s390x/kvm: Support access register mode for KVM_S390_MEM_OP ioctl

Access register mode is one of the modes that control dynamic address
translation. In this mode the address space is specified by values of
the access registers. The effective address-space-control element is
obtained from the result of the access register translation. See
the "Access-Register Introduction" section of the chapter 5 "Program
Execution" in "Principles of Operations" for more details.

When the CPU is in AR mode, the s390_cpu_virt_mem_rw() function must
know which access register number to use for address translation.
This patch does several things:
- add new parameter 'uint8_t ar' to that function
- decode ar number from intercepted instructions
- pass the ar number to s390_cpu_virt_mem_rw(), which in turn passes it
to the KVM_S390_MEM_OP ioctl.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 17 insertions, 13 deletions

diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h
index 9c4274325a..ba7d250962 100644
--- a/target-s390x/cpu.h
+++ b/target-s390x/cpu.h
@@ -356,7 +356,8 @@ int s390_cpu_handle_mmu_fault(CPUState *cpu, vaddr address, int rw,
 #ifndef CONFIG_USER_ONLY
 void do_restart_interrupt(CPUS390XState *env);
 
-static inline hwaddr decode_basedisp_s(CPUS390XState *env, uint32_t ipb)
+static inline hwaddr decode_basedisp_s(CPUS390XState *env, uint32_t ipb,
+                                       uint8_t *ar)
 {
     hwaddr addr = 0;
     uint8_t reg;
@@ -366,6 +367,9 @@ static inline hwaddr decode_basedisp_s(CPUS390XState *env, uint32_t ipb)
         addr = env->regs[reg];
     }
     addr += (ipb >> 16) & 0xfff;
+    if (ar) {
+        *ar = reg;
+    }
 
     return addr;
 }
@@ -401,8 +405,8 @@ void kvm_s390_vcpu_interrupt(S390CPU *cpu, struct kvm_s390_irq *irq);
 void kvm_s390_floating_interrupt(struct kvm_s390_irq *irq);
 int kvm_s390_inject_flic(struct kvm_s390_irq *irq);
 void kvm_s390_access_exception(S390CPU *cpu, uint16_t code, uint64_t te_code);
-int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, void *hostbuf, int len,
-                    bool is_write);
+int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf,
+                    int len, bool is_write);
 int kvm_s390_get_clock(uint8_t *tod_high, uint64_t *tod_clock);
 int kvm_s390_set_clock(uint8_t *tod_high, uint64_t *tod_clock);
 #else
@@ -420,8 +424,8 @@ static inline int kvm_s390_set_clock(uint8_t *tod_high, uint64_t *tod_low)
 {
     return -ENOSYS;
 }
-static inline int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, void *hostbuf,
-                                  int len, bool is_write)
+static inline int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar,
+                                  void *hostbuf, int len, bool is_write)
 {
     return -ENOSYS;
 }
@@ -963,15 +967,15 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
 uint32_t calc_cc(CPUS390XState *env, uint32_t cc_op, uint64_t src, uint64_t dst,
                  uint64_t vr);
 
-int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, void *hostbuf, int len,
-                         bool is_write);
+int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
+                         int len, bool is_write);
 
-#define s390_cpu_virt_mem_read(cpu, laddr, dest, len) \
-        s390_cpu_virt_mem_rw(cpu, laddr, dest, len, false)
-#define s390_cpu_virt_mem_write(cpu, laddr, dest, len) \
-        s390_cpu_virt_mem_rw(cpu, laddr, dest, len, true)
-#define s390_cpu_virt_mem_check_write(cpu, laddr, len) \
-        s390_cpu_virt_mem_rw(cpu, laddr, NULL, len, true)
+#define s390_cpu_virt_mem_read(cpu, laddr, ar, dest, len)    \
+        s390_cpu_virt_mem_rw(cpu, laddr, ar, dest, len, false)
+#define s390_cpu_virt_mem_write(cpu, laddr, ar, dest, len)       \
+        s390_cpu_virt_mem_rw(cpu, laddr, ar, dest, len, true)
+#define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len)   \
+        s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
 
 /* The value of the TOD clock for 1.1.1970. */
 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL