[PATCH v5 03/20] x86/kexec: Use named labels in swap_pages in relocate_kernel_64.S

From: David Woodhouse
Date: Thu Dec 05 2024 - 10:34:59 EST


From: David Woodhouse <dwmw@xxxxxxxxxxxx>

Make the code a little more readable.

Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Acked-by: Kai Huang <kai.huang@xxxxxxxxx>
---
arch/x86/kernel/relocate_kernel_64.S | 30 ++++++++++++++--------------
1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
index 92478e2e254f..fea650f92606 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S
@@ -279,31 +279,31 @@ SYM_CODE_START_LOCAL_NOALIGN(swap_pages)
movq %rdi, %rcx /* Put the indirection_page in %rcx */
xorl %edi, %edi
xorl %esi, %esi
- jmp 1f
+ jmp .Lstart /* Should start with an indirection record */

-0: /* top, read another word for the indirection page */
+.Lloop: /* top, read another word for the indirection page */

movq (%rbx), %rcx
addq $8, %rbx
-1:
+.Lstart:
testb $0x1, %cl /* is it a destination page? */
- jz 2f
+ jz .Lnotdest
movq %rcx, %rdi
andq $0xfffffffffffff000, %rdi
- jmp 0b
-2:
+ jmp .Lloop
+.Lnotdest:
testb $0x2, %cl /* is it an indirection page? */
- jz 2f
+ jz .Lnotind
movq %rcx, %rbx
andq $0xfffffffffffff000, %rbx
- jmp 0b
-2:
+ jmp .Lloop
+.Lnotind:
testb $0x4, %cl /* is it the done indicator? */
- jz 2f
- jmp 3f
-2:
+ jz .Lnotdone
+ jmp .Ldone
+.Lnotdone:
testb $0x8, %cl /* is it the source indicator? */
- jz 0b /* Ignore it otherwise */
+ jz .Lloop /* Ignore it otherwise */
movq %rcx, %rsi /* For ever source page do a copy */
andq $0xfffffffffffff000, %rsi

@@ -328,8 +328,8 @@ SYM_CODE_START_LOCAL_NOALIGN(swap_pages)
rep ; movsq

lea PAGE_SIZE(%rax), %rsi
- jmp 0b
-3:
+ jmp .Lloop
+.Ldone:
ANNOTATE_UNRET_SAFE
ret
int3
--
2.47.0