[deliverable/linux.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) 2001-2007 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/fs.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/kallsyms.h>
#include <linux/uaccess.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/unwind.h>
#include <asm/sections.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();
		schedule_preempt_disabled();
		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"
	       "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".
	*/
}

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 *parent_tidptr = (int __user *)regs->gr[24];
	int __user *child_tidptr  = (int __user *)regs->gr[22];

	/* 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];

	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(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 CONFIG_64BIT
		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 (personality(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,
			  (const char __user *const __user *) regs->gr[25],
			  (const char __user *const __user *) regs->gr[24],
			  regs);
	putname(filename);
out:

	return error;
}

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

	if (!p || p == current || p->state == TASK_RUNNING)
		return 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;
}

#ifdef CONFIG_64BIT
void *dereference_function_descriptor(void *ptr)
{
	Elf64_Fdesc *desc = ptr;
	void *p;

	if (!probe_kernel_address(&desc->addr, p))
		ptr = p;
	return ptr;
}
#endif
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>
a8f44e38	16	* Copyright (C) 2001-2007 Helge Deller <deller at parisc-linux.org>
1da177e4 LT	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>
4e950f6f	41	#include <linux/fs.h>
1da177e4 LT	42	#include <linux/module.h>
	43	#include <linux/personality.h>
	44	#include <linux/ptrace.h>
	45	#include <linux/sched.h>
5a0e3ad6	46	#include <linux/slab.h>
1da177e4 LT	47	#include <linux/stddef.h>
	48	#include <linux/unistd.h>
	49	#include <linux/kallsyms.h>
b609308e	50	#include <linux/uaccess.h>
1da177e4 LT	51
1da177e4 LT	52	#include <asm/io.h>
0013a854	53	#include <asm/asm-offsets.h>
1da177e4 LT	54	#include <asm/pdc.h>
	55	#include <asm/pdc_chassis.h>
	56	#include <asm/pgalloc.h>
1da177e4	57	#include <asm/unwind.h>
b609308e	58	#include <asm/sections.h>
1da177e4	59
1da177e4 LT	60	/*
	61	* The idle thread. There's no useful work to be
	62	* done, so just try to conserve power and have a
	63	* low exit latency (ie sit in a loop waiting for
	64	* somebody to say that they'd like to reschedule)
	65	*/
	66	void cpu_idle(void)
	67	{
64c7c8f8 NP	68	set_thread_flag(TIF_POLLING_NRFLAG);
64c7c8f8 NP	69
1da177e4 LT	70	/* endless idle loop with no priority at all */
	71	while (1) {
	72	while (!need_resched())
	73	barrier();
bd2f5536	74	schedule_preempt_disabled();
1da177e4 LT	75	check_pgt_cache();
	76	}
	77	}
	78
	79
10992092	80	#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
1da177e4 LT	81	#define CMD_RESET 5 /* reset any module */
	82
	83	/*
	84	** The Wright Brothers and Gecko systems have a H/W problem
	85	** (Lasi...'nuf said) may cause a broadcast reset to lockup
	86	** the system. An HVERSION dependent PDC call was developed
	87	** to perform a "safe", platform specific broadcast reset instead
	88	** of kludging up all the code.
	89	**
	90	** Older machines which do not implement PDC_BROADCAST_RESET will
	91	** return (with an error) and the regular broadcast reset can be
	92	** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
	93	** the PDC call will not return (the system will be reset).
	94	*/
	95	void machine_restart(char *cmd)
	96	{
	97	#ifdef FASTBOOT_SELFTEST_SUPPORT
	98	/*
	99	** If user has modified the Firmware Selftest Bitmap,
	100	** run the tests specified in the bitmap after the
	101	** system is rebooted w/PDC_DO_RESET.
	102	**
	103	** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
	104	**
	105	** Using "directed resets" at each processor with the MEM_TOC
	106	** vector cleared will also avoid running destructive
	107	** memory self tests. (Not implemented yet)
	108	*/
	109	if (ftc_bitmap) {
	110	pdc_do_firm_test_reset(ftc_bitmap);
	111	}
	112	#endif
	113	/* set up a new led state on systems shipped with a LED State panel */
	114	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	115
	116	/* "Normal" system reset */
	117	pdc_do_reset();
	118
	119	/* Nope...box should reset with just CMD_RESET now */
	120	gsc_writel(CMD_RESET, COMMAND_GLOBAL);
	121
	122	/* Wait for RESET to lay us to rest. */
	123	while (1) ;
	124
	125	}
	126
1da177e4 LT	127	void machine_halt(void)
	128	{
	129	/*
	130	** The LED/ChassisCodes are updated by the led_halt()
	131	** function, called by the reboot notifier chain.
	132	*/
	133	}
	134
85509c00	135	void (*chassis_power_off)(void);
1da177e4 LT	136
	137	/*
	138	* This routine is called from sys_reboot to actually turn off the
	139	* machine
	140	*/
	141	void machine_power_off(void)
	142	{
	143	/* If there is a registered power off handler, call it. */
85509c00 KM	144	if (chassis_power_off)
85509c00 KM	145	chassis_power_off();
1da177e4 LT	146
	147	/* Put the soft power button back under hardware control.
	148	* If the user had already pressed the power button, the
	149	* following call will immediately power off. */
	150	pdc_soft_power_button(0);
	151
	152	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	153
	154	/* It seems we have no way to power the system off via
	155	* software. The user has to press the button himself. */
	156
	157	printk(KERN_EMERG "System shut down completed.\n"
ad361c98	158	"Please power this system off now.");
1da177e4 LT	159	}
1da177e4 LT	160
85509c00 KM	161	void (*pm_power_off)(void) = machine_power_off;
85509c00 KM	162	EXPORT_SYMBOL(pm_power_off);
1da177e4 LT	163
	164	/*
	165	* Create a kernel thread
	166	*/
	167
	168	extern pid_t __kernel_thread(int (fn)(void ), void *arg, unsigned long flags);
	169	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
	170	{
	171
	172	/*
	173	* FIXME: Once we are sure we don't need any debug here,
	174	* kernel_thread can become a #define.
	175	*/
	176
	177	return __kernel_thread(fn, arg, flags);
	178	}
	179	EXPORT_SYMBOL(kernel_thread);
	180
	181	/*
	182	* Free current thread data structures etc..
	183	*/
	184	void exit_thread(void)
	185	{
	186	}
	187
	188	void flush_thread(void)
	189	{
	190	/* Only needs to handle fpu stuff or perf monitors.
	191	** REVISIT: several arches implement a "lazy fpu state".
	192	*/
1da177e4 LT	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. */
803094f4 HD	233	int __user parent_tidptr = (int __user )regs->gr[24];
803094f4 HD	234	int __user child_tidptr = (int __user )regs->gr[22];
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	245	return do_fork(clone_flags, usp, regs, 0, parent_tidptr, child_tidptr);
1da177e4 LT	246	}
	247
	248	int
	249	sys_vfork(struct pt_regs *regs)
	250	{
	251	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, regs->gr[30], regs, 0, NULL, NULL);
	252	}
	253
	254	int
6f2c55b8	255	copy_thread(unsigned long clone_flags, unsigned long usp,
1da177e4 LT	256	unsigned long unused, /* in ia64 this is "user_stack_size" */
	257	struct task_struct * p, struct pt_regs * pregs)
	258	{
	259	struct pt_regs * cregs = &(p->thread.regs);
40f1f0de	260	void *stack = task_stack_page(p);
1da177e4 LT	261
	262	/* We have to use void * instead of a function pointer, because
	263	* function pointers aren't a pointer to the function on 64-bit.
	264	* Make them const so the compiler knows they live in .text */
	265	extern void * const ret_from_kernel_thread;
	266	extern void * const child_return;
	267	#ifdef CONFIG_HPUX
	268	extern void * const hpux_child_return;
	269	#endif
	270
	271	cregs = pregs;
	272
	273	/* Set the return value for the child. Note that this is not
	274	actually restored by the syscall exit path, but we put it
	275	here for consistency in case of signals. */
	276	cregs->gr[28] = 0; /* child */
	277
	278	/*
	279	* We need to differentiate between a user fork and a
	280	* kernel fork. We can't use user_mode, because the
	281	* the syscall path doesn't save iaoq. Right now
	282	* We rely on the fact that kernel_thread passes
	283	* in zero for usp.
	284	*/
	285	if (usp == 1) {
	286	/* kernel thread */
40f1f0de	287	cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN;
1da177e4 LT	288	/* Must exit via ret_from_kernel_thread in order
	289	* to call schedule_tail()
	290	*/
	291	cregs->kpc = (unsigned long) &ret_from_kernel_thread;
	292	/*
	293	* Copy function and argument to be called from
	294	* ret_from_kernel_thread.
	295	*/
a8f44e38	296	#ifdef CONFIG_64BIT
1da177e4 LT	297	cregs->gr[27] = pregs->gr[27];
	298	#endif
	299	cregs->gr[26] = pregs->gr[26];
	300	cregs->gr[25] = pregs->gr[25];
	301	} else {
	302	/* user thread */
	303	/*
	304	* Note that the fork wrappers are responsible
	305	* for setting gr[21].
	306	*/
	307
	308	/* Use same stack depth as parent */
40f1f0de	309	cregs->ksp = (unsigned long)stack
1da177e4 LT	310	+ (pregs->gr[21] & (THREAD_SIZE - 1));
1da177e4 LT	311	cregs->gr[30] = usp;
5b24c421	312	if (personality(p->personality) == PER_HPUX) {
1da177e4 LT	313	#ifdef CONFIG_HPUX
	314	cregs->kpc = (unsigned long) &hpux_child_return;
	315	#else
	316	BUG();
	317	#endif
	318	} else {
	319	cregs->kpc = (unsigned long) &child_return;
	320	}
b2450cc1 CD	321	/* Setup thread TLS area from the 4th parameter in clone */
	322	if (clone_flags & CLONE_SETTLS)
	323	cregs->cr27 = pregs->gr[23];
	324
1da177e4 LT	325	}
	326
	327	return 0;
	328	}
	329
	330	unsigned long thread_saved_pc(struct task_struct *t)
	331	{
	332	return t->thread.regs.kpc;
	333	}
	334
	335	/*
	336	* sys_execve() executes a new program.
	337	*/
	338
	339	asmlinkage int sys_execve(struct pt_regs *regs)
	340	{
	341	int error;
	342	char *filename;
	343
	344	filename = getname((const char __user *) regs->gr[26]);
	345	error = PTR_ERR(filename);
	346	if (IS_ERR(filename))
	347	goto out;
d7627467 DH	348	error = do_execve(filename,
	349	(const char __user const __user ) regs->gr[25],
	350	(const char __user const __user ) regs->gr[24],
	351	regs);
1da177e4 LT	352	putname(filename);
	353	out:
	354
	355	return error;
	356	}
	357
d7627467 DH	358	extern int __execve(const char *filename,
	359	const char *const argv[],
	360	const char const envp[], struct task_struct task);
	361	int kernel_execve(const char *filename,
	362	const char *const argv[],
	363	const char *const envp[])
3db03b4a AB	364	{
	365	return __execve(filename, argv, envp, current);
	366	}
	367
	368	unsigned long
1da177e4 LT	369	get_wchan(struct task_struct *p)
	370	{
	371	struct unwind_frame_info info;
	372	unsigned long ip;
	373	int count = 0;
cc650a7a KM	374
	375	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	376	return 0;
	377
1da177e4 LT	378	/*
	379	* These bracket the sleeping functions..
	380	*/
	381
	382	unwind_frame_init_from_blocked_task(&info, p);
	383	do {
	384	if (unwind_once(&info) < 0)
	385	return 0;
	386	ip = info.ip;
	387	if (!in_sched_functions(ip))
	388	return ip;
	389	} while (count++ < 16);
	390	return 0;
	391	}
b609308e KM	392
	393	#ifdef CONFIG_64BIT
	394	void dereference_function_descriptor(void ptr)
	395	{
	396	Elf64_Fdesc *desc = ptr;
	397	void *p;
	398
	399	if (!probe_kernel_address(&desc->addr, p))
	400	ptr = p;
	401	return ptr;
	402	}
	403	#endif