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Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus
[deliverable/linux.git] / arch / sparc64 / kernel / process.c
1 /* arch/sparc64/kernel/process.c
2 *
3 * Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
5 * Copyright (C) 1997, 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
6 */
7
8 /*
9 * This file handles the architecture-dependent parts of process handling..
10 */
11
12 #include <stdarg.h>
13
14 #include <linux/errno.h>
15 #include <linux/module.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
18 #include <linux/kallsyms.h>
19 #include <linux/mm.h>
20 #include <linux/fs.h>
21 #include <linux/smp.h>
22 #include <linux/stddef.h>
23 #include <linux/ptrace.h>
24 #include <linux/slab.h>
25 #include <linux/user.h>
26 #include <linux/reboot.h>
27 #include <linux/delay.h>
28 #include <linux/compat.h>
29 #include <linux/tick.h>
30 #include <linux/init.h>
31 #include <linux/cpu.h>
32 #include <linux/elfcore.h>
33 #include <linux/sysrq.h>
34
35 #include <asm/oplib.h>
36 #include <asm/uaccess.h>
37 #include <asm/system.h>
38 #include <asm/page.h>
39 #include <asm/pgalloc.h>
40 #include <asm/pgtable.h>
41 #include <asm/processor.h>
42 #include <asm/pstate.h>
43 #include <asm/elf.h>
44 #include <asm/fpumacro.h>
45 #include <asm/head.h>
46 #include <asm/cpudata.h>
47 #include <asm/mmu_context.h>
48 #include <asm/unistd.h>
49 #include <asm/hypervisor.h>
50 #include <asm/sstate.h>
51 #include <asm/reboot.h>
52 #include <asm/syscalls.h>
53 #include <asm/irq_regs.h>
54 #include <asm/smp.h>
55
56 /* #define VERBOSE_SHOWREGS */
57
58 static void sparc64_yield(int cpu)
59 {
60 if (tlb_type != hypervisor)
61 return;
62
63 clear_thread_flag(TIF_POLLING_NRFLAG);
64 smp_mb__after_clear_bit();
65
66 while (!need_resched() && !cpu_is_offline(cpu)) {
67 unsigned long pstate;
68
69 /* Disable interrupts. */
70 __asm__ __volatile__(
71 "rdpr %%pstate, %0\n\t"
72 "andn %0, %1, %0\n\t"
73 "wrpr %0, %%g0, %%pstate"
74 : "=&r" (pstate)
75 : "i" (PSTATE_IE));
76
77 if (!need_resched() && !cpu_is_offline(cpu))
78 sun4v_cpu_yield();
79
80 /* Re-enable interrupts. */
81 __asm__ __volatile__(
82 "rdpr %%pstate, %0\n\t"
83 "or %0, %1, %0\n\t"
84 "wrpr %0, %%g0, %%pstate"
85 : "=&r" (pstate)
86 : "i" (PSTATE_IE));
87 }
88
89 set_thread_flag(TIF_POLLING_NRFLAG);
90 }
91
92 /* The idle loop on sparc64. */
93 void cpu_idle(void)
94 {
95 int cpu = smp_processor_id();
96
97 set_thread_flag(TIF_POLLING_NRFLAG);
98
99 while(1) {
100 tick_nohz_stop_sched_tick();
101
102 while (!need_resched() && !cpu_is_offline(cpu))
103 sparc64_yield(cpu);
104
105 tick_nohz_restart_sched_tick();
106
107 preempt_enable_no_resched();
108
109 #ifdef CONFIG_HOTPLUG_CPU
110 if (cpu_is_offline(cpu))
111 cpu_play_dead();
112 #endif
113
114 schedule();
115 preempt_disable();
116 }
117 }
118
119 void machine_halt(void)
120 {
121 sstate_halt();
122 prom_halt();
123 panic("Halt failed!");
124 }
125
126 void machine_alt_power_off(void)
127 {
128 sstate_poweroff();
129 prom_halt_power_off();
130 panic("Power-off failed!");
131 }
132
133 void machine_restart(char * cmd)
134 {
135 char *p;
136
137 sstate_reboot();
138 p = strchr (reboot_command, '\n');
139 if (p) *p = 0;
140 if (cmd)
141 prom_reboot(cmd);
142 if (*reboot_command)
143 prom_reboot(reboot_command);
144 prom_reboot("");
145 panic("Reboot failed!");
146 }
147
148 #ifdef CONFIG_COMPAT
149 static void show_regwindow32(struct pt_regs *regs)
150 {
151 struct reg_window32 __user *rw;
152 struct reg_window32 r_w;
153 mm_segment_t old_fs;
154
155 __asm__ __volatile__ ("flushw");
156 rw = compat_ptr((unsigned)regs->u_regs[14]);
157 old_fs = get_fs();
158 set_fs (USER_DS);
159 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
160 set_fs (old_fs);
161 return;
162 }
163
164 set_fs (old_fs);
165 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
166 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
167 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
168 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
169 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
170 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
171 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
172 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
173 }
174 #else
175 #define show_regwindow32(regs) do { } while (0)
176 #endif
177
178 static void show_regwindow(struct pt_regs *regs)
179 {
180 struct reg_window __user *rw;
181 struct reg_window *rwk;
182 struct reg_window r_w;
183 mm_segment_t old_fs;
184
185 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
186 __asm__ __volatile__ ("flushw");
187 rw = (struct reg_window __user *)
188 (regs->u_regs[14] + STACK_BIAS);
189 rwk = (struct reg_window *)
190 (regs->u_regs[14] + STACK_BIAS);
191 if (!(regs->tstate & TSTATE_PRIV)) {
192 old_fs = get_fs();
193 set_fs (USER_DS);
194 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
195 set_fs (old_fs);
196 return;
197 }
198 rwk = &r_w;
199 set_fs (old_fs);
200 }
201 } else {
202 show_regwindow32(regs);
203 return;
204 }
205 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
206 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
207 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
208 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
209 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
210 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
211 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
212 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
213 if (regs->tstate & TSTATE_PRIV)
214 print_symbol("I7: <%s>\n", rwk->ins[7]);
215 }
216
217 #ifdef CONFIG_SMP
218 static DEFINE_SPINLOCK(regdump_lock);
219 #endif
220
221 void __show_regs(struct pt_regs * regs)
222 {
223 #ifdef CONFIG_SMP
224 unsigned long flags;
225
226 /* Protect against xcall ipis which might lead to livelock on the lock */
227 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
228 "wrpr %0, %1, %%pstate"
229 : "=r" (flags)
230 : "i" (PSTATE_IE));
231 spin_lock(&regdump_lock);
232 #endif
233 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
234 regs->tpc, regs->tnpc, regs->y, print_tainted());
235 print_symbol("TPC: <%s>\n", regs->tpc);
236 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
237 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
238 regs->u_regs[3]);
239 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
240 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
241 regs->u_regs[7]);
242 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
243 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
244 regs->u_regs[11]);
245 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
246 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
247 regs->u_regs[15]);
248 print_symbol("RPC: <%s>\n", regs->u_regs[15]);
249 show_regwindow(regs);
250 #ifdef CONFIG_SMP
251 spin_unlock(&regdump_lock);
252 __asm__ __volatile__("wrpr %0, 0, %%pstate"
253 : : "r" (flags));
254 #endif
255 }
256
257 #ifdef VERBOSE_SHOWREGS
258 static void idump_from_user (unsigned int *pc)
259 {
260 int i;
261 int code;
262
263 if((((unsigned long) pc) & 3))
264 return;
265
266 pc -= 3;
267 for(i = -3; i < 6; i++) {
268 get_user(code, pc);
269 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
270 pc++;
271 }
272 printk("\n");
273 }
274 #endif
275
276 void show_regs(struct pt_regs *regs)
277 {
278 #ifdef VERBOSE_SHOWREGS
279 extern long etrap, etraptl1;
280 #endif
281 __show_regs(regs);
282 #if 0
283 #ifdef CONFIG_SMP
284 {
285 extern void smp_report_regs(void);
286
287 smp_report_regs();
288 }
289 #endif
290 #endif
291
292 #ifdef VERBOSE_SHOWREGS
293 if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
294 regs->u_regs[14] >= (long)current - PAGE_SIZE &&
295 regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
296 printk ("*********parent**********\n");
297 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
298 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
299 printk ("*********endpar**********\n");
300 }
301 #endif
302 }
303
304 #ifdef CONFIG_MAGIC_SYSRQ
305 struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
306 static DEFINE_SPINLOCK(global_reg_snapshot_lock);
307
308 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
309 int this_cpu)
310 {
311 flushw_all();
312
313 global_reg_snapshot[this_cpu].tstate = regs->tstate;
314 global_reg_snapshot[this_cpu].tpc = regs->tpc;
315 global_reg_snapshot[this_cpu].tnpc = regs->tnpc;
316 global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
317
318 if (regs->tstate & TSTATE_PRIV) {
319 struct reg_window *rw;
320
321 rw = (struct reg_window *)
322 (regs->u_regs[UREG_FP] + STACK_BIAS);
323 global_reg_snapshot[this_cpu].i7 = rw->ins[6];
324 } else
325 global_reg_snapshot[this_cpu].i7 = 0;
326
327 global_reg_snapshot[this_cpu].thread = tp;
328 }
329
330 /* In order to avoid hangs we do not try to synchronize with the
331 * global register dump client cpus. The last store they make is to
332 * the thread pointer, so do a short poll waiting for that to become
333 * non-NULL.
334 */
335 static void __global_reg_poll(struct global_reg_snapshot *gp)
336 {
337 int limit = 0;
338
339 while (!gp->thread && ++limit < 100) {
340 barrier();
341 udelay(1);
342 }
343 }
344
345 static void sysrq_handle_globreg(int key, struct tty_struct *tty)
346 {
347 struct thread_info *tp = current_thread_info();
348 struct pt_regs *regs = get_irq_regs();
349 #ifdef CONFIG_KALLSYMS
350 char buffer[KSYM_SYMBOL_LEN];
351 #endif
352 unsigned long flags;
353 int this_cpu, cpu;
354
355 if (!regs)
356 regs = tp->kregs;
357
358 spin_lock_irqsave(&global_reg_snapshot_lock, flags);
359
360 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
361
362 this_cpu = raw_smp_processor_id();
363
364 __global_reg_self(tp, regs, this_cpu);
365
366 smp_fetch_global_regs();
367
368 for_each_online_cpu(cpu) {
369 struct global_reg_snapshot *gp = &global_reg_snapshot[cpu];
370 struct thread_info *tp;
371
372 __global_reg_poll(gp);
373
374 tp = gp->thread;
375 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
376 (cpu == this_cpu ? '*' : ' '), cpu,
377 gp->tstate, gp->tpc, gp->tnpc,
378 ((tp && tp->task) ? tp->task->comm : "NULL"),
379 ((tp && tp->task) ? tp->task->pid : -1));
380 #ifdef CONFIG_KALLSYMS
381 if (gp->tstate & TSTATE_PRIV) {
382 sprint_symbol(buffer, gp->tpc);
383 printk(" TPC[%s] ", buffer);
384 sprint_symbol(buffer, gp->o7);
385 printk("O7[%s] ", buffer);
386 sprint_symbol(buffer, gp->i7);
387 printk("I7[%s]\n", buffer);
388 } else
389 #endif
390 {
391 printk(" TPC[%lx] O7[%lx] I7[%lx]\n",
392 gp->tpc, gp->o7, gp->i7);
393 }
394 }
395
396 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
397
398 spin_unlock_irqrestore(&global_reg_snapshot_lock, flags);
399 }
400
401 static struct sysrq_key_op sparc_globalreg_op = {
402 .handler = sysrq_handle_globreg,
403 .help_msg = "Globalregs",
404 .action_msg = "Show Global CPU Regs",
405 };
406
407 static int __init sparc_globreg_init(void)
408 {
409 return register_sysrq_key('y', &sparc_globalreg_op);
410 }
411
412 core_initcall(sparc_globreg_init);
413
414 #endif
415
416 unsigned long thread_saved_pc(struct task_struct *tsk)
417 {
418 struct thread_info *ti = task_thread_info(tsk);
419 unsigned long ret = 0xdeadbeefUL;
420
421 if (ti && ti->ksp) {
422 unsigned long *sp;
423 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
424 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
425 sp[14]) {
426 unsigned long *fp;
427 fp = (unsigned long *)(sp[14] + STACK_BIAS);
428 if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
429 ret = fp[15];
430 }
431 }
432 return ret;
433 }
434
435 /* Free current thread data structures etc.. */
436 void exit_thread(void)
437 {
438 struct thread_info *t = current_thread_info();
439
440 if (t->utraps) {
441 if (t->utraps[0] < 2)
442 kfree (t->utraps);
443 else
444 t->utraps[0]--;
445 }
446
447 if (test_and_clear_thread_flag(TIF_PERFCTR)) {
448 t->user_cntd0 = t->user_cntd1 = NULL;
449 t->pcr_reg = 0;
450 write_pcr(0);
451 }
452 }
453
454 void flush_thread(void)
455 {
456 struct thread_info *t = current_thread_info();
457 struct mm_struct *mm;
458
459 if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
460 clear_ti_thread_flag(t, TIF_ABI_PENDING);
461 if (test_ti_thread_flag(t, TIF_32BIT))
462 clear_ti_thread_flag(t, TIF_32BIT);
463 else
464 set_ti_thread_flag(t, TIF_32BIT);
465 }
466
467 mm = t->task->mm;
468 if (mm)
469 tsb_context_switch(mm);
470
471 set_thread_wsaved(0);
472
473 /* Turn off performance counters if on. */
474 if (test_and_clear_thread_flag(TIF_PERFCTR)) {
475 t->user_cntd0 = t->user_cntd1 = NULL;
476 t->pcr_reg = 0;
477 write_pcr(0);
478 }
479
480 /* Clear FPU register state. */
481 t->fpsaved[0] = 0;
482
483 if (get_thread_current_ds() != ASI_AIUS)
484 set_fs(USER_DS);
485 }
486
487 /* It's a bit more tricky when 64-bit tasks are involved... */
488 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
489 {
490 unsigned long fp, distance, rval;
491
492 if (!(test_thread_flag(TIF_32BIT))) {
493 csp += STACK_BIAS;
494 psp += STACK_BIAS;
495 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
496 fp += STACK_BIAS;
497 } else
498 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
499
500 /* Now 8-byte align the stack as this is mandatory in the
501 * Sparc ABI due to how register windows work. This hides
502 * the restriction from thread libraries etc. -DaveM
503 */
504 csp &= ~7UL;
505
506 distance = fp - psp;
507 rval = (csp - distance);
508 if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
509 rval = 0;
510 else if (test_thread_flag(TIF_32BIT)) {
511 if (put_user(((u32)csp),
512 &(((struct reg_window32 __user *)rval)->ins[6])))
513 rval = 0;
514 } else {
515 if (put_user(((u64)csp - STACK_BIAS),
516 &(((struct reg_window __user *)rval)->ins[6])))
517 rval = 0;
518 else
519 rval = rval - STACK_BIAS;
520 }
521
522 return rval;
523 }
524
525 /* Standard stuff. */
526 static inline void shift_window_buffer(int first_win, int last_win,
527 struct thread_info *t)
528 {
529 int i;
530
531 for (i = first_win; i < last_win; i++) {
532 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
533 memcpy(&t->reg_window[i], &t->reg_window[i+1],
534 sizeof(struct reg_window));
535 }
536 }
537
538 void synchronize_user_stack(void)
539 {
540 struct thread_info *t = current_thread_info();
541 unsigned long window;
542
543 flush_user_windows();
544 if ((window = get_thread_wsaved()) != 0) {
545 int winsize = sizeof(struct reg_window);
546 int bias = 0;
547
548 if (test_thread_flag(TIF_32BIT))
549 winsize = sizeof(struct reg_window32);
550 else
551 bias = STACK_BIAS;
552
553 window -= 1;
554 do {
555 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
556 struct reg_window *rwin = &t->reg_window[window];
557
558 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
559 shift_window_buffer(window, get_thread_wsaved() - 1, t);
560 set_thread_wsaved(get_thread_wsaved() - 1);
561 }
562 } while (window--);
563 }
564 }
565
566 static void stack_unaligned(unsigned long sp)
567 {
568 siginfo_t info;
569
570 info.si_signo = SIGBUS;
571 info.si_errno = 0;
572 info.si_code = BUS_ADRALN;
573 info.si_addr = (void __user *) sp;
574 info.si_trapno = 0;
575 force_sig_info(SIGBUS, &info, current);
576 }
577
578 void fault_in_user_windows(void)
579 {
580 struct thread_info *t = current_thread_info();
581 unsigned long window;
582 int winsize = sizeof(struct reg_window);
583 int bias = 0;
584
585 if (test_thread_flag(TIF_32BIT))
586 winsize = sizeof(struct reg_window32);
587 else
588 bias = STACK_BIAS;
589
590 flush_user_windows();
591 window = get_thread_wsaved();
592
593 if (likely(window != 0)) {
594 window -= 1;
595 do {
596 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
597 struct reg_window *rwin = &t->reg_window[window];
598
599 if (unlikely(sp & 0x7UL))
600 stack_unaligned(sp);
601
602 if (unlikely(copy_to_user((char __user *)sp,
603 rwin, winsize)))
604 goto barf;
605 } while (window--);
606 }
607 set_thread_wsaved(0);
608 return;
609
610 barf:
611 set_thread_wsaved(window + 1);
612 do_exit(SIGILL);
613 }
614
615 asmlinkage long sparc_do_fork(unsigned long clone_flags,
616 unsigned long stack_start,
617 struct pt_regs *regs,
618 unsigned long stack_size)
619 {
620 int __user *parent_tid_ptr, *child_tid_ptr;
621 unsigned long orig_i1 = regs->u_regs[UREG_I1];
622 long ret;
623
624 #ifdef CONFIG_COMPAT
625 if (test_thread_flag(TIF_32BIT)) {
626 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
627 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
628 } else
629 #endif
630 {
631 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
632 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
633 }
634
635 ret = do_fork(clone_flags, stack_start,
636 regs, stack_size,
637 parent_tid_ptr, child_tid_ptr);
638
639 /* If we get an error and potentially restart the system
640 * call, we're screwed because copy_thread() clobbered
641 * the parent's %o1. So detect that case and restore it
642 * here.
643 */
644 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
645 regs->u_regs[UREG_I1] = orig_i1;
646
647 return ret;
648 }
649
650 /* Copy a Sparc thread. The fork() return value conventions
651 * under SunOS are nothing short of bletcherous:
652 * Parent --> %o0 == childs pid, %o1 == 0
653 * Child --> %o0 == parents pid, %o1 == 1
654 */
655 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
656 unsigned long unused,
657 struct task_struct *p, struct pt_regs *regs)
658 {
659 struct thread_info *t = task_thread_info(p);
660 char *child_trap_frame;
661
662 /* Calculate offset to stack_frame & pt_regs */
663 child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
664 memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
665
666 t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
667 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
668 t->new_child = 1;
669 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
670 t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
671 t->fpsaved[0] = 0;
672
673 if (regs->tstate & TSTATE_PRIV) {
674 /* Special case, if we are spawning a kernel thread from
675 * a userspace task (via KMOD, NFS, or similar) we must
676 * disable performance counters in the child because the
677 * address space and protection realm are changing.
678 */
679 if (t->flags & _TIF_PERFCTR) {
680 t->user_cntd0 = t->user_cntd1 = NULL;
681 t->pcr_reg = 0;
682 t->flags &= ~_TIF_PERFCTR;
683 }
684 t->kregs->u_regs[UREG_FP] = t->ksp;
685 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
686 flush_register_windows();
687 memcpy((void *)(t->ksp + STACK_BIAS),
688 (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
689 sizeof(struct sparc_stackf));
690 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
691 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
692 } else {
693 if (t->flags & _TIF_32BIT) {
694 sp &= 0x00000000ffffffffUL;
695 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
696 }
697 t->kregs->u_regs[UREG_FP] = sp;
698 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
699 if (sp != regs->u_regs[UREG_FP]) {
700 unsigned long csp;
701
702 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
703 if (!csp)
704 return -EFAULT;
705 t->kregs->u_regs[UREG_FP] = csp;
706 }
707 if (t->utraps)
708 t->utraps[0]++;
709 }
710
711 /* Set the return value for the child. */
712 t->kregs->u_regs[UREG_I0] = current->pid;
713 t->kregs->u_regs[UREG_I1] = 1;
714
715 /* Set the second return value for the parent. */
716 regs->u_regs[UREG_I1] = 0;
717
718 if (clone_flags & CLONE_SETTLS)
719 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
720
721 return 0;
722 }
723
724 /*
725 * This is the mechanism for creating a new kernel thread.
726 *
727 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
728 * who haven't done an "execve()") should use this: it will work within
729 * a system call from a "real" process, but the process memory space will
730 * not be freed until both the parent and the child have exited.
731 */
732 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
733 {
734 long retval;
735
736 /* If the parent runs before fn(arg) is called by the child,
737 * the input registers of this function can be clobbered.
738 * So we stash 'fn' and 'arg' into global registers which
739 * will not be modified by the parent.
740 */
741 __asm__ __volatile__("mov %4, %%g2\n\t" /* Save FN into global */
742 "mov %5, %%g3\n\t" /* Save ARG into global */
743 "mov %1, %%g1\n\t" /* Clone syscall nr. */
744 "mov %2, %%o0\n\t" /* Clone flags. */
745 "mov 0, %%o1\n\t" /* usp arg == 0 */
746 "t 0x6d\n\t" /* Linux/Sparc clone(). */
747 "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
748 " mov %%o0, %0\n\t"
749 "jmpl %%g2, %%o7\n\t" /* Call the function. */
750 " mov %%g3, %%o0\n\t" /* Set arg in delay. */
751 "mov %3, %%g1\n\t"
752 "t 0x6d\n\t" /* Linux/Sparc exit(). */
753 /* Notreached by child. */
754 "1:" :
755 "=r" (retval) :
756 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
757 "i" (__NR_exit), "r" (fn), "r" (arg) :
758 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
759 return retval;
760 }
761
762 typedef struct {
763 union {
764 unsigned int pr_regs[32];
765 unsigned long pr_dregs[16];
766 } pr_fr;
767 unsigned int __unused;
768 unsigned int pr_fsr;
769 unsigned char pr_qcnt;
770 unsigned char pr_q_entrysize;
771 unsigned char pr_en;
772 unsigned int pr_q[64];
773 } elf_fpregset_t32;
774
775 /*
776 * fill in the fpu structure for a core dump.
777 */
778 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
779 {
780 unsigned long *kfpregs = current_thread_info()->fpregs;
781 unsigned long fprs = current_thread_info()->fpsaved[0];
782
783 if (test_thread_flag(TIF_32BIT)) {
784 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
785
786 if (fprs & FPRS_DL)
787 memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
788 sizeof(unsigned int) * 32);
789 else
790 memset(&fpregs32->pr_fr.pr_regs[0], 0,
791 sizeof(unsigned int) * 32);
792 fpregs32->pr_qcnt = 0;
793 fpregs32->pr_q_entrysize = 8;
794 memset(&fpregs32->pr_q[0], 0,
795 (sizeof(unsigned int) * 64));
796 if (fprs & FPRS_FEF) {
797 fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
798 fpregs32->pr_en = 1;
799 } else {
800 fpregs32->pr_fsr = 0;
801 fpregs32->pr_en = 0;
802 }
803 } else {
804 if(fprs & FPRS_DL)
805 memcpy(&fpregs->pr_regs[0], kfpregs,
806 sizeof(unsigned int) * 32);
807 else
808 memset(&fpregs->pr_regs[0], 0,
809 sizeof(unsigned int) * 32);
810 if(fprs & FPRS_DU)
811 memcpy(&fpregs->pr_regs[16], kfpregs+16,
812 sizeof(unsigned int) * 32);
813 else
814 memset(&fpregs->pr_regs[16], 0,
815 sizeof(unsigned int) * 32);
816 if(fprs & FPRS_FEF) {
817 fpregs->pr_fsr = current_thread_info()->xfsr[0];
818 fpregs->pr_gsr = current_thread_info()->gsr[0];
819 } else {
820 fpregs->pr_fsr = fpregs->pr_gsr = 0;
821 }
822 fpregs->pr_fprs = fprs;
823 }
824 return 1;
825 }
826
827 /*
828 * sparc_execve() executes a new program after the asm stub has set
829 * things up for us. This should basically do what I want it to.
830 */
831 asmlinkage int sparc_execve(struct pt_regs *regs)
832 {
833 int error, base = 0;
834 char *filename;
835
836 /* User register window flush is done by entry.S */
837
838 /* Check for indirect call. */
839 if (regs->u_regs[UREG_G1] == 0)
840 base = 1;
841
842 filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
843 error = PTR_ERR(filename);
844 if (IS_ERR(filename))
845 goto out;
846 error = do_execve(filename,
847 (char __user * __user *)
848 regs->u_regs[base + UREG_I1],
849 (char __user * __user *)
850 regs->u_regs[base + UREG_I2], regs);
851 putname(filename);
852 if (!error) {
853 fprs_write(0);
854 current_thread_info()->xfsr[0] = 0;
855 current_thread_info()->fpsaved[0] = 0;
856 regs->tstate &= ~TSTATE_PEF;
857 }
858 out:
859 return error;
860 }
861
862 unsigned long get_wchan(struct task_struct *task)
863 {
864 unsigned long pc, fp, bias = 0;
865 unsigned long thread_info_base;
866 struct reg_window *rw;
867 unsigned long ret = 0;
868 int count = 0;
869
870 if (!task || task == current ||
871 task->state == TASK_RUNNING)
872 goto out;
873
874 thread_info_base = (unsigned long) task_stack_page(task);
875 bias = STACK_BIAS;
876 fp = task_thread_info(task)->ksp + bias;
877
878 do {
879 /* Bogus frame pointer? */
880 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
881 fp >= (thread_info_base + THREAD_SIZE))
882 break;
883 rw = (struct reg_window *) fp;
884 pc = rw->ins[7];
885 if (!in_sched_functions(pc)) {
886 ret = pc;
887 goto out;
888 }
889 fp = rw->ins[6] + bias;
890 } while (++count < 16);
891
892 out:
893 return ret;
894 }
Linux kernel - Deliverables
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