---

yaml --- r: 333212 b: refs/heads/master c: 5a65503 h: refs/heads/master v: v3
git-mirror · Oct 2, 2012 · efe5fdb · efe5fdb
1 parent 50ff7d6
commit efe5fdb
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 038d6493763d900797dfeb555502d3b0d8103fba
+refs/heads/master: 5a65503f3dbdb4aa1cd6cb58c479c015d093292b
diff --git a/trunk/fs/nfs/pnfs.c b/trunk/fs/nfs/pnfs.c
@@ -549,6 +549,15 @@ pnfs_destroy_all_layouts(struct nfs_client *clp)
 	}
 }
 
+/*
+ * Compare 2 layout stateid sequence ids, to see which is newer,
+ * taking into account wraparound issues.
+ */
+static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
+{
+	return (s32)s1 - (s32)s2 > 0;
+}
+
 /* update lo->plh_stateid with new if is more recent */
 void
 pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
@@ -558,7 +567,7 @@ pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 
 	oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 	newseq = be32_to_cpu(new->seqid);
-	if (list_empty(&lo->plh_segs) || (int)(newseq - oldseq) > 0) {
+	if (list_empty(&lo->plh_segs) || pnfs_seqid_is_newer(newseq, oldseq)) {
 		nfs4_stateid_copy(&lo->plh_stateid, new);
 		if (update_barrier) {
 			u32 new_barrier = be32_to_cpu(new->seqid);