[mirror_ubuntu-zesty-kernel.git] / arch / parisc / kernel / process.c

/*
 *    PARISC Architecture-dependent parts of process handling
 *    based on the work for i386
 *
 *    Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
 *    Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
 *    Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
 *    Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
 *    Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
 *    Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
 *    Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
 *    Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
 *    Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
 *    Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
 *    Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
 *    Copyright (C) 2001-2002 Helge Deller <deller at parisc-linux.org>
 *    Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
 *
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <stdarg.h>

#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/kallsyms.h>

#include <asm/io.h>
#include <asm/asm-offsets.h>
#include <asm/pdc.h>
#include <asm/pdc_chassis.h>
#include <asm/pgalloc.h>
#include <asm/uaccess.h>
#include <asm/unwind.h>

/*
 * The idle thread. There's no useful work to be
 * done, so just try to conserve power and have a
 * low exit latency (ie sit in a loop waiting for
 * somebody to say that they'd like to reschedule)
 */
void cpu_idle(void)
{
	set_thread_flag(TIF_POLLING_NRFLAG);

	/* endless idle loop with no priority at all */
	while (1) {
		while (!need_resched())
			barrier();
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
		check_pgt_cache();
	}
}


#define COMMAND_GLOBAL  F_EXTEND(0xfffe0030)
#define CMD_RESET       5       /* reset any module */

/*
** The Wright Brothers and Gecko systems have a H/W problem
** (Lasi...'nuf said) may cause a broadcast reset to lockup
** the system. An HVERSION dependent PDC call was developed
** to perform a "safe", platform specific broadcast reset instead
** of kludging up all the code.
**
** Older machines which do not implement PDC_BROADCAST_RESET will
** return (with an error) and the regular broadcast reset can be
** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
** the PDC call will not return (the system will be reset).
*/
void machine_restart(char *cmd)
{
#ifdef FASTBOOT_SELFTEST_SUPPORT
	/*
	 ** If user has modified the Firmware Selftest Bitmap,
	 ** run the tests specified in the bitmap after the
	 ** system is rebooted w/PDC_DO_RESET.
	 **
	 ** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
	 **
	 ** Using "directed resets" at each processor with the MEM_TOC
	 ** vector cleared will also avoid running destructive
	 ** memory self tests. (Not implemented yet)
	 */
	if (ftc_bitmap) {
		pdc_do_firm_test_reset(ftc_bitmap);
	}
#endif
	/* set up a new led state on systems shipped with a LED State panel */
	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	
	/* "Normal" system reset */
	pdc_do_reset();

	/* Nope...box should reset with just CMD_RESET now */
	gsc_writel(CMD_RESET, COMMAND_GLOBAL);

	/* Wait for RESET to lay us to rest. */
	while (1) ;

}

void machine_halt(void)
{
	/*
	** The LED/ChassisCodes are updated by the led_halt()
	** function, called by the reboot notifier chain.
	*/
}

void (*chassis_power_off)(void);

/*
 * This routine is called from sys_reboot to actually turn off the
 * machine 
 */
void machine_power_off(void)
{
	/* If there is a registered power off handler, call it. */
	if (chassis_power_off)
		chassis_power_off();

	/* Put the soft power button back under hardware control.
	 * If the user had already pressed the power button, the
	 * following call will immediately power off. */
	pdc_soft_power_button(0);
	
	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
		
	/* It seems we have no way to power the system off via
	 * software. The user has to press the button himself. */

	printk(KERN_EMERG "System shut down completed.\n"
	       KERN_EMERG "Please power this system off now.");
}

void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);

/*
 * Create a kernel thread
 */

extern pid_t __kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{

	/*
	 * FIXME: Once we are sure we don't need any debug here,
	 *	  kernel_thread can become a #define.
	 */

	return __kernel_thread(fn, arg, flags);
}
EXPORT_SYMBOL(kernel_thread);

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
}

void flush_thread(void)
{
	/* Only needs to handle fpu stuff or perf monitors.
	** REVISIT: several arches implement a "lazy fpu state".
	*/
	set_fs(USER_DS);
}

void release_thread(struct task_struct *dead_task)
{
}

/*
 * Fill in the FPU structure for a core dump.
 */

int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
{
	if (regs == NULL)
		return 0;

	memcpy(r, regs->fr, sizeof *r);
	return 1;
}

int dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *r)
{
	memcpy(r, tsk->thread.regs.fr, sizeof(*r));
	return 1;
}

/* Note that "fork()" is implemented in terms of clone, with
   parameters (SIGCHLD, regs->gr[30], regs). */
int
sys_clone(unsigned long clone_flags, unsigned long usp,
	  struct pt_regs *regs)
{
  	/* Arugments from userspace are:
	   r26 = Clone flags.
	   r25 = Child stack.
	   r24 = parent_tidptr.
	   r23 = Is the TLS storage descriptor 
	   r22 = child_tidptr 
	   
	   However, these last 3 args are only examined
	   if the proper flags are set. */
	int __user *child_tidptr;
	int __user *parent_tidptr;

	/* usp must be word aligned.  This also prevents users from
	 * passing in the value 1 (which is the signal for a special
	 * return for a kernel thread) */
	usp = ALIGN(usp, 4);

	/* A zero value for usp means use the current stack */
	if (usp == 0)
	  usp = regs->gr[30];

	if (clone_flags & CLONE_PARENT_SETTID)
	  parent_tidptr = (int __user *)regs->gr[24];
	else
	  parent_tidptr = NULL;
	
	if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID))
	  child_tidptr = (int __user *)regs->gr[22];
	else
	  child_tidptr = NULL;

	return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
}

int
sys_vfork(struct pt_regs *regs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
}

int
copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
	    unsigned long unused,	/* in ia64 this is "user_stack_size" */
	    struct task_struct * p, struct pt_regs * pregs)
{
	struct pt_regs * cregs = &(p->thread.regs);
	void *stack = task_stack_page(p);
	
	/* We have to use void * instead of a function pointer, because
	 * function pointers aren't a pointer to the function on 64-bit.
	 * Make them const so the compiler knows they live in .text */
	extern void * const ret_from_kernel_thread;
	extern void * const child_return;
#ifdef CONFIG_HPUX
	extern void * const hpux_child_return;
#endif

	*cregs = *pregs;

	/* Set the return value for the child.  Note that this is not
           actually restored by the syscall exit path, but we put it
           here for consistency in case of signals. */
	cregs->gr[28] = 0; /* child */

	/*
	 * We need to differentiate between a user fork and a
	 * kernel fork. We can't use user_mode, because the
	 * the syscall path doesn't save iaoq. Right now
	 * We rely on the fact that kernel_thread passes
	 * in zero for usp.
	 */
	if (usp == 1) {
		/* kernel thread */
		cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
		/* Must exit via ret_from_kernel_thread in order
		 * to call schedule_tail()
		 */
		cregs->kpc = (unsigned long) &ret_from_kernel_thread;
		/*
		 * Copy function and argument to be called from
		 * ret_from_kernel_thread.
		 */
#ifdef __LP64__
		cregs->gr[27] = pregs->gr[27];
#endif
		cregs->gr[26] = pregs->gr[26];
		cregs->gr[25] = pregs->gr[25];
	} else {
		/* user thread */
		/*
		 * Note that the fork wrappers are responsible
		 * for setting gr[21].
		 */

		/* Use same stack depth as parent */
		cregs->ksp = (unsigned long)stack
			+ (pregs->gr[21] & (THREAD_SIZE - 1));
		cregs->gr[30] = usp;
		if (p->personality == PER_HPUX) {
#ifdef CONFIG_HPUX
			cregs->kpc = (unsigned long) &hpux_child_return;
#else
			BUG();
#endif
		} else {
			cregs->kpc = (unsigned long) &child_return;
		}
		/* Setup thread TLS area from the 4th parameter in clone */
		if (clone_flags & CLONE_SETTLS)
		  cregs->cr27 = pregs->gr[23];
	
	}

	return 0;
}

unsigned long thread_saved_pc(struct task_struct *t)
{
	return t->thread.regs.kpc;
}

/*
 * sys_execve() executes a new program.
 */

asmlinkage int sys_execve(struct pt_regs *regs)
{
	int error;
	char *filename;

	filename = getname((const char __user *) regs->gr[26]);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;
	error = do_execve(filename, (char __user * __user *) regs->gr[25],
		(char __user * __user *) regs->gr[24], regs);
	if (error == 0) {
		task_lock(current);
		current->ptrace &= ~PT_DTRACE;
		task_unlock(current);
	}
	putname(filename);
out:

	return error;
}

extern int __execve(const char *filename, char *const argv[],
		char *const envp[], struct task_struct *task);
int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
	return __execve(filename, argv, envp, current);
}

unsigned long
get_wchan(struct task_struct *p)
{
	struct unwind_frame_info info;
	unsigned long ip;
	int count = 0;
	/*
	 * These bracket the sleeping functions..
	 */

	unwind_frame_init_from_blocked_task(&info, p);
	do {
		if (unwind_once(&info) < 0)
			return 0;
		ip = info.ip;
		if (!in_sched_functions(ip))
			return ip;
	} while (count++ < 16);
	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* PARISC Architecture-dependent parts of process handling
	3	* based on the work for i386
	4	*
	5	* Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
	6	* Copyright (C) 2000 Martin K Petersen <mkp at mkp.net>
	7	* Copyright (C) 2000 John Marvin <jsm at parisc-linux.org>
	8	* Copyright (C) 2000 David Huggins-Daines <dhd with pobox.org>
	9	* Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
	10	* Copyright (C) 2000 Philipp Rumpf <prumpf with tux.org>
	11	* Copyright (C) 2000 David Kennedy <dkennedy with linuxcare.com>
b2450cc1	12	* Copyright (C) 2000 Richard Hirst <rhirst with parisc-linux.org>
1da177e4 LT	13	* Copyright (C) 2000 Grant Grundler <grundler with parisc-linux.org>
	14	* Copyright (C) 2001 Alan Modra <amodra at parisc-linux.org>
	15	* Copyright (C) 2001-2002 Ryan Bradetich <rbrad at parisc-linux.org>
	16	* Copyright (C) 2001-2002 Helge Deller <deller at parisc-linux.org>
	17	* Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org>
	18	*
	19	*
	20	* This program is free software; you can redistribute it and/or modify
	21	* it under the terms of the GNU General Public License as published by
	22	* the Free Software Foundation; either version 2 of the License, or
	23	* (at your option) any later version.
	24	*
	25	* This program is distributed in the hope that it will be useful,
	26	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	27	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	28	* GNU General Public License for more details.
	29	*
	30	* You should have received a copy of the GNU General Public License
	31	* along with this program; if not, write to the Free Software
	32	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	33	*/
	34
	35	#include <stdarg.h>
	36
	37	#include <linux/elf.h>
	38	#include <linux/errno.h>
	39	#include <linux/kernel.h>
	40	#include <linux/mm.h>
	41	#include <linux/module.h>
	42	#include <linux/personality.h>
	43	#include <linux/ptrace.h>
	44	#include <linux/sched.h>
	45	#include <linux/stddef.h>
	46	#include <linux/unistd.h>
	47	#include <linux/kallsyms.h>
	48
	49	#include <asm/io.h>
0013a854	50	#include <asm/asm-offsets.h>
1da177e4 LT	51	#include <asm/pdc.h>
	52	#include <asm/pdc_chassis.h>
	53	#include <asm/pgalloc.h>
	54	#include <asm/uaccess.h>
	55	#include <asm/unwind.h>
	56
1da177e4 LT	57	/*
	58	* The idle thread. There's no useful work to be
	59	* done, so just try to conserve power and have a
	60	* low exit latency (ie sit in a loop waiting for
	61	* somebody to say that they'd like to reschedule)
	62	*/
	63	void cpu_idle(void)
	64	{
64c7c8f8 NP	65	set_thread_flag(TIF_POLLING_NRFLAG);
64c7c8f8 NP	66
1da177e4 LT	67	/* endless idle loop with no priority at all */
	68	while (1) {
	69	while (!need_resched())
	70	barrier();
5bfb5d69	71	preempt_enable_no_resched();
1da177e4	72	schedule();
5bfb5d69	73	preempt_disable();
1da177e4 LT	74	check_pgt_cache();
	75	}
	76	}
	77
	78
10992092	79	#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
1da177e4 LT	80	#define CMD_RESET 5 /* reset any module */
	81
	82	/*
	83	** The Wright Brothers and Gecko systems have a H/W problem
	84	** (Lasi...'nuf said) may cause a broadcast reset to lockup
	85	** the system. An HVERSION dependent PDC call was developed
	86	** to perform a "safe", platform specific broadcast reset instead
	87	** of kludging up all the code.
	88	**
	89	** Older machines which do not implement PDC_BROADCAST_RESET will
	90	** return (with an error) and the regular broadcast reset can be
	91	** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
	92	** the PDC call will not return (the system will be reset).
	93	*/
	94	void machine_restart(char *cmd)
	95	{
	96	#ifdef FASTBOOT_SELFTEST_SUPPORT
	97	/*
	98	** If user has modified the Firmware Selftest Bitmap,
	99	** run the tests specified in the bitmap after the
	100	** system is rebooted w/PDC_DO_RESET.
	101	**
	102	** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
	103	**
	104	** Using "directed resets" at each processor with the MEM_TOC
	105	** vector cleared will also avoid running destructive
	106	** memory self tests. (Not implemented yet)
	107	*/
	108	if (ftc_bitmap) {
	109	pdc_do_firm_test_reset(ftc_bitmap);
	110	}
	111	#endif
	112	/* set up a new led state on systems shipped with a LED State panel */
	113	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	114
	115	/* "Normal" system reset */
	116	pdc_do_reset();
	117
	118	/* Nope...box should reset with just CMD_RESET now */
	119	gsc_writel(CMD_RESET, COMMAND_GLOBAL);
	120
	121	/* Wait for RESET to lay us to rest. */
	122	while (1) ;
	123
	124	}
	125
1da177e4 LT	126	void machine_halt(void)
	127	{
	128	/*
	129	** The LED/ChassisCodes are updated by the led_halt()
	130	** function, called by the reboot notifier chain.
	131	*/
	132	}
	133
85509c00	134	void (*chassis_power_off)(void);
1da177e4 LT	135
	136	/*
	137	* This routine is called from sys_reboot to actually turn off the
	138	* machine
	139	*/
	140	void machine_power_off(void)
	141	{
	142	/* If there is a registered power off handler, call it. */
85509c00 KM	143	if (chassis_power_off)
85509c00 KM	144	chassis_power_off();
1da177e4 LT	145
	146	/* Put the soft power button back under hardware control.
	147	* If the user had already pressed the power button, the
	148	* following call will immediately power off. */
	149	pdc_soft_power_button(0);
	150
	151	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	152
	153	/* It seems we have no way to power the system off via
	154	* software. The user has to press the button himself. */
	155
	156	printk(KERN_EMERG "System shut down completed.\n"
	157	KERN_EMERG "Please power this system off now.");
	158	}
	159
85509c00 KM	160	void (*pm_power_off)(void) = machine_power_off;
85509c00 KM	161	EXPORT_SYMBOL(pm_power_off);
1da177e4 LT	162
	163	/*
	164	* Create a kernel thread
	165	*/
	166
	167	extern pid_t __kernel_thread(int (fn)(void ), void *arg, unsigned long flags);
	168	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
	169	{
	170
	171	/*
	172	* FIXME: Once we are sure we don't need any debug here,
	173	* kernel_thread can become a #define.
	174	*/
	175
	176	return __kernel_thread(fn, arg, flags);
	177	}
	178	EXPORT_SYMBOL(kernel_thread);
	179
	180	/*
	181	* Free current thread data structures etc..
	182	*/
	183	void exit_thread(void)
	184	{
	185	}
	186
	187	void flush_thread(void)
	188	{
	189	/* Only needs to handle fpu stuff or perf monitors.
	190	** REVISIT: several arches implement a "lazy fpu state".
	191	*/
	192	set_fs(USER_DS);
	193	}
	194
	195	void release_thread(struct task_struct *dead_task)
	196	{
	197	}
	198
	199	/*
	200	* Fill in the FPU structure for a core dump.
	201	*/
	202
	203	int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
	204	{
	205	if (regs == NULL)
	206	return 0;
	207
	208	memcpy(r, regs->fr, sizeof *r);
	209	return 1;
	210	}
	211
	212	int dump_task_fpu (struct task_struct tsk, elf_fpregset_t r)
	213	{
	214	memcpy(r, tsk->thread.regs.fr, sizeof(*r));
	215	return 1;
	216	}
	217
	218	/* Note that "fork()" is implemented in terms of clone, with
	219	parameters (SIGCHLD, regs->gr[30], regs). */
	220	int
	221	sys_clone(unsigned long clone_flags, unsigned long usp,
	222	struct pt_regs *regs)
	223	{
b2450cc1 CD	224	/* Arugments from userspace are:
	225	r26 = Clone flags.
	226	r25 = Child stack.
	227	r24 = parent_tidptr.
	228	r23 = Is the TLS storage descriptor
	229	r22 = child_tidptr
	230
	231	However, these last 3 args are only examined
	232	if the proper flags are set. */
	233	int __user *child_tidptr;
	234	int __user *parent_tidptr;
1da177e4 LT	235
	236	/* usp must be word aligned. This also prevents users from
	237	* passing in the value 1 (which is the signal for a special
	238	* return for a kernel thread) */
	239	usp = ALIGN(usp, 4);
	240
	241	/* A zero value for usp means use the current stack */
b2450cc1 CD	242	if (usp == 0)
b2450cc1 CD	243	usp = regs->gr[30];
1da177e4	244
b2450cc1 CD	245	if (clone_flags & CLONE_PARENT_SETTID)
	246	parent_tidptr = (int __user *)regs->gr[24];
	247	else
	248	parent_tidptr = NULL;
	249
	250	if (clone_flags & (CLONE_CHILD_SETTID \| CLONE_CHILD_CLEARTID))
	251	child_tidptr = (int __user *)regs->gr[22];
	252	else
	253	child_tidptr = NULL;
	254
	255	return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
1da177e4 LT	256	}
	257
	258	int
	259	sys_vfork(struct pt_regs *regs)
	260	{
	261	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
	262	}
	263
	264	int
	265	copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
	266	unsigned long unused, /* in ia64 this is "user_stack_size" */
	267	struct task_struct * p, struct pt_regs * pregs)
	268	{
	269	struct pt_regs * cregs = &(p->thread.regs);
40f1f0de	270	void *stack = task_stack_page(p);
1da177e4 LT	271
	272	/* We have to use void * instead of a function pointer, because
	273	* function pointers aren't a pointer to the function on 64-bit.
	274	* Make them const so the compiler knows they live in .text */
	275	extern void * const ret_from_kernel_thread;
	276	extern void * const child_return;
	277	#ifdef CONFIG_HPUX
	278	extern void * const hpux_child_return;
	279	#endif
	280
	281	cregs = pregs;
	282
	283	/* Set the return value for the child. Note that this is not
	284	actually restored by the syscall exit path, but we put it
	285	here for consistency in case of signals. */
	286	cregs->gr[28] = 0; /* child */
	287
	288	/*
	289	* We need to differentiate between a user fork and a
	290	* kernel fork. We can't use user_mode, because the
	291	* the syscall path doesn't save iaoq. Right now
	292	* We rely on the fact that kernel_thread passes
	293	* in zero for usp.
	294	*/
	295	if (usp == 1) {
	296	/* kernel thread */
40f1f0de	297	cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
1da177e4 LT	298	/* Must exit via ret_from_kernel_thread in order
	299	* to call schedule_tail()
	300	*/
	301	cregs->kpc = (unsigned long) &ret_from_kernel_thread;
	302	/*
	303	* Copy function and argument to be called from
	304	* ret_from_kernel_thread.
	305	*/
	306	#ifdef __LP64__
	307	cregs->gr[27] = pregs->gr[27];
	308	#endif
	309	cregs->gr[26] = pregs->gr[26];
	310	cregs->gr[25] = pregs->gr[25];
	311	} else {
	312	/* user thread */
	313	/*
	314	* Note that the fork wrappers are responsible
	315	* for setting gr[21].
	316	*/
	317
	318	/* Use same stack depth as parent */
40f1f0de	319	cregs->ksp = (unsigned long)stack
1da177e4 LT	320	+ (pregs->gr[21] & (THREAD_SIZE - 1));
	321	cregs->gr[30] = usp;
	322	if (p->personality == PER_HPUX) {
	323	#ifdef CONFIG_HPUX
	324	cregs->kpc = (unsigned long) &hpux_child_return;
	325	#else
	326	BUG();
	327	#endif
	328	} else {
	329	cregs->kpc = (unsigned long) &child_return;
	330	}
b2450cc1 CD	331	/* Setup thread TLS area from the 4th parameter in clone */
	332	if (clone_flags & CLONE_SETTLS)
	333	cregs->cr27 = pregs->gr[23];
	334
1da177e4 LT	335	}
	336
	337	return 0;
	338	}
	339
	340	unsigned long thread_saved_pc(struct task_struct *t)
	341	{
	342	return t->thread.regs.kpc;
	343	}
	344
	345	/*
	346	* sys_execve() executes a new program.
	347	*/
	348
	349	asmlinkage int sys_execve(struct pt_regs *regs)
	350	{
	351	int error;
	352	char *filename;
	353
	354	filename = getname((const char __user *) regs->gr[26]);
	355	error = PTR_ERR(filename);
	356	if (IS_ERR(filename))
	357	goto out;
c2c4798e MW	358	error = do_execve(filename, (char __user * __user *) regs->gr[25],
c2c4798e MW	359	(char __user * __user *) regs->gr[24], regs);
1da177e4 LT	360	if (error == 0) {
	361	task_lock(current);
	362	current->ptrace &= ~PT_DTRACE;
	363	task_unlock(current);
	364	}
	365	putname(filename);
	366	out:
	367
	368	return error;
	369	}
	370
3db03b4a AB	371	extern int __execve(const char filename, char const argv[],
	372	char const envp[], struct task_struct task);
	373	int kernel_execve(const char filename, char const argv[], char *const envp[])
	374	{
	375	return __execve(filename, argv, envp, current);
	376	}
	377
	378	unsigned long
1da177e4 LT	379	get_wchan(struct task_struct *p)
	380	{
	381	struct unwind_frame_info info;
	382	unsigned long ip;
	383	int count = 0;
	384	/*
	385	* These bracket the sleeping functions..
	386	*/
	387
	388	unwind_frame_init_from_blocked_task(&info, p);
	389	do {
	390	if (unwind_once(&info) < 0)
	391	return 0;
	392	ip = info.ip;
	393	if (!in_sched_functions(ip))
	394	return ip;
	395	} while (count++ < 16);
	396	return 0;
	397	}