[Qemu-devel] [PATCH v14 2/3] migration: Create socket-address parameter

[Juan Quintela <quintela@redhat.com>]

It will be used to store the uri parameters. We want this only for
tcp, so we don't set it for other uris.  We need it to know what port
is migration running.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

--

This used to be uri parameter, but it has so many troubles to
reproduce that it don't just make sense.

This used to be a port parameter.  I was asked to move to
SocketAddress, done.
I also merged the setting of the migration tcp port in this one
because now I need to free the address, and this makes it easier.
This used to be x-socket-address with a single direction, now it is a
list of addresses.
Move SocketAddress_to_str here.  I used to try to generalize the one
in chardev/char-socket.c, but it is not worth it.

Free string (eric)
Handle VSOCK address nicely (not that migration can use them yet).
Remove useless breaks (dave)
rename socket_address to socket_address_list to avoid confusion
Update to 4.0 (eric)
Put a comment indicating that there is a problem on the qapi
generator (markus).
---
 hmp.c                 | 33 +++++++++++++++++++++++++++++++++
 migration/migration.c | 24 ++++++++++++++++++++++++
 migration/migration.h |  4 ++++
 migration/socket.c    | 11 +++++++++++
 qapi/migration.json   |  6 +++++-
 qapi/sockets.json     | 18 ++++++++++++++++++
 6 files changed, 95 insertions(+), 1 deletion(-)

diff --git a/hmp.c b/hmp.c
index 1e006eeb49..8e283153b5 100644
--- a/hmp.c
+++ b/hmp.c
@@ -166,6 +166,27 @@ void hmp_info_mice(Monitor *mon, const QDict *qdict)
     qapi_free_MouseInfoList(mice_list);
 }
 
+static char *SocketAddress_to_str(SocketAddress *addr)
+{
+    switch (addr->type) {
+    case SOCKET_ADDRESS_TYPE_INET:
+        return g_strdup_printf("tcp:%s:%s",
+                               addr->u.inet.host,
+                               addr->u.inet.port);
+    case SOCKET_ADDRESS_TYPE_UNIX:
+        return g_strdup_printf("unix:%s",
+                               addr->u.q_unix.path);
+    case SOCKET_ADDRESS_TYPE_FD:
+        return g_strdup_printf("fd:%s", addr->u.fd.str);
+    case SOCKET_ADDRESS_TYPE_VSOCK:
+        return g_strdup_printf("tcp:%s:%s",
+                               addr->u.vsock.cid,
+                               addr->u.vsock.port);
+    default:
+        return g_strdup("unknown address type");
+    }
+}
+
 void hmp_info_migrate(Monitor *mon, const QDict *qdict)
 {
     MigrationInfo *info;
@@ -306,6 +327,18 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
         g_free(str);
         visit_free(v);
     }
+    if (info->has_socket_address) {
+        SocketAddressList *addr;
+
+        monitor_printf(mon, "socket address: [\n");
+
+        for (addr = info->socket_address; addr; addr = addr->next) {
+            char *s = SocketAddress_to_str(addr->value);
+            monitor_printf(mon, "\t%s\n", s);
+            g_free(s);
+        }
+        monitor_printf(mon, "]\n");
+    }
     qapi_free_MigrationInfo(info);
     qapi_free_MigrationCapabilityStatusList(caps);
 }
diff --git a/migration/migration.c b/migration/migration.c
index 37e06b76dc..5ecf0978ac 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -31,6 +31,8 @@
 #include "migration/vmstate.h"
 #include "block/block.h"
 #include "qapi/error.h"
+#include "qapi/clone-visitor.h"
+#include "qapi/qapi-visit-sockets.h"
 #include "qapi/qapi-commands-migration.h"
 #include "qapi/qapi-events-migration.h"
 #include "qapi/qmp/qerror.h"
@@ -197,6 +199,11 @@ void migration_incoming_state_destroy(void)
     }
 
     qemu_event_reset(&mis->main_thread_load_event);
+
+    if (mis->socket_address_list) {
+        qapi_free_SocketAddressList(mis->socket_address_list);
+        mis->socket_address_list = NULL;
+    }
 }
 
 static void migrate_generate_event(int new_state)
@@ -312,6 +319,17 @@ void migration_incoming_enable_colo(void)
     migration_colo_enabled = true;
 }
 
+void migrate_add_address(SocketAddress *address)
+{
+    MigrationIncomingState *mis = migration_incoming_get_current();
+    SocketAddressList *addrs;
+
+    addrs = g_new0(SocketAddressList, 1);
+    addrs->next = mis->socket_address_list;
+    mis->socket_address_list = addrs;
+    addrs->value = QAPI_CLONE(SocketAddress, address);
+}
+
 void qemu_start_incoming_migration(const char *uri, Error **errp)
 {
     const char *p;
@@ -966,6 +984,12 @@ static void fill_destination_migration_info(MigrationInfo *info)
 {
     MigrationIncomingState *mis = migration_incoming_get_current();
 
+    if (mis->socket_address_list) {
+        info->has_socket_address = true;
+        info->socket_address =
+            QAPI_CLONE(SocketAddressList, mis->socket_address_list);
+    }
+
     switch (mis->state) {
     case MIGRATION_STATUS_NONE:
         return;
diff --git a/migration/migration.h b/migration/migration.h
index dcd05d9f87..837709d8a1 100644
--- a/migration/migration.h
+++ b/migration/migration.h
@@ -80,6 +80,9 @@ struct MigrationIncomingState {
     bool postcopy_recover_triggered;
     QemuSemaphore postcopy_pause_sem_dst;
     QemuSemaphore postcopy_pause_sem_fault;
+
+    /* List of listening socket addresses  */
+    SocketAddressList *socket_address_list;
 };
 
 MigrationIncomingState *migration_incoming_get_current(void);
@@ -300,6 +303,7 @@ void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);
 
 void dirty_bitmap_mig_before_vm_start(void);
 void init_dirty_bitmap_incoming_migration(void);
+void migrate_add_address(SocketAddress *address);
 
 #define qemu_ram_foreach_block \
   #warning "Use qemu_ram_foreach_block_migratable in migration code"
diff --git a/migration/socket.c b/migration/socket.c
index f4c8174400..239527fb1f 100644
--- a/migration/socket.c
+++ b/migration/socket.c
@@ -15,6 +15,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/cutils.h"
 
 #include "qemu-common.h"
 #include "qemu/error-report.h"
@@ -177,6 +178,7 @@ static void socket_start_incoming_migration(SocketAddress *saddr,
                                             Error **errp)
 {
     QIONetListener *listener = qio_net_listener_new();
+    size_t i;
 
     qio_net_listener_set_name(listener, "migration-socket-listener");
 
@@ -189,6 +191,15 @@ static void socket_start_incoming_migration(SocketAddress *saddr,
                                           socket_accept_incoming_migration,
                                           NULL, NULL,
                                           g_main_context_get_thread_default());
+
+    for (i = 0; i < listener->nsioc; i++)  {
+        SocketAddress *address =
+            qio_channel_socket_get_local_address(listener->sioc[i], errp);
+        if (!address) {
+            return;
+        }
+        migrate_add_address(address);
+    }
 }
 
 void tcp_start_incoming_migration(const char *host_port, Error **errp)
diff --git a/qapi/migration.json b/qapi/migration.json
index 7a795ecc16..b62947791f 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -6,6 +6,7 @@
 ##
 
 { 'include': 'common.json' }
+{ 'include': 'sockets.json' }
 
 ##
 # @MigrationStats:
@@ -199,6 +200,8 @@
 # @compression: migration compression statistics, only returned if compression
 #           feature is on and status is 'active' or 'completed' (Since 3.1)
 #
+# @socket-address: Only used for tcp, to know what the real port is (Since 4.0)
+#
 # Since: 0.14.0
 ##
 { 'struct': 'MigrationInfo',
@@ -213,7 +216,8 @@
            '*error-desc': 'str',
            '*postcopy-blocktime' : 'uint32',
            '*postcopy-vcpu-blocktime': ['uint32'],
-           '*compression': 'CompressionStats'} }
+           '*compression': 'CompressionStats',
+           '*socket-address': ['SocketAddress'] } }
 
 ##
 # @query-migrate:
diff --git a/qapi/sockets.json b/qapi/sockets.json
index fc81d8d5e8..6eeda4a9d6 100644
--- a/qapi/sockets.json
+++ b/qapi/sockets.json
@@ -152,3 +152,21 @@
             'unix': 'UnixSocketAddress',
             'vsock': 'VsockSocketAddress',
             'fd': 'String' } }
+
+##
+# @DummyStruct:
+#
+# Both block-core and migration needs SocketAddressList
+# I am open to comments about how to share it
+#
+# @dummy-list: A dummy list
+#
+# FIXME: This shouldn't be needed, but this struct has two users, and
+# current qapi generator generates it on the 1st place that uses it,
+# so the second user don't see it.  Putting it here it is seen in both
+# sides.
+#
+# Since: 4.0
+##
+{ 'struct': 'DummyStruct',
+  'data': { 'dummy-list': ['SocketAddress'] } }
-- 
2.20.1