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-rw-r--r--arch/x86/power/hibernate_asm_32.S85
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/x86/power/hibernate_asm_32.S b/arch/x86/power/hibernate_asm_32.S
new file mode 100644
index 000000000..6e56815e1
--- /dev/null
+++ b/arch/x86/power/hibernate_asm_32.S
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This may not use any stack, nor any variable that is not "NoSave":
+ *
+ * Its rewriting one kernel image with another. What is stack in "old"
+ * image could very well be data page in "new" image, and overwriting
+ * your own stack under you is bad idea.
+ */
+
+#include <linux/linkage.h>
+#include <asm/segment.h>
+#include <asm/page_types.h>
+#include <asm/asm-offsets.h>
+#include <asm/processor-flags.h>
+
+.text
+
+ENTRY(swsusp_arch_suspend)
+ movl %esp, saved_context_esp
+ movl %ebx, saved_context_ebx
+ movl %ebp, saved_context_ebp
+ movl %esi, saved_context_esi
+ movl %edi, saved_context_edi
+ pushfl
+ popl saved_context_eflags
+
+ call swsusp_save
+ ret
+
+ENTRY(restore_image)
+ movl mmu_cr4_features, %ecx
+ movl resume_pg_dir, %eax
+ subl $__PAGE_OFFSET, %eax
+ movl %eax, %cr3
+
+ jecxz 1f # cr4 Pentium and higher, skip if zero
+ andl $~(X86_CR4_PGE), %ecx
+ movl %ecx, %cr4; # turn off PGE
+ movl %cr3, %eax; # flush TLB
+ movl %eax, %cr3
+1:
+ movl restore_pblist, %edx
+ .p2align 4,,7
+
+copy_loop:
+ testl %edx, %edx
+ jz done
+
+ movl pbe_address(%edx), %esi
+ movl pbe_orig_address(%edx), %edi
+
+ movl $1024, %ecx
+ rep
+ movsl
+
+ movl pbe_next(%edx), %edx
+ jmp copy_loop
+ .p2align 4,,7
+
+done:
+ /* go back to the original page tables */
+ movl $swapper_pg_dir, %eax
+ subl $__PAGE_OFFSET, %eax
+ movl %eax, %cr3
+ movl mmu_cr4_features, %ecx
+ jecxz 1f # cr4 Pentium and higher, skip if zero
+ movl %ecx, %cr4; # turn PGE back on
+1:
+
+ movl saved_context_esp, %esp
+ movl saved_context_ebp, %ebp
+ movl saved_context_ebx, %ebx
+ movl saved_context_esi, %esi
+ movl saved_context_edi, %edi
+
+ pushl saved_context_eflags
+ popfl
+
+ /* Saved in save_processor_state. */
+ movl $saved_context, %eax
+ lgdt saved_context_gdt_desc(%eax)
+
+ xorl %eax, %eax
+
+ ret