d7: add POSIX mq syscall kind/classification and coverage

2 files changed, 145 insertions, 0 deletions

diff --git a/cmd/ioworkload/scenario_mq.go b/cmd/ioworkload/scenario_mq.go
new file mode 100644
index 0000000..8b627a7
--- /dev/null
+++ b/cmd/ioworkload/scenario_mq.go
@@ -0,0 +1,144 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"syscall"
+	"time"
+	"unsafe"
+)
+
+const (
+	mqPayload = "ior-mq-payload"
+)
+
+type mqAttr struct {
+	Flags   int64
+	Maxmsg  int64
+	Msgsize int64
+	Curmsgs int64
+	Pad     [4]int64
+}
+
+func mqPosixBasic() error {
+	name := fmt.Sprintf("/ior-mq-%d-%d", os.Getpid(), time.Now().UnixNano())
+	attr := mqAttr{Maxmsg: 8, Msgsize: 128}
+	mqd, err := mqOpen(name, syscall.O_CREAT|syscall.O_EXCL|syscall.O_RDWR, 0o600, &attr)
+	if err != nil {
+		return err
+	}
+	defer syscall.Close(mqd) //nolint:errcheck
+	defer mqUnlink(name)     //nolint:errcheck
+
+	if err := mqNotify(mqd); err != nil {
+		return err
+	}
+	if err := mqGetsetattr(mqd); err != nil {
+		return err
+	}
+
+	deadline := time.Now().Add(2 * time.Second)
+	if err := mqTimedsend(mqd, []byte(mqPayload), 0, deadline); err != nil {
+		return err
+	}
+
+	buf := make([]byte, 128)
+	n, err := mqTimedreceive(mqd, buf, deadline)
+	if err != nil {
+		return err
+	}
+	if got := string(buf[:n]); got != mqPayload {
+		return fmt.Errorf("mq_timedreceive payload = %q, want %q", got, mqPayload)
+	}
+	return nil
+}
+
+func mqOpen(name string, flags int, mode uint32, attr *mqAttr) (int, error) {
+	ptr, err := syscall.BytePtrFromString(name)
+	if err != nil {
+		return 0, fmt.Errorf("queue name: %w", err)
+	}
+	fd, _, errno := syscall.Syscall6(
+		syscall.SYS_MQ_OPEN,
+		uintptr(unsafe.Pointer(ptr)),
+		uintptr(flags),
+		uintptr(mode),
+		uintptr(unsafe.Pointer(attr)),
+		0,
+		0,
+	)
+	if errno != 0 {
+		return 0, fmt.Errorf("mq_open: %w", errno)
+	}
+	return int(fd), nil
+}
+
+func mqUnlink(name string) error {
+	ptr, err := syscall.BytePtrFromString(name)
+	if err != nil {
+		return fmt.Errorf("queue name: %w", err)
+	}
+	_, _, errno := syscall.Syscall(syscall.SYS_MQ_UNLINK, uintptr(unsafe.Pointer(ptr)), 0, 0)
+	if errno != 0 {
+		return fmt.Errorf("mq_unlink: %w", errno)
+	}
+	return nil
+}
+
+func mqNotify(mqd int) error {
+	_, _, errno := syscall.Syscall(syscall.SYS_MQ_NOTIFY, uintptr(mqd), 0, 0)
+	if errno == 0 || errors.Is(errno, syscall.EINVAL) {
+		return nil
+	}
+	return fmt.Errorf("mq_notify: %w", errno)
+}
+
+func mqGetsetattr(mqd int) error {
+	var old mqAttr
+	_, _, errno := syscall.Syscall(
+		syscall.SYS_MQ_GETSETATTR,
+		uintptr(mqd),
+		0,
+		uintptr(unsafe.Pointer(&old)),
+	)
+	if errno != 0 {
+		return fmt.Errorf("mq_getsetattr: %w", errno)
+	}
+	return nil
+}
+
+func mqTimedsend(mqd int, payload []byte, priority uint32, deadline time.Time) error {
+	ts := syscall.NsecToTimespec(deadline.UnixNano())
+	_, _, errno := syscall.Syscall6(
+		syscall.SYS_MQ_TIMEDSEND,
+		uintptr(mqd),
+		uintptr(unsafe.Pointer(&payload[0])),
+		uintptr(len(payload)),
+		uintptr(priority),
+		uintptr(unsafe.Pointer(&ts)),
+		0,
+	)
+	if errno != 0 {
+		return fmt.Errorf("mq_timedsend: %w", errno)
+	}
+	return nil
+}
+
+func mqTimedreceive(mqd int, buf []byte, deadline time.Time) (int, error) {
+	ts := syscall.NsecToTimespec(deadline.UnixNano())
+	var prio uint32
+	n, _, errno := syscall.Syscall6(
+		syscall.SYS_MQ_TIMEDRECEIVE,
+		uintptr(mqd),
+		uintptr(unsafe.Pointer(&buf[0])),
+		uintptr(len(buf)),
+		uintptr(unsafe.Pointer(&prio)),
+		uintptr(unsafe.Pointer(&ts)),
+		0,
+	)
+	if errno != 0 {
+		return 0, fmt.Errorf("mq_timedreceive: %w", errno)
+	}
+	return int(n), nil
+}
diff --git a/cmd/ioworkload/scenarios.go b/cmd/ioworkload/scenarios.go
index 79d4e6d..7ca5aa4 100644
--- a/cmd/ioworkload/scenarios.go
+++ b/cmd/ioworkload/scenarios.go
@@ -34,6 +34,7 @@ var scenarios = map[string]func() error{
 	"pipe2-basic":                   pipe2Basic,
 	"eventfd-basic":                 eventfdBasic,
 	"eventfd2-basic":                eventfd2Basic,
+	"mq-posix-basic":                mqPosixBasic,
 	"mountfs-management":            mountfsManagement,
 	"polling-epoll":                 pollingEpoll,
 	"sleep-syscalls":                sleepSyscalls,