/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_S390_JUMP_LABEL_H #define _ASM_S390_JUMP_LABEL_H #define HAVE_JUMP_LABEL_BATCH #ifndef __ASSEMBLY__ #include <linux/types.h> #include <linux/stringify.h> #define JUMP_LABEL_NOP_SIZE 6 #ifdef CONFIG_CC_IS_CLANG #define JUMP_LABEL_STATIC_KEY_CONSTRAINT "i" #elif __GNUC__ < 9 #define JUMP_LABEL_STATIC_KEY_CONSTRAINT "X" #else #define JUMP_LABEL_STATIC_KEY_CONSTRAINT "jdd" #endif /* * We use a brcl 0,<offset> instruction for jump labels so it * can be easily distinguished from a hotpatch generated instruction. */ static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { asm_volatile_goto("0: brcl 0,%l[label]\n" ".pushsection __jump_table,\"aw\"\n" ".balign 8\n" ".long 0b-.,%l[label]-.\n" ".quad %0+%1-.\n" ".popsection\n" : : JUMP_LABEL_STATIC_KEY_CONSTRAINT (key), "i" (branch) : : label); return false; label: return true; } static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch) { asm_volatile_goto("0: brcl 15,%l[label]\n" ".pushsection __jump_table,\"aw\"\n" ".balign 8\n" ".long 0b-.,%l[label]-.\n" ".quad %0+%1-.\n" ".popsection\n" : : JUMP_LABEL_STATIC_KEY_CONSTRAINT (key), "i" (branch) : : label); return false; label: return true; } #endif /* __ASSEMBLY__ */ #endif