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, 30 insertions, 16 deletions

diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index 1c0e78c64b..8e65e43f02 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -555,6 +555,7 @@ int kvm_s390_set_clock(uint8_t *tod_high, uint64_t *tod_low)
 /**
  * kvm_s390_mem_op:
  * @addr:      the logical start address in guest memory
+ * @ar:        the access register number
  * @hostbuf:   buffer in host memory. NULL = do only checks w/o copying
  * @len:       length that should be transfered
  * @is_write:  true = write, false = read
@@ -563,8 +564,8 @@ int kvm_s390_set_clock(uint8_t *tod_high, uint64_t *tod_low)
  * Use KVM ioctl to read/write from/to guest memory. An access exception
  * is injected into the vCPU in case of translation errors.
  */
-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)
 {
     struct kvm_s390_mem_op mem_op = {
         .gaddr = addr,
@@ -573,6 +574,7 @@ int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, void *hostbuf, int len,
         .op = is_write ? KVM_S390_MEMOP_LOGICAL_WRITE
                        : KVM_S390_MEMOP_LOGICAL_READ,
         .buf = (uint64_t)hostbuf,
+        .ar = ar,
     };
     int ret;
 
@@ -1017,7 +1019,8 @@ static int handle_b2(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
     return rc;
 }
 
-static uint64_t get_base_disp_rxy(S390CPU *cpu, struct kvm_run *run)
+static uint64_t get_base_disp_rxy(S390CPU *cpu, struct kvm_run *run,
+                                  uint8_t *ar)
 {
     CPUS390XState *env = &cpu->env;
     uint32_t x2 = (run->s390_sieic.ipa & 0x000f);
@@ -1028,12 +1031,16 @@ static uint64_t get_base_disp_rxy(S390CPU *cpu, struct kvm_run *run)
     if (disp2 & 0x80000) {
         disp2 += 0xfff00000;
     }
+    if (ar) {
+        *ar = base2;
+    }
 
     return (base2 ? env->regs[base2] : 0) +
            (x2 ? env->regs[x2] : 0) + (long)(int)disp2;
 }
 
-static uint64_t get_base_disp_rsy(S390CPU *cpu, struct kvm_run *run)
+static uint64_t get_base_disp_rsy(S390CPU *cpu, struct kvm_run *run,
+                                  uint8_t *ar)
 {
     CPUS390XState *env = &cpu->env;
     uint32_t base2 = run->s390_sieic.ipb >> 28;
@@ -1043,6 +1050,9 @@ static uint64_t get_base_disp_rsy(S390CPU *cpu, struct kvm_run *run)
     if (disp2 & 0x80000) {
         disp2 += 0xfff00000;
     }
+    if (ar) {
+        *ar = base2;
+    }
 
     return (base2 ? env->regs[base2] : 0) + (long)(int)disp2;
 }
@@ -1074,11 +1084,12 @@ static int kvm_stpcifc_service_call(S390CPU *cpu, struct kvm_run *run)
 {
     uint8_t r1 = (run->s390_sieic.ipa & 0x00f0) >> 4;
     uint64_t fiba;
+    uint8_t ar;
 
     cpu_synchronize_state(CPU(cpu));
-    fiba = get_base_disp_rxy(cpu, run);
+    fiba = get_base_disp_rxy(cpu, run, &ar);
 
-    return stpcifc_service_call(cpu, r1, fiba);
+    return stpcifc_service_call(cpu, r1, fiba, ar);
 }
 
 static int kvm_sic_service_call(S390CPU *cpu, struct kvm_run *run)
@@ -1100,22 +1111,24 @@ static int kvm_pcistb_service_call(S390CPU *cpu, struct kvm_run *run)
     uint8_t r1 = (run->s390_sieic.ipa & 0x00f0) >> 4;
     uint8_t r3 = run->s390_sieic.ipa & 0x000f;
     uint64_t gaddr;
+    uint8_t ar;
 
     cpu_synchronize_state(CPU(cpu));
-    gaddr = get_base_disp_rsy(cpu, run);
+    gaddr = get_base_disp_rsy(cpu, run, &ar);
 
-    return pcistb_service_call(cpu, r1, r3, gaddr);
+    return pcistb_service_call(cpu, r1, r3, gaddr, ar);
 }
 
 static int kvm_mpcifc_service_call(S390CPU *cpu, struct kvm_run *run)
 {
     uint8_t r1 = (run->s390_sieic.ipa & 0x00f0) >> 4;
     uint64_t fiba;
+    uint8_t ar;
 
     cpu_synchronize_state(CPU(cpu));
-    fiba = get_base_disp_rxy(cpu, run);
+    fiba = get_base_disp_rxy(cpu, run, &ar);
 
-    return mpcifc_service_call(cpu, r1, fiba);
+    return mpcifc_service_call(cpu, r1, fiba, ar);
 }
 
 static int handle_b9(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
@@ -1244,7 +1257,7 @@ static int handle_diag(S390CPU *cpu, struct kvm_run *run, uint32_t ipb)
      * For any diagnose call we support, bits 48-63 of the resulting
      * address specify the function code; the remainder is ignored.
      */
-    func_code = decode_basedisp_rs(&cpu->env, ipb) & DIAG_KVM_CODE_MASK;
+    func_code = decode_basedisp_rs(&cpu->env, ipb, NULL) & DIAG_KVM_CODE_MASK;
     switch (func_code) {
     case DIAG_IPL:
         kvm_handle_diag_308(cpu, run);
@@ -1591,7 +1604,8 @@ static int handle_sigp(S390CPU *cpu, struct kvm_run *run, uint8_t ipa1)
     cpu_synchronize_state(CPU(cpu));
 
     /* get order code */
-    order = decode_basedisp_rs(env, run->s390_sieic.ipb) & SIGP_ORDER_MASK;
+    order = decode_basedisp_rs(env, run->s390_sieic.ipb, NULL)
+        & SIGP_ORDER_MASK;
     status_reg = &env->regs[r1];
     param = (r1 % 2) ? env->regs[r1] : env->regs[r1 + 1];
 
@@ -1765,12 +1779,12 @@ static int handle_tsch(S390CPU *cpu)
     return ret;
 }
 
-static void insert_stsi_3_2_2(S390CPU *cpu, __u64 addr)
+static void insert_stsi_3_2_2(S390CPU *cpu, __u64 addr, uint8_t ar)
 {
     struct sysib_322 sysib;
     int del;
 
-    if (s390_cpu_virt_mem_read(cpu, addr, &sysib, sizeof(sysib))) {
+    if (s390_cpu_virt_mem_read(cpu, addr, ar, &sysib, sizeof(sysib))) {
         return;
     }
     /* Shift the stack of Extended Names to prepare for our own data */
@@ -1810,7 +1824,7 @@ static void insert_stsi_3_2_2(S390CPU *cpu, __u64 addr)
     /* Insert UUID */
     memcpy(sysib.vm[0].uuid, qemu_uuid, sizeof(sysib.vm[0].uuid));
 
-    s390_cpu_virt_mem_write(cpu, addr, &sysib, sizeof(sysib));
+    s390_cpu_virt_mem_write(cpu, addr, ar, &sysib, sizeof(sysib));
 }
 
 static int handle_stsi(S390CPU *cpu)
@@ -1824,7 +1838,7 @@ static int handle_stsi(S390CPU *cpu)
             return 0;
         }
         /* Only sysib 3.2.2 needs post-handling for now. */
-        insert_stsi_3_2_2(cpu, run->s390_stsi.addr);
+        insert_stsi_3_2_2(cpu, run->s390_stsi.addr, run->s390_stsi.ar);
         return 0;
     default:
         return 0;