Revert "Update runc to 1.0.0"

vendor/github.com/opencontainers/runc/libcontainer/cgroups/fs2/io.go

@@ -4,95 +4,60 @@ package fs2
 
 import (
 	"bufio"
-	"bytes"
-	"fmt"
 	"os"
 	"strconv"
 	"strings"
 
-	"github.com/sirupsen/logrus"
-
 	"github.com/opencontainers/runc/libcontainer/cgroups"
+	"github.com/opencontainers/runc/libcontainer/cgroups/fscommon"
 	"github.com/opencontainers/runc/libcontainer/configs"
 )
 
 func isIoSet(r *configs.Resources) bool {
 	return r.BlkioWeight != 0 ||
-		len(r.BlkioWeightDevice) > 0 ||
 		len(r.BlkioThrottleReadBpsDevice) > 0 ||
 		len(r.BlkioThrottleWriteBpsDevice) > 0 ||
 		len(r.BlkioThrottleReadIOPSDevice) > 0 ||
 		len(r.BlkioThrottleWriteIOPSDevice) > 0
 }
 
-// bfqDeviceWeightSupported checks for per-device BFQ weight support (added
-// in kernel v5.4, commit 795fe54c2a8) by reading from "io.bfq.weight".
-func bfqDeviceWeightSupported(bfq *os.File) bool {
-	if bfq == nil {
-		return false
-	}
-	_, _ = bfq.Seek(0, 0)
-	buf := make([]byte, 32)
-	_, _ = bfq.Read(buf)
-	// If only a single number (default weight) if read back, we have older kernel.
-	_, err := strconv.ParseInt(string(bytes.TrimSpace(buf)), 10, 64)
-	return err != nil
-}
-
 func setIo(dirPath string, r *configs.Resources) error {
 	if !isIoSet(r) {
 		return nil
 	}
 
-	// If BFQ IO scheduler is available, use it.
-	var bfq *os.File
-	if r.BlkioWeight != 0 || len(r.BlkioWeightDevice) > 0 {
-		var err error
-		bfq, err = cgroups.OpenFile(dirPath, "io.bfq.weight", os.O_RDWR)
-		if err == nil {
-			defer bfq.Close()
-		} else if !os.IsNotExist(err) {
-			return err
-		}
-	}
-
 	if r.BlkioWeight != 0 {
-		if bfq != nil { // Use BFQ.
-			if _, err := bfq.WriteString(strconv.FormatUint(uint64(r.BlkioWeight), 10)); err != nil {
+		filename := "io.bfq.weight"
+		if err := fscommon.WriteFile(dirPath, filename,
+			strconv.FormatUint(uint64(r.BlkioWeight), 10)); err != nil {
+			// if io.bfq.weight does not exist, then bfq module is not loaded.
+			// Fallback to use io.weight with a conversion scheme
+			if !os.IsNotExist(err) {
 				return err
 			}
-		} else {
-			// Fallback to io.weight with a conversion scheme.
 			v := cgroups.ConvertBlkIOToIOWeightValue(r.BlkioWeight)
-			if err := cgroups.WriteFile(dirPath, "io.weight", strconv.FormatUint(v, 10)); err != nil {
+			if err := fscommon.WriteFile(dirPath, "io.weight", strconv.FormatUint(v, 10)); err != nil {
 				return err
 			}
 		}
 	}
-	if bfqDeviceWeightSupported(bfq) {
-		for _, wd := range r.BlkioWeightDevice {
-			if _, err := bfq.WriteString(wd.WeightString() + "\n"); err != nil {
-				return fmt.Errorf("setting device weight %q: %w", wd.WeightString(), err)
-			}
-		}
-	}
 	for _, td := range r.BlkioThrottleReadBpsDevice {
-		if err := cgroups.WriteFile(dirPath, "io.max", td.StringName("rbps")); err != nil {
+		if err := fscommon.WriteFile(dirPath, "io.max", td.StringName("rbps")); err != nil {
 			return err
 		}
 	}
 	for _, td := range r.BlkioThrottleWriteBpsDevice {
-		if err := cgroups.WriteFile(dirPath, "io.max", td.StringName("wbps")); err != nil {
+		if err := fscommon.WriteFile(dirPath, "io.max", td.StringName("wbps")); err != nil {
 			return err
 		}
 	}
 	for _, td := range r.BlkioThrottleReadIOPSDevice {
-		if err := cgroups.WriteFile(dirPath, "io.max", td.StringName("riops")); err != nil {
+		if err := fscommon.WriteFile(dirPath, "io.max", td.StringName("riops")); err != nil {
 			return err
 		}
 	}
 	for _, td := range r.BlkioThrottleWriteIOPSDevice {
-		if err := cgroups.WriteFile(dirPath, "io.max", td.StringName("wiops")); err != nil {
+		if err := fscommon.WriteFile(dirPath, "io.max", td.StringName("wiops")); err != nil {
 			return err
 		}
 	}
@@ -102,7 +67,7 @@ func setIo(dirPath string, r *configs.Resources) error {
 
 func readCgroup2MapFile(dirPath string, name string) (map[string][]string, error) {
 	ret := map[string][]string{}
-	f, err := cgroups.OpenFile(dirPath, name, os.O_RDONLY)
+	f, err := fscommon.OpenFile(dirPath, name, os.O_RDONLY)
 	if err != nil {
 		return nil, err
 	}
@@ -123,22 +88,22 @@ func readCgroup2MapFile(dirPath string, name string) (map[string][]string, error
 }
 
 func statIo(dirPath string, stats *cgroups.Stats) error {
+	// more details on the io.stat file format: https://www.kernel.org/doc/Documentation/cgroup-v2.txt
+	var ioServiceBytesRecursive []cgroups.BlkioStatEntry
 	values, err := readCgroup2MapFile(dirPath, "io.stat")
 	if err != nil {
 		return err
 	}
-	// more details on the io.stat file format: https://www.kernel.org/doc/Documentation/cgroup-v2.txt
-	var parsedStats cgroups.BlkioStats
 	for k, v := range values {
 		d := strings.Split(k, ":")
 		if len(d) != 2 {
 			continue
 		}
-		major, err := strconv.ParseUint(d[0], 10, 64)
+		major, err := strconv.ParseUint(d[0], 10, 0)
 		if err != nil {
 			return err
 		}
-		minor, err := strconv.ParseUint(d[1], 10, 64)
+		minor, err := strconv.ParseUint(d[1], 10, 0)
 		if err != nil {
 			return err
 		}
@@ -150,32 +115,15 @@ func statIo(dirPath string, stats *cgroups.Stats) error {
 			}
 			op := d[0]
 
-			// Map to the cgroupv1 naming and layout (in separate tables).
-			var targetTable *[]cgroups.BlkioStatEntry
+			// Accommodate the cgroup v1 naming
 			switch op {
-			// Equivalent to cgroupv1's blkio.io_service_bytes.
 			case "rbytes":
-				op = "Read"
-				targetTable = &parsedStats.IoServiceBytesRecursive
+				op = "read"
 			case "wbytes":
-				op = "Write"
-				targetTable = &parsedStats.IoServiceBytesRecursive
-			// Equivalent to cgroupv1's blkio.io_serviced.
-			case "rios":
-				op = "Read"
-				targetTable = &parsedStats.IoServicedRecursive
-			case "wios":
-				op = "Write"
-				targetTable = &parsedStats.IoServicedRecursive
-			default:
-				// Skip over entries we cannot map to cgroupv1 stats for now.
-				// In the future we should expand the stats struct to include
-				// them.
-				logrus.Debugf("cgroupv2 io stats: skipping over unmappable %s entry", item)
-				continue
+				op = "write"
 			}
 
-			value, err := strconv.ParseUint(d[1], 10, 64)
+			value, err := strconv.ParseUint(d[1], 10, 0)
 			if err != nil {
 				return err
 			}
@@ -186,9 +134,9 @@ func statIo(dirPath string, stats *cgroups.Stats) error {
 				Minor: minor,
 				Value: value,
 			}
-			*targetTable = append(*targetTable, entry)
+			ioServiceBytesRecursive = append(ioServiceBytesRecursive, entry)
 		}
 	}
-	stats.BlkioStats = parsedStats
+	stats.BlkioStats = cgroups.BlkioStats{IoServiceBytesRecursive: ioServiceBytesRecursive}
 	return nil
 }