Re: [PATCH 1/3] iomap: return VM_FAULT_* codes from iomap_page_mkwrite

[Ross Zwisler <ross.zwisler@linux.intel.com>]

On Thu, Aug 24, 2017 at 05:22:05PM +0200, Christoph Hellwig wrote:
> Signed-off-by: Christoph Hellwig <hch@lst.de>

This is obviously correct, but the lack of changelog makes it unclear why the
change is being made.  Does a later patch in the series depend on
iomap_page_mkwrite() returning VM_FAULT_* codes?  Is this just cleanup so you
can hide the block_page_mkwrite_return() call inside of iomap_page_mkwrite()?

I think it's the former, so the logic in __xfs_filemap_fault() is simpler?

Anyway, the code is correct, so you can add:

Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>

> ---
>  fs/iomap.c        | 4 ++--
>  fs/xfs/xfs_file.c | 1 -
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/iomap.c b/fs/iomap.c
> index 039266128b7f..22ffdfeabeda 100644
> --- a/fs/iomap.c
> +++ b/fs/iomap.c
> @@ -477,10 +477,10 @@ int iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops)
>  
>  	set_page_dirty(page);
>  	wait_for_stable_page(page);
> -	return 0;
> +	return VM_FAULT_LOCKED;
>  out_unlock:
>  	unlock_page(page);
> -	return ret;
> +	return block_page_mkwrite_return(ret);
>  }
>  EXPORT_SYMBOL_GPL(iomap_page_mkwrite);
>  
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index afa226b8c290..4213f02325a2 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -1035,7 +1035,6 @@ xfs_filemap_page_mkwrite(
>  		ret = dax_iomap_fault(vmf, PE_SIZE_PTE, NULL, &xfs_iomap_ops);
>  	} else {
>  		ret = iomap_page_mkwrite(vmf, &xfs_iomap_ops);
> -		ret = block_page_mkwrite_return(ret);
>  	}
>  
>  	xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
> -- 
> 2.11.0
>