linux/arch/h8300/kernel/process.c
David Howells d7627467b7 Make do_execve() take a const filename pointer
Make do_execve() take a const filename pointer so that kernel_execve() compiles
correctly on ARM:

arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type

This also requires the argv and envp arguments to be consted twice, once for
the pointer array and once for the strings the array points to.  This is
because do_execve() passes a pointer to the filename (now const) to
copy_strings_kernel().  A simpler alternative would be to cast the filename
pointer in do_execve() when it's passed to copy_strings_kernel().

do_execve() may not change any of the strings it is passed as part of the argv
or envp lists as they are some of them in .rodata, so marking these strings as
const should be fine.

Further kernel_execve() and sys_execve() need to be changed to match.

This has been test built on x86_64, frv, arm and mips.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-17 18:07:43 -07:00

258 lines
5.3 KiB
C

/*
* linux/arch/h8300/kernel/process.c
*
* Yoshinori Sato <ysato@users.sourceforge.jp>
*
* Based on:
*
* linux/arch/m68knommu/kernel/process.c
*
* Copyright (C) 1998 D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
* Kenneth Albanowski <kjahds@kjahds.com>,
* The Silver Hammer Group, Ltd.
*
* linux/arch/m68k/kernel/process.c
*
* Copyright (C) 1995 Hamish Macdonald
*
* 68060 fixes by Jesper Skov
*/
/*
* This file handles the architecture-dependent parts of process handling..
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/traps.h>
#include <asm/setup.h>
#include <asm/pgtable.h>
void (*pm_power_off)(void) = NULL;
EXPORT_SYMBOL(pm_power_off);
asmlinkage void ret_from_fork(void);
/*
* The idle loop on an H8/300..
*/
#if !defined(CONFIG_H8300H_SIM) && !defined(CONFIG_H8S_SIM)
static void default_idle(void)
{
local_irq_disable();
if (!need_resched()) {
local_irq_enable();
/* XXX: race here! What if need_resched() gets set now? */
__asm__("sleep");
} else
local_irq_enable();
}
#else
static void default_idle(void)
{
cpu_relax();
}
#endif
void (*idle)(void) = default_idle;
/*
* 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)
{
while (1) {
while (!need_resched())
idle();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
void machine_restart(char * __unused)
{
local_irq_disable();
__asm__("jmp @@0");
}
void machine_halt(void)
{
local_irq_disable();
__asm__("sleep");
for (;;);
}
void machine_power_off(void)
{
local_irq_disable();
__asm__("sleep");
for (;;);
}
void show_regs(struct pt_regs * regs)
{
printk("\nPC: %08lx Status: %02x",
regs->pc, regs->ccr);
printk("\nORIG_ER0: %08lx ER0: %08lx ER1: %08lx",
regs->orig_er0, regs->er0, regs->er1);
printk("\nER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx",
regs->er2, regs->er3, regs->er4, regs->er5);
printk("\nER6' %08lx ",regs->er6);
if (user_mode(regs))
printk("USP: %08lx\n", rdusp());
else
printk("\n");
}
/*
* Create a kernel thread
*/
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
long retval;
long clone_arg;
mm_segment_t fs;
fs = get_fs();
set_fs (KERNEL_DS);
clone_arg = flags | CLONE_VM;
__asm__("mov.l sp,er3\n\t"
"sub.l er2,er2\n\t"
"mov.l %2,er1\n\t"
"mov.l %1,er0\n\t"
"trapa #0\n\t"
"cmp.l sp,er3\n\t"
"beq 1f\n\t"
"mov.l %4,er0\n\t"
"mov.l %3,er1\n\t"
"jsr @er1\n\t"
"mov.l %5,er0\n\t"
"trapa #0\n"
"1:\n\t"
"mov.l er0,%0"
:"=r"(retval)
:"i"(__NR_clone),"g"(clone_arg),"g"(fn),"g"(arg),"i"(__NR_exit)
:"er0","er1","er2","er3");
set_fs (fs);
return retval;
}
void flush_thread(void)
{
}
/*
* "h8300_fork()".. By the time we get here, the
* non-volatile registers have also been saved on the
* stack. We do some ugly pointer stuff here.. (see
* also copy_thread)
*/
asmlinkage int h8300_fork(struct pt_regs *regs)
{
return -EINVAL;
}
asmlinkage int h8300_vfork(struct pt_regs *regs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, NULL, NULL);
}
asmlinkage int h8300_clone(struct pt_regs *regs)
{
unsigned long clone_flags;
unsigned long newsp;
/* syscall2 puts clone_flags in er1 and usp in er2 */
clone_flags = regs->er1;
newsp = regs->er2;
if (!newsp)
newsp = rdusp();
return do_fork(clone_flags, newsp, regs, 0, NULL, NULL);
}
int copy_thread(unsigned long clone_flags,
unsigned long usp, unsigned long topstk,
struct task_struct * p, struct pt_regs * regs)
{
struct pt_regs * childregs;
childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
*childregs = *regs;
childregs->retpc = (unsigned long) ret_from_fork;
childregs->er0 = 0;
p->thread.usp = usp;
p->thread.ksp = (unsigned long)childregs;
return 0;
}
/*
* sys_execve() executes a new program.
*/
asmlinkage int sys_execve(const char *name,
const char *const *argv,
const char *const *envp,
int dummy, ...)
{
int error;
char * filename;
struct pt_regs *regs = (struct pt_regs *) ((unsigned char *)&dummy-4);
filename = getname(name);
error = PTR_ERR(filename);
if (IS_ERR(filename))
return error;
error = do_execve(filename, argv, envp, regs);
putname(filename);
return error;
}
unsigned long thread_saved_pc(struct task_struct *tsk)
{
return ((struct pt_regs *)tsk->thread.esp0)->pc;
}
unsigned long get_wchan(struct task_struct *p)
{
unsigned long fp, pc;
unsigned long stack_page;
int count = 0;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
stack_page = (unsigned long)p;
fp = ((struct pt_regs *)p->thread.ksp)->er6;
do {
if (fp < stack_page+sizeof(struct thread_info) ||
fp >= 8184+stack_page)
return 0;
pc = ((unsigned long *)fp)[1];
if (!in_sched_functions(pc))
return pc;
fp = *(unsigned long *) fp;
} while (count++ < 16);
return 0;
}