/* 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 #include #include #include #include #include .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 FRAME_BEGIN call swsusp_save FRAME_END ret ENDPROC(swsusp_arch_suspend) 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: /* code below belongs to the image kernel */ .align PAGE_SIZE ENTRY(restore_registers) /* 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 ENDPROC(restore_registers)