KVM: arm64: Move AArch32 exceptions over to AArch64 sysregs

The use of the AArch32-specific accessors have always been a bit
annoying on 64bit, and it is time for a change.

Let's move the AArch32 exception injection over to the AArch64 encoding,
which requires us to split the two halves of FAR_EL1 into DFAR and IFAR.
This enables us to drop the preempt_disable() games on VHE, and to kill
the last user of the vcpu_cp15() macro.

Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 803cb2427b54142a5865181c0ee0c893b06afadc..c905c3fcaaa0656590370ec845a663cd7e7b4a9a 100644 (file)
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -562,7 +562,6 @@ static inline bool __vcpu_write_sys_reg_to_cpu(u64 val, int reg)
 #define CPx_BIAS               IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)
 
 #define vcpu_cp14(v,r)         ((v)->arch.ctxt.copro[(r) ^ CPx_BIAS])
-#define vcpu_cp15(v,r)         ((v)->arch.ctxt.copro[(r) ^ CPx_BIAS])
 
 struct kvm_vm_stat {
        ulong remote_tlb_flush;

diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c
index e2a2e48ca371e6b1cafec6d1b126291e2d335b15..b47df73e98d782a55192051c9f3e537ddfd10941 100644 (file)
--- a/arch/arm64/kvm/inject_fault.c
+++ b/arch/arm64/kvm/inject_fault.c
@@ -69,26 +69,7 @@ static void inject_undef64(struct kvm_vcpu *vcpu)
 #define DFSR_FSC_EXTABT_LPAE   0x10
 #define DFSR_FSC_EXTABT_nLPAE  0x08
 #define DFSR_LPAE              BIT(9)
-
-static bool pre_fault_synchronize(struct kvm_vcpu *vcpu)
-{
-       preempt_disable();
-       if (vcpu->arch.sysregs_loaded_on_cpu) {
-               kvm_arch_vcpu_put(vcpu);
-               return true;
-       }
-
-       preempt_enable();
-       return false;
-}
-
-static void post_fault_synchronize(struct kvm_vcpu *vcpu, bool loaded)
-{
-       if (loaded) {
-               kvm_arch_vcpu_load(vcpu, smp_processor_id());
-               preempt_enable();
-       }
-}
+#define TTBCR_EAE              BIT(31)
 
 static void inject_undef32(struct kvm_vcpu *vcpu)
 {
@@ -100,39 +81,36 @@ static void inject_undef32(struct kvm_vcpu *vcpu)
  * Modelled after TakeDataAbortException() and TakePrefetchAbortException
  * pseudocode.
  */
-static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt,
-                        unsigned long addr)
+static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt, u32 addr)
 {
-       u32 *far, *fsr;
-       bool is_lpae;
-       bool loaded;
+       u64 far;
+       u32 fsr;
+
+       /* Give the guest an IMPLEMENTATION DEFINED exception */
+       if (vcpu_read_sys_reg(vcpu, TCR_EL1) & TTBCR_EAE) {
+               fsr = DFSR_LPAE | DFSR_FSC_EXTABT_LPAE;
+       } else {
+               /* no need to shuffle FS[4] into DFSR[10] as its 0 */
+               fsr = DFSR_FSC_EXTABT_nLPAE;
+       }
 
-       loaded = pre_fault_synchronize(vcpu);
+       far = vcpu_read_sys_reg(vcpu, FAR_EL1);
 
        if (is_pabt) {
                vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA32_IABT |
                                     KVM_ARM64_PENDING_EXCEPTION);
-               far = &vcpu_cp15(vcpu, c6_IFAR);
-               fsr = &vcpu_cp15(vcpu, c5_IFSR);
+               far &= GENMASK(31, 0);
+               far |= (u64)addr << 32;
+               vcpu_write_sys_reg(vcpu, fsr, IFSR32_EL2);
        } else { /* !iabt */
                vcpu->arch.flags |= (KVM_ARM64_EXCEPT_AA32_DABT |
                                     KVM_ARM64_PENDING_EXCEPTION);
-               far = &vcpu_cp15(vcpu, c6_DFAR);
-               fsr = &vcpu_cp15(vcpu, c5_DFSR);
-       }
-
-       *far = addr;
-
-       /* Give the guest an IMPLEMENTATION DEFINED exception */
-       is_lpae = (vcpu_cp15(vcpu, c2_TTBCR) >> 31);
-       if (is_lpae) {
-               *fsr = DFSR_LPAE | DFSR_FSC_EXTABT_LPAE;
-       } else {
-               /* no need to shuffle FS[4] into DFSR[10] as its 0 */
-               *fsr = DFSR_FSC_EXTABT_nLPAE;
+               far &= GENMASK(63, 32);
+               far |= addr;
+               vcpu_write_sys_reg(vcpu, fsr, ESR_EL1);
        }
 
-       post_fault_synchronize(vcpu, loaded);
+       vcpu_write_sys_reg(vcpu, far, FAR_EL1);
 }
 
 /**