diff mbox series

[4/6] xfs: call xfs_flush_unmap_range from xfs_free_file_space

Message ID 20240827065123.1762168-5-hch@lst.de (mailing list archive)
State New
Headers show
Series [1/6] block: remove checks for FALLOC_FL_NO_HIDE_STALE | expand

Commit Message

Christoph Hellwig Aug. 27, 2024, 6:50 a.m. UTC
Call xfs_flush_unmap_range from xfs_free_file_space so that
xfs_file_fallocate doesn't have to predict which mode will call it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_bmap_util.c |  8 ++++++++
 fs/xfs/xfs_file.c      | 21 ---------------------
 2 files changed, 8 insertions(+), 21 deletions(-)

Comments

Darrick J. Wong Aug. 27, 2024, 4:03 p.m. UTC | #1
On Tue, Aug 27, 2024 at 08:50:48AM +0200, Christoph Hellwig wrote:
> Call xfs_flush_unmap_range from xfs_free_file_space so that
> xfs_file_fallocate doesn't have to predict which mode will call it.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Hmm.  I /think/ it's ok to shift the xfs_flush_unmap_range after the
file_modified and some of the other EINVAL bailouts that can happen
before xfs_free_file_space gets called.  Effectively that means that we
can fail faster now? :)

Later on this means that the cow-around code that the rtreflink patchset
introduces will also get flushed to disk before we start
collapsing/zeroing/punching.  AFAICT that should be fine.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
>  fs/xfs/xfs_bmap_util.c |  8 ++++++++
>  fs/xfs/xfs_file.c      | 21 ---------------------
>  2 files changed, 8 insertions(+), 21 deletions(-)
> 
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index fe2e2c93097550..187a0dbda24fc4 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -848,6 +848,14 @@ xfs_free_file_space(
>  	if (len <= 0)	/* if nothing being freed */
>  		return 0;
>  
> +	/*
> +	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
> +	 * the cached range over the first operation we are about to run.
> +	 */
> +	error = xfs_flush_unmap_range(ip, offset, len);
> +	if (error)
> +		return error;
> +
>  	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
>  	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
>  
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 4cdc54dc96862e..5b9e49da06013c 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -890,27 +890,6 @@ xfs_file_fallocate(
>  	 */
>  	inode_dio_wait(inode);
>  
> -	/*
> -	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
> -	 * the cached range over the first operation we are about to run.
> -	 *
> -	 * We care about zero and collapse here because they both run a hole
> -	 * punch over the range first. Because that can zero data, and the range
> -	 * of invalidation for the shift operations is much larger, we still do
> -	 * the required flush for collapse in xfs_prepare_shift().
> -	 *
> -	 * Insert has the same range requirements as collapse, and we extend the
> -	 * file first which can zero data. Hence insert has the same
> -	 * flush/invalidate requirements as collapse and so they are both
> -	 * handled at the right time by xfs_prepare_shift().
> -	 */
> -	if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE |
> -		    FALLOC_FL_COLLAPSE_RANGE)) {
> -		error = xfs_flush_unmap_range(ip, offset, len);
> -		if (error)
> -			goto out_unlock;
> -	}
> -
>  	error = file_modified(file);
>  	if (error)
>  		goto out_unlock;
> -- 
> 2.43.0
> 
>
Christoph Hellwig Aug. 28, 2024, 4:06 a.m. UTC | #2
On Tue, Aug 27, 2024 at 09:03:23AM -0700, Darrick J. Wong wrote:
> On Tue, Aug 27, 2024 at 08:50:48AM +0200, Christoph Hellwig wrote:
> > Call xfs_flush_unmap_range from xfs_free_file_space so that
> > xfs_file_fallocate doesn't have to predict which mode will call it.
> > 
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> 
> Hmm.  I /think/ it's ok to shift the xfs_flush_unmap_range after the
> file_modified and some of the other EINVAL bailouts that can happen
> before xfs_free_file_space gets called.  Effectively that means that we
> can fail faster now? :)

Yes, failing faster has always been my personal benchmark :)
Dave Chinner Aug. 29, 2024, 3:03 a.m. UTC | #3
On Tue, Aug 27, 2024 at 08:50:48AM +0200, Christoph Hellwig wrote:
> Call xfs_flush_unmap_range from xfs_free_file_space so that
> xfs_file_fallocate doesn't have to predict which mode will call it.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/xfs/xfs_bmap_util.c |  8 ++++++++
>  fs/xfs/xfs_file.c      | 21 ---------------------
>  2 files changed, 8 insertions(+), 21 deletions(-)
> 
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index fe2e2c93097550..187a0dbda24fc4 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -848,6 +848,14 @@ xfs_free_file_space(
>  	if (len <= 0)	/* if nothing being freed */
>  		return 0;
>  
> +	/*
> +	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
> +	 * the cached range over the first operation we are about to run.
> +	 */
> +	error = xfs_flush_unmap_range(ip, offset, len);
> +	if (error)
> +		return error;
> +
>  	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
>  	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);

Ok, so if we ever change the zeroing implementation to not punch a
hole first, we're going to have to make sure we add this to whatever
new zeroing implementation we have.

Can you leave a comment in the FALLOC_FL_ZERO_RANGE implementation
code that notes it currently relies on the xfs_flush_unmap_range()
in xfs_free_file_space() for correct operation?

-Dave.
Christoph Hellwig Aug. 29, 2024, 3:54 a.m. UTC | #4
On Thu, Aug 29, 2024 at 01:03:31PM +1000, Dave Chinner wrote:
> > @@ -848,6 +848,14 @@ xfs_free_file_space(
> >  	if (len <= 0)	/* if nothing being freed */
> >  		return 0;
> >  
> > +	/*
> > +	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
> > +	 * the cached range over the first operation we are about to run.
> > +	 */
> > +	error = xfs_flush_unmap_range(ip, offset, len);
> > +	if (error)
> > +		return error;
> > +
> >  	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
> >  	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
> 
> Ok, so if we ever change the zeroing implementation to not punch a
> hole first, we're going to have to make sure we add this to whatever
> new zeroing implementation we have.
> 
> Can you leave a comment in the FALLOC_FL_ZERO_RANGE implementation
> code that notes it currently relies on the xfs_flush_unmap_range()
> in xfs_free_file_space() for correct operation?

Sure.
diff mbox series

Patch

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index fe2e2c93097550..187a0dbda24fc4 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -848,6 +848,14 @@  xfs_free_file_space(
 	if (len <= 0)	/* if nothing being freed */
 		return 0;
 
+	/*
+	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
+	 * the cached range over the first operation we are about to run.
+	 */
+	error = xfs_flush_unmap_range(ip, offset, len);
+	if (error)
+		return error;
+
 	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
 	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
 
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 4cdc54dc96862e..5b9e49da06013c 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -890,27 +890,6 @@  xfs_file_fallocate(
 	 */
 	inode_dio_wait(inode);
 
-	/*
-	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
-	 * the cached range over the first operation we are about to run.
-	 *
-	 * We care about zero and collapse here because they both run a hole
-	 * punch over the range first. Because that can zero data, and the range
-	 * of invalidation for the shift operations is much larger, we still do
-	 * the required flush for collapse in xfs_prepare_shift().
-	 *
-	 * Insert has the same range requirements as collapse, and we extend the
-	 * file first which can zero data. Hence insert has the same
-	 * flush/invalidate requirements as collapse and so they are both
-	 * handled at the right time by xfs_prepare_shift().
-	 */
-	if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE |
-		    FALLOC_FL_COLLAPSE_RANGE)) {
-		error = xfs_flush_unmap_range(ip, offset, len);
-		if (error)
-			goto out_unlock;
-	}
-
 	error = file_modified(file);
 	if (error)
 		goto out_unlock;