[thirdparty/kernel/stable.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) 2001-2014 Helge Deller <deller@gmx.de>
 *    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 <linux/rcupdate.h>
#include <linux/random.h>

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

#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);

/*
 * 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;
}

int
copy_thread(unsigned long clone_flags, unsigned long usp,
	    unsigned long arg, struct task_struct *p)
{
	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
	if (unlikely(p->flags & PF_KTHREAD)) {
		memset(cregs, 0, sizeof(struct pt_regs));
		if (!usp) /* idle thread */
			return 0;

		/* kernel thread */
		/* Must exit via ret_from_kernel_thread in order
		 * to call schedule_tail()
		 */
		cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
		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] = ((unsigned long *)usp)[3];
		cregs->gr[26] = ((unsigned long *)usp)[2];
#else
		cregs->gr[26] = usp;
#endif
		cregs->gr[25] = arg;
	} else {
		/* user thread */
		/* 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) */
		if (usp) {
			usp = ALIGN(usp, 4);
			if (likely(usp))
				cregs->gr[30] = usp;
		}
		cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
		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 = cregs->gr[23];
	}

	return 0;
}

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

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

static inline unsigned long brk_rnd(void)
{
	/* 8MB for 32bit, 1GB for 64bit */
	if (is_32bit_task())
		return (get_random_int() & 0x7ffUL) << PAGE_SHIFT;
	else
		return (get_random_int() & 0x3ffffUL) << PAGE_SHIFT;
}

unsigned long arch_randomize_brk(struct mm_struct *mm)
{
	unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());

	if (ret < mm->brk)
		return mm->brk;
	return ret;
}
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>
9dabf60d	16	* Copyright (C) 2001-2014 Helge Deller <deller@gmx.de>
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>
fbe75218	51	#include <linux/rcupdate.h>
9dabf60d	52	#include <linux/random.h>
1da177e4 LT	53
1da177e4 LT	54	#include <asm/io.h>
0013a854	55	#include <asm/asm-offsets.h>
ff0ab8af	56	#include <asm/assembly.h>
1da177e4 LT	57	#include <asm/pdc.h>
	58	#include <asm/pdc_chassis.h>
	59	#include <asm/pgalloc.h>
1da177e4	60	#include <asm/unwind.h>
b609308e	61	#include <asm/sections.h>
1da177e4	62
10992092	63	#define COMMAND_GLOBAL F_EXTEND(0xfffe0030)
1da177e4 LT	64	#define CMD_RESET 5 /* reset any module */
	65
	66	/*
	67	** The Wright Brothers and Gecko systems have a H/W problem
	68	** (Lasi...'nuf said) may cause a broadcast reset to lockup
	69	** the system. An HVERSION dependent PDC call was developed
	70	** to perform a "safe", platform specific broadcast reset instead
	71	** of kludging up all the code.
	72	**
	73	** Older machines which do not implement PDC_BROADCAST_RESET will
	74	** return (with an error) and the regular broadcast reset can be
	75	** issued. Obviously, if the PDC does implement PDC_BROADCAST_RESET
	76	** the PDC call will not return (the system will be reset).
	77	*/
	78	void machine_restart(char *cmd)
	79	{
	80	#ifdef FASTBOOT_SELFTEST_SUPPORT
	81	/*
	82	** If user has modified the Firmware Selftest Bitmap,
	83	** run the tests specified in the bitmap after the
	84	** system is rebooted w/PDC_DO_RESET.
	85	**
	86	** ftc_bitmap = 0x1AUL "Skip destructive memory tests"
	87	**
	88	** Using "directed resets" at each processor with the MEM_TOC
	89	** vector cleared will also avoid running destructive
	90	** memory self tests. (Not implemented yet)
	91	*/
	92	if (ftc_bitmap) {
	93	pdc_do_firm_test_reset(ftc_bitmap);
	94	}
	95	#endif
	96	/* set up a new led state on systems shipped with a LED State panel */
	97	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	98
	99	/* "Normal" system reset */
	100	pdc_do_reset();
	101
	102	/* Nope...box should reset with just CMD_RESET now */
	103	gsc_writel(CMD_RESET, COMMAND_GLOBAL);
	104
	105	/* Wait for RESET to lay us to rest. */
	106	while (1) ;
	107
	108	}
	109
1da177e4 LT	110	void machine_halt(void)
	111	{
	112	/*
	113	** The LED/ChassisCodes are updated by the led_halt()
	114	** function, called by the reboot notifier chain.
	115	*/
	116	}
	117
85509c00	118	void (*chassis_power_off)(void);
1da177e4 LT	119
	120	/*
	121	* This routine is called from sys_reboot to actually turn off the
	122	* machine
	123	*/
	124	void machine_power_off(void)
	125	{
	126	/* If there is a registered power off handler, call it. */
85509c00 KM	127	if (chassis_power_off)
85509c00 KM	128	chassis_power_off();
1da177e4 LT	129
	130	/* Put the soft power button back under hardware control.
	131	* If the user had already pressed the power button, the
	132	* following call will immediately power off. */
	133	pdc_soft_power_button(0);
	134
	135	pdc_chassis_send_status(PDC_CHASSIS_DIRECT_SHUTDOWN);
	136
	137	/* It seems we have no way to power the system off via
	138	* software. The user has to press the button himself. */
	139
	140	printk(KERN_EMERG "System shut down completed.\n"
ad361c98	141	"Please power this system off now.");
1da177e4 LT	142	}
1da177e4 LT	143
85509c00 KM	144	void (*pm_power_off)(void) = machine_power_off;
85509c00 KM	145	EXPORT_SYMBOL(pm_power_off);
1da177e4	146
1da177e4 LT	147	/*
	148	* Free current thread data structures etc..
	149	*/
	150	void exit_thread(void)
	151	{
	152	}
	153
	154	void flush_thread(void)
	155	{
	156	/* Only needs to handle fpu stuff or perf monitors.
	157	** REVISIT: several arches implement a "lazy fpu state".
	158	*/
1da177e4 LT	159	}
	160
	161	void release_thread(struct task_struct *dead_task)
	162	{
	163	}
	164
	165	/*
	166	* Fill in the FPU structure for a core dump.
	167	*/
	168
	169	int dump_fpu (struct pt_regs * regs, elf_fpregset_t *r)
	170	{
	171	if (regs == NULL)
	172	return 0;
	173
	174	memcpy(r, regs->fr, sizeof *r);
	175	return 1;
	176	}
	177
	178	int dump_task_fpu (struct task_struct tsk, elf_fpregset_t r)
	179	{
	180	memcpy(r, tsk->thread.regs.fr, sizeof(*r));
	181	return 1;
	182	}
	183
1da177e4	184	int
6f2c55b8	185	copy_thread(unsigned long clone_flags, unsigned long usp,
afa86fc4	186	unsigned long arg, struct task_struct *p)
1da177e4	187	{
afa86fc4	188	struct pt_regs *cregs = &(p->thread.regs);
40f1f0de	189	void *stack = task_stack_page(p);
1da177e4 LT	190
	191	/* We have to use void * instead of a function pointer, because
	192	* function pointers aren't a pointer to the function on 64-bit.
	193	* Make them const so the compiler knows they live in .text */
	194	extern void * const ret_from_kernel_thread;
	195	extern void * const child_return;
	196	#ifdef CONFIG_HPUX
	197	extern void * const hpux_child_return;
	198	#endif
ff0ab8af	199	if (unlikely(p->flags & PF_KTHREAD)) {
a44e060f	200	memset(cregs, 0, sizeof(struct pt_regs));
ff0ab8af AV	201	if (!usp) /* idle thread */
	202	return 0;
	203
1da177e4	204	/* kernel thread */
1da177e4 LT	205	/* Must exit via ret_from_kernel_thread in order
	206	* to call schedule_tail()
	207	*/
ff0ab8af	208	cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
1da177e4 LT	209	cregs->kpc = (unsigned long) &ret_from_kernel_thread;
	210	/*
	211	* Copy function and argument to be called from
	212	* ret_from_kernel_thread.
	213	*/
a8f44e38	214	#ifdef CONFIG_64BIT
a44e060f AV	215	cregs->gr[27] = ((unsigned long *)usp)[3];
	216	cregs->gr[26] = ((unsigned long *)usp)[2];
	217	#else
	218	cregs->gr[26] = usp;
1da177e4	219	#endif
a44e060f	220	cregs->gr[25] = arg;
1da177e4 LT	221	} else {
1da177e4 LT	222	/* user thread */
415bfae9 AV	223	/* usp must be word aligned. This also prevents users from
	224	* passing in the value 1 (which is the signal for a special
	225	* return for a kernel thread) */
	226	if (usp) {
	227	usp = ALIGN(usp, 4);
	228	if (likely(usp))
	229	cregs->gr[30] = usp;
	230	}
ff0ab8af	231	cregs->ksp = (unsigned long)stack + THREAD_SZ_ALGN + FRAME_SIZE;
5b24c421	232	if (personality(p->personality) == PER_HPUX) {
1da177e4 LT	233	#ifdef CONFIG_HPUX
	234	cregs->kpc = (unsigned long) &hpux_child_return;
	235	#else
	236	BUG();
	237	#endif
	238	} else {
	239	cregs->kpc = (unsigned long) &child_return;
	240	}
b2450cc1 CD	241	/* Setup thread TLS area from the 4th parameter in clone */
b2450cc1 CD	242	if (clone_flags & CLONE_SETTLS)
415bfae9	243	cregs->cr27 = cregs->gr[23];
1da177e4 LT	244	}
	245
	246	return 0;
	247	}
	248
	249	unsigned long thread_saved_pc(struct task_struct *t)
	250	{
	251	return t->thread.regs.kpc;
	252	}
	253
3db03b4a	254	unsigned long
1da177e4 LT	255	get_wchan(struct task_struct *p)
	256	{
	257	struct unwind_frame_info info;
	258	unsigned long ip;
	259	int count = 0;
cc650a7a KM	260
	261	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	262	return 0;
	263
1da177e4 LT	264	/*
	265	* These bracket the sleeping functions..
	266	*/
	267
	268	unwind_frame_init_from_blocked_task(&info, p);
	269	do {
	270	if (unwind_once(&info) < 0)
	271	return 0;
	272	ip = info.ip;
	273	if (!in_sched_functions(ip))
	274	return ip;
	275	} while (count++ < 16);
	276	return 0;
	277	}
b609308e KM	278
	279	#ifdef CONFIG_64BIT
	280	void dereference_function_descriptor(void ptr)
	281	{
	282	Elf64_Fdesc *desc = ptr;
	283	void *p;
	284
	285	if (!probe_kernel_address(&desc->addr, p))
	286	ptr = p;
	287	return ptr;
	288	}
	289	#endif
9dabf60d HD	290
	291	static inline unsigned long brk_rnd(void)
	292	{
	293	/* 8MB for 32bit, 1GB for 64bit */
	294	if (is_32bit_task())
	295	return (get_random_int() & 0x7ffUL) << PAGE_SHIFT;
	296	else
	297	return (get_random_int() & 0x3ffffUL) << PAGE_SHIFT;
	298	}
	299
	300	unsigned long arch_randomize_brk(struct mm_struct *mm)
	301	{
	302	unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
	303
	304	if (ret < mm->brk)
	305	return mm->brk;
	306	return ret;
	307	}