KVM: MIPS: Introduce and use cpu_guest_has_ldpte

Loongson-3 has lddir/ldpte instructions and their related CP0 registers
are the same as HTW. So we introduce a cpu_guest_has_ldpte flag and use
it to indicate whether we need to save/restore HTW related CP0 registers
(PWBase, PWSize, PWField and PWCtl).

Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-Id: <1590220602-3547-7-git-send-email-chenhc@lemote.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h
index caecbae..724dfdd 100644 (file)
--- a/arch/mips/include/asm/cpu-features.h
+++ b/arch/mips/include/asm/cpu-features.h
@@ -682,6 +682,9 @@
 #ifndef cpu_guest_has_htw
 #define cpu_guest_has_htw      (cpu_data[0].guest.options & MIPS_CPU_HTW)
 #endif
+#ifndef cpu_guest_has_ldpte
+#define cpu_guest_has_ldpte    (cpu_data[0].guest.options & MIPS_CPU_LDPTE)
+#endif
 #ifndef cpu_guest_has_mvh
 #define cpu_guest_has_mvh      (cpu_data[0].guest.options & MIPS_CPU_MVH)
 #endif

diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 6b93162..f0e7f2d 100644 (file)
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -2017,8 +2017,10 @@ static inline void decode_cpucfg(struct cpuinfo_mips *c)
        if (cfg2 & LOONGSON_CFG2_LEXT2)
                c->ases |= MIPS_ASE_LOONGSON_EXT2;
 
-       if (cfg2 & LOONGSON_CFG2_LSPW)
+       if (cfg2 & LOONGSON_CFG2_LSPW) {
                c->options |= MIPS_CPU_LDPTE;
+               c->guest.options |= MIPS_CPU_LDPTE;
+       }
 
        if (cfg3 & LOONGSON_CFG3_LCAMP)
                c->ases |= MIPS_ASE_LOONGSON_CAM;

diff --git a/arch/mips/kvm/vz.c b/arch/mips/kvm/vz.c
index cc7fdbb..6e1b380 100644 (file)
--- a/arch/mips/kvm/vz.c
+++ b/arch/mips/kvm/vz.c
@@ -1706,7 +1706,7 @@ static unsigned long kvm_vz_num_regs(struct kvm_vcpu *vcpu)
                ret += ARRAY_SIZE(kvm_vz_get_one_regs_contextconfig);
        if (cpu_guest_has_segments)
                ret += ARRAY_SIZE(kvm_vz_get_one_regs_segments);
-       if (cpu_guest_has_htw)
+       if (cpu_guest_has_htw || cpu_guest_has_ldpte)
                ret += ARRAY_SIZE(kvm_vz_get_one_regs_htw);
        if (cpu_guest_has_maar && !cpu_guest_has_dyn_maar)
                ret += 1 + ARRAY_SIZE(vcpu->arch.maar);
@@ -1755,7 +1755,7 @@ static int kvm_vz_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
                        return -EFAULT;
                indices += ARRAY_SIZE(kvm_vz_get_one_regs_segments);
        }
-       if (cpu_guest_has_htw) {
+       if (cpu_guest_has_htw || cpu_guest_has_ldpte) {
                if (copy_to_user(indices, kvm_vz_get_one_regs_htw,
                                 sizeof(kvm_vz_get_one_regs_htw)))
                        return -EFAULT;
@@ -1878,17 +1878,17 @@ static int kvm_vz_get_one_reg(struct kvm_vcpu *vcpu,
                *v = read_gc0_segctl2();
                break;
        case KVM_REG_MIPS_CP0_PWBASE:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                *v = read_gc0_pwbase();
                break;
        case KVM_REG_MIPS_CP0_PWFIELD:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                *v = read_gc0_pwfield();
                break;
        case KVM_REG_MIPS_CP0_PWSIZE:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                *v = read_gc0_pwsize();
                break;
@@ -1896,7 +1896,7 @@ static int kvm_vz_get_one_reg(struct kvm_vcpu *vcpu,
                *v = (long)read_gc0_wired();
                break;
        case KVM_REG_MIPS_CP0_PWCTL:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                *v = read_gc0_pwctl();
                break;
@@ -2101,17 +2101,17 @@ static int kvm_vz_set_one_reg(struct kvm_vcpu *vcpu,
                write_gc0_segctl2(v);
                break;
        case KVM_REG_MIPS_CP0_PWBASE:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                write_gc0_pwbase(v);
                break;
        case KVM_REG_MIPS_CP0_PWFIELD:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                write_gc0_pwfield(v);
                break;
        case KVM_REG_MIPS_CP0_PWSIZE:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                write_gc0_pwsize(v);
                break;
@@ -2119,7 +2119,7 @@ static int kvm_vz_set_one_reg(struct kvm_vcpu *vcpu,
                change_gc0_wired(MIPSR6_WIRED_WIRED, v);
                break;
        case KVM_REG_MIPS_CP0_PWCTL:
-               if (!cpu_guest_has_htw)
+               if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
                        return -EINVAL;
                write_gc0_pwctl(v);
                break;
@@ -2580,7 +2580,7 @@ static int kvm_vz_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
        }
 
        /* restore HTW registers */
-       if (cpu_guest_has_htw) {
+       if (cpu_guest_has_htw || cpu_guest_has_ldpte) {
                kvm_restore_gc0_pwbase(cop0);
                kvm_restore_gc0_pwfield(cop0);
                kvm_restore_gc0_pwsize(cop0);
@@ -2685,8 +2685,8 @@ static int kvm_vz_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
        }
 
        /* save HTW registers if enabled in guest */
-       if (cpu_guest_has_htw &&
-           kvm_read_sw_gc0_config3(cop0) & MIPS_CONF3_PW) {
+       if (cpu_guest_has_ldpte || (cpu_guest_has_htw &&
+           kvm_read_sw_gc0_config3(cop0) & MIPS_CONF3_PW)) {
                kvm_save_gc0_pwbase(cop0);
                kvm_save_gc0_pwfield(cop0);
                kvm_save_gc0_pwsize(cop0);