12:27 p.m.
When using the mapped-ram migration capability, direct IO is
enabled by setting the "direct-io" migration parameter to
"true" and passing QEMU an additional fd with O_DIRECT set.
Signed-off-by: Jim Fehlig <jfehlig(a)suse.com>
---
src/qemu/qemu_migration.c | 11 ++++++-----
src/qemu/qemu_process.c | 27 +++++++++++++++++++++++----
src/qemu/qemu_process.h | 6 ++++--
3 files changed, 33 insertions(+), 11 deletions(-)
diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index a5a80230b2..d0cbcce044 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -3063,7 +3063,8 @@ qemuMigrationDstPrepareCleanup(virQEMUDriver *driver,
}
static qemuProcessIncomingDef *
-qemuMigrationDstPrepare(virDomainObj *vm,
+qemuMigrationDstPrepare(virQEMUDriver *driver,
+ virDomainObj *vm,
bool tunnel,
const char *protocol,
const char *listenAddress,
@@ -3123,9 +3124,9 @@ qemuMigrationDstPrepare(virDomainObj *vm,
migrateFrom = g_strdup_printf(incFormat, protocol, listenAddress, port);
}
- return qemuProcessIncomingDefNew(vm, listenAddress,
+ return qemuProcessIncomingDefNew(driver, vm, listenAddress,
migrateFrom, fd,
- NULL, NULL);
+ NULL, NULL, NULL);
}
@@ -3265,7 +3266,7 @@ qemuMigrationDstPrepareActive(virQEMUDriver *driver,
goto error;
stopProcess = true;
- if (!(incoming = qemuMigrationDstPrepare(vm, tunnel, protocol,
+ if (!(incoming = qemuMigrationDstPrepare(driver, vm, tunnel, protocol,
listenAddress, port,
&dataFD[0])))
goto error;
@@ -3637,7 +3638,7 @@ qemuMigrationDstPrepareResume(virQEMUDriver *driver,
priv->origname = g_strdup(origname);
- if (!(incoming = qemuMigrationDstPrepare(vm, false, protocol,
+ if (!(incoming = qemuMigrationDstPrepare(driver, vm, false, protocol,
listenAddress, port, NULL)))
goto cleanup;
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 94e7e90d28..f51378aeba 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -4837,13 +4837,16 @@ qemuProcessIncomingDefFree(qemuProcessIncomingDef *inc)
* qemuProcessIncomingDefFree will NOT close it.
*/
qemuProcessIncomingDef *
-qemuProcessIncomingDefNew(virDomainObj *vm,
+qemuProcessIncomingDefNew(virQEMUDriver *driver,
+ virDomainObj *vm,
const char *listenAddress,
const char *migrateFrom,
int *fd,
const char *path,
- virQEMUSaveData *data)
+ virQEMUSaveData *data,
+ qemuMigrationParams *migParams)
{
+ g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
qemuDomainObjPrivate *priv = vm->privateData;
qemuProcessIncomingDef *inc = NULL;
@@ -4856,9 +4859,25 @@ qemuProcessIncomingDefNew(virDomainObj *vm,
if (data && data->header.format == QEMU_SAVE_FORMAT_SPARSE) {
size_t offset = sizeof(virQEMUSaveHeader) + data->header.data_len;
+ bool directio = false;
inc->fdPassMigrate = qemuFDPassNew("libvirt-incoming-migrate",
priv);
- qemuFDPassAddFD(inc->fdPassMigrate, fd, "-fd");
+ /* When using directio with mapped-ram, qemu needs an fd without
+ * O_DIRECT set for reading small bits of unaligned state. */
+ if (qemuMigrationParamsGetBool(migParams, QEMU_MIGRATION_PARAM_DIRECT_IO,
&directio) < 0)
+ goto error;
+
+ if (directio) {
+ VIR_AUTOCLOSE bufferedFd = -1;
+
+ if ((bufferedFd = qemuDomainOpenFile(cfg, NULL, path, O_RDONLY, NULL)) <
0)
+ goto error;
+
+ qemuFDPassAddFD(inc->fdPassMigrate, &bufferedFd,
"-buffered-fd");
+ qemuFDPassAddFD(inc->fdPassMigrate, fd, "direct-io-fd");
+ } else {
+ qemuFDPassAddFD(inc->fdPassMigrate, fd, "-buffered-fd");
+ }
inc->uri = g_strdup_printf("file:%s,offset=%#lx",
qemuFDPassGetPath(inc->fdPassMigrate), offset);
} else {
@@ -8499,7 +8518,7 @@ qemuProcessStartWithMemoryState(virConnectPtr conn,
/* The fd passed to qemuProcessIncomingDefNew is used to create the migration
* URI, so it must be called after starting the decompression program.
*/
- incoming = qemuProcessIncomingDefNew(vm, NULL, "stdio", fd, path, data);
+ incoming = qemuProcessIncomingDefNew(driver, vm, NULL, "stdio", fd, path,
data, migParams);
if (!incoming)
return -1;
diff --git a/src/qemu/qemu_process.h b/src/qemu/qemu_process.h
index c51335ad7a..8f7b3f24c4 100644
--- a/src/qemu/qemu_process.h
+++ b/src/qemu/qemu_process.h
@@ -57,12 +57,14 @@ struct _qemuProcessIncomingDef {
const char *path; /* path associated with fd */
};
-qemuProcessIncomingDef *qemuProcessIncomingDefNew(virDomainObj *vm,
+qemuProcessIncomingDef *qemuProcessIncomingDefNew(virQEMUDriver *driver,
+ virDomainObj *vm,
const char *listenAddress,
const char *migrateFrom,
int *fd,
const char *path,
- virQEMUSaveData *data);
+ virQEMUSaveData *data,
+ qemuMigrationParams *migParams);
void qemuProcessIncomingDefFree(qemuProcessIncomingDef *inc);
--
2.43.0