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