059b0d0252245800bf415110644a659a9f6c5a8e
[linux-2.6.git] / arch / sparc64 / kernel / process.c
1 /*  $Id: process.c,v 1.131 2002/02/09 19:49:30 davem Exp $
2  *  arch/sparc64/kernel/process.c
3  *
4  *  Copyright (C) 1995, 1996 David S. Miller (davem@caip.rutgers.edu)
5  *  Copyright (C) 1996       Eddie C. Dost   (ecd@skynet.be)
6  *  Copyright (C) 1997, 1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
7  */
8
9 /*
10  * This file handles the architecture-dependent parts of process handling..
11  */
12
13 #include <stdarg.h>
14
15 #include <linux/config.h>
16 #include <linux/errno.h>
17 #include <linux/module.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/kallsyms.h>
21 #include <linux/mm.h>
22 #include <linux/smp.h>
23 #include <linux/smp_lock.h>
24 #include <linux/stddef.h>
25 #include <linux/ptrace.h>
26 #include <linux/slab.h>
27 #include <linux/user.h>
28 #include <linux/a.out.h>
29 #include <linux/config.h>
30 #include <linux/reboot.h>
31 #include <linux/delay.h>
32 #include <linux/compat.h>
33 #include <linux/init.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/unistd.h>
48
49 /* #define VERBOSE_SHOWREGS */
50
51 /*
52  * Nothing special yet...
53  */
54 void default_idle(void)
55 {
56 }
57
58 #ifndef CONFIG_SMP
59
60 /*
61  * the idle loop on a Sparc... ;)
62  */
63 void cpu_idle(void)
64 {
65         /* endless idle loop with no priority at all */
66         for (;;) {
67                 /* If current->work.need_resched is zero we should really
68                  * setup for a system wakup event and execute a shutdown
69                  * instruction.
70                  *
71                  * But this requires writing back the contents of the
72                  * L2 cache etc. so implement this later. -DaveM
73                  */
74                 while (!need_resched())
75                         barrier();
76
77                 preempt_enable_no_resched();
78                 schedule();
79                 preempt_disable();
80                 check_pgt_cache();
81         }
82 }
83
84 #else
85
86 /*
87  * the idle loop on a UltraMultiPenguin...
88  *
89  * TIF_POLLING_NRFLAG is set because we do not sleep the cpu
90  * inside of the idler task, so an interrupt is not needed
91  * to get a clean fast response.
92  *
93  * XXX Reverify this assumption... -DaveM
94  *
95  * Addendum: We do want it to do something for the signal
96  *           delivery case, we detect that by just seeing
97  *           if we are trying to send this to an idler or not.
98  */
99 void cpu_idle(void)
100 {
101         cpuinfo_sparc *cpuinfo = &local_cpu_data();
102         set_thread_flag(TIF_POLLING_NRFLAG);
103
104         while(1) {
105                 if (need_resched()) {
106                         cpuinfo->idle_volume = 0;
107                         preempt_enable_no_resched();
108                         schedule();
109                         preempt_disable();
110                         check_pgt_cache();
111                 }
112                 cpuinfo->idle_volume++;
113
114                 /* The store ordering is so that IRQ handlers on
115                  * other cpus see our increasing idleness for the buddy
116                  * redistribution algorithm.  -DaveM
117                  */
118                 membar_storeload_storestore();
119         }
120 }
121
122 #endif
123
124 extern char reboot_command [];
125
126 extern void (*prom_palette)(int);
127 extern void (*prom_keyboard)(void);
128
129 void machine_halt(void)
130 {
131         if (!serial_console && prom_palette)
132                 prom_palette (1);
133         if (prom_keyboard)
134                 prom_keyboard();
135         prom_halt();
136         panic("Halt failed!");
137 }
138
139 void machine_alt_power_off(void)
140 {
141         if (!serial_console && prom_palette)
142                 prom_palette(1);
143         if (prom_keyboard)
144                 prom_keyboard();
145         prom_halt_power_off();
146         panic("Power-off failed!");
147 }
148
149 void machine_restart(char * cmd)
150 {
151         char *p;
152         
153         p = strchr (reboot_command, '\n');
154         if (p) *p = 0;
155         if (!serial_console && prom_palette)
156                 prom_palette (1);
157         if (prom_keyboard)
158                 prom_keyboard();
159         if (cmd)
160                 prom_reboot(cmd);
161         if (*reboot_command)
162                 prom_reboot(reboot_command);
163         prom_reboot("");
164         panic("Reboot failed!");
165 }
166
167 #ifdef CONFIG_COMPAT
168 static void show_regwindow32(struct pt_regs *regs)
169 {
170         struct reg_window32 __user *rw;
171         struct reg_window32 r_w;
172         mm_segment_t old_fs;
173         
174         __asm__ __volatile__ ("flushw");
175         rw = compat_ptr((unsigned)regs->u_regs[14]);
176         old_fs = get_fs();
177         set_fs (USER_DS);
178         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
179                 set_fs (old_fs);
180                 return;
181         }
182
183         set_fs (old_fs);                        
184         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
185                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
186                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
187                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
188         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
189                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
190                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
191                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
192 }
193 #else
194 #define show_regwindow32(regs)  do { } while (0)
195 #endif
196
197 static void show_regwindow(struct pt_regs *regs)
198 {
199         struct reg_window __user *rw;
200         struct reg_window *rwk;
201         struct reg_window r_w;
202         mm_segment_t old_fs;
203
204         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
205                 __asm__ __volatile__ ("flushw");
206                 rw = (struct reg_window __user *)
207                         (regs->u_regs[14] + STACK_BIAS);
208                 rwk = (struct reg_window *)
209                         (regs->u_regs[14] + STACK_BIAS);
210                 if (!(regs->tstate & TSTATE_PRIV)) {
211                         old_fs = get_fs();
212                         set_fs (USER_DS);
213                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
214                                 set_fs (old_fs);
215                                 return;
216                         }
217                         rwk = &r_w;
218                         set_fs (old_fs);                        
219                 }
220         } else {
221                 show_regwindow32(regs);
222                 return;
223         }
224         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
225                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
226         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
227                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
228         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
229                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
230         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
231                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
232         if (regs->tstate & TSTATE_PRIV)
233                 print_symbol("I7: <%s>\n", rwk->ins[7]);
234 }
235
236 void show_stackframe(struct sparc_stackf *sf)
237 {
238         unsigned long size;
239         unsigned long *stk;
240         int i;
241
242         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
243                "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
244                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
245                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
246         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
247                "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
248                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
249                sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
250         printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
251                "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
252                (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
253                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
254                sf->xxargs[0]);
255         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
256         size -= STACKFRAME_SZ;
257         stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
258         i = 0;
259         do {
260                 printk("s%d: %016lx\n", i++, *stk++);
261         } while ((size -= sizeof(unsigned long)));
262 }
263
264 void show_stackframe32(struct sparc_stackf32 *sf)
265 {
266         unsigned long size;
267         unsigned *stk;
268         int i;
269
270         printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
271                sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
272         printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
273                sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
274         printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
275                sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
276         printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
277                sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
278         printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
279                "x3: %08x x4: %08x x5: %08x xx: %08x\n",
280                sf->structptr, sf->xargs[0], sf->xargs[1],
281                sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
282                sf->xxargs[0]);
283         size = ((unsigned long)sf->fp) - ((unsigned long)sf);
284         size -= STACKFRAME32_SZ;
285         stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
286         i = 0;
287         do {
288                 printk("s%d: %08x\n", i++, *stk++);
289         } while ((size -= sizeof(unsigned)));
290 }
291
292 #ifdef CONFIG_SMP
293 static DEFINE_SPINLOCK(regdump_lock);
294 #endif
295
296 void __show_regs(struct pt_regs * regs)
297 {
298 #ifdef CONFIG_SMP
299         unsigned long flags;
300
301         /* Protect against xcall ipis which might lead to livelock on the lock */
302         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
303                              "wrpr      %0, %1, %%pstate"
304                              : "=r" (flags)
305                              : "i" (PSTATE_IE));
306         spin_lock(&regdump_lock);
307 #endif
308         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
309                regs->tpc, regs->tnpc, regs->y, print_tainted());
310         print_symbol("TPC: <%s>\n", regs->tpc);
311         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
312                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
313                regs->u_regs[3]);
314         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
315                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
316                regs->u_regs[7]);
317         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
318                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
319                regs->u_regs[11]);
320         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
321                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
322                regs->u_regs[15]);
323         print_symbol("RPC: <%s>\n", regs->u_regs[15]);
324         show_regwindow(regs);
325 #ifdef CONFIG_SMP
326         spin_unlock(&regdump_lock);
327         __asm__ __volatile__("wrpr      %0, 0, %%pstate"
328                              : : "r" (flags));
329 #endif
330 }
331
332 #ifdef VERBOSE_SHOWREGS
333 static void idump_from_user (unsigned int *pc)
334 {
335         int i;
336         int code;
337         
338         if((((unsigned long) pc) & 3))
339                 return;
340         
341         pc -= 3;
342         for(i = -3; i < 6; i++) {
343                 get_user(code, pc);
344                 printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
345                 pc++;
346         }
347         printk("\n");
348 }
349 #endif
350
351 void show_regs(struct pt_regs *regs)
352 {
353 #ifdef VERBOSE_SHOWREGS
354         extern long etrap, etraptl1;
355 #endif
356         __show_regs(regs);
357 #ifdef CONFIG_SMP
358         {
359                 extern void smp_report_regs(void);
360
361                 smp_report_regs();
362         }
363 #endif
364
365 #ifdef VERBOSE_SHOWREGS 
366         if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
367             regs->u_regs[14] >= (long)current - PAGE_SIZE &&
368             regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
369                 printk ("*********parent**********\n");
370                 __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
371                 idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
372                 printk ("*********endpar**********\n");
373         }
374 #endif
375 }
376
377 void show_regs32(struct pt_regs32 *regs)
378 {
379         printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
380                regs->pc, regs->npc, regs->y, print_tainted());
381         printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
382                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
383                regs->u_regs[3]);
384         printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
385                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
386                regs->u_regs[7]);
387         printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
388                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
389                regs->u_regs[11]);
390         printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
391                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
392                regs->u_regs[15]);
393 }
394
395 unsigned long thread_saved_pc(struct task_struct *tsk)
396 {
397         struct thread_info *ti = task_thread_info(tsk);
398         unsigned long ret = 0xdeadbeefUL;
399         
400         if (ti && ti->ksp) {
401                 unsigned long *sp;
402                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
403                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
404                     sp[14]) {
405                         unsigned long *fp;
406                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
407                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
408                                 ret = fp[15];
409                 }
410         }
411         return ret;
412 }
413
414 /* Free current thread data structures etc.. */
415 void exit_thread(void)
416 {
417         struct thread_info *t = current_thread_info();
418
419         if (t->utraps) {
420                 if (t->utraps[0] < 2)
421                         kfree (t->utraps);
422                 else
423                         t->utraps[0]--;
424         }
425
426         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
427                 t->user_cntd0 = t->user_cntd1 = NULL;
428                 t->pcr_reg = 0;
429                 write_pcr(0);
430         }
431 }
432
433 void flush_thread(void)
434 {
435         struct thread_info *t = current_thread_info();
436
437         if (t->flags & _TIF_ABI_PENDING)
438                 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
439
440         if (t->task->mm) {
441                 unsigned long pgd_cache = 0UL;
442                 if (test_thread_flag(TIF_32BIT)) {
443                         struct mm_struct *mm = t->task->mm;
444                         pgd_t *pgd0 = &mm->pgd[0];
445                         pud_t *pud0 = pud_offset(pgd0, 0);
446
447                         if (pud_none(*pud0)) {
448                                 pmd_t *page = pmd_alloc_one(mm, 0);
449                                 pud_set(pud0, page);
450                         }
451                         pgd_cache = get_pgd_cache(pgd0);
452                 }
453                 __asm__ __volatile__("stxa %0, [%1] %2\n\t"
454                                      "membar #Sync"
455                                      : /* no outputs */
456                                      : "r" (pgd_cache),
457                                      "r" (TSB_REG),
458                                      "i" (ASI_DMMU));
459         }
460         set_thread_wsaved(0);
461
462         /* Turn off performance counters if on. */
463         if (test_and_clear_thread_flag(TIF_PERFCTR)) {
464                 t->user_cntd0 = t->user_cntd1 = NULL;
465                 t->pcr_reg = 0;
466                 write_pcr(0);
467         }
468
469         /* Clear FPU register state. */
470         t->fpsaved[0] = 0;
471         
472         if (get_thread_current_ds() != ASI_AIUS)
473                 set_fs(USER_DS);
474
475         /* Init new signal delivery disposition. */
476         clear_thread_flag(TIF_NEWSIGNALS);
477 }
478
479 /* It's a bit more tricky when 64-bit tasks are involved... */
480 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
481 {
482         unsigned long fp, distance, rval;
483
484         if (!(test_thread_flag(TIF_32BIT))) {
485                 csp += STACK_BIAS;
486                 psp += STACK_BIAS;
487                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
488                 fp += STACK_BIAS;
489         } else
490                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
491
492         /* Now 8-byte align the stack as this is mandatory in the
493          * Sparc ABI due to how register windows work.  This hides
494          * the restriction from thread libraries etc.  -DaveM
495          */
496         csp &= ~7UL;
497
498         distance = fp - psp;
499         rval = (csp - distance);
500         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
501                 rval = 0;
502         else if (test_thread_flag(TIF_32BIT)) {
503                 if (put_user(((u32)csp),
504                              &(((struct reg_window32 __user *)rval)->ins[6])))
505                         rval = 0;
506         } else {
507                 if (put_user(((u64)csp - STACK_BIAS),
508                              &(((struct reg_window __user *)rval)->ins[6])))
509                         rval = 0;
510                 else
511                         rval = rval - STACK_BIAS;
512         }
513
514         return rval;
515 }
516
517 /* Standard stuff. */
518 static inline void shift_window_buffer(int first_win, int last_win,
519                                        struct thread_info *t)
520 {
521         int i;
522
523         for (i = first_win; i < last_win; i++) {
524                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
525                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
526                        sizeof(struct reg_window));
527         }
528 }
529
530 void synchronize_user_stack(void)
531 {
532         struct thread_info *t = current_thread_info();
533         unsigned long window;
534
535         flush_user_windows();
536         if ((window = get_thread_wsaved()) != 0) {
537                 int winsize = sizeof(struct reg_window);
538                 int bias = 0;
539
540                 if (test_thread_flag(TIF_32BIT))
541                         winsize = sizeof(struct reg_window32);
542                 else
543                         bias = STACK_BIAS;
544
545                 window -= 1;
546                 do {
547                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
548                         struct reg_window *rwin = &t->reg_window[window];
549
550                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
551                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
552                                 set_thread_wsaved(get_thread_wsaved() - 1);
553                         }
554                 } while (window--);
555         }
556 }
557
558 void fault_in_user_windows(void)
559 {
560         struct thread_info *t = current_thread_info();
561         unsigned long window;
562         int winsize = sizeof(struct reg_window);
563         int bias = 0;
564
565         if (test_thread_flag(TIF_32BIT))
566                 winsize = sizeof(struct reg_window32);
567         else
568                 bias = STACK_BIAS;
569
570         flush_user_windows();
571         window = get_thread_wsaved();
572
573         if (window != 0) {
574                 window -= 1;
575                 do {
576                         unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
577                         struct reg_window *rwin = &t->reg_window[window];
578
579                         if (copy_to_user((char __user *)sp, rwin, winsize))
580                                 goto barf;
581                 } while (window--);
582         }
583         set_thread_wsaved(0);
584         return;
585
586 barf:
587         set_thread_wsaved(window + 1);
588         do_exit(SIGILL);
589 }
590
591 asmlinkage long sparc_do_fork(unsigned long clone_flags,
592                               unsigned long stack_start,
593                               struct pt_regs *regs,
594                               unsigned long stack_size)
595 {
596         int __user *parent_tid_ptr, *child_tid_ptr;
597
598 #ifdef CONFIG_COMPAT
599         if (test_thread_flag(TIF_32BIT)) {
600                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
601                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
602         } else
603 #endif
604         {
605                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
606                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
607         }
608
609         return do_fork(clone_flags, stack_start,
610                        regs, stack_size,
611                        parent_tid_ptr, child_tid_ptr);
612 }
613
614 /* Copy a Sparc thread.  The fork() return value conventions
615  * under SunOS are nothing short of bletcherous:
616  * Parent -->  %o0 == childs  pid, %o1 == 0
617  * Child  -->  %o0 == parents pid, %o1 == 1
618  */
619 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
620                 unsigned long unused,
621                 struct task_struct *p, struct pt_regs *regs)
622 {
623         struct thread_info *t = task_thread_info(p);
624         char *child_trap_frame;
625
626         /* Calculate offset to stack_frame & pt_regs */
627         child_trap_frame = task_stack_page(p) + (THREAD_SIZE - (TRACEREG_SZ+STACKFRAME_SZ));
628         memcpy(child_trap_frame, (((struct sparc_stackf *)regs)-1), (TRACEREG_SZ+STACKFRAME_SZ));
629
630         t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) | (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
631                 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
632         t->new_child = 1;
633         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
634         t->kregs = (struct pt_regs *)(child_trap_frame+sizeof(struct sparc_stackf));
635         t->fpsaved[0] = 0;
636
637         if (regs->tstate & TSTATE_PRIV) {
638                 /* Special case, if we are spawning a kernel thread from
639                  * a userspace task (via KMOD, NFS, or similar) we must
640                  * disable performance counters in the child because the
641                  * address space and protection realm are changing.
642                  */
643                 if (t->flags & _TIF_PERFCTR) {
644                         t->user_cntd0 = t->user_cntd1 = NULL;
645                         t->pcr_reg = 0;
646                         t->flags &= ~_TIF_PERFCTR;
647                 }
648                 t->kregs->u_regs[UREG_FP] = t->ksp;
649                 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
650                 flush_register_windows();
651                 memcpy((void *)(t->ksp + STACK_BIAS),
652                        (void *)(regs->u_regs[UREG_FP] + STACK_BIAS),
653                        sizeof(struct sparc_stackf));
654                 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
655                 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
656         } else {
657                 if (t->flags & _TIF_32BIT) {
658                         sp &= 0x00000000ffffffffUL;
659                         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
660                 }
661                 t->kregs->u_regs[UREG_FP] = sp;
662                 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
663                 if (sp != regs->u_regs[UREG_FP]) {
664                         unsigned long csp;
665
666                         csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
667                         if (!csp)
668                                 return -EFAULT;
669                         t->kregs->u_regs[UREG_FP] = csp;
670                 }
671                 if (t->utraps)
672                         t->utraps[0]++;
673         }
674
675         /* Set the return value for the child. */
676         t->kregs->u_regs[UREG_I0] = current->pid;
677         t->kregs->u_regs[UREG_I1] = 1;
678
679         /* Set the second return value for the parent. */
680         regs->u_regs[UREG_I1] = 0;
681
682         if (clone_flags & CLONE_SETTLS)
683                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
684
685         return 0;
686 }
687
688 /*
689  * This is the mechanism for creating a new kernel thread.
690  *
691  * NOTE! Only a kernel-only process(ie the swapper or direct descendants
692  * who haven't done an "execve()") should use this: it will work within
693  * a system call from a "real" process, but the process memory space will
694  * not be free'd until both the parent and the child have exited.
695  */
696 pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
697 {
698         long retval;
699
700         /* If the parent runs before fn(arg) is called by the child,
701          * the input registers of this function can be clobbered.
702          * So we stash 'fn' and 'arg' into global registers which
703          * will not be modified by the parent.
704          */
705         __asm__ __volatile__("mov %4, %%g2\n\t"    /* Save FN into global */
706                              "mov %5, %%g3\n\t"    /* Save ARG into global */
707                              "mov %1, %%g1\n\t"    /* Clone syscall nr. */
708                              "mov %2, %%o0\n\t"    /* Clone flags. */
709                              "mov 0, %%o1\n\t"     /* usp arg == 0 */
710                              "t 0x6d\n\t"          /* Linux/Sparc clone(). */
711                              "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
712                              " mov %%o0, %0\n\t"
713                              "jmpl %%g2, %%o7\n\t"   /* Call the function. */
714                              " mov %%g3, %%o0\n\t"   /* Set arg in delay. */
715                              "mov %3, %%g1\n\t"
716                              "t 0x6d\n\t"          /* Linux/Sparc exit(). */
717                              /* Notreached by child. */
718                              "1:" :
719                              "=r" (retval) :
720                              "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
721                              "i" (__NR_exit),  "r" (fn), "r" (arg) :
722                              "g1", "g2", "g3", "o0", "o1", "memory", "cc");
723         return retval;
724 }
725
726 /*
727  * fill in the user structure for a core dump..
728  */
729 void dump_thread(struct pt_regs * regs, struct user * dump)
730 {
731         /* Only should be used for SunOS and ancient a.out
732          * SparcLinux binaries...  Not worth implementing.
733          */
734         memset(dump, 0, sizeof(struct user));
735 }
736
737 typedef struct {
738         union {
739                 unsigned int    pr_regs[32];
740                 unsigned long   pr_dregs[16];
741         } pr_fr;
742         unsigned int __unused;
743         unsigned int    pr_fsr;
744         unsigned char   pr_qcnt;
745         unsigned char   pr_q_entrysize;
746         unsigned char   pr_en;
747         unsigned int    pr_q[64];
748 } elf_fpregset_t32;
749
750 /*
751  * fill in the fpu structure for a core dump.
752  */
753 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
754 {
755         unsigned long *kfpregs = current_thread_info()->fpregs;
756         unsigned long fprs = current_thread_info()->fpsaved[0];
757
758         if (test_thread_flag(TIF_32BIT)) {
759                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
760
761                 if (fprs & FPRS_DL)
762                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
763                                sizeof(unsigned int) * 32);
764                 else
765                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
766                                sizeof(unsigned int) * 32);
767                 fpregs32->pr_qcnt = 0;
768                 fpregs32->pr_q_entrysize = 8;
769                 memset(&fpregs32->pr_q[0], 0,
770                        (sizeof(unsigned int) * 64));
771                 if (fprs & FPRS_FEF) {
772                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
773                         fpregs32->pr_en = 1;
774                 } else {
775                         fpregs32->pr_fsr = 0;
776                         fpregs32->pr_en = 0;
777                 }
778         } else {
779                 if(fprs & FPRS_DL)
780                         memcpy(&fpregs->pr_regs[0], kfpregs,
781                                sizeof(unsigned int) * 32);
782                 else
783                         memset(&fpregs->pr_regs[0], 0,
784                                sizeof(unsigned int) * 32);
785                 if(fprs & FPRS_DU)
786                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
787                                sizeof(unsigned int) * 32);
788                 else
789                         memset(&fpregs->pr_regs[16], 0,
790                                sizeof(unsigned int) * 32);
791                 if(fprs & FPRS_FEF) {
792                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
793                         fpregs->pr_gsr = current_thread_info()->gsr[0];
794                 } else {
795                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
796                 }
797                 fpregs->pr_fprs = fprs;
798         }
799         return 1;
800 }
801
802 /*
803  * sparc_execve() executes a new program after the asm stub has set
804  * things up for us.  This should basically do what I want it to.
805  */
806 asmlinkage int sparc_execve(struct pt_regs *regs)
807 {
808         int error, base = 0;
809         char *filename;
810
811         /* User register window flush is done by entry.S */
812
813         /* Check for indirect call. */
814         if (regs->u_regs[UREG_G1] == 0)
815                 base = 1;
816
817         filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
818         error = PTR_ERR(filename);
819         if (IS_ERR(filename))
820                 goto out;
821         error = do_execve(filename,
822                           (char __user * __user *)
823                           regs->u_regs[base + UREG_I1],
824                           (char __user * __user *)
825                           regs->u_regs[base + UREG_I2], regs);
826         putname(filename);
827         if (!error) {
828                 fprs_write(0);
829                 current_thread_info()->xfsr[0] = 0;
830                 current_thread_info()->fpsaved[0] = 0;
831                 regs->tstate &= ~TSTATE_PEF;
832                 task_lock(current);
833                 current->ptrace &= ~PT_DTRACE;
834                 task_unlock(current);
835         }
836 out:
837         return error;
838 }
839
840 unsigned long get_wchan(struct task_struct *task)
841 {
842         unsigned long pc, fp, bias = 0;
843         unsigned long thread_info_base;
844         struct reg_window *rw;
845         unsigned long ret = 0;
846         int count = 0; 
847
848         if (!task || task == current ||
849             task->state == TASK_RUNNING)
850                 goto out;
851
852         thread_info_base = (unsigned long) task_stack_page(task);
853         bias = STACK_BIAS;
854         fp = task_thread_info(task)->ksp + bias;
855
856         do {
857                 /* Bogus frame pointer? */
858                 if (fp < (thread_info_base + sizeof(struct thread_info)) ||
859                     fp >= (thread_info_base + THREAD_SIZE))
860                         break;
861                 rw = (struct reg_window *) fp;
862                 pc = rw->ins[7];
863                 if (!in_sched_functions(pc)) {
864                         ret = pc;
865                         goto out;
866                 }
867                 fp = rw->ins[6] + bias;
868         } while (++count < 16);
869
870 out:
871         return ret;
872 }