[PATCH 13/14] staging/lustre/llite: do not clear uptodate bit in page delete

From: Oleg Drokin
Date: Wed Nov 02 2016 - 21:26:37 EST


From: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>

Otherwise, if the race between page fault and truncate occurs, it
will cause the page fault routine to return an EIO error.

In filemap_fault() {
page_not_uptodate:
...
ClearPageError(page);
error = mapping->a_ops->readpage(file, page);
if (!error) {
wait_on_page_locked(page);
if (!PageUptodate(page))
error = -EIO;
}
...
}

However, I tend to think this is a defect in kernel implementation,
because it assumes PageUptodate shouldn't be cleared but file read
routine doesn't make the same assumption.

Signed-off-by: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>
Reviewed-on: http://review.whamcloud.com/22827
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8633
Reviewed-by: Li Dongyang <dongyang.li@xxxxxxxxxx>
Reviewed-by: Bobi Jam <bobijam@xxxxxxxxxxx>
Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx>
---
drivers/staging/lustre/lustre/llite/vvp_page.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/staging/lustre/lustre/llite/vvp_page.c b/drivers/staging/lustre/lustre/llite/vvp_page.c
index 25490a5..23d6630 100644
--- a/drivers/staging/lustre/lustre/llite/vvp_page.c
+++ b/drivers/staging/lustre/lustre/llite/vvp_page.c
@@ -166,7 +166,6 @@ static void vvp_page_delete(const struct lu_env *env,
refc = atomic_dec_return(&page->cp_ref);
LASSERTF(refc >= 1, "page = %p, refc = %d\n", page, refc);

- ClearPageUptodate(vmpage);
ClearPagePrivate(vmpage);
vmpage->private = 0;
/*
--
2.7.4