[libvirt] [PATCH 6/6] Widening API change - accept empty path for virDomainBlockStats

[Thorsten Behrens]

And provide domain summary stats in that case, for lxc backend.
Use case is a container domain using passthrough bind mounts of the
host filesystem, which is a common case for lxc.
---
 src/libvirt.c              |  1 -
 src/lxc/lxc_driver.c       | 10 ++++++++++
 src/qemu/qemu_driver.c     |  2 ++
 src/remote/remote_driver.c |  2 ++
 src/test/test_driver.c     |  2 ++
 src/xen/xen_driver.c       |  2 ++
 6 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/libvirt.c b/src/libvirt.c
index 87a4d46..14ffca0 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -7804,7 +7804,6 @@ virDomainBlockStats(virDomainPtr dom, const char *disk,
     virResetLastError();
 
     virCheckDomainReturn(dom, -1);
-    virCheckNonNullArgGoto(disk, error);
     virCheckNonNullArgGoto(stats, error);
     if (size > sizeof(stats2)) {
         virReportInvalidArg(size,
diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
index 1d2a457..fba9c12 100644
--- a/src/lxc/lxc_driver.c
+++ b/src/lxc/lxc_driver.c
@@ -2044,6 +2044,16 @@ lxcDomainBlockStats(virDomainPtr dom,
         goto cleanup;
     }
 
+    if (!path || !*path) {
+        /* empty/NULL path - return entire domain blkstats instead */
+        ret = virCgroupGetBlkioIoServiced(priv->cgroup,
+                                          &stats->rd_bytes,
+                                          &stats->wr_bytes,
+                                          &stats->rd_req,
+                                          &stats->wr_req);
+        goto cleanup;
+    }
+
     if ((idx = virDomainDiskIndexByName(vm->def, path, false)) < 0) {
         virReportError(VIR_ERR_INVALID_ARG,
                        _("invalid path: %s"), path);
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 2d92873..4dcf12b 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -9021,6 +9021,8 @@ qemuDomainBlockStats(virDomainPtr dom,
     virDomainDiskDefPtr disk = NULL;
     qemuDomainObjPrivatePtr priv;
 
+    virCheckNonNullArgReturn(path, -1);
+
     if (!(vm = qemuDomObjFromDomain(dom)))
         goto cleanup;
 
diff --git a/src/remote/remote_driver.c b/src/remote/remote_driver.c
index da9c1c9..160bdd4 100644
--- a/src/remote/remote_driver.c
+++ b/src/remote/remote_driver.c
@@ -1713,6 +1713,8 @@ remoteDomainBlockStatsFlags(virDomainPtr domain,
     remote_domain_block_stats_flags_ret ret;
     struct private_data *priv = domain->conn->privateData;
 
+    virCheckNonNullArgReturn(path, -1);
+
     remoteDriverLock(priv);
 
     make_nonnull_domain(&args.dom, domain);
diff --git a/src/test/test_driver.c b/src/test/test_driver.c
index b724f82..7c637bb 100644
--- a/src/test/test_driver.c
+++ b/src/test/test_driver.c
@@ -3362,6 +3362,8 @@ static int testDomainBlockStats(virDomainPtr domain,
     unsigned long long statbase;
     int ret = -1;
 
+    virCheckNonNullArgReturn(path, -1);
+
     testDriverLock(privconn);
     privdom = virDomainObjListFindByName(privconn->domains,
                                          domain->name);
diff --git a/src/xen/xen_driver.c b/src/xen/xen_driver.c
index c45d10f..2b9ac21 100644
--- a/src/xen/xen_driver.c
+++ b/src/xen/xen_driver.c
@@ -2217,6 +2217,8 @@ xenUnifiedDomainBlockStats(virDomainPtr dom, const char *path,
     virDomainDefPtr def = NULL;
     int ret = -1;
 
+    virCheckNonNullArgReturn(path, -1);
+
     if (!(def = xenGetDomainDefForDom(dom)))
         goto cleanup;
 
-- 
1.8.4