migration: convert fd socket protocol to use QIOChannel

Convert the fd socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of plain sockets
APIs. It can be unconditionally built because the
QIOChannel APIs it uses will take care to report suitable
error messages if needed.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-16-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>

diff --git a/migration/Makefile.objs b/migration/Makefile.objs
index 422186195e38c63c205cd44bb66891679216a5bb..2e5040c9e0a9d386e48b2439def58c11cefedbb0 100644 (file)
--- a/migration/Makefile.objs
+++ b/migration/Makefile.objs
@@ -1,4 +1,4 @@
-common-obj-y += migration.o socket.o
+common-obj-y += migration.o socket.o fd.o
 common-obj-y += vmstate.o
 common-obj-y += qemu-file.o qemu-file-buf.o qemu-file-unix.o qemu-file-stdio.o
 common-obj-y += qemu-file-channel.o
@@ -6,7 +6,7 @@ common-obj-y += xbzrle.o postcopy-ram.o
 common-obj-y += qjson.o
 
 common-obj-$(CONFIG_RDMA) += rdma.o
-common-obj-$(CONFIG_POSIX) += exec.o fd.o
+common-obj-$(CONFIG_POSIX) += exec.o
 
 common-obj-y += block.o
 

diff --git a/migration/fd.c b/migration/fd.c
index 3d788bb297139656e5c5eb2dcbeebcca458e8b62..60a75b81e05cb2206a18651efe6bc8fc6e12646c 100644 (file)
--- a/migration/fd.c
+++ b/migration/fd.c
@@ -1,10 +1,11 @@
 /*
  * QEMU live migration via generic fd
  *
- * Copyright Red Hat, Inc. 2009
+ * Copyright Red Hat, Inc. 2009-2016
  *
  * Authors:
  *  Chris Lalancette <clalance@redhat.com>
+ *  Daniel P. Berrange <berrange@redhat.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2.  See
  * the COPYING file in the top-level directory.
@@ -16,75 +17,57 @@
 #include "qemu/osdep.h"
 #include "qapi/error.h"
 #include "qemu-common.h"
-#include "qemu/main-loop.h"
-#include "qemu/sockets.h"
 #include "migration/migration.h"
 #include "monitor/monitor.h"
-#include "migration/qemu-file.h"
-#include "block/block.h"
+#include "io/channel-util.h"
+#include "trace.h"
 
-//#define DEBUG_MIGRATION_FD
-
-#ifdef DEBUG_MIGRATION_FD
-#define DPRINTF(fmt, ...) \
-    do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
-    do { } while (0)
-#endif
-
-static bool fd_is_socket(int fd)
-{
-    struct stat stat;
-    int ret = fstat(fd, &stat);
-    if (ret == -1) {
-        /* When in doubt say no */
-        return false;
-    }
-    return S_ISSOCK(stat.st_mode);
-}
 
 void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp)
 {
+    QIOChannel *ioc;
     int fd = monitor_get_fd(cur_mon, fdname, errp);
     if (fd == -1) {
         return;
     }
 
-    if (fd_is_socket(fd)) {
-        s->to_dst_file = qemu_fopen_socket(fd, "wb");
-    } else {
-        s->to_dst_file = qemu_fdopen(fd, "wb");
+    trace_migration_fd_outgoing(fd);
+    ioc = qio_channel_new_fd(fd, errp);
+    if (!ioc) {
+        close(fd);
+        return;
     }
 
-    migrate_fd_connect(s);
+    migration_set_outgoing_channel(s, ioc);
+    object_unref(OBJECT(ioc));
 }
 
-static void fd_accept_incoming_migration(void *opaque)
+static gboolean fd_accept_incoming_migration(QIOChannel *ioc,
+                                             GIOCondition condition,
+                                             gpointer opaque)
 {
-    QEMUFile *f = opaque;
-
-    qemu_set_fd_handler(qemu_get_fd(f), NULL, NULL, NULL);
-    process_incoming_migration(f);
+    migration_set_incoming_channel(migrate_get_current(), ioc);
+    object_unref(OBJECT(ioc));
+    return FALSE; /* unregister */
 }
 
 void fd_start_incoming_migration(const char *infd, Error **errp)
 {
+    QIOChannel *ioc;
     int fd;
-    QEMUFile *f;
-
-    DPRINTF("Attempting to start an incoming migration via fd\n");
 
     fd = strtol(infd, NULL, 0);
-    if (fd_is_socket(fd)) {
-        f = qemu_fopen_socket(fd, "rb");
-    } else {
-        f = qemu_fdopen(fd, "rb");
-    }
-    if(f == NULL) {
-        error_setg_errno(errp, errno, "failed to open the source descriptor");
+    trace_migration_fd_incoming(fd);
+
+    ioc = qio_channel_new_fd(fd, errp);
+    if (!ioc) {
+        close(fd);
         return;
     }
 
-    qemu_set_fd_handler(fd, fd_accept_incoming_migration, NULL, f);
+    qio_channel_add_watch(ioc,
+                          G_IO_IN,
+                          fd_accept_incoming_migration,
+                          NULL,
+                          NULL);
 }

diff --git a/migration/migration.c b/migration/migration.c
index a38da3a1533253235fa069472dc01d0da6f95980..8decc7d17813a8ace714db8b8e1c2481e606d66d 100644 (file)
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -317,10 +317,8 @@ void qemu_start_incoming_migration(const char *uri, Error **errp)
 #endif
     } else if (strstart(uri, "unix:", &p)) {
         unix_start_incoming_migration(p, errp);
-#if !defined(WIN32)
     } else if (strstart(uri, "fd:", &p)) {
         fd_start_incoming_migration(p, errp);
-#endif
     } else {
         error_setg(errp, "unknown migration protocol: %s", uri);
     }
@@ -1077,10 +1075,8 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
 #endif
     } else if (strstart(uri, "unix:", &p)) {
         unix_start_outgoing_migration(s, p, &local_err);
-#if !defined(WIN32)
     } else if (strstart(uri, "fd:", &p)) {
         fd_start_outgoing_migration(s, p, &local_err);
-#endif
     } else {
         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "uri",
                    "a valid migration protocol");

diff --git a/trace-events b/trace-events
index 62f634d0e0114b4d7fe05a5d6db5bfc29aefd89c..e9945e7964f7451fdbeefd4b96135bb0d69ccf7c 100644 (file)
--- a/trace-events
+++ b/trace-events
@@ -1595,6 +1595,10 @@ postcopy_ram_incoming_cleanup_entry(void) ""
 postcopy_ram_incoming_cleanup_exit(void) ""
 postcopy_ram_incoming_cleanup_join(void) ""
 
+# migration/fd.c
+migration_fd_outgoing(int fd) "fd=%d"
+migration_fd_incoming(int fd) "fd=%d"
+
 # migration/socket.c
 migration_socket_incoming_accepted(void) ""
 migration_socket_outgoing_connected(void) ""