Date:   Tue, 23 Nov 2021 15:01:24 -0800
From:   "Darrick J. Wong" <djwong@kernel.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        Mike Snitzer <snitzer@redhat.com>,
        Ira Weiny <ira.weiny@intel.com>, dm-devel@redhat.com,
        linux-xfs@vger.kernel.org, nvdimm@lists.linux.dev,
        linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org,
        virtualization@lists.linux-foundation.org
Subject: Re: [PATCH 23/29] xfs: use IOMAP_DAX to check for DAX mappings
Message-ID: <20211123230124.GR266024@magnolia>
References: <20211109083309.584081-1-hch@lst.de>
 <20211109083309.584081-24-hch@lst.de>
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In-Reply-To: <20211109083309.584081-24-hch@lst.de>
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On Tue, Nov 09, 2021 at 09:33:03AM +0100, Christoph Hellwig wrote:
> Use the explicit DAX flag instead of checking the inode flag in the
> iomap code.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Any particular reason to pass this in as a flag vs. querying the inode?

Doesn't really bother me either way, was just curious.
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
>  fs/xfs/xfs_iomap.c | 7 ++++---
>  fs/xfs/xfs_iomap.h | 3 ++-
>  fs/xfs/xfs_pnfs.c  | 2 +-
>  3 files changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
> index 604000b6243ec..8cef3b68cba78 100644
> --- a/fs/xfs/xfs_iomap.c
> +++ b/fs/xfs/xfs_iomap.c
> @@ -188,6 +188,7 @@ xfs_iomap_write_direct(
>  	struct xfs_inode	*ip,
>  	xfs_fileoff_t		offset_fsb,
>  	xfs_fileoff_t		count_fsb,
> +	unsigned int		flags,
>  	struct xfs_bmbt_irec	*imap)
>  {
>  	struct xfs_mount	*mp = ip->i_mount;
> @@ -229,7 +230,7 @@ xfs_iomap_write_direct(
>  	 * the reserve block pool for bmbt block allocation if there is no space
>  	 * left but we need to do unwritten extent conversion.
>  	 */
> -	if (IS_DAX(VFS_I(ip))) {
> +	if (flags & IOMAP_DAX) {
>  		bmapi_flags = XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO;
>  		if (imap->br_state == XFS_EXT_UNWRITTEN) {
>  			force = true;
> @@ -620,7 +621,7 @@ imap_needs_alloc(
>  	    imap->br_startblock == DELAYSTARTBLOCK)
>  		return true;
>  	/* we convert unwritten extents before copying the data for DAX */
> -	if (IS_DAX(inode) && imap->br_state == XFS_EXT_UNWRITTEN)
> +	if ((flags & IOMAP_DAX) && imap->br_state == XFS_EXT_UNWRITTEN)
>  		return true;
>  	return false;
>  }
> @@ -826,7 +827,7 @@ xfs_direct_write_iomap_begin(
>  	xfs_iunlock(ip, lockmode);
>  
>  	error = xfs_iomap_write_direct(ip, offset_fsb, end_fsb - offset_fsb,
> -			&imap);
> +			flags, &imap);
>  	if (error)
>  		return error;
>  
> diff --git a/fs/xfs/xfs_iomap.h b/fs/xfs/xfs_iomap.h
> index f1a281ab9328c..5648262a71736 100644
> --- a/fs/xfs/xfs_iomap.h
> +++ b/fs/xfs/xfs_iomap.h
> @@ -12,7 +12,8 @@ struct xfs_inode;
>  struct xfs_bmbt_irec;
>  
>  int xfs_iomap_write_direct(struct xfs_inode *ip, xfs_fileoff_t offset_fsb,
> -		xfs_fileoff_t count_fsb, struct xfs_bmbt_irec *imap);
> +		xfs_fileoff_t count_fsb, unsigned int flags,
> +		struct xfs_bmbt_irec *imap);
>  int xfs_iomap_write_unwritten(struct xfs_inode *, xfs_off_t, xfs_off_t, bool);
>  xfs_fileoff_t xfs_iomap_eof_align_last_fsb(struct xfs_inode *ip,
>  		xfs_fileoff_t end_fsb);
> diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c
> index 5e1d29d8b2e73..e188e1cf97cc5 100644
> --- a/fs/xfs/xfs_pnfs.c
> +++ b/fs/xfs/xfs_pnfs.c
> @@ -155,7 +155,7 @@ xfs_fs_map_blocks(
>  		xfs_iunlock(ip, lock_flags);
>  
>  		error = xfs_iomap_write_direct(ip, offset_fsb,
> -				end_fsb - offset_fsb, &imap);
> +				end_fsb - offset_fsb, 0, &imap);
>  		if (error)
>  			goto out_unlock;
>  
> -- 
> 2.30.2
>