2024-02-13 16:49:21

by Jan Kara

[permalink] [raw]
Subject: Re: [PATCH 2/7] ext4: refactor out ext4_generic_attr_store()

On Fri 26-01-24 16:57:11, Baokun Li wrote:
> Refactor out the function ext4_generic_attr_store() to handle the setting
> of values of various common types, with no functional changes.
>
> Signed-off-by: Baokun Li <[email protected]>
...
> -static ssize_t ext4_attr_store(struct kobject *kobj,
> - struct attribute *attr,
> - const char *buf, size_t len)
> +static ssize_t ext4_generic_attr_store(struct ext4_attr *a,
> + struct ext4_sb_info *sbi,
> + const char *buf, size_t len)
> {
> - struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
> - s_kobj);
> - struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
> - void *ptr = calc_ptr(a, sbi);
> - unsigned long t;
> int ret;
> + unsigned long t;
> + void *ptr = calc_ptr(a, sbi);
> +
> + if (!ptr)
> + return 0;
> + ret = kstrtoul(skip_spaces(buf), 0, &t);

The refactorization is nice but I'd keep the string to number conversion
inside the switch so that we can distinguish uint and ulong cases.

Honza

> + if (ret)
> + return ret;
>
> switch (a->attr_id) {
> - case attr_reserved_clusters:
> - return reserved_clusters_store(sbi, buf, len);
> case attr_pointer_ui:
> - if (!ptr)
> - return 0;
> - ret = kstrtoul(skip_spaces(buf), 0, &t);
> - if (ret)
> - return ret;
> if (t != (unsigned int)t)
> return -EINVAL;
> if (a->attr_ptr == ptr_ext4_super_block_offset)
> @@ -471,19 +467,30 @@ static ssize_t ext4_attr_store(struct kobject *kobj,
> *((unsigned int *) ptr) = t;
> return len;
> case attr_pointer_ul:
> - if (!ptr)
> - return 0;
> - ret = kstrtoul(skip_spaces(buf), 0, &t);
> - if (ret)
> - return ret;
> *((unsigned long *) ptr) = t;
> return len;
> + }
> + return 0;
> +}
> +
> +static ssize_t ext4_attr_store(struct kobject *kobj,
> + struct attribute *attr,
> + const char *buf, size_t len)
> +{
> + struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
> + s_kobj);
> + struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
> +
> + switch (a->attr_id) {
> + case attr_reserved_clusters:
> + return reserved_clusters_store(sbi, buf, len);
> case attr_inode_readahead:
> return inode_readahead_blks_store(sbi, buf, len);
> case attr_trigger_test_error:
> return trigger_test_error(sbi, buf, len);
> + default:
> + return ext4_generic_attr_store(a, sbi, buf, len);
> }
> - return 0;
> }
>
> static void ext4_sb_release(struct kobject *kobj)
> --
> 2.31.1
>
--
Jan Kara <[email protected]>
SUSE Labs, CR