Re: [PATCH v2 04/14] gfs2: replace ll_rw_block()

Andreas Gruenbacher
2022-09-05T14:10:21Z

On Thu, Sep 1, 2022 at 3:24 PM Zhang Yi <yi.zhang@huawei.com> wrote:
> ll_rw_block() is not safe for the sync read path because it cannot
> guarantee that always submitting read IO if the buffer has been locked,
> so stop using it. We also switch to new bh_readahead() helper for the
> readahead path.
>
> Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
> ---
> fs/gfs2/meta_io.c | 7 ++-----
> fs/gfs2/quota.c | 8 ++------
> 2 files changed, 4 insertions(+), 11 deletions(-)
>
> diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
> index 7e70e0ba5a6c..6ed728aae9a5 100644
> --- a/fs/gfs2/meta_io.c
> +++ b/fs/gfs2/meta_io.c
> @@ -525,8 +525,7 @@ struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
>
> if (buffer_uptodate(first_bh))
> goto out;
> - if (!buffer_locked(first_bh))
> - ll_rw_block(REQ_OP_READ | REQ_META | REQ_PRIO, 1, &first_bh);
> + bh_read_nowait(first_bh, REQ_META | REQ_PRIO);
>
> dblock++;
> extlen--;
> @@ -534,9 +533,7 @@ struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
> while (extlen) {
> bh = gfs2_getbuf(gl, dblock, CREATE);
>
> - if (!buffer_uptodate(bh) && !buffer_locked(bh))
> - ll_rw_block(REQ_OP_READ | REQ_RAHEAD | REQ_META |
> - REQ_PRIO, 1, &bh);
> + bh_readahead(bh, REQ_RAHEAD | REQ_META | REQ_PRIO);
> brelse(bh);
> dblock++;
> extlen--;
> diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
> index f201eaf59d0d..1ed17226d9ed 100644
> --- a/fs/gfs2/quota.c
> +++ b/fs/gfs2/quota.c
> @@ -745,12 +745,8 @@ static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
> }
> if (PageUptodate(page))
> set_buffer_uptodate(bh);
> - if (!buffer_uptodate(bh)) {
> - ll_rw_block(REQ_OP_READ | REQ_META | REQ_PRIO, 1, &bh);
> - wait_on_buffer(bh);
> - if (!buffer_uptodate(bh))
> - goto unlock_out;
> - }
> + if (bh_read(bh, REQ_META | REQ_PRIO) < 0)
> + goto unlock_out;
> if (gfs2_is_jdata(ip))
> gfs2_trans_add_data(ip->i_gl, bh);
> else
> --
> 2.31.1
>

Thanks for this fix; looking good.

Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>

Andreas