MIPS: KVM: Implement PRid CP0 register access

Implement access to the guest Processor Identification CP0 register
using the KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctls. This allows the
owning process to modify and read back the value that is exposed to the
guest in this register.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 0d7fc66..9a5f8a4 100644 (file)
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1967,6 +1967,7 @@ registers, find a list below:
   MIPS  | KVM_REG_MIPS_CP0_STATUS       | 32
   MIPS  | KVM_REG_MIPS_CP0_CAUSE        | 32
   MIPS  | KVM_REG_MIPS_CP0_EPC          | 64
+  MIPS  | KVM_REG_MIPS_CP0_PRID         | 32
   MIPS  | KVM_REG_MIPS_CP0_CONFIG       | 32
   MIPS  | KVM_REG_MIPS_CP0_CONFIG1      | 32
   MIPS  | KVM_REG_MIPS_CP0_CONFIG2      | 32

diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 8fc3ba2..26d91b0 100644 (file)
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -42,6 +42,7 @@
 #define KVM_REG_MIPS_CP0_STATUS                MIPS_CP0_32(12, 0)
 #define KVM_REG_MIPS_CP0_CAUSE         MIPS_CP0_32(13, 0)
 #define KVM_REG_MIPS_CP0_EPC           MIPS_CP0_64(14, 0)
+#define KVM_REG_MIPS_CP0_PRID          MIPS_CP0_32(15, 0)
 #define KVM_REG_MIPS_CP0_EBASE         MIPS_CP0_64(15, 1)
 #define KVM_REG_MIPS_CP0_CONFIG                MIPS_CP0_32(16, 0)
 #define KVM_REG_MIPS_CP0_CONFIG1       MIPS_CP0_32(16, 1)

diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 399b551..fd620cc 100644 (file)
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -505,6 +505,7 @@ static u64 kvm_mips_get_one_regs[] = {
        KVM_REG_MIPS_CP0_STATUS,
        KVM_REG_MIPS_CP0_CAUSE,
        KVM_REG_MIPS_CP0_EPC,
+       KVM_REG_MIPS_CP0_PRID,
        KVM_REG_MIPS_CP0_CONFIG,
        KVM_REG_MIPS_CP0_CONFIG1,
        KVM_REG_MIPS_CP0_CONFIG2,
@@ -574,6 +575,9 @@ static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
        case KVM_REG_MIPS_CP0_EPC:
                v = (long)kvm_read_c0_guest_epc(cop0);
                break;
+       case KVM_REG_MIPS_CP0_PRID:
+               v = (long)kvm_read_c0_guest_prid(cop0);
+               break;
        case KVM_REG_MIPS_CP0_ERROREPC:
                v = (long)kvm_read_c0_guest_errorepc(cop0);
                break;
@@ -687,6 +691,9 @@ static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
        case KVM_REG_MIPS_CP0_EPC:
                kvm_write_c0_guest_epc(cop0, v);
                break;
+       case KVM_REG_MIPS_CP0_PRID:
+               kvm_write_c0_guest_prid(cop0, v);
+               break;
        case KVM_REG_MIPS_CP0_ERROREPC:
                kvm_write_c0_guest_errorepc(cop0, v);
                break;