Add support for the Linux PAGEMAP_SCAN ioctl (#11372)

* WIP: use the pagemap_scan ioctl to selectively reset an instance's dirty pages

* Less hacky, and supporting tables, too

* Bugfixes

* WIP: m

Add support for the Linux PAGEMAP_SCAN ioctl (#11372)

* WIP: use the pagemap_scan ioctl to selectively reset an instance's dirty pages

* Less hacky, and supporting tables, too

* Bugfixes

* WIP: memcpy instead of pread

* Refactor support for pagemap

* Don't hold a raw pointer to the original data, plumb through an `Arc`
to have a safe reference instead.
* Update pagemap bindings to latest version of abstraction written.
* Include pagemap-specific tests.
* Use a `PageMap` structure created once-per-pool instead of a
static-with-a-file.
* Refactor to use the "pagemap path" unconditionally which blends in the
keep_resident bits.

* Improve safety documentation

prtest:full

* Fix some lints

* Skip ioctl tests when it's not supported

* Fix a memory leak by moving impls around

* Fix no vm build

* Review comments

* Add more pagemap-specific documentation

* Add more docs, refactor implementation slightly

* Improve `category_*` docs

Basically forward to the Linux kernel source itself.

* Fix compile

* Make pagemap integration resilient across forks

* Fix non-pooling-allocator-build

* Fix portability issues of new test

* Actually use config on macos

---------

Co-authored-by: Till Schneidereit <[email protected]>

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Deny `unsafe_op_in_unsafe_fn` in `wasmtime::runtime::vm` (#11312)

* Deny `unsafe_op_in_unsafe_fn` in `wasmtime::runtime::vm`

Slowly expanding this lint to more of the crate.

prtest:full

* Fix lin

Deny `unsafe_op_in_unsafe_fn` in `wasmtime::runtime::vm` (#11312)

* Deny `unsafe_op_in_unsafe_fn` in `wasmtime::runtime::vm`

Slowly expanding this lint to more of the crate.

prtest:full

* Fix lints in custom module

* Fix some lints with miri

* Fix non-VM build

* Fix arm windows

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Update Wasmtime to the 2024 Rust Edition (#10806)

* Update Wasmtime to the 2024 Rust Edition

Now that our MSRV supports the 2024 edition it's possible to make this
switch. This commit moves Wasmtim

Update Wasmtime to the 2024 Rust Edition (#10806)

* Update Wasmtime to the 2024 Rust Edition

Now that our MSRV supports the 2024 edition it's possible to make this
switch. This commit moves Wasmtime to the 2024 Edition to keep
up-to-date with Rust idioms and access many of the edition features
exclusive to the 2024 edition.

prtest:full

* Reformat with the 2024 edition

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Move MemoryImageSource::map_at to mmap module (#9687)

* Simplify mmap interface slightly

Return a single `SendSyncPtr` -- the platform-independent context converts to
the various raw pointer types

Move MemoryImageSource::map_at to mmap module (#9687)

* Simplify mmap interface slightly

Return a single `SendSyncPtr` -- the platform-independent context converts to
the various raw pointer types as desired. This simplifies upcoming work where I
wanted to return a `SendSyncPtr`.

* Move MemoryImageSource::map_at to mmap module

This is part of the work to centralize memory management into the `mmap`
module. This commit introduces a few structures which aid in that process, and
starts converting one of the functions (`MemoryImageSource::map_at`) into this
module.

The structures introduced are:

* `MemoryBase`: `RuntimeLinearMemory::base_ptr` is now
`RuntimeLinearMemory::base`, which returns a `MemoryBase`. This is either a
raw pointer or an `MmapOffset` as described below.

* `MmapOffset`: A combination of a reference to an mmap and an offset into it.
Logically represents a pointer into a mapped section of memory.

In future work, we'll move more image-mapping code over to `Mmap` instances.

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Add a `signals-based-traps` Cargo compile-time feature (#9614)

* Gate signal handlers behind a new Cargo feature

This commit adds a new on-by-default Cargo feature to the `wasmtime`
crate named `si

Add a `signals-based-traps` Cargo compile-time feature (#9614)

* Gate signal handlers behind a new Cargo feature

This commit adds a new on-by-default Cargo feature to the `wasmtime`
crate named `signals-based-traps`. This is modeled after the
`Config::signals_based_traps` configuration at runtime and can be used
to statically disable the use of signal handlers in Wasmtime. This
notably reduces the number of platform dependencies that Wasmtime has
and provides a mode of avoiding relying on signals altogether.

This introduces a new `MallocMemory` which is a linear memory backed by
the system allocator. This new type of memory is enabled when virtual
memory guards are disabled and signals-based-traps are disabled. This
means that this new type of memory will be candidate for fuzzing for
example.

prtest:full

* Fix rebase conflict

* Refactor `MmapVec` documentation and representation

* Remove no-longer-needed `Arc`
* Document it may be backed by `Vec<u8>`

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Add `anyhow` stuff to our internal `wasmtime` crate prelude (#8804)

* Add `anyhow` stuff to our internal `wasmtime` crate prelude

We use it basically everywhere and it is annoying to have to import

Add `anyhow` stuff to our internal `wasmtime` crate prelude (#8804)

* Add `anyhow` stuff to our internal `wasmtime` crate prelude

We use it basically everywhere and it is annoying to have to import.

I also did an audit of existing `use` statements and removed the now-redundant
ones and replaced one-off imports with usage of the prelude, so that the prelude
is available by default in more places.

* Fix `cargo doc`

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Handle all `decommit`s/`madvise(DONTNEED)`s homogenously (#8587)

* Don't differentiate between decommitting table vs stack pages

All implementations are the same either way, and by treating them di

Handle all `decommit`s/`madvise(DONTNEED)`s homogenously (#8587)

* Don't differentiate between decommitting table vs stack pages

All implementations are the same either way, and by treating them differently,
it makes it difficult to prototype integration with batching syscalls that need
to treat them homogenously.

Co-Authored-By: Jamey Sharp <[email protected]>

* Remove the `madvise_dontneed` function from the system virtual memory interface

This was already implemented by the existing `decommit_pages` function, we just
need to determine what the behavior is for the left over mapping. Specifically,
whether it is zeroed or restored to the original mapping (e.g. a CoW image).

This allows us to handle `decommit_pages` and what previously were calls to
`madvise_dontneed` homogenously, which enables us to prototype new system calls
that batch decommits together and therefore must treat them all the same.

Co-Authored-By: Jamey Sharp <[email protected]>

---------

Co-authored-by: Jamey Sharp <[email protected]>

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Add support for `#![no_std]` to the `wasmtime` crate (#8533)

* Always fall back to custom platform for Wasmtime

This commit updates Wasmtime's platform support to no longer require an
opt-in `RUSTF

Add support for `#![no_std]` to the `wasmtime` crate (#8533)

* Always fall back to custom platform for Wasmtime

This commit updates Wasmtime's platform support to no longer require an
opt-in `RUSTFLAGS` `--cfg` flag to be specified. With `no_std` becoming
officially supported this should provide a better onboarding experience
where the fallback custom platform is used. This will cause linker
errors if the symbols aren't implemented and searching/googling should
lead back to our docs/repo (eventually, hopefully).

* Change Wasmtime's TLS state to a single pointer

This commit updates the management of TLS to rely on just a single
pointer rather than a pair of a pointer and a `bool`. Additionally
management of the TLS state is pushed into platform-specific modules to
enable different means of managing it, namely the "custom" platform now
has a C function required to implement TLS state for Wasmtime.

* Delay conversion to `Instant` in atomic intrinsics

The `Duration` type is available in `no_std` but the `Instant` type is
not. The intention is to only support the `threads` proposal if `std` is
active but to assist with this split push the `Duration` further into
Wasmtime to avoid using a type that can't be mentioned in `no_std`.

* Gate more parts of Wasmtime on the `profiling` feature

Move `serde_json` to an optional dependency and gate the guest profiler
entirely on the `profiling` feature.

* Refactor conversion to `anyhow::Error` in `wasmtime-environ`

Have a dedicated trait for consuming `self` in addition to a
`Result`-friendly trait.

* Gate `gimli` in Wasmtime on `addr2line`

Cut down the dependency list if `addr2line` isn't enabled since then
the dependency is not used. While here additionally lift the version
requirement for `addr2line` up to the workspace level.

* Update `bindgen!` to have `no_std`-compatible output

Pull most types from Wasmtime's `__internal` module as the source of
truth.

* Use an `Option` for `gc_store` instead of `OnceCell`

No need for synchronization here when mutability is already available in
the necessary contexts.

* Enable embedder-defined host feature detection

* Add `#![no_std]` support to the `wasmtime` crate

This commit enables compiling the `runtime`, `gc`, and `component-model`
features of the `wasmtime` crate on targets that do not have `std`. This
tags the crate as `#![no_std]` and then updates everything internally to
import from `core` or `alloc` and adapt for the various idioms. This
ended up requiring some relatively extensive changes, but nothing too
too bad in the grand scheme of things.

* Require `std` for the perfmap profiling agent

prtest:full

* Fix build on wasm

* Fix windows build

* Remove unused import

* Fix Windows/Unix build without `std` feature

* Fix some doc links

* Remove unused import

* Fix build of wasi-common in isolation

* Fix no_std build on macos

* Re-fix build

* Fix standalone build of wasmtime-cli-flags

* Resolve a merge conflict

* Review comments

* Remove unused import

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Turn the `wasmtime-runtime` crate into the `wasmtime::runtime::vm` module (#8501)

* Expose `wasmtime-runtime` as `crate::runtime::vm` internally for the `wasmtime` crate

* Rewrite uses of `wasmtime

Turn the `wasmtime-runtime` crate into the `wasmtime::runtime::vm` module (#8501)

* Expose `wasmtime-runtime` as `crate::runtime::vm` internally for the `wasmtime` crate

* Rewrite uses of `wasmtime_runtime` to `crate::runtime::vm`

* Remove dep on `wasmtime-runtime` from `wasmtime-cli`

* Move the `wasmtime-runtime` crate into the `wasmtime::runtime::vm` module

* Update labeler for merged crates

* Fix `publish verify`

prtest:full

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