1// SPDX-License-Identifier: GPL-2.0
2
3/*
4 * This file handles the architecture independent parts of process handling..
5 */
6
7#include <linux/compat.h>
8#include <linux/errno.h>
9#include <linux/kernel.h>
10#include <linux/ptrace.h>
11#include <linux/sched.h>
12#include <linux/sched/task.h>
13#include <linux/sched/task_stack.h>
14#include <linux/signal.h>
15
16#include "kernel.h"
17
18asmlinkage long sparc_fork(struct pt_regs *regs)
19{
20	unsigned long orig_i1 = regs->u_regs[UREG_I1];
21	long ret;
22	struct kernel_clone_args args = {
23		.exit_signal	= SIGCHLD,
24		/* Reuse the parent's stack for the child. */
25		.stack		= regs->u_regs[UREG_FP],
26	};
27
28	ret = kernel_clone(&args);
29
30	/* If we get an error and potentially restart the system
31	 * call, we're screwed because copy_thread() clobbered
32	 * the parent's %o1.  So detect that case and restore it
33	 * here.
34	 */
35	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
36		regs->u_regs[UREG_I1] = orig_i1;
37
38	return ret;
39}
40
41asmlinkage long sparc_vfork(struct pt_regs *regs)
42{
43	unsigned long orig_i1 = regs->u_regs[UREG_I1];
44	long ret;
45
46	struct kernel_clone_args args = {
47		.flags		= CLONE_VFORK | CLONE_VM,
48		.exit_signal	= SIGCHLD,
49		/* Reuse the parent's stack for the child. */
50		.stack		= regs->u_regs[UREG_FP],
51	};
52
53	ret = kernel_clone(&args);
54
55	/* If we get an error and potentially restart the system
56	 * call, we're screwed because copy_thread() clobbered
57	 * the parent's %o1.  So detect that case and restore it
58	 * here.
59	 */
60	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
61		regs->u_regs[UREG_I1] = orig_i1;
62
63	return ret;
64}
65
66asmlinkage long sparc_clone(struct pt_regs *regs)
67{
68	unsigned long orig_i1 = regs->u_regs[UREG_I1];
69	unsigned int flags = lower_32_bits(regs->u_regs[UREG_I0]);
70	long ret;
71
72	struct kernel_clone_args args = {
73		.flags		= (flags & ~CSIGNAL),
74		.exit_signal	= (flags & CSIGNAL),
75		.tls		= regs->u_regs[UREG_I3],
76	};
77
78#ifdef CONFIG_COMPAT
79	if (test_thread_flag(TIF_32BIT)) {
80		args.pidfd	= compat_ptr(regs->u_regs[UREG_I2]);
81		args.child_tid	= compat_ptr(regs->u_regs[UREG_I4]);
82		args.parent_tid	= compat_ptr(regs->u_regs[UREG_I2]);
83	} else
84#endif
85	{
86		args.pidfd	= (int __user *)regs->u_regs[UREG_I2];
87		args.child_tid	= (int __user *)regs->u_regs[UREG_I4];
88		args.parent_tid	= (int __user *)regs->u_regs[UREG_I2];
89	}
90
91	/* Did userspace give setup a separate stack for the child or are we
92	 * reusing the parent's?
93	 */
94	if (regs->u_regs[UREG_I1])
95		args.stack = regs->u_regs[UREG_I1];
96	else
97		args.stack = regs->u_regs[UREG_FP];
98
99	ret = kernel_clone(&args);
100
101	/* If we get an error and potentially restart the system
102	 * call, we're screwed because copy_thread() clobbered
103	 * the parent's %o1.  So detect that case and restore it
104	 * here.
105	 */
106	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
107		regs->u_regs[UREG_I1] = orig_i1;
108
109	return ret;
110}
111