s390x/kvm: factor out SIGP code into sigp.c

We want to use the same code base for TCG, so let's cleanly factor it
out.

The sigp mutex is currently not really needed, as everything is
protected by the iothread mutex. But this could change later, so leave
it in place and initialize it properly from common code.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170928203708.9376-17-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

1 files changed, 366 insertions, 0 deletions

diff --git a/target/s390x/sigp.c b/target/s390x/sigp.c
new file mode 100644
index 0000000..4813123
--- /dev/null
+++ b/target/s390x/sigp.c
@@ -0,0 +1,366 @@
+/*
+ * s390x SIGP instruction handling
+ *
+ * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
+ * Copyright IBM Corp. 2012
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "cpu.h"
+#include "internal.h"
+#include "sysemu/hw_accel.h"
+#include "exec/address-spaces.h"
+#include "sysemu/sysemu.h"
+#include "trace.h"
+
+QemuMutex qemu_sigp_mutex;
+
+typedef struct SigpInfo {
+    uint64_t param;
+    int cc;
+    uint64_t *status_reg;
+} SigpInfo;
+
+static void set_sigp_status(SigpInfo *si, uint64_t status)
+{
+    *si->status_reg &= 0xffffffff00000000ULL;
+    *si->status_reg |= status;
+    si->cc = SIGP_CC_STATUS_STORED;
+}
+
+static void sigp_start(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+
+    if (s390_cpu_get_state(cpu) != CPU_STATE_STOPPED) {
+        si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+        return;
+    }
+
+    s390_cpu_set_state(CPU_STATE_OPERATING, cpu);
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_stop(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+
+    if (s390_cpu_get_state(cpu) != CPU_STATE_OPERATING) {
+        si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+        return;
+    }
+
+    /* disabled wait - sleeping in user space */
+    if (cs->halted) {
+        s390_cpu_set_state(CPU_STATE_STOPPED, cpu);
+    } else {
+        /* execute the stop function */
+        cpu->env.sigp_order = SIGP_STOP;
+        cpu_inject_stop(cpu);
+    }
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_stop_and_store_status(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+
+    /* disabled wait - sleeping in user space */
+    if (s390_cpu_get_state(cpu) == CPU_STATE_OPERATING && cs->halted) {
+        s390_cpu_set_state(CPU_STATE_STOPPED, cpu);
+    }
+
+    switch (s390_cpu_get_state(cpu)) {
+    case CPU_STATE_OPERATING:
+        cpu->env.sigp_order = SIGP_STOP_STORE_STATUS;
+        cpu_inject_stop(cpu);
+        /* store will be performed when handling the stop intercept */
+        break;
+    case CPU_STATE_STOPPED:
+        /* already stopped, just store the status */
+        cpu_synchronize_state(cs);
+        s390_store_status(cpu, S390_STORE_STATUS_DEF_ADDR, true);
+        break;
+    }
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_store_status_at_address(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+    uint32_t address = si->param & 0x7ffffe00u;
+
+    /* cpu has to be stopped */
+    if (s390_cpu_get_state(cpu) != CPU_STATE_STOPPED) {
+        set_sigp_status(si, SIGP_STAT_INCORRECT_STATE);
+        return;
+    }
+
+    cpu_synchronize_state(cs);
+
+    if (s390_store_status(cpu, address, false)) {
+        set_sigp_status(si, SIGP_STAT_INVALID_PARAMETER);
+        return;
+    }
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+#define ADTL_SAVE_LC_MASK  0xfUL
+static void sigp_store_adtl_status(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+    uint8_t lc = si->param & ADTL_SAVE_LC_MASK;
+    hwaddr addr = si->param & ~ADTL_SAVE_LC_MASK;
+    hwaddr len = 1UL << (lc ? lc : 10);
+
+    if (!s390_has_feat(S390_FEAT_VECTOR) &&
+        !s390_has_feat(S390_FEAT_GUARDED_STORAGE)) {
+        set_sigp_status(si, SIGP_STAT_INVALID_ORDER);
+        return;
+    }
+
+    /* cpu has to be stopped */
+    if (s390_cpu_get_state(cpu) != CPU_STATE_STOPPED) {
+        set_sigp_status(si, SIGP_STAT_INCORRECT_STATE);
+        return;
+    }
+
+    /* address must be aligned to length */
+    if (addr & (len - 1)) {
+        set_sigp_status(si, SIGP_STAT_INVALID_PARAMETER);
+        return;
+    }
+
+    /* no GS: only lc == 0 is valid */
+    if (!s390_has_feat(S390_FEAT_GUARDED_STORAGE) &&
+        lc != 0) {
+        set_sigp_status(si, SIGP_STAT_INVALID_PARAMETER);
+        return;
+    }
+
+    /* GS: 0, 10, 11, 12 are valid */
+    if (s390_has_feat(S390_FEAT_GUARDED_STORAGE) &&
+        lc != 0 &&
+        lc != 10 &&
+        lc != 11 &&
+        lc != 12) {
+        set_sigp_status(si, SIGP_STAT_INVALID_PARAMETER);
+        return;
+    }
+
+    cpu_synchronize_state(cs);
+
+    if (s390_store_adtl_status(cpu, addr, len)) {
+        set_sigp_status(si, SIGP_STAT_INVALID_PARAMETER);
+        return;
+    }
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_restart(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+
+    switch (s390_cpu_get_state(cpu)) {
+    case CPU_STATE_STOPPED:
+        /* the restart irq has to be delivered prior to any other pending irq */
+        cpu_synchronize_state(cs);
+        do_restart_interrupt(&cpu->env);
+        s390_cpu_set_state(CPU_STATE_OPERATING, cpu);
+        break;
+    case CPU_STATE_OPERATING:
+        cpu_inject_restart(cpu);
+        break;
+    }
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_initial_cpu_reset(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
+    SigpInfo *si = arg.host_ptr;
+
+    cpu_synchronize_state(cs);
+    scc->initial_cpu_reset(cs);
+    cpu_synchronize_post_reset(cs);
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_cpu_reset(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
+    SigpInfo *si = arg.host_ptr;
+
+    cpu_synchronize_state(cs);
+    scc->cpu_reset(cs);
+    cpu_synchronize_post_reset(cs);
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static void sigp_set_prefix(CPUState *cs, run_on_cpu_data arg)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    SigpInfo *si = arg.host_ptr;
+    uint32_t addr = si->param & 0x7fffe000u;
+
+    cpu_synchronize_state(cs);
+
+    if (!address_space_access_valid(&address_space_memory, addr,
+                                    sizeof(struct LowCore), false)) {
+        set_sigp_status(si, SIGP_STAT_INVALID_PARAMETER);
+        return;
+    }
+
+    /* cpu has to be stopped */
+    if (s390_cpu_get_state(cpu) != CPU_STATE_STOPPED) {
+        set_sigp_status(si, SIGP_STAT_INCORRECT_STATE);
+        return;
+    }
+
+    cpu->env.psa = addr;
+    cpu_synchronize_post_init(cs);
+    si->cc = SIGP_CC_ORDER_CODE_ACCEPTED;
+}
+
+static int handle_sigp_single_dst(S390CPU *dst_cpu, uint8_t order,
+                                  uint64_t param, uint64_t *status_reg)
+{
+    SigpInfo si = {
+        .param = param,
+        .status_reg = status_reg,
+    };
+
+    /* cpu available? */
+    if (dst_cpu == NULL) {
+        return SIGP_CC_NOT_OPERATIONAL;
+    }
+
+    /* only resets can break pending orders */
+    if (dst_cpu->env.sigp_order != 0 &&
+        order != SIGP_CPU_RESET &&
+        order != SIGP_INITIAL_CPU_RESET) {
+        return SIGP_CC_BUSY;
+    }
+
+    switch (order) {
+    case SIGP_START:
+        run_on_cpu(CPU(dst_cpu), sigp_start, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_STOP:
+        run_on_cpu(CPU(dst_cpu), sigp_stop, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_RESTART:
+        run_on_cpu(CPU(dst_cpu), sigp_restart, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_STOP_STORE_STATUS:
+        run_on_cpu(CPU(dst_cpu), sigp_stop_and_store_status, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_STORE_STATUS_ADDR:
+        run_on_cpu(CPU(dst_cpu), sigp_store_status_at_address, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_STORE_ADTL_STATUS:
+        run_on_cpu(CPU(dst_cpu), sigp_store_adtl_status, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_SET_PREFIX:
+        run_on_cpu(CPU(dst_cpu), sigp_set_prefix, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_INITIAL_CPU_RESET:
+        run_on_cpu(CPU(dst_cpu), sigp_initial_cpu_reset, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    case SIGP_CPU_RESET:
+        run_on_cpu(CPU(dst_cpu), sigp_cpu_reset, RUN_ON_CPU_HOST_PTR(&si));
+        break;
+    default:
+        set_sigp_status(&si, SIGP_STAT_INVALID_ORDER);
+    }
+
+    return si.cc;
+}
+
+static int sigp_set_architecture(S390CPU *cpu, uint32_t param,
+                                 uint64_t *status_reg)
+{
+    CPUState *cur_cs;
+    S390CPU *cur_cpu;
+    bool all_stopped = true;
+
+    CPU_FOREACH(cur_cs) {
+        cur_cpu = S390_CPU(cur_cs);
+
+        if (cur_cpu == cpu) {
+            continue;
+        }
+        if (s390_cpu_get_state(cur_cpu) != CPU_STATE_STOPPED) {
+            all_stopped = false;
+        }
+    }
+
+    *status_reg &= 0xffffffff00000000ULL;
+
+    /* Reject set arch order, with czam we're always in z/Arch mode. */
+    *status_reg |= (all_stopped ? SIGP_STAT_INVALID_PARAMETER :
+                    SIGP_STAT_INCORRECT_STATE);
+    return SIGP_CC_STATUS_STORED;
+}
+
+int handle_sigp(CPUS390XState *env, uint8_t order, uint64_t r1, uint64_t r3)
+{
+    uint64_t *status_reg = &env->regs[r1];
+    uint64_t param = (r1 % 2) ? env->regs[r1] : env->regs[r1 + 1];
+    S390CPU *cpu = s390_env_get_cpu(env);
+    S390CPU *dst_cpu = NULL;
+    int ret;
+
+    if (qemu_mutex_trylock(&qemu_sigp_mutex)) {
+        ret = SIGP_CC_BUSY;
+        goto out;
+    }
+
+    switch (order) {
+    case SIGP_SET_ARCH:
+        ret = sigp_set_architecture(cpu, param, status_reg);
+        break;
+    default:
+        /* all other sigp orders target a single vcpu */
+        dst_cpu = s390_cpu_addr2state(env->regs[r3]);
+        ret = handle_sigp_single_dst(dst_cpu, order, param, status_reg);
+    }
+    qemu_mutex_unlock(&qemu_sigp_mutex);
+
+out:
+    trace_sigp_finished(order, CPU(cpu)->cpu_index,
+                        dst_cpu ? CPU(dst_cpu)->cpu_index : -1, ret);
+    g_assert(ret >= 0);
+
+    return ret;
+}
+
+int s390_cpu_restart(S390CPU *cpu)
+{
+    SigpInfo si = {};
+
+    if (tcg_enabled()) {
+        /* FIXME TCG */
+        return -ENOSYS;
+    }
+
+    run_on_cpu(CPU(cpu), sigp_restart, RUN_ON_CPU_HOST_PTR(&si));
+    return 0;
+}
+
+void s390_init_sigp(void)
+{
+    qemu_mutex_init(&qemu_sigp_mutex);
+}