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10#include <linux/compiler.h>
11#include <linux/cpu.h>
12#include <linux/errno.h>
13#include <linux/sched.h>
14#include <linux/kernel.h>
15#include <linux/mm.h>
16#include <linux/fs.h>
17#include <linux/smp.h>
18#include <linux/stddef.h>
19#include <linux/slab.h>
20#include <linux/unistd.h>
21#include <linux/ptrace.h>
22#include <linux/vmalloc.h>
23#include <linux/user.h>
24#include <linux/interrupt.h>
25#include <linux/delay.h>
26#include <linux/reboot.h>
27#include <linux/init.h>
28#include <linux/module.h>
29#include <linux/notifier.h>
30#include <linux/tick.h>
31#include <linux/elfcore.h>
32#include <linux/kernel_stat.h>
33#include <linux/personality.h>
34#include <linux/syscalls.h>
35#include <linux/compat.h>
36#include <linux/kprobes.h>
37#include <linux/random.h>
38#include <asm/compat.h>
39#include <asm/uaccess.h>
40#include <asm/pgtable.h>
41#include <asm/system.h>
42#include <asm/io.h>
43#include <asm/processor.h>
44#include <asm/irq.h>
45#include <asm/timer.h>
46#include <asm/nmi.h>
47#include <asm/smp.h>
48#include "entry.h"
49
50asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
51
52
53
54
55
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57
58
59
60unsigned long thread_saved_pc(struct task_struct *tsk)
61{
62 struct stack_frame *sf, *low, *high;
63
64 if (!tsk || !task_stack_page(tsk))
65 return 0;
66 low = task_stack_page(tsk);
67 high = (struct stack_frame *) task_pt_regs(tsk);
68 sf = (struct stack_frame *) (tsk->thread.ksp & PSW_ADDR_INSN);
69 if (sf <= low || sf > high)
70 return 0;
71 sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
72 if (sf <= low || sf > high)
73 return 0;
74 return sf->gprs[8];
75}
76
77
78
79
80static void default_idle(void)
81{
82 if (cpu_is_offline(smp_processor_id()))
83 cpu_die();
84 local_irq_disable();
85 if (need_resched()) {
86 local_irq_enable();
87 return;
88 }
89 local_mcck_disable();
90 if (test_thread_flag(TIF_MCCK_PENDING)) {
91 local_mcck_enable();
92 local_irq_enable();
93 s390_handle_mcck();
94 return;
95 }
96 trace_hardirqs_on();
97
98 stop_critical_timings();
99
100 vtime_stop_cpu();
101
102 start_critical_timings();
103}
104
105void cpu_idle(void)
106{
107 for (;;) {
108 tick_nohz_stop_sched_tick(1);
109 while (!need_resched())
110 default_idle();
111 tick_nohz_restart_sched_tick();
112 preempt_enable_no_resched();
113 schedule();
114 preempt_disable();
115 }
116}
117
118extern void __kprobes kernel_thread_starter(void);
119
120asm(
121 ".section .kprobes.text, \"ax\"\n"
122 ".global kernel_thread_starter\n"
123 "kernel_thread_starter:\n"
124 " la 2,0(10)\n"
125 " basr 14,9\n"
126 " la 2,0\n"
127 " br 11\n"
128 ".previous\n");
129
130int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
131{
132 struct pt_regs regs;
133
134 memset(®s, 0, sizeof(regs));
135 regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
136 regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
137 regs.gprs[9] = (unsigned long) fn;
138 regs.gprs[10] = (unsigned long) arg;
139 regs.gprs[11] = (unsigned long) do_exit;
140 regs.orig_gpr2 = -1;
141
142
143 return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
144 0, ®s, 0, NULL, NULL);
145}
146EXPORT_SYMBOL(kernel_thread);
147
148
149
150
151void exit_thread(void)
152{
153}
154
155void flush_thread(void)
156{
157}
158
159void release_thread(struct task_struct *dead_task)
160{
161}
162
163int copy_thread(unsigned long clone_flags, unsigned long new_stackp,
164 unsigned long unused,
165 struct task_struct *p, struct pt_regs *regs)
166{
167 struct thread_info *ti;
168 struct fake_frame
169 {
170 struct stack_frame sf;
171 struct pt_regs childregs;
172 } *frame;
173
174 frame = container_of(task_pt_regs(p), struct fake_frame, childregs);
175 p->thread.ksp = (unsigned long) frame;
176
177 frame->childregs = *regs;
178 frame->childregs.gprs[2] = 0;
179 frame->childregs.gprs[15] = new_stackp;
180 frame->sf.back_chain = 0;
181
182
183 frame->sf.gprs[8] = (unsigned long) ret_from_fork;
184
185
186 frame->sf.gprs[9] = (unsigned long) frame;
187
188
189 save_access_regs(&p->thread.acrs[0]);
190
191#ifndef CONFIG_64BIT
192
193
194
195
196 save_fp_regs(¤t->thread.fp_regs);
197 memcpy(&p->thread.fp_regs, ¤t->thread.fp_regs,
198 sizeof(s390_fp_regs));
199
200 if (clone_flags & CLONE_SETTLS)
201 p->thread.acrs[0] = regs->gprs[6];
202#else
203
204 save_fp_regs(&p->thread.fp_regs);
205
206 if (clone_flags & CLONE_SETTLS) {
207 if (is_compat_task()) {
208 p->thread.acrs[0] = (unsigned int) regs->gprs[6];
209 } else {
210 p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
211 p->thread.acrs[1] = (unsigned int) regs->gprs[6];
212 }
213 }
214#endif
215
216 p->thread.mm_segment = get_fs();
217
218 memset(&p->thread.per_user, 0, sizeof(p->thread.per_user));
219 memset(&p->thread.per_event, 0, sizeof(p->thread.per_event));
220 clear_tsk_thread_flag(p, TIF_SINGLE_STEP);
221 clear_tsk_thread_flag(p, TIF_PER_TRAP);
222
223 ti = task_thread_info(p);
224 ti->user_timer = 0;
225 ti->system_timer = 0;
226 return 0;
227}
228
229SYSCALL_DEFINE0(fork)
230{
231 struct pt_regs *regs = task_pt_regs(current);
232 return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL);
233}
234
235SYSCALL_DEFINE4(clone, unsigned long, newsp, unsigned long, clone_flags,
236 int __user *, parent_tidptr, int __user *, child_tidptr)
237{
238 struct pt_regs *regs = task_pt_regs(current);
239
240 if (!newsp)
241 newsp = regs->gprs[15];
242 return do_fork(clone_flags, newsp, regs, 0,
243 parent_tidptr, child_tidptr);
244}
245
246
247
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249
250
251
252
253
254
255
256SYSCALL_DEFINE0(vfork)
257{
258 struct pt_regs *regs = task_pt_regs(current);
259 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
260 regs->gprs[15], regs, 0, NULL, NULL);
261}
262
263asmlinkage void execve_tail(void)
264{
265 current->thread.fp_regs.fpc = 0;
266 if (MACHINE_HAS_IEEE)
267 asm volatile("sfpc %0,%0" : : "d" (0));
268}
269
270
271
272
273SYSCALL_DEFINE3(execve, const char __user *, name,
274 const char __user *const __user *, argv,
275 const char __user *const __user *, envp)
276{
277 struct pt_regs *regs = task_pt_regs(current);
278 char *filename;
279 long rc;
280
281 filename = getname(name);
282 rc = PTR_ERR(filename);
283 if (IS_ERR(filename))
284 return rc;
285 rc = do_execve(filename, argv, envp, regs);
286 if (rc)
287 goto out;
288 execve_tail();
289 rc = regs->gprs[2];
290out:
291 putname(filename);
292 return rc;
293}
294
295
296
297
298int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
299{
300#ifndef CONFIG_64BIT
301
302
303
304
305 save_fp_regs(¤t->thread.fp_regs);
306 memcpy(fpregs, ¤t->thread.fp_regs, sizeof(s390_fp_regs));
307#else
308 save_fp_regs(fpregs);
309#endif
310 return 1;
311}
312EXPORT_SYMBOL(dump_fpu);
313
314unsigned long get_wchan(struct task_struct *p)
315{
316 struct stack_frame *sf, *low, *high;
317 unsigned long return_address;
318 int count;
319
320 if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p))
321 return 0;
322 low = task_stack_page(p);
323 high = (struct stack_frame *) task_pt_regs(p);
324 sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);
325 if (sf <= low || sf > high)
326 return 0;
327 for (count = 0; count < 16; count++) {
328 sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
329 if (sf <= low || sf > high)
330 return 0;
331 return_address = sf->gprs[8] & PSW_ADDR_INSN;
332 if (!in_sched_functions(return_address))
333 return return_address;
334 }
335 return 0;
336}
337
338unsigned long arch_align_stack(unsigned long sp)
339{
340 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
341 sp -= get_random_int() & ~PAGE_MASK;
342 return sp & ~0xf;
343}
344
345static inline unsigned long brk_rnd(void)
346{
347
348 if (is_32bit_task())
349 return (get_random_int() & 0x7ffUL) << PAGE_SHIFT;
350 else
351 return (get_random_int() & 0x3ffffUL) << PAGE_SHIFT;
352}
353
354unsigned long arch_randomize_brk(struct mm_struct *mm)
355{
356 unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
357
358 if (ret < mm->brk)
359 return mm->brk;
360 return ret;
361}
362
363unsigned long randomize_et_dyn(unsigned long base)
364{
365 unsigned long ret = PAGE_ALIGN(base + brk_rnd());
366
367 if (!(current->flags & PF_RANDOMIZE))
368 return base;
369 if (ret < base)
370 return base;
371 return ret;
372}
373