1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18#include <linux/compiler.h>
19#include <linux/cpu.h>
20#include <linux/errno.h>
21#include <linux/sched.h>
22#include <linux/kernel.h>
23#include <linux/mm.h>
24#include <linux/fs.h>
25#include <linux/smp.h>
26#include <linux/stddef.h>
27#include <linux/unistd.h>
28#include <linux/ptrace.h>
29#include <linux/slab.h>
30#include <linux/vmalloc.h>
31#include <linux/user.h>
32#include <linux/interrupt.h>
33#include <linux/delay.h>
34#include <linux/reboot.h>
35#include <linux/init.h>
36#include <linux/module.h>
37#include <linux/notifier.h>
38#include <linux/utsname.h>
39#include <linux/tick.h>
40#include <linux/elfcore.h>
41#include <asm/uaccess.h>
42#include <asm/pgtable.h>
43#include <asm/system.h>
44#include <asm/io.h>
45#include <asm/processor.h>
46#include <asm/irq.h>
47#include <asm/timer.h>
48#include <asm/cpu.h>
49#include "entry.h"
50
51asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
52
53
54
55
56
57
58
59
60
61unsigned long thread_saved_pc(struct task_struct *tsk)
62{
63 struct stack_frame *sf, *low, *high;
64
65 if (!tsk || !task_stack_page(tsk))
66 return 0;
67 low = task_stack_page(tsk);
68 high = (struct stack_frame *) task_pt_regs(tsk);
69 sf = (struct stack_frame *) (tsk->thread.ksp & PSW_ADDR_INSN);
70 if (sf <= low || sf > high)
71 return 0;
72 sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
73 if (sf <= low || sf > high)
74 return 0;
75 return sf->gprs[8];
76}
77
78DEFINE_PER_CPU(struct s390_idle_data, s390_idle) = {
79 .lock = __SPIN_LOCK_UNLOCKED(s390_idle.lock)
80};
81
82static int s390_idle_enter(void)
83{
84 struct s390_idle_data *idle;
85
86 idle = &__get_cpu_var(s390_idle);
87 spin_lock(&idle->lock);
88 idle->idle_count++;
89 idle->in_idle = 1;
90 idle->idle_enter = get_clock();
91 spin_unlock(&idle->lock);
92 vtime_stop_cpu_timer();
93 return NOTIFY_OK;
94}
95
96void s390_idle_leave(void)
97{
98 struct s390_idle_data *idle;
99
100 vtime_start_cpu_timer();
101 idle = &__get_cpu_var(s390_idle);
102 spin_lock(&idle->lock);
103 idle->idle_time += get_clock() - idle->idle_enter;
104 idle->in_idle = 0;
105 spin_unlock(&idle->lock);
106}
107
108extern void s390_handle_mcck(void);
109
110
111
112static void default_idle(void)
113{
114
115 local_irq_disable();
116 if (need_resched()) {
117 local_irq_enable();
118 return;
119 }
120 if (s390_idle_enter() == NOTIFY_BAD) {
121 local_irq_enable();
122 return;
123 }
124#ifdef CONFIG_HOTPLUG_CPU
125 if (cpu_is_offline(smp_processor_id())) {
126 preempt_enable_no_resched();
127 cpu_die();
128 }
129#endif
130 local_mcck_disable();
131 if (test_thread_flag(TIF_MCCK_PENDING)) {
132 local_mcck_enable();
133 s390_idle_leave();
134 local_irq_enable();
135 s390_handle_mcck();
136 return;
137 }
138 trace_hardirqs_on();
139
140 stop_critical_timings();
141
142 __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT |
143 PSW_MASK_IO | PSW_MASK_EXT);
144 start_critical_timings();
145}
146
147void cpu_idle(void)
148{
149 for (;;) {
150 tick_nohz_stop_sched_tick(1);
151 while (!need_resched())
152 default_idle();
153 tick_nohz_restart_sched_tick();
154 preempt_enable_no_resched();
155 schedule();
156 preempt_disable();
157 }
158}
159
160extern void kernel_thread_starter(void);
161
162asm(
163 ".align 4\n"
164 "kernel_thread_starter:\n"
165 " la 2,0(10)\n"
166 " basr 14,9\n"
167 " la 2,0\n"
168 " br 11\n");
169
170int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
171{
172 struct pt_regs regs;
173
174 memset(®s, 0, sizeof(regs));
175 regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
176 regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
177 regs.gprs[9] = (unsigned long) fn;
178 regs.gprs[10] = (unsigned long) arg;
179 regs.gprs[11] = (unsigned long) do_exit;
180 regs.orig_gpr2 = -1;
181
182
183 return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
184 0, ®s, 0, NULL, NULL);
185}
186
187
188
189
190void exit_thread(void)
191{
192}
193
194void flush_thread(void)
195{
196 clear_used_math();
197 clear_tsk_thread_flag(current, TIF_USEDFPU);
198}
199
200void release_thread(struct task_struct *dead_task)
201{
202}
203
204int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,
205 unsigned long unused,
206 struct task_struct * p, struct pt_regs * regs)
207{
208 struct fake_frame
209 {
210 struct stack_frame sf;
211 struct pt_regs childregs;
212 } *frame;
213
214 frame = container_of(task_pt_regs(p), struct fake_frame, childregs);
215 p->thread.ksp = (unsigned long) frame;
216
217 frame->childregs = *regs;
218 frame->childregs.gprs[2] = 0;
219 frame->childregs.gprs[15] = new_stackp;
220 frame->sf.back_chain = 0;
221
222
223 frame->sf.gprs[8] = (unsigned long) ret_from_fork;
224
225
226 frame->sf.gprs[9] = (unsigned long) frame;
227
228
229 save_access_regs(&p->thread.acrs[0]);
230
231#ifndef CONFIG_64BIT
232
233
234
235
236 save_fp_regs(¤t->thread.fp_regs);
237 memcpy(&p->thread.fp_regs, ¤t->thread.fp_regs,
238 sizeof(s390_fp_regs));
239
240 if (clone_flags & CLONE_SETTLS)
241 p->thread.acrs[0] = regs->gprs[6];
242#else
243
244 save_fp_regs(&p->thread.fp_regs);
245
246 if (clone_flags & CLONE_SETTLS) {
247 if (test_thread_flag(TIF_31BIT)) {
248 p->thread.acrs[0] = (unsigned int) regs->gprs[6];
249 } else {
250 p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
251 p->thread.acrs[1] = (unsigned int) regs->gprs[6];
252 }
253 }
254#endif
255
256 p->thread.mm_segment = get_fs();
257
258 memset(&p->thread.per_info,0,sizeof(p->thread.per_info));
259
260 return 0;
261}
262
263asmlinkage long sys_fork(void)
264{
265 struct pt_regs *regs = task_pt_regs(current);
266 return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL);
267}
268
269asmlinkage long sys_clone(void)
270{
271 struct pt_regs *regs = task_pt_regs(current);
272 unsigned long clone_flags;
273 unsigned long newsp;
274 int __user *parent_tidptr, *child_tidptr;
275
276 clone_flags = regs->gprs[3];
277 newsp = regs->orig_gpr2;
278 parent_tidptr = (int __user *) regs->gprs[4];
279 child_tidptr = (int __user *) regs->gprs[5];
280 if (!newsp)
281 newsp = regs->gprs[15];
282 return do_fork(clone_flags, newsp, regs, 0,
283 parent_tidptr, child_tidptr);
284}
285
286
287
288
289
290
291
292
293
294
295
296asmlinkage long sys_vfork(void)
297{
298 struct pt_regs *regs = task_pt_regs(current);
299 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
300 regs->gprs[15], regs, 0, NULL, NULL);
301}
302
303asmlinkage void execve_tail(void)
304{
305 task_lock(current);
306 current->ptrace &= ~PT_DTRACE;
307 task_unlock(current);
308 current->thread.fp_regs.fpc = 0;
309 if (MACHINE_HAS_IEEE)
310 asm volatile("sfpc %0,%0" : : "d" (0));
311}
312
313
314
315
316asmlinkage long sys_execve(void)
317{
318 struct pt_regs *regs = task_pt_regs(current);
319 char *filename;
320 unsigned long result;
321 int rc;
322
323 filename = getname((char __user *) regs->orig_gpr2);
324 if (IS_ERR(filename)) {
325 result = PTR_ERR(filename);
326 goto out;
327 }
328 rc = do_execve(filename, (char __user * __user *) regs->gprs[3],
329 (char __user * __user *) regs->gprs[4], regs);
330 if (rc) {
331 result = rc;
332 goto out_putname;
333 }
334 execve_tail();
335 result = regs->gprs[2];
336out_putname:
337 putname(filename);
338out:
339 return result;
340}
341
342
343
344
345int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
346{
347#ifndef CONFIG_64BIT
348
349
350
351
352 save_fp_regs(¤t->thread.fp_regs);
353 memcpy(fpregs, ¤t->thread.fp_regs, sizeof(s390_fp_regs));
354#else
355 save_fp_regs(fpregs);
356#endif
357 return 1;
358}
359
360unsigned long get_wchan(struct task_struct *p)
361{
362 struct stack_frame *sf, *low, *high;
363 unsigned long return_address;
364 int count;
365
366 if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p))
367 return 0;
368 low = task_stack_page(p);
369 high = (struct stack_frame *) task_pt_regs(p);
370 sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);
371 if (sf <= low || sf > high)
372 return 0;
373 for (count = 0; count < 16; count++) {
374 sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
375 if (sf <= low || sf > high)
376 return 0;
377 return_address = sf->gprs[8] & PSW_ADDR_INSN;
378 if (!in_sched_functions(return_address))
379 return return_address;
380 }
381 return 0;
382}
383
384