sparc32: switch to generic kernel_thread()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/sparc/kernel/process_32.c b/arch/sparc/kernel/process_32.c
index 487bffb..7276435 100644
--- a/arch/sparc/kernel/process_32.c
+++ b/arch/sparc/kernel/process_32.c
@@ -316,9 +316,10 @@
* XXX See comment above sys_vfork in sparc64. todo.
*/
extern void ret_from_fork(void);
+extern void ret_from_kernel_thread(void);
int copy_thread(unsigned long clone_flags, unsigned long sp,
- unsigned long unused,
+ unsigned long arg,
struct task_struct *p, struct pt_regs *regs)
{
struct thread_info *ti = task_thread_info(p);
@@ -336,16 +337,13 @@
}
/*
- * p->thread_info new_stack childregs
- * ! ! ! {if(PSR_PS) }
- * V V (stk.fr.) V (pt_regs) { (stk.fr.) }
- * +----- - - - - - ------+===========+============={+==========}+
+ * p->thread_info new_stack childregs stack bottom
+ * ! ! ! !
+ * V V (stk.fr.) V (pt_regs) V
+ * +----- - - - - - ------+===========+=============+
*/
new_stack = task_stack_page(p) + THREAD_SIZE;
- if (regs->psr & PSR_PS)
- new_stack -= STACKFRAME_SZ;
new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
- memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
/*
@@ -356,55 +354,58 @@
* Thus, kpsr|=PSR_PIL.
*/
ti->ksp = (unsigned long) new_stack;
+ p->thread.kregs = childregs;
+
+ if (unlikely(p->flags & PF_KTHREAD)) {
+ extern int nwindows;
+ unsigned long psr;
+ memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
+ p->thread.flags |= SPARC_FLAG_KTHREAD;
+ p->thread.current_ds = KERNEL_DS;
+ ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
+ childregs->u_regs[UREG_G1] = sp; /* function */
+ childregs->u_regs[UREG_G2] = arg;
+ psr = childregs->psr = get_psr();
+ ti->kpsr = psr | PSR_PIL;
+ ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
+ return 0;
+ }
+ memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
+ childregs->u_regs[UREG_FP] = sp;
+ p->thread.flags &= ~SPARC_FLAG_KTHREAD;
+ p->thread.current_ds = USER_DS;
ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
ti->kwim = current->thread.fork_kwim;
- if(regs->psr & PSR_PS) {
- extern struct pt_regs fake_swapper_regs;
+ if (sp != regs->u_regs[UREG_FP]) {
+ struct sparc_stackf __user *childstack;
+ struct sparc_stackf __user *parentstack;
- p->thread.kregs = &fake_swapper_regs;
- new_stack += STACKFRAME_SZ + TRACEREG_SZ;
- childregs->u_regs[UREG_FP] = (unsigned long) new_stack;
- p->thread.flags |= SPARC_FLAG_KTHREAD;
- p->thread.current_ds = KERNEL_DS;
- memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);
- childregs->u_regs[UREG_G6] = (unsigned long) ti;
- } else {
- p->thread.kregs = childregs;
- childregs->u_regs[UREG_FP] = sp;
- p->thread.flags &= ~SPARC_FLAG_KTHREAD;
- p->thread.current_ds = USER_DS;
-
- if (sp != regs->u_regs[UREG_FP]) {
- struct sparc_stackf __user *childstack;
- struct sparc_stackf __user *parentstack;
-
- /*
- * This is a clone() call with supplied user stack.
- * Set some valid stack frames to give to the child.
- */
- childstack = (struct sparc_stackf __user *)
- (sp & ~0xfUL);
- parentstack = (struct sparc_stackf __user *)
- regs->u_regs[UREG_FP];
+ /*
+ * This is a clone() call with supplied user stack.
+ * Set some valid stack frames to give to the child.
+ */
+ childstack = (struct sparc_stackf __user *)
+ (sp & ~0xfUL);
+ parentstack = (struct sparc_stackf __user *)
+ regs->u_regs[UREG_FP];
#if 0
- printk("clone: parent stack:\n");
- show_stackframe(parentstack);
+ printk("clone: parent stack:\n");
+ show_stackframe(parentstack);
#endif
- childstack = clone_stackframe(childstack, parentstack);
- if (!childstack)
- return -EFAULT;
+ childstack = clone_stackframe(childstack, parentstack);
+ if (!childstack)
+ return -EFAULT;
#if 0
- printk("clone: child stack:\n");
- show_stackframe(childstack);
+ printk("clone: child stack:\n");
+ show_stackframe(childstack);
#endif
- childregs->u_regs[UREG_FP] = (unsigned long)childstack;
- }
+ childregs->u_regs[UREG_FP] = (unsigned long)childstack;
}
#ifdef CONFIG_SMP
@@ -503,41 +504,6 @@
return error;
}
-/*
- * This is the mechanism for creating a new kernel thread.
- *
- * NOTE! Only a kernel-only process(ie the swapper or direct descendants
- * who haven't done an "execve()") should use this: it will work within
- * a system call from a "real" process, but the process memory space will
- * not be freed until both the parent and the child have exited.
- */
-pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
- long retval;
-
- __asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */
- "mov %5, %%g3\n\t" /* and arg. */
- "mov %1, %%g1\n\t"
- "mov %2, %%o0\n\t" /* Clone flags. */
- "mov 0, %%o1\n\t" /* usp arg == 0 */
- "t 0x10\n\t" /* Linux/Sparc clone(). */
- "cmp %%o1, 0\n\t"
- "be 1f\n\t" /* The parent, just return. */
- " nop\n\t" /* Delay slot. */
- "jmpl %%g2, %%o7\n\t" /* Call the function. */
- " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
- "mov %3, %%g1\n\t"
- "t 0x10\n\t" /* Linux/Sparc exit(). */
- /* Notreached by child. */
- "1: mov %%o0, %0\n\t" :
- "=r" (retval) :
- "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
- "i" (__NR_exit), "r" (fn), "r" (arg) :
- "g1", "g2", "g3", "o0", "o1", "memory", "cc");
- return retval;
-}
-EXPORT_SYMBOL(kernel_thread);
-
unsigned long get_wchan(struct task_struct *task)
{
unsigned long pc, fp, bias = 0;