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#include "xendefs.h"
#include "mem.h"
#define ENTRY(X) TEXT X(SB), $0
/*
* XXX there's a race in here because we can get an upcall
* betwen the spllo() (in xenupcall) and the rti. This will make
* handlers stack, which could lead to a blown stack. Probably
* not worth fixing (but possibly worth detecting and panicing).
*
* For fun get some popcorn and turn off the lights and read the
* linux solution (search for scrit/ecrit).
*/
ENTRY(hypervisor_callback)
SUBL $8, SP /* space for ecode and trap type */
PUSHL DS /* save DS */
PUSHL $(KDSEL)
POPL DS /* fix up DS */
PUSHL ES /* save ES */
PUSHL $(KDSEL)
POPL ES /* fix up ES */
PUSHL FS /* save the rest of the Ureg struct */
PUSHL GS
PUSHAL
PUSHL SP /* Ureg* argument to trap */
CALL xenupcall+0(SB)
POPL AX
POPAL
POPL GS
POPL FS
POPL ES
POPL DS
ADDL $8, SP /* pop error code and trap type */
IRETL
/* Hypervisor uses this for application faults while it executes.*/
ENTRY(failsafe_callback)
IRETL
PUSHL AX
CALL install_safe_pf_handler(SB)
MOVL 32(SP), BX
MOVW BX, DS
MOVL 36(SP), BX
MOVW BX, ES
MOVL 40(SP), BX
MOVW BX, FS
MOVL 44(SP), BX
MOVW BX, GS
CALL install_normal_pf_handler(SB)
POPL AX
ADDL $16, SP
IRETL
/* xen traps with varying argument counts */
TEXT xencall6(SB), $0
MOVL VDI+20(FP), DI
TEXT xencall5(SB), $0
MOVL VSI+16(FP), SI
TEXT xencall4(SB), $0
MOVL VDX+12(FP), DX
TEXT xencall3(SB), $0
MOVL VCX+8(FP), CX
TEXT xencall2(SB), $0
MOVL VBX+4(FP), BX
TEXT xencall1(SB), $0
MOVL op+0(FP), AX
INT $0x82
RET
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