writeback: also update wbc->nr_to_write on writeback failure

When exiting write_cache_pages early due to a non-integrity write failure,
wbc->nr_to_write currently doesn't account for the folio we just failed to
write.  This doesn't matter because the callers always ingore the value on
a failure, but moving the update to common code will allow to simplify the
code, so do it.

Link: https://lkml.kernel.org/r/20240215063649.2164017-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 2679176da316b39ed2d1335c30c4ea60c549291d..abbee369405a83f85a0e0c9cef845a3195779529 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2473,6 +2473,7 @@ continue_unlock:
                        trace_wbc_writepage(wbc, inode_to_bdi(mapping->host));
                        error = writepage(folio, wbc, data);
                        nr = folio_nr_pages(folio);
+                       wbc->nr_to_write -= nr;
                        if (unlikely(error)) {
                                /*
                                 * Handle errors according to the type of
@@ -2506,7 +2507,6 @@ continue_unlock:
                         * we tagged for writeback prior to entering this loop.
                         */
                        done_index = folio->index + nr;
-                       wbc->nr_to_write -= nr;
                        if (wbc->nr_to_write <= 0 &&
                            wbc->sync_mode == WB_SYNC_NONE) {
                                done = 1;