[PATCH 4.19 135/152] staging: erofs: complete error handing of z_erofs_do_read_page

From: Greg Kroah-Hartman
Date: Mon Feb 25 2019 - 16:26:51 EST


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

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

From: Gao Xiang <gaoxiang25@xxxxxxxxxx>

commit 1e05ff36e6921ca61bdbf779f81a602863569ee3 upstream.

This patch completes error handing code of z_erofs_do_read_page.
PG_error will be set when some read error happens, therefore
z_erofs_onlinepage_endio will unlock this page without setting
PG_uptodate.

Reviewed-by: Chao Yu <yucxhao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/staging/erofs/unzip_vle.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -606,7 +606,7 @@ static int z_erofs_do_read_page(struct z

enum z_erofs_page_type page_type;
unsigned cur, end, spiltted, index;
- int err;
+ int err = 0;

/* register locked file pages as online pages in pack */
z_erofs_onlinepage_init(page);
@@ -633,12 +633,11 @@ repeat:
if (unlikely(err))
goto err_out;

- /* deal with hole (FIXME! broken now) */
if (unlikely(!(map->m_flags & EROFS_MAP_MAPPED)))
goto hitted;

DBG_BUGON(map->m_plen != 1 << sbi->clusterbits);
- BUG_ON(erofs_blkoff(map->m_pa));
+ DBG_BUGON(erofs_blkoff(map->m_pa));

err = z_erofs_vle_work_iter_begin(builder, sb, map, &fe->owned_head);
if (unlikely(err))
@@ -683,7 +682,7 @@ retry:

err = z_erofs_vle_work_add_page(builder,
newpage, Z_EROFS_PAGE_TYPE_EXCLUSIVE);
- if (!err)
+ if (likely(!err))
goto retry;
}

@@ -694,9 +693,10 @@ retry:

/* FIXME! avoid the last relundant fixup & endio */
z_erofs_onlinepage_fixup(page, index, true);
- ++spiltted;

- /* also update nr_pages and increase queued_pages */
+ /* bump up the number of spiltted parts of a page */
+ ++spiltted;
+ /* also update nr_pages */
work->nr_pages = max_t(pgoff_t, work->nr_pages, index + 1);
next_part:
/* can be used for verification */
@@ -706,16 +706,18 @@ next_part:
if (end > 0)
goto repeat;

+out:
/* FIXME! avoid the last relundant fixup & endio */
z_erofs_onlinepage_endio(page);

debugln("%s, finish page: %pK spiltted: %u map->m_llen %llu",
__func__, page, spiltted, map->m_llen);
- return 0;
+ return err;

+ /* if some error occurred while processing this page */
err_out:
- /* TODO: the missing error handing cases */
- return err;
+ SetPageError(page);
+ goto out;
}

static void z_erofs_vle_unzip_kickoff(void *ptr, int bios)