[linux-block.git] / arch / unicore32 / kernel / process.c

/*
 * linux/arch/unicore32/kernel/process.c
 *
 * Code specific to PKUnity SoC and UniCore ISA
 *
 * Copyright (C) 2001-2010 GUAN Xue-tao
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <stdarg.h>

#include <linux/module.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/interrupt.h>
#include <linux/kallsyms.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/elfcore.h>
#include <linux/pm.h>
#include <linux/tick.h>
#include <linux/utsname.h>
#include <linux/uaccess.h>
#include <linux/random.h>
#include <linux/gpio.h>
#include <linux/stacktrace.h>

#include <asm/cacheflush.h>
#include <asm/processor.h>
#include <asm/stacktrace.h>

#include "setup.h"

static const char * const processor_modes[] = {
	"UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
	"UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
	"USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
	"UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
};

void arch_cpu_idle(void)
{
	cpu_do_idle();
	local_irq_enable();
}

void machine_halt(void)
{
	gpio_set_value(GPO_SOFT_OFF, 0);
}

/*
 * Function pointers to optional machine specific functions
 */
void (*pm_power_off)(void) = NULL;
EXPORT_SYMBOL(pm_power_off);

void machine_power_off(void)
{
	if (pm_power_off)
		pm_power_off();
	machine_halt();
}

void machine_restart(char *cmd)
{
	/* Disable interrupts first */
	local_irq_disable();

	/*
	 * Tell the mm system that we are going to reboot -
	 * we may need it to insert some 1:1 mappings so that
	 * soft boot works.
	 */
	setup_mm_for_reboot();

	/* Clean and invalidate caches */
	flush_cache_all();

	/* Turn off caching */
	cpu_proc_fin();

	/* Push out any further dirty data, and ensure cache is empty */
	flush_cache_all();

	/*
	 * Now handle reboot code.
	 */
	if (reboot_mode == REBOOT_SOFT) {
		/* Jump into ROM at address 0xffff0000 */
		cpu_reset(VECTORS_BASE);
	} else {
		writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
		writel(0x00100800, PM_PLLDDRCFG); /* ddr clk =  44M */
		writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */

		/* Use on-chip reset capability */
		/* following instructions must be in one icache line */
		__asm__ __volatile__(
			"	.align 5\n\t"
			"	stw	%1, [%0]\n\t"
			"201:	ldw	r0, [%0]\n\t"
			"	cmpsub.a	r0, #0\n\t"
			"	bne	201b\n\t"
			"	stw	%3, [%2]\n\t"
			"	nop; nop; nop\n\t"
			/* prefetch 3 instructions at most */
			:
			: "r" (PM_PMCR),
			  "r" (PM_PMCR_CFBSYS | PM_PMCR_CFBDDR
				| PM_PMCR_CFBVGA),
			  "r" (RESETC_SWRR),
			  "r" (RESETC_SWRR_SRB)
			: "r0", "memory");
	}

	/*
	 * Whoops - the architecture was unable to reboot.
	 * Tell the user!
	 */
	mdelay(1000);
	printk(KERN_EMERG "Reboot failed -- System halted\n");
	do { } while (1);
}

void __show_regs(struct pt_regs *regs)
{
	unsigned long flags;
	char buf[64];

	show_regs_print_info(KERN_DEFAULT);
	print_symbol("PC is at %s\n", instruction_pointer(regs));
	print_symbol("LR is at %s\n", regs->UCreg_lr);
	printk(KERN_DEFAULT "pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
		regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
		regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
	printk(KERN_DEFAULT "r26: %08lx  r25: %08lx  r24: %08lx\n",
		regs->UCreg_26, regs->UCreg_25,
		regs->UCreg_24);
	printk(KERN_DEFAULT "r23: %08lx  r22: %08lx  r21: %08lx  r20: %08lx\n",
		regs->UCreg_23, regs->UCreg_22,
		regs->UCreg_21, regs->UCreg_20);
	printk(KERN_DEFAULT "r19: %08lx  r18: %08lx  r17: %08lx  r16: %08lx\n",
		regs->UCreg_19, regs->UCreg_18,
		regs->UCreg_17, regs->UCreg_16);
	printk(KERN_DEFAULT "r15: %08lx  r14: %08lx  r13: %08lx  r12: %08lx\n",
		regs->UCreg_15, regs->UCreg_14,
		regs->UCreg_13, regs->UCreg_12);
	printk(KERN_DEFAULT "r11: %08lx  r10: %08lx  r9 : %08lx  r8 : %08lx\n",
		regs->UCreg_11, regs->UCreg_10,
		regs->UCreg_09, regs->UCreg_08);
	printk(KERN_DEFAULT "r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
		regs->UCreg_07, regs->UCreg_06,
		regs->UCreg_05, regs->UCreg_04);
	printk(KERN_DEFAULT "r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
		regs->UCreg_03, regs->UCreg_02,
		regs->UCreg_01, regs->UCreg_00);

	flags = regs->UCreg_asr;
	buf[0] = flags & PSR_S_BIT ? 'S' : 's';
	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	buf[4] = '\0';

	printk(KERN_DEFAULT "Flags: %s  INTR o%s  REAL o%s  Mode %s  Segment %s\n",
		buf, interrupts_enabled(regs) ? "n" : "ff",
		fast_interrupts_enabled(regs) ? "n" : "ff",
		processor_modes[processor_mode(regs)],
		segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
	{
		unsigned int ctrl;

		buf[0] = '\0';
		{
			unsigned int transbase;
			asm("movc %0, p0.c2, #0\n"
			    : "=r" (transbase));
			snprintf(buf, sizeof(buf), "  Table: %08x", transbase);
		}
		asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));

		printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
	}
}

void show_regs(struct pt_regs *regs)
{
	printk(KERN_DEFAULT "\n");
	printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
			task_pid_nr(current), current->comm);
	__show_regs(regs);
	__backtrace();
}

void flush_thread(void)
{
	struct thread_info *thread = current_thread_info();
	struct task_struct *tsk = current;

	memset(thread->used_cp, 0, sizeof(thread->used_cp));
	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
#ifdef CONFIG_UNICORE_FPU_F64
	memset(&thread->fpstate, 0, sizeof(struct fp_state));
#endif
}

void release_thread(struct task_struct *dead_task)
{
}

asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
asmlinkage void ret_from_kernel_thread(void) __asm__("ret_from_kernel_thread");

int
copy_thread(unsigned long clone_flags, unsigned long stack_start,
	    unsigned long stk_sz, struct task_struct *p)
{
	struct thread_info *thread = task_thread_info(p);
	struct pt_regs *childregs = task_pt_regs(p);

	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
	thread->cpu_context.sp = (unsigned long)childregs;
	if (unlikely(p->flags & PF_KTHREAD)) {
		thread->cpu_context.pc = (unsigned long)ret_from_kernel_thread;
		thread->cpu_context.r4 = stack_start;
		thread->cpu_context.r5 = stk_sz;
		memset(childregs, 0, sizeof(struct pt_regs));
	} else {
		thread->cpu_context.pc = (unsigned long)ret_from_fork;
		*childregs = *current_pt_regs();
		childregs->UCreg_00 = 0;
		if (stack_start)
			childregs->UCreg_sp = stack_start;

		if (clone_flags & CLONE_SETTLS)
			childregs->UCreg_16 = childregs->UCreg_03;
	}
	return 0;
}

/*
 * Fill in the task's elfregs structure for a core dump.
 */
int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
{
	elf_core_copy_regs(elfregs, task_pt_regs(t));
	return 1;
}

/*
 * fill in the fpe structure for a core dump...
 */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fp)
{
	struct thread_info *thread = current_thread_info();
	int used_math = thread->used_cp[1] | thread->used_cp[2];

#ifdef CONFIG_UNICORE_FPU_F64
	if (used_math)
		memcpy(fp, &thread->fpstate, sizeof(*fp));
#endif
	return used_math != 0;
}
EXPORT_SYMBOL(dump_fpu);

unsigned long get_wchan(struct task_struct *p)
{
	struct stackframe frame;
	int count = 0;
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	frame.fp = thread_saved_fp(p);
	frame.sp = thread_saved_sp(p);
	frame.lr = 0;			/* recovered from the stack */
	frame.pc = thread_saved_pc(p);
	do {
		int ret = unwind_frame(&frame);
		if (ret < 0)
			return 0;
		if (!in_sched_functions(frame.pc))
			return frame.pc;
	} while ((count++) < 16);
	return 0;
}

unsigned long arch_randomize_brk(struct mm_struct *mm)
{
	return randomize_page(mm->brk, 0x02000000);
}

/*
 * The vectors page is always readable from user space for the
 * atomic helpers and the signal restart code.  Let's declare a mapping
 * for it so it is visible through ptrace and /proc/<pid>/mem.
 */

int vectors_user_mapping(void)
{
	struct mm_struct *mm = current->mm;
	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
				       VM_READ | VM_EXEC |
				       VM_MAYREAD | VM_MAYEXEC |
				       VM_DONTEXPAND | VM_DONTDUMP,
				       NULL);
}

const char *arch_vma_name(struct vm_area_struct *vma)
{
	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
}
Commit	Line	Data
f73670e8 G	1	/*
	2	* linux/arch/unicore32/kernel/process.c
	3	*
	4	* Code specific to PKUnity SoC and UniCore ISA
	5	*
	6	* Copyright (C) 2001-2010 GUAN Xue-tao
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12	#include <stdarg.h>
	13
	14	#include <linux/module.h>
	15	#include <linux/sched.h>
b17b0153	16	#include <linux/sched/debug.h>
29930025	17	#include <linux/sched/task.h>
68db0cf1	18	#include <linux/sched/task_stack.h>
f73670e8 G	19	#include <linux/kernel.h>
	20	#include <linux/mm.h>
	21	#include <linux/stddef.h>
	22	#include <linux/unistd.h>
	23	#include <linux/delay.h>
	24	#include <linux/reboot.h>
	25	#include <linux/interrupt.h>
	26	#include <linux/kallsyms.h>
	27	#include <linux/init.h>
	28	#include <linux/cpu.h>
	29	#include <linux/elfcore.h>
	30	#include <linux/pm.h>
	31	#include <linux/tick.h>
	32	#include <linux/utsname.h>
	33	#include <linux/uaccess.h>
	34	#include <linux/random.h>
	35	#include <linux/gpio.h>
	36	#include <linux/stacktrace.h>
	37
	38	#include <asm/cacheflush.h>
	39	#include <asm/processor.h>
f73670e8 G	40	#include <asm/stacktrace.h>
	41
	42	#include "setup.h"
	43
	44	static const char * const processor_modes[] = {
	45	"UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
	46	"UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
	47	"USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
	48	"UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
	49	};
	50
aba92c9e	51	void arch_cpu_idle(void)
f73670e8	52	{
aba92c9e TG	53	cpu_do_idle();
aba92c9e TG	54	local_irq_enable();
f73670e8 G	55	}
f73670e8 G	56
f73670e8 G	57	void machine_halt(void)
	58	{
	59	gpio_set_value(GPO_SOFT_OFF, 0);
	60	}
	61
	62	/*
	63	* Function pointers to optional machine specific functions
	64	*/
	65	void (*pm_power_off)(void) = NULL;
3420d49d	66	EXPORT_SYMBOL(pm_power_off);
f73670e8 G	67
	68	void machine_power_off(void)
	69	{
	70	if (pm_power_off)
	71	pm_power_off();
	72	machine_halt();
	73	}
	74
	75	void machine_restart(char *cmd)
	76	{
	77	/* Disable interrupts first */
	78	local_irq_disable();
	79
	80	/*
	81	* Tell the mm system that we are going to reboot -
	82	* we may need it to insert some 1:1 mappings so that
	83	* soft boot works.
	84	*/
c97a7008	85	setup_mm_for_reboot();
f73670e8 G	86
	87	/* Clean and invalidate caches */
	88	flush_cache_all();
	89
	90	/* Turn off caching */
	91	cpu_proc_fin();
	92
	93	/* Push out any further dirty data, and ensure cache is empty */
	94	flush_cache_all();
	95
	96	/*
	97	* Now handle reboot code.
	98	*/
c97a7008	99	if (reboot_mode == REBOOT_SOFT) {
f73670e8 G	100	/* Jump into ROM at address 0xffff0000 */
	101	cpu_reset(VECTORS_BASE);
	102	} else {
e5abf78b G	103	writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
	104	writel(0x00100800, PM_PLLDDRCFG); /* ddr clk = 44M */
	105	writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */
f73670e8 G	106
	107	/* Use on-chip reset capability */
	108	/* following instructions must be in one icache line */
	109	__asm__ __volatile__(
	110	" .align 5\n\t"
	111	" stw %1, [%0]\n\t"
	112	"201: ldw r0, [%0]\n\t"
	113	" cmpsub.a r0, #0\n\t"
	114	" bne 201b\n\t"
	115	" stw %3, [%2]\n\t"
	116	" nop; nop; nop\n\t"
	117	/* prefetch 3 instructions at most */
	118	:
e5abf78b	119	: "r" (PM_PMCR),
f73670e8 G	120	"r" (PM_PMCR_CFBSYS \| PM_PMCR_CFBDDR
f73670e8 G	121	\| PM_PMCR_CFBVGA),
e5abf78b	122	"r" (RESETC_SWRR),
f73670e8 G	123	"r" (RESETC_SWRR_SRB)
	124	: "r0", "memory");
	125	}
	126
	127	/*
	128	* Whoops - the architecture was unable to reboot.
	129	* Tell the user!
	130	*/
	131	mdelay(1000);
	132	printk(KERN_EMERG "Reboot failed -- System halted\n");
	133	do { } while (1);
	134	}
	135
	136	void __show_regs(struct pt_regs *regs)
	137	{
	138	unsigned long flags;
	139	char buf[64];
	140
a43cb95d	141	show_regs_print_info(KERN_DEFAULT);
f73670e8 G	142	print_symbol("PC is at %s\n", instruction_pointer(regs));
	143	print_symbol("LR is at %s\n", regs->UCreg_lr);
	144	printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
	145	"sp : %08lx ip : %08lx fp : %08lx\n",
	146	regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
	147	regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
	148	printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n",
	149	regs->UCreg_26, regs->UCreg_25,
	150	regs->UCreg_24);
	151	printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
	152	regs->UCreg_23, regs->UCreg_22,
	153	regs->UCreg_21, regs->UCreg_20);
	154	printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
	155	regs->UCreg_19, regs->UCreg_18,
	156	regs->UCreg_17, regs->UCreg_16);
	157	printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
	158	regs->UCreg_15, regs->UCreg_14,
	159	regs->UCreg_13, regs->UCreg_12);
	160	printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
	161	regs->UCreg_11, regs->UCreg_10,
	162	regs->UCreg_09, regs->UCreg_08);
	163	printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	164	regs->UCreg_07, regs->UCreg_06,
	165	regs->UCreg_05, regs->UCreg_04);
	166	printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	167	regs->UCreg_03, regs->UCreg_02,
	168	regs->UCreg_01, regs->UCreg_00);
	169
	170	flags = regs->UCreg_asr;
	171	buf[0] = flags & PSR_S_BIT ? 'S' : 's';
	172	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	173	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	174	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	175	buf[4] = '\0';
	176
	177	printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n",
	178	buf, interrupts_enabled(regs) ? "n" : "ff",
	179	fast_interrupts_enabled(regs) ? "n" : "ff",
	180	processor_modes[processor_mode(regs)],
	181	segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
	182	{
	183	unsigned int ctrl;
	184
	185	buf[0] = '\0';
	186	{
	187	unsigned int transbase;
	188	asm("movc %0, p0.c2, #0\n"
	189	: "=r" (transbase));
	190	snprintf(buf, sizeof(buf), " Table: %08x", transbase);
	191	}
	192	asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));
	193
	194	printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
	195	}
	196	}
	197
	198	void show_regs(struct pt_regs *regs)
	199	{
	200	printk(KERN_DEFAULT "\n");
	201	printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
	202	task_pid_nr(current), current->comm);
	203	__show_regs(regs);
	204	__backtrace();
	205	}
206
f73670e8 G	207	void flush_thread(void)
	208	{
	209	struct thread_info *thread = current_thread_info();
	210	struct task_struct *tsk = current;
	211
	212	memset(thread->used_cp, 0, sizeof(thread->used_cp));
	213	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
	214	#ifdef CONFIG_UNICORE_FPU_F64
	215	memset(&thread->fpstate, 0, sizeof(struct fp_state));
	216	#endif
	217	}
	218
	219	void release_thread(struct task_struct *dead_task)
	220	{
	221	}
	222
	223	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
38e99353	224	asmlinkage void ret_from_kernel_thread(void) __asm__("ret_from_kernel_thread");
f73670e8 G	225
	226	int
	227	copy_thread(unsigned long clone_flags, unsigned long stack_start,
afa86fc4	228	unsigned long stk_sz, struct task_struct *p)
f73670e8 G	229	{
	230	struct thread_info *thread = task_thread_info(p);
	231	struct pt_regs *childregs = task_pt_regs(p);
	232
f73670e8 G	233	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
f73670e8 G	234	thread->cpu_context.sp = (unsigned long)childregs;
cb562173	235	if (unlikely(p->flags & PF_KTHREAD)) {
38e99353 AV	236	thread->cpu_context.pc = (unsigned long)ret_from_kernel_thread;
	237	thread->cpu_context.r4 = stack_start;
	238	thread->cpu_context.r5 = stk_sz;
	239	memset(childregs, 0, sizeof(struct pt_regs));
	240	} else {
	241	thread->cpu_context.pc = (unsigned long)ret_from_fork;
cb562173	242	childregs = current_pt_regs();
38e99353	243	childregs->UCreg_00 = 0;
cb562173 AV	244	if (stack_start)
cb562173 AV	245	childregs->UCreg_sp = stack_start;
f73670e8	246
38e99353	247	if (clone_flags & CLONE_SETTLS)
cb562173	248	childregs->UCreg_16 = childregs->UCreg_03;
38e99353	249	}
f73670e8 G	250	return 0;
	251	}
	252
	253	/*
	254	* Fill in the task's elfregs structure for a core dump.
	255	*/
	256	int dump_task_regs(struct task_struct t, elf_gregset_t elfregs)
	257	{
	258	elf_core_copy_regs(elfregs, task_pt_regs(t));
	259	return 1;
	260	}
	261
	262	/*
	263	* fill in the fpe structure for a core dump...
	264	*/
	265	int dump_fpu(struct pt_regs regs, elf_fpregset_t fp)
	266	{
	267	struct thread_info *thread = current_thread_info();
	268	int used_math = thread->used_cp[1] \| thread->used_cp[2];
	269
	270	#ifdef CONFIG_UNICORE_FPU_F64
	271	if (used_math)
	272	memcpy(fp, &thread->fpstate, sizeof(*fp));
	273	#endif
	274	return used_math != 0;
	275	}
	276	EXPORT_SYMBOL(dump_fpu);
	277
f73670e8 G	278	unsigned long get_wchan(struct task_struct *p)
	279	{
	280	struct stackframe frame;
	281	int count = 0;
	282	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	283	return 0;
	284
	285	frame.fp = thread_saved_fp(p);
	286	frame.sp = thread_saved_sp(p);
	287	frame.lr = 0; /* recovered from the stack */
	288	frame.pc = thread_saved_pc(p);
	289	do {
	290	int ret = unwind_frame(&frame);
	291	if (ret < 0)
	292	return 0;
	293	if (!in_sched_functions(frame.pc))
	294	return frame.pc;
	295	} while ((count++) < 16);
	296	return 0;
	297	}
	298
	299	unsigned long arch_randomize_brk(struct mm_struct *mm)
	300	{
05c2679e	301	return randomize_page(mm->brk, 0x02000000);
f73670e8 G	302	}
	303
	304	/*
	305	* The vectors page is always readable from user space for the
	306	* atomic helpers and the signal restart code. Let's declare a mapping
	307	* for it so it is visible through ptrace and /proc/<pid>/mem.
	308	*/
	309
	310	int vectors_user_mapping(void)
	311	{
	312	struct mm_struct *mm = current->mm;
	313	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
	314	VM_READ \| VM_EXEC \|
	315	VM_MAYREAD \| VM_MAYEXEC \|
314e51b9	316	VM_DONTEXPAND \| VM_DONTDUMP,
f73670e8 G	317	NULL);
	318	}
	319
	320	const char arch_vma_name(struct vm_area_struct vma)
	321	{
	322	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
	323	}