Text file
src/runtime/sys_freebsd_386.s
1 // Copyright 2009 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 sys.stuff for 386, FreeBSD
6 // /usr/src/sys/kern/syscalls.master for syscall numbers.
7 //
8
9 #include "go_asm.h"
10 #include "go_tls.h"
11 #include "textflag.h"
12
13 #define CLOCK_REALTIME 0
14 #define CLOCK_MONOTONIC 4
15 #define FD_CLOEXEC 1
16 #define F_SETFD 2
17
18 #define SYS_exit 1
19 #define SYS_read 3
20 #define SYS_write 4
21 #define SYS_open 5
22 #define SYS_close 6
23 #define SYS_getpid 20
24 #define SYS_kill 37
25 #define SYS_sigaltstack 53
26 #define SYS_munmap 73
27 #define SYS_madvise 75
28 #define SYS_setitimer 83
29 #define SYS_fcntl 92
30 #define SYS_sysarch 165
31 #define SYS___sysctl 202
32 #define SYS_clock_gettime 232
33 #define SYS_nanosleep 240
34 #define SYS_sched_yield 331
35 #define SYS_sigprocmask 340
36 #define SYS_kqueue 362
37 #define SYS_sigaction 416
38 #define SYS_sigreturn 417
39 #define SYS_thr_exit 431
40 #define SYS_thr_self 432
41 #define SYS_thr_kill 433
42 #define SYS__umtx_op 454
43 #define SYS_thr_new 455
44 #define SYS_mmap 477
45 #define SYS_cpuset_getaffinity 487
46 #define SYS_pipe2 542
47 #define SYS_kevent 560
48
49 TEXT runtime·sys_umtx_op(SB),NOSPLIT,$-4
50 MOVL $SYS__umtx_op, AX
51 INT $0x80
52 JAE 2(PC)
53 NEGL AX
54 MOVL AX, ret+20(FP)
55 RET
56
57 TEXT runtime·thr_new(SB),NOSPLIT,$-4
58 MOVL $SYS_thr_new, AX
59 INT $0x80
60 JAE 2(PC)
61 NEGL AX
62 MOVL AX, ret+8(FP)
63 RET
64
65 // Called by OS using C ABI.
66 TEXT runtime·thr_start(SB),NOSPLIT,$0
67 NOP SP // tell vet SP changed - stop checking offsets
68 MOVL 4(SP), AX // m
69 MOVL m_g0(AX), BX
70 LEAL m_tls(AX), BP
71 MOVL m_id(AX), DI
72 ADDL $7, DI
73 PUSHAL
74 PUSHL $32
75 PUSHL BP
76 PUSHL DI
77 CALL runtime·setldt(SB)
78 POPL AX
79 POPL AX
80 POPL AX
81 POPAL
82 get_tls(CX)
83 MOVL BX, g(CX)
84
85 MOVL AX, g_m(BX)
86 CALL runtime·stackcheck(SB) // smashes AX
87 CALL runtime·mstart(SB)
88
89 MOVL 0, AX // crash (not reached)
90
91 // Exit the entire program (like C exit)
92 TEXT runtime·exit(SB),NOSPLIT,$-4
93 MOVL $SYS_exit, AX
94 INT $0x80
95 MOVL $0xf1, 0xf1 // crash
96 RET
97
98 GLOBL exitStack<>(SB),RODATA,$8
99 DATA exitStack<>+0x00(SB)/4, $0
100 DATA exitStack<>+0x04(SB)/4, $0
101
102 // func exitThread(wait *atomic.Uint32)
103 TEXT runtime·exitThread(SB),NOSPLIT,$0-4
104 MOVL wait+0(FP), AX
105 // We're done using the stack.
106 MOVL $0, (AX)
107 // thr_exit takes a single pointer argument, which it expects
108 // on the stack. We want to pass 0, so switch over to a fake
109 // stack of 0s. It won't write to the stack.
110 MOVL $exitStack<>(SB), SP
111 MOVL $SYS_thr_exit, AX
112 INT $0x80
113 MOVL $0xf1, 0xf1 // crash
114 JMP 0(PC)
115
116 TEXT runtime·open(SB),NOSPLIT,$-4
117 MOVL $SYS_open, AX
118 INT $0x80
119 JAE 2(PC)
120 MOVL $-1, AX
121 MOVL AX, ret+12(FP)
122 RET
123
124 TEXT runtime·closefd(SB),NOSPLIT,$-4
125 MOVL $SYS_close, AX
126 INT $0x80
127 JAE 2(PC)
128 MOVL $-1, AX
129 MOVL AX, ret+4(FP)
130 RET
131
132 TEXT runtime·read(SB),NOSPLIT,$-4
133 MOVL $SYS_read, AX
134 INT $0x80
135 JAE 2(PC)
136 NEGL AX // caller expects negative errno
137 MOVL AX, ret+12(FP)
138 RET
139
140 // func pipe2(flags int32) (r, w int32, errno int32)
141 TEXT runtime·pipe2(SB),NOSPLIT,$12-16
142 MOVL $SYS_pipe2, AX
143 LEAL r+4(FP), BX
144 MOVL BX, 4(SP)
145 MOVL flags+0(FP), BX
146 MOVL BX, 8(SP)
147 INT $0x80
148 JAE 2(PC)
149 NEGL AX
150 MOVL AX, errno+12(FP)
151 RET
152
153 TEXT runtime·write1(SB),NOSPLIT,$-4
154 MOVL $SYS_write, AX
155 INT $0x80
156 JAE 2(PC)
157 NEGL AX // caller expects negative errno
158 MOVL AX, ret+12(FP)
159 RET
160
161 TEXT runtime·thr_self(SB),NOSPLIT,$8-4
162 // thr_self(&0(FP))
163 LEAL ret+0(FP), AX
164 MOVL AX, 4(SP)
165 MOVL $SYS_thr_self, AX
166 INT $0x80
167 RET
168
169 TEXT runtime·thr_kill(SB),NOSPLIT,$-4
170 // thr_kill(tid, sig)
171 MOVL $SYS_thr_kill, AX
172 INT $0x80
173 RET
174
175 TEXT runtime·raiseproc(SB),NOSPLIT,$16
176 // getpid
177 MOVL $SYS_getpid, AX
178 INT $0x80
179 // kill(self, sig)
180 MOVL AX, 4(SP)
181 MOVL sig+0(FP), AX
182 MOVL AX, 8(SP)
183 MOVL $SYS_kill, AX
184 INT $0x80
185 RET
186
187 TEXT runtime·mmap(SB),NOSPLIT,$32
188 LEAL addr+0(FP), SI
189 LEAL 4(SP), DI
190 CLD
191 MOVSL
192 MOVSL
193 MOVSL
194 MOVSL
195 MOVSL
196 MOVSL
197 MOVL $0, AX // top 32 bits of file offset
198 STOSL
199 MOVL $SYS_mmap, AX
200 INT $0x80
201 JAE ok
202 MOVL $0, p+24(FP)
203 MOVL AX, err+28(FP)
204 RET
205 ok:
206 MOVL AX, p+24(FP)
207 MOVL $0, err+28(FP)
208 RET
209
210 TEXT runtime·munmap(SB),NOSPLIT,$-4
211 MOVL $SYS_munmap, AX
212 INT $0x80
213 JAE 2(PC)
214 MOVL $0xf1, 0xf1 // crash
215 RET
216
217 TEXT runtime·madvise(SB),NOSPLIT,$-4
218 MOVL $SYS_madvise, AX
219 INT $0x80
220 JAE 2(PC)
221 MOVL $-1, AX
222 MOVL AX, ret+12(FP)
223 RET
224
225 TEXT runtime·setitimer(SB), NOSPLIT, $-4
226 MOVL $SYS_setitimer, AX
227 INT $0x80
228 RET
229
230 // func fallback_walltime() (sec int64, nsec int32)
231 TEXT runtime·fallback_walltime(SB), NOSPLIT, $32-12
232 MOVL $SYS_clock_gettime, AX
233 LEAL 12(SP), BX
234 MOVL $CLOCK_REALTIME, 4(SP)
235 MOVL BX, 8(SP)
236 INT $0x80
237 MOVL 12(SP), AX // sec
238 MOVL 16(SP), BX // nsec
239
240 // sec is in AX, nsec in BX
241 MOVL AX, sec_lo+0(FP)
242 MOVL $0, sec_hi+4(FP)
243 MOVL BX, nsec+8(FP)
244 RET
245
246 // func fallback_nanotime() int64
247 TEXT runtime·fallback_nanotime(SB), NOSPLIT, $32-8
248 MOVL $SYS_clock_gettime, AX
249 LEAL 12(SP), BX
250 MOVL $CLOCK_MONOTONIC, 4(SP)
251 MOVL BX, 8(SP)
252 INT $0x80
253 MOVL 12(SP), AX // sec
254 MOVL 16(SP), BX // nsec
255
256 // sec is in AX, nsec in BX
257 // convert to DX:AX nsec
258 MOVL $1000000000, CX
259 MULL CX
260 ADDL BX, AX
261 ADCL $0, DX
262
263 MOVL AX, ret_lo+0(FP)
264 MOVL DX, ret_hi+4(FP)
265 RET
266
267
268 TEXT runtime·asmSigaction(SB),NOSPLIT,$-4
269 MOVL $SYS_sigaction, AX
270 INT $0x80
271 MOVL AX, ret+12(FP)
272 RET
273
274 TEXT runtime·sigfwd(SB),NOSPLIT,$12-16
275 MOVL fn+0(FP), AX
276 MOVL sig+4(FP), BX
277 MOVL info+8(FP), CX
278 MOVL ctx+12(FP), DX
279 MOVL SP, SI
280 SUBL $32, SP
281 ANDL $~15, SP // align stack: handler might be a C function
282 MOVL BX, 0(SP)
283 MOVL CX, 4(SP)
284 MOVL DX, 8(SP)
285 MOVL SI, 12(SP) // save SI: handler might be a Go function
286 CALL AX
287 MOVL 12(SP), AX
288 MOVL AX, SP
289 RET
290
291 // Called by OS using C ABI.
292 TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$12
293 NOP SP // tell vet SP changed - stop checking offsets
294 MOVL 16(SP), BX // signo
295 MOVL BX, 0(SP)
296 MOVL 20(SP), BX // info
297 MOVL BX, 4(SP)
298 MOVL 24(SP), BX // context
299 MOVL BX, 8(SP)
300 CALL runtime·sigtrampgo(SB)
301
302 // call sigreturn
303 MOVL 24(SP), AX // context
304 MOVL $0, 0(SP) // syscall gap
305 MOVL AX, 4(SP)
306 MOVL $SYS_sigreturn, AX
307 INT $0x80
308 MOVL $0xf1, 0xf1 // crash
309 RET
310
311 TEXT runtime·sigaltstack(SB),NOSPLIT,$0
312 MOVL $SYS_sigaltstack, AX
313 INT $0x80
314 JAE 2(PC)
315 MOVL $0xf1, 0xf1 // crash
316 RET
317
318 TEXT runtime·usleep(SB),NOSPLIT,$20
319 MOVL $0, DX
320 MOVL usec+0(FP), AX
321 MOVL $1000000, CX
322 DIVL CX
323 MOVL AX, 12(SP) // tv_sec
324 MOVL $1000, AX
325 MULL DX
326 MOVL AX, 16(SP) // tv_nsec
327
328 MOVL $0, 0(SP)
329 LEAL 12(SP), AX
330 MOVL AX, 4(SP) // arg 1 - rqtp
331 MOVL $0, 8(SP) // arg 2 - rmtp
332 MOVL $SYS_nanosleep, AX
333 INT $0x80
334 RET
335
336 /*
337 descriptor entry format for system call
338 is the native machine format, ugly as it is:
339
340 2-byte limit
341 3-byte base
342 1-byte: 0x80=present, 0x60=dpl<<5, 0x1F=type
343 1-byte: 0x80=limit is *4k, 0x40=32-bit operand size,
344 0x0F=4 more bits of limit
345 1 byte: 8 more bits of base
346
347 int i386_get_ldt(int, union ldt_entry *, int);
348 int i386_set_ldt(int, const union ldt_entry *, int);
349
350 */
351
352 // setldt(int entry, int address, int limit)
353 TEXT runtime·setldt(SB),NOSPLIT,$32
354 MOVL base+4(FP), BX
355 // see comment in sys_linux_386.s; freebsd is similar
356 ADDL $0x4, BX
357
358 // set up data_desc
359 LEAL 16(SP), AX // struct data_desc
360 MOVL $0, 0(AX)
361 MOVL $0, 4(AX)
362
363 MOVW BX, 2(AX)
364 SHRL $16, BX
365 MOVB BX, 4(AX)
366 SHRL $8, BX
367 MOVB BX, 7(AX)
368
369 MOVW $0xffff, 0(AX)
370 MOVB $0xCF, 6(AX) // 32-bit operand, 4k limit unit, 4 more bits of limit
371
372 MOVB $0xF2, 5(AX) // r/w data descriptor, dpl=3, present
373
374 // call i386_set_ldt(entry, desc, 1)
375 MOVL $0xffffffff, 0(SP) // auto-allocate entry and return in AX
376 MOVL AX, 4(SP)
377 MOVL $1, 8(SP)
378 CALL i386_set_ldt<>(SB)
379
380 // compute segment selector - (entry*8+7)
381 SHLL $3, AX
382 ADDL $7, AX
383 MOVW AX, GS
384 RET
385
386 TEXT i386_set_ldt<>(SB),NOSPLIT,$16
387 LEAL args+0(FP), AX // 0(FP) == 4(SP) before SP got moved
388 MOVL $0, 0(SP) // syscall gap
389 MOVL $1, 4(SP)
390 MOVL AX, 8(SP)
391 MOVL $SYS_sysarch, AX
392 INT $0x80
393 JAE 2(PC)
394 INT $3
395 RET
396
397 TEXT runtime·sysctl(SB),NOSPLIT,$28
398 LEAL mib+0(FP), SI
399 LEAL 4(SP), DI
400 CLD
401 MOVSL // arg 1 - name
402 MOVSL // arg 2 - namelen
403 MOVSL // arg 3 - oldp
404 MOVSL // arg 4 - oldlenp
405 MOVSL // arg 5 - newp
406 MOVSL // arg 6 - newlen
407 MOVL $SYS___sysctl, AX
408 INT $0x80
409 JAE 4(PC)
410 NEGL AX
411 MOVL AX, ret+24(FP)
412 RET
413 MOVL $0, AX
414 MOVL AX, ret+24(FP)
415 RET
416
417 TEXT runtime·osyield(SB),NOSPLIT,$-4
418 MOVL $SYS_sched_yield, AX
419 INT $0x80
420 RET
421
422 TEXT runtime·sigprocmask(SB),NOSPLIT,$16
423 MOVL $0, 0(SP) // syscall gap
424 MOVL how+0(FP), AX // arg 1 - how
425 MOVL AX, 4(SP)
426 MOVL new+4(FP), AX
427 MOVL AX, 8(SP) // arg 2 - set
428 MOVL old+8(FP), AX
429 MOVL AX, 12(SP) // arg 3 - oset
430 MOVL $SYS_sigprocmask, AX
431 INT $0x80
432 JAE 2(PC)
433 MOVL $0xf1, 0xf1 // crash
434 RET
435
436 // int32 runtime·kqueue(void);
437 TEXT runtime·kqueue(SB),NOSPLIT,$0
438 MOVL $SYS_kqueue, AX
439 INT $0x80
440 JAE 2(PC)
441 NEGL AX
442 MOVL AX, ret+0(FP)
443 RET
444
445 // int32 runtime·kevent(int kq, Kevent *changelist, int nchanges, Kevent *eventlist, int nevents, Timespec *timeout);
446 TEXT runtime·kevent(SB),NOSPLIT,$0
447 MOVL $SYS_kevent, AX
448 INT $0x80
449 JAE 2(PC)
450 NEGL AX
451 MOVL AX, ret+24(FP)
452 RET
453
454 // int32 runtime·closeonexec(int32 fd);
455 TEXT runtime·closeonexec(SB),NOSPLIT,$32
456 MOVL $SYS_fcntl, AX
457 // 0(SP) is where the caller PC would be; kernel skips it
458 MOVL fd+0(FP), BX
459 MOVL BX, 4(SP) // fd
460 MOVL $F_SETFD, 8(SP)
461 MOVL $FD_CLOEXEC, 12(SP)
462 INT $0x80
463 JAE 2(PC)
464 NEGL AX
465 RET
466
467 // func cpuset_getaffinity(level int, which int, id int64, size int, mask *byte) int32
468 TEXT runtime·cpuset_getaffinity(SB), NOSPLIT, $0-28
469 MOVL $SYS_cpuset_getaffinity, AX
470 INT $0x80
471 JAE 2(PC)
472 NEGL AX
473 MOVL AX, ret+24(FP)
474 RET
475
476 GLOBL runtime·tlsoffset(SB),NOPTR,$4
477
View as plain text