MIPS: KVM: Save k0 straight into VCPU structure

[linux-2.6-block.git] / arch / mips / kvm / entry.c

diff --git a/arch/mips/kvm/entry.c b/arch/mips/kvm/entry.c
index fb2cbf653474eb22733621b8d059c42adbaede40..de8b6ec5573f43331c9a1e15aac50139af00f8a7 100644 (file)
--- a/arch/mips/kvm/entry.c
+++ b/arch/mips/kvm/entry.c
@@ -347,17 +347,15 @@ void *kvm_mips_build_exception(void *addr, void *handler)
        memset(labels, 0, sizeof(labels));
        memset(relocs, 0, sizeof(relocs));
 
-       /* Save guest k0 */
-       uasm_i_mtc0(&p, K0, scratch_tmp[0], scratch_tmp[1]);
-       uasm_i_ehb(&p);
+       /* Save guest k1 into scratch register */
+       uasm_i_mtc0(&p, K1, scratch_tmp[0], scratch_tmp[1]);
 
-       /* Get EBASE */
-       uasm_i_mfc0(&p, K0, C0_EBASE);
-       /* Get rid of CPUNum */
-       uasm_i_srl(&p, K0, K0, 10);
-       uasm_i_sll(&p, K0, K0, 10);
-       /* Save k1 @ offset 0x3000 */
-       UASM_i_SW(&p, K1, 0x3000, K0);
+       /* Get the VCPU pointer from the VCPU scratch register */
+       uasm_i_mfc0(&p, K1, scratch_vcpu[0], scratch_vcpu[1]);
+       uasm_i_addiu(&p, K1, K1, offsetof(struct kvm_vcpu, arch));
+
+       /* Save guest k0 into VCPU structure */
+       UASM_i_SW(&p, K0, offsetof(struct kvm_vcpu_arch, gprs[K0]), K1);
 
        /* Branch to the common handler */
        uasm_il_b(&p, &r, label_exit_common);
@@ -395,12 +393,13 @@ void *kvm_mips_build_exit(void *addr)
        /*
         * Generic Guest exception handler. We end up here when the guest
         * does something that causes a trap to kernel mode.
+        *
+        * Both k0/k1 registers will have already been saved (k0 into the vcpu
+        * structure, and k1 into the scratch_tmp register).
+        *
+        * The k1 register will already contain the kvm_vcpu_arch pointer.
         */
 
-       /* Get the VCPU pointer from the scratch register */
-       uasm_i_mfc0(&p, K1, scratch_vcpu[0], scratch_vcpu[1]);
-       uasm_i_addiu(&p, K1, K1, offsetof(struct kvm_vcpu, arch));
-
        /* Start saving Guest context to VCPU */
        for (i = 0; i < 32; ++i) {
                /* Guest k0/k1 saved later */
@@ -416,15 +415,9 @@ void *kvm_mips_build_exit(void *addr)
        uasm_i_mflo(&p, T0);
        UASM_i_SW(&p, T0, offsetof(struct kvm_vcpu_arch, lo), K1);
 
-       /* Finally save guest k0/k1 to VCPU */
+       /* Finally save guest k1 to VCPU */
+       uasm_i_ehb(&p);
        uasm_i_mfc0(&p, T0, scratch_tmp[0], scratch_tmp[1]);
-       UASM_i_SW(&p, T0, offsetof(struct kvm_vcpu_arch, gprs[K0]), K1);
-
-       /* Get GUEST k1 and save it in VCPU */
-       uasm_i_addiu(&p, T1, ZERO, ~0x2ff);
-       uasm_i_mfc0(&p, T0, C0_EBASE);
-       uasm_i_and(&p, T0, T0, T1);
-       UASM_i_LW(&p, T0, 0x3000, T0);
        UASM_i_SW(&p, T0, offsetof(struct kvm_vcpu_arch, gprs[K1]), K1);
 
        /* Now that context has been saved, we can use other registers */