On 1/10/2016 8:32 AM, Christoffer Dall wrote: > On Tue, Jan 05, 2016 at 11:28:18AM -0800, Mario Smarduch wrote: >> >> >> On 1/5/2016 7:00 AM, Christoffer Dall wrote: >>> On Sat, Dec 26, 2015 at 01:54:55PM -0800, Mario Smarduch wrote: >>>> Add helper functions to enable access to fp/smid on guest entry and save host >>>> fpexc on vcpu put, check if fp/simd registers are dirty and add new vcpu >>>> fields. >>>> >>>> Signed-off-by: Mario Smarduch <m.smarduch@xxxxxxxxxxx> >>>> --- >>>> arch/arm/include/asm/kvm_emulate.h | 42 ++++++++++++++++++++++++++++++++++++ >>>> arch/arm/include/asm/kvm_host.h | 6 ++++++ >>>> arch/arm64/include/asm/kvm_emulate.h | 8 +++++++ >>>> 3 files changed, 56 insertions(+) >>>> >>>> diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h >>>> index 3095df0..d4d9da1 100644 >>>> --- a/arch/arm/include/asm/kvm_emulate.h >>>> +++ b/arch/arm/include/asm/kvm_emulate.h >>>> @@ -24,6 +24,8 @@ >>>> #include <asm/kvm_mmio.h> >>>> #include <asm/kvm_arm.h> >>>> #include <asm/cputype.h> >>>> +#include <asm/vfp.h> >>>> +#include "../vfp/vfpinstr.h" >>> >>> this looks dodgy... >>> >>> can you move vfpinstr.h instead? >> Sure I'll fix it up, it's in couple other places in kernel and kvm >> - copied it. >>> >>>> >>>> unsigned long *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num); >>>> unsigned long *vcpu_spsr(struct kvm_vcpu *vcpu); >>>> @@ -255,4 +257,44 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu, >>>> } >>>> } >>>> >>>> +#ifdef CONFIG_VFPv3 >>>> +/* Called from vcpu_load - save fpexc and enable guest access to fp/simd unit */ >>> >>> the comment is misleading, you're not enabling guest access to the >>> fp/simd unit, you're just setting the enabled bit to ensure guest >>> accesses trap. >> >> That's more accurate. >>> >>>> +static inline void vcpu_trap_vfp_enable(struct kvm_vcpu *vcpu) >>>> +{ >>>> + u32 fpexc; >>>> + >>>> + /* Save host fpexc, and enable guest access to fp unit */ >>>> + fpexc = fmrx(FPEXC); >>>> + vcpu->arch.host_fpexc = fpexc; >>>> + fpexc |= FPEXC_EN; >>>> + fmxr(FPEXC, fpexc); >>>> + >>>> + /* Configure HCPTR to trap on tracing and fp/simd access */ >>>> + vcpu->arch.hcptr = HCPTR_TTA | HCPTR_TCP(10) | HCPTR_TCP(11); >>>> +} >>>> + >>>> +/* Called from vcpu_put - restore host fpexc */ >>> >>> I would probably get rid of the "Called from" stuff and just describe >>> what these functions do locally. Comments like this are likely to be >>> out of date soon'ish. >> >> Yeah true, will do. >>> >>>> +static inline void vcpu_restore_host_fpexc(struct kvm_vcpu *vcpu) >>>> +{ >>>> + fmxr(FPEXC, vcpu->arch.host_fpexc); >>>> +} >>>> + >>>> +/* If trap bits are reset then fp/simd registers are dirty */ >>>> +static inline bool vcpu_vfp_isdirty(struct kvm_vcpu *vcpu) >>>> +{ >>>> + return !(vcpu->arch.hcptr & (HCPTR_TCP(10) | HCPTR_TCP(11))); >>>> +} >>>> +#else >>>> +static inline void vcpu_trap_vfp_enable(struct kvm_vcpu *vcpu) >>>> +{ >>>> + vcpu->arch.hcptr = HCPTR_TTA; >>>> +} >>>> + >>>> +static inline void vcpu_restore_host_fpexc(struct kvm_vcpu *vcpu) {} >>>> +static inline bool vcpu_vfp_isdirty(struct kvm_vcpu *vcpu) >>>> +{ >>>> + return false; >>>> +} >>>> +#endif >>> >>> this kind of feels like it belongs in its own C-file instead of a header >>> file, perhaps arch/arm/kvm/vfp.C. >>> >>> Marc, what do you think? >>> >> >> That would be starting from vcpu_trap_vfp_enable()? The file is getting >> little overloaded. > > yes, starting from vcpu_trap_vfp_enable. > > Which file is getting overloaded? > > I'm thinking the assembly file you add in the next patch could be > inline assembly in a C-file combined with this code, perhaps. Yes that makes sense, I'll convert it. > >> >> I'm also thinking that 3rd patch should have one function call for vcpu_put >> like vcpu_load does instead of exposing arm32/arm64, arm32 only relevant logic. >> When you have a chance to review that patch please keep that in mind. >> > > ok, will try ;) > > -Christoffer > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html