sdk/include/asm/trapamd64.inc

   1
   2 APIC_EOI = HEX(0FFFFFFFFFFFE00B0)
   3
   4 TF_VOLATILES            = HEX(01)
   5 TF_NONVOLATILES         = HEX(02)
   6 TF_XMM                  = HEX(04)
   7 TF_SEGMENTS             = HEX(08)
   8 TF_DEBUG                = HEX(10)
   9 TF_IRQL                 = HEX(20)
  10 TF_SAVE_ALL             = (TF_VOLATILES OR TF_NONVOLATILES OR TF_XMM OR TF_SEGMENTS)
  11 TF_HAS_ERROR_CODE       = HEX(40)
  12 TF_SEND_EOI             = HEX(80)
  13 //TF_SYSTEMSERVICE        = (TRAPFLAG_VOLATILES or TRAPFLAG_DEBUG)
  14 TF_CHECKUSERAPC         = HEX(100)
  15
  16 /*
  17  * Stack Layout:
  18  * |-------------------|
  19  * | KTRAP_FRAME       |
  20  * |-------------------| <- rbp
  21  * | EXCEPTION_RECORD  |
  22  * |-------------------|
  23  * | KEXCEPTION_FRAME  |
  24  * |-------------------| <- rsp
  25  *
  26  */
  27
  28 /*
  29  * EnterTrap - Allocate KTRAP_FRAME_LENGTH and save registers to it
  30  */
  31 MACRO(EnterTrap, Flags)
  32     LOCAL kernel_mode_entry
  33
  34     /* Save the trap flags for this trap */
  35     CurrentTrapFlags = VAL(Flags)
  36
  37     /* Size of hardware trap frame */
  38     if (Flags AND TF_HAS_ERROR_CODE)
  39         .pushframe code
  40         SIZE_INITIAL_FRAME = 6 * 8
  41     else
  42         .pushframe
  43         SIZE_INITIAL_FRAME = 5 * 8
  44     endif
  45
  46     /* Make room for a KTRAP_FRAME */
  47     sub rsp, (KTRAP_FRAME_LENGTH - SIZE_INITIAL_FRAME)
  48     .allocstack (KTRAP_FRAME_LENGTH - SIZE_INITIAL_FRAME)
  49
  50     /* Save rbp and rax */
  51     mov [rsp + KTRAP_FRAME_Rbp], rbp
  52     .savereg rbp, KTRAP_FRAME_Rbp
  53     mov [rsp + KTRAP_FRAME_Rax], rax
  54     .savereg rax, KTRAP_FRAME_Rax
  55
  56     /* Point rbp to the KTRAP_FRAME */
  57     lea rbp, [rsp]
  58     .setframe rbp, 0
  59
  60     if (Flags AND TF_NONVOLATILES)
  61         /* Save non-volatile registers */
  62         mov [rbp + KTRAP_FRAME_Rbx], rbx
  63         .savereg rbx, KTRAP_FRAME_Rbx
  64         mov [rbp + KTRAP_FRAME_Rdi], rdi
  65         .savereg rdi, KTRAP_FRAME_Rdi
  66         mov [rbp + KTRAP_FRAME_Rsi], rsi
  67         .savereg rsi, KTRAP_FRAME_Rsi
  68     endif
  69
  70     .endprolog
  71
  72     if (Flags AND TF_VOLATILES)
  73         /* Save volatile registers */
  74         mov [rbp + KTRAP_FRAME_Rcx], rcx
  75         mov [rbp + KTRAP_FRAME_Rdx], rdx
  76         mov [rbp + KTRAP_FRAME_R8], r8
  77         mov [rbp + KTRAP_FRAME_R9], r9
  78         mov [rbp + KTRAP_FRAME_R10], r10
  79         mov [rbp + KTRAP_FRAME_R11], r11
  80     endif
  81
  82     if (Flags AND TF_XMM)
  83         /* Save xmm registers */
  84         movdqa [rbp + KTRAP_FRAME_Xmm0], xmm0
  85         movdqa [rbp + KTRAP_FRAME_Xmm1], xmm1
  86         movdqa [rbp + KTRAP_FRAME_Xmm2], xmm2
  87         movdqa [rbp + KTRAP_FRAME_Xmm3], xmm3
  88         movdqa [rbp + KTRAP_FRAME_Xmm4], xmm4
  89         movdqa [rbp + KTRAP_FRAME_Xmm5], xmm5
  90     endif
  91
  92     if (Flags AND TF_SEGMENTS)
  93         /* Save segment selectors */
  94         mov [rbp + KTRAP_FRAME_SegDs], ds
  95         mov [rbp + KTRAP_FRAME_SegEs], es
  96         mov [rbp + KTRAP_FRAME_SegFs], fs
  97         mov [rbp + KTRAP_FRAME_SegGs], gs
  98     endif
  99
 100     /* Save previous mode and check if it was user mode */
 101     mov ax, [rbp + KTRAP_FRAME_SegCs]
 102     and al, 1
 103     mov [rbp + KTRAP_FRAME_PreviousMode], al
 104     jz kernel_mode_entry
 105
 106     /* Set sane segments */
 107     mov ax, (KGDT64_R3_DATA or RPL_MASK)
 108     mov ds, ax
 109     mov es, ax
 110     swapgs
 111
 112 kernel_mode_entry:
 113
 114 //    if (Flags AND TF_IRQL)
 115         /* Save previous irql */
 116         mov rax, cr8
 117         mov [rbp + KTRAP_FRAME_PreviousIrql], al
 118 //    endif
 119
 120     if (Flags AND TF_DEBUG)
 121         /* Save debug registers */
 122         mov rax, dr0
 123         mov [rbp + KTRAP_FRAME_Dr0], rax
 124         mov rax, dr1
 125         mov [rbp + KTRAP_FRAME_Dr1], rax
 126         mov rax, dr2
 127         mov [rbp + KTRAP_FRAME_Dr2], rax
 128         mov rax, dr3
 129         mov [rbp + KTRAP_FRAME_Dr3], rax
 130         mov rax, dr6
 131         mov [rbp + KTRAP_FRAME_Dr6], rax
 132         mov rax, dr7
 133         mov [rbp + KTRAP_FRAME_Dr7], rax
 134     endif
 135
 136     /* Make sure the direction flag is cleared */
 137     cld
 138 ENDM
 139
 140 /*
 141  *  ExitTrap - Restore registers and free stack space
 142  */
 143 MACRO(ExitTrap, Flags)
 144     LOCAL kernel_mode_return
 145
 146 #if DBG
 147         /* Check previous irql */
 148         mov rax, cr8
 149         cmp [rbp + KTRAP_FRAME_PreviousIrql], al
 150         je .irql_ok
 151         int 3
 152     .irql_ok:
 153 #endif
 154
 155     if (Flags AND TF_SEGMENTS)
 156         /* Restore segment selectors */
 157         mov ds, [rbp + KTRAP_FRAME_SegDs]
 158         mov es, [rbp + KTRAP_FRAME_SegEs]
 159         mov fs, [rbp + KTRAP_FRAME_SegFs]
 160     endif
 161
 162     if (Flags AND TF_IRQL)
 163         /* Restore previous irql */
 164         movzx rax, byte ptr [rbp + KTRAP_FRAME_PreviousIrql]
 165         mov cr8, rax
 166     endif
 167
 168     /* Check if we came from user mode */
 169     test byte ptr [rbp + KTRAP_FRAME_SegCs], 1
 170     jz kernel_mode_return
 171
 172     if (Flags AND TF_CHECKUSERAPC)
 173         /* Load current thread into r10 */
 174         mov r10, gs:[PcCurrentThread]
 175         cmp byte ptr [r10 + KTHREAD_UserApcPending], 0
 176         jne KiExitToUserApc
 177
 178     endif
 179
 180     /* Swap gs to user mode */
 181     swapgs
 182
 183 kernel_mode_return:
 184
 185     if (Flags AND TF_NONVOLATILES)
 186         /* Restore non-volatile registers */
 187         mov rbx, [rbp + KTRAP_FRAME_Rbx]
 188         mov rdi, [rbp + KTRAP_FRAME_Rdi]
 189         mov rsi, [rbp + KTRAP_FRAME_Rsi]
 190     endif
 191
 192     if (Flags AND TF_VOLATILES)
 193         /* Restore volatile registers */
 194         mov rax, [rbp + KTRAP_FRAME_Rax]
 195         mov rcx, [rbp + KTRAP_FRAME_Rcx]
 196         mov rdx, [rbp + KTRAP_FRAME_Rdx]
 197         mov r8, [rbp + KTRAP_FRAME_R8]
 198         mov r9, [rbp + KTRAP_FRAME_R9]
 199         mov r10, [rbp + KTRAP_FRAME_R10]
 200         mov r11, [rbp + KTRAP_FRAME_R11]
 201     endif
 202
 203     if (Flags AND TF_XMM)
 204         /* Restore xmm registers */
 205         movdqa xmm0, [rbp + KTRAP_FRAME_Xmm0]
 206         movdqa xmm1, [rbp + KTRAP_FRAME_Xmm1]
 207         movdqa xmm2, [rbp + KTRAP_FRAME_Xmm2]
 208         movdqa xmm3, [rbp + KTRAP_FRAME_Xmm3]
 209         movdqa xmm4, [rbp + KTRAP_FRAME_Xmm4]
 210         movdqa xmm5, [rbp + KTRAP_FRAME_Xmm5]
 211     endif
 212
 213     /* Restore rbp */
 214     mov rbp, [rbp + KTRAP_FRAME_Rbp]
 215
 216     /* Adjust stack pointer */
 217     add rsp, KTRAP_FRAME_Rip
 218
 219     if (Flags AND TF_SEND_EOI)
 220         /* Write 0 to the local APIC EOI register */
 221         mov dword ptr [APIC_EOI], 0
 222     endif
 223
 224     /* Return from the trap */
 225     iretq
 226 ENDM
 227
 228
 229 MACRO(TRAP_ENTRY, Trap, Flags)
 230     EXTERN Trap&Handler :PROC
 231     PUBLIC &Trap
 232     FUNC &Trap
 233         /* Common code to create the trap frame */
 234         EnterTrap Flags
 235
 236         /* Call the C handler */
 237         mov rcx, rbp
 238         call Trap&Handler
 239
 240         /* Leave */
 241         ExitTrap Flags
 242     ENDFUNC
 243 ENDM
 244