[PATCH v4 1/2] rust: move EXPORT_SYMBOL_RUST_GPL to include/linux/export.h

[Giuliano Procida <gprocida@google.com>]

Move identical definitions of `EXPORT_SYMBOL_RUST_GPL` to
`include/linux/export.h` from:

- `rust/exports.c`
- `drivers/gpu/nova-core/nova_core_exports.c`

Both files already include `<linux/export.h>`.

Update `scripts/misc-check` to recognize `EXPORT_SYMBOL_RUST_GPL()` and
reference it in `nova_core_exports.c`'s header comment so `W=2` builds
do not warn about an unused `<linux/export.h>` include.

Signed-off-by: Giuliano Procida <gprocida@google.com>
---
 drivers/gpu/nova-core/nova_core_exports.c |  5 ++---
 include/linux/export.h                    | 13 +++++++++++++
 rust/exports.c                            | 12 +-----------
 scripts/misc-check                        |  4 ++--
 4 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/nova-core/nova_core_exports.c b/drivers/gpu/nova-core/nova_core_exports.c
index 6e80ca9792ee..51858f376c7b 100644
--- a/drivers/gpu/nova-core/nova_core_exports.c
+++ b/drivers/gpu/nova-core/nova_core_exports.c
@@ -2,7 +2,8 @@
 // SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 
 /*
- * Exports Rust symbols from the `nova_core` crate for use by dependent modules.
+ * Exports Rust symbols from the `nova_core` crate for use by dependent modules
+ * via `EXPORT_SYMBOL_RUST_GPL()`.
  *
  * This is a workaround until the build system supports Rust cross-module
  * dependencies natively.
@@ -10,6 +11,4 @@
 
 #include <linux/export.h>
 
-#define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym)
-
 #include "exports_nova_core_generated.h"
diff --git a/include/linux/export.h b/include/linux/export.h
index a686fd0ba406..4aeb422d86af 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -93,4 +93,17 @@
 
 #define EXPORT_SYMBOL_FOR_MODULES(sym, mods) __EXPORT_SYMBOL(sym, "GPL", "module:" mods)
 
+/*
+ * A hack to export Rust symbols for loadable modules without having to redo
+ * the entire `EXPORT_SYMBOL_GPL` logic in Rust.
+ *
+ * This requires Rust's new/future `v0` mangling scheme because the default one
+ * ("legacy") uses invalid characters for C identifiers (thus we cannot use the
+ * `EXPORT_SYMBOL_*` macros).
+ *
+ * All symbols are exported as GPL-only to guarantee no GPL-only feature is
+ * accidentally exposed.
+ */
+#define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym)
+
 #endif /* _LINUX_EXPORT_H */
diff --git a/rust/exports.c b/rust/exports.c
index 1b52460b0f4e..8b2dd4aa1f92 100644
--- a/rust/exports.c
+++ b/rust/exports.c
@@ -1,20 +1,10 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * A hack to export Rust symbols for loadable modules without having to redo
- * the entire `include/linux/export.h` logic in Rust.
- *
- * This requires Rust's new/future `v0` mangling scheme because the default one
- * ("legacy") uses invalid characters for C identifiers (thus we cannot use the
- * `EXPORT_SYMBOL_*` macros).
- *
- * All symbols are exported as GPL-only to guarantee no GPL-only feature is
- * accidentally exposed.
+ * Export symbols from the `rust/` crates and C helpers for loadable modules.
  */
 
 #include <linux/export.h>
 
-#define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym)
-
 #include "exports_core_generated.h"
 #include "exports_bindings_generated.h"
 #include "exports_kernel_generated.h"
diff --git a/scripts/misc-check b/scripts/misc-check
index 40e5a4b01ff4..bb30247f93de 100755
--- a/scripts/misc-check
+++ b/scripts/misc-check
@@ -45,7 +45,7 @@ check_tracked_ignored_files () {
 # does not automatically fix it.
 check_missing_include_linux_export_h () {
 
-	git -C "${srctree:-.}" grep --files-with-matches -E 'EXPORT_SYMBOL((_NS)?(_GPL)?|_FOR_MODULES)\(.*\)' \
+	git -C "${srctree:-.}" grep --files-with-matches -E 'EXPORT_SYMBOL((_NS)?(_GPL)?|_FOR_MODULES|_RUST_GPL)\(.*\)' \
 	    -- '*.[ch]' :^tools/ :^include/linux/export.h |
 	xargs -r git -C "${srctree:-.}" grep --files-without-match '#include[[:space:]]*<linux/export\.h>' |
 	xargs -r printf "%s: warning: EXPORT_SYMBOL() is used, but #include <linux/export.h> is missing\n" >&2
@@ -58,7 +58,7 @@ check_unnecessary_include_linux_export_h () {
 
 	git -C "${srctree:-.}" grep --files-with-matches '#include[[:space:]]*<linux/export\.h>' \
 	    -- '*.[c]' :^tools/ |
-	xargs -r git -C "${srctree:-.}" grep --files-without-match -E 'EXPORT_SYMBOL((_NS)?(_GPL)?|_FOR_MODULES)\(.*\)' |
+	xargs -r git -C "${srctree:-.}" grep --files-without-match -E 'EXPORT_SYMBOL((_NS)?(_GPL)?|_FOR_MODULES|_RUST_GPL)\(.*\)' |
 	xargs -r printf "%s: warning: EXPORT_SYMBOL() is not used, but #include <linux/export.h> is present\n" >&2
 }
 
-- 
2.56.0.385.gac671c819a-goog