Now that we have our own `Allocator`, `Box` and `Vec` types we can remove
Rust's `alloc` crate and the `new_uninit` unstable feature.

Also remove `Kmalloc`'s `GlobalAlloc` implementation -- we can't remove
this in a separate patch, since the `alloc` crate requires a
`#[global_allocator]` to set, that implements `GlobalAlloc`.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-29-dakr@kernel.org


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Sets the `sysroot` field in rust-project.json which is now needed in
newer versions of rust-analyzer instead of the `sysroot_src` field.

Till [1] `rust-analyzer` used to guess the `sysroot` based on the
`sysroot_src` at [2]. Now `sysroot` is a required parameter for a
`rust-project.json` file. It is required because `rust-analyzer`
need it to find the proc-macro server [3].

In the current version of `rust-analyzer` the `sysroot_src` is only used
to include the inbuilt library crates (std, core, alloc, etc) [4]. Since
we already specify the core library to be included in the
`rust-project.json` we don't need to define the `sysroot_src`.

Code editors like VS Code try to use the latest version of rust-analyzer
(which is updated every week) instead of the version of rust-analyzer
that comes with the rustup toolchain (which is updated every six weeks
along with the rust version).

Without this change `rust-analyzer` is breaking for anyone using VS Code.
As they are getting the latest version of `rust-analyzer` with the
changes made in [1].

`rust-analyzer` will also start breaking for other developers as they
update their rust version (assuming that also updates the rust-analyzer
version on their system).

This patch should work with every setup as there is no more guess work
being done by `rust-analyzer`.

[ Lukas, who leads the rust-analyzer team, says:

    `sysroot_src` is required now if you want to have the sysroot
    source libraries be loaded. I think we used to infer it as
    `{sysroot}/lib/rustlib/src/rust/library` before when only the
    `sysroot` field was given but that was since changed to make it
    possible in having a sysroot without the standard library sources
    (that is only have the binaries available). So if you want the
    library sources to be loaded by rust-analyzer you will have to set
    that field as well now.

  - Miguel ]

Link: https://github.com/rust-lang/rust-analyzer/pull/17287 [1]
Link: https://github.com/rust-lang/rust-analyzer/blob/f372a8a1176ff8dd5f45ab2ddd45f3530db0374f/crates/project-model/src/workspace.rs#L367-L374 [2]
Link: https://github.com/rust-lang/rust-analyzer/blob/eeb192b79aeac47b40add66347022af17a74fbaf/crates/project-model/src/sysroot.rs#L180-L192 [3]
Link: https://github.com/search?q=repo%3AVeykril%2Frust-analyzer%20src_root()&type=code

 [4]
Tested-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Sarthak Singh <sarthak.singh99@gmail.com>
Link: https://rust-for-linux.zulipchat.com/#narrow/stream/291565-Help/topic/How.20to.20rust-analyzer.20correctly.20working
Link: https://lore.kernel.org/r/20240724172713.899399-1-sarthak.singh99@gmail.com


[ Formatted comment, fixed typo and removed spurious empty line. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Switch away from our fork of the `alloc` crate. We remove it altogether
in the next commit.

Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20240328013603.206764-4-wedsonaf@gmail.com


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Both `core` and `alloc` have their `cfgs` (such as `no_rc`) missing
in `rust-project.json`.

To remedy this, pass the flags to `generate_rust_analyzer.py` for
them to be added to a dictionary where each key corresponds to
a crate and each value to a list of `cfg`s. The dictionary is then
used to pass the `cfg`s to each crate in the generated file (for
`core` and `alloc` only).

Signed-off-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://lore.kernel.org/r/20230804171448.54976-1-yakoyoku@gmail.com


[ Removed `Suggested-by` as discussed in mailing list. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Adds support for out-of-tree rust modules to use the `rust-analyzer`
make target to generate the rust-project.json file.

The change involves adding an optional parameter `external_src` to the
`generate_rust_analyzer.py` which expects the path to the out-of-tree
module's source directory. When this parameter is passed, I have chosen
not to add the non-core modules (samples and drivers) into the result
since these are not expected to be used in third party modules. Related
changes are also made to the Makefile and rust/Makefile allowing the
`rust-analyzer` target to be used for out-of-tree modules as well.

Link: https://github.com/Rust-for-Linux/linux/pull/914
Link: https://github.com/Rust-for-Linux/rust-out-of-tree-module/pull/2


Signed-off-by: Vinay Varma <varmavinaym@gmail.com>
Link: https://lore.kernel.org/r/20230411091714.130525-1-varmavinaym@gmail.com


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

More complex drivers might want to use modules to organize their Rust
code, but those module folders do not need a Makefile.
generate_rust_analyzer.py currently crashes on those. Fix it so that a
missing Makefile is silently ignored.

Link: https://github.com/Rust-for-Linux/linux/pull/883


Signed-off-by: Asahi Lina <lina@asahilina.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The `build_error` crate provides a function `build_error` which
will panic at compile-time if executed in const context and,
by default, will cause a build error if not executed at compile
time and the optimizer does not optimise away the call.

The `CONFIG_RUST_BUILD_ASSERT_ALLOW` kernel option allows to
relax the default build failure and convert it to a runtime
check. If the runtime check fails, `panic!` will be called.

Its functionality will be exposed to users as a couple macros in
the `kernel` crate in the following patch, thus some documentation
here refers to them for simplicity.

Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
[Reworded, adapted for upstream and applied latest changes]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The `generate_rust_analyzer.py` script generates the configuration
file (`rust-project.json`) for rust-analyzer.

rust-analyzer is a modular compiler frontend for the Rust language.
It provides an LSP server which can be used in editors such as
VS Code, Emacs or Vim.

Reviewed-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Signed-off-by: Boris-Chengbiao Zhou <bobo1239@web.de>
Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>