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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#include <linux/errno.h>
13#include <linux/export.h>
14#include <linux/sched.h>
15#include <linux/sched/debug.h>
16#include <linux/sched/task.h>
17#include <linux/sched/task_stack.h>
18#include <linux/kernel.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/delay.h>
27#include <linux/compat.h>
28#include <linux/tick.h>
29#include <linux/init.h>
30#include <linux/cpu.h>
31#include <linux/perf_event.h>
32#include <linux/elfcore.h>
33#include <linux/sysrq.h>
34#include <linux/nmi.h>
35#include <linux/context_tracking.h>
36#include <linux/signal.h>
37
38#include <linux/uaccess.h>
39#include <asm/page.h>
40#include <asm/pgalloc.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/syscalls.h>
51#include <asm/irq_regs.h>
52#include <asm/smp.h>
53#include <asm/pcr.h>
54
55#include "kstack.h"
56
57/* Idle loop support on sparc64. */
58void arch_cpu_idle(void)
59{
60 if (tlb_type != hypervisor) {
61 touch_nmi_watchdog();
62 raw_local_irq_enable();
63 } else {
64 unsigned long pstate;
65
66 raw_local_irq_enable();
67
68 /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
69 * the cpu sleep hypervisor call.
70 */
71 __asm__ __volatile__(
72 "rdpr %%pstate, %0\n\t"
73 "andn %0, %1, %0\n\t"
74 "wrpr %0, %%g0, %%pstate"
75 : "=&r" (pstate)
76 : "i" (PSTATE_IE));
77
78 if (!need_resched() && !cpu_is_offline(smp_processor_id())) {
79 sun4v_cpu_yield();
80 /* If resumed by cpu_poke then we need to explicitly
81 * call scheduler_ipi().
82 */
83 scheduler_poke();
84 }
85
86 /* Re-enable interrupts. */
87 __asm__ __volatile__(
88 "rdpr %%pstate, %0\n\t"
89 "or %0, %1, %0\n\t"
90 "wrpr %0, %%g0, %%pstate"
91 : "=&r" (pstate)
92 : "i" (PSTATE_IE));
93 }
94}
95
96#ifdef CONFIG_HOTPLUG_CPU
97void arch_cpu_idle_dead(void)
98{
99 sched_preempt_enable_no_resched();
100 cpu_play_dead();
101}
102#endif
103
104#ifdef CONFIG_COMPAT
105static void show_regwindow32(struct pt_regs *regs)
106{
107 struct reg_window32 __user *rw;
108 struct reg_window32 r_w;
109
110 __asm__ __volatile__ ("flushw");
111 rw = compat_ptr((unsigned int)regs->u_regs[14]);
112 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
113 return;
114 }
115
116 printk("l0: %08x l1: %08x l2: %08x l3: %08x "
117 "l4: %08x l5: %08x l6: %08x l7: %08x\n",
118 r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
119 r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
120 printk("i0: %08x i1: %08x i2: %08x i3: %08x "
121 "i4: %08x i5: %08x i6: %08x i7: %08x\n",
122 r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
123 r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
124}
125#else
126#define show_regwindow32(regs) do { } while (0)
127#endif
128
129static void show_regwindow(struct pt_regs *regs)
130{
131 struct reg_window __user *rw;
132 struct reg_window *rwk;
133 struct reg_window r_w;
134
135 if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
136 __asm__ __volatile__ ("flushw");
137 rw = (struct reg_window __user *)
138 (regs->u_regs[14] + STACK_BIAS);
139 rwk = (struct reg_window *)
140 (regs->u_regs[14] + STACK_BIAS);
141 if (!(regs->tstate & TSTATE_PRIV)) {
142 if (copy_from_user (&r_w, rw, sizeof(r_w))) {
143 return;
144 }
145 rwk = &r_w;
146 }
147 } else {
148 show_regwindow32(regs);
149 return;
150 }
151 printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
152 rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
153 printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
154 rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
155 printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
156 rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
157 printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
158 rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
159 if (regs->tstate & TSTATE_PRIV)
160 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
161}
162
163void show_regs(struct pt_regs *regs)
164{
165 show_regs_print_info(KERN_DEFAULT);
166
167 printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x %s\n", regs->tstate,
168 regs->tpc, regs->tnpc, regs->y, print_tainted());
169 printk("TPC: <%pS>\n", (void *) regs->tpc);
170 printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
171 regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
172 regs->u_regs[3]);
173 printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
174 regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
175 regs->u_regs[7]);
176 printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
177 regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
178 regs->u_regs[11]);
179 printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
180 regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
181 regs->u_regs[15]);
182 printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
183 show_regwindow(regs);
184 show_stack(current, (unsigned long *)regs->u_regs[UREG_FP], KERN_DEFAULT);
185}
186
187union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
188static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
189
190static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
191 int this_cpu)
192{
193 struct global_reg_snapshot *rp;
194
195 flushw_all();
196
197 rp = &global_cpu_snapshot[this_cpu].reg;
198
199 rp->tstate = regs->tstate;
200 rp->tpc = regs->tpc;
201 rp->tnpc = regs->tnpc;
202 rp->o7 = regs->u_regs[UREG_I7];
203
204 if (regs->tstate & TSTATE_PRIV) {
205 struct reg_window *rw;
206
207 rw = (struct reg_window *)
208 (regs->u_regs[UREG_FP] + STACK_BIAS);
209 if (kstack_valid(tp, (unsigned long) rw)) {
210 rp->i7 = rw->ins[7];
211 rw = (struct reg_window *)
212 (rw->ins[6] + STACK_BIAS);
213 if (kstack_valid(tp, (unsigned long) rw))
214 rp->rpc = rw->ins[7];
215 }
216 } else {
217 rp->i7 = 0;
218 rp->rpc = 0;
219 }
220 rp->thread = tp;
221}
222
223/* In order to avoid hangs we do not try to synchronize with the
224 * global register dump client cpus. The last store they make is to
225 * the thread pointer, so do a short poll waiting for that to become
226 * non-NULL.
227 */
228static void __global_reg_poll(struct global_reg_snapshot *gp)
229{
230 int limit = 0;
231
232 while (!gp->thread && ++limit < 100) {
233 barrier();
234 udelay(1);
235 }
236}
237
238void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
239{
240 struct thread_info *tp = current_thread_info();
241 struct pt_regs *regs = get_irq_regs();
242 unsigned long flags;
243 int this_cpu, cpu;
244
245 if (!regs)
246 regs = tp->kregs;
247
248 spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
249
250 this_cpu = raw_smp_processor_id();
251
252 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
253
254 if (cpumask_test_cpu(this_cpu, mask) && !exclude_self)
255 __global_reg_self(tp, regs, this_cpu);
256
257 smp_fetch_global_regs();
258
259 for_each_cpu(cpu, mask) {
260 struct global_reg_snapshot *gp;
261
262 if (exclude_self && cpu == this_cpu)
263 continue;
264
265 gp = &global_cpu_snapshot[cpu].reg;
266
267 __global_reg_poll(gp);
268
269 tp = gp->thread;
270 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
271 (cpu == this_cpu ? '*' : ' '), cpu,
272 gp->tstate, gp->tpc, gp->tnpc,
273 ((tp && tp->task) ? tp->task->comm : "NULL"),
274 ((tp && tp->task) ? tp->task->pid : -1));
275
276 if (gp->tstate & TSTATE_PRIV) {
277 printk(" TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
278 (void *) gp->tpc,
279 (void *) gp->o7,
280 (void *) gp->i7,
281 (void *) gp->rpc);
282 } else {
283 printk(" TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
284 gp->tpc, gp->o7, gp->i7, gp->rpc);
285 }
286
287 touch_nmi_watchdog();
288 }
289
290 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
291
292 spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
293}
294
295#ifdef CONFIG_MAGIC_SYSRQ
296
297static void sysrq_handle_globreg(int key)
298{
299 trigger_all_cpu_backtrace();
300}
301
302static const struct sysrq_key_op sparc_globalreg_op = {
303 .handler = sysrq_handle_globreg,
304 .help_msg = "global-regs(y)",
305 .action_msg = "Show Global CPU Regs",
306};
307
308static void __global_pmu_self(int this_cpu)
309{
310 struct global_pmu_snapshot *pp;
311 int i, num;
312
313 if (!pcr_ops)
314 return;
315
316 pp = &global_cpu_snapshot[this_cpu].pmu;
317
318 num = 1;
319 if (tlb_type == hypervisor &&
320 sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
321 num = 4;
322
323 for (i = 0; i < num; i++) {
324 pp->pcr[i] = pcr_ops->read_pcr(i);
325 pp->pic[i] = pcr_ops->read_pic(i);
326 }
327}
328
329static void __global_pmu_poll(struct global_pmu_snapshot *pp)
330{
331 int limit = 0;
332
333 while (!pp->pcr[0] && ++limit < 100) {
334 barrier();
335 udelay(1);
336 }
337}
338
339static void pmu_snapshot_all_cpus(void)
340{
341 unsigned long flags;
342 int this_cpu, cpu;
343
344 spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
345
346 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
347
348 this_cpu = raw_smp_processor_id();
349
350 __global_pmu_self(this_cpu);
351
352 smp_fetch_global_pmu();
353
354 for_each_online_cpu(cpu) {
355 struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
356
357 __global_pmu_poll(pp);
358
359 printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
360 (cpu == this_cpu ? '*' : ' '), cpu,
361 pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
362 pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
363
364 touch_nmi_watchdog();
365 }
366
367 memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
368
369 spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
370}
371
372static void sysrq_handle_globpmu(int key)
373{
374 pmu_snapshot_all_cpus();
375}
376
377static const struct sysrq_key_op sparc_globalpmu_op = {
378 .handler = sysrq_handle_globpmu,
379 .help_msg = "global-pmu(x)",
380 .action_msg = "Show Global PMU Regs",
381};
382
383static int __init sparc_sysrq_init(void)
384{
385 int ret = register_sysrq_key('y', &sparc_globalreg_op);
386
387 if (!ret)
388 ret = register_sysrq_key('x', &sparc_globalpmu_op);
389 return ret;
390}
391
392core_initcall(sparc_sysrq_init);
393
394#endif
395
396/* Free current thread data structures etc.. */
397void exit_thread(struct task_struct *tsk)
398{
399 struct thread_info *t = task_thread_info(tsk);
400
401 if (t->utraps) {
402 if (t->utraps[0] < 2)
403 kfree (t->utraps);
404 else
405 t->utraps[0]--;
406 }
407}
408
409void flush_thread(void)
410{
411 struct thread_info *t = current_thread_info();
412 struct mm_struct *mm;
413
414 mm = t->task->mm;
415 if (mm)
416 tsb_context_switch(mm);
417
418 set_thread_wsaved(0);
419
420 /* Clear FPU register state. */
421 t->fpsaved[0] = 0;
422}
423
424/* It's a bit more tricky when 64-bit tasks are involved... */
425static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
426{
427 bool stack_64bit = test_thread_64bit_stack(psp);
428 unsigned long fp, distance, rval;
429
430 if (stack_64bit) {
431 csp += STACK_BIAS;
432 psp += STACK_BIAS;
433 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
434 fp += STACK_BIAS;
435 if (test_thread_flag(TIF_32BIT))
436 fp &= 0xffffffff;
437 } else
438 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
439
440 /* Now align the stack as this is mandatory in the Sparc ABI
441 * due to how register windows work. This hides the
442 * restriction from thread libraries etc.
443 */
444 csp &= ~15UL;
445
446 distance = fp - psp;
447 rval = (csp - distance);
448 if (raw_copy_in_user((void __user *)rval, (void __user *)psp, distance))
449 rval = 0;
450 else if (!stack_64bit) {
451 if (put_user(((u32)csp),
452 &(((struct reg_window32 __user *)rval)->ins[6])))
453 rval = 0;
454 } else {
455 if (put_user(((u64)csp - STACK_BIAS),
456 &(((struct reg_window __user *)rval)->ins[6])))
457 rval = 0;
458 else
459 rval = rval - STACK_BIAS;
460 }
461
462 return rval;
463}
464
465/* Standard stuff. */
466static inline void shift_window_buffer(int first_win, int last_win,
467 struct thread_info *t)
468{
469 int i;
470
471 for (i = first_win; i < last_win; i++) {
472 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
473 memcpy(&t->reg_window[i], &t->reg_window[i+1],
474 sizeof(struct reg_window));
475 }
476}
477
478void synchronize_user_stack(void)
479{
480 struct thread_info *t = current_thread_info();
481 unsigned long window;
482
483 flush_user_windows();
484 if ((window = get_thread_wsaved()) != 0) {
485 window -= 1;
486 do {
487 struct reg_window *rwin = &t->reg_window[window];
488 int winsize = sizeof(struct reg_window);
489 unsigned long sp;
490
491 sp = t->rwbuf_stkptrs[window];
492
493 if (test_thread_64bit_stack(sp))
494 sp += STACK_BIAS;
495 else
496 winsize = sizeof(struct reg_window32);
497
498 if (!copy_to_user((char __user *)sp, rwin, winsize)) {
499 shift_window_buffer(window, get_thread_wsaved() - 1, t);
500 set_thread_wsaved(get_thread_wsaved() - 1);
501 }
502 } while (window--);
503 }
504}
505
506static void stack_unaligned(unsigned long sp)
507{
508 force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp);
509}
510
511static const char uwfault32[] = KERN_INFO \
512 "%s[%d]: bad register window fault: SP %08lx (orig_sp %08lx) TPC %08lx O7 %08lx\n";
513static const char uwfault64[] = KERN_INFO \
514 "%s[%d]: bad register window fault: SP %016lx (orig_sp %016lx) TPC %08lx O7 %016lx\n";
515
516void fault_in_user_windows(struct pt_regs *regs)
517{
518 struct thread_info *t = current_thread_info();
519 unsigned long window;
520
521 flush_user_windows();
522 window = get_thread_wsaved();
523
524 if (likely(window != 0)) {
525 window -= 1;
526 do {
527 struct reg_window *rwin = &t->reg_window[window];
528 int winsize = sizeof(struct reg_window);
529 unsigned long sp, orig_sp;
530
531 orig_sp = sp = t->rwbuf_stkptrs[window];
532
533 if (test_thread_64bit_stack(sp))
534 sp += STACK_BIAS;
535 else
536 winsize = sizeof(struct reg_window32);
537
538 if (unlikely(sp & 0x7UL))
539 stack_unaligned(sp);
540
541 if (unlikely(copy_to_user((char __user *)sp,
542 rwin, winsize))) {
543 if (show_unhandled_signals)
544 printk_ratelimited(is_compat_task() ?
545 uwfault32 : uwfault64,
546 current->comm, current->pid,
547 sp, orig_sp,
548 regs->tpc,
549 regs->u_regs[UREG_I7]);
550 goto barf;
551 }
552 } while (window--);
553 }
554 set_thread_wsaved(0);
555 return;
556
557barf:
558 set_thread_wsaved(window + 1);
559 force_sig(SIGSEGV);
560}
561
562/* Copy a Sparc thread. The fork() return value conventions
563 * under SunOS are nothing short of bletcherous:
564 * Parent --> %o0 == childs pid, %o1 == 0
565 * Child --> %o0 == parents pid, %o1 == 1
566 */
567int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
568{
569 unsigned long clone_flags = args->flags;
570 unsigned long sp = args->stack;
571 unsigned long tls = args->tls;
572 struct thread_info *t = task_thread_info(p);
573 struct pt_regs *regs = current_pt_regs();
574 struct sparc_stackf *parent_sf;
575 unsigned long child_stack_sz;
576 char *child_trap_frame;
577
578 /* Calculate offset to stack_frame & pt_regs */
579 child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
580 child_trap_frame = (task_stack_page(p) +
581 (THREAD_SIZE - child_stack_sz));
582
583 t->new_child = 1;
584 t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
585 t->kregs = (struct pt_regs *) (child_trap_frame +
586 sizeof(struct sparc_stackf));
587 t->fpsaved[0] = 0;
588
589 if (unlikely(args->fn)) {
590 memset(child_trap_frame, 0, child_stack_sz);
591 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
592 (current_pt_regs()->tstate + 1) & TSTATE_CWP;
593 t->kregs->u_regs[UREG_G1] = (unsigned long) args->fn;
594 t->kregs->u_regs[UREG_G2] = (unsigned long) args->fn_arg;
595 return 0;
596 }
597
598 parent_sf = ((struct sparc_stackf *) regs) - 1;
599 memcpy(child_trap_frame, parent_sf, child_stack_sz);
600 if (t->flags & _TIF_32BIT) {
601 sp &= 0x00000000ffffffffUL;
602 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
603 }
604 t->kregs->u_regs[UREG_FP] = sp;
605 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] =
606 (regs->tstate + 1) & TSTATE_CWP;
607 if (sp != regs->u_regs[UREG_FP]) {
608 unsigned long csp;
609
610 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
611 if (!csp)
612 return -EFAULT;
613 t->kregs->u_regs[UREG_FP] = csp;
614 }
615 if (t->utraps)
616 t->utraps[0]++;
617
618 /* Set the return value for the child. */
619 t->kregs->u_regs[UREG_I0] = current->pid;
620 t->kregs->u_regs[UREG_I1] = 1;
621
622 /* Set the second return value for the parent. */
623 regs->u_regs[UREG_I1] = 0;
624
625 if (clone_flags & CLONE_SETTLS)
626 t->kregs->u_regs[UREG_G7] = tls;
627
628 return 0;
629}
630
631/* TIF_MCDPER in thread info flags for current task is updated lazily upon
632 * a context switch. Update this flag in current task's thread flags
633 * before dup so the dup'd task will inherit the current TIF_MCDPER flag.
634 */
635int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
636{
637 if (adi_capable()) {
638 register unsigned long tmp_mcdper;
639
640 __asm__ __volatile__(
641 ".word 0x83438000\n\t" /* rd %mcdper, %g1 */
642 "mov %%g1, %0\n\t"
643 : "=r" (tmp_mcdper)
644 :
645 : "g1");
646 if (tmp_mcdper)
647 set_thread_flag(TIF_MCDPER);
648 else
649 clear_thread_flag(TIF_MCDPER);
650 }
651
652 *dst = *src;
653 return 0;
654}
655
656unsigned long __get_wchan(struct task_struct *task)
657{
658 unsigned long pc, fp, bias = 0;
659 struct thread_info *tp;
660 struct reg_window *rw;
661 unsigned long ret = 0;
662 int count = 0;
663
664 tp = task_thread_info(task);
665 bias = STACK_BIAS;
666 fp = task_thread_info(task)->ksp + bias;
667
668 do {
669 if (!kstack_valid(tp, fp))
670 break;
671 rw = (struct reg_window *) fp;
672 pc = rw->ins[7];
673 if (!in_sched_functions(pc)) {
674 ret = pc;
675 goto out;
676 }
677 fp = rw->ins[6] + bias;
678 } while (++count < 16);
679
680out:
681 return ret;
682}