1#include <linux/sched.h>
 2#include <linux/slab.h>
 3#include <asm/processor.h>
 4#include <asm/fpu.h>
 5#include <asm/traps.h>
 6
 7int init_fpu(struct task_struct *tsk)
 8{
 9	if (tsk_used_math(tsk)) {
10		if ((boot_cpu_data.flags & CPU_HAS_FPU) && tsk == current)
11			unlazy_fpu(tsk, task_pt_regs(tsk));
12		return 0;
13	}
14
15	/*
16	 * Memory allocation at the first usage of the FPU and other state.
17	 */
18	if (!tsk->thread.xstate) {
19		tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
20						      GFP_KERNEL);
21		if (!tsk->thread.xstate)
22			return -ENOMEM;
23	}
24
25	if (boot_cpu_data.flags & CPU_HAS_FPU) {
26		struct sh_fpu_hard_struct *fp = &tsk->thread.xstate->hardfpu;
27		memset(fp, 0, xstate_size);
28		fp->fpscr = FPSCR_INIT;
29	} else {
30		struct sh_fpu_soft_struct *fp = &tsk->thread.xstate->softfpu;
31		memset(fp, 0, xstate_size);
32		fp->fpscr = FPSCR_INIT;
33	}
34
35	set_stopped_child_used_math(tsk);
36	return 0;
37}
38
39#ifdef CONFIG_SH_FPU
40void __fpu_state_restore(void)
41{
42	struct task_struct *tsk = current;
43
44	restore_fpu(tsk);
45
46	task_thread_info(tsk)->status |= TS_USEDFPU;
47	tsk->fpu_counter++;
48}
49
50void fpu_state_restore(struct pt_regs *regs)
51{
52	struct task_struct *tsk = current;
53
54	if (unlikely(!user_mode(regs))) {
55		printk(KERN_ERR "BUG: FPU is used in kernel mode.\n");
56		BUG();
57		return;
58	}
59
60	if (!tsk_used_math(tsk)) {
61		local_irq_enable();
62		/*
63		 * does a slab alloc which can sleep
64		 */
65		if (init_fpu(tsk)) {
66			/*
67			 * ran out of memory!
68			 */
69			do_group_exit(SIGKILL);
70			return;
71		}
72		local_irq_disable();
73	}
74
75	grab_fpu(regs);
76
77	__fpu_state_restore();
78}
79
80BUILD_TRAP_HANDLER(fpu_state_restore)
81{
82	TRAP_HANDLER_DECL;
83
84	fpu_state_restore(regs);
85}
86#endif /* CONFIG_SH_FPU */

 1#include <linux/sched.h>
 2#include <linux/slab.h>
 3#include <asm/processor.h>
 4#include <asm/fpu.h>
 
 5
 6int init_fpu(struct task_struct *tsk)
 7{
 8	if (tsk_used_math(tsk)) {
 9		if ((boot_cpu_data.flags & CPU_HAS_FPU) && tsk == current)
10			unlazy_fpu(tsk, task_pt_regs(tsk));
11		return 0;
12	}
13
14	/*
15	 * Memory allocation at the first usage of the FPU and other state.
16	 */
17	if (!tsk->thread.xstate) {
18		tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
19						      GFP_KERNEL);
20		if (!tsk->thread.xstate)
21			return -ENOMEM;
22	}
23
24	if (boot_cpu_data.flags & CPU_HAS_FPU) {
25		struct sh_fpu_hard_struct *fp = &tsk->thread.xstate->hardfpu;
26		memset(fp, 0, xstate_size);
27		fp->fpscr = FPSCR_INIT;
28	} else {
29		struct sh_fpu_soft_struct *fp = &tsk->thread.xstate->softfpu;
30		memset(fp, 0, xstate_size);
31		fp->fpscr = FPSCR_INIT;
32	}
33
34	set_stopped_child_used_math(tsk);
35	return 0;
36}
37
38#ifdef CONFIG_SH_FPU
39void __fpu_state_restore(void)
40{
41	struct task_struct *tsk = current;
42
43	restore_fpu(tsk);
44
45	task_thread_info(tsk)->status |= TS_USEDFPU;
46	tsk->fpu_counter++;
47}
48
49void fpu_state_restore(struct pt_regs *regs)
50{
51	struct task_struct *tsk = current;
52
53	if (unlikely(!user_mode(regs))) {
54		printk(KERN_ERR "BUG: FPU is used in kernel mode.\n");
55		BUG();
56		return;
57	}
58
59	if (!tsk_used_math(tsk)) {
60		local_irq_enable();
61		/*
62		 * does a slab alloc which can sleep
63		 */
64		if (init_fpu(tsk)) {
65			/*
66			 * ran out of memory!
67			 */
68			do_group_exit(SIGKILL);
69			return;
70		}
71		local_irq_disable();
72	}
73
74	grab_fpu(regs);
75
76	__fpu_state_restore();
77}
78
79BUILD_TRAP_HANDLER(fpu_state_restore)
80{
81	TRAP_HANDLER_DECL;
82
83	fpu_state_restore(regs);
84}
85#endif /* CONFIG_SH_FPU */