; VMM - World Switchers, 32Bit to AMD64. ; ; ; Copyright (C) 2006-2007 Sun Microsystems, Inc. ; ; This file is part of VirtualBox Open Source Edition (OSE), as ; available from http://www.virtualbox.org. This file is free software; ; you can redistribute it and/or modify it under the terms of the GNU ; General Public License (GPL) as published by the Free Software ; Foundation, in version 2 as it comes in the "COPYING" file of the ; VirtualBox OSE distribution. VirtualBox OSE is distributed in the ; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. ; ; Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa ; Clara, CA 95054 USA or visit http://www.sun.com if you need ; additional information or have any questions. ; ;%define DEBUG_STUFF 1 ;%define STRICT_IF 1 ;******************************************************************************* ;* Defined Constants And Macros * ;******************************************************************************* ;******************************************************************************* ;* Header Files * ;******************************************************************************* %include "VBox/asmdefs.mac" %include "VBox/x86.mac" %include "VBox/cpum.mac" %include "VBox/stam.mac" %include "VBox/vm.mac" %include "CPUMInternal.mac" %include "VMMSwitcher/VMMSwitcher.mac" ; ; Start the fixup records ; We collect the fixups in the .data section as we go along ; It is therefore VITAL that no-one is using the .data section ; for anything else between 'Start' and 'End'. ; BEGINDATA GLOBALNAME Fixups BEGINCODE GLOBALNAME Start BITS 32 ;; ; The C interface. ; BEGINPROC vmmR0HostToGuest %ifdef DEBUG_STUFF COM32_S_NEWLINE COM32_S_CHAR '^' %endif %ifdef VBOX_WITH_STATISTICS ; ; Switcher stats. ; FIXUP FIX_HC_VM_OFF, 1, VM.StatSwitcherToGC mov edx, 0ffffffffh STAM_PROFILE_ADV_START edx %endif ; ; Call worker. ; FIXUP FIX_HC_CPUM_OFF, 1, 0 mov edx, 0ffffffffh push cs ; allow for far return and restore cs correctly. call NAME(vmmR0HostToGuestAsm) %ifdef VBOX_WITH_STATISTICS ; ; Switcher stats. ; FIXUP FIX_HC_VM_OFF, 1, VM.StatSwitcherToHC mov edx, 0ffffffffh STAM_PROFILE_ADV_STOP edx %endif ret ENDPROC vmmR0HostToGuest ; ***************************************************************************** ; vmmR0HostToGuestAsm ; ; Phase one of the switch from host to guest context (host MMU context) ; ; INPUT: ; - edx virtual address of CPUM structure (valid in host context) ; ; USES/DESTROYS: ; - eax, ecx, edx, esi ; ; ASSUMPTION: ; - current CS and DS selectors are wide open ; ; ***************************************************************************** ALIGNCODE(16) BEGINPROC vmmR0HostToGuestAsm ;; ;; Save CPU host context ;; Skip eax, edx and ecx as these are not preserved over calls. ;; CPUMCPU_FROM_CPUM(edx) ; general registers. mov [edx + CPUMCPU.Host.ebx], ebx mov [edx + CPUMCPU.Host.edi], edi mov [edx + CPUMCPU.Host.esi], esi mov [edx + CPUMCPU.Host.esp], esp mov [edx + CPUMCPU.Host.ebp], ebp ; selectors. mov [edx + CPUMCPU.Host.ds], ds mov [edx + CPUMCPU.Host.es], es mov [edx + CPUMCPU.Host.fs], fs mov [edx + CPUMCPU.Host.gs], gs mov [edx + CPUMCPU.Host.ss], ss ; special registers. sldt [edx + CPUMCPU.Host.ldtr] sidt [edx + CPUMCPU.Host.idtr] sgdt [edx + CPUMCPU.Host.gdtr] str [edx + CPUMCPU.Host.tr] ; flags pushfd pop dword [edx + CPUMCPU.Host.eflags] ;; handle use flags. mov esi, [edx + CPUMCPU.fUseFlags] ; esi == use flags. and esi, ~CPUM_USED_FPU ; Clear CPUM_USED_* flags. ;;@todo FPU check can be optimized to use cr0 flags! mov [edx + CPUMCPU.fUseFlags], esi ; control registers. mov eax, cr0 mov [edx + CPUMCPU.Host.cr0], eax ;Skip cr2; assume host os don't stuff things in cr2. (safe) mov eax, cr3 mov [edx + CPUMCPU.Host.cr3], eax mov eax, cr4 mov [edx + CPUMCPU.Host.cr4], eax CPUM_FROM_CPUMCPU(edx) ; Load new gdt so we can do far jump after going into 64 bits mode lgdt [edx + CPUM.Hyper.gdtr] ;; ;; Load Intermediate memory context. ;; FIXUP SWITCHER_FIX_INTER_CR3_HC, 1 mov eax, 0ffffffffh mov cr3, eax DEBUG_CHAR('?') ;; ;; Jump to identity mapped location ;; FIXUP FIX_HC_2_ID_NEAR_REL, 1, NAME(IDEnterTarget) - NAME(Start) jmp near NAME(IDEnterTarget) ; We're now on identity mapped pages! ALIGNCODE(16) GLOBALNAME IDEnterTarget DEBUG_CHAR('2') ; 1. Disable paging. mov ebx, cr0 and ebx, ~X86_CR0_PG mov cr0, ebx DEBUG_CHAR('2') ; 2. Enable PAE. mov ecx, cr4 or ecx, X86_CR4_PAE mov cr4, ecx ; 3. Load long mode intermediate CR3. FIXUP FIX_INTER_AMD64_CR3, 1 mov ecx, 0ffffffffh mov cr3, ecx DEBUG_CHAR('3') ; 4. Enable long mode. mov ebp, edx mov ecx, MSR_K6_EFER rdmsr or eax, MSR_K6_EFER_LME wrmsr mov edx, ebp DEBUG_CHAR('4') ; 5. Enable paging. or ebx, X86_CR0_PG mov cr0, ebx DEBUG_CHAR('5') ; Jump from compatability mode to 64-bit mode. FIXUP FIX_ID_FAR32_TO_64BIT_MODE, 1, NAME(IDEnter64Mode) - NAME(Start) jmp 0ffffh:0fffffffeh ; ; We're in 64-bit mode (ds, ss, es, fs, gs are all bogus). BITS 64 ALIGNCODE(16) NAME(IDEnter64Mode): DEBUG_CHAR('6') jmp [NAME(pICEnterTarget) wrt rip] ; 64-bit jump target NAME(pICEnterTarget): FIXUP FIX_HC_64BIT_NOCHECK, 0, NAME(ICEnterTarget) - NAME(Start) dq 0ffffffffffffffffh ; 64-bit pCpum address. NAME(pCpumIC): FIXUP FIX_HC_64BIT_CPUM, 0 dq 0ffffffffffffffffh ; ; When we arrive here we're in 64 bits mode in the intermediate context ; ALIGNCODE(16) GLOBALNAME ICEnterTarget ; at this moment we're in 64-bit mode. let's write something to CPUM ; Load CPUM pointer into rdx mov rdx, [NAME(pCpumIC) wrt rip] ; Load the CPUMCPU offset. mov r8, [rdx + CPUM.ulOffCPUMCPU] mov rsi, 012345678h mov [rdx + r8 + CPUMCPU.uPadding], rsi ; now let's switch back mov rax, 0666h jmp NAME(VMMGCGuestToHostAsm) ; rax = returncode. ENDPROC vmmR0HostToGuestAsm ;; ; Trampoline for doing a call when starting the hyper visor execution. ; ; Push any arguments to the routine. ; Push the argument frame size (cArg * 4). ; Push the call target (_cdecl convention). ; Push the address of this routine. ; ; BITS 64 ALIGNCODE(16) BEGINPROC vmmGCCallTrampoline %ifdef DEBUG_STUFF COM32_S_CHAR 'c' COM32_S_CHAR 't' COM32_S_CHAR '!' %endif int3 ENDPROC vmmGCCallTrampoline ;; ; The C interface. ; BITS 64 ALIGNCODE(16) BEGINPROC vmmGCGuestToHost %ifdef DEBUG_STUFF push esi COM_NEWLINE DEBUG_CHAR('b') DEBUG_CHAR('a') DEBUG_CHAR('c') DEBUG_CHAR('k') DEBUG_CHAR('!') COM_NEWLINE pop esi %endif int3 ENDPROC vmmGCGuestToHost ;; ; VMMGCGuestToHostAsm ; ; This is an alternative entry point which we'll be using ; when the we have saved the guest state already or we haven't ; been messing with the guest at all. ; ; @param eax Return code. ; @uses eax, edx, ecx (or it may use them in the future) ; BITS 64 ALIGNCODE(16) BEGINPROC VMMGCGuestToHostAsm CPUMCPU_FROM_CPUM(rdx) FIXUP FIX_INTER_AMD64_CR3, 1 mov rax, 0ffffffffh mov cr3, rax ;; We're now in the intermediate memory context! ;; ;; Switch to compatibility mode, placing ourselves in identity mapped code. ;; jmp far [NAME(fpIDEnterTarget) wrt rip] ; 16:32 Pointer to IDEnterTarget. NAME(fpIDEnterTarget): FIXUP FIX_ID_32BIT, 0, NAME(IDExitTarget) - NAME(Start) dd 0 FIXUP FIX_HYPER_CS, 0 dd 0 ; We're now on identity mapped pages! ALIGNCODE(16) GLOBALNAME IDExitTarget BITS 32 DEBUG_CHAR('1') ; 1. Deactivate long mode by turning off paging. mov ebx, cr0 and ebx, ~X86_CR0_PG mov cr0, ebx DEBUG_CHAR('2') ; 2. Load intermediate page table. FIXUP SWITCHER_FIX_INTER_CR3_HC, 1 mov edx, 0ffffffffh mov cr3, edx DEBUG_CHAR('3') ; 3. Disable long mode. mov ecx, MSR_K6_EFER rdmsr DEBUG_CHAR('5') and eax, ~(MSR_K6_EFER_LME) wrmsr DEBUG_CHAR('6') %ifndef NEED_PAE_ON_HOST ; 3b. Disable PAE. mov eax, cr4 and eax, ~X86_CR4_PAE mov cr4, eax DEBUG_CHAR('7') %endif ; 4. Enable paging. or ebx, X86_CR0_PG mov cr0, ebx jmp short just_a_jump just_a_jump: DEBUG_CHAR('8') ;; ;; 5. Jump to guest code mapping of the code and load the Hypervisor CS. ;; FIXUP FIX_ID_2_HC_NEAR_REL, 1, NAME(ICExitTarget) - NAME(Start) jmp near NAME(ICExitTarget) ;; ;; When we arrive at this label we're at the ;; intermediate mapping of the switching code. ;; BITS 32 ALIGNCODE(16) GLOBALNAME ICExitTarget DEBUG_CHAR('8') FIXUP FIX_HC_CPUM_OFF, 1, 0 mov edx, 0ffffffffh CPUMCPU_FROM_CPUM(edx) mov esi, [edx + CPUMCPU.Host.cr3] mov cr3, esi ;; now we're in host memory context, let's restore regs ; activate host gdt and idt lgdt [edx + CPUMCPU.Host.gdtr] DEBUG_CHAR('0') lidt [edx + CPUMCPU.Host.idtr] DEBUG_CHAR('1') ; Restore TSS selector; must mark it as not busy before using ltr (!) ; ASSUME that this is supposed to be 'BUSY'. (saves 20-30 ticks on the T42p) movzx eax, word [edx + CPUMCPU.Host.tr] ; eax <- TR and al, 0F8h ; mask away TI and RPL bits, get descriptor offset. add eax, [edx + CPUMCPU.Host.gdtr + 2] ; eax <- GDTR.address + descriptor offset. and dword [eax + 4], ~0200h ; clear busy flag (2nd type2 bit) ltr word [edx + CPUMCPU.Host.tr] ; activate ldt DEBUG_CHAR('2') lldt [edx + CPUMCPU.Host.ldtr] ; Restore segment registers mov eax, [edx + CPUMCPU.Host.ds] mov ds, eax mov eax, [edx + CPUMCPU.Host.es] mov es, eax mov eax, [edx + CPUMCPU.Host.fs] mov fs, eax mov eax, [edx + CPUMCPU.Host.gs] mov gs, eax ; restore stack lss esp, [edx + CPUMCPU.Host.esp] ; Restore FPU if guest has used it. ; Using fxrstor should ensure that we're not causing unwanted exception on the host. mov esi, [edx + CPUMCPU.fUseFlags] ; esi == use flags. test esi, CPUM_USED_FPU jz near gth_fpu_no mov ecx, cr0 and ecx, ~(X86_CR0_TS | X86_CR0_EM) mov cr0, ecx fxsave [edx + CPUMCPU.Guest.fpu] fxrstor [edx + CPUMCPU.Host.fpu] jmp near gth_fpu_no ALIGNCODE(16) gth_fpu_no: ; Control registers. ; Would've liked to have these higher up in case of crashes, but ; the fpu stuff must be done before we restore cr0. mov ecx, [edx + CPUMCPU.Host.cr4] mov cr4, ecx mov ecx, [edx + CPUMCPU.Host.cr0] mov cr0, ecx ;mov ecx, [edx + CPUMCPU.Host.cr2] ; assumes this is waste of time. ;mov cr2, ecx ; restore general registers. mov eax, edi ; restore return code. eax = return code !! mov edi, [edx + CPUMCPU.Host.edi] mov esi, [edx + CPUMCPU.Host.esi] mov ebx, [edx + CPUMCPU.Host.ebx] mov ebp, [edx + CPUMCPU.Host.ebp] push dword [edx + CPUMCPU.Host.eflags] popfd %ifdef DEBUG_STUFF ; COM_S_CHAR '4' %endif retf ENDPROC VMMGCGuestToHostAsm ;; ; VMMGCGuestToHostAsmHyperCtx ; ; This is an alternative entry point which we'll be using ; when the we have the hypervisor context and need to save ; that before going to the host. ; ; This is typically useful when abandoning the hypervisor ; because of a trap and want the trap state to be saved. ; ; @param eax Return code. ; @param ecx Points to CPUMCTXCORE. ; @uses eax,edx,ecx ALIGNCODE(16) BEGINPROC VMMGCGuestToHostAsmHyperCtx int3 ;; ; VMMGCGuestToHostAsmGuestCtx ; ; Switches from Guest Context to Host Context. ; Of course it's only called from within the GC. ; ; @param eax Return code. ; @param esp + 4 Pointer to CPUMCTXCORE. ; ; @remark ASSUMES interrupts disabled. ; ALIGNCODE(16) BEGINPROC VMMGCGuestToHostAsmGuestCtx int3 GLOBALNAME End ; ; The description string (in the text section). ; NAME(Description): db SWITCHER_DESCRIPTION db 0 extern NAME(Relocate) ; ; End the fixup records. ; BEGINDATA db FIX_THE_END ; final entry. GLOBALNAME FixupsEnd ;; ; The switcher definition structure. ALIGNDATA(16) GLOBALNAME Def istruc VMMSWITCHERDEF at VMMSWITCHERDEF.pvCode, RTCCPTR_DEF NAME(Start) at VMMSWITCHERDEF.pvFixups, RTCCPTR_DEF NAME(Fixups) at VMMSWITCHERDEF.pszDesc, RTCCPTR_DEF NAME(Description) at VMMSWITCHERDEF.pfnRelocate, RTCCPTR_DEF NAME(Relocate) at VMMSWITCHERDEF.enmType, dd SWITCHER_TYPE at VMMSWITCHERDEF.cbCode, dd NAME(End) - NAME(Start) at VMMSWITCHERDEF.offR0HostToGuest, dd NAME(vmmR0HostToGuest) - NAME(Start) at VMMSWITCHERDEF.offGCGuestToHost, dd NAME(vmmGCGuestToHost) - NAME(Start) at VMMSWITCHERDEF.offGCCallTrampoline, dd NAME(vmmGCCallTrampoline) - NAME(Start) at VMMSWITCHERDEF.offGCGuestToHostAsm, dd NAME(VMMGCGuestToHostAsm) - NAME(Start) at VMMSWITCHERDEF.offGCGuestToHostAsmHyperCtx, dd NAME(VMMGCGuestToHostAsmHyperCtx)- NAME(Start) at VMMSWITCHERDEF.offGCGuestToHostAsmGuestCtx, dd NAME(VMMGCGuestToHostAsmGuestCtx)- NAME(Start) ; disasm help at VMMSWITCHERDEF.offHCCode0, dd 0 at VMMSWITCHERDEF.cbHCCode0, dd NAME(IDEnterTarget) - NAME(Start) at VMMSWITCHERDEF.offHCCode1, dd NAME(ICExitTarget) - NAME(Start) at VMMSWITCHERDEF.cbHCCode1, dd NAME(End) - NAME(ICExitTarget) at VMMSWITCHERDEF.offIDCode0, dd NAME(IDEnterTarget) - NAME(Start) at VMMSWITCHERDEF.cbIDCode0, dd NAME(ICEnterTarget) - NAME(IDEnterTarget) at VMMSWITCHERDEF.offIDCode1, dd NAME(IDExitTarget) - NAME(Start) at VMMSWITCHERDEF.cbIDCode1, dd NAME(ICExitTarget) - NAME(Start) at VMMSWITCHERDEF.offGCCode, dd 0 at VMMSWITCHERDEF.cbGCCode, dd 0 iend