[libvirt PATCH v6 11/30] nodedev: add mdevctl devices to node device list
Jonathon Jongsma
jjongsma at redhat.com
Fri Mar 26 16:48:07 UTC 2021
At startup, query devices that are defined by 'mdevctl' and add them to
the node device list.
This adds a complication: we now have two potential sources of
information for a node device:
- udev for all devices and for activated mediated devices
- mdevctl for persistent mediated devices
Unfortunately, neither backend returns full information for a mediated
device. For example, if a persistent mediated device in the list (with
information provided from mdevctl) is 'started', that same device will
now be detected by udev. If we simply overwrite the existing device
definition with the new one provided by the udev backend, we will lose
extra information that was provided by mdevctl (e.g. attributes, etc).
To avoid this, make sure to copy the extra information into the new
device definition.
Signed-off-by: Jonathon Jongsma <jjongsma at redhat.com>
---
src/node_device/node_device_driver.c | 153 +++++++++++++++++++++++++++
src/node_device/node_device_driver.h | 6 ++
src/node_device/node_device_udev.c | 31 +++++-
3 files changed, 185 insertions(+), 5 deletions(-)
diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c
index 6911fa36da..efa524f317 100644
--- a/src/node_device/node_device_driver.c
+++ b/src/node_device/node_device_driver.c
@@ -1164,3 +1164,156 @@ nodeDeviceGenerateName(virNodeDeviceDef *def,
*(def->name + i) = '_';
}
}
+
+
+static int
+virMdevctlListDefined(virNodeDeviceDef ***devs)
+{
+ int status;
+ g_autofree char *output = NULL;
+ g_autoptr(virCommand) cmd = nodeDeviceGetMdevctlListCommand(true, &output);
+
+ if (virCommandRun(cmd, &status) < 0 || status != 0)
+ return -1;
+
+ if (!output)
+ return -1;
+
+ return nodeDeviceParseMdevctlJSON(output, devs);
+}
+
+
+int
+nodeDeviceUpdateMediatedDevices(void)
+{
+ g_autofree virNodeDeviceDef **defs = NULL;
+ int ndefs;
+ size_t i;
+
+ if ((ndefs = virMdevctlListDefined(&defs)) < 0) {
+ virReportSystemError(errno, "%s",
+ _("failed to query mdevs from mdevctl"));
+ return -1;
+ }
+
+ for (i = 0; i < ndefs; i++) {
+ virNodeDeviceObj *obj;
+ virObjectEvent *event;
+ g_autoptr(virNodeDeviceDef) def = defs[i];
+ g_autofree char *name = g_strdup(def->name);
+ bool defined = false;
+
+ def->driver = g_strdup("vfio_mdev");
+
+ if (!(obj = virNodeDeviceObjListFindByName(driver->devs, def->name))) {
+ virNodeDeviceDef *d = g_steal_pointer(&def);
+ if (!(obj = virNodeDeviceObjListAssignDef(driver->devs, d))) {
+ virNodeDeviceDefFree(d);
+ return -1;
+ }
+ } else {
+ bool changed;
+ virNodeDeviceDef *olddef = virNodeDeviceObjGetDef(obj);
+
+ defined = virNodeDeviceObjIsPersistent(obj);
+ /* Active devices contain some additional information (e.g. sysfs
+ * path) that is not provided by mdevctl, so re-use the existing
+ * definition and copy over new mdev data */
+ changed = nodeDeviceDefCopyFromMdevctl(olddef, def);
+
+ if (defined && !changed) {
+ /* if this device was already defined and the definition
+ * hasn't changed, there's nothing to do for this device */
+ virNodeDeviceObjEndAPI(&obj);
+ continue;
+ }
+ }
+
+ /* all devices returned by virMdevctlListDefined() are persistent */
+ virNodeDeviceObjSetPersistent(obj, true);
+
+ if (!defined)
+ event = virNodeDeviceEventLifecycleNew(name,
+ VIR_NODE_DEVICE_EVENT_DEFINED,
+ 0);
+ else
+ event = virNodeDeviceEventUpdateNew(name);
+
+ virNodeDeviceObjEndAPI(&obj);
+ virObjectEventStateQueue(driver->nodeDeviceEventState, event);
+ }
+
+ return 0;
+}
+
+
+/* returns true if any attributes were copied, else returns false */
+static bool
+virMediatedDeviceAttrsCopy(virNodeDevCapMdev *dst,
+ virNodeDevCapMdev *src)
+{
+ bool ret = false;
+ size_t i;
+
+ if (src->nattributes != dst->nattributes) {
+ ret = true;
+ for (i = 0; i < dst->nattributes; i++)
+ virMediatedDeviceAttrFree(dst->attributes[i]);
+ g_free(dst->attributes);
+
+ dst->nattributes = src->nattributes;
+ dst->attributes = g_new0(virMediatedDeviceAttr*,
+ src->nattributes);
+ for (i = 0; i < dst->nattributes; i++)
+ dst->attributes[i] = virMediatedDeviceAttrNew();
+ }
+
+ for (i = 0; i < src->nattributes; i++) {
+ if (STRNEQ_NULLABLE(src->attributes[i]->name,
+ dst->attributes[i]->name)) {
+ ret = true;
+ g_free(dst->attributes[i]->name);
+ dst->attributes[i]->name =
+ g_strdup(src->attributes[i]->name);
+ }
+ if (STRNEQ_NULLABLE(src->attributes[i]->value,
+ dst->attributes[i]->value)) {
+ ret = true;
+ g_free(dst->attributes[i]->value);
+ dst->attributes[i]->value =
+ g_strdup(src->attributes[i]->value);
+ }
+ }
+
+ return ret;
+}
+
+
+/* A mediated device definitions from mdevctl contains additional info that is
+ * not available from udev. Transfer this data to the new definition.
+ * Returns true if anything was copied, else returns false */
+bool
+nodeDeviceDefCopyFromMdevctl(virNodeDeviceDef *dst,
+ virNodeDeviceDef *src)
+{
+ bool ret = false;
+ virNodeDevCapMdev *srcmdev = &src->caps->data.mdev;
+ virNodeDevCapMdev *dstmdev = &dst->caps->data.mdev;
+
+ if (STRNEQ_NULLABLE(dstmdev->type, srcmdev->type)) {
+ ret = true;
+ g_free(dstmdev->type);
+ dstmdev->type = g_strdup(srcmdev->type);
+ }
+
+ if (STRNEQ_NULLABLE(dstmdev->uuid, srcmdev->uuid)) {
+ ret = true;
+ g_free(dstmdev->uuid);
+ dstmdev->uuid = g_strdup(srcmdev->uuid);
+ }
+
+ if (virMediatedDeviceAttrsCopy(dstmdev, srcmdev))
+ ret = true;
+
+ return ret;
+}
diff --git a/src/node_device/node_device_driver.h b/src/node_device/node_device_driver.h
index 705d83f827..9b54efe4e3 100644
--- a/src/node_device/node_device_driver.h
+++ b/src/node_device/node_device_driver.h
@@ -128,8 +128,14 @@ int
nodeDeviceParseMdevctlJSON(const char *jsonstring,
virNodeDeviceDef ***devs);
+int
+nodeDeviceUpdateMediatedDevices(void);
+
void
nodeDeviceGenerateName(virNodeDeviceDef *def,
const char *subsystem,
const char *sysname,
const char *s);
+
+bool nodeDeviceDefCopyFromMdevctl(virNodeDeviceDef *dst,
+ virNodeDeviceDef *src);
diff --git a/src/node_device/node_device_udev.c b/src/node_device/node_device_udev.c
index eae301cc95..38ebe7b5c5 100644
--- a/src/node_device/node_device_udev.c
+++ b/src/node_device/node_device_udev.c
@@ -1421,9 +1421,17 @@ udevRemoveOneDeviceSysPath(const char *path)
VIR_NODE_DEVICE_EVENT_DELETED,
0);
- VIR_DEBUG("Removing device '%s' with sysfs path '%s'",
- def->name, path);
- virNodeDeviceObjListRemove(driver->devs, obj);
+ /* If the device is a mediated device that has been 'stopped', it may still
+ * be defined by mdevctl and can therefore be started again. Don't drop it
+ * from the list of node devices */
+ if (virNodeDeviceObjIsPersistent(obj)) {
+ VIR_FREE(def->sysfs_path);
+ virNodeDeviceObjSetActive(obj, false);
+ } else {
+ VIR_DEBUG("Removing device '%s' with sysfs path '%s'",
+ def->name, path);
+ virNodeDeviceObjListRemove(driver->devs, obj);
+ }
virNodeDeviceObjEndAPI(&obj);
virObjectEventStateQueue(driver->nodeDeviceEventState, event);
@@ -1481,7 +1489,6 @@ udevSetParent(struct udev_device *device,
return 0;
}
-
static int
udevAddOneDevice(struct udev_device *device)
{
@@ -1491,6 +1498,7 @@ udevAddOneDevice(struct udev_device *device)
virObjectEventPtr event = NULL;
bool new_device = true;
int ret = -1;
+ bool was_persistent = false;
def = g_new0(virNodeDeviceDef, 1);
@@ -1514,14 +1522,23 @@ udevAddOneDevice(struct udev_device *device)
goto cleanup;
if ((obj = virNodeDeviceObjListFindByName(driver->devs, def->name))) {
+ objdef = virNodeDeviceObjGetDef(obj);
+
+ if (def->caps->data.type == VIR_NODE_DEV_CAP_MDEV)
+ nodeDeviceDefCopyFromMdevctl(def, objdef);
+ was_persistent = virNodeDeviceObjIsPersistent(obj);
+ /* If the device was defined by mdevctl and was never instantiated, it
+ * won't have a sysfs path. We need to emit a CREATED event... */
+ new_device = (objdef->sysfs_path == NULL);
+
virNodeDeviceObjEndAPI(&obj);
- new_device = false;
}
/* If this is a device change, the old definition will be freed
* and the current definition will take its place. */
if (!(obj = virNodeDeviceObjListAssignDef(driver->devs, def)))
goto cleanup;
+ virNodeDeviceObjSetPersistent(obj, was_persistent);
objdef = virNodeDeviceObjGetDef(obj);
if (new_device)
@@ -1941,6 +1958,10 @@ nodeStateInitializeEnumerate(void *opaque)
/* Populate with known devices */
if (udevEnumerateDevices(udev) != 0)
goto error;
+ /* Load persistent mdevs (which might not be activated yet) and additional
+ * information about active mediated devices from mdevctl */
+ if (nodeDeviceUpdateMediatedDevices() != 0)
+ goto error;
nodeDeviceLock();
driver->initialized = true;
--
2.26.3
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