Reintroduce migrate-to-exec: support (Charles Duffy)

KVM's live migration support included support for exec: URLs, allowing system
state to be written or received via an arbitrary popen()ed subprocess. This
provides a convenient way to pipe state through a compression algorithm or an
arbitrary network transport on its way to its destination, and a convenient way
to write state to disk; libvirt's qemu driver currently uses migration to exec:
targets for this latter purpose.

This version of the patch refactors now-common code from migrate-tcp.c into
migrate.c. 

Signed-off-by: Charles Duffy <[email protected]>
Signed-off-by: Anthony Liguori <[email protected]>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5694 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/migration.h b/migration.h
index 9947f6a..953ec70 100644
--- a/migration.h
+++ b/migration.h
@@ -29,6 +29,22 @@
     void (*release)(MigrationState *s);
 };
 
+typedef struct FdMigrationState FdMigrationState;
+
+struct FdMigrationState
+{
+    MigrationState mig_state;
+    int64_t bandwidth_limit;
+    QEMUFile *file;
+    int fd;
+    int detach;
+    int state;
+    int (*get_error)(struct FdMigrationState*);
+    int (*close)(struct FdMigrationState*);
+    int (*write)(struct FdMigrationState*, const void *, size_t);
+    void *opaque;
+};
+
 void qemu_start_incoming_migration(const char *uri);
 
 void do_migrate(int detach, const char *uri);
@@ -39,11 +55,44 @@
 
 void do_info_migrate(void);
 
+int exec_start_incoming_migration(const char *host_port);
+
+MigrationState *exec_start_outgoing_migration(const char *host_port,
+					     int64_t bandwidth_limit,
+					     int detach);
+
 int tcp_start_incoming_migration(const char *host_port);
 
 MigrationState *tcp_start_outgoing_migration(const char *host_port,
 					     int64_t bandwidth_limit,
 					     int detach);
 
+void migrate_fd_error(FdMigrationState *s);
+
+void migrate_fd_cleanup(FdMigrationState *s);
+
+void migrate_fd_put_notify(void *opaque);
+
+ssize_t migrate_fd_put_buffer(void *opaque, const void *data, size_t size);
+
+void migrate_fd_connect(FdMigrationState *s);
+
+void migrate_fd_put_ready(void *opaque);
+
+int migrate_fd_get_status(MigrationState *mig_state);
+
+void migrate_fd_cancel(MigrationState *mig_state);
+
+void migrate_fd_release(MigrationState *mig_state);
+
+void migrate_fd_wait_for_unfreeze(void *opaque);
+
+int migrate_fd_close(void *opaque);
+
+static inline FdMigrationState *migrate_to_fms(MigrationState *mig_state)
+{
+    return container_of(mig_state, FdMigrationState, mig_state);
+}
+
 #endif