[PATCH 4.20 321/352] fuse: decrement NR_WRITEBACK_TEMP on the right page

From: Greg Kroah-Hartman
Date: Mon Feb 11 2019 - 09:36:32 EST


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

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

From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

commit a2ebba824106dabe79937a9f29a875f837e1b6d4 upstream.

NR_WRITEBACK_TEMP is accounted on the temporary page in the request, not
the page cache page.

Fixes: 8b284dc47291 ("fuse: writepages: handle same page rewrites")
Cc: <stable@xxxxxxxxxxxxxxx> # v3.13
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/fuse/file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1782,7 +1782,7 @@ static bool fuse_writepage_in_flight(str
spin_unlock(&fc->lock);

dec_wb_stat(&bdi->wb, WB_WRITEBACK);
- dec_node_page_state(page, NR_WRITEBACK_TEMP);
+ dec_node_page_state(new_req->pages[0], NR_WRITEBACK_TEMP);
wb_writeout_inc(&bdi->wb);
fuse_writepage_free(fc, new_req);
fuse_request_free(new_req);