+ err = btrfs_parse_options(tree_root, options);
+ if (err)
+ goto fail_sb_buffer;
+
+ /*
+ * we need to start all the end_io workers up front because the
+ * queue work function gets called at interrupt time, and so it
+ * cannot dynamically grow.
+ */
+ btrfs_init_workers(&fs_info->workers, "worker",
+ fs_info->thread_pool_size);
+
+ btrfs_init_workers(&fs_info->submit_workers, "submit",
+ min_t(u64, fs_devices->num_devices,
+ fs_info->thread_pool_size));
+
+ /* a higher idle thresh on the submit workers makes it much more
+ * likely that bios will be send down in a sane order to the
+ * devices
+ */
+ fs_info->submit_workers.idle_thresh = 64;
+
+ /* fs_info->workers is responsible for checksumming file data
+ * blocks and metadata. Using a larger idle thresh allows each
+ * worker thread to operate on things in roughly the order they
+ * were sent by the writeback daemons, improving overall locality
+ * of the IO going down the pipe.
+ */
+ fs_info->workers.idle_thresh = 128;
+
+ btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1);
+ btrfs_init_workers(&fs_info->endio_workers, "endio",
+ fs_info->thread_pool_size);
+ btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
+ fs_info->thread_pool_size);
+
+ /*
+ * endios are largely parallel and should have a very
+ * low idle thresh
+ */
+ fs_info->endio_workers.idle_thresh = 4;
+ fs_info->endio_write_workers.idle_thresh = 64;
+
+ btrfs_start_workers(&fs_info->workers, 1);
+ btrfs_start_workers(&fs_info->submit_workers, 1);
+ btrfs_start_workers(&fs_info->fixup_workers, 1);
+ btrfs_start_workers(&fs_info->endio_workers, fs_info->thread_pool_size);
+ btrfs_start_workers(&fs_info->endio_write_workers,
+ fs_info->thread_pool_size);
+
+ err = -EINVAL;
+ if (btrfs_super_num_devices(disk_super) > fs_devices->open_devices) {