> +void btrfs_writeback_inodes_sb_nr(struct btrfs_root *root,
> + unsigned long nr_pages)
> +{
> + struct super_block *sb = root->fs_info->sb;
> +
> + if (writeback_in_progress(sb->s_bdi))
> + return;
> +
> + /*
> + * If we can not get s_umount, it means the fs is on remounting or
> + * umounting. At this time, we just sync all the delalloc file.
> + */
> + if (down_read_trylock(&sb->s_umount)) {
> + writeback_inodes_sb_nr(sb, nr_pages);
> + up_read(&sb->s_umount);
> + } else {
> + btrfs_start_delalloc_inodes(root, 0);
> + btrfs_wait_ordered_extents(root, 0, 0);
> + }
> +}
If that can race with umount, what prevents sb, its ->s_bdi et.al. being freed
under you?
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html