From f835b834d7922bed1ccda35885e42ab7c3f4a70f Mon Sep 17 00:00:00 2001

Message-Id: <f835b834d7922bed1ccda35885e42ab7c3f4a70f@dist-git>

From: Pavel Hrdina <phrdina@redhat.com>

Date: Fri, 19 Feb 2021 13:33:58 +0100

Subject: [PATCH] vircgroup: introduce virCgroupV1Exists and virCgroupV2Exists

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This will check if the cgroup actually exists on the system.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

(cherry picked from commit badc2bcc7398d8c0a739998a80411ddebf129512)

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1798463

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>

Message-Id: <14297ed923f0f23cc52506e61e637c8f45e331ee.1613737828.git.phrdina@redhat.com>

Reviewed-by: Ján Tomko <jtomko@redhat.com>

---

 src/util/vircgroupbackend.h |  4 ++++

 src/util/vircgroupv1.c      | 27 +++++++++++++++++++++++++++

 src/util/vircgroupv2.c      | 15 +++++++++++++++

 3 files changed, 46 insertions(+)

diff --git a/src/util/vircgroupbackend.h b/src/util/vircgroupbackend.h

index ac7b3ae517..dabc7bd4b4 100644

--- a/src/util/vircgroupbackend.h

+++ b/src/util/vircgroupbackend.h

@@ -115,6 +115,9 @@ typedef int

                                const char *key,

                                char **path);

+typedef bool

+(*virCgroupExistsCB)(virCgroupPtr group);

+

 typedef int

 (*virCgroupMakeGroupCB)(virCgroupPtr parent,

                         virCgroupPtr group,

@@ -378,6 +381,7 @@ struct _virCgroupBackend {

     virCgroupGetAnyControllerCB getAnyController;

     virCgroupPathOfControllerCB pathOfController;

     virCgroupMakeGroupCB makeGroup;

+    virCgroupExistsCB exists;

     virCgroupRemoveCB remove;

     virCgroupAddTaskCB addTask;

     virCgroupHasEmptyTasksCB hasEmptyTasks;

diff --git a/src/util/vircgroupv1.c b/src/util/vircgroupv1.c

index eb2b611cee..57d617cb69 100644

--- a/src/util/vircgroupv1.c

+++ b/src/util/vircgroupv1.c

@@ -670,6 +670,32 @@ virCgroupV1MakeGroup(virCgroupPtr parent,

 }

+static bool

+virCgroupV1Exists(virCgroupPtr group)

+{

+    size_t i;

+

+    for (i = 0; i < VIR_CGROUP_CONTROLLER_LAST; i++) {

+        g_autofree char *path = NULL;

+

+        if (i == VIR_CGROUP_CONTROLLER_SYSTEMD)

+            continue;

+

+        if (!group->legacy[i].mountPoint)

+            continue;

+

+        if (virCgroupV1PathOfController(group, i, "", &path) < 0)

+            return false;

+

+        if (!virFileExists(path)) {

+            return false;

+        }

+    }

+

+    return true;

+}

+

+

 static int

 virCgroupV1Remove(virCgroupPtr group)

 {

@@ -2136,6 +2162,7 @@ virCgroupBackend virCgroupV1Backend = {

     .getAnyController = virCgroupV1GetAnyController,

     .pathOfController = virCgroupV1PathOfController,

     .makeGroup = virCgroupV1MakeGroup,

+    .exists = virCgroupV1Exists,

     .remove = virCgroupV1Remove,

     .addTask = virCgroupV1AddTask,

     .hasEmptyTasks = virCgroupV1HasEmptyTasks,

diff --git a/src/util/vircgroupv2.c b/src/util/vircgroupv2.c

index 5e19ed8332..d15e2354cf 100644

--- a/src/util/vircgroupv2.c

+++ b/src/util/vircgroupv2.c

@@ -493,6 +493,20 @@ virCgroupV2MakeGroup(virCgroupPtr parent,

 }

+static bool

+virCgroupV2Exists(virCgroupPtr group)

+{

+    g_autofree char *path = NULL;

+    int controller;

+

+    controller = virCgroupV2GetAnyController(group);

+    if (virCgroupV2PathOfController(group, controller, "", &path) < 0)

+        return false;

+

+    return virFileExists(path);

+}

+

+

 static int

 virCgroupV2Remove(virCgroupPtr group)

 {

@@ -1886,6 +1900,7 @@ virCgroupBackend virCgroupV2Backend = {

     .getAnyController = virCgroupV2GetAnyController,

     .pathOfController = virCgroupV2PathOfController,

     .makeGroup = virCgroupV2MakeGroup,

+    .exists = virCgroupV2Exists,

     .remove = virCgroupV2Remove,

     .addTask = virCgroupV2AddTask,

     .hasEmptyTasks = virCgroupV2HasEmptyTasks,

-- 

2.30.0