DAFS: Do not serialize state for invalid hosts

[openafs.git] / src / viced / host.c

diff --git a/src/viced/host.c b/src/viced/host.c
index 7f94344..59ed73e 100644 (file)
--- a/src/viced/host.c
+++ b/src/viced/host.c
@@ -2920,6 +2920,37 @@ static int h_stateVerifyUuidHash(struct fs_dump_state * state, struct host * h);
 static void h_hostToDiskEntry_r(struct host * in, struct hostDiskEntry * out);
 static void h_diskEntryToHost_r(struct hostDiskEntry * in, struct host * out);
 
+/**
+ * Is this host busy?
+ *
+ * This is just a hint and should not be trusted; this should probably only be
+ * used by the host state serialization code when trying to detect if a host
+ * can be sanely serialized to disk or not. If this function returns 1, the
+ * host may be in an invalid state and thus should not be saved to disk.
+ */
+static int
+h_isBusy_r(struct host *host)
+{
+    struct Lock *hostLock = &host->lock;
+    int locked = 0;
+
+    LOCK_LOCK(hostLock);
+    if (hostLock->excl_locked || hostLock->readers_reading) {
+       locked = 1;
+    }
+    LOCK_UNLOCK(hostLock);
+
+    if (locked) {
+       return 1;
+    }
+
+    if ((host->hostFlags & HWHO_INPROGRESS) || !(host->hostFlags & ALTADDR)) {
+       /* We shouldn't hit this if the host wasn't locked, but just in case... */
+       return 1;
+    }
+
+    return 0;
+}
 
 /* this procedure saves all host state to disk for fast startup */
 int
@@ -3241,6 +3272,16 @@ h_stateSaveHost(struct host * host, void* rock)
     struct iovec iov[4];
     int iovcnt = 2;
 
+    if (h_isBusy_r(host)) {
+       char hoststr[16];
+       ViceLog(1, ("Not saving host %s:%d to disk; host appears busy\n",
+                   afs_inet_ntoa_r(host->host, hoststr), (int)ntohs(host->port)));
+       /* Make sure we don't try to save callbacks to disk for this host, or
+        * we'll get confused on restore */
+       DeleteAllCallBacks_r(host, 1);
+       return 0;
+    }
+
     memset(&hdr, 0, sizeof(hdr));
 
     if (state->h_hdr->index_max < host->index) {
@@ -3367,6 +3408,16 @@ h_stateRestoreHost(struct fs_dump_state * state)
        osi_Assert(hcps != NULL);
     }
 
+    if ((hdsk.hostFlags & HWHO_INPROGRESS) || !(hdsk.hostFlags & ALTADDR)) {
+       char hoststr[16];
+       ViceLog(0, ("h_stateRestoreHost: skipping host %s:%d due to invalid flags 0x%x\n",
+                   afs_inet_ntoa_r(hdsk.host, hoststr), (int)ntohs(hdsk.port),
+                   (unsigned)hdsk.hostFlags));
+       bail = 0;
+       state->h_map.entries[hdsk.index].valid = FS_STATE_IDX_SKIPPED;
+       goto done;
+    }
+
     /* for restoring state, we better be able to get a host! */
     host = GetHT();
     osi_Assert(host != NULL);