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authorThomas Gleixner <tglx@linutronix.de>2007-10-11 05:17:24 -0400
committerThomas Gleixner <tglx@linutronix.de>2007-10-11 05:17:24 -0400
commit250c22777fe1ccd7ac588579a6c16db4c0161cc5 (patch)
tree55c317efb7d792ec6fdae1d1937c67a502c48dec /arch/x86/kernel/i387_64.c
parent2db55d344e529492545cb3b755c7e9ba8e4fa94e (diff)
x86_64: move kernel
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/i387_64.c')
-rw-r--r--arch/x86/kernel/i387_64.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/x86/kernel/i387_64.c b/arch/x86/kernel/i387_64.c
new file mode 100644
index 000000000000..1d58c13bc6bc
--- /dev/null
+++ b/arch/x86/kernel/i387_64.c
@@ -0,0 +1,151 @@
1/*
2 * linux/arch/x86_64/kernel/i387.c
3 *
4 * Copyright (C) 1994 Linus Torvalds
5 * Copyright (C) 2002 Andi Kleen, SuSE Labs
6 *
7 * Pentium III FXSR, SSE support
8 * General FPU state handling cleanups
9 * Gareth Hughes <gareth@valinux.com>, May 2000
10 *
11 * x86-64 rework 2002 Andi Kleen.
12 * Does direct fxsave in and out of user space now for signal handlers.
13 * All the FSAVE<->FXSAVE conversion code has been moved to the 32bit emulation,
14 * the 64bit user space sees a FXSAVE frame directly.
15 */
16
17#include <linux/sched.h>
18#include <linux/init.h>
19#include <asm/processor.h>
20#include <asm/i387.h>
21#include <asm/sigcontext.h>
22#include <asm/user.h>
23#include <asm/ptrace.h>
24#include <asm/uaccess.h>
25
26unsigned int mxcsr_feature_mask __read_mostly = 0xffffffff;
27
28void mxcsr_feature_mask_init(void)
29{
30 unsigned int mask;
31 clts();
32 memset(&current->thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
33 asm volatile("fxsave %0" : : "m" (current->thread.i387.fxsave));
34 mask = current->thread.i387.fxsave.mxcsr_mask;
35 if (mask == 0) mask = 0x0000ffbf;
36 mxcsr_feature_mask &= mask;
37 stts();
38}
39
40/*
41 * Called at bootup to set up the initial FPU state that is later cloned
42 * into all processes.
43 */
44void __cpuinit fpu_init(void)
45{
46 unsigned long oldcr0 = read_cr0();
47 extern void __bad_fxsave_alignment(void);
48
49 if (offsetof(struct task_struct, thread.i387.fxsave) & 15)
50 __bad_fxsave_alignment();
51 set_in_cr4(X86_CR4_OSFXSR);
52 set_in_cr4(X86_CR4_OSXMMEXCPT);
53
54 write_cr0(oldcr0 & ~((1UL<<3)|(1UL<<2))); /* clear TS and EM */
55
56 mxcsr_feature_mask_init();
57 /* clean state in init */
58 current_thread_info()->status = 0;
59 clear_used_math();
60}
61
62void init_fpu(struct task_struct *child)
63{
64 if (tsk_used_math(child)) {
65 if (child == current)
66 unlazy_fpu(child);
67 return;
68 }
69 memset(&child->thread.i387.fxsave, 0, sizeof(struct i387_fxsave_struct));
70 child->thread.i387.fxsave.cwd = 0x37f;
71 child->thread.i387.fxsave.mxcsr = 0x1f80;
72 /* only the device not available exception or ptrace can call init_fpu */
73 set_stopped_child_used_math(child);
74}
75
76/*
77 * Signal frame handlers.
78 */
79
80int save_i387(struct _fpstate __user *buf)
81{
82 struct task_struct *tsk = current;
83 int err = 0;
84
85 BUILD_BUG_ON(sizeof(struct user_i387_struct) !=
86 sizeof(tsk->thread.i387.fxsave));
87
88 if ((unsigned long)buf % 16)
89 printk("save_i387: bad fpstate %p\n",buf);
90
91 if (!used_math())
92 return 0;
93 clear_used_math(); /* trigger finit */
94 if (task_thread_info(tsk)->status & TS_USEDFPU) {
95 err = save_i387_checking((struct i387_fxsave_struct __user *)buf);
96 if (err) return err;
97 stts();
98 } else {
99 if (__copy_to_user(buf, &tsk->thread.i387.fxsave,
100 sizeof(struct i387_fxsave_struct)))
101 return -1;
102 }
103 return 1;
104}
105
106/*
107 * ptrace request handlers.
108 */
109
110int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *tsk)
111{
112 init_fpu(tsk);
113 return __copy_to_user(buf, &tsk->thread.i387.fxsave,
114 sizeof(struct user_i387_struct)) ? -EFAULT : 0;
115}
116
117int set_fpregs(struct task_struct *tsk, struct user_i387_struct __user *buf)
118{
119 if (__copy_from_user(&tsk->thread.i387.fxsave, buf,
120 sizeof(struct user_i387_struct)))
121 return -EFAULT;
122 return 0;
123}
124
125/*
126 * FPU state for core dumps.
127 */
128
129int dump_fpu( struct pt_regs *regs, struct user_i387_struct *fpu )
130{
131 struct task_struct *tsk = current;
132
133 if (!used_math())
134 return 0;
135
136 unlazy_fpu(tsk);
137 memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(struct user_i387_struct));
138 return 1;
139}
140
141int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu)
142{
143 int fpvalid = !!tsk_used_math(tsk);
144
145 if (fpvalid) {
146 if (tsk == current)
147 unlazy_fpu(tsk);
148 memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(struct user_i387_struct));
149}
150 return fpvalid;
151}