Re: [libvirt] [PATCH] Support virDomainAttachDevice and virDomainDetachDevice for disks in UML

From: Soren Hansen <soren(a)linux2go.dk&gt; UML supports hot plugging and unplugging of various devices. This patch exposes this functionality for disks.

Signed-off-by: Soren Hansen <soren(a)linux2go.dk&gt; --- src/uml/uml_driver.c | 223 +++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 221 insertions(+), 2 deletions(-) diff --git a/src/uml/uml_driver.c b/src/uml/uml_driver.c index 04493ba..a09bc60 100644 --- a/src/uml/uml_driver.c +++ b/src/uml/uml_driver.c @@ -1686,6 +1686,225 @@ cleanup: } +static inline void umlShrinkDisks(virDomainDefPtr def, size_t i) +{ + if (def->ndisks > 1) { + memmove(def->disks + i, + def->disks + i + 1, + sizeof(*def->disks) * + (def->ndisks - (i + 1))); + def->ndisks--; + if (VIR_REALLOC_N(def->disks, def->ndisks) < 0) { + /* ignore, harmless */ + } + } else { + VIR_FREE(def->disks); + def->ndisks = 0; + } +}

+ + +static int umlDomainAttachUmlDisk(struct uml_driver *driver, + virDomainObjPtr vm, + virDomainDiskDefPtr disk) +{ + int i, ret; + char *cmd = NULL; + char *reply; + + for (i = 0 ; i < vm->def->ndisks ; i++) { + if (STREQ(vm->def->disks[i]->dst, disk->dst)) { + umlReportError(VIR_ERR_OPERATION_FAILED, + _("target %s already exists"), disk->dst); + return -1; + } + } + + if (!disk->src) { + umlReportError(VIR_ERR_INTERNAL_ERROR, + "%s", _("disk source path is missing")); + goto error; + } + + if (virAsprintf(&cmd, "config %s=%s", disk->dst, disk->src) < 0) { + virReportOOMError(); + return -1; + } + + if (umlMonitorCommand(driver, vm, cmd, &reply) < 0) + return -1;

+ + if (VIR_REALLOC_N(vm->def->disks, vm->def->ndisks+1) < 0) { + virReportOOMError(); + goto error; + } + + if (ret < 0) + goto error; + + virDomainDiskInsertPreAlloced(vm->def, disk); + + VIR_FREE(cmd); + + return 0; + +error: + + VIR_FREE(cmd); + + return -1; +}

+ dev = virDomainDeviceDefParse(driver->caps, vm->def, xml, + VIR_DOMAIN_XML_INACTIVE); + if (dev == NULL) + goto cleanup; + + if (dev->type == VIR_DOMAIN_DEVICE_DISK && + dev->data.disk->device == VIR_DOMAIN_DISK_DEVICE_DISK) { + if (dev->data.disk->bus == VIR_DOMAIN_DISK_BUS_UML) + ret = umlDomainDetachUmlDisk(driver, vm, dev); + else { + umlReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("This type of disk cannot be hot unplugged")); + } + } else { + umlReportError(VIR_ERR_CONFIG_UNSUPPORTED, + "%s", _("This type of device cannot be hot unplugged")); + } + +cleanup: + virDomainDeviceDefFree(dev); + if (vm) + virDomainObjUnlock(vm); + umlDriverUnlock(driver); + return ret; +} + static int umlDomainGetAutostart(virDomainPtr dom, int *autostart) { @@ -1900,9 +2119,9 @@ static virDriver umlDriver = { umlDomainStartWithFlags, /* domainCreateWithFlags */ umlDomainDefine, /* domainDefineXML */ umlDomainUndefine, /* domainUndefine */ - NULL, /* domainAttachDevice */ + umlDomainAttachDevice, /* domainAttachDevice */ NULL, /* domainAttachDeviceFlags */ - NULL, /* domainDetachDevice */ + umlDomainDetachDevice, /* domainDetachDevice */ NULL, /* domainDetachDeviceFlags */