On 6/9/20 11:43 PM, Jonathon Jongsma wrote:
With recent additions to the node device xml schema, an xml schema can
now describe a mdev device sufficiently for libvirt to create and start
the device using the mdevctl utility.
Note that some of the the configuration for a mediated device must be
passed to mdevctl as a JSON-formatted file. In order to avoid creating
and cleaning up temporary files, the JSON is instead fed to stdin and we
pass the filename /dev/stdin to mdevctl. While this may not be portable,
neither are mediated devices, so I don't believe it should cause any
problems.
Agreed. mdevs are Linux specific and /dev/stdin is UNIX-wide understood
(which is a strict superset of the former), so we are safe on that front.
Signed-off-by: Jonathon Jongsma <jjongsma@xxxxxxxxxx>
---
libvirt.spec.in | 2 +
m4/virt-external-programs.m4 | 3 +
src/conf/virnodedeviceobj.c | 34 +++++
src/conf/virnodedeviceobj.h | 3 +
src/libvirt_private.syms | 1 +
src/node_device/node_device_driver.c | 203 +++++++++++++++++++++++++++
src/node_device/node_device_driver.h | 6 +
7 files changed, 252 insertions(+)
diff --git a/libvirt.spec.in b/libvirt.spec.in
index 262e66f3cc..2b3a4d2e71 100644
--- a/libvirt.spec.in
+++ b/libvirt.spec.in
@@ -522,6 +522,8 @@ Requires: libvirt-daemon = %{version}-%{release}
Requires: libvirt-libs = %{version}-%{release}
# needed for device enumeration
Requires: systemd >= 185
+# For managing persistent mediated devices
+Requires: mdevctl
%description daemon-driver-nodedev
The nodedev driver plugin for the libvirtd daemon, providing
diff --git a/m4/virt-external-programs.m4 b/m4/virt-external-programs.m4
index 9046e3bf07..bd3cb1f757 100644
--- a/m4/virt-external-programs.m4
+++ b/m4/virt-external-programs.m4
@@ -65,6 +65,7 @@ AC_DEFUN([LIBVIRT_CHECK_EXTERNAL_PROGRAMS], [
AC_PATH_PROG([OVSVSCTL], [ovs-vsctl], [ovs-vsctl], [$LIBVIRT_SBIN_PATH])
AC_PATH_PROG([SCRUB], [scrub], [scrub], [$LIBVIRT_SBIN_PATH])
AC_PATH_PROG([ADDR2LINE], [addr2line], [addr2line], [$LIBVIRT_SBIN_PATH])
+ AC_PATH_PROG([MDEVCTL], [mdevctl], [mdevctl], [$LIBVIRT_SBIN_PATH])
This will need to look slightly different - see 07/10.
AC_DEFINE_UNQUOTED([DMIDECODE], ["$DMIDECODE"],
[Location or name of the dmidecode program])
@@ -88,6 +89,8 @@ AC_DEFUN([LIBVIRT_CHECK_EXTERNAL_PROGRAMS], [
[Location or name of the scrub program (for wiping algorithms)])
AC_DEFINE_UNQUOTED([ADDR2LINE], ["$ADDR2LINE"],
[Location of addr2line program])
+ AC_DEFINE_UNQUOTED([MDEVCTL], ["$MDEVCTL"],
+ [Location or name of the mdevctl program])
AC_PATH_PROG([IP_PATH], [ip], [/sbin/ip], [$LIBVIRT_SBIN_PATH])
AC_DEFINE_UNQUOTED([IP_PATH], ["$IP_PATH"], [path to ip binary])
diff --git a/src/conf/virnodedeviceobj.c b/src/conf/virnodedeviceobj.c
index 3a34a324ca..fd20d5f9e2 100644
--- a/src/conf/virnodedeviceobj.c
+++ b/src/conf/virnodedeviceobj.c
@@ -399,6 +399,40 @@ virNodeDeviceObjListFindSCSIHostByWWNs(virNodeDeviceObjListPtr devs,
&data);
}
+static int
+virNodeDeviceObjListFindMediatedDeviceByUUIDCallback(const void *payload,
+ const void *name G_GNUC_UNUSED,
+ const void *opaque G_GNUC_UNUSED)
+{
+ virNodeDeviceObjPtr obj = (virNodeDeviceObjPtr) payload;
+ const char *uuid = (const char *) opaque;
+ virNodeDevCapsDefPtr cap;
+ int want = 0;
+
+ virObjectLock(obj);
+
+ for (cap = obj->def->caps; cap != NULL; cap = cap->next) {
+ if (cap->data.type == VIR_NODE_DEV_CAP_MDEV) {
+ if (STREQ(cap->data.mdev.uuid, uuid)) {
+ want = 1;
+ break;
+ }
+ }
+ }
+
+ virObjectUnlock(obj);
+ return want;
+}
+
+
+virNodeDeviceObjPtr
+virNodeDeviceObjListFindMediatedDeviceByUUID(virNodeDeviceObjListPtr devs,
+ const char *uuid)
+{
+ return virNodeDeviceObjListSearch(devs,
+ virNodeDeviceObjListFindMediatedDeviceByUUIDCallback,
+ uuid);
+}
static void
virNodeDeviceObjListDispose(void *obj)
diff --git a/src/conf/virnodedeviceobj.h b/src/conf/virnodedeviceobj.h
index c9df8dedab..6efdb23d36 100644
--- a/src/conf/virnodedeviceobj.h
+++ b/src/conf/virnodedeviceobj.h
@@ -118,3 +118,6 @@ virNodeDeviceObjListExport(virConnectPtr conn,
void
virNodeDeviceObjSetSkipUpdateCaps(virNodeDeviceObjPtr obj,
bool skipUpdateCaps);
+virNodeDeviceObjPtr
+virNodeDeviceObjListFindMediatedDeviceByUUID(virNodeDeviceObjListPtr devs,
+ const char *uuid);
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index b8e6f058c3..532169d93d 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1178,6 +1178,7 @@ virNodeDeviceObjListAssignDef;
virNodeDeviceObjListExport;
virNodeDeviceObjListFindByName;
virNodeDeviceObjListFindBySysfsPath;
+virNodeDeviceObjListFindMediatedDeviceByUUID;
virNodeDeviceObjListFindSCSIHostByWWNs;
virNodeDeviceObjListFree;
virNodeDeviceObjListGetNames;
diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c
index 629d4bcf91..dbc7eb4d1e 100644
--- a/src/node_device/node_device_driver.c
+++ b/src/node_device/node_device_driver.c
@@ -30,6 +30,7 @@
#include "datatypes.h"
#include "viralloc.h"
#include "virfile.h"
+#include "virjson.h"
#include "virstring.h"
#include "node_device_conf.h"
#include "node_device_event.h"
@@ -40,6 +41,7 @@
#include "viraccessapicheck.h"
#include "virnetdev.h"
#include "virutil.h"
+#include "vircommand.h"
#define VIR_FROM_THIS VIR_FROM_NODEDEV
@@ -304,6 +306,30 @@ nodeDeviceLookupSCSIHostByWWN(virConnectPtr conn,
return device;
}
+static virNodeDevicePtr
+nodeDeviceLookupMediatedDeviceByUUID(virConnectPtr conn,
+ const char *uuid,
+ unsigned int flags)
+{
+ virNodeDeviceObjPtr obj = NULL;
+ virNodeDeviceDefPtr def;
+ virNodeDevicePtr device = NULL;
+
+ virCheckFlags(0, NULL);
+
+ if (!(obj = virNodeDeviceObjListFindMediatedDeviceByUUID(driver->devs,
+ uuid)))
+ return NULL;
+
+ def = virNodeDeviceObjGetDef(obj);
+
+ if ((device = virGetNodeDevice(conn, def->name)))
+ device->parentName = g_strdup(def->parent);
+
+ virNodeDeviceObjEndAPI(&obj);
+ return device;
+}
+
char *
nodeDeviceGetXMLDesc(virNodeDevicePtr device,
@@ -492,6 +518,25 @@ nodeDeviceFindNewDevice(virConnectPtr conn,
}
+static virNodeDevicePtr
+nodeDeviceFindNewMediatedDeviceFunc(virConnectPtr conn,
+ const void *opaque)
+{
+ const char *uuid = opaque;
+ return nodeDeviceLookupMediatedDeviceByUUID(conn, uuid, 0);
+}
+
+
+static virNodeDevicePtr
+nodeDeviceFindNewMediatedDevice(virConnectPtr conn,
+ const char *mdev_uuid)
+{
+ return nodeDeviceFindNewDevice(conn,
+ nodeDeviceFindNewMediatedDeviceFunc,
+ mdev_uuid);
+}
+
+
typedef struct _NewSCSIHostFuncData NewSCSIHostFuncData;
struct _NewSCSIHostFuncData
{
@@ -534,6 +579,162 @@ nodeDeviceHasCapability(virNodeDeviceDefPtr def, virNodeDevCapType type)
}
+/* format a json string that provides configuration information about this mdev
+ * to the mdevctl utility */
+static int
+nodeDeviceDefToMdevctlConfig(virNodeDeviceDefPtr def, char **buf)
+{
+ size_t i;
+ virNodeDevCapMdevPtr mdev = &def->caps->data.mdev;
+ g_autoptr(virJSONValue) json = virJSONValueNewObject();
+
+ if (virJSONValueObjectAppendString(json, "mdev_type", mdev->type) < 0)
+ return -1;
+ if (virJSONValueObjectAppendString(json, "start", "manual") < 0)
+ return -1;
+ if (mdev->attributes) {
+ g_autoptr(virJSONValue) attributes = virJSONValueNewArray();
+ for (i = 0; i < mdev->nattributes; i++) {
+ virMediatedDeviceAttrPtr attr = mdev->attributes[i];
+ g_autoptr(virJSONValue) jsonattr = virJSONValueNewObject();
+
+ if (virJSONValueObjectAppendString(jsonattr, attr->name, attr->value) < 0)
+ return -1;
+ if (virJSONValueArrayAppend(attributes, g_steal_pointer(&jsonattr)) < 0)
+ return -1;
+ }
+ if (virJSONValueObjectAppend(json, "attrs", g_steal_pointer(&attributes)) < 0)
+ return -1;
+ }
+
+ *buf = virJSONValueToString(json, false);
+ if (!*buf)
+ return -1;
+
+ return 0;
+}
+
+
+static char *
+nodeDeviceFindAddressByName(const char *name)
+{
+ virNodeDeviceDefPtr def = NULL;
+ virNodeDevCapsDefPtr caps = NULL;
+ char *pci_addr = NULL;
+ virNodeDeviceObjPtr dev = virNodeDeviceObjListFindByName(driver->devs, name);
+
+ if (!dev) {
+ virReportError(VIR_ERR_NO_NODE_DEVICE,
+ _("could not find device '%s'"), name);
+ return NULL;
+ }
+
+ def = virNodeDeviceObjGetDef(dev);
+ for (caps = def->caps; caps != NULL; caps = caps->next) {
+ if (caps->data.type == VIR_NODE_DEV_CAP_PCI_DEV) {
+ virPCIDeviceAddress addr = {
+ .domain = caps->data.pci_dev.domain,
+ .bus = caps->data.pci_dev.bus,
+ .slot = caps->data.pci_dev.slot,
+ .function = caps->data.pci_dev.function
+ };
+
+ pci_addr = virPCIDeviceAddressAsString(&addr);
+ break;
+ }
+ }
+
+ virNodeDeviceObjEndAPI(&dev);
+
+ return pci_addr;
+}
+
+
+virCommandPtr
+nodeDeviceGetMdevctlStartCommand(virNodeDeviceDefPtr def,
+ bool persist,
+ char **uuid_out)
+{
+ virCommandPtr cmd;
+ const char *subcommand;
+ g_autofree char *json = NULL;
+ g_autofree char *mdevctl = virFindFileInPath(MDEVCTL);
+ g_autofree char *parent_pci = nodeDeviceFindAddressByName(def->parent);
+
+ if (!mdevctl)
+ return NULL;
This virFindFileInPath() and @mdevctl variable aren't necessary.
virCommandRun() will call virFindFileInPath() under the hood (see
v6.4.0-66-gf603b99ad9). And also, if the function fails, it does so
silently. And this doesn't report error neither.
+
+ if (!parent_pci) {
+ virReportError(VIR_ERR_NO_NODE_DEVICE,
+ _("unable to find PCI address for parent device '%s'"), def->parent);
+ return NULL;
+ }
+
+ if (nodeDeviceDefToMdevctlConfig(def, &json) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("couldn't convert node device def to mdevctl JSON"));
+ return NULL;
+ }
+
+ if (persist)
+ subcommand = "define";
+ else
+ subcommand = "start";
+
+ cmd = virCommandNewArgList(mdevctl, subcommand,
+ "-p", parent_pci,
+ "--jsonfile", "/dev/stdin",
+ NULL);
+
+ virCommandSetInputBuffer(cmd, json);
+ virCommandSetOutputBuffer(cmd, uuid_out);
+
+ return cmd;
+}
+
+static int
+virMdevctlStart(virNodeDeviceDefPtr def, char **uuid)
+{
+ int status;
+ g_autoptr(virCommand) cmd = nodeDeviceGetMdevctlStartCommand(def, false,
+ uuid);
+ if (!cmd)
+ return -1;
+
+ /* an auto-generated uuid is returned via stdout if no uuid is specified in
+ * the mdevctl args */
+ if (virCommandRun(cmd, &status) < 0 || status != 0)
+ return -1;
+
+ /* remove newline */
+ *uuid = g_strstrip(*uuid);
+
+ return 0;
+}
+
+
+static virNodeDevicePtr
+nodeDeviceCreateXMLMdev(virConnectPtr conn,
+ virNodeDeviceDefPtr def)
+{
+ g_autofree char *uuid = NULL;
+
+ if (!def->parent) {
+ virReportError(VIR_ERR_XML_ERROR, "%s",
+ _("cannot create a mediated device without a parent"));
+ return NULL;
+ }
+
+ if (virMdevctlStart(def, &uuid) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Unable to start mediated device"));
+ return NULL;
+ }
+
+ return nodeDeviceFindNewMediatedDevice(conn, uuid);
+}
+
+
virNodeDevicePtr
nodeDeviceCreateXML(virConnectPtr conn,
const char *xmlDesc,
@@ -578,6 +779,8 @@ nodeDeviceCreateXML(virConnectPtr conn,
_("no node device for '%s' with matching "
"wwnn '%s' and wwpn '%s'"),
def->name, wwnn, wwpn);
+ } else if (nodeDeviceHasCapability(def, VIR_NODE_DEV_CAP_MDEV)) {
+ device = nodeDeviceCreateXMLMdev(conn, def);
} else {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("Unsupported device type"));
diff --git a/src/node_device/node_device_driver.h b/src/node_device/node_device_driver.h
index eae5e2cb17..576f75375f 100644
--- a/src/node_device/node_device_driver.h
+++ b/src/node_device/node_device_driver.h
@@ -24,6 +24,7 @@
#include "internal.h"
#include "driver.h"
#include "virnodedeviceobj.h"
+#include "vircommand.h"
#define LINUX_NEW_DEVICE_WAIT_TIME 60
@@ -116,3 +117,8 @@ nodeConnectNodeDeviceEventRegisterAny(virConnectPtr conn,
int
nodeConnectNodeDeviceEventDeregisterAny(virConnectPtr conn,
int callbackID);
+
+virCommandPtr
+nodeDeviceGetMdevctlStartCommand(virNodeDeviceDefPtr def,
+ bool persist,
+ char **uuid_out);
