You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mem_freebsd.go
    path of file: ./repos/zeebe/clients/go/vendor/github.com/shirou/gopsutil/v3/mem
    
    the code of the file until where you have to start completion: //go:build freebsd
// +build freebsd

package mem

import (
	"context"
	"errors"
	"unsafe"

	"github.com/shirou/gopsutil/v3/internal/common"
	"golang.org/x/sys/unix"
)

func VirtualMemory() (*VirtualMemoryStat, error) {
	return VirtualMemoryWithContext(context.Background())
}

func VirtualMemoryWithContext(ctx context.Context) (
    
func VirtualMemoryWithContext(ctx context.Context) (*VirtualMemoryStat, error) {
	pageSize, err := common.SysctlUint("vm.stats.vm.v_page_size")
	if err != nil {
		return nil, err
	}
	physmem, err := common.SysctlUint("hw.physmem")
	if err != nil {
		return nil, err
	}

	free, err := common.SysctlUint("vm.stats.vm.v_free_count")
	if err != nil {
		return nil, err
	}
	active, err := common.SysctlUint("vm.stats.vm.v_active_count")
	if err != nil {
		return nil, err
	}
	inactive, err := common.SysctlUint("vm.stats.vm.v_inactive_count")
	if err != nil {
		return nil, err
	}
	buffers, err := common.SysctlUint("vfs.bufspace")
	if err != nil {
		return nil, err
	}
	wired, err := common.SysctlUint("vm.stats.vm.v_wire_count")
	if err != nil {
		return nil, err
	}
	var cached, laundry uint64
	osreldate, _ := common.SysctlUint("kern.osreldate")
	if osreldate < 1102000 {
		cached, err = common.SysctlUint("vm.stats.vm.v_cache_count")
		if err != nil {
			return nil, err
		}
	} else {
		laundry, err = common.SysctlUint("vm.stats.vm.v_laundry_count")
		if err != nil {
			return nil, err
		}
	}

	p := pageSize
	ret := &VirtualMemoryStat{
		Total:    physmem,
		Free:     free * p,
		Active:   active * p,
		Inactive: inactive * p,
		Cached:   cached * p,
		Buffers:  buffers,
		Wired:    wired * p,
		Laundry:  laundry * p,
	}

	ret.Available = ret.Inactive + ret.Cached + ret.Free + ret.Laundry
	ret.Used = ret.Total - ret.Available
	ret.UsedPercent = float64(ret.Used) / float64(ret.Total) * 100.0

	return ret, nil
}