include/asm/compiler.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef __ASM_COMPILER_H
0003 #define __ASM_COMPILER_H
0004
0005 #ifdef ARM64_ASM_ARCH
0006 #define ARM64_ASM_PREAMBLE ".arch " ARM64_ASM_ARCH "\n"
0007 #else
0008 #define ARM64_ASM_PREAMBLE
0009 #endif
0010
0011 /*
0012  * The EL0/EL1 pointer bits used by a pointer authentication code.
0013  * This is dependent on TBI0/TBI1 being enabled, or bits 63:56 would also apply.
0014  */
0015 #define ptrauth_user_pac_mask()     GENMASK_ULL(54, vabits_actual)
0016 #define ptrauth_kernel_pac_mask()   GENMASK_ULL(63, vabits_actual)
0017
0018 /* Valid for EL0 TTBR0 and EL1 TTBR1 instruction pointers */
0019 #define ptrauth_clear_pac(ptr)                      \
0020     ((ptr & BIT_ULL(55)) ? (ptr | ptrauth_kernel_pac_mask()) :  \
0021                    (ptr & ~ptrauth_user_pac_mask()))
0022
0023 #define __builtin_return_address(val)                   \
0024     (void *)(ptrauth_clear_pac((unsigned long)__builtin_return_address(val)))
0025
0026 #endif /* __ASM_COMPILER_H */