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1// SPDX-License-Identifier: GPL-2.0
2/* linux/arch/sparc/kernel/process.c
3 *
4 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
5 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
6 */
7
8/*
9 * This file handles the architecture-dependent parts of process handling..
10 */
11
12#include <stdarg.h>
13
14#include <linux/elfcore.h>
15#include <linux/errno.h>
16#include <linux/module.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/stddef.h>
24#include <linux/ptrace.h>
25#include <linux/user.h>
26#include <linux/smp.h>
27#include <linux/reboot.h>
28#include <linux/delay.h>
29#include <linux/pm.h>
30#include <linux/slab.h>
31#include <linux/cpu.h>
32
33#include <asm/auxio.h>
34#include <asm/oplib.h>
35#include <linux/uaccess.h>
36#include <asm/page.h>
37#include <asm/pgalloc.h>
38#include <asm/pgtable.h>
39#include <asm/delay.h>
40#include <asm/processor.h>
41#include <asm/psr.h>
42#include <asm/elf.h>
43#include <asm/prom.h>
44#include <asm/unistd.h>
45#include <asm/setup.h>
46
47#include "kernel.h"
48
49/*
50 * Power management idle function
51 * Set in pm platform drivers (apc.c and pmc.c)
52 */
53void (*sparc_idle)(void);
54
55/*
56 * Power-off handler instantiation for pm.h compliance
57 * This is done via auxio, but could be used as a fallback
58 * handler when auxio is not present-- unused for now...
59 */
60void (*pm_power_off)(void) = machine_power_off;
61EXPORT_SYMBOL(pm_power_off);
62
63/*
64 * sysctl - toggle power-off restriction for serial console
65 * systems in machine_power_off()
66 */
67int scons_pwroff = 1;
68
69extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);
70
71struct task_struct *last_task_used_math = NULL;
72struct thread_info *current_set[NR_CPUS];
73
74/* Idle loop support. */
75void arch_cpu_idle(void)
76{
77 if (sparc_idle)
78 (*sparc_idle)();
79 local_irq_enable();
80}
81
82/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
83void machine_halt(void)
84{
85 local_irq_enable();
86 mdelay(8);
87 local_irq_disable();
88 prom_halt();
89 panic("Halt failed!");
90}
91
92void machine_restart(char * cmd)
93{
94 char *p;
95
96 local_irq_enable();
97 mdelay(8);
98 local_irq_disable();
99
100 p = strchr (reboot_command, '\n');
101 if (p) *p = 0;
102 if (cmd)
103 prom_reboot(cmd);
104 if (*reboot_command)
105 prom_reboot(reboot_command);
106 prom_feval ("reset");
107 panic("Reboot failed!");
108}
109
110void machine_power_off(void)
111{
112 if (auxio_power_register &&
113 (strcmp(of_console_device->type, "serial") || scons_pwroff)) {
114 u8 power_register = sbus_readb(auxio_power_register);
115 power_register |= AUXIO_POWER_OFF;
116 sbus_writeb(power_register, auxio_power_register);
117 }
118
119 machine_halt();
120}
121
122void show_regs(struct pt_regs *r)
123{
124 struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14];
125
126 show_regs_print_info(KERN_DEFAULT);
127
128 printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
129 r->psr, r->pc, r->npc, r->y, print_tainted());
130 printk("PC: <%pS>\n", (void *) r->pc);
131 printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
132 r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
133 r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
134 printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
135 r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
136 r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
137 printk("RPC: <%pS>\n", (void *) r->u_regs[15]);
138
139 printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
140 rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
141 rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
142 printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
143 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
144 rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
145}
146
147/*
148 * The show_stack is an external API which we do not use ourselves.
149 * The oops is printed in die_if_kernel.
150 */
151void show_stack(struct task_struct *tsk, unsigned long *_ksp)
152{
153 unsigned long pc, fp;
154 unsigned long task_base;
155 struct reg_window32 *rw;
156 int count = 0;
157
158 if (!tsk)
159 tsk = current;
160
161 if (tsk == current && !_ksp)
162 __asm__ __volatile__("mov %%fp, %0" : "=r" (_ksp));
163
164 task_base = (unsigned long) task_stack_page(tsk);
165 fp = (unsigned long) _ksp;
166 do {
167 /* Bogus frame pointer? */
168 if (fp < (task_base + sizeof(struct thread_info)) ||
169 fp >= (task_base + (PAGE_SIZE << 1)))
170 break;
171 rw = (struct reg_window32 *) fp;
172 pc = rw->ins[7];
173 printk("[%08lx : ", pc);
174 printk("%pS ] ", (void *) pc);
175 fp = rw->ins[6];
176 } while (++count < 16);
177 printk("\n");
178}
179
180/*
181 * Free current thread data structures etc..
182 */
183void exit_thread(struct task_struct *tsk)
184{
185#ifndef CONFIG_SMP
186 if (last_task_used_math == tsk) {
187#else
188 if (test_ti_thread_flag(task_thread_info(tsk), TIF_USEDFPU)) {
189#endif
190 /* Keep process from leaving FPU in a bogon state. */
191 put_psr(get_psr() | PSR_EF);
192 fpsave(&tsk->thread.float_regs[0], &tsk->thread.fsr,
193 &tsk->thread.fpqueue[0], &tsk->thread.fpqdepth);
194#ifndef CONFIG_SMP
195 last_task_used_math = NULL;
196#else
197 clear_ti_thread_flag(task_thread_info(tsk), TIF_USEDFPU);
198#endif
199 }
200}
201
202void flush_thread(void)
203{
204 current_thread_info()->w_saved = 0;
205
206#ifndef CONFIG_SMP
207 if(last_task_used_math == current) {
208#else
209 if (test_thread_flag(TIF_USEDFPU)) {
210#endif
211 /* Clean the fpu. */
212 put_psr(get_psr() | PSR_EF);
213 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
214 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
215#ifndef CONFIG_SMP
216 last_task_used_math = NULL;
217#else
218 clear_thread_flag(TIF_USEDFPU);
219#endif
220 }
221
222 /* This task is no longer a kernel thread. */
223 if (current->thread.flags & SPARC_FLAG_KTHREAD) {
224 current->thread.flags &= ~SPARC_FLAG_KTHREAD;
225
226 /* We must fixup kregs as well. */
227 /* XXX This was not fixed for ti for a while, worked. Unused? */
228 current->thread.kregs = (struct pt_regs *)
229 (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
230 }
231}
232
233static inline struct sparc_stackf __user *
234clone_stackframe(struct sparc_stackf __user *dst,
235 struct sparc_stackf __user *src)
236{
237 unsigned long size, fp;
238 struct sparc_stackf *tmp;
239 struct sparc_stackf __user *sp;
240
241 if (get_user(tmp, &src->fp))
242 return NULL;
243
244 fp = (unsigned long) tmp;
245 size = (fp - ((unsigned long) src));
246 fp = (unsigned long) dst;
247 sp = (struct sparc_stackf __user *)(fp - size);
248
249 /* do_fork() grabs the parent semaphore, we must release it
250 * temporarily so we can build the child clone stack frame
251 * without deadlocking.
252 */
253 if (__copy_user(sp, src, size))
254 sp = NULL;
255 else if (put_user(fp, &sp->fp))
256 sp = NULL;
257
258 return sp;
259}
260
261asmlinkage int sparc_do_fork(unsigned long clone_flags,
262 unsigned long stack_start,
263 struct pt_regs *regs,
264 unsigned long stack_size)
265{
266 unsigned long parent_tid_ptr, child_tid_ptr;
267 unsigned long orig_i1 = regs->u_regs[UREG_I1];
268 long ret;
269
270 parent_tid_ptr = regs->u_regs[UREG_I2];
271 child_tid_ptr = regs->u_regs[UREG_I4];
272
273 ret = do_fork(clone_flags, stack_start, stack_size,
274 (int __user *) parent_tid_ptr,
275 (int __user *) child_tid_ptr);
276
277 /* If we get an error and potentially restart the system
278 * call, we're screwed because copy_thread() clobbered
279 * the parent's %o1. So detect that case and restore it
280 * here.
281 */
282 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
283 regs->u_regs[UREG_I1] = orig_i1;
284
285 return ret;
286}
287
288/* Copy a Sparc thread. The fork() return value conventions
289 * under SunOS are nothing short of bletcherous:
290 * Parent --> %o0 == childs pid, %o1 == 0
291 * Child --> %o0 == parents pid, %o1 == 1
292 *
293 * NOTE: We have a separate fork kpsr/kwim because
294 * the parent could change these values between
295 * sys_fork invocation and when we reach here
296 * if the parent should sleep while trying to
297 * allocate the task_struct and kernel stack in
298 * do_fork().
299 * XXX See comment above sys_vfork in sparc64. todo.
300 */
301extern void ret_from_fork(void);
302extern void ret_from_kernel_thread(void);
303
304int copy_thread(unsigned long clone_flags, unsigned long sp,
305 unsigned long arg, struct task_struct *p)
306{
307 struct thread_info *ti = task_thread_info(p);
308 struct pt_regs *childregs, *regs = current_pt_regs();
309 char *new_stack;
310
311#ifndef CONFIG_SMP
312 if(last_task_used_math == current) {
313#else
314 if (test_thread_flag(TIF_USEDFPU)) {
315#endif
316 put_psr(get_psr() | PSR_EF);
317 fpsave(&p->thread.float_regs[0], &p->thread.fsr,
318 &p->thread.fpqueue[0], &p->thread.fpqdepth);
319 }
320
321 /*
322 * p->thread_info new_stack childregs stack bottom
323 * ! ! ! !
324 * V V (stk.fr.) V (pt_regs) V
325 * +----- - - - - - ------+===========+=============+
326 */
327 new_stack = task_stack_page(p) + THREAD_SIZE;
328 new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
329 childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
330
331 /*
332 * A new process must start with interrupts disabled, see schedule_tail()
333 * and finish_task_switch(). (If we do not do it and if a timer interrupt
334 * hits before we unlock and attempts to take the rq->lock, we deadlock.)
335 *
336 * Thus, kpsr |= PSR_PIL.
337 */
338 ti->ksp = (unsigned long) new_stack;
339 p->thread.kregs = childregs;
340
341 if (unlikely(p->flags & PF_KTHREAD)) {
342 extern int nwindows;
343 unsigned long psr;
344 memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
345 p->thread.flags |= SPARC_FLAG_KTHREAD;
346 p->thread.current_ds = KERNEL_DS;
347 ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
348 childregs->u_regs[UREG_G1] = sp; /* function */
349 childregs->u_regs[UREG_G2] = arg;
350 psr = childregs->psr = get_psr();
351 ti->kpsr = psr | PSR_PIL;
352 ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
353 return 0;
354 }
355 memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
356 childregs->u_regs[UREG_FP] = sp;
357 p->thread.flags &= ~SPARC_FLAG_KTHREAD;
358 p->thread.current_ds = USER_DS;
359 ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
360 ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
361 ti->kwim = current->thread.fork_kwim;
362
363 if (sp != regs->u_regs[UREG_FP]) {
364 struct sparc_stackf __user *childstack;
365 struct sparc_stackf __user *parentstack;
366
367 /*
368 * This is a clone() call with supplied user stack.
369 * Set some valid stack frames to give to the child.
370 */
371 childstack = (struct sparc_stackf __user *)
372 (sp & ~0xfUL);
373 parentstack = (struct sparc_stackf __user *)
374 regs->u_regs[UREG_FP];
375
376#if 0
377 printk("clone: parent stack:\n");
378 show_stackframe(parentstack);
379#endif
380
381 childstack = clone_stackframe(childstack, parentstack);
382 if (!childstack)
383 return -EFAULT;
384
385#if 0
386 printk("clone: child stack:\n");
387 show_stackframe(childstack);
388#endif
389
390 childregs->u_regs[UREG_FP] = (unsigned long)childstack;
391 }
392
393#ifdef CONFIG_SMP
394 /* FPU must be disabled on SMP. */
395 childregs->psr &= ~PSR_EF;
396 clear_tsk_thread_flag(p, TIF_USEDFPU);
397#endif
398
399 /* Set the return value for the child. */
400 childregs->u_regs[UREG_I0] = current->pid;
401 childregs->u_regs[UREG_I1] = 1;
402
403 /* Set the return value for the parent. */
404 regs->u_regs[UREG_I1] = 0;
405
406 if (clone_flags & CLONE_SETTLS)
407 childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
408
409 return 0;
410}
411
412/*
413 * fill in the fpu structure for a core dump.
414 */
415int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
416{
417 if (used_math()) {
418 memset(fpregs, 0, sizeof(*fpregs));
419 fpregs->pr_q_entrysize = 8;
420 return 1;
421 }
422#ifdef CONFIG_SMP
423 if (test_thread_flag(TIF_USEDFPU)) {
424 put_psr(get_psr() | PSR_EF);
425 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
426 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
427 if (regs != NULL) {
428 regs->psr &= ~(PSR_EF);
429 clear_thread_flag(TIF_USEDFPU);
430 }
431 }
432#else
433 if (current == last_task_used_math) {
434 put_psr(get_psr() | PSR_EF);
435 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
436 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
437 if (regs != NULL) {
438 regs->psr &= ~(PSR_EF);
439 last_task_used_math = NULL;
440 }
441 }
442#endif
443 memcpy(&fpregs->pr_fr.pr_regs[0],
444 ¤t->thread.float_regs[0],
445 (sizeof(unsigned long) * 32));
446 fpregs->pr_fsr = current->thread.fsr;
447 fpregs->pr_qcnt = current->thread.fpqdepth;
448 fpregs->pr_q_entrysize = 8;
449 fpregs->pr_en = 1;
450 if(fpregs->pr_qcnt != 0) {
451 memcpy(&fpregs->pr_q[0],
452 ¤t->thread.fpqueue[0],
453 sizeof(struct fpq) * fpregs->pr_qcnt);
454 }
455 /* Zero out the rest. */
456 memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
457 sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
458 return 1;
459}
460
461unsigned long get_wchan(struct task_struct *task)
462{
463 unsigned long pc, fp, bias = 0;
464 unsigned long task_base = (unsigned long) task;
465 unsigned long ret = 0;
466 struct reg_window32 *rw;
467 int count = 0;
468
469 if (!task || task == current ||
470 task->state == TASK_RUNNING)
471 goto out;
472
473 fp = task_thread_info(task)->ksp + bias;
474 do {
475 /* Bogus frame pointer? */
476 if (fp < (task_base + sizeof(struct thread_info)) ||
477 fp >= (task_base + (2 * PAGE_SIZE)))
478 break;
479 rw = (struct reg_window32 *) fp;
480 pc = rw->ins[7];
481 if (!in_sched_functions(pc)) {
482 ret = pc;
483 goto out;
484 }
485 fp = rw->ins[6] + bias;
486 } while (++count < 16);
487
488out:
489 return ret;
490}
491
1/* linux/arch/sparc/kernel/process.c
2 *
3 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
5 */
6
7/*
8 * This file handles the architecture-dependent parts of process handling..
9 */
10
11#include <stdarg.h>
12
13#include <linux/errno.h>
14#include <linux/module.h>
15#include <linux/sched.h>
16#include <linux/kernel.h>
17#include <linux/mm.h>
18#include <linux/stddef.h>
19#include <linux/ptrace.h>
20#include <linux/user.h>
21#include <linux/smp.h>
22#include <linux/reboot.h>
23#include <linux/delay.h>
24#include <linux/pm.h>
25#include <linux/slab.h>
26
27#include <asm/auxio.h>
28#include <asm/oplib.h>
29#include <asm/uaccess.h>
30#include <asm/page.h>
31#include <asm/pgalloc.h>
32#include <asm/pgtable.h>
33#include <asm/delay.h>
34#include <asm/processor.h>
35#include <asm/psr.h>
36#include <asm/elf.h>
37#include <asm/prom.h>
38#include <asm/unistd.h>
39#include <asm/setup.h>
40
41/*
42 * Power management idle function
43 * Set in pm platform drivers (apc.c and pmc.c)
44 */
45void (*sparc_idle)(void);
46
47/*
48 * Power-off handler instantiation for pm.h compliance
49 * This is done via auxio, but could be used as a fallback
50 * handler when auxio is not present-- unused for now...
51 */
52void (*pm_power_off)(void) = machine_power_off;
53EXPORT_SYMBOL(pm_power_off);
54
55/*
56 * sysctl - toggle power-off restriction for serial console
57 * systems in machine_power_off()
58 */
59int scons_pwroff = 1;
60
61extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);
62
63struct task_struct *last_task_used_math = NULL;
64struct thread_info *current_set[NR_CPUS];
65
66/* Idle loop support. */
67void arch_cpu_idle(void)
68{
69 if (sparc_idle)
70 (*sparc_idle)();
71 local_irq_enable();
72}
73
74/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
75void machine_halt(void)
76{
77 local_irq_enable();
78 mdelay(8);
79 local_irq_disable();
80 prom_halt();
81 panic("Halt failed!");
82}
83
84void machine_restart(char * cmd)
85{
86 char *p;
87
88 local_irq_enable();
89 mdelay(8);
90 local_irq_disable();
91
92 p = strchr (reboot_command, '\n');
93 if (p) *p = 0;
94 if (cmd)
95 prom_reboot(cmd);
96 if (*reboot_command)
97 prom_reboot(reboot_command);
98 prom_feval ("reset");
99 panic("Reboot failed!");
100}
101
102void machine_power_off(void)
103{
104 if (auxio_power_register &&
105 (strcmp(of_console_device->type, "serial") || scons_pwroff))
106 *auxio_power_register |= AUXIO_POWER_OFF;
107 machine_halt();
108}
109
110void show_regs(struct pt_regs *r)
111{
112 struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14];
113
114 show_regs_print_info(KERN_DEFAULT);
115
116 printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
117 r->psr, r->pc, r->npc, r->y, print_tainted());
118 printk("PC: <%pS>\n", (void *) r->pc);
119 printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
120 r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
121 r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
122 printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
123 r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
124 r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
125 printk("RPC: <%pS>\n", (void *) r->u_regs[15]);
126
127 printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
128 rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
129 rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
130 printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
131 rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
132 rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
133}
134
135/*
136 * The show_stack is an external API which we do not use ourselves.
137 * The oops is printed in die_if_kernel.
138 */
139void show_stack(struct task_struct *tsk, unsigned long *_ksp)
140{
141 unsigned long pc, fp;
142 unsigned long task_base;
143 struct reg_window32 *rw;
144 int count = 0;
145
146 if (!tsk)
147 tsk = current;
148
149 if (tsk == current && !_ksp)
150 __asm__ __volatile__("mov %%fp, %0" : "=r" (_ksp));
151
152 task_base = (unsigned long) task_stack_page(tsk);
153 fp = (unsigned long) _ksp;
154 do {
155 /* Bogus frame pointer? */
156 if (fp < (task_base + sizeof(struct thread_info)) ||
157 fp >= (task_base + (PAGE_SIZE << 1)))
158 break;
159 rw = (struct reg_window32 *) fp;
160 pc = rw->ins[7];
161 printk("[%08lx : ", pc);
162 printk("%pS ] ", (void *) pc);
163 fp = rw->ins[6];
164 } while (++count < 16);
165 printk("\n");
166}
167
168/*
169 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
170 */
171unsigned long thread_saved_pc(struct task_struct *tsk)
172{
173 return task_thread_info(tsk)->kpc;
174}
175
176/*
177 * Free current thread data structures etc..
178 */
179void exit_thread(void)
180{
181#ifndef CONFIG_SMP
182 if(last_task_used_math == current) {
183#else
184 if (test_thread_flag(TIF_USEDFPU)) {
185#endif
186 /* Keep process from leaving FPU in a bogon state. */
187 put_psr(get_psr() | PSR_EF);
188 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
189 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
190#ifndef CONFIG_SMP
191 last_task_used_math = NULL;
192#else
193 clear_thread_flag(TIF_USEDFPU);
194#endif
195 }
196}
197
198void flush_thread(void)
199{
200 current_thread_info()->w_saved = 0;
201
202#ifndef CONFIG_SMP
203 if(last_task_used_math == current) {
204#else
205 if (test_thread_flag(TIF_USEDFPU)) {
206#endif
207 /* Clean the fpu. */
208 put_psr(get_psr() | PSR_EF);
209 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
210 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
211#ifndef CONFIG_SMP
212 last_task_used_math = NULL;
213#else
214 clear_thread_flag(TIF_USEDFPU);
215#endif
216 }
217
218 /* This task is no longer a kernel thread. */
219 if (current->thread.flags & SPARC_FLAG_KTHREAD) {
220 current->thread.flags &= ~SPARC_FLAG_KTHREAD;
221
222 /* We must fixup kregs as well. */
223 /* XXX This was not fixed for ti for a while, worked. Unused? */
224 current->thread.kregs = (struct pt_regs *)
225 (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
226 }
227}
228
229static inline struct sparc_stackf __user *
230clone_stackframe(struct sparc_stackf __user *dst,
231 struct sparc_stackf __user *src)
232{
233 unsigned long size, fp;
234 struct sparc_stackf *tmp;
235 struct sparc_stackf __user *sp;
236
237 if (get_user(tmp, &src->fp))
238 return NULL;
239
240 fp = (unsigned long) tmp;
241 size = (fp - ((unsigned long) src));
242 fp = (unsigned long) dst;
243 sp = (struct sparc_stackf __user *)(fp - size);
244
245 /* do_fork() grabs the parent semaphore, we must release it
246 * temporarily so we can build the child clone stack frame
247 * without deadlocking.
248 */
249 if (__copy_user(sp, src, size))
250 sp = NULL;
251 else if (put_user(fp, &sp->fp))
252 sp = NULL;
253
254 return sp;
255}
256
257asmlinkage int sparc_do_fork(unsigned long clone_flags,
258 unsigned long stack_start,
259 struct pt_regs *regs,
260 unsigned long stack_size)
261{
262 unsigned long parent_tid_ptr, child_tid_ptr;
263 unsigned long orig_i1 = regs->u_regs[UREG_I1];
264 long ret;
265
266 parent_tid_ptr = regs->u_regs[UREG_I2];
267 child_tid_ptr = regs->u_regs[UREG_I4];
268
269 ret = do_fork(clone_flags, stack_start, stack_size,
270 (int __user *) parent_tid_ptr,
271 (int __user *) child_tid_ptr);
272
273 /* If we get an error and potentially restart the system
274 * call, we're screwed because copy_thread() clobbered
275 * the parent's %o1. So detect that case and restore it
276 * here.
277 */
278 if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
279 regs->u_regs[UREG_I1] = orig_i1;
280
281 return ret;
282}
283
284/* Copy a Sparc thread. The fork() return value conventions
285 * under SunOS are nothing short of bletcherous:
286 * Parent --> %o0 == childs pid, %o1 == 0
287 * Child --> %o0 == parents pid, %o1 == 1
288 *
289 * NOTE: We have a separate fork kpsr/kwim because
290 * the parent could change these values between
291 * sys_fork invocation and when we reach here
292 * if the parent should sleep while trying to
293 * allocate the task_struct and kernel stack in
294 * do_fork().
295 * XXX See comment above sys_vfork in sparc64. todo.
296 */
297extern void ret_from_fork(void);
298extern void ret_from_kernel_thread(void);
299
300int copy_thread(unsigned long clone_flags, unsigned long sp,
301 unsigned long arg, struct task_struct *p)
302{
303 struct thread_info *ti = task_thread_info(p);
304 struct pt_regs *childregs, *regs = current_pt_regs();
305 char *new_stack;
306
307#ifndef CONFIG_SMP
308 if(last_task_used_math == current) {
309#else
310 if (test_thread_flag(TIF_USEDFPU)) {
311#endif
312 put_psr(get_psr() | PSR_EF);
313 fpsave(&p->thread.float_regs[0], &p->thread.fsr,
314 &p->thread.fpqueue[0], &p->thread.fpqdepth);
315 }
316
317 /*
318 * p->thread_info new_stack childregs stack bottom
319 * ! ! ! !
320 * V V (stk.fr.) V (pt_regs) V
321 * +----- - - - - - ------+===========+=============+
322 */
323 new_stack = task_stack_page(p) + THREAD_SIZE;
324 new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
325 childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
326
327 /*
328 * A new process must start with interrupts closed in 2.5,
329 * because this is how Mingo's scheduler works (see schedule_tail
330 * and finish_arch_switch). If we do not do it, a timer interrupt hits
331 * before we unlock, attempts to re-take the rq->lock, and then we die.
332 * Thus, kpsr|=PSR_PIL.
333 */
334 ti->ksp = (unsigned long) new_stack;
335 p->thread.kregs = childregs;
336
337 if (unlikely(p->flags & PF_KTHREAD)) {
338 extern int nwindows;
339 unsigned long psr;
340 memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
341 p->thread.flags |= SPARC_FLAG_KTHREAD;
342 p->thread.current_ds = KERNEL_DS;
343 ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
344 childregs->u_regs[UREG_G1] = sp; /* function */
345 childregs->u_regs[UREG_G2] = arg;
346 psr = childregs->psr = get_psr();
347 ti->kpsr = psr | PSR_PIL;
348 ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
349 return 0;
350 }
351 memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
352 childregs->u_regs[UREG_FP] = sp;
353 p->thread.flags &= ~SPARC_FLAG_KTHREAD;
354 p->thread.current_ds = USER_DS;
355 ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
356 ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
357 ti->kwim = current->thread.fork_kwim;
358
359 if (sp != regs->u_regs[UREG_FP]) {
360 struct sparc_stackf __user *childstack;
361 struct sparc_stackf __user *parentstack;
362
363 /*
364 * This is a clone() call with supplied user stack.
365 * Set some valid stack frames to give to the child.
366 */
367 childstack = (struct sparc_stackf __user *)
368 (sp & ~0xfUL);
369 parentstack = (struct sparc_stackf __user *)
370 regs->u_regs[UREG_FP];
371
372#if 0
373 printk("clone: parent stack:\n");
374 show_stackframe(parentstack);
375#endif
376
377 childstack = clone_stackframe(childstack, parentstack);
378 if (!childstack)
379 return -EFAULT;
380
381#if 0
382 printk("clone: child stack:\n");
383 show_stackframe(childstack);
384#endif
385
386 childregs->u_regs[UREG_FP] = (unsigned long)childstack;
387 }
388
389#ifdef CONFIG_SMP
390 /* FPU must be disabled on SMP. */
391 childregs->psr &= ~PSR_EF;
392 clear_tsk_thread_flag(p, TIF_USEDFPU);
393#endif
394
395 /* Set the return value for the child. */
396 childregs->u_regs[UREG_I0] = current->pid;
397 childregs->u_regs[UREG_I1] = 1;
398
399 /* Set the return value for the parent. */
400 regs->u_regs[UREG_I1] = 0;
401
402 if (clone_flags & CLONE_SETTLS)
403 childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
404
405 return 0;
406}
407
408/*
409 * fill in the fpu structure for a core dump.
410 */
411int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
412{
413 if (used_math()) {
414 memset(fpregs, 0, sizeof(*fpregs));
415 fpregs->pr_q_entrysize = 8;
416 return 1;
417 }
418#ifdef CONFIG_SMP
419 if (test_thread_flag(TIF_USEDFPU)) {
420 put_psr(get_psr() | PSR_EF);
421 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
422 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
423 if (regs != NULL) {
424 regs->psr &= ~(PSR_EF);
425 clear_thread_flag(TIF_USEDFPU);
426 }
427 }
428#else
429 if (current == last_task_used_math) {
430 put_psr(get_psr() | PSR_EF);
431 fpsave(¤t->thread.float_regs[0], ¤t->thread.fsr,
432 ¤t->thread.fpqueue[0], ¤t->thread.fpqdepth);
433 if (regs != NULL) {
434 regs->psr &= ~(PSR_EF);
435 last_task_used_math = NULL;
436 }
437 }
438#endif
439 memcpy(&fpregs->pr_fr.pr_regs[0],
440 ¤t->thread.float_regs[0],
441 (sizeof(unsigned long) * 32));
442 fpregs->pr_fsr = current->thread.fsr;
443 fpregs->pr_qcnt = current->thread.fpqdepth;
444 fpregs->pr_q_entrysize = 8;
445 fpregs->pr_en = 1;
446 if(fpregs->pr_qcnt != 0) {
447 memcpy(&fpregs->pr_q[0],
448 ¤t->thread.fpqueue[0],
449 sizeof(struct fpq) * fpregs->pr_qcnt);
450 }
451 /* Zero out the rest. */
452 memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
453 sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
454 return 1;
455}
456
457unsigned long get_wchan(struct task_struct *task)
458{
459 unsigned long pc, fp, bias = 0;
460 unsigned long task_base = (unsigned long) task;
461 unsigned long ret = 0;
462 struct reg_window32 *rw;
463 int count = 0;
464
465 if (!task || task == current ||
466 task->state == TASK_RUNNING)
467 goto out;
468
469 fp = task_thread_info(task)->ksp + bias;
470 do {
471 /* Bogus frame pointer? */
472 if (fp < (task_base + sizeof(struct thread_info)) ||
473 fp >= (task_base + (2 * PAGE_SIZE)))
474 break;
475 rw = (struct reg_window32 *) fp;
476 pc = rw->ins[7];
477 if (!in_sched_functions(pc)) {
478 ret = pc;
479 goto out;
480 }
481 fp = rw->ins[6] + bias;
482 } while (++count < 16);
483
484out:
485 return ret;
486}
487