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 */ 23