1 files changed, 54 insertions, 12 deletions

diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c
index 17f72a7..48f7550 100644
--- a/sys/kern/vfs_cache.c
+++ b/sys/kern/vfs_cache.c
@@ -330,23 +330,27 @@ sysctl_debug_hashstat_rawnchash(SYSCTL_HANDLER_ARGS)
 	int n_nchash;
 	int count;
 
+retry:
 	n_nchash = nchash + 1;	/* nchash is max index, not count */
 	if (!req->oldptr)
 		return SYSCTL_OUT(req, 0, n_nchash * sizeof(int));
-
-	/* Scan hash tables for applicable entries */
-	for (ncpp = nchashtbl; n_nchash > 0; n_nchash--, ncpp++) {
-		CACHE_RLOCK();
-		count = 0;
-		LIST_FOREACH(ncp, ncpp, nc_hash) {
-			count++;
-		}
+	cntbuf = malloc(n_nchash * sizeof(int), M_TEMP, M_ZERO | M_WAITOK);
+	CACHE_RLOCK();
+	if (n_nchash != nchash + 1) {
 		CACHE_RUNLOCK();
-		error = SYSCTL_OUT(req, &count, sizeof(count));
-		if (error)
-			return (error);
+		free(cntbuf, M_TEMP);
+		goto retry;
 	}
-	return (0);
+	/* Scan hash tables counting entries */
+	for (ncpp = nchashtbl, i = 0; i < n_nchash; ncpp++, i++)
+		LIST_FOREACH(ncp, ncpp, nc_hash)
+			cntbuf[i]++;
+	CACHE_RUNLOCK();
+	for (error = 0, i = 0; i < n_nchash; i++)
+		if ((error = SYSCTL_OUT(req, &cntbuf[i], sizeof(int))) != 0)
+			break;
+	free(cntbuf, M_TEMP);
+	return (error);
 }
 SYSCTL_PROC(_debug_hashstat, OID_AUTO, rawnchash, CTLTYPE_INT|CTLFLAG_RD|
     CTLFLAG_MPSAFE, 0, 0, sysctl_debug_hashstat_rawnchash, "S,int",
@@ -935,6 +939,44 @@ nchinit(void *dummy __unused)
 }
 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_SECOND, nchinit, NULL);
 
+void
+cache_changesize(int newmaxvnodes)
+{
+	struct nchashhead *new_nchashtbl, *old_nchashtbl;
+	u_long new_nchash, old_nchash;
+	struct namecache *ncp;
+	uint32_t hash;
+	int i;
+
+	new_nchashtbl = hashinit(newmaxvnodes * 2, M_VFSCACHE, &new_nchash);
+	/* If same hash table size, nothing to do */
+	if (nchash == new_nchash) {
+		free(new_nchashtbl, M_VFSCACHE);
+		return;
+	}
+	/*
+	 * Move everything from the old hash table to the new table.
+	 * None of the namecache entries in the table can be removed
+	 * because to do so, they have to be removed from the hash table.
+	 */
+	CACHE_WLOCK();
+	old_nchashtbl = nchashtbl;
+	old_nchash = nchash;
+	nchashtbl = new_nchashtbl;
+	nchash = new_nchash;
+	for (i = 0; i <= old_nchash; i++) {
+		while ((ncp = LIST_FIRST(&old_nchashtbl[i])) != NULL) {
+			hash = fnv_32_buf(nc_get_name(ncp), ncp->nc_nlen,
+			    FNV1_32_INIT);
+			hash = fnv_32_buf(&ncp->nc_dvp, sizeof(ncp->nc_dvp),
+			    hash);
+			LIST_REMOVE(ncp, nc_hash);
+			LIST_INSERT_HEAD(NCHHASH(hash), ncp, nc_hash);
+		}
+	}
+	CACHE_WUNLOCK();
+	free(old_nchashtbl, M_VFSCACHE);
+}
 
 /*
  * Invalidate all entries to a particular vnode.