virtual read handle sparc mmu

The sparc mmu currently doesn't support probe mode which is used by
uc_mem_read_virtual. So for now return UC_ERR_ARG when the sparc mmu
is used.

Author: PhilippTakacs

tests/unit/test_sparc.c

@@ -3,4 +3,20 @@
 const uint64_t code_start = 0x1000;
 const uint64_t code_len = 0x4000;
 
-TEST_LIST = {{NULL, NULL}};
+static void test_virtual_read(void)
+{
+    uc_engine *uc;
+    uint8_t u8 = 8;
+
+    OK(uc_open(UC_ARCH_SPARC, UC_MODE_SPARC32|UC_MODE_BIG_ENDIAN, &uc));
+    OK(uc_mem_map(uc, code_start, code_len, UC_PROT_ALL));
+
+    uc_assert_err(UC_ERR_ARG, uc_mem_read_virtual(uc, code_start, UC_PROT_READ, &u8, sizeof(u8)));
+    OK(uc_ctl_tlb_mode(uc, UC_TLB_VIRTUAL));
+    OK(uc_mem_read_virtual(uc, code_start, UC_PROT_READ, &u8, sizeof(u8)));
+}
+
+TEST_LIST = {
+        {"test_virtual_read", test_virtual_read},
+        {NULL, NULL}
+};

uc.c

@@ -790,6 +790,12 @@ uc_err uc_mem_read_virtual(uc_engine *uc, uint64_t address, uc_prot prot,
         return UC_ERR_ARG;
     }
 
+    // The sparc mmu doesn't support probe mode
+    if (uc->arch == UC_ARCH_SPARC && uc->cpu->cc->tlb_fill == uc->cpu->cc->tlb_fill_cpu) {
+        restore_jit_state(uc);
+        return UC_ERR_ARG;
+    }
+
     if (!(UC_PROT_READ == prot || UC_PROT_WRITE == prot ||
           UC_PROT_EXEC == prot)) {
         restore_jit_state(uc);