[PATCH v2.1 02/11] Introduce NBD migration cookie

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This migration cookie is meant for two purposes. The first is to be sent
in begin phase from source to destination to let it know we support new
implementation of VIR_MIGRATE_NON_SHARED_{DISK,INC} so destination can
start NBD server. Then, the second purpose is, destination can let us
know, on which port is NBD server running.
---
 src/qemu/qemu_migration.c | 145 +++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 124 insertions(+), 21 deletions(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 5dcbb07..7d61ec7 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -72,6 +72,7 @@ enum qemuMigrationCookieFlags {
     QEMU_MIGRATION_COOKIE_FLAG_LOCKSTATE,
     QEMU_MIGRATION_COOKIE_FLAG_PERSISTENT,
     QEMU_MIGRATION_COOKIE_FLAG_NETWORK,
+    QEMU_MIGRATION_COOKIE_FLAG_NBD,
 
     QEMU_MIGRATION_COOKIE_FLAG_LAST
 };
@@ -79,13 +80,18 @@ enum qemuMigrationCookieFlags {
 VIR_ENUM_DECL(qemuMigrationCookieFlag);
 VIR_ENUM_IMPL(qemuMigrationCookieFlag,
               QEMU_MIGRATION_COOKIE_FLAG_LAST,
-              "graphics", "lockstate", "persistent", "network");
+              "graphics",
+              "lockstate",
+              "persistent",
+              "network",
+              "nbd");
 
 enum qemuMigrationCookieFeatures {
     QEMU_MIGRATION_COOKIE_GRAPHICS  = (1 << QEMU_MIGRATION_COOKIE_FLAG_GRAPHICS),
     QEMU_MIGRATION_COOKIE_LOCKSTATE = (1 << QEMU_MIGRATION_COOKIE_FLAG_LOCKSTATE),
     QEMU_MIGRATION_COOKIE_PERSISTENT = (1 << QEMU_MIGRATION_COOKIE_FLAG_PERSISTENT),
     QEMU_MIGRATION_COOKIE_NETWORK = (1 << QEMU_MIGRATION_COOKIE_FLAG_NETWORK),
+    QEMU_MIGRATION_COOKIE_NBD = (1 << QEMU_MIGRATION_COOKIE_FLAG_NBD),
 };
 
 typedef struct _qemuMigrationCookieGraphics qemuMigrationCookieGraphics;
@@ -119,6 +125,17 @@ struct _qemuMigrationCookieNetwork {
     qemuMigrationCookieNetDataPtr net;
 };
 
+typedef struct _qemuMigrationCookieNBD qemuMigrationCookieNBD;
+typedef qemuMigrationCookieNBD *qemuMigrationCookieNBDPtr;
+struct _qemuMigrationCookieNBD {
+    int port; /* on which port does NBD server listen for incoming data.
+                 Zero value has special meaning - it is there just to let
+                 destination know we (the source) do support NBD.
+                 Negative one is meant to be sent when translating from
+                 perform to finish phase to let destination know it's
+                 safe to stop NBD server.*/
+};
+
 typedef struct _qemuMigrationCookie qemuMigrationCookie;
 typedef qemuMigrationCookie *qemuMigrationCookiePtr;
 struct _qemuMigrationCookie {
@@ -147,6 +164,9 @@ struct _qemuMigrationCookie {
 
     /* If (flags & QEMU_MIGRATION_COOKIE_NETWORK) */
     qemuMigrationCookieNetworkPtr network;
+
+    /* If (flags & QEMU_MIGRATION_COOKIE_NBD) */
+    qemuMigrationCookieNBDPtr nbd;
 };
 
 static void qemuMigrationCookieGraphicsFree(qemuMigrationCookieGraphicsPtr grap)
@@ -192,6 +212,7 @@ static void qemuMigrationCookieFree(qemuMigrationCookiePtr mig)
     VIR_FREE(mig->name);
     VIR_FREE(mig->lockState);
     VIR_FREE(mig->lockDriver);
+    VIR_FREE(mig->nbd);
     VIR_FREE(mig);
 }
 
@@ -492,6 +513,24 @@ qemuMigrationCookieAddNetwork(qemuMigrationCookiePtr mig,
 }
 
 
+static int
+qemuMigrationCookieAddNBD(qemuMigrationCookiePtr mig,
+                          int nbdPort)
+{
+    /* It is not a bug if there already is a NBD data */
+    if (!mig->nbd &&
+        VIR_ALLOC(mig->nbd) < 0) {
+        virReportOOMError();
+        return -1;
+    }
+
+    mig->nbd->port = nbdPort;
+    mig->flags |= QEMU_MIGRATION_COOKIE_NBD;
+
+    return 0;
+}
+
+
 static void qemuMigrationCookieGraphicsXMLFormat(virBufferPtr buf,
                                                  qemuMigrationCookieGraphicsPtr grap)
 {
@@ -594,6 +633,13 @@ qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,
     if ((mig->flags & QEMU_MIGRATION_COOKIE_NETWORK) && mig->network)
         qemuMigrationCookieNetworkXMLFormat(buf, mig->network);
 
+    if ((mig->flags & QEMU_MIGRATION_COOKIE_NBD) && mig->nbd) {
+        virBufferAddLit(buf, "  <nbd");
+        if (mig->nbd->port)
+            virBufferAsprintf(buf, " port='%d'", mig->nbd->port);
+        virBufferAddLit(buf, "/>\n");
+    }
+
     virBufferAddLit(buf, "</qemu-migration>\n");
     return 0;
 }
@@ -821,6 +867,12 @@ qemuMigrationCookieXMLParse(qemuMigrationCookiePtr mig,
             goto error;
         }
 
+        /* nbd is optional */
+        if (val == QEMU_MIGRATION_COOKIE_FLAG_NBD) {
+            VIR_FREE(str);
+            continue;
+        }
+
         if ((flags & (1 << val)) == 0) {
             virReportError(VIR_ERR_INTERNAL_ERROR,
                            _("Unsupported migration cookie feature %s"),
@@ -873,6 +925,25 @@ qemuMigrationCookieXMLParse(qemuMigrationCookiePtr mig,
         (!(mig->network = qemuMigrationCookieNetworkXMLParse(ctxt))))
         goto error;
 
+    if (flags & QEMU_MIGRATION_COOKIE_NBD &&
+        virXPathBoolean("count(./nbd) > 0", ctxt)) {
+        char *port;
+
+        if (VIR_ALLOC(mig->nbd) < 0) {
+            virReportOOMError();
+            goto error;
+        }
+
+        port = virXPathString("string(./nbd/@port)", ctxt);
+        if (port &&
+            virStrToLong_i(port, NULL, 10, &mig->nbd->port) < 0) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Malformed nbd port '%s'"),
+                           port);
+            goto error;
+        }
+    }
+
     return 0;
 
 error:
@@ -911,6 +982,7 @@ static int
 qemuMigrationBakeCookie(qemuMigrationCookiePtr mig,
                         virQEMUDriverPtr driver,
                         virDomainObjPtr dom,
+                        int nbdPort,
                         char **cookieout,
                         int *cookieoutlen,
                         unsigned int flags)
@@ -937,6 +1009,10 @@ qemuMigrationBakeCookie(qemuMigrationCookiePtr mig,
         return -1;
     }
 
+    if (flags & QEMU_MIGRATION_COOKIE_NBD &&
+        qemuMigrationCookieAddNBD(mig, nbdPort) < 0)
+        return -1;
+
     if (!(*cookieout = qemuMigrationCookieXMLFormatStr(driver, mig)))
         return -1;
 
@@ -1422,6 +1498,7 @@ char *qemuMigrationBegin(virQEMUDriverPtr driver,
     qemuMigrationCookiePtr mig = NULL;
     virDomainDefPtr def = NULL;
     qemuDomainObjPrivatePtr priv = vm->privateData;
+    unsigned int cookieFlags = QEMU_MIGRATION_COOKIE_LOCKSTATE;
 
     VIR_DEBUG("driver=%p, vm=%p, xmlin=%s, dname=%s,"
               " cookieout=%p, cookieoutlen=%p, flags=%lx",
@@ -1441,12 +1518,21 @@ char *qemuMigrationBegin(virQEMUDriverPtr driver,
     if (!(flags & VIR_MIGRATE_UNSAFE) && !qemuMigrationIsSafe(vm->def))
         goto cleanup;
 
+    if (flags & (VIR_MIGRATE_NON_SHARED_DISK | VIR_MIGRATE_NON_SHARED_INC) &&
+        qemuCapsGet(priv->caps, QEMU_CAPS_NBD_SERVER)) {
+        /* TODO support NBD for TUNNELLED migration */
+        if (flags & VIR_MIGRATE_TUNNELLED)
+            VIR_DEBUG("NBD in tunnelled migration is currently not supported");
+        else
+            cookieFlags |= QEMU_MIGRATION_COOKIE_NBD;
+    }
+
     if (!(mig = qemuMigrationEatCookie(driver, vm, NULL, 0, 0)))
         goto cleanup;
 
-    if (qemuMigrationBakeCookie(mig, driver, vm,
+    if (qemuMigrationBakeCookie(mig, driver, vm, 0,
                                 cookieout, cookieoutlen,
-                                QEMU_MIGRATION_COOKIE_LOCKSTATE) < 0)
+                                cookieFlags) < 0)
         goto cleanup;
 
     if (flags & VIR_MIGRATE_OFFLINE) {
@@ -1543,6 +1629,7 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
     char *origname = NULL;
     char *xmlout = NULL;
     unsigned int cookieFlags;
+    int nbdPort = 0;
 
     if (virTimeMillisNow(&now) < 0)
         return -1;
@@ -1642,7 +1729,8 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
     origname = NULL;
 
     if (!(mig = qemuMigrationEatCookie(driver, vm, cookiein, cookieinlen,
-                                       QEMU_MIGRATION_COOKIE_LOCKSTATE)))
+                                       QEMU_MIGRATION_COOKIE_LOCKSTATE |
+                                       QEMU_MIGRATION_COOKIE_NBD)))
         goto cleanup;
 
     if (qemuMigrationJobStart(driver, vm, QEMU_ASYNC_JOB_MIGRATION_IN) < 0)
@@ -1702,8 +1790,12 @@ done:
     else
         cookieFlags = QEMU_MIGRATION_COOKIE_GRAPHICS;
 
-    if (qemuMigrationBakeCookie(mig, driver, vm, cookieout, cookieoutlen,
-                                cookieFlags) < 0) {
+    /* dummy place holder for real work */
+    nbdPort = 0;
+    cookieFlags |= QEMU_MIGRATION_COOKIE_NBD;
+
+    if (qemuMigrationBakeCookie(mig, driver, vm, nbdPort,
+                                cookieout, cookieoutlen, cookieFlags) < 0) {
         /* We could tear down the whole guest here, but
          * cookie data is (so far) non-critical, so that
          * seems a little harsh. We'll just warn for now.
@@ -2198,6 +2290,7 @@ qemuMigrationRun(virQEMUDriverPtr driver,
     int fd = -1;
     unsigned long migrate_speed = resource ? resource : priv->migMaxBandwidth;
     virErrorPtr orig_err = NULL;
+    unsigned int cookieFlags = QEMU_MIGRATION_COOKIE_GRAPHICS;
 
     VIR_DEBUG("driver=%p, vm=%p, cookiein=%s, cookieinlen=%d, "
               "cookieout=%p, cookieoutlen=%p, flags=%lx, resource=%lu, "
@@ -2206,6 +2299,16 @@ qemuMigrationRun(virQEMUDriverPtr driver,
               cookieout, cookieoutlen, flags, resource,
               spec, spec->destType, spec->fwdType);
 
+    if (flags & VIR_MIGRATE_NON_SHARED_DISK) {
+        migrate_flags |= QEMU_MONITOR_MIGRATE_NON_SHARED_DISK;
+        cookieFlags |= QEMU_MIGRATION_COOKIE_NBD;
+    }
+
+    if (flags & VIR_MIGRATE_NON_SHARED_INC) {
+        migrate_flags |= QEMU_MONITOR_MIGRATE_NON_SHARED_INC;
+        cookieFlags |= QEMU_MIGRATION_COOKIE_NBD;
+    }
+
     if (virLockManagerPluginUsesState(driver->lockManager) &&
         !cookieout) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -2215,9 +2318,12 @@ qemuMigrationRun(virQEMUDriverPtr driver,
         return -1;
     }
 
-    if (!(mig = qemuMigrationEatCookie(driver, vm, cookiein, cookieinlen,
-                                       QEMU_MIGRATION_COOKIE_GRAPHICS)))
+    if (!(mig = qemuMigrationEatCookie(driver, vm, cookiein,
+                                       cookieinlen, cookieFlags))) {
+        cookieFlags &= ~QEMU_MIGRATION_COOKIE_GRAPHICS;
         goto cleanup;
+    }
+    cookieFlags &= ~QEMU_MIGRATION_COOKIE_GRAPHICS;
 
     if (qemuDomainMigrateGraphicsRelocate(driver, vm, mig) < 0)
         VIR_WARN("unable to provide data for graphics client relocation");
@@ -2249,11 +2355,6 @@ qemuMigrationRun(virQEMUDriverPtr driver,
         goto cleanup;
     }
 
-    if (flags & VIR_MIGRATE_NON_SHARED_DISK)
-        migrate_flags |= QEMU_MONITOR_MIGRATE_NON_SHARED_DISK;
-
-    if (flags & VIR_MIGRATE_NON_SHARED_INC)
-        migrate_flags |= QEMU_MONITOR_MIGRATE_NON_SHARED_INC;
 
     /* connect to the destination qemu if needed */
     if (spec->destType == MIGRATION_DEST_CONNECT_HOST &&
@@ -2361,10 +2462,11 @@ cleanup:
         VIR_FORCE_CLOSE(fd);
     }
 
+    cookieFlags |= (QEMU_MIGRATION_COOKIE_PERSISTENT |
+                    QEMU_MIGRATION_COOKIE_NETWORK);
     if (ret == 0 &&
-        qemuMigrationBakeCookie(mig, driver, vm, cookieout, cookieoutlen,
-                                QEMU_MIGRATION_COOKIE_PERSISTENT |
-                                QEMU_MIGRATION_COOKIE_NETWORK) < 0) {
+        qemuMigrationBakeCookie(mig, driver, vm, -1, cookieout,
+                                cookieoutlen, cookieFlags) < 0) {
         VIR_WARN("Unable to encode migration cookie");
     }
 
@@ -3301,7 +3403,7 @@ qemuMigrationFinish(virQEMUDriverPtr driver,
     int newVM = 1;
     qemuMigrationCookiePtr mig = NULL;
     virErrorPtr orig_err = NULL;
-    int cookie_flags = 0;
+    int cookieFlags = 0;
     qemuDomainObjPrivatePtr priv = vm->privateData;
 
     VIR_DEBUG("driver=%p, dconn=%p, vm=%p, cookiein=%s, cookieinlen=%d, "
@@ -3318,12 +3420,12 @@ qemuMigrationFinish(virQEMUDriverPtr driver,
 
     qemuDomainCleanupRemove(vm, qemuMigrationPrepareCleanup);
 
-    cookie_flags = QEMU_MIGRATION_COOKIE_NETWORK;
+    cookieFlags = QEMU_MIGRATION_COOKIE_NETWORK | QEMU_MIGRATION_COOKIE_NBD;
     if (flags & VIR_MIGRATE_PERSIST_DEST)
-        cookie_flags |= QEMU_MIGRATION_COOKIE_PERSISTENT;
+        cookieFlags |= QEMU_MIGRATION_COOKIE_PERSISTENT;
 
     if (!(mig = qemuMigrationEatCookie(driver, vm, cookiein,
-                                       cookieinlen, cookie_flags)))
+                                       cookieinlen, cookieFlags)))
         goto endjob;
 
     /* Did the migration go as planned?  If yes, return the domain
@@ -3470,7 +3572,8 @@ qemuMigrationFinish(virQEMUDriverPtr driver,
                                          VIR_DOMAIN_EVENT_STOPPED_FAILED);
     }
 
-    if (qemuMigrationBakeCookie(mig, driver, vm, cookieout, cookieoutlen, 0) < 0)
+    if (qemuMigrationBakeCookie(mig, driver, vm, 0,
+                                cookieout, cookieoutlen, 0) < 0)
         VIR_WARN("Unable to encode migration cookie");
 
 endjob:
-- 
1.8.0.2

--
libvir-list mailing list
libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list


[Index of Archives]     [Virt Tools]     [Libvirt Users]     [Lib OS Info]     [Fedora Users]     [Fedora Desktop]     [Fedora SELinux]     [Big List of Linux Books]     [Yosemite News]     [KDE Users]     [Fedora Tools]