diff mbox series

[1/8] iomap: allow the file system to submit the writeback bios

Message ID 20241211085420.1380396-2-hch@lst.de (mailing list archive)
State New
Headers show
Series [1/8] iomap: allow the file system to submit the writeback bios | expand

Commit Message

Christoph Hellwig Dec. 11, 2024, 8:53 a.m. UTC
Change ->prepare_ioend to ->submit_ioend and require file systems that
implement it to submit the bio.  This is needed for file systems that
do their own work on the bios before submitting them to the block layer
like btrfs or zoned xfs.  To make this easier also pass the writeback
context to the method.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/iomap/buffered-io.c | 10 +++++-----
 fs/xfs/xfs_aops.c      | 13 +++++++++----
 include/linux/iomap.h  | 12 +++++++-----
 3 files changed, 21 insertions(+), 14 deletions(-)

Comments

Darrick J. Wong Dec. 12, 2024, 5:48 p.m. UTC | #1
On Wed, Dec 11, 2024 at 09:53:41AM +0100, Christoph Hellwig wrote:
> Change ->prepare_ioend to ->submit_ioend and require file systems that
> implement it to submit the bio.  This is needed for file systems that
> do their own work on the bios before submitting them to the block layer
> like btrfs or zoned xfs.  To make this easier also pass the writeback
> context to the method.

The code changes here are pretty straightforward, but please update
Documentation/filesystems/iomap/operations.rst to reflect the new name
and the new "submit the bio yourself" behavior expected of the
implementation.

--D

> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/iomap/buffered-io.c | 10 +++++-----
>  fs/xfs/xfs_aops.c      | 13 +++++++++----
>  include/linux/iomap.h  | 12 +++++++-----
>  3 files changed, 21 insertions(+), 14 deletions(-)
> 
> diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
> index 955f19e27e47..cdccf11bb3be 100644
> --- a/fs/iomap/buffered-io.c
> +++ b/fs/iomap/buffered-io.c
> @@ -1675,7 +1675,7 @@ static void iomap_writepage_end_bio(struct bio *bio)
>  }
>  
>  /*
> - * Submit the final bio for an ioend.
> + * Submit an ioend.
>   *
>   * If @error is non-zero, it means that we have a situation where some part of
>   * the submission process has failed after we've marked pages for writeback.
> @@ -1694,14 +1694,14 @@ static int iomap_submit_ioend(struct iomap_writepage_ctx *wpc, int error)
>  	 * failure happened so that the file system end I/O handler gets called
>  	 * to clean up.
>  	 */
> -	if (wpc->ops->prepare_ioend)
> -		error = wpc->ops->prepare_ioend(wpc->ioend, error);
> +	if (wpc->ops->submit_ioend)
> +		error = wpc->ops->submit_ioend(wpc, error);
> +	else if (!error)
> +		submit_bio(&wpc->ioend->io_bio);
>  
>  	if (error) {
>  		wpc->ioend->io_bio.bi_status = errno_to_blk_status(error);
>  		bio_endio(&wpc->ioend->io_bio);
> -	} else {
> -		submit_bio(&wpc->ioend->io_bio);
>  	}
>  
>  	wpc->ioend = NULL;
> diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
> index 559a3a577097..d175853da5ae 100644
> --- a/fs/xfs/xfs_aops.c
> +++ b/fs/xfs/xfs_aops.c
> @@ -395,10 +395,11 @@ xfs_map_blocks(
>  }
>  
>  static int
> -xfs_prepare_ioend(
> -	struct iomap_ioend	*ioend,
> +xfs_submit_ioend(
> +	struct iomap_writepage_ctx *wpc,
>  	int			status)
>  {
> +	struct iomap_ioend	*ioend = wpc->ioend;
>  	unsigned int		nofs_flag;
>  
>  	/*
> @@ -420,7 +421,11 @@ xfs_prepare_ioend(
>  	if (xfs_ioend_is_append(ioend) || ioend->io_type == IOMAP_UNWRITTEN ||
>  	    (ioend->io_flags & IOMAP_F_SHARED))
>  		ioend->io_bio.bi_end_io = xfs_end_bio;
> -	return status;
> +
> +	if (status)
> +		return status;
> +	submit_bio(&ioend->io_bio);
> +	return 0;
>  }
>  
>  /*
> @@ -462,7 +467,7 @@ xfs_discard_folio(
>  
>  static const struct iomap_writeback_ops xfs_writeback_ops = {
>  	.map_blocks		= xfs_map_blocks,
> -	.prepare_ioend		= xfs_prepare_ioend,
> +	.submit_ioend		= xfs_submit_ioend,
>  	.discard_folio		= xfs_discard_folio,
>  };
>  
> diff --git a/include/linux/iomap.h b/include/linux/iomap.h
> index 5675af6b740c..c0339678d798 100644
> --- a/include/linux/iomap.h
> +++ b/include/linux/iomap.h
> @@ -362,12 +362,14 @@ struct iomap_writeback_ops {
>  			  loff_t offset, unsigned len);
>  
>  	/*
> -	 * Optional, allows the file systems to perform actions just before
> -	 * submitting the bio and/or override the bio end_io handler for complex
> -	 * operations like copy on write extent manipulation or unwritten extent
> -	 * conversions.
> +	 * Optional, allows the file systems to hook into bio submission,
> +	 * including overriding the bi_end_io handler.
> +	 *
> +	 * Returns 0 if the bio was successfully submitted, or a negative
> +	 * error code if status was non-zero or another error happened and
> +	 * the bio could not be submitted.
>  	 */
> -	int (*prepare_ioend)(struct iomap_ioend *ioend, int status);
> +	int (*submit_ioend)(struct iomap_writepage_ctx *wpc, int status);
>  
>  	/*
>  	 * Optional, allows the file system to discard state on a page where
> -- 
> 2.45.2
> 
>
diff mbox series

Patch

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 955f19e27e47..cdccf11bb3be 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1675,7 +1675,7 @@  static void iomap_writepage_end_bio(struct bio *bio)
 }
 
 /*
- * Submit the final bio for an ioend.
+ * Submit an ioend.
  *
  * If @error is non-zero, it means that we have a situation where some part of
  * the submission process has failed after we've marked pages for writeback.
@@ -1694,14 +1694,14 @@  static int iomap_submit_ioend(struct iomap_writepage_ctx *wpc, int error)
 	 * failure happened so that the file system end I/O handler gets called
 	 * to clean up.
 	 */
-	if (wpc->ops->prepare_ioend)
-		error = wpc->ops->prepare_ioend(wpc->ioend, error);
+	if (wpc->ops->submit_ioend)
+		error = wpc->ops->submit_ioend(wpc, error);
+	else if (!error)
+		submit_bio(&wpc->ioend->io_bio);
 
 	if (error) {
 		wpc->ioend->io_bio.bi_status = errno_to_blk_status(error);
 		bio_endio(&wpc->ioend->io_bio);
-	} else {
-		submit_bio(&wpc->ioend->io_bio);
 	}
 
 	wpc->ioend = NULL;
diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 559a3a577097..d175853da5ae 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -395,10 +395,11 @@  xfs_map_blocks(
 }
 
 static int
-xfs_prepare_ioend(
-	struct iomap_ioend	*ioend,
+xfs_submit_ioend(
+	struct iomap_writepage_ctx *wpc,
 	int			status)
 {
+	struct iomap_ioend	*ioend = wpc->ioend;
 	unsigned int		nofs_flag;
 
 	/*
@@ -420,7 +421,11 @@  xfs_prepare_ioend(
 	if (xfs_ioend_is_append(ioend) || ioend->io_type == IOMAP_UNWRITTEN ||
 	    (ioend->io_flags & IOMAP_F_SHARED))
 		ioend->io_bio.bi_end_io = xfs_end_bio;
-	return status;
+
+	if (status)
+		return status;
+	submit_bio(&ioend->io_bio);
+	return 0;
 }
 
 /*
@@ -462,7 +467,7 @@  xfs_discard_folio(
 
 static const struct iomap_writeback_ops xfs_writeback_ops = {
 	.map_blocks		= xfs_map_blocks,
-	.prepare_ioend		= xfs_prepare_ioend,
+	.submit_ioend		= xfs_submit_ioend,
 	.discard_folio		= xfs_discard_folio,
 };
 
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 5675af6b740c..c0339678d798 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -362,12 +362,14 @@  struct iomap_writeback_ops {
 			  loff_t offset, unsigned len);
 
 	/*
-	 * Optional, allows the file systems to perform actions just before
-	 * submitting the bio and/or override the bio end_io handler for complex
-	 * operations like copy on write extent manipulation or unwritten extent
-	 * conversions.
+	 * Optional, allows the file systems to hook into bio submission,
+	 * including overriding the bi_end_io handler.
+	 *
+	 * Returns 0 if the bio was successfully submitted, or a negative
+	 * error code if status was non-zero or another error happened and
+	 * the bio could not be submitted.
 	 */
-	int (*prepare_ioend)(struct iomap_ioend *ioend, int status);
+	int (*submit_ioend)(struct iomap_writepage_ctx *wpc, int status);
 
 	/*
 	 * Optional, allows the file system to discard state on a page where