Re: [PATCH -next v2 7/7] ext4: remove EXT4_GET_BLOCKS_IO_CREATE_EXT

[Baokun Li <libaokun1@huawei.com>]

On 2025-12-23 09:18, Zhang Yi wrote:
> From: Zhang Yi <yi.zhang@huawei.com>
>
> We do not use EXT4_GET_BLOCKS_IO_CREATE_EXT or split extents before
> submitting I/O; therefore, remove the related code.
>
> Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
> Reviewed-by: Jan Kara <jack@suse.cz>

Looks good. Feel free to add:

Reviewed-by: Baokun Li <libaokun1@huawei.com>

> ---
>  fs/ext4/ext4.h    |  9 ---------
>  fs/ext4/extents.c | 29 -----------------------------
>  fs/ext4/inode.c   | 11 -----------
>  3 files changed, 49 deletions(-)
>
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 9a71357f192d..174c51402864 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -707,15 +707,6 @@ enum {
>  	 * found an unwritten extent, we need to split it.
>  	 */
>  #define EXT4_GET_BLOCKS_SPLIT_NOMERGE		0x0008
> -	/*
> -	 * Caller is from the dio or dioread_nolock buffered IO, reqest to
> -	 * create an unwritten extent if it does not exist or split the
> -	 * found unwritten extent. Also do not merge the newly created
> -	 * unwritten extent, io end will convert unwritten to written,
> -	 * and try to merge the written extent.
> -	 */
> -#define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_SPLIT_NOMERGE|\
> -					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
>  	/* Convert unwritten extent to initialized. */
>  #define EXT4_GET_BLOCKS_CONVERT			0x0010
>  	/* Eventual metadata allocation (due to growing extent tree)
> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
> index c98f7c5482b4..c7c66ab825e7 100644
> --- a/fs/ext4/extents.c
> +++ b/fs/ext4/extents.c
> @@ -3925,34 +3925,6 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode,
>  	trace_ext4_ext_handle_unwritten_extents(inode, map, flags,
>  						*allocated, newblock);
>  
> -	/* get_block() before submitting IO, split the extent */
> -	if (flags & EXT4_GET_BLOCKS_SPLIT_NOMERGE) {
> -		int depth;
> -
> -		path = ext4_split_convert_extents(handle, inode, map, path,
> -						  flags, allocated);
> -		if (IS_ERR(path))
> -			return path;
> -		/*
> -		 * shouldn't get a 0 allocated when splitting an extent unless
> -		 * m_len is 0 (bug) or extent has been corrupted
> -		 */
> -		if (unlikely(*allocated == 0)) {
> -			EXT4_ERROR_INODE(inode,
> -					 "unexpected allocated == 0, m_len = %u",
> -					 map->m_len);
> -			err = -EFSCORRUPTED;
> -			goto errout;
> -		}
> -		/* Don't mark unwritten if the extent has been zeroed out. */
> -		path = ext4_find_extent(inode, map->m_lblk, path, flags);
> -		if (IS_ERR(path))
> -			return path;
> -		depth = ext_depth(inode);
> -		if (ext4_ext_is_unwritten(path[depth].p_ext))
> -			map->m_flags |= EXT4_MAP_UNWRITTEN;
> -		goto out;
> -	}
>  	/* IO end_io complete, convert the filled extent to written */
>  	if (flags & EXT4_GET_BLOCKS_CONVERT) {
>  		path = ext4_convert_unwritten_extents_endio(handle, inode,
> @@ -4006,7 +3978,6 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode,
>  		goto errout;
>  	}
>  
> -out:
>  	map->m_flags |= EXT4_MAP_NEW;
>  map_out:
>  	map->m_flags |= EXT4_MAP_MAPPED;
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 67fe7d0f47e3..2e79b09fe2f0 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -588,7 +588,6 @@ static int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
>  static int ext4_map_create_blocks(handle_t *handle, struct inode *inode,
>  				  struct ext4_map_blocks *map, int flags)
>  {
> -	struct extent_status es;
>  	unsigned int status;
>  	int err, retval = 0;
>  
> @@ -649,16 +648,6 @@ static int ext4_map_create_blocks(handle_t *handle, struct inode *inode,
>  			return err;
>  	}
>  
> -	/*
> -	 * If the extent has been zeroed out, we don't need to update
> -	 * extent status tree.
> -	 */
> -	if (flags & EXT4_GET_BLOCKS_SPLIT_NOMERGE &&
> -	    ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es, &map->m_seq)) {
> -		if (ext4_es_is_written(&es))
> -			return retval;
> -	}
> -
>  	status = map->m_flags & EXT4_MAP_UNWRITTEN ?
>  			EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
>  	ext4_es_insert_extent(inode, map->m_lblk, map->m_len, map->m_pblk,