arch/riscv/include/asm/vdso.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2012 ARM Limited
   4  * Copyright (C) 2014 Regents of the University of California
   5  * Copyright (C) 2017 SiFive
   6  */
   7
   8 #ifndef _ASM_RISCV_VDSO_H
   9 #define _ASM_RISCV_VDSO_H
  10
  11 #include <linux/types.h>
  12
  13 struct vdso_data {
  14 };
  15
  16 /*
  17  * The VDSO symbols are mapped into Linux so we can just use regular symbol
  18  * addressing to get their offsets in userspace.  The symbols are mapped at an
  19  * offset of 0, but since the linker must support setting weak undefined
  20  * symbols to the absolute address 0 it also happens to support other low
  21  * addresses even when the code model suggests those low addresses would not
  22  * otherwise be availiable.
  23  */
  24 #define VDSO_SYMBOL(base, name)                                                 \
  25 ({                                                                              \
  26         extern const char __vdso_##name[];                                      \
  27         (void __user *)((unsigned long)(base) + __vdso_##name);                 \
  28 })
  29
  30 asmlinkage long sys_riscv_flush_icache(uintptr_t, uintptr_t, uintptr_t);
  31
  32 #endif /* _ASM_RISCV_VDSO_H */