Enum syscall::io_uring::v1::StandardOpcode

#[repr(u8)]#[non_exhaustive]pub enum StandardOpcode {
    NoOp,
    Open,
    Close,
    Read,
    Write,
    Seek,
    Fstat,
    Fstatvfs,
    Mmap,
    Munmap,
    Fsync,
    FilesUpdate,
    RegularSyscall,
}

The standard opcodes, which are a superset of the filesystem (scheme-compatible) syscalls. Opcodes with a value above 127 are specific to the producer; the kernel for example, also has syscalls for managing memory and processes, while a userspace producer such as nvmed can provide custom messages for things like TRIM.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

NoOp

A no-operation, using only the implicit fields. Useful for testing or benchmarking io_uring operation.

Open

A call that opens a file, given a path represented as a string. Uses all implicit fields.

required field	usage description	SIZE
syscall_flags	OpenFlags	BOTH
addr	a pointer to a buffer containing the path	BOTH
len	the length of the buffer containing the path	BOTH
fd	if OPEN_AT, points to an fd referencing the parent	BOTH
offset	fcntl flags (upper), file mode if O_CREAT (lower)	BOTH
additional1	not used/producer specific	64
additional2	not used/producer specific	64

Close

A call that closes a file, flushing required buffers if told to. Uses all implicit fields. On failure, returns the number of successfully closed file descriptors, or zero unless CLOSE_MANY.

required field	usage description	SIZE
syscall_flags	CloseFlags	BOTH
addr	not used/producer specific	BOTH
len	if CLOSE_MANY, gives the count of the range of fds	BOTH
fd	the file descriptor to close, or start if CLOSE_MANY	BOTH
offset	not used/producer specific	BOTH
additional1	not used/producer specific	64
additional2	not used/producer specific	64

Read

A call that reads bytes from a file descriptor. Uses all implicit fields.

required field	usage description	SIZE
syscall_flags	ReadFlags	BOTH
addr	the address to read into	BOTH
len	the number of iovecs if VECTORED, otherwise the size	BOTH
fd	the file descriptor to read from	BOTH
offset	the offset to read from unless CHANGE_OFFSET	BOTH
additional1	not used/producer specific	64
additional2	not used/producer specific	64

Write

A call that reads bytes from a file. Uses all implicit fields.

required field	usage description	SIZE
syscall_flags	WriteFlags	BOTH
addr	the address to write from	BOTH
len	the number of iovecs if VECTORED, otherwise the size	BOTH
fd	the file descriptor to write to	BOTH
offset	the offset to write to unless CHANGE_OFFSET	BOTH
additional1	not used/producer specific	64
additional2	not used/producer specific	64

Seek

A call that changes the current file offset. Uses all implicit fields.

required field	usage description	SIZE
syscall_flags	whence arg (SEEK_SET, SEEK_END, or SEEK_CUR	BOTH
addr	not used/producer specific	BOTH
len	not used/producer specific	BOTH
fd	the file descriptor which offset will be changed	BOTH
offset	a signed integer which is added to the offset from whence	BOTH
additional1	not used/producer specific	64
additional2	not used/producer specific	64

Fstat

TODO

Fstatvfs

TODO

Mmap

TODO

Munmap

TODO

Fsync

TODO

FilesUpdate

A call that when submitted, sends one completion entry for every update to a file or set of files, when the update matched the specific flags. If the flags field contains IoUringSqeFlags::SUBSCRIBE, there will be one completio for each event, otherwise only a single event. Uses all implicit fields.

required field	usage description	SIZE
syscall_flags	FilesUpdateFlags	BOTH
addr	if MULTI, the address of an array of fds	BOTH
fd	if not MULTI, the fd to follow, otherwise unused	BOTH
offset	not used/producer specific	BOTH
len	if MULTI, the number of fds in the array	BOTH
additional1	not used/producer specifc	64
additional2	not used/producer specific	64

RegularSyscall

A syscall where the four syscall parameters, namely the number (a), b, c, and d, all are passed through as if they were a regular scheme packet. The size of file descriptors will be limited to 32 bits if SqEntry32 is used. Uses all implicit fields. This allows talking to schemes asynchronously and without blocking, for other syscalls than read and write, with a proper wakeup system.

required field	usage description	SIZE
syscall_flags	fcntl F_SETFL flags, e.g. O_NONBLOCK or O_DIRECT	BOTH
addr	the "a" field of the syscall, which is the syscall number	BOTH
fd	the "b" field, which typically is the file descriptor	BOTH
offset	the "c" field, which usually is the pointer to a buffer	BOTH
len	the "d" field, which usually is the length of a buffer	BOTH
additional1	the "e" field (not scheme compatible yet)	64
additional2	the "f" field (not scheme compatible yet)	64

Implementations

impl StandardOpcode

pub const MAX_OPCODE: u8

The highest opcode number that is reserved to standard opcodes.

pub fn from_raw(raw: u8) -> Option<Self>

Trait Implementations

impl Clone for StandardOpcode

fn clone(&self) -> StandardOpcode

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for StandardOpcode

impl Debug for StandardOpcode

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Eq for StandardOpcode

impl Hash for StandardOpcode

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl PartialEq<StandardOpcode> for StandardOpcode

fn eq(&self, other: &StandardOpcode) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl StructuralEq for StandardOpcode

impl StructuralPartialEq for StandardOpcode