vol: break callbacks when needsCallback is set

The needsCallback vol header field indicates that a volume has been
altered by a non-fileserver program somehow, and that callbacks for
the volume should be broken. So, when we attach a volume that has this
flag set, break callbacks if we can. If we are not the fileserver,
tell the fileserver over FSSYNC to break callbacks if we can.

Change-Id: I1b1a4042f0381e8291a407b54ce9478877dacdca
Reviewed-on: http://gerrit.openafs.org/2211
Tested-by: Andrew Deason <adeason@sinenomine.net>
Tested-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>

diff --git a/src/vol/volume.c b/src/vol/volume.c
index 65b4004..ffd76aa 100644 (file)
--- a/src/vol/volume.c
+++ b/src/vol/volume.c
@@ -2447,13 +2447,6 @@ VAttachVolumeByName_r(Error * ec, char *partition, char *name, int mode)
            goto done;
        }
 #endif
-       V_needsCallback(vp) = 0;
-#ifdef notdef
-       if (VInit >= 2 && V_BreakVolumeCallbacks) {
-           Log("VAttachVolume: Volume %u was changed externally; breaking callbacks\n", V_id(vp));
-           (*V_BreakVolumeCallbacks) (V_id(vp));
-       }
-#endif
        VUpdateVolume_r(ec, vp, 0);
        if (*ec) {
            Log("VAttachVolume: Error updating volume\n");
@@ -2601,7 +2594,6 @@ VAttachVolumeByVp_r(Error * ec, Volume * vp, int mode)
        goto done;
     }
 
-    V_needsCallback(vp) = 0;
     VUpdateVolume_r(ec, vp, 0);
     if (*ec) {
        Log("VAttachVolume: Error updating volume %u\n", vp->hashid);
@@ -3271,6 +3263,52 @@ attach2(Error * ec, VolId volumeId, char *path, struct DiskPartition64 *partp,
     }
 #endif /* BITMAP_LATER */
 
+    if (VInit >= 2 && V_needsCallback(vp)) {
+       if (V_BreakVolumeCallbacks) {
+           Log("VAttachVolume: Volume %lu was changed externally; breaking callbacks\n",
+               afs_printable_uint32_lu(V_id(vp)));
+           V_needsCallback(vp) = 0;
+           VOL_UNLOCK;
+           (*V_BreakVolumeCallbacks) (V_id(vp));
+           VOL_LOCK;
+
+           VUpdateVolume_r(ec, vp, 0);
+       }
+#ifdef FSSYNC_BUILD_CLIENT
+       else if (VCanUseFSSYNC()) {
+           afs_int32 fsync_code;
+
+           V_needsCallback(vp) = 0;
+           VOL_UNLOCK;
+           fsync_code = FSYNC_VolOp(V_id(vp), NULL, FSYNC_VOL_BREAKCBKS, FSYNC_WHATEVER, NULL);
+           VOL_LOCK;
+
+           if (fsync_code) {
+               V_needsCallback(vp) = 1;
+               Log("Error trying to tell the fileserver to break callbacks for "
+                   "changed volume %lu; error code %ld\n",
+                   afs_printable_uint32_lu(V_id(vp)),
+                   afs_printable_int32_ld(fsync_code));
+           } else {
+               VUpdateVolume_r(ec, vp, 0);
+           }
+       }
+#endif /* FSSYNC_BUILD_CLIENT */
+
+       if (*ec) {
+           Log("VAttachVolume: error %d clearing needsCallback on volume "
+               "%lu; needs salvage\n", (int)*ec,
+               afs_printable_uint32_lu(V_id(vp)));
+#ifdef AFS_DEMAND_ATTACH_FS
+           VRequestSalvage_r(ec, vp, SALVSYNC_ERROR, VOL_SALVAGE_INVALIDATE_HEADER);
+           vp->nUsers = 0;
+#else /* !AFS_DEMAND_ATTACH_FS */
+           *ec = VSALVAGE;
+#endif /* !AFS_DEMAND_ATTACh_FS */
+           goto error;
+       }
+    }
+
     if (programType == fileServer) {
        if (vp->specialStatus)
            vp->specialStatus = 0;