Similar to the typed encoding layer, add some decoding type machinery. Add a simple macro `nvkv_decode!` which implements `Schema` for a struct by composing visit calls to each member. Add some common `Schema` kinds, such as `Array` which collects an array value into a fixed maximum size array, and `Required` which fails a decode if the value is not sent.
Signed-off-by: Eliot Courtney <[email protected]> --- drivers/gpu/nova-core/gsp/nvkv.rs | 10 +- drivers/gpu/nova-core/gsp/nvkv/decode.rs | 708 ++++++++++++++++++++++++++++++- 2 files changed, 715 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/nova-core/gsp/nvkv.rs b/drivers/gpu/nova-core/gsp/nvkv.rs index 153aeb8d08d0..9a4f3e40f811 100644 --- a/drivers/gpu/nova-core/gsp/nvkv.rs +++ b/drivers/gpu/nova-core/gsp/nvkv.rs @@ -9,7 +9,7 @@ //! speaking, the function calls will map to some struct - for example, f(GPU_NAME_STRING_KEY, 0, //! b"some gpu") naturally maps to storing a &str with the GPU name. -#![expect(unused_imports)] +#![cfg_attr(not(CONFIG_KUNIT = "y"), expect(unused_imports))] use core::{ marker::PhantomData, @@ -22,7 +22,8 @@ use kernel::{ alloc::{ allocator::KVmalloc, - Allocator, // + Allocator, + ArrayVec, // }, bitfield, num::Bounded, @@ -154,6 +155,11 @@ pub(crate) fn new(index: Index, value: T) -> Self { } } +/// A schema field for an array value under the NVKV key `KEY_ID`. +pub(crate) struct Array<T, const N: usize, const KEY_ID: KeyId> { + vec: ArrayVec<T, N>, +} + bitfield! { /// The op word that starts each NVKV operation. struct Op(u64) { diff --git a/drivers/gpu/nova-core/gsp/nvkv/decode.rs b/drivers/gpu/nova-core/gsp/nvkv/decode.rs index 6496fab1c0c6..43693cb4d31c 100644 --- a/drivers/gpu/nova-core/gsp/nvkv/decode.rs +++ b/drivers/gpu/nova-core/gsp/nvkv/decode.rs @@ -3,11 +3,25 @@ #![cfg_attr(not(CONFIG_KUNIT = "y"), expect(dead_code))] -use kernel::prelude::*; +use core::{ + convert::Infallible, + marker::PhantomData, // +}; + +use kernel::{ + alloc::ArrayVec, + prelude::*, // +}; +use pin_init::{ + init_array_from_fn, + stack_try_pin_init, // +}; use crate::{ gsp::nvkv::{ + Array, Index, + Key, KeyId, Op, Opcode, // @@ -15,6 +29,445 @@ num::IntoSafeCast, // }; +/// Defines a schema struct together with its [`Schema`] and [`Visit`] implementations that decode +/// into `$target`. +/// +/// Each member of the struct should implement [`Schema`] and [`Visit`]. For every +/// `(key, index, value)` triple decoded from the NVKV stream, the generated parent [`Visit`] +/// implementation will call each member in declaration order with that triple. If a member consumes +/// that triple, it will stop there. Otherwise it will keep going until all members are tried. +/// +/// The schema struct holds the state required by the schema implementation to do the decode. It's +/// recommended to use one of the existing [`Schema`] kinds ([`Required`], [`Optional`], +/// [`Accumulated`], [`Key`], [`Array`], [`TruncatingArray`], [`Indexed`]) for each member. +/// +/// Use a lifetime on the schema struct if you want to borrow data directly from the encoded stream, +/// for example, `Key<&'d [u8], KEY>`. +/// +/// # Examples +/// +/// ``` +/// nvkv_decode! { +/// struct RequestSchema => Request { +/// id: Required<Key<u32, 0x0001>>, +/// name: Array<u8, 64, 0x0002>, +/// } +/// } +/// +/// nvkv_decode! { +/// struct NameSchema<'d> => Name<'d> { +/// name: Key<&'d [u8], 0x0002>, +/// } +/// } +/// ``` +#[cfg_attr(not(CONFIG_KUNIT = "y"), expect(unused_macros))] +macro_rules! nvkv_decode { + // A schema which doesn't borrow from the stream. The macro uses a generic lifetime for the + // [`Visit`] implementation but not for the struct itself. This allows omitting the unused + // lifetime on the struct. + ( + $(#[$attr:meta])* + $vis:vis struct $name:ident => $target:ty { $($fields:tt)* } + ) => { + $crate::gsp::nvkv::nvkv_decode!( + @impl ['data] [] $(#[$attr])* $vis struct $name => $target { $($fields)* } + ); + }; + // A schema which borrows from the stream for lifetime `$datalt`. The macro connects the + // [`Visit`] lifetime with the struct lifetime. + ( + $(#[$attr:meta])* + $vis:vis struct $name:ident<$datalt:lifetime> => $target:ty { $($fields:tt)* } + ) => { + $crate::gsp::nvkv::nvkv_decode!( + @impl [$datalt] [<$datalt>] $(#[$attr])* $vis struct $name => $target { $($fields)* } + ); + }; + (@impl [$datalt:lifetime] [$($generics:tt)*] + $(#[$attr:meta])* + $vis:vis struct $name:ident => $target:ty { + $( + $(#[$field_attr:meta])* + $field_vis:vis $field:ident : $ty:ty + ),* $(,)? + } + ) => { + $(#[$attr])* + $vis struct $name $($generics)* { + $( + $(#[$field_attr])* + $field_vis $field: $ty, + )* + } + + impl $($generics)* $crate::gsp::nvkv::Schema for $name $($generics)* { + type Target = $target; + + fn init() -> impl ::kernel::prelude::Init<Self> { + ::pin_init::init!(Self { + $( $field <- <$ty as $crate::gsp::nvkv::Schema>::init(), )* + }) + } + + fn finish( + &mut self, + ) -> impl ::kernel::prelude::Init<Self::Target, ::kernel::error::Error> + '_ { + let Self { $($field,)* } = self; + ::kernel::try_init!(Self::Target { + $( $field <- $crate::gsp::nvkv::Schema::finish($field), )* + }? ::kernel::error::Error) + } + } + + impl<$datalt> $crate::gsp::nvkv::Visit<$datalt> for $name $($generics)* { + fn visit( + &mut self, + key: $crate::gsp::nvkv::KeyId, + index: $crate::gsp::nvkv::Index, + value: $crate::gsp::nvkv::DecoderValue<$datalt>, + ) -> ::kernel::error::Result<bool> { + // TODO: This performs worst-case O(#fields) visit calls. Consider optimising this + // if it becomes a problem. + Ok(false + $( || $crate::gsp::nvkv::Visit::visit(&mut self.$field, key, index, value)? )*) + } + } + }; +} +pub(crate) use nvkv_decode; + +impl<T: Default, const KEY_ID: KeyId, As> Schema for Key<T, KEY_ID, As> { + type Target = T; + + fn init() -> impl Init<Self> { + Self::default() + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + const_assert!( + size_of::<T>() <= 32, + "`Key` here would materialize too large a value on the stack" + ); + + Ok(core::mem::take(&mut self.0)) + } +} + +impl<'data, T, const KEY_ID: KeyId, As> Visit<'data> for Key<T, KEY_ID, As> +where + As: TryFrom<DecoderValue<'data>, Error = Error>, + T: TryFrom<As>, + Error: From<<T as TryFrom<As>>::Error>, +{ + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + if key != KEY_ID { + Ok(false) + } else if index != Index::new::<0>() { + // Single values being set must be at index 0. + Err(EINVAL) + } else { + // Overwrite and take the latest value here. + self.0 = T::try_from(As::try_from(value)?)?; + Ok(true) + } + } +} + +impl<T: Copy, const N: usize, const KEY_ID: KeyId> Schema for Array<T, N, KEY_ID> { + type Target = ArrayVec<T, N>; + + fn init() -> impl Init<Self> { + init!(Self { + vec <- ArrayVec::init_with::<Infallible>(|_| Ok(())), + }) + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + ArrayVec::init_with(move |dst| { + dst.extend_from_slice(&self.vec)?; + self.vec.clear(); + Ok(()) + }) + } +} + +impl<'data, T: Copy + 'data, const N: usize, const KEY_ID: KeyId> Visit<'data> + for Array<T, N, KEY_ID> +where + &'data [T]: TryFrom<DecoderValue<'data>, Error = Error>, +{ + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + if key != KEY_ID { + return Ok(false); + } + // Require to be at index 0 + if index != Index::new::<0>() { + return Err(EINVAL); + } + // Reject oversized and take the latest value. + self.vec.clear(); + self.vec.extend_from_slice(value.try_into()?)?; + Ok(true) + } +} + +/// A schema field for an array value under the NVKV key `KEY_ID` that keeps at most `N` elements. +/// +/// Unlike [`Array`], a longer value is truncated to its first `N` elements instead of failing the +/// decode. +pub(crate) struct TruncatingArray<T, const N: usize, const KEY_ID: KeyId> { + vec: ArrayVec<T, N>, +} + +impl<T: Copy, const N: usize, const KEY_ID: KeyId> Schema for TruncatingArray<T, N, KEY_ID> { + type Target = ArrayVec<T, N>; + + fn init() -> impl Init<Self> { + init!(Self { + vec <- ArrayVec::init_with::<Infallible>(|_| Ok(())), + }) + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + ArrayVec::init_with(move |dst| { + dst.extend_from_slice(&self.vec)?; + self.vec.clear(); + Ok(()) + }) + } +} + +impl<'data, T: Copy + 'data, const N: usize, const KEY_ID: KeyId> Visit<'data> + for TruncatingArray<T, N, KEY_ID> +where + &'data [T]: TryFrom<DecoderValue<'data>, Error = Error>, +{ + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + if key != KEY_ID { + return Ok(false); + } + // Arrays must be at index 0. + if index != Index::new::<0>() { + return Err(EINVAL); + } + let elems: &[T] = value.try_into()?; + // Take the latest value, keeping its first `N` elements. + self.vec.clear(); + self.vec + .extend_from_slice(elems.get(..N).unwrap_or(elems))?; + Ok(true) + } +} + +/// A schema field that marks a child [`Schema`] as required. +/// +/// `finish` fails with [`EINVAL`] if the child consumed no value. +pub(crate) struct Required<S> { + inner: S, + parsed: bool, +} + +impl<S: Schema> Schema for Required<S> { + type Target = S::Target; + + fn init() -> impl Init<Self> { + init!(Self { + inner <- S::init(), + parsed: false, + }) + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + let parsed = core::mem::take(&mut self.parsed); + self.inner + .finish() + .chain(move |_| if parsed { Ok(()) } else { Err(EINVAL) }) + } +} + +impl<'data, S: Visit<'data>> Visit<'data> for Required<S> { + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + let consumed = self.inner.visit(key, index, value)?; + self.parsed |= consumed; + Ok(consumed) + } +} + +/// A schema field which marks a child [`Schema`] as optional. +pub(crate) struct Optional<S> { + inner: S, + parsed: bool, +} + +impl<S: Schema> Schema for Optional<S> +where + S::Target: Default + Unpin, +{ + type Target = Option<S::Target>; + + fn init() -> impl Init<Self> { + init!(Self { + inner <- S::init(), + parsed: false, + }) + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + const_assert!( + size_of::<Self::Target>() <= 512, + "`Optional` here would materialize too large a value on the stack" + ); + + if !core::mem::take(&mut self.parsed) { + return Ok(None); + } + stack_try_pin_init!(let value: S::Target =? self.inner.finish()); + Ok(Some(core::mem::take(value.get_mut()))) + } +} + +impl<'data, S: Visit<'data>> Visit<'data> for Optional<S> { + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + let consumed = self.inner.visit(key, index, value)?; + self.parsed |= consumed; + Ok(consumed) + } +} + +/// Expects objects specified sequentially with index starting from zero. +/// +/// This stores two [`Schema`]s which are initially empty. A [`Schema`] is expected to be complete +/// when we get the next index. +pub(crate) struct Accumulated<S: Schema> { + // Tracks the current index (starting from 0). When this advances, the schema `current` must be + // finished. + current_index: Index, + + // The current `Schema` being constructed now. + current: S, + + // Tracks empty schemas (one that has never consumed a key via `visit`), so we don't call + // `finish` on them. + current_started: bool, + + // The next `Schema` to be constructed. This is required because we must consume a key intended + // for this Schema from the next index to know we can try calling `finish` on `current`. + next: S, + + // The set of results generated by the completed schemas so far. + accumulated: KVVec<S::Target>, +} + +impl<S: Schema> Schema for Accumulated<S> { + type Target = KVVec<S::Target>; + + fn init() -> impl Init<Self> { + init!(Self { + current_index: Index::new::<0>(), + current <- S::init(), + current_started: false, + next <- S::init(), + accumulated: KVVec::new(), + }) + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + if self.current_started { + self.accumulated + .try_push_init(self.current.finish(), GFP_KERNEL)?; + self.current_started = false; + } + self.current_index = Index::new::<0>(); + Ok(core::mem::take(&mut self.accumulated)) + } +} + +impl<'data, S: Schema + Visit<'data>> Visit<'data> for Accumulated<S> { + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + if index != self.current_index { + if !self.next.visit(key, Index::new::<0>(), value)? { + // Unrelated key to us. + return Ok(false); + } + + // Require that objects at index k have all their keys sent before the k + 1 th object + // can be completed. Require that objects are sent contiguously in order from index 0. + if !self.current_started || index != self.current_index + 1 { + return Err(EINVAL); + } + + // The current value must be finished. Push it and swap in `next`. + self.accumulated + .try_push_init(self.current.finish(), GFP_KERNEL)?; + core::mem::swap(&mut self.current, &mut self.next); + self.current_started = true; + self.current_index = index; + Ok(true) + } else { + let consumed = self.current.visit(key, Index::new::<0>(), value)?; + self.current_started |= consumed; + Ok(consumed) + } + } +} + +/// A schema field that scatters indexed values into an array of `N` slots. +/// +/// Values are decoded from the encoded stream using the type `As`, but then converted into `T` with +/// [`From`], like the `As` parameter of [`Key`]. +pub(crate) struct Indexed<T, const N: usize, const KEY_ID: KeyId, As = T> { + slots: [T; N], + _as: PhantomData<As>, +} + +/// Copies `elems`, converted to `T`, into `slots` at `start`. +/// +/// Fails with [`EINVAL`] if the window does not fit in `slots`. +fn scatter_window<T: From<As>, As: Copy>(slots: &mut [T], start: usize, elems: &[As]) -> Result { + let end = start.checked_add(elems.len()).ok_or(EINVAL)?; + // Reject indices outside of the declared array size. + let dst = slots.get_mut(start..end).ok_or(EINVAL)?; + for (d, &e) in dst.iter_mut().zip(elems) { + *d = T::from(e); + } + Ok(()) +} + +impl<T: Default, const N: usize, const KEY_ID: KeyId, As> Schema for Indexed<T, N, KEY_ID, As> { + type Target = [T; N]; + + fn init() -> impl Init<Self> { + init!(Self { + slots <- init_array_from_fn(|_| T::default()), + _as: PhantomData, + }) + } + + fn finish(&mut self) -> impl Init<Self::Target, Error> + '_ { + init_array_from_fn(|i| Ok::<_, Error>(core::mem::take(&mut self.slots[i]))) + } +} + +impl<'data, T, const N: usize, const KEY_ID: KeyId, As> Visit<'data> for Indexed<T, N, KEY_ID, As> +where + T: From<As>, + As: Copy + TryFrom<DecoderValue<'data>, Error = Error> + 'data, + &'data [As]: TryFrom<DecoderValue<'data>, Error = Error>, +{ + fn visit(&mut self, key: KeyId, index: Index, value: DecoderValue<'data>) -> Result<bool> { + if key != KEY_ID { + return Ok(false); + } + let start = index.cast::<usize>().get(); + // Accept both scalar vs scattered array setting for flexibility. + match <&[As]>::try_from(value) { + Ok(elems) => scatter_window(&mut self.slots, start, elems)?, + Err(_) => scatter_window(&mut self.slots, start, &[As::try_from(value)?])?, + } + Ok(true) + } +} + /// A decoded NVKV value. #[derive(Copy, Clone, Debug, PartialEq, Eq)] pub(crate) enum DecoderValue<'a> { @@ -312,6 +765,133 @@ fn decode_unknown_key() -> Result { Ok(()) } + // Tests that decoding via the `nvkv_decode!` macro works correctly. + #[test] + fn decode_typed_struct() -> Result { + const SCALAR32_KEY: KeyId = 0x1234; + const SCALAR64_KEY: KeyId = 0x1235; + const ARRAY8_KEY: KeyId = 0x1236; + const ARRAY32_KEY: KeyId = 0x1237; + const ARRAY64_KEY: KeyId = 0x1238; + const OPT_PRESENT_KEY: KeyId = 0x1239; + const OPT_ABSENT_KEY: KeyId = 0x123a; + const OPT_ARRAY_KEY: KeyId = 0x123b; + const TRUNCATED_KEY: KeyId = 0x123c; + const CONVERTED_KEY: KeyId = 0x123d; + const X_KEY: KeyId = 0x0100; + const Y_KEY: KeyId = 0x0101; + const SLOT_KEY: KeyId = 0x0200; + + const SCALAR32_VALUE: u32 = 0x89ab_cdef; + const SCALAR64_VALUE: u64 = 0x0123_4567_89ab_cdef; + const ARRAY8_VALUE: &[u8] = &[0x12, 0x34, 0x56]; + const ARRAY32_VALUE: &[u32] = &[0x0123_4567, 0x89ab_cdef]; + const ARRAY64_VALUE: &[u64] = &[0x0123_4567_89ab_cdef, 0xfedc_ba98_7654_3210]; + const OPT_PRESENT_VALUE: u32 = 0x55; + const OPT_ARRAY_VALUE: &[u8] = &[0x77, 0x88]; + const TRUNCATED_VALUE: &[u8] = &[0x9a, 0xbc, 0xde]; + const CONVERTED_VALUE: u32 = 0x66; + + // A value that is decoded from the `u32` it converts from. + #[derive(Default)] + struct Converted(u32); + + impl From<u32> for Converted { + fn from(value: u32) -> Self { + Self(value) + } + } + + nvkv_decode! { + struct PairSchema => Pair { + x: Required<Key<u32, X_KEY>>, + y: Required<Key<u32, Y_KEY>>, + } + } + + struct Pair { + x: u32, + y: u32, + } + + nvkv_decode! { + struct TestSchema => TestDecodable { + scalar32: Required<Key<u32, SCALAR32_KEY>>, + scalar64: Required<Key<u64, SCALAR64_KEY>>, + array8: Array<u8, 64, ARRAY8_KEY>, + array32: Array<u32, 64, ARRAY32_KEY>, + array64: Array<u64, 32, ARRAY64_KEY>, + opt_present: Optional<Key<u32, OPT_PRESENT_KEY>>, + opt_absent: Optional<Key<u32, OPT_ABSENT_KEY>>, + opt_array: Optional<Array<u8, 4, OPT_ARRAY_KEY>>, + truncated: TruncatingArray<u8, 2, TRUNCATED_KEY>, + converted: Key<Converted, CONVERTED_KEY, u32>, + pairs: Accumulated<PairSchema>, + slots: Indexed<u32, 4, SLOT_KEY>, + } + } + + struct TestDecodable { + scalar32: u32, + scalar64: u64, + array8: ArrayVec<u8, 64>, + array32: ArrayVec<u32, 64>, + array64: ArrayVec<u64, 32>, + opt_present: Option<u32>, + opt_absent: Option<u32>, + opt_array: Option<ArrayVec<u8, 4>>, + truncated: ArrayVec<u8, 2>, + converted: Converted, + pairs: KVVec<Pair>, + slots: [u32; 4], + } + + let index0 = Index::new::<0>(); + let index1 = Index::new::<1>(); + let index2 = Index::new::<2>(); + let mut encoder = Encoder::new(); + encoder.encode_u32(SCALAR32_KEY, index0, SCALAR32_VALUE)?; + encoder.encode_u64(SCALAR64_KEY, index0, SCALAR64_VALUE)?; + encoder.encode_array8(ARRAY8_KEY, index0, ARRAY8_VALUE)?; + encoder.encode_array32(ARRAY32_KEY, index0, ARRAY32_VALUE)?; + encoder.encode_array64(ARRAY64_KEY, index0, ARRAY64_VALUE)?; + encoder.encode_u32(OPT_PRESENT_KEY, index0, OPT_PRESENT_VALUE)?; + encoder.encode_array8(OPT_ARRAY_KEY, index0, OPT_ARRAY_VALUE)?; + encoder.encode_array8(TRUNCATED_KEY, index0, TRUNCATED_VALUE)?; + encoder.encode_u32(CONVERTED_KEY, index0, CONVERTED_VALUE)?; + encoder.encode_u32(X_KEY, index0, 1)?; + encoder.encode_u32(Y_KEY, index0, 2)?; + encoder.encode_u32(SLOT_KEY, index1, 20)?; + encoder.encode_u32(X_KEY, index1, 3)?; + encoder.encode_u32(Y_KEY, index1, 4)?; + encoder.encode_u32(SLOT_KEY, index0, 10)?; + encoder.encode_array32(SLOT_KEY, index2, &[30, 40])?; + let serialized = encoder.finish(); + + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(TestSchema::init(), GFP_KERNEL)?; + let decoded = KBox::try_init(decoder.decode(&mut *schema)?, GFP_KERNEL)?; + + assert_eq!(decoded.scalar32, SCALAR32_VALUE); + assert_eq!(decoded.scalar64, SCALAR64_VALUE); + assert_eq!(*decoded.array8, *ARRAY8_VALUE); + assert_eq!(*decoded.array32, *ARRAY32_VALUE); + assert_eq!(*decoded.array64, *ARRAY64_VALUE); + assert_eq!(decoded.opt_present, Some(OPT_PRESENT_VALUE)); + assert_eq!(decoded.opt_absent, None); + assert_eq!(decoded.opt_array.as_deref(), Some(OPT_ARRAY_VALUE)); + assert_eq!(*decoded.truncated, TRUNCATED_VALUE[..2]); + assert_eq!(decoded.converted.0, CONVERTED_VALUE); + assert_eq!(decoded.pairs.len(), 2); + assert_eq!(decoded.pairs[0].x, 1); + assert_eq!(decoded.pairs[0].y, 2); + assert_eq!(decoded.pairs[1].x, 3); + assert_eq!(decoded.pairs[1].y, 4); + assert_eq!(decoded.slots, [10, 20, 30, 40]); + + Ok(()) + } + /// Records each visit as `(key, index, value)`, for tests on hand-built streams. #[derive(Default)] struct Recorder<'d> { @@ -500,4 +1080,130 @@ fn decode_raw_words_malformed() -> Result { Ok(()) } + + // Tests the error paths of the schema kinds. + #[test] + fn decode_typed_struct_errors() -> Result { + const VALUE_KEY: KeyId = 0x2200; + const SLOT_KEY: KeyId = 0x2201; + const BLOB_KEY: KeyId = 0x2202; + const X_KEY: KeyId = 0x2203; + const Y_KEY: KeyId = 0x2204; + + let index0 = Index::new::<0>(); + let index1 = Index::new::<1>(); + let index2 = Index::new::<2>(); + + nvkv_decode! { + struct ValueSchema => Value { + value: Key<u32, VALUE_KEY>, + } + } + + struct Value { + value: u32, + } + + // A single value at a non-zero index. + let mut encoder = Encoder::new(); + encoder.encode_u32(VALUE_KEY, index1, 1)?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(ValueSchema::init(), GFP_KERNEL)?; + assert!(decoder.decode(&mut *schema).is_err()); + + // A 64-bit value for a 32-bit key. + let mut encoder = Encoder::new(); + encoder.encode_u64(VALUE_KEY, index0, 1)?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(ValueSchema::init(), GFP_KERNEL)?; + assert!(decoder.decode(&mut *schema).is_err()); + + nvkv_decode! { + struct SlotsSchema => Slots { + slots: Indexed<u32, 2, SLOT_KEY>, + } + } + + struct Slots { + slots: [u32; 2], + } + + // An index past the declared slots. + let mut encoder = Encoder::new(); + encoder.encode_u32(SLOT_KEY, index2, 1)?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(SlotsSchema::init(), GFP_KERNEL)?; + assert!(decoder.decode(&mut *schema).is_err()); + + nvkv_decode! { + struct BlobSchema => Blob { + blob: Array<u8, 4, BLOB_KEY>, + } + } + + struct Blob { + blob: ArrayVec<u8, 4>, + } + + // An array longer than the declared capacity. + let mut encoder = Encoder::new(); + encoder.encode_array8(BLOB_KEY, index0, &[0; 5])?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(BlobSchema::init(), GFP_KERNEL)?; + assert!(decoder.decode(&mut *schema).is_err()); + + nvkv_decode! { + struct PairSchema => Pair { + x: Required<Key<u32, X_KEY>>, + y: Required<Key<u32, Y_KEY>>, + } + } + + struct Pair { + x: u32, + y: u32, + } + + // Required keys that are missing are an error. + let mut encoder = Encoder::new(); + encoder.encode_u32(X_KEY, index0, 1)?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(PairSchema::init(), GFP_KERNEL)?; + let init = decoder.decode(&mut *schema)?; + assert!(KBox::try_init(init, GFP_KERNEL).is_err()); + + nvkv_decode! { + struct PairsSchema => Pairs { + pairs: Accumulated<PairSchema>, + } + } + + struct Pairs { + pairs: KVVec<Pair>, + } + + // Accumulated objects must start at index 0. + let mut encoder = Encoder::new(); + encoder.encode_u32(X_KEY, index1, 1)?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(PairsSchema::init(), GFP_KERNEL)?; + assert!(decoder.decode(&mut *schema).is_err()); + + // Accumulated objects must be complete before the next one starts. + let mut encoder = Encoder::new(); + encoder.encode_u32(X_KEY, index0, 1)?; + encoder.encode_u32(X_KEY, index1, 2)?; + let serialized = encoder.finish(); + let decoder = Decoder::new(&serialized, UnknownKeyPolicy::Error); + let mut schema = KBox::init(PairsSchema::init(), GFP_KERNEL)?; + assert!(decoder.decode(&mut *schema).is_err()); + + Ok(()) + } } -- 2.56.0
