1// Copyright 2016 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// System calls and other system stuff for Linux s390x; see
6// /usr/include/asm/unistd.h for the syscall number definitions.
7
8#include "go_asm.h"
9#include "go_tls.h"
10#include "textflag.h"
11
12#define SYS_exit                  1
13#define SYS_read                  3
14#define SYS_write                 4
15#define SYS_open                  5
16#define SYS_close                 6
17#define SYS_getpid               20
18#define SYS_kill                 37
19#define SYS_brk			 45
20#define SYS_mmap                 90
21#define SYS_munmap               91
22#define SYS_setitimer           104
23#define SYS_clone               120
24#define SYS_sched_yield         158
25#define SYS_nanosleep           162
26#define SYS_rt_sigreturn        173
27#define SYS_rt_sigaction        174
28#define SYS_rt_sigprocmask      175
29#define SYS_sigaltstack         186
30#define SYS_madvise             219
31#define SYS_mincore             218
32#define SYS_gettid              236
33#define SYS_futex               238
34#define SYS_sched_getaffinity   240
35#define SYS_tgkill              241
36#define SYS_exit_group          248
37#define SYS_timer_create        254
38#define SYS_timer_settime       255
39#define SYS_timer_delete        258
40#define SYS_clock_gettime       260
41#define SYS_pipe2		325
42
43TEXT runtime·exit(SB),NOSPLIT|NOFRAME,$0-4
44	MOVW	code+0(FP), R2
45	MOVW	$SYS_exit_group, R1
46	SYSCALL
47	RET
48
49// func exitThread(wait *atomic.Uint32)
50TEXT runtime·exitThread(SB),NOSPLIT|NOFRAME,$0-8
51	MOVD	wait+0(FP), R1
52	// We're done using the stack.
53	MOVW	$0, R2
54	MOVW	R2, (R1)
55	MOVW	$0, R2	// exit code
56	MOVW	$SYS_exit, R1
57	SYSCALL
58	JMP	0(PC)
59
60TEXT runtime·open(SB),NOSPLIT|NOFRAME,$0-20
61	MOVD	name+0(FP), R2
62	MOVW	mode+8(FP), R3
63	MOVW	perm+12(FP), R4
64	MOVW	$SYS_open, R1
65	SYSCALL
66	MOVD	$-4095, R3
67	CMPUBLT	R2, R3, 2(PC)
68	MOVW	$-1, R2
69	MOVW	R2, ret+16(FP)
70	RET
71
72TEXT runtime·closefd(SB),NOSPLIT|NOFRAME,$0-12
73	MOVW	fd+0(FP), R2
74	MOVW	$SYS_close, R1
75	SYSCALL
76	MOVD	$-4095, R3
77	CMPUBLT	R2, R3, 2(PC)
78	MOVW	$-1, R2
79	MOVW	R2, ret+8(FP)
80	RET
81
82TEXT runtime·write1(SB),NOSPLIT|NOFRAME,$0-28
83	MOVD	fd+0(FP), R2
84	MOVD	p+8(FP), R3
85	MOVW	n+16(FP), R4
86	MOVW	$SYS_write, R1
87	SYSCALL
88	MOVW	R2, ret+24(FP)
89	RET
90
91TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
92	MOVW	fd+0(FP), R2
93	MOVD	p+8(FP), R3
94	MOVW	n+16(FP), R4
95	MOVW	$SYS_read, R1
96	SYSCALL
97	MOVW	R2, ret+24(FP)
98	RET
99
100// func pipe2() (r, w int32, errno int32)
101TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
102	MOVD	$r+8(FP), R2
103	MOVW	flags+0(FP), R3
104	MOVW	$SYS_pipe2, R1
105	SYSCALL
106	MOVW	R2, errno+16(FP)
107	RET
108
109TEXT runtime·usleep(SB),NOSPLIT,$16-4
110	MOVW	usec+0(FP), R2
111	MOVD	R2, R4
112	MOVW	$1000000, R3
113	DIVD	R3, R2
114	MOVD	R2, 8(R15)
115	MOVW	$1000, R3
116	MULLD	R2, R3
117	SUB	R3, R4
118	MOVD	R4, 16(R15)
119
120	// nanosleep(&ts, 0)
121	ADD	$8, R15, R2
122	MOVW	$0, R3
123	MOVW	$SYS_nanosleep, R1
124	SYSCALL
125	RET
126
127TEXT runtime·gettid(SB),NOSPLIT,$0-4
128	MOVW	$SYS_gettid, R1
129	SYSCALL
130	MOVW	R2, ret+0(FP)
131	RET
132
133TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0
134	MOVW	$SYS_getpid, R1
135	SYSCALL
136	MOVW	R2, R10
137	MOVW	$SYS_gettid, R1
138	SYSCALL
139	MOVW	R2, R3	// arg 2 tid
140	MOVW	R10, R2	// arg 1 pid
141	MOVW	sig+0(FP), R4	// arg 2
142	MOVW	$SYS_tgkill, R1
143	SYSCALL
144	RET
145
146TEXT runtime·raiseproc(SB),NOSPLIT|NOFRAME,$0
147	MOVW	$SYS_getpid, R1
148	SYSCALL
149	MOVW	R2, R2	// arg 1 pid
150	MOVW	sig+0(FP), R3	// arg 2
151	MOVW	$SYS_kill, R1
152	SYSCALL
153	RET
154
155TEXT ·getpid(SB),NOSPLIT|NOFRAME,$0-8
156	MOVW	$SYS_getpid, R1
157	SYSCALL
158	MOVD	R2, ret+0(FP)
159	RET
160
161TEXT ·tgkill(SB),NOSPLIT|NOFRAME,$0-24
162	MOVD	tgid+0(FP), R2
163	MOVD	tid+8(FP), R3
164	MOVD	sig+16(FP), R4
165	MOVW	$SYS_tgkill, R1
166	SYSCALL
167	RET
168
169TEXT runtime·setitimer(SB),NOSPLIT|NOFRAME,$0-24
170	MOVW	mode+0(FP), R2
171	MOVD	new+8(FP), R3
172	MOVD	old+16(FP), R4
173	MOVW	$SYS_setitimer, R1
174	SYSCALL
175	RET
176
177TEXT runtime·timer_create(SB),NOSPLIT|NOFRAME,$0-28
178	MOVW	clockid+0(FP), R2
179	MOVD	sevp+8(FP), R3
180	MOVD	timerid+16(FP), R4
181	MOVW	$SYS_timer_create, R1
182	SYSCALL
183	MOVW	R2, ret+24(FP)
184	RET
185
186TEXT runtime·timer_settime(SB),NOSPLIT|NOFRAME,$0-28
187	MOVW	timerid+0(FP), R2
188	MOVW	flags+4(FP), R3
189	MOVD	new+8(FP), R4
190	MOVD	old+16(FP), R5
191	MOVW	$SYS_timer_settime, R1
192	SYSCALL
193	MOVW	R2, ret+24(FP)
194	RET
195
196TEXT runtime·timer_delete(SB),NOSPLIT|NOFRAME,$0-12
197	MOVW	timerid+0(FP), R2
198	MOVW	$SYS_timer_delete, R1
199	SYSCALL
200	MOVW	R2, ret+8(FP)
201	RET
202
203TEXT runtime·mincore(SB),NOSPLIT|NOFRAME,$0-28
204	MOVD	addr+0(FP), R2
205	MOVD	n+8(FP), R3
206	MOVD	dst+16(FP), R4
207	MOVW	$SYS_mincore, R1
208	SYSCALL
209	MOVW	R2, ret+24(FP)
210	RET
211
212// func walltime() (sec int64, nsec int32)
213TEXT runtime·walltime(SB),NOSPLIT,$32-12
214	MOVW	$0, R2			// CLOCK_REALTIME
215	MOVD	R15, R7			// Backup stack pointer
216
217	MOVD	g_m(g), R6		//m
218
219	MOVD	runtime·vdsoClockgettimeSym(SB), R9	// Check for VDSO availability
220	CMPBEQ	R9, $0, fallback
221
222	MOVD	m_vdsoPC(R6), R4
223	MOVD	R4, 16(R15)
224	MOVD	m_vdsoSP(R6), R4
225	MOVD	R4, 24(R15)
226
227	MOVD	R14, R8 		// Backup return address
228	MOVD	$sec+0(FP), R4 	// return parameter caller
229
230	MOVD	R8, m_vdsoPC(R6)
231	MOVD	R4, m_vdsoSP(R6)
232
233	MOVD	m_curg(R6), R5
234	CMP		g, R5
235	BNE		noswitch
236
237	MOVD	m_g0(R6), R4
238	MOVD	(g_sched+gobuf_sp)(R4), R15	// Set SP to g0 stack
239
240noswitch:
241	SUB		$16, R15		// reserve 2x 8 bytes for parameters
242	MOVD	$~7, R4			// align to 8 bytes because of gcc ABI
243	AND		R4, R15
244	MOVD	R15, R3			// R15 needs to be in R3 as expected by kernel_clock_gettime
245
246	MOVB	runtime·iscgo(SB),R12
247	CMPBNE	R12, $0, nosaveg
248
249	MOVD	m_gsignal(R6), R12	// g.m.gsignal
250	CMPBEQ	R12, $0, nosaveg
251
252	CMPBEQ	g, R12, nosaveg
253	MOVD	(g_stack+stack_lo)(R12), R12 // g.m.gsignal.stack.lo
254	MOVD	g, (R12)
255
256	BL	R9 // to vdso lookup
257
258	MOVD	$0, (R12)
259
260	JMP	finish
261
262nosaveg:
263	BL	R9					// to vdso lookup
264
265finish:
266	MOVD	0(R15), R3		// sec
267	MOVD	8(R15), R5		// nsec
268	MOVD	R7, R15			// Restore SP
269
270	// Restore vdsoPC, vdsoSP
271	// We don't worry about being signaled between the two stores.
272	// If we are not in a signal handler, we'll restore vdsoSP to 0,
273	// and no one will care about vdsoPC. If we are in a signal handler,
274	// we cannot receive another signal.
275	MOVD	24(R15), R12
276	MOVD	R12, m_vdsoSP(R6)
277	MOVD	16(R15), R12
278	MOVD	R12, m_vdsoPC(R6)
279
280return:
281	// sec is in R3, nsec in R5
282	// return nsec in R3
283	MOVD	R3, sec+0(FP)
284	MOVW	R5, nsec+8(FP)
285	RET
286
287	// Syscall fallback
288fallback:
289	MOVD	$tp-16(SP), R3
290	MOVW	$SYS_clock_gettime, R1
291	SYSCALL
292	LMG		tp-16(SP), R2, R3
293	// sec is in R2, nsec in R3
294	MOVD	R2, sec+0(FP)
295	MOVW	R3, nsec+8(FP)
296	RET
297
298TEXT runtime·nanotime1(SB),NOSPLIT,$32-8
299	MOVW	$1, R2			// CLOCK_MONOTONIC
300
301	MOVD	R15, R7			// Backup stack pointer
302
303	MOVD	g_m(g), R6		//m
304
305	MOVD	runtime·vdsoClockgettimeSym(SB), R9	// Check for VDSO availability
306	CMPBEQ	R9, $0, fallback
307
308	MOVD	m_vdsoPC(R6), R4
309	MOVD	R4, 16(R15)
310	MOVD	m_vdsoSP(R6), R4
311	MOVD	R4, 24(R15)
312
313	MOVD	R14, R8			// Backup return address
314	MOVD	$ret+0(FP), R4	// caller's SP
315
316	MOVD	R8, m_vdsoPC(R6)
317	MOVD	R4, m_vdsoSP(R6)
318
319	MOVD	m_curg(R6), R5
320	CMP		g, R5
321	BNE		noswitch
322
323	MOVD	m_g0(R6), R4
324	MOVD	(g_sched+gobuf_sp)(R4), R15	// Set SP to g0 stack
325
326noswitch:
327	SUB		$16, R15		// reserve 2x 8 bytes for parameters
328	MOVD	$~7, R4			// align to 8 bytes because of gcc ABI
329	AND		R4, R15
330	MOVD	R15, R3			// R15 needs to be in R3 as expected by kernel_clock_gettime
331
332	MOVB	runtime·iscgo(SB),R12
333	CMPBNE	R12, $0, nosaveg
334
335	MOVD	m_gsignal(R6), R12	// g.m.gsignal
336	CMPBEQ	R12, $0, nosaveg
337
338	CMPBEQ	g, R12, nosaveg
339	MOVD	(g_stack+stack_lo)(R12), R12	// g.m.gsignal.stack.lo
340	MOVD	g, (R12)
341
342	BL	R9 					// to vdso lookup
343
344	MOVD $0, (R12)
345
346	JMP	finish
347
348nosaveg:
349	BL	R9					// to vdso lookup
350
351finish:
352	MOVD	0(R15), R3		// sec
353	MOVD	8(R15), R5		// nsec
354	MOVD	R7, R15			// Restore SP
355
356	// Restore vdsoPC, vdsoSP
357	// We don't worry about being signaled between the two stores.
358	// If we are not in a signal handler, we'll restore vdsoSP to 0,
359	// and no one will care about vdsoPC. If we are in a signal handler,
360	// we cannot receive another signal.
361
362	MOVD	24(R15), R12
363	MOVD	R12, m_vdsoSP(R6)
364	MOVD	16(R15), R12
365	MOVD	R12, m_vdsoPC(R6)
366
367return:
368	// sec is in R3, nsec in R5
369	// return nsec in R3
370	MULLD	$1000000000, R3
371	ADD		R5, R3
372	MOVD	R3, ret+0(FP)
373	RET
374
375	// Syscall fallback
376fallback:
377	MOVD	$tp-16(SP), R3
378	MOVD	$SYS_clock_gettime, R1
379	SYSCALL
380	LMG		tp-16(SP), R2, R3
381	MOVD	R3, R5
382	MOVD	R2, R3
383	JMP	return
384
385TEXT runtime·rtsigprocmask(SB),NOSPLIT|NOFRAME,$0-28
386	MOVW	how+0(FP), R2
387	MOVD	new+8(FP), R3
388	MOVD	old+16(FP), R4
389	MOVW	size+24(FP), R5
390	MOVW	$SYS_rt_sigprocmask, R1
391	SYSCALL
392	MOVD	$-4095, R3
393	CMPUBLT	R2, R3, 2(PC)
394	MOVD	R0, 0(R0) // crash
395	RET
396
397TEXT runtime·rt_sigaction(SB),NOSPLIT|NOFRAME,$0-36
398	MOVD	sig+0(FP), R2
399	MOVD	new+8(FP), R3
400	MOVD	old+16(FP), R4
401	MOVD	size+24(FP), R5
402	MOVW	$SYS_rt_sigaction, R1
403	SYSCALL
404	MOVW	R2, ret+32(FP)
405	RET
406
407TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
408	MOVW	sig+8(FP), R2
409	MOVD	info+16(FP), R3
410	MOVD	ctx+24(FP), R4
411	MOVD	fn+0(FP), R5
412	BL	R5
413	RET
414
415TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$64
416	// initialize essential registers (just in case)
417	XOR	R0, R0
418
419	// this might be called in external code context,
420	// where g is not set.
421	MOVB	runtime·iscgo(SB), R6
422	CMPBEQ	R6, $0, 2(PC)
423	BL	runtime·load_g(SB)
424
425	MOVW	R2, 8(R15)
426	MOVD	R3, 16(R15)
427	MOVD	R4, 24(R15)
428	MOVD	$runtime·sigtrampgo(SB), R5
429	BL	R5
430	RET
431
432TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
433	BR	runtime·sigtramp(SB)
434
435// func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) unsafe.Pointer
436TEXT runtime·mmap(SB),NOSPLIT,$48-48
437	MOVD	addr+0(FP), R2
438	MOVD	n+8(FP), R3
439	MOVW	prot+16(FP), R4
440	MOVW	flags+20(FP), R5
441	MOVW	fd+24(FP), R6
442	MOVWZ	off+28(FP), R7
443
444	// s390x uses old_mmap, so the arguments need to be placed into
445	// a struct and a pointer to the struct passed to mmap.
446	MOVD	R2, addr-48(SP)
447	MOVD	R3, n-40(SP)
448	MOVD	R4, prot-32(SP)
449	MOVD	R5, flags-24(SP)
450	MOVD	R6, fd-16(SP)
451	MOVD	R7, off-8(SP)
452
453	MOVD	$addr-48(SP), R2
454	MOVW	$SYS_mmap, R1
455	SYSCALL
456	MOVD	$-4095, R3
457	CMPUBLT	R2, R3, ok
458	NEG	R2
459	MOVD	$0, p+32(FP)
460	MOVD	R2, err+40(FP)
461	RET
462ok:
463	MOVD	R2, p+32(FP)
464	MOVD	$0, err+40(FP)
465	RET
466
467TEXT runtime·munmap(SB),NOSPLIT|NOFRAME,$0
468	MOVD	addr+0(FP), R2
469	MOVD	n+8(FP), R3
470	MOVW	$SYS_munmap, R1
471	SYSCALL
472	MOVD	$-4095, R3
473	CMPUBLT	R2, R3, 2(PC)
474	MOVD	R0, 0(R0) // crash
475	RET
476
477TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0
478	MOVD	addr+0(FP), R2
479	MOVD	n+8(FP), R3
480	MOVW	flags+16(FP), R4
481	MOVW	$SYS_madvise, R1
482	SYSCALL
483	MOVW	R2, ret+24(FP)
484	RET
485
486// int64 futex(int32 *uaddr, int32 op, int32 val,
487//	struct timespec *timeout, int32 *uaddr2, int32 val2);
488TEXT runtime·futex(SB),NOSPLIT|NOFRAME,$0
489	MOVD	addr+0(FP), R2
490	MOVW	op+8(FP), R3
491	MOVW	val+12(FP), R4
492	MOVD	ts+16(FP), R5
493	MOVD	addr2+24(FP), R6
494	MOVW	val3+32(FP),  R7
495	MOVW	$SYS_futex, R1
496	SYSCALL
497	MOVW	R2, ret+40(FP)
498	RET
499
500// int32 clone(int32 flags, void *stk, M *mp, G *gp, void (*fn)(void));
501TEXT runtime·clone(SB),NOSPLIT|NOFRAME,$0
502	MOVW	flags+0(FP), R3
503	MOVD	stk+8(FP), R2
504
505	// Copy mp, gp, fn off parent stack for use by child.
506	// Careful: Linux system call clobbers ???.
507	MOVD	mp+16(FP), R7
508	MOVD	gp+24(FP), R8
509	MOVD	fn+32(FP), R9
510
511	MOVD	R7, -8(R2)
512	MOVD	R8, -16(R2)
513	MOVD	R9, -24(R2)
514	MOVD	$1234, R7
515	MOVD	R7, -32(R2)
516
517	SYSCALL $SYS_clone
518
519	// In parent, return.
520	CMPBEQ	R2, $0, 3(PC)
521	MOVW	R2, ret+40(FP)
522	RET
523
524	// In child, on new stack.
525	// initialize essential registers
526	XOR	R0, R0
527	MOVD	-32(R15), R7
528	CMP	R7, $1234
529	BEQ	2(PC)
530	MOVD	R0, 0(R0)
531
532	// Initialize m->procid to Linux tid
533	SYSCALL $SYS_gettid
534
535	MOVD	-24(R15), R9        // fn
536	MOVD	-16(R15), R8        // g
537	MOVD	-8(R15), R7         // m
538
539	CMPBEQ	R7, $0, nog
540	CMP	R8, $0
541	BEQ	nog
542
543	MOVD	R2, m_procid(R7)
544
545	// In child, set up new stack
546	MOVD	R7, g_m(R8)
547	MOVD	R8, g
548	//CALL	runtime·stackcheck(SB)
549
550nog:
551	// Call fn
552	BL	R9
553
554	// It shouldn't return.	 If it does, exit that thread.
555	MOVW	$111, R2
556	MOVW	$SYS_exit, R1
557	SYSCALL
558	BR	-2(PC)	// keep exiting
559
560TEXT runtime·sigaltstack(SB),NOSPLIT|NOFRAME,$0
561	MOVD	new+0(FP), R2
562	MOVD	old+8(FP), R3
563	MOVW	$SYS_sigaltstack, R1
564	SYSCALL
565	MOVD	$-4095, R3
566	CMPUBLT	R2, R3, 2(PC)
567	MOVD	R0, 0(R0) // crash
568	RET
569
570TEXT runtime·osyield(SB),NOSPLIT|NOFRAME,$0
571	MOVW	$SYS_sched_yield, R1
572	SYSCALL
573	RET
574
575TEXT runtime·sched_getaffinity(SB),NOSPLIT|NOFRAME,$0
576	MOVD	pid+0(FP), R2
577	MOVD	len+8(FP), R3
578	MOVD	buf+16(FP), R4
579	MOVW	$SYS_sched_getaffinity, R1
580	SYSCALL
581	MOVW	R2, ret+24(FP)
582	RET
583
584// func sbrk0() uintptr
585TEXT runtime·sbrk0(SB),NOSPLIT|NOFRAME,$0-8
586	// Implemented as brk(NULL).
587	MOVD	$0, R2
588	MOVW	$SYS_brk, R1
589	SYSCALL
590	MOVD	R2, ret+0(FP)
591	RET
592
593TEXT runtime·access(SB),$0-20
594	MOVD	$0, 2(R0) // unimplemented, only needed for android; declared in stubs_linux.go
595	MOVW	R0, ret+16(FP)
596	RET
597
598TEXT runtime·connect(SB),$0-28
599	MOVD	$0, 2(R0) // unimplemented, only needed for android; declared in stubs_linux.go
600	MOVW	R0, ret+24(FP)
601	RET
602
603TEXT runtime·socket(SB),$0-20
604	MOVD	$0, 2(R0) // unimplemented, only needed for android; declared in stubs_linux.go
605	MOVW	R0, ret+16(FP)
606	RET
607