INCLUDE "exec/funcdef.i" INCLUDE "exec/exec_lib.i" INCLUDE "exec/nodes.i" INCLUDE "exec/lists.i" INCLUDE "exec/ables.i" INCLUDE "exec/tasks.i" INCLUDE "exec/ports.i" INCLUDE "exec/memory.i" INCLUDE "shared_defs.i" INCLUDE "macros.i" * $Id: switch_patch.asm,v 3.5 95/12/16 18:36:35 Martin_Apel Exp $ XDEF _SwitchPatch XDEF _AddTaskPatch XDEF _WaitPatch IFD DEBUG XDEF _RemTaskPatch XREF _OrigRemTask XDEF _StackSwapPatch XREF _OrigStackSwap ENDC XREF _OrigSwitch XREF _OrigAddTask XREF _OrigWait XREF _Free XREF _VirtAddrStart XREF _VirtAddrEnd XREF _ReportError IFD _PHXASS_ MACHINE MC68030 ENDC SECTION CODE * This routine is called in Supervisor mode just before the * registers of a task are saved onto the user stack by the * EXEC routine Switch. * It checks if the stackpointer lies within virtual ram. * Only then is the USP replaced by a pointer * to non-virtual ram. This is undone, when the task is next launched _SwitchPatch move.l a0,-(sp) move.l usp,a0 IN_VM a0,NoVirtMemSwitch * PRINT_DEB "Switch: SP = %lx",a0 movem.l d0/a1/a6,-(sp) lea _Free,a0 move.l 4,a6 REMHEAD tst.l d0 beq SVAlarm move.l ThisTask(a6),a1 move.l d0,a0 move.l a1,TS_FaultTask(a0) lea TS_TmpStack+TMP_STACKSIZE(a0),a1 move.l a0,-(a1) ; Start address of trap struct move.l usp,a0 move.l a0,-(a1) ; orig USP move.w 4*4(sp),-(a1) ; SR move.l 4*4+2(sp),-(a1) ; PC of task move.l a1,usp lea LaunchPatch(pc),a0 move.l a0,4*4+2(sp) movem.l (sp)+,d0/a1/a6 move.l (sp)+,a0 move.l _OrigSwitch,-(sp) rts ; call orig switch routine ALIGN_LONG NoVirtMemSwitch move.l (sp),a0 move.l _OrigSwitch,(sp) rts SVAlarm: PRINT_DEB "Switch: SV Alarm" move.l 4,a6 move.l #NoTrapStructsAlertNum,d7 jmp _LVOAlert(a6) ALIGN_LONG LaunchPatch: * The trap struct stack now contains the following: * high: | Start address of trap struct * | orig USP * | CCR.W * low : | PC of task * PRINT_DEB "Launch" move.l a2,([6,sp],-10) ; put a2 onto user stack move.l 6(sp),a2 ; orig USP sub.w #10,a2 move.l (sp),6(a2) ; orig PC move.w 4(sp),4(a2) ; CCR movem.l d0/a0-a1/a6,-(a2) move.l 10(sp),a1 lea _Free,a0 move.l 4,a6 FORBID ADDTAIL PERMIT move.l a2,sp movem.l (sp)+,d0/a0-a1/a6 move.l (sp)+,a2 rtr ********************************************************************* ALIGN_LONG _AddTaskPatch: * Called with the following parameters: * a1 : Pointer to Task * a2 : Initial PC * a3 : Final PC * a6 : SysBase PRINT_DEB "AddTask: PC = %lx. NewTaskName:",a2 IFD DEBUG move.l a1,-(sp) clr.l -(sp) move.l LN_NAME(a1),-(sp) jsr _PrintDebugMsg add.w #8,sp move.l (sp)+,a1 ENDC move.l TC_SPREG(a1),d0 IN_VM d0,NoVirtMemAdd PRINT_DEB "AddTask: Stack in VM. PC = %lx",a2 movem.l a2/a3,-(sp) move.l a1,-(sp) lea _Free,a0 FORBID REMHEAD ; Get a trap struct PERMIT move.l (sp)+,a1 ; Task tst.l d0 beq AddTaskAlarm move.l TC_SPREG(a1),a0 move.l a3,-(a0) ; FinalPC bne FinalPCValid move.l TaskExitCode(a6),(a0) FinalPCValid move.l d0,a3 ; TrapStruct move.l a5,-(sp) lea TS_TmpStack+TMP_STACKSIZE(a3),a5 move.l a3,-(a5) ; TrapStruct move.l a0,-(a5) ; orig USP clr.w -(a5) ; CCR move.l a5,TC_SPREG(a1) move.l (sp)+,a5 move.l a2,a3 lea LaunchPatch(pc),a2 move.l _OrigAddTask,a0 jsr (a0) movem.l (sp)+,a2-a3 rts ALIGN_LONG NoVirtMemAdd: move.l _OrigAddTask,a0 jmp (a0) AddTaskAlarm: PRINT_DEB "AddTaskAlarm" move.w #ERR_CONTINUE,-(sp) pea AddTaskAlarmText(pc) jsr _ReportError moveq #0,d0 jmp _LVOWait(a6) ; forever AddTaskAlarmText dc.b "No more trapstructs in AddTask." dc.b 10 ; LF dc.b "Adding task stopped",0 ds.l 0 ********************************************************************* ALIGN_LONG _WaitPatch: * Called with the following parameters: * d0 : Awaited Signals * a6 : SysBase * * Upon return: * d0 : Received Signals IN_VM sp,StackNotInVM move.l sp,a0 * PRINT_DEB "WaitPatch: Stack in VM at %lx",a0 lea _Free,a0 movem.l d2/a2,-(sp) move.l d0,d2 ; save awaited signals, ; so they can be accessed ; after StackSwap FORBID REMHEAD PERMIT tst.l d0 beq NoTrapStruct move.l d0,a2 lea TS_TmpStackSwap(a2),a0 jsr _LVOStackSwap(a6) move.l d2,d0 ; restore awaited signals move.l _OrigWait,a0 * PRINT_DEB "WaitPatch: Before Wait" jsr (a0) * PRINT_DEB "WaitPatch: Returned from Wait. Signals %08lx",d0 move.l d0,d2 ; save received signals lea TS_TmpStackSwap(a2),a0 jsr _LVOStackSwap(a6) lea _Free,a0 move.l a2,a1 FORBID ADDTAIL PERMIT move.l d2,d0 ; restore received signals movem.l (sp)+,d2/a2 rts NoTrapStruct: move.l d2,d0 movem.l (sp)+,d2/a2 PRINT_DEB "WaitPatch: No TrapStruct" bra StackNotInVM ALIGN_LONG StackNotInVM: move.l _OrigWait,a0 jmp (a0) ********************************************************************* IFD DEBUG _RemTaskPatch PRINT_DEB "Calling RemTask" move.l _OrigRemTask,a0 jsr (a0) PRINT_DEB "RemTask returned" rts ********************************************************************* _StackSwapPatch move.l sp,a1 PRINT_DEB "Calling StackSwap. CurrentStack: %lx",a1 move.l stk_Pointer(a0),d0 PRINT_DEB "New Stack at %lx",d0 move.l _OrigStackSwap,a1 jmp (a1) ENDC end