From 5b3562a9f0ea7ab11212639753cdf9064394df92 Mon Sep 17 00:00:00 2001

From: Katy Feng <fkaty@vmware.com>

Date: Tue, 22 Aug 2023 11:11:42 -0700

Subject: [PATCH] Provide alternate method to allow (expected) pre-frozen

 filesystems when taking a quiesced snapshot.

RH-Author: Ani Sinha <None>

RH-MergeRequest: 29: Provide alternate method to allow (expected) pre-frozen filesystems when taking a quiesced snapshot.

RH-Bugzilla: 2226921

RH-Acked-by: Vitaly Kuznetsov <vkuznets@redhat.com>

RH-Commit: [1/1] 5582a9588692896258f3711c278e97127e748f67

Effective with open-vm-tools 12.2.0, Linux quiesced snapshots will fail if

any filesystem(s) have been prefrozen by other than the vmtoolsd process.

This has been done to assure that filesystems are inactive while the

snapshots are being taken. Some existing prefreeze scripts may be freezing

some filesystem(s). In these cases, the vmtoolsd process must be informed of

anticipated pre-frozen filesystems by providing an "excludedFileSystem" list in

the [vmbackup] section of the tools.conf file.

This change provides a new switch in the tools.conf file to allow pre-frozen

filesystems to be encountered and accepted when doing a quiesced snapshot

operation. With the default value of "false", the "ignoreFrozenFileSystems"

can be configured with a setting of "true" to notify the quiesced snapshot

operation that pre-frozen filesystems are allowed.

(cherry picked from commit 60c3a80ddc2b400366ed05169e16a6bed6501da2)

Signed-off-by: Ani Sinha <anisinha@redhat.com>

 Conflicts:

	open-vm-tools/services/plugins/vix/foundryToolsDaemon.c

	open-vm-tools/services/plugins/vmbackup/syncDriverOps.c

	open-vm-tools/tools.conf

---

 open-vm-tools/lib/include/syncDriver.h        |  5 ++--

 open-vm-tools/lib/syncDriver/nullDriver.c     | 10 ++++---

 open-vm-tools/lib/syncDriver/syncDriverInt.h  | 14 ++++++----

 .../lib/syncDriver/syncDriverLinux.c          | 25 +++++++++++++----

 .../lib/syncDriver/syncDriverPosix.c          |  7 +++--

 open-vm-tools/lib/syncDriver/vmSyncDriver.c   | 10 ++++---

 .../services/plugins/vix/foundryToolsDaemon.c | 16 +++++++++--

 .../services/plugins/vmbackup/stateMachine.c  |  8 ++++--

 .../services/plugins/vmbackup/syncDriverOps.c |  5 ++--

 .../services/plugins/vmbackup/vmBackupInt.h   | 19 ++++++++-----

 open-vm-tools/tools.conf                      | 28 +++++++++++++++++++

 11 files changed, 109 insertions(+), 38 deletions(-)

diff --git a/open-vm-tools/lib/include/syncDriver.h b/open-vm-tools/lib/include/syncDriver.h

index 20712f66..8ef229d4 100644

--- a/open-vm-tools/lib/include/syncDriver.h

+++ b/open-vm-tools/lib/include/syncDriver.h

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2005-2018 VMware, Inc. All rights reserved.

+ * Copyright (c) 2005-2018, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -51,7 +51,8 @@ typedef enum {

 Bool SyncDriver_Init(void);

 Bool SyncDriver_Freeze(const char *drives, Bool enableNullDriver,

                        SyncDriverHandle *handle,

-                       const char *excludedFileSystems);

+                       const char *excludedFileSystems,

+                       Bool ignoreFrozenFS);

 Bool SyncDriver_Thaw(const SyncDriverHandle handle);

 SyncDriverStatus SyncDriver_QueryStatus(const SyncDriverHandle handle,

                                         int32 timeout);

diff --git a/open-vm-tools/lib/syncDriver/nullDriver.c b/open-vm-tools/lib/syncDriver/nullDriver.c

index 5e19e208..be96222a 100644

--- a/open-vm-tools/lib/syncDriver/nullDriver.c

+++ b/open-vm-tools/lib/syncDriver/nullDriver.c

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2011-2016 VMware, Inc. All rights reserved.

+ * Copyright (c) 2011-2016, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -54,8 +54,9 @@ NullDriverClose(SyncDriverHandle handle)

  *

  * Calls sync().

  *

- * @param[in]  paths     Unused.

- * @param[out] handle    Where to store the operation handle.

+ * @param[in]  paths            Unused.

+ * @param[out] handle           Where to store the operation handle.

+ * @param[in]  ignoreFrozenFS   Unused.

  *

  * @return A SyncDriverErr.

  *

@@ -64,7 +65,8 @@ NullDriverClose(SyncDriverHandle handle)

 SyncDriverErr

 NullDriver_Freeze(const GSList *paths,

-                  SyncDriverHandle *handle)

+                  SyncDriverHandle *handle,

+                  Bool ignoreFrozenFS)

 {

    /*

     * This is more of a "let's at least do something" than something that

diff --git a/open-vm-tools/lib/syncDriver/syncDriverInt.h b/open-vm-tools/lib/syncDriver/syncDriverInt.h

index 04f37bf2..a5706298 100644

--- a/open-vm-tools/lib/syncDriver/syncDriverInt.h

+++ b/open-vm-tools/lib/syncDriver/syncDriverInt.h

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2011-2017 VMware, Inc. All rights reserved.

+ * Copyright (c) 2011-2017, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -41,7 +41,8 @@ typedef enum {

 } SyncDriverErr;

 typedef SyncDriverErr (*SyncFreezeFn)(const GSList *paths,

-                                      SyncDriverHandle *handle);

+                                      SyncDriverHandle *handle,

+                                      Bool ignoreFrozenFs);

 typedef struct SyncHandle {

    SyncDriverErr (*thaw)(const SyncDriverHandle handle);

@@ -55,15 +56,18 @@ typedef struct SyncHandle {

 #if defined(__linux__)

 SyncDriverErr

 LinuxDriver_Freeze(const GSList *userPaths,

-                   SyncDriverHandle *handle);

+                   SyncDriverHandle *handle,

+                   Bool ignoreFrozenFs);

 SyncDriverErr

 VmSync_Freeze(const GSList *userPaths,

-              SyncDriverHandle *handle);

+              SyncDriverHandle *handle,

+              Bool ignoreFrozenFs);

 SyncDriverErr

 NullDriver_Freeze(const GSList *userPaths,

-                  SyncDriverHandle *handle);

+                  SyncDriverHandle *handle,

+                  Bool ignoreFrozenFs);

 #endif

 #endif

diff --git a/open-vm-tools/lib/syncDriver/syncDriverLinux.c b/open-vm-tools/lib/syncDriver/syncDriverLinux.c

index 6d9a3568..4581098e 100644

--- a/open-vm-tools/lib/syncDriver/syncDriverLinux.c

+++ b/open-vm-tools/lib/syncDriver/syncDriverLinux.c

@@ -199,8 +199,9 @@ LinuxFiGetAttr(const SyncDriverHandle handle,   // IN (ignored)

  * slow when guest is performing significant IO. Therefore, caller should

  * consider running this function in a separate thread.

  *

- * @param[in]  paths    List of paths to freeze.

- * @param[out] handle   Handle to use for thawing.

+ * @param[in]  paths           List of paths to freeze.

+ * @param[out] handle          Handle to use for thawing.

+ * @param[in]  ignoreFrozenFS  Switch to allow EBUSY error.

  *

  * @return A SyncDriverErr.

  *

@@ -209,7 +210,8 @@ LinuxFiGetAttr(const SyncDriverHandle handle,   // IN (ignored)

 SyncDriverErr

 LinuxDriver_Freeze(const GSList *paths,

-                   SyncDriverHandle *handle)

+                   SyncDriverHandle *handle,

+                   Bool ignoreFrozenFS)

 {

    ssize_t count = 0;

    Bool first = TRUE;

@@ -324,9 +326,12 @@ LinuxDriver_Freeze(const GSList *paths,

           * Previously, an EBUSY error was ignored, assuming that we may try

           * to freeze the same superblock more than once depending on the

           * OS configuration (e.g., usage of bind mounts).

-          * Using the filesystem Id to check if this is a filesystem that we

-          * have seen previously and will ignore this FD only if that is

-          * the case.  Log a warning otherwise since the quiesced snapshot

+          * Use the filesystem Id to check if this filesystem has been

+          * handled before and, if so, ignore it.

+          * Alternatively, allow (ignore) the EBUSY if the

+          * "ignoreFrozenFileSystems" switch inside "vmbackup" section of

+          * tools.conf file is TRUE.

+          * Otherwise, log a warning as the quiesced snapshot

           * attempt will fail.

           */

          if (ioctlerr == EBUSY) {

@@ -339,6 +344,14 @@ LinuxDriver_Freeze(const GSList *paths,

                 */

                Debug(LGPFX "skipping path '%s' - previously frozen", path);

                continue;

+            } else if (ignoreFrozenFS) {

+               /*

+                * Ignores the EBUSY error if the FS has been frozen by another

+                * process and the 'ignoreFrozenFileSystems' setting is

+                * turned on in tools.conf file.

+                */

+               Debug(LGPFX "Ignoring the frozen filesystem '%s'",path);

+               continue;

             }

             /*

              * It appears that this FS has been locked or frozen by another

diff --git a/open-vm-tools/lib/syncDriver/syncDriverPosix.c b/open-vm-tools/lib/syncDriver/syncDriverPosix.c

index 7b6132ba..27369639 100644

--- a/open-vm-tools/lib/syncDriver/syncDriverPosix.c

+++ b/open-vm-tools/lib/syncDriver/syncDriverPosix.c

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2005-2019 VMware, Inc. All rights reserved.

+ * Copyright (c) 2005-2019, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -456,7 +456,8 @@ Bool

 SyncDriver_Freeze(const char *userPaths,              // IN

                   Bool enableNullDriver,              // IN

                   SyncDriverHandle *handle,           // OUT

-                  const char *excludedFileSystems)    // IN

+                  const char *excludedFileSystems,    // IN

+                  Bool ignoreFrozenFS)                // IN

 {

    GSList *paths = NULL;

    SyncDriverErr err = SD_UNAVAILABLE;

@@ -517,7 +518,7 @@ SyncDriver_Freeze(const char *userPaths,              // IN

          continue;

       }

 #endif

-      err = freezeFn(paths, handle);

+      err = freezeFn(paths, handle, ignoreFrozenFS);

    }

    /*

diff --git a/open-vm-tools/lib/syncDriver/vmSyncDriver.c b/open-vm-tools/lib/syncDriver/vmSyncDriver.c

index 2bd0e886..a0d4a315 100644

--- a/open-vm-tools/lib/syncDriver/vmSyncDriver.c

+++ b/open-vm-tools/lib/syncDriver/vmSyncDriver.c

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2011-2016 VMware, Inc. All rights reserved.

+ * Copyright (c) 2011-2016, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -91,8 +91,9 @@ VmSyncClose(SyncDriverHandle handle)

  * Opens a description to the driver's proc node, and if successful, send an

  * ioctl to freeze the requested filesystems.

  *

- * @param[in]  paths    List of paths to freeze.

- * @param[out] handle   Where to store the handle to use for thawing.

+ * @param[in]  paths          List of paths to freeze.

+ * @param[out] handle         Where to store the handle to use for thawing.

+ * @param[in]  ignoreFrozenFS Unused.

  *

  * @return A SyncDriverErr.

  *

@@ -101,7 +102,8 @@ VmSyncClose(SyncDriverHandle handle)

 SyncDriverErr

 VmSync_Freeze(const GSList *paths,

-              SyncDriverHandle *handle)

+              SyncDriverHandle *handle,

+              Bool ignoreFrozenFS)

 {

    int file;

    Bool first = TRUE;

diff --git a/open-vm-tools/services/plugins/vix/foundryToolsDaemon.c b/open-vm-tools/services/plugins/vix/foundryToolsDaemon.c

index 99a40a8c..437c90fd 100644

--- a/open-vm-tools/services/plugins/vix/foundryToolsDaemon.c

+++ b/open-vm-tools/services/plugins/vix/foundryToolsDaemon.c

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2003-2019 VMware, Inc. All rights reserved.

+ * Copyright (c) 2003-2021, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -544,6 +544,8 @@ ToolsDaemonTcloSyncDriverFreeze(RpcInData *data)

    GKeyFile *confDictRef = ctx->config;

    Bool enableNullDriver;

    GSource *timer;

+   char *excludedFileSystems;

+   Bool ignoreFrozenFS;

    /*

     * Parse the arguments

@@ -576,14 +578,22 @@ ToolsDaemonTcloSyncDriverFreeze(RpcInData *data)

       goto abort;

    }

-   enableNullDriver = VixTools_ConfigGetBoolean(confDictRef,

+   enableNullDriver = VMTools_ConfigGetBoolean(confDictRef,

                                                 "vmbackup",

                                                 "enableNullDriver",

                                                 FALSE);

+   excludedFileSystems = VMTools_ConfigGetString(confDictRef,

+                                                  "vmbackup",

+                                                  "excludedFileSystems",

+                                                  NULL);

+   ignoreFrozenFS = VMTools_ConfigGetBoolean(confDictRef,

+                                             "vmbackup",

+                                             "ignoreFrozenFileSystems",

+                                             FALSE);

    /* Perform the actual freeze. */

    if (!SyncDriver_Freeze(driveList, enableNullDriver, &gSyncDriverHandle,

-                          NULL) ||

+                          excludedFileSystems, ignoreFrozenFS) ||

        SyncDriver_QueryStatus(gSyncDriverHandle, INFINITE) != SYNCDRIVER_IDLE) {

       g_warning("%s: Failed to Freeze drives '%s'\n",

                 __FUNCTION__, driveList);

diff --git a/open-vm-tools/services/plugins/vmbackup/stateMachine.c b/open-vm-tools/services/plugins/vmbackup/stateMachine.c

index 6b422869..9e6f0541 100644

--- a/open-vm-tools/services/plugins/vmbackup/stateMachine.c

+++ b/open-vm-tools/services/plugins/vmbackup/stateMachine.c

@@ -1024,9 +1024,13 @@ VmBackupStartCommon(RpcInData *data,

 #if defined(__linux__)

    gBackupState->excludedFileSystems =

          VMBACKUP_CONFIG_GET_STR(ctx->config, "excludedFileSystems", NULL);

-   g_debug("Using excludedFileSystems = \"%s\"\n",

+   gBackupState->ignoreFrozenFS =

+       VMBACKUP_CONFIG_GET_BOOL(ctx->config, "ignoreFrozenFileSystems", FALSE);

+

+   g_debug("Using excludedFileSystems = \"%s\", ignoreFrozenFileSystems = %d\n",

            (gBackupState->excludedFileSystems != NULL) ?

-            gBackupState->excludedFileSystems : "(null)");

+            gBackupState->excludedFileSystems : "(null)",

+           gBackupState->ignoreFrozenFS);

 #endif

    g_debug("Quiescing volumes: %s",

            (gBackupState->volumes) ? gBackupState->volumes : "(null)");

diff --git a/open-vm-tools/services/plugins/vmbackup/syncDriverOps.c b/open-vm-tools/services/plugins/vmbackup/syncDriverOps.c

index 4245feba..d8b635f1 100644

--- a/open-vm-tools/services/plugins/vmbackup/syncDriverOps.c

+++ b/open-vm-tools/services/plugins/vmbackup/syncDriverOps.c

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2007-2019 VMware, Inc. All rights reserved.

+ * Copyright (C) 2007-2019, 2021, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -276,7 +276,8 @@ VmBackupNewDriverOp(VmBackupState *state,       // IN

                                      useNullDriverPrefs ?

                                         state->enableNullDriver : FALSE,

                                      op->syncHandle,

-                                     state->excludedFileSystems);

+                                     state->excludedFileSystems,

+                                     state->ignoreFrozenFS);

          break;

       case OP_THAW:

          op->manifest = SyncNewManifest(state, *op->syncHandle);

diff --git a/open-vm-tools/services/plugins/vmbackup/vmBackupInt.h b/open-vm-tools/services/plugins/vmbackup/vmBackupInt.h

index 0c912174..65e2e552 100644

--- a/open-vm-tools/services/plugins/vmbackup/vmBackupInt.h

+++ b/open-vm-tools/services/plugins/vmbackup/vmBackupInt.h

@@ -1,5 +1,5 @@

 /*********************************************************

- * Copyright (C) 2008-2019 VMware, Inc. All rights reserved.

+ * Copyright (c) 2008-2019, 2023 VMware, Inc. All rights reserved.

  *

  * This program is free software; you can redistribute it and/or modify it

  * under the terms of the GNU Lesser General Public License as published

@@ -100,18 +100,22 @@ struct VmBackupSyncCompleter;

  * Don't modify the fields directly - rather, use VmBackup_SetCurrentOp,

  * which does most of the handling needed by users of the state machine.

  *

- * NOTE: The thread for freeze operation modifies currentOp in BackupState

- *       which is also accessed by the AsyncCallback driving the state

- *       machine (run by main thread). Also, gcc might generate two

- *       instructions for writing a 64-bit value. Therefore, protect the

- *       access to currentOp and related fields using opLock mutex.

+ * NOTE 1: The thread for freeze operation modifies currentOp in BackupState

+ *         which is also accessed by the AsyncCallback driving the state

+ *         machine (run by main thread). Also, gcc might generate two

+ *         instructions for writing a 64-bit value. Therefore, protect the

+ *         access to currentOp and related fields using opLock mutex.

+ *

+ * NOTE 2: Only used by Linux guests, ignored on Windows guests and is

+ *         initialized to "false" when the VmBackupState is initialized

+ *         at the start of a backup operation.

  */

 typedef struct VmBackupState {

    ToolsAppCtx   *ctx;

    VmBackupOp    *currentOp;

    const char    *currentOpName;

-   GMutex         opLock;          // See note above

+   GMutex         opLock;          // See note 1 above

    char          *volumes;

    char          *snapshots;

    guint          pollPeriod;

@@ -127,6 +131,7 @@ typedef struct VmBackupState {

    Bool           allowHWProvider;

    Bool           execScripts;

    Bool           enableNullDriver;

+   Bool           ignoreFrozenFS;   // See note 2 above

    Bool           needsPriv;

    gchar         *scriptArg;

    guint          timeout;

diff --git a/open-vm-tools/tools.conf b/open-vm-tools/tools.conf

index 7c99b4dc..57ad9271 100644

--- a/open-vm-tools/tools.conf

+++ b/open-vm-tools/tools.conf

@@ -270,11 +270,39 @@

 # including '/'

 #excludedFileSystems=

+

+# Linux:

+# It is possible that filesystems are being frozen in pre-freeze scripts

+# to control the order in which those specific filesystems are to be frozen.

+# The vmtoolsd process must be informed of all such filesystems with the help

+# of "excludedFileSystems" setting of tools.conf.

+#

+# A temporary workaround is available (starting from 12.3.0) for admins to allow

+# quiesceing operation to succeed until the "excludedFileSystems" list

+# is configured.

+#

+# If another process thaws the file system while a quiescing operation

+# operation is ongoing, the snapshot may be compromised. Once the

+# "excludedFileSystems" list is configured this setting MUST be unset (or set

+# to false).

+#

+# The value of ignoreFrozenFileSystems is a true or false; the default is

+# false.

+#

+# Set to true to ignore pre-frozen file systems during the quiescing operation.

+#

+# ignoreFrozenFileSystems is Linux only (Not supported on Windows).

+#ignoreFrozenFileSystems=false

+

 # Whether to execute scripts on quiescing.

 # Scripts are executed from /etc/vmware-tools/backupScripts.d on Linux and

 # %installpath%\backupScripts.d on Windows, and the legacy scripts

 # "c:\windows\pre-freeze-script.bat"

 # "c:\windows\post-thaw-script.bat"

+# execScripts specifies whether to execute scripts as part of the quiescing

+# operation. Scripts are executed from the scripts directory along with the

+# legacy scripts.

+

 #

 # Linux:

 # "/usr/sbin/pre-freeze-script"

-- 

2.41.0