[PATCH 20/29] ext4: cleanup the dax handling in ext4_fill_super

[Darrick J. Wong]

On Tue, Nov 09, 2021 at 09:33:00AM +0100, Christoph Hellwig wrote:
> Only call fs_dax_get_by_bdev once the sbi has been allocated and remove
> the need for the dax_dev local variable.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> ---
>  fs/ext4/super.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index eb4df43abd76e..b60401bb1c310 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -3879,7 +3879,6 @@ static void ext4_setup_csum_trigger(struct super_block *sb,
>  
>  static int ext4_fill_super(struct super_block *sb, void *data, int silent)
>  {
> -	struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
>  	char *orig_data = kstrdup(data, GFP_KERNEL);
>  	struct buffer_head *bh, **group_desc;
>  	struct ext4_super_block *es = NULL;
> @@ -3910,12 +3909,12 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
>  	if ((data && !orig_data) || !sbi)
>  		goto out_free_base;
>  
> -	sbi->s_daxdev = dax_dev;
>  	sbi->s_blockgroup_lock =
>  		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
>  	if (!sbi->s_blockgroup_lock)
>  		goto out_free_base;
>  
> +	sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev);
>  	sb->s_fs_info = sbi;
>  	sbi->s_sb = sb;
>  	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
> @@ -4300,7 +4299,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
>  		goto failed_mount;
>  	}
>  
> -	if (dax_dev) {
> +	if (sbi->s_daxdev) {
>  		if (blocksize == PAGE_SIZE)
>  			set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
>  		else
> @@ -5096,10 +5095,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
>  out_fail:
>  	sb->s_fs_info = NULL;
>  	kfree(sbi->s_blockgroup_lock);
> +	fs_put_dax(sbi->s_daxdev );

Nit: no space before the paren  ^ here.

With that fixed,
Reviewed-by: Darrick J. Wong <djwong at kernel.org>

--D

>  out_free_base:
>  	kfree(sbi);
>  	kfree(orig_data);
> -	fs_put_dax(dax_dev);
>  	return err ? err : ret;
>  }
>  
> -- 
> 2.30.2
>