[PATCH v2 1/3] erofs-utils: lib: export parts of erofs_pread()

[Xiang Gao]

Hi Yue,

The patch itself generally looks good to me:

On 2023/1/10 16:49, Yue Hu wrote:
> From: Yue Hu <huyue2 at coolpad.com>
> 
> Export parts of erofs_pread() to avoid duplicated code in
> erofs_verify_inode_data(). Let's make two helpers for this.
> 
> Signed-off-by: Yue Hu <huyue2 at coolpad.com>
> ---
> v2: use parameter trimmed instead of partial
> 
>   include/erofs/internal.h |   5 ++
>   lib/data.c               | 154 ++++++++++++++++++++++-----------------
>   2 files changed, 92 insertions(+), 67 deletions(-)
> 
> diff --git a/include/erofs/internal.h b/include/erofs/internal.h
> index 206913c..47240f5 100644
> --- a/include/erofs/internal.h
> +++ b/include/erofs/internal.h
> @@ -355,6 +355,11 @@ int erofs_pread(struct erofs_inode *inode, char *buf,
>   int erofs_map_blocks(struct erofs_inode *inode,
>   		struct erofs_map_blocks *map, int flags);
>   int erofs_map_dev(struct erofs_sb_info *sbi, struct erofs_map_dev *map);
> +int erofs_read_raw_data_mapped(struct erofs_map_blocks *map, char *buffer,
> +			       u64 offset, size_t len);
> +int z_erofs_read_data_mapped(struct erofs_inode *inode,
> +			struct erofs_map_blocks *map, char *raw, char *buffer,
> +			erofs_off_t skip, erofs_off_t length, bool trimmed);
>   
>   static inline int erofs_get_occupied_size(const struct erofs_inode *inode,
>   					  erofs_off_t *size)
> diff --git a/lib/data.c b/lib/data.c
> index 76a6677..d8c6076 100644
> --- a/lib/data.c
> +++ b/lib/data.c
> @@ -158,19 +158,38 @@ int erofs_map_dev(struct erofs_sb_info *sbi, struct erofs_map_dev *map)
>   	return 0;
>   }
>   
> +int erofs_read_raw_data_mapped(struct erofs_map_blocks *map, char *buffer,

erofs_read_one_data?

> +				u64 offset, size_t len)
> +{
> +	struct erofs_map_dev mdev;
> +	int ret;
> +
> +	mdev = (struct erofs_map_dev) {
> +		.m_deviceid = map->m_deviceid,
> +		.m_pa = map->m_pa,
> +	};
> +	ret = erofs_map_dev(&sbi, &mdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = dev_read(mdev.m_deviceid, buffer, mdev.m_pa + offset, len);
> +	if (ret < 0)
> +		return -EIO;
> +	return 0;
> +}
> +
>   static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
>   			       erofs_off_t size, erofs_off_t offset)
>   {
>   	struct erofs_map_blocks map = {
>   		.index = UINT_MAX,
>   	};
> -	struct erofs_map_dev mdev;
>   	int ret;
>   	erofs_off_t ptr = offset;
>   
>   	while (ptr < offset + size) {
>   		char *const estart = buffer + ptr - offset;
> -		erofs_off_t eend;
> +		erofs_off_t eend, moff = 0;
>   
>   		map.m_la = ptr;
>   		ret = erofs_map_blocks(inode, &map, 0);
> @@ -179,14 +198,6 @@ static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
>   
>   		DBG_BUGON(map.m_plen != map.m_llen);
>   
> -		mdev = (struct erofs_map_dev) {
> -			.m_deviceid = map.m_deviceid,
> -			.m_pa = map.m_pa,
> -		};
> -		ret = erofs_map_dev(&sbi, &mdev);
> -		if (ret)
> -			return ret;
> -
>   		/* trim extent */
>   		eend = min(offset + size, map.m_la + map.m_llen);
>   		DBG_BUGON(ptr < map.m_la);
> @@ -204,19 +215,74 @@ static int erofs_read_raw_data(struct erofs_inode *inode, char *buffer,
>   		}
>   
>   		if (ptr > map.m_la) {
> -			mdev.m_pa += ptr - map.m_la;
> +			moff = ptr - map.m_la;
>   			map.m_la = ptr;
>   		}
>   
> -		ret = dev_read(mdev.m_deviceid, estart, mdev.m_pa,
> -			       eend - map.m_la);
> -		if (ret < 0)
> -			return -EIO;
> +		ret = erofs_read_raw_data_mapped(&map, estart, moff,
> +						 eend - map.m_la);
> +		if (ret)
> +			return ret;
>   		ptr = eend;
>   	}
>   	return 0;
>   }
>   
> +int z_erofs_read_data_mapped(struct erofs_inode *inode,

z_erofs_read_one_data?

Thanks,
Gao Xiang