[Qemu-devel] [PATCH 3/5] s390x: update R and C bits in storage key

[Alexander Graf <agraf@suse.de>]

When the s390x maps a page or writes happen to a page, the R and C
bits get updated. The easiest way to implement this in qemu is to
simply update them whenever we map a TLB translation and act according
to the permissions.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 target-s390x/cpu.h       |    4 ++++
 target-s390x/helper.c    |   12 ++++++++++++
 target-s390x/op_helper.c |    1 -
 3 files changed, 16 insertions(+), 1 deletions(-)

diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index d48a9b7..8ec61f8 100644
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -819,6 +819,10 @@ struct sysib_322 {
 #define _PAGE_RO        0x200            /* HW read-only bit  */
 #define _PAGE_INVALID   0x400            /* HW invalid bit    */
 
+#define SK_C                    (0x1 << 1)
+#define SK_R                    (0x1 << 2)
+#define SK_F                    (0x1 << 3)
+#define SK_ACC_MASK             (0xf << 4)
 
 
 /* EBCDIC handling */
diff --git a/target-s390x/helper.c b/target-s390x/helper.c
index 1ce7079..f38859d 100644
--- a/target-s390x/helper.c
+++ b/target-s390x/helper.c
@@ -348,6 +348,7 @@ int mmu_translate(CPUState *env, target_ulong vaddr, int rw, uint64_t asc,
                   target_ulong *raddr, int *flags)
 {
     int r = -1;
+    uint8_t *sk;
 
     *flags = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
     vaddr &= TARGET_PAGE_MASK;
@@ -390,6 +391,17 @@ out:
         *raddr = *raddr + env->psa;
     }
 
+    if (*raddr <= ram_size) {
+        sk = &env->storage_keys[*raddr / TARGET_PAGE_SIZE];
+        if (*flags & PAGE_READ) {
+            *sk |= SK_R;
+        }
+    
+        if (*flags & PAGE_WRITE) {
+            *sk |= SK_C;
+        }
+    }
+
     return r;
 }
 
diff --git a/target-s390x/op_helper.c b/target-s390x/op_helper.c
index 245fb2c..7583172 100644
--- a/target-s390x/op_helper.c
+++ b/target-s390x/op_helper.c
@@ -2760,7 +2760,6 @@ uint64_t HELPER(iske)(uint64_t r2)
         return 0;
     }
 
-    /* XXX maybe use qemu's internal keys? */
     return env->storage_keys[addr / TARGET_PAGE_SIZE];
 }
 
-- 
1.6.0.2