KVM: PPC: Add mtsrin PV code

[firefly-linux-kernel-4.4.55.git] / arch / powerpc / kernel / kvm.c

diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c
index 226882fe85a6581876a06721147dcaa90619eb73..c8bab24ff8ac4bc922453743aacb75dd1bbe82bf 100644 (file)
--- a/arch/powerpc/kernel/kvm.c
+++ b/arch/powerpc/kernel/kvm.c
@@ -42,6 +42,7 @@
 #define KVM_INST_B_MAX         0x01ffffff
 
 #define KVM_MASK_RT            0x03e00000
+#define KVM_MASK_RB            0x0000f800
 #define KVM_INST_MFMSR         0x7c0000a6
 #define KVM_INST_MFSPR_SPRG0   0x7c1042a6
 #define KVM_INST_MFSPR_SPRG1   0x7c1142a6
@@ -69,6 +70,8 @@
 #define KVM_INST_WRTEEI_0      0x7c000146
 #define KVM_INST_WRTEEI_1      0x7c008146
 
+#define KVM_INST_MTSRIN                0x7c0001e4
+
 static bool kvm_patching_worked = true;
 static char kvm_tmp[1024 * 1024];
 static int kvm_tmp_index;
@@ -264,6 +267,51 @@ static void kvm_patch_ins_wrteei(u32 *inst)
 
 #endif
 
+#ifdef CONFIG_PPC_BOOK3S_32
+
+extern u32 kvm_emulate_mtsrin_branch_offs;
+extern u32 kvm_emulate_mtsrin_reg1_offs;
+extern u32 kvm_emulate_mtsrin_reg2_offs;
+extern u32 kvm_emulate_mtsrin_orig_ins_offs;
+extern u32 kvm_emulate_mtsrin_len;
+extern u32 kvm_emulate_mtsrin[];
+
+static void kvm_patch_ins_mtsrin(u32 *inst, u32 rt, u32 rb)
+{
+       u32 *p;
+       int distance_start;
+       int distance_end;
+       ulong next_inst;
+
+       p = kvm_alloc(kvm_emulate_mtsrin_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_mtsrin_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_mtsrin, kvm_emulate_mtsrin_len * 4);
+       p[kvm_emulate_mtsrin_branch_offs] |= distance_end & KVM_INST_B_MASK;
+       p[kvm_emulate_mtsrin_reg1_offs] |= (rb << 10);
+       p[kvm_emulate_mtsrin_reg2_offs] |= rt;
+       p[kvm_emulate_mtsrin_orig_ins_offs] = *inst;
+       flush_icache_range((ulong)p, (ulong)p + kvm_emulate_mtsrin_len * 4);
+
+       /* Patch the invocation */
+       kvm_patch_ins_b(inst, distance_start);
+}
+
+#endif
+
 static void kvm_map_magic_page(void *data)
 {
        u32 *features = data;
@@ -360,6 +408,18 @@ static void kvm_check_ins(u32 *inst, u32 features)
                break;
        }
 
+       switch (inst_no_rt & ~KVM_MASK_RB) {
+#ifdef CONFIG_PPC_BOOK3S_32
+       case KVM_INST_MTSRIN:
+               if (features & KVM_MAGIC_FEAT_SR) {
+                       u32 inst_rb = _inst & KVM_MASK_RB;
+                       kvm_patch_ins_mtsrin(inst, inst_rt, inst_rb);
+               }
+               break;
+               break;
+#endif
+       }
+
        switch (_inst) {
 #ifdef CONFIG_BOOKE
        case KVM_INST_WRTEEI_0: