Re: [PATCH v4 6/7] hfsplus: introduce iomap-based file_operations

[Christoph Hellwig <hch@lst.de>]

On Mon, Sep 14, 2026 at 04:39:40PM -0700, Viacheslav Dubeyko wrote:
> This patch

Patch descriptions are not supposed to start with "this patch".
By the time this fets into git, it isn't a patch any more :)

> @@ -55,7 +58,6 @@ int hfsplus_file_fsync(struct file *file, loff_t start, loff_t end,
>  	error = file_write_and_wait_range(file, start, end);
>  	if (error)
>  		return error;
> -	inode_lock(inode);
>  
>  	/*
>  	 * Sync inode metadata into the catalog and extent trees.
> @@ -114,15 +116,184 @@ int hfsplus_file_fsync(struct file *file, loff_t start, loff_t end,
>  	if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
>  		blkdev_issue_flush(inode->i_sb->s_bdev);
>  
> +	return error;
> +}

Changing fsync locking feels like something that should move
into a well-documented prep patch.

> +/*
> + * hfsplus_fallback_buffered_write() - fall back to buffered I/O for the

Pointless function name in the comment.

> + * tail of a write that iomap_dio_rw() could not perform directly
> + * (unaligned tail, or no blocks could be mapped without allocation
> + * outside the direct path).
> + */
> +static ssize_t hfsplus_fallback_buffered_write(struct kiocb *iocb,
> +						struct iov_iter *from)
> +{

Can this use direct_write_fallback()?

> +	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
> +	loff_t total_capacity;
> +	ssize_t ret;
> +	int err;
> +
> +	inode_lock(inode);
> +
> +	ret = generic_write_checks(iocb, iter);
> +	if (ret <= 0)
> +		goto unlock;
> +
> +	total_capacity = (loff_t)sbi->total_blocks << sbi->alloc_blksz_shift;
> +	if (iocb->ki_pos >= total_capacity) {

This is weird.  The total capacity should not matter for a write.