rust: kbuild: auto generate helper exports

This removes the need to explicitly export all symbols.

Generate helper exports similarly to what's currently done for Rust
crates. These helpers are exclusively called from within Rust code and
therefore can be treated similar as other Rust symbols.

Signed-off-by: Gary Guo <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Tested-by: Boqun Feng <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Fixed dependency path, reworded slightly, edited comment a bit and
  rebased on top of the changes made when applying Andreas' patch
  (e.g. no `README.md` anymore, so moved the edits).  - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

1 files changed, 0 insertions, 3 deletions

diff --git a/rust/helpers/page.c b/rust/helpers/page.c
index 7fd333411a88..b3f2b8fbf87f 100644
--- a/rust/helpers/page.c
+++ b/rust/helpers/page.c
@@ -7,16 +7,13 @@ struct page *rust_helper_alloc_pages(gfp_t gfp_mask, unsigned int order)
 {
 	return alloc_pages(gfp_mask, order);
 }
-EXPORT_SYMBOL_GPL(rust_helper_alloc_pages);
 
 void *rust_helper_kmap_local_page(struct page *page)
 {
 	return kmap_local_page(page);
 }
-EXPORT_SYMBOL_GPL(rust_helper_kmap_local_page);
 
 void rust_helper_kunmap_local(const void *addr)
 {
 	kunmap_local(addr);
 }
-EXPORT_SYMBOL_GPL(rust_helper_kunmap_local);