arch/csky/include/asm/vdso.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef __ASM_CSKY_VDSO_H
   4 #define __ASM_CSKY_VDSO_H
   5
   6 #include <linux/types.h>
   7
   8 /*
   9  * The VDSO symbols are mapped into Linux so we can just use regular symbol
  10  * addressing to get their offsets in userspace.  The symbols are mapped at an
  11  * offset of 0, but since the linker must support setting weak undefined
  12  * symbols to the absolute address 0 it also happens to support other low
  13  * addresses even when the code model suggests those low addresses would not
  14  * otherwise be available.
  15  */
  16 #define VDSO_SYMBOL(base, name)                                                 \
  17 ({                                                                              \
  18         extern const char __vdso_##name[];                                      \
  19         (void __user *)((unsigned long)(base) + __vdso_##name);                 \
  20 })
  21
  22 #endif /* __ASM_CSKY_VDSO_H */