1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/mm.h>
 3#include <linux/kernel.h>
 4#include <linux/slab.h>
 5#include <linux/sched/signal.h>
 6#include <linux/sched/task_stack.h>
 7#include <linux/export.h>
 8#include <linux/stackprotector.h>
 9#include <asm/fpu.h>
10#include <asm/ptrace.h>
11
12struct kmem_cache *task_xstate_cachep = NULL;
13unsigned int xstate_size;
14
15#ifdef CONFIG_STACKPROTECTOR
16unsigned long __stack_chk_guard __read_mostly;
17EXPORT_SYMBOL(__stack_chk_guard);
18#endif
19
20/*
21 * this gets called so that we can store lazy state into memory and copy the
22 * current task into the new thread.
23 */
24int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
25{
26	unlazy_fpu(src, task_pt_regs(src));
27	*dst = *src;
28
29	if (src->thread.xstate) {
30		dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
31						      GFP_KERNEL);
32		if (!dst->thread.xstate)
33			return -ENOMEM;
34		memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
35	}
36
37	return 0;
38}
39
40void free_thread_xstate(struct task_struct *tsk)
41{
42	if (tsk->thread.xstate) {
43		kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
44		tsk->thread.xstate = NULL;
45	}
46}
47
48void arch_release_task_struct(struct task_struct *tsk)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
49{
50	free_thread_xstate(tsk);
 
51}
 
52
53void arch_task_cache_init(void)
54{
55	if (!xstate_size)
56		return;
57
58	task_xstate_cachep = kmem_cache_create("task_xstate", xstate_size,
59					       __alignof__(union thread_xstate),
60					       SLAB_PANIC, NULL);
61}
62
63#ifdef CONFIG_SH_FPU_EMU
64# define HAVE_SOFTFP	1
65#else
66# define HAVE_SOFTFP	0
67#endif
68
69void init_thread_xstate(void)
70{
71	if (boot_cpu_data.flags & CPU_HAS_FPU)
72		xstate_size = sizeof(struct sh_fpu_hard_struct);
73	else if (HAVE_SOFTFP)
74		xstate_size = sizeof(struct sh_fpu_soft_struct);
75	else
76		xstate_size = 0;
77}

 
  1#include <linux/mm.h>
  2#include <linux/kernel.h>
  3#include <linux/slab.h>
  4#include <linux/sched.h>
 
 
 
 
 
  5
  6struct kmem_cache *task_xstate_cachep = NULL;
  7unsigned int xstate_size;
  8
 
 
 
 
 
 
 
 
 
  9int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
 10{
 
 11	*dst = *src;
 12
 13	if (src->thread.xstate) {
 14		dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
 15						      GFP_KERNEL);
 16		if (!dst->thread.xstate)
 17			return -ENOMEM;
 18		memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
 19	}
 20
 21	return 0;
 22}
 23
 24void free_thread_xstate(struct task_struct *tsk)
 25{
 26	if (tsk->thread.xstate) {
 27		kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
 28		tsk->thread.xstate = NULL;
 29	}
 30}
 31
 32#if THREAD_SHIFT < PAGE_SHIFT
 33static struct kmem_cache *thread_info_cache;
 34
 35struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node)
 36{
 37	struct thread_info *ti;
 38#ifdef CONFIG_DEBUG_STACK_USAGE
 39	gfp_t mask = GFP_KERNEL | __GFP_ZERO;
 40#else
 41	gfp_t mask = GFP_KERNEL;
 42#endif
 43
 44	ti = kmem_cache_alloc_node(thread_info_cache, mask, node);
 45	return ti;
 46}
 47
 48void free_thread_info(struct thread_info *ti)
 49{
 50	free_thread_xstate(ti->task);
 51	kmem_cache_free(thread_info_cache, ti);
 52}
 53
 54void thread_info_cache_init(void)
 55{
 56	thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
 57					      THREAD_SIZE, SLAB_PANIC, NULL);
 58}
 59#else
 60struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node)
 61{
 62#ifdef CONFIG_DEBUG_STACK_USAGE
 63	gfp_t mask = GFP_KERNEL | __GFP_ZERO;
 64#else
 65	gfp_t mask = GFP_KERNEL;
 66#endif
 67	struct page *page = alloc_pages_node(node, mask, THREAD_SIZE_ORDER);
 68
 69	return page ? page_address(page) : NULL;
 70}
 71
 72void free_thread_info(struct thread_info *ti)
 73{
 74	free_thread_xstate(ti->task);
 75	free_pages((unsigned long)ti, THREAD_SIZE_ORDER);
 76}
 77#endif /* THREAD_SHIFT < PAGE_SHIFT */
 78
 79void arch_task_cache_init(void)
 80{
 81	if (!xstate_size)
 82		return;
 83
 84	task_xstate_cachep = kmem_cache_create("task_xstate", xstate_size,
 85					       __alignof__(union thread_xstate),
 86					       SLAB_PANIC | SLAB_NOTRACK, NULL);
 87}
 88
 89#ifdef CONFIG_SH_FPU_EMU
 90# define HAVE_SOFTFP	1
 91#else
 92# define HAVE_SOFTFP	0
 93#endif
 94
 95void __cpuinit init_thread_xstate(void)
 96{
 97	if (boot_cpu_data.flags & CPU_HAS_FPU)
 98		xstate_size = sizeof(struct sh_fpu_hard_struct);
 99	else if (HAVE_SOFTFP)
100		xstate_size = sizeof(struct sh_fpu_soft_struct);
101	else
102		xstate_size = 0;
103}