cmd/earlyinit: load device drivers

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/earlyinit/main.go

@@ -242,5 +242,6 @@ func main() {
 		[]byte("/system/lib/firmware"),
 		0,
 	))
+	go dispatchModprobe(ctx, s)
 
 }

cmd/earlyinit/modprobe.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"os/exec"
+	"strings"
+
+	"hakurei.app/internal/kobject"
+	"hakurei.app/internal/report"
+	"hakurei.app/internal/uevent"
+)
+
+// ModprobeError describes an unsuccessful modprobe invocation.
+type ModprobeError struct {
+	ModAlias string `json:"modalias"`
+	Stdout   string `json:"stdout"`
+	Stderr   string `json:"stderr"`
+	ExitCode int    `json:"exit_code"`
+}
+
+var _ report.RepresentableError = ModprobeError{}
+
+func (ModprobeError) Representable() {}
+func (e ModprobeError) Error() string {
+	return fmt.Sprintf(
+		"modprobe exit status %d: %s",
+		e.ExitCode, strings.TrimSpace(e.Stderr),
+	)
+}
+
+// dispatchModprobe invokes modprobe for [uevent.KOBJ_ADD] events raising new
+// MODALIAS strings.
+func dispatchModprobe(
+	ctx context.Context,
+	s *kobject.State,
+) {
+	aliases := make(chan string, 1<<8)
+	go func() {
+		defer close(aliases)
+		s.Range(ctx, func(o *kobject.Object, act uevent.KobjectAction) bool {
+			if act == uevent.KOBJ_ADD && o.Driver == "" && o.ModAlias != "" {
+				aliases <- o.ModAlias
+			}
+			return true
+		})
+	}()
+
+	for alias := range aliases {
+		stdout, err := exec.Command("/system/sbin/modprobe", alias).Output()
+		if err == nil {
+			if len(stdout) > 0 {
+				log.Println(string(stdout))
+			}
+			continue
+		}
+
+		var exitError *exec.ExitError
+		if !errors.As(err, &exitError) || exitError == nil {
+			r.Dispatch(report.Degraded, "invoke modprobe", err)
+			continue
+		}
+
+		r.Dispatch(report.Trivial, "load device driver", ModprobeError{
+			ModAlias: alias,
+			Stdout:   string(stdout),
+			Stderr:   string(exitError.Stderr),
+			ExitCode: exitError.ExitCode(),
+		})
+	}
+}