salvager: Do not fork for single VG salvage

Currently we always fork a child in the salvager in order to salvage a
volume group. I believe this is in order to protect SEGV, exit(), etc
in one salvage operation from preventing salvaging anything else. When
salvaging a single volume group, though, there appears to be little
benefit.

In addition, we need to keep the VG salvaging code in the same process
as the cleanup code for single-volume salvages, so we can know which
volumes were deleted by SalvageVolumeGroup, so we know which volumes
to bring back online. So, do not fork for the singleVolumeNumber case.

Note that for DAFS, we already never fork for the entire salvage
operation when salvaging an individual volume group. So, this is
effectively a non-DAFS-only change.

Reviewed-on: http://gerrit.openafs.org/6787
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit 46e85dd4682a3273e15bbf96c4d5492087555cab)

Change-Id: I545e9ad8d54ad63dbe8e221dfc6947446135cbb7
Reviewed-on: http://gerrit.openafs.org/9462
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>

diff --git a/src/vol/vol-salvage.c b/src/vol/vol-salvage.c
index 91e5cb12386262b0bf67eeb5b484bce551e0aaf5..fb8859b27c80aa312728e03cae2325868325cefa 100644 (file)
--- a/src/vol/vol-salvage.c
+++ b/src/vol/vol-salvage.c
@@ -906,6 +906,16 @@ SalvageFileSys1(struct DiskPartition64 *partP, VolumeId singleVolumeNumber)
        goto retry;
     }
 
+    if (singleVolumeNumber) {
+       /* If we delete a volume during the salvage, we indicate as such by
+        * setting the volsummary->deleted field. We need to know if we
+        * deleted a volume or not in order to know which volumes to bring
+        * back online after the salvage. If we fork, we will lose this
+        * information, since volsummary->deleted will not get set in the
+        * parent. So, don't fork. */
+       canfork = 0;
+    }
+
     for (i = j = 0, vsp = salvinfo->volumeSummaryp, esp = vsp + salvinfo->nVolumes;
         i < salvinfo->nVolumesInInodeFile; i = j) {
        VolumeId rwvid = salvinfo->inodeSummary[i].RWvolumeId;