[libvirt] [PATCH] qemu_domain: Drop namespace check from top level functions

[Michal Privoznik]

In some cases we are checking if the mount namespace is enabled
at two places: one is at the beginning of exported function (e.g.
qemuDomainNamespaceSetupDisk()) and the other is at the beginning
of qemuDomainNamespaceMknodPaths() which is called from the
former function anyway. Then we have some other functions which
rely on the later check solely.

In order to compensate for possibly needles function call,
qemuDomainNamespaceMknodPaths() returns early if @npaths is zero.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_domain.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 5329899b13..15325aa4c1 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -12428,7 +12428,8 @@ qemuDomainNamespaceMknodPaths(virDomainObjPtr vm,
     int ret = -1;
     size_t i;
 
-    if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
+    if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT) ||
+        !npaths)
         return 0;
 
     cfg = virQEMUDriverGetConfig(driver);
@@ -12521,9 +12522,6 @@ qemuDomainNamespaceSetupDisk(virDomainObjPtr vm,
     char *dmPath = NULL;
     int ret = -1;
 
-    if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
-        return 0;
-
     for (next = src; virStorageSourceIsBacking(next); next = next->backingStore) {
         if (virStorageSourceIsEmpty(next) ||
             !virStorageSourceIsLocalStorage(next)) {
@@ -12574,9 +12572,6 @@ qemuDomainNamespaceSetupHostdev(virDomainObjPtr vm,
     char **paths = NULL;
     size_t i, npaths = 0;
 
-    if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
-        return 0;
-
     if (qemuDomainGetHostdevPath(NULL, hostdev, false, &npaths, &paths, NULL) < 0)
         goto cleanup;
 
@@ -12600,9 +12595,6 @@ qemuDomainNamespaceTeardownHostdev(virDomainObjPtr vm,
     char **paths = NULL;
     size_t i, npaths = 0;
 
-    if (!qemuDomainNamespaceEnabled(vm, QEMU_DOMAIN_NS_MOUNT))
-        return 0;
-
     if (qemuDomainGetHostdevPath(vm->def, hostdev, true,
                                  &npaths, &paths, NULL) < 0)
         goto cleanup;
-- 
2.16.4