Convert most use sites from `co_return coroutine::make_exception`
to `co_await coroutine::return_exception{,_ptr}` where possible.
In cases this is done in a catch clause, convert to
`co_return coroutine::exception`, generating an exception_ptr
if needed.
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Closes#10972
To call a UDF that is using WASI, we need to properly
configure the wasmtime instance that it will be called
on. The configuration was missing from udf_cache::load(),
so we add it here.
The free function does not return any value, so we should use
a calling method that does not expect any returns.
This patch adds such a method and uses it.
A test that did not pass without this fix and does pass after
is added.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Closes#10935
After previous patch hints manager class gets unused dependency on
snitch. While removing it it turns out that several unrelated places
get needed headers indirectly via host_filter.hh -> snitsh_base.hh
inclusion.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Because the only available version of wasm ABI did not allow
freeing any allocated memory, a new version of the ABI is
introduced. In this version, the host is required to export
_scylla_malloc and _scylla_free methods, which are later used
for the memory management.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
One of the issues that comes with compiling programs to WebAssembly
is the lack of a default implementation of a memory allocator. As
a result, the only available solutions to the need of memory allocation
are growing the wasm memory for each new allocated segment, or
implementing one's own memory allocator. To avoid both of these
approaches, for many languages, the user may compile a program to
a WASI target. By doing so, the compiler adds default implementations
of malloc and free methods, and the user can use them for dynamic
memory management.
This patch enables executing programs compiled with WASI by enabling
it in the wasmtime runtime.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Different languages may require different ABIs for passing
parameters, etc. This patch adds a requirement for all wasm
UDFs to export an _scylla_abi symbol, that is an 32-bit integer
with a value specifying the ABI version.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
WebAssembly uses 32-bit address space, while also
having 64-bit integers as it native types. As a result,
when passing size of an object in memory and its address,
it can be combined into one 64-bit value. As a bonus,
if the object is null, we can signal it by passing -1 as
its size.
This patch implements handling of this new ABI and adjusts
expamples in test_wasm.py.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Both init_nullable_arg_visitor and, in case
of abstract_type, init_arg_visitor were
the same method with one difference. The
common part was moved to init_abstract_arg,
and the difference remained in the operator()
method.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
The memory.grow and memory.size wasm methods return
the memory size in pages, and memory.size takes its
argument in the number of pages. A WebAssembly page
has a size of 64KiB, so during memory allocation
we have to divide our desired size in bytes by page
size and round up. Similarly, when reading memory
size we need to multiply the result by 64KiB to
get the size in bytes.
The change affects current naive allocator for
arguments when calling wasm UDFs and the examples
in wasm_test.py - both commented code and compiled
wasm in text representation.
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
The wasm::engine exists as a sharded<> service in main, but it's only
passed by local reference into database on start. There's no much profit
in keeping it at main scope, things get much simpler if keeping the
engine purely on database.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The engine is based on wasmtime and is able to:
- compile wasm text format to bytecode
- run a given compiled function with custom arguments
This implementation is missing crucial features, like running
on any other types than 32-bit integers. It serves as a skeleton
for future full implementation.
