viced: VNOVOL on deleted volumes

When the volserver deletes a volume, the fileserver should respond to
future access to that volume with VNOVOL and not VOFFLINE, since the
volume doesn't exist anymore. Do this in DAFS via a new state,
VOL_STATE_DELETED, and in non-DAFS by just setting specialStatus to
VNOVOL.

In the future we should also make sure the vp's for deleted volumes
get freed after a couple of hours, but not yet.

Change-Id: I6dec3e0a5e9e54f6ad09fad9f2355b513cce3bf6
Reviewed-on: http://gerrit.openafs.org/2533
Tested-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>

src/vol/fssync-debug.c

@@ -554,6 +554,7 @@ vol_state_to_string(VolState state)
 	ENUMCASE(VOL_STATE_VNODE_CLOSE);
 	ENUMCASE(VOL_STATE_VNODE_RELEASE);
 	ENUMCASE(VOL_STATE_VLRU_ADD);
+	ENUMCASE(VOL_STATE_DELETED);
 	ENUMCASE(VOL_STATE_FREED);
     default:
 	return "**UNKNOWN**";

src/vol/fssync-server.c

@@ -1185,10 +1185,8 @@ static afs_int32
 FSYNC_com_VolDone(FSSYNC_VolOp_command * vcom, SYNC_response * res)
 {
     afs_int32 code = SYNC_FAILED;
-#ifdef AFS_DEMAND_ATTACH_FS
     Error error;
     Volume * vp;
-#endif
 
     if (SYNC_verifyProtocolString(vcom->vop->partName, sizeof(vcom->vop->partName))) {
 	res->hdr.reason = SYNC_REASON_MALFORMED_PACKET;
@@ -1201,19 +1199,33 @@ FSYNC_com_VolDone(FSSYNC_VolOp_command * vcom, SYNC_response * res)
     if (vcom->v)
 	vcom->v->volumeID = 0;
 
-#ifdef AFS_DEMAND_ATTACH_FS
     vp = VLookupVolume_r(&error, vcom->vop->volume, NULL);
     if (vp) {
 	if (FSYNC_partMatch(vcom, vp, 1)) {
+#ifdef AFS_DEMAND_ATTACH_FS
 	    if ((V_attachState(vp) == VOL_STATE_UNATTACHED) ||
 		(V_attachState(vp) == VOL_STATE_PREATTACHED)) {
-		VChangeState_r(vp, VOL_STATE_UNATTACHED);
+
+		/* Change state to DELETED, not UNATTACHED, so clients get
+		 * a VNOVOL error when they try to access from now on. */
+
+		VChangeState_r(vp, VOL_STATE_DELETED);
 		VDeregisterVolOp_r(vp);
+
+		/* Someday we should free the vp, too, after about 2 hours,
+		 * possibly by putting the vp back on the VLRU. */
+
 		code = SYNC_OK;
 	    } else {
 		code = SYNC_DENIED;
 		res->hdr.reason = FSYNC_BAD_STATE;
 	    }
+#else /* AFS_DEMAND_ATTACH_FS */
+	    if (!vp->specialStatus) {
+		vp->specialStatus = VNOVOL;
+	    }
+	    code = SYNC_OK;
+#endif /* !AFS_DEMAND_ATTACH_FS */
 	} else {
 	    code = SYNC_OK; /* XXX is this really a good idea? */
 	    res->hdr.reason = FSYNC_WRONG_PART;
@@ -1221,7 +1233,6 @@ FSYNC_com_VolDone(FSSYNC_VolOp_command * vcom, SYNC_response * res)
     } else {
 	res->hdr.reason = FSYNC_UNKNOWN_VOLID;
     }
-#endif
 
  done:
     return code;

src/vol/volume.c

@@ -1780,6 +1780,7 @@ ShutdownVolumeWalk_r(struct DiskPartition64 * dp, int pass,
 	case 0:
 	    if ((V_attachState(vp) != VOL_STATE_UNATTACHED) &&
 		(V_attachState(vp) != VOL_STATE_ERROR) &&
+		(V_attachState(vp) != VOL_STATE_DELETED) &&
 		(V_attachState(vp) != VOL_STATE_PREATTACHED)) {
 		break;
 	    }
@@ -1835,6 +1836,7 @@ VShutdownVolume_r(Volume * vp)
     case VOL_STATE_ERROR:
 	VChangeState_r(vp, VOL_STATE_UNATTACHED);
     case VOL_STATE_UNATTACHED:
+    case VOL_STATE_DELETED:
 	break;
     case VOL_STATE_GOING_OFFLINE:
     case VOL_STATE_SHUTTING_DOWN:
@@ -2133,7 +2135,8 @@ VPreAttachVolumeByVp_r(Error * ec,
 
     /* check to see if pre-attach already happened */
     if (vp && 
-	(V_attachState(vp) != VOL_STATE_UNATTACHED) && 
+	(V_attachState(vp) != VOL_STATE_UNATTACHED) &&
+	(V_attachState(vp) != VOL_STATE_DELETED) &&
 	(V_attachState(vp) != VOL_STATE_PREATTACHED) &&
 	!VIsErrorState(V_attachState(vp))) {
 	/*
@@ -2285,6 +2288,7 @@ VAttachVolumeByName_r(Error * ec, char *partition, char *name, int mode)
 	     *   - GOING_OFFLINE
 	     *   - SALVAGING
 	     *   - ERROR
+	     *   - DELETED
 	     */
 
 	    if (vp->specialStatus == VBUSY)
@@ -2317,6 +2321,7 @@ VAttachVolumeByName_r(Error * ec, char *partition, char *name, int mode)
 	/* pre-attach volume if it hasn't been done yet */
 	if (!vp || 
 	    (V_attachState(vp) == VOL_STATE_UNATTACHED) ||
+	    (V_attachState(vp) == VOL_STATE_DELETED) ||
 	    (V_attachState(vp) == VOL_STATE_ERROR)) {
 	    svp = vp;
 	    vp = VPreAttachVolumeByVp_r(ec, partp, vp, volumeId);
@@ -2561,6 +2566,7 @@ VAttachVolumeByVp_r(Error * ec, Volume * vp, int mode)
     /* pre-attach volume if it hasn't been done yet */
     if (!vp || 
 	(V_attachState(vp) == VOL_STATE_UNATTACHED) ||
+	(V_attachState(vp) == VOL_STATE_DELETED) ||
 	(V_attachState(vp) == VOL_STATE_ERROR)) {
 	nvp = VPreAttachVolumeByVp_r(ec, partp, vp, volumeId);
 	if (*ec) {
@@ -3699,13 +3705,15 @@ GetVolume(Error * ec, Error * client_ec, VolId volumeId, Volume * hint, int nowa
 	}
 
 	/*
-	 * short circuit with VOFFLINE in the following circumstances:
+	 * short circuit with VOFFLINE for VOL_STATE_UNATTACHED and
-	 *
+	 *                    VNOVOL   for VOL_STATE_DELETED
-	 *   - VOL_STATE_UNATTACHED
 	 */
-       if (V_attachState(vp) == VOL_STATE_UNATTACHED) {
+       if ((V_attachState(vp) == VOL_STATE_UNATTACHED) ||
+           (V_attachState(vp) == VOL_STATE_DELETED)) {
 	   if (vp->specialStatus) {
 	       *ec = vp->specialStatus;
+	   } else if (V_attachState(vp) == VOL_STATE_DELETED) {
+	       *ec = VNOVOL;
 	   } else {
 	       *ec = VOFFLINE;
 	   }
@@ -4556,7 +4564,8 @@ VCheckOffline(register Volume * vp)
 	assert((V_attachState(vp) != VOL_STATE_ATTACHED) &&
 	       (V_attachState(vp) != VOL_STATE_FREED) &&
 	       (V_attachState(vp) != VOL_STATE_PREATTACHED) &&
-	       (V_attachState(vp) != VOL_STATE_UNATTACHED));
+	       (V_attachState(vp) != VOL_STATE_UNATTACHED) &&
+	       (V_attachState(vp) != VOL_STATE_DELETED));
 
 	/* valid states:
 	 *
@@ -7192,6 +7201,7 @@ VSoftDetachVolume_r(Volume * vp, afs_uint32 thresh)
     case VOL_STATE_GOING_OFFLINE:
     case VOL_STATE_SHUTTING_DOWN:
     case VOL_STATE_SALVAGING:
+    case VOL_STATE_DELETED:
 	volume_LRU.q[vp->vlru.idx].len--;
 
 	/* create and cancel a reservation to

src/vol/volume.h

@@ -177,9 +177,10 @@ typedef enum {
     VOL_STATE_VNODE_CLOSE       = 17,   /**< volume is busy closing vnodes */
     VOL_STATE_VNODE_RELEASE     = 18,   /**< volume is busy releasing vnodes */
     VOL_STATE_VLRU_ADD          = 19,   /**< volume is busy being added to a VLRU queue */
+    VOL_STATE_DELETED           = 20,   /**< volume has been deleted by the volserver */
     /* please add new states directly above this line */
-    VOL_STATE_FREED             = 20,   /**< debugging aid */
+    VOL_STATE_FREED             = 21,   /**< debugging aid */
-    VOL_STATE_COUNT             = 21,   /**< total number of valid states */
+    VOL_STATE_COUNT             = 22,   /**< total number of valid states */
 } VolState;
 
 /**

src/vol/volume_inline.h

@@ -315,6 +315,7 @@ VIsOfflineState(VolState state)
     case VOL_STATE_UNATTACHED:
     case VOL_STATE_ERROR:
     case VOL_STATE_SALVAGING:
+    case VOL_STATE_DELETED:
 	return 1;
     default:
 	return 0;