[PATCH 3/3] KVM: x86: Use FPU API
From: Sheng Yang
Date: Thu May 13 2010 - 23:18:51 EST
Convert KVM to use generic FPU API.
Signed-off-by: Sheng Yang <sheng@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 18 +---------
arch/x86/kvm/x86.c | 73 ++++++++++++---------------------------
2 files changed, 23 insertions(+), 68 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ed48904..beba6f5 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -300,8 +300,7 @@ struct kvm_vcpu_arch {
unsigned long mmu_seq;
} update_pte;
- struct i387_fxsave_struct host_fx_image;
- struct i387_fxsave_struct guest_fx_image;
+ struct fpu host_fpu, guest_fpu;
gva_t mmio_fault_cr2;
struct kvm_pio_request pio;
@@ -709,21 +708,6 @@ static inline unsigned long read_msr(unsigned long msr)
}
#endif
-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 kvm_fx_finit(void)
-{
- asm("finit");
-}
-
static inline u32 get_rdx_init_val(void)
{
return 0x600; /* P6 family */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index cd8a606..2313f76 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -52,6 +52,8 @@
#include <asm/desc.h>
#include <asm/mtrr.h>
#include <asm/mce.h>
+#include <asm/i387.h>
+#include <asm/xcr.h>
#define MAX_IO_MSRS 256
#define CR0_RESERVED_BITS \
@@ -5069,27 +5071,6 @@ unlock_out:
}
/*
- * fxsave fpu state. Taken from x86_64/processor.h. To be killed when
- * we have asm/x86/processor.h
- */
-struct fxsave {
- u16 cwd;
- u16 swd;
- u16 twd;
- u16 fop;
- u64 rip;
- u64 rdp;
- u32 mxcsr;
- u32 mxcsr_mask;
- u32 st_space[32]; /* 8*16 bytes for each FP-reg = 128 bytes */
-#ifdef CONFIG_X86_64
- u32 xmm_space[64]; /* 16*16 bytes for each XMM-reg = 256 bytes */
-#else
- u32 xmm_space[32]; /* 8*16 bytes for each XMM-reg = 128 bytes */
-#endif
-};
-
-/*
* Translate a guest virtual address to a guest physical address.
*/
int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
@@ -5114,7 +5095,8 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
- struct fxsave *fxsave = (struct fxsave *)&vcpu->arch.guest_fx_image;
+ struct i387_fxsave_struct *fxsave =
+ &vcpu->arch.guest_fpu.state->fxsave;
vcpu_load(vcpu);
@@ -5134,7 +5116,8 @@ int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
- struct fxsave *fxsave = (struct fxsave *)&vcpu->arch.guest_fx_image;
+ struct i387_fxsave_struct *fxsave =
+ &vcpu->arch.guest_fpu.state->fxsave;
vcpu_load(vcpu);
@@ -5154,41 +5137,30 @@ int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
void fx_init(struct kvm_vcpu *vcpu)
{
- 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(&vcpu->arch.host_fx_image);
+ fpu_alloc(&vcpu->arch.host_fpu);
+ fpu_alloc(&vcpu->arch.guest_fpu);
- /* Initialize guest FPU by resetting ours and saving into guest's */
- preempt_disable();
- kvm_fx_save(&vcpu->arch.host_fx_image);
- kvm_fx_finit();
- kvm_fx_save(&vcpu->arch.guest_fx_image);
- kvm_fx_restore(&vcpu->arch.host_fx_image);
- preempt_enable();
+ fpu_save(&vcpu->arch.host_fpu);
+ fpu_finit(&vcpu->arch.guest_fpu);
vcpu->arch.cr0 |= X86_CR0_ET;
- after_mxcsr_mask = offsetof(struct i387_fxsave_struct, st_space);
- vcpu->arch.guest_fx_image.mxcsr = 0x1f80;
- memset((void *)&vcpu->arch.guest_fx_image + after_mxcsr_mask,
- 0, sizeof(struct i387_fxsave_struct) - after_mxcsr_mask);
}
EXPORT_SYMBOL_GPL(fx_init);
+static void fx_free(struct kvm_vcpu *vcpu)
+{
+ fpu_free(&vcpu->arch.host_fpu);
+ fpu_free(&vcpu->arch.guest_fpu);
+}
+
void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
{
if (vcpu->guest_fpu_loaded)
return;
vcpu->guest_fpu_loaded = 1;
- kvm_fx_save(&vcpu->arch.host_fx_image);
- kvm_fx_restore(&vcpu->arch.guest_fx_image);
+ fpu_save(&vcpu->arch.host_fpu);
+ fpu_restore_checking(&vcpu->arch.guest_fpu);
trace_kvm_fpu(1);
}
@@ -5198,8 +5170,8 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
return;
vcpu->guest_fpu_loaded = 0;
- kvm_fx_save(&vcpu->arch.guest_fx_image);
- kvm_fx_restore(&vcpu->arch.host_fx_image);
+ fpu_save(&vcpu->arch.guest_fpu);
+ fpu_restore_checking(&vcpu->arch.host_fpu);
++vcpu->stat.fpu_reload;
set_bit(KVM_REQ_DEACTIVATE_FPU, &vcpu->requests);
trace_kvm_fpu(0);
@@ -5212,6 +5184,7 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
vcpu->arch.time_page = NULL;
}
+ fx_free(vcpu);
kvm_x86_ops->vcpu_free(vcpu);
}
@@ -5225,9 +5198,6 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
int r;
- /* We do fxsave: this must be aligned. */
- BUG_ON((unsigned long)&vcpu->arch.host_fx_image & 0xF);
-
vcpu->arch.mtrr_state.have_fixed = 1;
vcpu_load(vcpu);
r = kvm_arch_vcpu_reset(vcpu);
@@ -5249,6 +5219,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
kvm_mmu_unload(vcpu);
vcpu_put(vcpu);
+ fx_free(vcpu);
kvm_x86_ops->vcpu_free(vcpu);
}
--
1.7.0.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/