| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _LINUX_INDIRECT_CALL_WRAPPER_H |
| #define _LINUX_INDIRECT_CALL_WRAPPER_H |
| |
| #ifdef CONFIG_RETPOLINE |
| |
| /* |
| * INDIRECT_CALL_$NR - wrapper for indirect calls with $NR known builtin |
| * @f: function pointer |
| * @f$NR: builtin functions names, up to $NR of them |
| * @__VA_ARGS__: arguments for @f |
| * |
| * Avoid retpoline overhead for known builtin, checking @f vs each of them and |
| * eventually invoking directly the builtin function. The functions are check |
| * in the given order. Fallback to the indirect call. |
| */ |
| #define INDIRECT_CALL_1(f, f1, ...) \ |
| ({ \ |
| likely(f == f1) ? f1(__VA_ARGS__) : f(__VA_ARGS__); \ |
| }) |
| #define INDIRECT_CALL_2(f, f2, f1, ...) \ |
| ({ \ |
| likely(f == f2) ? f2(__VA_ARGS__) : \ |
| INDIRECT_CALL_1(f, f1, __VA_ARGS__); \ |
| }) |
| #define INDIRECT_CALL_3(f, f3, f2, f1, ...) \ |
| ({ \ |
| likely(f == f3) ? f3(__VA_ARGS__) : \ |
| INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__); \ |
| }) |
| #define INDIRECT_CALL_4(f, f4, f3, f2, f1, ...) \ |
| ({ \ |
| likely(f == f4) ? f4(__VA_ARGS__) : \ |
| INDIRECT_CALL_3(f, f3, f2, f1, __VA_ARGS__); \ |
| }) |
| |
| #define INDIRECT_CALLABLE_DECLARE(f) f |
| #define INDIRECT_CALLABLE_SCOPE |
| #define EXPORT_INDIRECT_CALLABLE(f) EXPORT_SYMBOL(f) |
| |
| #else |
| #define INDIRECT_CALL_1(f, f1, ...) f(__VA_ARGS__) |
| #define INDIRECT_CALL_2(f, f2, f1, ...) f(__VA_ARGS__) |
| #define INDIRECT_CALL_3(f, f3, f2, f1, ...) f(__VA_ARGS__) |
| #define INDIRECT_CALL_4(f, f4, f3, f2, f1, ...) f(__VA_ARGS__) |
| #define INDIRECT_CALLABLE_DECLARE(f) |
| #define INDIRECT_CALLABLE_SCOPE static |
| #define EXPORT_INDIRECT_CALLABLE(f) |
| #endif |
| |
| /* |
| * We can use INDIRECT_CALL_$NR for ipv6 related functions only if ipv6 is |
| * builtin, this macro simplify dealing with indirect calls with only ipv4/ipv6 |
| * alternatives |
| */ |
| #if IS_BUILTIN(CONFIG_IPV6) |
| #define INDIRECT_CALL_INET(f, f2, f1, ...) \ |
| INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__) |
| #elif IS_ENABLED(CONFIG_INET) |
| #define INDIRECT_CALL_INET(f, f2, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__) |
| #else |
| #define INDIRECT_CALL_INET(f, f2, f1, ...) f(__VA_ARGS__) |
| #endif |
| |
| #if IS_ENABLED(CONFIG_INET) |
| #define INDIRECT_CALL_INET_1(f, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__) |
| #else |
| #define INDIRECT_CALL_INET_1(f, f1, ...) f(__VA_ARGS__) |
| #endif |
| |
| #endif |