Re: [PATCH v10 04/41] btrfs: get zone information of zoned block devices

[Anand Jain <anand.jain@oracle.com>]

> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
> index 8840a4fa81eb..ed55014fd1bd 100644
> --- a/fs/btrfs/super.c
> +++ b/fs/btrfs/super.c
> @@ -2462,6 +2462,11 @@ static void __init btrfs_print_mod_info(void)
>   #endif
>   #ifdef CONFIG_BTRFS_FS_REF_VERIFY
>   			", ref-verify=on"
> +#endif
> +#ifdef CONFIG_BLK_DEV_ZONED
> +			", zoned=yes"
> +#else
> +			", zoned=no"
>   #endif

IMO, we don't need this, as most of the generic kernel will be compiled
with the CONFIG_BLK_DEV_ZONED defined.
For review purpose we may want to know if the mounted device
is a zoned device. So log of zone device and its type may be useful
when we have verified the zoned devices in the open_ctree().

> @@ -374,6 +375,7 @@ void btrfs_free_device(struct btrfs_device *device)
>   	rcu_string_free(device->name);
>   	extent_io_tree_release(&device->alloc_state);
>   	bio_put(device->flush_bio);

> +	btrfs_destroy_dev_zone_info(device);

Free of btrfs_device::zone_info is already happening in the path..

  btrfs_close_one_device()
    btrfs_destroy_dev_zone_info()

  We don't need this..

  btrfs_free_device()
   btrfs_destroy_dev_zone_info()


> @@ -2543,6 +2551,14 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>   	}
>   	rcu_assign_pointer(device->name, name);
>   
> +	device->fs_info = fs_info;
> +	device->bdev = bdev;
> +
> +	/* Get zone type information of zoned block devices */
> +	ret = btrfs_get_dev_zone_info(device);
> +	if (ret)
> +		goto error_free_device;
> +
>   	trans = btrfs_start_transaction(root, 0);
>   	if (IS_ERR(trans)) {
>   		ret = PTR_ERR(trans);

It should be something like goto error_free_zone from here.


> @@ -2707,6 +2721,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
>   		sb->s_flags |= SB_RDONLY;
>   	if (trans)
>   		btrfs_end_transaction(trans);


error_free_zone:
> +	btrfs_destroy_dev_zone_info(device);
>   error_free_device:
>   	btrfs_free_device(device);
>   error:

  As mentioned we don't need btrfs_destroy_dev_zone_info()
  again in  btrfs_free_device(). Otherwise we end up calling
  btrfs_destroy_dev_zone_info twice here.


Thanks, Anand