Merge tag 'pull-request-2023-10-20' of https://gitlab.com/thuth/qemu into staging

* s390x CPU topology support
* Simplify the KVM register synchronization code
* Disable the analyze-migration.py test on s390x

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* tag 'pull-request-2023-10-20' of https://gitlab.com/thuth/qemu: (24 commits)
  tests/qtest/migration-test: Disable the analyze-migration.py test on s390x
  target/s390x/kvm: Simplify the GPRs, ACRs, CRs and prefix synchronization code
  target/s390x/kvm: Turn KVM_CAP_SYNC_REGS into a hard requirement
  tests/avocado: s390x cpu topology bad move
  tests/avocado: s390x cpu topology dedicated errors
  tests/avocado: s390x cpu topology test socket full
  tests/avocado: s390x cpu topology test dedicated CPU
  tests/avocado: s390x cpu topology entitlement tests
  tests/avocado: s390x cpu topology polarization
  tests/avocado: s390x cpu topology core
  docs/s390x/cpu topology: document s390x cpu topology
  qapi/s390x/cpu topology: add query-s390x-cpu-polarization command
  qapi/s390x/cpu topology: CPU_POLARIZATION_CHANGE QAPI event
  machine: adding s390 topology to info hotpluggable-cpus
  machine: adding s390 topology to query-cpu-fast
  qapi/s390x/cpu topology: set-cpu-topology qmp command
  target/s390x/cpu topology: activate CPU topology
  s390x/cpu topology: interception of PTF instruction
  s390x/cpu topology: resetting the Topology-Change-Report
  s390x/sclp: reporting the maximum nested topology entries
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

4 files changed, 502 insertions, 2 deletions

diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
new file mode 100644
index 0000000000..f16bdf65fa
--- /dev/null
+++ b/hw/s390x/cpu-topology.c
@@ -0,0 +1,469 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * CPU Topology
+ *
+ * Copyright IBM Corp. 2022, 2023
+ * Author(s): Pierre Morel <pmorel@linux.ibm.com>
+ *
+ * S390 topology handling can be divided in two parts:
+ *
+ * - The first part in this file is taking care of all common functions
+ *   used by KVM and TCG to create and modify the topology.
+ *
+ * - The second part, building the topology information data for the
+ *   guest with CPU and KVM specificity will be implemented inside
+ *   the target/s390/kvm sub tree.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "hw/qdev-properties.h"
+#include "hw/boards.h"
+#include "target/s390x/cpu.h"
+#include "hw/s390x/s390-virtio-ccw.h"
+#include "hw/s390x/cpu-topology.h"
+#include "qapi/qapi-commands-machine-target.h"
+#include "qapi/qapi-events-machine-target.h"
+
+/*
+ * s390_topology is used to keep the topology information.
+ * .cores_per_socket: tracks information on the count of cores
+ *                    per socket.
+ * .polarization: tracks machine polarization.
+ */
+S390Topology s390_topology = {
+    /* will be initialized after the CPU model is realized */
+    .cores_per_socket = NULL,
+    .polarization = S390_CPU_POLARIZATION_HORIZONTAL,
+};
+
+/**
+ * s390_socket_nb:
+ * @cpu: s390x CPU
+ *
+ * Returns the socket number used inside the cores_per_socket array
+ * for a topology tree entry
+ */
+static int s390_socket_nb_from_ids(int drawer_id, int book_id, int socket_id)
+{
+    return (drawer_id * current_machine->smp.books + book_id) *
+           current_machine->smp.sockets + socket_id;
+}
+
+/**
+ * s390_socket_nb:
+ * @cpu: s390x CPU
+ *
+ * Returns the socket number used inside the cores_per_socket array
+ * for a cpu.
+ */
+static int s390_socket_nb(S390CPU *cpu)
+{
+    return s390_socket_nb_from_ids(cpu->env.drawer_id, cpu->env.book_id,
+                                   cpu->env.socket_id);
+}
+
+/**
+ * s390_has_topology:
+ *
+ * Return: true if the topology is supported by the machine.
+ */
+bool s390_has_topology(void)
+{
+    return s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY);
+}
+
+/**
+ * s390_topology_init:
+ * @ms: the machine state where the machine topology is defined
+ *
+ * Keep track of the machine topology.
+ *
+ * Allocate an array to keep the count of cores per socket.
+ * The index of the array starts at socket 0 from book 0 and
+ * drawer 0 up to the maximum allowed by the machine topology.
+ */
+static void s390_topology_init(MachineState *ms)
+{
+    CpuTopology *smp = &ms->smp;
+
+    s390_topology.cores_per_socket = g_new0(uint8_t, smp->sockets *
+                                            smp->books * smp->drawers);
+}
+
+/*
+ * s390_handle_ptf:
+ *
+ * @register 1: contains the function code
+ *
+ * Function codes 0 (horizontal) and 1 (vertical) define the CPU
+ * polarization requested by the guest.
+ *
+ * Function code 2 is handling topology changes and is interpreted
+ * by the SIE.
+ */
+void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra)
+{
+    CpuS390Polarization polarization;
+    CPUS390XState *env = &cpu->env;
+    uint64_t reg = env->regs[r1];
+    int fc = reg & S390_TOPO_FC_MASK;
+
+    if (!s390_has_feat(S390_FEAT_CONFIGURATION_TOPOLOGY)) {
+        s390_program_interrupt(env, PGM_OPERATION, ra);
+        return;
+    }
+
+    if (env->psw.mask & PSW_MASK_PSTATE) {
+        s390_program_interrupt(env, PGM_PRIVILEGED, ra);
+        return;
+    }
+
+    if (reg & ~S390_TOPO_FC_MASK) {
+        s390_program_interrupt(env, PGM_SPECIFICATION, ra);
+        return;
+    }
+
+    polarization = S390_CPU_POLARIZATION_VERTICAL;
+    switch (fc) {
+    case 0:
+        polarization = S390_CPU_POLARIZATION_HORIZONTAL;
+        /* fallthrough */
+    case 1:
+        if (s390_topology.polarization == polarization) {
+            env->regs[r1] |= S390_PTF_REASON_DONE;
+            setcc(cpu, 2);
+        } else {
+            s390_topology.polarization = polarization;
+            s390_cpu_topology_set_changed(true);
+            qapi_event_send_cpu_polarization_change(polarization);
+            setcc(cpu, 0);
+        }
+        break;
+    default:
+        /* Note that fc == 2 is interpreted by the SIE */
+        s390_program_interrupt(env, PGM_SPECIFICATION, ra);
+    }
+}
+
+/**
+ * s390_topology_reset:
+ *
+ * Generic reset for CPU topology, calls s390_topology_reset()
+ * to reset the kernel Modified Topology Change Record.
+ */
+void s390_topology_reset(void)
+{
+    s390_cpu_topology_set_changed(false);
+    s390_topology.polarization = S390_CPU_POLARIZATION_HORIZONTAL;
+}
+
+/**
+ * s390_topology_cpu_default:
+ * @cpu: pointer to a S390CPU
+ * @errp: Error pointer
+ *
+ * Setup the default topology if no attributes are already set.
+ * Passing a CPU with some, but not all, attributes set is considered
+ * an error.
+ *
+ * The function calculates the (drawer_id, book_id, socket_id)
+ * topology by filling the cores starting from the first socket
+ * (0, 0, 0) up to the last (smp->drawers, smp->books, smp->sockets).
+ *
+ * CPU type and dedication have defaults values set in the
+ * s390x_cpu_properties, entitlement must be adjust depending on the
+ * dedication.
+ *
+ * Returns false if it is impossible to setup a default topology
+ * true otherwise.
+ */
+static bool s390_topology_cpu_default(S390CPU *cpu, Error **errp)
+{
+    CpuTopology *smp = &current_machine->smp;
+    CPUS390XState *env = &cpu->env;
+
+    /* All geometry topology attributes must be set or all unset */
+    if ((env->socket_id < 0 || env->book_id < 0 || env->drawer_id < 0) &&
+        (env->socket_id >= 0 || env->book_id >= 0 || env->drawer_id >= 0)) {
+        error_setg(errp,
+                   "Please define all or none of the topology geometry attributes");
+        return false;
+    }
+
+    /* If one value is unset all are unset -> calculate defaults */
+    if (env->socket_id < 0) {
+        env->socket_id = s390_std_socket(env->core_id, smp);
+        env->book_id = s390_std_book(env->core_id, smp);
+        env->drawer_id = s390_std_drawer(env->core_id, smp);
+    }
+
+    /*
+     * When the user specifies the entitlement as 'auto' on the command line,
+     * QEMU will set the entitlement as:
+     * Medium when the CPU is not dedicated.
+     * High when dedicated is true.
+     */
+    if (env->entitlement == S390_CPU_ENTITLEMENT_AUTO) {
+        if (env->dedicated) {
+            env->entitlement = S390_CPU_ENTITLEMENT_HIGH;
+        } else {
+            env->entitlement = S390_CPU_ENTITLEMENT_MEDIUM;
+        }
+    }
+    return true;
+}
+
+/**
+ * s390_topology_check:
+ * @socket_id: socket to check
+ * @book_id: book to check
+ * @drawer_id: drawer to check
+ * @entitlement: entitlement to check
+ * @dedicated: dedication to check
+ * @errp: Error pointer
+ *
+ * The function checks if the topology
+ * attributes fits inside the system topology.
+ *
+ * Returns false if the specified topology does not match with
+ * the machine topology.
+ */
+static bool s390_topology_check(uint16_t socket_id, uint16_t book_id,
+                                uint16_t drawer_id, uint16_t entitlement,
+                                bool dedicated, Error **errp)
+{
+    CpuTopology *smp = &current_machine->smp;
+
+    if (socket_id >= smp->sockets) {
+        error_setg(errp, "Unavailable socket: %d", socket_id);
+        return false;
+    }
+    if (book_id >= smp->books) {
+        error_setg(errp, "Unavailable book: %d", book_id);
+        return false;
+    }
+    if (drawer_id >= smp->drawers) {
+        error_setg(errp, "Unavailable drawer: %d", drawer_id);
+        return false;
+    }
+    if (entitlement >= S390_CPU_ENTITLEMENT__MAX) {
+        error_setg(errp, "Unknown entitlement: %d", entitlement);
+        return false;
+    }
+    if (dedicated && (entitlement == S390_CPU_ENTITLEMENT_LOW ||
+                      entitlement == S390_CPU_ENTITLEMENT_MEDIUM)) {
+        error_setg(errp, "A dedicated CPU implies high entitlement");
+        return false;
+    }
+    return true;
+}
+
+/**
+ * s390_topology_need_report
+ * @cpu: Current cpu
+ * @drawer_id: future drawer ID
+ * @book_id: future book ID
+ * @socket_id: future socket ID
+ * @entitlement: future entitlement
+ * @dedicated: future dedicated
+ *
+ * A modified topology change report is needed if the topology
+ * tree or the topology attributes change.
+ */
+static bool s390_topology_need_report(S390CPU *cpu, int drawer_id,
+                                      int book_id, int socket_id,
+                                      uint16_t entitlement, bool dedicated)
+{
+    return cpu->env.drawer_id != drawer_id ||
+           cpu->env.book_id != book_id ||
+           cpu->env.socket_id != socket_id ||
+           cpu->env.entitlement != entitlement ||
+           cpu->env.dedicated != dedicated;
+}
+
+/**
+ * s390_update_cpu_props:
+ * @ms: the machine state
+ * @cpu: the CPU for which to update the properties from the environment.
+ *
+ */
+static void s390_update_cpu_props(MachineState *ms, S390CPU *cpu)
+{
+    CpuInstanceProperties *props;
+
+    props = &ms->possible_cpus->cpus[cpu->env.core_id].props;
+
+    props->socket_id = cpu->env.socket_id;
+    props->book_id = cpu->env.book_id;
+    props->drawer_id = cpu->env.drawer_id;
+}
+
+/**
+ * s390_topology_setup_cpu:
+ * @ms: MachineState used to initialize the topology structure on
+ *      first call.
+ * @cpu: the new S390CPU to insert in the topology structure
+ * @errp: the error pointer
+ *
+ * Called from CPU hotplug to check and setup the CPU attributes
+ * before the CPU is inserted in the topology.
+ * There is no need to update the MTCR explicitly here because it
+ * will be updated by KVM on creation of the new CPU.
+ */
+void s390_topology_setup_cpu(MachineState *ms, S390CPU *cpu, Error **errp)
+{
+    int entry;
+
+    /*
+     * We do not want to initialize the topology if the CPU model
+     * does not support topology, consequently, we have to wait for
+     * the first CPU to be realized, which realizes the CPU model
+     * to initialize the topology structures.
+     *
+     * s390_topology_setup_cpu() is called from the CPU hotplug.
+     */
+    if (!s390_topology.cores_per_socket) {
+        s390_topology_init(ms);
+    }
+
+    if (!s390_topology_cpu_default(cpu, errp)) {
+        return;
+    }
+
+    if (!s390_topology_check(cpu->env.socket_id, cpu->env.book_id,
+                             cpu->env.drawer_id, cpu->env.entitlement,
+                             cpu->env.dedicated, errp)) {
+        return;
+    }
+
+    /* Do we still have space in the socket */
+    entry = s390_socket_nb(cpu);
+    if (s390_topology.cores_per_socket[entry] >= ms->smp.cores) {
+        error_setg(errp, "No more space on this socket");
+        return;
+    }
+
+    /* Update the count of cores in sockets */
+    s390_topology.cores_per_socket[entry] += 1;
+
+    /* topology tree is reflected in props */
+    s390_update_cpu_props(ms, cpu);
+}
+
+static void s390_change_topology(uint16_t core_id,
+                                 bool has_socket_id, uint16_t socket_id,
+                                 bool has_book_id, uint16_t book_id,
+                                 bool has_drawer_id, uint16_t drawer_id,
+                                 bool has_entitlement,
+                                 CpuS390Entitlement entitlement,
+                                 bool has_dedicated, bool dedicated,
+                                 Error **errp)
+{
+    MachineState *ms = current_machine;
+    int old_socket_entry;
+    int new_socket_entry;
+    bool report_needed;
+    S390CPU *cpu;
+
+    cpu = s390_cpu_addr2state(core_id);
+    if (!cpu) {
+        error_setg(errp, "Core-id %d does not exist!", core_id);
+        return;
+    }
+
+    /* Get attributes not provided from cpu and verify the new topology */
+    if (!has_socket_id) {
+        socket_id = cpu->env.socket_id;
+    }
+    if (!has_book_id) {
+        book_id = cpu->env.book_id;
+    }
+    if (!has_drawer_id) {
+        drawer_id = cpu->env.drawer_id;
+    }
+    if (!has_dedicated) {
+        dedicated = cpu->env.dedicated;
+    }
+
+    /*
+     * When the user specifies the entitlement as 'auto' on the command line,
+     * QEMU will set the entitlement as:
+     * Medium when the CPU is not dedicated.
+     * High when dedicated is true.
+     */
+    if (!has_entitlement || entitlement == S390_CPU_ENTITLEMENT_AUTO) {
+        if (dedicated) {
+            entitlement = S390_CPU_ENTITLEMENT_HIGH;
+        } else {
+            entitlement = S390_CPU_ENTITLEMENT_MEDIUM;
+        }
+    }
+
+    if (!s390_topology_check(socket_id, book_id, drawer_id,
+                             entitlement, dedicated, errp)) {
+        return;
+    }
+
+    /* Check for space on new socket */
+    old_socket_entry = s390_socket_nb(cpu);
+    new_socket_entry = s390_socket_nb_from_ids(drawer_id, book_id, socket_id);
+
+    if (new_socket_entry != old_socket_entry) {
+        if (s390_topology.cores_per_socket[new_socket_entry] >=
+            ms->smp.cores) {
+            error_setg(errp, "No more space on this socket");
+            return;
+        }
+        /* Update the count of cores in sockets */
+        s390_topology.cores_per_socket[new_socket_entry] += 1;
+        s390_topology.cores_per_socket[old_socket_entry] -= 1;
+    }
+
+    /* Check if we will need to report the modified topology */
+    report_needed = s390_topology_need_report(cpu, drawer_id, book_id,
+                                              socket_id, entitlement,
+                                              dedicated);
+
+    /* All checks done, report new topology into the vCPU */
+    cpu->env.drawer_id = drawer_id;
+    cpu->env.book_id = book_id;
+    cpu->env.socket_id = socket_id;
+    cpu->env.dedicated = dedicated;
+    cpu->env.entitlement = entitlement;
+
+    /* topology tree is reflected in props */
+    s390_update_cpu_props(ms, cpu);
+
+    /* Advertise the topology change */
+    if (report_needed) {
+        s390_cpu_topology_set_changed(true);
+    }
+}
+
+void qmp_set_cpu_topology(uint16_t core,
+                          bool has_socket, uint16_t socket,
+                          bool has_book, uint16_t book,
+                          bool has_drawer, uint16_t drawer,
+                          bool has_entitlement, CpuS390Entitlement entitlement,
+                          bool has_dedicated, bool dedicated,
+                          Error **errp)
+{
+    if (!s390_has_topology()) {
+        error_setg(errp, "This machine doesn't support topology");
+        return;
+    }
+
+    s390_change_topology(core, has_socket, socket, has_book, book,
+                         has_drawer, drawer, has_entitlement, entitlement,
+                         has_dedicated, dedicated, errp);
+}
+
+CpuPolarizationInfo *qmp_query_s390x_cpu_polarization(Error **errp)
+{
+    CpuPolarizationInfo *info = g_new0(CpuPolarizationInfo, 1);
+
+    info->polarization = s390_topology.polarization;
+    return info;
+}
diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build
index 6fd096813a..482fd13420 100644
--- a/hw/s390x/meson.build
+++ b/hw/s390x/meson.build
@@ -23,6 +23,7 @@ s390x_ss.add(when: 'CONFIG_KVM', if_true: files(
   's390-skeys-kvm.c',
   's390-stattrib-kvm.c',
   's390-pci-kvm.c',
+  'cpu-topology.c',
 ))
 s390x_ss.add(when: 'CONFIG_TCG', if_true: files(
   'tod-tcg.c',
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 2d75f2131f..6012165d41 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -45,6 +45,7 @@
 #include "target/s390x/kvm/pv.h"
 #include "migration/blocker.h"
 #include "qapi/visitor.h"
+#include "hw/s390x/cpu-topology.h"
 
 static Error *pv_mig_blocker;
 
@@ -123,6 +124,9 @@ static void subsystem_reset(void)
             device_cold_reset(dev);
         }
     }
+    if (s390_has_topology()) {
+        s390_topology_reset();
+    }
 }
 
 static int virtio_ccw_hcall_notify(const uint64_t *args)
@@ -309,10 +313,18 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev,
 {
     MachineState *ms = MACHINE(hotplug_dev);
     S390CPU *cpu = S390_CPU(dev);
+    ERRP_GUARD();
 
     g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu);
     ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev);
 
+    if (s390_has_topology()) {
+        s390_topology_setup_cpu(ms, cpu, errp);
+        if (*errp) {
+            return;
+        }
+    }
+
     if (dev->hotplugged) {
         raise_irq_cpu_hotplug();
     }
@@ -562,11 +574,20 @@ static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms)
                                   sizeof(CPUArchId) * max_cpus);
     ms->possible_cpus->len = max_cpus;
     for (i = 0; i < ms->possible_cpus->len; i++) {
+        CpuInstanceProperties *props = &ms->possible_cpus->cpus[i].props;
+
         ms->possible_cpus->cpus[i].type = ms->cpu_type;
         ms->possible_cpus->cpus[i].vcpus_count = 1;
         ms->possible_cpus->cpus[i].arch_id = i;
-        ms->possible_cpus->cpus[i].props.has_core_id = true;
-        ms->possible_cpus->cpus[i].props.core_id = i;
+
+        props->has_core_id = true;
+        props->core_id = i;
+        props->has_socket_id = true;
+        props->socket_id = s390_std_socket(i, &ms->smp);
+        props->has_book_id = true;
+        props->book_id = s390_std_book(i, &ms->smp);
+        props->has_drawer_id = true;
+        props->drawer_id = s390_std_drawer(i, &ms->smp);
     }
 
     return ms->possible_cpus;
@@ -744,6 +765,8 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
     mc->no_sdcard = 1;
     mc->max_cpus = S390_MAX_CPUS;
     mc->has_hotpluggable_cpus = true;
+    mc->smp_props.books_supported = true;
+    mc->smp_props.drawers_supported = true;
     assert(!mc->get_hotplug_handler);
     mc->get_hotplug_handler = s390_get_hotplug_handler;
     mc->cpu_index_to_instance_props = s390_cpu_index_to_props;
@@ -853,6 +876,8 @@ static void ccw_machine_8_1_class_options(MachineClass *mc)
 {
     ccw_machine_8_2_class_options(mc);
     compat_props_add(mc->compat_props, hw_compat_8_1, hw_compat_8_1_len);
+    mc->smp_props.drawers_supported = false;
+    mc->smp_props.books_supported = false;
 }
 DEFINE_CCW_MACHINE(8_1, "8.1", false);
 
diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index eff74479f4..d339cbb7e4 100644
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -20,6 +20,7 @@
 #include "hw/s390x/event-facility.h"
 #include "hw/s390x/s390-pci-bus.h"
 #include "hw/s390x/ipl.h"
+#include "hw/s390x/cpu-topology.h"
 
 static inline SCLPDevice *get_sclp_device(void)
 {
@@ -123,6 +124,10 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
         return;
     }
 
+    if (s390_has_topology()) {
+        read_info->stsi_parm = SCLP_READ_SCP_INFO_MNEST;
+    }
+
     /* CPU information */
     prepare_cpu_entries(machine, entries_start, &cpu_count);
     read_info->entries_cpu = cpu_to_be16(cpu_count);