path: root/arch/s390/kernel/entry64.S

/*
 *    S390 low-level entry points.
 *
 *    Copyright IBM Corp. 1999, 2012
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *		 Hartmut Penner (hp@de.ibm.com),
 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
 */

#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/processor.h>
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/unistd.h>
#include <asm/page.h>
#include <asm/sigp.h>
#include <asm/irq.h>

__PT_R0      =	__PT_GPRS
__PT_R1      =	__PT_GPRS + 8
__PT_R2      =	__PT_GPRS + 16
__PT_R3      =	__PT_GPRS + 24
__PT_R4      =	__PT_GPRS + 32
__PT_R5      =	__PT_GPRS + 40
__PT_R6      =	__PT_GPRS + 48
__PT_R7      =	__PT_GPRS + 56
__PT_R8      =	__PT_GPRS + 64
__PT_R9      =	__PT_GPRS + 72
__PT_R10     =	__PT_GPRS + 80
__PT_R11     =	__PT_GPRS + 88
__PT_R12     =	__PT_GPRS + 96
__PT_R13     =	__PT_GPRS + 104
__PT_R14     =	__PT_GPRS + 112
__PT_R15     =	__PT_GPRS + 120

STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE  = 1 << STACK_SHIFT
STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE

_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
		 _TIF_MCCK_PENDING | _TIF_PER_TRAP | _TIF_ASCE)
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
		 _TIF_MCCK_PENDING | _TIF_ASCE)
_TIF_TRACE    = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
		 _TIF_SYSCALL_TRACEPOINT)
_TIF_TRANSFER = (_TIF_MCCK_PENDING | _TIF_TLB_WAIT)

#define BASED(name) name-system_call(%r13)

	.macro	TRACE_IRQS_ON
#ifdef CONFIG_TRACE_IRQFLAGS
	basr	%r2,%r0
	brasl	%r14,trace_hardirqs_on_caller
#endif
	.endm

	.macro	TRACE_IRQS_OFF
#ifdef CONFIG_TRACE_IRQFLAGS
	basr	%r2,%r0
	brasl	%r14,trace_hardirqs_off_caller
#endif
	.endm

	.macro	LOCKDEP_SYS_EXIT
#ifdef CONFIG_LOCKDEP
	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
	jz	.+10
	brasl	%r14,lockdep_sys_exit
#endif
	.endm

	.macro LPP newpp
#if IS_ENABLED(CONFIG_KVM)
	tm	__LC_MACHINE_FLAGS+6,0x20	# MACHINE_FLAG_LPP
	jz	.+8
	.insn	s,0xb2800000,\newpp
#endif
	.endm

	.macro	HANDLE_SIE_INTERCEPT scratch,reason
#if IS_ENABLED(CONFIG_KVM)
	tmhh	%r8,0x0001		# interrupting from user ?
	jnz	.+62
	lgr	\scratch,%r9
	slg	\scratch,BASED(.Lsie_critical)
	clg	\scratch,BASED(.Lsie_critical_length)
	.if	\reason==1
	# Some program interrupts are suppressing (e.g. protection).
	# We must also check the instruction after SIE in that case.
	# do_protection_exception will rewind to rewind_pad
	jh	.+42
	.else
	jhe	.+42
	.endif
	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer
	LPP	__SF_EMPTY+16(%r15)		# set host id
	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE
	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
	larl	%r9,sie_exit			# skip forward to sie_exit
	mvi	__SF_EMPTY+31(%r15),\reason	# set exit reason
#endif
	.endm

	.macro	CHECK_STACK stacksize,savearea
#ifdef CONFIG_CHECK_STACK
	tml	%r15,\stacksize - CONFIG_STACK_GUARD
	lghi	%r14,\savearea
	jz	stack_overflow
#endif
	.endm

	.macro	SWITCH_ASYNC savearea,stack,shift
	tmhh	%r8,0x0001		# interrupting from user ?
	jnz	1f
	lgr	%r14,%r9
	slg	%r14,BASED(.Lcritical_start)
	clg	%r14,BASED(.Lcritical_length)
	jhe	0f
	lghi	%r11,\savearea		# inside critical section, do cleanup
	brasl	%r14,cleanup_critical
	tmhh	%r8,0x0001		# retest problem state after cleanup
	jnz	1f
0:	lg	%r14,\stack		# are we already on the target stack?
	slgr	%r14,%r15
	srag	%r14,%r14,\shift
	jnz	1f
	CHECK_STACK 1<<\shift,\savearea
	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
	j	2f
1:	lg	%r15,\stack		# load target stack
2:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
	.endm

	.macro UPDATE_VTIME scratch,enter_timer
	lg	\scratch,__LC_EXIT_TIMER
	slg	\scratch,\enter_timer
	alg	\scratch,__LC_USER_TIMER
	stg	\scratch,__LC_USER_TIMER
	lg	\scratch,__LC_LAST_UPDATE_TIMER
	slg