| Message ID | 20171207170630.592-22-christoffer.dall@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/12/17 17:06, Christoffer Dall wrote: > We currently handle 32-bit accesses to trapped VM system registers using > the 32-bit index into the coproc array on the vcpu structure, which is a > union of the coproc array and the sysreg array. > > Since all the 32-bit coproc indicies are created to correspond to the indices? > architectural mapping between 64-bit system registers and 32-bit > coprocessor registers, and because the AArch64 system registers are the > double in size of the AArch32 coprocessor registers, we can always find > the system register entry that we must update by dividing the 32-bit > coproc index by 2. > > This is going to make our lives much easier when we have to start > accessing system registers that use deferred save/restore and might > have to be read directly from the physical CPU. > > Reviewed-by: Andrew Jones <drjones@redhat.com> > Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> > --- > arch/arm64/include/asm/kvm_host.h | 8 -------- > arch/arm64/kvm/sys_regs.c | 20 +++++++++++++++----- > 2 files changed, 15 insertions(+), 13 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index c841eeeeb5c5..de0d55b30b61 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -290,14 +290,6 @@ struct kvm_vcpu_arch { > #define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r)]) > #define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r)]) > > -#ifdef CONFIG_CPU_BIG_ENDIAN > -#define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r)) > -#define vcpu_cp15_64_low(v,r) vcpu_cp15((v),(r) + 1) > -#else > -#define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r) + 1) > -#define vcpu_cp15_64_low(v,r) vcpu_cp15((v),(r)) > -#endif > - > struct kvm_vm_stat { > ulong remote_tlb_flush; > }; > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index 1830ebc227d1..62c12ab9e6c4 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -121,16 +121,26 @@ static bool access_vm_reg(struct kvm_vcpu *vcpu, > const struct sys_reg_desc *r) > { > bool was_enabled = vcpu_has_cache_enabled(vcpu); > + u64 val; > + int reg = r->reg; > > BUG_ON(!p->is_write); > > - if (!p->is_aarch32) { > - vcpu_sys_reg(vcpu, r->reg) = p->regval; > + /* See the 32bit mapping in kvm_host.h */ > + if (p->is_aarch32) > + reg = r->reg / 2; > + > + if (!p->is_aarch32 || !p->is_32bit) { > + val = p->regval; > } else { > - if (!p->is_32bit) > - vcpu_cp15_64_high(vcpu, r->reg) = upper_32_bits(p->regval); > - vcpu_cp15_64_low(vcpu, r->reg) = lower_32_bits(p->regval); > + val = vcpu_sys_reg(vcpu, reg); > + if (r->reg % 2) > + val = (p->regval << 32) | (u64)lower_32_bits(val); > + else > + val = ((u64)upper_32_bits(val) << 32) | > + (u64)lower_32_bits(p->regval); Nit: the u64 casts on lower_32_bits are superfluous. > } > + vcpu_sys_reg(vcpu, reg) = val; > > kvm_toggle_cache(vcpu, was_enabled); > return true; > Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> M.
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index c841eeeeb5c5..de0d55b30b61 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -290,14 +290,6 @@ struct kvm_vcpu_arch { #define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r)]) #define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r)]) -#ifdef CONFIG_CPU_BIG_ENDIAN -#define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r)) -#define vcpu_cp15_64_low(v,r) vcpu_cp15((v),(r) + 1) -#else -#define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r) + 1) -#define vcpu_cp15_64_low(v,r) vcpu_cp15((v),(r)) -#endif - struct kvm_vm_stat { ulong remote_tlb_flush; }; diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 1830ebc227d1..62c12ab9e6c4 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -121,16 +121,26 @@ static bool access_vm_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { bool was_enabled = vcpu_has_cache_enabled(vcpu); + u64 val; + int reg = r->reg; BUG_ON(!p->is_write); - if (!p->is_aarch32) { - vcpu_sys_reg(vcpu, r->reg) = p->regval; + /* See the 32bit mapping in kvm_host.h */ + if (p->is_aarch32) + reg = r->reg / 2; + + if (!p->is_aarch32 || !p->is_32bit) { + val = p->regval; } else { - if (!p->is_32bit) - vcpu_cp15_64_high(vcpu, r->reg) = upper_32_bits(p->regval); - vcpu_cp15_64_low(vcpu, r->reg) = lower_32_bits(p->regval); + val = vcpu_sys_reg(vcpu, reg); + if (r->reg % 2) + val = (p->regval << 32) | (u64)lower_32_bits(val); + else + val = ((u64)upper_32_bits(val) << 32) | + (u64)lower_32_bits(p->regval); } + vcpu_sys_reg(vcpu, reg) = val; kvm_toggle_cache(vcpu, was_enabled); return true;