jump_label.h

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2#ifndef _ASM_POWERPC_JUMP_LABEL_H
 3#define _ASM_POWERPC_JUMP_LABEL_H
 4
 5/*
 6 * Copyright 2010 Michael Ellerman, IBM Corp.
 7 */
 8
 9#ifndef __ASSEMBLER__
10#include <linux/types.h>
11
12#include <asm/feature-fixups.h>
13#include <asm/asm-const.h>
14
15#define JUMP_ENTRY_TYPE		stringify_in_c(FTR_ENTRY_LONG)
16#define JUMP_LABEL_NOP_SIZE	4
17
18static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
19{
20	asm goto("1:\n\t"
21		 "nop # arch_static_branch\n\t"
22		 ".pushsection __jump_table,  \"aw\"\n\t"
23		 ".long 1b - ., %l[l_yes] - .\n\t"
24		 JUMP_ENTRY_TYPE "%c0 - .\n\t"
25		 ".popsection \n\t"
26		 : :  "i" (&((char *)key)[branch]) : : l_yes);
27
28	return false;
29l_yes:
30	return true;
31}
32
33static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
34{
35	asm goto("1:\n\t"
36		 "b %l[l_yes] # arch_static_branch_jump\n\t"
37		 ".pushsection __jump_table,  \"aw\"\n\t"
38		 ".long 1b - ., %l[l_yes] - .\n\t"
39		 JUMP_ENTRY_TYPE "%c0 - .\n\t"
40		 ".popsection \n\t"
41		 : :  "i" (&((char *)key)[branch]) : : l_yes);
42
43	return false;
44l_yes:
45	return true;
46}
47
48#else
49#define ARCH_STATIC_BRANCH(LABEL, KEY)		\
501098:	nop;					\
51	.pushsection __jump_table, "aw";	\
52	.long 1098b - ., LABEL - .;		\
53	FTR_ENTRY_LONG KEY - .;			\
54	.popsection
55#endif
56
57#endif /* _ASM_POWERPC_JUMP_LABEL_H */