Re: [libvirt] [PATCH v4 6/6] qemu: Add support for hot/cold-(un)plug of shmem devices

This is needed in order to migrate a domain with shmem devices as that is not allowed to migrate. Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com&gt; --- src/qemu/qemu_driver.c | 39 +++- src/qemu/qemu_hotplug.c | 248 ++++++++++++++++++++- src/qemu/qemu_hotplug.h | 6 + tests/qemuhotplugtest.c | 21 ++ .../qemuhotplug-ivshmem-doorbell-detach.xml | 7 + .../qemuhotplug-ivshmem-doorbell.xml | 4 + .../qemuhotplug-ivshmem-plain-detach.xml | 6 + .../qemuhotplug-ivshmem-plain.xml | 3 + ...muhotplug-base-live+ivshmem-doorbell-detach.xml | 1 + .../qemuhotplug-base-live+ivshmem-doorbell.xml | 65 ++++++ .../qemuhotplug-base-live+ivshmem-plain-detach.xml | 1 + .../qemuhotplug-base-live+ivshmem-plain.xml | 58 +++++ 12 files changed, 454 insertions(+), 5 deletions(-) create mode 100644 tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-doorbell-detach.xml create mode 100644 tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-doorbell.xml create mode 100644 tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-plain-detach.xml create mode 100644 tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-plain.xml create mode 120000 tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-doorbell-detach.xml create mode 100644 tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-doorbell.xml create mode 120000 tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-plain-detach.xml create mode 100644 tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-plain.xml diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index bacabd2d348f..c164c390eccf 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -7601,6 +7601,15 @@ qemuDomainAttachDeviceLive(virDomainObjPtr vm, dev->data.memory = NULL; break; + case VIR_DOMAIN_DEVICE_SHMEM: + ret = qemuDomainAttachShmemDevice(driver, vm, + dev->data.shmem); + if (!ret) {

+ alias = dev->data.shmem->info.alias; + dev->data.shmem = NULL; + } + break; + case VIR_DOMAIN_DEVICE_NONE: case VIR_DOMAIN_DEVICE_FS: case VIR_DOMAIN_DEVICE_INPUT:

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index 7a21dc67f533..10236a0bccd9 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c

@@ -4271,6 +4455,68 @@ int qemuDomainDetachHostDevice(virQEMUDriverPtr driver, return qemuDomainDetachThisHostDevice(driver, vm, detach); } + +int +qemuDomainDetachShmemDevice(virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainShmemDefPtr dev) +{ + int ret = -1; + ssize_t idx = -1; + virErrorPtr orig_err = NULL; + virDomainShmemDefPtr shmem = NULL; + qemuDomainObjPrivatePtr priv = vm->privateData; + + if ((idx = virDomainShmemDefFind(vm->def, dev)) < 0) { + virReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("device not present in domain configuration")); + return -1; + } + + shmem = vm->def->shmems[idx]; + + switch ((virDomainShmemModel)shmem->model) { + case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_PLAIN: + case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_DOORBELL: + break; + + case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM: + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, + _("live detach of shmem model '%s' is not supported"), + virDomainShmemModelTypeToString(shmem->model)); + /* fall-through */ + case VIR_DOMAIN_SHMEM_MODEL_LAST: + return -1; + } + + qemuDomainMarkDeviceForRemoval(vm, &shmem->info); + qemuDomainObjEnterMonitor(driver, vm); + + ret = qemuMonitorDelDevice(priv->mon, shmem->info.alias); + + if (ret < 0) + orig_err = virSaveLastError();

+ + if (qemuDomainObjExitMonitor(driver, vm) < 0)

+ ret = -1; + + if (ret == 0) { + if ((ret = qemuDomainWaitForDeviceRemoval(vm)) == 1) { + qemuDomainReleaseDeviceAddress(vm, &shmem->info, NULL); + ret = qemuDomainRemoveShmemDevice(driver, vm, shmem); + } + } + qemuDomainResetDeviceRemoval(vm); + + if (orig_err) { + virSetError(orig_err); + virFreeError(orig_err); + }