[PATCH] fix swap cluster offset

When we've allocated SWAPFILE_CLUSTER pages, ->cluster_next should be the
first index of swap cluster.  But current code probably sets it wrong offset.

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 1f9cf0d073b84caad71234ddfb091618906d3047..365ed6ff182d218b5d762d1a3541910a594780ff 100644 (file)
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -116,7 +116,7 @@ static inline unsigned long scan_swap_map(struct swap_info_struct *si)
                                last_in_cluster = offset + SWAPFILE_CLUSTER;
                        else if (offset == last_in_cluster) {
                                spin_lock(&swap_lock);
-                               si->cluster_next = offset-SWAPFILE_CLUSTER-1;
+                               si->cluster_next = offset-SWAPFILE_CLUSTER+1;
                                goto cluster;
                        }
                        if (unlikely(--latency_ration < 0)) {