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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * arch/alpha/kernel/entry.S | |
3 | * | |
4 | * Kernel entry-points. | |
5 | */ | |
6 | ||
e2d5df93 | 7 | #include <asm/asm-offsets.h> |
1da177e4 LT |
8 | #include <asm/thread_info.h> |
9 | #include <asm/pal.h> | |
10 | #include <asm/errno.h> | |
11 | #include <asm/unistd.h> | |
12 | ||
13 | .text | |
14 | .set noat | |
15 | ||
16 | /* Stack offsets. */ | |
17 | #define SP_OFF 184 | |
18 | #define SWITCH_STACK_SIZE 320 | |
19 | ||
20 | /* | |
21 | * This defines the normal kernel pt-regs layout. | |
22 | * | |
23 | * regs 9-15 preserved by C code | |
24 | * regs 16-18 saved by PAL-code | |
25 | * regs 29-30 saved and set up by PAL-code | |
26 | * JRP - Save regs 16-18 in a special area of the stack, so that | |
27 | * the palcode-provided values are available to the signal handler. | |
28 | */ | |
29 | ||
30 | #define SAVE_ALL \ | |
31 | subq $sp, SP_OFF, $sp; \ | |
32 | stq $0, 0($sp); \ | |
33 | stq $1, 8($sp); \ | |
34 | stq $2, 16($sp); \ | |
35 | stq $3, 24($sp); \ | |
36 | stq $4, 32($sp); \ | |
37 | stq $28, 144($sp); \ | |
38 | lda $2, alpha_mv; \ | |
39 | stq $5, 40($sp); \ | |
40 | stq $6, 48($sp); \ | |
41 | stq $7, 56($sp); \ | |
42 | stq $8, 64($sp); \ | |
43 | stq $19, 72($sp); \ | |
44 | stq $20, 80($sp); \ | |
45 | stq $21, 88($sp); \ | |
46 | ldq $2, HAE_CACHE($2); \ | |
47 | stq $22, 96($sp); \ | |
48 | stq $23, 104($sp); \ | |
49 | stq $24, 112($sp); \ | |
50 | stq $25, 120($sp); \ | |
51 | stq $26, 128($sp); \ | |
52 | stq $27, 136($sp); \ | |
53 | stq $2, 152($sp); \ | |
54 | stq $16, 160($sp); \ | |
55 | stq $17, 168($sp); \ | |
56 | stq $18, 176($sp) | |
57 | ||
58 | #define RESTORE_ALL \ | |
59 | lda $19, alpha_mv; \ | |
60 | ldq $0, 0($sp); \ | |
61 | ldq $1, 8($sp); \ | |
62 | ldq $2, 16($sp); \ | |
63 | ldq $3, 24($sp); \ | |
64 | ldq $21, 152($sp); \ | |
65 | ldq $20, HAE_CACHE($19); \ | |
66 | ldq $4, 32($sp); \ | |
67 | ldq $5, 40($sp); \ | |
68 | ldq $6, 48($sp); \ | |
69 | ldq $7, 56($sp); \ | |
70 | subq $20, $21, $20; \ | |
71 | ldq $8, 64($sp); \ | |
72 | beq $20, 99f; \ | |
73 | ldq $20, HAE_REG($19); \ | |
74 | stq $21, HAE_CACHE($19); \ | |
75 | stq $21, 0($20); \ | |
1da177e4 LT |
76 | 99:; \ |
77 | ldq $19, 72($sp); \ | |
78 | ldq $20, 80($sp); \ | |
79 | ldq $21, 88($sp); \ | |
80 | ldq $22, 96($sp); \ | |
81 | ldq $23, 104($sp); \ | |
82 | ldq $24, 112($sp); \ | |
83 | ldq $25, 120($sp); \ | |
84 | ldq $26, 128($sp); \ | |
85 | ldq $27, 136($sp); \ | |
86 | ldq $28, 144($sp); \ | |
87 | addq $sp, SP_OFF, $sp | |
88 | ||
89 | /* | |
90 | * Non-syscall kernel entry points. | |
91 | */ | |
92 | ||
93 | .align 4 | |
94 | .globl entInt | |
95 | .ent entInt | |
96 | entInt: | |
97 | SAVE_ALL | |
98 | lda $8, 0x3fff | |
99 | lda $26, ret_from_sys_call | |
100 | bic $sp, $8, $8 | |
101 | mov $sp, $19 | |
102 | jsr $31, do_entInt | |
103 | .end entInt | |
104 | ||
105 | .align 4 | |
106 | .globl entArith | |
107 | .ent entArith | |
108 | entArith: | |
109 | SAVE_ALL | |
110 | lda $8, 0x3fff | |
111 | lda $26, ret_from_sys_call | |
112 | bic $sp, $8, $8 | |
113 | mov $sp, $18 | |
114 | jsr $31, do_entArith | |
115 | .end entArith | |
116 | ||
117 | .align 4 | |
118 | .globl entMM | |
119 | .ent entMM | |
120 | entMM: | |
121 | SAVE_ALL | |
122 | /* save $9 - $15 so the inline exception code can manipulate them. */ | |
123 | subq $sp, 56, $sp | |
124 | stq $9, 0($sp) | |
125 | stq $10, 8($sp) | |
126 | stq $11, 16($sp) | |
127 | stq $12, 24($sp) | |
128 | stq $13, 32($sp) | |
129 | stq $14, 40($sp) | |
130 | stq $15, 48($sp) | |
131 | addq $sp, 56, $19 | |
132 | /* handle the fault */ | |
133 | lda $8, 0x3fff | |
134 | bic $sp, $8, $8 | |
135 | jsr $26, do_page_fault | |
136 | /* reload the registers after the exception code played. */ | |
137 | ldq $9, 0($sp) | |
138 | ldq $10, 8($sp) | |
139 | ldq $11, 16($sp) | |
140 | ldq $12, 24($sp) | |
141 | ldq $13, 32($sp) | |
142 | ldq $14, 40($sp) | |
143 | ldq $15, 48($sp) | |
144 | addq $sp, 56, $sp | |
145 | /* finish up the syscall as normal. */ | |
146 | br ret_from_sys_call | |
147 | .end entMM | |
148 | ||
149 | .align 4 | |
150 | .globl entIF | |
151 | .ent entIF | |
152 | entIF: | |
153 | SAVE_ALL | |
154 | lda $8, 0x3fff | |
155 | lda $26, ret_from_sys_call | |
156 | bic $sp, $8, $8 | |
157 | mov $sp, $17 | |
158 | jsr $31, do_entIF | |
159 | .end entIF | |
160 | ||
161 | .align 4 | |
162 | .globl entUna | |
163 | .ent entUna | |
164 | entUna: | |
165 | lda $sp, -256($sp) | |
166 | stq $0, 0($sp) | |
167 | ldq $0, 256($sp) /* get PS */ | |
168 | stq $1, 8($sp) | |
169 | stq $2, 16($sp) | |
170 | stq $3, 24($sp) | |
171 | and $0, 8, $0 /* user mode? */ | |
172 | stq $4, 32($sp) | |
173 | bne $0, entUnaUser /* yup -> do user-level unaligned fault */ | |
174 | stq $5, 40($sp) | |
175 | stq $6, 48($sp) | |
176 | stq $7, 56($sp) | |
177 | stq $8, 64($sp) | |
178 | stq $9, 72($sp) | |
179 | stq $10, 80($sp) | |
180 | stq $11, 88($sp) | |
181 | stq $12, 96($sp) | |
182 | stq $13, 104($sp) | |
183 | stq $14, 112($sp) | |
184 | stq $15, 120($sp) | |
185 | /* 16-18 PAL-saved */ | |
186 | stq $19, 152($sp) | |
187 | stq $20, 160($sp) | |
188 | stq $21, 168($sp) | |
189 | stq $22, 176($sp) | |
190 | stq $23, 184($sp) | |
191 | stq $24, 192($sp) | |
192 | stq $25, 200($sp) | |
193 | stq $26, 208($sp) | |
194 | stq $27, 216($sp) | |
195 | stq $28, 224($sp) | |
d70ddac1 | 196 | mov $sp, $19 |
1da177e4 LT |
197 | stq $gp, 232($sp) |
198 | lda $8, 0x3fff | |
199 | stq $31, 248($sp) | |
200 | bic $sp, $8, $8 | |
201 | jsr $26, do_entUna | |
202 | ldq $0, 0($sp) | |
203 | ldq $1, 8($sp) | |
204 | ldq $2, 16($sp) | |
205 | ldq $3, 24($sp) | |
206 | ldq $4, 32($sp) | |
207 | ldq $5, 40($sp) | |
208 | ldq $6, 48($sp) | |
209 | ldq $7, 56($sp) | |
210 | ldq $8, 64($sp) | |
211 | ldq $9, 72($sp) | |
212 | ldq $10, 80($sp) | |
213 | ldq $11, 88($sp) | |
214 | ldq $12, 96($sp) | |
215 | ldq $13, 104($sp) | |
216 | ldq $14, 112($sp) | |
217 | ldq $15, 120($sp) | |
218 | /* 16-18 PAL-saved */ | |
219 | ldq $19, 152($sp) | |
220 | ldq $20, 160($sp) | |
221 | ldq $21, 168($sp) | |
222 | ldq $22, 176($sp) | |
223 | ldq $23, 184($sp) | |
224 | ldq $24, 192($sp) | |
225 | ldq $25, 200($sp) | |
226 | ldq $26, 208($sp) | |
227 | ldq $27, 216($sp) | |
228 | ldq $28, 224($sp) | |
229 | ldq $gp, 232($sp) | |
230 | lda $sp, 256($sp) | |
231 | call_pal PAL_rti | |
232 | .end entUna | |
233 | ||
234 | .align 4 | |
235 | .ent entUnaUser | |
236 | entUnaUser: | |
237 | ldq $0, 0($sp) /* restore original $0 */ | |
238 | lda $sp, 256($sp) /* pop entUna's stack frame */ | |
239 | SAVE_ALL /* setup normal kernel stack */ | |
240 | lda $sp, -56($sp) | |
241 | stq $9, 0($sp) | |
242 | stq $10, 8($sp) | |
243 | stq $11, 16($sp) | |
244 | stq $12, 24($sp) | |
245 | stq $13, 32($sp) | |
246 | stq $14, 40($sp) | |
247 | stq $15, 48($sp) | |
248 | lda $8, 0x3fff | |
249 | addq $sp, 56, $19 | |
250 | bic $sp, $8, $8 | |
251 | jsr $26, do_entUnaUser | |
252 | ldq $9, 0($sp) | |
253 | ldq $10, 8($sp) | |
254 | ldq $11, 16($sp) | |
255 | ldq $12, 24($sp) | |
256 | ldq $13, 32($sp) | |
257 | ldq $14, 40($sp) | |
258 | ldq $15, 48($sp) | |
259 | lda $sp, 56($sp) | |
260 | br ret_from_sys_call | |
261 | .end entUnaUser | |
262 | ||
263 | .align 4 | |
264 | .globl entDbg | |
265 | .ent entDbg | |
266 | entDbg: | |
267 | SAVE_ALL | |
268 | lda $8, 0x3fff | |
269 | lda $26, ret_from_sys_call | |
270 | bic $sp, $8, $8 | |
271 | mov $sp, $16 | |
272 | jsr $31, do_entDbg | |
273 | .end entDbg | |
274 | \f | |
275 | /* | |
276 | * The system call entry point is special. Most importantly, it looks | |
277 | * like a function call to userspace as far as clobbered registers. We | |
278 | * do preserve the argument registers (for syscall restarts) and $26 | |
279 | * (for leaf syscall functions). | |
280 | * | |
281 | * So much for theory. We don't take advantage of this yet. | |
282 | * | |
283 | * Note that a0-a2 are not saved by PALcode as with the other entry points. | |
284 | */ | |
285 | ||
286 | .align 4 | |
287 | .globl entSys | |
288 | .globl ret_from_sys_call | |
289 | .ent entSys | |
290 | entSys: | |
291 | SAVE_ALL | |
292 | lda $8, 0x3fff | |
293 | bic $sp, $8, $8 | |
294 | lda $4, NR_SYSCALLS($31) | |
295 | stq $16, SP_OFF+24($sp) | |
296 | lda $5, sys_call_table | |
297 | lda $27, sys_ni_syscall | |
298 | cmpult $0, $4, $4 | |
299 | ldl $3, TI_FLAGS($8) | |
300 | stq $17, SP_OFF+32($sp) | |
301 | s8addq $0, $5, $5 | |
302 | stq $18, SP_OFF+40($sp) | |
303 | blbs $3, strace | |
304 | beq $4, 1f | |
305 | ldq $27, 0($5) | |
306 | 1: jsr $26, ($27), alpha_ni_syscall | |
307 | ldgp $gp, 0($26) | |
308 | blt $0, $syscall_error /* the call failed */ | |
309 | stq $0, 0($sp) | |
310 | stq $31, 72($sp) /* a3=0 => no error */ | |
311 | ||
312 | .align 4 | |
313 | ret_from_sys_call: | |
314 | cmovne $26, 0, $19 /* $19 = 0 => non-restartable */ | |
315 | ldq $0, SP_OFF($sp) | |
316 | and $0, 8, $0 | |
77edffb6 | 317 | beq $0, ret_to_kernel |
494486a1 | 318 | ret_to_user: |
1da177e4 LT |
319 | /* Make sure need_resched and sigpending don't change between |
320 | sampling and the rti. */ | |
321 | lda $16, 7 | |
322 | call_pal PAL_swpipl | |
323 | ldl $5, TI_FLAGS($8) | |
324 | and $5, _TIF_WORK_MASK, $2 | |
494486a1 | 325 | bne $2, work_pending |
1da177e4 LT |
326 | restore_all: |
327 | RESTORE_ALL | |
328 | call_pal PAL_rti | |
329 | ||
77edffb6 AV |
330 | ret_to_kernel: |
331 | lda $16, 7 | |
332 | call_pal PAL_swpipl | |
333 | br restore_all | |
334 | ||
1da177e4 LT |
335 | .align 3 |
336 | $syscall_error: | |
337 | /* | |
338 | * Some system calls (e.g., ptrace) can return arbitrary | |
339 | * values which might normally be mistaken as error numbers. | |
340 | * Those functions must zero $0 (v0) directly in the stack | |
341 | * frame to indicate that a negative return value wasn't an | |
342 | * error number.. | |
343 | */ | |
344 | ldq $19, 0($sp) /* old syscall nr (zero if success) */ | |
345 | beq $19, $ret_success | |
346 | ||
347 | ldq $20, 72($sp) /* .. and this a3 */ | |
348 | subq $31, $0, $0 /* with error in v0 */ | |
349 | addq $31, 1, $1 /* set a3 for errno return */ | |
350 | stq $0, 0($sp) | |
351 | mov $31, $26 /* tell "ret_from_sys_call" we can restart */ | |
352 | stq $1, 72($sp) /* a3 for return */ | |
353 | br ret_from_sys_call | |
354 | ||
355 | $ret_success: | |
356 | stq $0, 0($sp) | |
357 | stq $31, 72($sp) /* a3=0 => no error */ | |
358 | br ret_from_sys_call | |
359 | .end entSys | |
360 | ||
361 | /* | |
362 | * Do all cleanup when returning from all interrupts and system calls. | |
363 | * | |
364 | * Arguments: | |
365 | * $5: TI_FLAGS. | |
366 | * $8: current. | |
367 | * $19: The old syscall number, or zero if this is not a return | |
368 | * from a syscall that errored and is possibly restartable. | |
494486a1 | 369 | * $20: The old a3 value |
1da177e4 LT |
370 | */ |
371 | ||
372 | .align 4 | |
373 | .ent work_pending | |
374 | work_pending: | |
375 | and $5, _TIF_NEED_RESCHED, $2 | |
376 | beq $2, $work_notifysig | |
377 | ||
378 | $work_resched: | |
379 | subq $sp, 16, $sp | |
380 | stq $19, 0($sp) /* save syscall nr */ | |
381 | stq $20, 8($sp) /* and error indication (a3) */ | |
382 | jsr $26, schedule | |
383 | ldq $19, 0($sp) | |
384 | ldq $20, 8($sp) | |
385 | addq $sp, 16, $sp | |
386 | /* Make sure need_resched and sigpending don't change between | |
387 | sampling and the rti. */ | |
388 | lda $16, 7 | |
389 | call_pal PAL_swpipl | |
390 | ldl $5, TI_FLAGS($8) | |
391 | and $5, _TIF_WORK_MASK, $2 | |
392 | beq $2, restore_all | |
393 | and $5, _TIF_NEED_RESCHED, $2 | |
394 | bne $2, $work_resched | |
395 | ||
396 | $work_notifysig: | |
b927b3e2 | 397 | mov $sp, $16 |
494486a1 | 398 | bsr $1, do_switch_stack |
b927b3e2 RH |
399 | mov $sp, $17 |
400 | mov $5, $18 | |
494486a1 AV |
401 | mov $19, $9 /* save old syscall number */ |
402 | mov $20, $10 /* save old a3 */ | |
403 | and $5, _TIF_SIGPENDING, $2 | |
404 | cmovne $2, 0, $9 /* we don't want double syscall restarts */ | |
1da177e4 | 405 | jsr $26, do_notify_resume |
494486a1 AV |
406 | mov $9, $19 |
407 | mov $10, $20 | |
1da177e4 | 408 | bsr $1, undo_switch_stack |
494486a1 | 409 | br ret_to_user |
1da177e4 LT |
410 | .end work_pending |
411 | ||
412 | /* | |
413 | * PTRACE syscall handler | |
414 | */ | |
415 | ||
416 | .align 4 | |
417 | .ent strace | |
418 | strace: | |
419 | /* set up signal stack, call syscall_trace */ | |
420 | bsr $1, do_switch_stack | |
421 | jsr $26, syscall_trace | |
422 | bsr $1, undo_switch_stack | |
423 | ||
424 | /* get the system call number and the arguments back.. */ | |
425 | ldq $0, 0($sp) | |
426 | ldq $16, SP_OFF+24($sp) | |
427 | ldq $17, SP_OFF+32($sp) | |
428 | ldq $18, SP_OFF+40($sp) | |
429 | ldq $19, 72($sp) | |
430 | ldq $20, 80($sp) | |
431 | ldq $21, 88($sp) | |
432 | ||
433 | /* get the system call pointer.. */ | |
434 | lda $1, NR_SYSCALLS($31) | |
435 | lda $2, sys_call_table | |
436 | lda $27, alpha_ni_syscall | |
437 | cmpult $0, $1, $1 | |
438 | s8addq $0, $2, $2 | |
439 | beq $1, 1f | |
440 | ldq $27, 0($2) | |
441 | 1: jsr $26, ($27), sys_gettimeofday | |
53293638 | 442 | ret_from_straced: |
1da177e4 LT |
443 | ldgp $gp, 0($26) |
444 | ||
445 | /* check return.. */ | |
446 | blt $0, $strace_error /* the call failed */ | |
447 | stq $31, 72($sp) /* a3=0 => no error */ | |
448 | $strace_success: | |
449 | stq $0, 0($sp) /* save return value */ | |
450 | ||
451 | bsr $1, do_switch_stack | |
452 | jsr $26, syscall_trace | |
453 | bsr $1, undo_switch_stack | |
454 | br $31, ret_from_sys_call | |
455 | ||
456 | .align 3 | |
457 | $strace_error: | |
458 | ldq $19, 0($sp) /* old syscall nr (zero if success) */ | |
459 | beq $19, $strace_success | |
460 | ldq $20, 72($sp) /* .. and this a3 */ | |
461 | ||
462 | subq $31, $0, $0 /* with error in v0 */ | |
463 | addq $31, 1, $1 /* set a3 for errno return */ | |
464 | stq $0, 0($sp) | |
465 | stq $1, 72($sp) /* a3 for return */ | |
466 | ||
467 | bsr $1, do_switch_stack | |
468 | mov $19, $9 /* save old syscall number */ | |
469 | mov $20, $10 /* save old a3 */ | |
470 | jsr $26, syscall_trace | |
471 | mov $9, $19 | |
472 | mov $10, $20 | |
473 | bsr $1, undo_switch_stack | |
474 | ||
475 | mov $31, $26 /* tell "ret_from_sys_call" we can restart */ | |
476 | br ret_from_sys_call | |
477 | .end strace | |
478 | \f | |
479 | /* | |
480 | * Save and restore the switch stack -- aka the balance of the user context. | |
481 | */ | |
482 | ||
483 | .align 4 | |
484 | .ent do_switch_stack | |
485 | do_switch_stack: | |
486 | lda $sp, -SWITCH_STACK_SIZE($sp) | |
487 | stq $9, 0($sp) | |
488 | stq $10, 8($sp) | |
489 | stq $11, 16($sp) | |
490 | stq $12, 24($sp) | |
491 | stq $13, 32($sp) | |
492 | stq $14, 40($sp) | |
493 | stq $15, 48($sp) | |
494 | stq $26, 56($sp) | |
495 | stt $f0, 64($sp) | |
496 | stt $f1, 72($sp) | |
497 | stt $f2, 80($sp) | |
498 | stt $f3, 88($sp) | |
499 | stt $f4, 96($sp) | |
500 | stt $f5, 104($sp) | |
501 | stt $f6, 112($sp) | |
502 | stt $f7, 120($sp) | |
503 | stt $f8, 128($sp) | |
504 | stt $f9, 136($sp) | |
505 | stt $f10, 144($sp) | |
506 | stt $f11, 152($sp) | |
507 | stt $f12, 160($sp) | |
508 | stt $f13, 168($sp) | |
509 | stt $f14, 176($sp) | |
510 | stt $f15, 184($sp) | |
511 | stt $f16, 192($sp) | |
512 | stt $f17, 200($sp) | |
513 | stt $f18, 208($sp) | |
514 | stt $f19, 216($sp) | |
515 | stt $f20, 224($sp) | |
516 | stt $f21, 232($sp) | |
517 | stt $f22, 240($sp) | |
518 | stt $f23, 248($sp) | |
519 | stt $f24, 256($sp) | |
520 | stt $f25, 264($sp) | |
521 | stt $f26, 272($sp) | |
522 | stt $f27, 280($sp) | |
523 | mf_fpcr $f0 # get fpcr | |
524 | stt $f28, 288($sp) | |
525 | stt $f29, 296($sp) | |
526 | stt $f30, 304($sp) | |
527 | stt $f0, 312($sp) # save fpcr in slot of $f31 | |
528 | ldt $f0, 64($sp) # dont let "do_switch_stack" change fp state. | |
529 | ret $31, ($1), 1 | |
530 | .end do_switch_stack | |
531 | ||
532 | .align 4 | |
533 | .ent undo_switch_stack | |
534 | undo_switch_stack: | |
535 | ldq $9, 0($sp) | |
536 | ldq $10, 8($sp) | |
537 | ldq $11, 16($sp) | |
538 | ldq $12, 24($sp) | |
539 | ldq $13, 32($sp) | |
540 | ldq $14, 40($sp) | |
541 | ldq $15, 48($sp) | |
542 | ldq $26, 56($sp) | |
543 | ldt $f30, 312($sp) # get saved fpcr | |
544 | ldt $f0, 64($sp) | |
545 | ldt $f1, 72($sp) | |
546 | ldt $f2, 80($sp) | |
547 | ldt $f3, 88($sp) | |
548 | mt_fpcr $f30 # install saved fpcr | |
549 | ldt $f4, 96($sp) | |
550 | ldt $f5, 104($sp) | |
551 | ldt $f6, 112($sp) | |
552 | ldt $f7, 120($sp) | |
553 | ldt $f8, 128($sp) | |
554 | ldt $f9, 136($sp) | |
555 | ldt $f10, 144($sp) | |
556 | ldt $f11, 152($sp) | |
557 | ldt $f12, 160($sp) | |
558 | ldt $f13, 168($sp) | |
559 | ldt $f14, 176($sp) | |
560 | ldt $f15, 184($sp) | |
561 | ldt $f16, 192($sp) | |
562 | ldt $f17, 200($sp) | |
563 | ldt $f18, 208($sp) | |
564 | ldt $f19, 216($sp) | |
565 | ldt $f20, 224($sp) | |
566 | ldt $f21, 232($sp) | |
567 | ldt $f22, 240($sp) | |
568 | ldt $f23, 248($sp) | |
569 | ldt $f24, 256($sp) | |
570 | ldt $f25, 264($sp) | |
571 | ldt $f26, 272($sp) | |
572 | ldt $f27, 280($sp) | |
573 | ldt $f28, 288($sp) | |
574 | ldt $f29, 296($sp) | |
575 | ldt $f30, 304($sp) | |
576 | lda $sp, SWITCH_STACK_SIZE($sp) | |
577 | ret $31, ($1), 1 | |
578 | .end undo_switch_stack | |
579 | \f | |
580 | /* | |
581 | * The meat of the context switch code. | |
582 | */ | |
583 | ||
584 | .align 4 | |
585 | .globl alpha_switch_to | |
586 | .ent alpha_switch_to | |
587 | alpha_switch_to: | |
588 | .prologue 0 | |
589 | bsr $1, do_switch_stack | |
590 | call_pal PAL_swpctx | |
591 | lda $8, 0x3fff | |
592 | bsr $1, undo_switch_stack | |
593 | bic $sp, $8, $8 | |
594 | mov $17, $0 | |
595 | ret | |
596 | .end alpha_switch_to | |
597 | ||
598 | /* | |
599 | * New processes begin life here. | |
600 | */ | |
601 | ||
602 | .globl ret_from_fork | |
603 | .align 4 | |
604 | .ent ret_from_fork | |
605 | ret_from_fork: | |
606 | lda $26, ret_from_sys_call | |
607 | mov $17, $16 | |
608 | jmp $31, schedule_tail | |
609 | .end ret_from_fork | |
610 | ||
611 | /* | |
612 | * kernel_thread(fn, arg, clone_flags) | |
613 | */ | |
614 | .align 4 | |
615 | .globl kernel_thread | |
616 | .ent kernel_thread | |
617 | kernel_thread: | |
618 | /* We can be called from a module. */ | |
619 | ldgp $gp, 0($27) | |
620 | .prologue 1 | |
621 | subq $sp, SP_OFF+6*8, $sp | |
622 | br $1, 2f /* load start address */ | |
623 | ||
624 | /* We've now "returned" from a fake system call. */ | |
625 | unop | |
626 | blt $0, 1f /* error? */ | |
627 | ldi $1, 0x3fff | |
628 | beq $20, 1f /* parent or child? */ | |
629 | ||
630 | bic $sp, $1, $8 /* in child. */ | |
631 | jsr $26, ($27) | |
632 | ldgp $gp, 0($26) | |
633 | mov $0, $16 | |
634 | mov $31, $26 | |
635 | jmp $31, sys_exit | |
636 | ||
637 | 1: ret /* in parent. */ | |
638 | ||
639 | .align 4 | |
640 | 2: /* Fake a system call stack frame, as we can't do system calls | |
641 | from kernel space. Note that we store FN and ARG as they | |
642 | need to be set up in the child for the call. Also store $8 | |
643 | and $26 for use in the parent. */ | |
644 | stq $31, SP_OFF($sp) /* ps */ | |
645 | stq $1, SP_OFF+8($sp) /* pc */ | |
646 | stq $gp, SP_OFF+16($sp) /* gp */ | |
647 | stq $16, 136($sp) /* $27; FN for child */ | |
648 | stq $17, SP_OFF+24($sp) /* $16; ARG for child */ | |
649 | stq $8, 64($sp) /* $8 */ | |
650 | stq $26, 128($sp) /* $26 */ | |
651 | /* Avoid the HAE being gratuitously wrong, to avoid restoring it. */ | |
652 | ldq $2, alpha_mv+HAE_CACHE | |
653 | stq $2, 152($sp) /* HAE */ | |
654 | ||
655 | /* Shuffle FLAGS to the front; add CLONE_VM. */ | |
656 | ldi $1, CLONE_VM|CLONE_UNTRACED | |
657 | or $18, $1, $16 | |
658 | bsr $26, sys_clone | |
659 | ||
660 | /* We don't actually care for a3 success widgetry in the kernel. | |
661 | Not for positive errno values. */ | |
662 | stq $0, 0($sp) /* $0 */ | |
77edffb6 | 663 | br ret_to_kernel |
1da177e4 LT |
664 | .end kernel_thread |
665 | ||
666 | /* | |
3db03b4a | 667 | * kernel_execve(path, argv, envp) |
1da177e4 LT |
668 | */ |
669 | .align 4 | |
3db03b4a AB |
670 | .globl kernel_execve |
671 | .ent kernel_execve | |
672 | kernel_execve: | |
1da177e4 LT |
673 | /* We can be called from a module. */ |
674 | ldgp $gp, 0($27) | |
675 | lda $sp, -(32+SIZEOF_PT_REGS+8)($sp) | |
676 | .frame $sp, 32+SIZEOF_PT_REGS+8, $26, 0 | |
677 | stq $26, 0($sp) | |
678 | stq $16, 8($sp) | |
679 | stq $17, 16($sp) | |
680 | stq $18, 24($sp) | |
681 | .prologue 1 | |
682 | ||
683 | lda $16, 32($sp) | |
684 | lda $17, 0 | |
685 | lda $18, SIZEOF_PT_REGS | |
686 | bsr $26, memset !samegp | |
687 | ||
688 | /* Avoid the HAE being gratuitously wrong, which would cause us | |
689 | to do the whole turn off interrupts thing and restore it. */ | |
690 | ldq $2, alpha_mv+HAE_CACHE | |
691 | stq $2, 152+32($sp) | |
692 | ||
693 | ldq $16, 8($sp) | |
694 | ldq $17, 16($sp) | |
695 | ldq $18, 24($sp) | |
696 | lda $19, 32($sp) | |
697 | bsr $26, do_execve !samegp | |
698 | ||
699 | ldq $26, 0($sp) | |
700 | bne $0, 1f /* error! */ | |
701 | ||
702 | /* Move the temporary pt_regs struct from its current location | |
703 | to the top of the kernel stack frame. See copy_thread for | |
704 | details for a normal process. */ | |
705 | lda $16, 0x4000 - SIZEOF_PT_REGS($8) | |
706 | lda $17, 32($sp) | |
707 | lda $18, SIZEOF_PT_REGS | |
708 | bsr $26, memmove !samegp | |
709 | ||
710 | /* Take that over as our new stack frame and visit userland! */ | |
711 | lda $sp, 0x4000 - SIZEOF_PT_REGS($8) | |
712 | br $31, ret_from_sys_call | |
713 | ||
714 | 1: lda $sp, 32+SIZEOF_PT_REGS+8($sp) | |
715 | ret | |
3db03b4a | 716 | .end kernel_execve |
1da177e4 LT |
717 | |
718 | \f | |
719 | /* | |
720 | * Special system calls. Most of these are special in that they either | |
721 | * have to play switch_stack games or in some way use the pt_regs struct. | |
722 | */ | |
723 | .align 4 | |
724 | .globl sys_fork | |
725 | .ent sys_fork | |
726 | sys_fork: | |
727 | .prologue 0 | |
728 | mov $sp, $21 | |
729 | bsr $1, do_switch_stack | |
730 | bis $31, SIGCHLD, $16 | |
731 | mov $31, $17 | |
732 | mov $31, $18 | |
733 | mov $31, $19 | |
734 | mov $31, $20 | |
735 | jsr $26, alpha_clone | |
736 | bsr $1, undo_switch_stack | |
737 | ret | |
738 | .end sys_fork | |
739 | ||
740 | .align 4 | |
741 | .globl sys_clone | |
742 | .ent sys_clone | |
743 | sys_clone: | |
744 | .prologue 0 | |
745 | mov $sp, $21 | |
746 | bsr $1, do_switch_stack | |
747 | /* $16, $17, $18, $19, $20 come from the user. */ | |
748 | jsr $26, alpha_clone | |
749 | bsr $1, undo_switch_stack | |
750 | ret | |
751 | .end sys_clone | |
752 | ||
753 | .align 4 | |
754 | .globl sys_vfork | |
755 | .ent sys_vfork | |
756 | sys_vfork: | |
757 | .prologue 0 | |
758 | mov $sp, $16 | |
759 | bsr $1, do_switch_stack | |
760 | jsr $26, alpha_vfork | |
761 | bsr $1, undo_switch_stack | |
762 | ret | |
763 | .end sys_vfork | |
764 | ||
765 | .align 4 | |
766 | .globl sys_sigreturn | |
767 | .ent sys_sigreturn | |
768 | sys_sigreturn: | |
769 | .prologue 0 | |
53293638 AV |
770 | lda $9, ret_from_straced |
771 | cmpult $26, $9, $9 | |
1da177e4 LT |
772 | mov $sp, $17 |
773 | lda $18, -SWITCH_STACK_SIZE($sp) | |
774 | lda $sp, -SWITCH_STACK_SIZE($sp) | |
775 | jsr $26, do_sigreturn | |
53293638 AV |
776 | bne $9, 1f |
777 | jsr $26, syscall_trace | |
778 | 1: br $1, undo_switch_stack | |
1da177e4 LT |
779 | br ret_from_sys_call |
780 | .end sys_sigreturn | |
781 | ||
782 | .align 4 | |
783 | .globl sys_rt_sigreturn | |
784 | .ent sys_rt_sigreturn | |
785 | sys_rt_sigreturn: | |
786 | .prologue 0 | |
53293638 AV |
787 | lda $9, ret_from_straced |
788 | cmpult $26, $9, $9 | |
1da177e4 LT |
789 | mov $sp, $17 |
790 | lda $18, -SWITCH_STACK_SIZE($sp) | |
791 | lda $sp, -SWITCH_STACK_SIZE($sp) | |
792 | jsr $26, do_rt_sigreturn | |
53293638 AV |
793 | bne $9, 1f |
794 | jsr $26, syscall_trace | |
795 | 1: br $1, undo_switch_stack | |
1da177e4 LT |
796 | br ret_from_sys_call |
797 | .end sys_rt_sigreturn | |
798 | ||
1da177e4 LT |
799 | .align 4 |
800 | .globl sys_sethae | |
801 | .ent sys_sethae | |
802 | sys_sethae: | |
803 | .prologue 0 | |
804 | stq $16, 152($sp) | |
805 | ret | |
806 | .end sys_sethae | |
807 | ||
808 | .align 4 | |
809 | .globl osf_getpriority | |
810 | .ent osf_getpriority | |
811 | osf_getpriority: | |
812 | lda $sp, -16($sp) | |
813 | stq $26, 0($sp) | |
814 | .prologue 0 | |
815 | ||
816 | jsr $26, sys_getpriority | |
817 | ||
818 | ldq $26, 0($sp) | |
819 | blt $0, 1f | |
820 | ||
821 | /* Return value is the unbiased priority, i.e. 20 - prio. | |
822 | This does result in negative return values, so signal | |
823 | no error by writing into the R0 slot. */ | |
824 | lda $1, 20 | |
825 | stq $31, 16($sp) | |
826 | subl $1, $0, $0 | |
827 | unop | |
828 | ||
829 | 1: lda $sp, 16($sp) | |
830 | ret | |
831 | .end osf_getpriority | |
832 | ||
833 | .align 4 | |
834 | .globl sys_getxuid | |
835 | .ent sys_getxuid | |
836 | sys_getxuid: | |
837 | .prologue 0 | |
838 | ldq $2, TI_TASK($8) | |
b6dff3ec DH |
839 | ldq $3, TASK_CRED($2) |
840 | ldl $0, CRED_UID($3) | |
841 | ldl $1, CRED_EUID($3) | |
1da177e4 LT |
842 | stq $1, 80($sp) |
843 | ret | |
844 | .end sys_getxuid | |
845 | ||
846 | .align 4 | |
847 | .globl sys_getxgid | |
848 | .ent sys_getxgid | |
849 | sys_getxgid: | |
850 | .prologue 0 | |
851 | ldq $2, TI_TASK($8) | |
b6dff3ec DH |
852 | ldq $3, TASK_CRED($2) |
853 | ldl $0, CRED_GID($3) | |
854 | ldl $1, CRED_EGID($3) | |
1da177e4 LT |
855 | stq $1, 80($sp) |
856 | ret | |
857 | .end sys_getxgid | |
858 | ||
859 | .align 4 | |
860 | .globl sys_getxpid | |
861 | .ent sys_getxpid | |
862 | sys_getxpid: | |
863 | .prologue 0 | |
864 | ldq $2, TI_TASK($8) | |
865 | ||
866 | /* See linux/kernel/timer.c sys_getppid for discussion | |
867 | about this loop. */ | |
9a5e7339 EB |
868 | ldq $3, TASK_GROUP_LEADER($2) |
869 | ldq $4, TASK_REAL_PARENT($3) | |
870 | ldl $0, TASK_TGID($2) | |
871 | 1: ldl $1, TASK_TGID($4) | |
1da177e4 | 872 | #ifdef CONFIG_SMP |
9a5e7339 | 873 | mov $4, $5 |
1da177e4 | 874 | mb |
9a5e7339 EB |
875 | ldq $3, TASK_GROUP_LEADER($2) |
876 | ldq $4, TASK_REAL_PARENT($3) | |
877 | cmpeq $4, $5, $5 | |
878 | beq $5, 1b | |
1da177e4 LT |
879 | #endif |
880 | stq $1, 80($sp) | |
1da177e4 LT |
881 | ret |
882 | .end sys_getxpid | |
883 | ||
884 | .align 4 | |
1134723e HC |
885 | .globl sys_alpha_pipe |
886 | .ent sys_alpha_pipe | |
887 | sys_alpha_pipe: | |
1da177e4 LT |
888 | lda $sp, -16($sp) |
889 | stq $26, 0($sp) | |
890 | .prologue 0 | |
891 | ||
10f303ae | 892 | mov $31, $17 |
1da177e4 | 893 | lda $16, 8($sp) |
10f303ae | 894 | jsr $26, do_pipe_flags |
1da177e4 LT |
895 | |
896 | ldq $26, 0($sp) | |
897 | bne $0, 1f | |
898 | ||
899 | /* The return values are in $0 and $20. */ | |
900 | ldl $1, 12($sp) | |
901 | ldl $0, 8($sp) | |
902 | ||
903 | stq $1, 80+16($sp) | |
904 | 1: lda $sp, 16($sp) | |
905 | ret | |
1134723e | 906 | .end sys_alpha_pipe |
1da177e4 | 907 | |
1da177e4 LT |
908 | .align 4 |
909 | .globl sys_execve | |
910 | .ent sys_execve | |
911 | sys_execve: | |
912 | .prologue 0 | |
913 | mov $sp, $19 | |
914 | jmp $31, do_sys_execve | |
915 | .end sys_execve | |
916 | ||
1da177e4 LT |
917 | .align 4 |
918 | .globl alpha_ni_syscall | |
919 | .ent alpha_ni_syscall | |
920 | alpha_ni_syscall: | |
921 | .prologue 0 | |
922 | /* Special because it also implements overflow handling via | |
923 | syscall number 0. And if you recall, zero is a special | |
924 | trigger for "not an error". Store large non-zero there. */ | |
925 | lda $0, -ENOSYS | |
926 | unop | |
927 | stq $0, 0($sp) | |
928 | ret | |
929 | .end alpha_ni_syscall |