[PATCH v1 04/12] s390x/tcg: check for addressing exceptions for for RRBE, SSKE and ISKE

[David Hildenbrand <david@redhat.com>]

Let's replace the ram_size check by a proper physical address space
check (for example, to prepare for memory hotplug), trigger addressing
exceptions and trace the return value of the storage key getter/setter.

Provide an helper mmu_absolute_addr_valid() to be used in other context
soon. Always test for "read" instead of "write" as we are not actually
modifying the page itself.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 target/s390x/helper.h         |  6 +++---
 target/s390x/mmu_helper.c     |  8 ++++++++
 target/s390x/s390x-internal.h |  1 +
 target/s390x/tcg/mem_helper.c | 37 +++++++++++++++++++++++------------
 4 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/target/s390x/helper.h b/target/s390x/helper.h
index 6215ca00bc..271b081e8c 100644
--- a/target/s390x/helper.h
+++ b/target/s390x/helper.h
@@ -336,9 +336,9 @@ 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_3(tprot, TCG_CALL_NO_WG, 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)
+DEF_HELPER_2(iske, i64, env, i64)
+DEF_HELPER_3(sske, void, env, i64, i64)
+DEF_HELPER_2(rrbe, i32, env, i64)
 DEF_HELPER_4(mvcs, i32, env, i64, i64, i64)
 DEF_HELPER_4(mvcp, i32, env, i64, i64, i64)
 DEF_HELPER_4(sigp, i32, env, i64, i32, i32)
diff --git a/target/s390x/mmu_helper.c b/target/s390x/mmu_helper.c
index d779a9fc51..0620b1803e 100644
--- a/target/s390x/mmu_helper.c
+++ b/target/s390x/mmu_helper.c
@@ -94,6 +94,14 @@ target_ulong mmu_real2abs(CPUS390XState *env, target_ulong raddr)
     return raddr;
 }
 
+bool mmu_absolute_addr_valid(target_ulong addr, bool is_write)
+{
+    return address_space_access_valid(&address_space_memory,
+                                      addr & TARGET_PAGE_MASK,
+                                      TARGET_PAGE_SIZE, is_write,
+                                      MEMTXATTRS_UNSPECIFIED);
+}
+
 static inline bool read_table_entry(CPUS390XState *env, hwaddr gaddr,
                                     uint64_t *entry)
 {
diff --git a/target/s390x/s390x-internal.h b/target/s390x/s390x-internal.h
index 5506f185e8..d246d26b04 100644
--- a/target/s390x/s390x-internal.h
+++ b/target/s390x/s390x-internal.h
@@ -373,6 +373,7 @@ void probe_write_access(CPUS390XState *env, uint64_t addr, uint64_t len,
 
 
 /* mmu_helper.c */
+bool mmu_absolute_addr_valid(target_ulong addr, bool is_write);
 int mmu_translate(CPUS390XState *env, target_ulong vaddr, int rw, uint64_t asc,
                   target_ulong *raddr, int *flags, uint64_t *tec);
 int mmu_translate_real(CPUS390XState *env, target_ulong raddr, int rw,
diff --git a/target/s390x/tcg/mem_helper.c b/target/s390x/tcg/mem_helper.c
index dd506d8d17..a84795cfa3 100644
--- a/target/s390x/tcg/mem_helper.c
+++ b/target/s390x/tcg/mem_helper.c
@@ -28,6 +28,7 @@
 #include "qemu/int128.h"
 #include "qemu/atomic128.h"
 #include "tcg/tcg.h"
+#include "trace.h"
 
 #if !defined(CONFIG_USER_ONLY)
 #include "hw/s390x/storage-keys.h"
@@ -2171,15 +2172,15 @@ uint32_t HELPER(tprot)(CPUS390XState *env, uint64_t a1, uint64_t a2)
 /* insert storage key extended */
 uint64_t HELPER(iske)(CPUS390XState *env, uint64_t r2)
 {
-    MachineState *ms = MACHINE(qdev_get_machine());
     static S390SKeysState *ss;
     static S390SKeysClass *skeyclass;
     uint64_t addr = wrap_address(env, r2);
     uint8_t key;
+    int rc;
 
     addr = mmu_real2abs(env, addr);
-    if (addr > ms->ram_size) {
-        return 0;
+    if (!mmu_absolute_addr_valid(addr, false)) {
+        trigger_pgm_exception(env, PGM_ADDRESSING);
     }
 
     if (unlikely(!ss)) {
@@ -2187,7 +2188,9 @@ uint64_t HELPER(iske)(CPUS390XState *env, uint64_t r2)
         skeyclass = S390_SKEYS_GET_CLASS(ss);
     }
 
-    if (skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key)) {
+    rc = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
+    if (rc) {
+        trace_get_skeys_nonzero(rc);
         return 0;
     }
     return key;
@@ -2196,15 +2199,15 @@ uint64_t HELPER(iske)(CPUS390XState *env, uint64_t r2)
 /* set storage key extended */
 void HELPER(sske)(CPUS390XState *env, uint64_t r1, uint64_t r2)
 {
-    MachineState *ms = MACHINE(qdev_get_machine());
     static S390SKeysState *ss;
     static S390SKeysClass *skeyclass;
     uint64_t addr = wrap_address(env, r2);
     uint8_t key;
+    int rc;
 
     addr = mmu_real2abs(env, addr);
-    if (addr > ms->ram_size) {
-        return;
+    if (!mmu_absolute_addr_valid(addr, false)) {
+        trigger_pgm_exception(env, PGM_ADDRESSING);
     }
 
     if (unlikely(!ss)) {
@@ -2213,7 +2216,11 @@ void HELPER(sske)(CPUS390XState *env, uint64_t r1, uint64_t r2)
     }
 
     key = r1 & 0xfe;
-    skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
+    rc = skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
+    if (rc) {
+        trace_set_skeys_nonzero(rc);
+        return 0;
+    }
    /*
     * As we can only flush by virtual address and not all the entries
     * that point to a physical address we have to flush the whole TLB.
@@ -2224,15 +2231,15 @@ void HELPER(sske)(CPUS390XState *env, uint64_t r1, uint64_t r2)
 /* reset reference bit extended */
 uint32_t HELPER(rrbe)(CPUS390XState *env, uint64_t r2)
 {
-    MachineState *ms = MACHINE(qdev_get_machine());
     uint64_t addr = wrap_address(env, r2);
     static S390SKeysState *ss;
     static S390SKeysClass *skeyclass;
     uint8_t re, key;
+    int rc;
 
     addr = mmu_real2abs(env, addr);
-    if (addr > ms->ram_size) {
-        return 0;
+    if (!mmu_absolute_addr_valid(addr, false)) {
+        trigger_pgm_exception(env, PGM_ADDRESSING);
     }
 
     if (unlikely(!ss)) {
@@ -2240,14 +2247,18 @@ uint32_t HELPER(rrbe)(CPUS390XState *env, uint64_t r2)
         skeyclass = S390_SKEYS_GET_CLASS(ss);
     }
 
-    if (skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key)) {
+    rc = skeyclass->get_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
+    if (rc) {
+        trace_get_skeys_nonzero(rc);
         return 0;
     }
 
     re = key & (SK_R | SK_C);
     key &= ~SK_R;
 
-    if (skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key)) {
+    rc = skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key);
+    if (rc) {
+        trace_set_skeys_nonzero(rc);
         return 0;
     }
    /*
-- 
2.31.1