qemu: Avoid assigning unavailable migration ports

https://bugzilla.redhat.com/show_bug.cgi?id=1019053

When we migrate vms concurrently, there's a chance that libvirtd on
destination assigns the same port for different migrations, which will
lead to migration failure during prepare phase on destination. So we use
virPortAllocator here to solve the problem.

Signed-off-by: Wang Yufei <james.wangyufei@huawei.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
(cherry picked from commit 0196845d3abd0d914cf11f7ad6c19df8b47c32ed)

Conflicts:
  missing support for changing the migration listen address
	src/qemu/qemu_migration.c

diff --git a/src/qemu/qemu_command.h b/src/qemu/qemu_command.h
index 2e2acfb326ef2e9e06bdd89fbaa6c4cb395366e4..3277ba4a8e98f7ab956efbcf4192f49e3ad49c83 100644 (file)
--- a/src/qemu/qemu_command.h
+++ b/src/qemu/qemu_command.h
@@ -51,6 +51,9 @@
 # define QEMU_WEBSOCKET_PORT_MIN  5700
 # define QEMU_WEBSOCKET_PORT_MAX  65535
 
+# define QEMU_MIGRATION_PORT_MIN 49152
+# define QEMU_MIGRATION_PORT_MAX 49215
+
 typedef struct _qemuBuildCommandLineCallbacks qemuBuildCommandLineCallbacks;
 typedef qemuBuildCommandLineCallbacks *qemuBuildCommandLineCallbacksPtr;
 struct _qemuBuildCommandLineCallbacks {

diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
index da29a2aa2aaf6ca2d6eb5c08529d7c1f6e30377d..3176085adcae50194cc66f75b3312b1291560cfa 100644 (file)
--- a/src/qemu/qemu_conf.h
+++ b/src/qemu/qemu_conf.h
@@ -221,6 +221,9 @@ struct _virQEMUDriver {
     /* Immutable pointer, self-locking APIs */
     virPortAllocatorPtr webSocketPorts;
 
+    /* Immutable pointer, self-locking APIs */
+    virPortAllocatorPtr migrationPorts;
+
     /* Immutable pointer, lockless APIs*/
     virSysinfoDefPtr hostsysinfo;
 
@@ -242,9 +245,6 @@ struct _qemuDomainCmdlineDef {
     char **env_value;
 };
 
-/* Port numbers used for KVM migration. */
-# define QEMUD_MIGRATION_FIRST_PORT 49152
-# define QEMUD_MIGRATION_NUM_PORTS 64
 
 
 void qemuDomainCmdlineDefFree(qemuDomainCmdlineDefPtr def);

diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index 21f116c6d3b76ebb479b61eab823a33ae1c5ed5b..04f08a3784dfa315afc8a73f77a3f0b52d6370fb 100644 (file)
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -160,6 +160,7 @@ struct _qemuDomainObjPrivate {
     unsigned long migMaxBandwidth;
     char *origname;
     int nbdPort; /* Port used for migration with NBD */
+    unsigned short migrationPort;
 
     virChrdevsPtr devs;
 

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 2585a16bbc57fe63a01107d1724618f24ae8a088..f22106a94efa176d715d4d4a14e02cb4b70a338a 100644 (file)
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -687,6 +687,11 @@ qemuStateInitialize(bool privileged,
                              cfg->webSocketPortMax)) == NULL)
         goto error;
 
+    if ((qemu_driver->migrationPorts =
+         virPortAllocatorNew(QEMU_MIGRATION_PORT_MIN,
+                             QEMU_MIGRATION_PORT_MAX)) == NULL)
+        goto error;
+
     if (qemuSecurityInit(qemu_driver) < 0)
         goto error;
 
@@ -992,6 +997,7 @@ qemuStateCleanup(void) {
     virObjectUnref(qemu_driver->domains);
     virObjectUnref(qemu_driver->remotePorts);
     virObjectUnref(qemu_driver->webSocketPorts);
+    virObjectUnref(qemu_driver->migrationPorts);
 
     virObjectUnref(qemu_driver->xmlopt);
 

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index c0b17c3d5193d5b3b19e3df571477fc236bda73e..d83293dcfefd27169245593809cbb6dbdb27838d 100644 (file)
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -2151,6 +2151,9 @@ qemuMigrationPrepareCleanup(virQEMUDriverPtr driver,
               qemuDomainJobTypeToString(priv->job.active),
               qemuDomainAsyncJobTypeToString(priv->job.asyncJob));
 
+    virPortAllocatorRelease(driver->migrationPorts, priv->migrationPort);
+    priv->migrationPort = 0;
+
     if (!qemuMigrationJobIsActive(vm, QEMU_ASYNC_JOB_MIGRATION_IN))
         return;
     qemuDomainObjDiscardAsyncJob(driver, vm);
@@ -2166,7 +2169,8 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
                         virDomainDefPtr *def,
                         const char *origname,
                         virStreamPtr st,
-                        unsigned int port,
+                        unsigned short port,
+                        bool autoPort,
                         unsigned long flags)
 {
     virDomainObjPtr vm = NULL;
@@ -2412,6 +2416,8 @@ done:
         goto cleanup;
     }
 
+    if (autoPort)
+        priv->migrationPort = port;
     ret = 0;
 
 cleanup:
@@ -2479,7 +2485,7 @@ qemuMigrationPrepareTunnel(virQEMUDriverPtr driver,
 
     ret = qemuMigrationPrepareAny(driver, dconn, cookiein, cookieinlen,
                                   cookieout, cookieoutlen, def, origname,
-                                  st, 0, flags);
+                                  st, 0, false, flags);
     return ret;
 }
 
@@ -2497,8 +2503,8 @@ qemuMigrationPrepareDirect(virQEMUDriverPtr driver,
                            const char *origname,
                            unsigned long flags)
 {
-    static int port = 0;
-    int this_port;
+    unsigned short port = 0;
+    bool autoPort = true;
     char *hostname = NULL;
     const char *p;
     char *uri_str = NULL;
@@ -2525,10 +2531,15 @@ qemuMigrationPrepareDirect(virQEMUDriverPtr driver,
      * to be a correct hostname which refers to the target machine).
      */
     if (uri_in == NULL) {
-        this_port = QEMUD_MIGRATION_FIRST_PORT + port++;
-        if (port == QEMUD_MIGRATION_NUM_PORTS) port = 0;
+        if (virPortAllocatorAcquire(driver->migrationPorts, &port) < 0) {
+            goto cleanup;
+        } else if (!port) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                           _("No migration port available within the "
+                             "configured range"));
+            goto cleanup;
+        }
 
-        /* Get hostname */
         if ((hostname = virGetHostname()) == NULL)
             goto cleanup;
 
@@ -2545,7 +2556,7 @@ qemuMigrationPrepareDirect(virQEMUDriverPtr driver,
          * new targets accept both syntaxes though.
          */
         /* Caller frees */
-        if (virAsprintf(uri_out, "tcp:%s:%d", hostname, this_port) < 0)
+        if (virAsprintf(uri_out, "tcp:%s:%d", hostname, port) < 0)
             goto cleanup;
     } else {
         /* Check the URI starts with "tcp:".  We will escape the
@@ -2581,17 +2592,22 @@ qemuMigrationPrepareDirect(virQEMUDriverPtr driver,
         }
 
         if (uri->port == 0) {
-            /* Generate a port */
-            this_port = QEMUD_MIGRATION_FIRST_PORT + port++;
-            if (port == QEMUD_MIGRATION_NUM_PORTS)
-                port = 0;
+            if (virPortAllocatorAcquire(driver->migrationPorts, &port) < 0) {
+                goto cleanup;
+            } else if (!port) {
+                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                               _("No migration port available within the "
+                                 "configured range"));
+                goto cleanup;
+            }
 
             /* Caller frees */
-            if (virAsprintf(uri_out, "%s:%d", uri_in, this_port) < 0)
+            if (virAsprintf(uri_out, "%s:%d", uri_in, port) < 0)
                 goto cleanup;
 
         } else {
-            this_port = uri->port;
+            port = uri->port;
+            autoPort = false;
         }
     }
 
@@ -2600,12 +2616,15 @@ qemuMigrationPrepareDirect(virQEMUDriverPtr driver,
 
     ret = qemuMigrationPrepareAny(driver, dconn, cookiein, cookieinlen,
                                   cookieout, cookieoutlen, def, origname,
-                                  NULL, this_port, flags);
+                                  NULL, port, autoPort, flags);
 cleanup:
     virURIFree(uri);
     VIR_FREE(hostname);
-    if (ret != 0)
+    if (ret != 0) {
         VIR_FREE(*uri_out);
+        if (autoPort)
+            virPortAllocatorRelease(driver->migrationPorts, port);
+    }
     return ret;
 }
 
@@ -4374,6 +4393,8 @@ qemuMigrationFinish(virQEMUDriverPtr driver,
         }
 
         qemuMigrationStopNBDServer(driver, vm, mig);
+        virPortAllocatorRelease(driver->migrationPorts, priv->migrationPort);
+        priv->migrationPort = 0;
 
         if (flags & VIR_MIGRATE_PERSIST_DEST) {
             virDomainDefPtr vmdef;