[PATCH 4.19 134/152] staging: erofs: fix a bug when appling cache strategy

From: Greg Kroah-Hartman
Date: Mon Feb 25 2019 - 16:26:47 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

From: Gao Xiang <gaoxiang25@xxxxxxxxxx>

commit 0734ffbf574ee813b20899caef2fe0ed502bb783 upstream.

As described in Kconfig, the last compressed pack should be cached
for further reading for either `EROFS_FS_ZIP_CACHE_UNIPOLAR' or
`EROFS_FS_ZIP_CACHE_BIPOLAR' by design.

However, there is a bug in z_erofs_do_read_page, it will
switch `initial' to `false' at the very beginning before it decides
to cache the last compressed pack.

caching strategy should work properly after appling this patch.

Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/staging/erofs/unzip_vle.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -624,7 +624,7 @@ repeat:
/* go ahead the next map_blocks */
debugln("%s: [out-of-range] pos %llu", __func__, offset + cur);

- if (!z_erofs_vle_work_iter_end(builder))
+ if (z_erofs_vle_work_iter_end(builder))
fe->initial = false;

map->m_la = offset + cur;