[PATCH-next v2] erofs: add support for FS_IOC_GETFSSYSFSPATH

[Gao Xiang]

On 2024/7/16 19:29, Huang Xiaojia wrote:
> FS_IOC_GETFSSYSFSPATH ioctl exposes /sys/fs path of a given filesystem,
> potentially standarizing sysfs reporting. This patch add support for
> FS_IOC_GETFSSYSFSPATH for erofs, "erofs/<dev>" will be outpt for bdev
                                                  ^ will be outputted

> case, and "erofs/[domain_id,]<fs_id>" will be output for non-bdev case.

   ^ cases,

             ^ "erofs/[domainid,]<fsid>" will be outputed for fscache cases.

> 
> Signed-off-by: Huang Xiaojia <huangxiaojia2 at huawei.com>
> ---
> v2: handle non-bdev case.
> v1: https://lore.kernel.org/all/20240624063801.2476116-1-huangxiaojia2@huawei.com/
> ---
>   fs/erofs/super.c | 15 +++++++++++++++
>   1 file changed, 15 insertions(+)
> 
> diff --git a/fs/erofs/super.c b/fs/erofs/super.c
> index 1b91d9513013..a24b6907363c 100644
> --- a/fs/erofs/super.c
> +++ b/fs/erofs/super.c
> @@ -576,6 +576,20 @@ static const struct export_operations erofs_export_ops = {
>   	.get_parent = erofs_get_parent,
>   };
>   
> +static void erofs_set_sysfs_name(struct super_block *sb)
> +{
> +	struct erofs_sb_info *sbi = EROFS_SB(sb);
> +
> +	if (erofs_is_fscache_mode(sb)) {
> +		if (sbi->domain_id)
> +			super_set_sysfs_name_generic(sb, "%s,%s", sbi->domain_id, sbi->fsid);

Overly long line.

> +		else
> +			super_set_sysfs_name_generic(sb, "%s", sbi->fsid);

How about just get rid of the else arm, like:

		...
		return;
	}
	super_set_sysfs_name_id(sb);
}

Otherwise it looks good to me, but I may need to find time to
test myself.

Thanks,
Gao Xiang


> +	} else {
> +		super_set_sysfs_name_id(sb);
> +	}
> +}
> +
>   static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc)
>   {
>   	struct inode *inode;
> @@ -643,6 +657,7 @@ static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc)
>   		sb->s_flags |= SB_POSIXACL;
>   	else
>   		sb->s_flags &= ~SB_POSIXACL;
> +	erofs_set_sysfs_name(sb);
>   
>   #ifdef CONFIG_EROFS_FS_ZIP
>   	xa_init(&sbi->managed_pslots);