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

Darrick J. Wong
2021-11-23T22:54:36Z

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@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@kernel.org>

--D

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