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-rw-r--r--arch/avr32/kernel/process.c67
1 files changed, 17 insertions, 50 deletions
diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c
index 1bb0a8a..07380c3 100644
--- a/arch/avr32/kernel/process.c
+++ b/arch/avr32/kernel/process.c
@@ -69,44 +69,6 @@ void machine_restart(char *cmd)
}
/*
- * PC is actually discarded when returning from a system call -- the
- * return address must be stored in LR. This function will make sure
- * LR points to do_exit before starting the thread.
- *
- * Also, when returning from fork(), r12 is 0, so we must copy the
- * argument as well.
- *
- * r0 : The argument to the main thread function
- * r1 : The address of do_exit
- * r2 : The address of the main thread function
- */
-asmlinkage extern void kernel_thread_helper(void);
-__asm__(" .type kernel_thread_helper, @function\n"
- "kernel_thread_helper:\n"
- " mov r12, r0\n"
- " mov lr, r2\n"
- " mov pc, r1\n"
- " .size kernel_thread_helper, . - kernel_thread_helper");
-
-int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
-{
- struct pt_regs regs;
-
- memset(&regs, 0, sizeof(regs));
-
- regs.r0 = (unsigned long)arg;
- regs.r1 = (unsigned long)fn;
- regs.r2 = (unsigned long)do_exit;
- regs.lr = (unsigned long)kernel_thread_helper;
- regs.pc = (unsigned long)kernel_thread_helper;
- regs.sr = MODE_SUPERVISOR;
-
- return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
- 0, &regs, 0, NULL, NULL);
-}
-EXPORT_SYMBOL(kernel_thread);
-
-/*
* Free current thread data structures etc
*/
void exit_thread(void)
@@ -332,26 +294,31 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
}
asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
+asmlinkage void syscall_return(void);
int copy_thread(unsigned long clone_flags, unsigned long usp,
- unsigned long unused,
+ unsigned long arg,
struct task_struct *p, struct pt_regs *regs)
{
- struct pt_regs *childregs;
-
- childregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long)task_stack_page(p))) - 1;
- *childregs = *regs;
-
- if (user_mode(regs))
+ struct pt_regs *childregs = task_pt_regs(p);
+
+ if (unlikely(!regs)) {
+ memset(childregs, 0, sizeof(struct pt_regs));
+ p->thread.cpu_context.r0 = arg;
+ p->thread.cpu_context.r1 = usp; /* fn */
+ p->thread.cpu_context.r2 = syscall_return;
+ p->thread.cpu_context.pc = (unsigned long)ret_from_kernel_thread;
+ childregs->sr = MODE_SUPERVISOR;
+ } else {
+ *childregs = *regs;
childregs->sp = usp;
- else
- childregs->sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
-
- childregs->r12 = 0; /* Set return value for child */
+ childregs->r12 = 0; /* Set return value for child */
+ p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
+ }
p->thread.cpu_context.sr = MODE_SUPERVISOR | SR_GM;
p->thread.cpu_context.ksp = (unsigned long)childregs;
- p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
clear_tsk_thread_flag(p, TIF_DEBUG);
if ((clone_flags & CLONE_PTRACE) && test_thread_flag(TIF_DEBUG))
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