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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/export.h>
16#include <linux/sched.h>
17#include <linux/kernel.h>
18#include <linux/mm.h>
19#include <linux/fs.h>
20#include <linux/smp.h>
21#include <linux/stddef.h>
22#include <linux/ptrace.h>
23#include <linux/slab.h>
24#include <linux/user.h>
25#include <linux/delay.h>
26#include <linux/compat.h>
27#include <linux/tick.h>
28#include <linux/init.h>
29#include <linux/cpu.h>
30#include <linux/elfcore.h>
31#include <linux/sysrq.h>
32#include <linux/nmi.h>
33
34#include <asm/uaccess.h>
35#include <asm/page.h>
36#include <asm/pgalloc.h>
37#include <asm/pgtable.h>
38#include <asm/processor.h>
39#include <asm/pstate.h>
40#include <asm/elf.h>
41#include <asm/fpumacro.h>
42#include <asm/head.h>
43#include <asm/cpudata.h>
44#include <asm/mmu_context.h>
45#include <asm/unistd.h>
46#include <asm/hypervisor.h>
47#include <asm/syscalls.h>
48#include <asm/irq_regs.h>
49#include <asm/smp.h>
50
51#include "kstack.h"
52
53static void sparc64_yield(int cpu)
54{
55 if (tlb_type != hypervisor) {
56 touch_nmi_watchdog();
57 return;
58 }
59
60 clear_thread_flag(TIF_POLLING_NRFLAG);
61 smp_mb__after_clear_bit();
62
63 while (!need_resched() && !cpu_is_offline(cpu)) {
64 unsigned long pstate;
65
66 /* Disable interrupts. */
67 __asm__ __volatile__(
68 "rdpr %%pstate, %0\n\t"
69 "andn %0, %1, %0\n\t"
70 "wrpr %0, %%g0, %%pstate"
71 : "=&r" (pstate)
72 : "i" (PSTATE_IE));
73
74 if (!need_resched() && !cpu_is_offline(cpu))
75 sun4v_cpu_yield();
76
77 /* Re-enable interrupts. */
78 __asm__ __volatile__(
79 "rdpr %%pstate, %0\n\t"
80 "or %0, %1, %0\n\t"
81 "wrpr %0, %%g0, %%pstate"
82 : "=&r" (pstate)
83 : "i" (PSTATE_IE));
84 }
85
86 set_thread_flag(TIF_POLLING_NRFLAG);
87}
88
89/* The idle loop on sparc64. */
90void cpu_idle(void)
91{
92 int cpu = smp_processor_id();
93
94 set_thread_flag(TIF_POLLING_NRFLAG);
95
96 while(1) {
97 tick_nohz_idle_enter();
98 rcu_idle_enter();
99
100 while (!need_resched() && !cpu_is_offline(cpu))
101 sparc64_yield(cpu);
102
103 rcu_idle_exit();
104 tick_nohz_idle_exit();
105
106#ifdef CONFIG_HOTPLUG_CPU
107 if (cpu_is_offline(cpu)) {
108 sched_preempt_enable_no_resched();
109 cpu_play_dead();
110 }
111#endif
112 schedule_preempt_disabled();
113 }
114}
115
116#ifdef CONFIG_COMPAT
117static void show_regwindow32(struct pt_regs *regs)
118{
119 struct reg_window32 __user *rw;
120 struct reg_window32 r_w;
121 mm_segment_t old_fs;
122
123 __asm__ __volatile__ ("flushw");
124 rw = compat_ptr((unsigned)regs->u_regs[14]);
125 old_fs = get_fs();
126 set_fs (USER_DS);
127 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
128 set_fs (old_fs);
129 return;
130 }
131
132 set_fs (old_fs);
133 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
134 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
135 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
136 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
137 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
138 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
139 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
140 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
141}
142#else
143#define show_regwindow32(regs) do { } while (0)
144#endif
145
146static void show_regwindow(struct pt_regs *regs)
147{
148 struct reg_window __user *rw;
149 struct reg_window *rwk;
150 struct reg_window r_w;
151 mm_segment_t old_fs;
152
153 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
154 __asm__ __volatile__ ("flushw");
155 rw = (struct reg_window __user *)
156 (regs->u_regs[14] + STACK_BIAS);
157 rwk = (struct reg_window *)
158 (regs->u_regs[14] + STACK_BIAS);
159 if (!(regs->tstate & TSTATE_PRIV)) {
160 old_fs = get_fs();
161 set_fs (USER_DS);
162 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
163 set_fs (old_fs);
164 return;
165 }
166 rwk = &r_w;
167 set_fs (old_fs);
168 }
169 } else {
170 show_regwindow32(regs);
171 return;
172 }
173 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
174 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
175 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
176 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
177 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
178 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
179 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
180 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
181 if (regs->tstate & TSTATE_PRIV)
182 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
183}
184
185void show_regs(struct pt_regs *regs)
186{
187 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
188 regs->tpc, regs->tnpc, regs->y, print_tainted());
189 printk("TPC: <%pS>\n", (void *) regs->tpc);
190 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
191 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
192 regs->u_regs[3]);
193 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
194 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
195 regs->u_regs[7]);
196 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
197 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
198 regs->u_regs[11]);
199 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
200 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
201 regs->u_regs[15]);
202 printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
203 show_regwindow(regs);
204 show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
205}
206
207struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
208static DEFINE_SPINLOCK(global_reg_snapshot_lock);
209
210static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
211 int this_cpu)
212{
213 flushw_all();
214
215 global_reg_snapshot[this_cpu].tstate = regs->tstate;
216 global_reg_snapshot[this_cpu].tpc = regs->tpc;
217 global_reg_snapshot[this_cpu].tnpc = regs->tnpc;
218 global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
219
220 if (regs->tstate & TSTATE_PRIV) {
221 struct reg_window *rw;
222
223 rw = (struct reg_window *)
224 (regs->u_regs[UREG_FP] + STACK_BIAS);
225 if (kstack_valid(tp, (unsigned long) rw)) {
226 global_reg_snapshot[this_cpu].i7 = rw->ins[7];
227 rw = (struct reg_window *)
228 (rw->ins[6] + STACK_BIAS);
229 if (kstack_valid(tp, (unsigned long) rw))
230 global_reg_snapshot[this_cpu].rpc = rw->ins[7];
231 }
232 } else {
233 global_reg_snapshot[this_cpu].i7 = 0;
234 global_reg_snapshot[this_cpu].rpc = 0;
235 }
236 global_reg_snapshot[this_cpu].thread = tp;
237}
238
239/* In order to avoid hangs we do not try to synchronize with the
240 * global register dump client cpus. The last store they make is to
241 * the thread pointer, so do a short poll waiting for that to become
242 * non-NULL.
243 */
244static void __global_reg_poll(struct global_reg_snapshot *gp)
245{
246 int limit = 0;
247
248 while (!gp->thread && ++limit < 100) {
249 barrier();
250 udelay(1);
251 }
252}
253
254void arch_trigger_all_cpu_backtrace(void)
255{
256 struct thread_info *tp = current_thread_info();
257 struct pt_regs *regs = get_irq_regs();
258 unsigned long flags;
259 int this_cpu, cpu;
260
261 if (!regs)
262 regs = tp->kregs;
263
264 spin_lock_irqsave(&global_reg_snapshot_lock, flags);
265
266 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
267
268 this_cpu = raw_smp_processor_id();
269
270 __global_reg_self(tp, regs, this_cpu);
271
272 smp_fetch_global_regs();
273
274 for_each_online_cpu(cpu) {
275 struct global_reg_snapshot *gp = &global_reg_snapshot[cpu];
276
277 __global_reg_poll(gp);
278
279 tp = gp->thread;
280 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
281 (cpu == this_cpu ? '*' : ' '), cpu,
282 gp->tstate, gp->tpc, gp->tnpc,
283 ((tp && tp->task) ? tp->task->comm : "NULL"),
284 ((tp && tp->task) ? tp->task->pid : -1));
285
286 if (gp->tstate & TSTATE_PRIV) {
287 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
288 (void *) gp->tpc,
289 (void *) gp->o7,
290 (void *) gp->i7,
291 (void *) gp->rpc);
292 } else {
293 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
294 gp->tpc, gp->o7, gp->i7, gp->rpc);
295 }
296 }
297
298 memset(global_reg_snapshot, 0, sizeof(global_reg_snapshot));
299
300 spin_unlock_irqrestore(&global_reg_snapshot_lock, flags);
301}
302
303#ifdef CONFIG_MAGIC_SYSRQ
304
305static void sysrq_handle_globreg(int key)
306{
307 arch_trigger_all_cpu_backtrace();
308}
309
310static struct sysrq_key_op sparc_globalreg_op = {
311 .handler = sysrq_handle_globreg,
312 .help_msg = "Globalregs",
313 .action_msg = "Show Global CPU Regs",
314};
315
316static int __init sparc_globreg_init(void)
317{
318 return register_sysrq_key('y', &sparc_globalreg_op);
319}
320
321core_initcall(sparc_globreg_init);
322
323#endif
324
325unsigned long thread_saved_pc(struct task_struct *tsk)
326{
327 struct thread_info *ti = task_thread_info(tsk);
328 unsigned long ret = 0xdeadbeefUL;
329
330 if (ti && ti->ksp) {
331 unsigned long *sp;
332 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
333 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
334 sp[14]) {
335 unsigned long *fp;
336 fp = (unsigned long *)(sp[14] + STACK_BIAS);
337 if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
338 ret = fp[15];
339 }
340 }
341 return ret;
342}
343
344/* Free current thread data structures etc.. */
345void exit_thread(void)
346{
347 struct thread_info *t = current_thread_info();
348
349 if (t->utraps) {
350 if (t->utraps[0] < 2)
351 kfree (t->utraps);
352 else
353 t->utraps[0]--;
354 }
355}
356
357void flush_thread(void)
358{
359 struct thread_info *t = current_thread_info();
360 struct mm_struct *mm;
361
362 mm = t->task->mm;
363 if (mm)
364 tsb_context_switch(mm);
365
366 set_thread_wsaved(0);
367
368 /* Clear FPU register state. */
369 t->fpsaved[0] = 0;
370}
371
372/* It's a bit more tricky when 64-bit tasks are involved... */
373static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
374{
375 unsigned long fp, distance, rval;
376
377 if (!(test_thread_flag(TIF_32BIT))) {
378 csp += STACK_BIAS;
379 psp += STACK_BIAS;
380 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
381 fp += STACK_BIAS;
382 } else
383 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
384
385 /* Now align the stack as this is mandatory in the Sparc ABI
386 * due to how register windows work. This hides the
387 * restriction from thread libraries etc.
388 */
389 csp &= ~15UL;
390
391 distance = fp - psp;
392 rval = (csp - distance);
393 if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
394 rval = 0;
395 else if (test_thread_flag(TIF_32BIT)) {
396 if (put_user(((u32)csp),
397 &(((struct reg_window32 __user *)rval)->ins[6])))
398 rval = 0;
399 } else {
400 if (put_user(((u64)csp - STACK_BIAS),
401 &(((struct reg_window __user *)rval)->ins[6])))
402 rval = 0;
403 else
404 rval = rval - STACK_BIAS;
405 }
406
407 return rval;
408}
409
410/* Standard stuff. */
411static inline void shift_window_buffer(int first_win, int last_win,
412 struct thread_info *t)
413{
414 int i;
415
416 for (i = first_win; i < last_win; i++) {
417 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
418 memcpy(&t->reg_window[i], &t->reg_window[i+1],
419 sizeof(struct reg_window));
420 }
421}
422
423void synchronize_user_stack(void)
424{
425 struct thread_info *t = current_thread_info();
426 unsigned long window;
427
428 flush_user_windows();
429 if ((window = get_thread_wsaved()) != 0) {
430 int winsize = sizeof(struct reg_window);
431 int bias = 0;
432
433 if (test_thread_flag(TIF_32BIT))
434 winsize = sizeof(struct reg_window32);
435 else
436 bias = STACK_BIAS;
437
438 window -= 1;
439 do {
440 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
441 struct reg_window *rwin = &t->reg_window[window];
442
443 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
444 shift_window_buffer(window, get_thread_wsaved() - 1, t);
445 set_thread_wsaved(get_thread_wsaved() - 1);
446 }
447 } while (window--);
448 }
449}
450
451static void stack_unaligned(unsigned long sp)
452{
453 siginfo_t info;
454
455 info.si_signo = SIGBUS;
456 info.si_errno = 0;
457 info.si_code = BUS_ADRALN;
458 info.si_addr = (void __user *) sp;
459 info.si_trapno = 0;
460 force_sig_info(SIGBUS, &info, current);
461}
462
463void fault_in_user_windows(void)
464{
465 struct thread_info *t = current_thread_info();
466 unsigned long window;
467 int winsize = sizeof(struct reg_window);
468 int bias = 0;
469
470 if (test_thread_flag(TIF_32BIT))
471 winsize = sizeof(struct reg_window32);
472 else
473 bias = STACK_BIAS;
474
475 flush_user_windows();
476 window = get_thread_wsaved();
477
478 if (likely(window != 0)) {
479 window -= 1;
480 do {
481 unsigned long sp = (t->rwbuf_stkptrs[window] + bias);
482 struct reg_window *rwin = &t->reg_window[window];
483
484 if (unlikely(sp & 0x7UL))
485 stack_unaligned(sp);
486
487 if (unlikely(copy_to_user((char __user *)sp,
488 rwin, winsize)))
489 goto barf;
490 } while (window--);
491 }
492 set_thread_wsaved(0);
493 return;
494
495barf:
496 set_thread_wsaved(window + 1);
497 do_exit(SIGILL);
498}
499
500asmlinkage long sparc_do_fork(unsigned long clone_flags,
501 unsigned long stack_start,
502 struct pt_regs *regs,
503 unsigned long stack_size)
504{
505 int __user *parent_tid_ptr, *child_tid_ptr;
506 unsigned long orig_i1 = regs->u_regs[UREG_I1];
507 long ret;
508
509#ifdef CONFIG_COMPAT
510 if (test_thread_flag(TIF_32BIT)) {
511 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
512 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
513 } else
514#endif
515 {
516 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
517 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
518 }
519
520 ret = do_fork(clone_flags, stack_start,
521 regs, stack_size,
522 parent_tid_ptr, child_tid_ptr);
523
524 /* If we get an error and potentially restart the system
525 * call, we're screwed because copy_thread() clobbered
526 * the parent's %o1. So detect that case and restore it
527 * here.
528 */
529 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
530 regs->u_regs[UREG_I1] = orig_i1;
531
532 return ret;
533}
534
535/* Copy a Sparc thread. The fork() return value conventions
536 * under SunOS are nothing short of bletcherous:
537 * Parent --> %o0 == childs pid, %o1 == 0
538 * Child --> %o0 == parents pid, %o1 == 1
539 */
540int copy_thread(unsigned long clone_flags, unsigned long sp,
541 unsigned long unused,
542 struct task_struct *p, struct pt_regs *regs)
543{
544 struct thread_info *t = task_thread_info(p);
545 struct sparc_stackf *parent_sf;
546 unsigned long child_stack_sz;
547 char *child_trap_frame;
548 int kernel_thread;
549
550 kernel_thread = (regs->tstate & TSTATE_PRIV) ? 1 : 0;
551 parent_sf = ((struct sparc_stackf *) regs) - 1;
552
553 /* Calculate offset to stack_frame & pt_regs */
554 child_stack_sz = ((STACKFRAME_SZ + TRACEREG_SZ) +
555 (kernel_thread ? STACKFRAME_SZ : 0));
556 child_trap_frame = (task_stack_page(p) +
557 (THREAD_SIZE - child_stack_sz));
558 memcpy(child_trap_frame, parent_sf, child_stack_sz);
559
560 t->flags = (t->flags & ~((0xffUL << TI_FLAG_CWP_SHIFT) |
561 (0xffUL << TI_FLAG_CURRENT_DS_SHIFT))) |
562 (((regs->tstate + 1) & TSTATE_CWP) << TI_FLAG_CWP_SHIFT);
563 t->new_child = 1;
564 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
565 t->kregs = (struct pt_regs *) (child_trap_frame +
566 sizeof(struct sparc_stackf));
567 t->fpsaved[0] = 0;
568
569 if (kernel_thread) {
570 struct sparc_stackf *child_sf = (struct sparc_stackf *)
571 (child_trap_frame + (STACKFRAME_SZ + TRACEREG_SZ));
572
573 /* Zero terminate the stack backtrace. */
574 child_sf->fp = NULL;
575 t->kregs->u_regs[UREG_FP] =
576 ((unsigned long) child_sf) - STACK_BIAS;
577
578 t->flags |= ((long)ASI_P << TI_FLAG_CURRENT_DS_SHIFT);
579 t->kregs->u_regs[UREG_G6] = (unsigned long) t;
580 t->kregs->u_regs[UREG_G4] = (unsigned long) t->task;
581 } else {
582 if (t->flags & _TIF_32BIT) {
583 sp &= 0x00000000ffffffffUL;
584 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
585 }
586 t->kregs->u_regs[UREG_FP] = sp;
587 t->flags |= ((long)ASI_AIUS << TI_FLAG_CURRENT_DS_SHIFT);
588 if (sp != regs->u_regs[UREG_FP]) {
589 unsigned long csp;
590
591 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
592 if (!csp)
593 return -EFAULT;
594 t->kregs->u_regs[UREG_FP] = csp;
595 }
596 if (t->utraps)
597 t->utraps[0]++;
598 }
599
600 /* Set the return value for the child. */
601 t->kregs->u_regs[UREG_I0] = current->pid;
602 t->kregs->u_regs[UREG_I1] = 1;
603
604 /* Set the second return value for the parent. */
605 regs->u_regs[UREG_I1] = 0;
606
607 if (clone_flags & CLONE_SETTLS)
608 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
609
610 return 0;
611}
612
613/*
614 * This is the mechanism for creating a new kernel thread.
615 *
616 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
617 * who haven't done an "execve()") should use this: it will work within
618 * a system call from a "real" process, but the process memory space will
619 * not be freed until both the parent and the child have exited.
620 */
621pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
622{
623 long retval;
624
625 /* If the parent runs before fn(arg) is called by the child,
626 * the input registers of this function can be clobbered.
627 * So we stash 'fn' and 'arg' into global registers which
628 * will not be modified by the parent.
629 */
630 __asm__ __volatile__("mov %4, %%g2\n\t" /* Save FN into global */
631 "mov %5, %%g3\n\t" /* Save ARG into global */
632 "mov %1, %%g1\n\t" /* Clone syscall nr. */
633 "mov %2, %%o0\n\t" /* Clone flags. */
634 "mov 0, %%o1\n\t" /* usp arg == 0 */
635 "t 0x6d\n\t" /* Linux/Sparc clone(). */
636 "brz,a,pn %%o1, 1f\n\t" /* Parent, just return. */
637 " mov %%o0, %0\n\t"
638 "jmpl %%g2, %%o7\n\t" /* Call the function. */
639 " mov %%g3, %%o0\n\t" /* Set arg in delay. */
640 "mov %3, %%g1\n\t"
641 "t 0x6d\n\t" /* Linux/Sparc exit(). */
642 /* Notreached by child. */
643 "1:" :
644 "=r" (retval) :
645 "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
646 "i" (__NR_exit), "r" (fn), "r" (arg) :
647 "g1", "g2", "g3", "o0", "o1", "memory", "cc");
648 return retval;
649}
650EXPORT_SYMBOL(kernel_thread);
651
652typedef struct {
653 union {
654 unsigned int pr_regs[32];
655 unsigned long pr_dregs[16];
656 } pr_fr;
657 unsigned int __unused;
658 unsigned int pr_fsr;
659 unsigned char pr_qcnt;
660 unsigned char pr_q_entrysize;
661 unsigned char pr_en;
662 unsigned int pr_q[64];
663} elf_fpregset_t32;
664
665/*
666 * fill in the fpu structure for a core dump.
667 */
668int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
669{
670 unsigned long *kfpregs = current_thread_info()->fpregs;
671 unsigned long fprs = current_thread_info()->fpsaved[0];
672
673 if (test_thread_flag(TIF_32BIT)) {
674 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
675
676 if (fprs & FPRS_DL)
677 memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
678 sizeof(unsigned int) * 32);
679 else
680 memset(&fpregs32->pr_fr.pr_regs[0], 0,
681 sizeof(unsigned int) * 32);
682 fpregs32->pr_qcnt = 0;
683 fpregs32->pr_q_entrysize = 8;
684 memset(&fpregs32->pr_q[0], 0,
685 (sizeof(unsigned int) * 64));
686 if (fprs & FPRS_FEF) {
687 fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
688 fpregs32->pr_en = 1;
689 } else {
690 fpregs32->pr_fsr = 0;
691 fpregs32->pr_en = 0;
692 }
693 } else {
694 if(fprs & FPRS_DL)
695 memcpy(&fpregs->pr_regs[0], kfpregs,
696 sizeof(unsigned int) * 32);
697 else
698 memset(&fpregs->pr_regs[0], 0,
699 sizeof(unsigned int) * 32);
700 if(fprs & FPRS_DU)
701 memcpy(&fpregs->pr_regs[16], kfpregs+16,
702 sizeof(unsigned int) * 32);
703 else
704 memset(&fpregs->pr_regs[16], 0,
705 sizeof(unsigned int) * 32);
706 if(fprs & FPRS_FEF) {
707 fpregs->pr_fsr = current_thread_info()->xfsr[0];
708 fpregs->pr_gsr = current_thread_info()->gsr[0];
709 } else {
710 fpregs->pr_fsr = fpregs->pr_gsr = 0;
711 }
712 fpregs->pr_fprs = fprs;
713 }
714 return 1;
715}
716EXPORT_SYMBOL(dump_fpu);
717
718/*
719 * sparc_execve() executes a new program after the asm stub has set
720 * things up for us. This should basically do what I want it to.
721 */
722asmlinkage int sparc_execve(struct pt_regs *regs)
723{
724 int error, base = 0;
725 char *filename;
726
727 /* User register window flush is done by entry.S */
728
729 /* Check for indirect call. */
730 if (regs->u_regs[UREG_G1] == 0)
731 base = 1;
732
733 filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
734 error = PTR_ERR(filename);
735 if (IS_ERR(filename))
736 goto out;
737 error = do_execve(filename,
738 (const char __user *const __user *)
739 regs->u_regs[base + UREG_I1],
740 (const char __user *const __user *)
741 regs->u_regs[base + UREG_I2], regs);
742 putname(filename);
743 if (!error) {
744 fprs_write(0);
745 current_thread_info()->xfsr[0] = 0;
746 current_thread_info()->fpsaved[0] = 0;
747 regs->tstate &= ~TSTATE_PEF;
748 }
749out:
750 return error;
751}
752
753unsigned long get_wchan(struct task_struct *task)
754{
755 unsigned long pc, fp, bias = 0;
756 struct thread_info *tp;
757 struct reg_window *rw;
758 unsigned long ret = 0;
759 int count = 0;
760
761 if (!task || task == current ||
762 task->state == TASK_RUNNING)
763 goto out;
764
765 tp = task_thread_info(task);
766 bias = STACK_BIAS;
767 fp = task_thread_info(task)->ksp + bias;
768
769 do {
770 if (!kstack_valid(tp, fp))
771 break;
772 rw = (struct reg_window *) fp;
773 pc = rw->ins[7];
774 if (!in_sched_functions(pc)) {
775 ret = pc;
776 goto out;
777 }
778 fp = rw->ins[6] + bias;
779 } while (++count < 16);
780
781out:
782 return ret;
783}
1// SPDX-License-Identifier: GPL-2.0
2/* arch/sparc64/kernel/process.c
3 *
4 * Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
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/errno.h>
16#include <linux/export.h>
17#include <linux/sched.h>
18#include <linux/sched/debug.h>
19#include <linux/sched/task.h>
20#include <linux/sched/task_stack.h>
21#include <linux/kernel.h>
22#include <linux/mm.h>
23#include <linux/fs.h>
24#include <linux/smp.h>
25#include <linux/stddef.h>
26#include <linux/ptrace.h>
27#include <linux/slab.h>
28#include <linux/user.h>
29#include <linux/delay.h>
30#include <linux/compat.h>
31#include <linux/tick.h>
32#include <linux/init.h>
33#include <linux/cpu.h>
34#include <linux/perf_event.h>
35#include <linux/elfcore.h>
36#include <linux/sysrq.h>
37#include <linux/nmi.h>
38#include <linux/context_tracking.h>
39#include <linux/signal.h>
40
41#include <linux/uaccess.h>
42#include <asm/page.h>
43#include <asm/pgalloc.h>
44#include <asm/processor.h>
45#include <asm/pstate.h>
46#include <asm/elf.h>
47#include <asm/fpumacro.h>
48#include <asm/head.h>
49#include <asm/cpudata.h>
50#include <asm/mmu_context.h>
51#include <asm/unistd.h>
52#include <asm/hypervisor.h>
53#include <asm/syscalls.h>
54#include <asm/irq_regs.h>
55#include <asm/smp.h>
56#include <asm/pcr.h>
57
58#include "kstack.h"
59
60/* Idle loop support on sparc64. */
61void arch_cpu_idle(void)
62{
63 if (tlb_type != hypervisor) {
64 touch_nmi_watchdog();
65 local_irq_enable();
66 } else {
67 unsigned long pstate;
68
69 local_irq_enable();
70
71 /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
72 * the cpu sleep hypervisor call.
73 */
74 __asm__ __volatile__(
75 "rdpr %%pstate, %0\n\t"
76 "andn %0, %1, %0\n\t"
77 "wrpr %0, %%g0, %%pstate"
78 : "=&r" (pstate)
79 : "i" (PSTATE_IE));
80
81 if (!need_resched() && !cpu_is_offline(smp_processor_id())) {
82 sun4v_cpu_yield();
83 /* If resumed by cpu_poke then we need to explicitly
84 * call scheduler_ipi().
85 */
86 scheduler_poke();
87 }
88
89 /* Re-enable interrupts. */
90 __asm__ __volatile__(
91 "rdpr %%pstate, %0\n\t"
92 "or %0, %1, %0\n\t"
93 "wrpr %0, %%g0, %%pstate"
94 : "=&r" (pstate)
95 : "i" (PSTATE_IE));
96 }
97}
98
99#ifdef CONFIG_HOTPLUG_CPU
100void arch_cpu_idle_dead(void)
101{
102 sched_preempt_enable_no_resched();
103 cpu_play_dead();
104}
105#endif
106
107#ifdef CONFIG_COMPAT
108static void show_regwindow32(struct pt_regs *regs)
109{
110 struct reg_window32 __user *rw;
111 struct reg_window32 r_w;
112 mm_segment_t old_fs;
113
114 __asm__ __volatile__ ("flushw");
115 rw = compat_ptr((unsigned int)regs->u_regs[14]);
116 old_fs = get_fs();
117 set_fs (USER_DS);
118 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
119 set_fs (old_fs);
120 return;
121 }
122
123 set_fs (old_fs);
124 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
125 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
126 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
127 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
128 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
129 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
130 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
131 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
132}
133#else
134#define show_regwindow32(regs) do { } while (0)
135#endif
136
137static void show_regwindow(struct pt_regs *regs)
138{
139 struct reg_window __user *rw;
140 struct reg_window *rwk;
141 struct reg_window r_w;
142 mm_segment_t old_fs;
143
144 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
145 __asm__ __volatile__ ("flushw");
146 rw = (struct reg_window __user *)
147 (regs->u_regs[14] + STACK_BIAS);
148 rwk = (struct reg_window *)
149 (regs->u_regs[14] + STACK_BIAS);
150 if (!(regs->tstate & TSTATE_PRIV)) {
151 old_fs = get_fs();
152 set_fs (USER_DS);
153 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
154 set_fs (old_fs);
155 return;
156 }
157 rwk = &r_w;
158 set_fs (old_fs);
159 }
160 } else {
161 show_regwindow32(regs);
162 return;
163 }
164 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
165 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
166 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
167 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
168 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
169 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
170 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
171 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
172 if (regs->tstate & TSTATE_PRIV)
173 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
174}
175
176void show_regs(struct pt_regs *regs)
177{
178 show_regs_print_info(KERN_DEFAULT);
179
180 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
181 regs->tpc, regs->tnpc, regs->y, print_tainted());
182 printk("TPC: <%pS>\n", (void *) regs->tpc);
183 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
184 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
185 regs->u_regs[3]);
186 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
187 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
188 regs->u_regs[7]);
189 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
190 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
191 regs->u_regs[11]);
192 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
193 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
194 regs->u_regs[15]);
195 printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
196 show_regwindow(regs);
197 show_stack(current, (unsigned long *)regs->u_regs[UREG_FP], KERN_DEFAULT);
198}
199
200union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
201static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
202
203static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
204 int this_cpu)
205{
206 struct global_reg_snapshot *rp;
207
208 flushw_all();
209
210 rp = &global_cpu_snapshot[this_cpu].reg;
211
212 rp->tstate = regs->tstate;
213 rp->tpc = regs->tpc;
214 rp->tnpc = regs->tnpc;
215 rp->o7 = regs->u_regs[UREG_I7];
216
217 if (regs->tstate & TSTATE_PRIV) {
218 struct reg_window *rw;
219
220 rw = (struct reg_window *)
221 (regs->u_regs[UREG_FP] + STACK_BIAS);
222 if (kstack_valid(tp, (unsigned long) rw)) {
223 rp->i7 = rw->ins[7];
224 rw = (struct reg_window *)
225 (rw->ins[6] + STACK_BIAS);
226 if (kstack_valid(tp, (unsigned long) rw))
227 rp->rpc = rw->ins[7];
228 }
229 } else {
230 rp->i7 = 0;
231 rp->rpc = 0;
232 }
233 rp->thread = tp;
234}
235
236/* In order to avoid hangs we do not try to synchronize with the
237 * global register dump client cpus. The last store they make is to
238 * the thread pointer, so do a short poll waiting for that to become
239 * non-NULL.
240 */
241static void __global_reg_poll(struct global_reg_snapshot *gp)
242{
243 int limit = 0;
244
245 while (!gp->thread && ++limit < 100) {
246 barrier();
247 udelay(1);
248 }
249}
250
251void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
252{
253 struct thread_info *tp = current_thread_info();
254 struct pt_regs *regs = get_irq_regs();
255 unsigned long flags;
256 int this_cpu, cpu;
257
258 if (!regs)
259 regs = tp->kregs;
260
261 spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
262
263 this_cpu = raw_smp_processor_id();
264
265 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
266
267 if (cpumask_test_cpu(this_cpu, mask) && !exclude_self)
268 __global_reg_self(tp, regs, this_cpu);
269
270 smp_fetch_global_regs();
271
272 for_each_cpu(cpu, mask) {
273 struct global_reg_snapshot *gp;
274
275 if (exclude_self && cpu == this_cpu)
276 continue;
277
278 gp = &global_cpu_snapshot[cpu].reg;
279
280 __global_reg_poll(gp);
281
282 tp = gp->thread;
283 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
284 (cpu == this_cpu ? '*' : ' '), cpu,
285 gp->tstate, gp->tpc, gp->tnpc,
286 ((tp && tp->task) ? tp->task->comm : "NULL"),
287 ((tp && tp->task) ? tp->task->pid : -1));
288
289 if (gp->tstate & TSTATE_PRIV) {
290 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
291 (void *) gp->tpc,
292 (void *) gp->o7,
293 (void *) gp->i7,
294 (void *) gp->rpc);
295 } else {
296 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
297 gp->tpc, gp->o7, gp->i7, gp->rpc);
298 }
299
300 touch_nmi_watchdog();
301 }
302
303 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
304
305 spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
306}
307
308#ifdef CONFIG_MAGIC_SYSRQ
309
310static void sysrq_handle_globreg(int key)
311{
312 trigger_all_cpu_backtrace();
313}
314
315static const struct sysrq_key_op sparc_globalreg_op = {
316 .handler = sysrq_handle_globreg,
317 .help_msg = "global-regs(y)",
318 .action_msg = "Show Global CPU Regs",
319};
320
321static void __global_pmu_self(int this_cpu)
322{
323 struct global_pmu_snapshot *pp;
324 int i, num;
325
326 if (!pcr_ops)
327 return;
328
329 pp = &global_cpu_snapshot[this_cpu].pmu;
330
331 num = 1;
332 if (tlb_type == hypervisor &&
333 sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
334 num = 4;
335
336 for (i = 0; i < num; i++) {
337 pp->pcr[i] = pcr_ops->read_pcr(i);
338 pp->pic[i] = pcr_ops->read_pic(i);
339 }
340}
341
342static void __global_pmu_poll(struct global_pmu_snapshot *pp)
343{
344 int limit = 0;
345
346 while (!pp->pcr[0] && ++limit < 100) {
347 barrier();
348 udelay(1);
349 }
350}
351
352static void pmu_snapshot_all_cpus(void)
353{
354 unsigned long flags;
355 int this_cpu, cpu;
356
357 spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
358
359 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
360
361 this_cpu = raw_smp_processor_id();
362
363 __global_pmu_self(this_cpu);
364
365 smp_fetch_global_pmu();
366
367 for_each_online_cpu(cpu) {
368 struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
369
370 __global_pmu_poll(pp);
371
372 printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
373 (cpu == this_cpu ? '*' : ' '), cpu,
374 pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
375 pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
376
377 touch_nmi_watchdog();
378 }
379
380 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
381
382 spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
383}
384
385static void sysrq_handle_globpmu(int key)
386{
387 pmu_snapshot_all_cpus();
388}
389
390static const struct sysrq_key_op sparc_globalpmu_op = {
391 .handler = sysrq_handle_globpmu,
392 .help_msg = "global-pmu(x)",
393 .action_msg = "Show Global PMU Regs",
394};
395
396static int __init sparc_sysrq_init(void)
397{
398 int ret = register_sysrq_key('y', &sparc_globalreg_op);
399
400 if (!ret)
401 ret = register_sysrq_key('x', &sparc_globalpmu_op);
402 return ret;
403}
404
405core_initcall(sparc_sysrq_init);
406
407#endif
408
409/* Free current thread data structures etc.. */
410void exit_thread(struct task_struct *tsk)
411{
412 struct thread_info *t = task_thread_info(tsk);
413
414 if (t->utraps) {
415 if (t->utraps[0] < 2)
416 kfree (t->utraps);
417 else
418 t->utraps[0]--;
419 }
420}
421
422void flush_thread(void)
423{
424 struct thread_info *t = current_thread_info();
425 struct mm_struct *mm;
426
427 mm = t->task->mm;
428 if (mm)
429 tsb_context_switch(mm);
430
431 set_thread_wsaved(0);
432
433 /* Clear FPU register state. */
434 t->fpsaved[0] = 0;
435}
436
437/* It's a bit more tricky when 64-bit tasks are involved... */
438static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
439{
440 bool stack_64bit = test_thread_64bit_stack(psp);
441 unsigned long fp, distance, rval;
442
443 if (stack_64bit) {
444 csp += STACK_BIAS;
445 psp += STACK_BIAS;
446 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
447 fp += STACK_BIAS;
448 if (test_thread_flag(TIF_32BIT))
449 fp &= 0xffffffff;
450 } else
451 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
452
453 /* Now align the stack as this is mandatory in the Sparc ABI
454 * due to how register windows work. This hides the
455 * restriction from thread libraries etc.
456 */
457 csp &= ~15UL;
458
459 distance = fp - psp;
460 rval = (csp - distance);
461 if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
462 rval = 0;
463 else if (!stack_64bit) {
464 if (put_user(((u32)csp),
465 &(((struct reg_window32 __user *)rval)->ins[6])))
466 rval = 0;
467 } else {
468 if (put_user(((u64)csp - STACK_BIAS),
469 &(((struct reg_window __user *)rval)->ins[6])))
470 rval = 0;
471 else
472 rval = rval - STACK_BIAS;
473 }
474
475 return rval;
476}
477
478/* Standard stuff. */
479static inline void shift_window_buffer(int first_win, int last_win,
480 struct thread_info *t)
481{
482 int i;
483
484 for (i = first_win; i < last_win; i++) {
485 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
486 memcpy(&t->reg_window[i], &t->reg_window[i+1],
487 sizeof(struct reg_window));
488 }
489}
490
491void synchronize_user_stack(void)
492{
493 struct thread_info *t = current_thread_info();
494 unsigned long window;
495
496 flush_user_windows();
497 if ((window = get_thread_wsaved()) != 0) {
498 window -= 1;
499 do {
500 struct reg_window *rwin = &t->reg_window[window];
501 int winsize = sizeof(struct reg_window);
502 unsigned long sp;
503
504 sp = t->rwbuf_stkptrs[window];
505
506 if (test_thread_64bit_stack(sp))
507 sp += STACK_BIAS;
508 else
509 winsize = sizeof(struct reg_window32);
510
511 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
512 shift_window_buffer(window, get_thread_wsaved() - 1, t);
513 set_thread_wsaved(get_thread_wsaved() - 1);
514 }
515 } while (window--);
516 }
517}
518
519static void stack_unaligned(unsigned long sp)
520{
521 force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp, 0);
522}
523
524static const char uwfault32[] = KERN_INFO \
525 "%s[%d]: bad register window fault: SP %08lx (orig_sp %08lx) TPC %08lx O7 %08lx\n";
526static const char uwfault64[] = KERN_INFO \
527 "%s[%d]: bad register window fault: SP %016lx (orig_sp %016lx) TPC %08lx O7 %016lx\n";
528
529void fault_in_user_windows(struct pt_regs *regs)
530{
531 struct thread_info *t = current_thread_info();
532 unsigned long window;
533
534 flush_user_windows();
535 window = get_thread_wsaved();
536
537 if (likely(window != 0)) {
538 window -= 1;
539 do {
540 struct reg_window *rwin = &t->reg_window[window];
541 int winsize = sizeof(struct reg_window);
542 unsigned long sp, orig_sp;
543
544 orig_sp = sp = t->rwbuf_stkptrs[window];
545
546 if (test_thread_64bit_stack(sp))
547 sp += STACK_BIAS;
548 else
549 winsize = sizeof(struct reg_window32);
550
551 if (unlikely(sp & 0x7UL))
552 stack_unaligned(sp);
553
554 if (unlikely(copy_to_user((char __user *)sp,
555 rwin, winsize))) {
556 if (show_unhandled_signals)
557 printk_ratelimited(is_compat_task() ?
558 uwfault32 : uwfault64,
559 current->comm, current->pid,
560 sp, orig_sp,
561 regs->tpc,
562 regs->u_regs[UREG_I7]);
563 goto barf;
564 }
565 } while (window--);
566 }
567 set_thread_wsaved(0);
568 return;
569
570barf:
571 set_thread_wsaved(window + 1);
572 force_sig(SIGSEGV);
573}
574
575/* Copy a Sparc thread. The fork() return value conventions
576 * under SunOS are nothing short of bletcherous:
577 * Parent --> %o0 == childs pid, %o1 == 0
578 * Child --> %o0 == parents pid, %o1 == 1
579 */
580int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg,
581 struct task_struct *p, unsigned long tls)
582{
583 struct thread_info *t = task_thread_info(p);
584 struct pt_regs *regs = current_pt_regs();
585 struct sparc_stackf *parent_sf;
586 unsigned long child_stack_sz;
587 char *child_trap_frame;
588
589 /* Calculate offset to stack_frame & pt_regs */
590 child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
591 child_trap_frame = (task_stack_page(p) +
592 (THREAD_SIZE - child_stack_sz));
593
594 t->new_child = 1;
595 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
596 t->kregs = (struct pt_regs *) (child_trap_frame +
597 sizeof(struct sparc_stackf));
598 t->fpsaved[0] = 0;
599
600 if (unlikely(p->flags & PF_KTHREAD)) {
601 memset(child_trap_frame, 0, child_stack_sz);
602 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
603 (current_pt_regs()->tstate + 1) & TSTATE_CWP;
604 t->current_ds = ASI_P;
605 t->kregs->u_regs[UREG_G1] = sp; /* function */
606 t->kregs->u_regs[UREG_G2] = arg;
607 return 0;
608 }
609
610 parent_sf = ((struct sparc_stackf *) regs) - 1;
611 memcpy(child_trap_frame, parent_sf, child_stack_sz);
612 if (t->flags & _TIF_32BIT) {
613 sp &= 0x00000000ffffffffUL;
614 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
615 }
616 t->kregs->u_regs[UREG_FP] = sp;
617 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
618 (regs->tstate + 1) & TSTATE_CWP;
619 t->current_ds = ASI_AIUS;
620 if (sp != regs->u_regs[UREG_FP]) {
621 unsigned long csp;
622
623 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
624 if (!csp)
625 return -EFAULT;
626 t->kregs->u_regs[UREG_FP] = csp;
627 }
628 if (t->utraps)
629 t->utraps[0]++;
630
631 /* Set the return value for the child. */
632 t->kregs->u_regs[UREG_I0] = current->pid;
633 t->kregs->u_regs[UREG_I1] = 1;
634
635 /* Set the second return value for the parent. */
636 regs->u_regs[UREG_I1] = 0;
637
638 if (clone_flags & CLONE_SETTLS)
639 t->kregs->u_regs[UREG_G7] = tls;
640
641 return 0;
642}
643
644/* TIF_MCDPER in thread info flags for current task is updated lazily upon
645 * a context switch. Update this flag in current task's thread flags
646 * before dup so the dup'd task will inherit the current TIF_MCDPER flag.
647 */
648int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
649{
650 if (adi_capable()) {
651 register unsigned long tmp_mcdper;
652
653 __asm__ __volatile__(
654 ".word 0x83438000\n\t" /* rd %mcdper, %g1 */
655 "mov %%g1, %0\n\t"
656 : "=r" (tmp_mcdper)
657 :
658 : "g1");
659 if (tmp_mcdper)
660 set_thread_flag(TIF_MCDPER);
661 else
662 clear_thread_flag(TIF_MCDPER);
663 }
664
665 *dst = *src;
666 return 0;
667}
668
669unsigned long get_wchan(struct task_struct *task)
670{
671 unsigned long pc, fp, bias = 0;
672 struct thread_info *tp;
673 struct reg_window *rw;
674 unsigned long ret = 0;
675 int count = 0;
676
677 if (!task || task == current ||
678 task->state == TASK_RUNNING)
679 goto out;
680
681 tp = task_thread_info(task);
682 bias = STACK_BIAS;
683 fp = task_thread_info(task)->ksp + bias;
684
685 do {
686 if (!kstack_valid(tp, fp))
687 break;
688 rw = (struct reg_window *) fp;
689 pc = rw->ins[7];
690 if (!in_sched_functions(pc)) {
691 ret = pc;
692 goto out;
693 }
694 fp = rw->ins[6] + bias;
695 } while (++count < 16);
696
697out:
698 return ret;
699}