1 files changed, 722 insertions, 0 deletions
diff --git a/migration/options.c b/migration/options.c
new file mode 100644
index 0000000..8e8753d
--- /dev/null
+++ b/migration/options.c
@@ -0,0 +1,722 @@
+/*
+ * QEMU migration capabilities
+ *
+ * Copyright (c) 2012-2023 Red Hat Inc
+ *
+ * Authors:
+ *   Orit Wasserman <owasserm@redhat.com>
+ *   Juan Quintela <quintela@redhat.com>
+ *
+ * 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 "qapi/clone-visitor.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-migration.h"
+#include "qapi/qapi-visit-migration.h"
+#include "qapi/qmp/qerror.h"
+#include "sysemu/runstate.h"
+#include "migration/misc.h"
+#include "migration.h"
+#include "ram.h"
+#include "options.h"
+
+bool migrate_auto_converge(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_AUTO_CONVERGE];
+}
+
+bool migrate_background_snapshot(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_BACKGROUND_SNAPSHOT];
+}
+
+bool migrate_block(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_BLOCK];
+}
+
+bool migrate_colo(void)
+{
+    MigrationState *s = migrate_get_current();
+    return s->capabilities[MIGRATION_CAPABILITY_X_COLO];
+}
+
+bool migrate_compress(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_COMPRESS];
+}
+
+bool migrate_dirty_bitmaps(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_DIRTY_BITMAPS];
+}
+
+bool migrate_events(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_EVENTS];
+}
+
+bool migrate_ignore_shared(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_X_IGNORE_SHARED];
+}
+
+bool migrate_late_block_activate(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_LATE_BLOCK_ACTIVATE];
+}
+
+bool migrate_multifd(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_MULTIFD];
+}
+
+bool migrate_pause_before_switchover(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_PAUSE_BEFORE_SWITCHOVER];
+}
+
+bool migrate_postcopy_blocktime(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_POSTCOPY_BLOCKTIME];
+}
+
+bool migrate_postcopy_preempt(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_POSTCOPY_PREEMPT];
+}
+
+bool migrate_postcopy_ram(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM];
+}
+
+bool migrate_rdma_pin_all(void)
+{
+    MigrationState *s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_RDMA_PIN_ALL];
+}
+
+bool migrate_release_ram(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_RELEASE_RAM];
+}
+
+bool migrate_return_path(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_RETURN_PATH];
+}
+
+bool migrate_validate_uuid(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_VALIDATE_UUID];
+}
+
+bool migrate_xbzrle(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_XBZRLE];
+}
+
+bool migrate_zero_blocks(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_ZERO_BLOCKS];
+}
+
+bool migrate_zero_copy_send(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->capabilities[MIGRATION_CAPABILITY_ZERO_COPY_SEND];
+}
+
+/* pseudo capabilities */
+
+bool migrate_postcopy(void)
+{
+    return migrate_postcopy_ram() || migrate_dirty_bitmaps();
+}
+
+typedef enum WriteTrackingSupport {
+    WT_SUPPORT_UNKNOWN = 0,
+    WT_SUPPORT_ABSENT,
+    WT_SUPPORT_AVAILABLE,
+    WT_SUPPORT_COMPATIBLE
+} WriteTrackingSupport;
+
+static
+WriteTrackingSupport migrate_query_write_tracking(void)
+{
+    /* Check if kernel supports required UFFD features */
+    if (!ram_write_tracking_available()) {
+        return WT_SUPPORT_ABSENT;
+    }
+    /*
+     * Check if current memory configuration is
+     * compatible with required UFFD features.
+     */
+    if (!ram_write_tracking_compatible()) {
+        return WT_SUPPORT_AVAILABLE;
+    }
+
+    return WT_SUPPORT_COMPATIBLE;
+}
+
+/* Migration capabilities set */
+struct MigrateCapsSet {
+    int size;                       /* Capability set size */
+    MigrationCapability caps[];     /* Variadic array of capabilities */
+};
+typedef struct MigrateCapsSet MigrateCapsSet;
+
+/* Define and initialize MigrateCapsSet */
+#define INITIALIZE_MIGRATE_CAPS_SET(_name, ...)   \
+    MigrateCapsSet _name = {    \
+        .size = sizeof((int []) { __VA_ARGS__ }) / sizeof(int), \
+        .caps = { __VA_ARGS__ } \
+    }
+
+/* Background-snapshot compatibility check list */
+static const
+INITIALIZE_MIGRATE_CAPS_SET(check_caps_background_snapshot,
+    MIGRATION_CAPABILITY_POSTCOPY_RAM,
+    MIGRATION_CAPABILITY_DIRTY_BITMAPS,
+    MIGRATION_CAPABILITY_POSTCOPY_BLOCKTIME,
+    MIGRATION_CAPABILITY_LATE_BLOCK_ACTIVATE,
+    MIGRATION_CAPABILITY_RETURN_PATH,
+    MIGRATION_CAPABILITY_MULTIFD,
+    MIGRATION_CAPABILITY_PAUSE_BEFORE_SWITCHOVER,
+    MIGRATION_CAPABILITY_AUTO_CONVERGE,
+    MIGRATION_CAPABILITY_RELEASE_RAM,
+    MIGRATION_CAPABILITY_RDMA_PIN_ALL,
+    MIGRATION_CAPABILITY_COMPRESS,
+    MIGRATION_CAPABILITY_XBZRLE,
+    MIGRATION_CAPABILITY_X_COLO,
+    MIGRATION_CAPABILITY_VALIDATE_UUID,
+    MIGRATION_CAPABILITY_ZERO_COPY_SEND);
+
+/**
+ * @migration_caps_check - check capability compatibility
+ *
+ * @old_caps: old capability list
+ * @new_caps: new capability list
+ * @errp: set *errp if the check failed, with reason
+ *
+ * Returns true if check passed, otherwise false.
+ */
+bool migrate_caps_check(bool *old_caps, bool *new_caps, Error **errp)
+{
+    MigrationIncomingState *mis = migration_incoming_get_current();
+
+#ifndef CONFIG_LIVE_BLOCK_MIGRATION
+    if (new_caps[MIGRATION_CAPABILITY_BLOCK]) {
+        error_setg(errp, "QEMU compiled without old-style (blk/-b, inc/-i) "
+                   "block migration");
+        error_append_hint(errp, "Use drive_mirror+NBD instead.\n");
+        return false;
+    }
+#endif
+
+#ifndef CONFIG_REPLICATION
+    if (new_caps[MIGRATION_CAPABILITY_X_COLO]) {
+        error_setg(errp, "QEMU compiled without replication module"
+                   " can't enable COLO");
+        error_append_hint(errp, "Please enable replication before COLO.\n");
+        return false;
+    }
+#endif
+
+    if (new_caps[MIGRATION_CAPABILITY_POSTCOPY_RAM]) {
+        /* This check is reasonably expensive, so only when it's being
+         * set the first time, also it's only the destination that needs
+         * special support.
+         */
+        if (!old_caps[MIGRATION_CAPABILITY_POSTCOPY_RAM] &&
+            runstate_check(RUN_STATE_INMIGRATE) &&
+            !postcopy_ram_supported_by_host(mis)) {
+            /* postcopy_ram_supported_by_host will have emitted a more
+             * detailed message
+             */
+            error_setg(errp, "Postcopy is not supported");
+            return false;
+        }
+
+        if (new_caps[MIGRATION_CAPABILITY_X_IGNORE_SHARED]) {
+            error_setg(errp, "Postcopy is not compatible with ignore-shared");
+            return false;
+        }
+    }
+
+    if (new_caps[MIGRATION_CAPABILITY_BACKGROUND_SNAPSHOT]) {
+        WriteTrackingSupport wt_support;
+        int idx;
+        /*
+         * Check if 'background-snapshot' capability is supported by
+         * host kernel and compatible with guest memory configuration.
+         */
+        wt_support = migrate_query_write_tracking();
+        if (wt_support < WT_SUPPORT_AVAILABLE) {
+            error_setg(errp, "Background-snapshot is not supported by host kernel");
+            return false;
+        }
+        if (wt_support < WT_SUPPORT_COMPATIBLE) {
+            error_setg(errp, "Background-snapshot is not compatible "
+                    "with guest memory configuration");
+            return false;
+        }
+
+        /*
+         * Check if there are any migration capabilities
+         * incompatible with 'background-snapshot'.
+         */
+        for (idx = 0; idx < check_caps_background_snapshot.size; idx++) {
+            int incomp_cap = check_caps_background_snapshot.caps[idx];
+            if (new_caps[incomp_cap]) {
+                error_setg(errp,
+                        "Background-snapshot is not compatible with %s",
+                        MigrationCapability_str(incomp_cap));
+                return false;
+            }
+        }
+    }
+
+#ifdef CONFIG_LINUX
+    if (new_caps[MIGRATION_CAPABILITY_ZERO_COPY_SEND] &&
+        (!new_caps[MIGRATION_CAPABILITY_MULTIFD] ||
+         new_caps[MIGRATION_CAPABILITY_COMPRESS] ||
+         new_caps[MIGRATION_CAPABILITY_XBZRLE] ||
+         migrate_multifd_compression() ||
+         migrate_use_tls())) {
+        error_setg(errp,
+                   "Zero copy only available for non-compressed non-TLS multifd migration");
+        return false;
+    }
+#else
+    if (new_caps[MIGRATION_CAPABILITY_ZERO_COPY_SEND]) {
+        error_setg(errp,
+                   "Zero copy currently only available on Linux");
+        return false;
+    }
+#endif
+
+    if (new_caps[MIGRATION_CAPABILITY_POSTCOPY_PREEMPT]) {
+        if (!new_caps[MIGRATION_CAPABILITY_POSTCOPY_RAM]) {
+            error_setg(errp, "Postcopy preempt requires postcopy-ram");
+            return false;
+        }
+
+        /*
+         * Preempt mode requires urgent pages to be sent in separate
+         * channel, OTOH compression logic will disorder all pages into
+         * different compression channels, which is not compatible with the
+         * preempt assumptions on channel assignments.
+         */
+        if (new_caps[MIGRATION_CAPABILITY_COMPRESS]) {
+            error_setg(errp, "Postcopy preempt not compatible with compress");
+            return false;
+        }
+    }
+
+    if (new_caps[MIGRATION_CAPABILITY_MULTIFD]) {
+        if (new_caps[MIGRATION_CAPABILITY_COMPRESS]) {
+            error_setg(errp, "Multifd is not compatible with compress");
+            return false;
+        }
+    }
+
+    return true;
+}
+
+bool migrate_cap_set(int cap, bool value, Error **errp)
+{
+    MigrationState *s = migrate_get_current();
+    bool new_caps[MIGRATION_CAPABILITY__MAX];
+
+    if (migration_is_running(s->state)) {
+        error_setg(errp, QERR_MIGRATION_ACTIVE);
+        return false;
+    }
+
+    memcpy(new_caps, s->capabilities, sizeof(new_caps));
+    new_caps[cap] = value;
+
+    if (!migrate_caps_check(s->capabilities, new_caps, errp)) {
+        return false;
+    }
+    s->capabilities[cap] = value;
+    return true;
+}
+
+MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp)
+{
+    MigrationCapabilityStatusList *head = NULL, **tail = &head;
+    MigrationCapabilityStatus *caps;
+    MigrationState *s = migrate_get_current();
+    int i;
+
+    for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
+#ifndef CONFIG_LIVE_BLOCK_MIGRATION
+        if (i == MIGRATION_CAPABILITY_BLOCK) {
+            continue;
+        }
+#endif
+        caps = g_malloc0(sizeof(*caps));
+        caps->capability = i;
+        caps->state = s->capabilities[i];
+        QAPI_LIST_APPEND(tail, caps);
+    }
+
+    return head;
+}
+
+void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
+                                  Error **errp)
+{
+    MigrationState *s = migrate_get_current();
+    MigrationCapabilityStatusList *cap;
+    bool new_caps[MIGRATION_CAPABILITY__MAX];
+
+    if (migration_is_running(s->state)) {
+        error_setg(errp, QERR_MIGRATION_ACTIVE);
+        return;
+    }
+
+    memcpy(new_caps, s->capabilities, sizeof(new_caps));
+    for (cap = params; cap; cap = cap->next) {
+        new_caps[cap->value->capability] = cap->value->state;
+    }
+
+    if (!migrate_caps_check(s->capabilities, new_caps, errp)) {
+        return;
+    }
+
+    for (cap = params; cap; cap = cap->next) {
+        s->capabilities[cap->value->capability] = cap->value->state;
+    }
+}
+
+/* parameters */
+
+bool migrate_block_incremental(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.block_incremental;
+}
+
+uint32_t migrate_checkpoint_delay(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.x_checkpoint_delay;
+}
+
+int migrate_compress_level(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.compress_level;
+}
+
+int migrate_compress_threads(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.compress_threads;
+}
+
+int migrate_compress_wait_thread(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.compress_wait_thread;
+}
+
+uint8_t migrate_cpu_throttle_increment(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.cpu_throttle_increment;
+}
+
+uint8_t migrate_cpu_throttle_initial(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.cpu_throttle_initial;
+}
+
+bool migrate_cpu_throttle_tailslow(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.cpu_throttle_tailslow;
+}
+
+int migrate_decompress_threads(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.decompress_threads;
+}
+
+uint8_t migrate_max_cpu_throttle(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.max_cpu_throttle;
+}
+
+uint64_t migrate_max_bandwidth(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.max_bandwidth;
+}
+
+int64_t migrate_max_postcopy_bandwidth(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.max_postcopy_bandwidth;
+}
+
+int migrate_multifd_channels(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.multifd_channels;
+}
+
+MultiFDCompression migrate_multifd_compression(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    assert(s->parameters.multifd_compression < MULTIFD_COMPRESSION__MAX);
+    return s->parameters.multifd_compression;
+}
+
+int migrate_multifd_zlib_level(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.multifd_zlib_level;
+}
+
+int migrate_multifd_zstd_level(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.multifd_zstd_level;
+}
+
+uint8_t migrate_throttle_trigger_threshold(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.throttle_trigger_threshold;
+}
+
+uint64_t migrate_xbzrle_cache_size(void)
+{
+    MigrationState *s;
+
+    s = migrate_get_current();
+
+    return s->parameters.xbzrle_cache_size;
+}
+
+/* parameters helpers */
+
+AnnounceParameters *migrate_announce_params(void)
+{
+    static AnnounceParameters ap;
+
+    MigrationState *s = migrate_get_current();
+
+    ap.initial = s->parameters.announce_initial;
+    ap.max = s->parameters.announce_max;
+    ap.rounds = s->parameters.announce_rounds;
+    ap.step = s->parameters.announce_step;
+
+    return &ap;
+}
+
+MigrationParameters *qmp_query_migrate_parameters(Error **errp)
+{
+    MigrationParameters *params;
+    MigrationState *s = migrate_get_current();
+
+    /* TODO use QAPI_CLONE() instead of duplicating it inline */
+    params = g_malloc0(sizeof(*params));
+    params->has_compress_level = true;
+    params->compress_level = s->parameters.compress_level;
+    params->has_compress_threads = true;
+    params->compress_threads = s->parameters.compress_threads;
+    params->has_compress_wait_thread = true;
+    params->compress_wait_thread = s->parameters.compress_wait_thread;
+    params->has_decompress_threads = true;
+    params->decompress_threads = s->parameters.decompress_threads;
+    params->has_throttle_trigger_threshold = true;
+    params->throttle_trigger_threshold = s->parameters.throttle_trigger_threshold;
+    params->has_cpu_throttle_initial = true;
+    params->cpu_throttle_initial = s->parameters.cpu_throttle_initial;
+    params->has_cpu_throttle_increment = true;
+    params->cpu_throttle_increment = s->parameters.cpu_throttle_increment;
+    params->has_cpu_throttle_tailslow = true;
+    params->cpu_throttle_tailslow = s->parameters.cpu_throttle_tailslow;
+    params->tls_creds = g_strdup(s->parameters.tls_creds);
+    params->tls_hostname = g_strdup(s->parameters.tls_hostname);
+    params->tls_authz = g_strdup(s->parameters.tls_authz ?
+                                 s->parameters.tls_authz : "");
+    params->has_max_bandwidth = true;
+    params->max_bandwidth = s->parameters.max_bandwidth;
+    params->has_downtime_limit = true;
+    params->downtime_limit = s->parameters.downtime_limit;
+    params->has_x_checkpoint_delay = true;
+    params->x_checkpoint_delay = s->parameters.x_checkpoint_delay;
+    params->has_block_incremental = true;
+    params->block_incremental = s->parameters.block_incremental;
+    params->has_multifd_channels = true;
+    params->multifd_channels = s->parameters.multifd_channels;
+    params->has_multifd_compression = true;
+    params->multifd_compression = s->parameters.multifd_compression;
+    params->has_multifd_zlib_level = true;
+    params->multifd_zlib_level = s->parameters.multifd_zlib_level;
+    params->has_multifd_zstd_level = true;
+    params->multifd_zstd_level = s->parameters.multifd_zstd_level;
+    params->has_xbzrle_cache_size = true;
+    params->xbzrle_cache_size = s->parameters.xbzrle_cache_size;
+    params->has_max_postcopy_bandwidth = true;
+    params->max_postcopy_bandwidth = s->parameters.max_postcopy_bandwidth;
+    params->has_max_cpu_throttle = true;
+    params->max_cpu_throttle = s->parameters.max_cpu_throttle;
+    params->has_announce_initial = true;
+    params->announce_initial = s->parameters.announce_initial;
+    params->has_announce_max = true;
+    params->announce_max = s->parameters.announce_max;
+    params->has_announce_rounds = true;
+    params->announce_rounds = s->parameters.announce_rounds;
+    params->has_announce_step = true;
+    params->announce_step = s->parameters.announce_step;
+
+    if (s->parameters.has_block_bitmap_mapping) {
+        params->has_block_bitmap_mapping = true;
+        params->block_bitmap_mapping =
+            QAPI_CLONE(BitmapMigrationNodeAliasList,
+                       s->parameters.block_bitmap_mapping);
+    }
+
+    return params;
+}