X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fi387.c;h=14ca1dc7a7039f37cb5cb3f5cfa16186af12224f;hb=c9ad488289144ae5ef53b012e15895ef1f5e4bb6;hp=bebe0346346103309061c4c3890f5acc81f3045a;hpb=b7b71725fb9584454bfe5f231223bd63421798fb;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index bebe034..14ca1dc 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -5,34 +5,53 @@ * General FPU state handling cleanups * Gareth Hughes , May 2000 */ - -#include #include +#include +#include +#include + +#include #include -#include #include -#include -#include -#include #include +#include +#include +#include + +#ifdef CONFIG_X86_64 +# include +# include +#else +# define save_i387_xstate_ia32 save_i387_xstate +# define restore_i387_xstate_ia32 restore_i387_xstate +# define _fpstate_ia32 _fpstate +# define _xstate_ia32 _xstate +# define sig_xstate_ia32_size sig_xstate_size +# define fx_sw_reserved_ia32 fx_sw_reserved +# 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 long mxcsr_feature_mask __read_mostly = 0xffffffff; +static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu; +unsigned int xstate_size; +unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32); +static struct i387_fxsave_struct fx_scratch __cpuinitdata; -void mxcsr_feature_mask_init(void) +void __cpuinit mxcsr_feature_mask_init(void) { unsigned long mask = 0; + clts(); if (cpu_has_fxsr) { - memset(¤t->thread.i387.fxsave, 0, - sizeof(struct i387_fxsave_struct)); - asm volatile("fxsave %0" : : "m" (current->thread.i387.fxsave)); - mask = current->thread.i387.fxsave.mxcsr_mask; + memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct)); + asm volatile("fxsave %0" : : "m" (fx_scratch)); + mask = fx_scratch.mxcsr_mask; if (mask == 0) mask = 0x0000ffbf; } @@ -40,49 +59,235 @@ void mxcsr_feature_mask_init(void) stts(); } +void __cpuinit init_thread_xstate(void) +{ + if (!HAVE_HWFP) { + xstate_size = sizeof(struct i387_soft_struct); + return; + } + + if (cpu_has_xsave) { + xsave_cntxt_init(); + return; + } + + if (cpu_has_fxsr) + xstate_size = sizeof(struct i387_fxsave_struct); +#ifdef CONFIG_X86_32 + else + xstate_size = sizeof(struct i387_fsave_struct); +#endif +} + +#ifdef CONFIG_X86_64 +/* + * Called at bootup to set up the initial FPU state that is later cloned + * into all processes. + */ +void __cpuinit fpu_init(void) +{ + unsigned long oldcr0 = read_cr0(); + + set_in_cr4(X86_CR4_OSFXSR); + set_in_cr4(X86_CR4_OSXMMEXCPT); + + write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */ + + /* + * Boot processor to setup the FP and extended state context info. + */ + if (!smp_processor_id()) + init_thread_xstate(); + xsave_init(); + + mxcsr_feature_mask_init(); + /* clean state in init */ + current_thread_info()->status = 0; + clear_used_math(); +} +#endif /* CONFIG_X86_64 */ + /* * The _current_ task is using the FPU for the first time * so initialize it and set the mxcsr to its default * value at reset if we support XMM instructions and then * remeber the current task has used the FPU. */ -void init_fpu(struct task_struct *tsk) +int init_fpu(struct task_struct *tsk) { + if (tsk_used_math(tsk)) { + if (HAVE_HWFP && tsk == current) + unlazy_fpu(tsk); + return 0; + } + + /* + * Memory allocation at the first usage of the FPU and other state. + */ + if (!tsk->thread.xstate) { + tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep, + GFP_KERNEL); + if (!tsk->thread.xstate) + return -ENOMEM; + } + +#ifdef CONFIG_X86_32 + if (!HAVE_HWFP) { + memset(tsk->thread.xstate, 0, xstate_size); + finit_task(tsk); + set_stopped_child_used_math(tsk); + return 0; + } +#endif + if (cpu_has_fxsr) { - memset(&tsk->thread.i387.fxsave, 0, - sizeof(struct i387_fxsave_struct)); - tsk->thread.i387.fxsave.cwd = 0x37f; + struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave; + + memset(fx, 0, xstate_size); + fx->cwd = 0x37f; if (cpu_has_xmm) - tsk->thread.i387.fxsave.mxcsr = 0x1f80; + fx->mxcsr = MXCSR_DEFAULT; } else { - memset(&tsk->thread.i387.fsave, 0, - sizeof(struct i387_fsave_struct)); - tsk->thread.i387.fsave.cwd = 0xffff037fu; - tsk->thread.i387.fsave.swd = 0xffff0000u; - tsk->thread.i387.fsave.twd = 0xffffffffu; - tsk->thread.i387.fsave.fos = 0xffff0000u; + struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave; + memset(fp, 0, xstate_size); + fp->cwd = 0xffff037fu; + fp->swd = 0xffff0000u; + fp->twd = 0xffffffffu; + fp->fos = 0xffff0000u; } - /* only the device not available exception - * or ptrace can call init_fpu */ + /* + * Only the device not available exception or ptrace can call init_fpu. + */ set_stopped_child_used_math(tsk); + return 0; } /* - * FPU lazy state save handling. + * The xstateregs_active() routine is the same as the fpregs_active() routine, + * as the "regset->n" for the xstate regset will be updated based on the feature + * capabilites supported by the xsave. */ +int fpregs_active(struct task_struct *target, const struct user_regset *regset) +{ + return tsk_used_math(target) ? regset->n : 0; +} -void kernel_fpu_begin(void) +int xfpregs_active(struct task_struct *target, const struct user_regset *regset) { - struct thread_info *thread = current_thread_info(); + return (cpu_has_fxsr && tsk_used_math(target)) ? regset->n : 0; +} - preempt_disable(); - if (thread->status & TS_USEDFPU) { - __save_init_fpu(thread->task); - return; - } - clts(); +int xfpregs_get(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + int ret; + + if (!cpu_has_fxsr) + return -ENODEV; + + ret = init_fpu(target); + if (ret) + return ret; + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.xstate->fxsave, 0, -1); } -EXPORT_SYMBOL_GPL(kernel_fpu_begin); + +int xfpregs_set(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + + if (!cpu_has_fxsr) + return -ENODEV; + + ret = init_fpu(target); + if (ret) + return ret; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.xstate->fxsave, 0, -1); + + /* + * mxcsr reserved bits must be masked to zero for security reasons. + */ + target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; + + /* + * update the header bits in the xsave header, indicating the + * presence of FP and SSE state. + */ + if (cpu_has_xsave) + target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; + + return ret; +} + +int xstateregs_get(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + int ret; + + if (!cpu_has_xsave) + return -ENODEV; + + ret = init_fpu(target); + if (ret) + return ret; + + /* + * Copy the 48bytes defined by the software first into the xstate + * memory layout in the thread struct, so that we can copy the entire + * xstateregs to the user using one user_regset_copyout(). + */ + memcpy(&target->thread.xstate->fxsave.sw_reserved, + xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes)); + + /* + * Copy the xstate memory layout. + */ + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.xstate->xsave, 0, -1); + return ret; +} + +int xstateregs_set(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + struct xsave_hdr_struct *xsave_hdr; + + if (!cpu_has_xsave) + return -ENODEV; + + ret = init_fpu(target); + if (ret) + return ret; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.xstate->xsave, 0, -1); + + /* + * mxcsr reserved bits must be masked to zero for security reasons. + */ + target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; + + xsave_hdr = &target->thread.xstate->xsave.xsave_hdr; + + xsave_hdr->xstate_bv &= pcntxt_mask; + /* + * These bits must be zero. + */ + xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0; + + return ret; +} + +#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION /* * FPU tag word conversions. @@ -94,7 +299,7 @@ static inline unsigned short twd_i387_to_fxsr(unsigned short twd) /* Transform each pair of bits into 01 (valid) or 00 (empty) */ tmp = ~twd; - tmp = (tmp | (tmp >> 1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ + tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ /* and move the valid bits to the lower byte. */ tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ @@ -103,449 +308,423 @@ static inline unsigned short twd_i387_to_fxsr(unsigned short twd) return tmp; } -static inline unsigned long twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave) -{ - struct _fpxreg *st = NULL; - unsigned long tos = (fxsave->swd >> 11) & 7; - unsigned long twd = (unsigned long) fxsave->twd; - unsigned long tag; - unsigned long ret = 0xffff0000u; - int i; - #define FPREG_ADDR(f, n) ((void *)&(f)->st_space + (n) * 16); +#define FP_EXP_TAG_VALID 0 +#define FP_EXP_TAG_ZERO 1 +#define FP_EXP_TAG_SPECIAL 2 +#define FP_EXP_TAG_EMPTY 3 + +static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave) +{ + struct _fpxreg *st; + u32 tos = (fxsave->swd >> 11) & 7; + u32 twd = (unsigned long) fxsave->twd; + u32 tag; + u32 ret = 0xffff0000u; + int i; - for (i = 0; i < 8; i++) { + for (i = 0; i < 8; i++, twd >>= 1) { if (twd & 0x1) { st = FPREG_ADDR(fxsave, (i - tos) & 7); switch (st->exponent & 0x7fff) { case 0x7fff: - tag = 2; /* Special */ + tag = FP_EXP_TAG_SPECIAL; break; case 0x0000: if (!st->significand[0] && !st->significand[1] && !st->significand[2] && - !st->significand[3]) { - tag = 1; /* Zero */ - } else { - tag = 2; /* Special */ - } + !st->significand[3]) + tag = FP_EXP_TAG_ZERO; + else + tag = FP_EXP_TAG_SPECIAL; break; default: - if (st->significand[3] & 0x8000) { - tag = 0; /* Valid */ - } else { - tag = 2; /* Special */ - } + if (st->significand[3] & 0x8000) + tag = FP_EXP_TAG_VALID; + else + tag = FP_EXP_TAG_SPECIAL; break; } } else { - tag = 3; /* Empty */ + tag = FP_EXP_TAG_EMPTY; } - ret |= (tag << (2 * i)); - twd = twd >> 1; + ret |= tag << (2 * i); } return ret; } /* - * FPU state interaction. + * FXSR floating point environment conversions. */ -unsigned short get_fpu_cwd(struct task_struct *tsk) +static void +convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk) { - if (cpu_has_fxsr) { - return tsk->thread.i387.fxsave.cwd; - } else { - return (unsigned short)tsk->thread.i387.fsave.cwd; - } -} + struct i387_fxsave_struct *fxsave = &tsk->thread.xstate->fxsave; + struct _fpreg *to = (struct _fpreg *) &env->st_space[0]; + struct _fpxreg *from = (struct _fpxreg *) &fxsave->st_space[0]; + int i; -unsigned short get_fpu_swd(struct task_struct *tsk) -{ - if (cpu_has_fxsr) { - return tsk->thread.i387.fxsave.swd; + env->cwd = fxsave->cwd | 0xffff0000u; + env->swd = fxsave->swd | 0xffff0000u; + env->twd = twd_fxsr_to_i387(fxsave); + +#ifdef CONFIG_X86_64 + env->fip = fxsave->rip; + env->foo = fxsave->rdp; + if (tsk == current) { + /* + * should be actually ds/cs at fpu exception time, but + * that information is not available in 64bit mode. + */ + asm("mov %%ds, %[fos]" : [fos] "=r" (env->fos)); + asm("mov %%cs, %[fcs]" : [fcs] "=r" (env->fcs)); } else { - return (unsigned short)tsk->thread.i387.fsave.swd; - } -} + struct pt_regs *regs = task_pt_regs(tsk); -#if 0 -unsigned short get_fpu_twd(struct task_struct *tsk) -{ - if (cpu_has_fxsr) { - return tsk->thread.i387.fxsave.twd; - } else { - return (unsigned short)tsk->thread.i387.fsave.twd; + env->fos = 0xffff0000 | tsk->thread.ds; + env->fcs = regs->cs; } -} -#endif /* 0 */ +#else + env->fip = fxsave->fip; + env->fcs = (u16) fxsave->fcs | ((u32) fxsave->fop << 16); + env->foo = fxsave->foo; + env->fos = fxsave->fos; +#endif -unsigned short get_fpu_mxcsr(struct task_struct *tsk) -{ - if (cpu_has_xmm) { - return tsk->thread.i387.fxsave.mxcsr; - } else { - return 0x1f80; - } + for (i = 0; i < 8; ++i) + memcpy(&to[i], &from[i], sizeof(to[0])); } -#if 0 +static void convert_to_fxsr(struct task_struct *tsk, + const struct user_i387_ia32_struct *env) -void set_fpu_cwd(struct task_struct *tsk, unsigned short cwd) { - if (cpu_has_fxsr) { - tsk->thread.i387.fxsave.cwd = cwd; - } else { - tsk->thread.i387.fsave.cwd = ((long)cwd | 0xffff0000u); - } + struct i387_fxsave_struct *fxsave = &tsk->thread.xstate->fxsave; + struct _fpreg *from = (struct _fpreg *) &env->st_space[0]; + struct _fpxreg *to = (struct _fpxreg *) &fxsave->st_space[0]; + int i; + + fxsave->cwd = env->cwd; + fxsave->swd = env->swd; + fxsave->twd = twd_i387_to_fxsr(env->twd); + fxsave->fop = (u16) ((u32) env->fcs >> 16); +#ifdef CONFIG_X86_64 + fxsave->rip = env->fip; + fxsave->rdp = env->foo; + /* cs and ds ignored */ +#else + fxsave->fip = env->fip; + fxsave->fcs = (env->fcs & 0xffff); + fxsave->foo = env->foo; + fxsave->fos = env->fos; +#endif + + for (i = 0; i < 8; ++i) + memcpy(&to[i], &from[i], sizeof(from[0])); } -void set_fpu_swd(struct task_struct *tsk, unsigned short swd) +int fpregs_get(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) { - if (cpu_has_fxsr) { - tsk->thread.i387.fxsave.swd = swd; - } else { - tsk->thread.i387.fsave.swd = ((long)swd | 0xffff0000u); + struct user_i387_ia32_struct env; + int ret; + + ret = init_fpu(target); + if (ret) + return ret; + + if (!HAVE_HWFP) + return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf); + + if (!cpu_has_fxsr) { + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.xstate->fsave, 0, + -1); } -} -void set_fpu_twd(struct task_struct *tsk, unsigned short twd) -{ - if (cpu_has_fxsr) { - tsk->thread.i387.fxsave.twd = twd_i387_to_fxsr(twd); - } else { - tsk->thread.i387.fsave.twd = ((long)twd | 0xffff0000u); + if (kbuf && pos == 0 && count == sizeof(env)) { + convert_from_fxsr(kbuf, target); + return 0; } -} -#endif /* 0 */ + convert_from_fxsr(&env, target); -/* - * FXSR floating point environment conversions. - */ + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1); +} -static int convert_fxsr_to_user(struct _fpstate __user *buf, - struct i387_fxsave_struct *fxsave) +int fpregs_set(struct task_struct *target, const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) { - unsigned long env[7]; - struct _fpreg __user *to; - struct _fpxreg *from; - int i; + struct user_i387_ia32_struct env; + int ret; - env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul; - env[1] = (unsigned long)fxsave->swd | 0xffff0000ul; - env[2] = twd_fxsr_to_i387(fxsave); - env[3] = fxsave->fip; - env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16); - env[5] = fxsave->foo; - env[6] = fxsave->fos; - - if (__copy_to_user(buf, env, 7 * sizeof(unsigned long))) - return 1; + ret = init_fpu(target); + if (ret) + return ret; - to = &buf->_st[0]; - from = (struct _fpxreg *) &fxsave->st_space[0]; - for (i = 0; i < 8; i++, to++, from++) { - unsigned long __user *t = (unsigned long __user *)to; - unsigned long *f = (unsigned long *)from; + if (!HAVE_HWFP) + return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf); - if (__put_user(*f, t) || - __put_user(*(f + 1), t + 1) || - __put_user(from->exponent, &to->exponent)) - return 1; + if (!cpu_has_fxsr) { + return user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.xstate->fsave, 0, -1); } - return 0; -} -static int convert_fxsr_from_user(struct i387_fxsave_struct *fxsave, - struct _fpstate __user *buf) -{ - unsigned long env[7]; - struct _fpxreg *to; - struct _fpreg __user *from; - int i; + if (pos > 0 || count < sizeof(env)) + convert_from_fxsr(&env, target); - if (__copy_from_user(env, buf, 7 * sizeof(long))) - return 1; + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &env, 0, -1); + if (!ret) + convert_to_fxsr(target, &env); - fxsave->cwd = (unsigned short)(env[0] & 0xffff); - fxsave->swd = (unsigned short)(env[1] & 0xffff); - fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff)); - fxsave->fip = env[3]; - fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16); - fxsave->fcs = (env[4] & 0xffff); - fxsave->foo = env[5]; - fxsave->fos = env[6]; - - to = (struct _fpxreg *) &fxsave->st_space[0]; - from = &buf->_st[0]; - for (i = 0; i < 8; i++, to++, from++) { - unsigned long *t = (unsigned long *)to; - unsigned long __user *f = (unsigned long __user *)from; - - if (__get_user(*t, f) || - __get_user(*(t + 1), f + 1) || - __get_user(to->exponent, &from->exponent)) - return 1; - } - return 0; + /* + * update the header bit in the xsave header, indicating the + * presence of FP. + */ + if (cpu_has_xsave) + target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FP; + return ret; } /* * Signal frame handlers. */ -static inline int save_i387_fsave(struct _fpstate __user *buf) +static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; + struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave; - unlazy_fpu(tsk); - tsk->thread.i387.fsave.status = tsk->thread.i387.fsave.swd; - if (__copy_to_user(buf, &tsk->thread.i387.fsave, - sizeof(struct i387_fsave_struct))) + fp->status = fp->swd; + if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct))) return -1; return 1; } -static int save_i387_fxsave(struct _fpstate __user *buf) +static int save_i387_fxsave(struct _fpstate_ia32 __user *buf) { struct task_struct *tsk = current; + struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave; + struct user_i387_ia32_struct env; int err = 0; - unlazy_fpu(tsk); - - if (convert_fxsr_to_user(buf, &tsk->thread.i387.fxsave)) + convert_from_fxsr(&env, tsk); + if (__copy_to_user(buf, &env, sizeof(env))) return -1; - err |= __put_user(tsk->thread.i387.fxsave.swd, &buf->status); + err |= __put_user(fx->swd, &buf->status); err |= __put_user(X86_FXSR_MAGIC, &buf->magic); if (err) return -1; - if (__copy_to_user(&buf->_fxsr_env[0], &tsk->thread.i387.fxsave, - sizeof(struct i387_fxsave_struct))) + if (__copy_to_user(&buf->_fxsr_env[0], fx, xstate_size)) + return -1; + return 1; +} + +static int save_i387_xsave(void __user *buf) +{ + struct task_struct *tsk = current; + struct _fpstate_ia32 __user *fx = buf; + int err = 0; + + /* + * For legacy compatible, we always set FP/SSE bits in the bit + * vector while saving the state to the user context. + * This will enable us capturing any changes(during sigreturn) to + * the FP/SSE bits by the legacy applications which don't touch + * xstate_bv in the xsave header. + * + * xsave aware applications can change the xstate_bv in the xsave + * header as well as change any contents in the memory layout. + * xrestore as part of sigreturn will capture all the changes. + */ + tsk->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; + + if (save_i387_fxsave(fx) < 0) + return -1; + + err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved_ia32, + sizeof(struct _fpx_sw_bytes)); + err |= __put_user(FP_XSTATE_MAGIC2, + (__u32 __user *) (buf + sig_xstate_ia32_size + - FP_XSTATE_MAGIC2_SIZE)); + if (err) return -1; + return 1; } -int save_i387(struct _fpstate __user *buf) +int save_i387_xstate_ia32(void __user *buf) { + struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf; + struct task_struct *tsk = current; + if (!used_math()) return 0; - /* This will cause a "finit" to be triggered by the next + if (!access_ok(VERIFY_WRITE, buf, sig_xstate_ia32_size)) + return -EACCES; + /* + * 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 { - return save_i387_soft(¤t->thread.i387.soft, buf); + if (!HAVE_HWFP) { + return fpregs_soft_get(current, NULL, + 0, sizeof(struct user_i387_ia32_struct), + NULL, fp) ? -1 : 1; } + + unlazy_fpu(tsk); + + if (cpu_has_xsave) + return save_i387_xsave(fp); + if (cpu_has_fxsr) + return save_i387_fxsave(fp); + else + return save_i387_fsave(fp); } -static inline int restore_i387_fsave(struct _fpstate __user *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, + + return __copy_from_user(&tsk->thread.xstate->fsave, buf, sizeof(struct i387_fsave_struct)); } -static int restore_i387_fxsave(struct _fpstate __user *buf) +static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf, + unsigned int size) { - int err; struct task_struct *tsk = current; - clear_fpu(tsk); - err = __copy_from_user(&tsk->thread.i387.fxsave, &buf->_fxsr_env[0], - sizeof(struct i387_fxsave_struct)); + struct user_i387_ia32_struct env; + int err; + + err = __copy_from_user(&tsk->thread.xstate->fxsave, &buf->_fxsr_env[0], + size); /* mxcsr reserved bits must be masked to zero for security reasons */ - tsk->thread.i387.fxsave.mxcsr &= mxcsr_feature_mask; - return err ? 1 : convert_fxsr_from_user(&tsk->thread.i387.fxsave, buf); + tsk->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; + if (err || __copy_from_user(&env, buf, sizeof(env))) + return 1; + convert_to_fxsr(tsk, &env); + + return 0; } -int restore_i387(struct _fpstate __user *buf) +static int restore_i387_xsave(void __user *buf) { + struct _fpx_sw_bytes fx_sw_user; + struct _fpstate_ia32 __user *fx_user = + ((struct _fpstate_ia32 __user *) buf); + struct i387_fxsave_struct __user *fx = + (struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0]; + struct xsave_hdr_struct *xsave_hdr = + ¤t->thread.xstate->xsave.xsave_hdr; + u64 mask; int err; - if (HAVE_HWFP) { - if (cpu_has_fxsr) { - err = restore_i387_fxsave(buf); - } else { - err = restore_i387_fsave(buf); - } - } else { - err = restore_i387_soft(¤t->thread.i387.soft, buf); - } - set_used_math(); - return err; -} + if (check_for_xstate(fx, buf, &fx_sw_user)) + goto fx_only; -/* - * ptrace request handlers. - */ + mask = fx_sw_user.xstate_bv; -static inline int get_fpregs_fsave(struct user_i387_struct __user *buf, - struct task_struct *tsk) -{ - return __copy_to_user(buf, &tsk->thread.i387.fsave, - sizeof(struct user_i387_struct)); -} + err = restore_i387_fxsave(buf, fx_sw_user.xstate_size); -static inline int get_fpregs_fxsave(struct user_i387_struct __user *buf, - struct task_struct *tsk) -{ - return convert_fxsr_to_user((struct _fpstate __user *)buf, - &tsk->thread.i387.fxsave); -} + xsave_hdr->xstate_bv &= pcntxt_mask; + /* + * These bits must be zero. + */ + xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0; -int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *tsk) -{ - if (HAVE_HWFP) { - if (cpu_has_fxsr) { - return get_fpregs_fxsave(buf, tsk); - } else { - return get_fpregs_fsave(buf, tsk); - } - } else { - return save_i387_soft(&tsk->thread.i387.soft, - (struct _fpstate __user *)buf); - } -} + /* + * Init the state that is not present in the memory layout + * and enabled by the OS. + */ + mask = ~(pcntxt_mask & ~mask); + xsave_hdr->xstate_bv &= mask; -static inline int set_fpregs_fsave(struct task_struct *tsk, - struct user_i387_struct __user *buf) -{ - return __copy_from_user(&tsk->thread.i387.fsave, buf, - sizeof(struct user_i387_struct)); + return err; +fx_only: + /* + * Couldn't find the extended state information in the memory + * layout. Restore the FP/SSE and init the other extended state + * enabled by the OS. + */ + xsave_hdr->xstate_bv = XSTATE_FPSSE; + return restore_i387_fxsave(buf, sizeof(struct i387_fxsave_struct)); } -static inline int set_fpregs_fxsave(struct task_struct *tsk, - struct user_i387_struct __user *buf) +int restore_i387_xstate_ia32(void __user *buf) { - return convert_fxsr_from_user(&tsk->thread.i387.fxsave, - (struct _fpstate __user *)buf); -} + int err; + struct task_struct *tsk = current; + struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf; -int set_fpregs(struct task_struct *tsk, struct user_i387_struct __user *buf) -{ - if (HAVE_HWFP) { - if (cpu_has_fxsr) { - return set_fpregs_fxsave(tsk, buf); - } else { - return set_fpregs_fsave(tsk, buf); + if (HAVE_HWFP) + clear_fpu(tsk); + + if (!buf) { + if (used_math()) { + clear_fpu(tsk); + clear_used_math(); } - } else { - return restore_i387_soft(&tsk->thread.i387.soft, - (struct _fpstate __user *)buf); - } -} -int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *tsk) -{ - if (cpu_has_fxsr) { - if (__copy_to_user(buf, &tsk->thread.i387.fxsave, - sizeof(struct user_fxsr_struct))) - return -EFAULT; return 0; - } else { - return -EIO; + } else + if (!access_ok(VERIFY_READ, buf, sig_xstate_ia32_size)) + return -EACCES; + + if (!used_math()) { + err = init_fpu(tsk); + if (err) + return err; } -} -int set_fpxregs(struct task_struct *tsk, struct user_fxsr_struct __user *buf) -{ - int ret = 0; - - if (cpu_has_fxsr) { - if (__copy_from_user(&tsk->thread.i387.fxsave, buf, - sizeof(struct user_fxsr_struct))) - ret = -EFAULT; - /* mxcsr reserved bits must be masked to zero - * for security reasons */ - tsk->thread.i387.fxsave.mxcsr &= mxcsr_feature_mask; + if (HAVE_HWFP) { + if (cpu_has_xsave) + err = restore_i387_xsave(buf); + else if (cpu_has_fxsr) + err = restore_i387_fxsave(fp, sizeof(struct + i387_fxsave_struct)); + else + err = restore_i387_fsave(fp); } else { - ret = -EIO; + err = fpregs_soft_set(current, NULL, + 0, sizeof(struct user_i387_ia32_struct), + NULL, fp) != 0; } - return ret; + set_used_math(); + + return err; } /* * FPU state for core dumps. + * This is only used for a.out dumps now. + * It is declared generically using elf_fpregset_t (which is + * struct user_i387_struct) but is in fact only used for 32-bit + * dumps, so on 64-bit it is really struct user_i387_ia32_struct. */ - -static inline void copy_fpu_fsave(struct task_struct *tsk, - struct user_i387_struct *fpu) -{ - memcpy(fpu, &tsk->thread.i387.fsave, - sizeof(struct user_i387_struct)); -} - -static inline void copy_fpu_fxsave(struct task_struct *tsk, - struct user_i387_struct *fpu) -{ - unsigned short *to; - unsigned short *from; - int i; - - memcpy(fpu, &tsk->thread.i387.fxsave, 7 * sizeof(long)); - - to = (unsigned short *)&fpu->st_space[0]; - from = (unsigned short *)&tsk->thread.i387.fxsave.st_space[0]; - for (i = 0; i < 8; i++, to += 5, from += 8) - memcpy(to, from, 5 * sizeof(unsigned short)); -} - 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) { - unlazy_fpu(tsk); - if (cpu_has_fxsr) { - copy_fpu_fxsave(tsk, fpu); - } else { - copy_fpu_fsave(tsk, fpu); - } - } + if (fpvalid) + fpvalid = !fpregs_get(tsk, NULL, + 0, sizeof(struct user_i387_ia32_struct), + fpu, NULL); return fpvalid; } EXPORT_SYMBOL(dump_fpu); -int dump_task_fpu(struct task_struct *tsk, struct user_i387_struct *fpu) -{ - int fpvalid = !!tsk_used_math(tsk); - - if (fpvalid) { - if (tsk == current) - unlazy_fpu(tsk); - if (cpu_has_fxsr) - copy_fpu_fxsave(tsk, fpu); - else - copy_fpu_fsave(tsk, fpu); - } - return fpvalid; -} - -int dump_task_extended_fpu(struct task_struct *tsk, - struct user_fxsr_struct *fpu) -{ - int fpvalid = tsk_used_math(tsk) && cpu_has_fxsr; - - if (fpvalid) { - if (tsk == current) - unlazy_fpu(tsk); - memcpy(fpu, &tsk->thread.i387.fxsave, sizeof(*fpu)); - } - return fpvalid; -} +#endif /* CONFIG_X86_32 || CONFIG_IA32_EMULATION */