target/i386: introduce function to query MMU indices

Remove knowledge of specific MMU indexes (other than MMU_NESTED_IDX and
MMU_PHYS_IDX) from mmu_translate().  This will make it possible to split
32-bit and 64-bit MMU indexes.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target/i386/cpu.h

@@ -2305,6 +2305,16 @@ uint64_t cpu_get_tsc(CPUX86State *env);
 #define MMU_NESTED_IDX  3
 #define MMU_PHYS_IDX    4
 
+static inline bool is_mmu_index_smap(int mmu_index)
+{
+    return mmu_index == MMU_KSMAP_IDX;
+}
+
+static inline bool is_mmu_index_user(int mmu_index)
+{
+    return mmu_index == MMU_USER_IDX;
+}
+
 static inline int cpu_mmu_index_kernel(CPUX86State *env)
 {
     return !(env->hflags & HF_SMAP_MASK) ? MMU_KNOSMAP_IDX :

target/i386/tcg/sysemu/excp_helper.c

@@ -137,7 +137,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in,
     const int32_t a20_mask = x86_get_a20_mask(env);
     const target_ulong addr = in->addr;
     const int pg_mode = in->pg_mode;
-    const bool is_user = (in->mmu_idx == MMU_USER_IDX);
+    const bool is_user = is_mmu_index_user(in->mmu_idx);
     const MMUAccessType access_type = in->access_type;
     uint64_t ptep, pte, rsvd_mask;
     PTETranslate pte_trans = {
@@ -363,7 +363,7 @@ static bool mmu_translate(CPUX86State *env, const TranslateParams *in,
     }
 
     int prot = 0;
-    if (in->mmu_idx != MMU_KSMAP_IDX || !(ptep & PG_USER_MASK)) {
+    if (!is_mmu_index_smap(in->mmu_idx) || !(ptep & PG_USER_MASK)) {
         prot |= PAGE_READ;
         if ((ptep & PG_RW_MASK) || !(is_user || (pg_mode & PG_MODE_WP))) {
             prot |= PAGE_WRITE;