TEST BLOCK was likely once used to execute basic memory
tests, but nowadays it's just a (slow) way to clear a page.
Signed-off-by: Thomas Huth <th...@redhat.com>
---
v4:
- Switched TCG_CALL_NO_RWG back to TCG_CALL_NO_WG as indicated by Richard
v3:
- Use TCG_CALL_NO_RWG instead of TCG_CALL_NO_WG
- Use potential_page_fault() since the helper can generate an exception
v2:
- Use DEF_HELPER_FLAGS_2 instead for DEF_HELPER_2 for returning CC value
- Convert real to absolute address
- Added a check for valid RAM page
- Added low-address protection check
target/s390x/cpu.h | 1 +
target/s390x/helper.h | 1 +
target/s390x/insn-data.def | 2 ++
target/s390x/mem_helper.c | 28 ++++++++++++++++++++++++++++
target/s390x/mmu_helper.c | 2 +-
target/s390x/translate.c | 11 +++++++++++
6 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 240b8a5..4f38ba0 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -1082,6 +1082,7 @@ struct sysib_322 {
#define SIGP_ORDER_MASK 0x000000ff
void load_psw(CPUS390XState *env, uint64_t mask, uint64_t addr);
+target_ulong mmu_real2abs(CPUS390XState *env, target_ulong raddr);
int mmu_translate(CPUS390XState *env, target_ulong vaddr, int rw, uint64_t asc,
target_ulong *raddr, int *flags, bool exc);
int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
diff --git a/target/s390x/helper.h b/target/s390x/helper.h
index 0b70770..1fae191 100644
--- a/target/s390x/helper.h
+++ b/target/s390x/helper.h
@@ -102,6 +102,7 @@ DEF_HELPER_FLAGS_4(lctl, TCG_CALL_NO_WG, void, env, i32,
i64, i32)
DEF_HELPER_FLAGS_4(lctlg, TCG_CALL_NO_WG, void, env, i32, i64, i32)
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_2(tprot, TCG_CALL_NO_RWG, i32, 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)
diff --git a/target/s390x/insn-data.def b/target/s390x/insn-data.def
index 55a7c52..cac0f51 100644
--- a/target/s390x/insn-data.def
+++ b/target/s390x/insn-data.def
@@ -918,6 +918,8 @@
/* STORE USING REAL ADDRESS */
C(0xb246, STURA, RRE, Z, r1_o, r2_o, 0, 0, stura, 0)
C(0xb925, STURG, RRE, Z, r1_o, r2_o, 0, 0, sturg, 0)
+/* TEST BLOCK */
+ C(0xb22c, TB, RRE, Z, 0, r2_o, 0, 0, testblock, 0)
/* TEST PROTECTION */
C(0xe501, TPROT, SSE, Z, la1, a2, 0, 0, tprot, 0)
diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
index f6e5bce..0c6a0d9 100644
--- a/target/s390x/mem_helper.c
+++ b/target/s390x/mem_helper.c
@@ -20,6 +20,7 @@
#include "qemu/osdep.h"
#include "cpu.h"
+#include "exec/address-spaces.h"
#include "exec/helper-proto.h"
#include "exec/exec-all.h"
#include "exec/cpu_ldst.h"
@@ -973,6 +974,33 @@ void HELPER(stctl)(CPUS390XState *env, uint32_t r1,
uint64_t a2, uint32_t r3)
}
}
+uint32_t HELPER(testblock)(CPUS390XState *env, uint64_t real_addr)
+{
+ CPUState *cs = CPU(s390_env_get_cpu(env));
+ uint64_t abs_addr;
+ int i;
+
+ real_addr = fix_address(env, real_addr);
+ abs_addr = mmu_real2abs(env, real_addr) & TARGET_PAGE_MASK;
+ if (!address_space_access_valid(&address_space_memory, abs_addr,
+ TARGET_PAGE_SIZE, true)) {
+ program_interrupt(env, PGM_ADDRESSING, 4);
+ return 1;
+ }
+
+ /* Check low-address protection */
+ if ((env->cregs[0] & CR0_LOWPROT) && real_addr < 0x2000) {
+ program_interrupt(env, PGM_PROTECTION, 4);
+ return 1;
+ }
+
+ for (i = 0; i < TARGET_PAGE_SIZE; i += 8) {
+ stq_phys(cs->as, abs_addr + i, 0);
+ }
+
+ return 0;
+}
+
uint32_t HELPER(tprot)(uint64_t a1, uint64_t a2)
{
/* XXX implement */
diff --git a/target/s390x/mmu_helper.c b/target/s390x/mmu_helper.c
index b11a027..31eb9ef 100644
--- a/target/s390x/mmu_helper.c
+++ b/target/s390x/mmu_helper.c
@@ -108,7 +108,7 @@ static void trigger_page_fault(CPUS390XState *env,
target_ulong vaddr,
* Translate real address to absolute (= physical)
* address by taking care of the prefix mapping.
*/
-static target_ulong mmu_real2abs(CPUS390XState *env, target_ulong raddr)
+target_ulong mmu_real2abs(CPUS390XState *env, target_ulong raddr)
{
if (raddr < 0x2000) {
return raddr + env->psa; /* Map the lowcore. */
diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index 4c48c59..d6736e4 100644
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -4057,6 +4057,16 @@ static ExitStatus op_tcxb(DisasContext *s, DisasOps *o)
}
#ifndef CONFIG_USER_ONLY
+
+static ExitStatus op_testblock(DisasContext *s, DisasOps *o)
+{
+ check_privileged(s);
+ potential_page_fault(s);
+ gen_helper_testblock(cc_op, cpu_env, o->in2);
+ set_cc_static(s);
+ return NO_EXIT;
+}
+
static ExitStatus op_tprot(DisasContext *s, DisasOps *o)
{
potential_page_fault(s);
@@ -4064,6 +4074,7 @@ static ExitStatus op_tprot(DisasContext *s, DisasOps *o)
set_cc_static(s);
return NO_EXIT;
}
+
#endif
static ExitStatus op_tr(DisasContext *s, DisasOps *o)
--
1.8.3.1
