Commit 449813515d3e ("block, fs: Restore the per-bio/request data lifetime fields") restored write-hint support in ext4. But that is applicable only for direct IO. This patch supports passing write-hint for buffered IO from ext4 file system to block layer by filling bi_write_hint of struct bio in io_submit_add_bh(). Signed-off-by: j.xia <j.xia@xxxxxxxxxxx> --- fs/ext4/page-io.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index ad5543866d21..bb8b17c394d4 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -417,8 +417,10 @@ static void io_submit_add_bh(struct ext4_io_submit *io, submit_and_retry: ext4_io_submit(io); } - if (io->io_bio == NULL) + if (io->io_bio == NULL) { io_submit_init_bio(io, bh); + io->io_bio->bi_write_hint = inode->i_write_hint; + } if (!bio_add_folio(io->io_bio, io_folio, bh->b_size, bh_offset(bh))) goto submit_and_retry; wbc_account_cgroup_owner(io->io_wbc, &folio->page, bh->b_size); -- 2.34.1