x86/fpu: Factor out the FPU regset code into fpu/regset.c
So much of fpu/core.c is the regset code, but it just obscures the generic FPU state machine logic. Factor out the regset code into fpu/regset.c, where it can be read in isolation. This affects one API: fpu__activate_stopped() has to be made available from the core to fpu/regset.c. No change in functionality. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar
parent
b992c660d3
commit
0c306bcfba
4 changed files with 360 additions and 354 deletions
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@ -29,8 +29,6 @@ extern void fpu__init_system_xstate(void);
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extern void fpu__init_cpu_xstate(void);
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extern void fpu__init_system(struct cpuinfo_x86 *c);
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extern void fpu__activate_curr(struct fpu *fpu);
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extern void fpstate_init(union thread_xstate *state);
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#ifdef CONFIG_MATH_EMULATION
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extern void fpstate_init_soft(struct i387_soft_struct *soft);
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@ -49,6 +47,8 @@ extern int fpu__exception_code(struct fpu *fpu, int trap_nr);
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/*
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* High level FPU state handling functions:
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*/
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extern void fpu__activate_curr(struct fpu *fpu);
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extern void fpu__activate_stopped(struct fpu *fpu);
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extern void fpu__save(struct fpu *fpu);
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extern void fpu__restore(void);
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extern int fpu__restore_sig(void __user *buf, int ia32_frame);
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@ -2,4 +2,4 @@
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# Build rules for the FPU support code:
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#
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obj-y += init.o bugs.o core.o signal.o xstate.o
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obj-y += init.o bugs.o core.o regset.o signal.o xstate.o
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@ -320,7 +320,7 @@ EXPORT_SYMBOL_GPL(fpu__activate_curr);
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* the read-only case, it's not strictly necessary for
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* read-only access to the context.
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*/
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static void fpu__activate_stopped(struct fpu *child_fpu)
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void fpu__activate_stopped(struct fpu *child_fpu)
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{
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WARN_ON_ONCE(child_fpu == ¤t->thread.fpu);
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@ -425,356 +425,6 @@ void fpu__clear(struct fpu *fpu)
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}
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}
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/*
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* The xstateregs_active() routine is the same as the regset_fpregs_active() routine,
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* as the "regset->n" for the xstate regset will be updated based on the feature
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* capabilites supported by the xsave.
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*/
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int regset_fpregs_active(struct task_struct *target, const struct user_regset *regset)
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{
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struct fpu *target_fpu = &target->thread.fpu;
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return target_fpu->fpstate_active ? regset->n : 0;
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}
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int regset_xregset_fpregs_active(struct task_struct *target, const struct user_regset *regset)
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{
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struct fpu *target_fpu = &target->thread.fpu;
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return (cpu_has_fxsr && target_fpu->fpstate_active) ? regset->n : 0;
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}
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int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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void *kbuf, void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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if (!cpu_has_fxsr)
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return -ENODEV;
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fpu__activate_stopped(fpu);
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fpstate_sanitize_xstate(fpu);
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return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
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&fpu->state.fxsave, 0, -1);
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}
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int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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const void *kbuf, const void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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int ret;
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if (!cpu_has_fxsr)
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return -ENODEV;
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fpu__activate_stopped(fpu);
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fpstate_sanitize_xstate(fpu);
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ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
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&fpu->state.fxsave, 0, -1);
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/*
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* mxcsr reserved bits must be masked to zero for security reasons.
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*/
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fpu->state.fxsave.mxcsr &= mxcsr_feature_mask;
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/*
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* update the header bits in the xsave header, indicating the
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* presence of FP and SSE state.
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*/
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if (cpu_has_xsave)
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fpu->state.xsave.header.xfeatures |= XSTATE_FPSSE;
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return ret;
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}
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int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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void *kbuf, void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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struct xsave_struct *xsave;
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int ret;
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if (!cpu_has_xsave)
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return -ENODEV;
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fpu__activate_stopped(fpu);
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xsave = &fpu->state.xsave;
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/*
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* Copy the 48bytes defined by the software first into the xstate
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* memory layout in the thread struct, so that we can copy the entire
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* xstateregs to the user using one user_regset_copyout().
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*/
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memcpy(&xsave->i387.sw_reserved,
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xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes));
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/*
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* Copy the xstate memory layout.
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*/
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ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
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return ret;
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}
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int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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const void *kbuf, const void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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struct xsave_struct *xsave;
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int ret;
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if (!cpu_has_xsave)
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return -ENODEV;
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fpu__activate_stopped(fpu);
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xsave = &fpu->state.xsave;
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ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
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/*
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* mxcsr reserved bits must be masked to zero for security reasons.
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*/
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xsave->i387.mxcsr &= mxcsr_feature_mask;
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xsave->header.xfeatures &= xfeatures_mask;
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/*
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* These bits must be zero.
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*/
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memset(&xsave->header.reserved, 0, 48);
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return ret;
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}
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#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
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/*
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* FPU tag word conversions.
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*/
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static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
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{
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unsigned int tmp; /* to avoid 16 bit prefixes in the code */
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/* Transform each pair of bits into 01 (valid) or 00 (empty) */
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tmp = ~twd;
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tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
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/* and move the valid bits to the lower byte. */
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tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
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tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
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tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
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return tmp;
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}
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#define FPREG_ADDR(f, n) ((void *)&(f)->st_space + (n) * 16)
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#define FP_EXP_TAG_VALID 0
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#define FP_EXP_TAG_ZERO 1
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#define FP_EXP_TAG_SPECIAL 2
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#define FP_EXP_TAG_EMPTY 3
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static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave)
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{
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struct _fpxreg *st;
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u32 tos = (fxsave->swd >> 11) & 7;
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u32 twd = (unsigned long) fxsave->twd;
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u32 tag;
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u32 ret = 0xffff0000u;
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int i;
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for (i = 0; i < 8; i++, twd >>= 1) {
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if (twd & 0x1) {
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st = FPREG_ADDR(fxsave, (i - tos) & 7);
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switch (st->exponent & 0x7fff) {
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case 0x7fff:
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tag = FP_EXP_TAG_SPECIAL;
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break;
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case 0x0000:
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if (!st->significand[0] &&
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!st->significand[1] &&
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!st->significand[2] &&
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!st->significand[3])
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tag = FP_EXP_TAG_ZERO;
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else
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tag = FP_EXP_TAG_SPECIAL;
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break;
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default:
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if (st->significand[3] & 0x8000)
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tag = FP_EXP_TAG_VALID;
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else
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tag = FP_EXP_TAG_SPECIAL;
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break;
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}
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} else {
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tag = FP_EXP_TAG_EMPTY;
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}
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ret |= tag << (2 * i);
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}
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return ret;
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}
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/*
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* FXSR floating point environment conversions.
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*/
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void
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convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk)
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{
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struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state.fxsave;
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struct _fpreg *to = (struct _fpreg *) &env->st_space[0];
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struct _fpxreg *from = (struct _fpxreg *) &fxsave->st_space[0];
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int i;
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env->cwd = fxsave->cwd | 0xffff0000u;
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env->swd = fxsave->swd | 0xffff0000u;
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env->twd = twd_fxsr_to_i387(fxsave);
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#ifdef CONFIG_X86_64
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env->fip = fxsave->rip;
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env->foo = fxsave->rdp;
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/*
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* should be actually ds/cs at fpu exception time, but
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* that information is not available in 64bit mode.
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*/
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env->fcs = task_pt_regs(tsk)->cs;
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if (tsk == current) {
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savesegment(ds, env->fos);
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} else {
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env->fos = tsk->thread.ds;
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}
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env->fos |= 0xffff0000;
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#else
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env->fip = fxsave->fip;
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env->fcs = (u16) fxsave->fcs | ((u32) fxsave->fop << 16);
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env->foo = fxsave->foo;
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env->fos = fxsave->fos;
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#endif
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for (i = 0; i < 8; ++i)
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memcpy(&to[i], &from[i], sizeof(to[0]));
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}
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void convert_to_fxsr(struct task_struct *tsk,
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const struct user_i387_ia32_struct *env)
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{
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struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state.fxsave;
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struct _fpreg *from = (struct _fpreg *) &env->st_space[0];
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struct _fpxreg *to = (struct _fpxreg *) &fxsave->st_space[0];
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int i;
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fxsave->cwd = env->cwd;
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fxsave->swd = env->swd;
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fxsave->twd = twd_i387_to_fxsr(env->twd);
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fxsave->fop = (u16) ((u32) env->fcs >> 16);
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#ifdef CONFIG_X86_64
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fxsave->rip = env->fip;
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fxsave->rdp = env->foo;
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/* cs and ds ignored */
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#else
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fxsave->fip = env->fip;
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fxsave->fcs = (env->fcs & 0xffff);
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fxsave->foo = env->foo;
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fxsave->fos = env->fos;
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#endif
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for (i = 0; i < 8; ++i)
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memcpy(&to[i], &from[i], sizeof(from[0]));
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}
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int fpregs_get(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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void *kbuf, void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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struct user_i387_ia32_struct env;
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fpu__activate_stopped(fpu);
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if (!static_cpu_has(X86_FEATURE_FPU))
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return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf);
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if (!cpu_has_fxsr)
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return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
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&fpu->state.fsave, 0,
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-1);
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fpstate_sanitize_xstate(fpu);
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if (kbuf && pos == 0 && count == sizeof(env)) {
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convert_from_fxsr(kbuf, target);
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return 0;
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}
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convert_from_fxsr(&env, target);
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return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1);
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}
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int fpregs_set(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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const void *kbuf, const void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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struct user_i387_ia32_struct env;
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int ret;
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fpu__activate_stopped(fpu);
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fpstate_sanitize_xstate(fpu);
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if (!static_cpu_has(X86_FEATURE_FPU))
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return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf);
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if (!cpu_has_fxsr)
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return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
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&fpu->state.fsave, 0,
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-1);
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if (pos > 0 || count < sizeof(env))
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convert_from_fxsr(&env, target);
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ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &env, 0, -1);
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if (!ret)
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convert_to_fxsr(target, &env);
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/*
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* update the header bit in the xsave header, indicating the
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* presence of FP.
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*/
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if (cpu_has_xsave)
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fpu->state.xsave.header.xfeatures |= XSTATE_FP;
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return ret;
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}
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/*
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* FPU state for core dumps.
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* This is only used for a.out dumps now.
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* It is declared generically using elf_fpregset_t (which is
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* struct user_i387_struct) but is in fact only used for 32-bit
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* dumps, so on 64-bit it is really struct user_i387_ia32_struct.
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*/
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int dump_fpu(struct pt_regs *regs, struct user_i387_struct *ufpu)
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{
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struct task_struct *tsk = current;
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struct fpu *fpu = &tsk->thread.fpu;
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int fpvalid;
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fpvalid = fpu->fpstate_active;
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if (fpvalid)
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fpvalid = !fpregs_get(tsk, NULL,
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0, sizeof(struct user_i387_ia32_struct),
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ufpu, NULL);
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return fpvalid;
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}
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EXPORT_SYMBOL(dump_fpu);
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#endif /* CONFIG_X86_32 || CONFIG_IA32_EMULATION */
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/*
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* x87 math exception handling:
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*/
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356
arch/x86/kernel/fpu/regset.c
Normal file
356
arch/x86/kernel/fpu/regset.c
Normal file
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@ -0,0 +1,356 @@
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/*
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* FPU register's regset abstraction, for ptrace, core dumps, etc.
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*/
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#include <asm/fpu/internal.h>
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#include <asm/fpu/signal.h>
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#include <asm/fpu/regset.h>
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/*
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* The xstateregs_active() routine is the same as the regset_fpregs_active() routine,
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* as the "regset->n" for the xstate regset will be updated based on the feature
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* capabilites supported by the xsave.
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*/
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int regset_fpregs_active(struct task_struct *target, const struct user_regset *regset)
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{
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struct fpu *target_fpu = &target->thread.fpu;
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return target_fpu->fpstate_active ? regset->n : 0;
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}
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int regset_xregset_fpregs_active(struct task_struct *target, const struct user_regset *regset)
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{
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struct fpu *target_fpu = &target->thread.fpu;
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return (cpu_has_fxsr && target_fpu->fpstate_active) ? regset->n : 0;
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}
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int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
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unsigned int pos, unsigned int count,
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void *kbuf, void __user *ubuf)
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{
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struct fpu *fpu = &target->thread.fpu;
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if (!cpu_has_fxsr)
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return -ENODEV;
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fpu__activate_stopped(fpu);
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fpstate_sanitize_xstate(fpu);
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return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
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&fpu->state.fxsave, 0, -1);
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}
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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)
|
||||
{
|
||||
struct fpu *fpu = &target->thread.fpu;
|
||||
int ret;
|
||||
|
||||
if (!cpu_has_fxsr)
|
||||
return -ENODEV;
|
||||
|
||||
fpu__activate_stopped(fpu);
|
||||
fpstate_sanitize_xstate(fpu);
|
||||
|
||||
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
|
||||
&fpu->state.fxsave, 0, -1);
|
||||
|
||||
/*
|
||||
* mxcsr reserved bits must be masked to zero for security reasons.
|
||||
*/
|
||||
fpu->state.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)
|
||||
fpu->state.xsave.header.xfeatures |= 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)
|
||||
{
|
||||
struct fpu *fpu = &target->thread.fpu;
|
||||
struct xsave_struct *xsave;
|
||||
int ret;
|
||||
|
||||
if (!cpu_has_xsave)
|
||||
return -ENODEV;
|
||||
|
||||
fpu__activate_stopped(fpu);
|
||||
|
||||
xsave = &fpu->state.xsave;
|
||||
|
||||
/*
|
||||
* 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(&xsave->i387.sw_reserved,
|
||||
xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes));
|
||||
/*
|
||||
* Copy the xstate memory layout.
|
||||
*/
|
||||
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, 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)
|
||||
{
|
||||
struct fpu *fpu = &target->thread.fpu;
|
||||
struct xsave_struct *xsave;
|
||||
int ret;
|
||||
|
||||
if (!cpu_has_xsave)
|
||||
return -ENODEV;
|
||||
|
||||
fpu__activate_stopped(fpu);
|
||||
|
||||
xsave = &fpu->state.xsave;
|
||||
|
||||
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
|
||||
/*
|
||||
* mxcsr reserved bits must be masked to zero for security reasons.
|
||||
*/
|
||||
xsave->i387.mxcsr &= mxcsr_feature_mask;
|
||||
xsave->header.xfeatures &= xfeatures_mask;
|
||||
/*
|
||||
* These bits must be zero.
|
||||
*/
|
||||
memset(&xsave->header.reserved, 0, 48);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
|
||||
|
||||
/*
|
||||
* FPU tag word conversions.
|
||||
*/
|
||||
|
||||
static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
|
||||
{
|
||||
unsigned int tmp; /* to avoid 16 bit prefixes in the code */
|
||||
|
||||
/* Transform each pair of bits into 01 (valid) or 00 (empty) */
|
||||
tmp = ~twd;
|
||||
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 */
|
||||
tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
|
||||
|
||||
return tmp;
|
||||
}
|
||||
|
||||
#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++, twd >>= 1) {
|
||||
if (twd & 0x1) {
|
||||
st = FPREG_ADDR(fxsave, (i - tos) & 7);
|
||||
|
||||
switch (st->exponent & 0x7fff) {
|
||||
case 0x7fff:
|
||||
tag = FP_EXP_TAG_SPECIAL;
|
||||
break;
|
||||
case 0x0000:
|
||||
if (!st->significand[0] &&
|
||||
!st->significand[1] &&
|
||||
!st->significand[2] &&
|
||||
!st->significand[3])
|
||||
tag = FP_EXP_TAG_ZERO;
|
||||
else
|
||||
tag = FP_EXP_TAG_SPECIAL;
|
||||
break;
|
||||
default:
|
||||
if (st->significand[3] & 0x8000)
|
||||
tag = FP_EXP_TAG_VALID;
|
||||
else
|
||||
tag = FP_EXP_TAG_SPECIAL;
|
||||
break;
|
||||
}
|
||||
} else {
|
||||
tag = FP_EXP_TAG_EMPTY;
|
||||
}
|
||||
ret |= tag << (2 * i);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* FXSR floating point environment conversions.
|
||||
*/
|
||||
|
||||
void
|
||||
convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk)
|
||||
{
|
||||
struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state.fxsave;
|
||||
struct _fpreg *to = (struct _fpreg *) &env->st_space[0];
|
||||
struct _fpxreg *from = (struct _fpxreg *) &fxsave->st_space[0];
|
||||
int i;
|
||||
|
||||
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;
|
||||
/*
|
||||
* should be actually ds/cs at fpu exception time, but
|
||||
* that information is not available in 64bit mode.
|
||||
*/
|
||||
env->fcs = task_pt_regs(tsk)->cs;
|
||||
if (tsk == current) {
|
||||
savesegment(ds, env->fos);
|
||||
} else {
|
||||
env->fos = tsk->thread.ds;
|
||||
}
|
||||
env->fos |= 0xffff0000;
|
||||
#else
|
||||
env->fip = fxsave->fip;
|
||||
env->fcs = (u16) fxsave->fcs | ((u32) fxsave->fop << 16);
|
||||
env->foo = fxsave->foo;
|
||||
env->fos = fxsave->fos;
|
||||
#endif
|
||||
|
||||
for (i = 0; i < 8; ++i)
|
||||
memcpy(&to[i], &from[i], sizeof(to[0]));
|
||||
}
|
||||
|
||||
void convert_to_fxsr(struct task_struct *tsk,
|
||||
const struct user_i387_ia32_struct *env)
|
||||
|
||||
{
|
||||
struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state.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]));
|
||||
}
|
||||
|
||||
int fpregs_get(struct task_struct *target, const struct user_regset *regset,
|
||||
unsigned int pos, unsigned int count,
|
||||
void *kbuf, void __user *ubuf)
|
||||
{
|
||||
struct fpu *fpu = &target->thread.fpu;
|
||||
struct user_i387_ia32_struct env;
|
||||
|
||||
fpu__activate_stopped(fpu);
|
||||
|
||||
if (!static_cpu_has(X86_FEATURE_FPU))
|
||||
return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf);
|
||||
|
||||
if (!cpu_has_fxsr)
|
||||
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
|
||||
&fpu->state.fsave, 0,
|
||||
-1);
|
||||
|
||||
fpstate_sanitize_xstate(fpu);
|
||||
|
||||
if (kbuf && pos == 0 && count == sizeof(env)) {
|
||||
convert_from_fxsr(kbuf, target);
|
||||
return 0;
|
||||
}
|
||||
|
||||
convert_from_fxsr(&env, target);
|
||||
|
||||
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1);
|
||||
}
|
||||
|
||||
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)
|
||||
{
|
||||
struct fpu *fpu = &target->thread.fpu;
|
||||
struct user_i387_ia32_struct env;
|
||||
int ret;
|
||||
|
||||
fpu__activate_stopped(fpu);
|
||||
fpstate_sanitize_xstate(fpu);
|
||||
|
||||
if (!static_cpu_has(X86_FEATURE_FPU))
|
||||
return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf);
|
||||
|
||||
if (!cpu_has_fxsr)
|
||||
return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
|
||||
&fpu->state.fsave, 0,
|
||||
-1);
|
||||
|
||||
if (pos > 0 || count < sizeof(env))
|
||||
convert_from_fxsr(&env, target);
|
||||
|
||||
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &env, 0, -1);
|
||||
if (!ret)
|
||||
convert_to_fxsr(target, &env);
|
||||
|
||||
/*
|
||||
* update the header bit in the xsave header, indicating the
|
||||
* presence of FP.
|
||||
*/
|
||||
if (cpu_has_xsave)
|
||||
fpu->state.xsave.header.xfeatures |= XSTATE_FP;
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* 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.
|
||||
*/
|
||||
int dump_fpu(struct pt_regs *regs, struct user_i387_struct *ufpu)
|
||||
{
|
||||
struct task_struct *tsk = current;
|
||||
struct fpu *fpu = &tsk->thread.fpu;
|
||||
int fpvalid;
|
||||
|
||||
fpvalid = fpu->fpstate_active;
|
||||
if (fpvalid)
|
||||
fpvalid = !fpregs_get(tsk, NULL,
|
||||
0, sizeof(struct user_i387_ia32_struct),
|
||||
ufpu, NULL);
|
||||
|
||||
return fpvalid;
|
||||
}
|
||||
EXPORT_SYMBOL(dump_fpu);
|
||||
|
||||
#endif /* CONFIG_X86_32 || CONFIG_IA32_EMULATION */
|
||||
Loading…
Reference in a new issue