Andreas Hindborg <nmi@xxxxxxxxxxxx> writes: > Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx> writes: > >> On Thu, Mar 14, 2024 at 9:58 AM Andreas Hindborg <nmi@xxxxxxxxxxxx> wrote: >>> >>> Yes, good point. Another option suggested by Miguel is that >>> `__blk_mq_free_request` need not be exported at all. We can make it >>> non-static and then call it from >>> `rust_helper_blk_mq_free_request_internal()`. Then only the latter will >>> be in the kernel image symbol table, which might be better in terms of >>> not exposing `__blk_mq_free_request()` directly. >> >> The helper is not needed, i.e. what I meant was to make it non-static >> and add it to `include/linux/blk-mq.h`. > > The way the current code compiles, <kernel::block::mq::Request as > kernel::types::AlwaysRefCounted>::dec_ref` is inlined into the `rnull` > module. A relocation for `rust_helper_blk_mq_free_request_internal` > appears in `rnull_mod.ko`. I didn't test it yet, but if > `__blk_mq_free_request` (or the helper) is not exported, I don't think > this would be possible? > I just tested what you suggested Miguel, and I get a link error for `__blk_mq_free_request` being undefined when the module is linked. This is even though the code that calls this function lives in the `kernel` crate, because it is inlined. BR Andreas
