netlink/rdma_link_linux.go

113 lines
2.8 KiB
Go

package netlink
import (
"bytes"
"encoding/binary"
"fmt"
"net"
"github.com/vishvananda/netlink/nl"
"golang.org/x/sys/unix"
)
// LinkAttrs represents data shared by most link types
type RdmaLinkAttrs struct {
Index uint32
Name string
FirmwareVersion string
NodeGuid string
SysImageGuid string
}
// Link represents a rdma device from netlink.
type RdmaLink struct {
Attrs RdmaLinkAttrs
}
func getProtoField(clientType int, op int) int {
return ((clientType << nl.RDMA_NL_GET_CLIENT_SHIFT) | op)
}
func uint64ToGuidString(guid uint64) string {
//Convert to byte array
sysGuidBytes := new(bytes.Buffer)
binary.Write(sysGuidBytes, binary.LittleEndian, guid)
//Convert to HardwareAddr
sysGuidNet := net.HardwareAddr(sysGuidBytes.Bytes())
//Get the String
return sysGuidNet.String()
}
func executeOneGetRdmaLink(data []byte) (*RdmaLink, error) {
link := RdmaLink{}
reader := bytes.NewReader(data)
for reader.Len() >= 4 {
_, attrType, len, value := parseNfAttrTLV(reader)
switch attrType {
case nl.RDMA_NLDEV_ATTR_DEV_INDEX:
var Index uint32
r := bytes.NewReader(value)
binary.Read(r, nl.NativeEndian(), &Index)
link.Attrs.Index = Index
case nl.RDMA_NLDEV_ATTR_DEV_NAME:
link.Attrs.Name = string(value[0 : len-1])
case nl.RDMA_NLDEV_ATTR_FW_VERSION:
link.Attrs.FirmwareVersion = string(value[0 : len-1])
case nl.RDMA_NLDEV_ATTR_NODE_GUID:
var guid uint64
r := bytes.NewReader(value)
binary.Read(r, nl.NativeEndian(), &guid)
link.Attrs.NodeGuid = uint64ToGuidString(guid)
case nl.RDMA_NLDEV_ATTR_SYS_IMAGE_GUID:
var sysGuid uint64
r := bytes.NewReader(value)
binary.Read(r, nl.NativeEndian(), &sysGuid)
link.Attrs.SysImageGuid = uint64ToGuidString(sysGuid)
}
if (len % 4) != 0 {
// Skip pad bytes
reader.Seek(int64(4-(len%4)), seekCurrent)
}
}
return &link, nil
}
func execRdmaGetLink(req *nl.NetlinkRequest, name string) (*RdmaLink, error) {
msgs, err := req.Execute(unix.NETLINK_RDMA, 0)
if err != nil {
return nil, err
}
for _, m := range msgs {
link, err := executeOneGetRdmaLink(m)
if err != nil {
return nil, err
}
if link.Attrs.Name == name {
return link, nil
}
}
return nil, fmt.Errorf("Rdma device %v not found", name)
}
// RdmaLinkByName finds a link by name and returns a pointer to the object if
// found and nil error, otherwise returns error code.
func RdmaLinkByName(name string) (*RdmaLink, error) {
return pkgHandle.RdmaLinkByName(name)
}
// RdmaLinkByName finds a link by name and returns a pointer to the object if
// found and nil error, otherwise returns error code.
func (h *Handle) RdmaLinkByName(name string) (*RdmaLink, error) {
proto := getProtoField(nl.RDMA_NL_NLDEV, nl.RDMA_NLDEV_CMD_GET)
req := h.newNetlinkRequest(proto, unix.NLM_F_ACK|unix.NLM_F_DUMP)
return execRdmaGetLink(req, name)
}