diff options
| -rw-r--r-- | arch/x86/kernel/i387.c | 88 |
1 files changed, 46 insertions, 42 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index d2e39e69aaf..8f8102d967b 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -5,45 +5,41 @@ * General FPU state handling cleanups * Gareth Hughes <gareth@valinux.com>, May 2000 */ - -#include <linux/sched.h> #include <linux/module.h> #include <linux/regset.h> +#include <linux/sched.h> + +#include <asm/sigcontext.h> #include <asm/processor.h> -#include <asm/i387.h> #include <asm/math_emu.h> -#include <asm/sigcontext.h> -#include <asm/user.h> -#include <asm/ptrace.h> #include <asm/uaccess.h> +#include <asm/ptrace.h> +#include <asm/i387.h> +#include <asm/user.h> #ifdef CONFIG_X86_64 - -#include <asm/sigcontext32.h> -#include <asm/user32.h> - +# include <asm/sigcontext32.h> +# include <asm/user32.h> #else - -#define save_i387_ia32 save_i387 -#define restore_i387_ia32 restore_i387 - -#define _fpstate_ia32 _fpstate -#define user_i387_ia32_struct user_i387_struct -#define user32_fxsr_struct user_fxsr_struct - +# define save_i387_ia32 save_i387 +# define restore_i387_ia32 restore_i387 +# define _fpstate_ia32 _fpstate +# define user_i387_ia32_struct user_i387_struct +# define user32_fxsr_struct user_fxsr_struct #endif #ifdef CONFIG_MATH_EMULATION -#define HAVE_HWFP (boot_cpu_data.hard_math) +# define HAVE_HWFP (boot_cpu_data.hard_math) #else -#define HAVE_HWFP 1 +# define HAVE_HWFP 1 #endif -static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu; +static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu; void mxcsr_feature_mask_init(void) { unsigned long mask = 0; + clts(); if (cpu_has_fxsr) { memset(¤t->thread.i387.fxsave, 0, @@ -69,10 +65,11 @@ void __cpuinit fpu_init(void) if (offsetof(struct task_struct, thread.i387.fxsave) & 15) __bad_fxsave_alignment(); + set_in_cr4(X86_CR4_OSFXSR); set_in_cr4(X86_CR4_OSXMMEXCPT); - write_cr0(oldcr0 & ~((1UL<<3)|(1UL<<2))); /* clear TS and EM */ + write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */ mxcsr_feature_mask_init(); /* clean state in init */ @@ -178,6 +175,7 @@ static inline unsigned short twd_i387_to_fxsr(unsigned short twd) tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */ + return tmp; } @@ -232,8 +230,8 @@ static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave) * FXSR floating point environment conversions. */ -static void convert_from_fxsr(struct user_i387_ia32_struct *env, - struct task_struct *tsk) +static void +convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk) { struct i387_fxsave_struct *fxsave = &tsk->thread.i387.fxsave; struct _fpreg *to = (struct _fpreg *) &env->st_space[0]; @@ -252,10 +250,11 @@ static void convert_from_fxsr(struct user_i387_ia32_struct *env, * should be actually ds/cs at fpu exception time, but * that information is not available in 64bit mode. */ - asm("mov %%ds,%0" : "=r" (env->fos)); - asm("mov %%cs,%0" : "=r" (env->fcs)); + asm("mov %%ds, %[fos]" : [fos] "=r" (env->fos)); + asm("mov %%cs, %[fcs]" : [fcs] "=r" (env->fcs)); } else { struct pt_regs *regs = task_pt_regs(tsk); + env->fos = 0xffff0000 | tsk->thread.ds; env->fcs = regs->cs; } @@ -309,9 +308,10 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset, init_fpu(target); - if (!cpu_has_fxsr) + if (!cpu_has_fxsr) { return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.i387.fsave, 0, -1); + } if (kbuf && pos == 0 && count == sizeof(env)) { convert_from_fxsr(kbuf, target); @@ -319,6 +319,7 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset, } convert_from_fxsr(&env, target); + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1); } @@ -335,9 +336,10 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, init_fpu(target); set_stopped_child_used_math(target); - if (!cpu_has_fxsr) + if (!cpu_has_fxsr) { return user_regset_copyin(&pos, &count, &kbuf, &ubuf, &target->thread.i387.fsave, 0, -1); + } if (pos > 0 || count < sizeof(env)) convert_from_fxsr(&env, target); @@ -392,28 +394,28 @@ int save_i387_ia32(struct _fpstate_ia32 __user *buf) { if (!used_math()) return 0; - - /* This will cause a "finit" to be triggered by the next + /* + * This will cause a "finit" to be triggered by the next * attempted FPU operation by the 'current' process. */ clear_used_math(); - if (HAVE_HWFP) { - if (cpu_has_fxsr) { - return save_i387_fxsave(buf); - } else { - return save_i387_fsave(buf); - } - } else { + if (!HAVE_HWFP) { return fpregs_soft_get(current, NULL, 0, sizeof(struct user_i387_ia32_struct), NULL, buf) ? -1 : 1; } + + if (cpu_has_fxsr) + return save_i387_fxsave(buf); + else + return save_i387_fsave(buf); } static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; + clear_fpu(tsk); return __copy_from_user(&tsk->thread.i387.fsave, buf, sizeof(struct i387_fsave_struct)); @@ -421,9 +423,10 @@ static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf) static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf) { - int err; struct task_struct *tsk = current; struct user_i387_ia32_struct env; + int err; + clear_fpu(tsk); err = __copy_from_user(&tsk->thread.i387.fxsave, &buf->_fxsr_env[0], sizeof(struct i387_fxsave_struct)); @@ -432,6 +435,7 @@ static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf) if (err || __copy_from_user(&env, buf, sizeof(env))) return 1; convert_to_fxsr(tsk, &env); + return 0; } @@ -440,17 +444,17 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf) int err; if (HAVE_HWFP) { - if (cpu_has_fxsr) { + if (cpu_has_fxsr) err = restore_i387_fxsave(buf); - } else { + else err = restore_i387_fsave(buf); - } } else { err = fpregs_soft_set(current, NULL, 0, sizeof(struct user_i387_ia32_struct), NULL, buf) != 0; } set_used_math(); + return err; } @@ -463,8 +467,8 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf) */ int dump_fpu(struct pt_regs *regs, struct user_i387_struct *fpu) { - int fpvalid; struct task_struct *tsk = current; + int fpvalid; fpvalid = !!used_math(); if (fpvalid) |