diff --git a/vfs/xts/math.go b/internal/util/math.go
similarity index 58%
rename from vfs/xts/math.go
rename to internal/util/math.go
index b6cf113c..ffbd0c2f 100644
--- a/vfs/xts/math.go
+++ b/internal/util/math.go
@@ -1,4 +1,4 @@
-package xts
+package util
 
 func abs(n int) int {
 	if n < 0 {
@@ -7,16 +7,16 @@ func abs(n int) int {
 	return n
 }
 
-func gcd(m, n int) int {
+func GCD(m, n int) int {
 	for n != 0 {
 		m, n = n, m%n
 	}
 	return abs(m)
 }
 
-func lcm(m, n int) int {
+func LCM(m, n int) int {
 	if n == 0 {
 		return 0
 	}
-	return abs(n) * (abs(m) / gcd(m, n))
+	return abs(n) * (abs(m) / GCD(m, n))
 }
diff --git a/vfs/xts/math_test.go b/internal/util/math_test.go
similarity index 91%
rename from vfs/xts/math_test.go
rename to internal/util/math_test.go
index 5502c2c3..f403490c 100644
--- a/vfs/xts/math_test.go
+++ b/internal/util/math_test.go
@@ -1,4 +1,4 @@
-package xts
+package util
 
 import (
 	"math"
@@ -46,7 +46,7 @@ func Test_gcd(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run("", func(t *testing.T) {
-			if got := gcd(tt.arg1, tt.arg2); got != tt.want {
+			if got := GCD(tt.arg1, tt.arg2); got != tt.want {
 				t.Errorf("gcd(%d, %d) = %d, want %d", tt.arg1, tt.arg2, got, tt.want)
 			}
 		})
@@ -74,7 +74,7 @@ func Test_lcm(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run("", func(t *testing.T) {
-			if got := lcm(tt.arg1, tt.arg2); got != tt.want {
+			if got := LCM(tt.arg1, tt.arg2); got != tt.want {
 				t.Errorf("lcm(%d, %d) = %d, want %d", tt.arg1, tt.arg2, got, tt.want)
 			}
 		})
diff --git a/vfs/adiantum/hbsh.go b/vfs/adiantum/hbsh.go
index b84de1b2..8fce7ee9 100644
--- a/vfs/adiantum/hbsh.go
+++ b/vfs/adiantum/hbsh.go
@@ -187,7 +187,7 @@ func (h *hbshFile) Truncate(size int64) error {
 }
 
 func (h *hbshFile) SectorSize() int {
-	return lcm(h.File.SectorSize(), blockSize)
+	return util.LCM(h.File.SectorSize(), blockSize)
 }
 
 func (h *hbshFile) DeviceCharacteristics() vfs.DeviceCharacteristic {
diff --git a/vfs/adiantum/math.go b/vfs/adiantum/math.go
deleted file mode 100644
index 17f7a291..00000000
--- a/vfs/adiantum/math.go
+++ /dev/null
@@ -1,22 +0,0 @@
-package adiantum
-
-func abs(n int) int {
-	if n < 0 {
-		return -n
-	}
-	return n
-}
-
-func gcd(m, n int) int {
-	for n != 0 {
-		m, n = n, m%n
-	}
-	return abs(m)
-}
-
-func lcm(m, n int) int {
-	if n == 0 {
-		return 0
-	}
-	return abs(n) * (abs(m) / gcd(m, n))
-}
diff --git a/vfs/adiantum/math_test.go b/vfs/adiantum/math_test.go
deleted file mode 100644
index 2e2398a7..00000000
--- a/vfs/adiantum/math_test.go
+++ /dev/null
@@ -1,82 +0,0 @@
-package adiantum
-
-import (
-	"math"
-	"testing"
-)
-
-func Test_abs(t *testing.T) {
-	tests := []struct {
-		arg  int
-		want int
-	}{
-		{0, 0},
-		{1, 1},
-		{-1, 1},
-		{math.MaxInt, math.MaxInt},
-		{math.MinInt, math.MinInt},
-	}
-	for _, tt := range tests {
-		t.Run("", func(t *testing.T) {
-			if got := abs(tt.arg); got != tt.want {
-				t.Errorf("abs(%d) = %d, want %d", tt.arg, got, tt.want)
-			}
-		})
-	}
-}
-
-func Test_gcd(t *testing.T) {
-	tests := []struct {
-		arg1 int
-		arg2 int
-		want int
-	}{
-		{0, 0, 0},
-		{0, 1, 1},
-		{1, 0, 1},
-		{1, 1, 1},
-		{2, 3, 1},
-		{42, 56, 14},
-		{48, -18, 6},
-		{1e9, 1e9, 1e9},
-		{1e9, -1e9, 1e9},
-		{-1e9, -1e9, 1e9},
-		{math.MaxInt, math.MaxInt, math.MaxInt},
-		{math.MinInt, math.MinInt, math.MinInt},
-	}
-	for _, tt := range tests {
-		t.Run("", func(t *testing.T) {
-			if got := gcd(tt.arg1, tt.arg2); got != tt.want {
-				t.Errorf("gcd(%d, %d) = %d, want %d", tt.arg1, tt.arg2, got, tt.want)
-			}
-		})
-	}
-}
-
-func Test_lcm(t *testing.T) {
-	tests := []struct {
-		arg1 int
-		arg2 int
-		want int
-	}{
-		{0, 0, 0},
-		{0, 1, 0},
-		{1, 0, 0},
-		{1, 1, 1},
-		{2, 3, 6},
-		{42, 56, 168},
-		{48, -18, 144},
-		{1e9, 1e9, 1e9},
-		{1e9, -1e9, 1e9},
-		{-1e9, -1e9, 1e9},
-		{math.MaxInt, math.MaxInt, math.MaxInt},
-		{math.MinInt, math.MinInt, math.MinInt},
-	}
-	for _, tt := range tests {
-		t.Run("", func(t *testing.T) {
-			if got := lcm(tt.arg1, tt.arg2); got != tt.want {
-				t.Errorf("lcm(%d, %d) = %d, want %d", tt.arg1, tt.arg2, got, tt.want)
-			}
-		})
-	}
-}
diff --git a/vfs/xts/xts.go b/vfs/xts/xts.go
index fcd1321a..1c86d898 100644
--- a/vfs/xts/xts.go
+++ b/vfs/xts/xts.go
@@ -183,7 +183,7 @@ func (x *xtsFile) Truncate(size int64) error {
 }
 
 func (x *xtsFile) SectorSize() int {
-	return lcm(x.File.SectorSize(), sectorSize)
+	return util.LCM(x.File.SectorSize(), sectorSize)
 }
 
 func (x *xtsFile) DeviceCharacteristics() vfs.DeviceCharacteristic {