pub struct Flags { /* private fields */ }
Expand description
Flags used by multiple Server
methods
Implementations§
source§impl Flags
impl Flags
sourcepub const MAY_TRIM: Self = _
pub const MAY_TRIM: Self = _
This flag is used by the Server::zero
callback.
Indicates that the plugin may punch a hole instead of writing actual zeros, but only if subsequent reads from that region will return zeros. There is no way to disable this flag, although a plugin that does not support trim as a way to write zeroes may ignore the flag without violating expected semantics.
sourcepub const FUA: Self = _
pub const FUA: Self = _
This flag represents Forced Unit Access semantics.
It is used by the Server::write_at
, Server::zero
, and
Server::trim
callbacks to indicate that the plugin must not
return a result until the action has landed in persistent storage.
This flag will not be sent to the plugin unless can_fua
is
provided to plugin!
and Server::can_fua
returns
FuaFlags::Native
.
sourcepub const REQ_ONE: Self = _
pub const REQ_ONE: Self = _
Used with Server::extents
to indicate that the client is only
requesting information about a single extent. The plugin may ignore
this flag, or as an optimization it may return
just a single extent.
sourcepub const FAST_ZERO: Self = _
pub const FAST_ZERO: Self = _
This flag is used by Server::zero
.
If supplied, the plugin must decide up front if the implementation
is likely to be faster than a corresponding Server::write_at
; if
not, then it must immediately fail with ENOTSUP
or
EOPNOTSUPP
and preferably without modifying the exported
image. It is acceptable to always fail a fast zero request (as a
fast failure is better than attempting the write only to find out
after the fact that it was not fast after all). Note that on Linux,
support for ioctl(BLKZEROOUT)
is insufficient for determining
whether a zero request to a block device will be fast (because the
kernel will perform a slow fallback when needed).
sourcepub const fn from_bits(bits: u32) -> Option<Self>
pub const fn from_bits(bits: u32) -> Option<Self>
Convert from underlying bit representation, unless that representation contains bits that do not correspond to a flag.
sourcepub const fn from_bits_truncate(bits: u32) -> Self
pub const fn from_bits_truncate(bits: u32) -> Self
Convert from underlying bit representation, dropping any bits that do not correspond to flags.
sourcepub const unsafe fn from_bits_unchecked(bits: u32) -> Self
pub const unsafe fn from_bits_unchecked(bits: u32) -> Self
Convert from underlying bit representation, preserving all bits (even those not corresponding to a defined flag).
Safety
The caller of the bitflags!
macro can chose to allow or
disallow extra bits for their bitflags type.
The caller of from_bits_unchecked()
has to ensure that
all bits correspond to a defined flag or that extra bits
are valid for this bitflags type.
sourcepub const fn intersects(&self, other: Self) -> bool
pub const fn intersects(&self, other: Self) -> bool
Returns true
if there are flags common to both self
and other
.
sourcepub const fn contains(&self, other: Self) -> bool
pub const fn contains(&self, other: Self) -> bool
Returns true
if all of the flags in other
are contained within self
.
sourcepub fn set(&mut self, other: Self, value: bool)
pub fn set(&mut self, other: Self, value: bool)
Inserts or removes the specified flags depending on the passed value.
sourcepub const fn intersection(self, other: Self) -> Self
pub const fn intersection(self, other: Self) -> Self
Returns the intersection between the flags in self
and
other
.
Specifically, the returned set contains only the flags which are
present in both self
and other
.
This is equivalent to using the &
operator (e.g.
ops::BitAnd
), as in flags & other
.
sourcepub const fn union(self, other: Self) -> Self
pub const fn union(self, other: Self) -> Self
Returns the union of between the flags in self
and other
.
Specifically, the returned set contains all flags which are
present in either self
or other
, including any which are
present in both (see Self::symmetric_difference
if that
is undesirable).
This is equivalent to using the |
operator (e.g.
ops::BitOr
), as in flags | other
.
sourcepub const fn difference(self, other: Self) -> Self
pub const fn difference(self, other: Self) -> Self
Returns the difference between the flags in self
and other
.
Specifically, the returned set contains all flags present in
self
, except for the ones present in other
.
It is also conceptually equivalent to the “bit-clear” operation:
flags & !other
(and this syntax is also supported).
This is equivalent to using the -
operator (e.g.
ops::Sub
), as in flags - other
.
sourcepub const fn symmetric_difference(self, other: Self) -> Self
pub const fn symmetric_difference(self, other: Self) -> Self
Returns the symmetric difference between the flags
in self
and other
.
Specifically, the returned set contains the flags present which
are present in self
or other
, but that are not present in
both. Equivalently, it contains the flags present in exactly
one of the sets self
and other
.
This is equivalent to using the ^
operator (e.g.
ops::BitXor
), as in flags ^ other
.
sourcepub const fn complement(self) -> Self
pub const fn complement(self) -> Self
Returns the complement of this set of flags.
Specifically, the returned set contains all the flags which are
not set in self
, but which are allowed for this type.
Alternatively, it can be thought of as the set difference
between Self::all()
and self
(e.g. Self::all() - self
)
This is equivalent to using the !
operator (e.g.
ops::Not
), as in !flags
.
Trait Implementations§
source§impl BitAndAssign<Flags> for Flags
impl BitAndAssign<Flags> for Flags
source§fn bitand_assign(&mut self, other: Self)
fn bitand_assign(&mut self, other: Self)
Disables all flags disabled in the set.
source§impl BitOrAssign<Flags> for Flags
impl BitOrAssign<Flags> for Flags
source§fn bitor_assign(&mut self, other: Self)
fn bitor_assign(&mut self, other: Self)
Adds the set of flags.
source§impl BitXorAssign<Flags> for Flags
impl BitXorAssign<Flags> for Flags
source§fn bitxor_assign(&mut self, other: Self)
fn bitxor_assign(&mut self, other: Self)
Toggles the set of flags.
source§impl Extend<Flags> for Flags
impl Extend<Flags> for Flags
source§fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)
fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)
source§fn extend_one(&mut self, item: A)
fn extend_one(&mut self, item: A)
extend_one
)source§fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one
)source§impl FromIterator<Flags> for Flags
impl FromIterator<Flags> for Flags
source§fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self
fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self
source§impl Ord for Flags
impl Ord for Flags
source§impl PartialEq<Flags> for Flags
impl PartialEq<Flags> for Flags
source§impl PartialOrd<Flags> for Flags
impl PartialOrd<Flags> for Flags
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl SubAssign<Flags> for Flags
impl SubAssign<Flags> for Flags
source§fn sub_assign(&mut self, other: Self)
fn sub_assign(&mut self, other: Self)
Disables all flags enabled in the set.