block migration: Allow compile time disable

Many users now prefer to use drive_mirror over NBD as an
alternative to the older migrate -b option; drive_mirror is
more complex to setup but gives you more options (e.g. only
migrating some of the disks if some of them are shared).

Allow the large chunk of block migration code to be compiled
out for those who don't use it.

Based on a downstream-patch we've had for a while by Jeff Cody.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

--

- When compiled out, allow seting block only with false value (eric)
This commit is contained in:
Dr. David Alan Gilbert 2017-05-15 15:05:29 +01:00 committed by Juan Quintela
parent a0762d9e34
commit ed1701c6a5
4 changed files with 49 additions and 2 deletions

11
configure vendored
View file

@ -316,6 +316,7 @@ vte=""
virglrenderer=""
tpm="yes"
libssh2=""
live_block_migration="yes"
numa=""
tcmalloc="no"
jemalloc="no"
@ -1169,6 +1170,10 @@ for opt do
;;
--enable-libssh2) libssh2="yes"
;;
--disable-live-block-migration) live_block_migration="no"
;;
--enable-live-block-migration) live_block_migration="yes"
;;
--disable-numa) numa="no"
;;
--enable-numa) numa="yes"
@ -1401,6 +1406,7 @@ disabled with --disable-FEATURE, default is enabled if available:
libnfs nfs support
smartcard smartcard support (libcacard)
libusb libusb (for usb passthrough)
live-block-migration Block migration in the main migration stream
usb-redir usb network redirection support
lzo support of lzo compression library
snappy support of snappy compression library
@ -5216,6 +5222,7 @@ echo "TPM support $tpm"
echo "libssh2 support $libssh2"
echo "TPM passthrough $tpm_passthrough"
echo "QOM debugging $qom_cast_debug"
echo "Live block migration $live_block_migration"
echo "lzo support $lzo"
echo "snappy support $snappy"
echo "bzip2 support $bzip2"
@ -5782,6 +5789,10 @@ if test "$libssh2" = "yes" ; then
echo "LIBSSH2_LIBS=$libssh2_libs" >> $config_host_mak
fi
if test "$live_block_migration" = "yes" ; then
echo "CONFIG_LIVE_BLOCK_MIGRATION=y" >> $config_host_mak
fi
# USB host support
if test "$libusb" = "yes"; then
echo "HOST_USB=libusb legacy" >> $config_host_mak

View file

@ -14,12 +14,34 @@
#ifndef MIGRATION_BLOCK_H
#define MIGRATION_BLOCK_H
#ifdef CONFIG_LIVE_BLOCK_MIGRATION
void blk_mig_init(void);
int blk_mig_active(void);
uint64_t blk_mig_bytes_transferred(void);
uint64_t blk_mig_bytes_remaining(void);
uint64_t blk_mig_bytes_total(void);
void migrate_set_block_enabled(bool value, Error **errp);
#else
static inline void blk_mig_init(void) { }
static inline int blk_mig_active(void)
{
return false;
}
static inline uint64_t blk_mig_bytes_transferred(void)
{
return 0;
}
static inline uint64_t blk_mig_bytes_remaining(void)
{
return 0;
}
static inline uint64_t blk_mig_bytes_total(void)
{
return 0;
}
#endif /* CONFIG_LIVE_BLOCK_MIGRATION */
void migrate_set_block_enabled(bool value, Error **errp);
#endif /* MIGRATION_BLOCK_H */

View file

@ -9,5 +9,5 @@ common-obj-y += qjson.o
common-obj-$(CONFIG_RDMA) += rdma.o
common-obj-y += block.o
common-obj-$(CONFIG_LIVE_BLOCK_MIGRATION) += block.o

View file

@ -547,6 +547,11 @@ MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp)
caps = NULL; /* silence compiler warning */
for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
#ifndef CONFIG_LIVE_BLOCK_MIGRATION
if (i == MIGRATION_CAPABILITY_BLOCK) {
continue;
}
#endif
if (i == MIGRATION_CAPABILITY_X_COLO && !colo_supported()) {
continue;
}
@ -763,6 +768,15 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
}
for (cap = params; cap; cap = cap->next) {
#ifndef CONFIG_LIVE_BLOCK_MIGRATION
if (cap->value->capability == MIGRATION_CAPABILITY_BLOCK
&& cap->value->state) {
error_setg(errp, "QEMU compiled without old-style (blk/-b, inc/-i) "
"block migration");
error_append_hint(errp, "Use drive_mirror+NBD instead.\n");
continue;
}
#endif
if (cap->value->capability == MIGRATION_CAPABILITY_X_COLO) {
if (!colo_supported()) {
error_setg(errp, "COLO is not currently supported, please"