From af9bf10ff9d8a6f0ae9b6d898138144bf7dcd161 Mon Sep 17 00:00:00 2001
Message-Id: <af9bf10ff9d8a6f0ae9b6d898138144bf7dcd161@dist-git>
From: Pavel Hrdina <phrdina@redhat.com>
Date: Mon, 1 Jul 2019 17:07:18 +0200
Subject: [PATCH] vircgroup: introduce virCgroupV2DetectPlacement
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If the placement was copied from parent or set to absolute path
there is nothing to do, otherwise set the placement based on
process placement from /proc/self/cgroup or /proc/{pid}/cgroup.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
(cherry picked from commit 1efcf202e777d32600e90f3176e0357053341533)

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1689297

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Message-Id: <7fcc9d25385c40df5531e5b7171338a624d0c4fb.1561993100.git.phrdina@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
---
 src/util/vircgroupv2.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/src/util/vircgroupv2.c b/src/util/vircgroupv2.c
index 19a9ba38f8..fb1aa2de0a 100644
--- a/src/util/vircgroupv2.c
+++ b/src/util/vircgroupv2.c
@@ -181,6 +181,31 @@ virCgroupV2DetectMounts(virCgroupPtr group,
 }
 
 
+static int
+virCgroupV2DetectPlacement(virCgroupPtr group,
+                           const char *path,
+                           const char *controllers ATTRIBUTE_UNUSED,
+                           const char *selfpath)
+{
+    if (group->unified.placement)
+        return 0;
+
+    /*
+     * selfpath == "/" + path="" -> "/"
+     * selfpath == "/libvirt.service" + path == "" -> "/libvirt.service"
+     * selfpath == "/libvirt.service" + path == "foo" -> "/libvirt.service/foo"
+     */
+    if (virAsprintf(&group->unified.placement,
+                    "%s%s%s", selfpath,
+                    (STREQ(selfpath, "/") ||
+                     STREQ(path, "") ? "" : "/"),
+                    path) < 0)
+        return -1;
+
+    return 0;
+}
+
+
 virCgroupBackend virCgroupV2Backend = {
     .type = VIR_CGROUP_BACKEND_TYPE_V2,
 
@@ -189,6 +214,7 @@ virCgroupBackend virCgroupV2Backend = {
     .copyMounts = virCgroupV2CopyMounts,
     .copyPlacement = virCgroupV2CopyPlacement,
     .detectMounts = virCgroupV2DetectMounts,
+    .detectPlacement = virCgroupV2DetectPlacement,
 };
 
 
-- 
2.22.0