From f72ba6aded6093d34d5e8a1666a844ec2b0ee5eb Mon Sep 17 00:00:00 2001

From: Vojtech Trefny <vtrefny@redhat.com>

Date: Tue, 18 Apr 2023 12:05:35 +0200

Subject: [PATCH] lvm: Add support for starting and stopping VG locking

---

 docs/libblockdev-sections.txt |  2 ++

 src/lib/plugin_apis/lvm.api   | 27 +++++++++++++++++++

 src/plugins/lvm-dbus.c        | 49 ++++++++++++++++++++++++++++++++++-

 src/plugins/lvm.c             | 41 +++++++++++++++++++++++++++++

 src/plugins/lvm.h             |  3 +++

 tests/lvm_dbus_tests.py       | 33 +++++++++++++++++++++++

 tests/lvm_test.py             | 32 +++++++++++++++++++++++

 7 files changed, 186 insertions(+), 1 deletion(-)

diff --git a/docs/libblockdev-sections.txt b/docs/libblockdev-sections.txt

index 540e2b96..08ea309c 100644

--- a/docs/libblockdev-sections.txt

+++ b/docs/libblockdev-sections.txt

@@ -286,6 +286,8 @@ bd_lvm_vgactivate

 bd_lvm_vgdeactivate

 bd_lvm_vgextend

 bd_lvm_vgreduce

+bd_lvm_vglock_start

+bd_lvm_vglock_stop

 bd_lvm_vginfo

 bd_lvm_vgs

 bd_lvm_lvorigin

diff --git a/src/lib/plugin_apis/lvm.api b/src/lib/plugin_apis/lvm.api

index 640eee49..1343fbdb 100644

--- a/src/lib/plugin_apis/lvm.api

+++ b/src/lib/plugin_apis/lvm.api

@@ -603,6 +603,7 @@ typedef enum {

     BD_LVM_TECH_GLOB_CONF,

     BD_LVM_TECH_VDO,

     BD_LVM_TECH_DEVICES,

+    BD_LVM_TECH_SHARED,

 } BDLVMTech;

 typedef enum {

@@ -943,6 +944,32 @@ gboolean bd_lvm_vgextend (const gchar *vg_name, const gchar *device, const BDExt

  */

 gboolean bd_lvm_vgreduce (const gchar *vg_name, const gchar *device, const BDExtraArg **extra, GError **error);

+/**

+ * bd_lvm_vglock_start:

+ * @vg_name: a shared VG to start the lockspace in lvmlockd

+ * @extra: (nullable) (array zero-terminated=1): extra options for the vgchange command

+ *                                               (just passed to LVM as is)

+ * @error: (out): place to store error (if any)

+ *

+ * Returns: whether the lock was successfully started for @vg_name or not

+ *

+ * Tech category: %BD_LVM_TECH_SHARED-%BD_LVM_TECH_MODE_MODIFY

+ */

+gboolean bd_lvm_vglock_start (const gchar *vg_name, const BDExtraArg **extra, GError **error);

+

+/**

+ * bd_lvm_vglock_stop:

+ * @vg_name: a shared VG to stop the lockspace in lvmlockd

+ * @extra: (nullable) (array zero-terminated=1): extra options for the vgchange command

+ *                                               (just passed to LVM as is)

+ * @error: (out): place to store error (if any)

+ *

+ * Returns: whether the lock was successfully stopped for @vg_name or not

+ *

+ * Tech category: %BD_LVM_TECH_SHARED-%BD_LVM_TECH_MODE_MODIFY

+ */

+gboolean bd_lvm_vglock_stop (const gchar *vg_name, const BDExtraArg **extra, GError **error);

+

 /**

  * bd_lvm_vginfo:

  * @vg_name: a VG to get information about

diff --git a/src/plugins/lvm-dbus.c b/src/plugins/lvm-dbus.c

index 46e09833..a129d884 100644

--- a/src/plugins/lvm-dbus.c

+++ b/src/plugins/lvm-dbus.c

@@ -1872,10 +1872,57 @@ gboolean bd_lvm_vgreduce (const gchar *vg_name, const gchar *device, const BDExt

     return ((*error) == NULL);

 }

+gboolean _vglock_start_stop (const gchar *vg_name, gboolean start, const BDExtraArg **extra, GError **error) {

+    GVariantBuilder builder;

+    GVariant *params = NULL;

+

+    g_variant_builder_init (&builder, G_VARIANT_TYPE_DICTIONARY);

+    if (start)

+        g_variant_builder_add (&builder, "{sv}", "--lockstart", g_variant_new ("s", ""));

+    else

+        g_variant_builder_add (&builder, "{sv}", "--lockstop", g_variant_new ("s", ""));

+    params = g_variant_builder_end (&builder);

+    g_variant_builder_clear (&builder);

+

+    call_lvm_obj_method_sync (vg_name, VG_INTF, "Change", NULL, params, extra, TRUE, error);

+

+    return ((*error) == NULL);

+}

+

+/**

+ * bd_lvm_vglock_start:

+ * @vg_name: a shared VG to start the lockspace in lvmlockd

+ * @extra: (nullable) (array zero-terminated=1): extra options for the vgchange command

+ *                                               (just passed to LVM as is)

+ * @error: (out): place to store error (if any)

+ *

+ * Returns: whether the lock was successfully started for @vg_name or not

+ *

+ * Tech category: %BD_LVM_TECH_BASIC-%BD_LVM_TECH_MODE_MODIFY

+ */

+gboolean bd_lvm_vglock_start (const gchar *vg_name, const BDExtraArg **extra, GError **error) {

+    return _vglock_start_stop (vg_name, TRUE, extra, error);

+}

+

+/**

+ * bd_lvm_vglock_stop:

+ * @vg_name: a shared VG to stop the lockspace in lvmlockd

+ * @extra: (nullable) (array zero-terminated=1): extra options for the vgchange command

+ *                                               (just passed to LVM as is)

+ * @error: (out): place to store error (if any)

+ *

+ * Returns: whether the lock was successfully stopped for @vg_name or not

+ *

+ * Tech category: %BD_LVM_TECH_BASIC-%BD_LVM_TECH_MODE_MODIFY

+ */

+gboolean bd_lvm_vglock_stop (const gchar *vg_name, const BDExtraArg **extra, GError **error) {

+    return _vglock_start_stop (vg_name, FALSE, extra, error);

+}

+

 /**

  * bd_lvm_vginfo:

  * @vg_name: a VG to get information about

- * @error: (out): place to store error (if any)

+ * @error: (out) (optional): place to store error (if any)

  *

  * Returns: (transfer full): information about the @vg_name VG or %NULL in case

  * of error (the @error) gets populated in those cases)

diff --git a/src/plugins/lvm.c b/src/plugins/lvm.c

index 0db3bf4a..b0a71224 100644

--- a/src/plugins/lvm.c

+++ b/src/plugins/lvm.c

@@ -1341,6 +1341,47 @@ gboolean bd_lvm_vgreduce (const gchar *vg_name, const gchar *device, const BDExt

     return call_lvm_and_report_error (args, extra, TRUE, error);

 }

+gboolean _vglock_start_stop (const gchar *vg_name, gboolean start, const BDExtraArg **extra, GError **error) {

+    const gchar *args[4] = {"vgchange", NULL, vg_name, NULL};

+

+    if (start)

+        args[1] = "--lockstart";

+    else

+        args[1] = "--lockstop";

+

+    return call_lvm_and_report_error (args, extra, TRUE, error);

+}

+

+/**

+ * bd_lvm_vglock_start:

+ * @vg_name: a shared VG to start the lockspace in lvmlockd

+ * @extra: (nullable) (array zero-terminated=1): extra options for the vgchange command

+ *                                               (just passed to LVM as is)

+ * @error: (out): place to store error (if any)

+ *

+ * Returns: whether the lock was successfully started for @vg_name or not

+ *

+ * Tech category: %BD_LVM_TECH_SHARED-%BD_LVM_TECH_MODE_MODIFY

+ */

+gboolean bd_lvm_vglock_start (const gchar *vg_name, const BDExtraArg **extra, GError **error) {

+    return _vglock_start_stop (vg_name, TRUE, extra, error);

+}

+

+/**

+ * bd_lvm_vglock_stop:

+ * @vg_name: a shared VG to stop the lockspace in lvmlockd

+ * @extra: (nullable) (array zero-terminated=1): extra options for the vgchange command

+ *                                               (just passed to LVM as is)

+ * @error: (out): place to store error (if any)

+ *

+ * Returns: whether the lock was successfully stopped for @vg_name or not

+ *

+ * Tech category: %BD_LVM_TECH_SHARED-%BD_LVM_TECH_MODE_MODIFY

+ */

+gboolean bd_lvm_vglock_stop (const gchar *vg_name, const BDExtraArg **extra, GError **error) {

+    return _vglock_start_stop (vg_name, FALSE, extra, error);

+}

+

 /**

  * bd_lvm_vginfo:

  * @vg_name: a VG to get information about

diff --git a/src/plugins/lvm.h b/src/plugins/lvm.h

index c85c043d..2e47b06f 100644

--- a/src/plugins/lvm.h

+++ b/src/plugins/lvm.h

@@ -218,6 +218,7 @@ typedef enum {

     BD_LVM_TECH_GLOB_CONF,

     BD_LVM_TECH_VDO,

     BD_LVM_TECH_DEVICES,

+    BD_LVM_TECH_SHARED,

 } BDLVMTech;

 typedef enum {

@@ -268,6 +269,8 @@ gboolean bd_lvm_vgactivate (const gchar *vg_name, const BDExtraArg **extra, GErr

 gboolean bd_lvm_vgdeactivate (const gchar *vg_name, const BDExtraArg **extra, GError **error);

 gboolean bd_lvm_vgextend (const gchar *vg_name, const gchar *device, const BDExtraArg **extra, GError **error);

 gboolean bd_lvm_vgreduce (const gchar *vg_name, const gchar *device, const BDExtraArg **extra, GError **error);

+gboolean bd_lvm_vglock_start (const gchar *vg_name, const BDExtraArg **extra, GError **error);

+gboolean bd_lvm_vglock_stop (const gchar *vg_name, const BDExtraArg **extra, GError **error);

 BDLVMVGdata* bd_lvm_vginfo (const gchar *vg_name, GError **error);

 BDLVMVGdata** bd_lvm_vgs (GError **error);

diff --git a/tests/lvm_dbus_tests.py b/tests/lvm_dbus_tests.py

index a821636e..bc8b3052 100644

--- a/tests/lvm_dbus_tests.py

+++ b/tests/lvm_dbus_tests.py

@@ -655,6 +655,39 @@ class LvmTestVGs(LvmPVVGTestCase):

         succ = BlockDev.lvm_pvremove(self.loop_dev, None)

         self.assertTrue(succ)

+@unittest.skipUnless(lvm_dbus_running, "LVM DBus not running")

+class LvmTestVGLocking(LvmPVVGTestCase):

+    @tag_test(TestTags.UNSAFE)

+    def test_vglock_stop_start(self):

+        """Verify that it is possible to start and stop locking on a VG"""

+

+        # better not do anything if lvmlockd is running, shared VGs have

+        # a tendency to wreak havoc on your system if you look at them wrong

+        ret, _out, _err = run_command("systemctl is-active lvmlockd")

+        if ret == 0:

+            self.skipTest("lvmlockd is running, skipping")

+

+        _ret, out, _err = run_command("lvm config 'global/use_lvmlockd'")

+        if "use_lvmlockd=0" not in out:

+            self.skipTest("lvmlockd is enabled, skipping")

+

+        succ = BlockDev.lvm_pvcreate(self.loop_dev, 0, 0, None)

+        self.assertTrue(succ)

+

+        succ = BlockDev.lvm_pvcreate(self.loop_dev2, 0, 0, None)

+        self.assertTrue(succ)

+

+        succ = BlockDev.lvm_vgcreate("testVG", [self.loop_dev, self.loop_dev2], 0, None)

+        self.assertTrue(succ)

+

+        # this actually doesn't "test" anything, the commands will just say lvmlockd is not

+        # running and return 0, but that's good enough for us

+        succ = BlockDev.lvm_vglock_start("testVG")

+        self.assertTrue(succ)

+

+        succ = BlockDev.lvm_vglock_stop("testVG")

+        self.assertTrue(succ)

+

 @unittest.skipUnless(lvm_dbus_running, "LVM DBus not running")

 class LvmPVVGLVTestCase(LvmPVVGTestCase):

     def _clean_up(self):

diff --git a/tests/lvm_test.py b/tests/lvm_test.py

index 63f43afb..d517001b 100644

--- a/tests/lvm_test.py

+++ b/tests/lvm_test.py

@@ -632,6 +632,38 @@ class LvmTestVGs(LvmPVVGTestCase):

         succ = BlockDev.lvm_pvremove(self.loop_dev, None)

         self.assertTrue(succ)

+class LvmTestVGLocking(LvmPVVGTestCase):

+    @tag_test(TestTags.UNSAFE)

+    def test_vglock_stop_start(self):

+        """Verify that it is possible to start and stop locking on a VG"""

+

+        # better not do anything if lvmlockd is running, shared VGs have

+        # a tendency to wreak havoc on your system if you look at them wrong

+        ret, _out, _err = run_command("systemctl is-active lvmlockd")

+        if ret == 0:

+            self.skipTest("lvmlockd is running, skipping")

+

+        _ret, out, _err = run_command("lvm config 'global/use_lvmlockd'")

+        if "use_lvmlockd=0" not in out:

+            self.skipTest("lvmlockd is enabled, skipping")

+

+        succ = BlockDev.lvm_pvcreate(self.loop_dev, 0, 0, None)

+        self.assertTrue(succ)

+

+        succ = BlockDev.lvm_pvcreate(self.loop_dev2, 0, 0, None)

+        self.assertTrue(succ)

+

+        succ = BlockDev.lvm_vgcreate("testVG", [self.loop_dev, self.loop_dev2], 0, None)

+        self.assertTrue(succ)

+

+        # this actually doesn't "test" anything, the commands will just say lvmlockd is not

+        # running and return 0, but that's good enough for us

+        succ = BlockDev.lvm_vglock_start("testVG")

+        self.assertTrue(succ)

+

+        succ = BlockDev.lvm_vglock_stop("testVG")

+        self.assertTrue(succ)

+

 class LvmPVVGLVTestCase(LvmPVVGTestCase):

     def _clean_up(self):

         try:

-- 

2.41.0