s390x/tcg: implement TEST PROTECTION

Linux uses TEST PROTECTION to sense for available memory locations.

Let's implement what we can for now (just as for the other instructions,
excluding AR mode and special protection mechanisms).

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20171218224616.21030-2-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

diff --git a/target/s390x/helper.h b/target/s390x/helper.h
index 2f17b62d3d4aa2f114411beb6e1cd39d2341adee..26c1b07b44c6589d330a9ade7ae6d4b5bb9d7d2d 100644 (file)
--- a/target/s390x/helper.h
+++ b/target/s390x/helper.h
@@ -137,7 +137,7 @@ DEF_HELPER_FLAGS_4(lctlg, TCG_CALL_NO_WG, void, env, i32, i64, i32)
 DEF_HELPER_FLAGS_4(stctl, TCG_CALL_NO_WG, void, env, i32, i64, i32)
 DEF_HELPER_FLAGS_4(stctg, TCG_CALL_NO_WG, void, env, i32, i64, i32)
 DEF_HELPER_FLAGS_2(testblock, TCG_CALL_NO_WG, i32, env, i64)
-DEF_HELPER_FLAGS_2(tprot, TCG_CALL_NO_RWG, i32, i64, i64)
+DEF_HELPER_FLAGS_3(tprot, TCG_CALL_NO_RWG, i32, env, i64, i64)
 DEF_HELPER_FLAGS_2(iske, TCG_CALL_NO_RWG_SE, i64, env, i64)
 DEF_HELPER_FLAGS_3(sske, TCG_CALL_NO_RWG, void, env, i64, i64)
 DEF_HELPER_FLAGS_2(rrbe, TCG_CALL_NO_RWG, i32, env, i64)

diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
index 2625d843b3cab59b8325660bb0624283ea3245fb..359e446c6fc3773d648f4f748cc062d7bee810ce 100644 (file)
--- a/target/s390x/mem_helper.c
+++ b/target/s390x/mem_helper.c
@@ -1717,9 +1717,46 @@ uint32_t HELPER(testblock)(CPUS390XState *env, uint64_t real_addr)
     return 0;
 }
 
-uint32_t HELPER(tprot)(uint64_t a1, uint64_t a2)
+uint32_t HELPER(tprot)(CPUS390XState *env, uint64_t a1, uint64_t a2)
 {
-    /* XXX implement */
+    S390CPU *cpu = s390_env_get_cpu(env);
+    CPUState *cs = CPU(cpu);
+
+    /*
+     * TODO: we currently don't handle all access protection types
+     * (including access-list and key-controlled) as well as AR mode.
+     */
+    if (!s390_cpu_virt_mem_check_write(cpu, a1, 0, 1)) {
+        /* Fetching permitted; storing permitted */
+        return 0;
+    }
+    switch (env->int_pgm_code) {
+    case PGM_PROTECTION:
+        /* Fetching permitted; storing not permitted */
+        cs->exception_index = 0;
+        return 1;
+    case PGM_ADDRESSING:
+        /* Fetching not permitted; storing not permitted */
+        cs->exception_index = 0;
+        return 2;
+    case PGM_ASCE_TYPE:
+    case PGM_REG_FIRST_TRANS:
+    case PGM_REG_SEC_TRANS:
+    case PGM_REG_THIRD_TRANS:
+    case PGM_SEGMENT_TRANS:
+    case PGM_PAGE_TRANS:
+    case PGM_ALET_SPEC:
+    case PGM_ALEN_SPEC:
+    case PGM_ALE_SEQ:
+    case PGM_ASTE_VALID:
+    case PGM_ASTE_SEQ:
+    case PGM_EXT_AUTH:
+        /* Translation not available */
+        cs->exception_index = 0;
+        return 3;
+    }
+    /* any other exception is forwarded to the guest */
+    s390_cpu_virt_mem_handle_exc(cpu, GETPC());
     return 0;
 }
 

diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index ac55886792d1f49cda3252d2c295778581d7cdc4..df0b41606d2dad7834cb266b8876ce5b4b139c6d 100644 (file)
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -4532,7 +4532,7 @@ static ExitStatus op_testblock(DisasContext *s, DisasOps *o)
 
 static ExitStatus op_tprot(DisasContext *s, DisasOps *o)
 {
-    gen_helper_tprot(cc_op, o->addr1, o->in2);
+    gen_helper_tprot(cc_op, cpu_env, o->addr1, o->in2);
     set_cc_static(s);
     return NO_EXIT;
 }