1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _ASM_X86_JUMP_LABEL_H |
3 | #define _ASM_X86_JUMP_LABEL_H |
4 | |
5 | #define JUMP_LABEL_NOP_SIZE 5 |
6 | |
7 | #ifdef CONFIG_X86_64 |
8 | # define STATIC_KEY_INIT_NOP P6_NOP5_ATOMIC |
9 | #else |
10 | # define STATIC_KEY_INIT_NOP GENERIC_NOP5_ATOMIC |
11 | #endif |
12 | |
13 | #include <asm/asm.h> |
14 | #include <asm/nops.h> |
15 | |
16 | #ifndef __ASSEMBLY__ |
17 | |
18 | #include <linux/stringify.h> |
19 | #include <linux/types.h> |
20 | |
21 | static __always_inline bool arch_static_branch(struct static_key *key, bool branch) |
22 | { |
23 | asm_volatile_goto("1:" |
24 | ".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t" |
25 | ".pushsection __jump_table, \"aw\" \n\t" |
26 | _ASM_ALIGN "\n\t" |
27 | ".long 1b - ., %l[l_yes] - . \n\t" |
28 | _ASM_PTR "%c0 + %c1 - .\n\t" |
29 | ".popsection \n\t" |
30 | : : "i" (key), "i" (branch) : : l_yes); |
31 | |
32 | return false; |
33 | l_yes: |
34 | return true; |
35 | } |
36 | |
37 | static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch) |
38 | { |
39 | asm_volatile_goto("1:" |
40 | ".byte 0xe9\n\t .long %l[l_yes] - 2f\n\t" |
41 | "2:\n\t" |
42 | ".pushsection __jump_table, \"aw\" \n\t" |
43 | _ASM_ALIGN "\n\t" |
44 | ".long 1b - ., %l[l_yes] - . \n\t" |
45 | _ASM_PTR "%c0 + %c1 - .\n\t" |
46 | ".popsection \n\t" |
47 | : : "i" (key), "i" (branch) : : l_yes); |
48 | |
49 | return false; |
50 | l_yes: |
51 | return true; |
52 | } |
53 | |
54 | #else /* __ASSEMBLY__ */ |
55 | |
56 | .macro STATIC_JUMP_IF_TRUE target, key, def |
57 | .Lstatic_jump_\@: |
58 | .if \def |
59 | /* Equivalent to "jmp.d32 \target" */ |
60 | .byte 0xe9 |
61 | .long \target - .Lstatic_jump_after_\@ |
62 | .Lstatic_jump_after_\@: |
63 | .else |
64 | .byte STATIC_KEY_INIT_NOP |
65 | .endif |
66 | .pushsection __jump_table, "aw" |
67 | _ASM_ALIGN |
68 | .long .Lstatic_jump_\@ - ., \target - . |
69 | _ASM_PTR \key - . |
70 | .popsection |
71 | .endm |
72 | |
73 | .macro STATIC_JUMP_IF_FALSE target, key, def |
74 | .Lstatic_jump_\@: |
75 | .if \def |
76 | .byte STATIC_KEY_INIT_NOP |
77 | .else |
78 | /* Equivalent to "jmp.d32 \target" */ |
79 | .byte 0xe9 |
80 | .long \target - .Lstatic_jump_after_\@ |
81 | .Lstatic_jump_after_\@: |
82 | .endif |
83 | .pushsection __jump_table, "aw" |
84 | _ASM_ALIGN |
85 | .long .Lstatic_jump_\@ - ., \target - . |
86 | _ASM_PTR \key + 1 - . |
87 | .popsection |
88 | .endm |
89 | |
90 | #endif /* __ASSEMBLY__ */ |
91 | |
92 | #endif |
93 | |