[libvirt] [PATCH 05/10] Add higher level lock API for domain objects

To facilitate use of the locking plugins from hypervisor drivers, introduce a higher level API for locking virDomainObjPtr instances. In includes APIs targetted to VM startup, and hotplug/unplug * src/Makefile.am: Add domain lock API * src/locking/domain_lock.c, src/locking/domain_lock.h: High level API for domain locking --- src/Makefile.am | 3 +- src/libvirt_private.syms | 11 ++ src/locking/README | 7 + src/locking/domain_lock.c | 284 +++++++++++++++++++++++++++++++++++++++++++++ src/locking/domain_lock.h | 56 +++++++++ 5 files changed, 360 insertions(+), 1 deletions(-) create mode 100644 src/locking/domain_lock.c create mode 100644 src/locking/domain_lock.h diff --git a/src/Makefile.am b/src/Makefile.am index 96e2edf..1e5a72e 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -96,7 +96,8 @@ DRIVER_SOURCES = \ libvirt.c libvirt_internal.h \ locking/lock_manager.c locking/lock_manager.h \ locking/lock_driver.h \ - locking/lock_driver_nop.h locking/lock_driver_nop.c + locking/lock_driver_nop.h locking/lock_driver_nop.c \ + locking/domain_lock.h locking/domain_lock.c # XML configuration format handling sources diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 1784c0d..a2a6de9 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -407,6 +407,17 @@ virDomainEventWatchdogNewFromDom; virDomainEventWatchdogNewFromObj; +# domain_lock.h +virDomainLockProcessStart; +virDomainLockProcessInquire; +virDomainLockProcessPause; +virDomainLockProcessResume; +virDomainLockDiskAttach; +virDomainLockDiskDetach; +virDomainLockLeaseAttach; +virDomainLockLeaseDetach; + + # domain_nwfilter.h virDomainConfNWFilterInstantiate; virDomainConfNWFilterRegister; diff --git a/src/locking/README b/src/locking/README index 4fa4f89..da2a8f8 100644 --- a/src/locking/README +++ b/src/locking/README @@ -1,3 +1,10 @@ + Using the Lock Manager APIs + =========================== + +This file describes how to use the lock manager APIs. +All the guest lifecycle sequences here have higher +level wrappers provided by the 'domain_lock.h' API, +which simplify thue usage At libvirtd startup: diff --git a/src/locking/domain_lock.c b/src/locking/domain_lock.c new file mode 100644 index 0000000..85352e2 --- /dev/null +++ b/src/locking/domain_lock.c @@ -0,0 +1,284 @@ +/* + * domain_lock.c: Locking for domain lifecycle operations + * + * Copyright (C) 2010-2011 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <config.h> + +#include <intprops.h> + +#include "domain_lock.h" +#include "memory.h" +#include "uuid.h" +#include "virterror_internal.h" +#include "logging.h" + +#define VIR_FROM_THIS VIR_FROM_LOCKING + + +static int virDomainLockManagerAddLease(virLockManagerPtr lock, + virDomainLeaseDefPtr lease) +{ + unsigned int leaseFlags = 0; + virLockManagerParam lparams[] = { + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_STRING, + .key = "path", + .value = { .str = lease->path }, + }, + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_ULONG, + .key = "offset", + .value = { .ul = lease->offset }, + }, + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_STRING, + .key = "lockspace", + .value = { .str = lease->lockspace }, + }, + }; + size_t nparams = ARRAY_CARDINALITY(lparams); + if (!lease->lockspace) + nparams--; + + VIR_DEBUG("Add lease %s", lease->path); + if (virLockManagerAddResource(lock, + VIR_LOCK_MANAGER_RESOURCE_TYPE_LEASE, + lease->key, + nparams, + lparams, + leaseFlags) < 0) { + VIR_DEBUG("Failed to add lease %s", lease->path); + return -1; + } + return 0; +} + + +static int virDomainLockManagerAddDisk(virLockManagerPtr lock, + virDomainDiskDefPtr disk) +{ + unsigned int diskFlags = 0; + if (!disk->src) + return 0; + + if (!(disk->type == VIR_DOMAIN_DISK_TYPE_BLOCK || + disk->type == VIR_DOMAIN_DISK_TYPE_FILE || + disk->type == VIR_DOMAIN_DISK_TYPE_DIR)) + return 0; + + if (disk->readonly) + diskFlags |= VIR_LOCK_MANAGER_RESOURCE_READONLY; + if (disk->shared) + diskFlags |= VIR_LOCK_MANAGER_RESOURCE_SHARED; + + VIR_DEBUG("Add disk %s", disk->src); + if (virLockManagerAddResource(lock, + VIR_LOCK_MANAGER_RESOURCE_TYPE_DISK, + disk->src, + 0, + NULL, + diskFlags) < 0) { + VIR_DEBUG("Failed add disk %s", disk->src); + return -1; + } + return 0; +} + +static virLockManagerPtr virDomainLockManagerNew(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + bool withResources) +{ + virLockManagerPtr lock; + int i; + virLockManagerParam params[] = { + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_UUID, + .key = "uuid", + }, + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_STRING, + .key = "name", + .value = { .str = dom->def->name }, + }, + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_UINT, + .key = "id", + .value = { .i = dom->def->id }, + }, + { .type = VIR_LOCK_MANAGER_PARAM_TYPE_UINT, + .key = "pid", + .value = { .i = dom->pid }, + }, + }; + VIR_DEBUG("plugin=%p dom=%p withResources=%d", + plugin, dom, withResources); + + memcpy(params[0].value.uuid, dom->def->uuid, VIR_UUID_BUFLEN); + + if (!(lock = virLockManagerNew(plugin, + VIR_LOCK_MANAGER_OBJECT_TYPE_DOMAIN, + ARRAY_CARDINALITY(params), + params, + 0))) + goto error; + + if (withResources) { + VIR_DEBUG("Adding leases"); + for (i = 0 ; i < dom->def->nleases ; i++) + if (virDomainLockManagerAddLease(lock, dom->def->leases[i]) < 0) + goto error; + + VIR_DEBUG("Adding disks"); + for (i = 0 ; i < dom->def->ndisks ; i++) + if (virDomainLockManagerAddDisk(lock, dom->def->disks[i]) < 0) + goto error; + } + + return lock; + +error: + virLockManagerFree(lock); + return NULL; +} + + +int virDomainLockProcessStart(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + bool paused) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, true); + int ret; + if (paused) + ret = virLockManagerAcquire(lock, NULL, VIR_LOCK_MANAGER_ACQUIRE_REGISTER_ONLY); + else + ret = virLockManagerAcquire(lock, NULL, 0); + + virLockManagerFree(lock); + + return ret; +} + +int virDomainLockProcessPause(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + char **state) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, true); + int ret = virLockManagerRelease(lock, state, 0); + + virLockManagerFree(lock); + + return ret; +} + +int virDomainLockProcessResume(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + const char *state) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, true); + int ret = virLockManagerAcquire(lock, state, 0); + + virLockManagerFree(lock); + + return ret; +} + +int virDomainLockProcessInquire(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + char **state) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, true); + int ret = virLockManagerInquire(lock, state, 0); + + virLockManagerFree(lock); + + return ret; +} + + +int virDomainLockDiskAttach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainDiskDefPtr disk) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, false); + int ret = -1; + + if (virDomainLockManagerAddDisk(lock, disk) < 0) + goto cleanup; + + if (virLockManagerAcquire(lock, NULL, 0) < 0) + goto cleanup; + +cleanup: + virLockManagerFree(lock); + + return ret; +} + +int virDomainLockDiskDetach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainDiskDefPtr disk) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, false); + int ret = -1; + + if (virDomainLockManagerAddDisk(lock, disk) < 0) + goto cleanup; + + if (virLockManagerRelease(lock, NULL, 0) < 0) + goto cleanup; + +cleanup: + virLockManagerFree(lock); + + return ret; +} + + +int virDomainLockLeaseAttach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainLeaseDefPtr lease) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, false); + int ret = -1; + + if (virDomainLockManagerAddLease(lock, lease) < 0) + goto cleanup; + + if (virLockManagerAcquire(lock, NULL, 0) < 0) + goto cleanup; + +cleanup: + virLockManagerFree(lock); + + return ret; +} + +int virDomainLockLeaseDetach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainLeaseDefPtr lease) +{ + virLockManagerPtr lock = virDomainLockManagerNew(plugin, dom, false); + int ret = -1; + + if (virDomainLockManagerAddLease(lock, lease) < 0) + goto cleanup; + + if (virLockManagerRelease(lock, NULL, 0) < 0) + goto cleanup; + +cleanup: + virLockManagerFree(lock); + + return ret; +} diff --git a/src/locking/domain_lock.h b/src/locking/domain_lock.h new file mode 100644 index 0000000..40fadd4 --- /dev/null +++ b/src/locking/domain_lock.h @@ -0,0 +1,56 @@ +/* + * domain_lock.c: Locking for domain lifecycle operations + * + * Copyright (C) 2010-2011 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#ifndef __VIR_DOMAIN_LOCK_H__ +# define __VIR_DOMAIN_LOCK_H__ + +# include "internal.h" +# include "domain_conf.h" +# include "lock_manager.h" + +int virDomainLockProcessStart(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + bool paused); +int virDomainLockProcessPause(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + char **state); +int virDomainLockProcessResume(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + const char *state); +int virDomainLockProcessInquire(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + char **state); + +int virDomainLockDiskAttach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainDiskDefPtr disk); +int virDomainLockDiskDetach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainDiskDefPtr disk); + +int virDomainLockLeaseAttach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainLeaseDefPtr lease); +int virDomainLockLeaseDetach(virLockManagerPluginPtr plugin, + virDomainObjPtr dom, + virDomainLeaseDefPtr lease); + +#endif /* __VIR_DOMAIN_LOCK_H__ */ -- 1.7.4.4