KVM: MIPS/VZ: Support guest CP0_BadInstr[P]

Add support for VZ guest CP0_BadInstr and CP0_BadInstrP registers, as
found on most VZ capable cores. These guest registers need context
switching, and exposing via the KVM ioctl API when they are present.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: linux-doc@vger.kernel.org

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index d282786..5ef4fa1 100644 (file)
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2079,6 +2079,8 @@ registers, find a list below:
   MIPS  | KVM_REG_MIPS_CP0_WIRED        | 32
   MIPS  | KVM_REG_MIPS_CP0_HWRENA       | 32
   MIPS  | KVM_REG_MIPS_CP0_BADVADDR     | 64
+  MIPS  | KVM_REG_MIPS_CP0_BADINSTR     | 32
+  MIPS  | KVM_REG_MIPS_CP0_BADINSTRP    | 32
   MIPS  | KVM_REG_MIPS_CP0_COUNT        | 32
   MIPS  | KVM_REG_MIPS_CP0_ENTRYHI      | 64
   MIPS  | KVM_REG_MIPS_CP0_COMPARE      | 32

diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index bc3f9de..3a9ca33 100644 (file)
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -40,6 +40,8 @@
 #define KVM_REG_MIPS_CP0_WIRED         MIPS_CP0_32(6, 0)
 #define KVM_REG_MIPS_CP0_HWRENA                MIPS_CP0_32(7, 0)
 #define KVM_REG_MIPS_CP0_BADVADDR      MIPS_CP0_64(8, 0)
+#define KVM_REG_MIPS_CP0_BADINSTR      MIPS_CP0_32(8, 1)
+#define KVM_REG_MIPS_CP0_BADINSTRP     MIPS_CP0_32(8, 2)
 #define KVM_REG_MIPS_CP0_COUNT         MIPS_CP0_32(9, 0)
 #define KVM_REG_MIPS_CP0_ENTRYHI       MIPS_CP0_64(10, 0)
 #define KVM_REG_MIPS_CP0_COMPARE       MIPS_CP0_32(11, 0)
@@ -669,6 +671,8 @@ __BUILD_KVM_RW_HW(pagegrain,      32, MIPS_CP0_TLB_PG_MASK,  1)
 __BUILD_KVM_RW_HW(wired,          32, MIPS_CP0_TLB_WIRED,    0)
 __BUILD_KVM_RW_HW(hwrena,         32, MIPS_CP0_HWRENA,       0)
 __BUILD_KVM_RW_HW(badvaddr,       l,  MIPS_CP0_BAD_VADDR,    0)
+__BUILD_KVM_RW_HW(badinstr,       32, MIPS_CP0_BAD_VADDR,    1)
+__BUILD_KVM_RW_HW(badinstrp,      32, MIPS_CP0_BAD_VADDR,    2)
 __BUILD_KVM_RW_SW(count,          32, MIPS_CP0_COUNT,        0)
 __BUILD_KVM_RW_HW(entryhi,        l,  MIPS_CP0_TLB_HI,       0)
 __BUILD_KVM_RW_HW(compare,        32, MIPS_CP0_COMPARE,      0)

diff --git a/arch/mips/kvm/vz.c b/arch/mips/kvm/vz.c
index cfed234..ec909fc 100644 (file)
--- a/arch/mips/kvm/vz.c
+++ b/arch/mips/kvm/vz.c
@@ -1221,6 +1221,10 @@ static unsigned long kvm_vz_num_regs(struct kvm_vcpu *vcpu)
        ret = ARRAY_SIZE(kvm_vz_get_one_regs);
        if (cpu_guest_has_userlocal)
                ++ret;
+       if (cpu_guest_has_badinstr)
+               ++ret;
+       if (cpu_guest_has_badinstrp)
+               ++ret;
        ret += __arch_hweight8(cpu_data[0].guest.kscratch_mask);
 
        return ret;
@@ -1242,6 +1246,18 @@ static int kvm_vz_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
                        return -EFAULT;
                ++indices;
        }
+       if (cpu_guest_has_badinstr) {
+               index = KVM_REG_MIPS_CP0_BADINSTR;
+               if (copy_to_user(indices, &index, sizeof(index)))
+                       return -EFAULT;
+               ++indices;
+       }
+       if (cpu_guest_has_badinstrp) {
+               index = KVM_REG_MIPS_CP0_BADINSTRP;
+               if (copy_to_user(indices, &index, sizeof(index)))
+                       return -EFAULT;
+               ++indices;
+       }
        for (i = 0; i < 6; ++i) {
                if (!cpu_guest_has_kscr(i + 2))
                        continue;
@@ -1327,6 +1343,16 @@ static int kvm_vz_get_one_reg(struct kvm_vcpu *vcpu,
        case KVM_REG_MIPS_CP0_BADVADDR:
                *v = (long)read_gc0_badvaddr();
                break;
+       case KVM_REG_MIPS_CP0_BADINSTR:
+               if (!cpu_guest_has_badinstr)
+                       return -EINVAL;
+               *v = read_gc0_badinstr();
+               break;
+       case KVM_REG_MIPS_CP0_BADINSTRP:
+               if (!cpu_guest_has_badinstrp)
+                       return -EINVAL;
+               *v = read_gc0_badinstrp();
+               break;
        case KVM_REG_MIPS_CP0_COUNT:
                *v = kvm_mips_read_count(vcpu);
                break;
@@ -1472,6 +1498,16 @@ static int kvm_vz_set_one_reg(struct kvm_vcpu *vcpu,
        case KVM_REG_MIPS_CP0_BADVADDR:
                write_gc0_badvaddr(v);
                break;
+       case KVM_REG_MIPS_CP0_BADINSTR:
+               if (!cpu_guest_has_badinstr)
+                       return -EINVAL;
+               write_gc0_badinstr(v);
+               break;
+       case KVM_REG_MIPS_CP0_BADINSTRP:
+               if (!cpu_guest_has_badinstrp)
+                       return -EINVAL;
+               write_gc0_badinstrp(v);
+               break;
        case KVM_REG_MIPS_CP0_COUNT:
                kvm_mips_write_count(vcpu, v);
                break;
@@ -1871,6 +1907,11 @@ static int kvm_vz_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
                        kvm_restore_gc0_kscratch6(cop0);
        }
 
+       if (cpu_guest_has_badinstr)
+               kvm_restore_gc0_badinstr(cop0);
+       if (cpu_guest_has_badinstrp)
+               kvm_restore_gc0_badinstrp(cop0);
+
        /* restore Root.GuestCtl2 from unused Guest guestctl2 register */
        if (cpu_has_guestctl2)
                write_c0_guestctl2(
@@ -1945,6 +1986,11 @@ static int kvm_vz_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
                        kvm_save_gc0_kscratch6(cop0);
        }
 
+       if (cpu_guest_has_badinstr)
+               kvm_save_gc0_badinstr(cop0);
+       if (cpu_guest_has_badinstrp)
+               kvm_save_gc0_badinstrp(cop0);
+
        kvm_vz_save_timer(vcpu);
 
        /* save Root.GuestCtl2 in unused Guest guestctl2 register */