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uffd

package module

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Versions in this module

v0

v0.1.0

Mar 13, 2026

Changes in this version

+ const NR_userfaultfd — darwin/amd64, js/wasm, windows/amd64

+ const UFFDIO_API

+ const UFFDIO_COPY

+ const UFFDIO_MOVE

+ const UFFDIO_REGISTER

+ const UFFDIO_REGISTER_MODE_MISSING

+ const UFFD_API

+ const UFFD_EVENT_PAGEFAULT

+ const UFFD_FEATURE_MOVE

+ const UFFD_OPEN_DEFAULT

+ const UFFD_O_CLOEXEC

+ const UFFD_O_NONBLOCK

+ const UFFD_USER_MODE_ONLY

+ var ErrInvalidFDsLength = errors.New("invalid file descriptors length")

+ var ErrInvalidPopulateRange = errors.New("populate range must be page aligned")

+ var ErrUnexpectedEventType = errors.New("unexpected event type")

+ var ErrUnsupportedPlatform = errors.New("userfaultfd is unsupported on this platform")

+ func CheckSupport() error

+ func CheckSupportWithFlags(flags uintptr) error

+ func GetCopyBytes(copy *UffdioCopy) int64

+ func GetMoveBytes(move *UffdioMove) int64

+ func GetMsgArg(msg *UffdMsg) [24]byte

+ func GetMsgEvent(msg *UffdMsg) uint8

+ func GetPagefaultAddress(pagefault *UffdPagefault) uint64

+ func Handle(uffd UFFD, start uintptr, src io.ReaderAt) error

+ func HandleContext(ctx context.Context, uffd UFFD, start uintptr, src io.ReaderAt) error

+ func Populate(uffd UFFD, address uintptr, data []byte) (int64, error) — linux/amd64

+ func PopulateMove(uffd UFFD, address uintptr, data []byte) (int64, error) — linux/amd64

+ func ReceiveFDs(conn *net.UnixConn, num int) ([]uintptr, error)

+ func SendFDs(conn *net.UnixConn, fds []uintptr) error

+ func SendUFFD(conn *net.UnixConn, uffd UFFD, start uintptr) error

+ type Fault struct

+ Address uintptr

+ type Handler struct

+ func NewHandler(uffd UFFD, opts *HandlerOptions) *Handler

+ func (h *Handler) Serve(ctx context.Context, onFault func(Fault, Resolver) error) error

+ type HandlerOptions struct

+ DisableLockOSThread bool

+ PollTimeout time.Duration

+ type MoveBuffer []byte

+ func AllocateMoveBuffer(length int) (MoveBuffer, error)

+ func (b MoveBuffer) Bytes() []byte

+ func (b MoveBuffer) Close() error

+ type Registration struct

+ func Register(length int) (*Registration, error)

+ func RegisterWithFlags(length int, flags uintptr) (*Registration, error)

+ func (r *Registration) Bytes() []byte

+ func (r *Registration) Close() error

+ func (r *Registration) Start() uintptr

+ func (r *Registration) UFFD() UFFD

+ type Resolver struct

+ func (r Resolver) Populate(address uintptr, data []byte) (int64, error)

+ func (r Resolver) PopulateMove(address uintptr, data []byte) (int64, error)

+ type UFFD uintptr

+ func Open(flags uintptr) (UFFD, error)

+ func ReceiveUFFD(conn *net.UnixConn) (UFFD, uintptr, error)

+ func (u UFFD) Close() error

+ func (u UFFD) Init(features uint64) error

+ func (u UFFD) Register(start, length uintptr, mode uint64) error

+ type UffdMsg struct

+ Arg [24]byte

+ Event uint8

+ Reserved1 uint8

+ Reserved2 uint16

+ Reserved3 uint32

+ type UffdPagefault struct

+ Address uint64

+ Feat [4]byte

+ Flags uint64

+ Pad_cgo_0 [4]byte

+ type UffdioAPI struct

+ Api uint64

+ Features uint64

+ Ioctls uint64

+ func NewUffdioAPI(api, features uint64) UffdioAPI

+ type UffdioCopy struct

+ Copy int64

+ Dst uint64

+ Len uint64

+ Mode uint64

+ Src uint64

+ func NewUffdioCopy(b []byte, address uint64, length uint64, mode uint64, copied int64) UffdioCopy

+ type UffdioMove struct

+ Dst uint64

+ Len uint64

+ Mode uint64

+ Move int64

+ Src uint64

+ func NewUffdioMove(b []byte, address uint64, length uint64, mode uint64, moved int64) UffdioMove

+ type UffdioRange struct

+ Len uint64

+ Start uint64

+ type UffdioRegister struct

+ Ioctls uint64

+ Mode uint64

+ Range UffdioRange

+ func NewUffdioRegister(start, length, mode uint64) UffdioRegister