#include <os.h>#include <xen/features.h>.section __xen_guest	.ascii	"GUEST_OS=Mini-OS"	.ascii	",XEN_VER=xen-3.0"	.ascii	",VIRT_BASE=0x0" /* &_text from minios_x86_64.lds */	.ascii	",ELF_PADDR_OFFSET=0x0"	.ascii	",HYPERCALL_PAGE=0x2"	.ascii	",LOADER=generic"	.byte	0.text#define ENTRY(X) .globl X ; X :.globl _start, shared_info, hypercall_page_start:        cld        movq stack_start(%rip),%rsp        andq $(~(8192-1)), %rsp        movq %rsi,%rdi        call start_kernelstack_start:        .quad stack+(2*8192)        /* Unpleasant -- the PTE that maps this page is actually overwritten */        /* to map the real shared-info page! :-)                             */        .org 0x1000shared_info:        .org 0x2000hypercall_page:        .org 0x3000/* Offsets into shared_info_t. */                #define evtchn_upcall_pending		/* 0 */#define evtchn_upcall_mask		1NMI_MASK = 0x80000000#define RDI 112#define ORIG_RAX 120       /* + error_code */ #define EFLAGS 144#define REST_SKIP 6*8			.macro SAVE_REST	subq $REST_SKIP,%rsp#	CFI_ADJUST_CFA_OFFSET	REST_SKIP	movq %rbx,5*8(%rsp) #	CFI_REL_OFFSET	rbx,5*8	movq %rbp,4*8(%rsp) #	CFI_REL_OFFSET	rbp,4*8	movq %r12,3*8(%rsp) #	CFI_REL_OFFSET	r12,3*8	movq %r13,2*8(%rsp) #	CFI_REL_OFFSET	r13,2*8	movq %r14,1*8(%rsp) #	CFI_REL_OFFSET	r14,1*8	movq %r15,(%rsp) #	CFI_REL_OFFSET	r15,0*8.endm		.macro RESTORE_REST	movq (%rsp),%r15#	CFI_RESTORE r15	movq 1*8(%rsp),%r14#	CFI_RESTORE r14	movq 2*8(%rsp),%r13#	CFI_RESTORE r13	movq 3*8(%rsp),%r12#	CFI_RESTORE r12	movq 4*8(%rsp),%rbp#	CFI_RESTORE rbp	movq 5*8(%rsp),%rbx#	CFI_RESTORE rbx	addq $REST_SKIP,%rsp#	CFI_ADJUST_CFA_OFFSET	-(REST_SKIP).endm#define ARG_SKIP 9*8.macro RESTORE_ARGS skiprax=0,addskip=0,skiprcx=0,skipr11=0,skipr8910=0,skiprdx=0	.if \skipr11	.else	movq (%rsp),%r11#	CFI_RESTORE r11	.endif	.if \skipr8910	.else	movq 1*8(%rsp),%r10#	CFI_RESTORE r10	movq 2*8(%rsp),%r9#	CFI_RESTORE r9	movq 3*8(%rsp),%r8#	CFI_RESTORE r8	.endif	.if \skiprax	.else	movq 4*8(%rsp),%rax#	CFI_RESTORE rax	.endif	.if \skiprcx	.else	movq 5*8(%rsp),%rcx#	CFI_RESTORE rcx	.endif	.if \skiprdx	.else	movq 6*8(%rsp),%rdx#	CFI_RESTORE rdx	.endif	movq 7*8(%rsp),%rsi#	CFI_RESTORE rsi	movq 8*8(%rsp),%rdi#	CFI_RESTORE rdi	.if ARG_SKIP+\addskip > 0	addq $ARG_SKIP+\addskip,%rsp#	CFI_ADJUST_CFA_OFFSET	-(ARG_SKIP+\addskip)	.endif.endm	.macro HYPERVISOR_IRET flag#    testb $3,1*8(%rsp)    /* Don't need to do that in Mini-os, as */#	jnz   2f               /* there is no userspace? */	testl $NMI_MASK,2*8(%rsp)	jnz   2f	testb $1,(xen_features+XENFEAT_supervisor_mode_kernel)	jnz   1f	/* Direct iret to kernel space. Correct CS and SS. */	orb   $3,1*8(%rsp)	orb   $3,4*8(%rsp)1:	iretq2:	/* Slow iret via hypervisor. */	andl  $~NMI_MASK, 16(%rsp)	pushq $\flag	jmp  hypercall_page + (__HYPERVISOR_iret * 32).endm/* * Exception entry point. This expects an error code/orig_rax on the stack * and the exception handler in %rax.	 */ 		  				ENTRY(error_entry)#	_frame RDI	/* rdi slot contains rax, oldrax contains error code */	cld		subq  $14*8,%rsp#	CFI_ADJUST_CFA_OFFSET	(14*8)	movq %rsi,13*8(%rsp)#	CFI_REL_OFFSET	rsi,RSI	movq 14*8(%rsp),%rsi	/* load rax from rdi slot */	movq %rdx,12*8(%rsp)#	CFI_REL_OFFSET	rdx,RDX	movq %rcx,11*8(%rsp)#	CFI_REL_OFFSET	rcx,RCX	movq %rsi,10*8(%rsp)	/* store rax */ #	CFI_REL_OFFSET	rax,RAX	movq %r8, 9*8(%rsp)#	CFI_REL_OFFSET	r8,R8	movq %r9, 8*8(%rsp)#	CFI_REL_OFFSET	r9,R9	movq %r10,7*8(%rsp)#	CFI_REL_OFFSET	r10,R10	movq %r11,6*8(%rsp)#	CFI_REL_OFFSET	r11,R11	movq %rbx,5*8(%rsp) #	CFI_REL_OFFSET	rbx,RBX	movq %rbp,4*8(%rsp) #	CFI_REL_OFFSET	rbp,RBP	movq %r12,3*8(%rsp) #	CFI_REL_OFFSET	r12,R12	movq %r13,2*8(%rsp) #	CFI_REL_OFFSET	r13,R13	movq %r14,1*8(%rsp) #	CFI_REL_OFFSET	r14,R14	movq %r15,(%rsp) #	CFI_REL_OFFSET	r15,R15#if 0        	cmpl $__KERNEL_CS,CS(%rsp)	je  error_kernelspace#endif        error_call_handler:	movq %rdi, RDI(%rsp)            	movq %rsp,%rdi	movq ORIG_RAX(%rsp),%rsi	# get error code 	movq $-1,ORIG_RAX(%rsp)	call *%rax	jmp error_exit.macro zeroentry sym#	INTR_FRAME    movq (%rsp),%rcx    movq 8(%rsp),%r11    addq $0x10,%rsp /* skip rcx and r11 */	pushq $0	/* push error code/oldrax */ #	CFI_ADJUST_CFA_OFFSET 8	pushq %rax	/* push real oldrax to the rdi slot */ #	CFI_ADJUST_CFA_OFFSET 8	leaq  \sym(%rip),%rax	jmp error_entry#	CFI_ENDPROC.endm	.macro errorentry sym#	XCPT_FRAME        movq (%rsp),%rcx        movq 8(%rsp),%r11        addq $0x10,%rsp /* rsp points to the error code */	pushq %rax#	CFI_ADJUST_CFA_OFFSET 8	leaq  \sym(%rip),%rax	jmp error_entry#	CFI_ENDPROC.endm#define XEN_GET_VCPU_INFO(reg)	movq HYPERVISOR_shared_info,reg#define XEN_PUT_VCPU_INFO(reg)#define XEN_PUT_VCPU_INFO_fixup#define XEN_LOCKED_BLOCK_EVENTS(reg)	movb $1,evtchn_upcall_mask(reg)#define XEN_LOCKED_UNBLOCK_EVENTS(reg)	movb $0,evtchn_upcall_mask(reg)#define XEN_TEST_PENDING(reg)	testb $0xFF,evtchn_upcall_pending(reg)#define XEN_BLOCK_EVENTS(reg)	XEN_GET_VCPU_INFO(reg)			; \                    			XEN_LOCKED_BLOCK_EVENTS(reg)	; \    				            XEN_PUT_VCPU_INFO(reg)#define XEN_UNBLOCK_EVENTS(reg)	XEN_GET_VCPU_INFO(reg)			; \                				XEN_LOCKED_UNBLOCK_EVENTS(reg)	; \    			            	XEN_PUT_VCPU_INFO(reg)ENTRY(hypervisor_callback)    zeroentry hypervisor_callback2ENTRY(hypervisor_callback2)        movq %rdi, %rsp 11:     movq %gs:8,%rax        incl %gs:0        cmovzq %rax,%rsp        pushq %rdi        call do_hypervisor_callback         popq %rsp        decl %gs:0        jmp error_exit#        ALIGNrestore_all_enable_events:  	XEN_UNBLOCK_EVENTS(%rsi)        # %rsi is already set up...scrit:	/**** START OF CRITICAL REGION ****/	XEN_TEST_PENDING(%rsi)	jnz  14f			# process more events if necessary...	XEN_PUT_VCPU_INFO(%rsi)        RESTORE_ARGS 0,8,0        HYPERVISOR_IRET 0        14:	XEN_LOCKED_BLOCK_EVENTS(%rsi)	XEN_PUT_VCPU_INFO(%rsi)	SAVE_REST        movq %rsp,%rdi                  # set the argument again	jmp  11becrit:  /**** END OF CRITICAL REGION ****/retint_kernel:retint_restore_args:	movl EFLAGS-REST_SKIP(%rsp), %eax	shr $9, %eax			# EAX[0] == IRET_EFLAGS.IF	XEN_GET_VCPU_INFO(%rsi)	andb evtchn_upcall_mask(%rsi),%al	andb $1,%al			# EAX[0] == IRET_EFLAGS.IF & event_mask	jnz restore_all_enable_events	#        != 0 => enable event delivery	XEN_PUT_VCPU_INFO(%rsi)			RESTORE_ARGS 0,8,0	HYPERVISOR_IRET 0error_exit:			RESTORE_REST/*	cli */	XEN_BLOCK_EVENTS(%rsi)			jmp retint_kernelENTRY(failsafe_callback)        popq  %rcx        popq  %r11        iretqENTRY(coprocessor_error)        zeroentry do_coprocessor_errorENTRY(simd_coprocessor_error)        zeroentry do_simd_coprocessor_errorENTRY(device_not_available)        zeroentry do_device_not_availableENTRY(debug)#       INTR_FRAME#       CFI_ADJUST_CFA_OFFSET 8 */        zeroentry do_debug#       CFI_ENDPROCENTRY(int3)#       INTR_FRAME#       CFI_ADJUST_CFA_OFFSET 8 */        zeroentry do_int3#       CFI_ENDPROCENTRY(overflow)        zeroentry do_overflowENTRY(bounds)        zeroentry do_bounds        ENTRY(invalid_op)        zeroentry do_invalid_opENTRY(coprocessor_segment_overrun)        zeroentry do_coprocessor_segment_overrunENTRY(invalid_TSS)        errorentry do_invalid_TSSENTRY(segment_not_present)        errorentry do_segment_not_present/* runs on exception stack */ENTRY(stack_segment)#       XCPT_FRAME        errorentry do_stack_segment#       CFI_ENDPROC                    ENTRY(general_protection)        errorentry do_general_protectionENTRY(alignment_check)        errorentry do_alignment_checkENTRY(divide_error)        zeroentry do_divide_errorENTRY(spurious_interrupt_bug)        zeroentry do_spurious_interrupt_bug            ENTRY(page_fault)        errorentry do_page_faultENTRY(thread_starter)        popq %rdi        popq %rbx        pushq $0        xorq %rbp,%rbp        call *%rbx        call exit_thread         ENTRY(__arch_switch_threads)	pushq %rbp	pushq %rbx	pushq %r12	pushq %r13	pushq %r14	pushq %r15	movq %rsp, (%rdi)		/* save ESP */	movq (%rsi), %rsp		/* restore ESP */	movq $1f, 8(%rdi)		/* save EIP */	pushq 8(%rsi)			/* restore EIP */	ret1:	popq %r15	popq %r14	popq %r13	popq %r12	popq %rbx	popq %rbp	ret