diff mbox series

[4/6] xfs: refactor __xfs_filemap_fault

Message ID 20240619115426.332708-5-hch@lst.de (mailing list archive)
State Superseded, archived
Headers show
Series [1/6] xfs: move the dio write relocking out of xfs_ilock_for_iomap | expand

Commit Message

Christoph Hellwig June 19, 2024, 11:53 a.m. UTC 
Split the write fault and DAX fault handling into separate helpers
so that the main fault handler is easier to follow.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_file.c | 71 ++++++++++++++++++++++++++++++-----------------
 1 file changed, 45 insertions(+), 26 deletions(-)

Comments

Darrick J. Wong June 20, 2024, 6:54 p.m. UTC | #1 
On Wed, Jun 19, 2024 at 01:53:54PM +0200, Christoph Hellwig wrote:
> Split the write fault and DAX fault handling into separate helpers
> so that the main fault handler is easier to follow.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/xfs/xfs_file.c | 71 ++++++++++++++++++++++++++++++-----------------
>  1 file changed, 45 insertions(+), 26 deletions(-)
> 
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 8aab2f66fe016f..51e50afd935895 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -1252,7 +1252,7 @@ xfs_file_llseek(
>  }
>  
>  static inline vm_fault_t
> -xfs_dax_fault(
> +xfs_dax_fault_locked(
>  	struct vm_fault		*vmf,
>  	unsigned int		order,
>  	bool			write_fault)
> @@ -1273,6 +1273,45 @@ xfs_dax_fault(
>  	return ret;
>  }
>  
> +static vm_fault_t
> +xfs_dax_fault(

Oh, hey, you /did/ split the dax handling into two helpers.

Would you mind renaming this xfs_dax_read_fault since this doesn't
handle write faults?

With that changed,
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> +	struct vm_fault		*vmf,
> +	unsigned int		order)
> +{
> +	struct xfs_inode	*ip = XFS_I(file_inode(vmf->vma->vm_file));
> +	unsigned int		lock_mode;
> +	vm_fault_t		ret;
> +
> +	lock_mode = xfs_ilock_for_write_fault(ip);
> +	ret = xfs_dax_fault_locked(vmf, order, false);
> +	xfs_iunlock(ip, lock_mode);
> +
> +	return ret;
> +}
> +
> +static vm_fault_t
> +xfs_write_fault(
> +	struct vm_fault		*vmf,
> +	unsigned int		order)
> +{
> +	struct inode		*inode = file_inode(vmf->vma->vm_file);
> +	unsigned int		lock_mode;
> +	vm_fault_t		ret;
> +
> +	sb_start_pagefault(inode->i_sb);
> +	file_update_time(vmf->vma->vm_file);
> +
> +	lock_mode = xfs_ilock_for_write_fault(XFS_I(inode));
> +	if (IS_DAX(inode))
> +		ret = xfs_dax_fault_locked(vmf, order, true);
> +	else
> +		ret = iomap_page_mkwrite(vmf, &xfs_page_mkwrite_iomap_ops);
> +	xfs_iunlock(XFS_I(inode), lock_mode);
> +
> +	sb_end_pagefault(inode->i_sb);
> +	return ret;
> +}
> +
>  /*
>   * Locking for serialisation of IO during page faults. This results in a lock
>   * ordering of:
> @@ -1290,34 +1329,14 @@ __xfs_filemap_fault(
>  	bool			write_fault)
>  {
>  	struct inode		*inode = file_inode(vmf->vma->vm_file);
> -	struct xfs_inode	*ip = XFS_I(inode);
> -	vm_fault_t		ret;
> -	unsigned int		lock_mode = 0;
>  
> -	trace_xfs_filemap_fault(ip, order, write_fault);
> -
> -	if (write_fault) {
> -		sb_start_pagefault(inode->i_sb);
> -		file_update_time(vmf->vma->vm_file);
> -	}
> -
> -	if (IS_DAX(inode) || write_fault)
> -		lock_mode = xfs_ilock_for_write_fault(XFS_I(inode));
> -
> -	if (IS_DAX(inode)) {
> -		ret = xfs_dax_fault(vmf, order, write_fault);
> -	} else if (write_fault) {
> -		ret = iomap_page_mkwrite(vmf, &xfs_page_mkwrite_iomap_ops);
> -	} else {
> -		ret = filemap_fault(vmf);
> -	}
> -
> -	if (lock_mode)
> -		xfs_iunlock(XFS_I(inode), lock_mode);
> +	trace_xfs_filemap_fault(XFS_I(inode), order, write_fault);
>  
>  	if (write_fault)
> -		sb_end_pagefault(inode->i_sb);
> -	return ret;
> +		return xfs_write_fault(vmf, order);
> +	if (IS_DAX(inode))
> +		return xfs_dax_fault(vmf, order);
> +	return filemap_fault(vmf);
>  }
>  
>  static inline bool
> -- 
> 2.43.0
> 
>
Christoph Hellwig June 21, 2024, 5:08 a.m. UTC | #2 
On Thu, Jun 20, 2024 at 11:54:06AM -0700, Darrick J. Wong wrote:
> Oh, hey, you /did/ split the dax handling into two helpers.
> 
> Would you mind renaming this xfs_dax_read_fault since this doesn't
> handle write faults?

Sure.
diff mbox series

Patch

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 8aab2f66fe016f..51e50afd935895 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1252,7 +1252,7 @@  xfs_file_llseek(
 }
 
 static inline vm_fault_t
-xfs_dax_fault(
+xfs_dax_fault_locked(
 	struct vm_fault		*vmf,
 	unsigned int		order,
 	bool			write_fault)
@@ -1273,6 +1273,45 @@  xfs_dax_fault(
 	return ret;
 }
 
+static vm_fault_t
+xfs_dax_fault(
+	struct vm_fault		*vmf,
+	unsigned int		order)
+{
+	struct xfs_inode	*ip = XFS_I(file_inode(vmf->vma->vm_file));
+	unsigned int		lock_mode;
+	vm_fault_t		ret;
+
+	lock_mode = xfs_ilock_for_write_fault(ip);
+	ret = xfs_dax_fault_locked(vmf, order, false);
+	xfs_iunlock(ip, lock_mode);
+
+	return ret;
+}
+
+static vm_fault_t
+xfs_write_fault(
+	struct vm_fault		*vmf,
+	unsigned int		order)
+{
+	struct inode		*inode = file_inode(vmf->vma->vm_file);
+	unsigned int		lock_mode;
+	vm_fault_t		ret;
+
+	sb_start_pagefault(inode->i_sb);
+	file_update_time(vmf->vma->vm_file);
+
+	lock_mode = xfs_ilock_for_write_fault(XFS_I(inode));
+	if (IS_DAX(inode))
+		ret = xfs_dax_fault_locked(vmf, order, true);
+	else
+		ret = iomap_page_mkwrite(vmf, &xfs_page_mkwrite_iomap_ops);
+	xfs_iunlock(XFS_I(inode), lock_mode);
+
+	sb_end_pagefault(inode->i_sb);
+	return ret;
+}
+
 /*
  * Locking for serialisation of IO during page faults. This results in a lock
  * ordering of:
@@ -1290,34 +1329,14 @@  __xfs_filemap_fault(
 	bool			write_fault)
 {
 	struct inode		*inode = file_inode(vmf->vma->vm_file);
-	struct xfs_inode	*ip = XFS_I(inode);
-	vm_fault_t		ret;
-	unsigned int		lock_mode = 0;
 
-	trace_xfs_filemap_fault(ip, order, write_fault);
-
-	if (write_fault) {
-		sb_start_pagefault(inode->i_sb);
-		file_update_time(vmf->vma->vm_file);
-	}
-
-	if (IS_DAX(inode) || write_fault)
-		lock_mode = xfs_ilock_for_write_fault(XFS_I(inode));
-
-	if (IS_DAX(inode)) {
-		ret = xfs_dax_fault(vmf, order, write_fault);
-	} else if (write_fault) {
-		ret = iomap_page_mkwrite(vmf, &xfs_page_mkwrite_iomap_ops);
-	} else {
-		ret = filemap_fault(vmf);
-	}
-
-	if (lock_mode)
-		xfs_iunlock(XFS_I(inode), lock_mode);
+	trace_xfs_filemap_fault(XFS_I(inode), order, write_fault);
 
 	if (write_fault)
-		sb_end_pagefault(inode->i_sb);
-	return ret;
+		return xfs_write_fault(vmf, order);
+	if (IS_DAX(inode))
+		return xfs_dax_fault(vmf, order);
+	return filemap_fault(vmf);
 }
 
 static inline bool