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[/] [test_project/] [trunk/] [linux_sd_driver/] [arch/] [s390/] [kernel/] [process.c] - Blame information for rev 63

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/*
 *  arch/s390/kernel/process.c
 *
 *  S390 version
 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *               Hartmut Penner (hp@de.ibm.com),
 *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
 *
 *  Derived from "arch/i386/kernel/process.c"
 *    Copyright (C) 1995, Linus Torvalds
 */
 
/*
 * This file handles the architecture-dependent parts of process handling..
 */
 
#include <linux/compiler.h>
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/notifier.h>
 
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/irq.h>
#include <asm/timer.h>
#include <asm/cpu.h>
 
asmlinkage void ret_from_fork(void) asm ("ret_from_fork");
 
/*
 * Return saved PC of a blocked thread. used in kernel/sched.
 * resume in entry.S does not create a new stack frame, it
 * just stores the registers %r6-%r15 to the frame given by
 * schedule. We want to return the address of the caller of
 * schedule, so we have to walk the backchain one time to
 * find the frame schedule() store its return address.
 */
unsigned long thread_saved_pc(struct task_struct *tsk)
{
        struct stack_frame *sf, *low, *high;
 
        if (!tsk || !task_stack_page(tsk))
                return 0;
        low = task_stack_page(tsk);
        high = (struct stack_frame *) task_pt_regs(tsk);
        sf = (struct stack_frame *) (tsk->thread.ksp & PSW_ADDR_INSN);
        if (sf <= low || sf > high)
                return 0;
        sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
        if (sf <= low || sf > high)
                return 0;
        return sf->gprs[8];
}
 
/*
 * Need to know about CPUs going idle?
 */
static ATOMIC_NOTIFIER_HEAD(idle_chain);
 
int register_idle_notifier(struct notifier_block *nb)
{
        return atomic_notifier_chain_register(&idle_chain, nb);
}
EXPORT_SYMBOL(register_idle_notifier);
 
int unregister_idle_notifier(struct notifier_block *nb)
{
        return atomic_notifier_chain_unregister(&idle_chain, nb);
}
EXPORT_SYMBOL(unregister_idle_notifier);
 
void do_monitor_call(struct pt_regs *regs, long interruption_code)
{
#ifdef CONFIG_SMP
        struct s390_idle_data *idle;
 
        idle = &__get_cpu_var(s390_idle);
        spin_lock(&idle->lock);
        idle->idle_time += get_clock() - idle->idle_enter;
        idle->in_idle = 0;
        spin_unlock(&idle->lock);
#endif
        /* disable monitor call class 0 */
        __ctl_clear_bit(8, 15);
 
        atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,
                                   (void *)(long) smp_processor_id());
}
 
extern void s390_handle_mcck(void);
/*
 * The idle loop on a S390...
 */
static void default_idle(void)
{
        int cpu, rc;
#ifdef CONFIG_SMP
        struct s390_idle_data *idle;
#endif
 
        /* CPU is going idle. */
        cpu = smp_processor_id();
 
        local_irq_disable();
        if (need_resched()) {
                local_irq_enable();
                return;
        }
 
        rc = atomic_notifier_call_chain(&idle_chain,
                                        S390_CPU_IDLE, (void *)(long) cpu);
        if (rc != NOTIFY_OK && rc != NOTIFY_DONE)
                BUG();
        if (rc != NOTIFY_OK) {
                local_irq_enable();
                return;
        }
 
        /* enable monitor call class 0 */
        __ctl_set_bit(8, 15);
 
#ifdef CONFIG_HOTPLUG_CPU
        if (cpu_is_offline(cpu)) {
                preempt_enable_no_resched();
                cpu_die();
        }
#endif
 
        local_mcck_disable();
        if (test_thread_flag(TIF_MCCK_PENDING)) {
                local_mcck_enable();
                local_irq_enable();
                s390_handle_mcck();
                return;
        }
#ifdef CONFIG_SMP
        idle = &__get_cpu_var(s390_idle);
        spin_lock(&idle->lock);
        idle->idle_count++;
        idle->in_idle = 1;
        idle->idle_enter = get_clock();
        spin_unlock(&idle->lock);
#endif
        trace_hardirqs_on();
        /* Wait for external, I/O or machine check interrupt. */
        __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT |
                        PSW_MASK_IO | PSW_MASK_EXT);
}
 
void cpu_idle(void)
{
        for (;;) {
                while (!need_resched())
                        default_idle();
 
                preempt_enable_no_resched();
                schedule();
                preempt_disable();
        }
}
 
void show_regs(struct pt_regs *regs)
{
        struct task_struct *tsk = current;
 
        printk("CPU:    %d    %s\n", task_thread_info(tsk)->cpu, print_tainted());
        printk("Process %s (pid: %d, task: %p, ksp: %p)\n",
               current->comm, task_pid_nr(current), (void *) tsk,
               (void *) tsk->thread.ksp);
 
        show_registers(regs);
        /* Show stack backtrace if pt_regs is from kernel mode */
        if (!(regs->psw.mask & PSW_MASK_PSTATE))
                show_trace(NULL, (unsigned long *) regs->gprs[15]);
}
 
extern void kernel_thread_starter(void);
 
asm(
        ".align 4\n"
        "kernel_thread_starter:\n"
        "    la    2,0(10)\n"
        "    basr  14,9\n"
        "    la    2,0\n"
        "    br    11\n");
 
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
        struct pt_regs regs;
 
        memset(&regs, 0, sizeof(regs));
        regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
        regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
        regs.gprs[9] = (unsigned long) fn;
        regs.gprs[10] = (unsigned long) arg;
        regs.gprs[11] = (unsigned long) do_exit;
        regs.orig_gpr2 = -1;
 
        /* Ok, create the new process.. */
        return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
                       0, &regs, 0, NULL, NULL);
}
 
/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
}
 
void flush_thread(void)
{
        clear_used_math();
        clear_tsk_thread_flag(current, TIF_USEDFPU);
}
 
void release_thread(struct task_struct *dead_task)
{
}
 
int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,
        unsigned long unused,
        struct task_struct * p, struct pt_regs * regs)
{
        struct fake_frame
          {
            struct stack_frame sf;
            struct pt_regs childregs;
          } *frame;
 
        frame = container_of(task_pt_regs(p), struct fake_frame, childregs);
        p->thread.ksp = (unsigned long) frame;
        /* Store access registers to kernel stack of new process. */
        frame->childregs = *regs;
        frame->childregs.gprs[2] = 0;    /* child returns 0 on fork. */
        frame->childregs.gprs[15] = new_stackp;
        frame->sf.back_chain = 0;
 
        /* new return point is ret_from_fork */
        frame->sf.gprs[8] = (unsigned long) ret_from_fork;
 
        /* fake return stack for resume(), don't go back to schedule */
        frame->sf.gprs[9] = (unsigned long) frame;
 
        /* Save access registers to new thread structure. */
        save_access_regs(&p->thread.acrs[0]);
 
#ifndef CONFIG_64BIT
        /*
         * save fprs to current->thread.fp_regs to merge them with
         * the emulated registers and then copy the result to the child.
         */
        save_fp_regs(&current->thread.fp_regs);
        memcpy(&p->thread.fp_regs, &current->thread.fp_regs,
               sizeof(s390_fp_regs));
        /* Set a new TLS ?  */
        if (clone_flags & CLONE_SETTLS)
                p->thread.acrs[0] = regs->gprs[6];
#else /* CONFIG_64BIT */
        /* Save the fpu registers to new thread structure. */
        save_fp_regs(&p->thread.fp_regs);
        /* Set a new TLS ?  */
        if (clone_flags & CLONE_SETTLS) {
                if (test_thread_flag(TIF_31BIT)) {
                        p->thread.acrs[0] = (unsigned int) regs->gprs[6];
                } else {
                        p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);
                        p->thread.acrs[1] = (unsigned int) regs->gprs[6];
                }
        }
#endif /* CONFIG_64BIT */
        /* start new process with ar4 pointing to the correct address space */
        p->thread.mm_segment = get_fs();
        /* Don't copy debug registers */
        memset(&p->thread.per_info,0,sizeof(p->thread.per_info));
 
        return 0;
}
 
asmlinkage long sys_fork(void)
{
        struct pt_regs *regs = task_pt_regs(current);
        return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL);
}
 
asmlinkage long sys_clone(void)
{
        struct pt_regs *regs = task_pt_regs(current);
        unsigned long clone_flags;
        unsigned long newsp;
        int __user *parent_tidptr, *child_tidptr;
 
        clone_flags = regs->gprs[3];
        newsp = regs->orig_gpr2;
        parent_tidptr = (int __user *) regs->gprs[4];
        child_tidptr = (int __user *) regs->gprs[5];
        if (!newsp)
                newsp = regs->gprs[15];
        return do_fork(clone_flags, newsp, regs, 0,
                       parent_tidptr, child_tidptr);
}
 
/*
 * This is trivial, and on the face of it looks like it
 * could equally well be done in user mode.
 *
 * Not so, for quite unobvious reasons - register pressure.
 * In user mode vfork() cannot have a stack frame, and if
 * done by calling the "clone()" system call directly, you
 * do not have enough call-clobbered registers to hold all
 * the information you need.
 */
asmlinkage long sys_vfork(void)
{
        struct pt_regs *regs = task_pt_regs(current);
        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
                       regs->gprs[15], regs, 0, NULL, NULL);
}
 
asmlinkage void execve_tail(void)
{
        task_lock(current);
        current->ptrace &= ~PT_DTRACE;
        task_unlock(current);
        current->thread.fp_regs.fpc = 0;
        if (MACHINE_HAS_IEEE)
                asm volatile("sfpc %0,%0" : : "d" (0));
}
 
/*
 * sys_execve() executes a new program.
 */
asmlinkage long sys_execve(void)
{
        struct pt_regs *regs = task_pt_regs(current);
        char *filename;
        unsigned long result;
        int rc;
 
        filename = getname((char __user *) regs->orig_gpr2);
        if (IS_ERR(filename)) {
                result = PTR_ERR(filename);
                goto out;
        }
        rc = do_execve(filename, (char __user * __user *) regs->gprs[3],
                       (char __user * __user *) regs->gprs[4], regs);
        if (rc) {
                result = rc;
                goto out_putname;
        }
        execve_tail();
        result = regs->gprs[2];
out_putname:
        putname(filename);
out:
        return result;
}
 
/*
 * fill in the FPU structure for a core dump.
 */
int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)
{
#ifndef CONFIG_64BIT
        /*
         * save fprs to current->thread.fp_regs to merge them with
         * the emulated registers and then copy the result to the dump.
         */
        save_fp_regs(&current->thread.fp_regs);
        memcpy(fpregs, &current->thread.fp_regs, sizeof(s390_fp_regs));
#else /* CONFIG_64BIT */
        save_fp_regs(fpregs);
#endif /* CONFIG_64BIT */
        return 1;
}
 
unsigned long get_wchan(struct task_struct *p)
{
        struct stack_frame *sf, *low, *high;
        unsigned long return_address;
        int count;
 
        if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p))
                return 0;
        low = task_stack_page(p);
        high = (struct stack_frame *) task_pt_regs(p);
        sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);
        if (sf <= low || sf > high)
                return 0;
        for (count = 0; count < 16; count++) {
                sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
                if (sf <= low || sf > high)
                        return 0;
                return_address = sf->gprs[8] & PSW_ADDR_INSN;
                if (!in_sched_functions(return_address))
                        return return_address;
        }
        return 0;
}
 

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[/] [test_project/] [trunk/] [linux_sd_driver/] [arch/] [s390/] [kernel/] [process.c] - Blame information for rev 63

Line No.	Rev	Author	Line
1	63	marcus.erl	`/*`
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
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/a.out.h>`
33			`#include <linux/interrupt.h>`
34			`#include <linux/delay.h>`
35			`#include <linux/reboot.h>`
36			`#include <linux/init.h>`
37			`#include <linux/module.h>`
38			`#include <linux/notifier.h>`
39
40			`#include <asm/uaccess.h>`
41			`#include <asm/pgtable.h>`
42			`#include <asm/system.h>`
43			`#include <asm/io.h>`
44			`#include <asm/processor.h>`
45			`#include <asm/irq.h>`
46			`#include <asm/timer.h>`
47			`#include <asm/cpu.h>`
48
49			`asmlinkage void ret_from_fork(void) asm ("ret_from_fork");`
50
51			`/*`
52			`* Return saved PC of a blocked thread. used in kernel/sched.`
53			`* resume in entry.S does not create a new stack frame, it`
54			`* just stores the registers %r6-%r15 to the frame given by`
55			`* schedule. We want to return the address of the caller of`
56			`* schedule, so we have to walk the backchain one time to`
57			`* find the frame schedule() store its return address.`
58			`*/`
59			`unsigned long thread_saved_pc(struct task_struct *tsk)`
60			`{`
61			`struct stack_frame sf, low, *high;`
62
63			`if (!tsk \|\| !task_stack_page(tsk))`
64			`return 0;`
65			`low = task_stack_page(tsk);`
66			`high = (struct stack_frame *) task_pt_regs(tsk);`
67			`sf = (struct stack_frame *) (tsk->thread.ksp & PSW_ADDR_INSN);`
68			`if (sf <= low \|\| sf > high)`
69			`return 0;`
70			`sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);`
71			`if (sf <= low \|\| sf > high)`
72			`return 0;`
73			`return sf->gprs[8];`
74			`}`
75
76			`/*`
77			`* Need to know about CPUs going idle?`
78			`*/`
79			`static ATOMIC_NOTIFIER_HEAD(idle_chain);`
80
81			`int register_idle_notifier(struct notifier_block *nb)`
82			`{`
83			`return atomic_notifier_chain_register(&idle_chain, nb);`
84			`}`
85			`EXPORT_SYMBOL(register_idle_notifier);`
86
87			`int unregister_idle_notifier(struct notifier_block *nb)`
88			`{`
89			`return atomic_notifier_chain_unregister(&idle_chain, nb);`
90			`}`
91			`EXPORT_SYMBOL(unregister_idle_notifier);`
92
93			`void do_monitor_call(struct pt_regs *regs, long interruption_code)`
94			`{`
95			`#ifdef CONFIG_SMP`
96			`struct s390_idle_data *idle;`
97
98			`idle = &__get_cpu_var(s390_idle);`
99			`spin_lock(&idle->lock);`
100			`idle->idle_time += get_clock() - idle->idle_enter;`
101			`idle->in_idle = 0;`
102			`spin_unlock(&idle->lock);`
103			`#endif`
104			`/* disable monitor call class 0 */`
105			`__ctl_clear_bit(8, 15);`
106
107			`atomic_notifier_call_chain(&idle_chain, S390_CPU_NOT_IDLE,`
108			`(void *)(long) smp_processor_id());`
109			`}`
110
111			`extern void s390_handle_mcck(void);`
112			`/*`
113			`* The idle loop on a S390...`
114			`*/`
115			`static void default_idle(void)`
116			`{`
117			`int cpu, rc;`
118			`#ifdef CONFIG_SMP`
119			`struct s390_idle_data *idle;`
120			`#endif`
121
122			`/* CPU is going idle. */`
123			`cpu = smp_processor_id();`
124
125			`local_irq_disable();`
126			`if (need_resched()) {`
127			`local_irq_enable();`
128			`return;`
129			`}`
130
131			`rc = atomic_notifier_call_chain(&idle_chain,`
132			`S390_CPU_IDLE, (void *)(long) cpu);`
133			`if (rc != NOTIFY_OK && rc != NOTIFY_DONE)`
134			`BUG();`
135			`if (rc != NOTIFY_OK) {`
136			`local_irq_enable();`
137			`return;`
138			`}`
139
140			`/* enable monitor call class 0 */`
141			`__ctl_set_bit(8, 15);`
142
143			`#ifdef CONFIG_HOTPLUG_CPU`
144			`if (cpu_is_offline(cpu)) {`
145			`preempt_enable_no_resched();`
146			`cpu_die();`
147			`}`
148			`#endif`
149
150			`local_mcck_disable();`
151			`if (test_thread_flag(TIF_MCCK_PENDING)) {`
152			`local_mcck_enable();`
153			`local_irq_enable();`
154			`s390_handle_mcck();`
155			`return;`
156			`}`
157			`#ifdef CONFIG_SMP`
158			`idle = &__get_cpu_var(s390_idle);`
159			`spin_lock(&idle->lock);`
160			`idle->idle_count++;`
161			`idle->in_idle = 1;`
162			`idle->idle_enter = get_clock();`
163			`spin_unlock(&idle->lock);`
164			`#endif`
165			`trace_hardirqs_on();`
166			`/* Wait for external, I/O or machine check interrupt. */`
167			`__load_psw_mask(psw_kernel_bits \| PSW_MASK_WAIT \|`
168			`PSW_MASK_IO \| PSW_MASK_EXT);`
169			`}`
170
171			`void cpu_idle(void)`
172			`{`
173			`for (;;) {`
174			`while (!need_resched())`
175			`default_idle();`
176
177			`preempt_enable_no_resched();`
178			`schedule();`
179			`preempt_disable();`
180			`}`
181			`}`
182
183			`void show_regs(struct pt_regs *regs)`
184			`{`
185			`struct task_struct *tsk = current;`
186
187			`printk("CPU: %d %s\n", task_thread_info(tsk)->cpu, print_tainted());`
188			`printk("Process %s (pid: %d, task: %p, ksp: %p)\n",`
189			`current->comm, task_pid_nr(current), (void *) tsk,`
190			`(void *) tsk->thread.ksp);`
191
192			`show_registers(regs);`
193			`/* Show stack backtrace if pt_regs is from kernel mode */`
194			`if (!(regs->psw.mask & PSW_MASK_PSTATE))`
195			`show_trace(NULL, (unsigned long *) regs->gprs[15]);`
196			`}`
197
198			`extern void kernel_thread_starter(void);`
199
200			`asm(`
201			`".align 4\n"`
202			`"kernel_thread_starter:\n"`
203			`" la 2,0(10)\n"`
204			`" basr 14,9\n"`
205			`" la 2,0\n"`
206			`" br 11\n");`
207
208			`int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)`
209			`{`
210			`struct pt_regs regs;`
211
212			`memset(&regs, 0, sizeof(regs));`
213			`regs.psw.mask = psw_kernel_bits \| PSW_MASK_IO \| PSW_MASK_EXT;`
214			`regs.psw.addr = (unsigned long) kernel_thread_starter \| PSW_ADDR_AMODE;`
215			`regs.gprs[9] = (unsigned long) fn;`
216			`regs.gprs[10] = (unsigned long) arg;`
217			`regs.gprs[11] = (unsigned long) do_exit;`
218			`regs.orig_gpr2 = -1;`
219
220			`/* Ok, create the new process.. */`
221			`return do_fork(flags \| CLONE_VM \| CLONE_UNTRACED,`
222			`0, &regs, 0, NULL, NULL);`
223			`}`
224
225			`/*`
226			`* Free current thread data structures etc..`
227			`*/`
228			`void exit_thread(void)`
229			`{`
230			`}`
231
232			`void flush_thread(void)`
233			`{`
234			`clear_used_math();`
235			`clear_tsk_thread_flag(current, TIF_USEDFPU);`
236			`}`
237
238			`void release_thread(struct task_struct *dead_task)`
239			`{`
240			`}`
241
242			`int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,`
243			`unsigned long unused,`
244			`struct task_struct * p, struct pt_regs * regs)`
245			`{`
246			`struct fake_frame`
247			`{`
248			`struct stack_frame sf;`
249			`struct pt_regs childregs;`
250			`} *frame;`
251
252			`frame = container_of(task_pt_regs(p), struct fake_frame, childregs);`
253			`p->thread.ksp = (unsigned long) frame;`
254			`/* Store access registers to kernel stack of new process. */`
255			`frame->childregs = *regs;`
256			`frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */`
257			`frame->childregs.gprs[15] = new_stackp;`
258			`frame->sf.back_chain = 0;`
259
260			`/* new return point is ret_from_fork */`
261			`frame->sf.gprs[8] = (unsigned long) ret_from_fork;`
262
263			`/* fake return stack for resume(), don't go back to schedule */`
264			`frame->sf.gprs[9] = (unsigned long) frame;`
265
266			`/* Save access registers to new thread structure. */`
267			`save_access_regs(&p->thread.acrs[0]);`
268
269			`#ifndef CONFIG_64BIT`
270			`/*`
271			`* save fprs to current->thread.fp_regs to merge them with`
272			`* the emulated registers and then copy the result to the child.`
273			`*/`
274			`save_fp_regs(&current->thread.fp_regs);`
275			`memcpy(&p->thread.fp_regs, &current->thread.fp_regs,`
276			`sizeof(s390_fp_regs));`
277			`/* Set a new TLS ? */`
278			`if (clone_flags & CLONE_SETTLS)`
279			`p->thread.acrs[0] = regs->gprs[6];`
280			`#else /* CONFIG_64BIT */`
281			`/* Save the fpu registers to new thread structure. */`
282			`save_fp_regs(&p->thread.fp_regs);`
283			`/* Set a new TLS ? */`
284			`if (clone_flags & CLONE_SETTLS) {`
285			`if (test_thread_flag(TIF_31BIT)) {`
286			`p->thread.acrs[0] = (unsigned int) regs->gprs[6];`
287			`} else {`
288			`p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32);`
289			`p->thread.acrs[1] = (unsigned int) regs->gprs[6];`
290			`}`
291			`}`
292			`#endif /* CONFIG_64BIT */`
293			`/* start new process with ar4 pointing to the correct address space */`
294			`p->thread.mm_segment = get_fs();`
295			`/* Don't copy debug registers */`
296			`memset(&p->thread.per_info,0,sizeof(p->thread.per_info));`
297
298			`return 0;`
299			`}`
300
301			`asmlinkage long sys_fork(void)`
302			`{`
303			`struct pt_regs *regs = task_pt_regs(current);`
304			`return do_fork(SIGCHLD, regs->gprs[15], regs, 0, NULL, NULL);`
305			`}`
306
307			`asmlinkage long sys_clone(void)`
308			`{`
309			`struct pt_regs *regs = task_pt_regs(current);`
310			`unsigned long clone_flags;`
311			`unsigned long newsp;`
312			`int __user parent_tidptr, child_tidptr;`
313
314			`clone_flags = regs->gprs[3];`
315			`newsp = regs->orig_gpr2;`
316			`parent_tidptr = (int __user *) regs->gprs[4];`
317			`child_tidptr = (int __user *) regs->gprs[5];`
318			`if (!newsp)`
319			`newsp = regs->gprs[15];`
320			`return do_fork(clone_flags, newsp, regs, 0,`
321			`parent_tidptr, child_tidptr);`
322			`}`
323
324			`/*`
325			`* This is trivial, and on the face of it looks like it`
326			`* could equally well be done in user mode.`
327			`*`
328			`* Not so, for quite unobvious reasons - register pressure.`
329			`* In user mode vfork() cannot have a stack frame, and if`
330			`* done by calling the "clone()" system call directly, you`
331			`* do not have enough call-clobbered registers to hold all`
332			`* the information you need.`
333			`*/`
334			`asmlinkage long sys_vfork(void)`
335			`{`
336			`struct pt_regs *regs = task_pt_regs(current);`
337			`return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD,`
338			`regs->gprs[15], regs, 0, NULL, NULL);`
339			`}`
340
341			`asmlinkage void execve_tail(void)`
342			`{`
343			`task_lock(current);`
344			`current->ptrace &= ~PT_DTRACE;`
345			`task_unlock(current);`
346			`current->thread.fp_regs.fpc = 0;`
347			`if (MACHINE_HAS_IEEE)`
348			`asm volatile("sfpc %0,%0" : : "d" (0));`
349			`}`
350
351			`/*`
352			`* sys_execve() executes a new program.`
353			`*/`
354			`asmlinkage long sys_execve(void)`
355			`{`
356			`struct pt_regs *regs = task_pt_regs(current);`
357			`char *filename;`
358			`unsigned long result;`
359			`int rc;`
360
361			`filename = getname((char __user *) regs->orig_gpr2);`
362			`if (IS_ERR(filename)) {`
363			`result = PTR_ERR(filename);`
364			`goto out;`
365			`}`
366			`rc = do_execve(filename, (char __user * __user *) regs->gprs[3],`
367			`(char __user * __user *) regs->gprs[4], regs);`
368			`if (rc) {`
369			`result = rc;`
370			`goto out_putname;`
371			`}`
372			`execve_tail();`
373			`result = regs->gprs[2];`
374			`out_putname:`
375			`putname(filename);`
376			`out:`
377			`return result;`
378			`}`
379
380			`/*`
381			`* fill in the FPU structure for a core dump.`
382			`*/`
383			`int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs)`
384			`{`
385			`#ifndef CONFIG_64BIT`
386			`/*`
387			`* save fprs to current->thread.fp_regs to merge them with`
388			`* the emulated registers and then copy the result to the dump.`
389			`*/`
390			`save_fp_regs(&current->thread.fp_regs);`
391			`memcpy(fpregs, &current->thread.fp_regs, sizeof(s390_fp_regs));`
392			`#else /* CONFIG_64BIT */`
393			`save_fp_regs(fpregs);`
394			`#endif /* CONFIG_64BIT */`
395			`return 1;`
396			`}`
397
398			`unsigned long get_wchan(struct task_struct *p)`
399			`{`
400			`struct stack_frame sf, low, *high;`
401			`unsigned long return_address;`
402			`int count;`
403
404			`if (!p \|\| p == current \|\| p->state == TASK_RUNNING \|\| !task_stack_page(p))`
405			`return 0;`
406			`low = task_stack_page(p);`
407			`high = (struct stack_frame *) task_pt_regs(p);`
408			`sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);`
409			`if (sf <= low \|\| sf > high)`
410			`return 0;`
411			`for (count = 0; count < 16; count++) {`
412			`sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);`
413			`if (sf <= low \|\| sf > high)`
414			`return 0;`
415			`return_address = sf->gprs[8] & PSW_ADDR_INSN;`
416			`if (!in_sched_functions(return_address))`
417			`return return_address;`
418			`}`
419			`return 0;`
420			`}`
421