Re: [Qemu-devel] passing translated address out in QEMU

[Xin Tong]

I am emulating arm on x86. i want to track the virt and physical
address of last memory operation. so i put 2 fields in the CPUState
and make tcg_global_mem_new_i32 on them Therefore, before every
translation i generate code to save the virtual address as follow:

static inline void gen_st32(TCGv val, TCGv addr, int index)
{
    tcg_gen_mov_i32(cpu_last_vaddr, addr);
    tcg_gen_qemu_st32(val, addr, index);
   // tcg_gen_mov_i32(cpu_last_paddr, addr);
    tcg_temp_free_i32(val);
}

But i do not know how to save the physical, as the physical address is
never passed out of tcg_gen_qemu_st32. what would be the best way to
get the physical address here ? i want to pass it out by the "TCGv
addr here" but it did not work ...

Xin




   0xf3753166:  mov    eax,DWORD PTR [ebp+0x18]
   0xf3753169:  mov    edx,eax
   0xf375316b:  mov    ecx,eax
   0xf375316d:  mov    DWORD PTR [ebp+0x6ccc],eax
   0xf3753173:  mov    DWORD PTR [ebp+0x3d4],edx
   0xf3753179:  mov    eax,0x4
   0xf375317e:  mov    DWORD PTR [ebp+0x3dc],eax
   0xf3753184:  xor    eax,eax
   0xf3753186:  mov    DWORD PTR [ebp+0x3e0],eax
   0xf375318c:  mov    edx,ecx
   0xf375318e:  mov    eax,ecx
   0xf3753190:  shr    edx,0x6
   0xf3753193:  and    eax,0xfffffc03
   0xf3753199:  and    edx,0xff0
   0xf375319f:  lea    edx,[ebp+edx*1+0x4c4]
   0xf37531a6:  cmp    eax,DWORD PTR [edx]
   0xf37531a8:  mov    eax,ecx
   0xf37531aa:  jne    0xf37531b3
   0xf37531ac:  add    eax,DWORD PTR [edx+0xc]
   0xf37531af:  mov    eax,DWORD PTR [eax]
   0xf37531b1:  jmp    0xf37531bc
   0xf37531b3:  xor    edx,edx
   0xf37531b5:  call   0x8184cb0 <__ldl_mmu>
   0xf37531ba:  mov    edx,eax
   0xf37531bc:  mov    edx,DWORD PTR [ebp+0x6ccc]
   0xf37531c2:  mov    DWORD PTR [esp],ebp
   0xf37531c5:  mov    ecx,0xf7d034ac
   0xf37531ca:  mov    DWORD PTR [esp+0x4],ecx
   0xf37531ce:  xor    ecx,ecx
   0xf37531d0:  mov    DWORD PTR [esp+0x8],ecx
   0xf37531d4:  mov    ecx,DWORD PTR [ebp+0x3d4]
   0xf37531da:  mov    DWORD PTR [esp+0xc],ecx
   0xf37531de:  mov    DWORD PTR [esp+0x10],edx
   0xf37531e2:  mov    DWORD PTR [ebp+0x4],eax
   0xf37531e5:  mov    DWORD PTR [ebp+0x3d8],edx



On Thu, Aug 23, 2012 at 3:11 AM, 陳韋任 (Wei-Ren Chen)
<address@hidden> wrote:
>> subtracting host virtual with a fixed offset for ram. but the thing i
>> do not know how to do is how to pass the guest physical back, can i
>> store the guest physical in the TCGv from the guest virtual.
>
>   Maybe you can store it on a host unused register, perhaps xmm0? ;)
>
> Regards,
> chenwj
>
> --
> Wei-Ren Chen (陳韋任)
> Computer Systems Lab, Institute of Information Science,
> Academia Sinica, Taiwan (R.O.C.)
> Tel:886-2-2788-3799 #1667
> Homepage: http://people.cs.nctu.edu.tw/~chenwj