dasalvager: unlink fsstate.dat when standalone

If the DAFS salvager is running in a standalone mode, unlink the
fileserver's fsstate.dat file if any volumes change. Otherwise, volume
data could have changed and the fileserver will retain callback
promises for the data in those volumes until it tries to attach the
volume. This way, callbacks are broken via callback state
reinitialization.

A better solution is to record which volumes have changed, and the
fileserver can break callbacks for them on startup. But this at least
eliminates a regression from non-DAFS behavior.

Change-Id: Ie443e7d43705c3015d21bd3cad1b1e05c88562be
Reviewed-on: http://gerrit.openafs.org/4638
Tested-by: Andrew Deason <adeason@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>

diff --git a/src/vol/vol-salvage.c b/src/vol/vol-salvage.c
index 24f59f2..d92bd5b 100644 (file)
--- a/src/vol/vol-salvage.c
+++ b/src/vol/vol-salvage.c
@@ -4133,22 +4133,41 @@ SalvageVolume(struct SalvInfo *salvinfo, struct InodeSummary *rwIsp, IHandle_t *
            afs_printable_uint32_lu(vid));
     }
 
+    if (!Testing && salvinfo->VolumeChanged) {
 #ifdef FSSYNC_BUILD_CLIENT
-    if (!Testing && salvinfo->VolumeChanged && salvinfo->useFSYNC) {
-       afs_int32 fsync_code;
-
-       fsync_code = FSYNC_VolOp(vid, NULL, FSYNC_VOL_BREAKCBKS, FSYNC_SALVAGE, NULL);
-       if (fsync_code) {
-           Log("Error trying to tell the fileserver to break callbacks for "
-               "changed volume %lu; error code %ld\n",
-               afs_printable_uint32_lu(vid),
-               afs_printable_int32_ld(fsync_code));
-       } else {
-           salvinfo->VolumeChanged = 0;
+       if (salvinfo->useFSYNC) {
+           afs_int32 fsync_code;
+
+           fsync_code = FSYNC_VolOp(vid, NULL, FSYNC_VOL_BREAKCBKS, FSYNC_SALVAGE, NULL);
+           if (fsync_code) {
+               Log("Error trying to tell the fileserver to break callbacks for "
+                   "changed volume %lu; error code %ld\n",
+                   afs_printable_uint32_lu(vid),
+                   afs_printable_int32_ld(fsync_code));
+           } else {
+               salvinfo->VolumeChanged = 0;
+           }
        }
-    }
 #endif /* FSSYNC_BUILD_CLIENT */
 
+#if defined(AFS_DEMAND_ATTACH_FS) || defined(AFS_DEMAND_ATTACH_UTIL)
+       if (!salvinfo->useFSYNC) {
+           /* A volume's contents have changed, but the fileserver will not
+            * break callbacks on the volume until it tries to load the vol
+            * header. So, to reduce the amount of time a client could have
+            * stale data, remove fsstate.dat, so the fileserver will init
+            * callback state with all clients. This is a very coarse hammer,
+            * and in the future we should just record which volumes have
+            * changed. */
+           code = unlink(AFSDIR_SERVER_FSSTATE_FILEPATH);
+           if (code && errno != ENOENT) {
+               Log("Error %d when trying to unlink FS state file %s\n", errno,
+                   AFSDIR_SERVER_FSSTATE_FILEPATH);
+           }
+       }
+#endif
+    }
+
     /* Turn off the inUse bit; the volume's been salvaged! */
     volHeader.inUse = 0;       /* clear flag indicating inUse@last crash */
     volHeader.needsSalvaged = 0;       /* clear 'damaged' flag */