Re: [libvirt] [PATCH 2/4] Avoid create/unlink with block devs used for QEMU save

It is possible to use block devices with domain save/restore. Upon failure QEMU unlinks the path being saved to. This isn't good when it is a block device ! * src/qemu/qemu_driver.c: Don't unlink block devices if save fails --- src/qemu/qemu_driver.c | 22 ++++++++++++++++++++-- 1 files changed, 20 insertions(+), 2 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 91fe963..41a516c 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4787,6 +4787,8 @@ static int qemudDomainSaveFlag(virDomainPtr dom, const char *path, int rc; virDomainEventPtr event = NULL; qemuDomainObjPrivatePtr priv; + struct stat sb; + int is_reg = 0; memset(&header, 0, sizeof(header)); memcpy(header.magic, QEMUD_SAVE_MAGIC, sizeof(header.magic)); @@ -4840,6 +4842,21 @@ static int qemudDomainSaveFlag(virDomainPtr dom, const char *path, } header.xml_len = strlen(xml) + 1; + /* path might be a pre-existing block dev, in which case + * we need to skip the create step, and also avoid unlink + * in the failure case */ + if (stat(path,&sb)< 0) { + if (errno != ENOENT) {