1#include <linux/mm.h>
2#include <linux/kernel.h>
3#include <linux/slab.h>
4#include <linux/sched.h>
5#include <linux/export.h>
6#include <linux/stackprotector.h>
7#include <asm/fpu.h>
8
9struct kmem_cache *task_xstate_cachep = NULL;
10unsigned int xstate_size;
11
12#ifdef CONFIG_CC_STACKPROTECTOR
13unsigned long __stack_chk_guard __read_mostly;
14EXPORT_SYMBOL(__stack_chk_guard);
15#endif
16
17/*
18 * this gets called so that we can store lazy state into memory and copy the
19 * current task into the new thread.
20 */
21int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
22{
23#ifdef CONFIG_SUPERH32
24	unlazy_fpu(src, task_pt_regs(src));
25#endif
26	*dst = *src;
27
28	if (src->thread.xstate) {
29		dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
30						      GFP_KERNEL);
31		if (!dst->thread.xstate)
32			return -ENOMEM;
33		memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
34	}
35
36	return 0;
37}
38
39void free_thread_xstate(struct task_struct *tsk)
40{
41	if (tsk->thread.xstate) {
42		kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
43		tsk->thread.xstate = NULL;
44	}
45}
46
47void arch_release_task_struct(struct task_struct *tsk)
48{
49	free_thread_xstate(tsk);
50}
51
52void arch_task_cache_init(void)
53{
54	if (!xstate_size)
55		return;
56
57	task_xstate_cachep = kmem_cache_create("task_xstate", xstate_size,
58					       __alignof__(union thread_xstate),
59					       SLAB_PANIC | SLAB_NOTRACK, NULL);
60}
61
62#ifdef CONFIG_SH_FPU_EMU
63# define HAVE_SOFTFP	1
64#else
65# define HAVE_SOFTFP	0
66#endif
67
68void init_thread_xstate(void)
69{
70	if (boot_cpu_data.flags & CPU_HAS_FPU)
71		xstate_size = sizeof(struct sh_fpu_hard_struct);
72	else if (HAVE_SOFTFP)
73		xstate_size = sizeof(struct sh_fpu_soft_struct);
74	else
75		xstate_size = 0;
76}
77