Re: [libvirt] [PATCH v2 4/4] qemu: Forbid migration with cache != none

On Wed, Feb 22, 2012 at 03:51:11PM +0100, Jiri Denemark wrote: > Migrating domains with disks using cache != none is unsafe unless the > disk images are stored on coherent clustered filesystem. Thus we forbid > migrating such domains unless VIR_MIGRATE_UNSAFE flags is used. > --- > Notes: > Version 2: > - use virStorageFileIsClusterFS > > src/qemu/qemu_driver.c | 3 ++- > src/qemu/qemu_migration.c | 39 +++++++++++++++++++++++++++++++++++---- > src/qemu/qemu_migration.h | 6 ++++-- > 3 files changed, 41 insertions(+), 7 deletions(-) > > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c > index 717bdf1..63a0703 100644 > --- a/src/qemu/qemu_driver.c > +++ b/src/qemu/qemu_driver.c > @@ -8767,7 +8767,8 @@ qemuDomainMigrateBegin3(virDomainPtr domain, > goto endjob; > > if (!(xml = qemuMigrationBegin(driver, vm, xmlin, dname, > - cookieout, cookieoutlen))) > + cookieout, cookieoutlen, > + flags))) > goto endjob; > > if ((flags & VIR_MIGRATE_CHANGE_PROTECTION)) { > diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c > index f0af494..09494d6 100644 > --- a/src/qemu/qemu_migration.c > +++ b/src/qemu/qemu_migration.c > @@ -45,6 +45,7 @@ > #include "virtime.h" > #include "locking/domain_lock.h" > #include "rpc/virnetsocket.h" > +#include "storage_file.h" > > > #define VIR_FROM_THIS VIR_FROM_QEMU > @@ -817,6 +818,29 @@ qemuMigrationIsAllowed(struct qemud_driver *driver, virDomainObjPtr vm, > return true; > } > > +static bool > +qemuMigrationIsSafe(virDomainDefPtr def) > +{ > + int i; > + > + for (i = 0 ; i < def->ndisks ; i++) { > + virDomainDiskDefPtr disk = def->disks[i]; > + > + /* shared && !readonly implies cache=none */ > + if (disk->src && > + disk->cachemode != VIR_DOMAIN_DISK_CACHE_DISABLE && > + (disk->cachemode || !disk->shared || disk->readonly) && > + virStorageFileIsClusterFS(disk->src) == 1) { Isn't this test reversed. ie, we want to deny migration if *not* a cluster FS, eg == 0 surely ?