f2fs: fix to check page dirty status before writeback

In f2fs_write_raw_pages(), we need to check page dirty status before
writeback, because there could be a racer (e.g. reclaimer) helps
writebacking the dirty page.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index cde6868c77bb7b0e66c00c6ed67213868f293604..dcc9f807a647397fa4f0372b73917476900d852f 100644 (file)
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -1322,6 +1322,12 @@ retry_write:
                                congestion_wait(BLK_RW_ASYNC,
                                                DEFAULT_IO_TIMEOUT);
                                lock_page(cc->rpages[i]);
+
+                               if (!PageDirty(cc->rpages[i])) {
+                                       unlock_page(cc->rpages[i]);
+                                       continue;
+                               }
+
                                clear_page_dirty_for_io(cc->rpages[i]);
                                goto retry_write;
                        }