[libvirt] [PATCHv2 4/4] qemu: Implement shared memory device hot-unplug

[Luyao Huang]

Signed-off-by: Luyao Huang <lhuang at redhat.com>
---
 src/qemu/qemu_driver.c  |  4 ++-
 src/qemu/qemu_hotplug.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++-
 src/qemu/qemu_hotplug.h |  3 ++
 3 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 3c25c07..9e7429a 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -7881,6 +7881,9 @@ qemuDomainDetachDeviceLive(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_MEMORY:
         ret = qemuDomainDetachMemoryDevice(driver, vm, dev->data.memory);
         break;
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainDetachShmemDevice(driver, vm, dev->data.shmem);
+        break;
 
     case VIR_DOMAIN_DEVICE_FS:
     case VIR_DOMAIN_DEVICE_INPUT:
@@ -7892,7 +7895,6 @@ qemuDomainDetachDeviceLive(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_REDIRDEV:
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_TPM:
diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index c5e544d..4ab05f3 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -3347,6 +3347,45 @@ qemuDomainRemoveRNGDevice(virQEMUDriverPtr driver,
 }
 
 
+static int
+qemuDomainRemoveShmemDevice(virQEMUDriverPtr driver,
+                            virDomainObjPtr vm,
+                            virDomainShmemDefPtr shmem)
+{
+    virObjectEventPtr event;
+    char *charAlias = NULL;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    ssize_t idx;
+    int rc = 0;
+
+    VIR_DEBUG("Removing shared memory device %s from domain %p %s",
+              shmem->info.alias, vm, vm->def->name);
+
+    if (shmem->server.enabled) {
+        if (virAsprintf(&charAlias, "char%s", shmem->info.alias) < 0)
+            return -1;
+
+        qemuDomainObjEnterMonitor(driver, vm);
+        rc = qemuMonitorDetachCharDev(priv->mon, charAlias);
+        VIR_FREE(charAlias);
+        if (qemuDomainObjExitMonitor(driver, vm) < 0)
+            return -1;
+    }
+
+    if (rc < 0)
+        return -1;
+
+    if ((event = virDomainEventDeviceRemovedNewFromObj(vm, shmem->info.alias)))
+        qemuDomainEventQueue(driver, event);
+
+    if ((idx = virDomainShmemFind(vm->def, shmem, true)) >= 0)
+        virDomainShmemRemove(vm->def, idx);
+    qemuDomainReleaseDeviceAddress(vm, &shmem->info, NULL);
+    virDomainShmemDefFree(shmem);
+    return 0;
+}
+
+
 int
 qemuDomainRemoveDevice(virQEMUDriverPtr driver,
                        virDomainObjPtr vm,
@@ -3378,6 +3417,10 @@ qemuDomainRemoveDevice(virQEMUDriverPtr driver,
         ret = qemuDomainRemoveMemoryDevice(driver, vm, dev->data.memory);
         break;
 
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainRemoveShmemDevice(driver, vm, dev->data.shmem);
+        break;
+
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_LEASE:
     case VIR_DOMAIN_DEVICE_FS:
@@ -3391,7 +3434,6 @@ qemuDomainRemoveDevice(virQEMUDriverPtr driver,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_TPM:
     case VIR_DOMAIN_DEVICE_PANIC:
     case VIR_DOMAIN_DEVICE_LAST:
@@ -4378,3 +4420,53 @@ qemuDomainDetachMemoryDevice(virQEMUDriverPtr driver,
     qemuDomainResetDeviceRemoval(vm);
     return ret;
 }
+
+
+int
+qemuDomainDetachShmemDevice(virQEMUDriverPtr driver,
+                            virDomainObjPtr vm,
+                            virDomainShmemDefPtr shmem)
+{
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    ssize_t idx;
+    virDomainShmemDefPtr tmpshmem;
+    int rc;
+    int ret = -1;
+
+    if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE)) {
+        virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                       _("qemu does not support -device"));
+        return -1;
+    }
+
+    if ((idx = virDomainShmemFind(vm->def, shmem, true)) < 0) {
+        virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                       _("device not present in domain configuration"));
+        return -1;
+    }
+
+    tmpshmem = vm->def->shmems[idx];
+
+    if (!tmpshmem->info.alias) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("alias not set for shared memory device"));
+        return -1;
+    }
+
+    qemuDomainMarkDeviceForRemoval(vm, &tmpshmem->info);
+
+    qemuDomainObjEnterMonitor(driver, vm);
+    rc = qemuMonitorDelDevice(priv->mon, tmpshmem->info.alias);
+    if (qemuDomainObjExitMonitor(driver, vm) || rc < 0)
+        goto cleanup;
+
+    rc = qemuDomainWaitForDeviceRemoval(vm);
+    if (rc == 0 || rc == 1)
+        ret = qemuDomainRemoveShmemDevice(driver, vm, tmpshmem);
+    else
+        ret = 0;
+
+ cleanup:
+    qemuDomainResetDeviceRemoval(vm);
+    return ret;
+}
diff --git a/src/qemu/qemu_hotplug.h b/src/qemu/qemu_hotplug.h
index 60137a6..1b18e8a 100644
--- a/src/qemu/qemu_hotplug.h
+++ b/src/qemu/qemu_hotplug.h
@@ -112,6 +112,9 @@ int qemuDomainDetachRNGDevice(virQEMUDriverPtr driver,
 int qemuDomainAttachShmemDevice(virQEMUDriverPtr driver,
                                 virDomainObjPtr vm,
                                 virDomainShmemDefPtr shmem);
+int qemuDomainDetachShmemDevice(virQEMUDriverPtr driver,
+                                virDomainObjPtr vm,
+                                virDomainShmemDefPtr shmem);
 
 int
 qemuDomainChrInsert(virDomainDefPtr vmdef,
-- 
1.8.3.1