@ func (p *controlTower) FailAttempt(paymentHash lntypes.Hash,
 }
 
 // FetchPayment fetches the payment corresponding to the given payment hash.
-func (p *controlTower) FetchPayment(paymentHash lntypes.Hash) (
+func (p *controlTower) FetchPayment(ctx context.Context,
+	paymentHash lntypes.Hash) (
 	paymentsdb.DBMPPayment, error) {
 
-	return p.db.FetchPayment(paymentHash)
+	return p.db.FetchPayment(ctx, paymentHash)
 }
 
 // FailPayment transitions a payment into the Failed state, and records the
@@ -293,12 +298,14 @@ func (p *controlTower) FetchInFlightPayments() ([]*paymentsdb.MPPayment,
 func (p *controlTower) SubscribePayment(paymentHash lntypes.Hash) (
 	ControlTowerSubscriber, error) {
 
+	ctx := context.TODO()
+
 	// Take lock before querying the db to prevent missing or duplicating an
 	// update.
 	p.paymentsMtx.Lock(paymentHash)
 	defer p.paymentsMtx.Unlock(paymentHash)
 
-	payment, err := p.db.FetchPayment(paymentHash)
+	payment, err := p.db.FetchPayment(ctx, paymentHash)
 	if err != nil {
 		return nil, err
 	}
diff --git a/routing/mock_test.go b/routing/mock_test.go
index 19a76ee..556601e 100644
--- a/routing/mock_test.go
+++ b/routing/mock_test.go
@@ -1,6 +1,7 @@
 package routing
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"sync"
@@ -509,8 +510,8 @@ func (m *mockControlTowerOld) FailPayment(phash lntypes.Hash,
 	return nil
 }
 
-func (m *mockControlTowerOld) FetchPayment(phash lntypes.Hash) (
-	paymentsdb.DBMPPayment, error) {
+func (m *mockControlTowerOld) FetchPayment(_ context.Context,
+	phash lntypes.Hash) (paymentsdb.DBMPPayment, error) {
 
 	m.Lock()
 	defer m.Unlock()
@@ -786,8 +787,8 @@ func (m *mockControlTower) FailPayment(phash lntypes.Hash,
 	return args.Error(0)
 }
 
-func (m *mockControlTower) FetchPayment(phash lntypes.Hash) (
-	paymentsdb.DBMPPayment, error) {
+func (m *mockControlTower) FetchPayment(_ context.Context,
+	phash lntypes.Hash) (paymentsdb.DBMPPayment, error) {
 
 	args := m.Called(phash)
 
diff --git a/routing/payment_lifecycle.go b/routing/payment_lifecycle.go
index 8353cba..4eb78c8 100644
--- a/routing/payment_lifecycle.go
+++ b/routing/payment_lifecycle.go
@@ -1114,7 +1114,9 @@ func (p *paymentLifecycle) patchLegacyPaymentHash(
 func (p *paymentLifecycle) reloadInflightAttempts() (paymentsdb.DBMPPayment,
 	error) {
 
-	payment, err := p.router.cfg.Control.FetchPayment(p.identifier)
+	ctx := context.TODO()
+
+	payment, err := p.router.cfg.Control.FetchPayment(ctx, p.identifier)
 	if err != nil {
 		return nil, err
 	}
@@ -1139,8 +1141,10 @@ func (p *paymentLifecycle) reloadInflightAttempts() (paymentsdb.DBMPPayment,
 func (p *paymentLifecycle) reloadPayment() (paymentsdb.DBMPPayment,
 	*paymentsdb.MPPaymentState, error) {
 
+	ctx := context.TODO()
+
 	// Read the db to get the latest state of the payment.
-	payment, err := p.router.cfg.Control.FetchPayment(p.identifier)
+	payment, err := p.router.cfg.Control.FetchPayment(ctx, p.identifier)
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/routing/router.go b/routing/router.go
index 19df5b9..8aa5acf 100644
--- a/routing/router.go
+++ b/routing/router.go
@@ -1064,13 +1064,15 @@ func (r *ChannelRouter) sendToRoute(htlcHash lntypes.Hash, rt *route.Route,
 	firstHopCustomRecords lnwire.CustomRecords) (*paymentsdb.HTLCAttempt,
 	error) {
 
+	ctx := context.TODO()
+
 	// Helper function to fail a payment. It makes sure the payment is only
 	// failed once so that the failure reason is not overwritten.
 	failPayment := func(paymentIdentifier lntypes.Hash,
 		reason paymentsdb.FailureReason) error {
 
 		payment, fetchErr := r.cfg.Control.FetchPayment(
-			paymentIdentifier,
+			ctx, paymentIdentifier,
 		)
 		if fetchErr != nil {
 			return fetchErr
diff --git a/routing/router_test.go b/routing/router_test.go
index 115c02c..7339432 100644
--- a/routing/router_test.go
+++ b/routing/router_test.go
@@ -1097,7 +1097,9 @@ func TestSendPaymentErrorPathPruning(t *testing.T) {
 	require.Equal(t, paymentsdb.FailureReasonNoRoute, err)
 
 	// Inspect the two attempts that were made before the payment failed.
-	p, err := ctx.router.cfg.Control.FetchPayment(*payment.paymentHash)
+	p, err := ctx.router.cfg.Control.FetchPayment(
+		t.Context(), *payment.paymentHash,
+	)
 	require.NoError(t, err)
 
 	htlcs := p.GetHTLCs()