KVM: PPC: PV mtmsrd L=0 and mtmsr

[~andy/linux] / arch / powerpc / kernel / kvm.c

diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c
index 717ab0dded2521427a5821d7af366b62d6cb4f1c..8ac57e2c52faeeb84dc12f7a6f998648d77ef493 100644 (file)
--- a/arch/powerpc/kernel/kvm.c
+++ b/arch/powerpc/kernel/kvm.c
@@ -63,7 +63,9 @@
 #define KVM_INST_MTSPR_DSISR   0x7c1203a6
 
 #define KVM_INST_TLBSYNC       0x7c00046c
+#define KVM_INST_MTMSRD_L0     0x7c000164
 #define KVM_INST_MTMSRD_L1     0x7c010164
+#define KVM_INST_MTMSR         0x7c000124
 
 static bool kvm_patching_worked = true;
 static char kvm_tmp[1024 * 1024];
@@ -176,6 +178,49 @@ static void kvm_patch_ins_mtmsrd(u32 *inst, u32 rt)
        kvm_patch_ins_b(inst, distance_start);
 }
 
+extern u32 kvm_emulate_mtmsr_branch_offs;
+extern u32 kvm_emulate_mtmsr_reg1_offs;
+extern u32 kvm_emulate_mtmsr_reg2_offs;
+extern u32 kvm_emulate_mtmsr_reg3_offs;
+extern u32 kvm_emulate_mtmsr_orig_ins_offs;
+extern u32 kvm_emulate_mtmsr_len;
+extern u32 kvm_emulate_mtmsr[];
+
+static void kvm_patch_ins_mtmsr(u32 *inst, u32 rt)
+{
+       u32 *p;
+       int distance_start;
+       int distance_end;
+       ulong next_inst;
+
+       p = kvm_alloc(kvm_emulate_mtmsr_len * 4);
+       if (!p)
+               return;
+
+       /* Find out where we are and put everything there */
+       distance_start = (ulong)p - (ulong)inst;
+       next_inst = ((ulong)inst + 4);
+       distance_end = next_inst - (ulong)&p[kvm_emulate_mtmsr_branch_offs];
+
+       /* Make sure we only write valid b instructions */
+       if (distance_start > KVM_INST_B_MAX) {
+               kvm_patching_worked = false;
+               return;
+       }
+
+       /* Modify the chunk to fit the invocation */
+       memcpy(p, kvm_emulate_mtmsr, kvm_emulate_mtmsr_len * 4);
+       p[kvm_emulate_mtmsr_branch_offs] |= distance_end & KVM_INST_B_MASK;
+       p[kvm_emulate_mtmsr_reg1_offs] |= rt;
+       p[kvm_emulate_mtmsr_reg2_offs] |= rt;
+       p[kvm_emulate_mtmsr_reg3_offs] |= rt;
+       p[kvm_emulate_mtmsr_orig_ins_offs] = *inst;
+       flush_icache_range((ulong)p, (ulong)p + kvm_emulate_mtmsr_len * 4);
+
+       /* Patch the invocation */
+       kvm_patch_ins_b(inst, distance_start);
+}
+
 static void kvm_map_magic_page(void *data)
 {
        kvm_hypercall2(KVM_HC_PPC_MAP_MAGIC_PAGE,
@@ -256,6 +301,12 @@ static void kvm_check_ins(u32 *inst)
                if (get_rt(inst_rt) < 30)
                        kvm_patch_ins_mtmsrd(inst, inst_rt);
                break;
+       case KVM_INST_MTMSR:
+       case KVM_INST_MTMSRD_L0:
+               /* We use r30 and r31 during the hook */
+               if (get_rt(inst_rt) < 30)
+                       kvm_patch_ins_mtmsr(inst, inst_rt);
+               break;
        }
 
        switch (_inst) {