sync_blockdev_range() is to support syncing multiple sectors
with as few block device requests as possible, it is helpful
to make the block device to give full play to its performance.
Signed-off-by: Yuezhang Mo <[email protected]>
Suggested-by: Christoph Hellwig <[email protected]>
Reviewed-by: Andy Wu <[email protected]>
Reviewed-by: Aoyama Wataru <[email protected]>
cc: Jens Axboe <[email protected]>
---
block/bdev.c | 10 ++++++++++
include/linux/blkdev.h | 6 ++++++
2 files changed, 16 insertions(+)
diff --git a/block/bdev.c b/block/bdev.c
index 102837a37051..57043e4f3322 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -200,6 +200,16 @@ int sync_blockdev(struct block_device *bdev)
}
EXPORT_SYMBOL(sync_blockdev);
+int sync_blockdev_range(struct block_device *bdev, loff_t lstart, loff_t lend)
+{
+ if (!bdev)
+ return 0;
+
+ return filemap_write_and_wait_range(bdev->bd_inode->i_mapping,
+ lstart, lend);
+}
+EXPORT_SYMBOL(sync_blockdev_range);
+
/*
* Write out and wait upon all dirty data associated with this
* device. Filesystem data as well as the underlying block
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 16b47035e4b0..1e85d0688d9c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1310,6 +1310,7 @@ int truncate_bdev_range(struct block_device *bdev, fmode_t mode, loff_t lstart,
#ifdef CONFIG_BLOCK
void invalidate_bdev(struct block_device *bdev);
int sync_blockdev(struct block_device *bdev);
+int sync_blockdev_range(struct block_device *bdev, loff_t lstart, loff_t lend);
int sync_blockdev_nowait(struct block_device *bdev);
void sync_bdevs(bool wait);
#else
@@ -1320,6 +1321,11 @@ static inline int sync_blockdev(struct block_device *bdev)
{
return 0;
}
+static inline int sync_blockdev_range(struct block_device *bdev, loff_t lstart,
+ loff_t lend)
+{
+ return 0;
+}
static inline int sync_blockdev_nowait(struct block_device *bdev)
{
return 0;
--
2.25.1
On Sat, Apr 02, 2022 at 03:28:00AM +0000, [email protected] wrote:
> sync_blockdev_range() is to support syncing multiple sectors
> with as few block device requests as possible, it is helpful
> to make the block device to give full play to its performance.
>
> Signed-off-by: Yuezhang Mo <[email protected]>
> Suggested-by: Christoph Hellwig <[email protected]>
> Reviewed-by: Andy Wu <[email protected]>
> Reviewed-by: Aoyama Wataru <[email protected]>
> cc: Jens Axboe <[email protected]>
> ---
> block/bdev.c | 10 ++++++++++
> include/linux/blkdev.h | 6 ++++++
> 2 files changed, 16 insertions(+)
>
> diff --git a/block/bdev.c b/block/bdev.c
> index 102837a37051..57043e4f3322 100644
> --- a/block/bdev.c
> +++ b/block/bdev.c
> @@ -200,6 +200,16 @@ int sync_blockdev(struct block_device *bdev)
> }
> EXPORT_SYMBOL(sync_blockdev);
>
> +int sync_blockdev_range(struct block_device *bdev, loff_t lstart, loff_t lend)
> +{
> + if (!bdev)
> + return 0;
This check isn't really needed, and I don't think we need a
!CONFIG_BLOCK stub for this either.
> From: Christoph Hellwig <[email protected]>
> > --- a/block/bdev.c
> > +++ b/block/bdev.c
> > @@ -200,6 +200,16 @@ int sync_blockdev(struct block_device *bdev) }
> > EXPORT_SYMBOL(sync_blockdev);
> >
> > +int sync_blockdev_range(struct block_device *bdev, loff_t lstart,
> > +loff_t lend) {
> > + if (!bdev)
> > + return 0;
>
> This check isn't really needed, and I don't think we need a !CONFIG_BLOCK
> stub for this either.
sync_blockdev() and related helpers have this check and a !CONFIG_BLOCK stub.
I would like to understand the background of your comment, could you explain a little more?
Thanks.
On Wed, Apr 06, 2022 at 10:21:15AM +0000, [email protected] wrote:
> > From: Christoph Hellwig <[email protected]>
> > > --- a/block/bdev.c
> > > +++ b/block/bdev.c
> > > @@ -200,6 +200,16 @@ int sync_blockdev(struct block_device *bdev) }
> > > EXPORT_SYMBOL(sync_blockdev);
> > >
> > > +int sync_blockdev_range(struct block_device *bdev, loff_t lstart,
> > > +loff_t lend) {
> > > + if (!bdev)
> > > + return 0;
> >
> > This check isn't really needed, and I don't think we need a !CONFIG_BLOCK
> > stub for this either.
>
> sync_blockdev() and related helpers have this check and a !CONFIG_BLOCK stub.
> I would like to understand the background of your comment, could you explain a little more?
sync_blockdev and sync_blockdev do that because they are unconditionally
called from sync_filesystem, and not just from block-dependent code.
Eventually that should be cleaned up as well, but please don't add it to
new code.
> From: Christoph Hellwig <[email protected]>
> > > This check isn't really needed, and I don't think we need a
> > > !CONFIG_BLOCK stub for this either.
> >
> > sync_blockdev() and related helpers have this check and a !CONFIG_BLOCK
> stub.
> > I would like to understand the background of your comment, could you
> explain a little more?
>
> sync_blockdev and sync_blockdev do that because they are unconditionally
> called from sync_filesystem, and not just from block-dependent code.
> Eventually that should be cleaned up as well, but please don't add it to new
> code.
Thank you for your explanation.
I will update the patch to remove the check and the !CONFIG_BLOCK stub.