>From 95be2b1ac41a40f2f3d581f0674b25ca4b70a025 Mon Sep 17 00:00:00 2001 From: Zachary Amsden Date: Tue, 25 May 2010 16:32:14 -1000 Subject: [PATCH 2/5] Extend module compatability to FPU code Signed-off-by: Zachary Amsden --- x86/external-module-compat.h | 84 ++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 84 insertions(+), 0 deletions(-) diff --git a/x86/external-module-compat.h b/x86/external-module-compat.h index 09bf232..316f7ff 100644 --- a/x86/external-module-compat.h +++ b/x86/external-module-compat.h @@ -788,3 +788,87 @@ struct kvm_pvclock_vcpu_time_info { #else #define kvm_pvclock_vcpu_time_info pvclock_vcpu_time_info #endif + +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,34) +#include +#include +struct _fpu { + struct i387_fxsave_struct fxsave; + struct i387_fxsave_struct host_fx_image; +}; + +struct fpu { + struct _fpu *state; + struct _fpu state_static; +}; + +static inline bool fpu_allocated(struct fpu *fpu) +{ + fpu->state = &fpu->state_static; + return true; +} + +static inline int fpu_alloc(struct fpu *fpu) +{ + fpu->state = &fpu->state_static; + return 0; +} + +static inline void fpu_free(struct fpu *fpu) +{ +} + +static inline void kvm_fx_finit(void) +{ + asm("finit"); +} + +static inline void kvm_fx_save(struct i387_fxsave_struct *image) +{ + asm("fxsave (%0)":: "r" (image)); +} + +static inline void kvm_fx_restore(struct i387_fxsave_struct *image) +{ + asm("fxrstor (%0)":: "r" (image)); +} + +static inline void fpu_finit(struct fpu *fpu) +{ + unsigned after_mxcsr_mask; + + /* + * Touch the fpu the first time in non atomic context as if + * this is the first fpu instruction the exception handler + * will fire before the instruction returns and it'll have to + * allocate ram with GFP_KERNEL. + */ + if (!used_math()) + kvm_fx_save(&fpu->state->host_fx_image); + + /* Initialize guest FPU by resetting ours and saving into guest's */ + preempt_disable(); + kvm_fx_save(&fpu->state->host_fx_image); + kvm_fx_finit(); + kvm_fx_save(&fpu->state->fxsave); + kvm_fx_restore(&fpu->state->host_fx_image); + preempt_enable(); + + after_mxcsr_mask = offsetof(struct i387_fxsave_struct, st_space); + fpu->state->fxsave.mxcsr = 0x1f80; + memset((void *)&fpu->state->fxsave + after_mxcsr_mask, + 0, sizeof(struct i387_fxsave_struct) - after_mxcsr_mask); +} + +static inline void fpu_restore_checking(struct fpu *fpu) +{ + kvm_fx_save(&fpu->state->host_fx_image); + kvm_fx_restore(&fpu->state->fxsave); +} + +static inline void fpu_save_init(struct fpu *fpu) +{ + kvm_fx_save(&fpu->state->fxsave); + kvm_fx_restore(&fpu->state->host_fx_image); +} +#endif -- 1.7.0.1