[PATCH 3/4] f2fs: compress: fix error path in prepare_compress_overwrite()

[Chao Yu <yuchao0@huawei.com>]

- fix to release cluster pages in retry flow
- fix to call f2fs_put_dnode() & __do_map_lock() in error path

Signed-off-by: Chao Yu <yuchao0@huawei.com>
---
 fs/f2fs/compress.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index fc4510729654..3390351d2e39 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -626,20 +626,26 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 	}
 
 	for (i = 0; i < cc->cluster_size; i++) {
+		f2fs_bug_on(sbi, cc->rpages[i]);
+
 		page = find_lock_page(mapping, start_idx + i);
 		f2fs_bug_on(sbi, !page);
 
 		f2fs_wait_on_page_writeback(page, DATA, true, true);
 
-		cc->rpages[i] = page;
+		f2fs_compress_ctx_add_page(cc, page);
 		f2fs_put_page(page, 0);
 
 		if (!PageUptodate(page)) {
-			for (idx = 0; idx < cc->cluster_size; idx++) {
-				f2fs_put_page(cc->rpages[idx],
-						(idx <= i) ? 1 : 0);
+			for (idx = 0; idx <= i; idx++) {
+				unlock_page(cc->rpages[idx]);
 				cc->rpages[idx] = NULL;
 			}
+			for (idx = 0; idx < cc->cluster_size; idx++) {
+				page = find_lock_page(mapping, start_idx + idx);
+				f2fs_put_page(page, 1);
+				f2fs_put_page(page, 0);
+			}
 			kvfree(cc->rpages);
 			cc->nr_rpages = 0;
 			goto retry;
@@ -654,16 +660,20 @@ static int prepare_compress_overwrite(struct compress_ctx *cc,
 		for (i = cc->cluster_size - 1; i > 0; i--) {
 			ret = f2fs_get_block(&dn, start_idx + i);
 			if (ret) {
-				/* TODO: release preallocate blocks */
 				i = cc->cluster_size;
-				goto unlock_pages;
+				break;
 			}
 
 			if (dn.data_blkaddr != NEW_ADDR)
 				break;
 		}
 
+		f2fs_put_dnode(&dn);
+
 		__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
+
+		if (ret)
+			goto unlock_pages;
 	}
 
 	*fsdata = cc->rpages;
-- 
2.18.0.rc1