On Thu 16-04-20 07:34:53, Jeff Layton wrote:
> From: Jeff Layton <jlayton@xxxxxxxxxx>
>
> When syncing out a block device (a'la __sync_blockdev), any error
> encountered will only be recorded in the bd_inode's mapping. When the
> blockdev contains a filesystem however, we'd like to also record the
> error in the super_block that's stored there.
>
> Make mark_buffer_write_io_error also record the error in the
> corresponding super_block when a writeback error occurs and the block
> device contains a mounted superblock.
>
> Since superblocks are RCU freed, hold the rcu_read_lock to ensure
> that the superblock doesn't go away while we're marking it.
>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Looks good to me now. You can add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
> ---
> fs/buffer.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/fs/buffer.c b/fs/buffer.c
> index f73276d746bb..71be7e6cabca 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -1154,12 +1154,19 @@ EXPORT_SYMBOL(mark_buffer_dirty);
>
> void mark_buffer_write_io_error(struct buffer_head *bh)
> {
> + struct super_block *sb;
> +
> set_buffer_write_io_error(bh);
> /* FIXME: do we need to set this in both places? */
> if (bh->b_page && bh->b_page->mapping)
> mapping_set_error(bh->b_page->mapping, -EIO);
> if (bh->b_assoc_map)
> mapping_set_error(bh->b_assoc_map, -EIO);
> + rcu_read_lock();
> + sb = READ_ONCE(bh->b_bdev->bd_super);
> + if (sb)
> + errseq_set(&sb->s_wb_err, -EIO);
> + rcu_read_unlock();
> }
> EXPORT_SYMBOL(mark_buffer_write_io_error);
>
> --
> 2.25.2
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
