[libvirt] [PATCH v3 REBASE 2 05/12] qemu: handle host usb device add/del udev events
Nikolay Shirokovskiy
nshirokovskiy at virtuozzo.com
Tue Oct 29 08:17:56 UTC 2019
Now when code handling attaching/detaching usb hostdev is appropriately
changed use it to handle host usb device udev add/del events.
As device adding/deleting needs acquiring job condition it is done in
thread pool rather in event loop thread itself where udev events are
delivered. However implementation in this patch is a bit different from
other places as we instead of finding right domain in event loop thread
and creating a single thread pool job create job for every vm. Such
a strategy allows us to avoid taking domain lock in event loop thread so
we have little chances to block event loop thread because some API
handler grabs domain lock for a significant amount of time.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy at virtuozzo.com>
---
src/qemu/Makefile.inc.am | 2 +
src/qemu/qemu_conf.h | 3 +
src/qemu/qemu_domain.c | 2 +
src/qemu/qemu_domain.h | 2 +
src/qemu/qemu_driver.c | 324 ++++++++++++++++++++++++++++++++++++++-
5 files changed, 332 insertions(+), 1 deletion(-)
diff --git a/src/qemu/Makefile.inc.am b/src/qemu/Makefile.inc.am
index 2074a5f54f..085a41d14f 100644
--- a/src/qemu/Makefile.inc.am
+++ b/src/qemu/Makefile.inc.am
@@ -98,6 +98,7 @@ libvirt_driver_qemu_impl_la_CFLAGS = \
-I$(srcdir)/conf \
-I$(srcdir)/secret \
$(AM_CFLAGS) \
+ $(UDEV_CFLAGS) \
$(NULL)
libvirt_driver_qemu_impl_la_LDFLAGS = $(AM_LDFLAGS)
libvirt_driver_qemu_impl_la_LIBADD = \
@@ -106,6 +107,7 @@ libvirt_driver_qemu_impl_la_LIBADD = \
$(LIBNL_LIBS) \
$(SELINUX_LIBS) \
$(LIBXML_LIBS) \
+ $(UDEV_LIBS) \
$(NULL)
libvirt_driver_qemu_impl_la_SOURCES = $(QEMU_DRIVER_SOURCES)
diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
index 7247199d3e..23c9b4d9fa 100644
--- a/src/qemu/qemu_conf.h
+++ b/src/qemu/qemu_conf.h
@@ -299,6 +299,9 @@ struct _virQEMUDriver {
/* Immutable pointer, self-locking APIs */
virHashAtomicPtr migrationErrors;
+
+ struct udev_monitor *udev_monitor;
+ int udev_watch;
};
virQEMUDriverConfigPtr virQEMUDriverConfigNew(bool privileged);
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 667cc89072..3d8e642625 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -15337,6 +15337,8 @@ qemuProcessEventFree(struct qemuProcessEvent *event)
case QEMU_PROCESS_EVENT_SERIAL_CHANGED:
case QEMU_PROCESS_EVENT_BLOCK_JOB:
case QEMU_PROCESS_EVENT_MONITOR_EOF:
+ case QEMU_PROCESS_EVENT_USB_REMOVED:
+ case QEMU_PROCESS_EVENT_USB_ADDED:
VIR_FREE(event->data);
break;
case QEMU_PROCESS_EVENT_JOB_STATUS_CHANGE:
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index b23912ee98..9571328c5c 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -549,6 +549,8 @@ typedef enum {
QEMU_PROCESS_EVENT_MONITOR_EOF,
QEMU_PROCESS_EVENT_PR_DISCONNECT,
QEMU_PROCESS_EVENT_RDMA_GID_STATUS_CHANGED,
+ QEMU_PROCESS_EVENT_USB_REMOVED,
+ QEMU_PROCESS_EVENT_USB_ADDED,
QEMU_PROCESS_EVENT_LAST
} qemuProcessEventType;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index d89676efc8..bcc3ff11e0 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -34,6 +34,7 @@
#include <sys/ioctl.h>
#include <sys/un.h>
#include <byteswap.h>
+#include <libudev.h>
#include "qemu_driver.h"
@@ -640,6 +641,221 @@ qemuDomainFindMaxID(virDomainObjPtr vm,
}
+struct qemuUdevUSBRemoveData {
+ unsigned int bus;
+ unsigned int device;
+};
+
+struct qemuUdevUSBAddData {
+ unsigned int vendor;
+ unsigned int product;
+};
+
+struct qemuUdevUSBEventData {
+ union {
+ struct qemuUdevUSBRemoveData remove;
+ struct qemuUdevUSBAddData add;
+ } data;
+ bool remove;
+};
+
+static int
+qemuUdevUSBHandleEvent(virDomainObjPtr vm, void *opaque)
+{
+ struct qemuUdevUSBEventData *data = opaque;
+ struct qemuProcessEvent *event = NULL;
+
+ if (VIR_ALLOC(event) < 0)
+ return 0;
+
+ if (data->remove) {
+ struct qemuUdevUSBRemoveData *rm_data;
+
+
+ if (VIR_ALLOC(rm_data) < 0)
+ goto cleanup;
+
+ *rm_data = data->data.remove;
+ event->data = rm_data;
+ event->eventType = QEMU_PROCESS_EVENT_USB_REMOVED;
+ } else {
+ struct qemuUdevUSBAddData *add_data;
+
+ if (VIR_ALLOC(add_data) < 0)
+ goto cleanup;
+
+ *add_data = data->data.add;
+ event->data = add_data;
+ event->eventType = QEMU_PROCESS_EVENT_USB_ADDED;
+ }
+
+ event->vm = virObjectRef(vm);
+
+ if (virThreadPoolSendJob(qemu_driver->workerPool, 0, event) < 0) {
+ virObjectUnref(vm);
+ goto cleanup;
+ }
+
+ event = NULL;
+
+ cleanup:
+ qemuProcessEventFree(event);
+
+ return 0;
+}
+
+
+static void
+qemuUdevEventHandleCallback(int watch G_GNUC_UNUSED,
+ int fd G_GNUC_UNUSED,
+ int events G_GNUC_UNUSED,
+ void *data G_GNUC_UNUSED)
+{
+ struct qemuUdevUSBEventData event_data;
+ struct udev_device *dev = NULL;
+ const char *action;
+ const char *devtype;
+ const char *tmp;
+
+ /* libvirtd daemon do not run event loop before full state drivers
+ * initialization. Also state drivers uninitialized only after
+ * full stop of event loop. In short driver initialization/uninitialization
+ * and handling events occurs in same main loop thread. Thus we
+ * don't need any locking here. */
+
+ if (!(dev = udev_monitor_receive_device(qemu_driver->udev_monitor))) {
+ VIR_WARNINGS_NO_WLOGICALOP_EQUAL_EXPR
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ VIR_WARNINGS_RESET
+ return;
+ }
+
+ virReportSystemError(errno, "%s",
+ _("failed to receive device from udev monitor"));
+ return;
+ }
+
+ devtype = udev_device_get_devtype(dev);
+
+ if (STRNEQ_NULLABLE(devtype, "usb_device"))
+ goto cleanup;
+
+ if (!(action = udev_device_get_action(dev))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to receive action from udev monitor"));
+ goto cleanup;
+ }
+
+ if (STREQ(action, "remove")) {
+ struct qemuUdevUSBRemoveData *rm_data = &event_data.data.remove;
+
+ if (!(tmp = udev_device_get_property_value(dev, "BUSNUM"))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to receive busnum from udev monitor"));
+ goto cleanup;
+ }
+ if (virStrToLong_ui(tmp, NULL, 10, &rm_data->bus) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to convert busnum to int"));
+ goto cleanup;
+ }
+
+ if (!(tmp = udev_device_get_property_value(dev, "DEVNUM"))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to receive devnum from udev monitor"));
+ goto cleanup;
+ }
+ if (virStrToLong_ui(tmp, NULL, 10, &rm_data->device) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to convert devnum to int"));
+ goto cleanup;
+ }
+ event_data.remove = true;
+ } else if (STREQ(action, "add")) {
+ struct qemuUdevUSBAddData *add_data = &event_data.data.add;
+
+ if (!(tmp = udev_device_get_property_value(dev, "ID_VENDOR_ID"))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to receive vendor from udev monitor"));
+ goto cleanup;
+ }
+ if (virStrToLong_ui(tmp, NULL, 16, &add_data->vendor) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to convert vendor to int"));
+ goto cleanup;
+ }
+
+ if (!(tmp = udev_device_get_property_value(dev, "ID_MODEL_ID"))) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to receive product from udev monitor"));
+ goto cleanup;
+ }
+ if (virStrToLong_ui(tmp, NULL, 16, &add_data->product) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to convert product to int"));
+ goto cleanup;
+ }
+ event_data.remove = false;
+ } else {
+ goto cleanup;
+ }
+
+ virDomainObjListForEach(qemu_driver->domains, false, qemuUdevUSBHandleEvent, &event_data);
+
+ cleanup:
+ udev_device_unref(dev);
+}
+
+
+static int
+qemuUdevInitialize(void)
+{
+ struct udev *udev;
+
+ if (!(udev = udev_new())) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("failed to create udev context"));
+ return -1;
+ }
+
+ if (!(qemu_driver->udev_monitor = udev_monitor_new_from_netlink(udev, "udev"))) {
+ udev_unref(udev);
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("udev_monitor_new_from_netlink returned NULL"));
+ return -1;
+ }
+
+ udev_monitor_enable_receiving(qemu_driver->udev_monitor);
+
+ qemu_driver->udev_watch = virEventAddHandle(udev_monitor_get_fd(qemu_driver->udev_monitor),
+ VIR_EVENT_HANDLE_READABLE,
+ qemuUdevEventHandleCallback, NULL, NULL);
+
+ if (qemu_driver->udev_watch < 0)
+ return -1;
+
+ return 0;
+}
+
+
+static void
+qemuUdevCleanup(void)
+{
+ if (qemu_driver->udev_monitor) {
+ struct udev *udev = udev_monitor_get_udev(qemu_driver->udev_monitor);
+
+ udev_monitor_unref(qemu_driver->udev_monitor);
+ udev_unref(udev);
+ qemu_driver->udev_monitor = NULL;
+ }
+
+ if (qemu_driver->udev_watch > 0) {
+ virEventRemoveHandle(qemu_driver->udev_watch);
+ qemu_driver->udev_watch = 0;
+ }
+}
+
+
/**
* qemuStateInitialize:
*
@@ -960,6 +1176,9 @@ qemuStateInitialize(bool privileged,
if (!(qemu_driver->closeCallbacks = virCloseCallbacksNew()))
goto error;
+ if (qemuUdevInitialize() < 0)
+ goto error;
+
/* Get all the running persistent or transient configs first */
if (virDomainObjListLoadAllConfigs(qemu_driver->domains,
cfg->stateDir,
@@ -1169,6 +1388,8 @@ qemuStateCleanup(void)
virLockManagerPluginUnref(qemu_driver->lockManager);
+ qemuUdevCleanup();
+
virMutexDestroy(&qemu_driver->lock);
VIR_FREE(qemu_driver);
@@ -4839,7 +5060,102 @@ processRdmaGidStatusChangedEvent(virDomainObjPtr vm,
}
-static void qemuProcessEventHandler(void *data, void *opaque)
+static void
+processUSBAddedEvent(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ struct qemuUdevUSBAddData *data)
+{
+ virDomainHostdevDefPtr hostdev;
+ virDomainHostdevSubsysUSBPtr usbsrc;
+ size_t i;
+
+ if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
+ return;
+
+ if (!virDomainObjIsActive(vm)) {
+ VIR_DEBUG("Domain is not running");
+ goto cleanup;
+ }
+
+ for (i = 0; i < vm->def->nhostdevs; i++) {
+ hostdev = vm->def->hostdevs[i];
+
+ if (hostdev->source.subsys.type != VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_USB)
+ continue;
+
+ usbsrc = &hostdev->source.subsys.u.usb;
+
+ if (!usbsrc->replug)
+ continue;
+
+ if (usbsrc->vendor == data->vendor && usbsrc->product == data->product)
+ break;
+ }
+
+ if (i == vm->def->nhostdevs)
+ goto cleanup;
+
+ if (qemuDomainAttachHostDevice(driver, vm, hostdev) < 0)
+ goto cleanup;
+
+ cleanup:
+ qemuDomainObjEndJob(driver, vm);
+}
+
+
+static void
+processUSBRemovedEvent(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ struct qemuUdevUSBRemoveData *data)
+{
+ size_t i;
+ virDomainHostdevDefPtr hostdev;
+ virDomainDeviceDef dev = { .type = VIR_DOMAIN_DEVICE_HOSTDEV };
+
+ if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
+ return;
+
+ if (!virDomainObjIsActive(vm)) {
+ VIR_DEBUG("Domain is not running");
+ goto cleanup;
+ }
+
+ for (i = 0; i < vm->def->nhostdevs; i++) {
+ virDomainHostdevSubsysUSBPtr usbsrc;
+
+ hostdev = vm->def->hostdevs[i];
+ if (hostdev->source.subsys.type != VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_USB)
+ continue;
+
+ usbsrc = &hostdev->source.subsys.u.usb;
+
+ if (!usbsrc->replug)
+ continue;
+
+ /* don't mess with devices that don't use stable host addressing
+ * with respect to unplug/plug to host
+ */
+ if (!usbsrc->vendor || !usbsrc->product)
+ continue;
+
+ if (usbsrc->bus == data->bus && usbsrc->device == data->device)
+ break;
+ }
+
+ if (i == vm->def->nhostdevs)
+ goto cleanup;
+
+ dev.data.hostdev = hostdev;
+ if (qemuDomainDetachDeviceLive(vm, &dev, driver, true, true) < 0)
+ goto cleanup;
+
+ cleanup:
+ qemuDomainObjEndJob(driver, vm);
+}
+
+
+static void
+qemuProcessEventHandler(void *data, void *opaque)
{
struct qemuProcessEvent *processEvent = data;
virDomainObjPtr vm = processEvent->vm;
@@ -4885,6 +5201,12 @@ static void qemuProcessEventHandler(void *data, void *opaque)
case QEMU_PROCESS_EVENT_RDMA_GID_STATUS_CHANGED:
processRdmaGidStatusChangedEvent(vm, processEvent->data);
break;
+ case QEMU_PROCESS_EVENT_USB_REMOVED:
+ processUSBRemovedEvent(driver, vm, processEvent->data);
+ break;
+ case QEMU_PROCESS_EVENT_USB_ADDED:
+ processUSBAddedEvent(driver, vm, processEvent->data);
+ break;
case QEMU_PROCESS_EVENT_LAST:
break;
}
--
2.23.0
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