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v5.4
   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
 
   3 *    S390 low-level entry points.
   4 *
   5 *    Copyright IBM Corp. 1999, 2012
   6 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   7 *		 Hartmut Penner (hp@de.ibm.com),
   8 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
   9 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
  10 */
  11
  12#include <linux/init.h>
  13#include <linux/linkage.h>
  14#include <asm/alternative-asm.h>
  15#include <asm/processor.h>
  16#include <asm/cache.h>
  17#include <asm/ctl_reg.h>
  18#include <asm/dwarf.h>
  19#include <asm/errno.h>
  20#include <asm/ptrace.h>
  21#include <asm/thread_info.h>
  22#include <asm/asm-offsets.h>
  23#include <asm/unistd.h>
  24#include <asm/page.h>
  25#include <asm/sigp.h>
  26#include <asm/irq.h>
  27#include <asm/vx-insn.h>
  28#include <asm/setup.h>
  29#include <asm/nmi.h>
  30#include <asm/export.h>
  31#include <asm/nospec-insn.h>
  32
  33__PT_R0      =	__PT_GPRS
  34__PT_R1      =	__PT_GPRS + 8
  35__PT_R2      =	__PT_GPRS + 16
  36__PT_R3      =	__PT_GPRS + 24
  37__PT_R4      =	__PT_GPRS + 32
  38__PT_R5      =	__PT_GPRS + 40
  39__PT_R6      =	__PT_GPRS + 48
  40__PT_R7      =	__PT_GPRS + 56
  41__PT_R8      =	__PT_GPRS + 64
  42__PT_R9      =	__PT_GPRS + 72
  43__PT_R10     =	__PT_GPRS + 80
  44__PT_R11     =	__PT_GPRS + 88
  45__PT_R12     =	__PT_GPRS + 96
  46__PT_R13     =	__PT_GPRS + 104
  47__PT_R14     =	__PT_GPRS + 112
  48__PT_R15     =	__PT_GPRS + 120
  49
  50STACK_SHIFT = PAGE_SHIFT + THREAD_SIZE_ORDER
  51STACK_SIZE  = 1 << STACK_SHIFT
  52STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
  53
  54_TIF_WORK	= (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
  55		   _TIF_UPROBE | _TIF_GUARDED_STORAGE | _TIF_PATCH_PENDING)
  56_TIF_TRACE	= (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
  57		   _TIF_SYSCALL_TRACEPOINT)
  58_CIF_WORK	= (_CIF_MCCK_PENDING | _CIF_ASCE_PRIMARY | \
  59		   _CIF_ASCE_SECONDARY | _CIF_FPU)
  60_PIF_WORK	= (_PIF_PER_TRAP | _PIF_SYSCALL_RESTART)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  61
  62_LPP_OFFSET	= __LC_LPP
 
  63
  64#define BASED(name) name-cleanup_critical(%r13)
  65
  66	.macro	TRACE_IRQS_ON
  67#ifdef CONFIG_TRACE_IRQFLAGS
 
  68	basr	%r2,%r0
  69	brasl	%r14,trace_hardirqs_on_caller
  70#endif
  71	.endm
  72
  73	.macro	TRACE_IRQS_OFF
  74#ifdef CONFIG_TRACE_IRQFLAGS
  75	basr	%r2,%r0
  76	brasl	%r14,trace_hardirqs_off_caller
  77#endif
  78	.endm
  79
  80	.macro	LOCKDEP_SYS_EXIT
  81#ifdef CONFIG_LOCKDEP
  82	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
  83	jz	.+10
  84	brasl	%r14,lockdep_sys_exit
  85#endif
  86	.endm
  87
  88	.macro	CHECK_STACK savearea
  89#ifdef CONFIG_CHECK_STACK
  90	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
  91	lghi	%r14,\savearea
  92	jz	stack_overflow
  93#endif
 
  94	.endm
  95
  96	.macro	CHECK_VMAP_STACK savearea,oklabel
  97#ifdef CONFIG_VMAP_STACK
  98	lgr	%r14,%r15
  99	nill	%r14,0x10000 - STACK_SIZE
 100	oill	%r14,STACK_INIT
 101	clg	%r14,__LC_KERNEL_STACK
 102	je	\oklabel
 103	clg	%r14,__LC_ASYNC_STACK
 104	je	\oklabel
 105	clg	%r14,__LC_NODAT_STACK
 106	je	\oklabel
 107	clg	%r14,__LC_RESTART_STACK
 108	je	\oklabel
 109	lghi	%r14,\savearea
 110	j	stack_overflow
 111#else
 112	j	\oklabel
 113#endif
 114	.endm
 115
 116	.macro	SWITCH_ASYNC savearea,timer
 117	tmhh	%r8,0x0001		# interrupting from user ?
 118	jnz	1f
 119	lgr	%r14,%r9
 120	slg	%r14,BASED(.Lcritical_start)
 121	clg	%r14,BASED(.Lcritical_length)
 122	jhe	0f
 123	lghi	%r11,\savearea		# inside critical section, do cleanup
 124	brasl	%r14,cleanup_critical
 125	tmhh	%r8,0x0001		# retest problem state after cleanup
 126	jnz	1f
 1270:	lg	%r14,__LC_ASYNC_STACK	# are we already on the target stack?
 128	slgr	%r14,%r15
 129	srag	%r14,%r14,STACK_SHIFT
 130	jnz	2f
 131	CHECK_STACK \savearea
 132	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
 133	j	3f
 1341:	UPDATE_VTIME %r14,%r15,\timer
 135	BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
 1362:	lg	%r15,__LC_ASYNC_STACK	# load async stack
 1373:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
 138	.endm
 139
 140	.macro UPDATE_VTIME w1,w2,enter_timer
 141	lg	\w1,__LC_EXIT_TIMER
 142	lg	\w2,__LC_LAST_UPDATE_TIMER
 143	slg	\w1,\enter_timer
 144	slg	\w2,__LC_EXIT_TIMER
 145	alg	\w1,__LC_USER_TIMER
 146	alg	\w2,__LC_SYSTEM_TIMER
 147	stg	\w1,__LC_USER_TIMER
 148	stg	\w2,__LC_SYSTEM_TIMER
 149	mvc	__LC_LAST_UPDATE_TIMER(8),\enter_timer
 150	.endm
 151
 152	.macro REENABLE_IRQS
 153	stg	%r8,__LC_RETURN_PSW
 154	ni	__LC_RETURN_PSW,0xbf
 155	ssm	__LC_RETURN_PSW
 156	.endm
 157
 158	.macro STCK savearea
 159#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
 160	.insn	s,0xb27c0000,\savearea		# store clock fast
 
 
 
 
 
 161#else
 162	.insn	s,0xb2050000,\savearea		# store clock
 163#endif
 
 
 164	.endm
 165
 166	/*
 167	 * The TSTMSK macro generates a test-under-mask instruction by
 168	 * calculating the memory offset for the specified mask value.
 169	 * Mask value can be any constant.  The macro shifts the mask
 170	 * value to calculate the memory offset for the test-under-mask
 171	 * instruction.
 172	 */
 173	.macro TSTMSK addr, mask, size=8, bytepos=0
 174		.if (\bytepos < \size) && (\mask >> 8)
 175			.if (\mask & 0xff)
 176				.error "Mask exceeds byte boundary"
 177			.endif
 178			TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)"
 179			.exitm
 180		.endif
 181		.ifeq \mask
 182			.error "Mask must not be zero"
 183		.endif
 184		off = \size - \bytepos - 1
 185		tm	off+\addr, \mask
 186	.endm
 187
 188	.macro BPOFF
 189	ALTERNATIVE "", ".long 0xb2e8c000", 82
 
 
 
 190	.endm
 191
 192	.macro BPON
 193	ALTERNATIVE "", ".long 0xb2e8d000", 82
 
 
 
 194	.endm
 195
 196	.macro BPENTER tif_ptr,tif_mask
 197	ALTERNATIVE "TSTMSK \tif_ptr,\tif_mask; jz .+8; .long 0xb2e8d000", \
 198		    "", 82
 
 
 
 
 
 199	.endm
 200
 201	.macro BPEXIT tif_ptr,tif_mask
 202	TSTMSK	\tif_ptr,\tif_mask
 203	ALTERNATIVE "jz .+8;  .long 0xb2e8c000", \
 204		    "jnz .+8; .long 0xb2e8d000", 82
 205	.endm
 206
 207	GEN_BR_THUNK %r9
 208	GEN_BR_THUNK %r14
 209	GEN_BR_THUNK %r14,%r11
 210
 211	.section .kprobes.text, "ax"
 212.Ldummy:
 213	/*
 214	 * This nop exists only in order to avoid that __switch_to starts at
 215	 * the beginning of the kprobes text section. In that case we would
 216	 * have several symbols at the same address. E.g. objdump would take
 217	 * an arbitrary symbol name when disassembling this code.
 218	 * With the added nop in between the __switch_to symbol is unique
 219	 * again.
 220	 */
 221	nop	0
 222
 223ENTRY(__bpon)
 224	.globl __bpon
 225	BPON
 226	BR_EX	%r14
 227ENDPROC(__bpon)
 228
 229/*
 230 * Scheduler resume function, called by switch_to
 231 *  gpr2 = (task_struct *) prev
 232 *  gpr3 = (task_struct *) next
 233 * Returns:
 234 *  gpr2 = prev
 235 */
 236ENTRY(__switch_to)
 237	stmg	%r6,%r15,__SF_GPRS(%r15)	# store gprs of prev task
 238	lghi	%r4,__TASK_stack
 239	lghi	%r1,__TASK_thread
 240	llill	%r5,STACK_INIT
 241	stg	%r15,__THREAD_ksp(%r1,%r2)	# store kernel stack of prev
 242	lg	%r15,0(%r4,%r3)			# start of kernel stack of next
 243	agr	%r15,%r5			# end of kernel stack of next
 244	stg	%r3,__LC_CURRENT		# store task struct of next
 245	stg	%r15,__LC_KERNEL_STACK		# store end of kernel stack
 246	lg	%r15,__THREAD_ksp(%r1,%r3)	# load kernel stack of next
 247	aghi	%r3,__TASK_pid
 248	mvc	__LC_CURRENT_PID(4,%r0),0(%r3)	# store pid of next
 249	lmg	%r6,%r15,__SF_GPRS(%r15)	# load gprs of next task
 250	ALTERNATIVE "", ".insn s,0xb2800000,_LPP_OFFSET", 40
 251	BR_EX	%r14
 252ENDPROC(__switch_to)
 253
 254.L__critical_start:
 255
 256#if IS_ENABLED(CONFIG_KVM)
 257/*
 258 * sie64a calling convention:
 259 * %r2 pointer to sie control block
 260 * %r3 guest register save area
 261 */
 262ENTRY(sie64a)
 263	stmg	%r6,%r14,__SF_GPRS(%r15)	# save kernel registers
 264	lg	%r12,__LC_CURRENT
 265	stg	%r2,__SF_SIE_CONTROL(%r15)	# save control block pointer
 266	stg	%r3,__SF_SIE_SAVEAREA(%r15)	# save guest register save area
 267	xc	__SF_SIE_REASON(8,%r15),__SF_SIE_REASON(%r15) # reason code = 0
 268	mvc	__SF_SIE_FLAGS(8,%r15),__TI_flags(%r12) # copy thread flags
 269	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU		# load guest fp/vx registers ?
 270	jno	.Lsie_load_guest_gprs
 271	brasl	%r14,load_fpu_regs		# load guest fp/vx regs
 272.Lsie_load_guest_gprs:
 273	lmg	%r0,%r13,0(%r3)			# load guest gprs 0-13
 274	lg	%r14,__LC_GMAP			# get gmap pointer
 275	ltgr	%r14,%r14
 276	jz	.Lsie_gmap
 277	lctlg	%c1,%c1,__GMAP_ASCE(%r14)	# load primary asce
 278.Lsie_gmap:
 279	lg	%r14,__SF_SIE_CONTROL(%r15)	# get control block pointer
 280	oi	__SIE_PROG0C+3(%r14),1		# we are going into SIE now
 281	tm	__SIE_PROG20+3(%r14),3		# last exit...
 282	jnz	.Lsie_skip
 283	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
 284	jo	.Lsie_skip			# exit if fp/vx regs changed
 285	BPEXIT	__SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
 286.Lsie_entry:
 287	sie	0(%r14)
 288.Lsie_exit:
 289	BPOFF
 290	BPENTER	__SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
 291.Lsie_skip:
 292	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE
 293	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
 294.Lsie_done:
 295# some program checks are suppressing. C code (e.g. do_protection_exception)
 296# will rewind the PSW by the ILC, which is often 4 bytes in case of SIE. There
 297# are some corner cases (e.g. runtime instrumentation) where ILC is unpredictable.
 298# Other instructions between sie64a and .Lsie_done should not cause program
 299# interrupts. So lets use 3 nops as a landing pad for all possible rewinds.
 300# See also .Lcleanup_sie
 301.Lrewind_pad6:
 302	nopr	7
 303.Lrewind_pad4:
 304	nopr	7
 305.Lrewind_pad2:
 306	nopr	7
 307	.globl sie_exit
 308sie_exit:
 309	lg	%r14,__SF_SIE_SAVEAREA(%r15)	# load guest register save area
 310	stmg	%r0,%r13,0(%r14)		# save guest gprs 0-13
 311	xgr	%r0,%r0				# clear guest registers to
 312	xgr	%r1,%r1				# prevent speculative use
 313	xgr	%r2,%r2
 314	xgr	%r3,%r3
 315	xgr	%r4,%r4
 316	xgr	%r5,%r5
 317	lmg	%r6,%r14,__SF_GPRS(%r15)	# restore kernel registers
 318	lg	%r2,__SF_SIE_REASON(%r15)	# return exit reason code
 319	BR_EX	%r14
 320.Lsie_fault:
 321	lghi	%r14,-EFAULT
 322	stg	%r14,__SF_SIE_REASON(%r15)	# set exit reason code
 323	j	sie_exit
 324
 325	EX_TABLE(.Lrewind_pad6,.Lsie_fault)
 326	EX_TABLE(.Lrewind_pad4,.Lsie_fault)
 327	EX_TABLE(.Lrewind_pad2,.Lsie_fault)
 328	EX_TABLE(sie_exit,.Lsie_fault)
 329ENDPROC(sie64a)
 330EXPORT_SYMBOL(sie64a)
 331EXPORT_SYMBOL(sie_exit)
 332#endif
 333
 
 334/*
 335 * SVC interrupt handler routine. System calls are synchronous events and
 336 * are executed with interrupts enabled.
 337 */
 338
 339ENTRY(system_call)
 340	stpt	__LC_SYNC_ENTER_TIMER
 341.Lsysc_stmg:
 342	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
 343	BPOFF
 344	lg	%r12,__LC_CURRENT
 345	lghi	%r13,__TASK_thread
 346	lghi	%r14,_PIF_SYSCALL
 347.Lsysc_per:
 348	lg	%r15,__LC_KERNEL_STACK
 349	la	%r11,STACK_FRAME_OVERHEAD(%r15)	# pointer to pt_regs
 350.Lsysc_vtime:
 351	UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
 352	BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
 353	stmg	%r0,%r7,__PT_R0(%r11)
 354	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
 355	mvc	__PT_PSW(16,%r11),__LC_SVC_OLD_PSW
 356	mvc	__PT_INT_CODE(4,%r11),__LC_SVC_ILC
 357	stg	%r14,__PT_FLAGS(%r11)
 358.Lsysc_do_svc:
 359	# clear user controlled register to prevent speculative use
 360	xgr	%r0,%r0
 361	# load address of system call table
 362	lg	%r10,__THREAD_sysc_table(%r13,%r12)
 363	llgh	%r8,__PT_INT_CODE+2(%r11)
 364	slag	%r8,%r8,3			# shift and test for svc 0
 365	jnz	.Lsysc_nr_ok
 366	# svc 0: system call number in %r1
 367	llgfr	%r1,%r1				# clear high word in r1
 368	cghi	%r1,NR_syscalls
 369	jnl	.Lsysc_nr_ok
 370	sth	%r1,__PT_INT_CODE+2(%r11)
 371	slag	%r8,%r1,3
 372.Lsysc_nr_ok:
 373	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
 374	stg	%r2,__PT_ORIG_GPR2(%r11)
 375	stg	%r7,STACK_FRAME_OVERHEAD(%r15)
 376	lg	%r9,0(%r8,%r10)			# get system call add.
 377	TSTMSK	__TI_flags(%r12),_TIF_TRACE
 378	jnz	.Lsysc_tracesys
 379	BASR_EX	%r14,%r9			# call sys_xxxx
 380	stg	%r2,__PT_R2(%r11)		# store return value
 381
 382.Lsysc_return:
 383#ifdef CONFIG_DEBUG_RSEQ
 384	lgr	%r2,%r11
 385	brasl	%r14,rseq_syscall
 386#endif
 387	LOCKDEP_SYS_EXIT
 388.Lsysc_tif:
 389	TSTMSK	__PT_FLAGS(%r11),_PIF_WORK
 390	jnz	.Lsysc_work
 391	TSTMSK	__TI_flags(%r12),_TIF_WORK
 392	jnz	.Lsysc_work			# check for work
 393	TSTMSK	__LC_CPU_FLAGS,_CIF_WORK
 394	jnz	.Lsysc_work
 395	BPEXIT	__TI_flags(%r12),_TIF_ISOLATE_BP
 396.Lsysc_restore:
 397	lg	%r14,__LC_VDSO_PER_CPU
 398	lmg	%r0,%r10,__PT_R0(%r11)
 399	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r11)
 400.Lsysc_exit_timer:
 401	stpt	__LC_EXIT_TIMER
 402	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
 403	lmg	%r11,%r15,__PT_R11(%r11)
 404	lpswe	__LC_RETURN_PSW
 405.Lsysc_done:
 406
 407#
 408# One of the work bits is on. Find out which one.
 409#
 410.Lsysc_work:
 411	TSTMSK	__LC_CPU_FLAGS,_CIF_MCCK_PENDING
 412	jo	.Lsysc_mcck_pending
 413	TSTMSK	__TI_flags(%r12),_TIF_NEED_RESCHED
 414	jo	.Lsysc_reschedule
 415	TSTMSK	__PT_FLAGS(%r11),_PIF_SYSCALL_RESTART
 416	jo	.Lsysc_syscall_restart
 417#ifdef CONFIG_UPROBES
 418	TSTMSK	__TI_flags(%r12),_TIF_UPROBE
 419	jo	.Lsysc_uprobe_notify
 420#endif
 421	TSTMSK	__TI_flags(%r12),_TIF_GUARDED_STORAGE
 422	jo	.Lsysc_guarded_storage
 423	TSTMSK	__PT_FLAGS(%r11),_PIF_PER_TRAP
 424	jo	.Lsysc_singlestep
 425#ifdef CONFIG_LIVEPATCH
 426	TSTMSK	__TI_flags(%r12),_TIF_PATCH_PENDING
 427	jo	.Lsysc_patch_pending	# handle live patching just before
 428					# signals and possible syscall restart
 429#endif
 430	TSTMSK	__PT_FLAGS(%r11),_PIF_SYSCALL_RESTART
 431	jo	.Lsysc_syscall_restart
 432	TSTMSK	__TI_flags(%r12),_TIF_SIGPENDING
 433	jo	.Lsysc_sigpending
 434	TSTMSK	__TI_flags(%r12),_TIF_NOTIFY_RESUME
 435	jo	.Lsysc_notify_resume
 436	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
 437	jo	.Lsysc_vxrs
 438	TSTMSK	__LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
 439	jnz	.Lsysc_asce
 440	j	.Lsysc_return		# beware of critical section cleanup
 441
 442#
 443# _TIF_NEED_RESCHED is set, call schedule
 444#
 445.Lsysc_reschedule:
 446	larl	%r14,.Lsysc_return
 447	jg	schedule
 448
 449#
 450# _CIF_MCCK_PENDING is set, call handler
 451#
 452.Lsysc_mcck_pending:
 453	larl	%r14,.Lsysc_return
 454	jg	s390_handle_mcck	# TIF bit will be cleared by handler
 455
 456#
 457# _CIF_ASCE_PRIMARY and/or _CIF_ASCE_SECONDARY set, load user space asce
 458#
 459.Lsysc_asce:
 460	ni	__LC_CPU_FLAGS+7,255-_CIF_ASCE_SECONDARY
 461	lctlg	%c7,%c7,__LC_VDSO_ASCE		# load secondary asce
 462	TSTMSK	__LC_CPU_FLAGS,_CIF_ASCE_PRIMARY
 463	jz	.Lsysc_return
 464#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
 465	tm	__LC_STFLE_FAC_LIST+3,0x10	# has MVCOS ?
 466	jnz	.Lsysc_set_fs_fixup
 467	ni	__LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY
 468	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
 469	j	.Lsysc_return
 470.Lsysc_set_fs_fixup:
 471#endif
 472	larl	%r14,.Lsysc_return
 473	jg	set_fs_fixup
 474
 475#
 476# CIF_FPU is set, restore floating-point controls and floating-point registers.
 477#
 478.Lsysc_vxrs:
 479	larl	%r14,.Lsysc_return
 480	jg	load_fpu_regs
 
 481
 482#
 483# _TIF_SIGPENDING is set, call do_signal
 484#
 485.Lsysc_sigpending:
 486	lgr	%r2,%r11		# pass pointer to pt_regs
 487	brasl	%r14,do_signal
 488	TSTMSK	__PT_FLAGS(%r11),_PIF_SYSCALL
 489	jno	.Lsysc_return
 490.Lsysc_do_syscall:
 491	lghi	%r13,__TASK_thread
 492	lmg	%r2,%r7,__PT_R2(%r11)	# load svc arguments
 493	lghi	%r1,0			# svc 0 returns -ENOSYS
 494	j	.Lsysc_do_svc
 495
 496#
 497# _TIF_NOTIFY_RESUME is set, call do_notify_resume
 498#
 499.Lsysc_notify_resume:
 500	lgr	%r2,%r11		# pass pointer to pt_regs
 501	larl	%r14,.Lsysc_return
 502	jg	do_notify_resume
 503
 504#
 505# _TIF_UPROBE is set, call uprobe_notify_resume
 506#
 507#ifdef CONFIG_UPROBES
 508.Lsysc_uprobe_notify:
 509	lgr	%r2,%r11		# pass pointer to pt_regs
 510	larl	%r14,.Lsysc_return
 511	jg	uprobe_notify_resume
 512#endif
 513
 514#
 515# _TIF_GUARDED_STORAGE is set, call guarded_storage_load
 516#
 517.Lsysc_guarded_storage:
 518	lgr	%r2,%r11		# pass pointer to pt_regs
 519	larl	%r14,.Lsysc_return
 520	jg	gs_load_bc_cb
 521#
 522# _TIF_PATCH_PENDING is set, call klp_update_patch_state
 523#
 524#ifdef CONFIG_LIVEPATCH
 525.Lsysc_patch_pending:
 526	lg	%r2,__LC_CURRENT	# pass pointer to task struct
 527	larl	%r14,.Lsysc_return
 528	jg	klp_update_patch_state
 529#endif
 530
 531#
 532# _PIF_PER_TRAP is set, call do_per_trap
 533#
 534.Lsysc_singlestep:
 535	ni	__PT_FLAGS+7(%r11),255-_PIF_PER_TRAP
 536	lgr	%r2,%r11		# pass pointer to pt_regs
 537	larl	%r14,.Lsysc_return
 538	jg	do_per_trap
 539
 540#
 541# _PIF_SYSCALL_RESTART is set, repeat the current system call
 542#
 543.Lsysc_syscall_restart:
 544	ni	__PT_FLAGS+7(%r11),255-_PIF_SYSCALL_RESTART
 545	lmg	%r1,%r7,__PT_R1(%r11)	# load svc arguments
 546	lg	%r2,__PT_ORIG_GPR2(%r11)
 547	j	.Lsysc_do_svc
 
 
 
 
 548
 549#
 550# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
 551# and after the system call
 552#
 553.Lsysc_tracesys:
 554	lgr	%r2,%r11		# pass pointer to pt_regs
 
 555	la	%r3,0
 556	llgh	%r0,__PT_INT_CODE+2(%r11)
 557	stg	%r0,__PT_R2(%r11)
 558	brasl	%r14,do_syscall_trace_enter
 559	lghi	%r0,NR_syscalls
 560	clgr	%r0,%r2
 561	jnh	.Lsysc_tracenogo
 562	sllg	%r8,%r2,3
 563	lg	%r9,0(%r8,%r10)
 564.Lsysc_tracego:
 565	lmg	%r3,%r7,__PT_R3(%r11)
 566	stg	%r7,STACK_FRAME_OVERHEAD(%r15)
 567	lg	%r2,__PT_ORIG_GPR2(%r11)
 568	BASR_EX	%r14,%r9		# call sys_xxx
 569	stg	%r2,__PT_R2(%r11)	# store return value
 570.Lsysc_tracenogo:
 571	TSTMSK	__TI_flags(%r12),_TIF_TRACE
 572	jz	.Lsysc_return
 573	lgr	%r2,%r11		# pass pointer to pt_regs
 574	larl	%r14,.Lsysc_return
 575	jg	do_syscall_trace_exit
 576ENDPROC(system_call)
 
 577
 578#
 579# a new process exits the kernel with ret_from_fork
 580#
 581ENTRY(ret_from_fork)
 582	la	%r11,STACK_FRAME_OVERHEAD(%r15)
 583	lg	%r12,__LC_CURRENT
 584	brasl	%r14,schedule_tail
 
 
 
 
 585	TRACE_IRQS_ON
 586	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
 587	tm	__PT_PSW+1(%r11),0x01	# forking a kernel thread ?
 588	jne	.Lsysc_tracenogo
 589	# it's a kernel thread
 590	lmg	%r9,%r10,__PT_R9(%r11)	# load gprs
 591	la	%r2,0(%r10)
 592	BASR_EX	%r14,%r9
 593	j	.Lsysc_tracenogo
 594ENDPROC(ret_from_fork)
 595
 596ENTRY(kernel_thread_starter)
 597	la	%r2,0(%r10)
 598	BASR_EX	%r14,%r9
 599	j	.Lsysc_tracenogo
 600ENDPROC(kernel_thread_starter)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 601
 602/*
 603 * Program check handler routine
 604 */
 605
 606ENTRY(pgm_check_handler)
 
 
 
 
 
 
 
 
 
 
 
 
 
 607	stpt	__LC_SYNC_ENTER_TIMER
 608	BPOFF
 609	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
 610	lg	%r10,__LC_LAST_BREAK
 611	lg	%r12,__LC_CURRENT
 612	lghi	%r11,0
 613	larl	%r13,cleanup_critical
 614	lmg	%r8,%r9,__LC_PGM_OLD_PSW
 615	tmhh	%r8,0x0001		# test problem state bit
 616	jnz	2f			# -> fault in user space
 617#if IS_ENABLED(CONFIG_KVM)
 618	# cleanup critical section for program checks in sie64a
 619	lgr	%r14,%r9
 620	slg	%r14,BASED(.Lsie_critical_start)
 621	clg	%r14,BASED(.Lsie_critical_length)
 622	jhe	0f
 623	lg	%r14,__SF_SIE_CONTROL(%r15)	# get control block pointer
 624	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE
 625	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
 626	larl	%r9,sie_exit			# skip forward to sie_exit
 627	lghi	%r11,_PIF_GUEST_FAULT
 628#endif
 6290:	tmhh	%r8,0x4000		# PER bit set in old PSW ?
 630	jnz	1f			# -> enabled, can't be a double fault
 631	tm	__LC_PGM_ILC+3,0x80	# check for per exception
 632	jnz	.Lpgm_svcper		# -> single stepped svc
 6331:	CHECK_STACK __LC_SAVE_AREA_SYNC
 634	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
 635	# CHECK_VMAP_STACK branches to stack_overflow or 4f
 636	CHECK_VMAP_STACK __LC_SAVE_AREA_SYNC,4f
 6372:	UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
 638	BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
 639	lg	%r15,__LC_KERNEL_STACK
 640	lgr	%r14,%r12
 641	aghi	%r14,__TASK_thread	# pointer to thread_struct
 642	lghi	%r13,__LC_PGM_TDB
 643	tm	__LC_PGM_ILC+2,0x02	# check for transaction abort
 644	jz	3f
 645	mvc	__THREAD_trap_tdb(256,%r14),0(%r13)
 6463:	stg	%r10,__THREAD_last_break(%r14)
 6474:	lgr	%r13,%r11
 648	la	%r11,STACK_FRAME_OVERHEAD(%r15)
 649	stmg	%r0,%r7,__PT_R0(%r11)
 650	# clear user controlled registers to prevent speculative use
 651	xgr	%r0,%r0
 652	xgr	%r1,%r1
 653	xgr	%r2,%r2
 654	xgr	%r3,%r3
 655	xgr	%r4,%r4
 656	xgr	%r5,%r5
 657	xgr	%r6,%r6
 658	xgr	%r7,%r7
 659	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
 660	stmg	%r8,%r9,__PT_PSW(%r11)
 661	mvc	__PT_INT_CODE(4,%r11),__LC_PGM_ILC
 662	mvc	__PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
 663	stg	%r13,__PT_FLAGS(%r11)
 664	stg	%r10,__PT_ARGS(%r11)
 665	tm	__LC_PGM_ILC+3,0x80	# check for per exception
 666	jz	5f
 667	tmhh	%r8,0x0001		# kernel per event ?
 668	jz	.Lpgm_kprobe
 669	oi	__PT_FLAGS+7(%r11),_PIF_PER_TRAP
 670	mvc	__THREAD_per_address(8,%r14),__LC_PER_ADDRESS
 671	mvc	__THREAD_per_cause(2,%r14),__LC_PER_CODE
 672	mvc	__THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID
 6735:	REENABLE_IRQS
 674	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
 675	larl	%r1,pgm_check_table
 676	llgh	%r10,__PT_INT_CODE+2(%r11)
 677	nill	%r10,0x007f
 678	sll	%r10,3
 679	je	.Lpgm_return
 680	lg	%r9,0(%r10,%r1)		# load address of handler routine
 681	lgr	%r2,%r11		# pass pointer to pt_regs
 682	BASR_EX	%r14,%r9		# branch to interrupt-handler
 683.Lpgm_return:
 684	LOCKDEP_SYS_EXIT
 685	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
 686	jno	.Lsysc_restore
 687	TSTMSK	__PT_FLAGS(%r11),_PIF_SYSCALL
 688	jo	.Lsysc_do_syscall
 689	j	.Lsysc_tif
 
 
 
 
 
 
 
 
 
 
 
 
 
 690
 691#
 692# PER event in supervisor state, must be kprobes
 693#
 694.Lpgm_kprobe:
 695	REENABLE_IRQS
 696	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
 697	lgr	%r2,%r11		# pass pointer to pt_regs
 698	brasl	%r14,do_per_trap
 699	j	.Lpgm_return
 700
 701#
 702# single stepped system call
 703#
 704.Lpgm_svcper:
 705	mvc	__LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
 706	lghi	%r13,__TASK_thread
 707	larl	%r14,.Lsysc_per
 708	stg	%r14,__LC_RETURN_PSW+8
 709	lghi	%r14,_PIF_SYSCALL | _PIF_PER_TRAP
 710	lpswe	__LC_RETURN_PSW		# branch to .Lsysc_per and enable irqs
 711ENDPROC(pgm_check_handler)
 712
 713/*
 714 * IO interrupt handler routine
 715 */
 
 716ENTRY(io_int_handler)
 717	STCK	__LC_INT_CLOCK
 718	stpt	__LC_ASYNC_ENTER_TIMER
 719	BPOFF
 720	stmg	%r8,%r15,__LC_SAVE_AREA_ASYNC
 721	lg	%r12,__LC_CURRENT
 722	larl	%r13,cleanup_critical
 723	lmg	%r8,%r9,__LC_IO_OLD_PSW
 724	SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
 725	stmg	%r0,%r7,__PT_R0(%r11)
 726	# clear user controlled registers to prevent speculative use
 727	xgr	%r0,%r0
 728	xgr	%r1,%r1
 729	xgr	%r2,%r2
 730	xgr	%r3,%r3
 731	xgr	%r4,%r4
 732	xgr	%r5,%r5
 733	xgr	%r6,%r6
 734	xgr	%r7,%r7
 735	xgr	%r10,%r10
 736	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
 737	stmg	%r8,%r9,__PT_PSW(%r11)
 738	mvc	__PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
 739	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
 740	TSTMSK	__LC_CPU_FLAGS,_CIF_IGNORE_IRQ
 741	jo	.Lio_restore
 742	TRACE_IRQS_OFF
 743	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
 744.Lio_loop:
 745	lgr	%r2,%r11		# pass pointer to pt_regs
 746	lghi	%r3,IO_INTERRUPT
 747	tm	__PT_INT_CODE+8(%r11),0x80	# adapter interrupt ?
 748	jz	.Lio_call
 749	lghi	%r3,THIN_INTERRUPT
 750.Lio_call:
 751	brasl	%r14,do_IRQ
 752	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_LPAR
 753	jz	.Lio_return
 754	tpi	0
 755	jz	.Lio_return
 756	mvc	__PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
 757	j	.Lio_loop
 758.Lio_return:
 759	LOCKDEP_SYS_EXIT
 760	TRACE_IRQS_ON
 761.Lio_tif:
 762	TSTMSK	__TI_flags(%r12),_TIF_WORK
 763	jnz	.Lio_work		# there is work to do (signals etc.)
 764	TSTMSK	__LC_CPU_FLAGS,_CIF_WORK
 765	jnz	.Lio_work
 766.Lio_restore:
 767	lg	%r14,__LC_VDSO_PER_CPU
 768	lmg	%r0,%r10,__PT_R0(%r11)
 769	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r11)
 770	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
 771	jno	.Lio_exit_kernel
 772	BPEXIT	__TI_flags(%r12),_TIF_ISOLATE_BP
 773.Lio_exit_timer:
 774	stpt	__LC_EXIT_TIMER
 775	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
 776.Lio_exit_kernel:
 777	lmg	%r11,%r15,__PT_R11(%r11)
 778	lpswe	__LC_RETURN_PSW
 779.Lio_done:
 780
 781#
 782# There is work todo, find out in which context we have been interrupted:
 783# 1) if we return to user space we can do all _TIF_WORK work
 784# 2) if we return to kernel code and kvm is enabled check if we need to
 785#    modify the psw to leave SIE
 786# 3) if we return to kernel code and preemptive scheduling is enabled check
 787#    the preemption counter and if it is zero call preempt_schedule_irq
 788# Before any work can be done, a switch to the kernel stack is required.
 789#
 790.Lio_work:
 791	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
 792	jo	.Lio_work_user		# yes -> do resched & signal
 793#ifdef CONFIG_PREEMPT
 794	# check for preemptive scheduling
 795	icm	%r0,15,__LC_PREEMPT_COUNT
 796	jnz	.Lio_restore		# preemption is disabled
 797	TSTMSK	__TI_flags(%r12),_TIF_NEED_RESCHED
 798	jno	.Lio_restore
 799	# switch to kernel stack
 800	lg	%r1,__PT_R15(%r11)
 801	aghi	%r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
 802	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
 803	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
 804	la	%r11,STACK_FRAME_OVERHEAD(%r1)
 805	lgr	%r15,%r1
 806	# TRACE_IRQS_ON already done at .Lio_return, call
 807	# TRACE_IRQS_OFF to keep things symmetrical
 808	TRACE_IRQS_OFF
 809	brasl	%r14,preempt_schedule_irq
 810	j	.Lio_return
 
 811#else
 812	j	.Lio_restore
 813#endif
 814
 815#
 816# Need to do work before returning to userspace, switch to kernel stack
 817#
 818.Lio_work_user:
 819	lg	%r1,__LC_KERNEL_STACK
 820	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
 821	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
 822	la	%r11,STACK_FRAME_OVERHEAD(%r1)
 823	lgr	%r15,%r1
 824
 825#
 826# One of the work bits is on. Find out which one.
 
 
 827#
 828.Lio_work_tif:
 829	TSTMSK	__LC_CPU_FLAGS,_CIF_MCCK_PENDING
 830	jo	.Lio_mcck_pending
 831	TSTMSK	__TI_flags(%r12),_TIF_NEED_RESCHED
 832	jo	.Lio_reschedule
 833#ifdef CONFIG_LIVEPATCH
 834	TSTMSK	__TI_flags(%r12),_TIF_PATCH_PENDING
 835	jo	.Lio_patch_pending
 836#endif
 837	TSTMSK	__TI_flags(%r12),_TIF_SIGPENDING
 838	jo	.Lio_sigpending
 839	TSTMSK	__TI_flags(%r12),_TIF_NOTIFY_RESUME
 840	jo	.Lio_notify_resume
 841	TSTMSK	__TI_flags(%r12),_TIF_GUARDED_STORAGE
 842	jo	.Lio_guarded_storage
 843	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
 844	jo	.Lio_vxrs
 845	TSTMSK	__LC_CPU_FLAGS,(_CIF_ASCE_PRIMARY|_CIF_ASCE_SECONDARY)
 846	jnz	.Lio_asce
 847	j	.Lio_return		# beware of critical section cleanup
 848
 849#
 850# _CIF_MCCK_PENDING is set, call handler
 851#
 852.Lio_mcck_pending:
 853	# TRACE_IRQS_ON already done at .Lio_return
 854	brasl	%r14,s390_handle_mcck	# TIF bit will be cleared by handler
 855	TRACE_IRQS_OFF
 856	j	.Lio_return
 857
 858#
 859# _CIF_ASCE_PRIMARY and/or CIF_ASCE_SECONDARY set, load user space asce
 860#
 861.Lio_asce:
 862	ni	__LC_CPU_FLAGS+7,255-_CIF_ASCE_SECONDARY
 863	lctlg	%c7,%c7,__LC_VDSO_ASCE		# load secondary asce
 864	TSTMSK	__LC_CPU_FLAGS,_CIF_ASCE_PRIMARY
 865	jz	.Lio_return
 866#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
 867	tm	__LC_STFLE_FAC_LIST+3,0x10	# has MVCOS ?
 868	jnz	.Lio_set_fs_fixup
 869	ni	__LC_CPU_FLAGS+7,255-_CIF_ASCE_PRIMARY
 870	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
 871	j	.Lio_return
 872.Lio_set_fs_fixup:
 873#endif
 874	larl	%r14,.Lio_return
 875	jg	set_fs_fixup
 876
 877#
 878# CIF_FPU is set, restore floating-point controls and floating-point registers.
 879#
 880.Lio_vxrs:
 881	larl	%r14,.Lio_return
 882	jg	load_fpu_regs
 883
 884#
 885# _TIF_GUARDED_STORAGE is set, call guarded_storage_load
 886#
 887.Lio_guarded_storage:
 888	# TRACE_IRQS_ON already done at .Lio_return
 889	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
 890	lgr	%r2,%r11		# pass pointer to pt_regs
 891	brasl	%r14,gs_load_bc_cb
 892	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
 893	TRACE_IRQS_OFF
 894	j	.Lio_return
 895
 896#
 897# _TIF_NEED_RESCHED is set, call schedule
 898#
 899.Lio_reschedule:
 900	# TRACE_IRQS_ON already done at .Lio_return
 901	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
 902	brasl	%r14,schedule		# call scheduler
 903	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
 
 904	TRACE_IRQS_OFF
 905	j	.Lio_return
 906
 907#
 908# _TIF_PATCH_PENDING is set, call klp_update_patch_state
 909#
 910#ifdef CONFIG_LIVEPATCH
 911.Lio_patch_pending:
 912	lg	%r2,__LC_CURRENT	# pass pointer to task struct
 913	larl	%r14,.Lio_return
 914	jg	klp_update_patch_state
 915#endif
 916
 917#
 918# _TIF_SIGPENDING or is set, call do_signal
 919#
 920.Lio_sigpending:
 921	# TRACE_IRQS_ON already done at .Lio_return
 922	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
 923	lgr	%r2,%r11		# pass pointer to pt_regs
 924	brasl	%r14,do_signal
 925	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
 
 926	TRACE_IRQS_OFF
 927	j	.Lio_return
 928
 929#
 930# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
 931#
 932.Lio_notify_resume:
 933	# TRACE_IRQS_ON already done at .Lio_return
 934	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
 935	lgr	%r2,%r11		# pass pointer to pt_regs
 936	brasl	%r14,do_notify_resume
 937	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
 
 938	TRACE_IRQS_OFF
 939	j	.Lio_return
 940ENDPROC(io_int_handler)
 941
 942/*
 943 * External interrupt handler routine
 944 */
 
 945ENTRY(ext_int_handler)
 946	STCK	__LC_INT_CLOCK
 947	stpt	__LC_ASYNC_ENTER_TIMER
 948	BPOFF
 949	stmg	%r8,%r15,__LC_SAVE_AREA_ASYNC
 950	lg	%r12,__LC_CURRENT
 951	larl	%r13,cleanup_critical
 952	lmg	%r8,%r9,__LC_EXT_OLD_PSW
 953	SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
 954	stmg	%r0,%r7,__PT_R0(%r11)
 955	# clear user controlled registers to prevent speculative use
 956	xgr	%r0,%r0
 957	xgr	%r1,%r1
 958	xgr	%r2,%r2
 959	xgr	%r3,%r3
 960	xgr	%r4,%r4
 961	xgr	%r5,%r5
 962	xgr	%r6,%r6
 963	xgr	%r7,%r7
 964	xgr	%r10,%r10
 965	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
 966	stmg	%r8,%r9,__PT_PSW(%r11)
 967	lghi	%r1,__LC_EXT_PARAMS2
 968	mvc	__PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
 969	mvc	__PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
 970	mvc	__PT_INT_PARM_LONG(8,%r11),0(%r1)
 971	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
 972	TSTMSK	__LC_CPU_FLAGS,_CIF_IGNORE_IRQ
 973	jo	.Lio_restore
 974	TRACE_IRQS_OFF
 975	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
 976	lgr	%r2,%r11		# pass pointer to pt_regs
 977	lghi	%r3,EXT_INTERRUPT
 978	brasl	%r14,do_IRQ
 979	j	.Lio_return
 980ENDPROC(ext_int_handler)
 981
 982/*
 983 * Load idle PSW. The second "half" of this function is in .Lcleanup_idle.
 984 */
 985ENTRY(psw_idle)
 986	stg	%r3,__SF_EMPTY(%r15)
 987	larl	%r1,.Lpsw_idle_lpsw+4
 988	stg	%r1,__SF_EMPTY+8(%r15)
 989	larl	%r1,smp_cpu_mtid
 990	llgf	%r1,0(%r1)
 991	ltgr	%r1,%r1
 992	jz	.Lpsw_idle_stcctm
 993	.insn	rsy,0xeb0000000017,%r1,5,__SF_EMPTY+16(%r15)
 994.Lpsw_idle_stcctm:
 995	oi	__LC_CPU_FLAGS+7,_CIF_ENABLED_WAIT
 996	BPON
 997	STCK	__CLOCK_IDLE_ENTER(%r2)
 998	stpt	__TIMER_IDLE_ENTER(%r2)
 999.Lpsw_idle_lpsw:
1000	lpswe	__SF_EMPTY(%r15)
1001	BR_EX	%r14
1002.Lpsw_idle_end:
1003ENDPROC(psw_idle)
1004
1005/*
1006 * Store floating-point controls and floating-point or vector register
1007 * depending whether the vector facility is available.	A critical section
1008 * cleanup assures that the registers are stored even if interrupted for
1009 * some other work.  The CIF_FPU flag is set to trigger a lazy restore
1010 * of the register contents at return from io or a system call.
1011 */
1012ENTRY(save_fpu_regs)
1013	lg	%r2,__LC_CURRENT
1014	aghi	%r2,__TASK_thread
1015	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
1016	jo	.Lsave_fpu_regs_exit
1017	stfpc	__THREAD_FPU_fpc(%r2)
1018	lg	%r3,__THREAD_FPU_regs(%r2)
1019	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_VX
1020	jz	.Lsave_fpu_regs_fp	  # no -> store FP regs
1021	VSTM	%v0,%v15,0,%r3		  # vstm 0,15,0(3)
1022	VSTM	%v16,%v31,256,%r3	  # vstm 16,31,256(3)
1023	j	.Lsave_fpu_regs_done	  # -> set CIF_FPU flag
1024.Lsave_fpu_regs_fp:
1025	std	0,0(%r3)
1026	std	1,8(%r3)
1027	std	2,16(%r3)
1028	std	3,24(%r3)
1029	std	4,32(%r3)
1030	std	5,40(%r3)
1031	std	6,48(%r3)
1032	std	7,56(%r3)
1033	std	8,64(%r3)
1034	std	9,72(%r3)
1035	std	10,80(%r3)
1036	std	11,88(%r3)
1037	std	12,96(%r3)
1038	std	13,104(%r3)
1039	std	14,112(%r3)
1040	std	15,120(%r3)
1041.Lsave_fpu_regs_done:
1042	oi	__LC_CPU_FLAGS+7,_CIF_FPU
1043.Lsave_fpu_regs_exit:
1044	BR_EX	%r14
1045.Lsave_fpu_regs_end:
1046ENDPROC(save_fpu_regs)
1047EXPORT_SYMBOL(save_fpu_regs)
1048
1049/*
1050 * Load floating-point controls and floating-point or vector registers.
1051 * A critical section cleanup assures that the register contents are
1052 * loaded even if interrupted for some other work.
1053 *
1054 * There are special calling conventions to fit into sysc and io return work:
1055 *	%r15:	<kernel stack>
1056 * The function requires:
1057 *	%r4
1058 */
1059load_fpu_regs:
1060	lg	%r4,__LC_CURRENT
1061	aghi	%r4,__TASK_thread
1062	TSTMSK	__LC_CPU_FLAGS,_CIF_FPU
1063	jno	.Lload_fpu_regs_exit
1064	lfpc	__THREAD_FPU_fpc(%r4)
1065	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_VX
1066	lg	%r4,__THREAD_FPU_regs(%r4)	# %r4 <- reg save area
1067	jz	.Lload_fpu_regs_fp		# -> no VX, load FP regs
1068	VLM	%v0,%v15,0,%r4
1069	VLM	%v16,%v31,256,%r4
1070	j	.Lload_fpu_regs_done
1071.Lload_fpu_regs_fp:
1072	ld	0,0(%r4)
1073	ld	1,8(%r4)
1074	ld	2,16(%r4)
1075	ld	3,24(%r4)
1076	ld	4,32(%r4)
1077	ld	5,40(%r4)
1078	ld	6,48(%r4)
1079	ld	7,56(%r4)
1080	ld	8,64(%r4)
1081	ld	9,72(%r4)
1082	ld	10,80(%r4)
1083	ld	11,88(%r4)
1084	ld	12,96(%r4)
1085	ld	13,104(%r4)
1086	ld	14,112(%r4)
1087	ld	15,120(%r4)
1088.Lload_fpu_regs_done:
1089	ni	__LC_CPU_FLAGS+7,255-_CIF_FPU
1090.Lload_fpu_regs_exit:
1091	BR_EX	%r14
1092.Lload_fpu_regs_end:
1093ENDPROC(load_fpu_regs)
1094
1095.L__critical_end:
1096
1097/*
1098 * Machine check handler routines
1099 */
 
1100ENTRY(mcck_int_handler)
1101	STCK	__LC_MCCK_CLOCK
1102	BPOFF
1103	la	%r1,4095		# validate r1
1104	spt	__LC_CPU_TIMER_SAVE_AREA-4095(%r1)	# validate cpu timer
1105	sckc	__LC_CLOCK_COMPARATOR			# validate comparator
1106	lam	%a0,%a15,__LC_AREGS_SAVE_AREA-4095(%r1) # validate acrs
1107	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# validate gprs
1108	lg	%r12,__LC_CURRENT
1109	larl	%r13,cleanup_critical
1110	lmg	%r8,%r9,__LC_MCK_OLD_PSW
1111	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_SYSTEM_DAMAGE
1112	jo	.Lmcck_panic		# yes -> rest of mcck code invalid
1113	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_CR_VALID
1114	jno	.Lmcck_panic		# control registers invalid -> panic
1115	la	%r14,4095
1116	lctlg	%c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r14) # validate ctl regs
1117	ptlb
1118	lg	%r11,__LC_MCESAD-4095(%r14) # extended machine check save area
1119	nill	%r11,0xfc00		# MCESA_ORIGIN_MASK
1120	TSTMSK	__LC_CREGS_SAVE_AREA+16-4095(%r14),CR2_GUARDED_STORAGE
1121	jno	0f
1122	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_GS_VALID
1123	jno	0f
1124	.insn	 rxy,0xe3000000004d,0,__MCESA_GS_SAVE_AREA(%r11) # LGSC
11250:	l	%r14,__LC_FP_CREG_SAVE_AREA-4095(%r14)
1126	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_FC_VALID
1127	jo	0f
1128	sr	%r14,%r14
11290:	sfpc	%r14
1130	TSTMSK	__LC_MACHINE_FLAGS,MACHINE_FLAG_VX
1131	jo	0f
1132	lghi	%r14,__LC_FPREGS_SAVE_AREA
1133	ld	%f0,0(%r14)
1134	ld	%f1,8(%r14)
1135	ld	%f2,16(%r14)
1136	ld	%f3,24(%r14)
1137	ld	%f4,32(%r14)
1138	ld	%f5,40(%r14)
1139	ld	%f6,48(%r14)
1140	ld	%f7,56(%r14)
1141	ld	%f8,64(%r14)
1142	ld	%f9,72(%r14)
1143	ld	%f10,80(%r14)
1144	ld	%f11,88(%r14)
1145	ld	%f12,96(%r14)
1146	ld	%f13,104(%r14)
1147	ld	%f14,112(%r14)
1148	ld	%f15,120(%r14)
1149	j	1f
11500:	VLM	%v0,%v15,0,%r11
1151	VLM	%v16,%v31,256,%r11
11521:	lghi	%r14,__LC_CPU_TIMER_SAVE_AREA
1153	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
1154	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_CPU_TIMER_VALID
1155	jo	3f
1156	la	%r14,__LC_SYNC_ENTER_TIMER
1157	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
1158	jl	0f
1159	la	%r14,__LC_ASYNC_ENTER_TIMER
11600:	clc	0(8,%r14),__LC_EXIT_TIMER
1161	jl	1f
1162	la	%r14,__LC_EXIT_TIMER
11631:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
1164	jl	2f
1165	la	%r14,__LC_LAST_UPDATE_TIMER
11662:	spt	0(%r14)
1167	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
11683:	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_PSW_MWP_VALID
1169	jno	.Lmcck_panic
1170	tmhh	%r8,0x0001		# interrupting from user ?
1171	jnz	4f
1172	TSTMSK	__LC_MCCK_CODE,MCCK_CODE_PSW_IA_VALID
1173	jno	.Lmcck_panic
11744:	ssm	__LC_PGM_NEW_PSW	# turn dat on, keep irqs off
1175	SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_MCCK_ENTER_TIMER
1176.Lmcck_skip:
1177	lghi	%r14,__LC_GPREGS_SAVE_AREA+64
1178	stmg	%r0,%r7,__PT_R0(%r11)
1179	# clear user controlled registers to prevent speculative use
1180	xgr	%r0,%r0
1181	xgr	%r1,%r1
1182	xgr	%r2,%r2
1183	xgr	%r3,%r3
1184	xgr	%r4,%r4
1185	xgr	%r5,%r5
1186	xgr	%r6,%r6
1187	xgr	%r7,%r7
1188	xgr	%r10,%r10
1189	mvc	__PT_R8(64,%r11),0(%r14)
1190	stmg	%r8,%r9,__PT_PSW(%r11)
1191	xc	__PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
1192	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
1193	lgr	%r2,%r11		# pass pointer to pt_regs
1194	brasl	%r14,s390_do_machine_check
1195	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
1196	jno	.Lmcck_return
1197	lg	%r1,__LC_KERNEL_STACK	# switch to kernel stack
1198	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
1199	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
1200	la	%r11,STACK_FRAME_OVERHEAD(%r1)
1201	lgr	%r15,%r1
1202	TSTMSK	__LC_CPU_FLAGS,_CIF_MCCK_PENDING
1203	jno	.Lmcck_return
 
 
 
 
 
1204	TRACE_IRQS_OFF
1205	brasl	%r14,s390_handle_mcck
 
1206	TRACE_IRQS_ON
1207.Lmcck_return:
1208	lg	%r14,__LC_VDSO_PER_CPU
1209	lmg	%r0,%r10,__PT_R0(%r11)
1210	mvc	__LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW
1211	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
1212	jno	0f
1213	BPEXIT	__TI_flags(%r12),_TIF_ISOLATE_BP
1214	stpt	__LC_EXIT_TIMER
1215	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
12160:	lmg	%r11,%r15,__PT_R11(%r11)
1217	lpswe	__LC_RETURN_MCCK_PSW
1218
1219.Lmcck_panic:
1220	lg	%r15,__LC_NODAT_STACK
1221	la	%r11,STACK_FRAME_OVERHEAD(%r15)
1222	j	.Lmcck_skip
1223ENDPROC(mcck_int_handler)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1224
1225#
1226# PSW restart interrupt handler
1227#
1228ENTRY(restart_int_handler)
1229	ALTERNATIVE "", ".insn s,0xb2800000,_LPP_OFFSET", 40
1230	stg	%r15,__LC_SAVE_AREA_RESTART
1231	lg	%r15,__LC_RESTART_STACK
1232	xc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r15),STACK_FRAME_OVERHEAD(%r15)
1233	stmg	%r0,%r14,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
1234	mvc	STACK_FRAME_OVERHEAD+__PT_R15(8,%r15),__LC_SAVE_AREA_RESTART
1235	mvc	STACK_FRAME_OVERHEAD+__PT_PSW(16,%r15),__LC_RST_OLD_PSW
1236	xc	0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
1237	lg	%r1,__LC_RESTART_FN		# load fn, parm & source cpu
1238	lg	%r2,__LC_RESTART_DATA
1239	lg	%r3,__LC_RESTART_SOURCE
1240	ltgr	%r3,%r3				# test source cpu address
1241	jm	1f				# negative -> skip source stop
12420:	sigp	%r4,%r3,SIGP_SENSE		# sigp sense to source cpu
1243	brc	10,0b				# wait for status stored
12441:	basr	%r14,%r1			# call function
1245	stap	__SF_EMPTY(%r15)		# store cpu address
1246	llgh	%r3,__SF_EMPTY(%r15)
12472:	sigp	%r4,%r3,SIGP_STOP		# sigp stop to current cpu
1248	brc	2,2b
12493:	j	3b
1250ENDPROC(restart_int_handler)
 
1251
1252	.section .kprobes.text, "ax"
1253
1254#if defined(CONFIG_CHECK_STACK) || defined(CONFIG_VMAP_STACK)
1255/*
1256 * The synchronous or the asynchronous stack overflowed. We are dead.
1257 * No need to properly save the registers, we are going to panic anyway.
1258 * Setup a pt_regs so that show_trace can provide a good call trace.
1259 */
1260ENTRY(stack_overflow)
1261	lg	%r15,__LC_NODAT_STACK	# change to panic stack
1262	la	%r11,STACK_FRAME_OVERHEAD(%r15)
1263	stmg	%r0,%r7,__PT_R0(%r11)
1264	stmg	%r8,%r9,__PT_PSW(%r11)
1265	mvc	__PT_R8(64,%r11),0(%r14)
1266	stg	%r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
1267	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
1268	lgr	%r2,%r11		# pass pointer to pt_regs
1269	jg	kernel_stack_overflow
1270ENDPROC(stack_overflow)
1271#endif
1272
1273ENTRY(cleanup_critical)
1274#if IS_ENABLED(CONFIG_KVM)
1275	clg	%r9,BASED(.Lcleanup_table_sie)	# .Lsie_gmap
1276	jl	0f
1277	clg	%r9,BASED(.Lcleanup_table_sie+8)# .Lsie_done
1278	jl	.Lcleanup_sie
1279#endif
1280	clg	%r9,BASED(.Lcleanup_table)	# system_call
1281	jl	0f
1282	clg	%r9,BASED(.Lcleanup_table+8)	# .Lsysc_do_svc
1283	jl	.Lcleanup_system_call
1284	clg	%r9,BASED(.Lcleanup_table+16)	# .Lsysc_tif
1285	jl	0f
1286	clg	%r9,BASED(.Lcleanup_table+24)	# .Lsysc_restore
1287	jl	.Lcleanup_sysc_tif
1288	clg	%r9,BASED(.Lcleanup_table+32)	# .Lsysc_done
1289	jl	.Lcleanup_sysc_restore
1290	clg	%r9,BASED(.Lcleanup_table+40)	# .Lio_tif
1291	jl	0f
1292	clg	%r9,BASED(.Lcleanup_table+48)	# .Lio_restore
1293	jl	.Lcleanup_io_tif
1294	clg	%r9,BASED(.Lcleanup_table+56)	# .Lio_done
1295	jl	.Lcleanup_io_restore
1296	clg	%r9,BASED(.Lcleanup_table+64)	# psw_idle
1297	jl	0f
1298	clg	%r9,BASED(.Lcleanup_table+72)	# .Lpsw_idle_end
1299	jl	.Lcleanup_idle
1300	clg	%r9,BASED(.Lcleanup_table+80)	# save_fpu_regs
1301	jl	0f
1302	clg	%r9,BASED(.Lcleanup_table+88)	# .Lsave_fpu_regs_end
1303	jl	.Lcleanup_save_fpu_regs
1304	clg	%r9,BASED(.Lcleanup_table+96)	# load_fpu_regs
1305	jl	0f
1306	clg	%r9,BASED(.Lcleanup_table+104)	# .Lload_fpu_regs_end
1307	jl	.Lcleanup_load_fpu_regs
13080:	BR_EX	%r14,%r11
1309ENDPROC(cleanup_critical)
1310
1311	.align	8
1312.Lcleanup_table:
1313	.quad	system_call
1314	.quad	.Lsysc_do_svc
1315	.quad	.Lsysc_tif
1316	.quad	.Lsysc_restore
1317	.quad	.Lsysc_done
1318	.quad	.Lio_tif
1319	.quad	.Lio_restore
1320	.quad	.Lio_done
1321	.quad	psw_idle
1322	.quad	.Lpsw_idle_end
1323	.quad	save_fpu_regs
1324	.quad	.Lsave_fpu_regs_end
1325	.quad	load_fpu_regs
1326	.quad	.Lload_fpu_regs_end
1327
1328#if IS_ENABLED(CONFIG_KVM)
1329.Lcleanup_table_sie:
1330	.quad	.Lsie_gmap
1331	.quad	.Lsie_done
1332
1333.Lcleanup_sie:
1334	cghi    %r11,__LC_SAVE_AREA_ASYNC 	#Is this in normal interrupt?
1335	je      1f
1336	slg     %r9,BASED(.Lsie_crit_mcck_start)
1337	clg     %r9,BASED(.Lsie_crit_mcck_length)
1338	jh      1f
1339	oi      __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST
13401:	BPENTER __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
1341	lg	%r9,__SF_SIE_CONTROL(%r15)	# get control block pointer
1342	ni	__SIE_PROG0C+3(%r9),0xfe	# no longer in SIE
1343	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
1344	larl	%r9,sie_exit			# skip forward to sie_exit
1345	BR_EX	%r14,%r11
1346#endif
1347
1348.Lcleanup_system_call:
1349	# check if stpt has been executed
1350	clg	%r9,BASED(.Lcleanup_system_call_insn)
1351	jh	0f
1352	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
1353	cghi	%r11,__LC_SAVE_AREA_ASYNC
1354	je	0f
1355	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
13560:	# check if stmg has been executed
1357	clg	%r9,BASED(.Lcleanup_system_call_insn+8)
1358	jh	0f
1359	mvc	__LC_SAVE_AREA_SYNC(64),0(%r11)
13600:	# check if base register setup + TIF bit load has been done
1361	clg	%r9,BASED(.Lcleanup_system_call_insn+16)
1362	jhe	0f
1363	# set up saved register r12 task struct pointer
1364	stg	%r12,32(%r11)
1365	# set up saved register r13 __TASK_thread offset
1366	mvc	40(8,%r11),BASED(.Lcleanup_system_call_const)
13670:	# check if the user time update has been done
1368	clg	%r9,BASED(.Lcleanup_system_call_insn+24)
1369	jh	0f
1370	lg	%r15,__LC_EXIT_TIMER
1371	slg	%r15,__LC_SYNC_ENTER_TIMER
1372	alg	%r15,__LC_USER_TIMER
1373	stg	%r15,__LC_USER_TIMER
13740:	# check if the system time update has been done
1375	clg	%r9,BASED(.Lcleanup_system_call_insn+32)
1376	jh	0f
1377	lg	%r15,__LC_LAST_UPDATE_TIMER
1378	slg	%r15,__LC_EXIT_TIMER
1379	alg	%r15,__LC_SYSTEM_TIMER
1380	stg	%r15,__LC_SYSTEM_TIMER
13810:	# update accounting time stamp
 
 
 
1382	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
1383	BPENTER __TI_flags(%r12),_TIF_ISOLATE_BP
1384	# set up saved register r11
1385	lg	%r15,__LC_KERNEL_STACK
1386	la	%r9,STACK_FRAME_OVERHEAD(%r15)
1387	stg	%r9,24(%r11)		# r11 pt_regs pointer
1388	# fill pt_regs
1389	mvc	__PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
1390	stmg	%r0,%r7,__PT_R0(%r9)
1391	mvc	__PT_PSW(16,%r9),__LC_SVC_OLD_PSW
1392	mvc	__PT_INT_CODE(4,%r9),__LC_SVC_ILC
1393	xc	__PT_FLAGS(8,%r9),__PT_FLAGS(%r9)
1394	mvi	__PT_FLAGS+7(%r9),_PIF_SYSCALL
1395	# setup saved register r15
1396	stg	%r15,56(%r11)		# r15 stack pointer
1397	# set new psw address and exit
1398	larl	%r9,.Lsysc_do_svc
1399	BR_EX	%r14,%r11
1400.Lcleanup_system_call_insn:
1401	.quad	system_call
1402	.quad	.Lsysc_stmg
1403	.quad	.Lsysc_per
1404	.quad	.Lsysc_vtime+36
1405	.quad	.Lsysc_vtime+42
1406.Lcleanup_system_call_const:
1407	.quad	__TASK_thread
1408
1409.Lcleanup_sysc_tif:
1410	larl	%r9,.Lsysc_tif
1411	BR_EX	%r14,%r11
1412
1413.Lcleanup_sysc_restore:
1414	# check if stpt has been executed
1415	clg	%r9,BASED(.Lcleanup_sysc_restore_insn)
1416	jh	0f
1417	mvc	__LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
1418	cghi	%r11,__LC_SAVE_AREA_ASYNC
1419	je	0f
1420	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
14210:	clg	%r9,BASED(.Lcleanup_sysc_restore_insn+8)
1422	je	1f
1423	lg	%r9,24(%r11)		# get saved pointer to pt_regs
1424	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r9)
1425	mvc	0(64,%r11),__PT_R8(%r9)
1426	lmg	%r0,%r7,__PT_R0(%r9)
14271:	lmg	%r8,%r9,__LC_RETURN_PSW
1428	BR_EX	%r14,%r11
1429.Lcleanup_sysc_restore_insn:
1430	.quad	.Lsysc_exit_timer
1431	.quad	.Lsysc_done - 4
1432
1433.Lcleanup_io_tif:
1434	larl	%r9,.Lio_tif
1435	BR_EX	%r14,%r11
1436
1437.Lcleanup_io_restore:
1438	# check if stpt has been executed
1439	clg	%r9,BASED(.Lcleanup_io_restore_insn)
1440	jh	0f
 
 
 
 
 
 
 
 
1441	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
14420:	clg	%r9,BASED(.Lcleanup_io_restore_insn+8)
1443	je	1f
1444	lg	%r9,24(%r11)		# get saved r11 pointer to pt_regs
1445	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r9)
1446	mvc	0(64,%r11),__PT_R8(%r9)
1447	lmg	%r0,%r7,__PT_R0(%r9)
14481:	lmg	%r8,%r9,__LC_RETURN_PSW
1449	BR_EX	%r14,%r11
1450.Lcleanup_io_restore_insn:
1451	.quad	.Lio_exit_timer
1452	.quad	.Lio_done - 4
1453
1454.Lcleanup_idle:
1455	ni	__LC_CPU_FLAGS+7,255-_CIF_ENABLED_WAIT
1456	# copy interrupt clock & cpu timer
1457	mvc	__CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
1458	mvc	__TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
1459	cghi	%r11,__LC_SAVE_AREA_ASYNC
1460	je	0f
1461	mvc	__CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
1462	mvc	__TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
14630:	# check if stck & stpt have been executed
1464	clg	%r9,BASED(.Lcleanup_idle_insn)
1465	jhe	1f
1466	mvc	__CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
1467	mvc	__TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2)
14681:	# calculate idle cycles
1469	clg	%r9,BASED(.Lcleanup_idle_insn)
1470	jl	3f
1471	larl	%r1,smp_cpu_mtid
1472	llgf	%r1,0(%r1)
1473	ltgr	%r1,%r1
1474	jz	3f
1475	.insn	rsy,0xeb0000000017,%r1,5,__SF_EMPTY+80(%r15)
1476	larl	%r3,mt_cycles
1477	ag	%r3,__LC_PERCPU_OFFSET
1478	la	%r4,__SF_EMPTY+16(%r15)
14792:	lg	%r0,0(%r3)
1480	slg	%r0,0(%r4)
1481	alg	%r0,64(%r4)
1482	stg	%r0,0(%r3)
1483	la	%r3,8(%r3)
1484	la	%r4,8(%r4)
1485	brct	%r1,2b
14863:	# account system time going idle
1487	lg	%r9,__LC_STEAL_TIMER
1488	alg	%r9,__CLOCK_IDLE_ENTER(%r2)
1489	slg	%r9,__LC_LAST_UPDATE_CLOCK
1490	stg	%r9,__LC_STEAL_TIMER
1491	mvc	__LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
1492	lg	%r9,__LC_SYSTEM_TIMER
1493	alg	%r9,__LC_LAST_UPDATE_TIMER
1494	slg	%r9,__TIMER_IDLE_ENTER(%r2)
1495	stg	%r9,__LC_SYSTEM_TIMER
1496	mvc	__LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
1497	# prepare return psw
1498	nihh	%r8,0xfcfd		# clear irq & wait state bits
1499	lg	%r9,48(%r11)		# return from psw_idle
1500	BR_EX	%r14,%r11
1501.Lcleanup_idle_insn:
1502	.quad	.Lpsw_idle_lpsw
1503
1504.Lcleanup_save_fpu_regs:
1505	larl	%r9,save_fpu_regs
1506	BR_EX	%r14,%r11
1507
1508.Lcleanup_load_fpu_regs:
1509	larl	%r9,load_fpu_regs
1510	BR_EX	%r14,%r11
1511
1512/*
1513 * Integer constants
1514 */
1515	.align	8
1516.Lcritical_start:
1517	.quad	.L__critical_start
1518.Lcritical_length:
1519	.quad	.L__critical_end - .L__critical_start
1520#if IS_ENABLED(CONFIG_KVM)
1521.Lsie_critical_start:
1522	.quad	.Lsie_gmap
1523.Lsie_critical_length:
1524	.quad	.Lsie_done - .Lsie_gmap
1525.Lsie_crit_mcck_start:
1526	.quad   .Lsie_entry
1527.Lsie_crit_mcck_length:
1528	.quad   .Lsie_skip - .Lsie_entry
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1529#endif
1530	.section .rodata, "a"
1531#define SYSCALL(esame,emu)	.quad __s390x_ ## esame
 
 
 
 
 
 
 
1532	.globl	sys_call_table
1533sys_call_table:
1534#include "asm/syscall_table.h"
1535#undef SYSCALL
1536
1537#ifdef CONFIG_COMPAT
1538
1539#define SYSCALL(esame,emu)	.quad __s390_ ## emu
1540	.globl	sys_call_table_emu
1541sys_call_table_emu:
1542#include "asm/syscall_table.h"
1543#undef SYSCALL
1544#endif
v3.1
 
   1/*
   2 *  arch/s390/kernel/entry.S
   3 *    S390 low-level entry points.
   4 *
   5 *    Copyright (C) IBM Corp. 1999,2006
   6 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   7 *		 Hartmut Penner (hp@de.ibm.com),
   8 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
   9 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
  10 */
  11
  12#include <linux/init.h>
  13#include <linux/linkage.h>
 
 
  14#include <asm/cache.h>
 
 
  15#include <asm/errno.h>
  16#include <asm/ptrace.h>
  17#include <asm/thread_info.h>
  18#include <asm/asm-offsets.h>
  19#include <asm/unistd.h>
  20#include <asm/page.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  21
  22/*
  23 * Stack layout for the system_call stack entry.
  24 * The first few entries are identical to the user_regs_struct.
  25 */
  26SP_PTREGS    =	STACK_FRAME_OVERHEAD
  27SP_ARGS      =	STACK_FRAME_OVERHEAD + __PT_ARGS
  28SP_PSW	     =	STACK_FRAME_OVERHEAD + __PT_PSW
  29SP_R0	     =	STACK_FRAME_OVERHEAD + __PT_GPRS
  30SP_R1	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 4
  31SP_R2	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 8
  32SP_R3	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 12
  33SP_R4	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 16
  34SP_R5	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 20
  35SP_R6	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 24
  36SP_R7	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 28
  37SP_R8	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 32
  38SP_R9	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 36
  39SP_R10	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 40
  40SP_R11	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 44
  41SP_R12	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 48
  42SP_R13	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 52
  43SP_R14	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 56
  44SP_R15	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 60
  45SP_ORIG_R2   =	STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
  46SP_ILC	     =	STACK_FRAME_OVERHEAD + __PT_ILC
  47SP_SVCNR     =	STACK_FRAME_OVERHEAD + __PT_SVCNR
  48SP_SIZE      =	STACK_FRAME_OVERHEAD + __PT_SIZE
  49
  50_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
  51		 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_PER_TRAP )
  52_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
  53		 _TIF_MCCK_PENDING)
  54_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
  55		_TIF_SECCOMP>>8 | _TIF_SYSCALL_TRACEPOINT>>8)
  56
  57STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
  58STACK_SIZE  = 1 << STACK_SHIFT
  59
  60#define BASED(name) name-system_call(%r13)
  61
 
  62#ifdef CONFIG_TRACE_IRQFLAGS
  63	.macro	TRACE_IRQS_ON
  64	basr	%r2,%r0
  65	l	%r1,BASED(.Ltrace_irq_on_caller)
  66	basr	%r14,%r1
  67	.endm
  68
  69	.macro	TRACE_IRQS_OFF
 
  70	basr	%r2,%r0
  71	l	%r1,BASED(.Ltrace_irq_off_caller)
  72	basr	%r14,%r1
  73	.endm
  74#else
  75#define TRACE_IRQS_ON
  76#define TRACE_IRQS_OFF
 
 
 
  77#endif
 
  78
  79#ifdef CONFIG_LOCKDEP
  80	.macro	LOCKDEP_SYS_EXIT
  81	tm	SP_PSW+1(%r15),0x01	# returning to user ?
  82	jz	0f
  83	l	%r1,BASED(.Llockdep_sys_exit)
  84	basr	%r14,%r1
  850:
  86	.endm
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  87#else
  88#define LOCKDEP_SYS_EXIT
  89#endif
 
  90
  91/*
  92 * Register usage in interrupt handlers:
  93 *    R9  - pointer to current task structure
  94 *    R13 - pointer to literal pool
  95 *    R14 - return register for function calls
  96 *    R15 - kernel stack pointer
  97 */
  98
  99	.macro	UPDATE_VTIME lc_from,lc_to,lc_sum
 100	lm	%r10,%r11,\lc_from
 101	sl	%r10,\lc_to
 102	sl	%r11,\lc_to+4
 103	bc	3,BASED(0f)
 104	sl	%r10,BASED(.Lc_1)
 1050:	al	%r10,\lc_sum
 106	al	%r11,\lc_sum+4
 107	bc	12,BASED(1f)
 108	al	%r10,BASED(.Lc_1)
 1091:	stm	%r10,%r11,\lc_sum
 
 
 
 110	.endm
 111
 112	.macro	SAVE_ALL_SVC psworg,savearea
 113	stm	%r12,%r15,\savearea
 114	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
 115	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
 116	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
 
 
 
 
 
 117	.endm
 118
 119	.macro	SAVE_ALL_BASE savearea
 120	stm	%r12,%r15,\savearea
 121	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
 
 122	.endm
 123
 124	.macro	SAVE_ALL_PGM psworg,savearea
 125	tm	\psworg+1,0x01		# test problem state bit
 126#ifdef CONFIG_CHECK_STACK
 127	bnz	BASED(1f)
 128	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
 129	bnz	BASED(2f)
 130	la	%r12,\psworg
 131	b	BASED(stack_overflow)
 132#else
 133	bz	BASED(2f)
 134#endif
 1351:	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
 1362:	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
 137	.endm
 138
 139	.macro	SAVE_ALL_ASYNC psworg,savearea
 140	stm	%r12,%r15,\savearea
 141	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
 142	la	%r12,\psworg
 143	tm	\psworg+1,0x01		# test problem state bit
 144	bnz	BASED(1f)		# from user -> load async stack
 145	clc	\psworg+4(4),BASED(.Lcritical_end)
 146	bhe	BASED(0f)
 147	clc	\psworg+4(4),BASED(.Lcritical_start)
 148	bl	BASED(0f)
 149	l	%r14,BASED(.Lcleanup_critical)
 150	basr	%r14,%r14
 151	tm	1(%r12),0x01		# retest problem state after cleanup
 152	bnz	BASED(1f)
 1530:	l	%r14,__LC_ASYNC_STACK	# are we already on the async stack ?
 154	slr	%r14,%r15
 155	sra	%r14,STACK_SHIFT
 156#ifdef CONFIG_CHECK_STACK
 157	bnz	BASED(1f)
 158	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
 159	bnz	BASED(2f)
 160	b	BASED(stack_overflow)
 161#else
 162	bz	BASED(2f)
 163#endif
 1641:	l	%r15,__LC_ASYNC_STACK
 1652:	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
 166	.endm
 167
 168	.macro	CREATE_STACK_FRAME savearea
 169	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
 170	st	%r2,SP_ORIG_R2(%r15)	# store original content of gpr 2
 171	mvc	SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
 172	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
 173	.endm
 174
 175	.macro	RESTORE_ALL psworg,sync
 176	mvc	\psworg(8),SP_PSW(%r15) # move user PSW to lowcore
 177	.if !\sync
 178	ni	\psworg+1,0xfd		# clear wait state bit
 179	.endif
 180	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15 of user
 181	stpt	__LC_EXIT_TIMER
 182	lpsw	\psworg			# back to caller
 183	.endm
 184
 185	.macro REENABLE_IRQS
 186	mvc	__SF_EMPTY(1,%r15),SP_PSW(%r15)
 187	ni	__SF_EMPTY(%r15),0xbf
 188	ssm	__SF_EMPTY(%r15)
 189	.endm
 190
 
 
 
 
 191	.section .kprobes.text, "ax"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 192
 193/*
 194 * Scheduler resume function, called by switch_to
 195 *  gpr2 = (task_struct *) prev
 196 *  gpr3 = (task_struct *) next
 197 * Returns:
 198 *  gpr2 = prev
 199 */
 200ENTRY(__switch_to)
 201	basr	%r1,0
 2020:	l	%r4,__THREAD_info(%r2)		# get thread_info of prev
 203	l	%r5,__THREAD_info(%r3)		# get thread_info of next
 204	tm	__TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
 205	bz	1f-0b(%r1)
 206	ni	__TI_flags+3(%r4),255-_TIF_MCCK_PENDING	# clear flag in prev
 207	oi	__TI_flags+3(%r5),_TIF_MCCK_PENDING	# set it in next
 2081:	stm	%r6,%r15,__SF_GPRS(%r15)	# store gprs of prev task
 209	st	%r15,__THREAD_ksp(%r2)		# store kernel stack of prev
 210	l	%r15,__THREAD_ksp(%r3)		# load kernel stack of next
 211	lctl	%c4,%c4,__TASK_pid(%r3)		# load pid to control reg. 4
 212	lm	%r6,%r15,__SF_GPRS(%r15)	# load gprs of next task
 213	st	%r3,__LC_CURRENT		# store task struct of next
 214	mvc	__LC_CURRENT_PID(4,%r0),__TASK_pid(%r3)	# store pid of next
 215	st	%r5,__LC_THREAD_INFO		# store thread info of next
 216	ahi	%r5,STACK_SIZE			# end of kernel stack of next
 217	st	%r5,__LC_KERNEL_STACK		# store end of kernel stack
 218	br	%r14
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 219
 220__critical_start:
 221/*
 222 * SVC interrupt handler routine. System calls are synchronous events and
 223 * are executed with interrupts enabled.
 224 */
 225
 226ENTRY(system_call)
 227	stpt	__LC_SYNC_ENTER_TIMER
 228sysc_saveall:
 229	SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
 230	CREATE_STACK_FRAME __LC_SAVE_AREA
 231	mvc	SP_PSW(8,%r15),__LC_SVC_OLD_PSW
 232	mvc	SP_ILC(4,%r15),__LC_SVC_ILC
 233	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 234sysc_vtime:
 235	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
 236sysc_stime:
 237	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 238sysc_update:
 239	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 240sysc_do_svc:
 241	xr	%r7,%r7
 242	icm	%r7,3,SP_SVCNR(%r15)	# load svc number and test for svc 0
 243	bnz	BASED(sysc_nr_ok)	# svc number > 0
 
 
 
 
 
 
 
 
 
 244	# svc 0: system call number in %r1
 245	cl	%r1,BASED(.Lnr_syscalls)
 246	bnl	BASED(sysc_nr_ok)
 247	sth	%r1,SP_SVCNR(%r15)
 248	lr	%r7,%r1 	  # copy svc number to %r7
 249sysc_nr_ok:
 250	sll	%r7,2		  # svc number *4
 251	l	%r10,BASED(.Lsysc_table)
 252	tm	__TI_flags+2(%r12),_TIF_SYSCALL
 253	mvc	SP_ARGS(4,%r15),SP_R7(%r15)
 254	l	%r8,0(%r7,%r10)	  # get system call addr.
 255	bnz	BASED(sysc_tracesys)
 256	basr	%r14,%r8	  # call sys_xxxx
 257	st	%r2,SP_R2(%r15)   # store return value (change R2 on stack)
 258
 259sysc_return:
 
 
 
 
 
 260	LOCKDEP_SYS_EXIT
 261sysc_tif:
 262	tm	__TI_flags+3(%r12),_TIF_WORK_SVC
 263	bnz	BASED(sysc_work)  # there is work to do (signals etc.)
 264sysc_restore:
 265	RESTORE_ALL __LC_RETURN_PSW,1
 266sysc_done:
 267
 268#
 269# There is work to do, but first we need to check if we return to userspace.
 270#
 271sysc_work:
 272	tm	SP_PSW+1(%r15),0x01	# returning to user ?
 273	bno	BASED(sysc_restore)
 
 
 
 
 
 274
 275#
 276# One of the work bits is on. Find out which one.
 277#
 278sysc_work_tif:
 279	tm	__TI_flags+3(%r12),_TIF_MCCK_PENDING
 280	bo	BASED(sysc_mcck_pending)
 281	tm	__TI_flags+3(%r12),_TIF_NEED_RESCHED
 282	bo	BASED(sysc_reschedule)
 283	tm	__TI_flags+3(%r12),_TIF_SIGPENDING
 284	bo	BASED(sysc_sigpending)
 285	tm	__TI_flags+3(%r12),_TIF_NOTIFY_RESUME
 286	bo	BASED(sysc_notify_resume)
 287	tm	__TI_flags+3(%r12),_TIF_RESTART_SVC
 288	bo	BASED(sysc_restart)
 289	tm	__TI_flags+3(%r12),_TIF_PER_TRAP
 290	bo	BASED(sysc_singlestep)
 291	b	BASED(sysc_return)	# beware of critical section cleanup
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 292
 293#
 294# _TIF_NEED_RESCHED is set, call schedule
 295#
 296sysc_reschedule:
 297	l	%r1,BASED(.Lschedule)
 298	la	%r14,BASED(sysc_return)
 299	br	%r1			# call scheduler
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 300
 301#
 302# _TIF_MCCK_PENDING is set, call handler
 303#
 304sysc_mcck_pending:
 305	l	%r1,BASED(.Ls390_handle_mcck)
 306	la	%r14,BASED(sysc_return)
 307	br	%r1			# TIF bit will be cleared by handler
 308
 309#
 310# _TIF_SIGPENDING is set, call do_signal
 311#
 312sysc_sigpending:
 313	ni	__TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
 314	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 315	l	%r1,BASED(.Ldo_signal)
 316	basr	%r14,%r1		# call do_signal
 317	tm	__TI_flags+3(%r12),_TIF_RESTART_SVC
 318	bo	BASED(sysc_restart)
 319	tm	__TI_flags+3(%r12),_TIF_PER_TRAP
 320	bo	BASED(sysc_singlestep)
 321	b	BASED(sysc_return)
 322
 323#
 324# _TIF_NOTIFY_RESUME is set, call do_notify_resume
 325#
 326sysc_notify_resume:
 327	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 328	l	%r1,BASED(.Ldo_notify_resume)
 329	la	%r14,BASED(sysc_return)
 330	br	%r1			# call do_notify_resume
 
 
 
 
 
 
 
 
 
 331
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 332
 333#
 334# _TIF_RESTART_SVC is set, set up registers and restart svc
 335#
 336sysc_restart:
 337	ni	__TI_flags+3(%r12),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
 338	l	%r7,SP_R2(%r15) 	# load new svc number
 339	mvc	SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
 340	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
 341	sth	%r7,SP_SVCNR(%r15)
 342	b	BASED(sysc_nr_ok)	# restart svc
 343
 344#
 345# _TIF_PER_TRAP is set, call do_per_trap
 346#
 347sysc_singlestep:
 348	ni	__TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
 349	xc	SP_SVCNR(2,%r15),SP_SVCNR(%r15)		# clear svc number
 350	la	%r2,SP_PTREGS(%r15)	# address of register-save area
 351	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
 352	la	%r14,BASED(sysc_return)	# load adr. of system return
 353	br	%r1			# branch to do_per_trap
 354
 355#
 356# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
 357# and after the system call
 358#
 359sysc_tracesys:
 360	l	%r1,BASED(.Ltrace_entry)
 361	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 362	la	%r3,0
 363	xr	%r0,%r0
 364	icm	%r0,3,SP_SVCNR(%r15)
 365	st	%r0,SP_R2(%r15)
 366	basr	%r14,%r1
 367	cl	%r2,BASED(.Lnr_syscalls)
 368	bnl	BASED(sysc_tracenogo)
 369	lr	%r7,%r2
 370	sll	%r7,2			# svc number *4
 371	l	%r8,0(%r7,%r10)
 372sysc_tracego:
 373	lm	%r3,%r6,SP_R3(%r15)
 374	mvc	SP_ARGS(4,%r15),SP_R7(%r15)
 375	l	%r2,SP_ORIG_R2(%r15)
 376	basr	%r14,%r8		# call sys_xxx
 377	st	%r2,SP_R2(%r15)		# store return value
 378sysc_tracenogo:
 379	tm	__TI_flags+2(%r12),_TIF_SYSCALL
 380	bz	BASED(sysc_return)
 381	l	%r1,BASED(.Ltrace_exit)
 382	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 383	la	%r14,BASED(sysc_return)
 384	br	%r1
 385
 386#
 387# a new process exits the kernel with ret_from_fork
 388#
 389ENTRY(ret_from_fork)
 390	l	%r13,__LC_SVC_NEW_PSW+4
 391	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 392	tm	SP_PSW+1(%r15),0x01	# forking a kernel thread ?
 393	bo	BASED(0f)
 394	st	%r15,SP_R15(%r15)	# store stack pointer for new kthread
 3950:	l	%r1,BASED(.Lschedtail)
 396	basr	%r14,%r1
 397	TRACE_IRQS_ON
 398	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
 399	b	BASED(sysc_tracenogo)
 400
 401#
 402# kernel_execve function needs to deal with pt_regs that is not
 403# at the usual place
 404#
 405ENTRY(kernel_execve)
 406	stm	%r12,%r15,48(%r15)
 407	lr	%r14,%r15
 408	l	%r13,__LC_SVC_NEW_PSW+4
 409	s	%r15,BASED(.Lc_spsize)
 410	st	%r14,__SF_BACKCHAIN(%r15)
 411	la	%r12,SP_PTREGS(%r15)
 412	xc	0(__PT_SIZE,%r12),0(%r12)
 413	l	%r1,BASED(.Ldo_execve)
 414	lr	%r5,%r12
 415	basr	%r14,%r1
 416	ltr	%r2,%r2
 417	be	BASED(0f)
 418	a	%r15,BASED(.Lc_spsize)
 419	lm	%r12,%r15,48(%r15)
 420	br	%r14
 421	# execve succeeded.
 4220:	stnsm	__SF_EMPTY(%r15),0xfc	# disable interrupts
 423	l	%r15,__LC_KERNEL_STACK	# load ksp
 424	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
 425	mvc	SP_PTREGS(__PT_SIZE,%r15),0(%r12)	# copy pt_regs
 426	l	%r12,__LC_THREAD_INFO
 427	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
 428	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
 429	l	%r1,BASED(.Lexecve_tail)
 430	basr	%r14,%r1
 431	b	BASED(sysc_return)
 432
 433/*
 434 * Program check handler routine
 435 */
 436
 437ENTRY(pgm_check_handler)
 438/*
 439 * First we need to check for a special case:
 440 * Single stepping an instruction that disables the PER event mask will
 441 * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
 442 * For a single stepped SVC the program check handler gets control after
 443 * the SVC new PSW has been loaded. But we want to execute the SVC first and
 444 * then handle the PER event. Therefore we update the SVC old PSW to point
 445 * to the pgm_check_handler and branch to the SVC handler after we checked
 446 * if we have to load the kernel stack register.
 447 * For every other possible cause for PER event without the PER mask set
 448 * we just ignore the PER event (FIXME: is there anything we have to do
 449 * for LPSW?).
 450 */
 451	stpt	__LC_SYNC_ENTER_TIMER
 452	SAVE_ALL_BASE __LC_SAVE_AREA
 453	tm	__LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
 454	bnz	BASED(pgm_per)		# got per exception -> special case
 455	SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
 456	CREATE_STACK_FRAME __LC_SAVE_AREA
 457	xc	SP_ILC(4,%r15),SP_ILC(%r15)
 458	mvc	SP_PSW(8,%r15),__LC_PGM_OLD_PSW
 459	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 460	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
 461	bz	BASED(pgm_no_vtime)
 462	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
 463	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 464	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 465pgm_no_vtime:
 466	l	%r3,__LC_PGM_ILC	# load program interruption code
 467	l	%r4,__LC_TRANS_EXC_CODE
 468	REENABLE_IRQS
 469	la	%r8,0x7f
 470	nr	%r8,%r3
 471	sll	%r8,2
 472	l	%r1,BASED(.Ljump_table)
 473	l	%r1,0(%r8,%r1)		# load address of handler routine
 474	la	%r2,SP_PTREGS(%r15)	# address of register-save area
 475	basr	%r14,%r1		# branch to interrupt-handler
 476pgm_exit:
 477	b	BASED(sysc_return)
 478
 479#
 480# handle per exception
 481#
 482pgm_per:
 483	tm	__LC_PGM_OLD_PSW,0x40	# test if per event recording is on
 484	bnz	BASED(pgm_per_std)	# ok, normal per event from user space
 485# ok its one of the special cases, now we need to find out which one
 486	clc	__LC_PGM_OLD_PSW(8),__LC_SVC_NEW_PSW
 487	be	BASED(pgm_svcper)
 488# no interesting special case, ignore PER event
 489	lm	%r12,%r15,__LC_SAVE_AREA
 490	lpsw	0x28
 491
 492#
 493# Normal per exception
 494#
 495pgm_per_std:
 496	SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
 497	CREATE_STACK_FRAME __LC_SAVE_AREA
 498	mvc	SP_PSW(8,%r15),__LC_PGM_OLD_PSW
 499	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 500	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
 501	bz	BASED(pgm_no_vtime2)
 502	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
 503	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 504	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 505pgm_no_vtime2:
 506	l	%r1,__TI_task(%r12)
 507	tm	SP_PSW+1(%r15),0x01	# kernel per event ?
 508	bz	BASED(kernel_per)
 509	mvc	__THREAD_per_cause(2,%r1),__LC_PER_CAUSE
 510	mvc	__THREAD_per_address(4,%r1),__LC_PER_ADDRESS
 511	mvc	__THREAD_per_paid(1,%r1),__LC_PER_PAID
 512	oi	__TI_flags+3(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
 513	l	%r3,__LC_PGM_ILC	# load program interruption code
 514	l	%r4,__LC_TRANS_EXC_CODE
 515	REENABLE_IRQS
 516	la	%r8,0x7f
 517	nr	%r8,%r3 		# clear per-event-bit and ilc
 518	be	BASED(pgm_exit2)	# only per or per+check ?
 519	sll	%r8,2
 520	l	%r1,BASED(.Ljump_table)
 521	l	%r1,0(%r8,%r1)		# load address of handler routine
 522	la	%r2,SP_PTREGS(%r15)	# address of register-save area
 523	basr	%r14,%r1		# branch to interrupt-handler
 524pgm_exit2:
 525	b	BASED(sysc_return)
 526
 527#
 528# it was a single stepped SVC that is causing all the trouble
 529#
 530pgm_svcper:
 531	SAVE_ALL_PGM __LC_SVC_OLD_PSW,__LC_SAVE_AREA
 532	CREATE_STACK_FRAME __LC_SAVE_AREA
 533	mvc	SP_PSW(8,%r15),__LC_SVC_OLD_PSW
 534	mvc	SP_ILC(4,%r15),__LC_SVC_ILC
 535	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 536	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
 537	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 538	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 539	l	%r8,__TI_task(%r12)
 540	mvc	__THREAD_per_cause(2,%r8),__LC_PER_CAUSE
 541	mvc	__THREAD_per_address(4,%r8),__LC_PER_ADDRESS
 542	mvc	__THREAD_per_paid(1,%r8),__LC_PER_PAID
 543	oi	__TI_flags+3(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
 544	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
 545	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
 546	b	BASED(sysc_do_svc)
 547
 548#
 549# per was called from kernel, must be kprobes
 550#
 551kernel_per:
 552	REENABLE_IRQS
 553	xc	SP_SVCNR(2,%r15),SP_SVCNR(%r15)
 554	la	%r2,SP_PTREGS(%r15)	# address of register-save area
 555	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
 556	basr	%r14,%r1		# branch to do_single_step
 557	b	BASED(pgm_exit)
 
 
 
 
 
 
 
 
 
 
 
 558
 559/*
 560 * IO interrupt handler routine
 561 */
 562
 563ENTRY(io_int_handler)
 564	stck	__LC_INT_CLOCK
 565	stpt	__LC_ASYNC_ENTER_TIMER
 566	SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
 567	CREATE_STACK_FRAME __LC_SAVE_AREA+16
 568	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
 569	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 570	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
 571	bz	BASED(io_no_vtime)
 572	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
 573	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 574	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
 575io_no_vtime:
 
 
 
 
 
 
 
 
 
 
 
 
 
 576	TRACE_IRQS_OFF
 577	l	%r1,BASED(.Ldo_IRQ)	# load address of do_IRQ
 578	la	%r2,SP_PTREGS(%r15)	# address of register-save area
 579	basr	%r14,%r1		# branch to standard irq handler
 580io_return:
 
 
 
 
 
 
 
 
 
 
 
 
 581	LOCKDEP_SYS_EXIT
 582	TRACE_IRQS_ON
 583io_tif:
 584	tm	__TI_flags+3(%r12),_TIF_WORK_INT
 585	bnz	BASED(io_work)		# there is work to do (signals etc.)
 586io_restore:
 587	RESTORE_ALL __LC_RETURN_PSW,0
 588io_done:
 
 
 
 
 
 
 
 
 
 
 
 
 
 589
 590#
 591# There is work todo, find out in which context we have been interrupted:
 592# 1) if we return to user space we can do all _TIF_WORK_INT work
 593# 2) if we return to kernel code and preemptive scheduling is enabled check
 
 
 594#    the preemption counter and if it is zero call preempt_schedule_irq
 595# Before any work can be done, a switch to the kernel stack is required.
 596#
 597io_work:
 598	tm	SP_PSW+1(%r15),0x01	# returning to user ?
 599	bo	BASED(io_work_user)	# yes -> do resched & signal
 600#ifdef CONFIG_PREEMPT
 601	# check for preemptive scheduling
 602	icm	%r0,15,__TI_precount(%r12)
 603	bnz	BASED(io_restore)	# preemption disabled
 604	tm	__TI_flags+3(%r12),_TIF_NEED_RESCHED
 605	bno	BASED(io_restore)
 606	# switch to kernel stack
 607	l	%r1,SP_R15(%r15)
 608	s	%r1,BASED(.Lc_spsize)
 609	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
 610	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
 611	lr	%r15,%r1
 612	# TRACE_IRQS_ON already done at io_return, call
 
 613	# TRACE_IRQS_OFF to keep things symmetrical
 614	TRACE_IRQS_OFF
 615	l	%r1,BASED(.Lpreempt_schedule_irq)
 616	basr	%r14,%r1		# call preempt_schedule_irq
 617	b	BASED(io_return)
 618#else
 619	b	BASED(io_restore)
 620#endif
 621
 622#
 623# Need to do work before returning to userspace, switch to kernel stack
 624#
 625io_work_user:
 626	l	%r1,__LC_KERNEL_STACK
 627	s	%r1,BASED(.Lc_spsize)
 628	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
 629	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
 630	lr	%r15,%r1
 631
 632#
 633# One of the work bits is on. Find out which one.
 634# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
 635#		and _TIF_MCCK_PENDING
 636#
 637io_work_tif:
 638	tm	__TI_flags+3(%r12),_TIF_MCCK_PENDING
 639	bo	BASED(io_mcck_pending)
 640	tm	__TI_flags+3(%r12),_TIF_NEED_RESCHED
 641	bo	BASED(io_reschedule)
 642	tm	__TI_flags+3(%r12),_TIF_SIGPENDING
 643	bo	BASED(io_sigpending)
 644	tm	__TI_flags+3(%r12),_TIF_NOTIFY_RESUME
 645	bo	BASED(io_notify_resume)
 646	b	BASED(io_return)	# beware of critical section cleanup
 647
 648#
 649# _TIF_MCCK_PENDING is set, call handler
 650#
 651io_mcck_pending:
 652	# TRACE_IRQS_ON already done at io_return
 653	l	%r1,BASED(.Ls390_handle_mcck)
 654	basr	%r14,%r1		# TIF bit will be cleared by handler
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 655	TRACE_IRQS_OFF
 656	b	BASED(io_return)
 657
 658#
 659# _TIF_NEED_RESCHED is set, call schedule
 660#
 661io_reschedule:
 662	# TRACE_IRQS_ON already done at io_return
 663	l	%r1,BASED(.Lschedule)
 664	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
 665	basr	%r14,%r1		# call scheduler
 666	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
 667	TRACE_IRQS_OFF
 668	b	BASED(io_return)
 669
 670#
 671# _TIF_SIGPENDING is set, call do_signal
 
 
 
 
 
 
 
 
 
 
 672#
 673io_sigpending:
 674	# TRACE_IRQS_ON already done at io_return
 675	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
 676	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 677	l	%r1,BASED(.Ldo_signal)
 678	basr	%r14,%r1		# call do_signal
 679	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
 680	TRACE_IRQS_OFF
 681	b	BASED(io_return)
 682
 683#
 684# _TIF_SIGPENDING is set, call do_signal
 685#
 686io_notify_resume:
 687	# TRACE_IRQS_ON already done at io_return
 688	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
 689	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 690	l	%r1,BASED(.Ldo_notify_resume)
 691	basr	%r14,%r1		# call do_signal
 692	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
 693	TRACE_IRQS_OFF
 694	b	BASED(io_return)
 
 695
 696/*
 697 * External interrupt handler routine
 698 */
 699
 700ENTRY(ext_int_handler)
 701	stck	__LC_INT_CLOCK
 702	stpt	__LC_ASYNC_ENTER_TIMER
 703	SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
 704	CREATE_STACK_FRAME __LC_SAVE_AREA+16
 705	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
 706	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 707	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
 708	bz	BASED(ext_no_vtime)
 709	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
 710	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 711	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
 712ext_no_vtime:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 713	TRACE_IRQS_OFF
 714	la	%r2,SP_PTREGS(%r15)	# address of register-save area
 715	l	%r3,__LC_CPU_ADDRESS	# get cpu address + interruption code
 716	l	%r4,__LC_EXT_PARAMS	# get external parameters
 717	l	%r1,BASED(.Ldo_extint)
 718	basr	%r14,%r1
 719	b	BASED(io_return)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 720
 721__critical_end:
 722
 723/*
 724 * Machine check handler routines
 725 */
 726
 727ENTRY(mcck_int_handler)
 728	stck	__LC_MCCK_CLOCK
 729	spt	__LC_CPU_TIMER_SAVE_AREA	# revalidate cpu timer
 730	lm	%r0,%r15,__LC_GPREGS_SAVE_AREA	# revalidate gprs
 731	SAVE_ALL_BASE __LC_SAVE_AREA+32
 732	la	%r12,__LC_MCK_OLD_PSW
 733	tm	__LC_MCCK_CODE,0x80	# system damage?
 734	bo	BASED(mcck_int_main)	# yes -> rest of mcck code invalid
 735	mvc	__LC_MCCK_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
 736	tm	__LC_MCCK_CODE+5,0x02	# stored cpu timer value valid?
 737	bo	BASED(1f)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 738	la	%r14,__LC_SYNC_ENTER_TIMER
 739	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
 740	bl	BASED(0f)
 741	la	%r14,__LC_ASYNC_ENTER_TIMER
 7420:	clc	0(8,%r14),__LC_EXIT_TIMER
 743	bl	BASED(0f)
 744	la	%r14,__LC_EXIT_TIMER
 7450:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
 746	bl	BASED(0f)
 747	la	%r14,__LC_LAST_UPDATE_TIMER
 7480:	spt	0(%r14)
 749	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
 7501:	tm	__LC_MCCK_CODE+2,0x09	# mwp + ia of old psw valid?
 751	bno	BASED(mcck_int_main)	# no -> skip cleanup critical
 752	tm	__LC_MCK_OLD_PSW+1,0x01	# test problem state bit
 753	bnz	BASED(mcck_int_main)	# from user -> load async stack
 754	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_end)
 755	bhe	BASED(mcck_int_main)
 756	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_start)
 757	bl	BASED(mcck_int_main)
 758	l	%r14,BASED(.Lcleanup_critical)
 759	basr	%r14,%r14
 760mcck_int_main:
 761	l	%r14,__LC_PANIC_STACK	# are we already on the panic stack?
 762	slr	%r14,%r15
 763	sra	%r14,PAGE_SHIFT
 764	be	BASED(0f)
 765	l	%r15,__LC_PANIC_STACK	# load panic stack
 7660:	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
 767	CREATE_STACK_FRAME __LC_SAVE_AREA+32
 768	mvc	SP_PSW(8,%r15),0(%r12)
 769	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
 770	tm	__LC_MCCK_CODE+2,0x08	# mwp of old psw valid?
 771	bno	BASED(mcck_no_vtime)	# no -> skip cleanup critical
 772	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
 773	bz	BASED(mcck_no_vtime)
 774	UPDATE_VTIME __LC_EXIT_TIMER,__LC_MCCK_ENTER_TIMER,__LC_USER_TIMER
 775	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 776	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
 777mcck_no_vtime:
 778	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 779	l	%r1,BASED(.Ls390_mcck)
 780	basr	%r14,%r1		# call machine check handler
 781	tm	SP_PSW+1(%r15),0x01	# returning to user ?
 782	bno	BASED(mcck_return)
 783	l	%r1,__LC_KERNEL_STACK	# switch to kernel stack
 784	s	%r1,BASED(.Lc_spsize)
 785	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
 786	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
 787	lr	%r15,%r1
 788	stosm	__SF_EMPTY(%r15),0x04	# turn dat on
 789	tm	__TI_flags+3(%r12),_TIF_MCCK_PENDING
 790	bno	BASED(mcck_return)
 791	TRACE_IRQS_OFF
 792	l	%r1,BASED(.Ls390_handle_mcck)
 793	basr	%r14,%r1		# call machine check handler
 794	TRACE_IRQS_ON
 795mcck_return:
 796	mvc	__LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
 797	ni	__LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
 
 798	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
 799	bno	BASED(0f)
 800	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
 801	stpt	__LC_EXIT_TIMER
 802	lpsw	__LC_RETURN_MCCK_PSW	# back to caller
 8030:	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
 804	lpsw	__LC_RETURN_MCCK_PSW	# back to caller
 805
 806	RESTORE_ALL __LC_RETURN_MCCK_PSW,0
 807
 808/*
 809 * Restart interruption handler, kick starter for additional CPUs
 810 */
 811#ifdef CONFIG_SMP
 812	__CPUINIT
 813ENTRY(restart_int_handler)
 814	basr	%r1,0
 815restart_base:
 816	spt	restart_vtime-restart_base(%r1)
 817	stck	__LC_LAST_UPDATE_CLOCK
 818	mvc	__LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
 819	mvc	__LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
 820	l	%r15,__LC_SAVE_AREA+60	# load ksp
 821	lctl	%c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
 822	lam	%a0,%a15,__LC_AREGS_SAVE_AREA
 823	lm	%r6,%r15,__SF_GPRS(%r15) # load registers from clone
 824	l	%r1,__LC_THREAD_INFO
 825	mvc	__LC_USER_TIMER(8),__TI_user_timer(%r1)
 826	mvc	__LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
 827	xc	__LC_STEAL_TIMER(8),__LC_STEAL_TIMER
 828	stosm	__SF_EMPTY(%r15),0x04	# now we can turn dat on
 829	basr	%r14,0
 830	l	%r14,restart_addr-.(%r14)
 831	basr	%r14,%r14		# branch to start_secondary
 832restart_addr:
 833	.long	start_secondary
 834	.align	8
 835restart_vtime:
 836	.long	0x7fffffff,0xffffffff
 837	.previous
 838#else
 839/*
 840 * If we do not run with SMP enabled, let the new CPU crash ...
 841 */
 842ENTRY(restart_int_handler)
 843	basr	%r1,0
 844restart_base:
 845	lpsw	restart_crash-restart_base(%r1)
 846	.align	8
 847restart_crash:
 848	.long	0x000a0000,0x00000000
 849restart_go:
 850#endif
 851
 852#
 853# PSW restart interrupt handler
 854#
 855ENTRY(psw_restart_int_handler)
 856	st	%r15,__LC_SAVE_AREA_64(%r0)	# save r15
 857	basr	%r15,0
 8580:	l	%r15,.Lrestart_stack-0b(%r15)	# load restart stack
 859	l	%r15,0(%r15)
 860	ahi	%r15,-SP_SIZE			# make room for pt_regs
 861	stm	%r0,%r14,SP_R0(%r15)		# store gprs %r0-%r14 to stack
 862	mvc	SP_R15(4,%r15),__LC_SAVE_AREA_64(%r0)# store saved %r15 to stack
 863	mvc	SP_PSW(8,%r15),__LC_RST_OLD_PSW(%r0) # store restart old psw
 864	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # set backchain to 0
 865	basr	%r14,0
 8661:	l	%r14,.Ldo_restart-1b(%r14)
 867	basr	%r14,%r14
 868
 869	basr	%r14,0				# load disabled wait PSW if
 8702:	lpsw	restart_psw_crash-2b(%r14)	# do_restart returns
 871	.align 4
 872.Ldo_restart:
 873	.long	do_restart
 874.Lrestart_stack:
 875	.long	restart_stack
 876	.align 8
 877restart_psw_crash:
 878	.long	0x000a0000,0x00000000 + restart_psw_crash
 879
 880	.section .kprobes.text, "ax"
 881
 882#ifdef CONFIG_CHECK_STACK
 883/*
 884 * The synchronous or the asynchronous stack overflowed. We are dead.
 885 * No need to properly save the registers, we are going to panic anyway.
 886 * Setup a pt_regs so that show_trace can provide a good call trace.
 887 */
 888stack_overflow:
 889	l	%r15,__LC_PANIC_STACK	# change to panic stack
 890	sl	%r15,BASED(.Lc_spsize)
 891	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
 892	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
 893	la	%r1,__LC_SAVE_AREA
 894	ch	%r12,BASED(.L0x020)	# old psw addr == __LC_SVC_OLD_PSW ?
 895	be	BASED(0f)
 896	ch	%r12,BASED(.L0x028)	# old psw addr == __LC_PGM_OLD_PSW ?
 897	be	BASED(0f)
 898	la	%r1,__LC_SAVE_AREA+16
 8990:	mvc	SP_R12(16,%r15),0(%r1)	# move %r12-%r15 to stack
 900	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain
 901	l	%r1,BASED(1f)		# branch to kernel_stack_overflow
 902	la	%r2,SP_PTREGS(%r15)	# load pt_regs
 903	br	%r1
 9041:	.long	kernel_stack_overflow
 905#endif
 906
 907cleanup_table_system_call:
 908	.long	system_call + 0x80000000, sysc_do_svc + 0x80000000
 909cleanup_table_sysc_tif:
 910	.long	sysc_tif + 0x80000000, sysc_restore + 0x80000000
 911cleanup_table_sysc_restore:
 912	.long	sysc_restore + 0x80000000, sysc_done + 0x80000000
 913cleanup_table_io_tif:
 914	.long	io_tif + 0x80000000, io_restore + 0x80000000
 915cleanup_table_io_restore:
 916	.long	io_restore + 0x80000000, io_done + 0x80000000
 917
 918cleanup_critical:
 919	clc	4(4,%r12),BASED(cleanup_table_system_call)
 920	bl	BASED(0f)
 921	clc	4(4,%r12),BASED(cleanup_table_system_call+4)
 922	bl	BASED(cleanup_system_call)
 9230:
 924	clc	4(4,%r12),BASED(cleanup_table_sysc_tif)
 925	bl	BASED(0f)
 926	clc	4(4,%r12),BASED(cleanup_table_sysc_tif+4)
 927	bl	BASED(cleanup_sysc_tif)
 9280:
 929	clc	4(4,%r12),BASED(cleanup_table_sysc_restore)
 930	bl	BASED(0f)
 931	clc	4(4,%r12),BASED(cleanup_table_sysc_restore+4)
 932	bl	BASED(cleanup_sysc_restore)
 9330:
 934	clc	4(4,%r12),BASED(cleanup_table_io_tif)
 935	bl	BASED(0f)
 936	clc	4(4,%r12),BASED(cleanup_table_io_tif+4)
 937	bl	BASED(cleanup_io_tif)
 9380:
 939	clc	4(4,%r12),BASED(cleanup_table_io_restore)
 940	bl	BASED(0f)
 941	clc	4(4,%r12),BASED(cleanup_table_io_restore+4)
 942	bl	BASED(cleanup_io_restore)
 9430:
 944	br	%r14
 945
 946cleanup_system_call:
 947	mvc	__LC_RETURN_PSW(8),0(%r12)
 948	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
 949	bh	BASED(0f)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 950	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
 951	c	%r12,BASED(.Lmck_old_psw)
 952	be	BASED(0f)
 953	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
 9540:	c	%r12,BASED(.Lmck_old_psw)
 955	la	%r12,__LC_SAVE_AREA+32
 956	be	BASED(0f)
 957	la	%r12,__LC_SAVE_AREA+16
 9580:	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8)
 959	bhe	BASED(cleanup_vtime)
 960	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
 961	bh	BASED(0f)
 962	mvc	__LC_SAVE_AREA(16),0(%r12)
 9630:	st	%r13,4(%r12)
 964	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
 965	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
 966	st	%r15,12(%r12)
 967	CREATE_STACK_FRAME __LC_SAVE_AREA
 968	mvc	SP_PSW(8,%r15),__LC_SVC_OLD_PSW
 969	mvc	SP_ILC(4,%r15),__LC_SVC_ILC
 970	mvc	0(4,%r12),__LC_THREAD_INFO
 971cleanup_vtime:
 972	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
 973	bhe	BASED(cleanup_stime)
 974	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
 975cleanup_stime:
 976	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+16)
 977	bh	BASED(cleanup_update)
 978	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
 979cleanup_update:
 980	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 981	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_system_call+4)
 982	la	%r12,__LC_RETURN_PSW
 983	br	%r14
 984cleanup_system_call_insn:
 985	.long	sysc_saveall + 0x80000000
 986	.long	system_call + 0x80000000
 987	.long	sysc_vtime + 0x80000000
 988	.long	sysc_stime + 0x80000000
 989	.long	sysc_update + 0x80000000
 990
 991cleanup_sysc_tif:
 992	mvc	__LC_RETURN_PSW(4),0(%r12)
 993	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_tif)
 994	la	%r12,__LC_RETURN_PSW
 995	br	%r14
 996
 997cleanup_sysc_restore:
 998	clc	4(4,%r12),BASED(cleanup_sysc_restore_insn)
 999	be	BASED(2f)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1000	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
1001	c	%r12,BASED(.Lmck_old_psw)
1002	be	BASED(0f)
1003	mvc	__LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
10040:	clc	4(4,%r12),BASED(cleanup_sysc_restore_insn+4)
1005	be	BASED(2f)
1006	mvc	__LC_RETURN_PSW(8),SP_PSW(%r15)
1007	c	%r12,BASED(.Lmck_old_psw)
1008	la	%r12,__LC_SAVE_AREA+32
1009	be	BASED(1f)
1010	la	%r12,__LC_SAVE_AREA+16
10111:	mvc	0(16,%r12),SP_R12(%r15)
1012	lm	%r0,%r11,SP_R0(%r15)
1013	l	%r15,SP_R15(%r15)
10142:	la	%r12,__LC_RETURN_PSW
1015	br	%r14
1016cleanup_sysc_restore_insn:
1017	.long	sysc_done - 4 + 0x80000000
1018	.long	sysc_done - 8 + 0x80000000
1019
1020cleanup_io_tif:
1021	mvc	__LC_RETURN_PSW(4),0(%r12)
1022	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_io_tif)
1023	la	%r12,__LC_RETURN_PSW
1024	br	%r14
1025
1026cleanup_io_restore:
1027	clc	4(4,%r12),BASED(cleanup_io_restore_insn)
1028	be	BASED(1f)
1029	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
1030	clc	4(4,%r12),BASED(cleanup_io_restore_insn+4)
1031	be	BASED(1f)
1032	mvc	__LC_RETURN_PSW(8),SP_PSW(%r15)
1033	mvc	__LC_SAVE_AREA+32(16),SP_R12(%r15)
1034	lm	%r0,%r11,SP_R0(%r15)
1035	l	%r15,SP_R15(%r15)
10361:	la	%r12,__LC_RETURN_PSW
1037	br	%r14
1038cleanup_io_restore_insn:
1039	.long	io_done - 4 + 0x80000000
1040	.long	io_done - 8 + 0x80000000
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1041
1042/*
1043 * Integer constants
1044 */
1045		.align	4
1046.Lc_spsize:	.long	SP_SIZE
1047.Lc_overhead:	.long	STACK_FRAME_OVERHEAD
1048.Lnr_syscalls:	.long	NR_syscalls
1049.L0x018:	.short	0x018
1050.L0x020:	.short	0x020
1051.L0x028:	.short	0x028
1052.L0x030:	.short	0x030
1053.L0x038:	.short	0x038
1054.Lc_1:		.long	1
1055
1056/*
1057 * Symbol constants
1058 */
1059.Ls390_mcck:	.long	s390_do_machine_check
1060.Ls390_handle_mcck:
1061		.long	s390_handle_mcck
1062.Lmck_old_psw:	.long	__LC_MCK_OLD_PSW
1063.Ldo_IRQ:	.long	do_IRQ
1064.Ldo_extint:	.long	do_extint
1065.Ldo_signal:	.long	do_signal
1066.Ldo_notify_resume:
1067		.long	do_notify_resume
1068.Lhandle_per:	.long	do_per_trap
1069.Ldo_execve:	.long	do_execve
1070.Lexecve_tail:	.long	execve_tail
1071.Ljump_table:	.long	pgm_check_table
1072.Lschedule:	.long	schedule
1073#ifdef CONFIG_PREEMPT
1074.Lpreempt_schedule_irq:
1075		.long	preempt_schedule_irq
1076#endif
1077.Ltrace_entry:	.long	do_syscall_trace_enter
1078.Ltrace_exit:	.long	do_syscall_trace_exit
1079.Lschedtail:	.long	schedule_tail
1080.Lsysc_table:	.long	sys_call_table
1081#ifdef CONFIG_TRACE_IRQFLAGS
1082.Ltrace_irq_on_caller:
1083		.long	trace_hardirqs_on_caller
1084.Ltrace_irq_off_caller:
1085		.long	trace_hardirqs_off_caller
1086#endif
1087#ifdef CONFIG_LOCKDEP
1088.Llockdep_sys_exit:
1089		.long	lockdep_sys_exit
1090#endif
1091.Lcritical_start:
1092		.long	__critical_start + 0x80000000
1093.Lcritical_end:
1094		.long	__critical_end + 0x80000000
1095.Lcleanup_critical:
1096		.long	cleanup_critical
1097
1098		.section .rodata, "a"
1099#define SYSCALL(esa,esame,emu)	.long esa
1100	.globl	sys_call_table
1101sys_call_table:
1102#include "syscalls.S"
1103#undef SYSCALL