Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * arch/s390/kernel/process.c |
| 3 | * |
| 4 | * S390 version |
| 5 | * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation |
| 6 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), |
| 7 | * Hartmut Penner (hp@de.ibm.com), |
| 8 | * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), |
| 9 | * |
| 10 | * Derived from "arch/i386/kernel/process.c" |
| 11 | * Copyright (C) 1995, Linus Torvalds |
| 12 | */ |
| 13 | |
| 14 | /* |
| 15 | * This file handles the architecture-dependent parts of process handling.. |
| 16 | */ |
| 17 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Alexey Dobriyan | 4e950f6 | 2007-07-30 02:36:13 +0400 | [diff] [blame] | 24 | #include <linux/fs.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <linux/smp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Heiko Carstens | 5c69971 | 2008-01-26 14:11:01 +0100 | [diff] [blame] | 38 | #include <linux/utsname.h> |
Heiko Carstens | 5a62b19 | 2008-04-17 07:46:25 +0200 | [diff] [blame] | 39 | #include <linux/tick.h> |
Heiko Carstens | a806170 | 2008-04-17 07:46:26 +0200 | [diff] [blame] | 40 | #include <linux/elfcore.h> |
Martin Schwidefsky | 6f43092 | 2008-12-31 15:11:40 +0100 | [diff] [blame] | 41 | #include <linux/kernel_stat.h> |
Heiko Carstens | 2668945 | 2009-01-14 14:14:36 +0100 | [diff] [blame^] | 42 | #include <linux/syscalls.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <asm/uaccess.h> |
| 44 | #include <asm/pgtable.h> |
| 45 | #include <asm/system.h> |
| 46 | #include <asm/io.h> |
| 47 | #include <asm/processor.h> |
| 48 | #include <asm/irq.h> |
| 49 | #include <asm/timer.h> |
Heiko Carstens | a806170 | 2008-04-17 07:46:26 +0200 | [diff] [blame] | 50 | #include "entry.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 52 | asmlinkage void ret_from_fork(void) asm ("ret_from_fork"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | |
| 54 | /* |
| 55 | * Return saved PC of a blocked thread. used in kernel/sched. |
| 56 | * resume in entry.S does not create a new stack frame, it |
| 57 | * just stores the registers %r6-%r15 to the frame given by |
| 58 | * schedule. We want to return the address of the caller of |
| 59 | * schedule, so we have to walk the backchain one time to |
| 60 | * find the frame schedule() store its return address. |
| 61 | */ |
| 62 | unsigned long thread_saved_pc(struct task_struct *tsk) |
| 63 | { |
Heiko Carstens | eb33c19 | 2006-01-14 13:20:57 -0800 | [diff] [blame] | 64 | struct stack_frame *sf, *low, *high; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | |
Heiko Carstens | eb33c19 | 2006-01-14 13:20:57 -0800 | [diff] [blame] | 66 | if (!tsk || !task_stack_page(tsk)) |
| 67 | return 0; |
| 68 | low = task_stack_page(tsk); |
| 69 | high = (struct stack_frame *) task_pt_regs(tsk); |
| 70 | sf = (struct stack_frame *) (tsk->thread.ksp & PSW_ADDR_INSN); |
| 71 | if (sf <= low || sf > high) |
| 72 | return 0; |
| 73 | sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN); |
| 74 | if (sf <= low || sf > high) |
| 75 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | return sf->gprs[8]; |
| 77 | } |
| 78 | |
Heiko Carstens | 77fa224 | 2005-06-25 14:55:30 -0700 | [diff] [blame] | 79 | extern void s390_handle_mcck(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | /* |
| 81 | * The idle loop on a S390... |
| 82 | */ |
Adrian Bunk | cdb0452 | 2006-03-24 03:15:57 -0800 | [diff] [blame] | 83 | static void default_idle(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | /* CPU is going idle. */ |
Nick Piggin | 64c7c8f | 2005-11-08 21:39:04 -0800 | [diff] [blame] | 86 | local_irq_disable(); |
| 87 | if (need_resched()) { |
| 88 | local_irq_enable(); |
| 89 | return; |
| 90 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | #ifdef CONFIG_HOTPLUG_CPU |
Heiko Carstens | 43ca5c3 | 2008-04-17 07:46:23 +0200 | [diff] [blame] | 92 | if (cpu_is_offline(smp_processor_id())) { |
Heiko Carstens | 1fca251 | 2006-02-17 13:52:46 -0800 | [diff] [blame] | 93 | preempt_enable_no_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | cpu_die(); |
Heiko Carstens | 1fca251 | 2006-02-17 13:52:46 -0800 | [diff] [blame] | 95 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | #endif |
Heiko Carstens | 77fa224 | 2005-06-25 14:55:30 -0700 | [diff] [blame] | 97 | local_mcck_disable(); |
| 98 | if (test_thread_flag(TIF_MCCK_PENDING)) { |
| 99 | local_mcck_enable(); |
| 100 | local_irq_enable(); |
| 101 | s390_handle_mcck(); |
| 102 | return; |
| 103 | } |
Heiko Carstens | 1f194a4 | 2006-07-03 00:24:46 -0700 | [diff] [blame] | 104 | trace_hardirqs_on(); |
Heiko Carstens | 632448f | 2008-11-14 18:18:04 +0100 | [diff] [blame] | 105 | /* Don't trace preempt off for idle. */ |
| 106 | stop_critical_timings(); |
Martin Schwidefsky | 9cfb9b3 | 2008-12-31 15:11:41 +0100 | [diff] [blame] | 107 | /* Stop virtual timer and halt the cpu. */ |
| 108 | vtime_stop_cpu(); |
| 109 | /* Reenable preemption tracer. */ |
Heiko Carstens | 632448f | 2008-11-14 18:18:04 +0100 | [diff] [blame] | 110 | start_critical_timings(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | void cpu_idle(void) |
| 114 | { |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 115 | for (;;) { |
Thomas Gleixner | e338125 | 2008-07-19 09:33:21 +0200 | [diff] [blame] | 116 | tick_nohz_stop_sched_tick(1); |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 117 | while (!need_resched()) |
| 118 | default_idle(); |
Heiko Carstens | 5a62b19 | 2008-04-17 07:46:25 +0200 | [diff] [blame] | 119 | tick_nohz_restart_sched_tick(); |
Nick Piggin | 5bfb5d6 | 2005-11-08 21:39:01 -0800 | [diff] [blame] | 120 | preempt_enable_no_resched(); |
| 121 | schedule(); |
| 122 | preempt_disable(); |
| 123 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | } |
| 125 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | extern void kernel_thread_starter(void); |
| 127 | |
Martin Schwidefsky | 94c12cc | 2006-09-28 16:56:43 +0200 | [diff] [blame] | 128 | asm( |
| 129 | ".align 4\n" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | "kernel_thread_starter:\n" |
| 131 | " la 2,0(10)\n" |
| 132 | " basr 14,9\n" |
| 133 | " la 2,0\n" |
| 134 | " br 11\n"); |
| 135 | |
| 136 | int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) |
| 137 | { |
| 138 | struct pt_regs regs; |
| 139 | |
| 140 | memset(®s, 0, sizeof(regs)); |
Gerald Schaefer | c1821c2 | 2007-02-05 21:18:17 +0100 | [diff] [blame] | 141 | regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE; |
| 143 | regs.gprs[9] = (unsigned long) fn; |
| 144 | regs.gprs[10] = (unsigned long) arg; |
| 145 | regs.gprs[11] = (unsigned long) do_exit; |
| 146 | regs.orig_gpr2 = -1; |
| 147 | |
| 148 | /* Ok, create the new process.. */ |
| 149 | return do_fork(flags | CLONE_VM | CLONE_UNTRACED, |
| 150 | 0, ®s, 0, NULL, NULL); |
| 151 | } |
| 152 | |
| 153 | /* |
| 154 | * Free current thread data structures etc.. |
| 155 | */ |
| 156 | void exit_thread(void) |
| 157 | { |
| 158 | } |
| 159 | |
| 160 | void flush_thread(void) |
| 161 | { |
| 162 | clear_used_math(); |
| 163 | clear_tsk_thread_flag(current, TIF_USEDFPU); |
| 164 | } |
| 165 | |
| 166 | void release_thread(struct task_struct *dead_task) |
| 167 | { |
| 168 | } |
| 169 | |
| 170 | int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp, |
| 171 | unsigned long unused, |
| 172 | struct task_struct * p, struct pt_regs * regs) |
| 173 | { |
| 174 | struct fake_frame |
| 175 | { |
| 176 | struct stack_frame sf; |
| 177 | struct pt_regs childregs; |
| 178 | } *frame; |
| 179 | |
Al Viro | c7584fb | 2006-01-12 01:05:49 -0800 | [diff] [blame] | 180 | frame = container_of(task_pt_regs(p), struct fake_frame, childregs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | p->thread.ksp = (unsigned long) frame; |
| 182 | /* Store access registers to kernel stack of new process. */ |
| 183 | frame->childregs = *regs; |
| 184 | frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */ |
| 185 | frame->childregs.gprs[15] = new_stackp; |
| 186 | frame->sf.back_chain = 0; |
| 187 | |
| 188 | /* new return point is ret_from_fork */ |
| 189 | frame->sf.gprs[8] = (unsigned long) ret_from_fork; |
| 190 | |
| 191 | /* fake return stack for resume(), don't go back to schedule */ |
| 192 | frame->sf.gprs[9] = (unsigned long) frame; |
| 193 | |
| 194 | /* Save access registers to new thread structure. */ |
| 195 | save_access_regs(&p->thread.acrs[0]); |
| 196 | |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 197 | #ifndef CONFIG_64BIT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | /* |
| 199 | * save fprs to current->thread.fp_regs to merge them with |
| 200 | * the emulated registers and then copy the result to the child. |
| 201 | */ |
| 202 | save_fp_regs(¤t->thread.fp_regs); |
| 203 | memcpy(&p->thread.fp_regs, ¤t->thread.fp_regs, |
| 204 | sizeof(s390_fp_regs)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | /* Set a new TLS ? */ |
| 206 | if (clone_flags & CLONE_SETTLS) |
| 207 | p->thread.acrs[0] = regs->gprs[6]; |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 208 | #else /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | /* Save the fpu registers to new thread structure. */ |
| 210 | save_fp_regs(&p->thread.fp_regs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 211 | /* Set a new TLS ? */ |
| 212 | if (clone_flags & CLONE_SETTLS) { |
| 213 | if (test_thread_flag(TIF_31BIT)) { |
| 214 | p->thread.acrs[0] = (unsigned int) regs->gprs[6]; |
| 215 | } else { |
| 216 | p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32); |
| 217 | p->thread.acrs[1] = (unsigned int) regs->gprs[6]; |
| 218 | } |
| 219 | } |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 220 | #endif /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | /* start new process with ar4 pointing to the correct address space */ |
| 222 | p->thread.mm_segment = get_fs(); |
| 223 | /* Don't copy debug registers */ |
| 224 | memset(&p->thread.per_info,0,sizeof(p->thread.per_info)); |
| 225 | |
| 226 | return 0; |
| 227 | } |
| 228 | |
Heiko Carstens | 2668945 | 2009-01-14 14:14:36 +0100 | [diff] [blame^] | 229 | SYSCALL_DEFINE0(fork) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | { |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 231 | struct pt_regs *regs = task_pt_regs(current); |
| 232 | return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | } |
| 234 | |
Heiko Carstens | 2668945 | 2009-01-14 14:14:36 +0100 | [diff] [blame^] | 235 | SYSCALL_DEFINE0(clone) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | { |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 237 | struct pt_regs *regs = task_pt_regs(current); |
| 238 | unsigned long clone_flags; |
| 239 | unsigned long newsp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | int __user *parent_tidptr, *child_tidptr; |
| 241 | |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 242 | clone_flags = regs->gprs[3]; |
| 243 | newsp = regs->orig_gpr2; |
| 244 | parent_tidptr = (int __user *) regs->gprs[4]; |
| 245 | child_tidptr = (int __user *) regs->gprs[5]; |
| 246 | if (!newsp) |
| 247 | newsp = regs->gprs[15]; |
| 248 | return do_fork(clone_flags, newsp, regs, 0, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | parent_tidptr, child_tidptr); |
| 250 | } |
| 251 | |
| 252 | /* |
| 253 | * This is trivial, and on the face of it looks like it |
| 254 | * could equally well be done in user mode. |
| 255 | * |
| 256 | * Not so, for quite unobvious reasons - register pressure. |
| 257 | * In user mode vfork() cannot have a stack frame, and if |
| 258 | * done by calling the "clone()" system call directly, you |
| 259 | * do not have enough call-clobbered registers to hold all |
| 260 | * the information you need. |
| 261 | */ |
Heiko Carstens | 2668945 | 2009-01-14 14:14:36 +0100 | [diff] [blame^] | 262 | SYSCALL_DEFINE0(vfork) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | { |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 264 | struct pt_regs *regs = task_pt_regs(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 266 | regs->gprs[15], regs, 0, NULL, NULL); |
| 267 | } |
| 268 | |
| 269 | asmlinkage void execve_tail(void) |
| 270 | { |
| 271 | task_lock(current); |
| 272 | current->ptrace &= ~PT_DTRACE; |
| 273 | task_unlock(current); |
| 274 | current->thread.fp_regs.fpc = 0; |
| 275 | if (MACHINE_HAS_IEEE) |
| 276 | asm volatile("sfpc %0,%0" : : "d" (0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | } |
| 278 | |
| 279 | /* |
| 280 | * sys_execve() executes a new program. |
| 281 | */ |
Heiko Carstens | 2668945 | 2009-01-14 14:14:36 +0100 | [diff] [blame^] | 282 | SYSCALL_DEFINE0(execve) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | { |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 284 | struct pt_regs *regs = task_pt_regs(current); |
| 285 | char *filename; |
| 286 | unsigned long result; |
| 287 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 289 | filename = getname((char __user *) regs->orig_gpr2); |
| 290 | if (IS_ERR(filename)) { |
| 291 | result = PTR_ERR(filename); |
| 292 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | } |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 294 | rc = do_execve(filename, (char __user * __user *) regs->gprs[3], |
| 295 | (char __user * __user *) regs->gprs[4], regs); |
| 296 | if (rc) { |
| 297 | result = rc; |
| 298 | goto out_putname; |
| 299 | } |
| 300 | execve_tail(); |
| 301 | result = regs->gprs[2]; |
| 302 | out_putname: |
| 303 | putname(filename); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | out: |
Martin Schwidefsky | 03ff9a2 | 2007-04-27 16:01:40 +0200 | [diff] [blame] | 305 | return result; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | } |
| 307 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 308 | /* |
| 309 | * fill in the FPU structure for a core dump. |
| 310 | */ |
| 311 | int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs) |
| 312 | { |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 313 | #ifndef CONFIG_64BIT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | /* |
| 315 | * save fprs to current->thread.fp_regs to merge them with |
| 316 | * the emulated registers and then copy the result to the dump. |
| 317 | */ |
| 318 | save_fp_regs(¤t->thread.fp_regs); |
| 319 | memcpy(fpregs, ¤t->thread.fp_regs, sizeof(s390_fp_regs)); |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 320 | #else /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | save_fp_regs(fpregs); |
Martin Schwidefsky | 347a8dc | 2006-01-06 00:19:28 -0800 | [diff] [blame] | 322 | #endif /* CONFIG_64BIT */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | return 1; |
| 324 | } |
| 325 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | unsigned long get_wchan(struct task_struct *p) |
| 327 | { |
| 328 | struct stack_frame *sf, *low, *high; |
| 329 | unsigned long return_address; |
| 330 | int count; |
| 331 | |
Al Viro | 30af712 | 2006-01-12 01:05:50 -0800 | [diff] [blame] | 332 | if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | return 0; |
Al Viro | 30af712 | 2006-01-12 01:05:50 -0800 | [diff] [blame] | 334 | low = task_stack_page(p); |
| 335 | high = (struct stack_frame *) task_pt_regs(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN); |
| 337 | if (sf <= low || sf > high) |
| 338 | return 0; |
| 339 | for (count = 0; count < 16; count++) { |
| 340 | sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN); |
| 341 | if (sf <= low || sf > high) |
| 342 | return 0; |
| 343 | return_address = sf->gprs[8] & PSW_ADDR_INSN; |
| 344 | if (!in_sched_functions(return_address)) |
| 345 | return return_address; |
| 346 | } |
| 347 | return 0; |
| 348 | } |
| 349 | |