Add HCS storage APIs

computestorage/attach.go

@@ -0,0 +1,38 @@
+package computestorage
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+)
+
+// AttachLayerStorageFilter sets up the layer storage filter on a writable
+// container layer.
+//
+// `layerPath` is a path to a directory the writable layer is mounted. If the
+// path does not end in a `\` the platform will append it automatically.
+//
+// `layerData` is the parent read-only layer data.
+func AttachLayerStorageFilter(ctx context.Context, layerPath string, layerData LayerData) (err error) {
+	title := "hcsshim.AttachLayerStorageFilter"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(
+		trace.StringAttribute("layerPath", layerPath),
+	)
+
+	bytes, err := json.Marshal(layerData)
+	if err != nil {
+		return err
+	}
+
+	err = hcsAttachLayerStorageFilter(layerPath, string(bytes))
+	if err != nil {
+		return fmt.Errorf("failed to attach layer storage filter: %s", err)
+	}
+	return nil
+}

computestorage/destroy.go

@@ -0,0 +1,26 @@
+package computestorage
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+)
+
+// DestroyLayer deletes a container layer.
+//
+// `layerPath` is a path to a directory containing the layer to export.
+func DestroyLayer(ctx context.Context, layerPath string) (err error) {
+	title := "hcsshim.DestroyLayer"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(trace.StringAttribute("layerPath", layerPath))
+
+	err = hcsDestroyLayer(layerPath)
+	if err != nil {
+		return fmt.Errorf("failed to destroy layer: %s", err)
+	}
+	return nil
+}

computestorage/detach.go

@@ -0,0 +1,26 @@
+package computestorage
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+)
+
+// DetachLayerStorageFilter detaches the layer storage filter on a writable container layer.
+//
+// `layerPath` is a path to a directory containing the layer to export.
+func DetachLayerStorageFilter(ctx context.Context, layerPath string) (err error) {
+	title := "hcsshim.DetachLayerStorageFilter"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(trace.StringAttribute("layerPath", layerPath))
+
+	err = hcsDetachLayerStorageFilter(layerPath)
+	if err != nil {
+		return fmt.Errorf("failed to detach layer storage filter: %s", err)
+	}
+	return nil
+}

computestorage/export.go

@@ -0,0 +1,46 @@
+package computestorage
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+)
+
+// ExportLayer exports a container layer.
+//
+// `layerPath` is a path to a directory containing the layer to export.
+//
+// `exportFolderPath` is a pre-existing folder to export the layer to.
+//
+// `layerData` is the parent layer data.
+//
+// `options` are the export options applied to the exported layer.
+func ExportLayer(ctx context.Context, layerPath, exportFolderPath string, layerData LayerData, options ExportLayerOptions) (err error) {
+	title := "hcsshim.ExportLayer"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(
+		trace.StringAttribute("layerPath", layerPath),
+		trace.StringAttribute("exportFolderPath", exportFolderPath),
+	)
+
+	ldbytes, err := json.Marshal(layerData)
+	if err != nil {
+		return err
+	}
+
+	obytes, err := json.Marshal(options)
+	if err != nil {
+		return err
+	}
+
+	err = hcsExportLayer(layerPath, exportFolderPath, string(ldbytes), string(obytes))
+	if err != nil {
+		return fmt.Errorf("failed to export layer: %s", err)
+	}
+	return nil
+}

computestorage/format.go

@@ -0,0 +1,26 @@
+package computestorage
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+	"golang.org/x/sys/windows"
+)
+
+// FormatWritableLayerVhd formats a virtual disk for use as a writable container layer.
+//
+// If the VHD is not mounted it will be temporarily mounted.
+func FormatWritableLayerVhd(ctx context.Context, vhdHandle windows.Handle) (err error) {
+	title := "hcsshim.FormatWritableLayerVhd"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+
+	err = hcsFormatWritableLayerVhd(vhdHandle)
+	if err != nil {
+		return fmt.Errorf("failed to format writable layer vhd: %s", err)
+	}
+	return nil
+}

computestorage/import.go

@@ -0,0 +1,41 @@
+package computestorage
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+)
+
+// ImportLayer imports a container layer.
+//
+// `layerPath` is a path to a directory to import the layer to. If the directory
+// does not exist it will be automatically created.
+//
+// `sourceFolderpath` is a pre-existing folder that contains the layer to
+// import.
+//
+// `layerData` is the parent layer data.
+func ImportLayer(ctx context.Context, layerPath, sourceFolderPath string, layerData LayerData) (err error) {
+	title := "hcsshim.ImportLayer"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(
+		trace.StringAttribute("layerPath", layerPath),
+		trace.StringAttribute("sourceFolderPath", sourceFolderPath),
+	)
+
+	bytes, err := json.Marshal(layerData)
+	if err != nil {
+		return err
+	}
+
+	err = hcsImportLayer(layerPath, sourceFolderPath, string(bytes))
+	if err != nil {
+		return fmt.Errorf("failed to import layer: %s", err)
+	}
+	return nil
+}

computestorage/initialize.go

@@ -0,0 +1,38 @@
+package computestorage
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+)
+
+// InitializeWritableLayer initializes a writable layer for a container.
+//
+// `layerPath` is a path to a directory the layer is mounted. If the
+// path does not end in a `\` the platform will append it automatically.
+//
+// `layerData` is the parent read-only layer data.
+func InitializeWritableLayer(ctx context.Context, layerPath string, layerData LayerData) (err error) {
+	title := "hcsshim.InitializeWritableLayer"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(
+		trace.StringAttribute("layerPath", layerPath),
+	)
+
+	bytes, err := json.Marshal(layerData)
+	if err != nil {
+		return err
+	}
+
+	// Options are not used in the platform as of RS5
+	err = hcsInitializeWritableLayer(layerPath, string(bytes), "")
+	if err != nil {
+		return fmt.Errorf("failed to intitialize container layer: %s", err)
+	}
+	return nil
+}

computestorage/mount.go

@@ -0,0 +1,27 @@
+package computestorage
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/interop"
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"go.opencensus.io/trace"
+	"golang.org/x/sys/windows"
+)
+
+// GetLayerVhdMountPath returns the volume path for a virtual disk of a writable container layer.
+func GetLayerVhdMountPath(ctx context.Context, vhdHandle windows.Handle) (path string, err error) {
+	title := "hcsshim.GetLayerVhdMountPath"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+
+	var mountPath *uint16
+	err = hcsGetLayerVhdMountPath(vhdHandle, &mountPath)
+	if err != nil {
+		return "", fmt.Errorf("failed to get vhd mount path: %s", err)
+	}
+	path = interop.ConvertAndFreeCoTaskMemString(mountPath)
+	return path, nil
+}

computestorage/setup.go

@@ -0,0 +1,75 @@
+package computestorage
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+
+	"github.com/Microsoft/hcsshim/internal/oc"
+	"github.com/Microsoft/hcsshim/osversion"
+	"go.opencensus.io/trace"
+	"golang.org/x/sys/windows"
+)
+
+// SetupBaseOSLayer sets up a layer that contains a base OS for a container.
+//
+// `layerPath` is a path to a directory containing the layer.
+//
+// `vhdHandle` is an empty file handle of `options.Type == OsLayerTypeContainer`
+// or else it is a file handle to the 'SystemTemplateBase.vhdx' if `options.Type
+// == OsLayerTypeVm`.
+//
+// `options` are the options applied while processing the layer.
+func SetupBaseOSLayer(ctx context.Context, layerPath string, vhdHandle windows.Handle, options OsLayerOptions) (err error) {
+	title := "hcsshim.SetupBaseOSLayer"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(
+		trace.StringAttribute("layerPath", layerPath),
+	)
+
+	bytes, err := json.Marshal(options)
+	if err != nil {
+		return err
+	}
+
+	err = hcsSetupBaseOSLayer(layerPath, vhdHandle, string(bytes))
+	if err != nil {
+		return fmt.Errorf("failed to setup base OS layer: %s", err)
+	}
+	return nil
+}
+
+// SetupBaseOSVolume sets up a volume that contains a base OS for a container.
+//
+// `layerPath` is a path to a directory containing the layer.
+//
+// `volumePath` is the path to the volume to be used for setup.
+//
+// `options` are the options applied while processing the layer.
+func SetupBaseOSVolume(ctx context.Context, layerPath, volumePath string, options OsLayerOptions) (err error) {
+	if osversion.Get().Build < 19645 {
+		return errors.New("SetupBaseOSVolume is not present on builds older than 19645")
+	}
+	title := "hcsshim.SetupBaseOSVolume"
+	ctx, span := trace.StartSpan(ctx, title)
+	defer span.End()
+	defer func() { oc.SetSpanStatus(span, err) }()
+	span.AddAttributes(
+		trace.StringAttribute("layerPath", layerPath),
+		trace.StringAttribute("volumePath", volumePath),
+	)
+
+	bytes, err := json.Marshal(options)
+	if err != nil {
+		return err
+	}
+
+	err = hcsSetupBaseOSVolume(layerPath, volumePath, string(bytes))
+	if err != nil {
+		return fmt.Errorf("failed to setup base OS layer: %s", err)
+	}
+	return nil
+}