erofs: fix setting up pcluster for temporary pages

pcluster should be only set up for all managed pages instead of
temporary pages. Since it currently uses page->mapping to identify,
the impact is minor for now.

[ Update: Vladimir reported the kernel log becomes polluted
  because PAGE_FLAGS_CHECK_AT_FREE flag(s) set if the page
  allocation debug option is enabled. ]

Link: https://lore.kernel.org/r/20201022145724.27284-1-hsiangkao@aol.com
Fixes: 5ddcee1f3a1c ("erofs: get rid of __stagingpage_alloc helper")
Cc: <stable@vger.kernel.org> # 5.5+
Tested-by: Vladimir Zapolskiy <vladimir@tuxera.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 50912a5420b486dd7822da1f623915beb9141aea..86fd3bf62af615dd1ba162ea7435a0a2e269d023 100644 (file)
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1078,8 +1078,11 @@ out_allocpage:
                cond_resched();
                goto repeat;
        }
-       set_page_private(page, (unsigned long)pcl);
-       SetPagePrivate(page);
+
+       if (tocache) {
+               set_page_private(page, (unsigned long)pcl);
+               SetPagePrivate(page);
+       }
 out:   /* the only exit (for tracing and debugging) */
        return page;
 }