[PATCH v4 8/8] migration: Introduced MigrateChannelList struct to migration code flow.

[Het Gala]

Integrated MigrateChannelList with all transport backends (socket, exec
and rdma) for both source and destination migration code flow.

Suggested-by: Aravind Retnakaran <aravind.retnakaran@nutanix.com>
Signed-off-by: Het Gala <het.gala@nutanix.com>
---
 migration/migration.c | 95 +++++++++++++++++++++++++++----------------
 migration/socket.c    |  5 ++-
 2 files changed, 64 insertions(+), 36 deletions(-)

diff --git a/migration/migration.c b/migration/migration.c
index de058643a6..a37eba29e3 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -410,10 +410,11 @@ void migrate_add_address(SocketAddress *address)
 }
 
 static bool migrate_uri_parse(const char *uri,
-                              MigrateAddress **channel,
+                              MigrateChannel **channel,
                               Error **errp)
 {
     Error *local_err = NULL;
+    MigrateChannel *val = g_new0(MigrateChannel, 1);
     MigrateAddress *addrs = g_new0(MigrateAddress, 1);
     SocketAddress *saddr;
     InetSocketAddress *isock = &addrs->u.rdma;
@@ -441,6 +442,7 @@ static bool migrate_uri_parse(const char *uri,
     }
 
     if (local_err) {
+        qapi_free_MigrateChannel(val);
         qapi_free_MigrateAddress(addrs);
         qapi_free_SocketAddress(saddr);
         qapi_free_InetSocketAddress(isock);
@@ -448,7 +450,9 @@ static bool migrate_uri_parse(const char *uri,
         return false;
     }
 
-    *channel = addrs;
+    val->channeltype = MIGRATE_CHANNEL_TYPE_MAIN;
+    val->addr = addrs;
+    *channel = val;
     return true;
 }
 
@@ -457,8 +461,9 @@ static void qemu_start_incoming_migration(const char *uri, 
bool has_channels,
                                           Error **errp)
 {
     Error *local_err = NULL;
-    MigrateAddress *channel = g_new0(MigrateAddress, 1);
+    MigrateAddress *addrs;
     SocketAddress *saddr;
+    MigrateChannel *channel = NULL;
 
     /*
      * Having preliminary checks for uri and channel
@@ -467,22 +472,30 @@ static void qemu_start_incoming_migration(const char 
*uri, bool has_channels,
         error_setg(errp, "'uri' and 'channels' arguments are mutually "
                    "exclusive; exactly one of the two should be present in "
                    "'migrate-incoming' qmp command ");
-        return;
-    }
-
-    /* URI is not suitable for migration? */
-    if (!migration_channels_and_uri_compatible(uri, errp)) {
         goto out;
-    }
+    } else if (channels) {
+        /* To verify that Migrate channel list has only item */
+        if (channels->next) {
+            error_setg(errp, "Channel list has more than one entries");
+            goto out;
+        }
+        channel = channels->value;
+    } else {
+        /* URI is not suitable for migration? */
+        if (!migration_channels_and_uri_compatible(uri, errp)) {
+            goto out;
+        }
 
-    if (uri && !migrate_uri_parse(uri, &channel, errp)) {
-        error_setg(errp, "Error parsing uri");
-        goto out;
+        if (uri && !migrate_uri_parse(uri, &channel, errp)) {
+            error_setg(errp, "Error parsing uri");
+            goto out;
+        }
     }
 
-    saddr = &channel->u.socket;
+    addrs = channel->addr;
+    saddr = &channel->addr->u.socket;
     qapi_event_send_migration(MIGRATION_STATUS_SETUP);
-    if (channel->transport == MIGRATE_TRANSPORT_SOCKET) {
+    if (addrs->transport == MIGRATE_TRANSPORT_SOCKET) {
         if (saddr->type == SOCKET_ADDRESS_TYPE_INET ||
             saddr->type == SOCKET_ADDRESS_TYPE_UNIX ||
             saddr->type == SOCKET_ADDRESS_TYPE_VSOCK) {
@@ -491,23 +504,25 @@ static void qemu_start_incoming_migration(const char 
*uri, bool has_channels,
             fd_start_incoming_migration(saddr->u.fd.str, &local_err);
         }
 #ifdef CONFIG_RDMA
-    } else if (channel->transport == MIGRATE_TRANSPORT_RDMA) {
-        rdma_start_incoming_migration(&channel->u.rdma, &local_err);
+    } else if (addrs->transport == MIGRATE_TRANSPORT_RDMA) {
+        rdma_start_incoming_migration(&addrs->u.rdma, &local_err);
 #endif
-    } else if (channel->transport == MIGRATE_TRANSPORT_EXEC) {
-        exec_start_incoming_migration(channel->u.exec.args, &local_err);
+    } else if (addrs->transport == MIGRATE_TRANSPORT_EXEC) {
+        exec_start_incoming_migration(addrs->u.exec.args, &local_err);
     } else {
         error_setg(errp, "unknown migration protocol: %s", uri);
     }
 
     if (local_err) {
+        qapi_free_MigrateAddress(addrs);
         qapi_free_SocketAddress(saddr);
         error_propagate(errp, local_err);
         return;
     }
 
 out:
-    qapi_free_MigrateAddress(channel);
+    qapi_free_MigrateChannel(channel);
+    return;
 }
 
 static void process_incoming_migration_bh(void *opaque)
@@ -1714,8 +1729,9 @@ void qmp_migrate(const char *uri, bool has_channels,
 {
     Error *local_err = NULL;
     MigrationState *s = migrate_get_current();
-    MigrateAddress *channel = g_new0(MigrateAddress, 1);
+    MigrateAddress *addrs;
     SocketAddress *saddr;
+    MigrateChannel *channel = NULL;
 
     /*
      * Having preliminary checks for uri and channel
@@ -1724,17 +1740,24 @@ void qmp_migrate(const char *uri, bool has_channels,
         error_setg(errp, "'uri' and 'channels' arguments are mutually "
                    "exclusive; exactly one of the two should be present in "
                    "'migrate' qmp command ");
-        return;
-    }
-
-    /* URI is not suitable for migration? */
-    if (!migration_channels_and_uri_compatible(uri, errp)) {
         goto out;
-    }
+    } else if (channels) {
+        /* To verify that Migrate channel list has only item */
+        if (channels->next) {
+            error_setg(errp, "Channel list has more than one entries");
+            goto out;
+        }
+        channel = channels->value;
+    } else {
+        /* URI is not suitable for migration? */
+        if (!migration_channels_and_uri_compatible(uri, errp)) {
+            goto out;
+        }
 
-    if (!migrate_uri_parse(uri, &channel, &local_err)) {
-        error_setg(errp, "Error parsing uri");
-        goto out;
+        if (!migrate_uri_parse(uri, &channel, &local_err)) {
+            error_setg(errp, "Error parsing uri");
+            goto out;
+        }
     }
 
     if (!migrate_prepare(s, has_blk && blk, has_inc && inc,
@@ -1749,8 +1772,9 @@ void qmp_migrate(const char *uri, bool has_channels,
         }
     }
 
-    saddr = &channel->u.socket;
-    if (channel->transport == MIGRATE_TRANSPORT_SOCKET) {
+    addrs = channel->addr;
+    saddr = &channel->addr->u.socket;
+    if (addrs->transport == MIGRATE_TRANSPORT_SOCKET) {
         if (saddr->type == SOCKET_ADDRESS_TYPE_INET ||
             saddr->type == SOCKET_ADDRESS_TYPE_UNIX ||
             saddr->type == SOCKET_ADDRESS_TYPE_VSOCK) {
@@ -1759,11 +1783,11 @@ void qmp_migrate(const char *uri, bool has_channels,
             fd_start_outgoing_migration(s, saddr->u.fd.str, &local_err);
         }
 #ifdef CONFIG_RDMA
-    } else if (channel->transport == MIGRATE_TRANSPORT_RDMA) {
-        rdma_start_outgoing_migration(s, &channel->u.rdma, &local_err);
+    } else if (addrs->transport == MIGRATE_TRANSPORT_RDMA) {
+        rdma_start_outgoing_migration(s, &addrs->u.rdma, &local_err);
 #endif
-    } else if (channel->transport == MIGRATE_TRANSPORT_EXEC) {
-        exec_start_outgoing_migration(s, channel->u.exec.args, &local_err);
+    } else if (addrs->transport == MIGRATE_TRANSPORT_EXEC) {
+        exec_start_outgoing_migration(s, addrs->u.exec.args, &local_err);
     } else {
         if (!(has_resume && resume)) {
             yank_unregister_instance(MIGRATION_YANK_INSTANCE);
@@ -1780,6 +1804,7 @@ void qmp_migrate(const char *uri, bool has_channels,
         if (!(has_resume && resume)) {
             yank_unregister_instance(MIGRATION_YANK_INSTANCE);
         }
+        qapi_free_MigrateAddress(addrs);
         qapi_free_SocketAddress(saddr);
         migrate_fd_error(s, local_err);
         error_propagate(errp, local_err);
diff --git a/migration/socket.c b/migration/socket.c
index 8e7430b266..98e3ea1514 100644
--- a/migration/socket.c
+++ b/migration/socket.c
@@ -28,6 +28,8 @@
 #include "trace.h"
 #include "postcopy-ram.h"
 #include "options.h"
+#include "qapi/clone-visitor.h"
+#include "qapi/qapi-visit-sockets.h"
 
 struct SocketOutgoingArgs {
     SocketAddress *saddr;
@@ -114,12 +116,13 @@ void socket_start_outgoing_migration(MigrationState *s,
 {
     QIOChannelSocket *sioc = qio_channel_socket_new();
     struct SocketConnectData *data = g_new0(struct SocketConnectData, 1);
+    SocketAddress *addr = QAPI_CLONE(SocketAddress, saddr);
 
     data->s = s;
 
     /* in case previous migration leaked it */
     qapi_free_SocketAddress(outgoing_args.saddr);
-    outgoing_args.saddr = saddr;
+    outgoing_args.saddr = addr;
 
     if (saddr->type == SOCKET_ADDRESS_TYPE_INET) {
         data->hostname = g_strdup(saddr->u.inet.host);
-- 
2.22.3