[PATCH 4/5] x86: jump_label: switch to jump_entry accessors
From: Ard Biesheuvel
Date: Wed Jun 27 2018 - 12:06:23 EST
In preparation of switching x86 to use place-relative references for
the code, target and key members of struct jump_entry, replace direct
references to the struct members with invocations of the new accessors.
This will allow us to make the switch by modifying the accessors only.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
---
arch/x86/kernel/jump_label.c | 43 ++++++++++++--------
1 file changed, 26 insertions(+), 17 deletions(-)
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index e56c95be2808..d64296092ef5 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -52,22 +52,24 @@ static void __jump_label_transform(struct jump_entry *entry,
* Jump label is enabled for the first time.
* So we expect a default_nop...
*/
- if (unlikely(memcmp((void *)entry->code, default_nop, 5)
- != 0))
- bug_at((void *)entry->code, __LINE__);
+ if (unlikely(memcmp((void *)jump_entry_code(entry),
+ default_nop, 5) != 0))
+ bug_at((void *)jump_entry_code(entry),
+ __LINE__);
} else {
/*
* ...otherwise expect an ideal_nop. Otherwise
* something went horribly wrong.
*/
- if (unlikely(memcmp((void *)entry->code, ideal_nop, 5)
- != 0))
- bug_at((void *)entry->code, __LINE__);
+ if (unlikely(memcmp((void *)jump_entry_code(entry),
+ ideal_nop, 5) != 0))
+ bug_at((void *)jump_entry_code(entry),
+ __LINE__);
}
code.jump = 0xe9;
- code.offset = entry->target -
- (entry->code + JUMP_LABEL_NOP_SIZE);
+ code.offset = jump_entry_target(entry) -
+ (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
} else {
/*
* We are disabling this jump label. If it is not what
@@ -76,14 +78,18 @@ static void __jump_label_transform(struct jump_entry *entry,
* are converting the default nop to the ideal nop.
*/
if (init) {
- if (unlikely(memcmp((void *)entry->code, default_nop, 5) != 0))
- bug_at((void *)entry->code, __LINE__);
+ if (unlikely(memcmp((void *)jump_entry_code(entry),
+ default_nop, 5) != 0))
+ bug_at((void *)jump_entry_code(entry),
+ __LINE__);
} else {
code.jump = 0xe9;
- code.offset = entry->target -
- (entry->code + JUMP_LABEL_NOP_SIZE);
- if (unlikely(memcmp((void *)entry->code, &code, 5) != 0))
- bug_at((void *)entry->code, __LINE__);
+ code.offset = jump_entry_target(entry) -
+ (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
+ if (unlikely(memcmp((void *)jump_entry_code(entry),
+ &code, 5) != 0))
+ bug_at((void *)jump_entry_code(entry),
+ __LINE__);
}
memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE);
}
@@ -97,10 +103,13 @@ static void __jump_label_transform(struct jump_entry *entry,
*
*/
if (poker)
- (*poker)((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE);
+ (*poker)((void *)jump_entry_code(entry), &code,
+ JUMP_LABEL_NOP_SIZE);
else
- text_poke_bp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE,
- (void *)entry->code + JUMP_LABEL_NOP_SIZE);
+ text_poke_bp((void *)jump_entry_code(entry), &code,
+ JUMP_LABEL_NOP_SIZE,
+ (void *)jump_entry_code(entry) +
+ JUMP_LABEL_NOP_SIZE);
}
void arch_jump_label_transform(struct jump_entry *entry,
--
2.11.0